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Diffstat (limited to 'fs/splice.c')
-rw-r--r--fs/splice.c243
1 files changed, 155 insertions, 88 deletions
diff --git a/fs/splice.c b/fs/splice.c
index d983d375ff11..218e24b1ac40 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -201,7 +201,8 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe,
unsigned int tail = pipe->tail;
unsigned int head = pipe->head;
unsigned int mask = pipe->ring_size - 1;
- int ret = 0, page_nr = 0;
+ ssize_t ret = 0;
+ int page_nr = 0;
if (!spd_pages)
return 0;
@@ -673,10 +674,13 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
.u.file = out,
};
int nbufs = pipe->max_usage;
- struct bio_vec *array = kcalloc(nbufs, sizeof(struct bio_vec),
- GFP_KERNEL);
+ struct bio_vec *array;
ssize_t ret;
+ if (!out->f_op->write_iter)
+ return -EINVAL;
+
+ array = kcalloc(nbufs, sizeof(struct bio_vec), GFP_KERNEL);
if (unlikely(!array))
return -ENOMEM;
@@ -684,6 +688,7 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
splice_from_pipe_begin(&sd);
while (sd.total_len) {
+ struct kiocb kiocb;
struct iov_iter from;
unsigned int head, tail, mask;
size_t left;
@@ -733,7 +738,10 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
}
iov_iter_bvec(&from, ITER_SOURCE, array, n, sd.total_len - left);
- ret = vfs_iter_write(out, &from, &sd.pos, 0);
+ init_sync_kiocb(&kiocb, out);
+ kiocb.ki_pos = sd.pos;
+ ret = call_write_iter(out, &kiocb, &from);
+ sd.pos = kiocb.ki_pos;
if (ret <= 0)
break;
@@ -925,8 +933,8 @@ static int warn_unsupported(struct file *file, const char *op)
/*
* Attempt to initiate a splice from pipe to file.
*/
-static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
- loff_t *ppos, size_t len, unsigned int flags)
+static ssize_t do_splice_from(struct pipe_inode_info *pipe, struct file *out,
+ loff_t *ppos, size_t len, unsigned int flags)
{
if (unlikely(!out->f_op->splice_write))
return warn_unsupported(out, "write");
@@ -944,27 +952,15 @@ static void do_splice_eof(struct splice_desc *sd)
sd->splice_eof(sd);
}
-/**
- * vfs_splice_read - Read data from a file and splice it into a pipe
- * @in: File to splice from
- * @ppos: Input file offset
- * @pipe: Pipe to splice to
- * @len: Number of bytes to splice
- * @flags: Splice modifier flags (SPLICE_F_*)
- *
- * Splice the requested amount of data from the input file to the pipe. This
- * is synchronous as the caller must hold the pipe lock across the entire
- * operation.
- *
- * If successful, it returns the amount of data spliced, 0 if it hit the EOF or
- * a hole and a negative error code otherwise.
+/*
+ * Callers already called rw_verify_area() on the entire range.
+ * No need to call it for sub ranges.
*/
-long vfs_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
+static ssize_t do_splice_read(struct file *in, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len,
+ unsigned int flags)
{
unsigned int p_space;
- int ret;
if (unlikely(!(in->f_mode & FMODE_READ)))
return -EBADF;
@@ -975,10 +971,6 @@ long vfs_splice_read(struct file *in, loff_t *ppos,
p_space = pipe->max_usage - pipe_occupancy(pipe->head, pipe->tail);
len = min_t(size_t, len, p_space << PAGE_SHIFT);
- ret = rw_verify_area(READ, in, ppos, len);
- if (unlikely(ret < 0))
- return ret;
-
if (unlikely(len > MAX_RW_COUNT))
len = MAX_RW_COUNT;
@@ -992,6 +984,34 @@ long vfs_splice_read(struct file *in, loff_t *ppos,
return copy_splice_read(in, ppos, pipe, len, flags);
return in->f_op->splice_read(in, ppos, pipe, len, flags);
}
+
+/**
+ * vfs_splice_read - Read data from a file and splice it into a pipe
+ * @in: File to splice from
+ * @ppos: Input file offset
+ * @pipe: Pipe to splice to
+ * @len: Number of bytes to splice
+ * @flags: Splice modifier flags (SPLICE_F_*)
+ *
+ * Splice the requested amount of data from the input file to the pipe. This
+ * is synchronous as the caller must hold the pipe lock across the entire
+ * operation.
+ *
+ * If successful, it returns the amount of data spliced, 0 if it hit the EOF or
+ * a hole and a negative error code otherwise.
+ */
+ssize_t vfs_splice_read(struct file *in, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len,
+ unsigned int flags)
+{
+ ssize_t ret;
+
+ ret = rw_verify_area(READ, in, ppos, len);
+ if (unlikely(ret < 0))
+ return ret;
+
+ return do_splice_read(in, ppos, pipe, len, flags);
+}
EXPORT_SYMBOL_GPL(vfs_splice_read);
/**
@@ -1011,7 +1031,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
splice_direct_actor *actor)
{
struct pipe_inode_info *pipe;
- long ret, bytes;
+ ssize_t ret, bytes;
size_t len;
int i, flags, more;
@@ -1066,7 +1086,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
size_t read_len;
loff_t pos = sd->pos, prev_pos = pos;
- ret = vfs_splice_read(in, &pos, pipe, len, flags);
+ ret = do_splice_read(in, &pos, pipe, len, flags);
if (unlikely(ret <= 0))
goto read_failure;
@@ -1138,9 +1158,20 @@ static int direct_splice_actor(struct pipe_inode_info *pipe,
struct splice_desc *sd)
{
struct file *file = sd->u.file;
+ long ret;
+
+ file_start_write(file);
+ ret = do_splice_from(pipe, file, sd->opos, sd->total_len, sd->flags);
+ file_end_write(file);
+ return ret;
+}
+
+static int splice_file_range_actor(struct pipe_inode_info *pipe,
+ struct splice_desc *sd)
+{
+ struct file *file = sd->u.file;
- return do_splice_from(pipe, file, sd->opos, sd->total_len,
- sd->flags);
+ return do_splice_from(pipe, file, sd->opos, sd->total_len, sd->flags);
}
static void direct_file_splice_eof(struct splice_desc *sd)
@@ -1151,24 +1182,10 @@ static void direct_file_splice_eof(struct splice_desc *sd)
file->f_op->splice_eof(file);
}
-/**
- * do_splice_direct - splices data directly between two files
- * @in: file to splice from
- * @ppos: input file offset
- * @out: file to splice to
- * @opos: output file offset
- * @len: number of bytes to splice
- * @flags: splice modifier flags
- *
- * Description:
- * For use by do_sendfile(). splice can easily emulate sendfile, but
- * doing it in the application would incur an extra system call
- * (splice in + splice out, as compared to just sendfile()). So this helper
- * can splice directly through a process-private pipe.
- *
- */
-long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
- loff_t *opos, size_t len, unsigned int flags)
+static ssize_t do_splice_direct_actor(struct file *in, loff_t *ppos,
+ struct file *out, loff_t *opos,
+ size_t len, unsigned int flags,
+ splice_direct_actor *actor)
{
struct splice_desc sd = {
.len = len,
@@ -1179,7 +1196,7 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
.splice_eof = direct_file_splice_eof,
.opos = opos,
};
- long ret;
+ ssize_t ret;
if (unlikely(!(out->f_mode & FMODE_WRITE)))
return -EBADF;
@@ -1187,18 +1204,63 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
if (unlikely(out->f_flags & O_APPEND))
return -EINVAL;
- ret = rw_verify_area(WRITE, out, opos, len);
- if (unlikely(ret < 0))
- return ret;
-
- ret = splice_direct_to_actor(in, &sd, direct_splice_actor);
+ ret = splice_direct_to_actor(in, &sd, actor);
if (ret > 0)
*ppos = sd.pos;
return ret;
}
+/**
+ * do_splice_direct - splices data directly between two files
+ * @in: file to splice from
+ * @ppos: input file offset
+ * @out: file to splice to
+ * @opos: output file offset
+ * @len: number of bytes to splice
+ * @flags: splice modifier flags
+ *
+ * Description:
+ * For use by do_sendfile(). splice can easily emulate sendfile, but
+ * doing it in the application would incur an extra system call
+ * (splice in + splice out, as compared to just sendfile()). So this helper
+ * can splice directly through a process-private pipe.
+ *
+ * Callers already called rw_verify_area() on the entire range.
+ */
+ssize_t do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len, unsigned int flags)
+{
+ return do_splice_direct_actor(in, ppos, out, opos, len, flags,
+ direct_splice_actor);
+}
EXPORT_SYMBOL(do_splice_direct);
+/**
+ * splice_file_range - splices data between two files for copy_file_range()
+ * @in: file to splice from
+ * @ppos: input file offset
+ * @out: file to splice to
+ * @opos: output file offset
+ * @len: number of bytes to splice
+ *
+ * Description:
+ * For use by ->copy_file_range() methods.
+ * Like do_splice_direct(), but vfs_copy_file_range() already holds
+ * start_file_write() on @out file.
+ *
+ * Callers already called rw_verify_area() on the entire range.
+ */
+ssize_t splice_file_range(struct file *in, loff_t *ppos, struct file *out,
+ loff_t *opos, size_t len)
+{
+ lockdep_assert(file_write_started(out));
+
+ return do_splice_direct_actor(in, ppos, out, opos,
+ min_t(size_t, len, MAX_RW_COUNT),
+ 0, splice_file_range_actor);
+}
+EXPORT_SYMBOL(splice_file_range);
+
static int wait_for_space(struct pipe_inode_info *pipe, unsigned flags)
{
for (;;) {
@@ -1220,17 +1282,17 @@ static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe,
struct pipe_inode_info *opipe,
size_t len, unsigned int flags);
-long splice_file_to_pipe(struct file *in,
- struct pipe_inode_info *opipe,
- loff_t *offset,
- size_t len, unsigned int flags)
+ssize_t splice_file_to_pipe(struct file *in,
+ struct pipe_inode_info *opipe,
+ loff_t *offset,
+ size_t len, unsigned int flags)
{
- long ret;
+ ssize_t ret;
pipe_lock(opipe);
ret = wait_for_space(opipe, flags);
if (!ret)
- ret = vfs_splice_read(in, offset, opipe, len, flags);
+ ret = do_splice_read(in, offset, opipe, len, flags);
pipe_unlock(opipe);
if (ret > 0)
wakeup_pipe_readers(opipe);
@@ -1240,13 +1302,13 @@ long splice_file_to_pipe(struct file *in,
/*
* Determine where to splice to/from.
*/
-long do_splice(struct file *in, loff_t *off_in, struct file *out,
- loff_t *off_out, size_t len, unsigned int flags)
+ssize_t do_splice(struct file *in, loff_t *off_in, struct file *out,
+ loff_t *off_out, size_t len, unsigned int flags)
{
struct pipe_inode_info *ipipe;
struct pipe_inode_info *opipe;
loff_t offset;
- long ret;
+ ssize_t ret;
if (unlikely(!(in->f_mode & FMODE_READ) ||
!(out->f_mode & FMODE_WRITE)))
@@ -1307,6 +1369,10 @@ long do_splice(struct file *in, loff_t *off_in, struct file *out,
offset = in->f_pos;
}
+ ret = rw_verify_area(READ, in, &offset, len);
+ if (unlikely(ret < 0))
+ return ret;
+
if (out->f_flags & O_NONBLOCK)
flags |= SPLICE_F_NONBLOCK;
@@ -1333,14 +1399,14 @@ long do_splice(struct file *in, loff_t *off_in, struct file *out,
return ret;
}
-static long __do_splice(struct file *in, loff_t __user *off_in,
- struct file *out, loff_t __user *off_out,
- size_t len, unsigned int flags)
+static ssize_t __do_splice(struct file *in, loff_t __user *off_in,
+ struct file *out, loff_t __user *off_out,
+ size_t len, unsigned int flags)
{
struct pipe_inode_info *ipipe;
struct pipe_inode_info *opipe;
loff_t offset, *__off_in = NULL, *__off_out = NULL;
- long ret;
+ ssize_t ret;
ipipe = get_pipe_info(in, true);
opipe = get_pipe_info(out, true);
@@ -1379,16 +1445,16 @@ static long __do_splice(struct file *in, loff_t __user *off_in,
return ret;
}
-static int iter_to_pipe(struct iov_iter *from,
- struct pipe_inode_info *pipe,
- unsigned flags)
+static ssize_t iter_to_pipe(struct iov_iter *from,
+ struct pipe_inode_info *pipe,
+ unsigned int flags)
{
struct pipe_buffer buf = {
.ops = &user_page_pipe_buf_ops,
.flags = flags
};
size_t total = 0;
- int ret = 0;
+ ssize_t ret = 0;
while (iov_iter_count(from)) {
struct page *pages[16];
@@ -1437,8 +1503,8 @@ static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
* For lack of a better implementation, implement vmsplice() to userspace
* as a simple copy of the pipes pages to the user iov.
*/
-static long vmsplice_to_user(struct file *file, struct iov_iter *iter,
- unsigned int flags)
+static ssize_t vmsplice_to_user(struct file *file, struct iov_iter *iter,
+ unsigned int flags)
{
struct pipe_inode_info *pipe = get_pipe_info(file, true);
struct splice_desc sd = {
@@ -1446,7 +1512,7 @@ static long vmsplice_to_user(struct file *file, struct iov_iter *iter,
.flags = flags,
.u.data = iter
};
- long ret = 0;
+ ssize_t ret = 0;
if (!pipe)
return -EBADF;
@@ -1470,11 +1536,11 @@ static long vmsplice_to_user(struct file *file, struct iov_iter *iter,
* as splice-from-memory, where the regular splice is splice-from-file (or
* to file). In both cases the output is a pipe, naturally.
*/
-static long vmsplice_to_pipe(struct file *file, struct iov_iter *iter,
- unsigned int flags)
+static ssize_t vmsplice_to_pipe(struct file *file, struct iov_iter *iter,
+ unsigned int flags)
{
struct pipe_inode_info *pipe;
- long ret = 0;
+ ssize_t ret = 0;
unsigned buf_flag = 0;
if (flags & SPLICE_F_GIFT)
@@ -1570,7 +1636,7 @@ SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in,
size_t, len, unsigned int, flags)
{
struct fd in, out;
- long error;
+ ssize_t error;
if (unlikely(!len))
return 0;
@@ -1584,7 +1650,7 @@ SYSCALL_DEFINE6(splice, int, fd_in, loff_t __user *, off_in,
out = fdget(fd_out);
if (out.file) {
error = __do_splice(in.file, off_in, out.file, off_out,
- len, flags);
+ len, flags);
fdput(out);
}
fdput(in);
@@ -1807,15 +1873,15 @@ retry:
/*
* Link contents of ipipe to opipe.
*/
-static int link_pipe(struct pipe_inode_info *ipipe,
- struct pipe_inode_info *opipe,
- size_t len, unsigned int flags)
+static ssize_t link_pipe(struct pipe_inode_info *ipipe,
+ struct pipe_inode_info *opipe,
+ size_t len, unsigned int flags)
{
struct pipe_buffer *ibuf, *obuf;
unsigned int i_head, o_head;
unsigned int i_tail, o_tail;
unsigned int i_mask, o_mask;
- int ret = 0;
+ ssize_t ret = 0;
/*
* Potential ABBA deadlock, work around it by ordering lock
@@ -1898,11 +1964,12 @@ static int link_pipe(struct pipe_inode_info *ipipe,
* The 'flags' used are the SPLICE_F_* variants, currently the only
* applicable one is SPLICE_F_NONBLOCK.
*/
-long do_tee(struct file *in, struct file *out, size_t len, unsigned int flags)
+ssize_t do_tee(struct file *in, struct file *out, size_t len,
+ unsigned int flags)
{
struct pipe_inode_info *ipipe = get_pipe_info(in, true);
struct pipe_inode_info *opipe = get_pipe_info(out, true);
- int ret = -EINVAL;
+ ssize_t ret = -EINVAL;
if (unlikely(!(in->f_mode & FMODE_READ) ||
!(out->f_mode & FMODE_WRITE)))
@@ -1939,7 +2006,7 @@ long do_tee(struct file *in, struct file *out, size_t len, unsigned int flags)
SYSCALL_DEFINE4(tee, int, fdin, int, fdout, size_t, len, unsigned int, flags)
{
struct fd in, out;
- int error;
+ ssize_t error;
if (unlikely(flags & ~SPLICE_F_ALL))
return -EINVAL;