[PATCH 6.1 0660/1146] f2fs: avoid victim selection from previous victim section

Greg Kroah-Hartman
2022-12-28T16:19:40Z

From: Yonggil Song <yonggil.song@samsung.com>

[ Upstream commit e219aecfd4b766c4e878a3769057e9809f7fcadc ]

When f2fs chooses GC victim in large section & LFS mode,
next_victim_seg[gc_type] is referenced first. After segment is freed,
next_victim_seg[gc_type] has the next segment number.
However, next_victim_seg[gc_type] still has the last segment number
even after the last segment of section is freed. In this case, when f2fs
chooses a victim for the next GC round, the last segment of previous victim
section is chosen as a victim.

Initialize next_victim_seg[gc_type] to NULL_SEGNO for the last segment in
large section.

Fixes: e3080b0120a1 ("f2fs: support subsectional garbage collection")
Signed-off-by: Yonggil Song <yonggil.song@samsung.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/f2fs/gc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index f46e4dcaa252..22c1f876e8c5 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1743,8 +1743,9 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
get_valid_blocks(sbi, segno, false) == 0)
seg_freed++;

- if (__is_large_section(sbi) && segno + 1 < end_segno)
- sbi->next_victim_seg[gc_type] = segno + 1;
+ if (__is_large_section(sbi))
+ sbi->next_victim_seg[gc_type] =
+ (segno + 1 < end_segno) ? segno + 1 : NULL_SEGNO;
skip:
f2fs_put_page(sum_page, 0);
}
--
2.35.1