typedef void (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *,
bool);
typedef void (busy_tag_iter_fn)(struct request *, void *, bool);
typedef void (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *,
bool);
typedef void (busy_tag_iter_fn)(struct request *, void *, bool);