+
+bool bio_attempt_front_merge(struct request_queue *q, struct request *req,
+ struct bio *bio);
+bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
+ struct bio *bio);
+bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
+ unsigned int *request_count);
+
+void blk_account_io_start(struct request *req, bool new_io);
+void blk_account_io_completion(struct request *req, unsigned int bytes);
+void blk_account_io_done(struct request *req);
+