[PATCH 6.16 2/9] ext4: move the calculation of wbc->nr_to_write to mpage_folio_done()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.16-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Zhang Yi <yi.zhang@huawei.com>

commit f922c8c2461b022a2efd9914484901fb358a5b2a upstream.

mpage_folio_done() should be a more appropriate place than
mpage_submit_folio() for updating the wbc->nr_to_write after we have
submitted a fully mapped folio. Preparing to make mpage_submit_folio()
allows to submit partially mapped folio that is still under processing.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Link: https://patch.msgid.link/20250707140814.542883-3-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/ext4/inode.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2027,6 +2027,7 @@ int ext4_da_get_block_prep(struct inode
 static void mpage_folio_done(struct mpage_da_data *mpd, struct folio *folio)
 {
 	mpd->start_pos += folio_size(folio);
+	mpd->wbc->nr_to_write -= folio_nr_pages(folio);
 	folio_unlock(folio);
 }
 
@@ -2057,8 +2058,6 @@ static int mpage_submit_folio(struct mpa
 	    !ext4_verity_in_progress(mpd->inode))
 		len = size & (len - 1);
 	err = ext4_bio_write_folio(&mpd->io_submit, folio, len);
-	if (!err)
-		mpd->wbc->nr_to_write -= folio_nr_pages(folio);
 
 	return err;
 }