[PATCH v2 2/2] ocfs2: fix the space leak in LA when releasing LA

[Heming Zhao <heming.zhao@suse.com>]

Commit 30dd3478c3cd ("ocfs2: correctly use ocfs2_find_next_zero_bit()")
introduced an issue, the ocfs2_sync_local_to_main() ignores the last
contiguous free bits, which causes an OCFS2 volume to lose the last free
clusters of LA window during the release routine.

Please note, because commit dfe6c5692fb5 ("ocfs2: fix the la space leak
when unmounting an ocfs2 volume") was reverted, this commit is a
replacement fix for commit dfe6c5692fb5.

Fixes: 30dd3478c3cd ("ocfs2: correctly use ocfs2_find_next_zero_bit()")
Signed-off-by: Heming Zhao <heming.zhao@suse.com>
Suggested-by: Joseph Qi <joseph.qi@linux.alibaba.com>
---
 fs/ocfs2/localalloc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c
index 5df34561c551..d1aa04a5af1b 100644
--- a/fs/ocfs2/localalloc.c
+++ b/fs/ocfs2/localalloc.c
@@ -971,9 +971,9 @@ static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
 	start = count = 0;
 	left = le32_to_cpu(alloc->id1.bitmap1.i_total);
 
-	while ((bit_off = ocfs2_find_next_zero_bit(bitmap, left, start)) <
-	       left) {
-		if (bit_off == start) {
+	while (1) {
+		bit_off = ocfs2_find_next_zero_bit(bitmap, left, start);
+		if ((bit_off < left) && (bit_off == start)) {
 			count++;
 			start++;
 			continue;
@@ -998,6 +998,8 @@ static int ocfs2_sync_local_to_main(struct ocfs2_super *osb,
 			}
 		}
 
+		if (bit_off >= left)
+			break;
 		count = 1;
 		start = bit_off + 1;
 	}
-- 
2.43.0