MD_FEATURE_QUERY_ID
ft_query->head_pattern = cpu_to_le32(MD_FEATURE_QUERY_ID);
ft_query->tail_pattern = cpu_to_le32(MD_FEATURE_QUERY_ID);
if (le32_to_cpu(md_feature->head_pattern) != MD_FEATURE_QUERY_ID ||
le32_to_cpu(md_feature->tail_pattern) != MD_FEATURE_QUERY_ID) {