1 files changed, 12 insertions, 1 deletions

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 28f2b39f6a25..a5c856234323 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -963,17 +963,28 @@ int btrfs_remove_qgroup(struct btrfs_trans_handle *trans,
                         struct btrfs_fs_info *fs_info, u64 qgroupid)
 {
         struct btrfs_root *quota_root;
+        struct btrfs_qgroup *qgroup;
         int ret = 0;
 
         quota_root = fs_info->quota_root;
         if (!quota_root)
                 return -EINVAL;
 
+        /* check if there are no relations to this qgroup */
+        spin_lock(&fs_info->qgroup_lock);
+        qgroup = find_qgroup_rb(fs_info, qgroupid);
+        if (qgroup) {
+                if (!list_empty(&qgroup->groups) || !list_empty(&qgroup->members)) {
+                        spin_unlock(&fs_info->qgroup_lock);
+                        return -EBUSY;
+                }
+        }
+        spin_unlock(&fs_info->qgroup_lock);
+
         ret = del_qgroup_item(trans, quota_root, qgroupid);
 
         spin_lock(&fs_info->qgroup_lock);
         del_qgroup_rb(quota_root->fs_info, qgroupid);
-
         spin_unlock(&fs_info->qgroup_lock);
 
         return ret;