return fmt.Errorf("ID %v is already in use", id)
	}
	oid, ok := testQuotaIDMap[dir]
	if ok && id != oid {
		return fmt.Errorf("directory %s already has a quota applied", dir)
	}
	testQuotaIDMap[dir] = id
	testIDQuotaMap[id] = dir
	return nil
}

func (v testVolumeQuota) GetQuotaOnDir(path string) (common.QuotaID, error) {
	id, ok := testQuotaIDMap[path]
	if ok {
		return id, nil
	}