extern void elv_merged_request(request_queue_t *, struct request *);
extern void elv_remove_request(request_queue_t *, struct request *);
extern void elv_requeue_request(request_queue_t *, struct request *);
extern void elv_merged_request(request_queue_t *, struct request *);
extern void elv_remove_request(request_queue_t *, struct request *);
extern void elv_requeue_request(request_queue_t *, struct request *);