btrfs: use super write guard in relocating_repair_kthread()

Link: https://patch.msgid.link/20251104-work-guards-v1-6-5108ac78a171@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: brauner

fs/btrfs/volumes.c

@@ -8177,12 +8177,12 @@ static int relocating_repair_kthread(void *data)
 	target = cache->start;
 	btrfs_put_block_group(cache);
 
-	sb_start_write(fs_info->sb);
+	guard(super_write)(fs_info->sb);
+
 	if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
 		btrfs_info(fs_info,
 			   "zoned: skip relocating block group %llu to repair: EBUSY",
 			   target);
-		sb_end_write(fs_info->sb);
 		return -EBUSY;
 	}
 
@@ -8210,7 +8210,6 @@ static int relocating_repair_kthread(void *data)
 		btrfs_put_block_group(cache);
 	mutex_unlock(&fs_info->reclaim_bgs_lock);
 	btrfs_exclop_finish(fs_info);
-	sb_end_write(fs_info->sb);
 
 	return ret;
 }