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@@ -125,12 +125,19 @@ static void page_cache_pipe_buf_unmap(struct pipe_inode_info *info,
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kunmap(buf->page);
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kunmap(buf->page);
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}
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}
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+static void page_cache_pipe_buf_get(struct pipe_inode_info *info,
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+ struct pipe_buffer *buf)
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+{
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+ page_cache_get(buf->page);
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+}
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+
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static struct pipe_buf_operations page_cache_pipe_buf_ops = {
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static struct pipe_buf_operations page_cache_pipe_buf_ops = {
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.can_merge = 0,
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.can_merge = 0,
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.map = page_cache_pipe_buf_map,
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.map = page_cache_pipe_buf_map,
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.unmap = page_cache_pipe_buf_unmap,
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.unmap = page_cache_pipe_buf_unmap,
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.release = page_cache_pipe_buf_release,
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.release = page_cache_pipe_buf_release,
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.steal = page_cache_pipe_buf_steal,
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.steal = page_cache_pipe_buf_steal,
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+ .get = page_cache_pipe_buf_get,
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};
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};
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/*
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/*
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@@ -231,8 +238,9 @@ static ssize_t move_to_pipe(struct pipe_inode_info *pipe, struct page **pages,
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}
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}
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static int
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static int
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-__generic_file_splice_read(struct file *in, struct pipe_inode_info *pipe,
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- size_t len, unsigned int flags)
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+__generic_file_splice_read(struct file *in, loff_t *ppos,
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+ struct pipe_inode_info *pipe, size_t len,
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+ unsigned int flags)
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{
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{
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struct address_space *mapping = in->f_mapping;
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struct address_space *mapping = in->f_mapping;
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unsigned int offset, nr_pages;
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unsigned int offset, nr_pages;
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@@ -241,8 +249,8 @@ __generic_file_splice_read(struct file *in, struct pipe_inode_info *pipe,
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pgoff_t index;
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pgoff_t index;
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int i, error;
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int i, error;
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- index = in->f_pos >> PAGE_CACHE_SHIFT;
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- offset = in->f_pos & ~PAGE_CACHE_MASK;
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+ index = *ppos >> PAGE_CACHE_SHIFT;
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+ offset = *ppos & ~PAGE_CACHE_MASK;
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nr_pages = (len + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
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nr_pages = (len + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
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if (nr_pages > PIPE_BUFFERS)
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if (nr_pages > PIPE_BUFFERS)
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@@ -348,8 +356,9 @@ fill_it:
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*
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*
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* Will read pages from given file and fill them into a pipe.
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* Will read pages from given file and fill them into a pipe.
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*/
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*/
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-ssize_t generic_file_splice_read(struct file *in, struct pipe_inode_info *pipe,
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- size_t len, unsigned int flags)
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+ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
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+ struct pipe_inode_info *pipe, size_t len,
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+ unsigned int flags)
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{
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{
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ssize_t spliced;
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ssize_t spliced;
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int ret;
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int ret;
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@@ -358,12 +367,12 @@ ssize_t generic_file_splice_read(struct file *in, struct pipe_inode_info *pipe,
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spliced = 0;
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spliced = 0;
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while (len) {
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while (len) {
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- ret = __generic_file_splice_read(in, pipe, len, flags);
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+ ret = __generic_file_splice_read(in, ppos, pipe, len, flags);
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if (ret <= 0)
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if (ret <= 0)
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break;
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break;
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- in->f_pos += ret;
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+ *ppos += ret;
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len -= ret;
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len -= ret;
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spliced += ret;
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spliced += ret;
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@@ -561,7 +570,7 @@ typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
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* to the wanted destination. See pipe_to_file/pipe_to_sendpage above.
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* to the wanted destination. See pipe_to_file/pipe_to_sendpage above.
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*/
|
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*/
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static ssize_t move_from_pipe(struct pipe_inode_info *pipe, struct file *out,
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static ssize_t move_from_pipe(struct pipe_inode_info *pipe, struct file *out,
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- size_t len, unsigned int flags,
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|
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+ loff_t *ppos, size_t len, unsigned int flags,
|
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splice_actor *actor)
|
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splice_actor *actor)
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{
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{
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int ret, do_wakeup, err;
|
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int ret, do_wakeup, err;
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@@ -573,7 +582,7 @@ static ssize_t move_from_pipe(struct pipe_inode_info *pipe, struct file *out,
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sd.total_len = len;
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sd.total_len = len;
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sd.flags = flags;
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sd.flags = flags;
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sd.file = out;
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sd.file = out;
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- sd.pos = out->f_pos;
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+ sd.pos = *ppos;
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|
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if (pipe->inode)
|
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if (pipe->inode)
|
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mutex_lock(&pipe->inode->i_mutex);
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mutex_lock(&pipe->inode->i_mutex);
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@@ -656,9 +665,7 @@ static ssize_t move_from_pipe(struct pipe_inode_info *pipe, struct file *out,
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kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
|
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kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
|
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}
|
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}
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- out->f_pos = sd.pos;
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return ret;
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return ret;
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-
|
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}
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}
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|
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/**
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/**
|
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@@ -674,12 +681,12 @@ static ssize_t move_from_pipe(struct pipe_inode_info *pipe, struct file *out,
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*/
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*/
|
|
ssize_t
|
|
ssize_t
|
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generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
|
|
generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
|
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- size_t len, unsigned int flags)
|
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|
|
|
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+ loff_t *ppos, size_t len, unsigned int flags)
|
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{
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|
{
|
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struct address_space *mapping = out->f_mapping;
|
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struct address_space *mapping = out->f_mapping;
|
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ssize_t ret;
|
|
ssize_t ret;
|
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|
|
|
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- ret = move_from_pipe(pipe, out, len, flags, pipe_to_file);
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|
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+ ret = move_from_pipe(pipe, out, ppos, len, flags, pipe_to_file);
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|
|
|
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/*
|
|
/*
|
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* If file or inode is SYNC and we actually wrote some data, sync it.
|
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* If file or inode is SYNC and we actually wrote some data, sync it.
|
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@@ -715,9 +722,9 @@ EXPORT_SYMBOL(generic_file_splice_write);
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*
|
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*
|
|
*/
|
|
*/
|
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ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out,
|
|
ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out,
|
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- size_t len, unsigned int flags)
|
|
|
|
|
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+ loff_t *ppos, size_t len, unsigned int flags)
|
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{
|
|
{
|
|
- return move_from_pipe(pipe, out, len, flags, pipe_to_sendpage);
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|
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|
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+ return move_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage);
|
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}
|
|
}
|
|
|
|
|
|
EXPORT_SYMBOL(generic_splice_sendpage);
|
|
EXPORT_SYMBOL(generic_splice_sendpage);
|
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@@ -726,9 +733,8 @@ EXPORT_SYMBOL(generic_splice_sendpage);
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* Attempt to initiate a splice from pipe to file.
|
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* Attempt to initiate a splice from pipe to file.
|
|
*/
|
|
*/
|
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static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
|
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static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
|
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- size_t len, unsigned int flags)
|
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|
|
|
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+ loff_t *ppos, size_t len, unsigned int flags)
|
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{
|
|
{
|
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- loff_t pos;
|
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|
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int ret;
|
|
int ret;
|
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|
|
|
|
if (unlikely(!out->f_op || !out->f_op->splice_write))
|
|
if (unlikely(!out->f_op || !out->f_op->splice_write))
|
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@@ -737,22 +743,21 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
|
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if (unlikely(!(out->f_mode & FMODE_WRITE)))
|
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if (unlikely(!(out->f_mode & FMODE_WRITE)))
|
|
return -EBADF;
|
|
return -EBADF;
|
|
|
|
|
|
- pos = out->f_pos;
|
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|
|
-
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|
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- ret = rw_verify_area(WRITE, out, &pos, len);
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|
|
|
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+ ret = rw_verify_area(WRITE, out, ppos, len);
|
|
if (unlikely(ret < 0))
|
|
if (unlikely(ret < 0))
|
|
return ret;
|
|
return ret;
|
|
|
|
|
|
- return out->f_op->splice_write(pipe, out, len, flags);
|
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|
|
|
|
+ return out->f_op->splice_write(pipe, out, ppos, len, flags);
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
/*
|
|
* Attempt to initiate a splice from a file to a pipe.
|
|
* Attempt to initiate a splice from a file to a pipe.
|
|
*/
|
|
*/
|
|
-static long do_splice_to(struct file *in, struct pipe_inode_info *pipe,
|
|
|
|
- size_t len, unsigned int flags)
|
|
|
|
|
|
+static long do_splice_to(struct file *in, loff_t *ppos,
|
|
|
|
+ struct pipe_inode_info *pipe, size_t len,
|
|
|
|
+ unsigned int flags)
|
|
{
|
|
{
|
|
- loff_t pos, isize, left;
|
|
|
|
|
|
+ loff_t isize, left;
|
|
int ret;
|
|
int ret;
|
|
|
|
|
|
if (unlikely(!in->f_op || !in->f_op->splice_read))
|
|
if (unlikely(!in->f_op || !in->f_op->splice_read))
|
|
@@ -761,28 +766,27 @@ static long do_splice_to(struct file *in, struct pipe_inode_info *pipe,
|
|
if (unlikely(!(in->f_mode & FMODE_READ)))
|
|
if (unlikely(!(in->f_mode & FMODE_READ)))
|
|
return -EBADF;
|
|
return -EBADF;
|
|
|
|
|
|
- pos = in->f_pos;
|
|
|
|
-
|
|
|
|
- ret = rw_verify_area(READ, in, &pos, len);
|
|
|
|
|
|
+ ret = rw_verify_area(READ, in, ppos, len);
|
|
if (unlikely(ret < 0))
|
|
if (unlikely(ret < 0))
|
|
return ret;
|
|
return ret;
|
|
|
|
|
|
isize = i_size_read(in->f_mapping->host);
|
|
isize = i_size_read(in->f_mapping->host);
|
|
- if (unlikely(in->f_pos >= isize))
|
|
|
|
|
|
+ if (unlikely(*ppos >= isize))
|
|
return 0;
|
|
return 0;
|
|
|
|
|
|
- left = isize - in->f_pos;
|
|
|
|
|
|
+ left = isize - *ppos;
|
|
if (unlikely(left < len))
|
|
if (unlikely(left < len))
|
|
len = left;
|
|
len = left;
|
|
|
|
|
|
- return in->f_op->splice_read(in, pipe, len, flags);
|
|
|
|
|
|
+ return in->f_op->splice_read(in, ppos, pipe, len, flags);
|
|
}
|
|
}
|
|
|
|
|
|
-long do_splice_direct(struct file *in, struct file *out, size_t len,
|
|
|
|
- unsigned int flags)
|
|
|
|
|
|
+long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
|
|
|
|
+ size_t len, unsigned int flags)
|
|
{
|
|
{
|
|
struct pipe_inode_info *pipe;
|
|
struct pipe_inode_info *pipe;
|
|
long ret, bytes;
|
|
long ret, bytes;
|
|
|
|
+ loff_t out_off;
|
|
umode_t i_mode;
|
|
umode_t i_mode;
|
|
int i;
|
|
int i;
|
|
|
|
|
|
@@ -820,6 +824,7 @@ long do_splice_direct(struct file *in, struct file *out, size_t len,
|
|
*/
|
|
*/
|
|
ret = 0;
|
|
ret = 0;
|
|
bytes = 0;
|
|
bytes = 0;
|
|
|
|
+ out_off = 0;
|
|
|
|
|
|
while (len) {
|
|
while (len) {
|
|
size_t read_len, max_read_len;
|
|
size_t read_len, max_read_len;
|
|
@@ -829,7 +834,7 @@ long do_splice_direct(struct file *in, struct file *out, size_t len,
|
|
*/
|
|
*/
|
|
max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
|
|
max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
|
|
|
|
|
|
- ret = do_splice_to(in, pipe, max_read_len, flags);
|
|
|
|
|
|
+ ret = do_splice_to(in, ppos, pipe, max_read_len, flags);
|
|
if (unlikely(ret < 0))
|
|
if (unlikely(ret < 0))
|
|
goto out_release;
|
|
goto out_release;
|
|
|
|
|
|
@@ -840,7 +845,7 @@ long do_splice_direct(struct file *in, struct file *out, size_t len,
|
|
* must not do the output in nonblocking mode as then we
|
|
* must not do the output in nonblocking mode as then we
|
|
* could get stuck data in the internal pipe:
|
|
* could get stuck data in the internal pipe:
|
|
*/
|
|
*/
|
|
- ret = do_splice_from(pipe, out, read_len,
|
|
|
|
|
|
+ ret = do_splice_from(pipe, out, &out_off, read_len,
|
|
flags & ~SPLICE_F_NONBLOCK);
|
|
flags & ~SPLICE_F_NONBLOCK);
|
|
if (unlikely(ret < 0))
|
|
if (unlikely(ret < 0))
|
|
goto out_release;
|
|
goto out_release;
|
|
@@ -898,6 +903,7 @@ static long do_splice(struct file *in, loff_t __user *off_in,
|
|
size_t len, unsigned int flags)
|
|
size_t len, unsigned int flags)
|
|
{
|
|
{
|
|
struct pipe_inode_info *pipe;
|
|
struct pipe_inode_info *pipe;
|
|
|
|
+ loff_t offset, *off;
|
|
|
|
|
|
pipe = in->f_dentry->d_inode->i_pipe;
|
|
pipe = in->f_dentry->d_inode->i_pipe;
|
|
if (pipe) {
|
|
if (pipe) {
|
|
@@ -906,12 +912,13 @@ static long do_splice(struct file *in, loff_t __user *off_in,
|
|
if (off_out) {
|
|
if (off_out) {
|
|
if (out->f_op->llseek == no_llseek)
|
|
if (out->f_op->llseek == no_llseek)
|
|
return -EINVAL;
|
|
return -EINVAL;
|
|
- if (copy_from_user(&out->f_pos, off_out,
|
|
|
|
- sizeof(loff_t)))
|
|
|
|
|
|
+ if (copy_from_user(&offset, off_out, sizeof(loff_t)))
|
|
return -EFAULT;
|
|
return -EFAULT;
|
|
- }
|
|
|
|
|
|
+ off = &offset;
|
|
|
|
+ } else
|
|
|
|
+ off = &out->f_pos;
|
|
|
|
|
|
- return do_splice_from(pipe, out, len, flags);
|
|
|
|
|
|
+ return do_splice_from(pipe, out, off, len, flags);
|
|
}
|
|
}
|
|
|
|
|
|
pipe = out->f_dentry->d_inode->i_pipe;
|
|
pipe = out->f_dentry->d_inode->i_pipe;
|
|
@@ -921,11 +928,13 @@ static long do_splice(struct file *in, loff_t __user *off_in,
|
|
if (off_in) {
|
|
if (off_in) {
|
|
if (in->f_op->llseek == no_llseek)
|
|
if (in->f_op->llseek == no_llseek)
|
|
return -EINVAL;
|
|
return -EINVAL;
|
|
- if (copy_from_user(&in->f_pos, off_in, sizeof(loff_t)))
|
|
|
|
|
|
+ if (copy_from_user(&offset, off_in, sizeof(loff_t)))
|
|
return -EFAULT;
|
|
return -EFAULT;
|
|
- }
|
|
|
|
|
|
+ off = &offset;
|
|
|
|
+ } else
|
|
|
|
+ off = &in->f_pos;
|
|
|
|
|
|
- return do_splice_to(in, pipe, len, flags);
|
|
|
|
|
|
+ return do_splice_to(in, off, pipe, len, flags);
|
|
}
|
|
}
|
|
|
|
|
|
return -EINVAL;
|
|
return -EINVAL;
|
|
@@ -961,3 +970,182 @@ asmlinkage long sys_splice(int fd_in, loff_t __user *off_in,
|
|
|
|
|
|
return error;
|
|
return error;
|
|
}
|
|
}
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * 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)
|
|
|
|
+{
|
|
|
|
+ struct pipe_buffer *ibuf, *obuf;
|
|
|
|
+ int ret = 0, do_wakeup = 0, i;
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * Potential ABBA deadlock, work around it by ordering lock
|
|
|
|
+ * grabbing by inode address. Otherwise two different processes
|
|
|
|
+ * could deadlock (one doing tee from A -> B, the other from B -> A).
|
|
|
|
+ */
|
|
|
|
+ if (ipipe->inode < opipe->inode) {
|
|
|
|
+ mutex_lock(&ipipe->inode->i_mutex);
|
|
|
|
+ mutex_lock(&opipe->inode->i_mutex);
|
|
|
|
+ } else {
|
|
|
|
+ mutex_lock(&opipe->inode->i_mutex);
|
|
|
|
+ mutex_lock(&ipipe->inode->i_mutex);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ for (i = 0;; i++) {
|
|
|
|
+ if (!opipe->readers) {
|
|
|
|
+ send_sig(SIGPIPE, current, 0);
|
|
|
|
+ if (!ret)
|
|
|
|
+ ret = -EPIPE;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ if (ipipe->nrbufs - i) {
|
|
|
|
+ ibuf = ipipe->bufs + ((ipipe->curbuf + i) & (PIPE_BUFFERS - 1));
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * If we have room, fill this buffer
|
|
|
|
+ */
|
|
|
|
+ if (opipe->nrbufs < PIPE_BUFFERS) {
|
|
|
|
+ int nbuf = (opipe->curbuf + opipe->nrbufs) & (PIPE_BUFFERS - 1);
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * Get a reference to this pipe buffer,
|
|
|
|
+ * so we can copy the contents over.
|
|
|
|
+ */
|
|
|
|
+ ibuf->ops->get(ipipe, ibuf);
|
|
|
|
+
|
|
|
|
+ obuf = opipe->bufs + nbuf;
|
|
|
|
+ *obuf = *ibuf;
|
|
|
|
+
|
|
|
|
+ if (obuf->len > len)
|
|
|
|
+ obuf->len = len;
|
|
|
|
+
|
|
|
|
+ opipe->nrbufs++;
|
|
|
|
+ do_wakeup = 1;
|
|
|
|
+ ret += obuf->len;
|
|
|
|
+ len -= obuf->len;
|
|
|
|
+
|
|
|
|
+ if (!len)
|
|
|
|
+ break;
|
|
|
|
+ if (opipe->nrbufs < PIPE_BUFFERS)
|
|
|
|
+ continue;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * We have input available, but no output room.
|
|
|
|
+ * If we already copied data, return that.
|
|
|
|
+ */
|
|
|
|
+ if (flags & SPLICE_F_NONBLOCK) {
|
|
|
|
+ if (!ret)
|
|
|
|
+ ret = -EAGAIN;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ if (signal_pending(current)) {
|
|
|
|
+ if (!ret)
|
|
|
|
+ ret = -ERESTARTSYS;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ if (do_wakeup) {
|
|
|
|
+ smp_mb();
|
|
|
|
+ if (waitqueue_active(&opipe->wait))
|
|
|
|
+ wake_up_interruptible(&opipe->wait);
|
|
|
|
+ kill_fasync(&opipe->fasync_readers, SIGIO, POLL_IN);
|
|
|
|
+ do_wakeup = 0;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ opipe->waiting_writers++;
|
|
|
|
+ pipe_wait(opipe);
|
|
|
|
+ opipe->waiting_writers--;
|
|
|
|
+ continue;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * No input buffers, do the usual checks for available
|
|
|
|
+ * writers and blocking and wait if necessary
|
|
|
|
+ */
|
|
|
|
+ if (!ipipe->writers)
|
|
|
|
+ break;
|
|
|
|
+ if (!ipipe->waiting_writers) {
|
|
|
|
+ if (ret)
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ if (flags & SPLICE_F_NONBLOCK) {
|
|
|
|
+ if (!ret)
|
|
|
|
+ ret = -EAGAIN;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+ if (signal_pending(current)) {
|
|
|
|
+ if (!ret)
|
|
|
|
+ ret = -ERESTARTSYS;
|
|
|
|
+ break;
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ if (waitqueue_active(&ipipe->wait))
|
|
|
|
+ wake_up_interruptible_sync(&ipipe->wait);
|
|
|
|
+ kill_fasync(&ipipe->fasync_writers, SIGIO, POLL_OUT);
|
|
|
|
+
|
|
|
|
+ pipe_wait(ipipe);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ mutex_unlock(&ipipe->inode->i_mutex);
|
|
|
|
+ mutex_unlock(&opipe->inode->i_mutex);
|
|
|
|
+
|
|
|
|
+ if (do_wakeup) {
|
|
|
|
+ smp_mb();
|
|
|
|
+ if (waitqueue_active(&opipe->wait))
|
|
|
|
+ wake_up_interruptible(&opipe->wait);
|
|
|
|
+ kill_fasync(&opipe->fasync_readers, SIGIO, POLL_IN);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ return ret;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+/*
|
|
|
|
+ * This is a tee(1) implementation that works on pipes. It doesn't copy
|
|
|
|
+ * any data, it simply references the 'in' pages on the 'out' pipe.
|
|
|
|
+ * The 'flags' used are the SPLICE_F_* variants, currently the only
|
|
|
|
+ * applicable one is SPLICE_F_NONBLOCK.
|
|
|
|
+ */
|
|
|
|
+static long do_tee(struct file *in, struct file *out, size_t len,
|
|
|
|
+ unsigned int flags)
|
|
|
|
+{
|
|
|
|
+ struct pipe_inode_info *ipipe = in->f_dentry->d_inode->i_pipe;
|
|
|
|
+ struct pipe_inode_info *opipe = out->f_dentry->d_inode->i_pipe;
|
|
|
|
+
|
|
|
|
+ /*
|
|
|
|
+ * Link ipipe to the two output pipes, consuming as we go along.
|
|
|
|
+ */
|
|
|
|
+ if (ipipe && opipe)
|
|
|
|
+ return link_pipe(ipipe, opipe, len, flags);
|
|
|
|
+
|
|
|
|
+ return -EINVAL;
|
|
|
|
+}
|
|
|
|
+
|
|
|
|
+asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags)
|
|
|
|
+{
|
|
|
|
+ struct file *in;
|
|
|
|
+ int error, fput_in;
|
|
|
|
+
|
|
|
|
+ if (unlikely(!len))
|
|
|
|
+ return 0;
|
|
|
|
+
|
|
|
|
+ error = -EBADF;
|
|
|
|
+ in = fget_light(fdin, &fput_in);
|
|
|
|
+ if (in) {
|
|
|
|
+ if (in->f_mode & FMODE_READ) {
|
|
|
|
+ int fput_out;
|
|
|
|
+ struct file *out = fget_light(fdout, &fput_out);
|
|
|
|
+
|
|
|
|
+ if (out) {
|
|
|
|
+ if (out->f_mode & FMODE_WRITE)
|
|
|
|
+ error = do_tee(in, out, len, flags);
|
|
|
|
+ fput_light(out, fput_out);
|
|
|
|
+ }
|
|
|
|
+ }
|
|
|
|
+ fput_light(in, fput_in);
|
|
|
|
+ }
|
|
|
|
+
|
|
|
|
+ return error;
|
|
|
|
+}
|