[PATCH] f2fs: fix to set .discard_granularity correctly

[Chao Yu]

commit 4f993264fe29 ("f2fs: introduce discard_unit mount option") introduced
a bug, when we enable discard_unit=section option, it will set
.discard_granularity to BLKS_PER_SEC(), however discard granularity only
supports [1, 512], once section size is not equal to segment size, it will
cause issue_discard_thread() in DPOLICY_BG mode will not select discard entry
w/ any granularity to issue.

Fixes: 4f993264fe29 ("f2fs: introduce discard_unit mount option")
Reviewed-by: Daeho Jeong <daehojeong@xxxxxxxxxx>
Signed-off-by: Yohan Joung <yohan.joung@xxxxxx>
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
 fs/f2fs/segment.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 6ebe25eafafa..2b415926641f 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2320,10 +2320,9 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
 	dcc->discard_granularity = DEFAULT_DISCARD_GRANULARITY;
 	dcc->max_ordered_discard = DEFAULT_MAX_ORDERED_DISCARD_GRANULARITY;
 	dcc->discard_io_aware = DPOLICY_IO_AWARE_ENABLE;
-	if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SEGMENT)
+	if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SEGMENT ||
+		F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION)
 		dcc->discard_granularity = BLKS_PER_SEG(sbi);
-	else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION)
-		dcc->discard_granularity = BLKS_PER_SEC(sbi);
 
 	INIT_LIST_HEAD(&dcc->entry_list);
 	for (i = 0; i < MAX_PLIST_NUM; i++)
-- 
2.48.1.601.g30ceb7b040-goog