[PATCH 08/11] netfs: Fix group handling in netfs_read_gaps()

[David Howells <dhowells@redhat.com>]

Fix netfs_read_gaps() to not discard the group information from the
netfs_folio struct after successfully reading the gaps.  This is still
needed to write back the dirty data.

Fixes: d259cfb7dd32 ("netfs: Fix read-gaps to remove netfs_folio from filled folio")
Closes: https://sashiko.dev/#/patchset/20260414082004.3756080-1-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/buffered_read.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/netfs/buffered_read.c b/fs/netfs/buffered_read.c
index b4d271538f75..98bfec0af0e1 100644
--- a/fs/netfs/buffered_read.c
+++ b/fs/netfs/buffered_read.c
@@ -461,8 +461,10 @@ static int netfs_read_gaps(struct file *file, struct folio *folio)
 
 	ret = netfs_wait_for_read(rreq);
 	if (ret >= 0) {
-		folio_detach_private(folio);
-		netfs_put_group(group);
+		if (group)
+			folio_change_private(folio, group);
+		else
+			folio_detach_private(folio);
 		kfree(finfo);
 		trace_netfs_folio(folio, netfs_folio_trace_filled_gaps);
 		flush_dcache_folio(folio);