[PATCH] md/bitmap: resume array on backlog_store() error path

["Chen Cheng" <chencheng@fnnas.com>]

From: Chen Cheng <chencheng@fnnas.com>

backlog_store() suspends the array before checking whether a write-mostly
device exists. If no such device exists, the error path only unlocks
reconfig_mutex and leaves the array suspended, blocking subsequent I/O.

Use mddev_unlock_and_resume() to release both states.

Fixes: 58226942ad3d ("md: use new apis to suspend array before mddev_create/destroy_serial_pool")

Signed-off-by: Chen Cheng <chencheng@fnnas.com>
---
 drivers/md/md-bitmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 028b9ca8ce52..3e40cb45d473 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -2854,11 +2854,11 @@ backlog_store(struct mddev *mddev, const char *buf, size_t len)
 		}
 	}
 	if (!has_write_mostly) {
 		pr_warn_ratelimited("%s: can't set backlog, no write mostly device available\n",
 				    mdname(mddev));
-		mddev_unlock(mddev);
+		mddev_unlock_and_resume(mddev);
 		return -EINVAL;
 	}
 
 	mddev->bitmap_info.max_write_behind = backlog;
 	if (!backlog && mddev->serial_info_pool) {
-- 
2.54.0