[PATCH 4.19 128/131] dm writecache: correct uncommitted_block when discarding uncommitted entry

[Sasha Levin]

From: Huaisheng Ye <yehs1@xxxxxxxxxx>

commit 39495b12ef1cf602e6abd350dce2ef4199906531 upstream.

When uncommitted entry has been discarded, correct wc->uncommitted_block
for getting the exact number.

Fixes: 48debafe4f2fe ("dm: add writecache target")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Huaisheng Ye <yehs1@xxxxxxxxxx>
Acked-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/md/dm-writecache.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index 4321c48eba6b9..509552fc55fc7 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -811,6 +811,8 @@ static void writecache_discard(struct dm_writecache *wc, sector_t start, sector_
 				writecache_wait_for_ios(wc, WRITE);
 				discarded_something = true;
 			}
+			if (!writecache_entry_is_committed(wc, e))
+				wc->uncommitted_blocks--;
 			writecache_free_entry(wc, e);
 		}
 
-- 
2.25.1