#include <linux/export.h>
#include <linux/syscalls.h>
#include <linux/uio.h>
+#include <linux/fsnotify.h>
#include <linux/security.h>
#include <linux/gfp.h>
+#include <linux/net.h>
#include <linux/socket.h>
#include <linux/sched/signal.h>
#include "internal.h"
+/*
+ * Splice doesn't support FMODE_NOWAIT. Since pipes may set this flag to
+ * indicate they support non-blocking reads or writes, we must clear it
+ * here if set to avoid blocking other users of this pipe if splice is
+ * being done on it.
+ */
+static noinline void noinline pipe_clear_nowait(struct file *file)
+{
+ fmode_t fmode = READ_ONCE(file->f_mode);
+
+ do {
+ if (!(fmode & FMODE_NOWAIT))
+ break;
+ } while (!try_cmpxchg(&file->f_mode, &fmode, fmode & ~FMODE_NOWAIT));
+}
+
/*
* Attempt to steal a page from a pipe buffer. This should perhaps go into
* a vm helper function, it's already simplified quite a bit by the
*/
folio_wait_writeback(folio);
- if (folio_has_private(folio) &&
- !filemap_release_folio(folio, GFP_KERNEL))
+ if (!filemap_release_folio(folio, GFP_KERNEL))
goto out_unlock;
/*
static int page_cache_pipe_buf_confirm(struct pipe_inode_info *pipe,
struct pipe_buffer *buf)
{
- struct page *page = buf->page;
+ struct folio *folio = page_folio(buf->page);
int err;
- if (!PageUptodate(page)) {
- lock_page(page);
+ if (!folio_test_uptodate(folio)) {
+ folio_lock(folio);
/*
- * Page got truncated/unhashed. This will cause a 0-byte
+ * Folio got truncated/unhashed. This will cause a 0-byte
* splice, if this is the first page.
*/
- if (!page->mapping) {
+ if (!folio->mapping) {
err = -ENODATA;
goto error;
}
/*
* Uh oh, read-error from disk.
*/
- if (!PageUptodate(page)) {
+ if (!folio_test_uptodate(folio)) {
err = -EIO;
goto error;
}
- /*
- * Page is ok afterall, we are done.
- */
- unlock_page(page);
+ /* Folio is ok after all, we are done */
+ folio_unlock(folio);
}
return 0;
error:
- unlock_page(page);
+ folio_unlock(folio);
return err;
}
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;
}
/**
- * generic_file_splice_read - splice data from file to a pipe
- * @in: file to splice from
- * @ppos: position in @in
- * @pipe: pipe to splice to
- * @len: number of bytes to splice
- * @flags: splice modifier flags
+ * copy_splice_read - Copy data from a file and splice the copy into a pipe
+ * @in: The file to read from
+ * @ppos: Pointer to the file position to read from
+ * @pipe: The pipe to splice into
+ * @len: The amount to splice
+ * @flags: The SPLICE_F_* flags
*
- * Description:
- * Will read pages from given file and fill them into a pipe. Can be
- * used as long as it has more or less sane ->read_iter().
+ * This function allocates a bunch of pages sufficient to hold the requested
+ * amount of data (but limited by the remaining pipe capacity), passes it to
+ * the file's ->read_iter() to read into and then splices the used pages into
+ * the pipe.
*
+ * Return: On success, the number of bytes read will be returned and *@ppos
+ * will be updated if appropriate; 0 will be returned if there is no more data
+ * to be read; -EAGAIN will be returned if the pipe had no space, and some
+ * other negative error code will be returned on error. A short read may occur
+ * if the pipe has insufficient space, we reach the end of the data or we hit a
+ * hole.
*/
-ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
+ssize_t copy_splice_read(struct file *in, loff_t *ppos,
+ struct pipe_inode_info *pipe,
+ size_t len, unsigned int flags)
{
struct iov_iter to;
+ struct bio_vec *bv;
struct kiocb kiocb;
- unsigned int i_head;
- int ret;
+ struct page **pages;
+ ssize_t ret;
+ size_t used, npages, chunk, remain, keep = 0;
+ int i;
+
+ /* Work out how much data we can actually add into the pipe */
+ used = pipe_occupancy(pipe->head, pipe->tail);
+ npages = max_t(ssize_t, pipe->max_usage - used, 0);
+ len = min_t(size_t, len, npages * PAGE_SIZE);
+ npages = DIV_ROUND_UP(len, PAGE_SIZE);
+
+ bv = kzalloc(array_size(npages, sizeof(bv[0])) +
+ array_size(npages, sizeof(struct page *)), GFP_KERNEL);
+ if (!bv)
+ return -ENOMEM;
+
+ pages = (struct page **)(bv + npages);
+ npages = alloc_pages_bulk_array(GFP_USER, npages, pages);
+ if (!npages) {
+ kfree(bv);
+ return -ENOMEM;
+ }
+
+ remain = len = min_t(size_t, len, npages * PAGE_SIZE);
+
+ for (i = 0; i < npages; i++) {
+ chunk = min_t(size_t, PAGE_SIZE, remain);
+ bv[i].bv_page = pages[i];
+ bv[i].bv_offset = 0;
+ bv[i].bv_len = chunk;
+ remain -= chunk;
+ }
- iov_iter_pipe(&to, READ, pipe, len);
- i_head = to.head;
+ /* Do the I/O */
+ iov_iter_bvec(&to, ITER_DEST, bv, npages, len);
init_sync_kiocb(&kiocb, in);
kiocb.ki_pos = *ppos;
ret = call_read_iter(in, &kiocb, &to);
+
if (ret > 0) {
+ keep = DIV_ROUND_UP(ret, PAGE_SIZE);
*ppos = kiocb.ki_pos;
- file_accessed(in);
- } else if (ret < 0) {
- to.head = i_head;
- to.iov_offset = 0;
- iov_iter_advance(&to, 0); /* to free what was emitted */
- /*
- * callers of ->splice_read() expect -EAGAIN on
- * "can't put anything in there", rather than -EFAULT.
- */
- if (ret == -EFAULT)
- ret = -EAGAIN;
}
+ /*
+ * Callers of ->splice_read() expect -EAGAIN on "can't put anything in
+ * there", rather than -EFAULT.
+ */
+ if (ret == -EFAULT)
+ ret = -EAGAIN;
+
+ /* Free any pages that didn't get touched at all. */
+ if (keep < npages)
+ release_pages(pages + keep, npages - keep);
+
+ /* Push the remaining pages into the pipe. */
+ remain = ret;
+ for (i = 0; i < keep; i++) {
+ struct pipe_buffer *buf = pipe_head_buf(pipe);
+
+ chunk = min_t(size_t, remain, PAGE_SIZE);
+ *buf = (struct pipe_buffer) {
+ .ops = &default_pipe_buf_ops,
+ .page = bv[i].bv_page,
+ .offset = 0,
+ .len = chunk,
+ };
+ pipe->head++;
+ remain -= chunk;
+ }
+
+ kfree(bv);
return ret;
}
-EXPORT_SYMBOL(generic_file_splice_read);
+EXPORT_SYMBOL(copy_splice_read);
const struct pipe_buf_operations default_pipe_buf_ops = {
.release = generic_pipe_buf_release,
};
EXPORT_SYMBOL(nosteal_pipe_buf_ops);
-/*
- * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
- * using sendpage(). Return the number of bytes sent.
- */
-static int pipe_to_sendpage(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf, struct splice_desc *sd)
-{
- struct file *file = sd->u.file;
- loff_t pos = sd->pos;
- int more;
-
- if (!likely(file->f_op->sendpage))
- return -EINVAL;
-
- more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0;
-
- if (sd->len < sd->total_len &&
- pipe_occupancy(pipe->head, pipe->tail) > 1)
- more |= MSG_SENDPAGE_NOTLAST;
-
- return file->f_op->sendpage(file, buf->page, buf->offset,
- sd->len, &pos, more);
-}
-
static void wakeup_pipe_writers(struct pipe_inode_info *pipe)
{
smp_mb();
* Description:
* This function does little more than loop over the pipe and call
* @actor to do the actual moving of a single struct pipe_buffer to
- * the desired destination. See pipe_to_file, pipe_to_sendpage, or
+ * the desired destination. See pipe_to_file, pipe_to_sendmsg, or
* pipe_to_user.
*
*/
.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;
splice_from_pipe_begin(&sd);
while (sd.total_len) {
+ struct kiocb kiocb;
struct iov_iter from;
unsigned int head, tail, mask;
size_t left;
goto done;
}
- array[n].bv_page = buf->page;
- array[n].bv_len = this_len;
- array[n].bv_offset = buf->offset;
+ bvec_set_page(&array[n], buf->page, this_len,
+ buf->offset);
left -= this_len;
n++;
}
- iov_iter_bvec(&from, WRITE, array, n, sd.total_len - left);
- ret = vfs_iter_write(out, &from, &sd.pos, 0);
+ iov_iter_bvec(&from, ITER_SOURCE, array, n, sd.total_len - left);
+ 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;
EXPORT_SYMBOL(iter_file_splice_write);
+#ifdef CONFIG_NET
/**
- * generic_splice_sendpage - splice data from a pipe to a socket
+ * splice_to_socket - splice data from a pipe to a socket
* @pipe: pipe to splice from
* @out: socket to write to
* @ppos: position in @out
* is involved.
*
*/
-ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out,
- loff_t *ppos, size_t len, unsigned int flags)
+ssize_t splice_to_socket(struct pipe_inode_info *pipe, struct file *out,
+ loff_t *ppos, size_t len, unsigned int flags)
{
- return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage);
-}
+ struct socket *sock = sock_from_file(out);
+ struct bio_vec bvec[16];
+ struct msghdr msg = {};
+ ssize_t ret = 0;
+ size_t spliced = 0;
+ bool need_wakeup = false;
+
+ pipe_lock(pipe);
+
+ while (len > 0) {
+ unsigned int head, tail, mask, bc = 0;
+ size_t remain = len;
+
+ /*
+ * Check for signal early to make process killable when there
+ * are always buffers available
+ */
+ ret = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+
+ while (pipe_empty(pipe->head, pipe->tail)) {
+ ret = 0;
+ if (!pipe->writers)
+ goto out;
+
+ if (spliced)
+ goto out;
+
+ ret = -EAGAIN;
+ if (flags & SPLICE_F_NONBLOCK)
+ goto out;
+
+ ret = -ERESTARTSYS;
+ if (signal_pending(current))
+ goto out;
+
+ if (need_wakeup) {
+ wakeup_pipe_writers(pipe);
+ need_wakeup = false;
+ }
+
+ pipe_wait_readable(pipe);
+ }
+
+ head = pipe->head;
+ tail = pipe->tail;
+ mask = pipe->ring_size - 1;
+
+ while (!pipe_empty(head, tail)) {
+ struct pipe_buffer *buf = &pipe->bufs[tail & mask];
+ size_t seg;
+
+ if (!buf->len) {
+ tail++;
+ continue;
+ }
+
+ seg = min_t(size_t, remain, buf->len);
+
+ ret = pipe_buf_confirm(pipe, buf);
+ if (unlikely(ret)) {
+ if (ret == -ENODATA)
+ ret = 0;
+ break;
+ }
+
+ bvec_set_page(&bvec[bc++], buf->page, seg, buf->offset);
+ remain -= seg;
+ if (remain == 0 || bc >= ARRAY_SIZE(bvec))
+ break;
+ tail++;
+ }
+
+ if (!bc)
+ break;
+
+ msg.msg_flags = MSG_SPLICE_PAGES;
+ if (flags & SPLICE_F_MORE)
+ msg.msg_flags |= MSG_MORE;
+ if (remain && pipe_occupancy(pipe->head, tail) > 0)
+ msg.msg_flags |= MSG_MORE;
+ if (out->f_flags & O_NONBLOCK)
+ msg.msg_flags |= MSG_DONTWAIT;
+
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, bvec, bc,
+ len - remain);
+ ret = sock_sendmsg(sock, &msg);
+ if (ret <= 0)
+ break;
+
+ spliced += ret;
+ len -= ret;
+ tail = pipe->tail;
+ while (ret > 0) {
+ struct pipe_buffer *buf = &pipe->bufs[tail & mask];
+ size_t seg = min_t(size_t, ret, buf->len);
-EXPORT_SYMBOL(generic_splice_sendpage);
+ buf->offset += seg;
+ buf->len -= seg;
+ ret -= seg;
+
+ if (!buf->len) {
+ pipe_buf_release(pipe, buf);
+ tail++;
+ }
+ }
+
+ if (tail != pipe->tail) {
+ pipe->tail = tail;
+ if (pipe->files)
+ need_wakeup = true;
+ }
+ }
+
+out:
+ pipe_unlock(pipe);
+ if (need_wakeup)
+ wakeup_pipe_writers(pipe);
+ return spliced ?: ret;
+}
+#endif
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");
}
/*
- * Attempt to initiate a splice from a file to a pipe.
+ * Indicate to the caller that there was a premature EOF when reading from the
+ * source and the caller didn't indicate they would be sending more data after
+ * this.
+ */
+static void do_splice_eof(struct splice_desc *sd)
+{
+ if (sd->splice_eof)
+ sd->splice_eof(sd);
+}
+
+/*
+ * Callers already called rw_verify_area() on the entire range.
+ * No need to call it for sub ranges.
*/
-static long do_splice_to(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;
+ if (!len)
+ return 0;
/* Don't try to read more the pipe has space for. */
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;
if (unlikely(!in->f_op->splice_read))
return warn_unsupported(in, "read");
+ /*
+ * O_DIRECT and DAX don't deal with the pagecache, so we allocate a
+ * buffer, copy into it and splice that into the pipe.
+ */
+ if ((in->f_flags & O_DIRECT) || IS_DAX(in->f_mapping->host))
+ 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);
+
/**
* splice_direct_to_actor - splices data directly between two non-pipes
* @in: file to splice from
splice_direct_actor *actor)
{
struct pipe_inode_info *pipe;
- long ret, bytes;
+ ssize_t ret, bytes;
size_t len;
int i, flags, more;
/*
* Do the splice.
*/
- ret = 0;
bytes = 0;
len = sd->total_len;
+
+ /* Don't block on output, we have to drain the direct pipe. */
flags = sd->flags;
+ sd->flags &= ~SPLICE_F_NONBLOCK;
/*
- * Don't block on output, we have to drain the direct pipe.
+ * We signal MORE until we've read sufficient data to fulfill the
+ * request and we keep signalling it if the caller set it.
*/
- sd->flags &= ~SPLICE_F_NONBLOCK;
more = sd->flags & SPLICE_F_MORE;
+ sd->flags |= SPLICE_F_MORE;
WARN_ON_ONCE(!pipe_empty(pipe->head, pipe->tail));
size_t read_len;
loff_t pos = sd->pos, prev_pos = pos;
- ret = do_splice_to(in, &pos, pipe, len, flags);
+ ret = do_splice_read(in, &pos, pipe, len, flags);
if (unlikely(ret <= 0))
- goto out_release;
+ goto read_failure;
read_len = ret;
sd->total_len = read_len;
/*
- * If more data is pending, set SPLICE_F_MORE
- * If this is the last data and SPLICE_F_MORE was not set
- * initially, clears it.
+ * If we now have sufficient data to fulfill the request then
+ * we clear SPLICE_F_MORE if it was not set initially.
*/
- if (read_len < len)
- sd->flags |= SPLICE_F_MORE;
- else if (!more)
+ if (read_len >= len && !more)
sd->flags &= ~SPLICE_F_MORE;
+
/*
* NOTE: nonblocking mode only applies to the input. We
* must not do the output in nonblocking mode as then we
file_accessed(in);
return bytes;
+read_failure:
+ /*
+ * If the user did *not* set SPLICE_F_MORE *and* we didn't hit that
+ * "use all of len" case that cleared SPLICE_F_MORE, *and* we did a
+ * "->splice_in()" that returned EOF (ie zero) *and* we have sent at
+ * least 1 byte *then* we will also do the ->splice_eof() call.
+ */
+ if (ret == 0 && !more && len > 0 && bytes)
+ do_splice_eof(sd);
out_release:
/*
* If we did an incomplete transfer we must release
struct splice_desc *sd)
{
struct file *file = sd->u.file;
+ long ret;
- return do_splice_from(pipe, file, sd->opos, sd->total_len,
- sd->flags);
+ file_start_write(file);
+ ret = do_splice_from(pipe, file, sd->opos, sd->total_len, sd->flags);
+ file_end_write(file);
+ 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.
- *
- */
-long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
- loff_t *opos, size_t len, unsigned int flags)
+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);
+}
+
+static void direct_file_splice_eof(struct splice_desc *sd)
+{
+ struct file *file = sd->u.file;
+
+ if (file->f_op->splice_eof)
+ file->f_op->splice_eof(file);
+}
+
+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,
.flags = flags,
.pos = *ppos,
.u.file = out,
+ .splice_eof = direct_file_splice_eof,
.opos = opos,
};
- long ret;
+ ssize_t ret;
if (unlikely(!(out->f_mode & FMODE_WRITE)))
return -EBADF;
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 (;;) {
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 = do_splice_to(in, offset, opipe, len, flags);
+ ret = do_splice_read(in, offset, opipe, len, flags);
pipe_unlock(opipe);
if (ret > 0)
wakeup_pipe_readers(opipe);
/*
* 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)))
if ((in->f_flags | out->f_flags) & O_NONBLOCK)
flags |= SPLICE_F_NONBLOCK;
- return splice_pipe_to_pipe(ipipe, opipe, len, flags);
- }
-
- if (ipipe) {
+ ret = splice_pipe_to_pipe(ipipe, opipe, len, flags);
+ } else if (ipipe) {
if (off_in)
return -ESPIPE;
if (off_out) {
out->f_pos = offset;
else
*off_out = offset;
-
- return ret;
- }
-
- if (opipe) {
+ } else if (opipe) {
if (off_out)
return -ESPIPE;
if (off_in) {
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;
ret = splice_file_to_pipe(in, opipe, &offset, len, flags);
+
if (!off_in)
in->f_pos = offset;
else
*off_in = offset;
+ } else {
+ ret = -EINVAL;
+ }
- return ret;
+ if (ret > 0) {
+ /*
+ * Generate modify out before access in:
+ * do_splice_from() may've already sent modify out,
+ * and this ensures the events get merged.
+ */
+ fsnotify_modify(out);
+ fsnotify_access(in);
}
- return -EINVAL;
+ 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);
- if (ipipe && off_in)
- return -ESPIPE;
- if (opipe && off_out)
- return -ESPIPE;
+ if (ipipe) {
+ if (off_in)
+ return -ESPIPE;
+ pipe_clear_nowait(in);
+ }
+ if (opipe) {
+ if (off_out)
+ return -ESPIPE;
+ pipe_clear_nowait(out);
+ }
if (off_out) {
if (copy_from_user(&offset, off_out, sizeof(loff_t)))
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;
- bool failed = false;
+ ssize_t ret = 0;
- while (iov_iter_count(from) && !failed) {
+ while (iov_iter_count(from)) {
struct page *pages[16];
- ssize_t copied;
+ ssize_t left;
size_t start;
- int n;
+ int i, n;
- copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start);
- if (copied <= 0) {
- ret = copied;
+ left = iov_iter_get_pages2(from, pages, ~0UL, 16, &start);
+ if (left <= 0) {
+ ret = left;
break;
}
- for (n = 0; copied; n++, start = 0) {
- int size = min_t(int, copied, PAGE_SIZE - start);
- if (!failed) {
- buf.page = pages[n];
- buf.offset = start;
- buf.len = size;
- ret = add_to_pipe(pipe, &buf);
- if (unlikely(ret < 0)) {
- failed = true;
- } else {
- iov_iter_advance(from, ret);
- total += ret;
- }
- } else {
- put_page(pages[n]);
+ n = DIV_ROUND_UP(left + start, PAGE_SIZE);
+ for (i = 0; i < n; i++) {
+ int size = min_t(int, left, PAGE_SIZE - start);
+
+ buf.page = pages[i];
+ buf.offset = start;
+ buf.len = size;
+ ret = add_to_pipe(pipe, &buf);
+ if (unlikely(ret < 0)) {
+ iov_iter_revert(from, left);
+ // this one got dropped by add_to_pipe()
+ while (++i < n)
+ put_page(pages[i]);
+ goto out;
}
- copied -= size;
+ total += ret;
+ left -= size;
+ start = 0;
}
}
+out:
return total ? total : ret;
}
* 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 = {
.flags = flags,
.u.data = iter
};
- long ret = 0;
+ ssize_t ret = 0;
if (!pipe)
return -EBADF;
+ pipe_clear_nowait(file);
+
if (sd.total_len) {
pipe_lock(pipe);
ret = __splice_from_pipe(pipe, &sd, pipe_to_user);
pipe_unlock(pipe);
}
+ if (ret > 0)
+ fsnotify_access(file);
+
return ret;
}
* 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)
if (!pipe)
return -EBADF;
+ pipe_clear_nowait(file);
+
pipe_lock(pipe);
ret = wait_for_space(pipe, flags);
if (!ret)
ret = iter_to_pipe(iter, pipe, buf_flag);
pipe_unlock(pipe);
- if (ret > 0)
+ if (ret > 0) {
wakeup_pipe_readers(pipe);
+ fsnotify_modify(file);
+ }
return ret;
}
if (!f.file)
return -EBADF;
if (f.file->f_mode & FMODE_WRITE) {
- *type = WRITE;
+ *type = ITER_SOURCE;
} else if (f.file->f_mode & FMODE_READ) {
- *type = READ;
+ *type = ITER_DEST;
} else {
fdput(f);
return -EBADF;
if (!iov_iter_count(&iter))
error = 0;
- else if (iov_iter_rw(&iter) == WRITE)
+ else if (type == ITER_SOURCE)
error = vmsplice_to_pipe(f.file, &iter, flags);
else
error = vmsplice_to_user(f.file, &iter, flags);
size_t, len, unsigned int, flags)
{
struct fd in, out;
- long error;
+ ssize_t error;
if (unlikely(!len))
return 0;
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);
/*
* 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
* 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)))
}
}
+ if (ret > 0) {
+ fsnotify_access(in);
+ fsnotify_modify(out);
+ }
+
return ret;
}
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;