From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Fri, 14 Mar 2025 04:33:29 +0000 (-0400)
Subject: mpage: Use writeback_iter() instead of write_cache_pages()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fwritepage;p=users%2Fwilly%2Fpagecache.git

mpage: Use writeback_iter() instead of write_cache_pages()

Using the iterator directly adds a little type safety, converts
an indirect call into a direct call and may allow the compiler
to inline __mpage_writepage() into mpage_writepages().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---

diff --git a/fs/mpage.c b/fs/mpage.c
index ad7844de87c30..0f138b2dfae36 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -445,12 +445,11 @@ static void clean_buffers(struct folio *folio, unsigned first_unmapped)
 		try_to_free_buffers(folio);
 }
 
-static int __mpage_writepage(struct folio *folio, struct writeback_control *wbc,
-		      void *data)
+static int __mpage_writepage(struct address_space *mapping,
+		struct writeback_control *wbc, struct folio *folio,
+		struct mpage_data *mpd)
 {
-	struct mpage_data *mpd = data;
 	struct bio *bio = mpd->bio;
-	struct address_space *mapping = folio->mapping;
 	struct inode *inode = mapping->host;
 	const unsigned blkbits = inode->i_blkbits;
 	const unsigned blocks_per_folio = folio_size(folio) >> blkbits;
@@ -649,21 +648,22 @@ out:
  * This is a library function, which implements the writepages()
  * address_space_operation.
  */
-int
-mpage_writepages(struct address_space *mapping,
+int mpage_writepages(struct address_space *mapping,
 		struct writeback_control *wbc, get_block_t get_block)
 {
 	struct mpage_data mpd = {
 		.get_block	= get_block,
 	};
 	struct blk_plug plug;
-	int ret;
+	struct folio *folio = NULL;
+	int err;
 
 	blk_start_plug(&plug);
-	ret = write_cache_pages(mapping, wbc, __mpage_writepage, &mpd);
+	while ((folio = writeback_iter(mapping, wbc, folio, &err)))
+		err = __mpage_writepage(mapping, wbc, folio, &mpd);
 	if (mpd.bio)
 		mpage_bio_submit_write(mpd.bio);
 	blk_finish_plug(&plug);
-	return ret;
+	return err;
 }
 EXPORT_SYMBOL(mpage_writepages);