These FIXMEs were already addressed in 2013. All functions check for
qgroup existence:
* btrfs_add_qgroup_relation
* btrfs_ioctl_qgroup_create
* btrfs_limit_qgroup
* btrfs_del_qgroup_relation
Signed-off-by: Daichou <tommy0705c@gmail.com>
[ enhance and reformat changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
                goto out;
        }
 
-       /* FIXME: check if the IDs really exist */
        if (sa->assign) {
                ret = btrfs_add_qgroup_relation(trans, fs_info,
                                                sa->src, sa->dst);
                goto out;
        }
 
-       /* FIXME: check if the IDs really exist */
        if (sa->create) {
                ret = btrfs_create_qgroup(trans, fs_info, sa->qgroupid);
        } else {
                qgroupid = root->root_key.objectid;
        }
 
-       /* FIXME: check if the IDs really exist */
        ret = btrfs_limit_qgroup(trans, fs_info, qgroupid, &sa->lim);
 
        err = btrfs_end_transaction(trans);