btrfs: dev-replace: replace's scrub must not be running in suspended state

When the replace state is 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>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index c0878ff..a84affa 100644 (file)
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -840,7 +840,9 @@ 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)) {