Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs updates from Chris Mason:
 "The largest set of changes here come from Miao Xie.  He's cleaning up
  and improving read recovery/repair for raid, and has a number of
  related fixes.

  I've merged another set of fsync fixes from Filipe, and he's also
  improved the way we handle metadata write errors to make sure we force
  the FS readonly if things go wrong.

  Otherwise we have a collection of fixes and cleanups.  Dave Sterba
  gets a cookie for removing the most lines (thanks Dave)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (139 commits)
  btrfs: Fix compile error when CONFIG_SECURITY is not set.
  Btrfs: fix compiles when CONFIG_BTRFS_FS_RUN_SANITY_TESTS is off
  btrfs: Make btrfs handle security mount options internally to avoid losing security label.
  Btrfs: send, don't delay dir move if there's a new parent inode
  btrfs: add more superblock checks
  Btrfs: fix race in WAIT_SYNC ioctl
  Btrfs: be aware of btree inode write errors to avoid fs corruption
  Btrfs: remove redundant btrfs_verify_qgroup_counts declaration.
  btrfs: fix shadow warning on cmp
  Btrfs: fix compilation errors under DEBUG
  Btrfs: fix crash of btrfs_release_extent_buffer_page
  Btrfs: add missing end_page_writeback on submit_extent_page failure
  btrfs: Fix the wrong condition judgment about subset extent map
  Btrfs: fix build_backref_tree issue with multiple shared blocks
  Btrfs: cleanup error handling in build_backref_tree
  btrfs: move checks for DUMMY_ROOT into a helper
  btrfs: new define for the inline extent data start
  btrfs: kill extent_buffer_page helper
  btrfs: drop constant param from btrfs_release_extent_buffer_page
  btrfs: hide typecast to definition of BTRFS_SEND_TRANS_STUB
  ...

1 files changed, 23 insertions, 18 deletions

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 12e53556e214..b2e7bb4393f6 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -242,7 +242,7 @@ static ssize_t global_rsv_size_show(struct kobject *kobj,
 	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
 	return btrfs_show_u64(&block_rsv->size, &block_rsv->lock, buf);
 }
-BTRFS_ATTR(global_rsv_size, 0444, global_rsv_size_show);
+BTRFS_ATTR(global_rsv_size, global_rsv_size_show);
 
 static ssize_t global_rsv_reserved_show(struct kobject *kobj,
 					struct kobj_attribute *a, char *buf)
@@ -251,7 +251,7 @@ static ssize_t global_rsv_reserved_show(struct kobject *kobj,
 	struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
 	return btrfs_show_u64(&block_rsv->reserved, &block_rsv->lock, buf);
 }
-BTRFS_ATTR(global_rsv_reserved, 0444, global_rsv_reserved_show);
+BTRFS_ATTR(global_rsv_reserved, global_rsv_reserved_show);
 
 #define to_space_info(_kobj) container_of(_kobj, struct btrfs_space_info, kobj)
 #define to_raid_kobj(_kobj) container_of(_kobj, struct raid_kobject, kobj)
@@ -306,7 +306,7 @@ static ssize_t btrfs_space_info_show_##field(struct kobject *kobj,	\
 	struct btrfs_space_info *sinfo = to_space_info(kobj);		\
 	return btrfs_show_u64(&sinfo->field, &sinfo->lock, buf);	\
 }									\
-BTRFS_ATTR(field, 0444, btrfs_space_info_show_##field)
+BTRFS_ATTR(field, btrfs_space_info_show_##field)
 
 static ssize_t btrfs_space_info_show_total_bytes_pinned(struct kobject *kobj,
 						       struct kobj_attribute *a,
@@ -325,7 +325,7 @@ SPACE_INFO_ATTR(bytes_reserved);
 SPACE_INFO_ATTR(bytes_may_use);
 SPACE_INFO_ATTR(disk_used);
 SPACE_INFO_ATTR(disk_total);
-BTRFS_ATTR(total_bytes_pinned, 0444, btrfs_space_info_show_total_bytes_pinned);
+BTRFS_ATTR(total_bytes_pinned, btrfs_space_info_show_total_bytes_pinned);
 
 static struct attribute *space_info_attrs[] = {
 	BTRFS_ATTR_PTR(flags),
@@ -363,7 +363,8 @@ static ssize_t btrfs_label_show(struct kobject *kobj,
 				struct kobj_attribute *a, char *buf)
 {
 	struct btrfs_fs_info *fs_info = to_fs_info(kobj);
-	return snprintf(buf, PAGE_SIZE, "%s\n", fs_info->super_copy->label);
+	char *label = fs_info->super_copy->label;
+	return snprintf(buf, PAGE_SIZE, label[0] ? "%s\n" : "%s", label);
 }
 
 static ssize_t btrfs_label_store(struct kobject *kobj,
@@ -374,8 +375,18 @@ static ssize_t btrfs_label_store(struct kobject *kobj,
 	struct btrfs_trans_handle *trans;
 	struct btrfs_root *root = fs_info->fs_root;
 	int ret;
+	size_t p_len;
 
-	if (len >= BTRFS_LABEL_SIZE)
+	if (fs_info->sb->s_flags & MS_RDONLY)
+		return -EROFS;
+
+	/*
+	 * p_len is the len until the first occurrence of either
+	 * '\n' or '\0'
+	 */
+	p_len = strcspn(buf, "\n");
+
+	if (p_len >= BTRFS_LABEL_SIZE)
 		return -EINVAL;
 
 	trans = btrfs_start_transaction(root, 0);
@@ -383,7 +394,8 @@ static ssize_t btrfs_label_store(struct kobject *kobj,
 		return PTR_ERR(trans);
 
 	spin_lock(&root->fs_info->super_lock);
-	strcpy(fs_info->super_copy->label, buf);
+	memset(fs_info->super_copy->label, 0, BTRFS_LABEL_SIZE);
+	memcpy(fs_info->super_copy->label, buf, p_len);
 	spin_unlock(&root->fs_info->super_lock);
 	ret = btrfs_commit_transaction(trans, root);
 
@@ -392,14 +404,7 @@ static ssize_t btrfs_label_store(struct kobject *kobj,
 
 	return ret;
 }
-BTRFS_ATTR_RW(label, 0644, btrfs_label_show, btrfs_label_store);
-
-static ssize_t btrfs_no_store(struct kobject *kobj,
-				 struct kobj_attribute *a,
-				 const char *buf, size_t len)
-{
-	return -EPERM;
-}
+BTRFS_ATTR_RW(label, btrfs_label_show, btrfs_label_store);
 
 static ssize_t btrfs_nodesize_show(struct kobject *kobj,
 				struct kobj_attribute *a, char *buf)
@@ -409,7 +414,7 @@ static ssize_t btrfs_nodesize_show(struct kobject *kobj,
 	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->nodesize);
 }
 
-BTRFS_ATTR_RW(nodesize, 0444, btrfs_nodesize_show, btrfs_no_store);
+BTRFS_ATTR(nodesize, btrfs_nodesize_show);
 
 static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
 				struct kobj_attribute *a, char *buf)
@@ -419,7 +424,7 @@ static ssize_t btrfs_sectorsize_show(struct kobject *kobj,
 	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
 }
 
-BTRFS_ATTR_RW(sectorsize, 0444, btrfs_sectorsize_show, btrfs_no_store);
+BTRFS_ATTR(sectorsize, btrfs_sectorsize_show);
 
 static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
 				struct kobj_attribute *a, char *buf)
@@ -429,7 +434,7 @@ static ssize_t btrfs_clone_alignment_show(struct kobject *kobj,
 	return snprintf(buf, PAGE_SIZE, "%u\n", fs_info->super_copy->sectorsize);
 }
 
-BTRFS_ATTR_RW(clone_alignment, 0444, btrfs_clone_alignment_show, btrfs_no_store);
+BTRFS_ATTR(clone_alignment, btrfs_clone_alignment_show);
 
 static struct attribute *btrfs_attrs[] = {
 	BTRFS_ATTR_PTR(label),