[PATCH 6.18 1019/1611] netfs: Fix folio state after ENOMEM whilst under writeback iteration

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

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

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

From: David Howells <dhowells@redhat.com>

[ Upstream commit b6a713fd34b9498ee2164d5d3e8460732a392efc ]

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>
Link: https://patch.msgid.link/20260625140640.3116900-15-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
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/netfs/write_issue.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/netfs/write_issue.c b/fs/netfs/write_issue.c
index 08bcdd0a871246..76614339554ea0 100644
--- a/fs/netfs/write_issue.c
+++ b/fs/netfs/write_issue.c
@@ -587,6 +587,10 @@ int netfs_writepages(struct address_space *mapping,
 		}
 
 		error = netfs_write_folio(wreq, wbc, folio);
+		if (error == -ENOMEM) {
+			folio_redirty_for_writepage(wbc, folio);
+			folio_unlock(folio);
+		}
 	} while ((folio = writeback_iter(mapping, wbc, folio, &error)));
 
 	netfs_end_issue_write(wreq);
-- 
2.53.0