nr_pages = PIPE_BUFFERS;
/*
- * Initiate read-ahead on this page range. however, don't call into
- * read-ahead if this is a non-zero offset (we are likely doing small
- * chunk splice and the page is already there) for a single page.
+ * Don't try to 2nd guess the read-ahead logic, call into
+ * page_cache_readahead() like the page cache reads would do.
*/
- if (!loff || nr_pages > 1)
- page_cache_readahead(mapping, &in->f_ra, in, index, nr_pages);
+ page_cache_readahead(mapping, &in->f_ra, in, index, nr_pages);
/*
* Now fill in the holes:
* If in nonblock mode then dont block on waiting
* for an in-flight io page
*/
- if (flags & SPLICE_F_NONBLOCK)
- break;
-
- lock_page(page);
+ if (flags & SPLICE_F_NONBLOCK) {
+ if (TestSetPageLocked(page))
+ break;
+ } else
+ lock_page(page);
/*
* page was truncated, stop here. if this isn't the
if (this_len + offset > PAGE_CACHE_SIZE)
this_len = PAGE_CACHE_SIZE - offset;
- /*
- * Reuse buf page, if SPLICE_F_MOVE is set and we are doing a full
- * page.
- */
- if ((sd->flags & SPLICE_F_MOVE) && this_len == PAGE_CACHE_SIZE) {
- /*
- * If steal succeeds, buf->page is now pruned from the
- * pagecache and we can reuse it. The page will also be
- * locked on successful return.
- */
- if (buf->ops->steal(pipe, buf))
- goto find_page;
-
- page = buf->page;
- if (add_to_page_cache(page, mapping, index, GFP_KERNEL)) {
- unlock_page(page);
- goto find_page;
- }
-
- page_cache_get(page);
-
- if (!(buf->flags & PIPE_BUF_FLAG_LRU))
- lru_cache_add(page);
- } else {
find_page:
- page = find_lock_page(mapping, index);
- if (!page) {
- ret = -ENOMEM;
- page = page_cache_alloc_cold(mapping);
- if (unlikely(!page))
- goto out_ret;
-
- /*
- * This will also lock the page
- */
- ret = add_to_page_cache_lru(page, mapping, index,
- GFP_KERNEL);
- if (unlikely(ret))
- goto out;
- }
+ page = find_lock_page(mapping, index);
+ if (!page) {
+ ret = -ENOMEM;
+ page = page_cache_alloc_cold(mapping);
+ if (unlikely(!page))
+ goto out_ret;
/*
- * We get here with the page locked. If the page is also
- * uptodate, we don't need to do more. If it isn't, we
- * may need to bring it in if we are not going to overwrite
- * the full page.
+ * This will also lock the page
*/
- if (!PageUptodate(page)) {
- if (this_len < PAGE_CACHE_SIZE) {
- ret = mapping->a_ops->readpage(file, page);
- if (unlikely(ret))
- goto out;
-
- lock_page(page);
-
- if (!PageUptodate(page)) {
- /*
- * Page got invalidated, repeat.
- */
- if (!page->mapping) {
- unlock_page(page);
- page_cache_release(page);
- goto find_page;
- }
- ret = -EIO;
- goto out;
- }
- } else
- SetPageUptodate(page);
- }
+ ret = add_to_page_cache_lru(page, mapping, index,
+ GFP_KERNEL);
+ if (unlikely(ret))
+ goto out;
}
ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
}
ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);
- if (!ret) {
+ if (ret) {
+ if (ret == AOP_TRUNCATED_PAGE) {
+ page_cache_release(page);
+ goto find_page;
+ }
+ if (ret < 0)
+ goto out;
/*
- * Return the number of bytes written and mark page as
- * accessed, we are now done!
+ * Partial write has happened, so 'ret' already initialized by
+ * number of bytes written, Where is nothing we have to do here.
*/
+ } else
ret = this_len;
- mark_page_accessed(page);
- balance_dirty_pages_ratelimited(mapping);
- } else if (ret == AOP_TRUNCATED_PAGE) {
- page_cache_release(page);
- goto find_page;
- }
+ /*
+ * Return the number of bytes written and mark page as
+ * accessed, we are now done!
+ */
+ mark_page_accessed(page);
+ balance_dirty_pages_ratelimited(mapping);
out:
page_cache_release(page);
unlock_page(page);
* key here is the 'actor' worker passed in that actually moves the data
* to the wanted destination. See pipe_to_file/pipe_to_sendpage above.
*/
-static ssize_t __splice_from_pipe(struct pipe_inode_info *pipe,
- struct file *out, loff_t *ppos, size_t len,
- unsigned int flags, splice_actor *actor)
+ssize_t __splice_from_pipe(struct pipe_inode_info *pipe,
+ struct file *out, loff_t *ppos, size_t len,
+ unsigned int flags, splice_actor *actor)
{
int ret, do_wakeup, err;
struct splice_desc sd;
return ret;
}
+EXPORT_SYMBOL(__splice_from_pipe);
ssize_t splice_from_pipe(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags,
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