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-rw-r--r--fs/ext4/Makefile12
-rw-r--r--fs/ext4/acl.c551
-rw-r--r--fs/ext4/acl.h81
-rw-r--r--fs/ext4/balloc.c1833
-rw-r--r--fs/ext4/bitmap.c32
-rw-r--r--fs/ext4/dir.c518
-rw-r--r--fs/ext4/extents.c2152
-rw-r--r--fs/ext4/file.c139
-rw-r--r--fs/ext4/fsync.c88
-rw-r--r--fs/ext4/hash.c152
-rw-r--r--fs/ext4/ialloc.c772
-rw-r--r--fs/ext4/inode.c3233
-rw-r--r--fs/ext4/ioctl.c306
-rw-r--r--fs/ext4/namei.c2395
-rw-r--r--fs/ext4/namei.h8
-rw-r--r--fs/ext4/resize.c1045
-rw-r--r--fs/ext4/super.c2829
-rw-r--r--fs/ext4/symlink.c54
-rw-r--r--fs/ext4/xattr.c1317
-rw-r--r--fs/ext4/xattr.h145
-rw-r--r--fs/ext4/xattr_security.c77
-rw-r--r--fs/ext4/xattr_trusted.c62
-rw-r--r--fs/ext4/xattr_user.c64
23 files changed, 17865 insertions, 0 deletions
diff --git a/fs/ext4/Makefile b/fs/ext4/Makefile
new file mode 100644
index 000000000000..a6acb96ebeb9
--- /dev/null
+++ b/fs/ext4/Makefile
@@ -0,0 +1,12 @@
+#
+# Makefile for the linux ext4-filesystem routines.
+#
+
+obj-$(CONFIG_EXT4DEV_FS) += ext4dev.o
+
+ext4dev-y := balloc.o bitmap.o dir.o file.o fsync.o ialloc.o inode.o \
+ ioctl.o namei.o super.o symlink.o hash.o resize.o extents.o
+
+ext4dev-$(CONFIG_EXT4DEV_FS_XATTR) += xattr.o xattr_user.o xattr_trusted.o
+ext4dev-$(CONFIG_EXT4DEV_FS_POSIX_ACL) += acl.o
+ext4dev-$(CONFIG_EXT4DEV_FS_SECURITY) += xattr_security.o
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
new file mode 100644
index 000000000000..9e882546d91a
--- /dev/null
+++ b/fs/ext4/acl.c
@@ -0,0 +1,551 @@
+/*
+ * linux/fs/ext4/acl.c
+ *
+ * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/capability.h>
+#include <linux/fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/ext4_fs.h>
+#include "xattr.h"
+#include "acl.h"
+
+/*
+ * Convert from filesystem to in-memory representation.
+ */
+static struct posix_acl *
+ext4_acl_from_disk(const void *value, size_t size)
+{
+ const char *end = (char *)value + size;
+ int n, count;
+ struct posix_acl *acl;
+
+ if (!value)
+ return NULL;
+ if (size < sizeof(ext4_acl_header))
+ return ERR_PTR(-EINVAL);
+ if (((ext4_acl_header *)value)->a_version !=
+ cpu_to_le32(EXT4_ACL_VERSION))
+ return ERR_PTR(-EINVAL);
+ value = (char *)value + sizeof(ext4_acl_header);
+ count = ext4_acl_count(size);
+ if (count < 0)
+ return ERR_PTR(-EINVAL);
+ if (count == 0)
+ return NULL;
+ acl = posix_acl_alloc(count, GFP_KERNEL);
+ if (!acl)
+ return ERR_PTR(-ENOMEM);
+ for (n=0; n < count; n++) {
+ ext4_acl_entry *entry =
+ (ext4_acl_entry *)value;
+ if ((char *)value + sizeof(ext4_acl_entry_short) > end)
+ goto fail;
+ acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
+ acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
+ switch(acl->a_entries[n].e_tag) {
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ value = (char *)value +
+ sizeof(ext4_acl_entry_short);
+ acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
+ break;
+
+ case ACL_USER:
+ case ACL_GROUP:
+ value = (char *)value + sizeof(ext4_acl_entry);
+ if ((char *)value > end)
+ goto fail;
+ acl->a_entries[n].e_id =
+ le32_to_cpu(entry->e_id);
+ break;
+
+ default:
+ goto fail;
+ }
+ }
+ if (value != end)
+ goto fail;
+ return acl;
+
+fail:
+ posix_acl_release(acl);
+ return ERR_PTR(-EINVAL);
+}
+
+/*
+ * Convert from in-memory to filesystem representation.
+ */
+static void *
+ext4_acl_to_disk(const struct posix_acl *acl, size_t *size)
+{
+ ext4_acl_header *ext_acl;
+ char *e;
+ size_t n;
+
+ *size = ext4_acl_size(acl->a_count);
+ ext_acl = kmalloc(sizeof(ext4_acl_header) + acl->a_count *
+ sizeof(ext4_acl_entry), GFP_KERNEL);
+ if (!ext_acl)
+ return ERR_PTR(-ENOMEM);
+ ext_acl->a_version = cpu_to_le32(EXT4_ACL_VERSION);
+ e = (char *)ext_acl + sizeof(ext4_acl_header);
+ for (n=0; n < acl->a_count; n++) {
+ ext4_acl_entry *entry = (ext4_acl_entry *)e;
+ entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
+ entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
+ switch(acl->a_entries[n].e_tag) {
+ case ACL_USER:
+ case ACL_GROUP:
+ entry->e_id =
+ cpu_to_le32(acl->a_entries[n].e_id);
+ e += sizeof(ext4_acl_entry);
+ break;
+
+ case ACL_USER_OBJ:
+ case ACL_GROUP_OBJ:
+ case ACL_MASK:
+ case ACL_OTHER:
+ e += sizeof(ext4_acl_entry_short);
+ break;
+
+ default:
+ goto fail;
+ }
+ }
+ return (char *)ext_acl;
+
+fail:
+ kfree(ext_acl);
+ return ERR_PTR(-EINVAL);
+}
+
+static inline struct posix_acl *
+ext4_iget_acl(struct inode *inode, struct posix_acl **i_acl)
+{
+ struct posix_acl *acl = EXT4_ACL_NOT_CACHED;
+
+ spin_lock(&inode->i_lock);
+ if (*i_acl != EXT4_ACL_NOT_CACHED)
+ acl = posix_acl_dup(*i_acl);
+ spin_unlock(&inode->i_lock);
+
+ return acl;
+}
+
+static inline void
+ext4_iset_acl(struct inode *inode, struct posix_acl **i_acl,
+ struct posix_acl *acl)
+{
+ spin_lock(&inode->i_lock);
+ if (*i_acl != EXT4_ACL_NOT_CACHED)
+ posix_acl_release(*i_acl);
+ *i_acl = posix_acl_dup(acl);
+ spin_unlock(&inode->i_lock);
+}
+
+/*
+ * Inode operation get_posix_acl().
+ *
+ * inode->i_mutex: don't care
+ */
+static struct posix_acl *
+ext4_get_acl(struct inode *inode, int type)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ int name_index;
+ char *value = NULL;
+ struct posix_acl *acl;
+ int retval;
+
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return NULL;
+
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ acl = ext4_iget_acl(inode, &ei->i_acl);
+ if (acl != EXT4_ACL_NOT_CACHED)
+ return acl;
+ name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS;
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ acl = ext4_iget_acl(inode, &ei->i_default_acl);
+ if (acl != EXT4_ACL_NOT_CACHED)
+ return acl;
+ name_index = EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT;
+ break;
+
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+ retval = ext4_xattr_get(inode, name_index, "", NULL, 0);
+ if (retval > 0) {
+ value = kmalloc(retval, GFP_KERNEL);
+ if (!value)
+ return ERR_PTR(-ENOMEM);
+ retval = ext4_xattr_get(inode, name_index, "", value, retval);
+ }
+ if (retval > 0)
+ acl = ext4_acl_from_disk(value, retval);
+ else if (retval == -ENODATA || retval == -ENOSYS)
+ acl = NULL;
+ else
+ acl = ERR_PTR(retval);
+ kfree(value);
+
+ if (!IS_ERR(acl)) {
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ ext4_iset_acl(inode, &ei->i_acl, acl);
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ ext4_iset_acl(inode, &ei->i_default_acl, acl);
+ break;
+ }
+ }
+ return acl;
+}
+
+/*
+ * Set the access or default ACL of an inode.
+ *
+ * inode->i_mutex: down unless called from ext4_new_inode
+ */
+static int
+ext4_set_acl(handle_t *handle, struct inode *inode, int type,
+ struct posix_acl *acl)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ int name_index;
+ void *value = NULL;
+ size_t size = 0;
+ int error;
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ name_index = EXT4_XATTR_INDEX_POSIX_ACL_ACCESS;
+ if (acl) {
+ mode_t mode = inode->i_mode;
+ error = posix_acl_equiv_mode(acl, &mode);
+ if (error < 0)
+ return error;
+ else {
+ inode->i_mode = mode;
+ ext4_mark_inode_dirty(handle, inode);
+ if (error == 0)
+ acl = NULL;
+ }
+ }
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ name_index = EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT;
+ if (!S_ISDIR(inode->i_mode))
+ return acl ? -EACCES : 0;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ if (acl) {
+ value = ext4_acl_to_disk(acl, &size);
+ if (IS_ERR(value))
+ return (int)PTR_ERR(value);
+ }
+
+ error = ext4_xattr_set_handle(handle, inode, name_index, "",
+ value, size, 0);
+
+ kfree(value);
+ if (!error) {
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ ext4_iset_acl(inode, &ei->i_acl, acl);
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ ext4_iset_acl(inode, &ei->i_default_acl, acl);
+ break;
+ }
+ }
+ return error;
+}
+
+static int
+ext4_check_acl(struct inode *inode, int mask)
+{
+ struct posix_acl *acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
+
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl) {
+ int error = posix_acl_permission(inode, acl, mask);
+ posix_acl_release(acl);
+ return error;
+ }
+
+ return -EAGAIN;
+}
+
+int
+ext4_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ return generic_permission(inode, mask, ext4_check_acl);
+}
+
+/*
+ * Initialize the ACLs of a new inode. Called from ext4_new_inode.
+ *
+ * dir->i_mutex: down
+ * inode->i_mutex: up (access to inode is still exclusive)
+ */
+int
+ext4_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
+{
+ struct posix_acl *acl = NULL;
+ int error = 0;
+
+ if (!S_ISLNK(inode->i_mode)) {
+ if (test_opt(dir->i_sb, POSIX_ACL)) {
+ acl = ext4_get_acl(dir, ACL_TYPE_DEFAULT);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ }
+ if (!acl)
+ inode->i_mode &= ~current->fs->umask;
+ }
+ if (test_opt(inode->i_sb, POSIX_ACL) && acl) {
+ struct posix_acl *clone;
+ mode_t mode;
+
+ if (S_ISDIR(inode->i_mode)) {
+ error = ext4_set_acl(handle, inode,
+ ACL_TYPE_DEFAULT, acl);
+ if (error)
+ goto cleanup;
+ }
+ clone = posix_acl_clone(acl, GFP_KERNEL);
+ error = -ENOMEM;
+ if (!clone)
+ goto cleanup;
+
+ mode = inode->i_mode;
+ error = posix_acl_create_masq(clone, &mode);
+ if (error >= 0) {
+ inode->i_mode = mode;
+ if (error > 0) {
+ /* This is an extended ACL */
+ error = ext4_set_acl(handle, inode,
+ ACL_TYPE_ACCESS, clone);
+ }
+ }
+ posix_acl_release(clone);
+ }
+cleanup:
+ posix_acl_release(acl);
+ return error;
+}
+
+/*
+ * Does chmod for an inode that may have an Access Control List. The
+ * inode->i_mode field must be updated to the desired value by the caller
+ * before calling this function.
+ * Returns 0 on success, or a negative error number.
+ *
+ * We change the ACL rather than storing some ACL entries in the file
+ * mode permission bits (which would be more efficient), because that
+ * would break once additional permissions (like ACL_APPEND, ACL_DELETE
+ * for directories) are added. There are no more bits available in the
+ * file mode.
+ *
+ * inode->i_mutex: down
+ */
+int
+ext4_acl_chmod(struct inode *inode)
+{
+ struct posix_acl *acl, *clone;
+ int error;
+
+ if (S_ISLNK(inode->i_mode))
+ return -EOPNOTSUPP;
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return 0;
+ acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
+ if (IS_ERR(acl) || !acl)
+ return PTR_ERR(acl);
+ clone = posix_acl_clone(acl, GFP_KERNEL);
+ posix_acl_release(acl);
+ if (!clone)
+ return -ENOMEM;
+ error = posix_acl_chmod_masq(clone, inode->i_mode);
+ if (!error) {
+ handle_t *handle;
+ int retries = 0;
+
+ retry:
+ handle = ext4_journal_start(inode,
+ EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle)) {
+ error = PTR_ERR(handle);
+ ext4_std_error(inode->i_sb, error);
+ goto out;
+ }
+ error = ext4_set_acl(handle, inode, ACL_TYPE_ACCESS, clone);
+ ext4_journal_stop(handle);
+ if (error == -ENOSPC &&
+ ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+ }
+out:
+ posix_acl_release(clone);
+ return error;
+}
+
+/*
+ * Extended attribute handlers
+ */
+static size_t
+ext4_xattr_list_acl_access(struct inode *inode, char *list, size_t list_len,
+ const char *name, size_t name_len)
+{
+ const size_t size = sizeof(POSIX_ACL_XATTR_ACCESS);
+
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return 0;
+ if (list && size <= list_len)
+ memcpy(list, POSIX_ACL_XATTR_ACCESS, size);
+ return size;
+}
+
+static size_t
+ext4_xattr_list_acl_default(struct inode *inode, char *list, size_t list_len,
+ const char *name, size_t name_len)
+{
+ const size_t size = sizeof(POSIX_ACL_XATTR_DEFAULT);
+
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return 0;
+ if (list && size <= list_len)
+ memcpy(list, POSIX_ACL_XATTR_DEFAULT, size);
+ return size;
+}
+
+static int
+ext4_xattr_get_acl(struct inode *inode, int type, void *buffer, size_t size)
+{
+ struct posix_acl *acl;
+ int error;
+
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return -EOPNOTSUPP;
+
+ acl = ext4_get_acl(inode, type);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl == NULL)
+ return -ENODATA;
+ error = posix_acl_to_xattr(acl, buffer, size);
+ posix_acl_release(acl);
+
+ return error;
+}
+
+static int
+ext4_xattr_get_acl_access(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ return ext4_xattr_get_acl(inode, ACL_TYPE_ACCESS, buffer, size);
+}
+
+static int
+ext4_xattr_get_acl_default(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ return ext4_xattr_get_acl(inode, ACL_TYPE_DEFAULT, buffer, size);
+}
+
+static int
+ext4_xattr_set_acl(struct inode *inode, int type, const void *value,
+ size_t size)
+{
+ handle_t *handle;
+ struct posix_acl *acl;
+ int error, retries = 0;
+
+ if (!test_opt(inode->i_sb, POSIX_ACL))
+ return -EOPNOTSUPP;
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+ return -EPERM;
+
+ if (value) {
+ acl = posix_acl_from_xattr(value, size);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ else if (acl) {
+ error = posix_acl_valid(acl);
+ if (error)
+ goto release_and_out;
+ }
+ } else
+ acl = NULL;
+
+retry:
+ handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ error = ext4_set_acl(handle, inode, type, acl);
+ ext4_journal_stop(handle);
+ if (error == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+
+release_and_out:
+ posix_acl_release(acl);
+ return error;
+}
+
+static int
+ext4_xattr_set_acl_access(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ return ext4_xattr_set_acl(inode, ACL_TYPE_ACCESS, value, size);
+}
+
+static int
+ext4_xattr_set_acl_default(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") != 0)
+ return -EINVAL;
+ return ext4_xattr_set_acl(inode, ACL_TYPE_DEFAULT, value, size);
+}
+
+struct xattr_handler ext4_xattr_acl_access_handler = {
+ .prefix = POSIX_ACL_XATTR_ACCESS,
+ .list = ext4_xattr_list_acl_access,
+ .get = ext4_xattr_get_acl_access,
+ .set = ext4_xattr_set_acl_access,
+};
+
+struct xattr_handler ext4_xattr_acl_default_handler = {
+ .prefix = POSIX_ACL_XATTR_DEFAULT,
+ .list = ext4_xattr_list_acl_default,
+ .get = ext4_xattr_get_acl_default,
+ .set = ext4_xattr_set_acl_default,
+};
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
new file mode 100644
index 000000000000..26a5c1abf147
--- /dev/null
+++ b/fs/ext4/acl.h
@@ -0,0 +1,81 @@
+/*
+ File: fs/ext4/acl.h
+
+ (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
+*/
+
+#include <linux/posix_acl_xattr.h>
+
+#define EXT4_ACL_VERSION 0x0001
+
+typedef struct {
+ __le16 e_tag;
+ __le16 e_perm;
+ __le32 e_id;
+} ext4_acl_entry;
+
+typedef struct {
+ __le16 e_tag;
+ __le16 e_perm;
+} ext4_acl_entry_short;
+
+typedef struct {
+ __le32 a_version;
+} ext4_acl_header;
+
+static inline size_t ext4_acl_size(int count)
+{
+ if (count <= 4) {
+ return sizeof(ext4_acl_header) +
+ count * sizeof(ext4_acl_entry_short);
+ } else {
+ return sizeof(ext4_acl_header) +
+ 4 * sizeof(ext4_acl_entry_short) +
+ (count - 4) * sizeof(ext4_acl_entry);
+ }
+}
+
+static inline int ext4_acl_count(size_t size)
+{
+ ssize_t s;
+ size -= sizeof(ext4_acl_header);
+ s = size - 4 * sizeof(ext4_acl_entry_short);
+ if (s < 0) {
+ if (size % sizeof(ext4_acl_entry_short))
+ return -1;
+ return size / sizeof(ext4_acl_entry_short);
+ } else {
+ if (s % sizeof(ext4_acl_entry))
+ return -1;
+ return s / sizeof(ext4_acl_entry) + 4;
+ }
+}
+
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+
+/* Value for inode->u.ext4_i.i_acl and inode->u.ext4_i.i_default_acl
+ if the ACL has not been cached */
+#define EXT4_ACL_NOT_CACHED ((void *)-1)
+
+/* acl.c */
+extern int ext4_permission (struct inode *, int, struct nameidata *);
+extern int ext4_acl_chmod (struct inode *);
+extern int ext4_init_acl (handle_t *, struct inode *, struct inode *);
+
+#else /* CONFIG_EXT4DEV_FS_POSIX_ACL */
+#include <linux/sched.h>
+#define ext4_permission NULL
+
+static inline int
+ext4_acl_chmod(struct inode *inode)
+{
+ return 0;
+}
+
+static inline int
+ext4_init_acl(handle_t *handle, struct inode *inode, struct inode *dir)
+{
+ return 0;
+}
+#endif /* CONFIG_EXT4DEV_FS_POSIX_ACL */
+
diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
new file mode 100644
index 000000000000..5d45582f9517
--- /dev/null
+++ b/fs/ext4/balloc.c
@@ -0,0 +1,1833 @@
+/*
+ * linux/fs/ext4/balloc.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * Enhanced block allocation by Stephen Tweedie (sct@redhat.com), 1993
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/time.h>
+#include <linux/capability.h>
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/quotaops.h>
+#include <linux/buffer_head.h>
+
+/*
+ * balloc.c contains the blocks allocation and deallocation routines
+ */
+
+/*
+ * Calculate the block group number and offset, given a block number
+ */
+void ext4_get_group_no_and_offset(struct super_block *sb, ext4_fsblk_t blocknr,
+ unsigned long *blockgrpp, ext4_grpblk_t *offsetp)
+{
+ struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+ ext4_grpblk_t offset;
+
+ blocknr = blocknr - le32_to_cpu(es->s_first_data_block);
+ offset = do_div(blocknr, EXT4_BLOCKS_PER_GROUP(sb));
+ if (offsetp)
+ *offsetp = offset;
+ if (blockgrpp)
+ *blockgrpp = blocknr;
+
+}
+
+/*
+ * The free blocks are managed by bitmaps. A file system contains several
+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
+ * block for inodes, N blocks for the inode table and data blocks.
+ *
+ * The file system contains group descriptors which are located after the
+ * super block. Each descriptor contains the number of the bitmap block and
+ * the free blocks count in the block. The descriptors are loaded in memory
+ * when a file system is mounted (see ext4_read_super).
+ */
+
+
+#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
+
+/**
+ * ext4_get_group_desc() -- load group descriptor from disk
+ * @sb: super block
+ * @block_group: given block group
+ * @bh: pointer to the buffer head to store the block
+ * group descriptor
+ */
+struct ext4_group_desc * ext4_get_group_desc(struct super_block * sb,
+ unsigned int block_group,
+ struct buffer_head ** bh)
+{
+ unsigned long group_desc;
+ unsigned long offset;
+ struct ext4_group_desc * desc;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ if (block_group >= sbi->s_groups_count) {
+ ext4_error (sb, "ext4_get_group_desc",
+ "block_group >= groups_count - "
+ "block_group = %d, groups_count = %lu",
+ block_group, sbi->s_groups_count);
+
+ return NULL;
+ }
+ smp_rmb();
+
+ group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
+ offset = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
+ if (!sbi->s_group_desc[group_desc]) {
+ ext4_error (sb, "ext4_get_group_desc",
+ "Group descriptor not loaded - "
+ "block_group = %d, group_desc = %lu, desc = %lu",
+ block_group, group_desc, offset);
+ return NULL;
+ }
+
+ desc = (struct ext4_group_desc *)(
+ (__u8 *)sbi->s_group_desc[group_desc]->b_data +
+ offset * EXT4_DESC_SIZE(sb));
+ if (bh)
+ *bh = sbi->s_group_desc[group_desc];
+ return desc;
+}
+
+/**
+ * read_block_bitmap()
+ * @sb: super block
+ * @block_group: given block group
+ *
+ * Read the bitmap for a given block_group, reading into the specified
+ * slot in the superblock's bitmap cache.
+ *
+ * Return buffer_head on success or NULL in case of failure.
+ */
+static struct buffer_head *
+read_block_bitmap(struct super_block *sb, unsigned int block_group)
+{
+ struct ext4_group_desc * desc;
+ struct buffer_head * bh = NULL;
+
+ desc = ext4_get_group_desc (sb, block_group, NULL);
+ if (!desc)
+ goto error_out;
+ bh = sb_bread(sb, ext4_block_bitmap(sb, desc));
+ if (!bh)
+ ext4_error (sb, "read_block_bitmap",
+ "Cannot read block bitmap - "
+ "block_group = %d, block_bitmap = %llu",
+ block_group,
+ ext4_block_bitmap(sb, desc));
+error_out:
+ return bh;
+}
+/*
+ * The reservation window structure operations
+ * --------------------------------------------
+ * Operations include:
+ * dump, find, add, remove, is_empty, find_next_reservable_window, etc.
+ *
+ * We use a red-black tree to represent per-filesystem reservation
+ * windows.
+ *
+ */
+
+/**
+ * __rsv_window_dump() -- Dump the filesystem block allocation reservation map
+ * @rb_root: root of per-filesystem reservation rb tree
+ * @verbose: verbose mode
+ * @fn: function which wishes to dump the reservation map
+ *
+ * If verbose is turned on, it will print the whole block reservation
+ * windows(start, end). Otherwise, it will only print out the "bad" windows,
+ * those windows that overlap with their immediate neighbors.
+ */
+#if 1
+static void __rsv_window_dump(struct rb_root *root, int verbose,
+ const char *fn)
+{
+ struct rb_node *n;
+ struct ext4_reserve_window_node *rsv, *prev;
+ int bad;
+
+restart:
+ n = rb_first(root);
+ bad = 0;
+ prev = NULL;
+
+ printk("Block Allocation Reservation Windows Map (%s):\n", fn);
+ while (n) {
+ rsv = list_entry(n, struct ext4_reserve_window_node, rsv_node);
+ if (verbose)
+ printk("reservation window 0x%p "
+ "start: %llu, end: %llu\n",
+ rsv, rsv->rsv_start, rsv->rsv_end);
+ if (rsv->rsv_start && rsv->rsv_start >= rsv->rsv_end) {
+ printk("Bad reservation %p (start >= end)\n",
+ rsv);
+ bad = 1;
+ }
+ if (prev && prev->rsv_end >= rsv->rsv_start) {
+ printk("Bad reservation %p (prev->end >= start)\n",
+ rsv);
+ bad = 1;
+ }
+ if (bad) {
+ if (!verbose) {
+ printk("Restarting reservation walk in verbose mode\n");
+ verbose = 1;
+ goto restart;
+ }
+ }
+ n = rb_next(n);
+ prev = rsv;
+ }
+ printk("Window map complete.\n");
+ if (bad)
+ BUG();
+}
+#define rsv_window_dump(root, verbose) \
+ __rsv_window_dump((root), (verbose), __FUNCTION__)
+#else
+#define rsv_window_dump(root, verbose) do {} while (0)
+#endif
+
+/**
+ * goal_in_my_reservation()
+ * @rsv: inode's reservation window
+ * @grp_goal: given goal block relative to the allocation block group
+ * @group: the current allocation block group
+ * @sb: filesystem super block
+ *
+ * Test if the given goal block (group relative) is within the file's
+ * own block reservation window range.
+ *
+ * If the reservation window is outside the goal allocation group, return 0;
+ * grp_goal (given goal block) could be -1, which means no specific
+ * goal block. In this case, always return 1.
+ * If the goal block is within the reservation window, return 1;
+ * otherwise, return 0;
+ */
+static int
+goal_in_my_reservation(struct ext4_reserve_window *rsv, ext4_grpblk_t grp_goal,
+ unsigned int group, struct super_block * sb)
+{
+ ext4_fsblk_t group_first_block, group_last_block;
+
+ group_first_block = ext4_group_first_block_no(sb, group);
+ group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
+
+ if ((rsv->_rsv_start > group_last_block) ||
+ (rsv->_rsv_end < group_first_block))
+ return 0;
+ if ((grp_goal >= 0) && ((grp_goal + group_first_block < rsv->_rsv_start)
+ || (grp_goal + group_first_block > rsv->_rsv_end)))
+ return 0;
+ return 1;
+}
+
+/**
+ * search_reserve_window()
+ * @rb_root: root of reservation tree
+ * @goal: target allocation block
+ *
+ * Find the reserved window which includes the goal, or the previous one
+ * if the goal is not in any window.
+ * Returns NULL if there are no windows or if all windows start after the goal.
+ */
+static struct ext4_reserve_window_node *
+search_reserve_window(struct rb_root *root, ext4_fsblk_t goal)
+{
+ struct rb_node *n = root->rb_node;
+ struct ext4_reserve_window_node *rsv;
+
+ if (!n)
+ return NULL;
+
+ do {
+ rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
+
+ if (goal < rsv->rsv_start)
+ n = n->rb_left;
+ else if (goal > rsv->rsv_end)
+ n = n->rb_right;
+ else
+ return rsv;
+ } while (n);
+ /*
+ * We've fallen off the end of the tree: the goal wasn't inside
+ * any particular node. OK, the previous node must be to one
+ * side of the interval containing the goal. If it's the RHS,
+ * we need to back up one.
+ */
+ if (rsv->rsv_start > goal) {
+ n = rb_prev(&rsv->rsv_node);
+ rsv = rb_entry(n, struct ext4_reserve_window_node, rsv_node);
+ }
+ return rsv;
+}
+
+/**
+ * ext4_rsv_window_add() -- Insert a window to the block reservation rb tree.
+ * @sb: super block
+ * @rsv: reservation window to add
+ *
+ * Must be called with rsv_lock hold.
+ */
+void ext4_rsv_window_add(struct super_block *sb,
+ struct ext4_reserve_window_node *rsv)
+{
+ struct rb_root *root = &EXT4_SB(sb)->s_rsv_window_root;
+ struct rb_node *node = &rsv->rsv_node;
+ ext4_fsblk_t start = rsv->rsv_start;
+
+ struct rb_node ** p = &root->rb_node;
+ struct rb_node * parent = NULL;
+ struct ext4_reserve_window_node *this;
+
+ while (*p)
+ {
+ parent = *p;
+ this = rb_entry(parent, struct ext4_reserve_window_node, rsv_node);
+
+ if (start < this->rsv_start)
+ p = &(*p)->rb_left;
+ else if (start > this->rsv_end)
+ p = &(*p)->rb_right;
+ else {
+ rsv_window_dump(root, 1);
+ BUG();
+ }
+ }
+
+ rb_link_node(node, parent, p);
+ rb_insert_color(node, root);
+}
+
+/**
+ * ext4_rsv_window_remove() -- unlink a window from the reservation rb tree
+ * @sb: super block
+ * @rsv: reservation window to remove
+ *
+ * Mark the block reservation window as not allocated, and unlink it
+ * from the filesystem reservation window rb tree. Must be called with
+ * rsv_lock hold.
+ */
+static void rsv_window_remove(struct super_block *sb,
+ struct ext4_reserve_window_node *rsv)
+{
+ rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+ rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+ rsv->rsv_alloc_hit = 0;
+ rb_erase(&rsv->rsv_node, &EXT4_SB(sb)->s_rsv_window_root);
+}
+
+/*
+ * rsv_is_empty() -- Check if the reservation window is allocated.
+ * @rsv: given reservation window to check
+ *
+ * returns 1 if the end block is EXT4_RESERVE_WINDOW_NOT_ALLOCATED.
+ */
+static inline int rsv_is_empty(struct ext4_reserve_window *rsv)
+{
+ /* a valid reservation end block could not be 0 */
+ return rsv->_rsv_end == EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+}
+
+/**
+ * ext4_init_block_alloc_info()
+ * @inode: file inode structure
+ *
+ * Allocate and initialize the reservation window structure, and
+ * link the window to the ext4 inode structure at last
+ *
+ * The reservation window structure is only dynamically allocated
+ * and linked to ext4 inode the first time the open file
+ * needs a new block. So, before every ext4_new_block(s) call, for
+ * regular files, we should check whether the reservation window
+ * structure exists or not. In the latter case, this function is called.
+ * Fail to do so will result in block reservation being turned off for that
+ * open file.
+ *
+ * This function is called from ext4_get_blocks_handle(), also called
+ * when setting the reservation window size through ioctl before the file
+ * is open for write (needs block allocation).
+ *
+ * Needs truncate_mutex protection prior to call this function.
+ */
+void ext4_init_block_alloc_info(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
+ struct super_block *sb = inode->i_sb;
+
+ block_i = kmalloc(sizeof(*block_i), GFP_NOFS);
+ if (block_i) {
+ struct ext4_reserve_window_node *rsv = &block_i->rsv_window_node;
+
+ rsv->rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+ rsv->rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+
+ /*
+ * if filesystem is mounted with NORESERVATION, the goal
+ * reservation window size is set to zero to indicate
+ * block reservation is off
+ */
+ if (!test_opt(sb, RESERVATION))
+ rsv->rsv_goal_size = 0;
+ else
+ rsv->rsv_goal_size = EXT4_DEFAULT_RESERVE_BLOCKS;
+ rsv->rsv_alloc_hit = 0;
+ block_i->last_alloc_logical_block = 0;
+ block_i->last_alloc_physical_block = 0;
+ }
+ ei->i_block_alloc_info = block_i;
+}
+
+/**
+ * ext4_discard_reservation()
+ * @inode: inode
+ *
+ * Discard(free) block reservation window on last file close, or truncate
+ * or at last iput().
+ *
+ * It is being called in three cases:
+ * ext4_release_file(): last writer close the file
+ * ext4_clear_inode(): last iput(), when nobody link to this file.
+ * ext4_truncate(): when the block indirect map is about to change.
+ *
+ */
+void ext4_discard_reservation(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_block_alloc_info *block_i = ei->i_block_alloc_info;
+ struct ext4_reserve_window_node *rsv;
+ spinlock_t *rsv_lock = &EXT4_SB(inode->i_sb)->s_rsv_window_lock;
+
+ if (!block_i)
+ return;
+
+ rsv = &block_i->rsv_window_node;
+ if (!rsv_is_empty(&rsv->rsv_window)) {
+ spin_lock(rsv_lock);
+ if (!rsv_is_empty(&rsv->rsv_window))
+ rsv_window_remove(inode->i_sb, rsv);
+ spin_unlock(rsv_lock);
+ }
+}
+
+/**
+ * ext4_free_blocks_sb() -- Free given blocks and update quota
+ * @handle: handle to this transaction
+ * @sb: super block
+ * @block: start physcial block to free
+ * @count: number of blocks to free
+ * @pdquot_freed_blocks: pointer to quota
+ */
+void ext4_free_blocks_sb(handle_t *handle, struct super_block *sb,
+ ext4_fsblk_t block, unsigned long count,
+ unsigned long *pdquot_freed_blocks)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *gd_bh;
+ unsigned long block_group;
+ ext4_grpblk_t bit;
+ unsigned long i;
+ unsigned long overflow;
+ struct ext4_group_desc * desc;
+ struct ext4_super_block * es;
+ struct ext4_sb_info *sbi;
+ int err = 0, ret;
+ ext4_grpblk_t group_freed;
+
+ *pdquot_freed_blocks = 0;
+ sbi = EXT4_SB(sb);
+ es = sbi->s_es;
+ if (block < le32_to_cpu(es->s_first_data_block) ||
+ block + count < block ||
+ block + count > ext4_blocks_count(es)) {
+ ext4_error (sb, "ext4_free_blocks",
+ "Freeing blocks not in datazone - "
+ "block = %llu, count = %lu", block, count);
+ goto error_return;
+ }
+
+ ext4_debug ("freeing block(s) %llu-%llu\n", block, block + count - 1);
+
+do_more:
+ overflow = 0;
+ ext4_get_group_no_and_offset(sb, block, &block_group, &bit);
+ /*
+ * Check to see if we are freeing blocks across a group
+ * boundary.
+ */
+ if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) {
+ overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb);
+ count -= overflow;
+ }
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, block_group);
+ if (!bitmap_bh)
+ goto error_return;
+ desc = ext4_get_group_desc (sb, block_group, &gd_bh);
+ if (!desc)
+ goto error_return;
+
+ if (in_range(ext4_block_bitmap(sb, desc), block, count) ||
+ in_range(ext4_inode_bitmap(sb, desc), block, count) ||
+ in_range(block, ext4_inode_table(sb, desc), sbi->s_itb_per_group) ||
+ in_range(block + count - 1, ext4_inode_table(sb, desc),
+ sbi->s_itb_per_group))
+ ext4_error (sb, "ext4_free_blocks",
+ "Freeing blocks in system zones - "
+ "Block = %llu, count = %lu",
+ block, count);
+
+ /*
+ * We are about to start releasing blocks in the bitmap,
+ * so we need undo access.
+ */
+ /* @@@ check errors */
+ BUFFER_TRACE(bitmap_bh, "getting undo access");
+ err = ext4_journal_get_undo_access(handle, bitmap_bh);
+ if (err)
+ goto error_return;
+
+ /*
+ * We are about to modify some metadata. Call the journal APIs
+ * to unshare ->b_data if a currently-committing transaction is
+ * using it
+ */
+ BUFFER_TRACE(gd_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, gd_bh);
+ if (err)
+ goto error_return;
+
+ jbd_lock_bh_state(bitmap_bh);
+
+ for (i = 0, group_freed = 0; i < count; i++) {
+ /*
+ * An HJ special. This is expensive...
+ */
+#ifdef CONFIG_JBD_DEBUG
+ jbd_unlock_bh_state(bitmap_bh);
+ {
+ struct buffer_head *debug_bh;
+ debug_bh = sb_find_get_block(sb, block + i);
+ if (debug_bh) {
+ BUFFER_TRACE(debug_bh, "Deleted!");
+ if (!bh2jh(bitmap_bh)->b_committed_data)
+ BUFFER_TRACE(debug_bh,
+ "No commited data in bitmap");
+ BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap");
+ __brelse(debug_bh);
+ }
+ }
+ jbd_lock_bh_state(bitmap_bh);
+#endif
+ if (need_resched()) {
+ jbd_unlock_bh_state(bitmap_bh);
+ cond_resched();
+ jbd_lock_bh_state(bitmap_bh);
+ }
+ /* @@@ This prevents newly-allocated data from being
+ * freed and then reallocated within the same
+ * transaction.
+ *
+ * Ideally we would want to allow that to happen, but to
+ * do so requires making jbd2_journal_forget() capable of
+ * revoking the queued write of a data block, which
+ * implies blocking on the journal lock. *forget()
+ * cannot block due to truncate races.
+ *
+ * Eventually we can fix this by making jbd2_journal_forget()
+ * return a status indicating whether or not it was able
+ * to revoke the buffer. On successful revoke, it is
+ * safe not to set the allocation bit in the committed
+ * bitmap, because we know that there is no outstanding
+ * activity on the buffer any more and so it is safe to
+ * reallocate it.
+ */
+ BUFFER_TRACE(bitmap_bh, "set in b_committed_data");
+ J_ASSERT_BH(bitmap_bh,
+ bh2jh(bitmap_bh)->b_committed_data != NULL);
+ ext4_set_bit_atomic(sb_bgl_lock(sbi, block_group), bit + i,
+ bh2jh(bitmap_bh)->b_committed_data);
+
+ /*
+ * We clear the bit in the bitmap after setting the committed
+ * data bit, because this is the reverse order to that which
+ * the allocator uses.
+ */
+ BUFFER_TRACE(bitmap_bh, "clear bit");
+ if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
+ bit + i, bitmap_bh->b_data)) {
+ jbd_unlock_bh_state(bitmap_bh);
+ ext4_error(sb, __FUNCTION__,
+ "bit already cleared for block %llu",
+ (ext4_fsblk_t)(block + i));
+ jbd_lock_bh_state(bitmap_bh);
+ BUFFER_TRACE(bitmap_bh, "bit already cleared");
+ } else {
+ group_freed++;
+ }
+ }
+ jbd_unlock_bh_state(bitmap_bh);
+
+ spin_lock(sb_bgl_lock(sbi, block_group));
+ desc->bg_free_blocks_count =
+ cpu_to_le16(le16_to_cpu(desc->bg_free_blocks_count) +
+ group_freed);
+ spin_unlock(sb_bgl_lock(sbi, block_group));
+ percpu_counter_mod(&sbi->s_freeblocks_counter, count);
+
+ /* We dirtied the bitmap block */
+ BUFFER_TRACE(bitmap_bh, "dirtied bitmap block");
+ err = ext4_journal_dirty_metadata(handle, bitmap_bh);
+
+ /* And the group descriptor block */
+ BUFFER_TRACE(gd_bh, "dirtied group descriptor block");
+ ret = ext4_journal_dirty_metadata(handle, gd_bh);
+ if (!err) err = ret;
+ *pdquot_freed_blocks += group_freed;
+
+ if (overflow && !err) {
+ block += count;
+ count = overflow;
+ goto do_more;
+ }
+ sb->s_dirt = 1;
+error_return:
+ brelse(bitmap_bh);
+ ext4_std_error(sb, err);
+ return;
+}
+
+/**
+ * ext4_free_blocks() -- Free given blocks and update quota
+ * @handle: handle for this transaction
+ * @inode: inode
+ * @block: start physical block to free
+ * @count: number of blocks to count
+ */
+void ext4_free_blocks(handle_t *handle, struct inode *inode,
+ ext4_fsblk_t block, unsigned long count)
+{
+ struct super_block * sb;
+ unsigned long dquot_freed_blocks;
+
+ sb = inode->i_sb;
+ if (!sb) {
+ printk ("ext4_free_blocks: nonexistent device");
+ return;
+ }
+ ext4_free_blocks_sb(handle, sb, block, count, &dquot_freed_blocks);
+ if (dquot_freed_blocks)
+ DQUOT_FREE_BLOCK(inode, dquot_freed_blocks);
+ return;
+}
+
+/**
+ * ext4_test_allocatable()
+ * @nr: given allocation block group
+ * @bh: bufferhead contains the bitmap of the given block group
+ *
+ * For ext4 allocations, we must not reuse any blocks which are
+ * allocated in the bitmap buffer's "last committed data" copy. This
+ * prevents deletes from freeing up the page for reuse until we have
+ * committed the delete transaction.
+ *
+ * If we didn't do this, then deleting something and reallocating it as
+ * data would allow the old block to be overwritten before the
+ * transaction committed (because we force data to disk before commit).
+ * This would lead to corruption if we crashed between overwriting the
+ * data and committing the delete.
+ *
+ * @@@ We may want to make this allocation behaviour conditional on
+ * data-writes at some point, and disable it for metadata allocations or
+ * sync-data inodes.
+ */
+static int ext4_test_allocatable(ext4_grpblk_t nr, struct buffer_head *bh)
+{
+ int ret;
+ struct journal_head *jh = bh2jh(bh);
+
+ if (ext4_test_bit(nr, bh->b_data))
+ return 0;
+
+ jbd_lock_bh_state(bh);
+ if (!jh->b_committed_data)
+ ret = 1;
+ else
+ ret = !ext4_test_bit(nr, jh->b_committed_data);
+ jbd_unlock_bh_state(bh);
+ return ret;
+}
+
+/**
+ * bitmap_search_next_usable_block()
+ * @start: the starting block (group relative) of the search
+ * @bh: bufferhead contains the block group bitmap
+ * @maxblocks: the ending block (group relative) of the reservation
+ *
+ * The bitmap search --- search forward alternately through the actual
+ * bitmap on disk and the last-committed copy in journal, until we find a
+ * bit free in both bitmaps.
+ */
+static ext4_grpblk_t
+bitmap_search_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
+ ext4_grpblk_t maxblocks)
+{
+ ext4_grpblk_t next;
+ struct journal_head *jh = bh2jh(bh);
+
+ while (start < maxblocks) {
+ next = ext4_find_next_zero_bit(bh->b_data, maxblocks, start);
+ if (next >= maxblocks)
+ return -1;
+ if (ext4_test_allocatable(next, bh))
+ return next;
+ jbd_lock_bh_state(bh);
+ if (jh->b_committed_data)
+ start = ext4_find_next_zero_bit(jh->b_committed_data,
+ maxblocks, next);
+ jbd_unlock_bh_state(bh);
+ }
+ return -1;
+}
+
+/**
+ * find_next_usable_block()
+ * @start: the starting block (group relative) to find next
+ * allocatable block in bitmap.
+ * @bh: bufferhead contains the block group bitmap
+ * @maxblocks: the ending block (group relative) for the search
+ *
+ * Find an allocatable block in a bitmap. We honor both the bitmap and
+ * its last-committed copy (if that exists), and perform the "most
+ * appropriate allocation" algorithm of looking for a free block near
+ * the initial goal; then for a free byte somewhere in the bitmap; then
+ * for any free bit in the bitmap.
+ */
+static ext4_grpblk_t
+find_next_usable_block(ext4_grpblk_t start, struct buffer_head *bh,
+ ext4_grpblk_t maxblocks)
+{
+ ext4_grpblk_t here, next;
+ char *p, *r;
+
+ if (start > 0) {
+ /*
+ * The goal was occupied; search forward for a free
+ * block within the next XX blocks.
+ *
+ * end_goal is more or less random, but it has to be
+ * less than EXT4_BLOCKS_PER_GROUP. Aligning up to the
+ * next 64-bit boundary is simple..
+ */
+ ext4_grpblk_t end_goal = (start + 63) & ~63;
+ if (end_goal > maxblocks)
+ end_goal = maxblocks;
+ here = ext4_find_next_zero_bit(bh->b_data, end_goal, start);
+ if (here < end_goal && ext4_test_allocatable(here, bh))
+ return here;
+ ext4_debug("Bit not found near goal\n");
+ }
+
+ here = start;
+ if (here < 0)
+ here = 0;
+
+ p = ((char *)bh->b_data) + (here >> 3);
+ r = memscan(p, 0, (maxblocks - here + 7) >> 3);
+ next = (r - ((char *)bh->b_data)) << 3;
+
+ if (next < maxblocks && next >= start && ext4_test_allocatable(next, bh))
+ return next;
+
+ /*
+ * The bitmap search --- search forward alternately through the actual
+ * bitmap and the last-committed copy until we find a bit free in
+ * both
+ */
+ here = bitmap_search_next_usable_block(here, bh, maxblocks);
+ return here;
+}
+
+/**
+ * claim_block()
+ * @block: the free block (group relative) to allocate
+ * @bh: the bufferhead containts the block group bitmap
+ *
+ * We think we can allocate this block in this bitmap. Try to set the bit.
+ * If that succeeds then check that nobody has allocated and then freed the
+ * block since we saw that is was not marked in b_committed_data. If it _was_
+ * allocated and freed then clear the bit in the bitmap again and return
+ * zero (failure).
+ */
+static inline int
+claim_block(spinlock_t *lock, ext4_grpblk_t block, struct buffer_head *bh)
+{
+ struct journal_head *jh = bh2jh(bh);
+ int ret;
+
+ if (ext4_set_bit_atomic(lock, block, bh->b_data))
+ return 0;
+ jbd_lock_bh_state(bh);
+ if (jh->b_committed_data && ext4_test_bit(block,jh->b_committed_data)) {
+ ext4_clear_bit_atomic(lock, block, bh->b_data);
+ ret = 0;
+ } else {
+ ret = 1;
+ }
+ jbd_unlock_bh_state(bh);
+ return ret;
+}
+
+/**
+ * ext4_try_to_allocate()
+ * @sb: superblock
+ * @handle: handle to this transaction
+ * @group: given allocation block group
+ * @bitmap_bh: bufferhead holds the block bitmap
+ * @grp_goal: given target block within the group
+ * @count: target number of blocks to allocate
+ * @my_rsv: reservation window
+ *
+ * Attempt to allocate blocks within a give range. Set the range of allocation
+ * first, then find the first free bit(s) from the bitmap (within the range),
+ * and at last, allocate the blocks by claiming the found free bit as allocated.
+ *
+ * To set the range of this allocation:
+ * if there is a reservation window, only try to allocate block(s) from the
+ * file's own reservation window;
+ * Otherwise, the allocation range starts from the give goal block, ends at
+ * the block group's last block.
+ *
+ * If we failed to allocate the desired block then we may end up crossing to a
+ * new bitmap. In that case we must release write access to the old one via
+ * ext4_journal_release_buffer(), else we'll run out of credits.
+ */
+static ext4_grpblk_t
+ext4_try_to_allocate(struct super_block *sb, handle_t *handle, int group,
+ struct buffer_head *bitmap_bh, ext4_grpblk_t grp_goal,
+ unsigned long *count, struct ext4_reserve_window *my_rsv)
+{
+ ext4_fsblk_t group_first_block;
+ ext4_grpblk_t start, end;
+ unsigned long num = 0;
+
+ /* we do allocation within the reservation window if we have a window */
+ if (my_rsv) {
+ group_first_block = ext4_group_first_block_no(sb, group);
+ if (my_rsv->_rsv_start >= group_first_block)
+ start = my_rsv->_rsv_start - group_first_block;
+ else
+ /* reservation window cross group boundary */
+ start = 0;
+ end = my_rsv->_rsv_end - group_first_block + 1;
+ if (end > EXT4_BLOCKS_PER_GROUP(sb))
+ /* reservation window crosses group boundary */
+ end = EXT4_BLOCKS_PER_GROUP(sb);
+ if ((start <= grp_goal) && (grp_goal < end))
+ start = grp_goal;
+ else
+ grp_goal = -1;
+ } else {
+ if (grp_goal > 0)
+ start = grp_goal;
+ else
+ start = 0;
+ end = EXT4_BLOCKS_PER_GROUP(sb);
+ }
+
+ BUG_ON(start > EXT4_BLOCKS_PER_GROUP(sb));
+
+repeat:
+ if (grp_goal < 0 || !ext4_test_allocatable(grp_goal, bitmap_bh)) {
+ grp_goal = find_next_usable_block(start, bitmap_bh, end);
+ if (grp_goal < 0)
+ goto fail_access;
+ if (!my_rsv) {
+ int i;
+
+ for (i = 0; i < 7 && grp_goal > start &&
+ ext4_test_allocatable(grp_goal - 1,
+ bitmap_bh);
+ i++, grp_goal--)
+ ;
+ }
+ }
+ start = grp_goal;
+
+ if (!claim_block(sb_bgl_lock(EXT4_SB(sb), group),
+ grp_goal, bitmap_bh)) {
+ /*
+ * The block was allocated by another thread, or it was
+ * allocated and then freed by another thread
+ */
+ start++;
+ grp_goal++;
+ if (start >= end)
+ goto fail_access;
+ goto repeat;
+ }
+ num++;
+ grp_goal++;
+ while (num < *count && grp_goal < end
+ && ext4_test_allocatable(grp_goal, bitmap_bh)
+ && claim_block(sb_bgl_lock(EXT4_SB(sb), group),
+ grp_goal, bitmap_bh)) {
+ num++;
+ grp_goal++;
+ }
+ *count = num;
+ return grp_goal - num;
+fail_access:
+ *count = num;
+ return -1;
+}
+
+/**
+ * find_next_reservable_window():
+ * find a reservable space within the given range.
+ * It does not allocate the reservation window for now:
+ * alloc_new_reservation() will do the work later.
+ *
+ * @search_head: the head of the searching list;
+ * This is not necessarily the list head of the whole filesystem
+ *
+ * We have both head and start_block to assist the search
+ * for the reservable space. The list starts from head,
+ * but we will shift to the place where start_block is,
+ * then start from there, when looking for a reservable space.
+ *
+ * @size: the target new reservation window size
+ *
+ * @group_first_block: the first block we consider to start
+ * the real search from
+ *
+ * @last_block:
+ * the maximum block number that our goal reservable space
+ * could start from. This is normally the last block in this
+ * group. The search will end when we found the start of next
+ * possible reservable space is out of this boundary.
+ * This could handle the cross boundary reservation window
+ * request.
+ *
+ * basically we search from the given range, rather than the whole
+ * reservation double linked list, (start_block, last_block)
+ * to find a free region that is of my size and has not
+ * been reserved.
+ *
+ */
+static int find_next_reservable_window(
+ struct ext4_reserve_window_node *search_head,
+ struct ext4_reserve_window_node *my_rsv,
+ struct super_block * sb,
+ ext4_fsblk_t start_block,
+ ext4_fsblk_t last_block)
+{
+ struct rb_node *next;
+ struct ext4_reserve_window_node *rsv, *prev;
+ ext4_fsblk_t cur;
+ int size = my_rsv->rsv_goal_size;
+
+ /* TODO: make the start of the reservation window byte-aligned */
+ /* cur = *start_block & ~7;*/
+ cur = start_block;
+ rsv = search_head;
+ if (!rsv)
+ return -1;
+
+ while (1) {
+ if (cur <= rsv->rsv_end)
+ cur = rsv->rsv_end + 1;
+
+ /* TODO?
+ * in the case we could not find a reservable space
+ * that is what is expected, during the re-search, we could
+ * remember what's the largest reservable space we could have
+ * and return that one.
+ *
+ * For now it will fail if we could not find the reservable
+ * space with expected-size (or more)...
+ */
+ if (cur > last_block)
+ return -1; /* fail */
+
+ prev = rsv;
+ next = rb_next(&rsv->rsv_node);
+ rsv = list_entry(next,struct ext4_reserve_window_node,rsv_node);
+
+ /*
+ * Reached the last reservation, we can just append to the
+ * previous one.
+ */
+ if (!next)
+ break;
+
+ if (cur + size <= rsv->rsv_start) {
+ /*
+ * Found a reserveable space big enough. We could
+ * have a reservation across the group boundary here
+ */
+ break;
+ }
+ }
+ /*
+ * we come here either :
+ * when we reach the end of the whole list,
+ * and there is empty reservable space after last entry in the list.
+ * append it to the end of the list.
+ *
+ * or we found one reservable space in the middle of the list,
+ * return the reservation window that we could append to.
+ * succeed.
+ */
+
+ if ((prev != my_rsv) && (!rsv_is_empty(&my_rsv->rsv_window)))
+ rsv_window_remove(sb, my_rsv);
+
+ /*
+ * Let's book the whole avaliable window for now. We will check the
+ * disk bitmap later and then, if there are free blocks then we adjust
+ * the window size if it's larger than requested.
+ * Otherwise, we will remove this node from the tree next time
+ * call find_next_reservable_window.
+ */
+ my_rsv->rsv_start = cur;
+ my_rsv->rsv_end = cur + size - 1;
+ my_rsv->rsv_alloc_hit = 0;
+
+ if (prev != my_rsv)
+ ext4_rsv_window_add(sb, my_rsv);
+
+ return 0;
+}
+
+/**
+ * alloc_new_reservation()--allocate a new reservation window
+ *
+ * To make a new reservation, we search part of the filesystem
+ * reservation list (the list that inside the group). We try to
+ * allocate a new reservation window near the allocation goal,
+ * or the beginning of the group, if there is no goal.
+ *
+ * We first find a reservable space after the goal, then from
+ * there, we check the bitmap for the first free block after
+ * it. If there is no free block until the end of group, then the
+ * whole group is full, we failed. Otherwise, check if the free
+ * block is inside the expected reservable space, if so, we
+ * succeed.
+ * If the first free block is outside the reservable space, then
+ * start from the first free block, we search for next available
+ * space, and go on.
+ *
+ * on succeed, a new reservation will be found and inserted into the list
+ * It contains at least one free block, and it does not overlap with other
+ * reservation windows.
+ *
+ * failed: we failed to find a reservation window in this group
+ *
+ * @rsv: the reservation
+ *
+ * @grp_goal: The goal (group-relative). It is where the search for a
+ * free reservable space should start from.
+ * if we have a grp_goal(grp_goal >0 ), then start from there,
+ * no grp_goal(grp_goal = -1), we start from the first block
+ * of the group.
+ *
+ * @sb: the super block
+ * @group: the group we are trying to allocate in
+ * @bitmap_bh: the block group block bitmap
+ *
+ */
+static int alloc_new_reservation(struct ext4_reserve_window_node *my_rsv,
+ ext4_grpblk_t grp_goal, struct super_block *sb,
+ unsigned int group, struct buffer_head *bitmap_bh)
+{
+ struct ext4_reserve_window_node *search_head;
+ ext4_fsblk_t group_first_block, group_end_block, start_block;
+ ext4_grpblk_t first_free_block;
+ struct rb_root *fs_rsv_root = &EXT4_SB(sb)->s_rsv_window_root;
+ unsigned long size;
+ int ret;
+ spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
+
+ group_first_block = ext4_group_first_block_no(sb, group);
+ group_end_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
+
+ if (grp_goal < 0)
+ start_block = group_first_block;
+ else
+ start_block = grp_goal + group_first_block;
+
+ size = my_rsv->rsv_goal_size;
+
+ if (!rsv_is_empty(&my_rsv->rsv_window)) {
+ /*
+ * if the old reservation is cross group boundary
+ * and if the goal is inside the old reservation window,
+ * we will come here when we just failed to allocate from
+ * the first part of the window. We still have another part
+ * that belongs to the next group. In this case, there is no
+ * point to discard our window and try to allocate a new one
+ * in this group(which will fail). we should
+ * keep the reservation window, just simply move on.
+ *
+ * Maybe we could shift the start block of the reservation
+ * window to the first block of next group.
+ */
+
+ if ((my_rsv->rsv_start <= group_end_block) &&
+ (my_rsv->rsv_end > group_end_block) &&
+ (start_block >= my_rsv->rsv_start))
+ return -1;
+
+ if ((my_rsv->rsv_alloc_hit >
+ (my_rsv->rsv_end - my_rsv->rsv_start + 1) / 2)) {
+ /*
+ * if the previously allocation hit ratio is
+ * greater than 1/2, then we double the size of
+ * the reservation window the next time,
+ * otherwise we keep the same size window
+ */
+ size = size * 2;
+ if (size > EXT4_MAX_RESERVE_BLOCKS)
+ size = EXT4_MAX_RESERVE_BLOCKS;
+ my_rsv->rsv_goal_size= size;
+ }
+ }
+
+ spin_lock(rsv_lock);
+ /*
+ * shift the search start to the window near the goal block
+ */
+ search_head = search_reserve_window(fs_rsv_root, start_block);
+
+ /*
+ * find_next_reservable_window() simply finds a reservable window
+ * inside the given range(start_block, group_end_block).
+ *
+ * To make sure the reservation window has a free bit inside it, we
+ * need to check the bitmap after we found a reservable window.
+ */
+retry:
+ ret = find_next_reservable_window(search_head, my_rsv, sb,
+ start_block, group_end_block);
+
+ if (ret == -1) {
+ if (!rsv_is_empty(&my_rsv->rsv_window))
+ rsv_window_remove(sb, my_rsv);
+ spin_unlock(rsv_lock);
+ return -1;
+ }
+
+ /*
+ * On success, find_next_reservable_window() returns the
+ * reservation window where there is a reservable space after it.
+ * Before we reserve this reservable space, we need
+ * to make sure there is at least a free block inside this region.
+ *
+ * searching the first free bit on the block bitmap and copy of
+ * last committed bitmap alternatively, until we found a allocatable
+ * block. Search start from the start block of the reservable space
+ * we just found.
+ */
+ spin_unlock(rsv_lock);
+ first_free_block = bitmap_search_next_usable_block(
+ my_rsv->rsv_start - group_first_block,
+ bitmap_bh, group_end_block - group_first_block + 1);
+
+ if (first_free_block < 0) {
+ /*
+ * no free block left on the bitmap, no point
+ * to reserve the space. return failed.
+ */
+ spin_lock(rsv_lock);
+ if (!rsv_is_empty(&my_rsv->rsv_window))
+ rsv_window_remove(sb, my_rsv);
+ spin_unlock(rsv_lock);
+ return -1; /* failed */
+ }
+
+ start_block = first_free_block + group_first_block;
+ /*
+ * check if the first free block is within the
+ * free space we just reserved
+ */
+ if (start_block >= my_rsv->rsv_start && start_block < my_rsv->rsv_end)
+ return 0; /* success */
+ /*
+ * if the first free bit we found is out of the reservable space
+ * continue search for next reservable space,
+ * start from where the free block is,
+ * we also shift the list head to where we stopped last time
+ */
+ search_head = my_rsv;
+ spin_lock(rsv_lock);
+ goto retry;
+}
+
+/**
+ * try_to_extend_reservation()
+ * @my_rsv: given reservation window
+ * @sb: super block
+ * @size: the delta to extend
+ *
+ * Attempt to expand the reservation window large enough to have
+ * required number of free blocks
+ *
+ * Since ext4_try_to_allocate() will always allocate blocks within
+ * the reservation window range, if the window size is too small,
+ * multiple blocks allocation has to stop at the end of the reservation
+ * window. To make this more efficient, given the total number of
+ * blocks needed and the current size of the window, we try to
+ * expand the reservation window size if necessary on a best-effort
+ * basis before ext4_new_blocks() tries to allocate blocks,
+ */
+static void try_to_extend_reservation(struct ext4_reserve_window_node *my_rsv,
+ struct super_block *sb, int size)
+{
+ struct ext4_reserve_window_node *next_rsv;
+ struct rb_node *next;
+ spinlock_t *rsv_lock = &EXT4_SB(sb)->s_rsv_window_lock;
+
+ if (!spin_trylock(rsv_lock))
+ return;
+
+ next = rb_next(&my_rsv->rsv_node);
+
+ if (!next)
+ my_rsv->rsv_end += size;
+ else {
+ next_rsv = list_entry(next, struct ext4_reserve_window_node, rsv_node);
+
+ if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size)
+ my_rsv->rsv_end += size;
+ else
+ my_rsv->rsv_end = next_rsv->rsv_start - 1;
+ }
+ spin_unlock(rsv_lock);
+}
+
+/**
+ * ext4_try_to_allocate_with_rsv()
+ * @sb: superblock
+ * @handle: handle to this transaction
+ * @group: given allocation block group
+ * @bitmap_bh: bufferhead holds the block bitmap
+ * @grp_goal: given target block within the group
+ * @count: target number of blocks to allocate
+ * @my_rsv: reservation window
+ * @errp: pointer to store the error code
+ *
+ * This is the main function used to allocate a new block and its reservation
+ * window.
+ *
+ * Each time when a new block allocation is need, first try to allocate from
+ * its own reservation. If it does not have a reservation window, instead of
+ * looking for a free bit on bitmap first, then look up the reservation list to
+ * see if it is inside somebody else's reservation window, we try to allocate a
+ * reservation window for it starting from the goal first. Then do the block
+ * allocation within the reservation window.
+ *
+ * This will avoid keeping on searching the reservation list again and
+ * again when somebody is looking for a free block (without
+ * reservation), and there are lots of free blocks, but they are all
+ * being reserved.
+ *
+ * We use a red-black tree for the per-filesystem reservation list.
+ *
+ */
+static ext4_grpblk_t
+ext4_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle,
+ unsigned int group, struct buffer_head *bitmap_bh,
+ ext4_grpblk_t grp_goal,
+ struct ext4_reserve_window_node * my_rsv,
+ unsigned long *count, int *errp)
+{
+ ext4_fsblk_t group_first_block, group_last_block;
+ ext4_grpblk_t ret = 0;
+ int fatal;
+ unsigned long num = *count;
+
+ *errp = 0;
+
+ /*
+ * Make sure we use undo access for the bitmap, because it is critical
+ * that we do the frozen_data COW on bitmap buffers in all cases even
+ * if the buffer is in BJ_Forget state in the committing transaction.
+ */
+ BUFFER_TRACE(bitmap_bh, "get undo access for new block");
+ fatal = ext4_journal_get_undo_access(handle, bitmap_bh);
+ if (fatal) {
+ *errp = fatal;
+ return -1;
+ }
+
+ /*
+ * we don't deal with reservation when
+ * filesystem is mounted without reservation
+ * or the file is not a regular file
+ * or last attempt to allocate a block with reservation turned on failed
+ */
+ if (my_rsv == NULL ) {
+ ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
+ grp_goal, count, NULL);
+ goto out;
+ }
+ /*
+ * grp_goal is a group relative block number (if there is a goal)
+ * 0 < grp_goal < EXT4_BLOCKS_PER_GROUP(sb)
+ * first block is a filesystem wide block number
+ * first block is the block number of the first block in this group
+ */
+ group_first_block = ext4_group_first_block_no(sb, group);
+ group_last_block = group_first_block + (EXT4_BLOCKS_PER_GROUP(sb) - 1);
+
+ /*
+ * Basically we will allocate a new block from inode's reservation
+ * window.
+ *
+ * We need to allocate a new reservation window, if:
+ * a) inode does not have a reservation window; or
+ * b) last attempt to allocate a block from existing reservation
+ * failed; or
+ * c) we come here with a goal and with a reservation window
+ *
+ * We do not need to allocate a new reservation window if we come here
+ * at the beginning with a goal and the goal is inside the window, or
+ * we don't have a goal but already have a reservation window.
+ * then we could go to allocate from the reservation window directly.
+ */
+ while (1) {
+ if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) ||
+ !goal_in_my_reservation(&my_rsv->rsv_window,
+ grp_goal, group, sb)) {
+ if (my_rsv->rsv_goal_size < *count)
+ my_rsv->rsv_goal_size = *count;
+ ret = alloc_new_reservation(my_rsv, grp_goal, sb,
+ group, bitmap_bh);
+ if (ret < 0)
+ break; /* failed */
+
+ if (!goal_in_my_reservation(&my_rsv->rsv_window,
+ grp_goal, group, sb))
+ grp_goal = -1;
+ } else if (grp_goal > 0 &&
+ (my_rsv->rsv_end-grp_goal+1) < *count)
+ try_to_extend_reservation(my_rsv, sb,
+ *count-my_rsv->rsv_end + grp_goal - 1);
+
+ if ((my_rsv->rsv_start > group_last_block) ||
+ (my_rsv->rsv_end < group_first_block)) {
+ rsv_window_dump(&EXT4_SB(sb)->s_rsv_window_root, 1);
+ BUG();
+ }
+ ret = ext4_try_to_allocate(sb, handle, group, bitmap_bh,
+ grp_goal, &num, &my_rsv->rsv_window);
+ if (ret >= 0) {
+ my_rsv->rsv_alloc_hit += num;
+ *count = num;
+ break; /* succeed */
+ }
+ num = *count;
+ }
+out:
+ if (ret >= 0) {
+ BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for "
+ "bitmap block");
+ fatal = ext4_journal_dirty_metadata(handle, bitmap_bh);
+ if (fatal) {
+ *errp = fatal;
+ return -1;
+ }
+ return ret;
+ }
+
+ BUFFER_TRACE(bitmap_bh, "journal_release_buffer");
+ ext4_journal_release_buffer(handle, bitmap_bh);
+ return ret;
+}
+
+/**
+ * ext4_has_free_blocks()
+ * @sbi: in-core super block structure.
+ *
+ * Check if filesystem has at least 1 free block available for allocation.
+ */
+static int ext4_has_free_blocks(struct ext4_sb_info *sbi)
+{
+ ext4_fsblk_t free_blocks, root_blocks;
+
+ free_blocks = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
+ root_blocks = ext4_r_blocks_count(sbi->s_es);
+ if (free_blocks < root_blocks + 1 && !capable(CAP_SYS_RESOURCE) &&
+ sbi->s_resuid != current->fsuid &&
+ (sbi->s_resgid == 0 || !in_group_p (sbi->s_resgid))) {
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * ext4_should_retry_alloc()
+ * @sb: super block
+ * @retries number of attemps has been made
+ *
+ * ext4_should_retry_alloc() is called when ENOSPC is returned, and if
+ * it is profitable to retry the operation, this function will wait
+ * for the current or commiting transaction to complete, and then
+ * return TRUE.
+ *
+ * if the total number of retries exceed three times, return FALSE.
+ */
+int ext4_should_retry_alloc(struct super_block *sb, int *retries)
+{
+ if (!ext4_has_free_blocks(EXT4_SB(sb)) || (*retries)++ > 3)
+ return 0;
+
+ jbd_debug(1, "%s: retrying operation after ENOSPC\n", sb->s_id);
+
+ return jbd2_journal_force_commit_nested(EXT4_SB(sb)->s_journal);
+}
+
+/**
+ * ext4_new_blocks() -- core block(s) allocation function
+ * @handle: handle to this transaction
+ * @inode: file inode
+ * @goal: given target block(filesystem wide)
+ * @count: target number of blocks to allocate
+ * @errp: error code
+ *
+ * ext4_new_blocks uses a goal block to assist allocation. It tries to
+ * allocate block(s) from the block group contains the goal block first. If that
+ * fails, it will try to allocate block(s) from other block groups without
+ * any specific goal block.
+ *
+ */
+ext4_fsblk_t ext4_new_blocks(handle_t *handle, struct inode *inode,
+ ext4_fsblk_t goal, unsigned long *count, int *errp)
+{
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *gdp_bh;
+ unsigned long group_no;
+ int goal_group;
+ ext4_grpblk_t grp_target_blk; /* blockgroup relative goal block */
+ ext4_grpblk_t grp_alloc_blk; /* blockgroup-relative allocated block*/
+ ext4_fsblk_t ret_block; /* filesyetem-wide allocated block */
+ int bgi; /* blockgroup iteration index */
+ int fatal = 0, err;
+ int performed_allocation = 0;
+ ext4_grpblk_t free_blocks; /* number of free blocks in a group */
+ struct super_block *sb;
+ struct ext4_group_desc *gdp;
+ struct ext4_super_block *es;
+ struct ext4_sb_info *sbi;
+ struct ext4_reserve_window_node *my_rsv = NULL;
+ struct ext4_block_alloc_info *block_i;
+ unsigned short windowsz = 0;
+#ifdef EXT4FS_DEBUG
+ static int goal_hits, goal_attempts;
+#endif
+ unsigned long ngroups;
+ unsigned long num = *count;
+
+ *errp = -ENOSPC;
+ sb = inode->i_sb;
+ if (!sb) {
+ printk("ext4_new_block: nonexistent device");
+ return 0;
+ }
+
+ /*
+ * Check quota for allocation of this block.
+ */
+ if (DQUOT_ALLOC_BLOCK(inode, num)) {
+ *errp = -EDQUOT;
+ return 0;
+ }
+
+ sbi = EXT4_SB(sb);
+ es = EXT4_SB(sb)->s_es;
+ ext4_debug("goal=%lu.\n", goal);
+ /*
+ * Allocate a block from reservation only when
+ * filesystem is mounted with reservation(default,-o reservation), and
+ * it's a regular file, and
+ * the desired window size is greater than 0 (One could use ioctl
+ * command EXT4_IOC_SETRSVSZ to set the window size to 0 to turn off
+ * reservation on that particular file)
+ */
+ block_i = EXT4_I(inode)->i_block_alloc_info;
+ if (block_i && ((windowsz = block_i->rsv_window_node.rsv_goal_size) > 0))
+ my_rsv = &block_i->rsv_window_node;
+
+ if (!ext4_has_free_blocks(sbi)) {
+ *errp = -ENOSPC;
+ goto out;
+ }
+
+ /*
+ * First, test whether the goal block is free.
+ */
+ if (goal < le32_to_cpu(es->s_first_data_block) ||
+ goal >= ext4_blocks_count(es))
+ goal = le32_to_cpu(es->s_first_data_block);
+ ext4_get_group_no_and_offset(sb, goal, &group_no, &grp_target_blk);
+ goal_group = group_no;
+retry_alloc:
+ gdp = ext4_get_group_desc(sb, group_no, &gdp_bh);
+ if (!gdp)
+ goto io_error;
+
+ free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
+ /*
+ * if there is not enough free blocks to make a new resevation
+ * turn off reservation for this allocation
+ */
+ if (my_rsv && (free_blocks < windowsz)
+ && (rsv_is_empty(&my_rsv->rsv_window)))
+ my_rsv = NULL;
+
+ if (free_blocks > 0) {
+ bitmap_bh = read_block_bitmap(sb, group_no);
+ if (!bitmap_bh)
+ goto io_error;
+ grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
+ group_no, bitmap_bh, grp_target_blk,
+ my_rsv, &num, &fatal);
+ if (fatal)
+ goto out;
+ if (grp_alloc_blk >= 0)
+ goto allocated;
+ }
+
+ ngroups = EXT4_SB(sb)->s_groups_count;
+ smp_rmb();
+
+ /*
+ * Now search the rest of the groups. We assume that
+ * i and gdp correctly point to the last group visited.
+ */
+ for (bgi = 0; bgi < ngroups; bgi++) {
+ group_no++;
+ if (group_no >= ngroups)
+ group_no = 0;
+ gdp = ext4_get_group_desc(sb, group_no, &gdp_bh);
+ if (!gdp) {
+ *errp = -EIO;
+ goto out;
+ }
+ free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
+ /*
+ * skip this group if the number of
+ * free blocks is less than half of the reservation
+ * window size.
+ */
+ if (free_blocks <= (windowsz/2))
+ continue;
+
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, group_no);
+ if (!bitmap_bh)
+ goto io_error;
+ /*
+ * try to allocate block(s) from this group, without a goal(-1).
+ */
+ grp_alloc_blk = ext4_try_to_allocate_with_rsv(sb, handle,
+ group_no, bitmap_bh, -1, my_rsv,
+ &num, &fatal);
+ if (fatal)
+ goto out;
+ if (grp_alloc_blk >= 0)
+ goto allocated;
+ }
+ /*
+ * We may end up a bogus ealier ENOSPC error due to
+ * filesystem is "full" of reservations, but
+ * there maybe indeed free blocks avaliable on disk
+ * In this case, we just forget about the reservations
+ * just do block allocation as without reservations.
+ */
+ if (my_rsv) {
+ my_rsv = NULL;
+ group_no = goal_group;
+ goto retry_alloc;
+ }
+ /* No space left on the device */
+ *errp = -ENOSPC;
+ goto out;
+
+allocated:
+
+ ext4_debug("using block group %d(%d)\n",
+ group_no, gdp->bg_free_blocks_count);
+
+ BUFFER_TRACE(gdp_bh, "get_write_access");
+ fatal = ext4_journal_get_write_access(handle, gdp_bh);
+ if (fatal)
+ goto out;
+
+ ret_block = grp_alloc_blk + ext4_group_first_block_no(sb, group_no);
+
+ if (in_range(ext4_block_bitmap(sb, gdp), ret_block, num) ||
+ in_range(ext4_block_bitmap(sb, gdp), ret_block, num) ||
+ in_range(ret_block, ext4_inode_table(sb, gdp),
+ EXT4_SB(sb)->s_itb_per_group) ||
+ in_range(ret_block + num - 1, ext4_inode_table(sb, gdp),
+ EXT4_SB(sb)->s_itb_per_group))
+ ext4_error(sb, "ext4_new_block",
+ "Allocating block in system zone - "
+ "blocks from %llu, length %lu",
+ ret_block, num);
+
+ performed_allocation = 1;
+
+#ifdef CONFIG_JBD_DEBUG
+ {
+ struct buffer_head *debug_bh;
+
+ /* Record bitmap buffer state in the newly allocated block */
+ debug_bh = sb_find_get_block(sb, ret_block);
+ if (debug_bh) {
+ BUFFER_TRACE(debug_bh, "state when allocated");
+ BUFFER_TRACE2(debug_bh, bitmap_bh, "bitmap state");
+ brelse(debug_bh);
+ }
+ }
+ jbd_lock_bh_state(bitmap_bh);
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data) {
+ int i;
+
+ for (i = 0; i < num; i++) {
+ if (ext4_test_bit(grp_alloc_blk+i,
+ bh2jh(bitmap_bh)->b_committed_data)) {
+ printk("%s: block was unexpectedly set in "
+ "b_committed_data\n", __FUNCTION__);
+ }
+ }
+ }
+ ext4_debug("found bit %d\n", grp_alloc_blk);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ jbd_unlock_bh_state(bitmap_bh);
+#endif
+
+ if (ret_block + num - 1 >= ext4_blocks_count(es)) {
+ ext4_error(sb, "ext4_new_block",
+ "block(%llu) >= blocks count(%llu) - "
+ "block_group = %lu, es == %p ", ret_block,
+ ext4_blocks_count(es), group_no, es);
+ goto out;
+ }
+
+ /*
+ * It is up to the caller to add the new buffer to a journal
+ * list of some description. We don't know in advance whether
+ * the caller wants to use it as metadata or data.
+ */
+ ext4_debug("allocating block %lu. Goal hits %d of %d.\n",
+ ret_block, goal_hits, goal_attempts);
+
+ spin_lock(sb_bgl_lock(sbi, group_no));
+ gdp->bg_free_blocks_count =
+ cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count)-num);
+ spin_unlock(sb_bgl_lock(sbi, group_no));
+ percpu_counter_mod(&sbi->s_freeblocks_counter, -num);
+
+ BUFFER_TRACE(gdp_bh, "journal_dirty_metadata for group descriptor");
+ err = ext4_journal_dirty_metadata(handle, gdp_bh);
+ if (!fatal)
+ fatal = err;
+
+ sb->s_dirt = 1;
+ if (fatal)
+ goto out;
+
+ *errp = 0;
+ brelse(bitmap_bh);
+ DQUOT_FREE_BLOCK(inode, *count-num);
+ *count = num;
+ return ret_block;
+
+io_error:
+ *errp = -EIO;
+out:
+ if (fatal) {
+ *errp = fatal;
+ ext4_std_error(sb, fatal);
+ }
+ /*
+ * Undo the block allocation
+ */
+ if (!performed_allocation)
+ DQUOT_FREE_BLOCK(inode, *count);
+ brelse(bitmap_bh);
+ return 0;
+}
+
+ext4_fsblk_t ext4_new_block(handle_t *handle, struct inode *inode,
+ ext4_fsblk_t goal, int *errp)
+{
+ unsigned long count = 1;
+
+ return ext4_new_blocks(handle, inode, goal, &count, errp);
+}
+
+/**
+ * ext4_count_free_blocks() -- count filesystem free blocks
+ * @sb: superblock
+ *
+ * Adds up the number of free blocks from each block group.
+ */
+ext4_fsblk_t ext4_count_free_blocks(struct super_block *sb)
+{
+ ext4_fsblk_t desc_count;
+ struct ext4_group_desc *gdp;
+ int i;
+ unsigned long ngroups = EXT4_SB(sb)->s_groups_count;
+#ifdef EXT4FS_DEBUG
+ struct ext4_super_block *es;
+ ext4_fsblk_t bitmap_count;
+ unsigned long x;
+ struct buffer_head *bitmap_bh = NULL;
+
+ es = EXT4_SB(sb)->s_es;
+ desc_count = 0;
+ bitmap_count = 0;
+ gdp = NULL;
+
+ smp_rmb();
+ for (i = 0; i < ngroups; i++) {
+ gdp = ext4_get_group_desc(sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += le16_to_cpu(gdp->bg_free_blocks_count);
+ brelse(bitmap_bh);
+ bitmap_bh = read_block_bitmap(sb, i);
+ if (bitmap_bh == NULL)
+ continue;
+
+ x = ext4_count_free(bitmap_bh, sb->s_blocksize);
+ printk("group %d: stored = %d, counted = %lu\n",
+ i, le16_to_cpu(gdp->bg_free_blocks_count), x);
+ bitmap_count += x;
+ }
+ brelse(bitmap_bh);
+ printk("ext4_count_free_blocks: stored = %llu"
+ ", computed = %llu, %llu\n",
+ EXT4_FREE_BLOCKS_COUNT(es),
+ desc_count, bitmap_count);
+ return bitmap_count;
+#else
+ desc_count = 0;
+ smp_rmb();
+ for (i = 0; i < ngroups; i++) {
+ gdp = ext4_get_group_desc(sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += le16_to_cpu(gdp->bg_free_blocks_count);
+ }
+
+ return desc_count;
+#endif
+}
+
+static inline int
+block_in_use(ext4_fsblk_t block, struct super_block *sb, unsigned char *map)
+{
+ ext4_grpblk_t offset;
+
+ ext4_get_group_no_and_offset(sb, block, NULL, &offset);
+ return ext4_test_bit (offset, map);
+}
+
+static inline int test_root(int a, int b)
+{
+ int num = b;
+
+ while (a > num)
+ num *= b;
+ return num == a;
+}
+
+static int ext4_group_sparse(int group)
+{
+ if (group <= 1)
+ return 1;
+ if (!(group & 1))
+ return 0;
+ return (test_root(group, 7) || test_root(group, 5) ||
+ test_root(group, 3));
+}
+
+/**
+ * ext4_bg_has_super - number of blocks used by the superblock in group
+ * @sb: superblock for filesystem
+ * @group: group number to check
+ *
+ * Return the number of blocks used by the superblock (primary or backup)
+ * in this group. Currently this will be only 0 or 1.
+ */
+int ext4_bg_has_super(struct super_block *sb, int group)
+{
+ if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
+ !ext4_group_sparse(group))
+ return 0;
+ return 1;
+}
+
+static unsigned long ext4_bg_num_gdb_meta(struct super_block *sb, int group)
+{
+ unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
+ unsigned long first = metagroup * EXT4_DESC_PER_BLOCK(sb);
+ unsigned long last = first + EXT4_DESC_PER_BLOCK(sb) - 1;
+
+ if (group == first || group == first + 1 || group == last)
+ return 1;
+ return 0;
+}
+
+static unsigned long ext4_bg_num_gdb_nometa(struct super_block *sb, int group)
+{
+ if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
+ !ext4_group_sparse(group))
+ return 0;
+ return EXT4_SB(sb)->s_gdb_count;
+}
+
+/**
+ * ext4_bg_num_gdb - number of blocks used by the group table in group
+ * @sb: superblock for filesystem
+ * @group: group number to check
+ *
+ * Return the number of blocks used by the group descriptor table
+ * (primary or backup) in this group. In the future there may be a
+ * different number of descriptor blocks in each group.
+ */
+unsigned long ext4_bg_num_gdb(struct super_block *sb, int group)
+{
+ unsigned long first_meta_bg =
+ le32_to_cpu(EXT4_SB(sb)->s_es->s_first_meta_bg);
+ unsigned long metagroup = group / EXT4_DESC_PER_BLOCK(sb);
+
+ if (!EXT4_HAS_INCOMPAT_FEATURE(sb,EXT4_FEATURE_INCOMPAT_META_BG) ||
+ metagroup < first_meta_bg)
+ return ext4_bg_num_gdb_nometa(sb,group);
+
+ return ext4_bg_num_gdb_meta(sb,group);
+
+}
diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c
new file mode 100644
index 000000000000..11e93c169bcf
--- /dev/null
+++ b/fs/ext4/bitmap.c
@@ -0,0 +1,32 @@
+/*
+ * linux/fs/ext4/bitmap.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ */
+
+#include <linux/buffer_head.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+
+#ifdef EXT4FS_DEBUG
+
+static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
+
+unsigned long ext4_count_free (struct buffer_head * map, unsigned int numchars)
+{
+ unsigned int i;
+ unsigned long sum = 0;
+
+ if (!map)
+ return (0);
+ for (i = 0; i < numchars; i++)
+ sum += nibblemap[map->b_data[i] & 0xf] +
+ nibblemap[(map->b_data[i] >> 4) & 0xf];
+ return (sum);
+}
+
+#endif /* EXT4FS_DEBUG */
+
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
new file mode 100644
index 000000000000..f8595787a70e
--- /dev/null
+++ b/fs/ext4/dir.c
@@ -0,0 +1,518 @@
+/*
+ * linux/fs/ext4/dir.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/dir.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * ext4 directory handling functions
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ *
+ * Hash Tree Directory indexing (c) 2001 Daniel Phillips
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/buffer_head.h>
+#include <linux/smp_lock.h>
+#include <linux/slab.h>
+#include <linux/rbtree.h>
+
+static unsigned char ext4_filetype_table[] = {
+ DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
+};
+
+static int ext4_readdir(struct file *, void *, filldir_t);
+static int ext4_dx_readdir(struct file * filp,
+ void * dirent, filldir_t filldir);
+static int ext4_release_dir (struct inode * inode,
+ struct file * filp);
+
+const struct file_operations ext4_dir_operations = {
+ .llseek = generic_file_llseek,
+ .read = generic_read_dir,
+ .readdir = ext4_readdir, /* we take BKL. needed?*/
+ .ioctl = ext4_ioctl, /* BKL held */
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ext4_compat_ioctl,
+#endif
+ .fsync = ext4_sync_file, /* BKL held */
+#ifdef CONFIG_EXT4_INDEX
+ .release = ext4_release_dir,
+#endif
+};
+
+
+static unsigned char get_dtype(struct super_block *sb, int filetype)
+{
+ if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE) ||
+ (filetype >= EXT4_FT_MAX))
+ return DT_UNKNOWN;
+
+ return (ext4_filetype_table[filetype]);
+}
+
+
+int ext4_check_dir_entry (const char * function, struct inode * dir,
+ struct ext4_dir_entry_2 * de,
+ struct buffer_head * bh,
+ unsigned long offset)
+{
+ const char * error_msg = NULL;
+ const int rlen = le16_to_cpu(de->rec_len);
+
+ if (rlen < EXT4_DIR_REC_LEN(1))
+ error_msg = "rec_len is smaller than minimal";
+ else if (rlen % 4 != 0)
+ error_msg = "rec_len % 4 != 0";
+ else if (rlen < EXT4_DIR_REC_LEN(de->name_len))
+ error_msg = "rec_len is too small for name_len";
+ else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
+ error_msg = "directory entry across blocks";
+ else if (le32_to_cpu(de->inode) >
+ le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))
+ error_msg = "inode out of bounds";
+
+ if (error_msg != NULL)
+ ext4_error (dir->i_sb, function,
+ "bad entry in directory #%lu: %s - "
+ "offset=%lu, inode=%lu, rec_len=%d, name_len=%d",
+ dir->i_ino, error_msg, offset,
+ (unsigned long) le32_to_cpu(de->inode),
+ rlen, de->name_len);
+ return error_msg == NULL ? 1 : 0;
+}
+
+static int ext4_readdir(struct file * filp,
+ void * dirent, filldir_t filldir)
+{
+ int error = 0;
+ unsigned long offset;
+ int i, stored;
+ struct ext4_dir_entry_2 *de;
+ struct super_block *sb;
+ int err;
+ struct inode *inode = filp->f_dentry->d_inode;
+ int ret = 0;
+
+ sb = inode->i_sb;
+
+#ifdef CONFIG_EXT4_INDEX
+ if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_COMPAT_DIR_INDEX) &&
+ ((EXT4_I(inode)->i_flags & EXT4_INDEX_FL) ||
+ ((inode->i_size >> sb->s_blocksize_bits) == 1))) {
+ err = ext4_dx_readdir(filp, dirent, filldir);
+ if (err != ERR_BAD_DX_DIR) {
+ ret = err;
+ goto out;
+ }
+ /*
+ * We don't set the inode dirty flag since it's not
+ * critical that it get flushed back to the disk.
+ */
+ EXT4_I(filp->f_dentry->d_inode)->i_flags &= ~EXT4_INDEX_FL;
+ }
+#endif
+ stored = 0;
+ offset = filp->f_pos & (sb->s_blocksize - 1);
+
+ while (!error && !stored && filp->f_pos < inode->i_size) {
+ unsigned long blk = filp->f_pos >> EXT4_BLOCK_SIZE_BITS(sb);
+ struct buffer_head map_bh;
+ struct buffer_head *bh = NULL;
+
+ map_bh.b_state = 0;
+ err = ext4_get_blocks_wrap(NULL, inode, blk, 1, &map_bh, 0, 0);
+ if (err > 0) {
+ page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
+ &filp->f_ra,
+ filp,
+ map_bh.b_blocknr >>
+ (PAGE_CACHE_SHIFT - inode->i_blkbits),
+ 1);
+ bh = ext4_bread(NULL, inode, blk, 0, &err);
+ }
+
+ /*
+ * We ignore I/O errors on directories so users have a chance
+ * of recovering data when there's a bad sector
+ */
+ if (!bh) {
+ ext4_error (sb, "ext4_readdir",
+ "directory #%lu contains a hole at offset %lu",
+ inode->i_ino, (unsigned long)filp->f_pos);
+ filp->f_pos += sb->s_blocksize - offset;
+ continue;
+ }
+
+revalidate:
+ /* If the dir block has changed since the last call to
+ * readdir(2), then we might be pointing to an invalid
+ * dirent right now. Scan from the start of the block
+ * to make sure. */
+ if (filp->f_version != inode->i_version) {
+ for (i = 0; i < sb->s_blocksize && i < offset; ) {
+ de = (struct ext4_dir_entry_2 *)
+ (bh->b_data + i);
+ /* It's too expensive to do a full
+ * dirent test each time round this
+ * loop, but we do have to test at
+ * least that it is non-zero. A
+ * failure will be detected in the
+ * dirent test below. */
+ if (le16_to_cpu(de->rec_len) <
+ EXT4_DIR_REC_LEN(1))
+ break;
+ i += le16_to_cpu(de->rec_len);
+ }
+ offset = i;
+ filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
+ | offset;
+ filp->f_version = inode->i_version;
+ }
+
+ while (!error && filp->f_pos < inode->i_size
+ && offset < sb->s_blocksize) {
+ de = (struct ext4_dir_entry_2 *) (bh->b_data + offset);
+ if (!ext4_check_dir_entry ("ext4_readdir", inode, de,
+ bh, offset)) {
+ /*
+ * On error, skip the f_pos to the next block
+ */
+ filp->f_pos = (filp->f_pos |
+ (sb->s_blocksize - 1)) + 1;
+ brelse (bh);
+ ret = stored;
+ goto out;
+ }
+ offset += le16_to_cpu(de->rec_len);
+ if (le32_to_cpu(de->inode)) {
+ /* We might block in the next section
+ * if the data destination is
+ * currently swapped out. So, use a
+ * version stamp to detect whether or
+ * not the directory has been modified
+ * during the copy operation.
+ */
+ unsigned long version = filp->f_version;
+
+ error = filldir(dirent, de->name,
+ de->name_len,
+ filp->f_pos,
+ le32_to_cpu(de->inode),
+ get_dtype(sb, de->file_type));
+ if (error)
+ break;
+ if (version != filp->f_version)
+ goto revalidate;
+ stored ++;
+ }
+ filp->f_pos += le16_to_cpu(de->rec_len);
+ }
+ offset = 0;
+ brelse (bh);
+ }
+out:
+ return ret;
+}
+
+#ifdef CONFIG_EXT4_INDEX
+/*
+ * These functions convert from the major/minor hash to an f_pos
+ * value.
+ *
+ * Currently we only use major hash numer. This is unfortunate, but
+ * on 32-bit machines, the same VFS interface is used for lseek and
+ * llseek, so if we use the 64 bit offset, then the 32-bit versions of
+ * lseek/telldir/seekdir will blow out spectacularly, and from within
+ * the ext2 low-level routine, we don't know if we're being called by
+ * a 64-bit version of the system call or the 32-bit version of the
+ * system call. Worse yet, NFSv2 only allows for a 32-bit readdir
+ * cookie. Sigh.
+ */
+#define hash2pos(major, minor) (major >> 1)
+#define pos2maj_hash(pos) ((pos << 1) & 0xffffffff)
+#define pos2min_hash(pos) (0)
+
+/*
+ * This structure holds the nodes of the red-black tree used to store
+ * the directory entry in hash order.
+ */
+struct fname {
+ __u32 hash;
+ __u32 minor_hash;
+ struct rb_node rb_hash;
+ struct fname *next;
+ __u32 inode;
+ __u8 name_len;
+ __u8 file_type;
+ char name[0];
+};
+
+/*
+ * This functoin implements a non-recursive way of freeing all of the
+ * nodes in the red-black tree.
+ */
+static void free_rb_tree_fname(struct rb_root *root)
+{
+ struct rb_node *n = root->rb_node;
+ struct rb_node *parent;
+ struct fname *fname;
+
+ while (n) {
+ /* Do the node's children first */
+ if ((n)->rb_left) {
+ n = n->rb_left;
+ continue;
+ }
+ if (n->rb_right) {
+ n = n->rb_right;
+ continue;
+ }
+ /*
+ * The node has no children; free it, and then zero
+ * out parent's link to it. Finally go to the
+ * beginning of the loop and try to free the parent
+ * node.
+ */
+ parent = rb_parent(n);
+ fname = rb_entry(n, struct fname, rb_hash);
+ while (fname) {
+ struct fname * old = fname;
+ fname = fname->next;
+ kfree (old);
+ }
+ if (!parent)
+ root->rb_node = NULL;
+ else if (parent->rb_left == n)
+ parent->rb_left = NULL;
+ else if (parent->rb_right == n)
+ parent->rb_right = NULL;
+ n = parent;
+ }
+ root->rb_node = NULL;
+}
+
+
+static struct dir_private_info *create_dir_info(loff_t pos)
+{
+ struct dir_private_info *p;
+
+ p = kmalloc(sizeof(struct dir_private_info), GFP_KERNEL);
+ if (!p)
+ return NULL;
+ p->root.rb_node = NULL;
+ p->curr_node = NULL;
+ p->extra_fname = NULL;
+ p->last_pos = 0;
+ p->curr_hash = pos2maj_hash(pos);
+ p->curr_minor_hash = pos2min_hash(pos);
+ p->next_hash = 0;
+ return p;
+}
+
+void ext4_htree_free_dir_info(struct dir_private_info *p)
+{
+ free_rb_tree_fname(&p->root);
+ kfree(p);
+}
+
+/*
+ * Given a directory entry, enter it into the fname rb tree.
+ */
+int ext4_htree_store_dirent(struct file *dir_file, __u32 hash,
+ __u32 minor_hash,
+ struct ext4_dir_entry_2 *dirent)
+{
+ struct rb_node **p, *parent = NULL;
+ struct fname * fname, *new_fn;
+ struct dir_private_info *info;
+ int len;
+
+ info = (struct dir_private_info *) dir_file->private_data;
+ p = &info->root.rb_node;
+
+ /* Create and allocate the fname structure */
+ len = sizeof(struct fname) + dirent->name_len + 1;
+ new_fn = kzalloc(len, GFP_KERNEL);
+ if (!new_fn)
+ return -ENOMEM;
+ new_fn->hash = hash;
+ new_fn->minor_hash = minor_hash;
+ new_fn->inode = le32_to_cpu(dirent->inode);
+ new_fn->name_len = dirent->name_len;
+ new_fn->file_type = dirent->file_type;
+ memcpy(new_fn->name, dirent->name, dirent->name_len);
+ new_fn->name[dirent->name_len] = 0;
+
+ while (*p) {
+ parent = *p;
+ fname = rb_entry(parent, struct fname, rb_hash);
+
+ /*
+ * If the hash and minor hash match up, then we put
+ * them on a linked list. This rarely happens...
+ */
+ if ((new_fn->hash == fname->hash) &&
+ (new_fn->minor_hash == fname->minor_hash)) {
+ new_fn->next = fname->next;
+ fname->next = new_fn;
+ return 0;
+ }
+
+ if (new_fn->hash < fname->hash)
+ p = &(*p)->rb_left;
+ else if (new_fn->hash > fname->hash)
+ p = &(*p)->rb_right;
+ else if (new_fn->minor_hash < fname->minor_hash)
+ p = &(*p)->rb_left;
+ else /* if (new_fn->minor_hash > fname->minor_hash) */
+ p = &(*p)->rb_right;
+ }
+
+ rb_link_node(&new_fn->rb_hash, parent, p);
+ rb_insert_color(&new_fn->rb_hash, &info->root);
+ return 0;
+}
+
+
+
+/*
+ * This is a helper function for ext4_dx_readdir. It calls filldir
+ * for all entres on the fname linked list. (Normally there is only
+ * one entry on the linked list, unless there are 62 bit hash collisions.)
+ */
+static int call_filldir(struct file * filp, void * dirent,
+ filldir_t filldir, struct fname *fname)
+{
+ struct dir_private_info *info = filp->private_data;
+ loff_t curr_pos;
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct super_block * sb;
+ int error;
+
+ sb = inode->i_sb;
+
+ if (!fname) {
+ printk("call_filldir: called with null fname?!?\n");
+ return 0;
+ }
+ curr_pos = hash2pos(fname->hash, fname->minor_hash);
+ while (fname) {
+ error = filldir(dirent, fname->name,
+ fname->name_len, curr_pos,
+ fname->inode,
+ get_dtype(sb, fname->file_type));
+ if (error) {
+ filp->f_pos = curr_pos;
+ info->extra_fname = fname->next;
+ return error;
+ }
+ fname = fname->next;
+ }
+ return 0;
+}
+
+static int ext4_dx_readdir(struct file * filp,
+ void * dirent, filldir_t filldir)
+{
+ struct dir_private_info *info = filp->private_data;
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct fname *fname;
+ int ret;
+
+ if (!info) {
+ info = create_dir_info(filp->f_pos);
+ if (!info)
+ return -ENOMEM;
+ filp->private_data = info;
+ }
+
+ if (filp->f_pos == EXT4_HTREE_EOF)
+ return 0; /* EOF */
+
+ /* Some one has messed with f_pos; reset the world */
+ if (info->last_pos != filp->f_pos) {
+ free_rb_tree_fname(&info->root);
+ info->curr_node = NULL;
+ info->extra_fname = NULL;
+ info->curr_hash = pos2maj_hash(filp->f_pos);
+ info->curr_minor_hash = pos2min_hash(filp->f_pos);
+ }
+
+ /*
+ * If there are any leftover names on the hash collision
+ * chain, return them first.
+ */
+ if (info->extra_fname &&
+ call_filldir(filp, dirent, filldir, info->extra_fname))
+ goto finished;
+
+ if (!info->curr_node)
+ info->curr_node = rb_first(&info->root);
+
+ while (1) {
+ /*
+ * Fill the rbtree if we have no more entries,
+ * or the inode has changed since we last read in the
+ * cached entries.
+ */
+ if ((!info->curr_node) ||
+ (filp->f_version != inode->i_version)) {
+ info->curr_node = NULL;
+ free_rb_tree_fname(&info->root);
+ filp->f_version = inode->i_version;
+ ret = ext4_htree_fill_tree(filp, info->curr_hash,
+ info->curr_minor_hash,
+ &info->next_hash);
+ if (ret < 0)
+ return ret;
+ if (ret == 0) {
+ filp->f_pos = EXT4_HTREE_EOF;
+ break;
+ }
+ info->curr_node = rb_first(&info->root);
+ }
+
+ fname = rb_entry(info->curr_node, struct fname, rb_hash);
+ info->curr_hash = fname->hash;
+ info->curr_minor_hash = fname->minor_hash;
+ if (call_filldir(filp, dirent, filldir, fname))
+ break;
+
+ info->curr_node = rb_next(info->curr_node);
+ if (!info->curr_node) {
+ if (info->next_hash == ~0) {
+ filp->f_pos = EXT4_HTREE_EOF;
+ break;
+ }
+ info->curr_hash = info->next_hash;
+ info->curr_minor_hash = 0;
+ }
+ }
+finished:
+ info->last_pos = filp->f_pos;
+ return 0;
+}
+
+static int ext4_release_dir (struct inode * inode, struct file * filp)
+{
+ if (filp->private_data)
+ ext4_htree_free_dir_info(filp->private_data);
+
+ return 0;
+}
+
+#endif
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
new file mode 100644
index 000000000000..2608dce18f3e
--- /dev/null
+++ b/fs/ext4/extents.c
@@ -0,0 +1,2152 @@
+/*
+ * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
+ * Written by Alex Tomas <alex@clusterfs.com>
+ *
+ * Architecture independence:
+ * Copyright (c) 2005, Bull S.A.
+ * Written by Pierre Peiffer <pierre.peiffer@bull.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public Licens
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
+ */
+
+/*
+ * Extents support for EXT4
+ *
+ * TODO:
+ * - ext4*_error() should be used in some situations
+ * - analyze all BUG()/BUG_ON(), use -EIO where appropriate
+ * - smart tree reduction
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/jbd.h>
+#include <linux/smp_lock.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/quotaops.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/ext4_fs_extents.h>
+#include <asm/uaccess.h>
+
+
+/*
+ * ext_pblock:
+ * combine low and high parts of physical block number into ext4_fsblk_t
+ */
+static inline ext4_fsblk_t ext_pblock(struct ext4_extent *ex)
+{
+ ext4_fsblk_t block;
+
+ block = le32_to_cpu(ex->ee_start);
+ block |= ((ext4_fsblk_t) le16_to_cpu(ex->ee_start_hi) << 31) << 1;
+ return block;
+}
+
+/*
+ * idx_pblock:
+ * combine low and high parts of a leaf physical block number into ext4_fsblk_t
+ */
+static inline ext4_fsblk_t idx_pblock(struct ext4_extent_idx *ix)
+{
+ ext4_fsblk_t block;
+
+ block = le32_to_cpu(ix->ei_leaf);
+ block |= ((ext4_fsblk_t) le16_to_cpu(ix->ei_leaf_hi) << 31) << 1;
+ return block;
+}
+
+/*
+ * ext4_ext_store_pblock:
+ * stores a large physical block number into an extent struct,
+ * breaking it into parts
+ */
+static inline void ext4_ext_store_pblock(struct ext4_extent *ex, ext4_fsblk_t pb)
+{
+ ex->ee_start = cpu_to_le32((unsigned long) (pb & 0xffffffff));
+ ex->ee_start_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
+}
+
+/*
+ * ext4_idx_store_pblock:
+ * stores a large physical block number into an index struct,
+ * breaking it into parts
+ */
+static inline void ext4_idx_store_pblock(struct ext4_extent_idx *ix, ext4_fsblk_t pb)
+{
+ ix->ei_leaf = cpu_to_le32((unsigned long) (pb & 0xffffffff));
+ ix->ei_leaf_hi = cpu_to_le16((unsigned long) ((pb >> 31) >> 1) & 0xffff);
+}
+
+static int ext4_ext_check_header(const char *function, struct inode *inode,
+ struct ext4_extent_header *eh)
+{
+ const char *error_msg = NULL;
+
+ if (unlikely(eh->eh_magic != EXT4_EXT_MAGIC)) {
+ error_msg = "invalid magic";
+ goto corrupted;
+ }
+ if (unlikely(eh->eh_max == 0)) {
+ error_msg = "invalid eh_max";
+ goto corrupted;
+ }
+ if (unlikely(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max))) {
+ error_msg = "invalid eh_entries";
+ goto corrupted;
+ }
+ return 0;
+
+corrupted:
+ ext4_error(inode->i_sb, function,
+ "bad header in inode #%lu: %s - magic %x, "
+ "entries %u, max %u, depth %u",
+ inode->i_ino, error_msg, le16_to_cpu(eh->eh_magic),
+ le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max),
+ le16_to_cpu(eh->eh_depth));
+
+ return -EIO;
+}
+
+static handle_t *ext4_ext_journal_restart(handle_t *handle, int needed)
+{
+ int err;
+
+ if (handle->h_buffer_credits > needed)
+ return handle;
+ if (!ext4_journal_extend(handle, needed))
+ return handle;
+ err = ext4_journal_restart(handle, needed);
+
+ return handle;
+}
+
+/*
+ * could return:
+ * - EROFS
+ * - ENOMEM
+ */
+static int ext4_ext_get_access(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ if (path->p_bh) {
+ /* path points to block */
+ return ext4_journal_get_write_access(handle, path->p_bh);
+ }
+ /* path points to leaf/index in inode body */
+ /* we use in-core data, no need to protect them */
+ return 0;
+}
+
+/*
+ * could return:
+ * - EROFS
+ * - ENOMEM
+ * - EIO
+ */
+static int ext4_ext_dirty(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ int err;
+ if (path->p_bh) {
+ /* path points to block */
+ err = ext4_journal_dirty_metadata(handle, path->p_bh);
+ } else {
+ /* path points to leaf/index in inode body */
+ err = ext4_mark_inode_dirty(handle, inode);
+ }
+ return err;
+}
+
+static ext4_fsblk_t ext4_ext_find_goal(struct inode *inode,
+ struct ext4_ext_path *path,
+ ext4_fsblk_t block)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ ext4_fsblk_t bg_start;
+ ext4_grpblk_t colour;
+ int depth;
+
+ if (path) {
+ struct ext4_extent *ex;
+ depth = path->p_depth;
+
+ /* try to predict block placement */
+ if ((ex = path[depth].p_ext))
+ return ext_pblock(ex)+(block-le32_to_cpu(ex->ee_block));
+
+ /* it looks like index is empty;
+ * try to find starting block from index itself */
+ if (path[depth].p_bh)
+ return path[depth].p_bh->b_blocknr;
+ }
+
+ /* OK. use inode's group */
+ bg_start = (ei->i_block_group * EXT4_BLOCKS_PER_GROUP(inode->i_sb)) +
+ le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_first_data_block);
+ colour = (current->pid % 16) *
+ (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
+ return bg_start + colour + block;
+}
+
+static ext4_fsblk_t
+ext4_ext_new_block(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *ex, int *err)
+{
+ ext4_fsblk_t goal, newblock;
+
+ goal = ext4_ext_find_goal(inode, path, le32_to_cpu(ex->ee_block));
+ newblock = ext4_new_block(handle, inode, goal, err);
+ return newblock;
+}
+
+static inline int ext4_ext_space_block(struct inode *inode)
+{
+ int size;
+
+ size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
+ / sizeof(struct ext4_extent);
+#ifdef AGRESSIVE_TEST
+ if (size > 6)
+ size = 6;
+#endif
+ return size;
+}
+
+static inline int ext4_ext_space_block_idx(struct inode *inode)
+{
+ int size;
+
+ size = (inode->i_sb->s_blocksize - sizeof(struct ext4_extent_header))
+ / sizeof(struct ext4_extent_idx);
+#ifdef AGRESSIVE_TEST
+ if (size > 5)
+ size = 5;
+#endif
+ return size;
+}
+
+static inline int ext4_ext_space_root(struct inode *inode)
+{
+ int size;
+
+ size = sizeof(EXT4_I(inode)->i_data);
+ size -= sizeof(struct ext4_extent_header);
+ size /= sizeof(struct ext4_extent);
+#ifdef AGRESSIVE_TEST
+ if (size > 3)
+ size = 3;
+#endif
+ return size;
+}
+
+static inline int ext4_ext_space_root_idx(struct inode *inode)
+{
+ int size;
+
+ size = sizeof(EXT4_I(inode)->i_data);
+ size -= sizeof(struct ext4_extent_header);
+ size /= sizeof(struct ext4_extent_idx);
+#ifdef AGRESSIVE_TEST
+ if (size > 4)
+ size = 4;
+#endif
+ return size;
+}
+
+#ifdef EXT_DEBUG
+static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
+{
+ int k, l = path->p_depth;
+
+ ext_debug("path:");
+ for (k = 0; k <= l; k++, path++) {
+ if (path->p_idx) {
+ ext_debug(" %d->%llu", le32_to_cpu(path->p_idx->ei_block),
+ idx_pblock(path->p_idx));
+ } else if (path->p_ext) {
+ ext_debug(" %d:%d:%llu ",
+ le32_to_cpu(path->p_ext->ee_block),
+ le16_to_cpu(path->p_ext->ee_len),
+ ext_pblock(path->p_ext));
+ } else
+ ext_debug(" []");
+ }
+ ext_debug("\n");
+}
+
+static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
+{
+ int depth = ext_depth(inode);
+ struct ext4_extent_header *eh;
+ struct ext4_extent *ex;
+ int i;
+
+ if (!path)
+ return;
+
+ eh = path[depth].p_hdr;
+ ex = EXT_FIRST_EXTENT(eh);
+
+ for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
+ ext_debug("%d:%d:%llu ", le32_to_cpu(ex->ee_block),
+ le16_to_cpu(ex->ee_len), ext_pblock(ex));
+ }
+ ext_debug("\n");
+}
+#else
+#define ext4_ext_show_path(inode,path)
+#define ext4_ext_show_leaf(inode,path)
+#endif
+
+static void ext4_ext_drop_refs(struct ext4_ext_path *path)
+{
+ int depth = path->p_depth;
+ int i;
+
+ for (i = 0; i <= depth; i++, path++)
+ if (path->p_bh) {
+ brelse(path->p_bh);
+ path->p_bh = NULL;
+ }
+}
+
+/*
+ * ext4_ext_binsearch_idx:
+ * binary search for the closest index of the given block
+ */
+static void
+ext4_ext_binsearch_idx(struct inode *inode, struct ext4_ext_path *path, int block)
+{
+ struct ext4_extent_header *eh = path->p_hdr;
+ struct ext4_extent_idx *r, *l, *m;
+
+ BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
+ BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
+ BUG_ON(le16_to_cpu(eh->eh_entries) <= 0);
+
+ ext_debug("binsearch for %d(idx): ", block);
+
+ l = EXT_FIRST_INDEX(eh) + 1;
+ r = EXT_FIRST_INDEX(eh) + le16_to_cpu(eh->eh_entries) - 1;
+ while (l <= r) {
+ m = l + (r - l) / 2;
+ if (block < le32_to_cpu(m->ei_block))
+ r = m - 1;
+ else
+ l = m + 1;
+ ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ei_block,
+ m, m->ei_block, r, r->ei_block);
+ }
+
+ path->p_idx = l - 1;
+ ext_debug(" -> %d->%lld ", le32_to_cpu(path->p_idx->ei_block),
+ idx_block(path->p_idx));
+
+#ifdef CHECK_BINSEARCH
+ {
+ struct ext4_extent_idx *chix, *ix;
+ int k;
+
+ chix = ix = EXT_FIRST_INDEX(eh);
+ for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ix++) {
+ if (k != 0 &&
+ le32_to_cpu(ix->ei_block) <= le32_to_cpu(ix[-1].ei_block)) {
+ printk("k=%d, ix=0x%p, first=0x%p\n", k,
+ ix, EXT_FIRST_INDEX(eh));
+ printk("%u <= %u\n",
+ le32_to_cpu(ix->ei_block),
+ le32_to_cpu(ix[-1].ei_block));
+ }
+ BUG_ON(k && le32_to_cpu(ix->ei_block)
+ <= le32_to_cpu(ix[-1].ei_block));
+ if (block < le32_to_cpu(ix->ei_block))
+ break;
+ chix = ix;
+ }
+ BUG_ON(chix != path->p_idx);
+ }
+#endif
+
+}
+
+/*
+ * ext4_ext_binsearch:
+ * binary search for closest extent of the given block
+ */
+static void
+ext4_ext_binsearch(struct inode *inode, struct ext4_ext_path *path, int block)
+{
+ struct ext4_extent_header *eh = path->p_hdr;
+ struct ext4_extent *r, *l, *m;
+
+ BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
+ BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
+
+ if (eh->eh_entries == 0) {
+ /*
+ * this leaf is empty:
+ * we get such a leaf in split/add case
+ */
+ return;
+ }
+
+ ext_debug("binsearch for %d: ", block);
+
+ l = EXT_FIRST_EXTENT(eh) + 1;
+ r = EXT_FIRST_EXTENT(eh) + le16_to_cpu(eh->eh_entries) - 1;
+
+ while (l <= r) {
+ m = l + (r - l) / 2;
+ if (block < le32_to_cpu(m->ee_block))
+ r = m - 1;
+ else
+ l = m + 1;
+ ext_debug("%p(%u):%p(%u):%p(%u) ", l, l->ee_block,
+ m, m->ee_block, r, r->ee_block);
+ }
+
+ path->p_ext = l - 1;
+ ext_debug(" -> %d:%llu:%d ",
+ le32_to_cpu(path->p_ext->ee_block),
+ ext_pblock(path->p_ext),
+ le16_to_cpu(path->p_ext->ee_len));
+
+#ifdef CHECK_BINSEARCH
+ {
+ struct ext4_extent *chex, *ex;
+ int k;
+
+ chex = ex = EXT_FIRST_EXTENT(eh);
+ for (k = 0; k < le16_to_cpu(eh->eh_entries); k++, ex++) {
+ BUG_ON(k && le32_to_cpu(ex->ee_block)
+ <= le32_to_cpu(ex[-1].ee_block));
+ if (block < le32_to_cpu(ex->ee_block))
+ break;
+ chex = ex;
+ }
+ BUG_ON(chex != path->p_ext);
+ }
+#endif
+
+}
+
+int ext4_ext_tree_init(handle_t *handle, struct inode *inode)
+{
+ struct ext4_extent_header *eh;
+
+ eh = ext_inode_hdr(inode);
+ eh->eh_depth = 0;
+ eh->eh_entries = 0;
+ eh->eh_magic = EXT4_EXT_MAGIC;
+ eh->eh_max = cpu_to_le16(ext4_ext_space_root(inode));
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_ext_invalidate_cache(inode);
+ return 0;
+}
+
+struct ext4_ext_path *
+ext4_ext_find_extent(struct inode *inode, int block, struct ext4_ext_path *path)
+{
+ struct ext4_extent_header *eh;
+ struct buffer_head *bh;
+ short int depth, i, ppos = 0, alloc = 0;
+
+ eh = ext_inode_hdr(inode);
+ BUG_ON(eh == NULL);
+ if (ext4_ext_check_header(__FUNCTION__, inode, eh))
+ return ERR_PTR(-EIO);
+
+ i = depth = ext_depth(inode);
+
+ /* account possible depth increase */
+ if (!path) {
+ path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 2),
+ GFP_NOFS);
+ if (!path)
+ return ERR_PTR(-ENOMEM);
+ alloc = 1;
+ }
+ memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
+ path[0].p_hdr = eh;
+
+ /* walk through the tree */
+ while (i) {
+ ext_debug("depth %d: num %d, max %d\n",
+ ppos, le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
+ ext4_ext_binsearch_idx(inode, path + ppos, block);
+ path[ppos].p_block = idx_pblock(path[ppos].p_idx);
+ path[ppos].p_depth = i;
+ path[ppos].p_ext = NULL;
+
+ bh = sb_bread(inode->i_sb, path[ppos].p_block);
+ if (!bh)
+ goto err;
+
+ eh = ext_block_hdr(bh);
+ ppos++;
+ BUG_ON(ppos > depth);
+ path[ppos].p_bh = bh;
+ path[ppos].p_hdr = eh;
+ i--;
+
+ if (ext4_ext_check_header(__FUNCTION__, inode, eh))
+ goto err;
+ }
+
+ path[ppos].p_depth = i;
+ path[ppos].p_hdr = eh;
+ path[ppos].p_ext = NULL;
+ path[ppos].p_idx = NULL;
+
+ if (ext4_ext_check_header(__FUNCTION__, inode, eh))
+ goto err;
+
+ /* find extent */
+ ext4_ext_binsearch(inode, path + ppos, block);
+
+ ext4_ext_show_path(inode, path);
+
+ return path;
+
+err:
+ ext4_ext_drop_refs(path);
+ if (alloc)
+ kfree(path);
+ return ERR_PTR(-EIO);
+}
+
+/*
+ * ext4_ext_insert_index:
+ * insert new index [@logical;@ptr] into the block at @curp;
+ * check where to insert: before @curp or after @curp
+ */
+static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *curp,
+ int logical, ext4_fsblk_t ptr)
+{
+ struct ext4_extent_idx *ix;
+ int len, err;
+
+ if ((err = ext4_ext_get_access(handle, inode, curp)))
+ return err;
+
+ BUG_ON(logical == le32_to_cpu(curp->p_idx->ei_block));
+ len = EXT_MAX_INDEX(curp->p_hdr) - curp->p_idx;
+ if (logical > le32_to_cpu(curp->p_idx->ei_block)) {
+ /* insert after */
+ if (curp->p_idx != EXT_LAST_INDEX(curp->p_hdr)) {
+ len = (len - 1) * sizeof(struct ext4_extent_idx);
+ len = len < 0 ? 0 : len;
+ ext_debug("insert new index %d after: %d. "
+ "move %d from 0x%p to 0x%p\n",
+ logical, ptr, len,
+ (curp->p_idx + 1), (curp->p_idx + 2));
+ memmove(curp->p_idx + 2, curp->p_idx + 1, len);
+ }
+ ix = curp->p_idx + 1;
+ } else {
+ /* insert before */
+ len = len * sizeof(struct ext4_extent_idx);
+ len = len < 0 ? 0 : len;
+ ext_debug("insert new index %d before: %d. "
+ "move %d from 0x%p to 0x%p\n",
+ logical, ptr, len,
+ curp->p_idx, (curp->p_idx + 1));
+ memmove(curp->p_idx + 1, curp->p_idx, len);
+ ix = curp->p_idx;
+ }
+
+ ix->ei_block = cpu_to_le32(logical);
+ ext4_idx_store_pblock(ix, ptr);
+ curp->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(curp->p_hdr->eh_entries)+1);
+
+ BUG_ON(le16_to_cpu(curp->p_hdr->eh_entries)
+ > le16_to_cpu(curp->p_hdr->eh_max));
+ BUG_ON(ix > EXT_LAST_INDEX(curp->p_hdr));
+
+ err = ext4_ext_dirty(handle, inode, curp);
+ ext4_std_error(inode->i_sb, err);
+
+ return err;
+}
+
+/*
+ * ext4_ext_split:
+ * inserts new subtree into the path, using free index entry
+ * at depth @at:
+ * - allocates all needed blocks (new leaf and all intermediate index blocks)
+ * - makes decision where to split
+ * - moves remaining extents and index entries (right to the split point)
+ * into the newly allocated blocks
+ * - initializes subtree
+ */
+static int ext4_ext_split(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext, int at)
+{
+ struct buffer_head *bh = NULL;
+ int depth = ext_depth(inode);
+ struct ext4_extent_header *neh;
+ struct ext4_extent_idx *fidx;
+ struct ext4_extent *ex;
+ int i = at, k, m, a;
+ ext4_fsblk_t newblock, oldblock;
+ __le32 border;
+ ext4_fsblk_t *ablocks = NULL; /* array of allocated blocks */
+ int err = 0;
+
+ /* make decision: where to split? */
+ /* FIXME: now decision is simplest: at current extent */
+
+ /* if current leaf will be split, then we should use
+ * border from split point */
+ BUG_ON(path[depth].p_ext > EXT_MAX_EXTENT(path[depth].p_hdr));
+ if (path[depth].p_ext != EXT_MAX_EXTENT(path[depth].p_hdr)) {
+ border = path[depth].p_ext[1].ee_block;
+ ext_debug("leaf will be split."
+ " next leaf starts at %d\n",
+ le32_to_cpu(border));
+ } else {
+ border = newext->ee_block;
+ ext_debug("leaf will be added."
+ " next leaf starts at %d\n",
+ le32_to_cpu(border));
+ }
+
+ /*
+ * If error occurs, then we break processing
+ * and mark filesystem read-only. index won't
+ * be inserted and tree will be in consistent
+ * state. Next mount will repair buffers too.
+ */
+
+ /*
+ * Get array to track all allocated blocks.
+ * We need this to handle errors and free blocks
+ * upon them.
+ */
+ ablocks = kmalloc(sizeof(ext4_fsblk_t) * depth, GFP_NOFS);
+ if (!ablocks)
+ return -ENOMEM;
+ memset(ablocks, 0, sizeof(ext4_fsblk_t) * depth);
+
+ /* allocate all needed blocks */
+ ext_debug("allocate %d blocks for indexes/leaf\n", depth - at);
+ for (a = 0; a < depth - at; a++) {
+ newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+ if (newblock == 0)
+ goto cleanup;
+ ablocks[a] = newblock;
+ }
+
+ /* initialize new leaf */
+ newblock = ablocks[--a];
+ BUG_ON(newblock == 0);
+ bh = sb_getblk(inode->i_sb, newblock);
+ if (!bh) {
+ err = -EIO;
+ goto cleanup;
+ }
+ lock_buffer(bh);
+
+ if ((err = ext4_journal_get_create_access(handle, bh)))
+ goto cleanup;
+
+ neh = ext_block_hdr(bh);
+ neh->eh_entries = 0;
+ neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
+ neh->eh_magic = EXT4_EXT_MAGIC;
+ neh->eh_depth = 0;
+ ex = EXT_FIRST_EXTENT(neh);
+
+ /* move remainder of path[depth] to the new leaf */
+ BUG_ON(path[depth].p_hdr->eh_entries != path[depth].p_hdr->eh_max);
+ /* start copy from next extent */
+ /* TODO: we could do it by single memmove */
+ m = 0;
+ path[depth].p_ext++;
+ while (path[depth].p_ext <=
+ EXT_MAX_EXTENT(path[depth].p_hdr)) {
+ ext_debug("move %d:%llu:%d in new leaf %llu\n",
+ le32_to_cpu(path[depth].p_ext->ee_block),
+ ext_pblock(path[depth].p_ext),
+ le16_to_cpu(path[depth].p_ext->ee_len),
+ newblock);
+ /*memmove(ex++, path[depth].p_ext++,
+ sizeof(struct ext4_extent));
+ neh->eh_entries++;*/
+ path[depth].p_ext++;
+ m++;
+ }
+ if (m) {
+ memmove(ex, path[depth].p_ext-m, sizeof(struct ext4_extent)*m);
+ neh->eh_entries = cpu_to_le16(le16_to_cpu(neh->eh_entries)+m);
+ }
+
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+
+ if ((err = ext4_journal_dirty_metadata(handle, bh)))
+ goto cleanup;
+ brelse(bh);
+ bh = NULL;
+
+ /* correct old leaf */
+ if (m) {
+ if ((err = ext4_ext_get_access(handle, inode, path + depth)))
+ goto cleanup;
+ path[depth].p_hdr->eh_entries =
+ cpu_to_le16(le16_to_cpu(path[depth].p_hdr->eh_entries)-m);
+ if ((err = ext4_ext_dirty(handle, inode, path + depth)))
+ goto cleanup;
+
+ }
+
+ /* create intermediate indexes */
+ k = depth - at - 1;
+ BUG_ON(k < 0);
+ if (k)
+ ext_debug("create %d intermediate indices\n", k);
+ /* insert new index into current index block */
+ /* current depth stored in i var */
+ i = depth - 1;
+ while (k--) {
+ oldblock = newblock;
+ newblock = ablocks[--a];
+ bh = sb_getblk(inode->i_sb, (ext4_fsblk_t)newblock);
+ if (!bh) {
+ err = -EIO;
+ goto cleanup;
+ }
+ lock_buffer(bh);
+
+ if ((err = ext4_journal_get_create_access(handle, bh)))
+ goto cleanup;
+
+ neh = ext_block_hdr(bh);
+ neh->eh_entries = cpu_to_le16(1);
+ neh->eh_magic = EXT4_EXT_MAGIC;
+ neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
+ neh->eh_depth = cpu_to_le16(depth - i);
+ fidx = EXT_FIRST_INDEX(neh);
+ fidx->ei_block = border;
+ ext4_idx_store_pblock(fidx, oldblock);
+
+ ext_debug("int.index at %d (block %llu): %lu -> %llu\n", i,
+ newblock, (unsigned long) le32_to_cpu(border),
+ oldblock);
+ /* copy indexes */
+ m = 0;
+ path[i].p_idx++;
+
+ ext_debug("cur 0x%p, last 0x%p\n", path[i].p_idx,
+ EXT_MAX_INDEX(path[i].p_hdr));
+ BUG_ON(EXT_MAX_INDEX(path[i].p_hdr) !=
+ EXT_LAST_INDEX(path[i].p_hdr));
+ while (path[i].p_idx <= EXT_MAX_INDEX(path[i].p_hdr)) {
+ ext_debug("%d: move %d:%d in new index %llu\n", i,
+ le32_to_cpu(path[i].p_idx->ei_block),
+ idx_pblock(path[i].p_idx),
+ newblock);
+ /*memmove(++fidx, path[i].p_idx++,
+ sizeof(struct ext4_extent_idx));
+ neh->eh_entries++;
+ BUG_ON(neh->eh_entries > neh->eh_max);*/
+ path[i].p_idx++;
+ m++;
+ }
+ if (m) {
+ memmove(++fidx, path[i].p_idx - m,
+ sizeof(struct ext4_extent_idx) * m);
+ neh->eh_entries =
+ cpu_to_le16(le16_to_cpu(neh->eh_entries) + m);
+ }
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+
+ if ((err = ext4_journal_dirty_metadata(handle, bh)))
+ goto cleanup;
+ brelse(bh);
+ bh = NULL;
+
+ /* correct old index */
+ if (m) {
+ err = ext4_ext_get_access(handle, inode, path + i);
+ if (err)
+ goto cleanup;
+ path[i].p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path[i].p_hdr->eh_entries)-m);
+ err = ext4_ext_dirty(handle, inode, path + i);
+ if (err)
+ goto cleanup;
+ }
+
+ i--;
+ }
+
+ /* insert new index */
+ if (err)
+ goto cleanup;
+
+ err = ext4_ext_insert_index(handle, inode, path + at,
+ le32_to_cpu(border), newblock);
+
+cleanup:
+ if (bh) {
+ if (buffer_locked(bh))
+ unlock_buffer(bh);
+ brelse(bh);
+ }
+
+ if (err) {
+ /* free all allocated blocks in error case */
+ for (i = 0; i < depth; i++) {
+ if (!ablocks[i])
+ continue;
+ ext4_free_blocks(handle, inode, ablocks[i], 1);
+ }
+ }
+ kfree(ablocks);
+
+ return err;
+}
+
+/*
+ * ext4_ext_grow_indepth:
+ * implements tree growing procedure:
+ * - allocates new block
+ * - moves top-level data (index block or leaf) into the new block
+ * - initializes new top-level, creating index that points to the
+ * just created block
+ */
+static int ext4_ext_grow_indepth(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext)
+{
+ struct ext4_ext_path *curp = path;
+ struct ext4_extent_header *neh;
+ struct ext4_extent_idx *fidx;
+ struct buffer_head *bh;
+ ext4_fsblk_t newblock;
+ int err = 0;
+
+ newblock = ext4_ext_new_block(handle, inode, path, newext, &err);
+ if (newblock == 0)
+ return err;
+
+ bh = sb_getblk(inode->i_sb, newblock);
+ if (!bh) {
+ err = -EIO;
+ ext4_std_error(inode->i_sb, err);
+ return err;
+ }
+ lock_buffer(bh);
+
+ if ((err = ext4_journal_get_create_access(handle, bh))) {
+ unlock_buffer(bh);
+ goto out;
+ }
+
+ /* move top-level index/leaf into new block */
+ memmove(bh->b_data, curp->p_hdr, sizeof(EXT4_I(inode)->i_data));
+
+ /* set size of new block */
+ neh = ext_block_hdr(bh);
+ /* old root could have indexes or leaves
+ * so calculate e_max right way */
+ if (ext_depth(inode))
+ neh->eh_max = cpu_to_le16(ext4_ext_space_block_idx(inode));
+ else
+ neh->eh_max = cpu_to_le16(ext4_ext_space_block(inode));
+ neh->eh_magic = EXT4_EXT_MAGIC;
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+
+ if ((err = ext4_journal_dirty_metadata(handle, bh)))
+ goto out;
+
+ /* create index in new top-level index: num,max,pointer */
+ if ((err = ext4_ext_get_access(handle, inode, curp)))
+ goto out;
+
+ curp->p_hdr->eh_magic = EXT4_EXT_MAGIC;
+ curp->p_hdr->eh_max = cpu_to_le16(ext4_ext_space_root_idx(inode));
+ curp->p_hdr->eh_entries = cpu_to_le16(1);
+ curp->p_idx = EXT_FIRST_INDEX(curp->p_hdr);
+ /* FIXME: it works, but actually path[0] can be index */
+ curp->p_idx->ei_block = EXT_FIRST_EXTENT(path[0].p_hdr)->ee_block;
+ ext4_idx_store_pblock(curp->p_idx, newblock);
+
+ neh = ext_inode_hdr(inode);
+ fidx = EXT_FIRST_INDEX(neh);
+ ext_debug("new root: num %d(%d), lblock %d, ptr %llu\n",
+ le16_to_cpu(neh->eh_entries), le16_to_cpu(neh->eh_max),
+ le32_to_cpu(fidx->ei_block), idx_pblock(fidx));
+
+ neh->eh_depth = cpu_to_le16(path->p_depth + 1);
+ err = ext4_ext_dirty(handle, inode, curp);
+out:
+ brelse(bh);
+
+ return err;
+}
+
+/*
+ * ext4_ext_create_new_leaf:
+ * finds empty index and adds new leaf.
+ * if no free index is found, then it requests in-depth growing.
+ */
+static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext)
+{
+ struct ext4_ext_path *curp;
+ int depth, i, err = 0;
+
+repeat:
+ i = depth = ext_depth(inode);
+
+ /* walk up to the tree and look for free index entry */
+ curp = path + depth;
+ while (i > 0 && !EXT_HAS_FREE_INDEX(curp)) {
+ i--;
+ curp--;
+ }
+
+ /* we use already allocated block for index block,
+ * so subsequent data blocks should be contiguous */
+ if (EXT_HAS_FREE_INDEX(curp)) {
+ /* if we found index with free entry, then use that
+ * entry: create all needed subtree and add new leaf */
+ err = ext4_ext_split(handle, inode, path, newext, i);
+
+ /* refill path */
+ ext4_ext_drop_refs(path);
+ path = ext4_ext_find_extent(inode,
+ le32_to_cpu(newext->ee_block),
+ path);
+ if (IS_ERR(path))
+ err = PTR_ERR(path);
+ } else {
+ /* tree is full, time to grow in depth */
+ err = ext4_ext_grow_indepth(handle, inode, path, newext);
+ if (err)
+ goto out;
+
+ /* refill path */
+ ext4_ext_drop_refs(path);
+ path = ext4_ext_find_extent(inode,
+ le32_to_cpu(newext->ee_block),
+ path);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ goto out;
+ }
+
+ /*
+ * only first (depth 0 -> 1) produces free space;
+ * in all other cases we have to split the grown tree
+ */
+ depth = ext_depth(inode);
+ if (path[depth].p_hdr->eh_entries == path[depth].p_hdr->eh_max) {
+ /* now we need to split */
+ goto repeat;
+ }
+ }
+
+out:
+ return err;
+}
+
+/*
+ * ext4_ext_next_allocated_block:
+ * returns allocated block in subsequent extent or EXT_MAX_BLOCK.
+ * NOTE: it considers block number from index entry as
+ * allocated block. Thus, index entries have to be consistent
+ * with leaves.
+ */
+static unsigned long
+ext4_ext_next_allocated_block(struct ext4_ext_path *path)
+{
+ int depth;
+
+ BUG_ON(path == NULL);
+ depth = path->p_depth;
+
+ if (depth == 0 && path->p_ext == NULL)
+ return EXT_MAX_BLOCK;
+
+ while (depth >= 0) {
+ if (depth == path->p_depth) {
+ /* leaf */
+ if (path[depth].p_ext !=
+ EXT_LAST_EXTENT(path[depth].p_hdr))
+ return le32_to_cpu(path[depth].p_ext[1].ee_block);
+ } else {
+ /* index */
+ if (path[depth].p_idx !=
+ EXT_LAST_INDEX(path[depth].p_hdr))
+ return le32_to_cpu(path[depth].p_idx[1].ei_block);
+ }
+ depth--;
+ }
+
+ return EXT_MAX_BLOCK;
+}
+
+/*
+ * ext4_ext_next_leaf_block:
+ * returns first allocated block from next leaf or EXT_MAX_BLOCK
+ */
+static unsigned ext4_ext_next_leaf_block(struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ int depth;
+
+ BUG_ON(path == NULL);
+ depth = path->p_depth;
+
+ /* zero-tree has no leaf blocks at all */
+ if (depth == 0)
+ return EXT_MAX_BLOCK;
+
+ /* go to index block */
+ depth--;
+
+ while (depth >= 0) {
+ if (path[depth].p_idx !=
+ EXT_LAST_INDEX(path[depth].p_hdr))
+ return le32_to_cpu(path[depth].p_idx[1].ei_block);
+ depth--;
+ }
+
+ return EXT_MAX_BLOCK;
+}
+
+/*
+ * ext4_ext_correct_indexes:
+ * if leaf gets modified and modified extent is first in the leaf,
+ * then we have to correct all indexes above.
+ * TODO: do we need to correct tree in all cases?
+ */
+int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ struct ext4_extent_header *eh;
+ int depth = ext_depth(inode);
+ struct ext4_extent *ex;
+ __le32 border;
+ int k, err = 0;
+
+ eh = path[depth].p_hdr;
+ ex = path[depth].p_ext;
+ BUG_ON(ex == NULL);
+ BUG_ON(eh == NULL);
+
+ if (depth == 0) {
+ /* there is no tree at all */
+ return 0;
+ }
+
+ if (ex != EXT_FIRST_EXTENT(eh)) {
+ /* we correct tree if first leaf got modified only */
+ return 0;
+ }
+
+ /*
+ * TODO: we need correction if border is smaller than current one
+ */
+ k = depth - 1;
+ border = path[depth].p_ext->ee_block;
+ if ((err = ext4_ext_get_access(handle, inode, path + k)))
+ return err;
+ path[k].p_idx->ei_block = border;
+ if ((err = ext4_ext_dirty(handle, inode, path + k)))
+ return err;
+
+ while (k--) {
+ /* change all left-side indexes */
+ if (path[k+1].p_idx != EXT_FIRST_INDEX(path[k+1].p_hdr))
+ break;
+ if ((err = ext4_ext_get_access(handle, inode, path + k)))
+ break;
+ path[k].p_idx->ei_block = border;
+ if ((err = ext4_ext_dirty(handle, inode, path + k)))
+ break;
+ }
+
+ return err;
+}
+
+static int inline
+ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
+ struct ext4_extent *ex2)
+{
+ if (le32_to_cpu(ex1->ee_block) + le16_to_cpu(ex1->ee_len) !=
+ le32_to_cpu(ex2->ee_block))
+ return 0;
+
+ /*
+ * To allow future support for preallocated extents to be added
+ * as an RO_COMPAT feature, refuse to merge to extents if
+ * this can result in the top bit of ee_len being set.
+ */
+ if (le16_to_cpu(ex1->ee_len) + le16_to_cpu(ex2->ee_len) > EXT_MAX_LEN)
+ return 0;
+#ifdef AGRESSIVE_TEST
+ if (le16_to_cpu(ex1->ee_len) >= 4)
+ return 0;
+#endif
+
+ if (ext_pblock(ex1) + le16_to_cpu(ex1->ee_len) == ext_pblock(ex2))
+ return 1;
+ return 0;
+}
+
+/*
+ * ext4_ext_insert_extent:
+ * tries to merge requsted extent into the existing extent or
+ * inserts requested extent as new one into the tree,
+ * creating new leaf in the no-space case.
+ */
+int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path,
+ struct ext4_extent *newext)
+{
+ struct ext4_extent_header * eh;
+ struct ext4_extent *ex, *fex;
+ struct ext4_extent *nearex; /* nearest extent */
+ struct ext4_ext_path *npath = NULL;
+ int depth, len, err, next;
+
+ BUG_ON(newext->ee_len == 0);
+ depth = ext_depth(inode);
+ ex = path[depth].p_ext;
+ BUG_ON(path[depth].p_hdr == NULL);
+
+ /* try to insert block into found extent and return */
+ if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
+ ext_debug("append %d block to %d:%d (from %llu)\n",
+ le16_to_cpu(newext->ee_len),
+ le32_to_cpu(ex->ee_block),
+ le16_to_cpu(ex->ee_len), ext_pblock(ex));
+ if ((err = ext4_ext_get_access(handle, inode, path + depth)))
+ return err;
+ ex->ee_len = cpu_to_le16(le16_to_cpu(ex->ee_len)
+ + le16_to_cpu(newext->ee_len));
+ eh = path[depth].p_hdr;
+ nearex = ex;
+ goto merge;
+ }
+
+repeat:
+ depth = ext_depth(inode);
+ eh = path[depth].p_hdr;
+ if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max))
+ goto has_space;
+
+ /* probably next leaf has space for us? */
+ fex = EXT_LAST_EXTENT(eh);
+ next = ext4_ext_next_leaf_block(inode, path);
+ if (le32_to_cpu(newext->ee_block) > le32_to_cpu(fex->ee_block)
+ && next != EXT_MAX_BLOCK) {
+ ext_debug("next leaf block - %d\n", next);
+ BUG_ON(npath != NULL);
+ npath = ext4_ext_find_extent(inode, next, NULL);
+ if (IS_ERR(npath))
+ return PTR_ERR(npath);
+ BUG_ON(npath->p_depth != path->p_depth);
+ eh = npath[depth].p_hdr;
+ if (le16_to_cpu(eh->eh_entries) < le16_to_cpu(eh->eh_max)) {
+ ext_debug("next leaf isnt full(%d)\n",
+ le16_to_cpu(eh->eh_entries));
+ path = npath;
+ goto repeat;
+ }
+ ext_debug("next leaf has no free space(%d,%d)\n",
+ le16_to_cpu(eh->eh_entries), le16_to_cpu(eh->eh_max));
+ }
+
+ /*
+ * There is no free space in the found leaf.
+ * We're gonna add a new leaf in the tree.
+ */
+ err = ext4_ext_create_new_leaf(handle, inode, path, newext);
+ if (err)
+ goto cleanup;
+ depth = ext_depth(inode);
+ eh = path[depth].p_hdr;
+
+has_space:
+ nearex = path[depth].p_ext;
+
+ if ((err = ext4_ext_get_access(handle, inode, path + depth)))
+ goto cleanup;
+
+ if (!nearex) {
+ /* there is no extent in this leaf, create first one */
+ ext_debug("first extent in the leaf: %d:%llu:%d\n",
+ le32_to_cpu(newext->ee_block),
+ ext_pblock(newext),
+ le16_to_cpu(newext->ee_len));
+ path[depth].p_ext = EXT_FIRST_EXTENT(eh);
+ } else if (le32_to_cpu(newext->ee_block)
+ > le32_to_cpu(nearex->ee_block)) {
+/* BUG_ON(newext->ee_block == nearex->ee_block); */
+ if (nearex != EXT_LAST_EXTENT(eh)) {
+ len = EXT_MAX_EXTENT(eh) - nearex;
+ len = (len - 1) * sizeof(struct ext4_extent);
+ len = len < 0 ? 0 : len;
+ ext_debug("insert %d:%llu:%d after: nearest 0x%p, "
+ "move %d from 0x%p to 0x%p\n",
+ le32_to_cpu(newext->ee_block),
+ ext_pblock(newext),
+ le16_to_cpu(newext->ee_len),
+ nearex, len, nearex + 1, nearex + 2);
+ memmove(nearex + 2, nearex + 1, len);
+ }
+ path[depth].p_ext = nearex + 1;
+ } else {
+ BUG_ON(newext->ee_block == nearex->ee_block);
+ len = (EXT_MAX_EXTENT(eh) - nearex) * sizeof(struct ext4_extent);
+ len = len < 0 ? 0 : len;
+ ext_debug("insert %d:%llu:%d before: nearest 0x%p, "
+ "move %d from 0x%p to 0x%p\n",
+ le32_to_cpu(newext->ee_block),
+ ext_pblock(newext),
+ le16_to_cpu(newext->ee_len),
+ nearex, len, nearex + 1, nearex + 2);
+ memmove(nearex + 1, nearex, len);
+ path[depth].p_ext = nearex;
+ }
+
+ eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)+1);
+ nearex = path[depth].p_ext;
+ nearex->ee_block = newext->ee_block;
+ nearex->ee_start = newext->ee_start;
+ nearex->ee_start_hi = newext->ee_start_hi;
+ nearex->ee_len = newext->ee_len;
+
+merge:
+ /* try to merge extents to the right */
+ while (nearex < EXT_LAST_EXTENT(eh)) {
+ if (!ext4_can_extents_be_merged(inode, nearex, nearex + 1))
+ break;
+ /* merge with next extent! */
+ nearex->ee_len = cpu_to_le16(le16_to_cpu(nearex->ee_len)
+ + le16_to_cpu(nearex[1].ee_len));
+ if (nearex + 1 < EXT_LAST_EXTENT(eh)) {
+ len = (EXT_LAST_EXTENT(eh) - nearex - 1)
+ * sizeof(struct ext4_extent);
+ memmove(nearex + 1, nearex + 2, len);
+ }
+ eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
+ BUG_ON(eh->eh_entries == 0);
+ }
+
+ /* try to merge extents to the left */
+
+ /* time to correct all indexes above */
+ err = ext4_ext_correct_indexes(handle, inode, path);
+ if (err)
+ goto cleanup;
+
+ err = ext4_ext_dirty(handle, inode, path + depth);
+
+cleanup:
+ if (npath) {
+ ext4_ext_drop_refs(npath);
+ kfree(npath);
+ }
+ ext4_ext_tree_changed(inode);
+ ext4_ext_invalidate_cache(inode);
+ return err;
+}
+
+int ext4_ext_walk_space(struct inode *inode, unsigned long block,
+ unsigned long num, ext_prepare_callback func,
+ void *cbdata)
+{
+ struct ext4_ext_path *path = NULL;
+ struct ext4_ext_cache cbex;
+ struct ext4_extent *ex;
+ unsigned long next, start = 0, end = 0;
+ unsigned long last = block + num;
+ int depth, exists, err = 0;
+
+ BUG_ON(func == NULL);
+ BUG_ON(inode == NULL);
+
+ while (block < last && block != EXT_MAX_BLOCK) {
+ num = last - block;
+ /* find extent for this block */
+ path = ext4_ext_find_extent(inode, block, path);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ path = NULL;
+ break;
+ }
+
+ depth = ext_depth(inode);
+ BUG_ON(path[depth].p_hdr == NULL);
+ ex = path[depth].p_ext;
+ next = ext4_ext_next_allocated_block(path);
+
+ exists = 0;
+ if (!ex) {
+ /* there is no extent yet, so try to allocate
+ * all requested space */
+ start = block;
+ end = block + num;
+ } else if (le32_to_cpu(ex->ee_block) > block) {
+ /* need to allocate space before found extent */
+ start = block;
+ end = le32_to_cpu(ex->ee_block);
+ if (block + num < end)
+ end = block + num;
+ } else if (block >=
+ le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len)) {
+ /* need to allocate space after found extent */
+ start = block;
+ end = block + num;
+ if (end >= next)
+ end = next;
+ } else if (block >= le32_to_cpu(ex->ee_block)) {
+ /*
+ * some part of requested space is covered
+ * by found extent
+ */
+ start = block;
+ end = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len);
+ if (block + num < end)
+ end = block + num;
+ exists = 1;
+ } else {
+ BUG();
+ }
+ BUG_ON(end <= start);
+
+ if (!exists) {
+ cbex.ec_block = start;
+ cbex.ec_len = end - start;
+ cbex.ec_start = 0;
+ cbex.ec_type = EXT4_EXT_CACHE_GAP;
+ } else {
+ cbex.ec_block = le32_to_cpu(ex->ee_block);
+ cbex.ec_len = le16_to_cpu(ex->ee_len);
+ cbex.ec_start = ext_pblock(ex);
+ cbex.ec_type = EXT4_EXT_CACHE_EXTENT;
+ }
+
+ BUG_ON(cbex.ec_len == 0);
+ err = func(inode, path, &cbex, cbdata);
+ ext4_ext_drop_refs(path);
+
+ if (err < 0)
+ break;
+ if (err == EXT_REPEAT)
+ continue;
+ else if (err == EXT_BREAK) {
+ err = 0;
+ break;
+ }
+
+ if (ext_depth(inode) != depth) {
+ /* depth was changed. we have to realloc path */
+ kfree(path);
+ path = NULL;
+ }
+
+ block = cbex.ec_block + cbex.ec_len;
+ }
+
+ if (path) {
+ ext4_ext_drop_refs(path);
+ kfree(path);
+ }
+
+ return err;
+}
+
+static inline void
+ext4_ext_put_in_cache(struct inode *inode, __u32 block,
+ __u32 len, __u32 start, int type)
+{
+ struct ext4_ext_cache *cex;
+ BUG_ON(len == 0);
+ cex = &EXT4_I(inode)->i_cached_extent;
+ cex->ec_type = type;
+ cex->ec_block = block;
+ cex->ec_len = len;
+ cex->ec_start = start;
+}
+
+/*
+ * ext4_ext_put_gap_in_cache:
+ * calculate boundaries of the gap that the requested block fits into
+ * and cache this gap
+ */
+static inline void
+ext4_ext_put_gap_in_cache(struct inode *inode, struct ext4_ext_path *path,
+ unsigned long block)
+{
+ int depth = ext_depth(inode);
+ unsigned long lblock, len;
+ struct ext4_extent *ex;
+
+ ex = path[depth].p_ext;
+ if (ex == NULL) {
+ /* there is no extent yet, so gap is [0;-] */
+ lblock = 0;
+ len = EXT_MAX_BLOCK;
+ ext_debug("cache gap(whole file):");
+ } else if (block < le32_to_cpu(ex->ee_block)) {
+ lblock = block;
+ len = le32_to_cpu(ex->ee_block) - block;
+ ext_debug("cache gap(before): %lu [%lu:%lu]",
+ (unsigned long) block,
+ (unsigned long) le32_to_cpu(ex->ee_block),
+ (unsigned long) le16_to_cpu(ex->ee_len));
+ } else if (block >= le32_to_cpu(ex->ee_block)
+ + le16_to_cpu(ex->ee_len)) {
+ lblock = le32_to_cpu(ex->ee_block)
+ + le16_to_cpu(ex->ee_len);
+ len = ext4_ext_next_allocated_block(path);
+ ext_debug("cache gap(after): [%lu:%lu] %lu",
+ (unsigned long) le32_to_cpu(ex->ee_block),
+ (unsigned long) le16_to_cpu(ex->ee_len),
+ (unsigned long) block);
+ BUG_ON(len == lblock);
+ len = len - lblock;
+ } else {
+ lblock = len = 0;
+ BUG();
+ }
+
+ ext_debug(" -> %lu:%lu\n", (unsigned long) lblock, len);
+ ext4_ext_put_in_cache(inode, lblock, len, 0, EXT4_EXT_CACHE_GAP);
+}
+
+static inline int
+ext4_ext_in_cache(struct inode *inode, unsigned long block,
+ struct ext4_extent *ex)
+{
+ struct ext4_ext_cache *cex;
+
+ cex = &EXT4_I(inode)->i_cached_extent;
+
+ /* has cache valid data? */
+ if (cex->ec_type == EXT4_EXT_CACHE_NO)
+ return EXT4_EXT_CACHE_NO;
+
+ BUG_ON(cex->ec_type != EXT4_EXT_CACHE_GAP &&
+ cex->ec_type != EXT4_EXT_CACHE_EXTENT);
+ if (block >= cex->ec_block && block < cex->ec_block + cex->ec_len) {
+ ex->ee_block = cpu_to_le32(cex->ec_block);
+ ext4_ext_store_pblock(ex, cex->ec_start);
+ ex->ee_len = cpu_to_le16(cex->ec_len);
+ ext_debug("%lu cached by %lu:%lu:%llu\n",
+ (unsigned long) block,
+ (unsigned long) cex->ec_block,
+ (unsigned long) cex->ec_len,
+ cex->ec_start);
+ return cex->ec_type;
+ }
+
+ /* not in cache */
+ return EXT4_EXT_CACHE_NO;
+}
+
+/*
+ * ext4_ext_rm_idx:
+ * removes index from the index block.
+ * It's used in truncate case only, thus all requests are for
+ * last index in the block only.
+ */
+int ext4_ext_rm_idx(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ struct buffer_head *bh;
+ int err;
+ ext4_fsblk_t leaf;
+
+ /* free index block */
+ path--;
+ leaf = idx_pblock(path->p_idx);
+ BUG_ON(path->p_hdr->eh_entries == 0);
+ if ((err = ext4_ext_get_access(handle, inode, path)))
+ return err;
+ path->p_hdr->eh_entries = cpu_to_le16(le16_to_cpu(path->p_hdr->eh_entries)-1);
+ if ((err = ext4_ext_dirty(handle, inode, path)))
+ return err;
+ ext_debug("index is empty, remove it, free block %llu\n", leaf);
+ bh = sb_find_get_block(inode->i_sb, leaf);
+ ext4_forget(handle, 1, inode, bh, leaf);
+ ext4_free_blocks(handle, inode, leaf, 1);
+ return err;
+}
+
+/*
+ * ext4_ext_calc_credits_for_insert:
+ * This routine returns max. credits that the extent tree can consume.
+ * It should be OK for low-performance paths like ->writepage()
+ * To allow many writing processes to fit into a single transaction,
+ * the caller should calculate credits under truncate_mutex and
+ * pass the actual path.
+ */
+int inline ext4_ext_calc_credits_for_insert(struct inode *inode,
+ struct ext4_ext_path *path)
+{
+ int depth, needed;
+
+ if (path) {
+ /* probably there is space in leaf? */
+ depth = ext_depth(inode);
+ if (le16_to_cpu(path[depth].p_hdr->eh_entries)
+ < le16_to_cpu(path[depth].p_hdr->eh_max))
+ return 1;
+ }
+
+ /*
+ * given 32-bit logical block (4294967296 blocks), max. tree
+ * can be 4 levels in depth -- 4 * 340^4 == 53453440000.
+ * Let's also add one more level for imbalance.
+ */
+ depth = 5;
+
+ /* allocation of new data block(s) */
+ needed = 2;
+
+ /*
+ * tree can be full, so it would need to grow in depth:
+ * allocation + old root + new root
+ */
+ needed += 2 + 1 + 1;
+
+ /*
+ * Index split can happen, we would need:
+ * allocate intermediate indexes (bitmap + group)
+ * + change two blocks at each level, but root (already included)
+ */
+ needed = (depth * 2) + (depth * 2);
+
+ /* any allocation modifies superblock */
+ needed += 1;
+
+ return needed;
+}
+
+static int ext4_remove_blocks(handle_t *handle, struct inode *inode,
+ struct ext4_extent *ex,
+ unsigned long from, unsigned long to)
+{
+ struct buffer_head *bh;
+ int i;
+
+#ifdef EXTENTS_STATS
+ {
+ struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
+ unsigned short ee_len = le16_to_cpu(ex->ee_len);
+ spin_lock(&sbi->s_ext_stats_lock);
+ sbi->s_ext_blocks += ee_len;
+ sbi->s_ext_extents++;
+ if (ee_len < sbi->s_ext_min)
+ sbi->s_ext_min = ee_len;
+ if (ee_len > sbi->s_ext_max)
+ sbi->s_ext_max = ee_len;
+ if (ext_depth(inode) > sbi->s_depth_max)
+ sbi->s_depth_max = ext_depth(inode);
+ spin_unlock(&sbi->s_ext_stats_lock);
+ }
+#endif
+ if (from >= le32_to_cpu(ex->ee_block)
+ && to == le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
+ /* tail removal */
+ unsigned long num;
+ ext4_fsblk_t start;
+ num = le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - from;
+ start = ext_pblock(ex) + le16_to_cpu(ex->ee_len) - num;
+ ext_debug("free last %lu blocks starting %llu\n", num, start);
+ for (i = 0; i < num; i++) {
+ bh = sb_find_get_block(inode->i_sb, start + i);
+ ext4_forget(handle, 0, inode, bh, start + i);
+ }
+ ext4_free_blocks(handle, inode, start, num);
+ } else if (from == le32_to_cpu(ex->ee_block)
+ && to <= le32_to_cpu(ex->ee_block) + le16_to_cpu(ex->ee_len) - 1) {
+ printk("strange request: removal %lu-%lu from %u:%u\n",
+ from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
+ } else {
+ printk("strange request: removal(2) %lu-%lu from %u:%u\n",
+ from, to, le32_to_cpu(ex->ee_block), le16_to_cpu(ex->ee_len));
+ }
+ return 0;
+}
+
+static int
+ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
+ struct ext4_ext_path *path, unsigned long start)
+{
+ int err = 0, correct_index = 0;
+ int depth = ext_depth(inode), credits;
+ struct ext4_extent_header *eh;
+ unsigned a, b, block, num;
+ unsigned long ex_ee_block;
+ unsigned short ex_ee_len;
+ struct ext4_extent *ex;
+
+ ext_debug("truncate since %lu in leaf\n", start);
+ if (!path[depth].p_hdr)
+ path[depth].p_hdr = ext_block_hdr(path[depth].p_bh);
+ eh = path[depth].p_hdr;
+ BUG_ON(eh == NULL);
+ BUG_ON(le16_to_cpu(eh->eh_entries) > le16_to_cpu(eh->eh_max));
+ BUG_ON(eh->eh_magic != EXT4_EXT_MAGIC);
+
+ /* find where to start removing */
+ ex = EXT_LAST_EXTENT(eh);
+
+ ex_ee_block = le32_to_cpu(ex->ee_block);
+ ex_ee_len = le16_to_cpu(ex->ee_len);
+
+ while (ex >= EXT_FIRST_EXTENT(eh) &&
+ ex_ee_block + ex_ee_len > start) {
+ ext_debug("remove ext %lu:%u\n", ex_ee_block, ex_ee_len);
+ path[depth].p_ext = ex;
+
+ a = ex_ee_block > start ? ex_ee_block : start;
+ b = ex_ee_block + ex_ee_len - 1 < EXT_MAX_BLOCK ?
+ ex_ee_block + ex_ee_len - 1 : EXT_MAX_BLOCK;
+
+ ext_debug(" border %u:%u\n", a, b);
+
+ if (a != ex_ee_block && b != ex_ee_block + ex_ee_len - 1) {
+ block = 0;
+ num = 0;
+ BUG();
+ } else if (a != ex_ee_block) {
+ /* remove tail of the extent */
+ block = ex_ee_block;
+ num = a - block;
+ } else if (b != ex_ee_block + ex_ee_len - 1) {
+ /* remove head of the extent */
+ block = a;
+ num = b - a;
+ /* there is no "make a hole" API yet */
+ BUG();
+ } else {
+ /* remove whole extent: excellent! */
+ block = ex_ee_block;
+ num = 0;
+ BUG_ON(a != ex_ee_block);
+ BUG_ON(b != ex_ee_block + ex_ee_len - 1);
+ }
+
+ /* at present, extent can't cross block group: */
+ /* leaf + bitmap + group desc + sb + inode */
+ credits = 5;
+ if (ex == EXT_FIRST_EXTENT(eh)) {
+ correct_index = 1;
+ credits += (ext_depth(inode)) + 1;
+ }
+#ifdef CONFIG_QUOTA
+ credits += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+#endif
+
+ handle = ext4_ext_journal_restart(handle, credits);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ goto out;
+ }
+
+ err = ext4_ext_get_access(handle, inode, path + depth);
+ if (err)
+ goto out;
+
+ err = ext4_remove_blocks(handle, inode, ex, a, b);
+ if (err)
+ goto out;
+
+ if (num == 0) {
+ /* this extent is removed; mark slot entirely unused */
+ ext4_ext_store_pblock(ex, 0);
+ eh->eh_entries = cpu_to_le16(le16_to_cpu(eh->eh_entries)-1);
+ }
+
+ ex->ee_block = cpu_to_le32(block);
+ ex->ee_len = cpu_to_le16(num);
+
+ err = ext4_ext_dirty(handle, inode, path + depth);
+ if (err)
+ goto out;
+
+ ext_debug("new extent: %u:%u:%llu\n", block, num,
+ ext_pblock(ex));
+ ex--;
+ ex_ee_block = le32_to_cpu(ex->ee_block);
+ ex_ee_len = le16_to_cpu(ex->ee_len);
+ }
+
+ if (correct_index && eh->eh_entries)
+ err = ext4_ext_correct_indexes(handle, inode, path);
+
+ /* if this leaf is free, then we should
+ * remove it from index block above */
+ if (err == 0 && eh->eh_entries == 0 && path[depth].p_bh != NULL)
+ err = ext4_ext_rm_idx(handle, inode, path + depth);
+
+out:
+ return err;
+}
+
+/*
+ * ext4_ext_more_to_rm:
+ * returns 1 if current index has to be freed (even partial)
+ */
+static int inline
+ext4_ext_more_to_rm(struct ext4_ext_path *path)
+{
+ BUG_ON(path->p_idx == NULL);
+
+ if (path->p_idx < EXT_FIRST_INDEX(path->p_hdr))
+ return 0;
+
+ /*
+ * if truncate on deeper level happened, it wasn't partial,
+ * so we have to consider current index for truncation
+ */
+ if (le16_to_cpu(path->p_hdr->eh_entries) == path->p_block)
+ return 0;
+ return 1;
+}
+
+int ext4_ext_remove_space(struct inode *inode, unsigned long start)
+{
+ struct super_block *sb = inode->i_sb;
+ int depth = ext_depth(inode);
+ struct ext4_ext_path *path;
+ handle_t *handle;
+ int i = 0, err = 0;
+
+ ext_debug("truncate since %lu\n", start);
+
+ /* probably first extent we're gonna free will be last in block */
+ handle = ext4_journal_start(inode, depth + 1);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ ext4_ext_invalidate_cache(inode);
+
+ /*
+ * We start scanning from right side, freeing all the blocks
+ * after i_size and walking into the tree depth-wise.
+ */
+ path = kmalloc(sizeof(struct ext4_ext_path) * (depth + 1), GFP_KERNEL);
+ if (path == NULL) {
+ ext4_journal_stop(handle);
+ return -ENOMEM;
+ }
+ memset(path, 0, sizeof(struct ext4_ext_path) * (depth + 1));
+ path[0].p_hdr = ext_inode_hdr(inode);
+ if (ext4_ext_check_header(__FUNCTION__, inode, path[0].p_hdr)) {
+ err = -EIO;
+ goto out;
+ }
+ path[0].p_depth = depth;
+
+ while (i >= 0 && err == 0) {
+ if (i == depth) {
+ /* this is leaf block */
+ err = ext4_ext_rm_leaf(handle, inode, path, start);
+ /* root level has p_bh == NULL, brelse() eats this */
+ brelse(path[i].p_bh);
+ path[i].p_bh = NULL;
+ i--;
+ continue;
+ }
+
+ /* this is index block */
+ if (!path[i].p_hdr) {
+ ext_debug("initialize header\n");
+ path[i].p_hdr = ext_block_hdr(path[i].p_bh);
+ if (ext4_ext_check_header(__FUNCTION__, inode,
+ path[i].p_hdr)) {
+ err = -EIO;
+ goto out;
+ }
+ }
+
+ BUG_ON(le16_to_cpu(path[i].p_hdr->eh_entries)
+ > le16_to_cpu(path[i].p_hdr->eh_max));
+ BUG_ON(path[i].p_hdr->eh_magic != EXT4_EXT_MAGIC);
+
+ if (!path[i].p_idx) {
+ /* this level hasn't been touched yet */
+ path[i].p_idx = EXT_LAST_INDEX(path[i].p_hdr);
+ path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries)+1;
+ ext_debug("init index ptr: hdr 0x%p, num %d\n",
+ path[i].p_hdr,
+ le16_to_cpu(path[i].p_hdr->eh_entries));
+ } else {
+ /* we were already here, see at next index */
+ path[i].p_idx--;
+ }
+
+ ext_debug("level %d - index, first 0x%p, cur 0x%p\n",
+ i, EXT_FIRST_INDEX(path[i].p_hdr),
+ path[i].p_idx);
+ if (ext4_ext_more_to_rm(path + i)) {
+ /* go to the next level */
+ ext_debug("move to level %d (block %llu)\n",
+ i + 1, idx_pblock(path[i].p_idx));
+ memset(path + i + 1, 0, sizeof(*path));
+ path[i+1].p_bh =
+ sb_bread(sb, idx_pblock(path[i].p_idx));
+ if (!path[i+1].p_bh) {
+ /* should we reset i_size? */
+ err = -EIO;
+ break;
+ }
+
+ /* save actual number of indexes since this
+ * number is changed at the next iteration */
+ path[i].p_block = le16_to_cpu(path[i].p_hdr->eh_entries);
+ i++;
+ } else {
+ /* we finished processing this index, go up */
+ if (path[i].p_hdr->eh_entries == 0 && i > 0) {
+ /* index is empty, remove it;
+ * handle must be already prepared by the
+ * truncatei_leaf() */
+ err = ext4_ext_rm_idx(handle, inode, path + i);
+ }
+ /* root level has p_bh == NULL, brelse() eats this */
+ brelse(path[i].p_bh);
+ path[i].p_bh = NULL;
+ i--;
+ ext_debug("return to level %d\n", i);
+ }
+ }
+
+ /* TODO: flexible tree reduction should be here */
+ if (path->p_hdr->eh_entries == 0) {
+ /*
+ * truncate to zero freed all the tree,
+ * so we need to correct eh_depth
+ */
+ err = ext4_ext_get_access(handle, inode, path);
+ if (err == 0) {
+ ext_inode_hdr(inode)->eh_depth = 0;
+ ext_inode_hdr(inode)->eh_max =
+ cpu_to_le16(ext4_ext_space_root(inode));
+ err = ext4_ext_dirty(handle, inode, path);
+ }
+ }
+out:
+ ext4_ext_tree_changed(inode);
+ ext4_ext_drop_refs(path);
+ kfree(path);
+ ext4_journal_stop(handle);
+
+ return err;
+}
+
+/*
+ * called at mount time
+ */
+void ext4_ext_init(struct super_block *sb)
+{
+ /*
+ * possible initialization would be here
+ */
+
+ if (test_opt(sb, EXTENTS)) {
+ printk("EXT4-fs: file extents enabled");
+#ifdef AGRESSIVE_TEST
+ printk(", agressive tests");
+#endif
+#ifdef CHECK_BINSEARCH
+ printk(", check binsearch");
+#endif
+#ifdef EXTENTS_STATS
+ printk(", stats");
+#endif
+ printk("\n");
+#ifdef EXTENTS_STATS
+ spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
+ EXT4_SB(sb)->s_ext_min = 1 << 30;
+ EXT4_SB(sb)->s_ext_max = 0;
+#endif
+ }
+}
+
+/*
+ * called at umount time
+ */
+void ext4_ext_release(struct super_block *sb)
+{
+ if (!test_opt(sb, EXTENTS))
+ return;
+
+#ifdef EXTENTS_STATS
+ if (EXT4_SB(sb)->s_ext_blocks && EXT4_SB(sb)->s_ext_extents) {
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ printk(KERN_ERR "EXT4-fs: %lu blocks in %lu extents (%lu ave)\n",
+ sbi->s_ext_blocks, sbi->s_ext_extents,
+ sbi->s_ext_blocks / sbi->s_ext_extents);
+ printk(KERN_ERR "EXT4-fs: extents: %lu min, %lu max, max depth %lu\n",
+ sbi->s_ext_min, sbi->s_ext_max, sbi->s_depth_max);
+ }
+#endif
+}
+
+int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
+ ext4_fsblk_t iblock,
+ unsigned long max_blocks, struct buffer_head *bh_result,
+ int create, int extend_disksize)
+{
+ struct ext4_ext_path *path = NULL;
+ struct ext4_extent newex, *ex;
+ ext4_fsblk_t goal, newblock;
+ int err = 0, depth;
+ unsigned long allocated = 0;
+
+ __clear_bit(BH_New, &bh_result->b_state);
+ ext_debug("blocks %d/%lu requested for inode %u\n", (int) iblock,
+ max_blocks, (unsigned) inode->i_ino);
+ mutex_lock(&EXT4_I(inode)->truncate_mutex);
+
+ /* check in cache */
+ if ((goal = ext4_ext_in_cache(inode, iblock, &newex))) {
+ if (goal == EXT4_EXT_CACHE_GAP) {
+ if (!create) {
+ /* block isn't allocated yet and
+ * user doesn't want to allocate it */
+ goto out2;
+ }
+ /* we should allocate requested block */
+ } else if (goal == EXT4_EXT_CACHE_EXTENT) {
+ /* block is already allocated */
+ newblock = iblock
+ - le32_to_cpu(newex.ee_block)
+ + ext_pblock(&newex);
+ /* number of remaining blocks in the extent */
+ allocated = le16_to_cpu(newex.ee_len) -
+ (iblock - le32_to_cpu(newex.ee_block));
+ goto out;
+ } else {
+ BUG();
+ }
+ }
+
+ /* find extent for this block */
+ path = ext4_ext_find_extent(inode, iblock, NULL);
+ if (IS_ERR(path)) {
+ err = PTR_ERR(path);
+ path = NULL;
+ goto out2;
+ }
+
+ depth = ext_depth(inode);
+
+ /*
+ * consistent leaf must not be empty;
+ * this situation is possible, though, _during_ tree modification;
+ * this is why assert can't be put in ext4_ext_find_extent()
+ */
+ BUG_ON(path[depth].p_ext == NULL && depth != 0);
+
+ if ((ex = path[depth].p_ext)) {
+ unsigned long ee_block = le32_to_cpu(ex->ee_block);
+ ext4_fsblk_t ee_start = ext_pblock(ex);
+ unsigned short ee_len = le16_to_cpu(ex->ee_len);
+
+ /*
+ * Allow future support for preallocated extents to be added
+ * as an RO_COMPAT feature:
+ * Uninitialized extents are treated as holes, except that
+ * we avoid (fail) allocating new blocks during a write.
+ */
+ if (ee_len > EXT_MAX_LEN)
+ goto out2;
+ /* if found extent covers block, simply return it */
+ if (iblock >= ee_block && iblock < ee_block + ee_len) {
+ newblock = iblock - ee_block + ee_start;
+ /* number of remaining blocks in the extent */
+ allocated = ee_len - (iblock - ee_block);
+ ext_debug("%d fit into %lu:%d -> %llu\n", (int) iblock,
+ ee_block, ee_len, newblock);
+ ext4_ext_put_in_cache(inode, ee_block, ee_len,
+ ee_start, EXT4_EXT_CACHE_EXTENT);
+ goto out;
+ }
+ }
+
+ /*
+ * requested block isn't allocated yet;
+ * we couldn't try to create block if create flag is zero
+ */
+ if (!create) {
+ /* put just found gap into cache to speed up
+ * subsequent requests */
+ ext4_ext_put_gap_in_cache(inode, path, iblock);
+ goto out2;
+ }
+ /*
+ * Okay, we need to do block allocation. Lazily initialize the block
+ * allocation info here if necessary.
+ */
+ if (S_ISREG(inode->i_mode) && (!EXT4_I(inode)->i_block_alloc_info))
+ ext4_init_block_alloc_info(inode);
+
+ /* allocate new block */
+ goal = ext4_ext_find_goal(inode, path, iblock);
+ allocated = max_blocks;
+ newblock = ext4_new_blocks(handle, inode, goal, &allocated, &err);
+ if (!newblock)
+ goto out2;
+ ext_debug("allocate new block: goal %llu, found %llu/%lu\n",
+ goal, newblock, allocated);
+
+ /* try to insert new extent into found leaf and return */
+ newex.ee_block = cpu_to_le32(iblock);
+ ext4_ext_store_pblock(&newex, newblock);
+ newex.ee_len = cpu_to_le16(allocated);
+ err = ext4_ext_insert_extent(handle, inode, path, &newex);
+ if (err)
+ goto out2;
+
+ if (extend_disksize && inode->i_size > EXT4_I(inode)->i_disksize)
+ EXT4_I(inode)->i_disksize = inode->i_size;
+
+ /* previous routine could use block we allocated */
+ newblock = ext_pblock(&newex);
+ __set_bit(BH_New, &bh_result->b_state);
+
+ ext4_ext_put_in_cache(inode, iblock, allocated, newblock,
+ EXT4_EXT_CACHE_EXTENT);
+out:
+ if (allocated > max_blocks)
+ allocated = max_blocks;
+ ext4_ext_show_leaf(inode, path);
+ __set_bit(BH_Mapped, &bh_result->b_state);
+ bh_result->b_bdev = inode->i_sb->s_bdev;
+ bh_result->b_blocknr = newblock;
+out2:
+ if (path) {
+ ext4_ext_drop_refs(path);
+ kfree(path);
+ }
+ mutex_unlock(&EXT4_I(inode)->truncate_mutex);
+
+ return err ? err : allocated;
+}
+
+void ext4_ext_truncate(struct inode * inode, struct page *page)
+{
+ struct address_space *mapping = inode->i_mapping;
+ struct super_block *sb = inode->i_sb;
+ unsigned long last_block;
+ handle_t *handle;
+ int err = 0;
+
+ /*
+ * probably first extent we're gonna free will be last in block
+ */
+ err = ext4_writepage_trans_blocks(inode) + 3;
+ handle = ext4_journal_start(inode, err);
+ if (IS_ERR(handle)) {
+ if (page) {
+ clear_highpage(page);
+ flush_dcache_page(page);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ return;
+ }
+
+ if (page)
+ ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+
+ mutex_lock(&EXT4_I(inode)->truncate_mutex);
+ ext4_ext_invalidate_cache(inode);
+
+ /*
+ * TODO: optimization is possible here.
+ * Probably we need not scan at all,
+ * because page truncation is enough.
+ */
+ if (ext4_orphan_add(handle, inode))
+ goto out_stop;
+
+ /* we have to know where to truncate from in crash case */
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ ext4_mark_inode_dirty(handle, inode);
+
+ last_block = (inode->i_size + sb->s_blocksize - 1)
+ >> EXT4_BLOCK_SIZE_BITS(sb);
+ err = ext4_ext_remove_space(inode, last_block);
+
+ /* In a multi-transaction truncate, we only make the final
+ * transaction synchronous. */
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+
+out_stop:
+ /*
+ * If this was a simple ftruncate() and the file will remain alive,
+ * then we need to clear up the orphan record which we created above.
+ * However, if this was a real unlink then we were called by
+ * ext4_delete_inode(), and we allow that function to clean up the
+ * orphan info for us.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(handle, inode);
+
+ mutex_unlock(&EXT4_I(inode)->truncate_mutex);
+ ext4_journal_stop(handle);
+}
+
+/*
+ * ext4_ext_writepage_trans_blocks:
+ * calculate max number of blocks we could modify
+ * in order to allocate new block for an inode
+ */
+int ext4_ext_writepage_trans_blocks(struct inode *inode, int num)
+{
+ int needed;
+
+ needed = ext4_ext_calc_credits_for_insert(inode, NULL);
+
+ /* caller wants to allocate num blocks, but note it includes sb */
+ needed = needed * num - (num - 1);
+
+#ifdef CONFIG_QUOTA
+ needed += 2 * EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+#endif
+
+ return needed;
+}
+
+EXPORT_SYMBOL(ext4_mark_inode_dirty);
+EXPORT_SYMBOL(ext4_ext_invalidate_cache);
+EXPORT_SYMBOL(ext4_ext_insert_extent);
+EXPORT_SYMBOL(ext4_ext_walk_space);
+EXPORT_SYMBOL(ext4_ext_find_goal);
+EXPORT_SYMBOL(ext4_ext_calc_credits_for_insert);
+
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
new file mode 100644
index 000000000000..0b622c0624b7
--- /dev/null
+++ b/fs/ext4/file.c
@@ -0,0 +1,139 @@
+/*
+ * linux/fs/ext4/file.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/file.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * ext4 fs regular file handling primitives
+ *
+ * 64-bit file support on 64-bit platforms by Jakub Jelinek
+ * (jj@sunsite.ms.mff.cuni.cz)
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include "xattr.h"
+#include "acl.h"
+
+/*
+ * Called when an inode is released. Note that this is different
+ * from ext4_file_open: open gets called at every open, but release
+ * gets called only when /all/ the files are closed.
+ */
+static int ext4_release_file (struct inode * inode, struct file * filp)
+{
+ /* if we are the last writer on the inode, drop the block reservation */
+ if ((filp->f_mode & FMODE_WRITE) &&
+ (atomic_read(&inode->i_writecount) == 1))
+ {
+ mutex_lock(&EXT4_I(inode)->truncate_mutex);
+ ext4_discard_reservation(inode);
+ mutex_unlock(&EXT4_I(inode)->truncate_mutex);
+ }
+ if (is_dx(inode) && filp->private_data)
+ ext4_htree_free_dir_info(filp->private_data);
+
+ return 0;
+}
+
+static ssize_t
+ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file->f_dentry->d_inode;
+ ssize_t ret;
+ int err;
+
+ ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
+
+ /*
+ * Skip flushing if there was an error, or if nothing was written.
+ */
+ if (ret <= 0)
+ return ret;
+
+ /*
+ * If the inode is IS_SYNC, or is O_SYNC and we are doing data
+ * journalling then we need to make sure that we force the transaction
+ * to disk to keep all metadata uptodate synchronously.
+ */
+ if (file->f_flags & O_SYNC) {
+ /*
+ * If we are non-data-journaled, then the dirty data has
+ * already been flushed to backing store by generic_osync_inode,
+ * and the inode has been flushed too if there have been any
+ * modifications other than mere timestamp updates.
+ *
+ * Open question --- do we care about flushing timestamps too
+ * if the inode is IS_SYNC?
+ */
+ if (!ext4_should_journal_data(inode))
+ return ret;
+
+ goto force_commit;
+ }
+
+ /*
+ * So we know that there has been no forced data flush. If the inode
+ * is marked IS_SYNC, we need to force one ourselves.
+ */
+ if (!IS_SYNC(inode))
+ return ret;
+
+ /*
+ * Open question #2 --- should we force data to disk here too? If we
+ * don't, the only impact is that data=writeback filesystems won't
+ * flush data to disk automatically on IS_SYNC, only metadata (but
+ * historically, that is what ext2 has done.)
+ */
+
+force_commit:
+ err = ext4_force_commit(inode->i_sb);
+ if (err)
+ return err;
+ return ret;
+}
+
+const struct file_operations ext4_file_operations = {
+ .llseek = generic_file_llseek,
+ .read = do_sync_read,
+ .write = do_sync_write,
+ .aio_read = generic_file_aio_read,
+ .aio_write = ext4_file_write,
+ .ioctl = ext4_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = ext4_compat_ioctl,
+#endif
+ .mmap = generic_file_mmap,
+ .open = generic_file_open,
+ .release = ext4_release_file,
+ .fsync = ext4_sync_file,
+ .sendfile = generic_file_sendfile,
+ .splice_read = generic_file_splice_read,
+ .splice_write = generic_file_splice_write,
+};
+
+struct inode_operations ext4_file_inode_operations = {
+ .truncate = ext4_truncate,
+ .setattr = ext4_setattr,
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = ext4_listxattr,
+ .removexattr = generic_removexattr,
+#endif
+ .permission = ext4_permission,
+};
+
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
new file mode 100644
index 000000000000..2a167d7131fa
--- /dev/null
+++ b/fs/ext4/fsync.c
@@ -0,0 +1,88 @@
+/*
+ * linux/fs/ext4/fsync.c
+ *
+ * Copyright (C) 1993 Stephen Tweedie (sct@redhat.com)
+ * from
+ * Copyright (C) 1992 Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ * from
+ * linux/fs/minix/truncate.c Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * ext4fs fsync primitive
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ *
+ * Removed unnecessary code duplication for little endian machines
+ * and excessive __inline__s.
+ * Andi Kleen, 1997
+ *
+ * Major simplications and cleanup - we only need to do the metadata, because
+ * we can depend on generic_block_fdatasync() to sync the data blocks.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/writeback.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+
+/*
+ * akpm: A new design for ext4_sync_file().
+ *
+ * This is only called from sys_fsync(), sys_fdatasync() and sys_msync().
+ * There cannot be a transaction open by this task.
+ * Another task could have dirtied this inode. Its data can be in any
+ * state in the journalling system.
+ *
+ * What we do is just kick off a commit and wait on it. This will snapshot the
+ * inode to disk.
+ */
+
+int ext4_sync_file(struct file * file, struct dentry *dentry, int datasync)
+{
+ struct inode *inode = dentry->d_inode;
+ int ret = 0;
+
+ J_ASSERT(ext4_journal_current_handle() == 0);
+
+ /*
+ * data=writeback:
+ * The caller's filemap_fdatawrite()/wait will sync the data.
+ * sync_inode() will sync the metadata
+ *
+ * data=ordered:
+ * The caller's filemap_fdatawrite() will write the data and
+ * sync_inode() will write the inode if it is dirty. Then the caller's
+ * filemap_fdatawait() will wait on the pages.
+ *
+ * data=journal:
+ * filemap_fdatawrite won't do anything (the buffers are clean).
+ * ext4_force_commit will write the file data into the journal and
+ * will wait on that.
+ * filemap_fdatawait() will encounter a ton of newly-dirtied pages
+ * (they were dirtied by commit). But that's OK - the blocks are
+ * safe in-journal, which is all fsync() needs to ensure.
+ */
+ if (ext4_should_journal_data(inode)) {
+ ret = ext4_force_commit(inode->i_sb);
+ goto out;
+ }
+
+ /*
+ * The VFS has written the file data. If the inode is unaltered
+ * then we need not start a commit.
+ */
+ if (inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC)) {
+ struct writeback_control wbc = {
+ .sync_mode = WB_SYNC_ALL,
+ .nr_to_write = 0, /* sys_fsync did this */
+ };
+ ret = sync_inode(inode, &wbc);
+ }
+out:
+ return ret;
+}
diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c
new file mode 100644
index 000000000000..a67966385e06
--- /dev/null
+++ b/fs/ext4/hash.c
@@ -0,0 +1,152 @@
+/*
+ * linux/fs/ext4/hash.c
+ *
+ * Copyright (C) 2002 by Theodore Ts'o
+ *
+ * This file is released under the GPL v2.
+ *
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ */
+
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/sched.h>
+#include <linux/ext4_fs.h>
+#include <linux/cryptohash.h>
+
+#define DELTA 0x9E3779B9
+
+static void TEA_transform(__u32 buf[4], __u32 const in[])
+{
+ __u32 sum = 0;
+ __u32 b0 = buf[0], b1 = buf[1];
+ __u32 a = in[0], b = in[1], c = in[2], d = in[3];
+ int n = 16;
+
+ do {
+ sum += DELTA;
+ b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b);
+ b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d);
+ } while(--n);
+
+ buf[0] += b0;
+ buf[1] += b1;
+}
+
+
+/* The old legacy hash */
+static __u32 dx_hack_hash (const char *name, int len)
+{
+ __u32 hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9;
+ while (len--) {
+ __u32 hash = hash1 + (hash0 ^ (*name++ * 7152373));
+
+ if (hash & 0x80000000) hash -= 0x7fffffff;
+ hash1 = hash0;
+ hash0 = hash;
+ }
+ return (hash0 << 1);
+}
+
+static void str2hashbuf(const char *msg, int len, __u32 *buf, int num)
+{
+ __u32 pad, val;
+ int i;
+
+ pad = (__u32)len | ((__u32)len << 8);
+ pad |= pad << 16;
+
+ val = pad;
+ if (len > num*4)
+ len = num * 4;
+ for (i=0; i < len; i++) {
+ if ((i % 4) == 0)
+ val = pad;
+ val = msg[i] + (val << 8);
+ if ((i % 4) == 3) {
+ *buf++ = val;
+ val = pad;
+ num--;
+ }
+ }
+ if (--num >= 0)
+ *buf++ = val;
+ while (--num >= 0)
+ *buf++ = pad;
+}
+
+/*
+ * Returns the hash of a filename. If len is 0 and name is NULL, then
+ * this function can be used to test whether or not a hash version is
+ * supported.
+ *
+ * The seed is an 4 longword (32 bits) "secret" which can be used to
+ * uniquify a hash. If the seed is all zero's, then some default seed
+ * may be used.
+ *
+ * A particular hash version specifies whether or not the seed is
+ * represented, and whether or not the returned hash is 32 bits or 64
+ * bits. 32 bit hashes will return 0 for the minor hash.
+ */
+int ext4fs_dirhash(const char *name, int len, struct dx_hash_info *hinfo)
+{
+ __u32 hash;
+ __u32 minor_hash = 0;
+ const char *p;
+ int i;
+ __u32 in[8], buf[4];
+
+ /* Initialize the default seed for the hash checksum functions */
+ buf[0] = 0x67452301;
+ buf[1] = 0xefcdab89;
+ buf[2] = 0x98badcfe;
+ buf[3] = 0x10325476;
+
+ /* Check to see if the seed is all zero's */
+ if (hinfo->seed) {
+ for (i=0; i < 4; i++) {
+ if (hinfo->seed[i])
+ break;
+ }
+ if (i < 4)
+ memcpy(buf, hinfo->seed, sizeof(buf));
+ }
+
+ switch (hinfo->hash_version) {
+ case DX_HASH_LEGACY:
+ hash = dx_hack_hash(name, len);
+ break;
+ case DX_HASH_HALF_MD4:
+ p = name;
+ while (len > 0) {
+ str2hashbuf(p, len, in, 8);
+ half_md4_transform(buf, in);
+ len -= 32;
+ p += 32;
+ }
+ minor_hash = buf[2];
+ hash = buf[1];
+ break;
+ case DX_HASH_TEA:
+ p = name;
+ while (len > 0) {
+ str2hashbuf(p, len, in, 4);
+ TEA_transform(buf, in);
+ len -= 16;
+ p += 16;
+ }
+ hash = buf[0];
+ minor_hash = buf[1];
+ break;
+ default:
+ hinfo->hash = 0;
+ return -1;
+ }
+ hash = hash & ~1;
+ if (hash == (EXT4_HTREE_EOF << 1))
+ hash = (EXT4_HTREE_EOF-1) << 1;
+ hinfo->hash = hash;
+ hinfo->minor_hash = minor_hash;
+ return 0;
+}
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
new file mode 100644
index 000000000000..c88b439ba5cd
--- /dev/null
+++ b/fs/ext4/ialloc.c
@@ -0,0 +1,772 @@
+/*
+ * linux/fs/ext4/ialloc.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * BSD ufs-inspired inode and directory allocation by
+ * Stephen Tweedie (sct@redhat.com), 1993
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/quotaops.h>
+#include <linux/buffer_head.h>
+#include <linux/random.h>
+#include <linux/bitops.h>
+#include <linux/blkdev.h>
+#include <asm/byteorder.h>
+
+#include "xattr.h"
+#include "acl.h"
+
+/*
+ * ialloc.c contains the inodes allocation and deallocation routines
+ */
+
+/*
+ * The free inodes are managed by bitmaps. A file system contains several
+ * blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
+ * block for inodes, N blocks for the inode table and data blocks.
+ *
+ * The file system contains group descriptors which are located after the
+ * super block. Each descriptor contains the number of the bitmap block and
+ * the free blocks count in the block.
+ */
+
+
+/*
+ * Read the inode allocation bitmap for a given block_group, reading
+ * into the specified slot in the superblock's bitmap cache.
+ *
+ * Return buffer_head of bitmap on success or NULL.
+ */
+static struct buffer_head *
+read_inode_bitmap(struct super_block * sb, unsigned long block_group)
+{
+ struct ext4_group_desc *desc;
+ struct buffer_head *bh = NULL;
+
+ desc = ext4_get_group_desc(sb, block_group, NULL);
+ if (!desc)
+ goto error_out;
+
+ bh = sb_bread(sb, ext4_inode_bitmap(sb, desc));
+ if (!bh)
+ ext4_error(sb, "read_inode_bitmap",
+ "Cannot read inode bitmap - "
+ "block_group = %lu, inode_bitmap = %llu",
+ block_group, ext4_inode_bitmap(sb, desc));
+error_out:
+ return bh;
+}
+
+/*
+ * NOTE! When we get the inode, we're the only people
+ * that have access to it, and as such there are no
+ * race conditions we have to worry about. The inode
+ * is not on the hash-lists, and it cannot be reached
+ * through the filesystem because the directory entry
+ * has been deleted earlier.
+ *
+ * HOWEVER: we must make sure that we get no aliases,
+ * which means that we have to call "clear_inode()"
+ * _before_ we mark the inode not in use in the inode
+ * bitmaps. Otherwise a newly created file might use
+ * the same inode number (not actually the same pointer
+ * though), and then we'd have two inodes sharing the
+ * same inode number and space on the harddisk.
+ */
+void ext4_free_inode (handle_t *handle, struct inode * inode)
+{
+ struct super_block * sb = inode->i_sb;
+ int is_directory;
+ unsigned long ino;
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *bh2;
+ unsigned long block_group;
+ unsigned long bit;
+ struct ext4_group_desc * gdp;
+ struct ext4_super_block * es;
+ struct ext4_sb_info *sbi;
+ int fatal = 0, err;
+
+ if (atomic_read(&inode->i_count) > 1) {
+ printk ("ext4_free_inode: inode has count=%d\n",
+ atomic_read(&inode->i_count));
+ return;
+ }
+ if (inode->i_nlink) {
+ printk ("ext4_free_inode: inode has nlink=%d\n",
+ inode->i_nlink);
+ return;
+ }
+ if (!sb) {
+ printk("ext4_free_inode: inode on nonexistent device\n");
+ return;
+ }
+ sbi = EXT4_SB(sb);
+
+ ino = inode->i_ino;
+ ext4_debug ("freeing inode %lu\n", ino);
+
+ /*
+ * Note: we must free any quota before locking the superblock,
+ * as writing the quota to disk may need the lock as well.
+ */
+ DQUOT_INIT(inode);
+ ext4_xattr_delete_inode(handle, inode);
+ DQUOT_FREE_INODE(inode);
+ DQUOT_DROP(inode);
+
+ is_directory = S_ISDIR(inode->i_mode);
+
+ /* Do this BEFORE marking the inode not in use or returning an error */
+ clear_inode (inode);
+
+ es = EXT4_SB(sb)->s_es;
+ if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
+ ext4_error (sb, "ext4_free_inode",
+ "reserved or nonexistent inode %lu", ino);
+ goto error_return;
+ }
+ block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
+ bitmap_bh = read_inode_bitmap(sb, block_group);
+ if (!bitmap_bh)
+ goto error_return;
+
+ BUFFER_TRACE(bitmap_bh, "get_write_access");
+ fatal = ext4_journal_get_write_access(handle, bitmap_bh);
+ if (fatal)
+ goto error_return;
+
+ /* Ok, now we can actually update the inode bitmaps.. */
+ if (!ext4_clear_bit_atomic(sb_bgl_lock(sbi, block_group),
+ bit, bitmap_bh->b_data))
+ ext4_error (sb, "ext4_free_inode",
+ "bit already cleared for inode %lu", ino);
+ else {
+ gdp = ext4_get_group_desc (sb, block_group, &bh2);
+
+ BUFFER_TRACE(bh2, "get_write_access");
+ fatal = ext4_journal_get_write_access(handle, bh2);
+ if (fatal) goto error_return;
+
+ if (gdp) {
+ spin_lock(sb_bgl_lock(sbi, block_group));
+ gdp->bg_free_inodes_count = cpu_to_le16(
+ le16_to_cpu(gdp->bg_free_inodes_count) + 1);
+ if (is_directory)
+ gdp->bg_used_dirs_count = cpu_to_le16(
+ le16_to_cpu(gdp->bg_used_dirs_count) - 1);
+ spin_unlock(sb_bgl_lock(sbi, block_group));
+ percpu_counter_inc(&sbi->s_freeinodes_counter);
+ if (is_directory)
+ percpu_counter_dec(&sbi->s_dirs_counter);
+
+ }
+ BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bh2);
+ if (!fatal) fatal = err;
+ }
+ BUFFER_TRACE(bitmap_bh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bitmap_bh);
+ if (!fatal)
+ fatal = err;
+ sb->s_dirt = 1;
+error_return:
+ brelse(bitmap_bh);
+ ext4_std_error(sb, fatal);
+}
+
+/*
+ * There are two policies for allocating an inode. If the new inode is
+ * a directory, then a forward search is made for a block group with both
+ * free space and a low directory-to-inode ratio; if that fails, then of
+ * the groups with above-average free space, that group with the fewest
+ * directories already is chosen.
+ *
+ * For other inodes, search forward from the parent directory\'s block
+ * group to find a free inode.
+ */
+static int find_group_dir(struct super_block *sb, struct inode *parent)
+{
+ int ngroups = EXT4_SB(sb)->s_groups_count;
+ unsigned int freei, avefreei;
+ struct ext4_group_desc *desc, *best_desc = NULL;
+ struct buffer_head *bh;
+ int group, best_group = -1;
+
+ freei = percpu_counter_read_positive(&EXT4_SB(sb)->s_freeinodes_counter);
+ avefreei = freei / ngroups;
+
+ for (group = 0; group < ngroups; group++) {
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (!desc || !desc->bg_free_inodes_count)
+ continue;
+ if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
+ continue;
+ if (!best_desc ||
+ (le16_to_cpu(desc->bg_free_blocks_count) >
+ le16_to_cpu(best_desc->bg_free_blocks_count))) {
+ best_group = group;
+ best_desc = desc;
+ }
+ }
+ return best_group;
+}
+
+/*
+ * Orlov's allocator for directories.
+ *
+ * We always try to spread first-level directories.
+ *
+ * If there are blockgroups with both free inodes and free blocks counts
+ * not worse than average we return one with smallest directory count.
+ * Otherwise we simply return a random group.
+ *
+ * For the rest rules look so:
+ *
+ * It's OK to put directory into a group unless
+ * it has too many directories already (max_dirs) or
+ * it has too few free inodes left (min_inodes) or
+ * it has too few free blocks left (min_blocks) or
+ * it's already running too large debt (max_debt).
+ * Parent's group is prefered, if it doesn't satisfy these
+ * conditions we search cyclically through the rest. If none
+ * of the groups look good we just look for a group with more
+ * free inodes than average (starting at parent's group).
+ *
+ * Debt is incremented each time we allocate a directory and decremented
+ * when we allocate an inode, within 0--255.
+ */
+
+#define INODE_COST 64
+#define BLOCK_COST 256
+
+static int find_group_orlov(struct super_block *sb, struct inode *parent)
+{
+ int parent_group = EXT4_I(parent)->i_block_group;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+ int ngroups = sbi->s_groups_count;
+ int inodes_per_group = EXT4_INODES_PER_GROUP(sb);
+ unsigned int freei, avefreei;
+ ext4_fsblk_t freeb, avefreeb;
+ ext4_fsblk_t blocks_per_dir;
+ unsigned int ndirs;
+ int max_debt, max_dirs, min_inodes;
+ ext4_grpblk_t min_blocks;
+ int group = -1, i;
+ struct ext4_group_desc *desc;
+ struct buffer_head *bh;
+
+ freei = percpu_counter_read_positive(&sbi->s_freeinodes_counter);
+ avefreei = freei / ngroups;
+ freeb = percpu_counter_read_positive(&sbi->s_freeblocks_counter);
+ avefreeb = freeb;
+ do_div(avefreeb, ngroups);
+ ndirs = percpu_counter_read_positive(&sbi->s_dirs_counter);
+
+ if ((parent == sb->s_root->d_inode) ||
+ (EXT4_I(parent)->i_flags & EXT4_TOPDIR_FL)) {
+ int best_ndir = inodes_per_group;
+ int best_group = -1;
+
+ get_random_bytes(&group, sizeof(group));
+ parent_group = (unsigned)group % ngroups;
+ for (i = 0; i < ngroups; i++) {
+ group = (parent_group + i) % ngroups;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (!desc || !desc->bg_free_inodes_count)
+ continue;
+ if (le16_to_cpu(desc->bg_used_dirs_count) >= best_ndir)
+ continue;
+ if (le16_to_cpu(desc->bg_free_inodes_count) < avefreei)
+ continue;
+ if (le16_to_cpu(desc->bg_free_blocks_count) < avefreeb)
+ continue;
+ best_group = group;
+ best_ndir = le16_to_cpu(desc->bg_used_dirs_count);
+ }
+ if (best_group >= 0)
+ return best_group;
+ goto fallback;
+ }
+
+ blocks_per_dir = ext4_blocks_count(es) - freeb;
+ do_div(blocks_per_dir, ndirs);
+
+ max_dirs = ndirs / ngroups + inodes_per_group / 16;
+ min_inodes = avefreei - inodes_per_group / 4;
+ min_blocks = avefreeb - EXT4_BLOCKS_PER_GROUP(sb) / 4;
+
+ max_debt = EXT4_BLOCKS_PER_GROUP(sb);
+ max_debt /= max_t(int, blocks_per_dir, BLOCK_COST);
+ if (max_debt * INODE_COST > inodes_per_group)
+ max_debt = inodes_per_group / INODE_COST;
+ if (max_debt > 255)
+ max_debt = 255;
+ if (max_debt == 0)
+ max_debt = 1;
+
+ for (i = 0; i < ngroups; i++) {
+ group = (parent_group + i) % ngroups;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (!desc || !desc->bg_free_inodes_count)
+ continue;
+ if (le16_to_cpu(desc->bg_used_dirs_count) >= max_dirs)
+ continue;
+ if (le16_to_cpu(desc->bg_free_inodes_count) < min_inodes)
+ continue;
+ if (le16_to_cpu(desc->bg_free_blocks_count) < min_blocks)
+ continue;
+ return group;
+ }
+
+fallback:
+ for (i = 0; i < ngroups; i++) {
+ group = (parent_group + i) % ngroups;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (!desc || !desc->bg_free_inodes_count)
+ continue;
+ if (le16_to_cpu(desc->bg_free_inodes_count) >= avefreei)
+ return group;
+ }
+
+ if (avefreei) {
+ /*
+ * The free-inodes counter is approximate, and for really small
+ * filesystems the above test can fail to find any blockgroups
+ */
+ avefreei = 0;
+ goto fallback;
+ }
+
+ return -1;
+}
+
+static int find_group_other(struct super_block *sb, struct inode *parent)
+{
+ int parent_group = EXT4_I(parent)->i_block_group;
+ int ngroups = EXT4_SB(sb)->s_groups_count;
+ struct ext4_group_desc *desc;
+ struct buffer_head *bh;
+ int group, i;
+
+ /*
+ * Try to place the inode in its parent directory
+ */
+ group = parent_group;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
+ le16_to_cpu(desc->bg_free_blocks_count))
+ return group;
+
+ /*
+ * We're going to place this inode in a different blockgroup from its
+ * parent. We want to cause files in a common directory to all land in
+ * the same blockgroup. But we want files which are in a different
+ * directory which shares a blockgroup with our parent to land in a
+ * different blockgroup.
+ *
+ * So add our directory's i_ino into the starting point for the hash.
+ */
+ group = (group + parent->i_ino) % ngroups;
+
+ /*
+ * Use a quadratic hash to find a group with a free inode and some free
+ * blocks.
+ */
+ for (i = 1; i < ngroups; i <<= 1) {
+ group += i;
+ if (group >= ngroups)
+ group -= ngroups;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
+ le16_to_cpu(desc->bg_free_blocks_count))
+ return group;
+ }
+
+ /*
+ * That failed: try linear search for a free inode, even if that group
+ * has no free blocks.
+ */
+ group = parent_group;
+ for (i = 0; i < ngroups; i++) {
+ if (++group >= ngroups)
+ group = 0;
+ desc = ext4_get_group_desc (sb, group, &bh);
+ if (desc && le16_to_cpu(desc->bg_free_inodes_count))
+ return group;
+ }
+
+ return -1;
+}
+
+/*
+ * There are two policies for allocating an inode. If the new inode is
+ * a directory, then a forward search is made for a block group with both
+ * free space and a low directory-to-inode ratio; if that fails, then of
+ * the groups with above-average free space, that group with the fewest
+ * directories already is chosen.
+ *
+ * For other inodes, search forward from the parent directory's block
+ * group to find a free inode.
+ */
+struct inode *ext4_new_inode(handle_t *handle, struct inode * dir, int mode)
+{
+ struct super_block *sb;
+ struct buffer_head *bitmap_bh = NULL;
+ struct buffer_head *bh2;
+ int group;
+ unsigned long ino = 0;
+ struct inode * inode;
+ struct ext4_group_desc * gdp = NULL;
+ struct ext4_super_block * es;
+ struct ext4_inode_info *ei;
+ struct ext4_sb_info *sbi;
+ int err = 0;
+ struct inode *ret;
+ int i;
+
+ /* Cannot create files in a deleted directory */
+ if (!dir || !dir->i_nlink)
+ return ERR_PTR(-EPERM);
+
+ sb = dir->i_sb;
+ inode = new_inode(sb);
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ ei = EXT4_I(inode);
+
+ sbi = EXT4_SB(sb);
+ es = sbi->s_es;
+ if (S_ISDIR(mode)) {
+ if (test_opt (sb, OLDALLOC))
+ group = find_group_dir(sb, dir);
+ else
+ group = find_group_orlov(sb, dir);
+ } else
+ group = find_group_other(sb, dir);
+
+ err = -ENOSPC;
+ if (group == -1)
+ goto out;
+
+ for (i = 0; i < sbi->s_groups_count; i++) {
+ err = -EIO;
+
+ gdp = ext4_get_group_desc(sb, group, &bh2);
+ if (!gdp)
+ goto fail;
+
+ brelse(bitmap_bh);
+ bitmap_bh = read_inode_bitmap(sb, group);
+ if (!bitmap_bh)
+ goto fail;
+
+ ino = 0;
+
+repeat_in_this_group:
+ ino = ext4_find_next_zero_bit((unsigned long *)
+ bitmap_bh->b_data, EXT4_INODES_PER_GROUP(sb), ino);
+ if (ino < EXT4_INODES_PER_GROUP(sb)) {
+
+ BUFFER_TRACE(bitmap_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bitmap_bh);
+ if (err)
+ goto fail;
+
+ if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group),
+ ino, bitmap_bh->b_data)) {
+ /* we won it */
+ BUFFER_TRACE(bitmap_bh,
+ "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle,
+ bitmap_bh);
+ if (err)
+ goto fail;
+ goto got;
+ }
+ /* we lost it */
+ jbd2_journal_release_buffer(handle, bitmap_bh);
+
+ if (++ino < EXT4_INODES_PER_GROUP(sb))
+ goto repeat_in_this_group;
+ }
+
+ /*
+ * This case is possible in concurrent environment. It is very
+ * rare. We cannot repeat the find_group_xxx() call because
+ * that will simply return the same blockgroup, because the
+ * group descriptor metadata has not yet been updated.
+ * So we just go onto the next blockgroup.
+ */
+ if (++group == sbi->s_groups_count)
+ group = 0;
+ }
+ err = -ENOSPC;
+ goto out;
+
+got:
+ ino += group * EXT4_INODES_PER_GROUP(sb) + 1;
+ if (ino < EXT4_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
+ ext4_error (sb, "ext4_new_inode",
+ "reserved inode or inode > inodes count - "
+ "block_group = %d, inode=%lu", group, ino);
+ err = -EIO;
+ goto fail;
+ }
+
+ BUFFER_TRACE(bh2, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh2);
+ if (err) goto fail;
+ spin_lock(sb_bgl_lock(sbi, group));
+ gdp->bg_free_inodes_count =
+ cpu_to_le16(le16_to_cpu(gdp->bg_free_inodes_count) - 1);
+ if (S_ISDIR(mode)) {
+ gdp->bg_used_dirs_count =
+ cpu_to_le16(le16_to_cpu(gdp->bg_used_dirs_count) + 1);
+ }
+ spin_unlock(sb_bgl_lock(sbi, group));
+ BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bh2);
+ if (err) goto fail;
+
+ percpu_counter_dec(&sbi->s_freeinodes_counter);
+ if (S_ISDIR(mode))
+ percpu_counter_inc(&sbi->s_dirs_counter);
+ sb->s_dirt = 1;
+
+ inode->i_uid = current->fsuid;
+ if (test_opt (sb, GRPID))
+ inode->i_gid = dir->i_gid;
+ else if (dir->i_mode & S_ISGID) {
+ inode->i_gid = dir->i_gid;
+ if (S_ISDIR(mode))
+ mode |= S_ISGID;
+ } else
+ inode->i_gid = current->fsgid;
+ inode->i_mode = mode;
+
+ inode->i_ino = ino;
+ /* This is the optimal IO size (for stat), not the fs block size */
+ inode->i_blocks = 0;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
+
+ memset(ei->i_data, 0, sizeof(ei->i_data));
+ ei->i_dir_start_lookup = 0;
+ ei->i_disksize = 0;
+
+ ei->i_flags = EXT4_I(dir)->i_flags & ~EXT4_INDEX_FL;
+ if (S_ISLNK(mode))
+ ei->i_flags &= ~(EXT4_IMMUTABLE_FL|EXT4_APPEND_FL);
+ /* dirsync only applies to directories */
+ if (!S_ISDIR(mode))
+ ei->i_flags &= ~EXT4_DIRSYNC_FL;
+#ifdef EXT4_FRAGMENTS
+ ei->i_faddr = 0;
+ ei->i_frag_no = 0;
+ ei->i_frag_size = 0;
+#endif
+ ei->i_file_acl = 0;
+ ei->i_dir_acl = 0;
+ ei->i_dtime = 0;
+ ei->i_block_alloc_info = NULL;
+ ei->i_block_group = group;
+
+ ext4_set_inode_flags(inode);
+ if (IS_DIRSYNC(inode))
+ handle->h_sync = 1;
+ insert_inode_hash(inode);
+ spin_lock(&sbi->s_next_gen_lock);
+ inode->i_generation = sbi->s_next_generation++;
+ spin_unlock(&sbi->s_next_gen_lock);
+
+ ei->i_state = EXT4_STATE_NEW;
+ ei->i_extra_isize =
+ (EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) ?
+ sizeof(struct ext4_inode) - EXT4_GOOD_OLD_INODE_SIZE : 0;
+
+ ret = inode;
+ if(DQUOT_ALLOC_INODE(inode)) {
+ err = -EDQUOT;
+ goto fail_drop;
+ }
+
+ err = ext4_init_acl(handle, inode, dir);
+ if (err)
+ goto fail_free_drop;
+
+ err = ext4_init_security(handle,inode, dir);
+ if (err)
+ goto fail_free_drop;
+
+ err = ext4_mark_inode_dirty(handle, inode);
+ if (err) {
+ ext4_std_error(sb, err);
+ goto fail_free_drop;
+ }
+ if (test_opt(sb, EXTENTS)) {
+ EXT4_I(inode)->i_flags |= EXT4_EXTENTS_FL;
+ ext4_ext_tree_init(handle, inode);
+ if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+ err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
+ if (err) goto fail;
+ EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS);
+ BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
+ }
+ }
+
+ ext4_debug("allocating inode %lu\n", inode->i_ino);
+ goto really_out;
+fail:
+ ext4_std_error(sb, err);
+out:
+ iput(inode);
+ ret = ERR_PTR(err);
+really_out:
+ brelse(bitmap_bh);
+ return ret;
+
+fail_free_drop:
+ DQUOT_FREE_INODE(inode);
+
+fail_drop:
+ DQUOT_DROP(inode);
+ inode->i_flags |= S_NOQUOTA;
+ inode->i_nlink = 0;
+ iput(inode);
+ brelse(bitmap_bh);
+ return ERR_PTR(err);
+}
+
+/* Verify that we are loading a valid orphan from disk */
+struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
+{
+ unsigned long max_ino = le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count);
+ unsigned long block_group;
+ int bit;
+ struct buffer_head *bitmap_bh = NULL;
+ struct inode *inode = NULL;
+
+ /* Error cases - e2fsck has already cleaned up for us */
+ if (ino > max_ino) {
+ ext4_warning(sb, __FUNCTION__,
+ "bad orphan ino %lu! e2fsck was run?", ino);
+ goto out;
+ }
+
+ block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ bit = (ino - 1) % EXT4_INODES_PER_GROUP(sb);
+ bitmap_bh = read_inode_bitmap(sb, block_group);
+ if (!bitmap_bh) {
+ ext4_warning(sb, __FUNCTION__,
+ "inode bitmap error for orphan %lu", ino);
+ goto out;
+ }
+
+ /* Having the inode bit set should be a 100% indicator that this
+ * is a valid orphan (no e2fsck run on fs). Orphans also include
+ * inodes that were being truncated, so we can't check i_nlink==0.
+ */
+ if (!ext4_test_bit(bit, bitmap_bh->b_data) ||
+ !(inode = iget(sb, ino)) || is_bad_inode(inode) ||
+ NEXT_ORPHAN(inode) > max_ino) {
+ ext4_warning(sb, __FUNCTION__,
+ "bad orphan inode %lu! e2fsck was run?", ino);
+ printk(KERN_NOTICE "ext4_test_bit(bit=%d, block=%llu) = %d\n",
+ bit, (unsigned long long)bitmap_bh->b_blocknr,
+ ext4_test_bit(bit, bitmap_bh->b_data));
+ printk(KERN_NOTICE "inode=%p\n", inode);
+ if (inode) {
+ printk(KERN_NOTICE "is_bad_inode(inode)=%d\n",
+ is_bad_inode(inode));
+ printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
+ NEXT_ORPHAN(inode));
+ printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
+ }
+ /* Avoid freeing blocks if we got a bad deleted inode */
+ if (inode && inode->i_nlink == 0)
+ inode->i_blocks = 0;
+ iput(inode);
+ inode = NULL;
+ }
+out:
+ brelse(bitmap_bh);
+ return inode;
+}
+
+unsigned long ext4_count_free_inodes (struct super_block * sb)
+{
+ unsigned long desc_count;
+ struct ext4_group_desc *gdp;
+ int i;
+#ifdef EXT4FS_DEBUG
+ struct ext4_super_block *es;
+ unsigned long bitmap_count, x;
+ struct buffer_head *bitmap_bh = NULL;
+
+ es = EXT4_SB(sb)->s_es;
+ desc_count = 0;
+ bitmap_count = 0;
+ gdp = NULL;
+ for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
+ gdp = ext4_get_group_desc (sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
+ brelse(bitmap_bh);
+ bitmap_bh = read_inode_bitmap(sb, i);
+ if (!bitmap_bh)
+ continue;
+
+ x = ext4_count_free(bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8);
+ printk("group %d: stored = %d, counted = %lu\n",
+ i, le16_to_cpu(gdp->bg_free_inodes_count), x);
+ bitmap_count += x;
+ }
+ brelse(bitmap_bh);
+ printk("ext4_count_free_inodes: stored = %u, computed = %lu, %lu\n",
+ le32_to_cpu(es->s_free_inodes_count), desc_count, bitmap_count);
+ return desc_count;
+#else
+ desc_count = 0;
+ for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
+ gdp = ext4_get_group_desc (sb, i, NULL);
+ if (!gdp)
+ continue;
+ desc_count += le16_to_cpu(gdp->bg_free_inodes_count);
+ cond_resched();
+ }
+ return desc_count;
+#endif
+}
+
+/* Called at mount-time, super-block is locked */
+unsigned long ext4_count_dirs (struct super_block * sb)
+{
+ unsigned long count = 0;
+ int i;
+
+ for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) {
+ struct ext4_group_desc *gdp = ext4_get_group_desc (sb, i, NULL);
+ if (!gdp)
+ continue;
+ count += le16_to_cpu(gdp->bg_used_dirs_count);
+ }
+ return count;
+}
+
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
new file mode 100644
index 000000000000..0a60ec5a16db
--- /dev/null
+++ b/fs/ext4/inode.c
@@ -0,0 +1,3233 @@
+/*
+ * linux/fs/ext4/inode.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/inode.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Goal-directed block allocation by Stephen Tweedie
+ * (sct@redhat.com), 1993, 1998
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ * 64-bit file support on 64-bit platforms by Jakub Jelinek
+ * (jj@sunsite.ms.mff.cuni.cz)
+ *
+ * Assorted race fixes, rewrite of ext4_get_block() by Al Viro, 2000
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/jbd2.h>
+#include <linux/smp_lock.h>
+#include <linux/highuid.h>
+#include <linux/pagemap.h>
+#include <linux/quotaops.h>
+#include <linux/string.h>
+#include <linux/buffer_head.h>
+#include <linux/writeback.h>
+#include <linux/mpage.h>
+#include <linux/uio.h>
+#include <linux/bio.h>
+#include "xattr.h"
+#include "acl.h"
+
+/*
+ * Test whether an inode is a fast symlink.
+ */
+static int ext4_inode_is_fast_symlink(struct inode *inode)
+{
+ int ea_blocks = EXT4_I(inode)->i_file_acl ?
+ (inode->i_sb->s_blocksize >> 9) : 0;
+
+ return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0);
+}
+
+/*
+ * The ext4 forget function must perform a revoke if we are freeing data
+ * which has been journaled. Metadata (eg. indirect blocks) must be
+ * revoked in all cases.
+ *
+ * "bh" may be NULL: a metadata block may have been freed from memory
+ * but there may still be a record of it in the journal, and that record
+ * still needs to be revoked.
+ */
+int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
+ struct buffer_head *bh, ext4_fsblk_t blocknr)
+{
+ int err;
+
+ might_sleep();
+
+ BUFFER_TRACE(bh, "enter");
+
+ jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
+ "data mode %lx\n",
+ bh, is_metadata, inode->i_mode,
+ test_opt(inode->i_sb, DATA_FLAGS));
+
+ /* Never use the revoke function if we are doing full data
+ * journaling: there is no need to, and a V1 superblock won't
+ * support it. Otherwise, only skip the revoke on un-journaled
+ * data blocks. */
+
+ if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
+ (!is_metadata && !ext4_should_journal_data(inode))) {
+ if (bh) {
+ BUFFER_TRACE(bh, "call jbd2_journal_forget");
+ return ext4_journal_forget(handle, bh);
+ }
+ return 0;
+ }
+
+ /*
+ * data!=journal && (is_metadata || should_journal_data(inode))
+ */
+ BUFFER_TRACE(bh, "call ext4_journal_revoke");
+ err = ext4_journal_revoke(handle, blocknr, bh);
+ if (err)
+ ext4_abort(inode->i_sb, __FUNCTION__,
+ "error %d when attempting revoke", err);
+ BUFFER_TRACE(bh, "exit");
+ return err;
+}
+
+/*
+ * Work out how many blocks we need to proceed with the next chunk of a
+ * truncate transaction.
+ */
+static unsigned long blocks_for_truncate(struct inode *inode)
+{
+ unsigned long needed;
+
+ needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9);
+
+ /* Give ourselves just enough room to cope with inodes in which
+ * i_blocks is corrupt: we've seen disk corruptions in the past
+ * which resulted in random data in an inode which looked enough
+ * like a regular file for ext4 to try to delete it. Things
+ * will go a bit crazy if that happens, but at least we should
+ * try not to panic the whole kernel. */
+ if (needed < 2)
+ needed = 2;
+
+ /* But we need to bound the transaction so we don't overflow the
+ * journal. */
+ if (needed > EXT4_MAX_TRANS_DATA)
+ needed = EXT4_MAX_TRANS_DATA;
+
+ return EXT4_DATA_TRANS_BLOCKS(inode->i_sb) + needed;
+}
+
+/*
+ * Truncate transactions can be complex and absolutely huge. So we need to
+ * be able to restart the transaction at a conventient checkpoint to make
+ * sure we don't overflow the journal.
+ *
+ * start_transaction gets us a new handle for a truncate transaction,
+ * and extend_transaction tries to extend the existing one a bit. If
+ * extend fails, we need to propagate the failure up and restart the
+ * transaction in the top-level truncate loop. --sct
+ */
+static handle_t *start_transaction(struct inode *inode)
+{
+ handle_t *result;
+
+ result = ext4_journal_start(inode, blocks_for_truncate(inode));
+ if (!IS_ERR(result))
+ return result;
+
+ ext4_std_error(inode->i_sb, PTR_ERR(result));
+ return result;
+}
+
+/*
+ * Try to extend this transaction for the purposes of truncation.
+ *
+ * Returns 0 if we managed to create more room. If we can't create more
+ * room, and the transaction must be restarted we return 1.
+ */
+static int try_to_extend_transaction(handle_t *handle, struct inode *inode)
+{
+ if (handle->h_buffer_credits > EXT4_RESERVE_TRANS_BLOCKS)
+ return 0;
+ if (!ext4_journal_extend(handle, blocks_for_truncate(inode)))
+ return 0;
+ return 1;
+}
+
+/*
+ * Restart the transaction associated with *handle. This does a commit,
+ * so before we call here everything must be consistently dirtied against
+ * this transaction.
+ */
+static int ext4_journal_test_restart(handle_t *handle, struct inode *inode)
+{
+ jbd_debug(2, "restarting handle %p\n", handle);
+ return ext4_journal_restart(handle, blocks_for_truncate(inode));
+}
+
+/*
+ * Called at the last iput() if i_nlink is zero.
+ */
+void ext4_delete_inode (struct inode * inode)
+{
+ handle_t *handle;
+
+ truncate_inode_pages(&inode->i_data, 0);
+
+ if (is_bad_inode(inode))
+ goto no_delete;
+
+ handle = start_transaction(inode);
+ if (IS_ERR(handle)) {
+ /*
+ * If we're going to skip the normal cleanup, we still need to
+ * make sure that the in-core orphan linked list is properly
+ * cleaned up.
+ */
+ ext4_orphan_del(NULL, inode);
+ goto no_delete;
+ }
+
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+ inode->i_size = 0;
+ if (inode->i_blocks)
+ ext4_truncate(inode);
+ /*
+ * Kill off the orphan record which ext4_truncate created.
+ * AKPM: I think this can be inside the above `if'.
+ * Note that ext4_orphan_del() has to be able to cope with the
+ * deletion of a non-existent orphan - this is because we don't
+ * know if ext4_truncate() actually created an orphan record.
+ * (Well, we could do this if we need to, but heck - it works)
+ */
+ ext4_orphan_del(handle, inode);
+ EXT4_I(inode)->i_dtime = get_seconds();
+
+ /*
+ * One subtle ordering requirement: if anything has gone wrong
+ * (transaction abort, IO errors, whatever), then we can still
+ * do these next steps (the fs will already have been marked as
+ * having errors), but we can't free the inode if the mark_dirty
+ * fails.
+ */
+ if (ext4_mark_inode_dirty(handle, inode))
+ /* If that failed, just do the required in-core inode clear. */
+ clear_inode(inode);
+ else
+ ext4_free_inode(handle, inode);
+ ext4_journal_stop(handle);
+ return;
+no_delete:
+ clear_inode(inode); /* We must guarantee clearing of inode... */
+}
+
+typedef struct {
+ __le32 *p;
+ __le32 key;
+ struct buffer_head *bh;
+} Indirect;
+
+static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v)
+{
+ p->key = *(p->p = v);
+ p->bh = bh;
+}
+
+static int verify_chain(Indirect *from, Indirect *to)
+{
+ while (from <= to && from->key == *from->p)
+ from++;
+ return (from > to);
+}
+
+/**
+ * ext4_block_to_path - parse the block number into array of offsets
+ * @inode: inode in question (we are only interested in its superblock)
+ * @i_block: block number to be parsed
+ * @offsets: array to store the offsets in
+ * @boundary: set this non-zero if the referred-to block is likely to be
+ * followed (on disk) by an indirect block.
+ *
+ * To store the locations of file's data ext4 uses a data structure common
+ * for UNIX filesystems - tree of pointers anchored in the inode, with
+ * data blocks at leaves and indirect blocks in intermediate nodes.
+ * This function translates the block number into path in that tree -
+ * return value is the path length and @offsets[n] is the offset of
+ * pointer to (n+1)th node in the nth one. If @block is out of range
+ * (negative or too large) warning is printed and zero returned.
+ *
+ * Note: function doesn't find node addresses, so no IO is needed. All
+ * we need to know is the capacity of indirect blocks (taken from the
+ * inode->i_sb).
+ */
+
+/*
+ * Portability note: the last comparison (check that we fit into triple
+ * indirect block) is spelled differently, because otherwise on an
+ * architecture with 32-bit longs and 8Kb pages we might get into trouble
+ * if our filesystem had 8Kb blocks. We might use long long, but that would
+ * kill us on x86. Oh, well, at least the sign propagation does not matter -
+ * i_block would have to be negative in the very beginning, so we would not
+ * get there at all.
+ */
+
+static int ext4_block_to_path(struct inode *inode,
+ long i_block, int offsets[4], int *boundary)
+{
+ int ptrs = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ int ptrs_bits = EXT4_ADDR_PER_BLOCK_BITS(inode->i_sb);
+ const long direct_blocks = EXT4_NDIR_BLOCKS,
+ indirect_blocks = ptrs,
+ double_blocks = (1 << (ptrs_bits * 2));
+ int n = 0;
+ int final = 0;
+
+ if (i_block < 0) {
+ ext4_warning (inode->i_sb, "ext4_block_to_path", "block < 0");
+ } else if (i_block < direct_blocks) {
+ offsets[n++] = i_block;
+ final = direct_blocks;
+ } else if ( (i_block -= direct_blocks) < indirect_blocks) {
+ offsets[n++] = EXT4_IND_BLOCK;
+ offsets[n++] = i_block;
+ final = ptrs;
+ } else if ((i_block -= indirect_blocks) < double_blocks) {
+ offsets[n++] = EXT4_DIND_BLOCK;
+ offsets[n++] = i_block >> ptrs_bits;
+ offsets[n++] = i_block & (ptrs - 1);
+ final = ptrs;
+ } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) {
+ offsets[n++] = EXT4_TIND_BLOCK;
+ offsets[n++] = i_block >> (ptrs_bits * 2);
+ offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1);
+ offsets[n++] = i_block & (ptrs - 1);
+ final = ptrs;
+ } else {
+ ext4_warning(inode->i_sb, "ext4_block_to_path", "block > big");
+ }
+ if (boundary)
+ *boundary = final - 1 - (i_block & (ptrs - 1));
+ return n;
+}
+
+/**
+ * ext4_get_branch - read the chain of indirect blocks leading to data
+ * @inode: inode in question
+ * @depth: depth of the chain (1 - direct pointer, etc.)
+ * @offsets: offsets of pointers in inode/indirect blocks
+ * @chain: place to store the result
+ * @err: here we store the error value
+ *
+ * Function fills the array of triples <key, p, bh> and returns %NULL
+ * if everything went OK or the pointer to the last filled triple
+ * (incomplete one) otherwise. Upon the return chain[i].key contains
+ * the number of (i+1)-th block in the chain (as it is stored in memory,
+ * i.e. little-endian 32-bit), chain[i].p contains the address of that
+ * number (it points into struct inode for i==0 and into the bh->b_data
+ * for i>0) and chain[i].bh points to the buffer_head of i-th indirect
+ * block for i>0 and NULL for i==0. In other words, it holds the block
+ * numbers of the chain, addresses they were taken from (and where we can
+ * verify that chain did not change) and buffer_heads hosting these
+ * numbers.
+ *
+ * Function stops when it stumbles upon zero pointer (absent block)
+ * (pointer to last triple returned, *@err == 0)
+ * or when it gets an IO error reading an indirect block
+ * (ditto, *@err == -EIO)
+ * or when it notices that chain had been changed while it was reading
+ * (ditto, *@err == -EAGAIN)
+ * or when it reads all @depth-1 indirect blocks successfully and finds
+ * the whole chain, all way to the data (returns %NULL, *err == 0).
+ */
+static Indirect *ext4_get_branch(struct inode *inode, int depth, int *offsets,
+ Indirect chain[4], int *err)
+{
+ struct super_block *sb = inode->i_sb;
+ Indirect *p = chain;
+ struct buffer_head *bh;
+
+ *err = 0;
+ /* i_data is not going away, no lock needed */
+ add_chain (chain, NULL, EXT4_I(inode)->i_data + *offsets);
+ if (!p->key)
+ goto no_block;
+ while (--depth) {
+ bh = sb_bread(sb, le32_to_cpu(p->key));
+ if (!bh)
+ goto failure;
+ /* Reader: pointers */
+ if (!verify_chain(chain, p))
+ goto changed;
+ add_chain(++p, bh, (__le32*)bh->b_data + *++offsets);
+ /* Reader: end */
+ if (!p->key)
+ goto no_block;
+ }
+ return NULL;
+
+changed:
+ brelse(bh);
+ *err = -EAGAIN;
+ goto no_block;
+failure:
+ *err = -EIO;
+no_block:
+ return p;
+}
+
+/**
+ * ext4_find_near - find a place for allocation with sufficient locality
+ * @inode: owner
+ * @ind: descriptor of indirect block.
+ *
+ * This function returns the prefered place for block allocation.
+ * It is used when heuristic for sequential allocation fails.
+ * Rules are:
+ * + if there is a block to the left of our position - allocate near it.
+ * + if pointer will live in indirect block - allocate near that block.
+ * + if pointer will live in inode - allocate in the same
+ * cylinder group.
+ *
+ * In the latter case we colour the starting block by the callers PID to
+ * prevent it from clashing with concurrent allocations for a different inode
+ * in the same block group. The PID is used here so that functionally related
+ * files will be close-by on-disk.
+ *
+ * Caller must make sure that @ind is valid and will stay that way.
+ */
+static ext4_fsblk_t ext4_find_near(struct inode *inode, Indirect *ind)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data;
+ __le32 *p;
+ ext4_fsblk_t bg_start;
+ ext4_grpblk_t colour;
+
+ /* Try to find previous block */
+ for (p = ind->p - 1; p >= start; p--) {
+ if (*p)
+ return le32_to_cpu(*p);
+ }
+
+ /* No such thing, so let's try location of indirect block */
+ if (ind->bh)
+ return ind->bh->b_blocknr;
+
+ /*
+ * It is going to be referred to from the inode itself? OK, just put it
+ * into the same cylinder group then.
+ */
+ bg_start = ext4_group_first_block_no(inode->i_sb, ei->i_block_group);
+ colour = (current->pid % 16) *
+ (EXT4_BLOCKS_PER_GROUP(inode->i_sb) / 16);
+ return bg_start + colour;
+}
+
+/**
+ * ext4_find_goal - find a prefered place for allocation.
+ * @inode: owner
+ * @block: block we want
+ * @chain: chain of indirect blocks
+ * @partial: pointer to the last triple within a chain
+ * @goal: place to store the result.
+ *
+ * Normally this function find the prefered place for block allocation,
+ * stores it in *@goal and returns zero.
+ */
+
+static ext4_fsblk_t ext4_find_goal(struct inode *inode, long block,
+ Indirect chain[4], Indirect *partial)
+{
+ struct ext4_block_alloc_info *block_i;
+
+ block_i = EXT4_I(inode)->i_block_alloc_info;
+
+ /*
+ * try the heuristic for sequential allocation,
+ * failing that at least try to get decent locality.
+ */
+ if (block_i && (block == block_i->last_alloc_logical_block + 1)
+ && (block_i->last_alloc_physical_block != 0)) {
+ return block_i->last_alloc_physical_block + 1;
+ }
+
+ return ext4_find_near(inode, partial);
+}
+
+/**
+ * ext4_blks_to_allocate: Look up the block map and count the number
+ * of direct blocks need to be allocated for the given branch.
+ *
+ * @branch: chain of indirect blocks
+ * @k: number of blocks need for indirect blocks
+ * @blks: number of data blocks to be mapped.
+ * @blocks_to_boundary: the offset in the indirect block
+ *
+ * return the total number of blocks to be allocate, including the
+ * direct and indirect blocks.
+ */
+static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned long blks,
+ int blocks_to_boundary)
+{
+ unsigned long count = 0;
+
+ /*
+ * Simple case, [t,d]Indirect block(s) has not allocated yet
+ * then it's clear blocks on that path have not allocated
+ */
+ if (k > 0) {
+ /* right now we don't handle cross boundary allocation */
+ if (blks < blocks_to_boundary + 1)
+ count += blks;
+ else
+ count += blocks_to_boundary + 1;
+ return count;
+ }
+
+ count++;
+ while (count < blks && count <= blocks_to_boundary &&
+ le32_to_cpu(*(branch[0].p + count)) == 0) {
+ count++;
+ }
+ return count;
+}
+
+/**
+ * ext4_alloc_blocks: multiple allocate blocks needed for a branch
+ * @indirect_blks: the number of blocks need to allocate for indirect
+ * blocks
+ *
+ * @new_blocks: on return it will store the new block numbers for
+ * the indirect blocks(if needed) and the first direct block,
+ * @blks: on return it will store the total number of allocated
+ * direct blocks
+ */
+static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
+ ext4_fsblk_t goal, int indirect_blks, int blks,
+ ext4_fsblk_t new_blocks[4], int *err)
+{
+ int target, i;
+ unsigned long count = 0;
+ int index = 0;
+ ext4_fsblk_t current_block = 0;
+ int ret = 0;
+
+ /*
+ * Here we try to allocate the requested multiple blocks at once,
+ * on a best-effort basis.
+ * To build a branch, we should allocate blocks for
+ * the indirect blocks(if not allocated yet), and at least
+ * the first direct block of this branch. That's the
+ * minimum number of blocks need to allocate(required)
+ */
+ target = blks + indirect_blks;
+
+ while (1) {
+ count = target;
+ /* allocating blocks for indirect blocks and direct blocks */
+ current_block = ext4_new_blocks(handle,inode,goal,&count,err);
+ if (*err)
+ goto failed_out;
+
+ target -= count;
+ /* allocate blocks for indirect blocks */
+ while (index < indirect_blks && count) {
+ new_blocks[index++] = current_block++;
+ count--;
+ }
+
+ if (count > 0)
+ break;
+ }
+
+ /* save the new block number for the first direct block */
+ new_blocks[index] = current_block;
+
+ /* total number of blocks allocated for direct blocks */
+ ret = count;
+ *err = 0;
+ return ret;
+failed_out:
+ for (i = 0; i <index; i++)
+ ext4_free_blocks(handle, inode, new_blocks[i], 1);
+ return ret;
+}
+
+/**
+ * ext4_alloc_branch - allocate and set up a chain of blocks.
+ * @inode: owner
+ * @indirect_blks: number of allocated indirect blocks
+ * @blks: number of allocated direct blocks
+ * @offsets: offsets (in the blocks) to store the pointers to next.
+ * @branch: place to store the chain in.
+ *
+ * This function allocates blocks, zeroes out all but the last one,
+ * links them into chain and (if we are synchronous) writes them to disk.
+ * In other words, it prepares a branch that can be spliced onto the
+ * inode. It stores the information about that chain in the branch[], in
+ * the same format as ext4_get_branch() would do. We are calling it after
+ * we had read the existing part of chain and partial points to the last
+ * triple of that (one with zero ->key). Upon the exit we have the same
+ * picture as after the successful ext4_get_block(), except that in one
+ * place chain is disconnected - *branch->p is still zero (we did not
+ * set the last link), but branch->key contains the number that should
+ * be placed into *branch->p to fill that gap.
+ *
+ * If allocation fails we free all blocks we've allocated (and forget
+ * their buffer_heads) and return the error value the from failed
+ * ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain
+ * as described above and return 0.
+ */
+static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
+ int indirect_blks, int *blks, ext4_fsblk_t goal,
+ int *offsets, Indirect *branch)
+{
+ int blocksize = inode->i_sb->s_blocksize;
+ int i, n = 0;
+ int err = 0;
+ struct buffer_head *bh;
+ int num;
+ ext4_fsblk_t new_blocks[4];
+ ext4_fsblk_t current_block;
+
+ num = ext4_alloc_blocks(handle, inode, goal, indirect_blks,
+ *blks, new_blocks, &err);
+ if (err)
+ return err;
+
+ branch[0].key = cpu_to_le32(new_blocks[0]);
+ /*
+ * metadata blocks and data blocks are allocated.
+ */
+ for (n = 1; n <= indirect_blks; n++) {
+ /*
+ * Get buffer_head for parent block, zero it out
+ * and set the pointer to new one, then send
+ * parent to disk.
+ */
+ bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
+ branch[n].bh = bh;
+ lock_buffer(bh);
+ BUFFER_TRACE(bh, "call get_create_access");
+ err = ext4_journal_get_create_access(handle, bh);
+ if (err) {
+ unlock_buffer(bh);
+ brelse(bh);
+ goto failed;
+ }
+
+ memset(bh->b_data, 0, blocksize);
+ branch[n].p = (__le32 *) bh->b_data + offsets[n];
+ branch[n].key = cpu_to_le32(new_blocks[n]);
+ *branch[n].p = branch[n].key;
+ if ( n == indirect_blks) {
+ current_block = new_blocks[n];
+ /*
+ * End of chain, update the last new metablock of
+ * the chain to point to the new allocated
+ * data blocks numbers
+ */
+ for (i=1; i < num; i++)
+ *(branch[n].p + i) = cpu_to_le32(++current_block);
+ }
+ BUFFER_TRACE(bh, "marking uptodate");
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bh);
+ if (err)
+ goto failed;
+ }
+ *blks = num;
+ return err;
+failed:
+ /* Allocation failed, free what we already allocated */
+ for (i = 1; i <= n ; i++) {
+ BUFFER_TRACE(branch[i].bh, "call jbd2_journal_forget");
+ ext4_journal_forget(handle, branch[i].bh);
+ }
+ for (i = 0; i <indirect_blks; i++)
+ ext4_free_blocks(handle, inode, new_blocks[i], 1);
+
+ ext4_free_blocks(handle, inode, new_blocks[i], num);
+
+ return err;
+}
+
+/**
+ * ext4_splice_branch - splice the allocated branch onto inode.
+ * @inode: owner
+ * @block: (logical) number of block we are adding
+ * @chain: chain of indirect blocks (with a missing link - see
+ * ext4_alloc_branch)
+ * @where: location of missing link
+ * @num: number of indirect blocks we are adding
+ * @blks: number of direct blocks we are adding
+ *
+ * This function fills the missing link and does all housekeeping needed in
+ * inode (->i_blocks, etc.). In case of success we end up with the full
+ * chain to new block and return 0.
+ */
+static int ext4_splice_branch(handle_t *handle, struct inode *inode,
+ long block, Indirect *where, int num, int blks)
+{
+ int i;
+ int err = 0;
+ struct ext4_block_alloc_info *block_i;
+ ext4_fsblk_t current_block;
+
+ block_i = EXT4_I(inode)->i_block_alloc_info;
+ /*
+ * If we're splicing into a [td]indirect block (as opposed to the
+ * inode) then we need to get write access to the [td]indirect block
+ * before the splice.
+ */
+ if (where->bh) {
+ BUFFER_TRACE(where->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, where->bh);
+ if (err)
+ goto err_out;
+ }
+ /* That's it */
+
+ *where->p = where->key;
+
+ /*
+ * Update the host buffer_head or inode to point to more just allocated
+ * direct blocks blocks
+ */
+ if (num == 0 && blks > 1) {
+ current_block = le32_to_cpu(where->key) + 1;
+ for (i = 1; i < blks; i++)
+ *(where->p + i ) = cpu_to_le32(current_block++);
+ }
+
+ /*
+ * update the most recently allocated logical & physical block
+ * in i_block_alloc_info, to assist find the proper goal block for next
+ * allocation
+ */
+ if (block_i) {
+ block_i->last_alloc_logical_block = block + blks - 1;
+ block_i->last_alloc_physical_block =
+ le32_to_cpu(where[num].key) + blks - 1;
+ }
+
+ /* We are done with atomic stuff, now do the rest of housekeeping */
+
+ inode->i_ctime = CURRENT_TIME_SEC;
+ ext4_mark_inode_dirty(handle, inode);
+
+ /* had we spliced it onto indirect block? */
+ if (where->bh) {
+ /*
+ * If we spliced it onto an indirect block, we haven't
+ * altered the inode. Note however that if it is being spliced
+ * onto an indirect block at the very end of the file (the
+ * file is growing) then we *will* alter the inode to reflect
+ * the new i_size. But that is not done here - it is done in
+ * generic_commit_write->__mark_inode_dirty->ext4_dirty_inode.
+ */
+ jbd_debug(5, "splicing indirect only\n");
+ BUFFER_TRACE(where->bh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, where->bh);
+ if (err)
+ goto err_out;
+ } else {
+ /*
+ * OK, we spliced it into the inode itself on a direct block.
+ * Inode was dirtied above.
+ */
+ jbd_debug(5, "splicing direct\n");
+ }
+ return err;
+
+err_out:
+ for (i = 1; i <= num; i++) {
+ BUFFER_TRACE(where[i].bh, "call jbd2_journal_forget");
+ ext4_journal_forget(handle, where[i].bh);
+ ext4_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1);
+ }
+ ext4_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks);
+
+ return err;
+}
+
+/*
+ * Allocation strategy is simple: if we have to allocate something, we will
+ * have to go the whole way to leaf. So let's do it before attaching anything
+ * to tree, set linkage between the newborn blocks, write them if sync is
+ * required, recheck the path, free and repeat if check fails, otherwise
+ * set the last missing link (that will protect us from any truncate-generated
+ * removals - all blocks on the path are immune now) and possibly force the
+ * write on the parent block.
+ * That has a nice additional property: no special recovery from the failed
+ * allocations is needed - we simply release blocks and do not touch anything
+ * reachable from inode.
+ *
+ * `handle' can be NULL if create == 0.
+ *
+ * The BKL may not be held on entry here. Be sure to take it early.
+ * return > 0, # of blocks mapped or allocated.
+ * return = 0, if plain lookup failed.
+ * return < 0, error case.
+ */
+int ext4_get_blocks_handle(handle_t *handle, struct inode *inode,
+ sector_t iblock, unsigned long maxblocks,
+ struct buffer_head *bh_result,
+ int create, int extend_disksize)
+{
+ int err = -EIO;
+ int offsets[4];
+ Indirect chain[4];
+ Indirect *partial;
+ ext4_fsblk_t goal;
+ int indirect_blks;
+ int blocks_to_boundary = 0;
+ int depth;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ int count = 0;
+ ext4_fsblk_t first_block = 0;
+
+
+ J_ASSERT(!(EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL));
+ J_ASSERT(handle != NULL || create == 0);
+ depth = ext4_block_to_path(inode,iblock,offsets,&blocks_to_boundary);
+
+ if (depth == 0)
+ goto out;
+
+ partial = ext4_get_branch(inode, depth, offsets, chain, &err);
+
+ /* Simplest case - block found, no allocation needed */
+ if (!partial) {
+ first_block = le32_to_cpu(chain[depth - 1].key);
+ clear_buffer_new(bh_result);
+ count++;
+ /*map more blocks*/
+ while (count < maxblocks && count <= blocks_to_boundary) {
+ ext4_fsblk_t blk;
+
+ if (!verify_chain(chain, partial)) {
+ /*
+ * Indirect block might be removed by
+ * truncate while we were reading it.
+ * Handling of that case: forget what we've
+ * got now. Flag the err as EAGAIN, so it
+ * will reread.
+ */
+ err = -EAGAIN;
+ count = 0;
+ break;
+ }
+ blk = le32_to_cpu(*(chain[depth-1].p + count));
+
+ if (blk == first_block + count)
+ count++;
+ else
+ break;
+ }
+ if (err != -EAGAIN)
+ goto got_it;
+ }
+
+ /* Next simple case - plain lookup or failed read of indirect block */
+ if (!create || err == -EIO)
+ goto cleanup;
+
+ mutex_lock(&ei->truncate_mutex);
+
+ /*
+ * If the indirect block is missing while we are reading
+ * the chain(ext4_get_branch() returns -EAGAIN err), or
+ * if the chain has been changed after we grab the semaphore,
+ * (either because another process truncated this branch, or
+ * another get_block allocated this branch) re-grab the chain to see if
+ * the request block has been allocated or not.
+ *
+ * Since we already block the truncate/other get_block
+ * at this point, we will have the current copy of the chain when we
+ * splice the branch into the tree.
+ */
+ if (err == -EAGAIN || !verify_chain(chain, partial)) {
+ while (partial > chain) {
+ brelse(partial->bh);
+ partial--;
+ }
+ partial = ext4_get_branch(inode, depth, offsets, chain, &err);
+ if (!partial) {
+ count++;
+ mutex_unlock(&ei->truncate_mutex);
+ if (err)
+ goto cleanup;
+ clear_buffer_new(bh_result);
+ goto got_it;
+ }
+ }
+
+ /*
+ * Okay, we need to do block allocation. Lazily initialize the block
+ * allocation info here if necessary
+ */
+ if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info))
+ ext4_init_block_alloc_info(inode);
+
+ goal = ext4_find_goal(inode, iblock, chain, partial);
+
+ /* the number of blocks need to allocate for [d,t]indirect blocks */
+ indirect_blks = (chain + depth) - partial - 1;
+
+ /*
+ * Next look up the indirect map to count the totoal number of
+ * direct blocks to allocate for this branch.
+ */
+ count = ext4_blks_to_allocate(partial, indirect_blks,
+ maxblocks, blocks_to_boundary);
+ /*
+ * Block out ext4_truncate while we alter the tree
+ */
+ err = ext4_alloc_branch(handle, inode, indirect_blks, &count, goal,
+ offsets + (partial - chain), partial);
+
+ /*
+ * The ext4_splice_branch call will free and forget any buffers
+ * on the new chain if there is a failure, but that risks using
+ * up transaction credits, especially for bitmaps where the
+ * credits cannot be returned. Can we handle this somehow? We
+ * may need to return -EAGAIN upwards in the worst case. --sct
+ */
+ if (!err)
+ err = ext4_splice_branch(handle, inode, iblock,
+ partial, indirect_blks, count);
+ /*
+ * i_disksize growing is protected by truncate_mutex. Don't forget to
+ * protect it if you're about to implement concurrent
+ * ext4_get_block() -bzzz
+ */
+ if (!err && extend_disksize && inode->i_size > ei->i_disksize)
+ ei->i_disksize = inode->i_size;
+ mutex_unlock(&ei->truncate_mutex);
+ if (err)
+ goto cleanup;
+
+ set_buffer_new(bh_result);
+got_it:
+ map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key));
+ if (count > blocks_to_boundary)
+ set_buffer_boundary(bh_result);
+ err = count;
+ /* Clean up and exit */
+ partial = chain + depth - 1; /* the whole chain */
+cleanup:
+ while (partial > chain) {
+ BUFFER_TRACE(partial->bh, "call brelse");
+ brelse(partial->bh);
+ partial--;
+ }
+ BUFFER_TRACE(bh_result, "returned");
+out:
+ return err;
+}
+
+#define DIO_CREDITS (EXT4_RESERVE_TRANS_BLOCKS + 32)
+
+static int ext4_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ handle_t *handle = journal_current_handle();
+ int ret = 0;
+ unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+
+ if (!create)
+ goto get_block; /* A read */
+
+ if (max_blocks == 1)
+ goto get_block; /* A single block get */
+
+ if (handle->h_transaction->t_state == T_LOCKED) {
+ /*
+ * Huge direct-io writes can hold off commits for long
+ * periods of time. Let this commit run.
+ */
+ ext4_journal_stop(handle);
+ handle = ext4_journal_start(inode, DIO_CREDITS);
+ if (IS_ERR(handle))
+ ret = PTR_ERR(handle);
+ goto get_block;
+ }
+
+ if (handle->h_buffer_credits <= EXT4_RESERVE_TRANS_BLOCKS) {
+ /*
+ * Getting low on buffer credits...
+ */
+ ret = ext4_journal_extend(handle, DIO_CREDITS);
+ if (ret > 0) {
+ /*
+ * Couldn't extend the transaction. Start a new one.
+ */
+ ret = ext4_journal_restart(handle, DIO_CREDITS);
+ }
+ }
+
+get_block:
+ if (ret == 0) {
+ ret = ext4_get_blocks_wrap(handle, inode, iblock,
+ max_blocks, bh_result, create, 0);
+ if (ret > 0) {
+ bh_result->b_size = (ret << inode->i_blkbits);
+ ret = 0;
+ }
+ }
+ return ret;
+}
+
+/*
+ * `handle' can be NULL if create is zero
+ */
+struct buffer_head *ext4_getblk(handle_t *handle, struct inode *inode,
+ long block, int create, int *errp)
+{
+ struct buffer_head dummy;
+ int fatal = 0, err;
+
+ J_ASSERT(handle != NULL || create == 0);
+
+ dummy.b_state = 0;
+ dummy.b_blocknr = -1000;
+ buffer_trace_init(&dummy.b_history);
+ err = ext4_get_blocks_wrap(handle, inode, block, 1,
+ &dummy, create, 1);
+ /*
+ * ext4_get_blocks_handle() returns number of blocks
+ * mapped. 0 in case of a HOLE.
+ */
+ if (err > 0) {
+ if (err > 1)
+ WARN_ON(1);
+ err = 0;
+ }
+ *errp = err;
+ if (!err && buffer_mapped(&dummy)) {
+ struct buffer_head *bh;
+ bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
+ if (!bh) {
+ *errp = -EIO;
+ goto err;
+ }
+ if (buffer_new(&dummy)) {
+ J_ASSERT(create != 0);
+ J_ASSERT(handle != 0);
+
+ /*
+ * Now that we do not always journal data, we should
+ * keep in mind whether this should always journal the
+ * new buffer as metadata. For now, regular file
+ * writes use ext4_get_block instead, so it's not a
+ * problem.
+ */
+ lock_buffer(bh);
+ BUFFER_TRACE(bh, "call get_create_access");
+ fatal = ext4_journal_get_create_access(handle, bh);
+ if (!fatal && !buffer_uptodate(bh)) {
+ memset(bh->b_data,0,inode->i_sb->s_blocksize);
+ set_buffer_uptodate(bh);
+ }
+ unlock_buffer(bh);
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bh);
+ if (!fatal)
+ fatal = err;
+ } else {
+ BUFFER_TRACE(bh, "not a new buffer");
+ }
+ if (fatal) {
+ *errp = fatal;
+ brelse(bh);
+ bh = NULL;
+ }
+ return bh;
+ }
+err:
+ return NULL;
+}
+
+struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
+ int block, int create, int *err)
+{
+ struct buffer_head * bh;
+
+ bh = ext4_getblk(handle, inode, block, create, err);
+ if (!bh)
+ return bh;
+ if (buffer_uptodate(bh))
+ return bh;
+ ll_rw_block(READ_META, 1, &bh);
+ wait_on_buffer(bh);
+ if (buffer_uptodate(bh))
+ return bh;
+ put_bh(bh);
+ *err = -EIO;
+ return NULL;
+}
+
+static int walk_page_buffers( handle_t *handle,
+ struct buffer_head *head,
+ unsigned from,
+ unsigned to,
+ int *partial,
+ int (*fn)( handle_t *handle,
+ struct buffer_head *bh))
+{
+ struct buffer_head *bh;
+ unsigned block_start, block_end;
+ unsigned blocksize = head->b_size;
+ int err, ret = 0;
+ struct buffer_head *next;
+
+ for ( bh = head, block_start = 0;
+ ret == 0 && (bh != head || !block_start);
+ block_start = block_end, bh = next)
+ {
+ next = bh->b_this_page;
+ block_end = block_start + blocksize;
+ if (block_end <= from || block_start >= to) {
+ if (partial && !buffer_uptodate(bh))
+ *partial = 1;
+ continue;
+ }
+ err = (*fn)(handle, bh);
+ if (!ret)
+ ret = err;
+ }
+ return ret;
+}
+
+/*
+ * To preserve ordering, it is essential that the hole instantiation and
+ * the data write be encapsulated in a single transaction. We cannot
+ * close off a transaction and start a new one between the ext4_get_block()
+ * and the commit_write(). So doing the jbd2_journal_start at the start of
+ * prepare_write() is the right place.
+ *
+ * Also, this function can nest inside ext4_writepage() ->
+ * block_write_full_page(). In that case, we *know* that ext4_writepage()
+ * has generated enough buffer credits to do the whole page. So we won't
+ * block on the journal in that case, which is good, because the caller may
+ * be PF_MEMALLOC.
+ *
+ * By accident, ext4 can be reentered when a transaction is open via
+ * quota file writes. If we were to commit the transaction while thus
+ * reentered, there can be a deadlock - we would be holding a quota
+ * lock, and the commit would never complete if another thread had a
+ * transaction open and was blocking on the quota lock - a ranking
+ * violation.
+ *
+ * So what we do is to rely on the fact that jbd2_journal_stop/journal_start
+ * will _not_ run commit under these circumstances because handle->h_ref
+ * is elevated. We'll still have enough credits for the tiny quotafile
+ * write.
+ */
+static int do_journal_get_write_access(handle_t *handle,
+ struct buffer_head *bh)
+{
+ if (!buffer_mapped(bh) || buffer_freed(bh))
+ return 0;
+ return ext4_journal_get_write_access(handle, bh);
+}
+
+static int ext4_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct inode *inode = page->mapping->host;
+ int ret, needed_blocks = ext4_writepage_trans_blocks(inode);
+ handle_t *handle;
+ int retries = 0;
+
+retry:
+ handle = ext4_journal_start(inode, needed_blocks);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+ if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
+ ret = nobh_prepare_write(page, from, to, ext4_get_block);
+ else
+ ret = block_prepare_write(page, from, to, ext4_get_block);
+ if (ret)
+ goto prepare_write_failed;
+
+ if (ext4_should_journal_data(inode)) {
+ ret = walk_page_buffers(handle, page_buffers(page),
+ from, to, NULL, do_journal_get_write_access);
+ }
+prepare_write_failed:
+ if (ret)
+ ext4_journal_stop(handle);
+ if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+out:
+ return ret;
+}
+
+int ext4_journal_dirty_data(handle_t *handle, struct buffer_head *bh)
+{
+ int err = jbd2_journal_dirty_data(handle, bh);
+ if (err)
+ ext4_journal_abort_handle(__FUNCTION__, __FUNCTION__,
+ bh, handle,err);
+ return err;
+}
+
+/* For commit_write() in data=journal mode */
+static int commit_write_fn(handle_t *handle, struct buffer_head *bh)
+{
+ if (!buffer_mapped(bh) || buffer_freed(bh))
+ return 0;
+ set_buffer_uptodate(bh);
+ return ext4_journal_dirty_metadata(handle, bh);
+}
+
+/*
+ * We need to pick up the new inode size which generic_commit_write gave us
+ * `file' can be NULL - eg, when called from page_symlink().
+ *
+ * ext4 never places buffers on inode->i_mapping->private_list. metadata
+ * buffers are managed internally.
+ */
+static int ext4_ordered_commit_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ handle_t *handle = ext4_journal_current_handle();
+ struct inode *inode = page->mapping->host;
+ int ret = 0, ret2;
+
+ ret = walk_page_buffers(handle, page_buffers(page),
+ from, to, NULL, ext4_journal_dirty_data);
+
+ if (ret == 0) {
+ /*
+ * generic_commit_write() will run mark_inode_dirty() if i_size
+ * changes. So let's piggyback the i_disksize mark_inode_dirty
+ * into that.
+ */
+ loff_t new_i_size;
+
+ new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+ if (new_i_size > EXT4_I(inode)->i_disksize)
+ EXT4_I(inode)->i_disksize = new_i_size;
+ ret = generic_commit_write(file, page, from, to);
+ }
+ ret2 = ext4_journal_stop(handle);
+ if (!ret)
+ ret = ret2;
+ return ret;
+}
+
+static int ext4_writeback_commit_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ handle_t *handle = ext4_journal_current_handle();
+ struct inode *inode = page->mapping->host;
+ int ret = 0, ret2;
+ loff_t new_i_size;
+
+ new_i_size = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+ if (new_i_size > EXT4_I(inode)->i_disksize)
+ EXT4_I(inode)->i_disksize = new_i_size;
+
+ if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
+ ret = nobh_commit_write(file, page, from, to);
+ else
+ ret = generic_commit_write(file, page, from, to);
+
+ ret2 = ext4_journal_stop(handle);
+ if (!ret)
+ ret = ret2;
+ return ret;
+}
+
+static int ext4_journalled_commit_write(struct file *file,
+ struct page *page, unsigned from, unsigned to)
+{
+ handle_t *handle = ext4_journal_current_handle();
+ struct inode *inode = page->mapping->host;
+ int ret = 0, ret2;
+ int partial = 0;
+ loff_t pos;
+
+ /*
+ * Here we duplicate the generic_commit_write() functionality
+ */
+ pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+
+ ret = walk_page_buffers(handle, page_buffers(page), from,
+ to, &partial, commit_write_fn);
+ if (!partial)
+ SetPageUptodate(page);
+ if (pos > inode->i_size)
+ i_size_write(inode, pos);
+ EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
+ if (inode->i_size > EXT4_I(inode)->i_disksize) {
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ ret2 = ext4_mark_inode_dirty(handle, inode);
+ if (!ret)
+ ret = ret2;
+ }
+ ret2 = ext4_journal_stop(handle);
+ if (!ret)
+ ret = ret2;
+ return ret;
+}
+
+/*
+ * bmap() is special. It gets used by applications such as lilo and by
+ * the swapper to find the on-disk block of a specific piece of data.
+ *
+ * Naturally, this is dangerous if the block concerned is still in the
+ * journal. If somebody makes a swapfile on an ext4 data-journaling
+ * filesystem and enables swap, then they may get a nasty shock when the
+ * data getting swapped to that swapfile suddenly gets overwritten by
+ * the original zero's written out previously to the journal and
+ * awaiting writeback in the kernel's buffer cache.
+ *
+ * So, if we see any bmap calls here on a modified, data-journaled file,
+ * take extra steps to flush any blocks which might be in the cache.
+ */
+static sector_t ext4_bmap(struct address_space *mapping, sector_t block)
+{
+ struct inode *inode = mapping->host;
+ journal_t *journal;
+ int err;
+
+ if (EXT4_I(inode)->i_state & EXT4_STATE_JDATA) {
+ /*
+ * This is a REALLY heavyweight approach, but the use of
+ * bmap on dirty files is expected to be extremely rare:
+ * only if we run lilo or swapon on a freshly made file
+ * do we expect this to happen.
+ *
+ * (bmap requires CAP_SYS_RAWIO so this does not
+ * represent an unprivileged user DOS attack --- we'd be
+ * in trouble if mortal users could trigger this path at
+ * will.)
+ *
+ * NB. EXT4_STATE_JDATA is not set on files other than
+ * regular files. If somebody wants to bmap a directory
+ * or symlink and gets confused because the buffer
+ * hasn't yet been flushed to disk, they deserve
+ * everything they get.
+ */
+
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_JDATA;
+ journal = EXT4_JOURNAL(inode);
+ jbd2_journal_lock_updates(journal);
+ err = jbd2_journal_flush(journal);
+ jbd2_journal_unlock_updates(journal);
+
+ if (err)
+ return 0;
+ }
+
+ return generic_block_bmap(mapping,block,ext4_get_block);
+}
+
+static int bget_one(handle_t *handle, struct buffer_head *bh)
+{
+ get_bh(bh);
+ return 0;
+}
+
+static int bput_one(handle_t *handle, struct buffer_head *bh)
+{
+ put_bh(bh);
+ return 0;
+}
+
+static int jbd2_journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh)
+{
+ if (buffer_mapped(bh))
+ return ext4_journal_dirty_data(handle, bh);
+ return 0;
+}
+
+/*
+ * Note that we always start a transaction even if we're not journalling
+ * data. This is to preserve ordering: any hole instantiation within
+ * __block_write_full_page -> ext4_get_block() should be journalled
+ * along with the data so we don't crash and then get metadata which
+ * refers to old data.
+ *
+ * In all journalling modes block_write_full_page() will start the I/O.
+ *
+ * Problem:
+ *
+ * ext4_writepage() -> kmalloc() -> __alloc_pages() -> page_launder() ->
+ * ext4_writepage()
+ *
+ * Similar for:
+ *
+ * ext4_file_write() -> generic_file_write() -> __alloc_pages() -> ...
+ *
+ * Same applies to ext4_get_block(). We will deadlock on various things like
+ * lock_journal and i_truncate_mutex.
+ *
+ * Setting PF_MEMALLOC here doesn't work - too many internal memory
+ * allocations fail.
+ *
+ * 16May01: If we're reentered then journal_current_handle() will be
+ * non-zero. We simply *return*.
+ *
+ * 1 July 2001: @@@ FIXME:
+ * In journalled data mode, a data buffer may be metadata against the
+ * current transaction. But the same file is part of a shared mapping
+ * and someone does a writepage() on it.
+ *
+ * We will move the buffer onto the async_data list, but *after* it has
+ * been dirtied. So there's a small window where we have dirty data on
+ * BJ_Metadata.
+ *
+ * Note that this only applies to the last partial page in the file. The
+ * bit which block_write_full_page() uses prepare/commit for. (That's
+ * broken code anyway: it's wrong for msync()).
+ *
+ * It's a rare case: affects the final partial page, for journalled data
+ * where the file is subject to bith write() and writepage() in the same
+ * transction. To fix it we'll need a custom block_write_full_page().
+ * We'll probably need that anyway for journalling writepage() output.
+ *
+ * We don't honour synchronous mounts for writepage(). That would be
+ * disastrous. Any write() or metadata operation will sync the fs for
+ * us.
+ *
+ * AKPM2: if all the page's buffers are mapped to disk and !data=journal,
+ * we don't need to open a transaction here.
+ */
+static int ext4_ordered_writepage(struct page *page,
+ struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ struct buffer_head *page_bufs;
+ handle_t *handle = NULL;
+ int ret = 0;
+ int err;
+
+ J_ASSERT(PageLocked(page));
+
+ /*
+ * We give up here if we're reentered, because it might be for a
+ * different filesystem.
+ */
+ if (ext4_journal_current_handle())
+ goto out_fail;
+
+ handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out_fail;
+ }
+
+ if (!page_has_buffers(page)) {
+ create_empty_buffers(page, inode->i_sb->s_blocksize,
+ (1 << BH_Dirty)|(1 << BH_Uptodate));
+ }
+ page_bufs = page_buffers(page);
+ walk_page_buffers(handle, page_bufs, 0,
+ PAGE_CACHE_SIZE, NULL, bget_one);
+
+ ret = block_write_full_page(page, ext4_get_block, wbc);
+
+ /*
+ * The page can become unlocked at any point now, and
+ * truncate can then come in and change things. So we
+ * can't touch *page from now on. But *page_bufs is
+ * safe due to elevated refcount.
+ */
+
+ /*
+ * And attach them to the current transaction. But only if
+ * block_write_full_page() succeeded. Otherwise they are unmapped,
+ * and generally junk.
+ */
+ if (ret == 0) {
+ err = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE,
+ NULL, jbd2_journal_dirty_data_fn);
+ if (!ret)
+ ret = err;
+ }
+ walk_page_buffers(handle, page_bufs, 0,
+ PAGE_CACHE_SIZE, NULL, bput_one);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+
+out_fail:
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return ret;
+}
+
+static int ext4_writeback_writepage(struct page *page,
+ struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ handle_t *handle = NULL;
+ int ret = 0;
+ int err;
+
+ if (ext4_journal_current_handle())
+ goto out_fail;
+
+ handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out_fail;
+ }
+
+ if (test_opt(inode->i_sb, NOBH) && ext4_should_writeback_data(inode))
+ ret = nobh_writepage(page, ext4_get_block, wbc);
+ else
+ ret = block_write_full_page(page, ext4_get_block, wbc);
+
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+
+out_fail:
+ redirty_page_for_writepage(wbc, page);
+ unlock_page(page);
+ return ret;
+}
+
+static int ext4_journalled_writepage(struct page *page,
+ struct writeback_control *wbc)
+{
+ struct inode *inode = page->mapping->host;
+ handle_t *handle = NULL;
+ int ret = 0;
+ int err;
+
+ if (ext4_journal_current_handle())
+ goto no_write;
+
+ handle = ext4_journal_start(inode, ext4_writepage_trans_blocks(inode));
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto no_write;
+ }
+
+ if (!page_has_buffers(page) || PageChecked(page)) {
+ /*
+ * It's mmapped pagecache. Add buffers and journal it. There
+ * doesn't seem much point in redirtying the page here.
+ */
+ ClearPageChecked(page);
+ ret = block_prepare_write(page, 0, PAGE_CACHE_SIZE,
+ ext4_get_block);
+ if (ret != 0) {
+ ext4_journal_stop(handle);
+ goto out_unlock;
+ }
+ ret = walk_page_buffers(handle, page_buffers(page), 0,
+ PAGE_CACHE_SIZE, NULL, do_journal_get_write_access);
+
+ err = walk_page_buffers(handle, page_buffers(page), 0,
+ PAGE_CACHE_SIZE, NULL, commit_write_fn);
+ if (ret == 0)
+ ret = err;
+ EXT4_I(inode)->i_state |= EXT4_STATE_JDATA;
+ unlock_page(page);
+ } else {
+ /*
+ * It may be a page full of checkpoint-mode buffers. We don't
+ * really know unless we go poke around in the buffer_heads.
+ * But block_write_full_page will do the right thing.
+ */
+ ret = block_write_full_page(page, ext4_get_block, wbc);
+ }
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+out:
+ return ret;
+
+no_write:
+ redirty_page_for_writepage(wbc, page);
+out_unlock:
+ unlock_page(page);
+ goto out;
+}
+
+static int ext4_readpage(struct file *file, struct page *page)
+{
+ return mpage_readpage(page, ext4_get_block);
+}
+
+static int
+ext4_readpages(struct file *file, struct address_space *mapping,
+ struct list_head *pages, unsigned nr_pages)
+{
+ return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
+}
+
+static void ext4_invalidatepage(struct page *page, unsigned long offset)
+{
+ journal_t *journal = EXT4_JOURNAL(page->mapping->host);
+
+ /*
+ * If it's a full truncate we just forget about the pending dirtying
+ */
+ if (offset == 0)
+ ClearPageChecked(page);
+
+ jbd2_journal_invalidatepage(journal, page, offset);
+}
+
+static int ext4_releasepage(struct page *page, gfp_t wait)
+{
+ journal_t *journal = EXT4_JOURNAL(page->mapping->host);
+
+ WARN_ON(PageChecked(page));
+ if (!page_has_buffers(page))
+ return 0;
+ return jbd2_journal_try_to_free_buffers(journal, page, wait);
+}
+
+/*
+ * If the O_DIRECT write will extend the file then add this inode to the
+ * orphan list. So recovery will truncate it back to the original size
+ * if the machine crashes during the write.
+ *
+ * If the O_DIRECT write is intantiating holes inside i_size and the machine
+ * crashes then stale disk data _may_ be exposed inside the file.
+ */
+static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
+ const struct iovec *iov, loff_t offset,
+ unsigned long nr_segs)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file->f_mapping->host;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ handle_t *handle = NULL;
+ ssize_t ret;
+ int orphan = 0;
+ size_t count = iov_length(iov, nr_segs);
+
+ if (rw == WRITE) {
+ loff_t final_size = offset + count;
+
+ handle = ext4_journal_start(inode, DIO_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ goto out;
+ }
+ if (final_size > inode->i_size) {
+ ret = ext4_orphan_add(handle, inode);
+ if (ret)
+ goto out_stop;
+ orphan = 1;
+ ei->i_disksize = inode->i_size;
+ }
+ }
+
+ ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
+ offset, nr_segs,
+ ext4_get_block, NULL);
+
+ /*
+ * Reacquire the handle: ext4_get_block() can restart the transaction
+ */
+ handle = journal_current_handle();
+
+out_stop:
+ if (handle) {
+ int err;
+
+ if (orphan && inode->i_nlink)
+ ext4_orphan_del(handle, inode);
+ if (orphan && ret > 0) {
+ loff_t end = offset + ret;
+ if (end > inode->i_size) {
+ ei->i_disksize = end;
+ i_size_write(inode, end);
+ /*
+ * We're going to return a positive `ret'
+ * here due to non-zero-length I/O, so there's
+ * no way of reporting error returns from
+ * ext4_mark_inode_dirty() to userspace. So
+ * ignore it.
+ */
+ ext4_mark_inode_dirty(handle, inode);
+ }
+ }
+ err = ext4_journal_stop(handle);
+ if (ret == 0)
+ ret = err;
+ }
+out:
+ return ret;
+}
+
+/*
+ * Pages can be marked dirty completely asynchronously from ext4's journalling
+ * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do
+ * much here because ->set_page_dirty is called under VFS locks. The page is
+ * not necessarily locked.
+ *
+ * We cannot just dirty the page and leave attached buffers clean, because the
+ * buffers' dirty state is "definitive". We cannot just set the buffers dirty
+ * or jbddirty because all the journalling code will explode.
+ *
+ * So what we do is to mark the page "pending dirty" and next time writepage
+ * is called, propagate that into the buffers appropriately.
+ */
+static int ext4_journalled_set_page_dirty(struct page *page)
+{
+ SetPageChecked(page);
+ return __set_page_dirty_nobuffers(page);
+}
+
+static const struct address_space_operations ext4_ordered_aops = {
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_ordered_writepage,
+ .sync_page = block_sync_page,
+ .prepare_write = ext4_prepare_write,
+ .commit_write = ext4_ordered_commit_write,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+};
+
+static const struct address_space_operations ext4_writeback_aops = {
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_writeback_writepage,
+ .sync_page = block_sync_page,
+ .prepare_write = ext4_prepare_write,
+ .commit_write = ext4_writeback_commit_write,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+ .direct_IO = ext4_direct_IO,
+ .migratepage = buffer_migrate_page,
+};
+
+static const struct address_space_operations ext4_journalled_aops = {
+ .readpage = ext4_readpage,
+ .readpages = ext4_readpages,
+ .writepage = ext4_journalled_writepage,
+ .sync_page = block_sync_page,
+ .prepare_write = ext4_prepare_write,
+ .commit_write = ext4_journalled_commit_write,
+ .set_page_dirty = ext4_journalled_set_page_dirty,
+ .bmap = ext4_bmap,
+ .invalidatepage = ext4_invalidatepage,
+ .releasepage = ext4_releasepage,
+};
+
+void ext4_set_aops(struct inode *inode)
+{
+ if (ext4_should_order_data(inode))
+ inode->i_mapping->a_ops = &ext4_ordered_aops;
+ else if (ext4_should_writeback_data(inode))
+ inode->i_mapping->a_ops = &ext4_writeback_aops;
+ else
+ inode->i_mapping->a_ops = &ext4_journalled_aops;
+}
+
+/*
+ * ext4_block_truncate_page() zeroes out a mapping from file offset `from'
+ * up to the end of the block which corresponds to `from'.
+ * This required during truncate. We need to physically zero the tail end
+ * of that block so it doesn't yield old data if the file is later grown.
+ */
+int ext4_block_truncate_page(handle_t *handle, struct page *page,
+ struct address_space *mapping, loff_t from)
+{
+ ext4_fsblk_t index = from >> PAGE_CACHE_SHIFT;
+ unsigned offset = from & (PAGE_CACHE_SIZE-1);
+ unsigned blocksize, iblock, length, pos;
+ struct inode *inode = mapping->host;
+ struct buffer_head *bh;
+ int err = 0;
+ void *kaddr;
+
+ blocksize = inode->i_sb->s_blocksize;
+ length = blocksize - (offset & (blocksize - 1));
+ iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits);
+
+ /*
+ * For "nobh" option, we can only work if we don't need to
+ * read-in the page - otherwise we create buffers to do the IO.
+ */
+ if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
+ ext4_should_writeback_data(inode) && PageUptodate(page)) {
+ kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr + offset, 0, length);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+ set_page_dirty(page);
+ goto unlock;
+ }
+
+ if (!page_has_buffers(page))
+ create_empty_buffers(page, blocksize, 0);
+
+ /* Find the buffer that contains "offset" */
+ bh = page_buffers(page);
+ pos = blocksize;
+ while (offset >= pos) {
+ bh = bh->b_this_page;
+ iblock++;
+ pos += blocksize;
+ }
+
+ err = 0;
+ if (buffer_freed(bh)) {
+ BUFFER_TRACE(bh, "freed: skip");
+ goto unlock;
+ }
+
+ if (!buffer_mapped(bh)) {
+ BUFFER_TRACE(bh, "unmapped");
+ ext4_get_block(inode, iblock, bh, 0);
+ /* unmapped? It's a hole - nothing to do */
+ if (!buffer_mapped(bh)) {
+ BUFFER_TRACE(bh, "still unmapped");
+ goto unlock;
+ }
+ }
+
+ /* Ok, it's mapped. Make sure it's up-to-date */
+ if (PageUptodate(page))
+ set_buffer_uptodate(bh);
+
+ if (!buffer_uptodate(bh)) {
+ err = -EIO;
+ ll_rw_block(READ, 1, &bh);
+ wait_on_buffer(bh);
+ /* Uhhuh. Read error. Complain and punt. */
+ if (!buffer_uptodate(bh))
+ goto unlock;
+ }
+
+ if (ext4_should_journal_data(inode)) {
+ BUFFER_TRACE(bh, "get write access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err)
+ goto unlock;
+ }
+
+ kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr + offset, 0, length);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+
+ BUFFER_TRACE(bh, "zeroed end of block");
+
+ err = 0;
+ if (ext4_should_journal_data(inode)) {
+ err = ext4_journal_dirty_metadata(handle, bh);
+ } else {
+ if (ext4_should_order_data(inode))
+ err = ext4_journal_dirty_data(handle, bh);
+ mark_buffer_dirty(bh);
+ }
+
+unlock:
+ unlock_page(page);
+ page_cache_release(page);
+ return err;
+}
+
+/*
+ * Probably it should be a library function... search for first non-zero word
+ * or memcmp with zero_page, whatever is better for particular architecture.
+ * Linus?
+ */
+static inline int all_zeroes(__le32 *p, __le32 *q)
+{
+ while (p < q)
+ if (*p++)
+ return 0;
+ return 1;
+}
+
+/**
+ * ext4_find_shared - find the indirect blocks for partial truncation.
+ * @inode: inode in question
+ * @depth: depth of the affected branch
+ * @offsets: offsets of pointers in that branch (see ext4_block_to_path)
+ * @chain: place to store the pointers to partial indirect blocks
+ * @top: place to the (detached) top of branch
+ *
+ * This is a helper function used by ext4_truncate().
+ *
+ * When we do truncate() we may have to clean the ends of several
+ * indirect blocks but leave the blocks themselves alive. Block is
+ * partially truncated if some data below the new i_size is refered
+ * from it (and it is on the path to the first completely truncated
+ * data block, indeed). We have to free the top of that path along
+ * with everything to the right of the path. Since no allocation
+ * past the truncation point is possible until ext4_truncate()
+ * finishes, we may safely do the latter, but top of branch may
+ * require special attention - pageout below the truncation point
+ * might try to populate it.
+ *
+ * We atomically detach the top of branch from the tree, store the
+ * block number of its root in *@top, pointers to buffer_heads of
+ * partially truncated blocks - in @chain[].bh and pointers to
+ * their last elements that should not be removed - in
+ * @chain[].p. Return value is the pointer to last filled element
+ * of @chain.
+ *
+ * The work left to caller to do the actual freeing of subtrees:
+ * a) free the subtree starting from *@top
+ * b) free the subtrees whose roots are stored in
+ * (@chain[i].p+1 .. end of @chain[i].bh->b_data)
+ * c) free the subtrees growing from the inode past the @chain[0].
+ * (no partially truncated stuff there). */
+
+static Indirect *ext4_find_shared(struct inode *inode, int depth,
+ int offsets[4], Indirect chain[4], __le32 *top)
+{
+ Indirect *partial, *p;
+ int k, err;
+
+ *top = 0;
+ /* Make k index the deepest non-null offest + 1 */
+ for (k = depth; k > 1 && !offsets[k-1]; k--)
+ ;
+ partial = ext4_get_branch(inode, k, offsets, chain, &err);
+ /* Writer: pointers */
+ if (!partial)
+ partial = chain + k-1;
+ /*
+ * If the branch acquired continuation since we've looked at it -
+ * fine, it should all survive and (new) top doesn't belong to us.
+ */
+ if (!partial->key && *partial->p)
+ /* Writer: end */
+ goto no_top;
+ for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--)
+ ;
+ /*
+ * OK, we've found the last block that must survive. The rest of our
+ * branch should be detached before unlocking. However, if that rest
+ * of branch is all ours and does not grow immediately from the inode
+ * it's easier to cheat and just decrement partial->p.
+ */
+ if (p == chain + k - 1 && p > chain) {
+ p->p--;
+ } else {
+ *top = *p->p;
+ /* Nope, don't do this in ext4. Must leave the tree intact */
+#if 0
+ *p->p = 0;
+#endif
+ }
+ /* Writer: end */
+
+ while(partial > p) {
+ brelse(partial->bh);
+ partial--;
+ }
+no_top:
+ return partial;
+}
+
+/*
+ * Zero a number of block pointers in either an inode or an indirect block.
+ * If we restart the transaction we must again get write access to the
+ * indirect block for further modification.
+ *
+ * We release `count' blocks on disk, but (last - first) may be greater
+ * than `count' because there can be holes in there.
+ */
+static void ext4_clear_blocks(handle_t *handle, struct inode *inode,
+ struct buffer_head *bh, ext4_fsblk_t block_to_free,
+ unsigned long count, __le32 *first, __le32 *last)
+{
+ __le32 *p;
+ if (try_to_extend_transaction(handle, inode)) {
+ if (bh) {
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, bh);
+ }
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_journal_test_restart(handle, inode);
+ if (bh) {
+ BUFFER_TRACE(bh, "retaking write access");
+ ext4_journal_get_write_access(handle, bh);
+ }
+ }
+
+ /*
+ * Any buffers which are on the journal will be in memory. We find
+ * them on the hash table so jbd2_journal_revoke() will run jbd2_journal_forget()
+ * on them. We've already detached each block from the file, so
+ * bforget() in jbd2_journal_forget() should be safe.
+ *
+ * AKPM: turn on bforget in jbd2_journal_forget()!!!
+ */
+ for (p = first; p < last; p++) {
+ u32 nr = le32_to_cpu(*p);
+ if (nr) {
+ struct buffer_head *bh;
+
+ *p = 0;
+ bh = sb_find_get_block(inode->i_sb, nr);
+ ext4_forget(handle, 0, inode, bh, nr);
+ }
+ }
+
+ ext4_free_blocks(handle, inode, block_to_free, count);
+}
+
+/**
+ * ext4_free_data - free a list of data blocks
+ * @handle: handle for this transaction
+ * @inode: inode we are dealing with
+ * @this_bh: indirect buffer_head which contains *@first and *@last
+ * @first: array of block numbers
+ * @last: points immediately past the end of array
+ *
+ * We are freeing all blocks refered from that array (numbers are stored as
+ * little-endian 32-bit) and updating @inode->i_blocks appropriately.
+ *
+ * We accumulate contiguous runs of blocks to free. Conveniently, if these
+ * blocks are contiguous then releasing them at one time will only affect one
+ * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't
+ * actually use a lot of journal space.
+ *
+ * @this_bh will be %NULL if @first and @last point into the inode's direct
+ * block pointers.
+ */
+static void ext4_free_data(handle_t *handle, struct inode *inode,
+ struct buffer_head *this_bh,
+ __le32 *first, __le32 *last)
+{
+ ext4_fsblk_t block_to_free = 0; /* Starting block # of a run */
+ unsigned long count = 0; /* Number of blocks in the run */
+ __le32 *block_to_free_p = NULL; /* Pointer into inode/ind
+ corresponding to
+ block_to_free */
+ ext4_fsblk_t nr; /* Current block # */
+ __le32 *p; /* Pointer into inode/ind
+ for current block */
+ int err;
+
+ if (this_bh) { /* For indirect block */
+ BUFFER_TRACE(this_bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, this_bh);
+ /* Important: if we can't update the indirect pointers
+ * to the blocks, we can't free them. */
+ if (err)
+ return;
+ }
+
+ for (p = first; p < last; p++) {
+ nr = le32_to_cpu(*p);
+ if (nr) {
+ /* accumulate blocks to free if they're contiguous */
+ if (count == 0) {
+ block_to_free = nr;
+ block_to_free_p = p;
+ count = 1;
+ } else if (nr == block_to_free + count) {
+ count++;
+ } else {
+ ext4_clear_blocks(handle, inode, this_bh,
+ block_to_free,
+ count, block_to_free_p, p);
+ block_to_free = nr;
+ block_to_free_p = p;
+ count = 1;
+ }
+ }
+ }
+
+ if (count > 0)
+ ext4_clear_blocks(handle, inode, this_bh, block_to_free,
+ count, block_to_free_p, p);
+
+ if (this_bh) {
+ BUFFER_TRACE(this_bh, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, this_bh);
+ }
+}
+
+/**
+ * ext4_free_branches - free an array of branches
+ * @handle: JBD handle for this transaction
+ * @inode: inode we are dealing with
+ * @parent_bh: the buffer_head which contains *@first and *@last
+ * @first: array of block numbers
+ * @last: pointer immediately past the end of array
+ * @depth: depth of the branches to free
+ *
+ * We are freeing all blocks refered from these branches (numbers are
+ * stored as little-endian 32-bit) and updating @inode->i_blocks
+ * appropriately.
+ */
+static void ext4_free_branches(handle_t *handle, struct inode *inode,
+ struct buffer_head *parent_bh,
+ __le32 *first, __le32 *last, int depth)
+{
+ ext4_fsblk_t nr;
+ __le32 *p;
+
+ if (is_handle_aborted(handle))
+ return;
+
+ if (depth--) {
+ struct buffer_head *bh;
+ int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ p = last;
+ while (--p >= first) {
+ nr = le32_to_cpu(*p);
+ if (!nr)
+ continue; /* A hole */
+
+ /* Go read the buffer for the next level down */
+ bh = sb_bread(inode->i_sb, nr);
+
+ /*
+ * A read failure? Report error and clear slot
+ * (should be rare).
+ */
+ if (!bh) {
+ ext4_error(inode->i_sb, "ext4_free_branches",
+ "Read failure, inode=%lu, block=%llu",
+ inode->i_ino, nr);
+ continue;
+ }
+
+ /* This zaps the entire block. Bottom up. */
+ BUFFER_TRACE(bh, "free child branches");
+ ext4_free_branches(handle, inode, bh,
+ (__le32*)bh->b_data,
+ (__le32*)bh->b_data + addr_per_block,
+ depth);
+
+ /*
+ * We've probably journalled the indirect block several
+ * times during the truncate. But it's no longer
+ * needed and we now drop it from the transaction via
+ * jbd2_journal_revoke().
+ *
+ * That's easy if it's exclusively part of this
+ * transaction. But if it's part of the committing
+ * transaction then jbd2_journal_forget() will simply
+ * brelse() it. That means that if the underlying
+ * block is reallocated in ext4_get_block(),
+ * unmap_underlying_metadata() will find this block
+ * and will try to get rid of it. damn, damn.
+ *
+ * If this block has already been committed to the
+ * journal, a revoke record will be written. And
+ * revoke records must be emitted *before* clearing
+ * this block's bit in the bitmaps.
+ */
+ ext4_forget(handle, 1, inode, bh, bh->b_blocknr);
+
+ /*
+ * Everything below this this pointer has been
+ * released. Now let this top-of-subtree go.
+ *
+ * We want the freeing of this indirect block to be
+ * atomic in the journal with the updating of the
+ * bitmap block which owns it. So make some room in
+ * the journal.
+ *
+ * We zero the parent pointer *after* freeing its
+ * pointee in the bitmaps, so if extend_transaction()
+ * for some reason fails to put the bitmap changes and
+ * the release into the same transaction, recovery
+ * will merely complain about releasing a free block,
+ * rather than leaking blocks.
+ */
+ if (is_handle_aborted(handle))
+ return;
+ if (try_to_extend_transaction(handle, inode)) {
+ ext4_mark_inode_dirty(handle, inode);
+ ext4_journal_test_restart(handle, inode);
+ }
+
+ ext4_free_blocks(handle, inode, nr, 1);
+
+ if (parent_bh) {
+ /*
+ * The block which we have just freed is
+ * pointed to by an indirect block: journal it
+ */
+ BUFFER_TRACE(parent_bh, "get_write_access");
+ if (!ext4_journal_get_write_access(handle,
+ parent_bh)){
+ *p = 0;
+ BUFFER_TRACE(parent_bh,
+ "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle,
+ parent_bh);
+ }
+ }
+ }
+ } else {
+ /* We have reached the bottom of the tree. */
+ BUFFER_TRACE(parent_bh, "free data blocks");
+ ext4_free_data(handle, inode, parent_bh, first, last);
+ }
+}
+
+/*
+ * ext4_truncate()
+ *
+ * We block out ext4_get_block() block instantiations across the entire
+ * transaction, and VFS/VM ensures that ext4_truncate() cannot run
+ * simultaneously on behalf of the same inode.
+ *
+ * As we work through the truncate and commmit bits of it to the journal there
+ * is one core, guiding principle: the file's tree must always be consistent on
+ * disk. We must be able to restart the truncate after a crash.
+ *
+ * The file's tree may be transiently inconsistent in memory (although it
+ * probably isn't), but whenever we close off and commit a journal transaction,
+ * the contents of (the filesystem + the journal) must be consistent and
+ * restartable. It's pretty simple, really: bottom up, right to left (although
+ * left-to-right works OK too).
+ *
+ * Note that at recovery time, journal replay occurs *before* the restart of
+ * truncate against the orphan inode list.
+ *
+ * The committed inode has the new, desired i_size (which is the same as
+ * i_disksize in this case). After a crash, ext4_orphan_cleanup() will see
+ * that this inode's truncate did not complete and it will again call
+ * ext4_truncate() to have another go. So there will be instantiated blocks
+ * to the right of the truncation point in a crashed ext4 filesystem. But
+ * that's fine - as long as they are linked from the inode, the post-crash
+ * ext4_truncate() run will find them and release them.
+ */
+void ext4_truncate(struct inode *inode)
+{
+ handle_t *handle;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ __le32 *i_data = ei->i_data;
+ int addr_per_block = EXT4_ADDR_PER_BLOCK(inode->i_sb);
+ struct address_space *mapping = inode->i_mapping;
+ int offsets[4];
+ Indirect chain[4];
+ Indirect *partial;
+ __le32 nr = 0;
+ int n;
+ long last_block;
+ unsigned blocksize = inode->i_sb->s_blocksize;
+ struct page *page;
+
+ if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode)))
+ return;
+ if (ext4_inode_is_fast_symlink(inode))
+ return;
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ return;
+
+ /*
+ * We have to lock the EOF page here, because lock_page() nests
+ * outside jbd2_journal_start().
+ */
+ if ((inode->i_size & (blocksize - 1)) == 0) {
+ /* Block boundary? Nothing to do */
+ page = NULL;
+ } else {
+ page = grab_cache_page(mapping,
+ inode->i_size >> PAGE_CACHE_SHIFT);
+ if (!page)
+ return;
+ }
+
+ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+ return ext4_ext_truncate(inode, page);
+
+ handle = start_transaction(inode);
+ if (IS_ERR(handle)) {
+ if (page) {
+ clear_highpage(page);
+ flush_dcache_page(page);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ return; /* AKPM: return what? */
+ }
+
+ last_block = (inode->i_size + blocksize-1)
+ >> EXT4_BLOCK_SIZE_BITS(inode->i_sb);
+
+ if (page)
+ ext4_block_truncate_page(handle, page, mapping, inode->i_size);
+
+ n = ext4_block_to_path(inode, last_block, offsets, NULL);
+ if (n == 0)
+ goto out_stop; /* error */
+
+ /*
+ * OK. This truncate is going to happen. We add the inode to the
+ * orphan list, so that if this truncate spans multiple transactions,
+ * and we crash, we will resume the truncate when the filesystem
+ * recovers. It also marks the inode dirty, to catch the new size.
+ *
+ * Implication: the file must always be in a sane, consistent
+ * truncatable state while each transaction commits.
+ */
+ if (ext4_orphan_add(handle, inode))
+ goto out_stop;
+
+ /*
+ * The orphan list entry will now protect us from any crash which
+ * occurs before the truncate completes, so it is now safe to propagate
+ * the new, shorter inode size (held for now in i_size) into the
+ * on-disk inode. We do this via i_disksize, which is the value which
+ * ext4 *really* writes onto the disk inode.
+ */
+ ei->i_disksize = inode->i_size;
+
+ /*
+ * From here we block out all ext4_get_block() callers who want to
+ * modify the block allocation tree.
+ */
+ mutex_lock(&ei->truncate_mutex);
+
+ if (n == 1) { /* direct blocks */
+ ext4_free_data(handle, inode, NULL, i_data+offsets[0],
+ i_data + EXT4_NDIR_BLOCKS);
+ goto do_indirects;
+ }
+
+ partial = ext4_find_shared(inode, n, offsets, chain, &nr);
+ /* Kill the top of shared branch (not detached) */
+ if (nr) {
+ if (partial == chain) {
+ /* Shared branch grows from the inode */
+ ext4_free_branches(handle, inode, NULL,
+ &nr, &nr+1, (chain+n-1) - partial);
+ *partial->p = 0;
+ /*
+ * We mark the inode dirty prior to restart,
+ * and prior to stop. No need for it here.
+ */
+ } else {
+ /* Shared branch grows from an indirect block */
+ BUFFER_TRACE(partial->bh, "get_write_access");
+ ext4_free_branches(handle, inode, partial->bh,
+ partial->p,
+ partial->p+1, (chain+n-1) - partial);
+ }
+ }
+ /* Clear the ends of indirect blocks on the shared branch */
+ while (partial > chain) {
+ ext4_free_branches(handle, inode, partial->bh, partial->p + 1,
+ (__le32*)partial->bh->b_data+addr_per_block,
+ (chain+n-1) - partial);
+ BUFFER_TRACE(partial->bh, "call brelse");
+ brelse (partial->bh);
+ partial--;
+ }
+do_indirects:
+ /* Kill the remaining (whole) subtrees */
+ switch (offsets[0]) {
+ default:
+ nr = i_data[EXT4_IND_BLOCK];
+ if (nr) {
+ ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1);
+ i_data[EXT4_IND_BLOCK] = 0;
+ }
+ case EXT4_IND_BLOCK:
+ nr = i_data[EXT4_DIND_BLOCK];
+ if (nr) {
+ ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2);
+ i_data[EXT4_DIND_BLOCK] = 0;
+ }
+ case EXT4_DIND_BLOCK:
+ nr = i_data[EXT4_TIND_BLOCK];
+ if (nr) {
+ ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3);
+ i_data[EXT4_TIND_BLOCK] = 0;
+ }
+ case EXT4_TIND_BLOCK:
+ ;
+ }
+
+ ext4_discard_reservation(inode);
+
+ mutex_unlock(&ei->truncate_mutex);
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
+ ext4_mark_inode_dirty(handle, inode);
+
+ /*
+ * In a multi-transaction truncate, we only make the final transaction
+ * synchronous
+ */
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+out_stop:
+ /*
+ * If this was a simple ftruncate(), and the file will remain alive
+ * then we need to clear up the orphan record which we created above.
+ * However, if this was a real unlink then we were called by
+ * ext4_delete_inode(), and we allow that function to clean up the
+ * orphan info for us.
+ */
+ if (inode->i_nlink)
+ ext4_orphan_del(handle, inode);
+
+ ext4_journal_stop(handle);
+}
+
+static ext4_fsblk_t ext4_get_inode_block(struct super_block *sb,
+ unsigned long ino, struct ext4_iloc *iloc)
+{
+ unsigned long desc, group_desc, block_group;
+ unsigned long offset;
+ ext4_fsblk_t block;
+ struct buffer_head *bh;
+ struct ext4_group_desc * gdp;
+
+ if (!ext4_valid_inum(sb, ino)) {
+ /*
+ * This error is already checked for in namei.c unless we are
+ * looking at an NFS filehandle, in which case no error
+ * report is needed
+ */
+ return 0;
+ }
+
+ block_group = (ino - 1) / EXT4_INODES_PER_GROUP(sb);
+ if (block_group >= EXT4_SB(sb)->s_groups_count) {
+ ext4_error(sb,"ext4_get_inode_block","group >= groups count");
+ return 0;
+ }
+ smp_rmb();
+ group_desc = block_group >> EXT4_DESC_PER_BLOCK_BITS(sb);
+ desc = block_group & (EXT4_DESC_PER_BLOCK(sb) - 1);
+ bh = EXT4_SB(sb)->s_group_desc[group_desc];
+ if (!bh) {
+ ext4_error (sb, "ext4_get_inode_block",
+ "Descriptor not loaded");
+ return 0;
+ }
+
+ gdp = (struct ext4_group_desc *)((__u8 *)bh->b_data +
+ desc * EXT4_DESC_SIZE(sb));
+ /*
+ * Figure out the offset within the block group inode table
+ */
+ offset = ((ino - 1) % EXT4_INODES_PER_GROUP(sb)) *
+ EXT4_INODE_SIZE(sb);
+ block = ext4_inode_table(sb, gdp) +
+ (offset >> EXT4_BLOCK_SIZE_BITS(sb));
+
+ iloc->block_group = block_group;
+ iloc->offset = offset & (EXT4_BLOCK_SIZE(sb) - 1);
+ return block;
+}
+
+/*
+ * ext4_get_inode_loc returns with an extra refcount against the inode's
+ * underlying buffer_head on success. If 'in_mem' is true, we have all
+ * data in memory that is needed to recreate the on-disk version of this
+ * inode.
+ */
+static int __ext4_get_inode_loc(struct inode *inode,
+ struct ext4_iloc *iloc, int in_mem)
+{
+ ext4_fsblk_t block;
+ struct buffer_head *bh;
+
+ block = ext4_get_inode_block(inode->i_sb, inode->i_ino, iloc);
+ if (!block)
+ return -EIO;
+
+ bh = sb_getblk(inode->i_sb, block);
+ if (!bh) {
+ ext4_error (inode->i_sb, "ext4_get_inode_loc",
+ "unable to read inode block - "
+ "inode=%lu, block=%llu",
+ inode->i_ino, block);
+ return -EIO;
+ }
+ if (!buffer_uptodate(bh)) {
+ lock_buffer(bh);
+ if (buffer_uptodate(bh)) {
+ /* someone brought it uptodate while we waited */
+ unlock_buffer(bh);
+ goto has_buffer;
+ }
+
+ /*
+ * If we have all information of the inode in memory and this
+ * is the only valid inode in the block, we need not read the
+ * block.
+ */
+ if (in_mem) {
+ struct buffer_head *bitmap_bh;
+ struct ext4_group_desc *desc;
+ int inodes_per_buffer;
+ int inode_offset, i;
+ int block_group;
+ int start;
+
+ block_group = (inode->i_ino - 1) /
+ EXT4_INODES_PER_GROUP(inode->i_sb);
+ inodes_per_buffer = bh->b_size /
+ EXT4_INODE_SIZE(inode->i_sb);
+ inode_offset = ((inode->i_ino - 1) %
+ EXT4_INODES_PER_GROUP(inode->i_sb));
+ start = inode_offset & ~(inodes_per_buffer - 1);
+
+ /* Is the inode bitmap in cache? */
+ desc = ext4_get_group_desc(inode->i_sb,
+ block_group, NULL);
+ if (!desc)
+ goto make_io;
+
+ bitmap_bh = sb_getblk(inode->i_sb,
+ ext4_inode_bitmap(inode->i_sb, desc));
+ if (!bitmap_bh)
+ goto make_io;
+
+ /*
+ * If the inode bitmap isn't in cache then the
+ * optimisation may end up performing two reads instead
+ * of one, so skip it.
+ */
+ if (!buffer_uptodate(bitmap_bh)) {
+ brelse(bitmap_bh);
+ goto make_io;
+ }
+ for (i = start; i < start + inodes_per_buffer; i++) {
+ if (i == inode_offset)
+ continue;
+ if (ext4_test_bit(i, bitmap_bh->b_data))
+ break;
+ }
+ brelse(bitmap_bh);
+ if (i == start + inodes_per_buffer) {
+ /* all other inodes are free, so skip I/O */
+ memset(bh->b_data, 0, bh->b_size);
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+ goto has_buffer;
+ }
+ }
+
+make_io:
+ /*
+ * There are other valid inodes in the buffer, this inode
+ * has in-inode xattrs, or we don't have this inode in memory.
+ * Read the block from disk.
+ */
+ get_bh(bh);
+ bh->b_end_io = end_buffer_read_sync;
+ submit_bh(READ_META, bh);
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh)) {
+ ext4_error(inode->i_sb, "ext4_get_inode_loc",
+ "unable to read inode block - "
+ "inode=%lu, block=%llu",
+ inode->i_ino, block);
+ brelse(bh);
+ return -EIO;
+ }
+ }
+has_buffer:
+ iloc->bh = bh;
+ return 0;
+}
+
+int ext4_get_inode_loc(struct inode *inode, struct ext4_iloc *iloc)
+{
+ /* We have all inode data except xattrs in memory here. */
+ return __ext4_get_inode_loc(inode, iloc,
+ !(EXT4_I(inode)->i_state & EXT4_STATE_XATTR));
+}
+
+void ext4_set_inode_flags(struct inode *inode)
+{
+ unsigned int flags = EXT4_I(inode)->i_flags;
+
+ inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
+ if (flags & EXT4_SYNC_FL)
+ inode->i_flags |= S_SYNC;
+ if (flags & EXT4_APPEND_FL)
+ inode->i_flags |= S_APPEND;
+ if (flags & EXT4_IMMUTABLE_FL)
+ inode->i_flags |= S_IMMUTABLE;
+ if (flags & EXT4_NOATIME_FL)
+ inode->i_flags |= S_NOATIME;
+ if (flags & EXT4_DIRSYNC_FL)
+ inode->i_flags |= S_DIRSYNC;
+}
+
+void ext4_read_inode(struct inode * inode)
+{
+ struct ext4_iloc iloc;
+ struct ext4_inode *raw_inode;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct buffer_head *bh;
+ int block;
+
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ ei->i_acl = EXT4_ACL_NOT_CACHED;
+ ei->i_default_acl = EXT4_ACL_NOT_CACHED;
+#endif
+ ei->i_block_alloc_info = NULL;
+
+ if (__ext4_get_inode_loc(inode, &iloc, 0))
+ goto bad_inode;
+ bh = iloc.bh;
+ raw_inode = ext4_raw_inode(&iloc);
+ inode->i_mode = le16_to_cpu(raw_inode->i_mode);
+ inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
+ inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+ if(!(test_opt (inode->i_sb, NO_UID32))) {
+ inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
+ inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
+ }
+ inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
+ inode->i_size = le32_to_cpu(raw_inode->i_size);
+ inode->i_atime.tv_sec = le32_to_cpu(raw_inode->i_atime);
+ inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->i_ctime);
+ inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->i_mtime);
+ inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0;
+
+ ei->i_state = 0;
+ ei->i_dir_start_lookup = 0;
+ ei->i_dtime = le32_to_cpu(raw_inode->i_dtime);
+ /* We now have enough fields to check if the inode was active or not.
+ * This is needed because nfsd might try to access dead inodes
+ * the test is that same one that e2fsck uses
+ * NeilBrown 1999oct15
+ */
+ if (inode->i_nlink == 0) {
+ if (inode->i_mode == 0 ||
+ !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
+ /* this inode is deleted */
+ brelse (bh);
+ goto bad_inode;
+ }
+ /* The only unlinked inodes we let through here have
+ * valid i_mode and are being read by the orphan
+ * recovery code: that's fine, we're about to complete
+ * the process of deleting those. */
+ }
+ inode->i_blocks = le32_to_cpu(raw_inode->i_blocks);
+ ei->i_flags = le32_to_cpu(raw_inode->i_flags);
+#ifdef EXT4_FRAGMENTS
+ ei->i_faddr = le32_to_cpu(raw_inode->i_faddr);
+ ei->i_frag_no = raw_inode->i_frag;
+ ei->i_frag_size = raw_inode->i_fsize;
+#endif
+ ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
+ if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
+ cpu_to_le32(EXT4_OS_HURD))
+ ei->i_file_acl |=
+ ((__u64)le16_to_cpu(raw_inode->i_file_acl_high)) << 32;
+ if (!S_ISREG(inode->i_mode)) {
+ ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl);
+ } else {
+ inode->i_size |=
+ ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32;
+ }
+ ei->i_disksize = inode->i_size;
+ inode->i_generation = le32_to_cpu(raw_inode->i_generation);
+ ei->i_block_group = iloc.block_group;
+ /*
+ * NOTE! The in-memory inode i_data array is in little-endian order
+ * even on big-endian machines: we do NOT byteswap the block numbers!
+ */
+ for (block = 0; block < EXT4_N_BLOCKS; block++)
+ ei->i_data[block] = raw_inode->i_block[block];
+ INIT_LIST_HEAD(&ei->i_orphan);
+
+ if (inode->i_ino >= EXT4_FIRST_INO(inode->i_sb) + 1 &&
+ EXT4_INODE_SIZE(inode->i_sb) > EXT4_GOOD_OLD_INODE_SIZE) {
+ /*
+ * When mke2fs creates big inodes it does not zero out
+ * the unused bytes above EXT4_GOOD_OLD_INODE_SIZE,
+ * so ignore those first few inodes.
+ */
+ ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize);
+ if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
+ EXT4_INODE_SIZE(inode->i_sb))
+ goto bad_inode;
+ if (ei->i_extra_isize == 0) {
+ /* The extra space is currently unused. Use it. */
+ ei->i_extra_isize = sizeof(struct ext4_inode) -
+ EXT4_GOOD_OLD_INODE_SIZE;
+ } else {
+ __le32 *magic = (void *)raw_inode +
+ EXT4_GOOD_OLD_INODE_SIZE +
+ ei->i_extra_isize;
+ if (*magic == cpu_to_le32(EXT4_XATTR_MAGIC))
+ ei->i_state |= EXT4_STATE_XATTR;
+ }
+ } else
+ ei->i_extra_isize = 0;
+
+ if (S_ISREG(inode->i_mode)) {
+ inode->i_op = &ext4_file_inode_operations;
+ inode->i_fop = &ext4_file_operations;
+ ext4_set_aops(inode);
+ } else if (S_ISDIR(inode->i_mode)) {
+ inode->i_op = &ext4_dir_inode_operations;
+ inode->i_fop = &ext4_dir_operations;
+ } else if (S_ISLNK(inode->i_mode)) {
+ if (ext4_inode_is_fast_symlink(inode))
+ inode->i_op = &ext4_fast_symlink_inode_operations;
+ else {
+ inode->i_op = &ext4_symlink_inode_operations;
+ ext4_set_aops(inode);
+ }
+ } else {
+ inode->i_op = &ext4_special_inode_operations;
+ if (raw_inode->i_block[0])
+ init_special_inode(inode, inode->i_mode,
+ old_decode_dev(le32_to_cpu(raw_inode->i_block[0])));
+ else
+ init_special_inode(inode, inode->i_mode,
+ new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
+ }
+ brelse (iloc.bh);
+ ext4_set_inode_flags(inode);
+ return;
+
+bad_inode:
+ make_bad_inode(inode);
+ return;
+}
+
+/*
+ * Post the struct inode info into an on-disk inode location in the
+ * buffer-cache. This gobbles the caller's reference to the
+ * buffer_head in the inode location struct.
+ *
+ * The caller must have write access to iloc->bh.
+ */
+static int ext4_do_update_inode(handle_t *handle,
+ struct inode *inode,
+ struct ext4_iloc *iloc)
+{
+ struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct buffer_head *bh = iloc->bh;
+ int err = 0, rc, block;
+
+ /* For fields not not tracking in the in-memory inode,
+ * initialise them to zero for new inodes. */
+ if (ei->i_state & EXT4_STATE_NEW)
+ memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
+
+ raw_inode->i_mode = cpu_to_le16(inode->i_mode);
+ if(!(test_opt(inode->i_sb, NO_UID32))) {
+ raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
+ raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
+/*
+ * Fix up interoperability with old kernels. Otherwise, old inodes get
+ * re-used with the upper 16 bits of the uid/gid intact
+ */
+ if(!ei->i_dtime) {
+ raw_inode->i_uid_high =
+ cpu_to_le16(high_16_bits(inode->i_uid));
+ raw_inode->i_gid_high =
+ cpu_to_le16(high_16_bits(inode->i_gid));
+ } else {
+ raw_inode->i_uid_high = 0;
+ raw_inode->i_gid_high = 0;
+ }
+ } else {
+ raw_inode->i_uid_low =
+ cpu_to_le16(fs_high2lowuid(inode->i_uid));
+ raw_inode->i_gid_low =
+ cpu_to_le16(fs_high2lowgid(inode->i_gid));
+ raw_inode->i_uid_high = 0;
+ raw_inode->i_gid_high = 0;
+ }
+ raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
+ raw_inode->i_size = cpu_to_le32(ei->i_disksize);
+ raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
+ raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
+ raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
+ raw_inode->i_blocks = cpu_to_le32(inode->i_blocks);
+ raw_inode->i_dtime = cpu_to_le32(ei->i_dtime);
+ raw_inode->i_flags = cpu_to_le32(ei->i_flags);
+#ifdef EXT4_FRAGMENTS
+ raw_inode->i_faddr = cpu_to_le32(ei->i_faddr);
+ raw_inode->i_frag = ei->i_frag_no;
+ raw_inode->i_fsize = ei->i_frag_size;
+#endif
+ if (EXT4_SB(inode->i_sb)->s_es->s_creator_os !=
+ cpu_to_le32(EXT4_OS_HURD))
+ raw_inode->i_file_acl_high =
+ cpu_to_le16(ei->i_file_acl >> 32);
+ raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl);
+ if (!S_ISREG(inode->i_mode)) {
+ raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl);
+ } else {
+ raw_inode->i_size_high =
+ cpu_to_le32(ei->i_disksize >> 32);
+ if (ei->i_disksize > 0x7fffffffULL) {
+ struct super_block *sb = inode->i_sb;
+ if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_LARGE_FILE) ||
+ EXT4_SB(sb)->s_es->s_rev_level ==
+ cpu_to_le32(EXT4_GOOD_OLD_REV)) {
+ /* If this is the first large file
+ * created, add a flag to the superblock.
+ */
+ err = ext4_journal_get_write_access(handle,
+ EXT4_SB(sb)->s_sbh);
+ if (err)
+ goto out_brelse;
+ ext4_update_dynamic_rev(sb);
+ EXT4_SET_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_LARGE_FILE);
+ sb->s_dirt = 1;
+ handle->h_sync = 1;
+ err = ext4_journal_dirty_metadata(handle,
+ EXT4_SB(sb)->s_sbh);
+ }
+ }
+ }
+ raw_inode->i_generation = cpu_to_le32(inode->i_generation);
+ if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
+ if (old_valid_dev(inode->i_rdev)) {
+ raw_inode->i_block[0] =
+ cpu_to_le32(old_encode_dev(inode->i_rdev));
+ raw_inode->i_block[1] = 0;
+ } else {
+ raw_inode->i_block[0] = 0;
+ raw_inode->i_block[1] =
+ cpu_to_le32(new_encode_dev(inode->i_rdev));
+ raw_inode->i_block[2] = 0;
+ }
+ } else for (block = 0; block < EXT4_N_BLOCKS; block++)
+ raw_inode->i_block[block] = ei->i_data[block];
+
+ if (ei->i_extra_isize)
+ raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
+
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ rc = ext4_journal_dirty_metadata(handle, bh);
+ if (!err)
+ err = rc;
+ ei->i_state &= ~EXT4_STATE_NEW;
+
+out_brelse:
+ brelse (bh);
+ ext4_std_error(inode->i_sb, err);
+ return err;
+}
+
+/*
+ * ext4_write_inode()
+ *
+ * We are called from a few places:
+ *
+ * - Within generic_file_write() for O_SYNC files.
+ * Here, there will be no transaction running. We wait for any running
+ * trasnaction to commit.
+ *
+ * - Within sys_sync(), kupdate and such.
+ * We wait on commit, if tol to.
+ *
+ * - Within prune_icache() (PF_MEMALLOC == true)
+ * Here we simply return. We can't afford to block kswapd on the
+ * journal commit.
+ *
+ * In all cases it is actually safe for us to return without doing anything,
+ * because the inode has been copied into a raw inode buffer in
+ * ext4_mark_inode_dirty(). This is a correctness thing for O_SYNC and for
+ * knfsd.
+ *
+ * Note that we are absolutely dependent upon all inode dirtiers doing the
+ * right thing: they *must* call mark_inode_dirty() after dirtying info in
+ * which we are interested.
+ *
+ * It would be a bug for them to not do this. The code:
+ *
+ * mark_inode_dirty(inode)
+ * stuff();
+ * inode->i_size = expr;
+ *
+ * is in error because a kswapd-driven write_inode() could occur while
+ * `stuff()' is running, and the new i_size will be lost. Plus the inode
+ * will no longer be on the superblock's dirty inode list.
+ */
+int ext4_write_inode(struct inode *inode, int wait)
+{
+ if (current->flags & PF_MEMALLOC)
+ return 0;
+
+ if (ext4_journal_current_handle()) {
+ jbd_debug(0, "called recursively, non-PF_MEMALLOC!\n");
+ dump_stack();
+ return -EIO;
+ }
+
+ if (!wait)
+ return 0;
+
+ return ext4_force_commit(inode->i_sb);
+}
+
+/*
+ * ext4_setattr()
+ *
+ * Called from notify_change.
+ *
+ * We want to trap VFS attempts to truncate the file as soon as
+ * possible. In particular, we want to make sure that when the VFS
+ * shrinks i_size, we put the inode on the orphan list and modify
+ * i_disksize immediately, so that during the subsequent flushing of
+ * dirty pages and freeing of disk blocks, we can guarantee that any
+ * commit will leave the blocks being flushed in an unused state on
+ * disk. (On recovery, the inode will get truncated and the blocks will
+ * be freed, so we have a strong guarantee that no future commit will
+ * leave these blocks visible to the user.)
+ *
+ * Called with inode->sem down.
+ */
+int ext4_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ struct inode *inode = dentry->d_inode;
+ int error, rc = 0;
+ const unsigned int ia_valid = attr->ia_valid;
+
+ error = inode_change_ok(inode, attr);
+ if (error)
+ return error;
+
+ if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
+ (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
+ handle_t *handle;
+
+ /* (user+group)*(old+new) structure, inode write (sb,
+ * inode block, ? - but truncate inode update has it) */
+ handle = ext4_journal_start(inode, 2*(EXT4_QUOTA_INIT_BLOCKS(inode->i_sb)+
+ EXT4_QUOTA_DEL_BLOCKS(inode->i_sb))+3);
+ if (IS_ERR(handle)) {
+ error = PTR_ERR(handle);
+ goto err_out;
+ }
+ error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
+ if (error) {
+ ext4_journal_stop(handle);
+ return error;
+ }
+ /* Update corresponding info in inode so that everything is in
+ * one transaction */
+ if (attr->ia_valid & ATTR_UID)
+ inode->i_uid = attr->ia_uid;
+ if (attr->ia_valid & ATTR_GID)
+ inode->i_gid = attr->ia_gid;
+ error = ext4_mark_inode_dirty(handle, inode);
+ ext4_journal_stop(handle);
+ }
+
+ if (S_ISREG(inode->i_mode) &&
+ attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) {
+ handle_t *handle;
+
+ handle = ext4_journal_start(inode, 3);
+ if (IS_ERR(handle)) {
+ error = PTR_ERR(handle);
+ goto err_out;
+ }
+
+ error = ext4_orphan_add(handle, inode);
+ EXT4_I(inode)->i_disksize = attr->ia_size;
+ rc = ext4_mark_inode_dirty(handle, inode);
+ if (!error)
+ error = rc;
+ ext4_journal_stop(handle);
+ }
+
+ rc = inode_setattr(inode, attr);
+
+ /* If inode_setattr's call to ext4_truncate failed to get a
+ * transaction handle at all, we need to clean up the in-core
+ * orphan list manually. */
+ if (inode->i_nlink)
+ ext4_orphan_del(NULL, inode);
+
+ if (!rc && (ia_valid & ATTR_MODE))
+ rc = ext4_acl_chmod(inode);
+
+err_out:
+ ext4_std_error(inode->i_sb, error);
+ if (!error)
+ error = rc;
+ return error;
+}
+
+
+/*
+ * How many blocks doth make a writepage()?
+ *
+ * With N blocks per page, it may be:
+ * N data blocks
+ * 2 indirect block
+ * 2 dindirect
+ * 1 tindirect
+ * N+5 bitmap blocks (from the above)
+ * N+5 group descriptor summary blocks
+ * 1 inode block
+ * 1 superblock.
+ * 2 * EXT4_SINGLEDATA_TRANS_BLOCKS for the quote files
+ *
+ * 3 * (N + 5) + 2 + 2 * EXT4_SINGLEDATA_TRANS_BLOCKS
+ *
+ * With ordered or writeback data it's the same, less the N data blocks.
+ *
+ * If the inode's direct blocks can hold an integral number of pages then a
+ * page cannot straddle two indirect blocks, and we can only touch one indirect
+ * and dindirect block, and the "5" above becomes "3".
+ *
+ * This still overestimates under most circumstances. If we were to pass the
+ * start and end offsets in here as well we could do block_to_path() on each
+ * block and work out the exact number of indirects which are touched. Pah.
+ */
+
+int ext4_writepage_trans_blocks(struct inode *inode)
+{
+ int bpp = ext4_journal_blocks_per_page(inode);
+ int indirects = (EXT4_NDIR_BLOCKS % bpp) ? 5 : 3;
+ int ret;
+
+ if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+ return ext4_ext_writepage_trans_blocks(inode, bpp);
+
+ if (ext4_should_journal_data(inode))
+ ret = 3 * (bpp + indirects) + 2;
+ else
+ ret = 2 * (bpp + indirects) + 2;
+
+#ifdef CONFIG_QUOTA
+ /* We know that structure was already allocated during DQUOT_INIT so
+ * we will be updating only the data blocks + inodes */
+ ret += 2*EXT4_QUOTA_TRANS_BLOCKS(inode->i_sb);
+#endif
+
+ return ret;
+}
+
+/*
+ * The caller must have previously called ext4_reserve_inode_write().
+ * Give this, we know that the caller already has write access to iloc->bh.
+ */
+int ext4_mark_iloc_dirty(handle_t *handle,
+ struct inode *inode, struct ext4_iloc *iloc)
+{
+ int err = 0;
+
+ /* the do_update_inode consumes one bh->b_count */
+ get_bh(iloc->bh);
+
+ /* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
+ err = ext4_do_update_inode(handle, inode, iloc);
+ put_bh(iloc->bh);
+ return err;
+}
+
+/*
+ * On success, We end up with an outstanding reference count against
+ * iloc->bh. This _must_ be cleaned up later.
+ */
+
+int
+ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
+ struct ext4_iloc *iloc)
+{
+ int err = 0;
+ if (handle) {
+ err = ext4_get_inode_loc(inode, iloc);
+ if (!err) {
+ BUFFER_TRACE(iloc->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, iloc->bh);
+ if (err) {
+ brelse(iloc->bh);
+ iloc->bh = NULL;
+ }
+ }
+ }
+ ext4_std_error(inode->i_sb, err);
+ return err;
+}
+
+/*
+ * What we do here is to mark the in-core inode as clean with respect to inode
+ * dirtiness (it may still be data-dirty).
+ * This means that the in-core inode may be reaped by prune_icache
+ * without having to perform any I/O. This is a very good thing,
+ * because *any* task may call prune_icache - even ones which
+ * have a transaction open against a different journal.
+ *
+ * Is this cheating? Not really. Sure, we haven't written the
+ * inode out, but prune_icache isn't a user-visible syncing function.
+ * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync)
+ * we start and wait on commits.
+ *
+ * Is this efficient/effective? Well, we're being nice to the system
+ * by cleaning up our inodes proactively so they can be reaped
+ * without I/O. But we are potentially leaving up to five seconds'
+ * worth of inodes floating about which prune_icache wants us to
+ * write out. One way to fix that would be to get prune_icache()
+ * to do a write_super() to free up some memory. It has the desired
+ * effect.
+ */
+int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
+{
+ struct ext4_iloc iloc;
+ int err;
+
+ might_sleep();
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (!err)
+ err = ext4_mark_iloc_dirty(handle, inode, &iloc);
+ return err;
+}
+
+/*
+ * ext4_dirty_inode() is called from __mark_inode_dirty()
+ *
+ * We're really interested in the case where a file is being extended.
+ * i_size has been changed by generic_commit_write() and we thus need
+ * to include the updated inode in the current transaction.
+ *
+ * Also, DQUOT_ALLOC_SPACE() will always dirty the inode when blocks
+ * are allocated to the file.
+ *
+ * If the inode is marked synchronous, we don't honour that here - doing
+ * so would cause a commit on atime updates, which we don't bother doing.
+ * We handle synchronous inodes at the highest possible level.
+ */
+void ext4_dirty_inode(struct inode *inode)
+{
+ handle_t *current_handle = ext4_journal_current_handle();
+ handle_t *handle;
+
+ handle = ext4_journal_start(inode, 2);
+ if (IS_ERR(handle))
+ goto out;
+ if (current_handle &&
+ current_handle->h_transaction != handle->h_transaction) {
+ /* This task has a transaction open against a different fs */
+ printk(KERN_EMERG "%s: transactions do not match!\n",
+ __FUNCTION__);
+ } else {
+ jbd_debug(5, "marking dirty. outer handle=%p\n",
+ current_handle);
+ ext4_mark_inode_dirty(handle, inode);
+ }
+ ext4_journal_stop(handle);
+out:
+ return;
+}
+
+#if 0
+/*
+ * Bind an inode's backing buffer_head into this transaction, to prevent
+ * it from being flushed to disk early. Unlike
+ * ext4_reserve_inode_write, this leaves behind no bh reference and
+ * returns no iloc structure, so the caller needs to repeat the iloc
+ * lookup to mark the inode dirty later.
+ */
+static int ext4_pin_inode(handle_t *handle, struct inode *inode)
+{
+ struct ext4_iloc iloc;
+
+ int err = 0;
+ if (handle) {
+ err = ext4_get_inode_loc(inode, &iloc);
+ if (!err) {
+ BUFFER_TRACE(iloc.bh, "get_write_access");
+ err = jbd2_journal_get_write_access(handle, iloc.bh);
+ if (!err)
+ err = ext4_journal_dirty_metadata(handle,
+ iloc.bh);
+ brelse(iloc.bh);
+ }
+ }
+ ext4_std_error(inode->i_sb, err);
+ return err;
+}
+#endif
+
+int ext4_change_inode_journal_flag(struct inode *inode, int val)
+{
+ journal_t *journal;
+ handle_t *handle;
+ int err;
+
+ /*
+ * We have to be very careful here: changing a data block's
+ * journaling status dynamically is dangerous. If we write a
+ * data block to the journal, change the status and then delete
+ * that block, we risk forgetting to revoke the old log record
+ * from the journal and so a subsequent replay can corrupt data.
+ * So, first we make sure that the journal is empty and that
+ * nobody is changing anything.
+ */
+
+ journal = EXT4_JOURNAL(inode);
+ if (is_journal_aborted(journal) || IS_RDONLY(inode))
+ return -EROFS;
+
+ jbd2_journal_lock_updates(journal);
+ jbd2_journal_flush(journal);
+
+ /*
+ * OK, there are no updates running now, and all cached data is
+ * synced to disk. We are now in a completely consistent state
+ * which doesn't have anything in the journal, and we know that
+ * no filesystem updates are running, so it is safe to modify
+ * the inode's in-core data-journaling state flag now.
+ */
+
+ if (val)
+ EXT4_I(inode)->i_flags |= EXT4_JOURNAL_DATA_FL;
+ else
+ EXT4_I(inode)->i_flags &= ~EXT4_JOURNAL_DATA_FL;
+ ext4_set_aops(inode);
+
+ jbd2_journal_unlock_updates(journal);
+
+ /* Finally we can mark the inode as dirty. */
+
+ handle = ext4_journal_start(inode, 1);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ err = ext4_mark_inode_dirty(handle, inode);
+ handle->h_sync = 1;
+ ext4_journal_stop(handle);
+ ext4_std_error(inode->i_sb, err);
+
+ return err;
+}
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
new file mode 100644
index 000000000000..22a737c306c7
--- /dev/null
+++ b/fs/ext4/ioctl.c
@@ -0,0 +1,306 @@
+/*
+ * linux/fs/ext4/ioctl.c
+ *
+ * Copyright (C) 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ */
+
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/capability.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/time.h>
+#include <linux/compat.h>
+#include <linux/smp_lock.h>
+#include <asm/uaccess.h>
+
+int ext4_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ unsigned int flags;
+ unsigned short rsv_window_size;
+
+ ext4_debug ("cmd = %u, arg = %lu\n", cmd, arg);
+
+ switch (cmd) {
+ case EXT4_IOC_GETFLAGS:
+ flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
+ return put_user(flags, (int __user *) arg);
+ case EXT4_IOC_SETFLAGS: {
+ handle_t *handle = NULL;
+ int err;
+ struct ext4_iloc iloc;
+ unsigned int oldflags;
+ unsigned int jflag;
+
+ if (IS_RDONLY(inode))
+ return -EROFS;
+
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+ return -EACCES;
+
+ if (get_user(flags, (int __user *) arg))
+ return -EFAULT;
+
+ if (!S_ISDIR(inode->i_mode))
+ flags &= ~EXT4_DIRSYNC_FL;
+
+ mutex_lock(&inode->i_mutex);
+ oldflags = ei->i_flags;
+
+ /* The JOURNAL_DATA flag is modifiable only by root */
+ jflag = flags & EXT4_JOURNAL_DATA_FL;
+
+ /*
+ * The IMMUTABLE and APPEND_ONLY flags can only be changed by
+ * the relevant capability.
+ *
+ * This test looks nicer. Thanks to Pauline Middelink
+ */
+ if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ mutex_unlock(&inode->i_mutex);
+ return -EPERM;
+ }
+ }
+
+ /*
+ * The JOURNAL_DATA flag can only be changed by
+ * the relevant capability.
+ */
+ if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
+ if (!capable(CAP_SYS_RESOURCE)) {
+ mutex_unlock(&inode->i_mutex);
+ return -EPERM;
+ }
+ }
+
+
+ handle = ext4_journal_start(inode, 1);
+ if (IS_ERR(handle)) {
+ mutex_unlock(&inode->i_mutex);
+ return PTR_ERR(handle);
+ }
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err)
+ goto flags_err;
+
+ flags = flags & EXT4_FL_USER_MODIFIABLE;
+ flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE;
+ ei->i_flags = flags;
+
+ ext4_set_inode_flags(inode);
+ inode->i_ctime = CURRENT_TIME_SEC;
+
+ err = ext4_mark_iloc_dirty(handle, inode, &iloc);
+flags_err:
+ ext4_journal_stop(handle);
+ if (err) {
+ mutex_unlock(&inode->i_mutex);
+ return err;
+ }
+
+ if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
+ err = ext4_change_inode_journal_flag(inode, jflag);
+ mutex_unlock(&inode->i_mutex);
+ return err;
+ }
+ case EXT4_IOC_GETVERSION:
+ case EXT4_IOC_GETVERSION_OLD:
+ return put_user(inode->i_generation, (int __user *) arg);
+ case EXT4_IOC_SETVERSION:
+ case EXT4_IOC_SETVERSION_OLD: {
+ handle_t *handle;
+ struct ext4_iloc iloc;
+ __u32 generation;
+ int err;
+
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+ return -EPERM;
+ if (IS_RDONLY(inode))
+ return -EROFS;
+ if (get_user(generation, (int __user *) arg))
+ return -EFAULT;
+
+ handle = ext4_journal_start(inode, 1);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err == 0) {
+ inode->i_ctime = CURRENT_TIME_SEC;
+ inode->i_generation = generation;
+ err = ext4_mark_iloc_dirty(handle, inode, &iloc);
+ }
+ ext4_journal_stop(handle);
+ return err;
+ }
+#ifdef CONFIG_JBD_DEBUG
+ case EXT4_IOC_WAIT_FOR_READONLY:
+ /*
+ * This is racy - by the time we're woken up and running,
+ * the superblock could be released. And the module could
+ * have been unloaded. So sue me.
+ *
+ * Returns 1 if it slept, else zero.
+ */
+ {
+ struct super_block *sb = inode->i_sb;
+ DECLARE_WAITQUEUE(wait, current);
+ int ret = 0;
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
+ if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) {
+ schedule();
+ ret = 1;
+ }
+ remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
+ return ret;
+ }
+#endif
+ case EXT4_IOC_GETRSVSZ:
+ if (test_opt(inode->i_sb, RESERVATION)
+ && S_ISREG(inode->i_mode)
+ && ei->i_block_alloc_info) {
+ rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
+ return put_user(rsv_window_size, (int __user *)arg);
+ }
+ return -ENOTTY;
+ case EXT4_IOC_SETRSVSZ: {
+
+ if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
+ return -ENOTTY;
+
+ if (IS_RDONLY(inode))
+ return -EROFS;
+
+ if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
+ return -EACCES;
+
+ if (get_user(rsv_window_size, (int __user *)arg))
+ return -EFAULT;
+
+ if (rsv_window_size > EXT4_MAX_RESERVE_BLOCKS)
+ rsv_window_size = EXT4_MAX_RESERVE_BLOCKS;
+
+ /*
+ * need to allocate reservation structure for this inode
+ * before set the window size
+ */
+ mutex_lock(&ei->truncate_mutex);
+ if (!ei->i_block_alloc_info)
+ ext4_init_block_alloc_info(inode);
+
+ if (ei->i_block_alloc_info){
+ struct ext4_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
+ rsv->rsv_goal_size = rsv_window_size;
+ }
+ mutex_unlock(&ei->truncate_mutex);
+ return 0;
+ }
+ case EXT4_IOC_GROUP_EXTEND: {
+ ext4_fsblk_t n_blocks_count;
+ struct super_block *sb = inode->i_sb;
+ int err;
+
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ if (IS_RDONLY(inode))
+ return -EROFS;
+
+ if (get_user(n_blocks_count, (__u32 __user *)arg))
+ return -EFAULT;
+
+ err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
+ jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
+ jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+ jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+
+ return err;
+ }
+ case EXT4_IOC_GROUP_ADD: {
+ struct ext4_new_group_data input;
+ struct super_block *sb = inode->i_sb;
+ int err;
+
+ if (!capable(CAP_SYS_RESOURCE))
+ return -EPERM;
+
+ if (IS_RDONLY(inode))
+ return -EROFS;
+
+ if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
+ sizeof(input)))
+ return -EFAULT;
+
+ err = ext4_group_add(sb, &input);
+ jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
+ jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+ jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+
+ return err;
+ }
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ int ret;
+
+ /* These are just misnamed, they actually get/put from/to user an int */
+ switch (cmd) {
+ case EXT4_IOC32_GETFLAGS:
+ cmd = EXT4_IOC_GETFLAGS;
+ break;
+ case EXT4_IOC32_SETFLAGS:
+ cmd = EXT4_IOC_SETFLAGS;
+ break;
+ case EXT4_IOC32_GETVERSION:
+ cmd = EXT4_IOC_GETVERSION;
+ break;
+ case EXT4_IOC32_SETVERSION:
+ cmd = EXT4_IOC_SETVERSION;
+ break;
+ case EXT4_IOC32_GROUP_EXTEND:
+ cmd = EXT4_IOC_GROUP_EXTEND;
+ break;
+ case EXT4_IOC32_GETVERSION_OLD:
+ cmd = EXT4_IOC_GETVERSION_OLD;
+ break;
+ case EXT4_IOC32_SETVERSION_OLD:
+ cmd = EXT4_IOC_SETVERSION_OLD;
+ break;
+#ifdef CONFIG_JBD_DEBUG
+ case EXT4_IOC32_WAIT_FOR_READONLY:
+ cmd = EXT4_IOC_WAIT_FOR_READONLY;
+ break;
+#endif
+ case EXT4_IOC32_GETRSVSZ:
+ cmd = EXT4_IOC_GETRSVSZ;
+ break;
+ case EXT4_IOC32_SETRSVSZ:
+ cmd = EXT4_IOC_SETRSVSZ;
+ break;
+ case EXT4_IOC_GROUP_ADD:
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ lock_kernel();
+ ret = ext4_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
+ unlock_kernel();
+ return ret;
+}
+#endif
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
new file mode 100644
index 000000000000..8b1bd03d20f5
--- /dev/null
+++ b/fs/ext4/namei.c
@@ -0,0 +1,2395 @@
+/*
+ * linux/fs/ext4/namei.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/namei.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ * Directory entry file type support and forward compatibility hooks
+ * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
+ * Hash Tree Directory indexing (c)
+ * Daniel Phillips, 2001
+ * Hash Tree Directory indexing porting
+ * Christopher Li, 2002
+ * Hash Tree Directory indexing cleanup
+ * Theodore Ts'o, 2002
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include <linux/jbd2.h>
+#include <linux/time.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/quotaops.h>
+#include <linux/buffer_head.h>
+#include <linux/bio.h>
+#include <linux/smp_lock.h>
+
+#include "namei.h"
+#include "xattr.h"
+#include "acl.h"
+
+/*
+ * define how far ahead to read directories while searching them.
+ */
+#define NAMEI_RA_CHUNKS 2
+#define NAMEI_RA_BLOCKS 4
+#define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+#define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b))
+
+static struct buffer_head *ext4_append(handle_t *handle,
+ struct inode *inode,
+ u32 *block, int *err)
+{
+ struct buffer_head *bh;
+
+ *block = inode->i_size >> inode->i_sb->s_blocksize_bits;
+
+ if ((bh = ext4_bread(handle, inode, *block, 1, err))) {
+ inode->i_size += inode->i_sb->s_blocksize;
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ ext4_journal_get_write_access(handle,bh);
+ }
+ return bh;
+}
+
+#ifndef assert
+#define assert(test) J_ASSERT(test)
+#endif
+
+#ifndef swap
+#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0)
+#endif
+
+#ifdef DX_DEBUG
+#define dxtrace(command) command
+#else
+#define dxtrace(command)
+#endif
+
+struct fake_dirent
+{
+ __le32 inode;
+ __le16 rec_len;
+ u8 name_len;
+ u8 file_type;
+};
+
+struct dx_countlimit
+{
+ __le16 limit;
+ __le16 count;
+};
+
+struct dx_entry
+{
+ __le32 hash;
+ __le32 block;
+};
+
+/*
+ * dx_root_info is laid out so that if it should somehow get overlaid by a
+ * dirent the two low bits of the hash version will be zero. Therefore, the
+ * hash version mod 4 should never be 0. Sincerely, the paranoia department.
+ */
+
+struct dx_root
+{
+ struct fake_dirent dot;
+ char dot_name[4];
+ struct fake_dirent dotdot;
+ char dotdot_name[4];
+ struct dx_root_info
+ {
+ __le32 reserved_zero;
+ u8 hash_version;
+ u8 info_length; /* 8 */
+ u8 indirect_levels;
+ u8 unused_flags;
+ }
+ info;
+ struct dx_entry entries[0];
+};
+
+struct dx_node
+{
+ struct fake_dirent fake;
+ struct dx_entry entries[0];
+};
+
+
+struct dx_frame
+{
+ struct buffer_head *bh;
+ struct dx_entry *entries;
+ struct dx_entry *at;
+};
+
+struct dx_map_entry
+{
+ u32 hash;
+ u32 offs;
+};
+
+#ifdef CONFIG_EXT4_INDEX
+static inline unsigned dx_get_block (struct dx_entry *entry);
+static void dx_set_block (struct dx_entry *entry, unsigned value);
+static inline unsigned dx_get_hash (struct dx_entry *entry);
+static void dx_set_hash (struct dx_entry *entry, unsigned value);
+static unsigned dx_get_count (struct dx_entry *entries);
+static unsigned dx_get_limit (struct dx_entry *entries);
+static void dx_set_count (struct dx_entry *entries, unsigned value);
+static void dx_set_limit (struct dx_entry *entries, unsigned value);
+static unsigned dx_root_limit (struct inode *dir, unsigned infosize);
+static unsigned dx_node_limit (struct inode *dir);
+static struct dx_frame *dx_probe(struct dentry *dentry,
+ struct inode *dir,
+ struct dx_hash_info *hinfo,
+ struct dx_frame *frame,
+ int *err);
+static void dx_release (struct dx_frame *frames);
+static int dx_make_map (struct ext4_dir_entry_2 *de, int size,
+ struct dx_hash_info *hinfo, struct dx_map_entry map[]);
+static void dx_sort_map(struct dx_map_entry *map, unsigned count);
+static struct ext4_dir_entry_2 *dx_move_dirents (char *from, char *to,
+ struct dx_map_entry *offsets, int count);
+static struct ext4_dir_entry_2* dx_pack_dirents (char *base, int size);
+static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
+static int ext4_htree_next_block(struct inode *dir, __u32 hash,
+ struct dx_frame *frame,
+ struct dx_frame *frames,
+ __u32 *start_hash);
+static struct buffer_head * ext4_dx_find_entry(struct dentry *dentry,
+ struct ext4_dir_entry_2 **res_dir, int *err);
+static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
+ struct inode *inode);
+
+/*
+ * Future: use high four bits of block for coalesce-on-delete flags
+ * Mask them off for now.
+ */
+
+static inline unsigned dx_get_block (struct dx_entry *entry)
+{
+ return le32_to_cpu(entry->block) & 0x00ffffff;
+}
+
+static inline void dx_set_block (struct dx_entry *entry, unsigned value)
+{
+ entry->block = cpu_to_le32(value);
+}
+
+static inline unsigned dx_get_hash (struct dx_entry *entry)
+{
+ return le32_to_cpu(entry->hash);
+}
+
+static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
+{
+ entry->hash = cpu_to_le32(value);
+}
+
+static inline unsigned dx_get_count (struct dx_entry *entries)
+{
+ return le16_to_cpu(((struct dx_countlimit *) entries)->count);
+}
+
+static inline unsigned dx_get_limit (struct dx_entry *entries)
+{
+ return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
+}
+
+static inline void dx_set_count (struct dx_entry *entries, unsigned value)
+{
+ ((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
+}
+
+static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
+{
+ ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
+}
+
+static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
+{
+ unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(1) -
+ EXT4_DIR_REC_LEN(2) - infosize;
+ return 0? 20: entry_space / sizeof(struct dx_entry);
+}
+
+static inline unsigned dx_node_limit (struct inode *dir)
+{
+ unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0);
+ return 0? 22: entry_space / sizeof(struct dx_entry);
+}
+
+/*
+ * Debug
+ */
+#ifdef DX_DEBUG
+static void dx_show_index (char * label, struct dx_entry *entries)
+{
+ int i, n = dx_get_count (entries);
+ printk("%s index ", label);
+ for (i = 0; i < n; i++) {
+ printk("%x->%u ", i? dx_get_hash(entries + i) :
+ 0, dx_get_block(entries + i));
+ }
+ printk("\n");
+}
+
+struct stats
+{
+ unsigned names;
+ unsigned space;
+ unsigned bcount;
+};
+
+static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_entry_2 *de,
+ int size, int show_names)
+{
+ unsigned names = 0, space = 0;
+ char *base = (char *) de;
+ struct dx_hash_info h = *hinfo;
+
+ printk("names: ");
+ while ((char *) de < base + size)
+ {
+ if (de->inode)
+ {
+ if (show_names)
+ {
+ int len = de->name_len;
+ char *name = de->name;
+ while (len--) printk("%c", *name++);
+ ext4fs_dirhash(de->name, de->name_len, &h);
+ printk(":%x.%u ", h.hash,
+ ((char *) de - base));
+ }
+ space += EXT4_DIR_REC_LEN(de->name_len);
+ names++;
+ }
+ de = (struct ext4_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
+ }
+ printk("(%i)\n", names);
+ return (struct stats) { names, space, 1 };
+}
+
+struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
+ struct dx_entry *entries, int levels)
+{
+ unsigned blocksize = dir->i_sb->s_blocksize;
+ unsigned count = dx_get_count (entries), names = 0, space = 0, i;
+ unsigned bcount = 0;
+ struct buffer_head *bh;
+ int err;
+ printk("%i indexed blocks...\n", count);
+ for (i = 0; i < count; i++, entries++)
+ {
+ u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
+ u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
+ struct stats stats;
+ printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range);
+ if (!(bh = ext4_bread (NULL,dir, block, 0,&err))) continue;
+ stats = levels?
+ dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
+ dx_show_leaf(hinfo, (struct ext4_dir_entry_2 *) bh->b_data, blocksize, 0);
+ names += stats.names;
+ space += stats.space;
+ bcount += stats.bcount;
+ brelse (bh);
+ }
+ if (bcount)
+ printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ",
+ names, space/bcount,(space/bcount)*100/blocksize);
+ return (struct stats) { names, space, bcount};
+}
+#endif /* DX_DEBUG */
+
+/*
+ * Probe for a directory leaf block to search.
+ *
+ * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
+ * error in the directory index, and the caller should fall back to
+ * searching the directory normally. The callers of dx_probe **MUST**
+ * check for this error code, and make sure it never gets reflected
+ * back to userspace.
+ */
+static struct dx_frame *
+dx_probe(struct dentry *dentry, struct inode *dir,
+ struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
+{
+ unsigned count, indirect;
+ struct dx_entry *at, *entries, *p, *q, *m;
+ struct dx_root *root;
+ struct buffer_head *bh;
+ struct dx_frame *frame = frame_in;
+ u32 hash;
+
+ frame->bh = NULL;
+ if (dentry)
+ dir = dentry->d_parent->d_inode;
+ if (!(bh = ext4_bread (NULL,dir, 0, 0, err)))
+ goto fail;
+ root = (struct dx_root *) bh->b_data;
+ if (root->info.hash_version != DX_HASH_TEA &&
+ root->info.hash_version != DX_HASH_HALF_MD4 &&
+ root->info.hash_version != DX_HASH_LEGACY) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "Unrecognised inode hash code %d",
+ root->info.hash_version);
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail;
+ }
+ hinfo->hash_version = root->info.hash_version;
+ hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ if (dentry)
+ ext4fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
+ hash = hinfo->hash;
+
+ if (root->info.unused_flags & 1) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "Unimplemented inode hash flags: %#06x",
+ root->info.unused_flags);
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail;
+ }
+
+ if ((indirect = root->info.indirect_levels) > 1) {
+ ext4_warning(dir->i_sb, __FUNCTION__,
+ "Unimplemented inode hash depth: %#06x",
+ root->info.indirect_levels);
+ brelse(bh);
+ *err = ERR_BAD_DX_DIR;
+ goto fail;
+ }
+
+ entries = (struct dx_entry *) (((char *)&root->info) +
+ root->info.info_length);
+ assert(dx_get_limit(entries) == dx_root_limit(dir,
+ root->info.info_length));
+ dxtrace (printk("Look up %x", hash));
+ while (1)
+ {
+ count = dx_get_count(entries);
+ assert (count && count <= dx_get_limit(entries));
+ p = entries + 1;
+ q = entries + count - 1;
+ while (p <= q)
+ {
+ m = p + (q - p)/2;
+ dxtrace(printk("."));
+ if (dx_get_hash(m) > hash)
+ q = m - 1;
+ else
+ p = m + 1;
+ }
+
+ if (0) // linear search cross check
+ {
+ unsigned n = count - 1;
+ at = entries;
+ while (n--)
+ {
+ dxtrace(printk(","));
+ if (dx_get_hash(++at) > hash)
+ {
+ at--;
+ break;
+ }
+ }
+ assert (at == p - 1);
+ }
+
+ at = p - 1;
+ dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
+ frame->bh = bh;
+ frame->entries = entries;
+ frame->at = at;
+ if (!indirect--) return frame;
+ if (!(bh = ext4_bread (NULL,dir, dx_get_block(at), 0, err)))
+ goto fail2;
+ at = entries = ((struct dx_node *) bh->b_data)->entries;
+ assert (dx_get_limit(entries) == dx_node_limit (dir));
+ frame++;
+ }
+fail2:
+ while (frame >= frame_in) {
+ brelse(frame->bh);
+ frame--;
+ }
+fail:
+ return NULL;
+}
+
+static void dx_release (struct dx_frame *frames)
+{
+ if (frames[0].bh == NULL)
+ return;
+
+ if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
+ brelse(frames[1].bh);
+ brelse(frames[0].bh);
+}
+
+/*
+ * This function increments the frame pointer to search the next leaf
+ * block, and reads in the necessary intervening nodes if the search
+ * should be necessary. Whether or not the search is necessary is
+ * controlled by the hash parameter. If the hash value is even, then
+ * the search is only continued if the next block starts with that
+ * hash value. This is used if we are searching for a specific file.
+ *
+ * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
+ *
+ * This function returns 1 if the caller should continue to search,
+ * or 0 if it should not. If there is an error reading one of the
+ * index blocks, it will a negative error code.
+ *
+ * If start_hash is non-null, it will be filled in with the starting
+ * hash of the next page.
+ */
+static int ext4_htree_next_block(struct inode *dir, __u32 hash,
+ struct dx_frame *frame,
+ struct dx_frame *frames,
+ __u32 *start_hash)
+{
+ struct dx_frame *p;
+ struct buffer_head *bh;
+ int err, num_frames = 0;
+ __u32 bhash;
+
+ p = frame;
+ /*
+ * Find the next leaf page by incrementing the frame pointer.
+ * If we run out of entries in the interior node, loop around and
+ * increment pointer in the parent node. When we break out of
+ * this loop, num_frames indicates the number of interior
+ * nodes need to be read.
+ */
+ while (1) {
+ if (++(p->at) < p->entries + dx_get_count(p->entries))
+ break;
+ if (p == frames)
+ return 0;
+ num_frames++;
+ p--;
+ }
+
+ /*
+ * If the hash is 1, then continue only if the next page has a
+ * continuation hash of any value. This is used for readdir
+ * handling. Otherwise, check to see if the hash matches the
+ * desired contiuation hash. If it doesn't, return since
+ * there's no point to read in the successive index pages.
+ */
+ bhash = dx_get_hash(p->at);
+ if (start_hash)
+ *start_hash = bhash;
+ if ((hash & 1) == 0) {
+ if ((bhash & ~1) != hash)
+ return 0;
+ }
+ /*
+ * If the hash is HASH_NB_ALWAYS, we always go to the next
+ * block so no check is necessary
+ */
+ while (num_frames--) {
+ if (!(bh = ext4_bread(NULL, dir, dx_get_block(p->at),
+ 0, &err)))
+ return err; /* Failure */
+ p++;
+ brelse (p->bh);
+ p->bh = bh;
+ p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
+ }
+ return 1;
+}
+
+
+/*
+ * p is at least 6 bytes before the end of page
+ */
+static inline struct ext4_dir_entry_2 *ext4_next_entry(struct ext4_dir_entry_2 *p)
+{
+ return (struct ext4_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
+}
+
+/*
+ * This function fills a red-black tree with information from a
+ * directory block. It returns the number directory entries loaded
+ * into the tree. If there is an error it is returned in err.
+ */
+static int htree_dirblock_to_tree(struct file *dir_file,
+ struct inode *dir, int block,
+ struct dx_hash_info *hinfo,
+ __u32 start_hash, __u32 start_minor_hash)
+{
+ struct buffer_head *bh;
+ struct ext4_dir_entry_2 *de, *top;
+ int err, count = 0;
+
+ dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
+ if (!(bh = ext4_bread (NULL, dir, block, 0, &err)))
+ return err;
+
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ top = (struct ext4_dir_entry_2 *) ((char *) de +
+ dir->i_sb->s_blocksize -
+ EXT4_DIR_REC_LEN(0));
+ for (; de < top; de = ext4_next_entry(de)) {
+ ext4fs_dirhash(de->name, de->name_len, hinfo);
+ if ((hinfo->hash < start_hash) ||
+ ((hinfo->hash == start_hash) &&
+ (hinfo->minor_hash < start_minor_hash)))
+ continue;
+ if (de->inode == 0)
+ continue;
+ if ((err = ext4_htree_store_dirent(dir_file,
+ hinfo->hash, hinfo->minor_hash, de)) != 0) {
+ brelse(bh);
+ return err;
+ }
+ count++;
+ }
+ brelse(bh);
+ return count;
+}
+
+
+/*
+ * This function fills a red-black tree with information from a
+ * directory. We start scanning the directory in hash order, starting
+ * at start_hash and start_minor_hash.
+ *
+ * This function returns the number of entries inserted into the tree,
+ * or a negative error code.
+ */
+int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
+ __u32 start_minor_hash, __u32 *next_hash)
+{
+ struct dx_hash_info hinfo;
+ struct ext4_dir_entry_2 *de;
+ struct dx_frame frames[2], *frame;
+ struct inode *dir;
+ int block, err;
+ int count = 0;
+ int ret;
+ __u32 hashval;
+
+ dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
+ start_minor_hash));
+ dir = dir_file->f_dentry->d_inode;
+ if (!(EXT4_I(dir)->i_flags & EXT4_INDEX_FL)) {
+ hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
+ hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
+ start_hash, start_minor_hash);
+ *next_hash = ~0;
+ return count;
+ }
+ hinfo.hash = start_hash;
+ hinfo.minor_hash = 0;
+ frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err);
+ if (!frame)
+ return err;
+
+ /* Add '.' and '..' from the htree header */
+ if (!start_hash && !start_minor_hash) {
+ de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
+ if ((err = ext4_htree_store_dirent(dir_file, 0, 0, de)) != 0)
+ goto errout;
+ count++;
+ }
+ if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
+ de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
+ de = ext4_next_entry(de);
+ if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
+ goto errout;
+ count++;
+ }
+
+ while (1) {
+ block = dx_get_block(frame->at);
+ ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
+ start_hash, start_minor_hash);
+ if (ret < 0) {
+ err = ret;
+ goto errout;
+ }
+ count += ret;
+ hashval = ~0;
+ ret = ext4_htree_next_block(dir, HASH_NB_ALWAYS,
+ frame, frames, &hashval);
+ *next_hash = hashval;
+ if (ret < 0) {
+ err = ret;
+ goto errout;
+ }
+ /*
+ * Stop if: (a) there are no more entries, or
+ * (b) we have inserted at least one entry and the
+ * next hash value is not a continuation
+ */
+ if ((ret == 0) ||
+ (count && ((hashval & 1) == 0)))
+ break;
+ }
+ dx_release(frames);
+ dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n",
+ count, *next_hash));
+ return count;
+errout:
+ dx_release(frames);
+ return (err);
+}
+
+
+/*
+ * Directory block splitting, compacting
+ */
+
+static int dx_make_map (struct ext4_dir_entry_2 *de, int size,
+ struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
+{
+ int count = 0;
+ char *base = (char *) de;
+ struct dx_hash_info h = *hinfo;
+
+ while ((char *) de < base + size)
+ {
+ if (de->name_len && de->inode) {
+ ext4fs_dirhash(de->name, de->name_len, &h);
+ map_tail--;
+ map_tail->hash = h.hash;
+ map_tail->offs = (u32) ((char *) de - base);
+ count++;
+ cond_resched();
+ }
+ /* XXX: do we need to check rec_len == 0 case? -Chris */
+ de = (struct ext4_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
+ }
+ return count;
+}
+
+static void dx_sort_map (struct dx_map_entry *map, unsigned count)
+{
+ struct dx_map_entry *p, *q, *top = map + count - 1;
+ int more;
+ /* Combsort until bubble sort doesn't suck */
+ while (count > 2) {
+ count = count*10/13;
+ if (count - 9 < 2) /* 9, 10 -> 11 */
+ count = 11;
+ for (p = top, q = p - count; q >= map; p--, q--)
+ if (p->hash < q->hash)
+ swap(*p, *q);
+ }
+ /* Garden variety bubble sort */
+ do {
+ more = 0;
+ q = top;
+ while (q-- > map) {
+ if (q[1].hash >= q[0].hash)
+ continue;
+ swap(*(q+1), *q);
+ more = 1;
+ }
+ } while(more);
+}
+
+static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
+{
+ struct dx_entry *entries = frame->entries;
+ struct dx_entry *old = frame->at, *new = old + 1;
+ int count = dx_get_count(entries);
+
+ assert(count < dx_get_limit(entries));
+ assert(old < entries + count);
+ memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
+ dx_set_hash(new, hash);
+ dx_set_block(new, block);
+ dx_set_count(entries, count + 1);
+}
+#endif
+
+
+static void ext4_update_dx_flag(struct inode *inode)
+{
+ if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_COMPAT_DIR_INDEX))
+ EXT4_I(inode)->i_flags &= ~EXT4_INDEX_FL;
+}
+
+/*
+ * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure.
+ *
+ * `len <= EXT4_NAME_LEN' is guaranteed by caller.
+ * `de != NULL' is guaranteed by caller.
+ */
+static inline int ext4_match (int len, const char * const name,
+ struct ext4_dir_entry_2 * de)
+{
+ if (len != de->name_len)
+ return 0;
+ if (!de->inode)
+ return 0;
+ return !memcmp(name, de->name, len);
+}
+
+/*
+ * Returns 0 if not found, -1 on failure, and 1 on success
+ */
+static inline int search_dirblock(struct buffer_head * bh,
+ struct inode *dir,
+ struct dentry *dentry,
+ unsigned long offset,
+ struct ext4_dir_entry_2 ** res_dir)
+{
+ struct ext4_dir_entry_2 * de;
+ char * dlimit;
+ int de_len;
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ dlimit = bh->b_data + dir->i_sb->s_blocksize;
+ while ((char *) de < dlimit) {
+ /* this code is executed quadratically often */
+ /* do minimal checking `by hand' */
+
+ if ((char *) de + namelen <= dlimit &&
+ ext4_match (namelen, name, de)) {
+ /* found a match - just to be sure, do a full check */
+ if (!ext4_check_dir_entry("ext4_find_entry",
+ dir, de, bh, offset))
+ return -1;
+ *res_dir = de;
+ return 1;
+ }
+ /* prevent looping on a bad block */
+ de_len = le16_to_cpu(de->rec_len);
+ if (de_len <= 0)
+ return -1;
+ offset += de_len;
+ de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
+ }
+ return 0;
+}
+
+
+/*
+ * ext4_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the cache buffer in which the entry was found, and the entry
+ * itself (as a parameter - res_dir). It does NOT read the inode of the
+ * entry - you'll have to do that yourself if you want to.
+ *
+ * The returned buffer_head has ->b_count elevated. The caller is expected
+ * to brelse() it when appropriate.
+ */
+static struct buffer_head * ext4_find_entry (struct dentry *dentry,
+ struct ext4_dir_entry_2 ** res_dir)
+{
+ struct super_block * sb;
+ struct buffer_head * bh_use[NAMEI_RA_SIZE];
+ struct buffer_head * bh, *ret = NULL;
+ unsigned long start, block, b;
+ int ra_max = 0; /* Number of bh's in the readahead
+ buffer, bh_use[] */
+ int ra_ptr = 0; /* Current index into readahead
+ buffer */
+ int num = 0;
+ int nblocks, i, err;
+ struct inode *dir = dentry->d_parent->d_inode;
+ int namelen;
+ const u8 *name;
+ unsigned blocksize;
+
+ *res_dir = NULL;
+ sb = dir->i_sb;
+ blocksize = sb->s_blocksize;
+ namelen = dentry->d_name.len;
+ name = dentry->d_name.name;
+ if (namelen > EXT4_NAME_LEN)
+ return NULL;
+#ifdef CONFIG_EXT4_INDEX
+ if (is_dx(dir)) {
+ bh = ext4_dx_find_entry(dentry, res_dir, &err);
+ /*
+ * On success, or if the error was file not found,
+ * return. Otherwise, fall back to doing a search the
+ * old fashioned way.
+ */
+ if (bh || (err != ERR_BAD_DX_DIR))
+ return bh;
+ dxtrace(printk("ext4_find_entry: dx failed, falling back\n"));
+ }
+#endif
+ nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
+ start = EXT4_I(dir)->i_dir_start_lookup;
+ if (start >= nblocks)
+ start = 0;
+ block = start;
+restart:
+ do {
+ /*
+ * We deal with the read-ahead logic here.
+ */
+ if (ra_ptr >= ra_max) {
+ /* Refill the readahead buffer */
+ ra_ptr = 0;
+ b = block;
+ for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
+ /*
+ * Terminate if we reach the end of the
+ * directory and must wrap, or if our
+ * search has finished at this block.
+ */
+ if (b >= nblocks || (num && block == start)) {
+ bh_use[ra_max] = NULL;
+ break;
+ }
+ num++;
+ bh = ext4_getblk(NULL, dir, b++, 0, &err);
+ bh_use[ra_max] = bh;
+ if (bh)
+ ll_rw_block(READ_META, 1, &bh);
+ }
+ }
+ if ((bh = bh_use[ra_ptr++]) == NULL)
+ goto next;
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh)) {
+ /* read error, skip block & hope for the best */
+ ext4_error(sb, __FUNCTION__, "reading directory #%lu "
+ "offset %lu", dir->i_ino, block);
+ brelse(bh);
+ goto next;
+ }
+ i = search_dirblock(bh, dir, dentry,
+ block << EXT4_BLOCK_SIZE_BITS(sb), res_dir);
+ if (i == 1) {
+ EXT4_I(dir)->i_dir_start_lookup = block;
+ ret = bh;
+ goto cleanup_and_exit;
+ } else {
+ brelse(bh);
+ if (i < 0)
+ goto cleanup_and_exit;
+ }
+ next:
+ if (++block >= nblocks)
+ block = 0;
+ } while (block != start);
+
+ /*
+ * If the directory has grown while we were searching, then
+ * search the last part of the directory before giving up.
+ */
+ block = nblocks;
+ nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb);
+ if (block < nblocks) {
+ start = 0;
+ goto restart;
+ }
+
+cleanup_and_exit:
+ /* Clean up the read-ahead blocks */
+ for (; ra_ptr < ra_max; ra_ptr++)
+ brelse (bh_use[ra_ptr]);
+ return ret;
+}
+
+#ifdef CONFIG_EXT4_INDEX
+static struct buffer_head * ext4_dx_find_entry(struct dentry *dentry,
+ struct ext4_dir_entry_2 **res_dir, int *err)
+{
+ struct super_block * sb;
+ struct dx_hash_info hinfo;
+ u32 hash;
+ struct dx_frame frames[2], *frame;
+ struct ext4_dir_entry_2 *de, *top;
+ struct buffer_head *bh;
+ unsigned long block;
+ int retval;
+ int namelen = dentry->d_name.len;
+ const u8 *name = dentry->d_name.name;
+ struct inode *dir = dentry->d_parent->d_inode;
+
+ sb = dir->i_sb;
+ /* NFS may look up ".." - look at dx_root directory block */
+ if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
+ if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
+ return NULL;
+ } else {
+ frame = frames;
+ frame->bh = NULL; /* for dx_release() */
+ frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
+ dx_set_block(frame->at, 0); /* dx_root block is 0 */
+ }
+ hash = hinfo.hash;
+ do {
+ block = dx_get_block(frame->at);
+ if (!(bh = ext4_bread (NULL,dir, block, 0, err)))
+ goto errout;
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize -
+ EXT4_DIR_REC_LEN(0));
+ for (; de < top; de = ext4_next_entry(de))
+ if (ext4_match (namelen, name, de)) {
+ if (!ext4_check_dir_entry("ext4_find_entry",
+ dir, de, bh,
+ (block<<EXT4_BLOCK_SIZE_BITS(sb))
+ +((char *)de - bh->b_data))) {
+ brelse (bh);
+ goto errout;
+ }
+ *res_dir = de;
+ dx_release (frames);
+ return bh;
+ }
+ brelse (bh);
+ /* Check to see if we should continue to search */
+ retval = ext4_htree_next_block(dir, hash, frame,
+ frames, NULL);
+ if (retval < 0) {
+ ext4_warning(sb, __FUNCTION__,
+ "error reading index page in directory #%lu",
+ dir->i_ino);
+ *err = retval;
+ goto errout;
+ }
+ } while (retval == 1);
+
+ *err = -ENOENT;
+errout:
+ dxtrace(printk("%s not found\n", name));
+ dx_release (frames);
+ return NULL;
+}
+#endif
+
+static struct dentry *ext4_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
+{
+ struct inode * inode;
+ struct ext4_dir_entry_2 * de;
+ struct buffer_head * bh;
+
+ if (dentry->d_name.len > EXT4_NAME_LEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ bh = ext4_find_entry(dentry, &de);
+ inode = NULL;
+ if (bh) {
+ unsigned long ino = le32_to_cpu(de->inode);
+ brelse (bh);
+ if (!ext4_valid_inum(dir->i_sb, ino)) {
+ ext4_error(dir->i_sb, "ext4_lookup",
+ "bad inode number: %lu", ino);
+ inode = NULL;
+ } else
+ inode = iget(dir->i_sb, ino);
+
+ if (!inode)
+ return ERR_PTR(-EACCES);
+ }
+ return d_splice_alias(inode, dentry);
+}
+
+
+struct dentry *ext4_get_parent(struct dentry *child)
+{
+ unsigned long ino;
+ struct dentry *parent;
+ struct inode *inode;
+ struct dentry dotdot;
+ struct ext4_dir_entry_2 * de;
+ struct buffer_head *bh;
+
+ dotdot.d_name.name = "..";
+ dotdot.d_name.len = 2;
+ dotdot.d_parent = child; /* confusing, isn't it! */
+
+ bh = ext4_find_entry(&dotdot, &de);
+ inode = NULL;
+ if (!bh)
+ return ERR_PTR(-ENOENT);
+ ino = le32_to_cpu(de->inode);
+ brelse(bh);
+
+ if (!ext4_valid_inum(child->d_inode->i_sb, ino)) {
+ ext4_error(child->d_inode->i_sb, "ext4_get_parent",
+ "bad inode number: %lu", ino);
+ inode = NULL;
+ } else
+ inode = iget(child->d_inode->i_sb, ino);
+
+ if (!inode)
+ return ERR_PTR(-EACCES);
+
+ parent = d_alloc_anon(inode);
+ if (!parent) {
+ iput(inode);
+ parent = ERR_PTR(-ENOMEM);
+ }
+ return parent;
+}
+
+#define S_SHIFT 12
+static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = {
+ [S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE,
+ [S_IFDIR >> S_SHIFT] = EXT4_FT_DIR,
+ [S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV,
+ [S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV,
+ [S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO,
+ [S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK,
+ [S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK,
+};
+
+static inline void ext4_set_de_type(struct super_block *sb,
+ struct ext4_dir_entry_2 *de,
+ umode_t mode) {
+ if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE))
+ de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
+}
+
+#ifdef CONFIG_EXT4_INDEX
+static struct ext4_dir_entry_2 *
+dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
+{
+ unsigned rec_len = 0;
+
+ while (count--) {
+ struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) (from + map->offs);
+ rec_len = EXT4_DIR_REC_LEN(de->name_len);
+ memcpy (to, de, rec_len);
+ ((struct ext4_dir_entry_2 *) to)->rec_len =
+ cpu_to_le16(rec_len);
+ de->inode = 0;
+ map++;
+ to += rec_len;
+ }
+ return (struct ext4_dir_entry_2 *) (to - rec_len);
+}
+
+static struct ext4_dir_entry_2* dx_pack_dirents(char *base, int size)
+{
+ struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base;
+ unsigned rec_len = 0;
+
+ prev = to = de;
+ while ((char*)de < base + size) {
+ next = (struct ext4_dir_entry_2 *) ((char *) de +
+ le16_to_cpu(de->rec_len));
+ if (de->inode && de->name_len) {
+ rec_len = EXT4_DIR_REC_LEN(de->name_len);
+ if (de > to)
+ memmove(to, de, rec_len);
+ to->rec_len = cpu_to_le16(rec_len);
+ prev = to;
+ to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
+ }
+ de = next;
+ }
+ return prev;
+}
+
+static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
+ struct buffer_head **bh,struct dx_frame *frame,
+ struct dx_hash_info *hinfo, int *error)
+{
+ unsigned blocksize = dir->i_sb->s_blocksize;
+ unsigned count, continued;
+ struct buffer_head *bh2;
+ u32 newblock;
+ u32 hash2;
+ struct dx_map_entry *map;
+ char *data1 = (*bh)->b_data, *data2;
+ unsigned split;
+ struct ext4_dir_entry_2 *de = NULL, *de2;
+ int err;
+
+ bh2 = ext4_append (handle, dir, &newblock, error);
+ if (!(bh2)) {
+ brelse(*bh);
+ *bh = NULL;
+ goto errout;
+ }
+
+ BUFFER_TRACE(*bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, *bh);
+ if (err) {
+ journal_error:
+ brelse(*bh);
+ brelse(bh2);
+ *bh = NULL;
+ ext4_std_error(dir->i_sb, err);
+ goto errout;
+ }
+ BUFFER_TRACE(frame->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, frame->bh);
+ if (err)
+ goto journal_error;
+
+ data2 = bh2->b_data;
+
+ /* create map in the end of data2 block */
+ map = (struct dx_map_entry *) (data2 + blocksize);
+ count = dx_make_map ((struct ext4_dir_entry_2 *) data1,
+ blocksize, hinfo, map);
+ map -= count;
+ split = count/2; // need to adjust to actual middle
+ dx_sort_map (map, count);
+ hash2 = map[split].hash;
+ continued = hash2 == map[split - 1].hash;
+ dxtrace(printk("Split block %i at %x, %i/%i\n",
+ dx_get_block(frame->at), hash2, split, count-split));
+
+ /* Fancy dance to stay within two buffers */
+ de2 = dx_move_dirents(data1, data2, map + split, count - split);
+ de = dx_pack_dirents(data1,blocksize);
+ de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
+ de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
+ dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
+ dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
+
+ /* Which block gets the new entry? */
+ if (hinfo->hash >= hash2)
+ {
+ swap(*bh, bh2);
+ de = de2;
+ }
+ dx_insert_block (frame, hash2 + continued, newblock);
+ err = ext4_journal_dirty_metadata (handle, bh2);
+ if (err)
+ goto journal_error;
+ err = ext4_journal_dirty_metadata (handle, frame->bh);
+ if (err)
+ goto journal_error;
+ brelse (bh2);
+ dxtrace(dx_show_index ("frame", frame->entries));
+errout:
+ return de;
+}
+#endif
+
+
+/*
+ * Add a new entry into a directory (leaf) block. If de is non-NULL,
+ * it points to a directory entry which is guaranteed to be large
+ * enough for new directory entry. If de is NULL, then
+ * add_dirent_to_buf will attempt search the directory block for
+ * space. It will return -ENOSPC if no space is available, and -EIO
+ * and -EEXIST if directory entry already exists.
+ *
+ * NOTE! bh is NOT released in the case where ENOSPC is returned. In
+ * all other cases bh is released.
+ */
+static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
+ struct inode *inode, struct ext4_dir_entry_2 *de,
+ struct buffer_head * bh)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+ unsigned long offset = 0;
+ unsigned short reclen;
+ int nlen, rlen, err;
+ char *top;
+
+ reclen = EXT4_DIR_REC_LEN(namelen);
+ if (!de) {
+ de = (struct ext4_dir_entry_2 *)bh->b_data;
+ top = bh->b_data + dir->i_sb->s_blocksize - reclen;
+ while ((char *) de <= top) {
+ if (!ext4_check_dir_entry("ext4_add_entry", dir, de,
+ bh, offset)) {
+ brelse (bh);
+ return -EIO;
+ }
+ if (ext4_match (namelen, name, de)) {
+ brelse (bh);
+ return -EEXIST;
+ }
+ nlen = EXT4_DIR_REC_LEN(de->name_len);
+ rlen = le16_to_cpu(de->rec_len);
+ if ((de->inode? rlen - nlen: rlen) >= reclen)
+ break;
+ de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
+ offset += rlen;
+ }
+ if ((char *) de > top)
+ return -ENOSPC;
+ }
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err) {
+ ext4_std_error(dir->i_sb, err);
+ brelse(bh);
+ return err;
+ }
+
+ /* By now the buffer is marked for journaling */
+ nlen = EXT4_DIR_REC_LEN(de->name_len);
+ rlen = le16_to_cpu(de->rec_len);
+ if (de->inode) {
+ struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
+ de1->rec_len = cpu_to_le16(rlen - nlen);
+ de->rec_len = cpu_to_le16(nlen);
+ de = de1;
+ }
+ de->file_type = EXT4_FT_UNKNOWN;
+ if (inode) {
+ de->inode = cpu_to_le32(inode->i_ino);
+ ext4_set_de_type(dir->i_sb, de, inode->i_mode);
+ } else
+ de->inode = 0;
+ de->name_len = namelen;
+ memcpy (de->name, name, namelen);
+ /*
+ * XXX shouldn't update any times until successful
+ * completion of syscall, but too many callers depend
+ * on this.
+ *
+ * XXX similarly, too many callers depend on
+ * ext4_new_inode() setting the times, but error
+ * recovery deletes the inode, so the worst that can
+ * happen is that the times are slightly out of date
+ * and/or different from the directory change time.
+ */
+ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+ ext4_update_dx_flag(dir);
+ dir->i_version++;
+ ext4_mark_inode_dirty(handle, dir);
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ err = ext4_journal_dirty_metadata(handle, bh);
+ if (err)
+ ext4_std_error(dir->i_sb, err);
+ brelse(bh);
+ return 0;
+}
+
+#ifdef CONFIG_EXT4_INDEX
+/*
+ * This converts a one block unindexed directory to a 3 block indexed
+ * directory, and adds the dentry to the indexed directory.
+ */
+static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
+ struct inode *inode, struct buffer_head *bh)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
+ const char *name = dentry->d_name.name;
+ int namelen = dentry->d_name.len;
+ struct buffer_head *bh2;
+ struct dx_root *root;
+ struct dx_frame frames[2], *frame;
+ struct dx_entry *entries;
+ struct ext4_dir_entry_2 *de, *de2;
+ char *data1, *top;
+ unsigned len;
+ int retval;
+ unsigned blocksize;
+ struct dx_hash_info hinfo;
+ u32 block;
+ struct fake_dirent *fde;
+
+ blocksize = dir->i_sb->s_blocksize;
+ dxtrace(printk("Creating index\n"));
+ retval = ext4_journal_get_write_access(handle, bh);
+ if (retval) {
+ ext4_std_error(dir->i_sb, retval);
+ brelse(bh);
+ return retval;
+ }
+ root = (struct dx_root *) bh->b_data;
+
+ bh2 = ext4_append (handle, dir, &block, &retval);
+ if (!(bh2)) {
+ brelse(bh);
+ return retval;
+ }
+ EXT4_I(dir)->i_flags |= EXT4_INDEX_FL;
+ data1 = bh2->b_data;
+
+ /* The 0th block becomes the root, move the dirents out */
+ fde = &root->dotdot;
+ de = (struct ext4_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
+ len = ((char *) root) + blocksize - (char *) de;
+ memcpy (data1, de, len);
+ de = (struct ext4_dir_entry_2 *) data1;
+ top = data1 + len;
+ while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
+ de = de2;
+ de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
+ /* Initialize the root; the dot dirents already exist */
+ de = (struct ext4_dir_entry_2 *) (&root->dotdot);
+ de->rec_len = cpu_to_le16(blocksize - EXT4_DIR_REC_LEN(2));
+ memset (&root->info, 0, sizeof(root->info));
+ root->info.info_length = sizeof(root->info);
+ root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
+ entries = root->entries;
+ dx_set_block (entries, 1);
+ dx_set_count (entries, 1);
+ dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));
+
+ /* Initialize as for dx_probe */
+ hinfo.hash_version = root->info.hash_version;
+ hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed;
+ ext4fs_dirhash(name, namelen, &hinfo);
+ frame = frames;
+ frame->entries = entries;
+ frame->at = entries;
+ frame->bh = bh;
+ bh = bh2;
+ de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
+ dx_release (frames);
+ if (!(de))
+ return retval;
+
+ return add_dirent_to_buf(handle, dentry, inode, de, bh);
+}
+#endif
+
+/*
+ * ext4_add_entry()
+ *
+ * adds a file entry to the specified directory, using the same
+ * semantics as ext4_find_entry(). It returns NULL if it failed.
+ *
+ * NOTE!! The inode part of 'de' is left at 0 - which means you
+ * may not sleep between calling this and putting something into
+ * the entry, as someone else might have used it while you slept.
+ */
+static int ext4_add_entry (handle_t *handle, struct dentry *dentry,
+ struct inode *inode)
+{
+ struct inode *dir = dentry->d_parent->d_inode;
+ unsigned long offset;
+ struct buffer_head * bh;
+ struct ext4_dir_entry_2 *de;
+ struct super_block * sb;
+ int retval;
+#ifdef CONFIG_EXT4_INDEX
+ int dx_fallback=0;
+#endif
+ unsigned blocksize;
+ u32 block, blocks;
+
+ sb = dir->i_sb;
+ blocksize = sb->s_blocksize;
+ if (!dentry->d_name.len)
+ return -EINVAL;
+#ifdef CONFIG_EXT4_INDEX
+ if (is_dx(dir)) {
+ retval = ext4_dx_add_entry(handle, dentry, inode);
+ if (!retval || (retval != ERR_BAD_DX_DIR))
+ return retval;
+ EXT4_I(dir)->i_flags &= ~EXT4_INDEX_FL;
+ dx_fallback++;
+ ext4_mark_inode_dirty(handle, dir);
+ }
+#endif
+ blocks = dir->i_size >> sb->s_blocksize_bits;
+ for (block = 0, offset = 0; block < blocks; block++) {
+ bh = ext4_bread(handle, dir, block, 0, &retval);
+ if(!bh)
+ return retval;
+ retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
+ if (retval != -ENOSPC)
+ return retval;
+
+#ifdef CONFIG_EXT4_INDEX
+ if (blocks == 1 && !dx_fallback &&
+ EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX))
+ return make_indexed_dir(handle, dentry, inode, bh);
+#endif
+ brelse(bh);
+ }
+ bh = ext4_append(handle, dir, &block, &retval);
+ if (!bh)
+ return retval;
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ de->inode = 0;
+ de->rec_len = cpu_to_le16(blocksize);
+ return add_dirent_to_buf(handle, dentry, inode, de, bh);
+}
+
+#ifdef CONFIG_EXT4_INDEX
+/*
+ * Returns 0 for success, or a negative error value
+ */
+static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
+ struct inode *inode)
+{
+ struct dx_frame frames[2], *frame;
+ struct dx_entry *entries, *at;
+ struct dx_hash_info hinfo;
+ struct buffer_head * bh;
+ struct inode *dir = dentry->d_parent->d_inode;
+ struct super_block * sb = dir->i_sb;
+ struct ext4_dir_entry_2 *de;
+ int err;
+
+ frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
+ if (!frame)
+ return err;
+ entries = frame->entries;
+ at = frame->at;
+
+ if (!(bh = ext4_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
+ goto cleanup;
+
+ BUFFER_TRACE(bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err)
+ goto journal_error;
+
+ err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
+ if (err != -ENOSPC) {
+ bh = NULL;
+ goto cleanup;
+ }
+
+ /* Block full, should compress but for now just split */
+ dxtrace(printk("using %u of %u node entries\n",
+ dx_get_count(entries), dx_get_limit(entries)));
+ /* Need to split index? */
+ if (dx_get_count(entries) == dx_get_limit(entries)) {
+ u32 newblock;
+ unsigned icount = dx_get_count(entries);
+ int levels = frame - frames;
+ struct dx_entry *entries2;
+ struct dx_node *node2;
+ struct buffer_head *bh2;
+
+ if (levels && (dx_get_count(frames->entries) ==
+ dx_get_limit(frames->entries))) {
+ ext4_warning(sb, __FUNCTION__,
+ "Directory index full!");
+ err = -ENOSPC;
+ goto cleanup;
+ }
+ bh2 = ext4_append (handle, dir, &newblock, &err);
+ if (!(bh2))
+ goto cleanup;
+ node2 = (struct dx_node *)(bh2->b_data);
+ entries2 = node2->entries;
+ node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
+ node2->fake.inode = 0;
+ BUFFER_TRACE(frame->bh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, frame->bh);
+ if (err)
+ goto journal_error;
+ if (levels) {
+ unsigned icount1 = icount/2, icount2 = icount - icount1;
+ unsigned hash2 = dx_get_hash(entries + icount1);
+ dxtrace(printk("Split index %i/%i\n", icount1, icount2));
+
+ BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
+ err = ext4_journal_get_write_access(handle,
+ frames[0].bh);
+ if (err)
+ goto journal_error;
+
+ memcpy ((char *) entries2, (char *) (entries + icount1),
+ icount2 * sizeof(struct dx_entry));
+ dx_set_count (entries, icount1);
+ dx_set_count (entries2, icount2);
+ dx_set_limit (entries2, dx_node_limit(dir));
+
+ /* Which index block gets the new entry? */
+ if (at - entries >= icount1) {
+ frame->at = at = at - entries - icount1 + entries2;
+ frame->entries = entries = entries2;
+ swap(frame->bh, bh2);
+ }
+ dx_insert_block (frames + 0, hash2, newblock);
+ dxtrace(dx_show_index ("node", frames[1].entries));
+ dxtrace(dx_show_index ("node",
+ ((struct dx_node *) bh2->b_data)->entries));
+ err = ext4_journal_dirty_metadata(handle, bh2);
+ if (err)
+ goto journal_error;
+ brelse (bh2);
+ } else {
+ dxtrace(printk("Creating second level index...\n"));
+ memcpy((char *) entries2, (char *) entries,
+ icount * sizeof(struct dx_entry));
+ dx_set_limit(entries2, dx_node_limit(dir));
+
+ /* Set up root */
+ dx_set_count(entries, 1);
+ dx_set_block(entries + 0, newblock);
+ ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;
+
+ /* Add new access path frame */
+ frame = frames + 1;
+ frame->at = at = at - entries + entries2;
+ frame->entries = entries = entries2;
+ frame->bh = bh2;
+ err = ext4_journal_get_write_access(handle,
+ frame->bh);
+ if (err)
+ goto journal_error;
+ }
+ ext4_journal_dirty_metadata(handle, frames[0].bh);
+ }
+ de = do_split(handle, dir, &bh, frame, &hinfo, &err);
+ if (!de)
+ goto cleanup;
+ err = add_dirent_to_buf(handle, dentry, inode, de, bh);
+ bh = NULL;
+ goto cleanup;
+
+journal_error:
+ ext4_std_error(dir->i_sb, err);
+cleanup:
+ if (bh)
+ brelse(bh);
+ dx_release(frames);
+ return err;
+}
+#endif
+
+/*
+ * ext4_delete_entry deletes a directory entry by merging it with the
+ * previous entry
+ */
+static int ext4_delete_entry (handle_t *handle,
+ struct inode * dir,
+ struct ext4_dir_entry_2 * de_del,
+ struct buffer_head * bh)
+{
+ struct ext4_dir_entry_2 * de, * pde;
+ int i;
+
+ i = 0;
+ pde = NULL;
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ while (i < bh->b_size) {
+ if (!ext4_check_dir_entry("ext4_delete_entry", dir, de, bh, i))
+ return -EIO;
+ if (de == de_del) {
+ BUFFER_TRACE(bh, "get_write_access");
+ ext4_journal_get_write_access(handle, bh);
+ if (pde)
+ pde->rec_len =
+ cpu_to_le16(le16_to_cpu(pde->rec_len) +
+ le16_to_cpu(de->rec_len));
+ else
+ de->inode = 0;
+ dir->i_version++;
+ BUFFER_TRACE(bh, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, bh);
+ return 0;
+ }
+ i += le16_to_cpu(de->rec_len);
+ pde = de;
+ de = (struct ext4_dir_entry_2 *)
+ ((char *) de + le16_to_cpu(de->rec_len));
+ }
+ return -ENOENT;
+}
+
+/*
+ * ext4_mark_inode_dirty is somewhat expensive, so unlike ext2 we
+ * do not perform it in these functions. We perform it at the call site,
+ * if it is needed.
+ */
+static inline void ext4_inc_count(handle_t *handle, struct inode *inode)
+{
+ inc_nlink(inode);
+}
+
+static inline void ext4_dec_count(handle_t *handle, struct inode *inode)
+{
+ drop_nlink(inode);
+}
+
+static int ext4_add_nondir(handle_t *handle,
+ struct dentry *dentry, struct inode *inode)
+{
+ int err = ext4_add_entry(handle, dentry, inode);
+ if (!err) {
+ ext4_mark_inode_dirty(handle, inode);
+ d_instantiate(dentry, inode);
+ return 0;
+ }
+ ext4_dec_count(handle, inode);
+ iput(inode);
+ return err;
+}
+
+/*
+ * By the time this is called, we already have created
+ * the directory cache entry for the new file, but it
+ * is so far negative - it has no inode.
+ *
+ * If the create succeeds, we fill in the inode information
+ * with d_instantiate().
+ */
+static int ext4_create (struct inode * dir, struct dentry * dentry, int mode,
+ struct nameidata *nd)
+{
+ handle_t *handle;
+ struct inode * inode;
+ int err, retries = 0;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
+ 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode = ext4_new_inode (handle, dir, mode);
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ inode->i_op = &ext4_file_inode_operations;
+ inode->i_fop = &ext4_file_operations;
+ ext4_set_aops(inode);
+ err = ext4_add_nondir(handle, dentry, inode);
+ }
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+static int ext4_mknod (struct inode * dir, struct dentry *dentry,
+ int mode, dev_t rdev)
+{
+ handle_t *handle;
+ struct inode *inode;
+ int err, retries = 0;
+
+ if (!new_valid_dev(rdev))
+ return -EINVAL;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
+ 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode = ext4_new_inode (handle, dir, mode);
+ err = PTR_ERR(inode);
+ if (!IS_ERR(inode)) {
+ init_special_inode(inode, inode->i_mode, rdev);
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ inode->i_op = &ext4_special_inode_operations;
+#endif
+ err = ext4_add_nondir(handle, dentry, inode);
+ }
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+static int ext4_mkdir(struct inode * dir, struct dentry * dentry, int mode)
+{
+ handle_t *handle;
+ struct inode * inode;
+ struct buffer_head * dir_block;
+ struct ext4_dir_entry_2 * de;
+ int err, retries = 0;
+
+ if (dir->i_nlink >= EXT4_LINK_MAX)
+ return -EMLINK;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 +
+ 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode = ext4_new_inode (handle, dir, S_IFDIR | mode);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_stop;
+
+ inode->i_op = &ext4_dir_inode_operations;
+ inode->i_fop = &ext4_dir_operations;
+ inode->i_size = EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
+ dir_block = ext4_bread (handle, inode, 0, 1, &err);
+ if (!dir_block) {
+ drop_nlink(inode); /* is this nlink == 0? */
+ ext4_mark_inode_dirty(handle, inode);
+ iput (inode);
+ goto out_stop;
+ }
+ BUFFER_TRACE(dir_block, "get_write_access");
+ ext4_journal_get_write_access(handle, dir_block);
+ de = (struct ext4_dir_entry_2 *) dir_block->b_data;
+ de->inode = cpu_to_le32(inode->i_ino);
+ de->name_len = 1;
+ de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(de->name_len));
+ strcpy (de->name, ".");
+ ext4_set_de_type(dir->i_sb, de, S_IFDIR);
+ de = (struct ext4_dir_entry_2 *)
+ ((char *) de + le16_to_cpu(de->rec_len));
+ de->inode = cpu_to_le32(dir->i_ino);
+ de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT4_DIR_REC_LEN(1));
+ de->name_len = 2;
+ strcpy (de->name, "..");
+ ext4_set_de_type(dir->i_sb, de, S_IFDIR);
+ inode->i_nlink = 2;
+ BUFFER_TRACE(dir_block, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, dir_block);
+ brelse (dir_block);
+ ext4_mark_inode_dirty(handle, inode);
+ err = ext4_add_entry (handle, dentry, inode);
+ if (err) {
+ inode->i_nlink = 0;
+ ext4_mark_inode_dirty(handle, inode);
+ iput (inode);
+ goto out_stop;
+ }
+ inc_nlink(dir);
+ ext4_update_dx_flag(dir);
+ ext4_mark_inode_dirty(handle, dir);
+ d_instantiate(dentry, inode);
+out_stop:
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+static int empty_dir (struct inode * inode)
+{
+ unsigned long offset;
+ struct buffer_head * bh;
+ struct ext4_dir_entry_2 * de, * de1;
+ struct super_block * sb;
+ int err = 0;
+
+ sb = inode->i_sb;
+ if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) ||
+ !(bh = ext4_bread (NULL, inode, 0, 0, &err))) {
+ if (err)
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "error %d reading directory #%lu offset 0",
+ err, inode->i_ino);
+ else
+ ext4_warning(inode->i_sb, __FUNCTION__,
+ "bad directory (dir #%lu) - no data block",
+ inode->i_ino);
+ return 1;
+ }
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ de1 = (struct ext4_dir_entry_2 *)
+ ((char *) de + le16_to_cpu(de->rec_len));
+ if (le32_to_cpu(de->inode) != inode->i_ino ||
+ !le32_to_cpu(de1->inode) ||
+ strcmp (".", de->name) ||
+ strcmp ("..", de1->name)) {
+ ext4_warning (inode->i_sb, "empty_dir",
+ "bad directory (dir #%lu) - no `.' or `..'",
+ inode->i_ino);
+ brelse (bh);
+ return 1;
+ }
+ offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
+ de = (struct ext4_dir_entry_2 *)
+ ((char *) de1 + le16_to_cpu(de1->rec_len));
+ while (offset < inode->i_size ) {
+ if (!bh ||
+ (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
+ err = 0;
+ brelse (bh);
+ bh = ext4_bread (NULL, inode,
+ offset >> EXT4_BLOCK_SIZE_BITS(sb), 0, &err);
+ if (!bh) {
+ if (err)
+ ext4_error(sb, __FUNCTION__,
+ "error %d reading directory"
+ " #%lu offset %lu",
+ err, inode->i_ino, offset);
+ offset += sb->s_blocksize;
+ continue;
+ }
+ de = (struct ext4_dir_entry_2 *) bh->b_data;
+ }
+ if (!ext4_check_dir_entry("empty_dir", inode, de, bh, offset)) {
+ de = (struct ext4_dir_entry_2 *)(bh->b_data +
+ sb->s_blocksize);
+ offset = (offset | (sb->s_blocksize - 1)) + 1;
+ continue;
+ }
+ if (le32_to_cpu(de->inode)) {
+ brelse (bh);
+ return 0;
+ }
+ offset += le16_to_cpu(de->rec_len);
+ de = (struct ext4_dir_entry_2 *)
+ ((char *) de + le16_to_cpu(de->rec_len));
+ }
+ brelse (bh);
+ return 1;
+}
+
+/* ext4_orphan_add() links an unlinked or truncated inode into a list of
+ * such inodes, starting at the superblock, in case we crash before the
+ * file is closed/deleted, or in case the inode truncate spans multiple
+ * transactions and the last transaction is not recovered after a crash.
+ *
+ * At filesystem recovery time, we walk this list deleting unlinked
+ * inodes and truncating linked inodes in ext4_orphan_cleanup().
+ */
+int ext4_orphan_add(handle_t *handle, struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct ext4_iloc iloc;
+ int err = 0, rc;
+
+ lock_super(sb);
+ if (!list_empty(&EXT4_I(inode)->i_orphan))
+ goto out_unlock;
+
+ /* Orphan handling is only valid for files with data blocks
+ * being truncated, or files being unlinked. */
+
+ /* @@@ FIXME: Observation from aviro:
+ * I think I can trigger J_ASSERT in ext4_orphan_add(). We block
+ * here (on lock_super()), so race with ext4_link() which might bump
+ * ->i_nlink. For, say it, character device. Not a regular file,
+ * not a directory, not a symlink and ->i_nlink > 0.
+ */
+ J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+ S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
+
+ BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
+ if (err)
+ goto out_unlock;
+
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err)
+ goto out_unlock;
+
+ /* Insert this inode at the head of the on-disk orphan list... */
+ NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan);
+ EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
+ err = ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
+ rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
+ if (!err)
+ err = rc;
+
+ /* Only add to the head of the in-memory list if all the
+ * previous operations succeeded. If the orphan_add is going to
+ * fail (possibly taking the journal offline), we can't risk
+ * leaving the inode on the orphan list: stray orphan-list
+ * entries can cause panics at unmount time.
+ *
+ * This is safe: on error we're going to ignore the orphan list
+ * anyway on the next recovery. */
+ if (!err)
+ list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
+
+ jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
+ jbd_debug(4, "orphan inode %lu will point to %d\n",
+ inode->i_ino, NEXT_ORPHAN(inode));
+out_unlock:
+ unlock_super(sb);
+ ext4_std_error(inode->i_sb, err);
+ return err;
+}
+
+/*
+ * ext4_orphan_del() removes an unlinked or truncated inode from the list
+ * of such inodes stored on disk, because it is finally being cleaned up.
+ */
+int ext4_orphan_del(handle_t *handle, struct inode *inode)
+{
+ struct list_head *prev;
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_sb_info *sbi;
+ unsigned long ino_next;
+ struct ext4_iloc iloc;
+ int err = 0;
+
+ lock_super(inode->i_sb);
+ if (list_empty(&ei->i_orphan)) {
+ unlock_super(inode->i_sb);
+ return 0;
+ }
+
+ ino_next = NEXT_ORPHAN(inode);
+ prev = ei->i_orphan.prev;
+ sbi = EXT4_SB(inode->i_sb);
+
+ jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
+
+ list_del_init(&ei->i_orphan);
+
+ /* If we're on an error path, we may not have a valid
+ * transaction handle with which to update the orphan list on
+ * disk, but we still need to remove the inode from the linked
+ * list in memory. */
+ if (!handle)
+ goto out;
+
+ err = ext4_reserve_inode_write(handle, inode, &iloc);
+ if (err)
+ goto out_err;
+
+ if (prev == &sbi->s_orphan) {
+ jbd_debug(4, "superblock will point to %lu\n", ino_next);
+ BUFFER_TRACE(sbi->s_sbh, "get_write_access");
+ err = ext4_journal_get_write_access(handle, sbi->s_sbh);
+ if (err)
+ goto out_brelse;
+ sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
+ err = ext4_journal_dirty_metadata(handle, sbi->s_sbh);
+ } else {
+ struct ext4_iloc iloc2;
+ struct inode *i_prev =
+ &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
+
+ jbd_debug(4, "orphan inode %lu will point to %lu\n",
+ i_prev->i_ino, ino_next);
+ err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
+ if (err)
+ goto out_brelse;
+ NEXT_ORPHAN(i_prev) = ino_next;
+ err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
+ }
+ if (err)
+ goto out_brelse;
+ NEXT_ORPHAN(inode) = 0;
+ err = ext4_mark_iloc_dirty(handle, inode, &iloc);
+
+out_err:
+ ext4_std_error(inode->i_sb, err);
+out:
+ unlock_super(inode->i_sb);
+ return err;
+
+out_brelse:
+ brelse(iloc.bh);
+ goto out_err;
+}
+
+static int ext4_rmdir (struct inode * dir, struct dentry *dentry)
+{
+ int retval;
+ struct inode * inode;
+ struct buffer_head * bh;
+ struct ext4_dir_entry_2 * de;
+ handle_t *handle;
+
+ /* Initialize quotas before so that eventual writes go in
+ * separate transaction */
+ DQUOT_INIT(dentry->d_inode);
+ handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ retval = -ENOENT;
+ bh = ext4_find_entry (dentry, &de);
+ if (!bh)
+ goto end_rmdir;
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode = dentry->d_inode;
+
+ retval = -EIO;
+ if (le32_to_cpu(de->inode) != inode->i_ino)
+ goto end_rmdir;
+
+ retval = -ENOTEMPTY;
+ if (!empty_dir (inode))
+ goto end_rmdir;
+
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ if (retval)
+ goto end_rmdir;
+ if (inode->i_nlink != 2)
+ ext4_warning (inode->i_sb, "ext4_rmdir",
+ "empty directory has nlink!=2 (%d)",
+ inode->i_nlink);
+ inode->i_version++;
+ clear_nlink(inode);
+ /* There's no need to set i_disksize: the fact that i_nlink is
+ * zero will ensure that the right thing happens during any
+ * recovery. */
+ inode->i_size = 0;
+ ext4_orphan_add(handle, inode);
+ inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
+ ext4_mark_inode_dirty(handle, inode);
+ drop_nlink(dir);
+ ext4_update_dx_flag(dir);
+ ext4_mark_inode_dirty(handle, dir);
+
+end_rmdir:
+ ext4_journal_stop(handle);
+ brelse (bh);
+ return retval;
+}
+
+static int ext4_unlink(struct inode * dir, struct dentry *dentry)
+{
+ int retval;
+ struct inode * inode;
+ struct buffer_head * bh;
+ struct ext4_dir_entry_2 * de;
+ handle_t *handle;
+
+ /* Initialize quotas before so that eventual writes go
+ * in separate transaction */
+ DQUOT_INIT(dentry->d_inode);
+ handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ retval = -ENOENT;
+ bh = ext4_find_entry (dentry, &de);
+ if (!bh)
+ goto end_unlink;
+
+ inode = dentry->d_inode;
+
+ retval = -EIO;
+ if (le32_to_cpu(de->inode) != inode->i_ino)
+ goto end_unlink;
+
+ if (!inode->i_nlink) {
+ ext4_warning (inode->i_sb, "ext4_unlink",
+ "Deleting nonexistent file (%lu), %d",
+ inode->i_ino, inode->i_nlink);
+ inode->i_nlink = 1;
+ }
+ retval = ext4_delete_entry(handle, dir, de, bh);
+ if (retval)
+ goto end_unlink;
+ dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
+ ext4_update_dx_flag(dir);
+ ext4_mark_inode_dirty(handle, dir);
+ drop_nlink(inode);
+ if (!inode->i_nlink)
+ ext4_orphan_add(handle, inode);
+ inode->i_ctime = dir->i_ctime;
+ ext4_mark_inode_dirty(handle, inode);
+ retval = 0;
+
+end_unlink:
+ ext4_journal_stop(handle);
+ brelse (bh);
+ return retval;
+}
+
+static int ext4_symlink (struct inode * dir,
+ struct dentry *dentry, const char * symname)
+{
+ handle_t *handle;
+ struct inode * inode;
+ int l, err, retries = 0;
+
+ l = strlen(symname)+1;
+ if (l > dir->i_sb->s_blocksize)
+ return -ENAMETOOLONG;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 5 +
+ 2*EXT4_QUOTA_INIT_BLOCKS(dir->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode = ext4_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_stop;
+
+ if (l > sizeof (EXT4_I(inode)->i_data)) {
+ inode->i_op = &ext4_symlink_inode_operations;
+ ext4_set_aops(inode);
+ /*
+ * page_symlink() calls into ext4_prepare/commit_write.
+ * We have a transaction open. All is sweetness. It also sets
+ * i_size in generic_commit_write().
+ */
+ err = __page_symlink(inode, symname, l,
+ mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
+ if (err) {
+ ext4_dec_count(handle, inode);
+ ext4_mark_inode_dirty(handle, inode);
+ iput (inode);
+ goto out_stop;
+ }
+ } else {
+ inode->i_op = &ext4_fast_symlink_inode_operations;
+ memcpy((char*)&EXT4_I(inode)->i_data,symname,l);
+ inode->i_size = l-1;
+ }
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ err = ext4_add_nondir(handle, dentry, inode);
+out_stop:
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+static int ext4_link (struct dentry * old_dentry,
+ struct inode * dir, struct dentry *dentry)
+{
+ handle_t *handle;
+ struct inode *inode = old_dentry->d_inode;
+ int err, retries = 0;
+
+ if (inode->i_nlink >= EXT4_LINK_MAX)
+ return -EMLINK;
+
+retry:
+ handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ handle->h_sync = 1;
+
+ inode->i_ctime = CURRENT_TIME_SEC;
+ ext4_inc_count(handle, inode);
+ atomic_inc(&inode->i_count);
+
+ err = ext4_add_nondir(handle, dentry, inode);
+ ext4_journal_stop(handle);
+ if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries))
+ goto retry;
+ return err;
+}
+
+#define PARENT_INO(buffer) \
+ ((struct ext4_dir_entry_2 *) ((char *) buffer + \
+ le16_to_cpu(((struct ext4_dir_entry_2 *) buffer)->rec_len)))->inode
+
+/*
+ * Anybody can rename anything with this: the permission checks are left to the
+ * higher-level routines.
+ */
+static int ext4_rename (struct inode * old_dir, struct dentry *old_dentry,
+ struct inode * new_dir,struct dentry *new_dentry)
+{
+ handle_t *handle;
+ struct inode * old_inode, * new_inode;
+ struct buffer_head * old_bh, * new_bh, * dir_bh;
+ struct ext4_dir_entry_2 * old_de, * new_de;
+ int retval;
+
+ old_bh = new_bh = dir_bh = NULL;
+
+ /* Initialize quotas before so that eventual writes go
+ * in separate transaction */
+ if (new_dentry->d_inode)
+ DQUOT_INIT(new_dentry->d_inode);
+ handle = ext4_journal_start(old_dir, 2 *
+ EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) +
+ EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
+ handle->h_sync = 1;
+
+ old_bh = ext4_find_entry (old_dentry, &old_de);
+ /*
+ * Check for inode number is _not_ due to possible IO errors.
+ * We might rmdir the source, keep it as pwd of some process
+ * and merrily kill the link to whatever was created under the
+ * same name. Goodbye sticky bit ;-<
+ */
+ old_inode = old_dentry->d_inode;
+ retval = -ENOENT;
+ if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
+ goto end_rename;
+
+ new_inode = new_dentry->d_inode;
+ new_bh = ext4_find_entry (new_dentry, &new_de);
+ if (new_bh) {
+ if (!new_inode) {
+ brelse (new_bh);
+ new_bh = NULL;
+ }
+ }
+ if (S_ISDIR(old_inode->i_mode)) {
+ if (new_inode) {
+ retval = -ENOTEMPTY;
+ if (!empty_dir (new_inode))
+ goto end_rename;
+ }
+ retval = -EIO;
+ dir_bh = ext4_bread (handle, old_inode, 0, 0, &retval);
+ if (!dir_bh)
+ goto end_rename;
+ if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
+ goto end_rename;
+ retval = -EMLINK;
+ if (!new_inode && new_dir!=old_dir &&
+ new_dir->i_nlink >= EXT4_LINK_MAX)
+ goto end_rename;
+ }
+ if (!new_bh) {
+ retval = ext4_add_entry (handle, new_dentry, old_inode);
+ if (retval)
+ goto end_rename;
+ } else {
+ BUFFER_TRACE(new_bh, "get write access");
+ ext4_journal_get_write_access(handle, new_bh);
+ new_de->inode = cpu_to_le32(old_inode->i_ino);
+ if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
+ EXT4_FEATURE_INCOMPAT_FILETYPE))
+ new_de->file_type = old_de->file_type;
+ new_dir->i_version++;
+ BUFFER_TRACE(new_bh, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, new_bh);
+ brelse(new_bh);
+ new_bh = NULL;
+ }
+
+ /*
+ * Like most other Unix systems, set the ctime for inodes on a
+ * rename.
+ */
+ old_inode->i_ctime = CURRENT_TIME_SEC;
+ ext4_mark_inode_dirty(handle, old_inode);
+
+ /*
+ * ok, that's it
+ */
+ if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
+ old_de->name_len != old_dentry->d_name.len ||
+ strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
+ (retval = ext4_delete_entry(handle, old_dir,
+ old_de, old_bh)) == -ENOENT) {
+ /* old_de could have moved from under us during htree split, so
+ * make sure that we are deleting the right entry. We might
+ * also be pointing to a stale entry in the unused part of
+ * old_bh so just checking inum and the name isn't enough. */
+ struct buffer_head *old_bh2;
+ struct ext4_dir_entry_2 *old_de2;
+
+ old_bh2 = ext4_find_entry(old_dentry, &old_de2);
+ if (old_bh2) {
+ retval = ext4_delete_entry(handle, old_dir,
+ old_de2, old_bh2);
+ brelse(old_bh2);
+ }
+ }
+ if (retval) {
+ ext4_warning(old_dir->i_sb, "ext4_rename",
+ "Deleting old file (%lu), %d, error=%d",
+ old_dir->i_ino, old_dir->i_nlink, retval);
+ }
+
+ if (new_inode) {
+ drop_nlink(new_inode);
+ new_inode->i_ctime = CURRENT_TIME_SEC;
+ }
+ old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
+ ext4_update_dx_flag(old_dir);
+ if (dir_bh) {
+ BUFFER_TRACE(dir_bh, "get_write_access");
+ ext4_journal_get_write_access(handle, dir_bh);
+ PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
+ BUFFER_TRACE(dir_bh, "call ext4_journal_dirty_metadata");
+ ext4_journal_dirty_metadata(handle, dir_bh);
+ drop_nlink(old_dir);
+ if (new_inode) {
+ drop_nlink(new_inode);
+ } else {
+ inc_nlink(new_dir);
+ ext4_update_dx_flag(new_dir);
+ ext4_mark_inode_dirty(handle, new_dir);
+ }
+ }
+ ext4_mark_inode_dirty(handle, old_dir);
+ if (new_inode) {
+ ext4_mark_inode_dirty(handle, new_inode);
+ if (!new_inode->i_nlink)
+ ext4_orphan_add(handle, new_inode);
+ }
+ retval = 0;
+
+end_rename:
+ brelse (dir_bh);
+ brelse (old_bh);
+ brelse (new_bh);
+ ext4_journal_stop(handle);
+ return retval;
+}
+
+/*
+ * directories can handle most operations...
+ */
+struct inode_operations ext4_dir_inode_operations = {
+ .create = ext4_create,
+ .lookup = ext4_lookup,
+ .link = ext4_link,
+ .unlink = ext4_unlink,
+ .symlink = ext4_symlink,
+ .mkdir = ext4_mkdir,
+ .rmdir = ext4_rmdir,
+ .mknod = ext4_mknod,
+ .rename = ext4_rename,
+ .setattr = ext4_setattr,
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = ext4_listxattr,
+ .removexattr = generic_removexattr,
+#endif
+ .permission = ext4_permission,
+};
+
+struct inode_operations ext4_special_inode_operations = {
+ .setattr = ext4_setattr,
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = ext4_listxattr,
+ .removexattr = generic_removexattr,
+#endif
+ .permission = ext4_permission,
+};
diff --git a/fs/ext4/namei.h b/fs/ext4/namei.h
new file mode 100644
index 000000000000..5e4dfff36a00
--- /dev/null
+++ b/fs/ext4/namei.h
@@ -0,0 +1,8 @@
+/* linux/fs/ext4/namei.h
+ *
+ * Copyright (C) 2005 Simtec Electronics
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+*/
+
+extern struct dentry *ext4_get_parent(struct dentry *child);
diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c
new file mode 100644
index 000000000000..1e9578052cd3
--- /dev/null
+++ b/fs/ext4/resize.c
@@ -0,0 +1,1045 @@
+/*
+ * linux/fs/ext4/resize.c
+ *
+ * Support for resizing an ext4 filesystem while it is mounted.
+ *
+ * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com>
+ *
+ * This could probably be made into a module, because it is not often in use.
+ */
+
+
+#define EXT4FS_DEBUG
+
+#include <linux/sched.h>
+#include <linux/smp_lock.h>
+#include <linux/ext4_jbd2.h>
+
+#include <linux/errno.h>
+#include <linux/slab.h>
+
+
+#define outside(b, first, last) ((b) < (first) || (b) >= (last))
+#define inside(b, first, last) ((b) >= (first) && (b) < (last))
+
+static int verify_group_input(struct super_block *sb,
+ struct ext4_new_group_data *input)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+ ext4_fsblk_t start = ext4_blocks_count(es);
+ ext4_fsblk_t end = start + input->blocks_count;
+ unsigned group = input->group;
+ ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group;
+ unsigned overhead = ext4_bg_has_super(sb, group) ?
+ (1 + ext4_bg_num_gdb(sb, group) +
+ le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
+ ext4_fsblk_t metaend = start + overhead;
+ struct buffer_head *bh = NULL;
+ ext4_grpblk_t free_blocks_count, offset;
+ int err = -EINVAL;
+
+ input->free_blocks_count = free_blocks_count =
+ input->blocks_count - 2 - overhead - sbi->s_itb_per_group;
+
+ if (test_opt(sb, DEBUG))
+ printk(KERN_DEBUG "EXT4-fs: adding %s group %u: %u blocks "
+ "(%d free, %u reserved)\n",
+ ext4_bg_has_super(sb, input->group) ? "normal" :
+ "no-super", input->group, input->blocks_count,
+ free_blocks_count, input->reserved_blocks);
+
+ ext4_get_group_no_and_offset(sb, start, NULL, &offset);
+ if (group != sbi->s_groups_count)
+ ext4_warning(sb, __FUNCTION__,
+ "Cannot add at group %u (only %lu groups)",
+ input->group, sbi->s_groups_count);
+ else if (offset != 0)
+ ext4_warning(sb, __FUNCTION__, "Last group not full");
+ else if (input->reserved_blocks > input->blocks_count / 5)
+ ext4_warning(sb, __FUNCTION__, "Reserved blocks too high (%u)",
+ input->reserved_blocks);
+ else if (free_blocks_count < 0)
+ ext4_warning(sb, __FUNCTION__, "Bad blocks count %u",
+ input->blocks_count);
+ else if (!(bh = sb_bread(sb, end - 1)))
+ ext4_warning(sb, __FUNCTION__,
+ "Cannot read last block (%llu)",
+ end - 1);
+ else if (outside(input->block_bitmap, start, end))
+ ext4_warning(sb, __FUNCTION__,
+ "Block bitmap not in group (block %llu)",
+ input->block_bitmap);
+ else if (outside(input->inode_bitmap, start, end))
+ ext4_warning(sb, __FUNCTION__,
+ "Inode bitmap not in group (block %llu)",
+ input->inode_bitmap);
+ else if (outside(input->inode_table, start, end) ||
+ outside(itend - 1, start, end))
+ ext4_warning(sb, __FUNCTION__,
+ "Inode table not in group (blocks %llu-%llu)",
+ input->inode_table, itend - 1);
+ else if (input->inode_bitmap == input->block_bitmap)
+ ext4_warning(sb, __FUNCTION__,
+ "Block bitmap same as inode bitmap (%llu)",
+ input->block_bitmap);
+ else if (inside(input->block_bitmap, input->inode_table, itend))
+ ext4_warning(sb, __FUNCTION__,
+ "Block bitmap (%llu) in inode table (%llu-%llu)",
+ input->block_bitmap, input->inode_table, itend-1);
+ else if (inside(input->inode_bitmap, input->inode_table, itend))
+ ext4_warning(sb, __FUNCTION__,
+ "Inode bitmap (%llu) in inode table (%llu-%llu)",
+ input->inode_bitmap, input->inode_table, itend-1);
+ else if (inside(input->block_bitmap, start, metaend))
+ ext4_warning(sb, __FUNCTION__,
+ "Block bitmap (%llu) in GDT table"
+ " (%llu-%llu)",
+ input->block_bitmap, start, metaend - 1);
+ else if (inside(input->inode_bitmap, start, metaend))
+ ext4_warning(sb, __FUNCTION__,
+ "Inode bitmap (%llu) in GDT table"
+ " (%llu-%llu)",
+ input->inode_bitmap, start, metaend - 1);
+ else if (inside(input->inode_table, start, metaend) ||
+ inside(itend - 1, start, metaend))
+ ext4_warning(sb, __FUNCTION__,
+ "Inode table (%llu-%llu) overlaps"
+ "GDT table (%llu-%llu)",
+ input->inode_table, itend - 1, start, metaend - 1);
+ else
+ err = 0;
+ brelse(bh);
+
+ return err;
+}
+
+static struct buffer_head *bclean(handle_t *handle, struct super_block *sb,
+ ext4_fsblk_t blk)
+{
+ struct buffer_head *bh;
+ int err;
+
+ bh = sb_getblk(sb, blk);
+ if (!bh)
+ return ERR_PTR(-EIO);
+ if ((err = ext4_journal_get_write_access(handle, bh))) {
+ brelse(bh);
+ bh = ERR_PTR(err);
+ } else {
+ lock_buffer(bh);
+ memset(bh->b_data, 0, sb->s_blocksize);
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+ }
+
+ return bh;
+}
+
+/*
+ * To avoid calling the atomic setbit hundreds or thousands of times, we only
+ * need to use it within a single byte (to ensure we get endianness right).
+ * We can use memset for the rest of the bitmap as there are no other users.
+ */
+static void mark_bitmap_end(int start_bit, int end_bit, char *bitmap)
+{
+ int i;
+
+ if (start_bit >= end_bit)
+ return;
+
+ ext4_debug("mark end bits +%d through +%d used\n", start_bit, end_bit);
+ for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
+ ext4_set_bit(i, bitmap);
+ if (i < end_bit)
+ memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
+}
+
+/*
+ * Set up the block and inode bitmaps, and the inode table for the new group.
+ * This doesn't need to be part of the main transaction, since we are only
+ * changing blocks outside the actual filesystem. We still do journaling to
+ * ensure the recovery is correct in case of a failure just after resize.
+ * If any part of this fails, we simply abort the resize.
+ */
+static int setup_new_group_blocks(struct super_block *sb,
+ struct ext4_new_group_data *input)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ ext4_fsblk_t start = ext4_group_first_block_no(sb, input->group);
+ int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
+ le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0;
+ unsigned long gdblocks = ext4_bg_num_gdb(sb, input->group);
+ struct buffer_head *bh;
+ handle_t *handle;
+ ext4_fsblk_t block;
+ ext4_grpblk_t bit;
+ int i;
+ int err = 0, err2;
+
+ handle = ext4_journal_start_sb(sb, reserved_gdb + gdblocks +
+ 2 + sbi->s_itb_per_group);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ lock_super(sb);
+ if (input->group != sbi->s_groups_count) {
+ err = -EBUSY;
+ goto exit_journal;
+ }
+
+ if (IS_ERR(bh = bclean(handle, sb, input->block_bitmap))) {
+ err = PTR_ERR(bh);
+ goto exit_journal;
+ }
+
+ if (ext4_bg_has_super(sb, input->group)) {
+ ext4_debug("mark backup superblock %#04lx (+0)\n", start);
+ ext4_set_bit(0, bh->b_data);
+ }
+
+ /* Copy all of the GDT blocks into the backup in this group */
+ for (i = 0, bit = 1, block = start + 1;
+ i < gdblocks; i++, block++, bit++) {
+ struct buffer_head *gdb;
+
+ ext4_debug("update backup group %#04lx (+%d)\n", block, bit);
+
+ gdb = sb_getblk(sb, block);
+ if (!gdb) {
+ err = -EIO;
+ goto exit_bh;
+ }
+ if ((err = ext4_journal_get_write_access(handle, gdb))) {
+ brelse(gdb);
+ goto exit_bh;
+ }
+ lock_buffer(bh);
+ memcpy(gdb->b_data, sbi->s_group_desc[i]->b_data, bh->b_size);
+ set_buffer_uptodate(gdb);
+ unlock_buffer(bh);
+ ext4_journal_dirty_metadata(handle, gdb);
+ ext4_set_bit(bit, bh->b_data);
+ brelse(gdb);
+ }
+
+ /* Zero out all of the reserved backup group descriptor table blocks */
+ for (i = 0, bit = gdblocks + 1, block = start + bit;
+ i < reserved_gdb; i++, block++, bit++) {
+ struct buffer_head *gdb;
+
+ ext4_debug("clear reserved block %#04lx (+%d)\n", block, bit);
+
+ if (IS_ERR(gdb = bclean(handle, sb, block))) {
+ err = PTR_ERR(bh);
+ goto exit_bh;
+ }
+ ext4_journal_dirty_metadata(handle, gdb);
+ ext4_set_bit(bit, bh->b_data);
+ brelse(gdb);
+ }
+ ext4_debug("mark block bitmap %#04x (+%ld)\n", input->block_bitmap,
+ input->block_bitmap - start);
+ ext4_set_bit(input->block_bitmap - start, bh->b_data);
+ ext4_debug("mark inode bitmap %#04x (+%ld)\n", input->inode_bitmap,
+ input->inode_bitmap - start);
+ ext4_set_bit(input->inode_bitmap - start, bh->b_data);
+
+ /* Zero out all of the inode table blocks */
+ for (i = 0, block = input->inode_table, bit = block - start;
+ i < sbi->s_itb_per_group; i++, bit++, block++) {
+ struct buffer_head *it;
+
+ ext4_debug("clear inode block %#04lx (+%d)\n", block, bit);
+ if (IS_ERR(it = bclean(handle, sb, block))) {
+ err = PTR_ERR(it);
+ goto exit_bh;
+ }
+ ext4_journal_dirty_metadata(handle, it);
+ brelse(it);
+ ext4_set_bit(bit, bh->b_data);
+ }
+ mark_bitmap_end(input->blocks_count, EXT4_BLOCKS_PER_GROUP(sb),
+ bh->b_data);
+ ext4_journal_dirty_metadata(handle, bh);
+ brelse(bh);
+
+ /* Mark unused entries in inode bitmap used */
+ ext4_debug("clear inode bitmap %#04x (+%ld)\n",
+ input->inode_bitmap, input->inode_bitmap - start);
+ if (IS_ERR(bh = bclean(handle, sb, input->inode_bitmap))) {
+ err = PTR_ERR(bh);
+ goto exit_journal;
+ }
+
+ mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), EXT4_BLOCKS_PER_GROUP(sb),
+ bh->b_data);
+ ext4_journal_dirty_metadata(handle, bh);
+exit_bh:
+ brelse(bh);
+
+exit_journal:
+ unlock_super(sb);
+ if ((err2 = ext4_journal_stop(handle)) && !err)
+ err = err2;
+
+ return err;
+}
+
+
+/*
+ * Iterate through the groups which hold BACKUP superblock/GDT copies in an
+ * ext4 filesystem. The counters should be initialized to 1, 5, and 7 before
+ * calling this for the first time. In a sparse filesystem it will be the
+ * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
+ * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
+ */
+static unsigned ext4_list_backups(struct super_block *sb, unsigned *three,
+ unsigned *five, unsigned *seven)
+{
+ unsigned *min = three;
+ int mult = 3;
+ unsigned ret;
+
+ if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
+ ret = *min;
+ *min += 1;
+ return ret;
+ }
+
+ if (*five < *min) {
+ min = five;
+ mult = 5;
+ }
+ if (*seven < *min) {
+ min = seven;
+ mult = 7;
+ }
+
+ ret = *min;
+ *min *= mult;
+
+ return ret;
+}
+
+/*
+ * Check that all of the backup GDT blocks are held in the primary GDT block.
+ * It is assumed that they are stored in group order. Returns the number of
+ * groups in current filesystem that have BACKUPS, or -ve error code.
+ */
+static int verify_reserved_gdb(struct super_block *sb,
+ struct buffer_head *primary)
+{
+ const ext4_fsblk_t blk = primary->b_blocknr;
+ const unsigned long end = EXT4_SB(sb)->s_groups_count;
+ unsigned three = 1;
+ unsigned five = 5;
+ unsigned seven = 7;
+ unsigned grp;
+ __le32 *p = (__le32 *)primary->b_data;
+ int gdbackups = 0;
+
+ while ((grp = ext4_list_backups(sb, &three, &five, &seven)) < end) {
+ if (le32_to_cpu(*p++) !=
+ grp * EXT4_BLOCKS_PER_GROUP(sb) + blk){
+ ext4_warning(sb, __FUNCTION__,
+ "reserved GDT %llu"
+ " missing grp %d (%llu)",
+ blk, grp,
+ grp *
+ (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
+ blk);
+ return -EINVAL;
+ }
+ if (++gdbackups > EXT4_ADDR_PER_BLOCK(sb))
+ return -EFBIG;
+ }
+
+ return gdbackups;
+}
+
+/*
+ * Called when we need to bring a reserved group descriptor table block into
+ * use from the resize inode. The primary copy of the new GDT block currently
+ * is an indirect block (under the double indirect block in the resize inode).
+ * The new backup GDT blocks will be stored as leaf blocks in this indirect
+ * block, in group order. Even though we know all the block numbers we need,
+ * we check to ensure that the resize inode has actually reserved these blocks.
+ *
+ * Don't need to update the block bitmaps because the blocks are still in use.
+ *
+ * We get all of the error cases out of the way, so that we are sure to not
+ * fail once we start modifying the data on disk, because JBD has no rollback.
+ */
+static int add_new_gdb(handle_t *handle, struct inode *inode,
+ struct ext4_new_group_data *input,
+ struct buffer_head **primary)
+{
+ struct super_block *sb = inode->i_sb;
+ struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+ unsigned long gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
+ ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num;
+ struct buffer_head **o_group_desc, **n_group_desc;
+ struct buffer_head *dind;
+ int gdbackups;
+ struct ext4_iloc iloc;
+ __le32 *data;
+ int err;
+
+ if (test_opt(sb, DEBUG))
+ printk(KERN_DEBUG
+ "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n",
+ gdb_num);
+
+ /*
+ * If we are not using the primary superblock/GDT copy don't resize,
+ * because the user tools have no way of handling this. Probably a
+ * bad time to do it anyways.
+ */
+ if (EXT4_SB(sb)->s_sbh->b_blocknr !=
+ le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) {
+ ext4_warning(sb, __FUNCTION__,
+ "won't resize using backup superblock at %llu",
+ (unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr);
+ return -EPERM;
+ }
+
+ *primary = sb_bread(sb, gdblock);
+ if (!*primary)
+ return -EIO;
+
+ if ((gdbackups = verify_reserved_gdb(sb, *primary)) < 0) {
+ err = gdbackups;
+ goto exit_bh;
+ }
+
+ data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
+ dind = sb_bread(sb, le32_to_cpu(*data));
+ if (!dind) {
+ err = -EIO;
+ goto exit_bh;
+ }
+
+ data = (__le32 *)dind->b_data;
+ if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) {
+ ext4_warning(sb, __FUNCTION__,
+ "new group %u GDT block %llu not reserved",
+ input->group, gdblock);
+ err = -EINVAL;
+ goto exit_dind;
+ }
+
+ if ((err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh)))
+ goto exit_dind;
+
+ if ((err = ext4_journal_get_write_access(handle, *primary)))
+ goto exit_sbh;
+
+ if ((err = ext4_journal_get_write_access(handle, dind)))
+ goto exit_primary;
+
+ /* ext4_reserve_inode_write() gets a reference on the iloc */
+ if ((err = ext4_reserve_inode_write(handle, inode, &iloc)))
+ goto exit_dindj;
+
+ n_group_desc = kmalloc((gdb_num + 1) * sizeof(struct buffer_head *),
+ GFP_KERNEL);
+ if (!n_group_desc) {
+ err = -ENOMEM;
+ ext4_warning (sb, __FUNCTION__,
+ "not enough memory for %lu groups", gdb_num + 1);
+ goto exit_inode;
+ }
+
+ /*
+ * Finally, we have all of the possible failures behind us...
+ *
+ * Remove new GDT block from inode double-indirect block and clear out
+ * the new GDT block for use (which also "frees" the backup GDT blocks
+ * from the reserved inode). We don't need to change the bitmaps for
+ * these blocks, because they are marked as in-use from being in the
+ * reserved inode, and will become GDT blocks (primary and backup).
+ */
+ data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)] = 0;
+ ext4_journal_dirty_metadata(handle, dind);
+ brelse(dind);
+ inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9;
+ ext4_mark_iloc_dirty(handle, inode, &iloc);
+ memset((*primary)->b_data, 0, sb->s_blocksize);
+ ext4_journal_dirty_metadata(handle, *primary);
+
+ o_group_desc = EXT4_SB(sb)->s_group_desc;
+ memcpy(n_group_desc, o_group_desc,
+ EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
+ n_group_desc[gdb_num] = *primary;
+ EXT4_SB(sb)->s_group_desc = n_group_desc;
+ EXT4_SB(sb)->s_gdb_count++;
+ kfree(o_group_desc);
+
+ es->s_reserved_gdt_blocks =
+ cpu_to_le16(le16_to_cpu(es->s_reserved_gdt_blocks) - 1);
+ ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
+
+ return 0;
+
+exit_inode:
+ //ext4_journal_release_buffer(handle, iloc.bh);
+ brelse(iloc.bh);
+exit_dindj:
+ //ext4_journal_release_buffer(handle, dind);
+exit_primary:
+ //ext4_journal_release_buffer(handle, *primary);
+exit_sbh:
+ //ext4_journal_release_buffer(handle, *primary);
+exit_dind:
+ brelse(dind);
+exit_bh:
+ brelse(*primary);
+
+ ext4_debug("leaving with error %d\n", err);
+ return err;
+}
+
+/*
+ * Called when we are adding a new group which has a backup copy of each of
+ * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
+ * We need to add these reserved backup GDT blocks to the resize inode, so
+ * that they are kept for future resizing and not allocated to files.
+ *
+ * Each reserved backup GDT block will go into a different indirect block.
+ * The indirect blocks are actually the primary reserved GDT blocks,
+ * so we know in advance what their block numbers are. We only get the
+ * double-indirect block to verify it is pointing to the primary reserved
+ * GDT blocks so we don't overwrite a data block by accident. The reserved
+ * backup GDT blocks are stored in their reserved primary GDT block.
+ */
+static int reserve_backup_gdb(handle_t *handle, struct inode *inode,
+ struct ext4_new_group_data *input)
+{
+ struct super_block *sb = inode->i_sb;
+ int reserved_gdb =le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks);
+ struct buffer_head **primary;
+ struct buffer_head *dind;
+ struct ext4_iloc iloc;
+ ext4_fsblk_t blk;
+ __le32 *data, *end;
+ int gdbackups = 0;
+ int res, i;
+ int err;
+
+ primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_KERNEL);
+ if (!primary)
+ return -ENOMEM;
+
+ data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
+ dind = sb_bread(sb, le32_to_cpu(*data));
+ if (!dind) {
+ err = -EIO;
+ goto exit_free;
+ }
+
+ blk = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + EXT4_SB(sb)->s_gdb_count;
+ data = (__le32 *)dind->b_data + EXT4_SB(sb)->s_gdb_count;
+ end = (__le32 *)dind->b_data + EXT4_ADDR_PER_BLOCK(sb);
+
+ /* Get each reserved primary GDT block and verify it holds backups */
+ for (res = 0; res < reserved_gdb; res++, blk++) {
+ if (le32_to_cpu(*data) != blk) {
+ ext4_warning(sb, __FUNCTION__,
+ "reserved block %llu"
+ " not at offset %ld",
+ blk,
+ (long)(data - (__le32 *)dind->b_data));
+ err = -EINVAL;
+ goto exit_bh;
+ }
+ primary[res] = sb_bread(sb, blk);
+ if (!primary[res]) {
+ err = -EIO;
+ goto exit_bh;
+ }
+ if ((gdbackups = verify_reserved_gdb(sb, primary[res])) < 0) {
+ brelse(primary[res]);
+ err = gdbackups;
+ goto exit_bh;
+ }
+ if (++data >= end)
+ data = (__le32 *)dind->b_data;
+ }
+
+ for (i = 0; i < reserved_gdb; i++) {
+ if ((err = ext4_journal_get_write_access(handle, primary[i]))) {
+ /*
+ int j;
+ for (j = 0; j < i; j++)
+ ext4_journal_release_buffer(handle, primary[j]);
+ */
+ goto exit_bh;
+ }
+ }
+
+ if ((err = ext4_reserve_inode_write(handle, inode, &iloc)))
+ goto exit_bh;
+
+ /*
+ * Finally we can add each of the reserved backup GDT blocks from
+ * the new group to its reserved primary GDT block.
+ */
+ blk = input->group * EXT4_BLOCKS_PER_GROUP(sb);
+ for (i = 0; i < reserved_gdb; i++) {
+ int err2;
+ data = (__le32 *)primary[i]->b_data;
+ /* printk("reserving backup %lu[%u] = %lu\n",
+ primary[i]->b_blocknr, gdbackups,
+ blk + primary[i]->b_blocknr); */
+ data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr);
+ err2 = ext4_journal_dirty_metadata(handle, primary[i]);
+ if (!err)
+ err = err2;
+ }
+ inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9;
+ ext4_mark_iloc_dirty(handle, inode, &iloc);
+
+exit_bh:
+ while (--res >= 0)
+ brelse(primary[res]);
+ brelse(dind);
+
+exit_free:
+ kfree(primary);
+
+ return err;
+}
+
+/*
+ * Update the backup copies of the ext4 metadata. These don't need to be part
+ * of the main resize transaction, because e2fsck will re-write them if there
+ * is a problem (basically only OOM will cause a problem). However, we
+ * _should_ update the backups if possible, in case the primary gets trashed
+ * for some reason and we need to run e2fsck from a backup superblock. The
+ * important part is that the new block and inode counts are in the backup
+ * superblocks, and the location of the new group metadata in the GDT backups.
+ *
+ * We do not need lock_super() for this, because these blocks are not
+ * otherwise touched by the filesystem code when it is mounted. We don't
+ * need to worry about last changing from sbi->s_groups_count, because the
+ * worst that can happen is that we do not copy the full number of backups
+ * at this time. The resize which changed s_groups_count will backup again.
+ */
+static void update_backups(struct super_block *sb,
+ int blk_off, char *data, int size)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ const unsigned long last = sbi->s_groups_count;
+ const int bpg = EXT4_BLOCKS_PER_GROUP(sb);
+ unsigned three = 1;
+ unsigned five = 5;
+ unsigned seven = 7;
+ unsigned group;
+ int rest = sb->s_blocksize - size;
+ handle_t *handle;
+ int err = 0, err2;
+
+ handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
+ if (IS_ERR(handle)) {
+ group = 1;
+ err = PTR_ERR(handle);
+ goto exit_err;
+ }
+
+ while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) {
+ struct buffer_head *bh;
+
+ /* Out of journal space, and can't get more - abort - so sad */
+ if (handle->h_buffer_credits == 0 &&
+ ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA) &&
+ (err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA)))
+ break;
+
+ bh = sb_getblk(sb, group * bpg + blk_off);
+ if (!bh) {
+ err = -EIO;
+ break;
+ }
+ ext4_debug("update metadata backup %#04lx\n",
+ (unsigned long)bh->b_blocknr);
+ if ((err = ext4_journal_get_write_access(handle, bh)))
+ break;
+ lock_buffer(bh);
+ memcpy(bh->b_data, data, size);
+ if (rest)
+ memset(bh->b_data + size, 0, rest);
+ set_buffer_uptodate(bh);
+ unlock_buffer(bh);
+ ext4_journal_dirty_metadata(handle, bh);
+ brelse(bh);
+ }
+ if ((err2 = ext4_journal_stop(handle)) && !err)
+ err = err2;
+
+ /*
+ * Ugh! Need to have e2fsck write the backup copies. It is too
+ * late to revert the resize, we shouldn't fail just because of
+ * the backup copies (they are only needed in case of corruption).
+ *
+ * However, if we got here we have a journal problem too, so we
+ * can't really start a transaction to mark the superblock.
+ * Chicken out and just set the flag on the hope it will be written
+ * to disk, and if not - we will simply wait until next fsck.
+ */
+exit_err:
+ if (err) {
+ ext4_warning(sb, __FUNCTION__,
+ "can't update backup for group %d (err %d), "
+ "forcing fsck on next reboot", group, err);
+ sbi->s_mount_state &= ~EXT4_VALID_FS;
+ sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
+ mark_buffer_dirty(sbi->s_sbh);
+ }
+}
+
+/* Add group descriptor data to an existing or new group descriptor block.
+ * Ensure we handle all possible error conditions _before_ we start modifying
+ * the filesystem, because we cannot abort the transaction and not have it
+ * write the data to disk.
+ *
+ * If we are on a GDT block boundary, we need to get the reserved GDT block.
+ * Otherwise, we may need to add backup GDT blocks for a sparse group.
+ *
+ * We only need to hold the superblock lock while we are actually adding
+ * in the new group's counts to the superblock. Prior to that we have
+ * not really "added" the group at all. We re-check that we are still
+ * adding in the last group in case things have changed since verifying.
+ */
+int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+ int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
+ le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
+ struct buffer_head *primary = NULL;
+ struct ext4_group_desc *gdp;
+ struct inode *inode = NULL;
+ handle_t *handle;
+ int gdb_off, gdb_num;
+ int err, err2;
+
+ gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
+ gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb);
+
+ if (gdb_off == 0 && !EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
+ ext4_warning(sb, __FUNCTION__,
+ "Can't resize non-sparse filesystem further");
+ return -EPERM;
+ }
+
+ if (ext4_blocks_count(es) + input->blocks_count <
+ ext4_blocks_count(es)) {
+ ext4_warning(sb, __FUNCTION__, "blocks_count overflow\n");
+ return -EINVAL;
+ }
+
+ if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) <
+ le32_to_cpu(es->s_inodes_count)) {
+ ext4_warning(sb, __FUNCTION__, "inodes_count overflow\n");
+ return -EINVAL;
+ }
+
+ if (reserved_gdb || gdb_off == 0) {
+ if (!EXT4_HAS_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_COMPAT_RESIZE_INODE)){
+ ext4_warning(sb, __FUNCTION__,
+ "No reserved GDT blocks, can't resize");
+ return -EPERM;
+ }
+ inode = iget(sb, EXT4_RESIZE_INO);
+ if (!inode || is_bad_inode(inode)) {
+ ext4_warning(sb, __FUNCTION__,
+ "Error opening resize inode");
+ iput(inode);
+ return -ENOENT;
+ }
+ }
+
+ if ((err = verify_group_input(sb, input)))
+ goto exit_put;
+
+ if ((err = setup_new_group_blocks(sb, input)))
+ goto exit_put;
+
+ /*
+ * We will always be modifying at least the superblock and a GDT
+ * block. If we are adding a group past the last current GDT block,
+ * we will also modify the inode and the dindirect block. If we
+ * are adding a group with superblock/GDT backups we will also
+ * modify each of the reserved GDT dindirect blocks.
+ */
+ handle = ext4_journal_start_sb(sb,
+ ext4_bg_has_super(sb, input->group) ?
+ 3 + reserved_gdb : 4);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ goto exit_put;
+ }
+
+ lock_super(sb);
+ if (input->group != sbi->s_groups_count) {
+ ext4_warning(sb, __FUNCTION__,
+ "multiple resizers run on filesystem!");
+ err = -EBUSY;
+ goto exit_journal;
+ }
+
+ if ((err = ext4_journal_get_write_access(handle, sbi->s_sbh)))
+ goto exit_journal;
+
+ /*
+ * We will only either add reserved group blocks to a backup group
+ * or remove reserved blocks for the first group in a new group block.
+ * Doing both would be mean more complex code, and sane people don't
+ * use non-sparse filesystems anymore. This is already checked above.
+ */
+ if (gdb_off) {
+ primary = sbi->s_group_desc[gdb_num];
+ if ((err = ext4_journal_get_write_access(handle, primary)))
+ goto exit_journal;
+
+ if (reserved_gdb && ext4_bg_num_gdb(sb, input->group) &&
+ (err = reserve_backup_gdb(handle, inode, input)))
+ goto exit_journal;
+ } else if ((err = add_new_gdb(handle, inode, input, &primary)))
+ goto exit_journal;
+
+ /*
+ * OK, now we've set up the new group. Time to make it active.
+ *
+ * Current kernels don't lock all allocations via lock_super(),
+ * so we have to be safe wrt. concurrent accesses the group
+ * data. So we need to be careful to set all of the relevant
+ * group descriptor data etc. *before* we enable the group.
+ *
+ * The key field here is sbi->s_groups_count: as long as
+ * that retains its old value, nobody is going to access the new
+ * group.
+ *
+ * So first we update all the descriptor metadata for the new
+ * group; then we update the total disk blocks count; then we
+ * update the groups count to enable the group; then finally we
+ * update the free space counts so that the system can start
+ * using the new disk blocks.
+ */
+
+ /* Update group descriptor block for new group */
+ gdp = (struct ext4_group_desc *)primary->b_data + gdb_off;
+
+ ext4_block_bitmap_set(sb, gdp, input->block_bitmap); /* LV FIXME */
+ ext4_inode_bitmap_set(sb, gdp, input->inode_bitmap); /* LV FIXME */
+ ext4_inode_table_set(sb, gdp, input->inode_table); /* LV FIXME */
+ gdp->bg_free_blocks_count = cpu_to_le16(input->free_blocks_count);
+ gdp->bg_free_inodes_count = cpu_to_le16(EXT4_INODES_PER_GROUP(sb));
+
+ /*
+ * Make the new blocks and inodes valid next. We do this before
+ * increasing the group count so that once the group is enabled,
+ * all of its blocks and inodes are already valid.
+ *
+ * We always allocate group-by-group, then block-by-block or
+ * inode-by-inode within a group, so enabling these
+ * blocks/inodes before the group is live won't actually let us
+ * allocate the new space yet.
+ */
+ ext4_blocks_count_set(es, ext4_blocks_count(es) +
+ input->blocks_count);
+ es->s_inodes_count = cpu_to_le32(le32_to_cpu(es->s_inodes_count) +
+ EXT4_INODES_PER_GROUP(sb));
+
+ /*
+ * We need to protect s_groups_count against other CPUs seeing
+ * inconsistent state in the superblock.
+ *
+ * The precise rules we use are:
+ *
+ * * Writers of s_groups_count *must* hold lock_super
+ * AND
+ * * Writers must perform a smp_wmb() after updating all dependent
+ * data and before modifying the groups count
+ *
+ * * Readers must hold lock_super() over the access
+ * OR
+ * * Readers must perform an smp_rmb() after reading the groups count
+ * and before reading any dependent data.
+ *
+ * NB. These rules can be relaxed when checking the group count
+ * while freeing data, as we can only allocate from a block
+ * group after serialising against the group count, and we can
+ * only then free after serialising in turn against that
+ * allocation.
+ */
+ smp_wmb();
+
+ /* Update the global fs size fields */
+ sbi->s_groups_count++;
+
+ ext4_journal_dirty_metadata(handle, primary);
+
+ /* Update the reserved block counts only once the new group is
+ * active. */
+ ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) +
+ input->reserved_blocks);
+
+ /* Update the free space counts */
+ percpu_counter_mod(&sbi->s_freeblocks_counter,
+ input->free_blocks_count);
+ percpu_counter_mod(&sbi->s_freeinodes_counter,
+ EXT4_INODES_PER_GROUP(sb));
+
+ ext4_journal_dirty_metadata(handle, sbi->s_sbh);
+ sb->s_dirt = 1;
+
+exit_journal:
+ unlock_super(sb);
+ if ((err2 = ext4_journal_stop(handle)) && !err)
+ err = err2;
+ if (!err) {
+ update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
+ sizeof(struct ext4_super_block));
+ update_backups(sb, primary->b_blocknr, primary->b_data,
+ primary->b_size);
+ }
+exit_put:
+ iput(inode);
+ return err;
+} /* ext4_group_add */
+
+/* Extend the filesystem to the new number of blocks specified. This entry
+ * point is only used to extend the current filesystem to the end of the last
+ * existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
+ * for emergencies (because it has no dependencies on reserved blocks).
+ *
+ * If we _really_ wanted, we could use default values to call ext4_group_add()
+ * allow the "remount" trick to work for arbitrary resizing, assuming enough
+ * GDT blocks are reserved to grow to the desired size.
+ */
+int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
+ ext4_fsblk_t n_blocks_count)
+{
+ ext4_fsblk_t o_blocks_count;
+ unsigned long o_groups_count;
+ ext4_grpblk_t last;
+ ext4_grpblk_t add;
+ struct buffer_head * bh;
+ handle_t *handle;
+ int err;
+ unsigned long freed_blocks;
+
+ /* We don't need to worry about locking wrt other resizers just
+ * yet: we're going to revalidate es->s_blocks_count after
+ * taking lock_super() below. */
+ o_blocks_count = ext4_blocks_count(es);
+ o_groups_count = EXT4_SB(sb)->s_groups_count;
+
+ if (test_opt(sb, DEBUG))
+ printk(KERN_DEBUG "EXT4-fs: extending last group from %llu uto %llu blocks\n",
+ o_blocks_count, n_blocks_count);
+
+ if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
+ return 0;
+
+ if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
+ printk(KERN_ERR "EXT4-fs: filesystem on %s:"
+ " too large to resize to %llu blocks safely\n",
+ sb->s_id, n_blocks_count);
+ if (sizeof(sector_t) < 8)
+ ext4_warning(sb, __FUNCTION__,
+ "CONFIG_LBD not enabled\n");
+ return -EINVAL;
+ }
+
+ if (n_blocks_count < o_blocks_count) {
+ ext4_warning(sb, __FUNCTION__,
+ "can't shrink FS - resize aborted");
+ return -EBUSY;
+ }
+
+ /* Handle the remaining blocks in the last group only. */
+ ext4_get_group_no_and_offset(sb, o_blocks_count, NULL, &last);
+
+ if (last == 0) {
+ ext4_warning(sb, __FUNCTION__,
+ "need to use ext2online to resize further");
+ return -EPERM;
+ }
+
+ add = EXT4_BLOCKS_PER_GROUP(sb) - last;
+
+ if (o_blocks_count + add < o_blocks_count) {
+ ext4_warning(sb, __FUNCTION__, "blocks_count overflow");
+ return -EINVAL;
+ }
+
+ if (o_blocks_count + add > n_blocks_count)
+ add = n_blocks_count - o_blocks_count;
+
+ if (o_blocks_count + add < n_blocks_count)
+ ext4_warning(sb, __FUNCTION__,
+ "will only finish group (%llu"
+ " blocks, %u new)",
+ o_blocks_count + add, add);
+
+ /* See if the device is actually as big as what was requested */
+ bh = sb_bread(sb, o_blocks_count + add -1);
+ if (!bh) {
+ ext4_warning(sb, __FUNCTION__,
+ "can't read last block, resize aborted");
+ return -ENOSPC;
+ }
+ brelse(bh);
+
+ /* We will update the superblock, one block bitmap, and
+ * one group descriptor via ext4_free_blocks().
+ */
+ handle = ext4_journal_start_sb(sb, 3);
+ if (IS_ERR(handle)) {
+ err = PTR_ERR(handle);
+ ext4_warning(sb, __FUNCTION__, "error %d on journal start",err);
+ goto exit_put;
+ }
+
+ lock_super(sb);
+ if (o_blocks_count != ext4_blocks_count(es)) {
+ ext4_warning(sb, __FUNCTION__,
+ "multiple resizers run on filesystem!");
+ unlock_super(sb);
+ err = -EBUSY;
+ goto exit_put;
+ }
+
+ if ((err = ext4_journal_get_write_access(handle,
+ EXT4_SB(sb)->s_sbh))) {
+ ext4_warning(sb, __FUNCTION__,
+ "error %d on journal write access", err);
+ unlock_super(sb);
+ ext4_journal_stop(handle);
+ goto exit_put;
+ }
+ ext4_blocks_count_set(es, o_blocks_count + add);
+ ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
+ sb->s_dirt = 1;
+ unlock_super(sb);
+ ext4_debug("freeing blocks %lu through %llu\n", o_blocks_count,
+ o_blocks_count + add);
+ ext4_free_blocks_sb(handle, sb, o_blocks_count, add, &freed_blocks);
+ ext4_debug("freed blocks %llu through %llu\n", o_blocks_count,
+ o_blocks_count + add);
+ if ((err = ext4_journal_stop(handle)))
+ goto exit_put;
+ if (test_opt(sb, DEBUG))
+ printk(KERN_DEBUG "EXT4-fs: extended group to %llu blocks\n",
+ ext4_blocks_count(es));
+ update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es,
+ sizeof(struct ext4_super_block));
+exit_put:
+ return err;
+} /* ext4_group_extend */
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
new file mode 100644
index 000000000000..b4b022aa2bc2
--- /dev/null
+++ b/fs/ext4/super.c
@@ -0,0 +1,2829 @@
+/*
+ * linux/fs/ext4/super.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/inode.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * Big-endian to little-endian byte-swapping/bitmaps by
+ * David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/parser.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <linux/vfs.h>
+#include <linux/random.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/quotaops.h>
+#include <linux/seq_file.h>
+
+#include <asm/uaccess.h>
+
+#include "xattr.h"
+#include "acl.h"
+#include "namei.h"
+
+static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
+ unsigned long journal_devnum);
+static int ext4_create_journal(struct super_block *, struct ext4_super_block *,
+ unsigned int);
+static void ext4_commit_super (struct super_block * sb,
+ struct ext4_super_block * es,
+ int sync);
+static void ext4_mark_recovery_complete(struct super_block * sb,
+ struct ext4_super_block * es);
+static void ext4_clear_journal_err(struct super_block * sb,
+ struct ext4_super_block * es);
+static int ext4_sync_fs(struct super_block *sb, int wait);
+static const char *ext4_decode_error(struct super_block * sb, int errno,
+ char nbuf[16]);
+static int ext4_remount (struct super_block * sb, int * flags, char * data);
+static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf);
+static void ext4_unlockfs(struct super_block *sb);
+static void ext4_write_super (struct super_block * sb);
+static void ext4_write_super_lockfs(struct super_block *sb);
+
+
+ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
+ struct ext4_group_desc *bg)
+{
+ return le32_to_cpu(bg->bg_block_bitmap) |
+ (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
+ (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
+}
+
+ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
+ struct ext4_group_desc *bg)
+{
+ return le32_to_cpu(bg->bg_inode_bitmap) |
+ (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
+ (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
+}
+
+ext4_fsblk_t ext4_inode_table(struct super_block *sb,
+ struct ext4_group_desc *bg)
+{
+ return le32_to_cpu(bg->bg_inode_table) |
+ (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
+ (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
+}
+
+void ext4_block_bitmap_set(struct super_block *sb,
+ struct ext4_group_desc *bg, ext4_fsblk_t blk)
+{
+ bg->bg_block_bitmap = cpu_to_le32((u32)blk);
+ if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
+ bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
+}
+
+void ext4_inode_bitmap_set(struct super_block *sb,
+ struct ext4_group_desc *bg, ext4_fsblk_t blk)
+{
+ bg->bg_inode_bitmap = cpu_to_le32((u32)blk);
+ if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
+ bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
+}
+
+void ext4_inode_table_set(struct super_block *sb,
+ struct ext4_group_desc *bg, ext4_fsblk_t blk)
+{
+ bg->bg_inode_table = cpu_to_le32((u32)blk);
+ if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
+ bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
+}
+
+/*
+ * Wrappers for jbd2_journal_start/end.
+ *
+ * The only special thing we need to do here is to make sure that all
+ * journal_end calls result in the superblock being marked dirty, so
+ * that sync() will call the filesystem's write_super callback if
+ * appropriate.
+ */
+handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
+{
+ journal_t *journal;
+
+ if (sb->s_flags & MS_RDONLY)
+ return ERR_PTR(-EROFS);
+
+ /* Special case here: if the journal has aborted behind our
+ * backs (eg. EIO in the commit thread), then we still need to
+ * take the FS itself readonly cleanly. */
+ journal = EXT4_SB(sb)->s_journal;
+ if (is_journal_aborted(journal)) {
+ ext4_abort(sb, __FUNCTION__,
+ "Detected aborted journal");
+ return ERR_PTR(-EROFS);
+ }
+
+ return jbd2_journal_start(journal, nblocks);
+}
+
+/*
+ * The only special thing we need to do here is to make sure that all
+ * jbd2_journal_stop calls result in the superblock being marked dirty, so
+ * that sync() will call the filesystem's write_super callback if
+ * appropriate.
+ */
+int __ext4_journal_stop(const char *where, handle_t *handle)
+{
+ struct super_block *sb;
+ int err;
+ int rc;
+
+ sb = handle->h_transaction->t_journal->j_private;
+ err = handle->h_err;
+ rc = jbd2_journal_stop(handle);
+
+ if (!err)
+ err = rc;
+ if (err)
+ __ext4_std_error(sb, where, err);
+ return err;
+}
+
+void ext4_journal_abort_handle(const char *caller, const char *err_fn,
+ struct buffer_head *bh, handle_t *handle, int err)
+{
+ char nbuf[16];
+ const char *errstr = ext4_decode_error(NULL, err, nbuf);
+
+ if (bh)
+ BUFFER_TRACE(bh, "abort");
+
+ if (!handle->h_err)
+ handle->h_err = err;
+
+ if (is_handle_aborted(handle))
+ return;
+
+ printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
+ caller, errstr, err_fn);
+
+ jbd2_journal_abort_handle(handle);
+}
+
+/* Deal with the reporting of failure conditions on a filesystem such as
+ * inconsistencies detected or read IO failures.
+ *
+ * On ext2, we can store the error state of the filesystem in the
+ * superblock. That is not possible on ext4, because we may have other
+ * write ordering constraints on the superblock which prevent us from
+ * writing it out straight away; and given that the journal is about to
+ * be aborted, we can't rely on the current, or future, transactions to
+ * write out the superblock safely.
+ *
+ * We'll just use the jbd2_journal_abort() error code to record an error in
+ * the journal instead. On recovery, the journal will compain about
+ * that error until we've noted it down and cleared it.
+ */
+
+static void ext4_handle_error(struct super_block *sb)
+{
+ struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+
+ EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
+ es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
+
+ if (sb->s_flags & MS_RDONLY)
+ return;
+
+ if (!test_opt (sb, ERRORS_CONT)) {
+ journal_t *journal = EXT4_SB(sb)->s_journal;
+
+ EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
+ if (journal)
+ jbd2_journal_abort(journal, -EIO);
+ }
+ if (test_opt (sb, ERRORS_RO)) {
+ printk (KERN_CRIT "Remounting filesystem read-only\n");
+ sb->s_flags |= MS_RDONLY;
+ }
+ ext4_commit_super(sb, es, 1);
+ if (test_opt(sb, ERRORS_PANIC))
+ panic("EXT4-fs (device %s): panic forced after error\n",
+ sb->s_id);
+}
+
+void ext4_error (struct super_block * sb, const char * function,
+ const char * fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
+ vprintk(fmt, args);
+ printk("\n");
+ va_end(args);
+
+ ext4_handle_error(sb);
+}
+
+static const char *ext4_decode_error(struct super_block * sb, int errno,
+ char nbuf[16])
+{
+ char *errstr = NULL;
+
+ switch (errno) {
+ case -EIO:
+ errstr = "IO failure";
+ break;
+ case -ENOMEM:
+ errstr = "Out of memory";
+ break;
+ case -EROFS:
+ if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
+ errstr = "Journal has aborted";
+ else
+ errstr = "Readonly filesystem";
+ break;
+ default:
+ /* If the caller passed in an extra buffer for unknown
+ * errors, textualise them now. Else we just return
+ * NULL. */
+ if (nbuf) {
+ /* Check for truncated error codes... */
+ if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
+ errstr = nbuf;
+ }
+ break;
+ }
+
+ return errstr;
+}
+
+/* __ext4_std_error decodes expected errors from journaling functions
+ * automatically and invokes the appropriate error response. */
+
+void __ext4_std_error (struct super_block * sb, const char * function,
+ int errno)
+{
+ char nbuf[16];
+ const char *errstr;
+
+ /* Special case: if the error is EROFS, and we're not already
+ * inside a transaction, then there's really no point in logging
+ * an error. */
+ if (errno == -EROFS && journal_current_handle() == NULL &&
+ (sb->s_flags & MS_RDONLY))
+ return;
+
+ errstr = ext4_decode_error(sb, errno, nbuf);
+ printk (KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
+ sb->s_id, function, errstr);
+
+ ext4_handle_error(sb);
+}
+
+/*
+ * ext4_abort is a much stronger failure handler than ext4_error. The
+ * abort function may be used to deal with unrecoverable failures such
+ * as journal IO errors or ENOMEM at a critical moment in log management.
+ *
+ * We unconditionally force the filesystem into an ABORT|READONLY state,
+ * unless the error response on the fs has been set to panic in which
+ * case we take the easy way out and panic immediately.
+ */
+
+void ext4_abort (struct super_block * sb, const char * function,
+ const char * fmt, ...)
+{
+ va_list args;
+
+ printk (KERN_CRIT "ext4_abort called.\n");
+
+ va_start(args, fmt);
+ printk(KERN_CRIT "EXT4-fs error (device %s): %s: ",sb->s_id, function);
+ vprintk(fmt, args);
+ printk("\n");
+ va_end(args);
+
+ if (test_opt(sb, ERRORS_PANIC))
+ panic("EXT4-fs panic from previous error\n");
+
+ if (sb->s_flags & MS_RDONLY)
+ return;
+
+ printk(KERN_CRIT "Remounting filesystem read-only\n");
+ EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
+ sb->s_flags |= MS_RDONLY;
+ EXT4_SB(sb)->s_mount_opt |= EXT4_MOUNT_ABORT;
+ jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
+}
+
+void ext4_warning (struct super_block * sb, const char * function,
+ const char * fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
+ sb->s_id, function);
+ vprintk(fmt, args);
+ printk("\n");
+ va_end(args);
+}
+
+void ext4_update_dynamic_rev(struct super_block *sb)
+{
+ struct ext4_super_block *es = EXT4_SB(sb)->s_es;
+
+ if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
+ return;
+
+ ext4_warning(sb, __FUNCTION__,
+ "updating to rev %d because of new feature flag, "
+ "running e2fsck is recommended",
+ EXT4_DYNAMIC_REV);
+
+ es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
+ es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
+ es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
+ /* leave es->s_feature_*compat flags alone */
+ /* es->s_uuid will be set by e2fsck if empty */
+
+ /*
+ * The rest of the superblock fields should be zero, and if not it
+ * means they are likely already in use, so leave them alone. We
+ * can leave it up to e2fsck to clean up any inconsistencies there.
+ */
+}
+
+/*
+ * Open the external journal device
+ */
+static struct block_device *ext4_blkdev_get(dev_t dev)
+{
+ struct block_device *bdev;
+ char b[BDEVNAME_SIZE];
+
+ bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
+ if (IS_ERR(bdev))
+ goto fail;
+ return bdev;
+
+fail:
+ printk(KERN_ERR "EXT4: failed to open journal device %s: %ld\n",
+ __bdevname(dev, b), PTR_ERR(bdev));
+ return NULL;
+}
+
+/*
+ * Release the journal device
+ */
+static int ext4_blkdev_put(struct block_device *bdev)
+{
+ bd_release(bdev);
+ return blkdev_put(bdev);
+}
+
+static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
+{
+ struct block_device *bdev;
+ int ret = -ENODEV;
+
+ bdev = sbi->journal_bdev;
+ if (bdev) {
+ ret = ext4_blkdev_put(bdev);
+ sbi->journal_bdev = NULL;
+ }
+ return ret;
+}
+
+static inline struct inode *orphan_list_entry(struct list_head *l)
+{
+ return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
+}
+
+static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
+{
+ struct list_head *l;
+
+ printk(KERN_ERR "sb orphan head is %d\n",
+ le32_to_cpu(sbi->s_es->s_last_orphan));
+
+ printk(KERN_ERR "sb_info orphan list:\n");
+ list_for_each(l, &sbi->s_orphan) {
+ struct inode *inode = orphan_list_entry(l);
+ printk(KERN_ERR " "
+ "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
+ inode->i_sb->s_id, inode->i_ino, inode,
+ inode->i_mode, inode->i_nlink,
+ NEXT_ORPHAN(inode));
+ }
+}
+
+static void ext4_put_super (struct super_block * sb)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+ int i;
+
+ ext4_ext_release(sb);
+ ext4_xattr_put_super(sb);
+ jbd2_journal_destroy(sbi->s_journal);
+ if (!(sb->s_flags & MS_RDONLY)) {
+ EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+ es->s_state = cpu_to_le16(sbi->s_mount_state);
+ BUFFER_TRACE(sbi->s_sbh, "marking dirty");
+ mark_buffer_dirty(sbi->s_sbh);
+ ext4_commit_super(sb, es, 1);
+ }
+
+ for (i = 0; i < sbi->s_gdb_count; i++)
+ brelse(sbi->s_group_desc[i]);
+ kfree(sbi->s_group_desc);
+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
+ percpu_counter_destroy(&sbi->s_dirs_counter);
+ brelse(sbi->s_sbh);
+#ifdef CONFIG_QUOTA
+ for (i = 0; i < MAXQUOTAS; i++)
+ kfree(sbi->s_qf_names[i]);
+#endif
+
+ /* Debugging code just in case the in-memory inode orphan list
+ * isn't empty. The on-disk one can be non-empty if we've
+ * detected an error and taken the fs readonly, but the
+ * in-memory list had better be clean by this point. */
+ if (!list_empty(&sbi->s_orphan))
+ dump_orphan_list(sb, sbi);
+ J_ASSERT(list_empty(&sbi->s_orphan));
+
+ invalidate_bdev(sb->s_bdev, 0);
+ if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
+ /*
+ * Invalidate the journal device's buffers. We don't want them
+ * floating about in memory - the physical journal device may
+ * hotswapped, and it breaks the `ro-after' testing code.
+ */
+ sync_blockdev(sbi->journal_bdev);
+ invalidate_bdev(sbi->journal_bdev, 0);
+ ext4_blkdev_remove(sbi);
+ }
+ sb->s_fs_info = NULL;
+ kfree(sbi);
+ return;
+}
+
+static kmem_cache_t *ext4_inode_cachep;
+
+/*
+ * Called inside transaction, so use GFP_NOFS
+ */
+static struct inode *ext4_alloc_inode(struct super_block *sb)
+{
+ struct ext4_inode_info *ei;
+
+ ei = kmem_cache_alloc(ext4_inode_cachep, SLAB_NOFS);
+ if (!ei)
+ return NULL;
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ ei->i_acl = EXT4_ACL_NOT_CACHED;
+ ei->i_default_acl = EXT4_ACL_NOT_CACHED;
+#endif
+ ei->i_block_alloc_info = NULL;
+ ei->vfs_inode.i_version = 1;
+ memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
+ return &ei->vfs_inode;
+}
+
+static void ext4_destroy_inode(struct inode *inode)
+{
+ kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
+}
+
+static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
+{
+ struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
+
+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR) {
+ INIT_LIST_HEAD(&ei->i_orphan);
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ init_rwsem(&ei->xattr_sem);
+#endif
+ mutex_init(&ei->truncate_mutex);
+ inode_init_once(&ei->vfs_inode);
+ }
+}
+
+static int init_inodecache(void)
+{
+ ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
+ sizeof(struct ext4_inode_info),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ init_once, NULL);
+ if (ext4_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void destroy_inodecache(void)
+{
+ kmem_cache_destroy(ext4_inode_cachep);
+}
+
+static void ext4_clear_inode(struct inode *inode)
+{
+ struct ext4_block_alloc_info *rsv = EXT4_I(inode)->i_block_alloc_info;
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ if (EXT4_I(inode)->i_acl &&
+ EXT4_I(inode)->i_acl != EXT4_ACL_NOT_CACHED) {
+ posix_acl_release(EXT4_I(inode)->i_acl);
+ EXT4_I(inode)->i_acl = EXT4_ACL_NOT_CACHED;
+ }
+ if (EXT4_I(inode)->i_default_acl &&
+ EXT4_I(inode)->i_default_acl != EXT4_ACL_NOT_CACHED) {
+ posix_acl_release(EXT4_I(inode)->i_default_acl);
+ EXT4_I(inode)->i_default_acl = EXT4_ACL_NOT_CACHED;
+ }
+#endif
+ ext4_discard_reservation(inode);
+ EXT4_I(inode)->i_block_alloc_info = NULL;
+ if (unlikely(rsv))
+ kfree(rsv);
+}
+
+static inline void ext4_show_quota_options(struct seq_file *seq, struct super_block *sb)
+{
+#if defined(CONFIG_QUOTA)
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ if (sbi->s_jquota_fmt)
+ seq_printf(seq, ",jqfmt=%s",
+ (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");
+
+ if (sbi->s_qf_names[USRQUOTA])
+ seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
+
+ if (sbi->s_qf_names[GRPQUOTA])
+ seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
+
+ if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
+ seq_puts(seq, ",usrquota");
+
+ if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
+ seq_puts(seq, ",grpquota");
+#endif
+}
+
+static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
+{
+ struct super_block *sb = vfs->mnt_sb;
+
+ if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
+ seq_puts(seq, ",data=journal");
+ else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
+ seq_puts(seq, ",data=ordered");
+ else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
+ seq_puts(seq, ",data=writeback");
+
+ ext4_show_quota_options(seq, sb);
+
+ return 0;
+}
+
+
+static struct dentry *ext4_get_dentry(struct super_block *sb, void *vobjp)
+{
+ __u32 *objp = vobjp;
+ unsigned long ino = objp[0];
+ __u32 generation = objp[1];
+ struct inode *inode;
+ struct dentry *result;
+
+ if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
+ return ERR_PTR(-ESTALE);
+ if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
+ return ERR_PTR(-ESTALE);
+
+ /* iget isn't really right if the inode is currently unallocated!!
+ *
+ * ext4_read_inode will return a bad_inode if the inode had been
+ * deleted, so we should be safe.
+ *
+ * Currently we don't know the generation for parent directory, so
+ * a generation of 0 means "accept any"
+ */
+ inode = iget(sb, ino);
+ if (inode == NULL)
+ return ERR_PTR(-ENOMEM);
+ if (is_bad_inode(inode) ||
+ (generation && inode->i_generation != generation)) {
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ /* now to find a dentry.
+ * If possible, get a well-connected one
+ */
+ result = d_alloc_anon(inode);
+ if (!result) {
+ iput(inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ return result;
+}
+
+#ifdef CONFIG_QUOTA
+#define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
+#define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
+
+static int ext4_dquot_initialize(struct inode *inode, int type);
+static int ext4_dquot_drop(struct inode *inode);
+static int ext4_write_dquot(struct dquot *dquot);
+static int ext4_acquire_dquot(struct dquot *dquot);
+static int ext4_release_dquot(struct dquot *dquot);
+static int ext4_mark_dquot_dirty(struct dquot *dquot);
+static int ext4_write_info(struct super_block *sb, int type);
+static int ext4_quota_on(struct super_block *sb, int type, int format_id, char *path);
+static int ext4_quota_on_mount(struct super_block *sb, int type);
+static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
+ size_t len, loff_t off);
+static ssize_t ext4_quota_write(struct super_block *sb, int type,
+ const char *data, size_t len, loff_t off);
+
+static struct dquot_operations ext4_quota_operations = {
+ .initialize = ext4_dquot_initialize,
+ .drop = ext4_dquot_drop,
+ .alloc_space = dquot_alloc_space,
+ .alloc_inode = dquot_alloc_inode,
+ .free_space = dquot_free_space,
+ .free_inode = dquot_free_inode,
+ .transfer = dquot_transfer,
+ .write_dquot = ext4_write_dquot,
+ .acquire_dquot = ext4_acquire_dquot,
+ .release_dquot = ext4_release_dquot,
+ .mark_dirty = ext4_mark_dquot_dirty,
+ .write_info = ext4_write_info
+};
+
+static struct quotactl_ops ext4_qctl_operations = {
+ .quota_on = ext4_quota_on,
+ .quota_off = vfs_quota_off,
+ .quota_sync = vfs_quota_sync,
+ .get_info = vfs_get_dqinfo,
+ .set_info = vfs_set_dqinfo,
+ .get_dqblk = vfs_get_dqblk,
+ .set_dqblk = vfs_set_dqblk
+};
+#endif
+
+static struct super_operations ext4_sops = {
+ .alloc_inode = ext4_alloc_inode,
+ .destroy_inode = ext4_destroy_inode,
+ .read_inode = ext4_read_inode,
+ .write_inode = ext4_write_inode,
+ .dirty_inode = ext4_dirty_inode,
+ .delete_inode = ext4_delete_inode,
+ .put_super = ext4_put_super,
+ .write_super = ext4_write_super,
+ .sync_fs = ext4_sync_fs,
+ .write_super_lockfs = ext4_write_super_lockfs,
+ .unlockfs = ext4_unlockfs,
+ .statfs = ext4_statfs,
+ .remount_fs = ext4_remount,
+ .clear_inode = ext4_clear_inode,
+ .show_options = ext4_show_options,
+#ifdef CONFIG_QUOTA
+ .quota_read = ext4_quota_read,
+ .quota_write = ext4_quota_write,
+#endif
+};
+
+static struct export_operations ext4_export_ops = {
+ .get_parent = ext4_get_parent,
+ .get_dentry = ext4_get_dentry,
+};
+
+enum {
+ Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
+ Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
+ Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
+ Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
+ Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
+ Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
+ Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
+ Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
+ Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
+ Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
+ Opt_grpquota, Opt_extents,
+};
+
+static match_table_t tokens = {
+ {Opt_bsd_df, "bsddf"},
+ {Opt_minix_df, "minixdf"},
+ {Opt_grpid, "grpid"},
+ {Opt_grpid, "bsdgroups"},
+ {Opt_nogrpid, "nogrpid"},
+ {Opt_nogrpid, "sysvgroups"},
+ {Opt_resgid, "resgid=%u"},
+ {Opt_resuid, "resuid=%u"},
+ {Opt_sb, "sb=%u"},
+ {Opt_err_cont, "errors=continue"},
+ {Opt_err_panic, "errors=panic"},
+ {Opt_err_ro, "errors=remount-ro"},
+ {Opt_nouid32, "nouid32"},
+ {Opt_nocheck, "nocheck"},
+ {Opt_nocheck, "check=none"},
+ {Opt_debug, "debug"},
+ {Opt_oldalloc, "oldalloc"},
+ {Opt_orlov, "orlov"},
+ {Opt_user_xattr, "user_xattr"},
+ {Opt_nouser_xattr, "nouser_xattr"},
+ {Opt_acl, "acl"},
+ {Opt_noacl, "noacl"},
+ {Opt_reservation, "reservation"},
+ {Opt_noreservation, "noreservation"},
+ {Opt_noload, "noload"},
+ {Opt_nobh, "nobh"},
+ {Opt_bh, "bh"},
+ {Opt_commit, "commit=%u"},
+ {Opt_journal_update, "journal=update"},
+ {Opt_journal_inum, "journal=%u"},
+ {Opt_journal_dev, "journal_dev=%u"},
+ {Opt_abort, "abort"},
+ {Opt_data_journal, "data=journal"},
+ {Opt_data_ordered, "data=ordered"},
+ {Opt_data_writeback, "data=writeback"},
+ {Opt_offusrjquota, "usrjquota="},
+ {Opt_usrjquota, "usrjquota=%s"},
+ {Opt_offgrpjquota, "grpjquota="},
+ {Opt_grpjquota, "grpjquota=%s"},
+ {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
+ {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
+ {Opt_grpquota, "grpquota"},
+ {Opt_noquota, "noquota"},
+ {Opt_quota, "quota"},
+ {Opt_usrquota, "usrquota"},
+ {Opt_barrier, "barrier=%u"},
+ {Opt_extents, "extents"},
+ {Opt_err, NULL},
+ {Opt_resize, "resize"},
+};
+
+static ext4_fsblk_t get_sb_block(void **data)
+{
+ ext4_fsblk_t sb_block;
+ char *options = (char *) *data;
+
+ if (!options || strncmp(options, "sb=", 3) != 0)
+ return 1; /* Default location */
+ options += 3;
+ /*todo: use simple_strtoll with >32bit ext4 */
+ sb_block = simple_strtoul(options, &options, 0);
+ if (*options && *options != ',') {
+ printk("EXT4-fs: Invalid sb specification: %s\n",
+ (char *) *data);
+ return 1;
+ }
+ if (*options == ',')
+ options++;
+ *data = (void *) options;
+ return sb_block;
+}
+
+static int parse_options (char *options, struct super_block *sb,
+ unsigned int *inum, unsigned long *journal_devnum,
+ ext4_fsblk_t *n_blocks_count, int is_remount)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ char * p;
+ substring_t args[MAX_OPT_ARGS];
+ int data_opt = 0;
+ int option;
+#ifdef CONFIG_QUOTA
+ int qtype;
+ char *qname;
+#endif
+
+ if (!options)
+ return 1;
+
+ while ((p = strsep (&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_bsd_df:
+ clear_opt (sbi->s_mount_opt, MINIX_DF);
+ break;
+ case Opt_minix_df:
+ set_opt (sbi->s_mount_opt, MINIX_DF);
+ break;
+ case Opt_grpid:
+ set_opt (sbi->s_mount_opt, GRPID);
+ break;
+ case Opt_nogrpid:
+ clear_opt (sbi->s_mount_opt, GRPID);
+ break;
+ case Opt_resuid:
+ if (match_int(&args[0], &option))
+ return 0;
+ sbi->s_resuid = option;
+ break;
+ case Opt_resgid:
+ if (match_int(&args[0], &option))
+ return 0;
+ sbi->s_resgid = option;
+ break;
+ case Opt_sb:
+ /* handled by get_sb_block() instead of here */
+ /* *sb_block = match_int(&args[0]); */
+ break;
+ case Opt_err_panic:
+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
+ set_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ break;
+ case Opt_err_ro:
+ clear_opt (sbi->s_mount_opt, ERRORS_CONT);
+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ set_opt (sbi->s_mount_opt, ERRORS_RO);
+ break;
+ case Opt_err_cont:
+ clear_opt (sbi->s_mount_opt, ERRORS_RO);
+ clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
+ set_opt (sbi->s_mount_opt, ERRORS_CONT);
+ break;
+ case Opt_nouid32:
+ set_opt (sbi->s_mount_opt, NO_UID32);
+ break;
+ case Opt_nocheck:
+ clear_opt (sbi->s_mount_opt, CHECK);
+ break;
+ case Opt_debug:
+ set_opt (sbi->s_mount_opt, DEBUG);
+ break;
+ case Opt_oldalloc:
+ set_opt (sbi->s_mount_opt, OLDALLOC);
+ break;
+ case Opt_orlov:
+ clear_opt (sbi->s_mount_opt, OLDALLOC);
+ break;
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ case Opt_user_xattr:
+ set_opt (sbi->s_mount_opt, XATTR_USER);
+ break;
+ case Opt_nouser_xattr:
+ clear_opt (sbi->s_mount_opt, XATTR_USER);
+ break;
+#else
+ case Opt_user_xattr:
+ case Opt_nouser_xattr:
+ printk("EXT4 (no)user_xattr options not supported\n");
+ break;
+#endif
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ case Opt_acl:
+ set_opt(sbi->s_mount_opt, POSIX_ACL);
+ break;
+ case Opt_noacl:
+ clear_opt(sbi->s_mount_opt, POSIX_ACL);
+ break;
+#else
+ case Opt_acl:
+ case Opt_noacl:
+ printk("EXT4 (no)acl options not supported\n");
+ break;
+#endif
+ case Opt_reservation:
+ set_opt(sbi->s_mount_opt, RESERVATION);
+ break;
+ case Opt_noreservation:
+ clear_opt(sbi->s_mount_opt, RESERVATION);
+ break;
+ case Opt_journal_update:
+ /* @@@ FIXME */
+ /* Eventually we will want to be able to create
+ a journal file here. For now, only allow the
+ user to specify an existing inode to be the
+ journal file. */
+ if (is_remount) {
+ printk(KERN_ERR "EXT4-fs: cannot specify "
+ "journal on remount\n");
+ return 0;
+ }
+ set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
+ break;
+ case Opt_journal_inum:
+ if (is_remount) {
+ printk(KERN_ERR "EXT4-fs: cannot specify "
+ "journal on remount\n");
+ return 0;
+ }
+ if (match_int(&args[0], &option))
+ return 0;
+ *inum = option;
+ break;
+ case Opt_journal_dev:
+ if (is_remount) {
+ printk(KERN_ERR "EXT4-fs: cannot specify "
+ "journal on remount\n");
+ return 0;
+ }
+ if (match_int(&args[0], &option))
+ return 0;
+ *journal_devnum = option;
+ break;
+ case Opt_noload:
+ set_opt (sbi->s_mount_opt, NOLOAD);
+ break;
+ case Opt_commit:
+ if (match_int(&args[0], &option))
+ return 0;
+ if (option < 0)
+ return 0;
+ if (option == 0)
+ option = JBD_DEFAULT_MAX_COMMIT_AGE;
+ sbi->s_commit_interval = HZ * option;
+ break;
+ case Opt_data_journal:
+ data_opt = EXT4_MOUNT_JOURNAL_DATA;
+ goto datacheck;
+ case Opt_data_ordered:
+ data_opt = EXT4_MOUNT_ORDERED_DATA;
+ goto datacheck;
+ case Opt_data_writeback:
+ data_opt = EXT4_MOUNT_WRITEBACK_DATA;
+ datacheck:
+ if (is_remount) {
+ if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
+ != data_opt) {
+ printk(KERN_ERR
+ "EXT4-fs: cannot change data "
+ "mode on remount\n");
+ return 0;
+ }
+ } else {
+ sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
+ sbi->s_mount_opt |= data_opt;
+ }
+ break;
+#ifdef CONFIG_QUOTA
+ case Opt_usrjquota:
+ qtype = USRQUOTA;
+ goto set_qf_name;
+ case Opt_grpjquota:
+ qtype = GRPQUOTA;
+set_qf_name:
+ if (sb_any_quota_enabled(sb)) {
+ printk(KERN_ERR
+ "EXT4-fs: Cannot change journalled "
+ "quota options when quota turned on.\n");
+ return 0;
+ }
+ qname = match_strdup(&args[0]);
+ if (!qname) {
+ printk(KERN_ERR
+ "EXT4-fs: not enough memory for "
+ "storing quotafile name.\n");
+ return 0;
+ }
+ if (sbi->s_qf_names[qtype] &&
+ strcmp(sbi->s_qf_names[qtype], qname)) {
+ printk(KERN_ERR
+ "EXT4-fs: %s quota file already "
+ "specified.\n", QTYPE2NAME(qtype));
+ kfree(qname);
+ return 0;
+ }
+ sbi->s_qf_names[qtype] = qname;
+ if (strchr(sbi->s_qf_names[qtype], '/')) {
+ printk(KERN_ERR
+ "EXT4-fs: quotafile must be on "
+ "filesystem root.\n");
+ kfree(sbi->s_qf_names[qtype]);
+ sbi->s_qf_names[qtype] = NULL;
+ return 0;
+ }
+ set_opt(sbi->s_mount_opt, QUOTA);
+ break;
+ case Opt_offusrjquota:
+ qtype = USRQUOTA;
+ goto clear_qf_name;
+ case Opt_offgrpjquota:
+ qtype = GRPQUOTA;
+clear_qf_name:
+ if (sb_any_quota_enabled(sb)) {
+ printk(KERN_ERR "EXT4-fs: Cannot change "
+ "journalled quota options when "
+ "quota turned on.\n");
+ return 0;
+ }
+ /*
+ * The space will be released later when all options
+ * are confirmed to be correct
+ */
+ sbi->s_qf_names[qtype] = NULL;
+ break;
+ case Opt_jqfmt_vfsold:
+ sbi->s_jquota_fmt = QFMT_VFS_OLD;
+ break;
+ case Opt_jqfmt_vfsv0:
+ sbi->s_jquota_fmt = QFMT_VFS_V0;
+ break;
+ case Opt_quota:
+ case Opt_usrquota:
+ set_opt(sbi->s_mount_opt, QUOTA);
+ set_opt(sbi->s_mount_opt, USRQUOTA);
+ break;
+ case Opt_grpquota:
+ set_opt(sbi->s_mount_opt, QUOTA);
+ set_opt(sbi->s_mount_opt, GRPQUOTA);
+ break;
+ case Opt_noquota:
+ if (sb_any_quota_enabled(sb)) {
+ printk(KERN_ERR "EXT4-fs: Cannot change quota "
+ "options when quota turned on.\n");
+ return 0;
+ }
+ clear_opt(sbi->s_mount_opt, QUOTA);
+ clear_opt(sbi->s_mount_opt, USRQUOTA);
+ clear_opt(sbi->s_mount_opt, GRPQUOTA);
+ break;
+#else
+ case Opt_quota:
+ case Opt_usrquota:
+ case Opt_grpquota:
+ case Opt_usrjquota:
+ case Opt_grpjquota:
+ case Opt_offusrjquota:
+ case Opt_offgrpjquota:
+ case Opt_jqfmt_vfsold:
+ case Opt_jqfmt_vfsv0:
+ printk(KERN_ERR
+ "EXT4-fs: journalled quota options not "
+ "supported.\n");
+ break;
+ case Opt_noquota:
+ break;
+#endif
+ case Opt_abort:
+ set_opt(sbi->s_mount_opt, ABORT);
+ break;
+ case Opt_barrier:
+ if (match_int(&args[0], &option))
+ return 0;
+ if (option)
+ set_opt(sbi->s_mount_opt, BARRIER);
+ else
+ clear_opt(sbi->s_mount_opt, BARRIER);
+ break;
+ case Opt_ignore:
+ break;
+ case Opt_resize:
+ if (!is_remount) {
+ printk("EXT4-fs: resize option only available "
+ "for remount\n");
+ return 0;
+ }
+ if (match_int(&args[0], &option) != 0)
+ return 0;
+ *n_blocks_count = option;
+ break;
+ case Opt_nobh:
+ set_opt(sbi->s_mount_opt, NOBH);
+ break;
+ case Opt_bh:
+ clear_opt(sbi->s_mount_opt, NOBH);
+ break;
+ case Opt_extents:
+ set_opt (sbi->s_mount_opt, EXTENTS);
+ break;
+ default:
+ printk (KERN_ERR
+ "EXT4-fs: Unrecognized mount option \"%s\" "
+ "or missing value\n", p);
+ return 0;
+ }
+ }
+#ifdef CONFIG_QUOTA
+ if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
+ if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
+ sbi->s_qf_names[USRQUOTA])
+ clear_opt(sbi->s_mount_opt, USRQUOTA);
+
+ if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
+ sbi->s_qf_names[GRPQUOTA])
+ clear_opt(sbi->s_mount_opt, GRPQUOTA);
+
+ if ((sbi->s_qf_names[USRQUOTA] &&
+ (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
+ (sbi->s_qf_names[GRPQUOTA] &&
+ (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
+ printk(KERN_ERR "EXT4-fs: old and new quota "
+ "format mixing.\n");
+ return 0;
+ }
+
+ if (!sbi->s_jquota_fmt) {
+ printk(KERN_ERR "EXT4-fs: journalled quota format "
+ "not specified.\n");
+ return 0;
+ }
+ } else {
+ if (sbi->s_jquota_fmt) {
+ printk(KERN_ERR "EXT4-fs: journalled quota format "
+ "specified with no journalling "
+ "enabled.\n");
+ return 0;
+ }
+ }
+#endif
+ return 1;
+}
+
+static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
+ int read_only)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ int res = 0;
+
+ if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
+ printk (KERN_ERR "EXT4-fs warning: revision level too high, "
+ "forcing read-only mode\n");
+ res = MS_RDONLY;
+ }
+ if (read_only)
+ return res;
+ if (!(sbi->s_mount_state & EXT4_VALID_FS))
+ printk (KERN_WARNING "EXT4-fs warning: mounting unchecked fs, "
+ "running e2fsck is recommended\n");
+ else if ((sbi->s_mount_state & EXT4_ERROR_FS))
+ printk (KERN_WARNING
+ "EXT4-fs warning: mounting fs with errors, "
+ "running e2fsck is recommended\n");
+ else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
+ le16_to_cpu(es->s_mnt_count) >=
+ (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
+ printk (KERN_WARNING
+ "EXT4-fs warning: maximal mount count reached, "
+ "running e2fsck is recommended\n");
+ else if (le32_to_cpu(es->s_checkinterval) &&
+ (le32_to_cpu(es->s_lastcheck) +
+ le32_to_cpu(es->s_checkinterval) <= get_seconds()))
+ printk (KERN_WARNING
+ "EXT4-fs warning: checktime reached, "
+ "running e2fsck is recommended\n");
+#if 0
+ /* @@@ We _will_ want to clear the valid bit if we find
+ * inconsistencies, to force a fsck at reboot. But for
+ * a plain journaled filesystem we can keep it set as
+ * valid forever! :)
+ */
+ es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT4_VALID_FS);
+#endif
+ if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
+ es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
+ es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
+ es->s_mtime = cpu_to_le32(get_seconds());
+ ext4_update_dynamic_rev(sb);
+ EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+
+ ext4_commit_super(sb, es, 1);
+ if (test_opt(sb, DEBUG))
+ printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%lu, "
+ "bpg=%lu, ipg=%lu, mo=%04lx]\n",
+ sb->s_blocksize,
+ sbi->s_groups_count,
+ EXT4_BLOCKS_PER_GROUP(sb),
+ EXT4_INODES_PER_GROUP(sb),
+ sbi->s_mount_opt);
+
+ printk(KERN_INFO "EXT4 FS on %s, ", sb->s_id);
+ if (EXT4_SB(sb)->s_journal->j_inode == NULL) {
+ char b[BDEVNAME_SIZE];
+
+ printk("external journal on %s\n",
+ bdevname(EXT4_SB(sb)->s_journal->j_dev, b));
+ } else {
+ printk("internal journal\n");
+ }
+ return res;
+}
+
+/* Called at mount-time, super-block is locked */
+static int ext4_check_descriptors (struct super_block * sb)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
+ ext4_fsblk_t last_block;
+ ext4_fsblk_t block_bitmap;
+ ext4_fsblk_t inode_bitmap;
+ ext4_fsblk_t inode_table;
+ struct ext4_group_desc * gdp = NULL;
+ int desc_block = 0;
+ int i;
+
+ ext4_debug ("Checking group descriptors");
+
+ for (i = 0; i < sbi->s_groups_count; i++)
+ {
+ if (i == sbi->s_groups_count - 1)
+ last_block = ext4_blocks_count(sbi->s_es) - 1;
+ else
+ last_block = first_block +
+ (EXT4_BLOCKS_PER_GROUP(sb) - 1);
+
+ if ((i % EXT4_DESC_PER_BLOCK(sb)) == 0)
+ gdp = (struct ext4_group_desc *)
+ sbi->s_group_desc[desc_block++]->b_data;
+ block_bitmap = ext4_block_bitmap(sb, gdp);
+ if (block_bitmap < first_block || block_bitmap > last_block)
+ {
+ ext4_error (sb, "ext4_check_descriptors",
+ "Block bitmap for group %d"
+ " not in group (block %llu)!",
+ i, block_bitmap);
+ return 0;
+ }
+ inode_bitmap = ext4_inode_bitmap(sb, gdp);
+ if (inode_bitmap < first_block || inode_bitmap > last_block)
+ {
+ ext4_error (sb, "ext4_check_descriptors",
+ "Inode bitmap for group %d"
+ " not in group (block %llu)!",
+ i, inode_bitmap);
+ return 0;
+ }
+ inode_table = ext4_inode_table(sb, gdp);
+ if (inode_table < first_block ||
+ inode_table + sbi->s_itb_per_group > last_block)
+ {
+ ext4_error (sb, "ext4_check_descriptors",
+ "Inode table for group %d"
+ " not in group (block %llu)!",
+ i, inode_table);
+ return 0;
+ }
+ first_block += EXT4_BLOCKS_PER_GROUP(sb);
+ gdp = (struct ext4_group_desc *)
+ ((__u8 *)gdp + EXT4_DESC_SIZE(sb));
+ }
+
+ ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
+ sbi->s_es->s_free_inodes_count=cpu_to_le32(ext4_count_free_inodes(sb));
+ return 1;
+}
+
+
+/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
+ * the superblock) which were deleted from all directories, but held open by
+ * a process at the time of a crash. We walk the list and try to delete these
+ * inodes at recovery time (only with a read-write filesystem).
+ *
+ * In order to keep the orphan inode chain consistent during traversal (in
+ * case of crash during recovery), we link each inode into the superblock
+ * orphan list_head and handle it the same way as an inode deletion during
+ * normal operation (which journals the operations for us).
+ *
+ * We only do an iget() and an iput() on each inode, which is very safe if we
+ * accidentally point at an in-use or already deleted inode. The worst that
+ * can happen in this case is that we get a "bit already cleared" message from
+ * ext4_free_inode(). The only reason we would point at a wrong inode is if
+ * e2fsck was run on this filesystem, and it must have already done the orphan
+ * inode cleanup for us, so we can safely abort without any further action.
+ */
+static void ext4_orphan_cleanup (struct super_block * sb,
+ struct ext4_super_block * es)
+{
+ unsigned int s_flags = sb->s_flags;
+ int nr_orphans = 0, nr_truncates = 0;
+#ifdef CONFIG_QUOTA
+ int i;
+#endif
+ if (!es->s_last_orphan) {
+ jbd_debug(4, "no orphan inodes to clean up\n");
+ return;
+ }
+
+ if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
+ if (es->s_last_orphan)
+ jbd_debug(1, "Errors on filesystem, "
+ "clearing orphan list.\n");
+ es->s_last_orphan = 0;
+ jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
+ return;
+ }
+
+ if (s_flags & MS_RDONLY) {
+ printk(KERN_INFO "EXT4-fs: %s: orphan cleanup on readonly fs\n",
+ sb->s_id);
+ sb->s_flags &= ~MS_RDONLY;
+ }
+#ifdef CONFIG_QUOTA
+ /* Needed for iput() to work correctly and not trash data */
+ sb->s_flags |= MS_ACTIVE;
+ /* Turn on quotas so that they are updated correctly */
+ for (i = 0; i < MAXQUOTAS; i++) {
+ if (EXT4_SB(sb)->s_qf_names[i]) {
+ int ret = ext4_quota_on_mount(sb, i);
+ if (ret < 0)
+ printk(KERN_ERR
+ "EXT4-fs: Cannot turn on journalled "
+ "quota: error %d\n", ret);
+ }
+ }
+#endif
+
+ while (es->s_last_orphan) {
+ struct inode *inode;
+
+ if (!(inode =
+ ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan)))) {
+ es->s_last_orphan = 0;
+ break;
+ }
+
+ list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
+ DQUOT_INIT(inode);
+ if (inode->i_nlink) {
+ printk(KERN_DEBUG
+ "%s: truncating inode %lu to %Ld bytes\n",
+ __FUNCTION__, inode->i_ino, inode->i_size);
+ jbd_debug(2, "truncating inode %lu to %Ld bytes\n",
+ inode->i_ino, inode->i_size);
+ ext4_truncate(inode);
+ nr_truncates++;
+ } else {
+ printk(KERN_DEBUG
+ "%s: deleting unreferenced inode %lu\n",
+ __FUNCTION__, inode->i_ino);
+ jbd_debug(2, "deleting unreferenced inode %lu\n",
+ inode->i_ino);
+ nr_orphans++;
+ }
+ iput(inode); /* The delete magic happens here! */
+ }
+
+#define PLURAL(x) (x), ((x)==1) ? "" : "s"
+
+ if (nr_orphans)
+ printk(KERN_INFO "EXT4-fs: %s: %d orphan inode%s deleted\n",
+ sb->s_id, PLURAL(nr_orphans));
+ if (nr_truncates)
+ printk(KERN_INFO "EXT4-fs: %s: %d truncate%s cleaned up\n",
+ sb->s_id, PLURAL(nr_truncates));
+#ifdef CONFIG_QUOTA
+ /* Turn quotas off */
+ for (i = 0; i < MAXQUOTAS; i++) {
+ if (sb_dqopt(sb)->files[i])
+ vfs_quota_off(sb, i);
+ }
+#endif
+ sb->s_flags = s_flags; /* Restore MS_RDONLY status */
+}
+
+#define log2(n) ffz(~(n))
+
+/*
+ * Maximal file size. There is a direct, and {,double-,triple-}indirect
+ * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
+ * We need to be 1 filesystem block less than the 2^32 sector limit.
+ */
+static loff_t ext4_max_size(int bits)
+{
+ loff_t res = EXT4_NDIR_BLOCKS;
+ /* This constant is calculated to be the largest file size for a
+ * dense, 4k-blocksize file such that the total number of
+ * sectors in the file, including data and all indirect blocks,
+ * does not exceed 2^32. */
+ const loff_t upper_limit = 0x1ff7fffd000LL;
+
+ res += 1LL << (bits-2);
+ res += 1LL << (2*(bits-2));
+ res += 1LL << (3*(bits-2));
+ res <<= bits;
+ if (res > upper_limit)
+ res = upper_limit;
+ return res;
+}
+
+static ext4_fsblk_t descriptor_loc(struct super_block *sb,
+ ext4_fsblk_t logical_sb_block, int nr)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ unsigned long bg, first_meta_bg;
+ int has_super = 0;
+
+ first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
+
+ if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
+ nr < first_meta_bg)
+ return logical_sb_block + nr + 1;
+ bg = sbi->s_desc_per_block * nr;
+ if (ext4_bg_has_super(sb, bg))
+ has_super = 1;
+ return (has_super + ext4_group_first_block_no(sb, bg));
+}
+
+
+static int ext4_fill_super (struct super_block *sb, void *data, int silent)
+{
+ struct buffer_head * bh;
+ struct ext4_super_block *es = NULL;
+ struct ext4_sb_info *sbi;
+ ext4_fsblk_t block;
+ ext4_fsblk_t sb_block = get_sb_block(&data);
+ ext4_fsblk_t logical_sb_block;
+ unsigned long offset = 0;
+ unsigned int journal_inum = 0;
+ unsigned long journal_devnum = 0;
+ unsigned long def_mount_opts;
+ struct inode *root;
+ int blocksize;
+ int hblock;
+ int db_count;
+ int i;
+ int needs_recovery;
+ __le32 features;
+ __u64 blocks_count;
+
+ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+ sb->s_fs_info = sbi;
+ sbi->s_mount_opt = 0;
+ sbi->s_resuid = EXT4_DEF_RESUID;
+ sbi->s_resgid = EXT4_DEF_RESGID;
+
+ unlock_kernel();
+
+ blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
+ if (!blocksize) {
+ printk(KERN_ERR "EXT4-fs: unable to set blocksize\n");
+ goto out_fail;
+ }
+
+ /*
+ * The ext4 superblock will not be buffer aligned for other than 1kB
+ * block sizes. We need to calculate the offset from buffer start.
+ */
+ if (blocksize != EXT4_MIN_BLOCK_SIZE) {
+ logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
+ offset = do_div(logical_sb_block, blocksize);
+ } else {
+ logical_sb_block = sb_block;
+ }
+
+ if (!(bh = sb_bread(sb, logical_sb_block))) {
+ printk (KERN_ERR "EXT4-fs: unable to read superblock\n");
+ goto out_fail;
+ }
+ /*
+ * Note: s_es must be initialized as soon as possible because
+ * some ext4 macro-instructions depend on its value
+ */
+ es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
+ sbi->s_es = es;
+ sb->s_magic = le16_to_cpu(es->s_magic);
+ if (sb->s_magic != EXT4_SUPER_MAGIC)
+ goto cantfind_ext4;
+
+ /* Set defaults before we parse the mount options */
+ def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
+ if (def_mount_opts & EXT4_DEFM_DEBUG)
+ set_opt(sbi->s_mount_opt, DEBUG);
+ if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
+ set_opt(sbi->s_mount_opt, GRPID);
+ if (def_mount_opts & EXT4_DEFM_UID16)
+ set_opt(sbi->s_mount_opt, NO_UID32);
+ if (def_mount_opts & EXT4_DEFM_XATTR_USER)
+ set_opt(sbi->s_mount_opt, XATTR_USER);
+ if (def_mount_opts & EXT4_DEFM_ACL)
+ set_opt(sbi->s_mount_opt, POSIX_ACL);
+ if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
+ sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
+ else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
+ sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
+ else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
+ sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
+
+ if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
+ set_opt(sbi->s_mount_opt, ERRORS_PANIC);
+ else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_RO)
+ set_opt(sbi->s_mount_opt, ERRORS_RO);
+ else
+ set_opt(sbi->s_mount_opt, ERRORS_CONT);
+
+ sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
+ sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
+
+ set_opt(sbi->s_mount_opt, RESERVATION);
+
+ if (!parse_options ((char *) data, sb, &journal_inum, &journal_devnum,
+ NULL, 0))
+ goto failed_mount;
+
+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
+ ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
+
+ if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
+ (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
+ EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
+ EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
+ printk(KERN_WARNING
+ "EXT4-fs warning: feature flags set on rev 0 fs, "
+ "running e2fsck is recommended\n");
+ /*
+ * Check feature flags regardless of the revision level, since we
+ * previously didn't change the revision level when setting the flags,
+ * so there is a chance incompat flags are set on a rev 0 filesystem.
+ */
+ features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
+ if (features) {
+ printk(KERN_ERR "EXT4-fs: %s: couldn't mount because of "
+ "unsupported optional features (%x).\n",
+ sb->s_id, le32_to_cpu(features));
+ goto failed_mount;
+ }
+ features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
+ if (!(sb->s_flags & MS_RDONLY) && features) {
+ printk(KERN_ERR "EXT4-fs: %s: couldn't mount RDWR because of "
+ "unsupported optional features (%x).\n",
+ sb->s_id, le32_to_cpu(features));
+ goto failed_mount;
+ }
+ blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
+
+ if (blocksize < EXT4_MIN_BLOCK_SIZE ||
+ blocksize > EXT4_MAX_BLOCK_SIZE) {
+ printk(KERN_ERR
+ "EXT4-fs: Unsupported filesystem blocksize %d on %s.\n",
+ blocksize, sb->s_id);
+ goto failed_mount;
+ }
+
+ hblock = bdev_hardsect_size(sb->s_bdev);
+ if (sb->s_blocksize != blocksize) {
+ /*
+ * Make sure the blocksize for the filesystem is larger
+ * than the hardware sectorsize for the machine.
+ */
+ if (blocksize < hblock) {
+ printk(KERN_ERR "EXT4-fs: blocksize %d too small for "
+ "device blocksize %d.\n", blocksize, hblock);
+ goto failed_mount;
+ }
+
+ brelse (bh);
+ sb_set_blocksize(sb, blocksize);
+ logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
+ offset = do_div(logical_sb_block, blocksize);
+ bh = sb_bread(sb, logical_sb_block);
+ if (!bh) {
+ printk(KERN_ERR
+ "EXT4-fs: Can't read superblock on 2nd try.\n");
+ goto failed_mount;
+ }
+ es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
+ sbi->s_es = es;
+ if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
+ printk (KERN_ERR
+ "EXT4-fs: Magic mismatch, very weird !\n");
+ goto failed_mount;
+ }
+ }
+
+ sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits);
+
+ if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
+ sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
+ sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
+ } else {
+ sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
+ sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
+ if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
+ (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
+ (sbi->s_inode_size > blocksize)) {
+ printk (KERN_ERR
+ "EXT4-fs: unsupported inode size: %d\n",
+ sbi->s_inode_size);
+ goto failed_mount;
+ }
+ }
+ sbi->s_frag_size = EXT4_MIN_FRAG_SIZE <<
+ le32_to_cpu(es->s_log_frag_size);
+ if (blocksize != sbi->s_frag_size) {
+ printk(KERN_ERR
+ "EXT4-fs: fragsize %lu != blocksize %u (unsupported)\n",
+ sbi->s_frag_size, blocksize);
+ goto failed_mount;
+ }
+ sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
+ if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
+ if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
+ sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
+ sbi->s_desc_size & (sbi->s_desc_size - 1)) {
+ printk(KERN_ERR
+ "EXT4-fs: unsupported descriptor size %lu\n",
+ sbi->s_desc_size);
+ goto failed_mount;
+ }
+ } else
+ sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
+ sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
+ sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
+ sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
+ if (EXT4_INODE_SIZE(sb) == 0)
+ goto cantfind_ext4;
+ sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
+ if (sbi->s_inodes_per_block == 0)
+ goto cantfind_ext4;
+ sbi->s_itb_per_group = sbi->s_inodes_per_group /
+ sbi->s_inodes_per_block;
+ sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
+ sbi->s_sbh = bh;
+ sbi->s_mount_state = le16_to_cpu(es->s_state);
+ sbi->s_addr_per_block_bits = log2(EXT4_ADDR_PER_BLOCK(sb));
+ sbi->s_desc_per_block_bits = log2(EXT4_DESC_PER_BLOCK(sb));
+ for (i=0; i < 4; i++)
+ sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
+ sbi->s_def_hash_version = es->s_def_hash_version;
+
+ if (sbi->s_blocks_per_group > blocksize * 8) {
+ printk (KERN_ERR
+ "EXT4-fs: #blocks per group too big: %lu\n",
+ sbi->s_blocks_per_group);
+ goto failed_mount;
+ }
+ if (sbi->s_frags_per_group > blocksize * 8) {
+ printk (KERN_ERR
+ "EXT4-fs: #fragments per group too big: %lu\n",
+ sbi->s_frags_per_group);
+ goto failed_mount;
+ }
+ if (sbi->s_inodes_per_group > blocksize * 8) {
+ printk (KERN_ERR
+ "EXT4-fs: #inodes per group too big: %lu\n",
+ sbi->s_inodes_per_group);
+ goto failed_mount;
+ }
+
+ if (ext4_blocks_count(es) >
+ (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
+ printk(KERN_ERR "EXT4-fs: filesystem on %s:"
+ " too large to mount safely\n", sb->s_id);
+ if (sizeof(sector_t) < 8)
+ printk(KERN_WARNING "EXT4-fs: CONFIG_LBD not "
+ "enabled\n");
+ goto failed_mount;
+ }
+
+ if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
+ goto cantfind_ext4;
+ blocks_count = (ext4_blocks_count(es) -
+ le32_to_cpu(es->s_first_data_block) +
+ EXT4_BLOCKS_PER_GROUP(sb) - 1);
+ do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
+ sbi->s_groups_count = blocks_count;
+ db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
+ EXT4_DESC_PER_BLOCK(sb);
+ sbi->s_group_desc = kmalloc(db_count * sizeof (struct buffer_head *),
+ GFP_KERNEL);
+ if (sbi->s_group_desc == NULL) {
+ printk (KERN_ERR "EXT4-fs: not enough memory\n");
+ goto failed_mount;
+ }
+
+ bgl_lock_init(&sbi->s_blockgroup_lock);
+
+ for (i = 0; i < db_count; i++) {
+ block = descriptor_loc(sb, logical_sb_block, i);
+ sbi->s_group_desc[i] = sb_bread(sb, block);
+ if (!sbi->s_group_desc[i]) {
+ printk (KERN_ERR "EXT4-fs: "
+ "can't read group descriptor %d\n", i);
+ db_count = i;
+ goto failed_mount2;
+ }
+ }
+ if (!ext4_check_descriptors (sb)) {
+ printk(KERN_ERR "EXT4-fs: group descriptors corrupted!\n");
+ goto failed_mount2;
+ }
+ sbi->s_gdb_count = db_count;
+ get_random_bytes(&sbi->s_next_generation, sizeof(u32));
+ spin_lock_init(&sbi->s_next_gen_lock);
+
+ percpu_counter_init(&sbi->s_freeblocks_counter,
+ ext4_count_free_blocks(sb));
+ percpu_counter_init(&sbi->s_freeinodes_counter,
+ ext4_count_free_inodes(sb));
+ percpu_counter_init(&sbi->s_dirs_counter,
+ ext4_count_dirs(sb));
+
+ /* per fileystem reservation list head & lock */
+ spin_lock_init(&sbi->s_rsv_window_lock);
+ sbi->s_rsv_window_root = RB_ROOT;
+ /* Add a single, static dummy reservation to the start of the
+ * reservation window list --- it gives us a placeholder for
+ * append-at-start-of-list which makes the allocation logic
+ * _much_ simpler. */
+ sbi->s_rsv_window_head.rsv_start = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+ sbi->s_rsv_window_head.rsv_end = EXT4_RESERVE_WINDOW_NOT_ALLOCATED;
+ sbi->s_rsv_window_head.rsv_alloc_hit = 0;
+ sbi->s_rsv_window_head.rsv_goal_size = 0;
+ ext4_rsv_window_add(sb, &sbi->s_rsv_window_head);
+
+ /*
+ * set up enough so that it can read an inode
+ */
+ sb->s_op = &ext4_sops;
+ sb->s_export_op = &ext4_export_ops;
+ sb->s_xattr = ext4_xattr_handlers;
+#ifdef CONFIG_QUOTA
+ sb->s_qcop = &ext4_qctl_operations;
+ sb->dq_op = &ext4_quota_operations;
+#endif
+ INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
+
+ sb->s_root = NULL;
+
+ needs_recovery = (es->s_last_orphan != 0 ||
+ EXT4_HAS_INCOMPAT_FEATURE(sb,
+ EXT4_FEATURE_INCOMPAT_RECOVER));
+
+ /*
+ * The first inode we look at is the journal inode. Don't try
+ * root first: it may be modified in the journal!
+ */
+ if (!test_opt(sb, NOLOAD) &&
+ EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
+ if (ext4_load_journal(sb, es, journal_devnum))
+ goto failed_mount3;
+ } else if (journal_inum) {
+ if (ext4_create_journal(sb, es, journal_inum))
+ goto failed_mount3;
+ } else {
+ if (!silent)
+ printk (KERN_ERR
+ "ext4: No journal on filesystem on %s\n",
+ sb->s_id);
+ goto failed_mount3;
+ }
+
+ /* We have now updated the journal if required, so we can
+ * validate the data journaling mode. */
+ switch (test_opt(sb, DATA_FLAGS)) {
+ case 0:
+ /* No mode set, assume a default based on the journal
+ * capabilities: ORDERED_DATA if the journal can
+ * cope, else JOURNAL_DATA
+ */
+ if (jbd2_journal_check_available_features
+ (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
+ set_opt(sbi->s_mount_opt, ORDERED_DATA);
+ else
+ set_opt(sbi->s_mount_opt, JOURNAL_DATA);
+ break;
+
+ case EXT4_MOUNT_ORDERED_DATA:
+ case EXT4_MOUNT_WRITEBACK_DATA:
+ if (!jbd2_journal_check_available_features
+ (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
+ printk(KERN_ERR "EXT4-fs: Journal does not support "
+ "requested data journaling mode\n");
+ goto failed_mount4;
+ }
+ default:
+ break;
+ }
+
+ if (test_opt(sb, NOBH)) {
+ if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
+ printk(KERN_WARNING "EXT4-fs: Ignoring nobh option - "
+ "its supported only with writeback mode\n");
+ clear_opt(sbi->s_mount_opt, NOBH);
+ }
+ }
+ /*
+ * The jbd2_journal_load will have done any necessary log recovery,
+ * so we can safely mount the rest of the filesystem now.
+ */
+
+ root = iget(sb, EXT4_ROOT_INO);
+ sb->s_root = d_alloc_root(root);
+ if (!sb->s_root) {
+ printk(KERN_ERR "EXT4-fs: get root inode failed\n");
+ iput(root);
+ goto failed_mount4;
+ }
+ if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
+ dput(sb->s_root);
+ sb->s_root = NULL;
+ printk(KERN_ERR "EXT4-fs: corrupt root inode, run e2fsck\n");
+ goto failed_mount4;
+ }
+
+ ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY);
+ /*
+ * akpm: core read_super() calls in here with the superblock locked.
+ * That deadlocks, because orphan cleanup needs to lock the superblock
+ * in numerous places. Here we just pop the lock - it's relatively
+ * harmless, because we are now ready to accept write_super() requests,
+ * and aviro says that's the only reason for hanging onto the
+ * superblock lock.
+ */
+ EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
+ ext4_orphan_cleanup(sb, es);
+ EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
+ if (needs_recovery)
+ printk (KERN_INFO "EXT4-fs: recovery complete.\n");
+ ext4_mark_recovery_complete(sb, es);
+ printk (KERN_INFO "EXT4-fs: mounted filesystem with %s data mode.\n",
+ test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ? "journal":
+ test_opt(sb,DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA ? "ordered":
+ "writeback");
+
+ ext4_ext_init(sb);
+
+ lock_kernel();
+ return 0;
+
+cantfind_ext4:
+ if (!silent)
+ printk(KERN_ERR "VFS: Can't find ext4 filesystem on dev %s.\n",
+ sb->s_id);
+ goto failed_mount;
+
+failed_mount4:
+ jbd2_journal_destroy(sbi->s_journal);
+failed_mount3:
+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
+ percpu_counter_destroy(&sbi->s_dirs_counter);
+failed_mount2:
+ for (i = 0; i < db_count; i++)
+ brelse(sbi->s_group_desc[i]);
+ kfree(sbi->s_group_desc);
+failed_mount:
+#ifdef CONFIG_QUOTA
+ for (i = 0; i < MAXQUOTAS; i++)
+ kfree(sbi->s_qf_names[i]);
+#endif
+ ext4_blkdev_remove(sbi);
+ brelse(bh);
+out_fail:
+ sb->s_fs_info = NULL;
+ kfree(sbi);
+ lock_kernel();
+ return -EINVAL;
+}
+
+/*
+ * Setup any per-fs journal parameters now. We'll do this both on
+ * initial mount, once the journal has been initialised but before we've
+ * done any recovery; and again on any subsequent remount.
+ */
+static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+ if (sbi->s_commit_interval)
+ journal->j_commit_interval = sbi->s_commit_interval;
+ /* We could also set up an ext4-specific default for the commit
+ * interval here, but for now we'll just fall back to the jbd
+ * default. */
+
+ spin_lock(&journal->j_state_lock);
+ if (test_opt(sb, BARRIER))
+ journal->j_flags |= JBD2_BARRIER;
+ else
+ journal->j_flags &= ~JBD2_BARRIER;
+ spin_unlock(&journal->j_state_lock);
+}
+
+static journal_t *ext4_get_journal(struct super_block *sb,
+ unsigned int journal_inum)
+{
+ struct inode *journal_inode;
+ journal_t *journal;
+
+ /* First, test for the existence of a valid inode on disk. Bad
+ * things happen if we iget() an unused inode, as the subsequent
+ * iput() will try to delete it. */
+
+ journal_inode = iget(sb, journal_inum);
+ if (!journal_inode) {
+ printk(KERN_ERR "EXT4-fs: no journal found.\n");
+ return NULL;
+ }
+ if (!journal_inode->i_nlink) {
+ make_bad_inode(journal_inode);
+ iput(journal_inode);
+ printk(KERN_ERR "EXT4-fs: journal inode is deleted.\n");
+ return NULL;
+ }
+
+ jbd_debug(2, "Journal inode found at %p: %Ld bytes\n",
+ journal_inode, journal_inode->i_size);
+ if (is_bad_inode(journal_inode) || !S_ISREG(journal_inode->i_mode)) {
+ printk(KERN_ERR "EXT4-fs: invalid journal inode.\n");
+ iput(journal_inode);
+ return NULL;
+ }
+
+ journal = jbd2_journal_init_inode(journal_inode);
+ if (!journal) {
+ printk(KERN_ERR "EXT4-fs: Could not load journal inode\n");
+ iput(journal_inode);
+ return NULL;
+ }
+ journal->j_private = sb;
+ ext4_init_journal_params(sb, journal);
+ return journal;
+}
+
+static journal_t *ext4_get_dev_journal(struct super_block *sb,
+ dev_t j_dev)
+{
+ struct buffer_head * bh;
+ journal_t *journal;
+ ext4_fsblk_t start;
+ ext4_fsblk_t len;
+ int hblock, blocksize;
+ ext4_fsblk_t sb_block;
+ unsigned long offset;
+ struct ext4_super_block * es;
+ struct block_device *bdev;
+
+ bdev = ext4_blkdev_get(j_dev);
+ if (bdev == NULL)
+ return NULL;
+
+ if (bd_claim(bdev, sb)) {
+ printk(KERN_ERR
+ "EXT4: failed to claim external journal device.\n");
+ blkdev_put(bdev);
+ return NULL;
+ }
+
+ blocksize = sb->s_blocksize;
+ hblock = bdev_hardsect_size(bdev);
+ if (blocksize < hblock) {
+ printk(KERN_ERR
+ "EXT4-fs: blocksize too small for journal device.\n");
+ goto out_bdev;
+ }
+
+ sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
+ offset = EXT4_MIN_BLOCK_SIZE % blocksize;
+ set_blocksize(bdev, blocksize);
+ if (!(bh = __bread(bdev, sb_block, blocksize))) {
+ printk(KERN_ERR "EXT4-fs: couldn't read superblock of "
+ "external journal\n");
+ goto out_bdev;
+ }
+
+ es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
+ if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
+ !(le32_to_cpu(es->s_feature_incompat) &
+ EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
+ printk(KERN_ERR "EXT4-fs: external journal has "
+ "bad superblock\n");
+ brelse(bh);
+ goto out_bdev;
+ }
+
+ if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
+ printk(KERN_ERR "EXT4-fs: journal UUID does not match\n");
+ brelse(bh);
+ goto out_bdev;
+ }
+
+ len = ext4_blocks_count(es);
+ start = sb_block + 1;
+ brelse(bh); /* we're done with the superblock */
+
+ journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
+ start, len, blocksize);
+ if (!journal) {
+ printk(KERN_ERR "EXT4-fs: failed to create device journal\n");
+ goto out_bdev;
+ }
+ journal->j_private = sb;
+ ll_rw_block(READ, 1, &journal->j_sb_buffer);
+ wait_on_buffer(journal->j_sb_buffer);
+ if (!buffer_uptodate(journal->j_sb_buffer)) {
+ printk(KERN_ERR "EXT4-fs: I/O error on journal device\n");
+ goto out_journal;
+ }
+ if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
+ printk(KERN_ERR "EXT4-fs: External journal has more than one "
+ "user (unsupported) - %d\n",
+ be32_to_cpu(journal->j_superblock->s_nr_users));
+ goto out_journal;
+ }
+ EXT4_SB(sb)->journal_bdev = bdev;
+ ext4_init_journal_params(sb, journal);
+ return journal;
+out_journal:
+ jbd2_journal_destroy(journal);
+out_bdev:
+ ext4_blkdev_put(bdev);
+ return NULL;
+}
+
+static int ext4_load_journal(struct super_block *sb,
+ struct ext4_super_block *es,
+ unsigned long journal_devnum)
+{
+ journal_t *journal;
+ unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
+ dev_t journal_dev;
+ int err = 0;
+ int really_read_only;
+
+ if (journal_devnum &&
+ journal_devnum != le32_to_cpu(es->s_journal_dev)) {
+ printk(KERN_INFO "EXT4-fs: external journal device major/minor "
+ "numbers have changed\n");
+ journal_dev = new_decode_dev(journal_devnum);
+ } else
+ journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
+
+ really_read_only = bdev_read_only(sb->s_bdev);
+
+ /*
+ * Are we loading a blank journal or performing recovery after a
+ * crash? For recovery, we need to check in advance whether we
+ * can get read-write access to the device.
+ */
+
+ if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
+ if (sb->s_flags & MS_RDONLY) {
+ printk(KERN_INFO "EXT4-fs: INFO: recovery "
+ "required on readonly filesystem.\n");
+ if (really_read_only) {
+ printk(KERN_ERR "EXT4-fs: write access "
+ "unavailable, cannot proceed.\n");
+ return -EROFS;
+ }
+ printk (KERN_INFO "EXT4-fs: write access will "
+ "be enabled during recovery.\n");
+ }
+ }
+
+ if (journal_inum && journal_dev) {
+ printk(KERN_ERR "EXT4-fs: filesystem has both journal "
+ "and inode journals!\n");
+ return -EINVAL;
+ }
+
+ if (journal_inum) {
+ if (!(journal = ext4_get_journal(sb, journal_inum)))
+ return -EINVAL;
+ } else {
+ if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
+ return -EINVAL;
+ }
+
+ if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
+ err = jbd2_journal_update_format(journal);
+ if (err) {
+ printk(KERN_ERR "EXT4-fs: error updating journal.\n");
+ jbd2_journal_destroy(journal);
+ return err;
+ }
+ }
+
+ if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
+ err = jbd2_journal_wipe(journal, !really_read_only);
+ if (!err)
+ err = jbd2_journal_load(journal);
+
+ if (err) {
+ printk(KERN_ERR "EXT4-fs: error loading journal.\n");
+ jbd2_journal_destroy(journal);
+ return err;
+ }
+
+ EXT4_SB(sb)->s_journal = journal;
+ ext4_clear_journal_err(sb, es);
+
+ if (journal_devnum &&
+ journal_devnum != le32_to_cpu(es->s_journal_dev)) {
+ es->s_journal_dev = cpu_to_le32(journal_devnum);
+ sb->s_dirt = 1;
+
+ /* Make sure we flush the recovery flag to disk. */
+ ext4_commit_super(sb, es, 1);
+ }
+
+ return 0;
+}
+
+static int ext4_create_journal(struct super_block * sb,
+ struct ext4_super_block * es,
+ unsigned int journal_inum)
+{
+ journal_t *journal;
+
+ if (sb->s_flags & MS_RDONLY) {
+ printk(KERN_ERR "EXT4-fs: readonly filesystem when trying to "
+ "create journal.\n");
+ return -EROFS;
+ }
+
+ if (!(journal = ext4_get_journal(sb, journal_inum)))
+ return -EINVAL;
+
+ printk(KERN_INFO "EXT4-fs: creating new journal on inode %u\n",
+ journal_inum);
+
+ if (jbd2_journal_create(journal)) {
+ printk(KERN_ERR "EXT4-fs: error creating journal.\n");
+ jbd2_journal_destroy(journal);
+ return -EIO;
+ }
+
+ EXT4_SB(sb)->s_journal = journal;
+
+ ext4_update_dynamic_rev(sb);
+ EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+ EXT4_SET_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL);
+
+ es->s_journal_inum = cpu_to_le32(journal_inum);
+ sb->s_dirt = 1;
+
+ /* Make sure we flush the recovery flag to disk. */
+ ext4_commit_super(sb, es, 1);
+
+ return 0;
+}
+
+static void ext4_commit_super (struct super_block * sb,
+ struct ext4_super_block * es,
+ int sync)
+{
+ struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
+
+ if (!sbh)
+ return;
+ es->s_wtime = cpu_to_le32(get_seconds());
+ ext4_free_blocks_count_set(es, ext4_count_free_blocks(sb));
+ es->s_free_inodes_count = cpu_to_le32(ext4_count_free_inodes(sb));
+ BUFFER_TRACE(sbh, "marking dirty");
+ mark_buffer_dirty(sbh);
+ if (sync)
+ sync_dirty_buffer(sbh);
+}
+
+
+/*
+ * Have we just finished recovery? If so, and if we are mounting (or
+ * remounting) the filesystem readonly, then we will end up with a
+ * consistent fs on disk. Record that fact.
+ */
+static void ext4_mark_recovery_complete(struct super_block * sb,
+ struct ext4_super_block * es)
+{
+ journal_t *journal = EXT4_SB(sb)->s_journal;
+
+ jbd2_journal_lock_updates(journal);
+ jbd2_journal_flush(journal);
+ if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
+ sb->s_flags & MS_RDONLY) {
+ EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+ sb->s_dirt = 0;
+ ext4_commit_super(sb, es, 1);
+ }
+ jbd2_journal_unlock_updates(journal);
+}
+
+/*
+ * If we are mounting (or read-write remounting) a filesystem whose journal
+ * has recorded an error from a previous lifetime, move that error to the
+ * main filesystem now.
+ */
+static void ext4_clear_journal_err(struct super_block * sb,
+ struct ext4_super_block * es)
+{
+ journal_t *journal;
+ int j_errno;
+ const char *errstr;
+
+ journal = EXT4_SB(sb)->s_journal;
+
+ /*
+ * Now check for any error status which may have been recorded in the
+ * journal by a prior ext4_error() or ext4_abort()
+ */
+
+ j_errno = jbd2_journal_errno(journal);
+ if (j_errno) {
+ char nbuf[16];
+
+ errstr = ext4_decode_error(sb, j_errno, nbuf);
+ ext4_warning(sb, __FUNCTION__, "Filesystem error recorded "
+ "from previous mount: %s", errstr);
+ ext4_warning(sb, __FUNCTION__, "Marking fs in need of "
+ "filesystem check.");
+
+ EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
+ es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
+ ext4_commit_super (sb, es, 1);
+
+ jbd2_journal_clear_err(journal);
+ }
+}
+
+/*
+ * Force the running and committing transactions to commit,
+ * and wait on the commit.
+ */
+int ext4_force_commit(struct super_block *sb)
+{
+ journal_t *journal;
+ int ret;
+
+ if (sb->s_flags & MS_RDONLY)
+ return 0;
+
+ journal = EXT4_SB(sb)->s_journal;
+ sb->s_dirt = 0;
+ ret = ext4_journal_force_commit(journal);
+ return ret;
+}
+
+/*
+ * Ext4 always journals updates to the superblock itself, so we don't
+ * have to propagate any other updates to the superblock on disk at this
+ * point. Just start an async writeback to get the buffers on their way
+ * to the disk.
+ *
+ * This implicitly triggers the writebehind on sync().
+ */
+
+static void ext4_write_super (struct super_block * sb)
+{
+ if (mutex_trylock(&sb->s_lock) != 0)
+ BUG();
+ sb->s_dirt = 0;
+}
+
+static int ext4_sync_fs(struct super_block *sb, int wait)
+{
+ tid_t target;
+
+ sb->s_dirt = 0;
+ if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
+ if (wait)
+ jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
+ }
+ return 0;
+}
+
+/*
+ * LVM calls this function before a (read-only) snapshot is created. This
+ * gives us a chance to flush the journal completely and mark the fs clean.
+ */
+static void ext4_write_super_lockfs(struct super_block *sb)
+{
+ sb->s_dirt = 0;
+
+ if (!(sb->s_flags & MS_RDONLY)) {
+ journal_t *journal = EXT4_SB(sb)->s_journal;
+
+ /* Now we set up the journal barrier. */
+ jbd2_journal_lock_updates(journal);
+ jbd2_journal_flush(journal);
+
+ /* Journal blocked and flushed, clear needs_recovery flag. */
+ EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+ ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+ }
+}
+
+/*
+ * Called by LVM after the snapshot is done. We need to reset the RECOVER
+ * flag here, even though the filesystem is not technically dirty yet.
+ */
+static void ext4_unlockfs(struct super_block *sb)
+{
+ if (!(sb->s_flags & MS_RDONLY)) {
+ lock_super(sb);
+ /* Reser the needs_recovery flag before the fs is unlocked. */
+ EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
+ ext4_commit_super(sb, EXT4_SB(sb)->s_es, 1);
+ unlock_super(sb);
+ jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+ }
+}
+
+static int ext4_remount (struct super_block * sb, int * flags, char * data)
+{
+ struct ext4_super_block * es;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ ext4_fsblk_t n_blocks_count = 0;
+ unsigned long old_sb_flags;
+ struct ext4_mount_options old_opts;
+ int err;
+#ifdef CONFIG_QUOTA
+ int i;
+#endif
+
+ /* Store the original options */
+ old_sb_flags = sb->s_flags;
+ old_opts.s_mount_opt = sbi->s_mount_opt;
+ old_opts.s_resuid = sbi->s_resuid;
+ old_opts.s_resgid = sbi->s_resgid;
+ old_opts.s_commit_interval = sbi->s_commit_interval;
+#ifdef CONFIG_QUOTA
+ old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
+ for (i = 0; i < MAXQUOTAS; i++)
+ old_opts.s_qf_names[i] = sbi->s_qf_names[i];
+#endif
+
+ /*
+ * Allow the "check" option to be passed as a remount option.
+ */
+ if (!parse_options(data, sb, NULL, NULL, &n_blocks_count, 1)) {
+ err = -EINVAL;
+ goto restore_opts;
+ }
+
+ if (sbi->s_mount_opt & EXT4_MOUNT_ABORT)
+ ext4_abort(sb, __FUNCTION__, "Abort forced by user");
+
+ sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
+ ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
+
+ es = sbi->s_es;
+
+ ext4_init_journal_params(sb, sbi->s_journal);
+
+ if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
+ n_blocks_count > ext4_blocks_count(es)) {
+ if (sbi->s_mount_opt & EXT4_MOUNT_ABORT) {
+ err = -EROFS;
+ goto restore_opts;
+ }
+
+ if (*flags & MS_RDONLY) {
+ /*
+ * First of all, the unconditional stuff we have to do
+ * to disable replay of the journal when we next remount
+ */
+ sb->s_flags |= MS_RDONLY;
+
+ /*
+ * OK, test if we are remounting a valid rw partition
+ * readonly, and if so set the rdonly flag and then
+ * mark the partition as valid again.
+ */
+ if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
+ (sbi->s_mount_state & EXT4_VALID_FS))
+ es->s_state = cpu_to_le16(sbi->s_mount_state);
+
+ ext4_mark_recovery_complete(sb, es);
+ } else {
+ __le32 ret;
+ if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
+ printk(KERN_WARNING "EXT4-fs: %s: couldn't "
+ "remount RDWR because of unsupported "
+ "optional features (%x).\n",
+ sb->s_id, le32_to_cpu(ret));
+ err = -EROFS;
+ goto restore_opts;
+ }
+ /*
+ * Mounting a RDONLY partition read-write, so reread
+ * and store the current valid flag. (It may have
+ * been changed by e2fsck since we originally mounted
+ * the partition.)
+ */
+ ext4_clear_journal_err(sb, es);
+ sbi->s_mount_state = le16_to_cpu(es->s_state);
+ if ((err = ext4_group_extend(sb, es, n_blocks_count)))
+ goto restore_opts;
+ if (!ext4_setup_super (sb, es, 0))
+ sb->s_flags &= ~MS_RDONLY;
+ }
+ }
+#ifdef CONFIG_QUOTA
+ /* Release old quota file names */
+ for (i = 0; i < MAXQUOTAS; i++)
+ if (old_opts.s_qf_names[i] &&
+ old_opts.s_qf_names[i] != sbi->s_qf_names[i])
+ kfree(old_opts.s_qf_names[i]);
+#endif
+ return 0;
+restore_opts:
+ sb->s_flags = old_sb_flags;
+ sbi->s_mount_opt = old_opts.s_mount_opt;
+ sbi->s_resuid = old_opts.s_resuid;
+ sbi->s_resgid = old_opts.s_resgid;
+ sbi->s_commit_interval = old_opts.s_commit_interval;
+#ifdef CONFIG_QUOTA
+ sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
+ for (i = 0; i < MAXQUOTAS; i++) {
+ if (sbi->s_qf_names[i] &&
+ old_opts.s_qf_names[i] != sbi->s_qf_names[i])
+ kfree(sbi->s_qf_names[i]);
+ sbi->s_qf_names[i] = old_opts.s_qf_names[i];
+ }
+#endif
+ return err;
+}
+
+static int ext4_statfs (struct dentry * dentry, struct kstatfs * buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+ ext4_fsblk_t overhead;
+ int i;
+
+ if (test_opt (sb, MINIX_DF))
+ overhead = 0;
+ else {
+ unsigned long ngroups;
+ ngroups = EXT4_SB(sb)->s_groups_count;
+ smp_rmb();
+
+ /*
+ * Compute the overhead (FS structures)
+ */
+
+ /*
+ * All of the blocks before first_data_block are
+ * overhead
+ */
+ overhead = le32_to_cpu(es->s_first_data_block);
+
+ /*
+ * Add the overhead attributed to the superblock and
+ * block group descriptors. If the sparse superblocks
+ * feature is turned on, then not all groups have this.
+ */
+ for (i = 0; i < ngroups; i++) {
+ overhead += ext4_bg_has_super(sb, i) +
+ ext4_bg_num_gdb(sb, i);
+ cond_resched();
+ }
+
+ /*
+ * Every block group has an inode bitmap, a block
+ * bitmap, and an inode table.
+ */
+ overhead += (ngroups * (2 + EXT4_SB(sb)->s_itb_per_group));
+ }
+
+ buf->f_type = EXT4_SUPER_MAGIC;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_blocks = ext4_blocks_count(es) - overhead;
+ buf->f_bfree = percpu_counter_sum(&sbi->s_freeblocks_counter);
+ buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
+ if (buf->f_bfree < ext4_r_blocks_count(es))
+ buf->f_bavail = 0;
+ buf->f_files = le32_to_cpu(es->s_inodes_count);
+ buf->f_ffree = percpu_counter_sum(&sbi->s_freeinodes_counter);
+ buf->f_namelen = EXT4_NAME_LEN;
+ return 0;
+}
+
+/* Helper function for writing quotas on sync - we need to start transaction before quota file
+ * is locked for write. Otherwise the are possible deadlocks:
+ * Process 1 Process 2
+ * ext4_create() quota_sync()
+ * jbd2_journal_start() write_dquot()
+ * DQUOT_INIT() down(dqio_mutex)
+ * down(dqio_mutex) jbd2_journal_start()
+ *
+ */
+
+#ifdef CONFIG_QUOTA
+
+static inline struct inode *dquot_to_inode(struct dquot *dquot)
+{
+ return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
+}
+
+static int ext4_dquot_initialize(struct inode *inode, int type)
+{
+ handle_t *handle;
+ int ret, err;
+
+ /* We may create quota structure so we need to reserve enough blocks */
+ handle = ext4_journal_start(inode, 2*EXT4_QUOTA_INIT_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_initialize(inode, type);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+static int ext4_dquot_drop(struct inode *inode)
+{
+ handle_t *handle;
+ int ret, err;
+
+ /* We may delete quota structure so we need to reserve enough blocks */
+ handle = ext4_journal_start(inode, 2*EXT4_QUOTA_DEL_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_drop(inode);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+static int ext4_write_dquot(struct dquot *dquot)
+{
+ int ret, err;
+ handle_t *handle;
+ struct inode *inode;
+
+ inode = dquot_to_inode(dquot);
+ handle = ext4_journal_start(inode,
+ EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_commit(dquot);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+static int ext4_acquire_dquot(struct dquot *dquot)
+{
+ int ret, err;
+ handle_t *handle;
+
+ handle = ext4_journal_start(dquot_to_inode(dquot),
+ EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_acquire(dquot);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+static int ext4_release_dquot(struct dquot *dquot)
+{
+ int ret, err;
+ handle_t *handle;
+
+ handle = ext4_journal_start(dquot_to_inode(dquot),
+ EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_release(dquot);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+static int ext4_mark_dquot_dirty(struct dquot *dquot)
+{
+ /* Are we journalling quotas? */
+ if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
+ EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
+ dquot_mark_dquot_dirty(dquot);
+ return ext4_write_dquot(dquot);
+ } else {
+ return dquot_mark_dquot_dirty(dquot);
+ }
+}
+
+static int ext4_write_info(struct super_block *sb, int type)
+{
+ int ret, err;
+ handle_t *handle;
+
+ /* Data block + inode block */
+ handle = ext4_journal_start(sb->s_root->d_inode, 2);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+ ret = dquot_commit_info(sb, type);
+ err = ext4_journal_stop(handle);
+ if (!ret)
+ ret = err;
+ return ret;
+}
+
+/*
+ * Turn on quotas during mount time - we need to find
+ * the quota file and such...
+ */
+static int ext4_quota_on_mount(struct super_block *sb, int type)
+{
+ return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
+ EXT4_SB(sb)->s_jquota_fmt, type);
+}
+
+/*
+ * Standard function to be called on quota_on
+ */
+static int ext4_quota_on(struct super_block *sb, int type, int format_id,
+ char *path)
+{
+ int err;
+ struct nameidata nd;
+
+ if (!test_opt(sb, QUOTA))
+ return -EINVAL;
+ /* Not journalling quota? */
+ if (!EXT4_SB(sb)->s_qf_names[USRQUOTA] &&
+ !EXT4_SB(sb)->s_qf_names[GRPQUOTA])
+ return vfs_quota_on(sb, type, format_id, path);
+ err = path_lookup(path, LOOKUP_FOLLOW, &nd);
+ if (err)
+ return err;
+ /* Quotafile not on the same filesystem? */
+ if (nd.mnt->mnt_sb != sb) {
+ path_release(&nd);
+ return -EXDEV;
+ }
+ /* Quotafile not of fs root? */
+ if (nd.dentry->d_parent->d_inode != sb->s_root->d_inode)
+ printk(KERN_WARNING
+ "EXT4-fs: Quota file not on filesystem root. "
+ "Journalled quota will not work.\n");
+ path_release(&nd);
+ return vfs_quota_on(sb, type, format_id, path);
+}
+
+/* Read data from quotafile - avoid pagecache and such because we cannot afford
+ * acquiring the locks... As quota files are never truncated and quota code
+ * itself serializes the operations (and noone else should touch the files)
+ * we don't have to be afraid of races */
+static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
+ size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t toread;
+ struct buffer_head *bh;
+ loff_t i_size = i_size_read(inode);
+
+ if (off > i_size)
+ return 0;
+ if (off+len > i_size)
+ len = i_size-off;
+ toread = len;
+ while (toread > 0) {
+ tocopy = sb->s_blocksize - offset < toread ?
+ sb->s_blocksize - offset : toread;
+ bh = ext4_bread(NULL, inode, blk, 0, &err);
+ if (err)
+ return err;
+ if (!bh) /* A hole? */
+ memset(data, 0, tocopy);
+ else
+ memcpy(data, bh->b_data+offset, tocopy);
+ brelse(bh);
+ offset = 0;
+ toread -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+ return len;
+}
+
+/* Write to quotafile (we know the transaction is already started and has
+ * enough credits) */
+static ssize_t ext4_quota_write(struct super_block *sb, int type,
+ const char *data, size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
+ size_t towrite = len;
+ struct buffer_head *bh;
+ handle_t *handle = journal_current_handle();
+
+ mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
+ while (towrite > 0) {
+ tocopy = sb->s_blocksize - offset < towrite ?
+ sb->s_blocksize - offset : towrite;
+ bh = ext4_bread(handle, inode, blk, 1, &err);
+ if (!bh)
+ goto out;
+ if (journal_quota) {
+ err = ext4_journal_get_write_access(handle, bh);
+ if (err) {
+ brelse(bh);
+ goto out;
+ }
+ }
+ lock_buffer(bh);
+ memcpy(bh->b_data+offset, data, tocopy);
+ flush_dcache_page(bh->b_page);
+ unlock_buffer(bh);
+ if (journal_quota)
+ err = ext4_journal_dirty_metadata(handle, bh);
+ else {
+ /* Always do at least ordered writes for quotas */
+ err = ext4_journal_dirty_data(handle, bh);
+ mark_buffer_dirty(bh);
+ }
+ brelse(bh);
+ if (err)
+ goto out;
+ offset = 0;
+ towrite -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+out:
+ if (len == towrite)
+ return err;
+ if (inode->i_size < off+len-towrite) {
+ i_size_write(inode, off+len-towrite);
+ EXT4_I(inode)->i_disksize = inode->i_size;
+ }
+ inode->i_version++;
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ ext4_mark_inode_dirty(handle, inode);
+ mutex_unlock(&inode->i_mutex);
+ return len - towrite;
+}
+
+#endif
+
+static int ext4_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
+{
+ return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super, mnt);
+}
+
+static struct file_system_type ext4dev_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "ext4dev",
+ .get_sb = ext4_get_sb,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+static int __init init_ext4_fs(void)
+{
+ int err = init_ext4_xattr();
+ if (err)
+ return err;
+ err = init_inodecache();
+ if (err)
+ goto out1;
+ err = register_filesystem(&ext4dev_fs_type);
+ if (err)
+ goto out;
+ return 0;
+out:
+ destroy_inodecache();
+out1:
+ exit_ext4_xattr();
+ return err;
+}
+
+static void __exit exit_ext4_fs(void)
+{
+ unregister_filesystem(&ext4dev_fs_type);
+ destroy_inodecache();
+ exit_ext4_xattr();
+}
+
+MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
+MODULE_DESCRIPTION("Fourth Extended Filesystem with extents");
+MODULE_LICENSE("GPL");
+module_init(init_ext4_fs)
+module_exit(exit_ext4_fs)
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
new file mode 100644
index 000000000000..fcf527286d75
--- /dev/null
+++ b/fs/ext4/symlink.c
@@ -0,0 +1,54 @@
+/*
+ * linux/fs/ext4/symlink.c
+ *
+ * Only fast symlinks left here - the rest is done by generic code. AV, 1999
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ * from
+ *
+ * linux/fs/minix/symlink.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * ext4 symlink handling code
+ */
+
+#include <linux/fs.h>
+#include <linux/jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/namei.h>
+#include "xattr.h"
+
+static void * ext4_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct ext4_inode_info *ei = EXT4_I(dentry->d_inode);
+ nd_set_link(nd, (char*)ei->i_data);
+ return NULL;
+}
+
+struct inode_operations ext4_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = page_follow_link_light,
+ .put_link = page_put_link,
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = ext4_listxattr,
+ .removexattr = generic_removexattr,
+#endif
+};
+
+struct inode_operations ext4_fast_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = ext4_follow_link,
+#ifdef CONFIG_EXT4DEV_FS_XATTR
+ .setxattr = generic_setxattr,
+ .getxattr = generic_getxattr,
+ .listxattr = ext4_listxattr,
+ .removexattr = generic_removexattr,
+#endif
+};
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
new file mode 100644
index 000000000000..63233cd946a7
--- /dev/null
+++ b/fs/ext4/xattr.c
@@ -0,0 +1,1317 @@
+/*
+ * linux/fs/ext4/xattr.c
+ *
+ * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
+ *
+ * Fix by Harrison Xing <harrison@mountainviewdata.com>.
+ * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>.
+ * Extended attributes for symlinks and special files added per
+ * suggestion of Luka Renko <luka.renko@hermes.si>.
+ * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>,
+ * Red Hat Inc.
+ * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz
+ * and Andreas Gruenbacher <agruen@suse.de>.
+ */
+
+/*
+ * Extended attributes are stored directly in inodes (on file systems with
+ * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl
+ * field contains the block number if an inode uses an additional block. All
+ * attributes must fit in the inode and one additional block. Blocks that
+ * contain the identical set of attributes may be shared among several inodes.
+ * Identical blocks are detected by keeping a cache of blocks that have
+ * recently been accessed.
+ *
+ * The attributes in inodes and on blocks have a different header; the entries
+ * are stored in the same format:
+ *
+ * +------------------+
+ * | header |
+ * | entry 1 | |
+ * | entry 2 | | growing downwards
+ * | entry 3 | v
+ * | four null bytes |
+ * | . . . |
+ * | value 1 | ^
+ * | value 3 | | growing upwards
+ * | value 2 | |
+ * +------------------+
+ *
+ * The header is followed by multiple entry descriptors. In disk blocks, the
+ * entry descriptors are kept sorted. In inodes, they are unsorted. The
+ * attribute values are aligned to the end of the block in no specific order.
+ *
+ * Locking strategy
+ * ----------------
+ * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem.
+ * EA blocks are only changed if they are exclusive to an inode, so
+ * holding xattr_sem also means that nothing but the EA block's reference
+ * count can change. Multiple writers to the same block are synchronized
+ * by the buffer lock.
+ */
+
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/mbcache.h>
+#include <linux/quotaops.h>
+#include <linux/rwsem.h>
+#include "xattr.h"
+#include "acl.h"
+
+#define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data))
+#define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr))
+#define BFIRST(bh) ENTRY(BHDR(bh)+1)
+#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)
+
+#define IHDR(inode, raw_inode) \
+ ((struct ext4_xattr_ibody_header *) \
+ ((void *)raw_inode + \
+ EXT4_GOOD_OLD_INODE_SIZE + \
+ EXT4_I(inode)->i_extra_isize))
+#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1))
+
+#ifdef EXT4_XATTR_DEBUG
+# define ea_idebug(inode, f...) do { \
+ printk(KERN_DEBUG "inode %s:%lu: ", \
+ inode->i_sb->s_id, inode->i_ino); \
+ printk(f); \
+ printk("\n"); \
+ } while (0)
+# define ea_bdebug(bh, f...) do { \
+ char b[BDEVNAME_SIZE]; \
+ printk(KERN_DEBUG "block %s:%lu: ", \
+ bdevname(bh->b_bdev, b), \
+ (unsigned long) bh->b_blocknr); \
+ printk(f); \
+ printk("\n"); \
+ } while (0)
+#else
+# define ea_idebug(f...)
+# define ea_bdebug(f...)
+#endif
+
+static void ext4_xattr_cache_insert(struct buffer_head *);
+static struct buffer_head *ext4_xattr_cache_find(struct inode *,
+ struct ext4_xattr_header *,
+ struct mb_cache_entry **);
+static void ext4_xattr_rehash(struct ext4_xattr_header *,
+ struct ext4_xattr_entry *);
+
+static struct mb_cache *ext4_xattr_cache;
+
+static struct xattr_handler *ext4_xattr_handler_map[] = {
+ [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler,
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &ext4_xattr_acl_access_handler,
+ [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &ext4_xattr_acl_default_handler,
+#endif
+ [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler,
+#ifdef CONFIG_EXT4DEV_FS_SECURITY
+ [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler,
+#endif
+};
+
+struct xattr_handler *ext4_xattr_handlers[] = {
+ &ext4_xattr_user_handler,
+ &ext4_xattr_trusted_handler,
+#ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
+ &ext4_xattr_acl_access_handler,
+ &ext4_xattr_acl_default_handler,
+#endif
+#ifdef CONFIG_EXT4DEV_FS_SECURITY
+ &ext4_xattr_security_handler,
+#endif
+ NULL
+};
+
+static inline struct xattr_handler *
+ext4_xattr_handler(int name_index)
+{
+ struct xattr_handler *handler = NULL;
+
+ if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map))
+ handler = ext4_xattr_handler_map[name_index];
+ return handler;
+}
+
+/*
+ * Inode operation listxattr()
+ *
+ * dentry->d_inode->i_mutex: don't care
+ */
+ssize_t
+ext4_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+ return ext4_xattr_list(dentry->d_inode, buffer, size);
+}
+
+static int
+ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end)
+{
+ while (!IS_LAST_ENTRY(entry)) {
+ struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(entry);
+ if ((void *)next >= end)
+ return -EIO;
+ entry = next;
+ }
+ return 0;
+}
+
+static inline int
+ext4_xattr_check_block(struct buffer_head *bh)
+{
+ int error;
+
+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
+ BHDR(bh)->h_blocks != cpu_to_le32(1))
+ return -EIO;
+ error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size);
+ return error;
+}
+
+static inline int
+ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size)
+{
+ size_t value_size = le32_to_cpu(entry->e_value_size);
+
+ if (entry->e_value_block != 0 || value_size > size ||
+ le16_to_cpu(entry->e_value_offs) + value_size > size)
+ return -EIO;
+ return 0;
+}
+
+static int
+ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index,
+ const char *name, size_t size, int sorted)
+{
+ struct ext4_xattr_entry *entry;
+ size_t name_len;
+ int cmp = 1;
+
+ if (name == NULL)
+ return -EINVAL;
+ name_len = strlen(name);
+ entry = *pentry;
+ for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
+ cmp = name_index - entry->e_name_index;
+ if (!cmp)
+ cmp = name_len - entry->e_name_len;
+ if (!cmp)
+ cmp = memcmp(name, entry->e_name, name_len);
+ if (cmp <= 0 && (sorted || cmp == 0))
+ break;
+ }
+ *pentry = entry;
+ if (!cmp && ext4_xattr_check_entry(entry, size))
+ return -EIO;
+ return cmp ? -ENODATA : 0;
+}
+
+static int
+ext4_xattr_block_get(struct inode *inode, int name_index, const char *name,
+ void *buffer, size_t buffer_size)
+{
+ struct buffer_head *bh = NULL;
+ struct ext4_xattr_entry *entry;
+ size_t size;
+ int error;
+
+ ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
+ name_index, name, buffer, (long)buffer_size);
+
+ error = -ENODATA;
+ if (!EXT4_I(inode)->i_file_acl)
+ goto cleanup;
+ ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl);
+ bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
+ if (!bh)
+ goto cleanup;
+ ea_bdebug(bh, "b_count=%d, refcount=%d",
+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
+ if (ext4_xattr_check_block(bh)) {
+bad_block: ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: bad block %llu", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ error = -EIO;
+ goto cleanup;
+ }
+ ext4_xattr_cache_insert(bh);
+ entry = BFIRST(bh);
+ error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1);
+ if (error == -EIO)
+ goto bad_block;
+ if (error)
+ goto cleanup;
+ size = le32_to_cpu(entry->e_value_size);
+ if (buffer) {
+ error = -ERANGE;
+ if (size > buffer_size)
+ goto cleanup;
+ memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs),
+ size);
+ }
+ error = size;
+
+cleanup:
+ brelse(bh);
+ return error;
+}
+
+static int
+ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name,
+ void *buffer, size_t buffer_size)
+{
+ struct ext4_xattr_ibody_header *header;
+ struct ext4_xattr_entry *entry;
+ struct ext4_inode *raw_inode;
+ struct ext4_iloc iloc;
+ size_t size;
+ void *end;
+ int error;
+
+ if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR))
+ return -ENODATA;
+ error = ext4_get_inode_loc(inode, &iloc);
+ if (error)
+ return error;
+ raw_inode = ext4_raw_inode(&iloc);
+ header = IHDR(inode, raw_inode);
+ entry = IFIRST(header);
+ end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
+ error = ext4_xattr_check_names(entry, end);
+ if (error)
+ goto cleanup;
+ error = ext4_xattr_find_entry(&entry, name_index, name,
+ end - (void *)entry, 0);
+ if (error)
+ goto cleanup;
+ size = le32_to_cpu(entry->e_value_size);
+ if (buffer) {
+ error = -ERANGE;
+ if (size > buffer_size)
+ goto cleanup;
+ memcpy(buffer, (void *)IFIRST(header) +
+ le16_to_cpu(entry->e_value_offs), size);
+ }
+ error = size;
+
+cleanup:
+ brelse(iloc.bh);
+ return error;
+}
+
+/*
+ * ext4_xattr_get()
+ *
+ * Copy an extended attribute into the buffer
+ * provided, or compute the buffer size required.
+ * Buffer is NULL to compute the size of the buffer required.
+ *
+ * Returns a negative error number on failure, or the number of bytes
+ * used / required on success.
+ */
+int
+ext4_xattr_get(struct inode *inode, int name_index, const char *name,
+ void *buffer, size_t buffer_size)
+{
+ int error;
+
+ down_read(&EXT4_I(inode)->xattr_sem);
+ error = ext4_xattr_ibody_get(inode, name_index, name, buffer,
+ buffer_size);
+ if (error == -ENODATA)
+ error = ext4_xattr_block_get(inode, name_index, name, buffer,
+ buffer_size);
+ up_read(&EXT4_I(inode)->xattr_sem);
+ return error;
+}
+
+static int
+ext4_xattr_list_entries(struct inode *inode, struct ext4_xattr_entry *entry,
+ char *buffer, size_t buffer_size)
+{
+ size_t rest = buffer_size;
+
+ for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
+ struct xattr_handler *handler =
+ ext4_xattr_handler(entry->e_name_index);
+
+ if (handler) {
+ size_t size = handler->list(inode, buffer, rest,
+ entry->e_name,
+ entry->e_name_len);
+ if (buffer) {
+ if (size > rest)
+ return -ERANGE;
+ buffer += size;
+ }
+ rest -= size;
+ }
+ }
+ return buffer_size - rest;
+}
+
+static int
+ext4_xattr_block_list(struct inode *inode, char *buffer, size_t buffer_size)
+{
+ struct buffer_head *bh = NULL;
+ int error;
+
+ ea_idebug(inode, "buffer=%p, buffer_size=%ld",
+ buffer, (long)buffer_size);
+
+ error = 0;
+ if (!EXT4_I(inode)->i_file_acl)
+ goto cleanup;
+ ea_idebug(inode, "reading block %u", EXT4_I(inode)->i_file_acl);
+ bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
+ error = -EIO;
+ if (!bh)
+ goto cleanup;
+ ea_bdebug(bh, "b_count=%d, refcount=%d",
+ atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount));
+ if (ext4_xattr_check_block(bh)) {
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: bad block %llu", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ error = -EIO;
+ goto cleanup;
+ }
+ ext4_xattr_cache_insert(bh);
+ error = ext4_xattr_list_entries(inode, BFIRST(bh), buffer, buffer_size);
+
+cleanup:
+ brelse(bh);
+
+ return error;
+}
+
+static int
+ext4_xattr_ibody_list(struct inode *inode, char *buffer, size_t buffer_size)
+{
+ struct ext4_xattr_ibody_header *header;
+ struct ext4_inode *raw_inode;
+ struct ext4_iloc iloc;
+ void *end;
+ int error;
+
+ if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR))
+ return 0;
+ error = ext4_get_inode_loc(inode, &iloc);
+ if (error)
+ return error;
+ raw_inode = ext4_raw_inode(&iloc);
+ header = IHDR(inode, raw_inode);
+ end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
+ error = ext4_xattr_check_names(IFIRST(header), end);
+ if (error)
+ goto cleanup;
+ error = ext4_xattr_list_entries(inode, IFIRST(header),
+ buffer, buffer_size);
+
+cleanup:
+ brelse(iloc.bh);
+ return error;
+}
+
+/*
+ * ext4_xattr_list()
+ *
+ * Copy a list of attribute names into the buffer
+ * provided, or compute the buffer size required.
+ * Buffer is NULL to compute the size of the buffer required.
+ *
+ * Returns a negative error number on failure, or the number of bytes
+ * used / required on success.
+ */
+int
+ext4_xattr_list(struct inode *inode, char *buffer, size_t buffer_size)
+{
+ int i_error, b_error;
+
+ down_read(&EXT4_I(inode)->xattr_sem);
+ i_error = ext4_xattr_ibody_list(inode, buffer, buffer_size);
+ if (i_error < 0) {
+ b_error = 0;
+ } else {
+ if (buffer) {
+ buffer += i_error;
+ buffer_size -= i_error;
+ }
+ b_error = ext4_xattr_block_list(inode, buffer, buffer_size);
+ if (b_error < 0)
+ i_error = 0;
+ }
+ up_read(&EXT4_I(inode)->xattr_sem);
+ return i_error + b_error;
+}
+
+/*
+ * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is
+ * not set, set it.
+ */
+static void ext4_xattr_update_super_block(handle_t *handle,
+ struct super_block *sb)
+{
+ if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_EXT_ATTR))
+ return;
+
+ lock_super(sb);
+ if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) {
+ EXT4_SB(sb)->s_es->s_feature_compat |=
+ cpu_to_le32(EXT4_FEATURE_COMPAT_EXT_ATTR);
+ sb->s_dirt = 1;
+ ext4_journal_dirty_metadata(handle, EXT4_SB(sb)->s_sbh);
+ }
+ unlock_super(sb);
+}
+
+/*
+ * Release the xattr block BH: If the reference count is > 1, decrement
+ * it; otherwise free the block.
+ */
+static void
+ext4_xattr_release_block(handle_t *handle, struct inode *inode,
+ struct buffer_head *bh)
+{
+ struct mb_cache_entry *ce = NULL;
+
+ ce = mb_cache_entry_get(ext4_xattr_cache, bh->b_bdev, bh->b_blocknr);
+ if (BHDR(bh)->h_refcount == cpu_to_le32(1)) {
+ ea_bdebug(bh, "refcount now=0; freeing");
+ if (ce)
+ mb_cache_entry_free(ce);
+ ext4_free_blocks(handle, inode, bh->b_blocknr, 1);
+ get_bh(bh);
+ ext4_forget(handle, 1, inode, bh, bh->b_blocknr);
+ } else {
+ if (ext4_journal_get_write_access(handle, bh) == 0) {
+ lock_buffer(bh);
+ BHDR(bh)->h_refcount = cpu_to_le32(
+ le32_to_cpu(BHDR(bh)->h_refcount) - 1);
+ ext4_journal_dirty_metadata(handle, bh);
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+ DQUOT_FREE_BLOCK(inode, 1);
+ unlock_buffer(bh);
+ ea_bdebug(bh, "refcount now=%d; releasing",
+ le32_to_cpu(BHDR(bh)->h_refcount));
+ }
+ if (ce)
+ mb_cache_entry_release(ce);
+ }
+}
+
+struct ext4_xattr_info {
+ int name_index;
+ const char *name;
+ const void *value;
+ size_t value_len;
+};
+
+struct ext4_xattr_search {
+ struct ext4_xattr_entry *first;
+ void *base;
+ void *end;
+ struct ext4_xattr_entry *here;
+ int not_found;
+};
+
+static int
+ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s)
+{
+ struct ext4_xattr_entry *last;
+ size_t free, min_offs = s->end - s->base, name_len = strlen(i->name);
+
+ /* Compute min_offs and last. */
+ last = s->first;
+ for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) {
+ if (!last->e_value_block && last->e_value_size) {
+ size_t offs = le16_to_cpu(last->e_value_offs);
+ if (offs < min_offs)
+ min_offs = offs;
+ }
+ }
+ free = min_offs - ((void *)last - s->base) - sizeof(__u32);
+ if (!s->not_found) {
+ if (!s->here->e_value_block && s->here->e_value_size) {
+ size_t size = le32_to_cpu(s->here->e_value_size);
+ free += EXT4_XATTR_SIZE(size);
+ }
+ free += EXT4_XATTR_LEN(name_len);
+ }
+ if (i->value) {
+ if (free < EXT4_XATTR_SIZE(i->value_len) ||
+ free < EXT4_XATTR_LEN(name_len) +
+ EXT4_XATTR_SIZE(i->value_len))
+ return -ENOSPC;
+ }
+
+ if (i->value && s->not_found) {
+ /* Insert the new name. */
+ size_t size = EXT4_XATTR_LEN(name_len);
+ size_t rest = (void *)last - (void *)s->here + sizeof(__u32);
+ memmove((void *)s->here + size, s->here, rest);
+ memset(s->here, 0, size);
+ s->here->e_name_index = i->name_index;
+ s->here->e_name_len = name_len;
+ memcpy(s->here->e_name, i->name, name_len);
+ } else {
+ if (!s->here->e_value_block && s->here->e_value_size) {
+ void *first_val = s->base + min_offs;
+ size_t offs = le16_to_cpu(s->here->e_value_offs);
+ void *val = s->base + offs;
+ size_t size = EXT4_XATTR_SIZE(
+ le32_to_cpu(s->here->e_value_size));
+
+ if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) {
+ /* The old and the new value have the same
+ size. Just replace. */
+ s->here->e_value_size =
+ cpu_to_le32(i->value_len);
+ memset(val + size - EXT4_XATTR_PAD, 0,
+ EXT4_XATTR_PAD); /* Clear pad bytes. */
+ memcpy(val, i->value, i->value_len);
+ return 0;
+ }
+
+ /* Remove the old value. */
+ memmove(first_val + size, first_val, val - first_val);
+ memset(first_val, 0, size);
+ s->here->e_value_size = 0;
+ s->here->e_value_offs = 0;
+ min_offs += size;
+
+ /* Adjust all value offsets. */
+ last = s->first;
+ while (!IS_LAST_ENTRY(last)) {
+ size_t o = le16_to_cpu(last->e_value_offs);
+ if (!last->e_value_block &&
+ last->e_value_size && o < offs)
+ last->e_value_offs =
+ cpu_to_le16(o + size);
+ last = EXT4_XATTR_NEXT(last);
+ }
+ }
+ if (!i->value) {
+ /* Remove the old name. */
+ size_t size = EXT4_XATTR_LEN(name_len);
+ last = ENTRY((void *)last - size);
+ memmove(s->here, (void *)s->here + size,
+ (void *)last - (void *)s->here + sizeof(__u32));
+ memset(last, 0, size);
+ }
+ }
+
+ if (i->value) {
+ /* Insert the new value. */
+ s->here->e_value_size = cpu_to_le32(i->value_len);
+ if (i->value_len) {
+ size_t size = EXT4_XATTR_SIZE(i->value_len);
+ void *val = s->base + min_offs - size;
+ s->here->e_value_offs = cpu_to_le16(min_offs - size);
+ memset(val + size - EXT4_XATTR_PAD, 0,
+ EXT4_XATTR_PAD); /* Clear the pad bytes. */
+ memcpy(val, i->value, i->value_len);
+ }
+ }
+ return 0;
+}
+
+struct ext4_xattr_block_find {
+ struct ext4_xattr_search s;
+ struct buffer_head *bh;
+};
+
+static int
+ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i,
+ struct ext4_xattr_block_find *bs)
+{
+ struct super_block *sb = inode->i_sb;
+ int error;
+
+ ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld",
+ i->name_index, i->name, i->value, (long)i->value_len);
+
+ if (EXT4_I(inode)->i_file_acl) {
+ /* The inode already has an extended attribute block. */
+ bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl);
+ error = -EIO;
+ if (!bs->bh)
+ goto cleanup;
+ ea_bdebug(bs->bh, "b_count=%d, refcount=%d",
+ atomic_read(&(bs->bh->b_count)),
+ le32_to_cpu(BHDR(bs->bh)->h_refcount));
+ if (ext4_xattr_check_block(bs->bh)) {
+ ext4_error(sb, __FUNCTION__,
+ "inode %lu: bad block %llu", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ error = -EIO;
+ goto cleanup;
+ }
+ /* Find the named attribute. */
+ bs->s.base = BHDR(bs->bh);
+ bs->s.first = BFIRST(bs->bh);
+ bs->s.end = bs->bh->b_data + bs->bh->b_size;
+ bs->s.here = bs->s.first;
+ error = ext4_xattr_find_entry(&bs->s.here, i->name_index,
+ i->name, bs->bh->b_size, 1);
+ if (error && error != -ENODATA)
+ goto cleanup;
+ bs->s.not_found = error;
+ }
+ error = 0;
+
+cleanup:
+ return error;
+}
+
+static int
+ext4_xattr_block_set(handle_t *handle, struct inode *inode,
+ struct ext4_xattr_info *i,
+ struct ext4_xattr_block_find *bs)
+{
+ struct super_block *sb = inode->i_sb;
+ struct buffer_head *new_bh = NULL;
+ struct ext4_xattr_search *s = &bs->s;
+ struct mb_cache_entry *ce = NULL;
+ int error;
+
+#define header(x) ((struct ext4_xattr_header *)(x))
+
+ if (i->value && i->value_len > sb->s_blocksize)
+ return -ENOSPC;
+ if (s->base) {
+ ce = mb_cache_entry_get(ext4_xattr_cache, bs->bh->b_bdev,
+ bs->bh->b_blocknr);
+ if (header(s->base)->h_refcount == cpu_to_le32(1)) {
+ if (ce) {
+ mb_cache_entry_free(ce);
+ ce = NULL;
+ }
+ ea_bdebug(bs->bh, "modifying in-place");
+ error = ext4_journal_get_write_access(handle, bs->bh);
+ if (error)
+ goto cleanup;
+ lock_buffer(bs->bh);
+ error = ext4_xattr_set_entry(i, s);
+ if (!error) {
+ if (!IS_LAST_ENTRY(s->first))
+ ext4_xattr_rehash(header(s->base),
+ s->here);
+ ext4_xattr_cache_insert(bs->bh);
+ }
+ unlock_buffer(bs->bh);
+ if (error == -EIO)
+ goto bad_block;
+ if (!error)
+ error = ext4_journal_dirty_metadata(handle,
+ bs->bh);
+ if (error)
+ goto cleanup;
+ goto inserted;
+ } else {
+ int offset = (char *)s->here - bs->bh->b_data;
+
+ if (ce) {
+ mb_cache_entry_release(ce);
+ ce = NULL;
+ }
+ ea_bdebug(bs->bh, "cloning");
+ s->base = kmalloc(bs->bh->b_size, GFP_KERNEL);
+ error = -ENOMEM;
+ if (s->base == NULL)
+ goto cleanup;
+ memcpy(s->base, BHDR(bs->bh), bs->bh->b_size);
+ s->first = ENTRY(header(s->base)+1);
+ header(s->base)->h_refcount = cpu_to_le32(1);
+ s->here = ENTRY(s->base + offset);
+ s->end = s->base + bs->bh->b_size;
+ }
+ } else {
+ /* Allocate a buffer where we construct the new block. */
+ s->base = kmalloc(sb->s_blocksize, GFP_KERNEL);
+ /* assert(header == s->base) */
+ error = -ENOMEM;
+ if (s->base == NULL)
+ goto cleanup;
+ memset(s->base, 0, sb->s_blocksize);
+ header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
+ header(s->base)->h_blocks = cpu_to_le32(1);
+ header(s->base)->h_refcount = cpu_to_le32(1);
+ s->first = ENTRY(header(s->base)+1);
+ s->here = ENTRY(header(s->base)+1);
+ s->end = s->base + sb->s_blocksize;
+ }
+
+ error = ext4_xattr_set_entry(i, s);
+ if (error == -EIO)
+ goto bad_block;
+ if (error)
+ goto cleanup;
+ if (!IS_LAST_ENTRY(s->first))
+ ext4_xattr_rehash(header(s->base), s->here);
+
+inserted:
+ if (!IS_LAST_ENTRY(s->first)) {
+ new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce);
+ if (new_bh) {
+ /* We found an identical block in the cache. */
+ if (new_bh == bs->bh)
+ ea_bdebug(new_bh, "keeping");
+ else {
+ /* The old block is released after updating
+ the inode. */
+ error = -EDQUOT;
+ if (DQUOT_ALLOC_BLOCK(inode, 1))
+ goto cleanup;
+ error = ext4_journal_get_write_access(handle,
+ new_bh);
+ if (error)
+ goto cleanup_dquot;
+ lock_buffer(new_bh);
+ BHDR(new_bh)->h_refcount = cpu_to_le32(1 +
+ le32_to_cpu(BHDR(new_bh)->h_refcount));
+ ea_bdebug(new_bh, "reusing; refcount now=%d",
+ le32_to_cpu(BHDR(new_bh)->h_refcount));
+ unlock_buffer(new_bh);
+ error = ext4_journal_dirty_metadata(handle,
+ new_bh);
+ if (error)
+ goto cleanup_dquot;
+ }
+ mb_cache_entry_release(ce);
+ ce = NULL;
+ } else if (bs->bh && s->base == bs->bh->b_data) {
+ /* We were modifying this block in-place. */
+ ea_bdebug(bs->bh, "keeping this block");
+ new_bh = bs->bh;
+ get_bh(new_bh);
+ } else {
+ /* We need to allocate a new block */
+ ext4_fsblk_t goal = le32_to_cpu(
+ EXT4_SB(sb)->s_es->s_first_data_block) +
+ (ext4_fsblk_t)EXT4_I(inode)->i_block_group *
+ EXT4_BLOCKS_PER_GROUP(sb);
+ ext4_fsblk_t block = ext4_new_block(handle, inode,
+ goal, &error);
+ if (error)
+ goto cleanup;
+ ea_idebug(inode, "creating block %d", block);
+
+ new_bh = sb_getblk(sb, block);
+ if (!new_bh) {
+getblk_failed:
+ ext4_free_blocks(handle, inode, block, 1);
+ error = -EIO;
+ goto cleanup;
+ }
+ lock_buffer(new_bh);
+ error = ext4_journal_get_create_access(handle, new_bh);
+ if (error) {
+ unlock_buffer(new_bh);
+ goto getblk_failed;
+ }
+ memcpy(new_bh->b_data, s->base, new_bh->b_size);
+ set_buffer_uptodate(new_bh);
+ unlock_buffer(new_bh);
+ ext4_xattr_cache_insert(new_bh);
+ error = ext4_journal_dirty_metadata(handle, new_bh);
+ if (error)
+ goto cleanup;
+ }
+ }
+
+ /* Update the inode. */
+ EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0;
+
+ /* Drop the previous xattr block. */
+ if (bs->bh && bs->bh != new_bh)
+ ext4_xattr_release_block(handle, inode, bs->bh);
+ error = 0;
+
+cleanup:
+ if (ce)
+ mb_cache_entry_release(ce);
+ brelse(new_bh);
+ if (!(bs->bh && s->base == bs->bh->b_data))
+ kfree(s->base);
+
+ return error;
+
+cleanup_dquot:
+ DQUOT_FREE_BLOCK(inode, 1);
+ goto cleanup;
+
+bad_block:
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: bad block %llu", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ goto cleanup;
+
+#undef header
+}
+
+struct ext4_xattr_ibody_find {
+ struct ext4_xattr_search s;
+ struct ext4_iloc iloc;
+};
+
+static int
+ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i,
+ struct ext4_xattr_ibody_find *is)
+{
+ struct ext4_xattr_ibody_header *header;
+ struct ext4_inode *raw_inode;
+ int error;
+
+ if (EXT4_I(inode)->i_extra_isize == 0)
+ return 0;
+ raw_inode = ext4_raw_inode(&is->iloc);
+ header = IHDR(inode, raw_inode);
+ is->s.base = is->s.first = IFIRST(header);
+ is->s.here = is->s.first;
+ is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size;
+ if (EXT4_I(inode)->i_state & EXT4_STATE_XATTR) {
+ error = ext4_xattr_check_names(IFIRST(header), is->s.end);
+ if (error)
+ return error;
+ /* Find the named attribute. */
+ error = ext4_xattr_find_entry(&is->s.here, i->name_index,
+ i->name, is->s.end -
+ (void *)is->s.base, 0);
+ if (error && error != -ENODATA)
+ return error;
+ is->s.not_found = error;
+ }
+ return 0;
+}
+
+static int
+ext4_xattr_ibody_set(handle_t *handle, struct inode *inode,
+ struct ext4_xattr_info *i,
+ struct ext4_xattr_ibody_find *is)
+{
+ struct ext4_xattr_ibody_header *header;
+ struct ext4_xattr_search *s = &is->s;
+ int error;
+
+ if (EXT4_I(inode)->i_extra_isize == 0)
+ return -ENOSPC;
+ error = ext4_xattr_set_entry(i, s);
+ if (error)
+ return error;
+ header = IHDR(inode, ext4_raw_inode(&is->iloc));
+ if (!IS_LAST_ENTRY(s->first)) {
+ header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC);
+ EXT4_I(inode)->i_state |= EXT4_STATE_XATTR;
+ } else {
+ header->h_magic = cpu_to_le32(0);
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_XATTR;
+ }
+ return 0;
+}
+
+/*
+ * ext4_xattr_set_handle()
+ *
+ * Create, replace or remove an extended attribute for this inode. Buffer
+ * is NULL to remove an existing extended attribute, and non-NULL to
+ * either replace an existing extended attribute, or create a new extended
+ * attribute. The flags XATTR_REPLACE and XATTR_CREATE
+ * specify that an extended attribute must exist and must not exist
+ * previous to the call, respectively.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+int
+ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
+ const char *name, const void *value, size_t value_len,
+ int flags)
+{
+ struct ext4_xattr_info i = {
+ .name_index = name_index,
+ .name = name,
+ .value = value,
+ .value_len = value_len,
+
+ };
+ struct ext4_xattr_ibody_find is = {
+ .s = { .not_found = -ENODATA, },
+ };
+ struct ext4_xattr_block_find bs = {
+ .s = { .not_found = -ENODATA, },
+ };
+ int error;
+
+ if (!name)
+ return -EINVAL;
+ if (strlen(name) > 255)
+ return -ERANGE;
+ down_write(&EXT4_I(inode)->xattr_sem);
+ error = ext4_get_inode_loc(inode, &is.iloc);
+ if (error)
+ goto cleanup;
+
+ if (EXT4_I(inode)->i_state & EXT4_STATE_NEW) {
+ struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc);
+ memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size);
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_NEW;
+ }
+
+ error = ext4_xattr_ibody_find(inode, &i, &is);
+ if (error)
+ goto cleanup;
+ if (is.s.not_found)
+ error = ext4_xattr_block_find(inode, &i, &bs);
+ if (error)
+ goto cleanup;
+ if (is.s.not_found && bs.s.not_found) {
+ error = -ENODATA;
+ if (flags & XATTR_REPLACE)
+ goto cleanup;
+ error = 0;
+ if (!value)
+ goto cleanup;
+ } else {
+ error = -EEXIST;
+ if (flags & XATTR_CREATE)
+ goto cleanup;
+ }
+ error = ext4_journal_get_write_access(handle, is.iloc.bh);
+ if (error)
+ goto cleanup;
+ if (!value) {
+ if (!is.s.not_found)
+ error = ext4_xattr_ibody_set(handle, inode, &i, &is);
+ else if (!bs.s.not_found)
+ error = ext4_xattr_block_set(handle, inode, &i, &bs);
+ } else {
+ error = ext4_xattr_ibody_set(handle, inode, &i, &is);
+ if (!error && !bs.s.not_found) {
+ i.value = NULL;
+ error = ext4_xattr_block_set(handle, inode, &i, &bs);
+ } else if (error == -ENOSPC) {
+ error = ext4_xattr_block_set(handle, inode, &i, &bs);
+ if (error)
+ goto cleanup;
+ if (!is.s.not_found) {
+ i.value = NULL;
+ error = ext4_xattr_ibody_set(handle, inode, &i,
+ &is);
+ }
+ }
+ }
+ if (!error) {
+ ext4_xattr_update_super_block(handle, inode->i_sb);
+ inode->i_ctime = CURRENT_TIME_SEC;
+ error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
+ /*
+ * The bh is consumed by ext4_mark_iloc_dirty, even with
+ * error != 0.
+ */
+ is.iloc.bh = NULL;
+ if (IS_SYNC(inode))
+ handle->h_sync = 1;
+ }
+
+cleanup:
+ brelse(is.iloc.bh);
+ brelse(bs.bh);
+ up_write(&EXT4_I(inode)->xattr_sem);
+ return error;
+}
+
+/*
+ * ext4_xattr_set()
+ *
+ * Like ext4_xattr_set_handle, but start from an inode. This extended
+ * attribute modification is a filesystem transaction by itself.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+int
+ext4_xattr_set(struct inode *inode, int name_index, const char *name,
+ const void *value, size_t value_len, int flags)
+{
+ handle_t *handle;
+ int error, retries = 0;
+
+retry:
+ handle = ext4_journal_start(inode, EXT4_DATA_TRANS_BLOCKS(inode->i_sb));
+ if (IS_ERR(handle)) {
+ error = PTR_ERR(handle);
+ } else {
+ int error2;
+
+ error = ext4_xattr_set_handle(handle, inode, name_index, name,
+ value, value_len, flags);
+ error2 = ext4_journal_stop(handle);
+ if (error == -ENOSPC &&
+ ext4_should_retry_alloc(inode->i_sb, &retries))
+ goto retry;
+ if (error == 0)
+ error = error2;
+ }
+
+ return error;
+}
+
+/*
+ * ext4_xattr_delete_inode()
+ *
+ * Free extended attribute resources associated with this inode. This
+ * is called immediately before an inode is freed. We have exclusive
+ * access to the inode.
+ */
+void
+ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
+{
+ struct buffer_head *bh = NULL;
+
+ if (!EXT4_I(inode)->i_file_acl)
+ goto cleanup;
+ bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl);
+ if (!bh) {
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: block %llu read error", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ goto cleanup;
+ }
+ if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) ||
+ BHDR(bh)->h_blocks != cpu_to_le32(1)) {
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: bad block %llu", inode->i_ino,
+ EXT4_I(inode)->i_file_acl);
+ goto cleanup;
+ }
+ ext4_xattr_release_block(handle, inode, bh);
+ EXT4_I(inode)->i_file_acl = 0;
+
+cleanup:
+ brelse(bh);
+}
+
+/*
+ * ext4_xattr_put_super()
+ *
+ * This is called when a file system is unmounted.
+ */
+void
+ext4_xattr_put_super(struct super_block *sb)
+{
+ mb_cache_shrink(sb->s_bdev);
+}
+
+/*
+ * ext4_xattr_cache_insert()
+ *
+ * Create a new entry in the extended attribute cache, and insert
+ * it unless such an entry is already in the cache.
+ *
+ * Returns 0, or a negative error number on failure.
+ */
+static void
+ext4_xattr_cache_insert(struct buffer_head *bh)
+{
+ __u32 hash = le32_to_cpu(BHDR(bh)->h_hash);
+ struct mb_cache_entry *ce;
+ int error;
+
+ ce = mb_cache_entry_alloc(ext4_xattr_cache);
+ if (!ce) {
+ ea_bdebug(bh, "out of memory");
+ return;
+ }
+ error = mb_cache_entry_insert(ce, bh->b_bdev, bh->b_blocknr, &hash);
+ if (error) {
+ mb_cache_entry_free(ce);
+ if (error == -EBUSY) {
+ ea_bdebug(bh, "already in cache");
+ error = 0;
+ }
+ } else {
+ ea_bdebug(bh, "inserting [%x]", (int)hash);
+ mb_cache_entry_release(ce);
+ }
+}
+
+/*
+ * ext4_xattr_cmp()
+ *
+ * Compare two extended attribute blocks for equality.
+ *
+ * Returns 0 if the blocks are equal, 1 if they differ, and
+ * a negative error number on errors.
+ */
+static int
+ext4_xattr_cmp(struct ext4_xattr_header *header1,
+ struct ext4_xattr_header *header2)
+{
+ struct ext4_xattr_entry *entry1, *entry2;
+
+ entry1 = ENTRY(header1+1);
+ entry2 = ENTRY(header2+1);
+ while (!IS_LAST_ENTRY(entry1)) {
+ if (IS_LAST_ENTRY(entry2))
+ return 1;
+ if (entry1->e_hash != entry2->e_hash ||
+ entry1->e_name_index != entry2->e_name_index ||
+ entry1->e_name_len != entry2->e_name_len ||
+ entry1->e_value_size != entry2->e_value_size ||
+ memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len))
+ return 1;
+ if (entry1->e_value_block != 0 || entry2->e_value_block != 0)
+ return -EIO;
+ if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs),
+ (char *)header2 + le16_to_cpu(entry2->e_value_offs),
+ le32_to_cpu(entry1->e_value_size)))
+ return 1;
+
+ entry1 = EXT4_XATTR_NEXT(entry1);
+ entry2 = EXT4_XATTR_NEXT(entry2);
+ }
+ if (!IS_LAST_ENTRY(entry2))
+ return 1;
+ return 0;
+}
+
+/*
+ * ext4_xattr_cache_find()
+ *
+ * Find an identical extended attribute block.
+ *
+ * Returns a pointer to the block found, or NULL if such a block was
+ * not found or an error occurred.
+ */
+static struct buffer_head *
+ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header,
+ struct mb_cache_entry **pce)
+{
+ __u32 hash = le32_to_cpu(header->h_hash);
+ struct mb_cache_entry *ce;
+
+ if (!header->h_hash)
+ return NULL; /* never share */
+ ea_idebug(inode, "looking for cached blocks [%x]", (int)hash);
+again:
+ ce = mb_cache_entry_find_first(ext4_xattr_cache, 0,
+ inode->i_sb->s_bdev, hash);
+ while (ce) {
+ struct buffer_head *bh;
+
+ if (IS_ERR(ce)) {
+ if (PTR_ERR(ce) == -EAGAIN)
+ goto again;
+ break;
+ }
+ bh = sb_bread(inode->i_sb, ce->e_block);
+ if (!bh) {
+ ext4_error(inode->i_sb, __FUNCTION__,
+ "inode %lu: block %lu read error",
+ inode->i_ino, (unsigned long) ce->e_block);
+ } else if (le32_to_cpu(BHDR(bh)->h_refcount) >=
+ EXT4_XATTR_REFCOUNT_MAX) {
+ ea_idebug(inode, "block %lu refcount %d>=%d",
+ (unsigned long) ce->e_block,
+ le32_to_cpu(BHDR(bh)->h_refcount),
+ EXT4_XATTR_REFCOUNT_MAX);
+ } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) {
+ *pce = ce;
+ return bh;
+ }
+ brelse(bh);
+ ce = mb_cache_entry_find_next(ce, 0, inode->i_sb->s_bdev, hash);
+ }
+ return NULL;
+}
+
+#define NAME_HASH_SHIFT 5
+#define VALUE_HASH_SHIFT 16
+
+/*
+ * ext4_xattr_hash_entry()
+ *
+ * Compute the hash of an extended attribute.
+ */
+static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header,
+ struct ext4_xattr_entry *entry)
+{
+ __u32 hash = 0;
+ char *name = entry->e_name;
+ int n;
+
+ for (n=0; n < entry->e_name_len; n++) {
+ hash = (hash << NAME_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
+ *name++;
+ }
+
+ if (entry->e_value_block == 0 && entry->e_value_size != 0) {
+ __le32 *value = (__le32 *)((char *)header +
+ le16_to_cpu(entry->e_value_offs));
+ for (n = (le32_to_cpu(entry->e_value_size) +
+ EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) {
+ hash = (hash << VALUE_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
+ le32_to_cpu(*value++);
+ }
+ }
+ entry->e_hash = cpu_to_le32(hash);
+}
+
+#undef NAME_HASH_SHIFT
+#undef VALUE_HASH_SHIFT
+
+#define BLOCK_HASH_SHIFT 16
+
+/*
+ * ext4_xattr_rehash()
+ *
+ * Re-compute the extended attribute hash value after an entry has changed.
+ */
+static void ext4_xattr_rehash(struct ext4_xattr_header *header,
+ struct ext4_xattr_entry *entry)
+{
+ struct ext4_xattr_entry *here;
+ __u32 hash = 0;
+
+ ext4_xattr_hash_entry(header, entry);
+ here = ENTRY(header+1);
+ while (!IS_LAST_ENTRY(here)) {
+ if (!here->e_hash) {
+ /* Block is not shared if an entry's hash value == 0 */
+ hash = 0;
+ break;
+ }
+ hash = (hash << BLOCK_HASH_SHIFT) ^
+ (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
+ le32_to_cpu(here->e_hash);
+ here = EXT4_XATTR_NEXT(here);
+ }
+ header->h_hash = cpu_to_le32(hash);
+}
+
+#undef BLOCK_HASH_SHIFT
+
+int __init
+init_ext4_xattr(void)
+{
+ ext4_xattr_cache = mb_cache_create("ext4_xattr", NULL,
+ sizeof(struct mb_cache_entry) +
+ sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]), 1, 6);
+ if (!ext4_xattr_cache)
+ return -ENOMEM;
+ return 0;
+}
+
+void
+exit_ext4_xattr(void)
+{
+ if (ext4_xattr_cache)
+ mb_cache_destroy(ext4_xattr_cache);
+ ext4_xattr_cache = NULL;
+}
diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h
new file mode 100644
index 000000000000..79432b35398f
--- /dev/null
+++ b/fs/ext4/xattr.h
@@ -0,0 +1,145 @@
+/*
+ File: fs/ext4/xattr.h
+
+ On-disk format of extended attributes for the ext4 filesystem.
+
+ (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
+*/
+
+#include <linux/xattr.h>
+
+/* Magic value in attribute blocks */
+#define EXT4_XATTR_MAGIC 0xEA020000
+
+/* Maximum number of references to one attribute block */
+#define EXT4_XATTR_REFCOUNT_MAX 1024
+
+/* Name indexes */
+#define EXT4_XATTR_INDEX_USER 1
+#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2
+#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3
+#define EXT4_XATTR_INDEX_TRUSTED 4
+#define EXT4_XATTR_INDEX_LUSTRE 5
+#define EXT4_XATTR_INDEX_SECURITY 6
+
+struct ext4_xattr_header {
+ __le32 h_magic; /* magic number for identification */
+ __le32 h_refcount; /* reference count */
+ __le32 h_blocks; /* number of disk blocks used */
+ __le32 h_hash; /* hash value of all attributes */
+ __u32 h_reserved[4]; /* zero right now */
+};
+
+struct ext4_xattr_ibody_header {
+ __le32 h_magic; /* magic number for identification */
+};
+
+struct ext4_xattr_entry {
+ __u8 e_name_len; /* length of name */
+ __u8 e_name_index; /* attribute name index */
+ __le16 e_value_offs; /* offset in disk block of value */
+ __le32 e_value_block; /* disk block attribute is stored on (n/i) */
+ __le32 e_value_size; /* size of attribute value */
+ __le32 e_hash; /* hash value of name and value */
+ char e_name[0]; /* attribute name */
+};
+
+#define EXT4_XATTR_PAD_BITS 2
+#define EXT4_XATTR_PAD (1<<EXT4_XATTR_PAD_BITS)
+#define EXT4_XATTR_ROUND (EXT4_XATTR_PAD-1)
+#define EXT4_XATTR_LEN(name_len) \
+ (((name_len) + EXT4_XATTR_ROUND + \
+ sizeof(struct ext4_xattr_entry)) & ~EXT4_XATTR_ROUND)
+#define EXT4_XATTR_NEXT(entry) \
+ ( (struct ext4_xattr_entry *)( \
+ (char *)(entry) + EXT4_XATTR_LEN((entry)->e_name_len)) )
+#define EXT4_XATTR_SIZE(size) \
+ (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND)
+
+# ifdef CONFIG_EXT4DEV_FS_XATTR
+
+extern struct xattr_handler ext4_xattr_user_handler;
+extern struct xattr_handler ext4_xattr_trusted_handler;
+extern struct xattr_handler ext4_xattr_acl_access_handler;
+extern struct xattr_handler ext4_xattr_acl_default_handler;
+extern struct xattr_handler ext4_xattr_security_handler;
+
+extern ssize_t ext4_listxattr(struct dentry *, char *, size_t);
+
+extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t);
+extern int ext4_xattr_list(struct inode *, char *, size_t);
+extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int);
+extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int);
+
+extern void ext4_xattr_delete_inode(handle_t *, struct inode *);
+extern void ext4_xattr_put_super(struct super_block *);
+
+extern int init_ext4_xattr(void);
+extern void exit_ext4_xattr(void);
+
+extern struct xattr_handler *ext4_xattr_handlers[];
+
+# else /* CONFIG_EXT4DEV_FS_XATTR */
+
+static inline int
+ext4_xattr_get(struct inode *inode, int name_index, const char *name,
+ void *buffer, size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int
+ext4_xattr_list(struct inode *inode, void *buffer, size_t size)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int
+ext4_xattr_set(struct inode *inode, int name_index, const char *name,
+ const void *value, size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int
+ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index,
+ const char *name, const void *value, size_t size, int flags)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline void
+ext4_xattr_delete_inode(handle_t *handle, struct inode *inode)
+{
+}
+
+static inline void
+ext4_xattr_put_super(struct super_block *sb)
+{
+}
+
+static inline int
+init_ext4_xattr(void)
+{
+ return 0;
+}
+
+static inline void
+exit_ext4_xattr(void)
+{
+}
+
+#define ext4_xattr_handlers NULL
+
+# endif /* CONFIG_EXT4DEV_FS_XATTR */
+
+#ifdef CONFIG_EXT4DEV_FS_SECURITY
+extern int ext4_init_security(handle_t *handle, struct inode *inode,
+ struct inode *dir);
+#else
+static inline int ext4_init_security(handle_t *handle, struct inode *inode,
+ struct inode *dir)
+{
+ return 0;
+}
+#endif
diff --git a/fs/ext4/xattr_security.c b/fs/ext4/xattr_security.c
new file mode 100644
index 000000000000..b6a6861951f9
--- /dev/null
+++ b/fs/ext4/xattr_security.c
@@ -0,0 +1,77 @@
+/*
+ * linux/fs/ext4/xattr_security.c
+ * Handler for storing security labels as extended attributes.
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/ext4_fs.h>
+#include <linux/security.h>
+#include "xattr.h"
+
+static size_t
+ext4_xattr_security_list(struct inode *inode, char *list, size_t list_size,
+ const char *name, size_t name_len)
+{
+ const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
+ const size_t total_len = prefix_len + name_len + 1;
+
+
+ if (list && total_len <= list_size) {
+ memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
+ memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
+ }
+ return total_len;
+}
+
+static int
+ext4_xattr_security_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return ext4_xattr_get(inode, EXT4_XATTR_INDEX_SECURITY, name,
+ buffer, size);
+}
+
+static int
+ext4_xattr_security_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return ext4_xattr_set(inode, EXT4_XATTR_INDEX_SECURITY, name,
+ value, size, flags);
+}
+
+int
+ext4_init_security(handle_t *handle, struct inode *inode, struct inode *dir)
+{
+ int err;
+ size_t len;
+ void *value;
+ char *name;
+
+ err = security_inode_init_security(inode, dir, &name, &value, &len);
+ if (err) {
+ if (err == -EOPNOTSUPP)
+ return 0;
+ return err;
+ }
+ err = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_SECURITY,
+ name, value, len, 0);
+ kfree(name);
+ kfree(value);
+ return err;
+}
+
+struct xattr_handler ext4_xattr_security_handler = {
+ .prefix = XATTR_SECURITY_PREFIX,
+ .list = ext4_xattr_security_list,
+ .get = ext4_xattr_security_get,
+ .set = ext4_xattr_security_set,
+};
diff --git a/fs/ext4/xattr_trusted.c b/fs/ext4/xattr_trusted.c
new file mode 100644
index 000000000000..b76f2dbc82da
--- /dev/null
+++ b/fs/ext4/xattr_trusted.c
@@ -0,0 +1,62 @@
+/*
+ * linux/fs/ext4/xattr_trusted.c
+ * Handler for trusted extended attributes.
+ *
+ * Copyright (C) 2003 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/capability.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/ext4_fs.h>
+#include "xattr.h"
+
+#define XATTR_TRUSTED_PREFIX "trusted."
+
+static size_t
+ext4_xattr_trusted_list(struct inode *inode, char *list, size_t list_size,
+ const char *name, size_t name_len)
+{
+ const size_t prefix_len = sizeof(XATTR_TRUSTED_PREFIX)-1;
+ const size_t total_len = prefix_len + name_len + 1;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return 0;
+
+ if (list && total_len <= list_size) {
+ memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
+ memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
+ }
+ return total_len;
+}
+
+static int
+ext4_xattr_trusted_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return ext4_xattr_get(inode, EXT4_XATTR_INDEX_TRUSTED, name,
+ buffer, size);
+}
+
+static int
+ext4_xattr_trusted_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ return ext4_xattr_set(inode, EXT4_XATTR_INDEX_TRUSTED, name,
+ value, size, flags);
+}
+
+struct xattr_handler ext4_xattr_trusted_handler = {
+ .prefix = XATTR_TRUSTED_PREFIX,
+ .list = ext4_xattr_trusted_list,
+ .get = ext4_xattr_trusted_get,
+ .set = ext4_xattr_trusted_set,
+};
diff --git a/fs/ext4/xattr_user.c b/fs/ext4/xattr_user.c
new file mode 100644
index 000000000000..c53cded0761a
--- /dev/null
+++ b/fs/ext4/xattr_user.c
@@ -0,0 +1,64 @@
+/*
+ * linux/fs/ext4/xattr_user.c
+ * Handler for extended user attributes.
+ *
+ * Copyright (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/ext4_jbd2.h>
+#include <linux/ext4_fs.h>
+#include "xattr.h"
+
+#define XATTR_USER_PREFIX "user."
+
+static size_t
+ext4_xattr_user_list(struct inode *inode, char *list, size_t list_size,
+ const char *name, size_t name_len)
+{
+ const size_t prefix_len = sizeof(XATTR_USER_PREFIX)-1;
+ const size_t total_len = prefix_len + name_len + 1;
+
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return 0;
+
+ if (list && total_len <= list_size) {
+ memcpy(list, XATTR_USER_PREFIX, prefix_len);
+ memcpy(list+prefix_len, name, name_len);
+ list[prefix_len + name_len] = '\0';
+ }
+ return total_len;
+}
+
+static int
+ext4_xattr_user_get(struct inode *inode, const char *name,
+ void *buffer, size_t size)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
+ return ext4_xattr_get(inode, EXT4_XATTR_INDEX_USER, name, buffer, size);
+}
+
+static int
+ext4_xattr_user_set(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
+{
+ if (strcmp(name, "") == 0)
+ return -EINVAL;
+ if (!test_opt(inode->i_sb, XATTR_USER))
+ return -EOPNOTSUPP;
+ return ext4_xattr_set(inode, EXT4_XATTR_INDEX_USER, name,
+ value, size, flags);
+}
+
+struct xattr_handler ext4_xattr_user_handler = {
+ .prefix = XATTR_USER_PREFIX,
+ .list = ext4_xattr_user_list,
+ .get = ext4_xattr_user_get,
+ .set = ext4_xattr_user_set,
+};
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