From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Mon, 26 Jun 2023 17:18:13 +0000 (-0400)
Subject: writeback: Remove a use of write_cache_pages() from do_writepages()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=refs%2Fheads%2Fwriteback-iter;p=users%2Fwilly%2Fpagecache.git

writeback: Remove a use of write_cache_pages() from do_writepages()

Use the new for_each_writeback_folio() directly instead of indirecting
through a callback.

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

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 7ee4deb3eef0f..72bf0db7e0b75 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2558,13 +2558,21 @@ int write_cache_pages(struct address_space *mapping,
 }
 EXPORT_SYMBOL(write_cache_pages);
 
-static int writepage_cb(struct folio *folio, struct writeback_control *wbc,
-		void *data)
+static int writeback_use_writepage(struct address_space *mapping,
+		struct writeback_control *wbc)
 {
-	struct address_space *mapping = data;
-	int ret = mapping->a_ops->writepage(&folio->page, wbc);
-	mapping_set_error(mapping, ret);
-	return ret;
+	struct blk_plug plug;
+	struct folio *folio;
+	int err;
+
+	blk_start_plug(&plug);
+	for_each_writeback_folio(mapping, wbc, folio, err) {
+		err = mapping->a_ops->writepage(&folio->page, wbc);
+		mapping_set_error(mapping, err);
+	}
+	blk_finish_plug(&plug);
+
+	return err;
 }
 
 int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
@@ -2580,12 +2588,7 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
 		if (mapping->a_ops->writepages) {
 			ret = mapping->a_ops->writepages(mapping, wbc);
 		} else if (mapping->a_ops->writepage) {
-			struct blk_plug plug;
-
-			blk_start_plug(&plug);
-			ret = write_cache_pages(mapping, wbc, writepage_cb,
-						mapping);
-			blk_finish_plug(&plug);
+			ret = writeback_use_writepage(mapping, wbc);
 		} else {
 			/* deal with chardevs and other special files */
 			ret = 0;