[PATCH 6/9] btrfs: replace's scrub must not be running in replace suspended state

[Anand Jain <anand.jain@oracle.com>]

When the replace state is placed in the suspended state,
btrfs_scrub_cancel() should fail with -ENOTCONN as there is no
scrub running, as a safety catch check if btrfs_scrub_cancel()
returns -ENOTCONN and assert if it doesn't.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
 fs/btrfs/dev-replace.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 9fc3cb8d3918..1dc8e86546db 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -831,7 +831,9 @@ int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
 
 		btrfs_dev_replace_write_unlock(dev_replace);
 
-		btrfs_scrub_cancel(fs_info);
+		/* scrub for replace must not be running in suspended state */
+		ret = btrfs_scrub_cancel(fs_info);
+		ASSERT(ret != -ENOTCONN);
 
 		trans = btrfs_start_transaction(root, 0);
 		if (IS_ERR(trans)) {
-- 
1.8.3.1