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-rw-r--r--fs/pipe.c10
-rw-r--r--fs/splice.c148
-rw-r--r--include/linux/fs.h2
-rw-r--r--include/linux/pipe_fs_i.h1
-rw-r--r--include/linux/sched.h6
-rw-r--r--kernel/exit.c4
6 files changed, 150 insertions, 21 deletions
diff --git a/fs/pipe.c b/fs/pipe.c
index 705b48692627..036536f072c9 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -691,12 +691,10 @@ struct pipe_inode_info * alloc_pipe_info(struct inode *inode)
return info;
}
-void free_pipe_info(struct inode *inode)
+void __free_pipe_info(struct pipe_inode_info *info)
{
int i;
- struct pipe_inode_info *info = inode->i_pipe;
- inode->i_pipe = NULL;
for (i = 0; i < PIPE_BUFFERS; i++) {
struct pipe_buffer *buf = info->bufs + i;
if (buf->ops)
@@ -707,6 +705,12 @@ void free_pipe_info(struct inode *inode)
kfree(info);
}
+void free_pipe_info(struct inode *inode)
+{
+ __free_pipe_info(inode->i_pipe);
+ inode->i_pipe = NULL;
+}
+
static struct vfsmount *pipe_mnt __read_mostly;
static int pipefs_delete_dentry(struct dentry *dentry)
{
diff --git a/fs/splice.c b/fs/splice.c
index a5326127aad5..c47b561edac0 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -680,8 +680,7 @@ EXPORT_SYMBOL(generic_splice_sendpage);
* Attempt to initiate a splice from pipe to file.
*/
static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
- loff_t __user *off_out, size_t len,
- unsigned int flags)
+ size_t len, unsigned int flags)
{
loff_t pos;
int ret;
@@ -692,9 +691,6 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
if (!(out->f_mode & FMODE_WRITE))
return -EBADF;
- if (off_out && copy_from_user(&out->f_pos, off_out, sizeof(loff_t)))
- return -EFAULT;
-
pos = out->f_pos;
ret = rw_verify_area(WRITE, out, &pos, len);
@@ -707,9 +703,8 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
/*
* Attempt to initiate a splice from a file to a pipe.
*/
-static long do_splice_to(struct file *in, loff_t __user *off_in,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
+static long do_splice_to(struct file *in, struct pipe_inode_info *pipe,
+ size_t len, unsigned int flags)
{
loff_t pos, isize, left;
int ret;
@@ -720,9 +715,6 @@ static long do_splice_to(struct file *in, loff_t __user *off_in,
if (!(in->f_mode & FMODE_READ))
return -EBADF;
- if (off_in && copy_from_user(&in->f_pos, off_in, sizeof(loff_t)))
- return -EFAULT;
-
pos = in->f_pos;
ret = rw_verify_area(READ, in, &pos, len);
@@ -740,6 +732,118 @@ static long do_splice_to(struct file *in, loff_t __user *off_in,
return in->f_op->splice_read(in, pipe, len, flags);
}
+long do_splice_direct(struct file *in, struct file *out, size_t len,
+ unsigned int flags)
+{
+ struct pipe_inode_info *pipe;
+ long ret, bytes;
+ umode_t i_mode;
+ int i;
+
+ /*
+ * We require the input being a regular file, as we don't want to
+ * randomly drop data for eg socket -> socket splicing. Use the
+ * piped splicing for that!
+ */
+ i_mode = in->f_dentry->d_inode->i_mode;
+ if (unlikely(!S_ISREG(i_mode) && !S_ISBLK(i_mode)))
+ return -EINVAL;
+
+ /*
+ * neither in nor out is a pipe, setup an internal pipe attached to
+ * 'out' and transfer the wanted data from 'in' to 'out' through that
+ */
+ pipe = current->splice_pipe;
+ if (!pipe) {
+ pipe = alloc_pipe_info(NULL);
+ if (!pipe)
+ return -ENOMEM;
+
+ /*
+ * We don't have an immediate reader, but we'll read the stuff
+ * out of the pipe right after the move_to_pipe(). So set
+ * PIPE_READERS appropriately.
+ */
+ pipe->readers = 1;
+
+ current->splice_pipe = pipe;
+ }
+
+ /*
+ * do the splice
+ */
+ ret = 0;
+ bytes = 0;
+
+ while (len) {
+ size_t read_len, max_read_len;
+
+ /*
+ * Do at most PIPE_BUFFERS pages worth of transfer:
+ */
+ max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
+
+ ret = do_splice_to(in, pipe, max_read_len, flags);
+ if (unlikely(ret < 0))
+ goto out_release;
+
+ read_len = ret;
+
+ /*
+ * NOTE: nonblocking mode only applies to the input. We
+ * must not do the output in nonblocking mode as then we
+ * could get stuck data in the internal pipe:
+ */
+ ret = do_splice_from(pipe, out, read_len,
+ flags & ~SPLICE_F_NONBLOCK);
+ if (unlikely(ret < 0))
+ goto out_release;
+
+ bytes += ret;
+ len -= ret;
+
+ /*
+ * In nonblocking mode, if we got back a short read then
+ * that was due to either an IO error or due to the
+ * pagecache entry not being there. In the IO error case
+ * the _next_ splice attempt will produce a clean IO error
+ * return value (not a short read), so in both cases it's
+ * correct to break out of the loop here:
+ */
+ if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len))
+ break;
+ }
+
+ pipe->nrbufs = pipe->curbuf = 0;
+
+ return bytes;
+
+out_release:
+ /*
+ * If we did an incomplete transfer we must release
+ * the pipe buffers in question:
+ */
+ for (i = 0; i < PIPE_BUFFERS; i++) {
+ struct pipe_buffer *buf = pipe->bufs + i;
+
+ if (buf->ops) {
+ buf->ops->release(pipe, buf);
+ buf->ops = NULL;
+ }
+ }
+ pipe->nrbufs = pipe->curbuf = 0;
+
+ /*
+ * If we transferred some data, return the number of bytes:
+ */
+ if (bytes > 0)
+ return bytes;
+
+ return ret;
+}
+
+EXPORT_SYMBOL(do_splice_direct);
+
/*
* Determine where to splice to/from.
*/
@@ -749,25 +853,33 @@ static long do_splice(struct file *in, loff_t __user *off_in,
{
struct pipe_inode_info *pipe;
- if (off_out && out->f_op->llseek == no_llseek)
- return -EINVAL;
- if (off_in && in->f_op->llseek == no_llseek)
- return -EINVAL;
-
pipe = in->f_dentry->d_inode->i_pipe;
if (pipe) {
if (off_in)
return -ESPIPE;
+ if (off_out) {
+ if (out->f_op->llseek == no_llseek)
+ return -EINVAL;
+ if (copy_from_user(&out->f_pos, off_out,
+ sizeof(loff_t)))
+ return -EFAULT;
+ }
- return do_splice_from(pipe, out, off_out, len, flags);
+ return do_splice_from(pipe, out, len, flags);
}
pipe = out->f_dentry->d_inode->i_pipe;
if (pipe) {
if (off_out)
return -ESPIPE;
+ if (off_in) {
+ if (in->f_op->llseek == no_llseek)
+ return -EINVAL;
+ if (copy_from_user(&in->f_pos, off_in, sizeof(loff_t)))
+ return -EFAULT;
+ }
- return do_splice_to(in, off_in, pipe, len, flags);
+ return do_splice_to(in, pipe, len, flags);
}
return -EINVAL;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7e6454454fbd..9e8e2ee353b4 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1613,6 +1613,8 @@ extern void do_generic_mapping_read(struct address_space *mapping,
loff_t *, read_descriptor_t *, read_actor_t);
extern ssize_t generic_file_splice_read(struct file *, struct pipe_inode_info *, size_t, unsigned int);
extern ssize_t generic_file_splice_write(struct pipe_inode_info *, struct file *, size_t, unsigned int);
+extern long do_splice_direct(struct file *in, struct file *out,
+ size_t len, unsigned int flags);
extern void
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
extern ssize_t generic_file_readv(struct file *filp, const struct iovec *iov,
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 9cf99cb34c15..660e9d866e5d 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -58,6 +58,7 @@ void pipe_wait(struct pipe_inode_info *pipe);
struct pipe_inode_info * alloc_pipe_info(struct inode * inode);
void free_pipe_info(struct inode * inode);
+void __free_pipe_info(struct pipe_inode_info *);
/*
* splice is tied to pipes as a transport (at least for now), so we'll just
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 541f4828f5e7..e194ec75833d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -684,6 +684,7 @@ static inline void prefetch_stack(struct task_struct *t) { }
struct audit_context; /* See audit.c */
struct mempolicy;
+struct pipe_inode_info;
enum sleep_type {
SLEEP_NORMAL,
@@ -882,6 +883,11 @@ struct task_struct {
atomic_t fs_excl; /* holding fs exclusive resources */
struct rcu_head rcu;
+
+ /*
+ * cache last used pipe for splice
+ */
+ struct pipe_inode_info *splice_pipe;
};
static inline pid_t process_group(struct task_struct *tsk)
diff --git a/kernel/exit.c b/kernel/exit.c
index 6c2eeb8f6390..1a9787ac6173 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -34,6 +34,7 @@
#include <linux/mutex.h>
#include <linux/futex.h>
#include <linux/compat.h>
+#include <linux/pipe_fs_i.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
@@ -941,6 +942,9 @@ fastcall NORET_TYPE void do_exit(long code)
if (tsk->io_context)
exit_io_context();
+ if (tsk->splice_pipe)
+ __free_pipe_info(tsk->splice_pipe);
+
/* PF_DEAD causes final put_task_struct after we schedule. */
preempt_disable();
BUG_ON(tsk->flags & PF_DEAD);
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