[PATCH v4 1/2] f2fs: flush SIT journal during filesystem resize

[Wenjie Qi]

During a filesystem resize, SBI_IS_RESIZEFS prevents new SIT entries
from being added to the journal and forces existing entries to the SIT
area. However, f2fs_flush_sit_entries() returns early when there are no
new dirty sentries, leaving existing journal entries behind.

After the main area shrinks, a later checkpoint can access a journal
entry whose segment number is outside the new geometry and trigger
f2fs_bug_on().

Only take the zero-dirty fast path when entries may be written back to
the journal. This lets resize drain existing entries through
remove_sits_in_journal() even when there are no new dirty sentries.

Fixes: 04f0b2eaa3b3 ("f2fs: ioctl for removing a range from F2FS")
Reviewed-by: Daeho Jeong <daehojeong@xxxxxxxxxx>
Signed-off-by: Wenjie Qi <qiwenjie@xxxxxxxxxx>
---
 fs/f2fs/segment.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 25785b7626bb9..bf8d07fcce331 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -4893,7 +4893,7 @@ void f2fs_flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	down_write(&sit_i->sentry_lock);
 
-	if (!sit_i->dirty_sentries)
+	if (!sit_i->dirty_sentries && to_journal)
 		goto out;
 
 	/*
-- 
2.43.0