[PATCH 16/19] writeback: Remove a use of write_cache_pages() from do_writepages()

From: Christoph Hellwig
Date: Thu Jan 25 2024 - 04:04:26 EST


From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>

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

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Acked-by: Dave Chinner <dchinner@xxxxxxxxxx>
---
mm/page-writeback.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index aca0f43021a20c..81034d5d72e1f4 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2559,13 +2559,21 @@ 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)
@@ -2581,12 +2589,7 @@ 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;
--
2.39.2