[PATCH v2 13/14] netfs: Fix folio state after ENOMEM whilst under writeback iteration

[David Howells <dhowells@redhat.com>]

Fix the state of the current folio when ENOMEM occurs during writeback
iteration.  The folio needs to be redirtied and unlocked before the
terminal writeback_iter() is invoked.

Fixes: 06fa229ceb36 ("netfs: Abstract out a rolling folio buffer implementation")
Link: https://sashiko.dev/#/patchset/20260619140646.2633762-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Matthew Wilcox <willy@infradead.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
---
 fs/netfs/write_issue.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/netfs/write_issue.c b/fs/netfs/write_issue.c
index d1f98cca5d0f..6eb6cff12c17 100644
--- a/fs/netfs/write_issue.c
+++ b/fs/netfs/write_issue.c
@@ -334,8 +334,11 @@ static int netfs_write_folio(struct netfs_io_request *wreq,
 
 	_enter("");
 
-	if (rolling_buffer_make_space(&wreq->buffer) < 0)
+	if (rolling_buffer_make_space(&wreq->buffer) < 0) {
+		folio_redirty_for_writepage(wbc, folio);
+		folio_unlock(folio);
 		return -ENOMEM;
+	}
 
 	/* netfs_perform_write() may shift i_size around the page or from out
 	 * of the page to beyond it, but cannot move i_size into or through the