'Prepares list of eligible files to be deleted from cache.'

def _shortlist_del_eligible_files(self, share, old_files):

    file_list = []
    (_, export_path) = self._get_export_ip_path(share=share)
    exported_volume = self.zapi_client.get_actual_path_for_export(export_path)
    for old_file in old_files:
        path = os.path.join(exported_volume, old_file)
        u_bytes = self.zapi_client.get_file_usage(path)
        file_list.append((old_file, u_bytes))
    LOG.debug('Shortlisted    files    eligible    for    deletion:    %s', file_list)
    return file_list
