diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 8b851ac..6f364e1 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -4219,7 +4219,8 @@
 static inline int is_fstree(u64 rootid)
 {
 	if (rootid == BTRFS_FS_TREE_OBJECTID ||
-	    (s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID)
+	    ((s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID &&
+	      !btrfs_qgroup_level(rootid)))
 		return 1;
 	return 0;
 }
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 2e66d8e..e38b645 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -456,6 +456,13 @@
 	if (ret)
 		return ret;
 
+	/*
+	 * Don't create subvolume whose level is not zero. Or qgroup will be
+	 * screwed up since it assume subvolme qgroup's level to be 0.
+	 */
+	if (btrfs_qgroup_level(objectid))
+		return -ENOSPC;
+
 	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 	/*
 	 * The same as the snapshot creation, please see the comment