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@@ -9,11 +9,12 @@
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* that transfers data buffers to or from a pipe buffer.
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*
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* Named by Larry McVoy, original implementation from Linus, extended by
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- * Jens to support splicing to files and fixing the initial implementation
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- * bugs.
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+ * Jens to support splicing to files, network, direct splicing, etc and
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+ * fixing lots of bugs.
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*
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- * Copyright (C) 2005 Jens Axboe <axboe@suse.de>
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- * Copyright (C) 2005 Linus Torvalds <torvalds@osdl.org>
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+ * Copyright (C) 2005-2006 Jens Axboe <axboe@suse.de>
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+ * Copyright (C) 2005-2006 Linus Torvalds <torvalds@osdl.org>
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+ * Copyright (C) 2006 Ingo Molnar <mingo@elte.hu>
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*
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*/
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#include <linux/fs.h>
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@@ -84,26 +85,43 @@ static void *page_cache_pipe_buf_map(struct file *file,
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struct pipe_buffer *buf)
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{
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struct page *page = buf->page;
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-
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- lock_page(page);
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+ int err;
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if (!PageUptodate(page)) {
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- unlock_page(page);
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- return ERR_PTR(-EIO);
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- }
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+ lock_page(page);
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+
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+ /*
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+ * Page got truncated/unhashed. This will cause a 0-byte
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+ * splice, if this is the first page.
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+ */
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+ if (!page->mapping) {
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+ err = -ENODATA;
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+ goto error;
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+ }
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- if (!page->mapping) {
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+ /*
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+ * Uh oh, read-error from disk.
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+ */
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+ if (!PageUptodate(page)) {
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+ err = -EIO;
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+ goto error;
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+ }
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+
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+ /*
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+ * Page is ok afterall, fall through to mapping.
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+ */
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unlock_page(page);
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- return ERR_PTR(-ENODATA);
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}
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- return kmap(buf->page);
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+ return kmap(page);
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+error:
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+ unlock_page(page);
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+ return ERR_PTR(err);
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}
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static void page_cache_pipe_buf_unmap(struct pipe_inode_info *info,
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struct pipe_buffer *buf)
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{
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- unlock_page(buf->page);
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kunmap(buf->page);
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}
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@@ -119,34 +137,30 @@ static struct pipe_buf_operations page_cache_pipe_buf_ops = {
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* Pipe output worker. This sets up our pipe format with the page cache
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* pipe buffer operations. Otherwise very similar to the regular pipe_writev().
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*/
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-static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
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+static ssize_t move_to_pipe(struct pipe_inode_info *pipe, struct page **pages,
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int nr_pages, unsigned long offset,
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unsigned long len, unsigned int flags)
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{
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- struct pipe_inode_info *info;
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int ret, do_wakeup, i;
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ret = 0;
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do_wakeup = 0;
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i = 0;
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- mutex_lock(PIPE_MUTEX(*inode));
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+ if (pipe->inode)
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+ mutex_lock(&pipe->inode->i_mutex);
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- info = inode->i_pipe;
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for (;;) {
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- int bufs;
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-
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- if (!PIPE_READERS(*inode)) {
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+ if (!pipe->readers) {
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send_sig(SIGPIPE, current, 0);
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if (!ret)
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ret = -EPIPE;
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break;
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}
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- bufs = info->nrbufs;
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- if (bufs < PIPE_BUFFERS) {
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- int newbuf = (info->curbuf + bufs) & (PIPE_BUFFERS - 1);
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- struct pipe_buffer *buf = info->bufs + newbuf;
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+ if (pipe->nrbufs < PIPE_BUFFERS) {
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+ int newbuf = (pipe->curbuf + pipe->nrbufs) & (PIPE_BUFFERS - 1);
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+ struct pipe_buffer *buf = pipe->bufs + newbuf;
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struct page *page = pages[i++];
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unsigned long this_len;
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@@ -158,8 +172,9 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
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buf->offset = offset;
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buf->len = this_len;
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buf->ops = &page_cache_pipe_buf_ops;
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- info->nrbufs = ++bufs;
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- do_wakeup = 1;
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+ pipe->nrbufs++;
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+ if (pipe->inode)
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+ do_wakeup = 1;
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ret += this_len;
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len -= this_len;
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@@ -168,7 +183,7 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
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break;
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if (!len)
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break;
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- if (bufs < PIPE_BUFFERS)
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+ if (pipe->nrbufs < PIPE_BUFFERS)
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continue;
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break;
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@@ -187,22 +202,26 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
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}
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if (do_wakeup) {
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- wake_up_interruptible_sync(PIPE_WAIT(*inode));
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- kill_fasync(PIPE_FASYNC_READERS(*inode), SIGIO,
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- POLL_IN);
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+ smp_mb();
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+ if (waitqueue_active(&pipe->wait))
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+ wake_up_interruptible_sync(&pipe->wait);
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+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
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do_wakeup = 0;
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}
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- PIPE_WAITING_WRITERS(*inode)++;
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- pipe_wait(inode);
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- PIPE_WAITING_WRITERS(*inode)--;
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+ pipe->waiting_writers++;
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+ pipe_wait(pipe);
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+ pipe->waiting_writers--;
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}
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- mutex_unlock(PIPE_MUTEX(*inode));
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+ if (pipe->inode)
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+ mutex_unlock(&pipe->inode->i_mutex);
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if (do_wakeup) {
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- wake_up_interruptible(PIPE_WAIT(*inode));
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- kill_fasync(PIPE_FASYNC_READERS(*inode), SIGIO, POLL_IN);
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+ smp_mb();
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+ if (waitqueue_active(&pipe->wait))
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+ wake_up_interruptible(&pipe->wait);
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+ kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
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}
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while (i < nr_pages)
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@@ -211,15 +230,16 @@ static ssize_t move_to_pipe(struct inode *inode, struct page **pages,
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return ret;
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}
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-static int __generic_file_splice_read(struct file *in, struct inode *pipe,
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- size_t len, unsigned int flags)
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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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{
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struct address_space *mapping = in->f_mapping;
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unsigned int offset, nr_pages;
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- struct page *pages[PIPE_BUFFERS], *shadow[PIPE_BUFFERS];
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+ struct page *pages[PIPE_BUFFERS];
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struct page *page;
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- pgoff_t index, pidx;
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- int i, j;
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+ pgoff_t index;
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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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@@ -229,78 +249,94 @@ static int __generic_file_splice_read(struct file *in, struct inode *pipe,
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nr_pages = PIPE_BUFFERS;
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/*
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- * initiate read-ahead on this page range
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- */
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- do_page_cache_readahead(mapping, in, index, nr_pages);
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-
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- /*
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- * Get as many pages from the page cache as possible..
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- * Start IO on the page cache entries we create (we
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- * can assume that any pre-existing ones we find have
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- * already had IO started on them).
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+ * Initiate read-ahead on this page range. however, don't call into
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+ * read-ahead if this is a non-zero offset (we are likely doing small
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+ * chunk splice and the page is already there) for a single page.
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*/
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- i = find_get_pages(mapping, index, nr_pages, pages);
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+ if (!offset || nr_pages > 1)
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+ do_page_cache_readahead(mapping, in, index, nr_pages);
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/*
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- * common case - we found all pages and they are contiguous,
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- * kick them off
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+ * Now fill in the holes:
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*/
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- if (i && (pages[i - 1]->index == index + i - 1))
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- goto splice_them;
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+ error = 0;
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+ for (i = 0; i < nr_pages; i++, index++) {
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+find_page:
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+ /*
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+ * lookup the page for this index
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+ */
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+ page = find_get_page(mapping, index);
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+ if (!page) {
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+ /*
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+ * If in nonblock mode then dont block on
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+ * readpage (we've kicked readahead so there
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+ * will be asynchronous progress):
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+ */
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+ if (flags & SPLICE_F_NONBLOCK)
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+ break;
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- /*
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- * fill shadow[] with pages at the right locations, so we only
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- * have to fill holes
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- */
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- memset(shadow, 0, nr_pages * sizeof(struct page *));
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- for (j = 0; j < i; j++)
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- shadow[pages[j]->index - index] = pages[j];
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+ /*
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+ * page didn't exist, allocate one
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+ */
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+ page = page_cache_alloc_cold(mapping);
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+ if (!page)
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+ break;
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- /*
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- * now fill in the holes
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- */
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- for (i = 0, pidx = index; i < nr_pages; pidx++, i++) {
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- int error;
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+ error = add_to_page_cache_lru(page, mapping, index,
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+ mapping_gfp_mask(mapping));
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+ if (unlikely(error)) {
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+ page_cache_release(page);
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+ break;
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+ }
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- if (shadow[i])
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- continue;
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+ goto readpage;
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+ }
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/*
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- * no page there, look one up / create it
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+ * If the page isn't uptodate, we may need to start io on it
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*/
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- page = find_or_create_page(mapping, pidx,
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- mapping_gfp_mask(mapping));
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- if (!page)
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- break;
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+ if (!PageUptodate(page)) {
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+ lock_page(page);
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+
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+ /*
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+ * page was truncated, stop here. if this isn't the
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+ * first page, we'll just complete what we already
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+ * added
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+ */
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+ if (!page->mapping) {
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+ unlock_page(page);
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+ page_cache_release(page);
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+ break;
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+ }
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+ /*
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+ * page was already under io and is now done, great
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+ */
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+ if (PageUptodate(page)) {
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+ unlock_page(page);
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+ goto fill_it;
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+ }
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- if (PageUptodate(page))
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- unlock_page(page);
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- else {
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+readpage:
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+ /*
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+ * need to read in the page
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+ */
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error = mapping->a_ops->readpage(in, page);
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if (unlikely(error)) {
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page_cache_release(page);
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+ if (error == AOP_TRUNCATED_PAGE)
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+ goto find_page;
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break;
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}
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}
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- shadow[i] = page;
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+fill_it:
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+ pages[i] = page;
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}
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- if (!i) {
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- for (i = 0; i < nr_pages; i++) {
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- if (shadow[i])
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- page_cache_release(shadow[i]);
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- }
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- return 0;
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- }
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+ if (i)
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+ return move_to_pipe(pipe, pages, i, offset, len, flags);
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- memcpy(pages, shadow, i * sizeof(struct page *));
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-
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- /*
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- * Now we splice them into the pipe..
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- */
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-splice_them:
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- return move_to_pipe(pipe, pages, i, offset, len, flags);
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+ return error;
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}
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/**
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@@ -311,9 +347,8 @@ splice_them:
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* @flags: splice modifier flags
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*
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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 inode *pipe,
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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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{
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ssize_t spliced;
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@@ -321,6 +356,7 @@ ssize_t generic_file_splice_read(struct file *in, struct inode *pipe,
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ret = 0;
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spliced = 0;
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+
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while (len) {
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ret = __generic_file_splice_read(in, pipe, len, flags);
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@@ -360,10 +396,10 @@ static int pipe_to_sendpage(struct pipe_inode_info *info,
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int more;
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/*
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- * sub-optimal, but we are limited by the pipe ->map. we don't
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+ * Sub-optimal, but we are limited by the pipe ->map. We don't
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* need a kmap'ed buffer here, we just want to make sure we
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* have the page pinned if the pipe page originates from the
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- * page cache
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+ * page cache.
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*/
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ptr = buf->ops->map(file, info, buf);
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if (IS_ERR(ptr))
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@@ -414,7 +450,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
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int ret;
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/*
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- * after this, page will be locked and unmapped
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+ * make sure the data in this buffer is uptodate
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*/
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src = buf->ops->map(file, info, buf);
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if (IS_ERR(src))
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@@ -424,7 +460,7 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
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offset = sd->pos & ~PAGE_CACHE_MASK;
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/*
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- * reuse buf page, if SPLICE_F_MOVE is set
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+ * Reuse buf page, if SPLICE_F_MOVE is set.
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*/
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if (sd->flags & SPLICE_F_MOVE) {
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/*
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@@ -434,6 +470,9 @@ static int pipe_to_file(struct pipe_inode_info *info, struct pipe_buffer *buf,
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if (buf->ops->steal(info, buf))
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goto find_page;
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+ /*
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+ * this will also set the page locked
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+ */
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page = buf->page;
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if (add_to_page_cache(page, mapping, index, gfp_mask))
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goto find_page;
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@@ -445,7 +484,7 @@ find_page:
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ret = -ENOMEM;
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page = find_or_create_page(mapping, index, gfp_mask);
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if (!page)
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- goto out;
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+ goto out_nomem;
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/*
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* If the page is uptodate, it is also locked. If it isn't
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@@ -462,7 +501,7 @@ find_page:
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if (!PageUptodate(page)) {
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/*
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- * page got invalidated, repeat
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+ * Page got invalidated, repeat.
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*/
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if (!page->mapping) {
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unlock_page(page);
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@@ -501,12 +540,14 @@ find_page:
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} else if (ret)
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goto out;
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+ mark_page_accessed(page);
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balance_dirty_pages_ratelimited(mapping);
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out:
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if (!(buf->flags & PIPE_BUF_FLAG_STOLEN)) {
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page_cache_release(page);
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unlock_page(page);
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}
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+out_nomem:
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buf->ops->unmap(info, buf);
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return ret;
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}
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@@ -519,11 +560,10 @@ typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
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* key here is the 'actor' worker passed in that actually moves the data
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* to the wanted destination. See pipe_to_file/pipe_to_sendpage above.
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*/
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-static ssize_t move_from_pipe(struct inode *inode, 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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splice_actor *actor)
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{
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- struct pipe_inode_info *info;
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int ret, do_wakeup, err;
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struct splice_desc sd;
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@@ -535,22 +575,19 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
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sd.file = out;
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sd.pos = out->f_pos;
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- mutex_lock(PIPE_MUTEX(*inode));
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+ if (pipe->inode)
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+ mutex_lock(&pipe->inode->i_mutex);
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- info = inode->i_pipe;
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for (;;) {
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- int bufs = info->nrbufs;
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-
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- if (bufs) {
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- int curbuf = info->curbuf;
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- struct pipe_buffer *buf = info->bufs + curbuf;
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+ if (pipe->nrbufs) {
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+ struct pipe_buffer *buf = pipe->bufs + pipe->curbuf;
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struct pipe_buf_operations *ops = buf->ops;
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sd.len = buf->len;
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if (sd.len > sd.total_len)
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sd.len = sd.total_len;
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- err = actor(info, buf, &sd);
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+ err = actor(pipe, buf, &sd);
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if (err) {
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if (!ret && err != -ENODATA)
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ret = err;
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@@ -561,13 +598,14 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
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ret += sd.len;
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buf->offset += sd.len;
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buf->len -= sd.len;
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+
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if (!buf->len) {
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buf->ops = NULL;
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- ops->release(info, buf);
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- curbuf = (curbuf + 1) & (PIPE_BUFFERS - 1);
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- info->curbuf = curbuf;
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- info->nrbufs = --bufs;
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- do_wakeup = 1;
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+ ops->release(pipe, buf);
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+ pipe->curbuf = (pipe->curbuf + 1) & (PIPE_BUFFERS - 1);
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+ pipe->nrbufs--;
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+ if (pipe->inode)
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+ do_wakeup = 1;
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}
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sd.pos += sd.len;
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@@ -576,11 +614,11 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
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break;
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}
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- if (bufs)
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+ if (pipe->nrbufs)
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continue;
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- if (!PIPE_WRITERS(*inode))
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+ if (!pipe->writers)
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break;
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- if (!PIPE_WAITING_WRITERS(*inode)) {
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+ if (!pipe->waiting_writers) {
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if (ret)
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break;
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}
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@@ -598,31 +636,34 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
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}
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if (do_wakeup) {
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- wake_up_interruptible_sync(PIPE_WAIT(*inode));
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- kill_fasync(PIPE_FASYNC_WRITERS(*inode),SIGIO,POLL_OUT);
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+ smp_mb();
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+ if (waitqueue_active(&pipe->wait))
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+ wake_up_interruptible_sync(&pipe->wait);
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+ kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
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do_wakeup = 0;
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}
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- pipe_wait(inode);
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+ pipe_wait(pipe);
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}
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- mutex_unlock(PIPE_MUTEX(*inode));
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+ if (pipe->inode)
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+ mutex_unlock(&pipe->inode->i_mutex);
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if (do_wakeup) {
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- wake_up_interruptible(PIPE_WAIT(*inode));
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- kill_fasync(PIPE_FASYNC_WRITERS(*inode), SIGIO, POLL_OUT);
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+ smp_mb();
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+ if (waitqueue_active(&pipe->wait))
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+ wake_up_interruptible(&pipe->wait);
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+ kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
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}
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- mutex_lock(&out->f_mapping->host->i_mutex);
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out->f_pos = sd.pos;
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- mutex_unlock(&out->f_mapping->host->i_mutex);
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return ret;
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}
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/**
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* generic_file_splice_write - splice data from a pipe to a file
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- * @inode: pipe inode
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+ * @pipe: pipe info
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* @out: file to write to
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* @len: number of bytes to splice
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* @flags: splice modifier flags
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@@ -631,14 +672,17 @@ static ssize_t move_from_pipe(struct inode *inode, struct file *out,
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* the given pipe inode to the given file.
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*
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*/
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-ssize_t generic_file_splice_write(struct inode *inode, struct file *out,
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- size_t len, unsigned int flags)
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+ssize_t
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+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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struct address_space *mapping = out->f_mapping;
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- ssize_t ret = move_from_pipe(inode, out, len, flags, pipe_to_file);
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+ 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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- * 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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*/
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if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(mapping->host))
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&& ret > 0) {
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@@ -647,7 +691,7 @@ ssize_t generic_file_splice_write(struct inode *inode, struct file *out,
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mutex_lock(&inode->i_mutex);
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err = generic_osync_inode(mapping->host, mapping,
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- OSYNC_METADATA|OSYNC_DATA);
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+ OSYNC_METADATA|OSYNC_DATA);
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mutex_unlock(&inode->i_mutex);
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if (err)
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@@ -670,10 +714,10 @@ EXPORT_SYMBOL(generic_file_splice_write);
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* is involved.
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*
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*/
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-ssize_t generic_splice_sendpage(struct inode *inode, struct file *out,
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+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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{
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- return move_from_pipe(inode, out, len, flags, pipe_to_sendpage);
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+ return move_from_pipe(pipe, out, len, flags, pipe_to_sendpage);
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}
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EXPORT_SYMBOL(generic_splice_sendpage);
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@@ -681,19 +725,20 @@ EXPORT_SYMBOL(generic_splice_sendpage);
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/*
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* Attempt to initiate a splice from pipe to file.
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*/
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-static long do_splice_from(struct inode *pipe, struct file *out, size_t len,
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- unsigned int flags)
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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 pos;
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int ret;
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- if (!out->f_op || !out->f_op->splice_write)
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+ if (unlikely(!out->f_op || !out->f_op->splice_write))
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return -EINVAL;
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- if (!(out->f_mode & FMODE_WRITE))
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+ if (unlikely(!(out->f_mode & FMODE_WRITE)))
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return -EBADF;
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pos = out->f_pos;
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+
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ret = rw_verify_area(WRITE, out, &pos, len);
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if (unlikely(ret < 0))
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return ret;
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@@ -704,19 +749,20 @@ static long do_splice_from(struct inode *pipe, struct file *out, size_t len,
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/*
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* Attempt to initiate a splice from a file to a pipe.
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*/
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-static long do_splice_to(struct file *in, struct inode *pipe, size_t len,
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- unsigned int flags)
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+static long do_splice_to(struct file *in, struct pipe_inode_info *pipe,
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+ size_t len, unsigned int flags)
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{
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loff_t pos, isize, left;
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int ret;
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- if (!in->f_op || !in->f_op->splice_read)
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+ if (unlikely(!in->f_op || !in->f_op->splice_read))
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return -EINVAL;
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- if (!(in->f_mode & FMODE_READ))
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+ if (unlikely(!(in->f_mode & FMODE_READ)))
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return -EBADF;
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pos = in->f_pos;
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+
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ret = rw_verify_area(READ, in, &pos, len);
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if (unlikely(ret < 0))
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return ret;
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@@ -726,32 +772,168 @@ static long do_splice_to(struct file *in, struct inode *pipe, size_t len,
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return 0;
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left = isize - in->f_pos;
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- if (left < len)
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+ if (unlikely(left < len))
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len = left;
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return in->f_op->splice_read(in, pipe, len, flags);
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}
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+long do_splice_direct(struct file *in, struct file *out, size_t len,
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+ unsigned int flags)
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+{
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+ struct pipe_inode_info *pipe;
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+ long ret, bytes;
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+ umode_t i_mode;
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+ int i;
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+
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+ /*
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+ * We require the input being a regular file, as we don't want to
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+ * randomly drop data for eg socket -> socket splicing. Use the
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+ * piped splicing for that!
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+ */
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+ i_mode = in->f_dentry->d_inode->i_mode;
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+ if (unlikely(!S_ISREG(i_mode) && !S_ISBLK(i_mode)))
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+ return -EINVAL;
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+
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+ /*
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+ * neither in nor out is a pipe, setup an internal pipe attached to
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+ * 'out' and transfer the wanted data from 'in' to 'out' through that
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+ */
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+ pipe = current->splice_pipe;
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+ if (unlikely(!pipe)) {
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+ pipe = alloc_pipe_info(NULL);
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+ if (!pipe)
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+ return -ENOMEM;
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+
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+ /*
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+ * We don't have an immediate reader, but we'll read the stuff
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+ * out of the pipe right after the move_to_pipe(). So set
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+ * PIPE_READERS appropriately.
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+ */
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+ pipe->readers = 1;
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+
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+ current->splice_pipe = pipe;
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+ }
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+
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+ /*
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+ * Do the splice.
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+ */
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+ ret = 0;
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+ bytes = 0;
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+
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+ while (len) {
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+ size_t read_len, max_read_len;
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+
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+ /*
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+ * Do at most PIPE_BUFFERS pages worth of transfer:
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+ */
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+ max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));
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+
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+ ret = do_splice_to(in, pipe, max_read_len, flags);
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+ if (unlikely(ret < 0))
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+ goto out_release;
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+
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+ read_len = ret;
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+
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+ /*
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+ * NOTE: nonblocking mode only applies to the input. We
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+ * must not do the output in nonblocking mode as then we
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+ * could get stuck data in the internal pipe:
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+ */
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+ ret = do_splice_from(pipe, out, read_len,
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+ flags & ~SPLICE_F_NONBLOCK);
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+ if (unlikely(ret < 0))
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+ goto out_release;
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+
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+ bytes += ret;
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+ len -= ret;
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+
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+ /*
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+ * In nonblocking mode, if we got back a short read then
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+ * that was due to either an IO error or due to the
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+ * pagecache entry not being there. In the IO error case
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+ * the _next_ splice attempt will produce a clean IO error
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+ * return value (not a short read), so in both cases it's
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+ * correct to break out of the loop here:
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+ */
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+ if ((flags & SPLICE_F_NONBLOCK) && (read_len < max_read_len))
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+ break;
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+ }
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+
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+ pipe->nrbufs = pipe->curbuf = 0;
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+
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+ return bytes;
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+
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+out_release:
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+ /*
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+ * If we did an incomplete transfer we must release
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+ * the pipe buffers in question:
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+ */
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+ for (i = 0; i < PIPE_BUFFERS; i++) {
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+ struct pipe_buffer *buf = pipe->bufs + i;
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+
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+ if (buf->ops) {
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+ buf->ops->release(pipe, buf);
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+ buf->ops = NULL;
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+ }
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+ }
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+ pipe->nrbufs = pipe->curbuf = 0;
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+
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+ /*
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+ * If we transferred some data, return the number of bytes:
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+ */
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+ if (bytes > 0)
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+ return bytes;
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+
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+ return ret;
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+}
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+
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+EXPORT_SYMBOL(do_splice_direct);
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+
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/*
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* Determine where to splice to/from.
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*/
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-static long do_splice(struct file *in, struct file *out, size_t len,
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- unsigned int flags)
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+static long do_splice(struct file *in, loff_t __user *off_in,
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+ struct file *out, loff_t __user *off_out,
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+ size_t len, unsigned int flags)
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{
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- struct inode *pipe;
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+ struct pipe_inode_info *pipe;
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+
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+ pipe = in->f_dentry->d_inode->i_pipe;
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+ if (pipe) {
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+ if (off_in)
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+ return -ESPIPE;
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+ if (off_out) {
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+ if (out->f_op->llseek == no_llseek)
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+ return -EINVAL;
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+ if (copy_from_user(&out->f_pos, off_out,
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+ sizeof(loff_t)))
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+ return -EFAULT;
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+ }
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- pipe = in->f_dentry->d_inode;
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- if (pipe->i_pipe)
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return do_splice_from(pipe, out, len, flags);
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+ }
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+
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+ pipe = out->f_dentry->d_inode->i_pipe;
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+ if (pipe) {
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+ if (off_out)
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+ return -ESPIPE;
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+ if (off_in) {
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+ if (in->f_op->llseek == no_llseek)
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+ return -EINVAL;
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+ if (copy_from_user(&in->f_pos, off_in, sizeof(loff_t)))
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+ return -EFAULT;
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+ }
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- pipe = out->f_dentry->d_inode;
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- if (pipe->i_pipe)
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return do_splice_to(in, pipe, len, flags);
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+ }
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return -EINVAL;
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}
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-asmlinkage long sys_splice(int fdin, int fdout, size_t len, unsigned int flags)
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+asmlinkage long sys_splice(int fd_in, loff_t __user *off_in,
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+ int fd_out, loff_t __user *off_out,
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+ size_t len, unsigned int flags)
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|
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{
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long error;
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struct file *in, *out;
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@@ -761,13 +943,15 @@ asmlinkage long sys_splice(int fdin, int fdout, size_t len, unsigned int flags)
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return 0;
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error = -EBADF;
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- in = fget_light(fdin, &fput_in);
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+ in = fget_light(fd_in, &fput_in);
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if (in) {
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if (in->f_mode & FMODE_READ) {
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- out = fget_light(fdout, &fput_out);
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+ out = fget_light(fd_out, &fput_out);
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if (out) {
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if (out->f_mode & FMODE_WRITE)
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- error = do_splice(in, out, len, flags);
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+ error = do_splice(in, off_in,
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+ out, off_out,
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+ len, flags);
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|
|
fput_light(out, fput_out);
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}
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}
|