[PATCH] splice: Convert page_cache_pipe_buf_confirm() to use a folio

[PATCH] splice: Convert page_cache_pipe_buf_confirm() to use a folio

[Matthew Wilcox (Oracle)]

Convert buf->page to a folio once instead of five times.  There's only
one uptodate bit per folio, not per page, so we lose nothing here.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 fs/splice.c | 20 +++++++++-----------
 1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index 5c7c8c636b2c..d983d375ff11 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -119,17 +119,17 @@ static void page_cache_pipe_buf_release(struct pipe_inode_info *pipe,
 static int page_cache_pipe_buf_confirm(struct pipe_inode_info *pipe,
 				       struct pipe_buffer *buf)
 {
-	struct page *page = buf->page;
+	struct folio *folio = page_folio(buf->page);
 	int err;
 
-	if (!PageUptodate(page)) {
-		lock_page(page);
+	if (!folio_test_uptodate(folio)) {
+		folio_lock(folio);
 
 		/*
-		 * Page got truncated/unhashed. This will cause a 0-byte
+		 * Folio got truncated/unhashed. This will cause a 0-byte
 		 * splice, if this is the first page.
 		 */
-		if (!page->mapping) {
+		if (!folio->mapping) {
 			err = -ENODATA;
 			goto error;
 		}
@@ -137,20 +137,18 @@ static int page_cache_pipe_buf_confirm(struct pipe_inode_info *pipe,
 		/*
 		 * Uh oh, read-error from disk.
 		 */
-		if (!PageUptodate(page)) {
+		if (!folio_test_uptodate(folio)) {
 			err = -EIO;
 			goto error;
 		}
 
-		/*
-		 * Page is ok afterall, we are done.
-		 */
-		unlock_page(page);
+		/* Folio is ok after all, we are done */
+		folio_unlock(folio);
 	}
 
 	return 0;
 error:
-	unlock_page(page);
+	folio_unlock(folio);
 	return err;
 }
 
-- 
2.40.1

Re: [PATCH] splice: Convert page_cache_pipe_buf_confirm() to use a folio

[Christian Brauner]

On Mon, 21 Aug 2023 15:15:41 +0100, Matthew Wilcox (Oracle) wrote:
> Convert buf->page to a folio once instead of five times.  There's only
> one uptodate bit per folio, not per page, so we lose nothing here.
> 
> 

Applied to the vfs.misc branch of the vfs/vfs.git tree.
Patches in the vfs.misc branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.misc

[1/1] splice: Convert page_cache_pipe_buf_confirm() to use a folio
      https://git.kernel.org/vfs/vfs/c/4e1428925b4b