[PATCH] Remove queue merging hooks

We have full flexibility of merging parameters now, so we can remove the
hooks that define back/front/request merge strategies. Nobody is using
them anymore.

Signed-off-by: Jens Axboe <[e-mail]>

block/ll_rw_blk.c

···
 	return 1;
 }
 
-static int ll_back_merge_fn(request_queue_t *q, struct request *req, 
-			    struct bio *bio)
+int ll_back_merge_fn(request_queue_t *q, struct request *req, struct bio *bio)
 {
 	unsigned short max_sectors;
 	int len;
···
 
 	return ll_new_hw_segment(q, req, bio);
 }
+EXPORT_SYMBOL(ll_back_merge_fn);
 
 static int ll_front_merge_fn(request_queue_t *q, struct request *req, 
 			     struct bio *bio)
···
 	}
 
 	q->request_fn		= rfn;
-	q->back_merge_fn       	= ll_back_merge_fn;
-	q->front_merge_fn      	= ll_front_merge_fn;
-	q->merge_requests_fn	= ll_merge_requests_fn;
 	q->prep_rq_fn		= NULL;
 	q->unplug_fn		= generic_unplug_device;
 	q->queue_flags		= (1 << QUEUE_FLAG_CLUSTER);
···
 	spin_lock_irq(q->queue_lock);
 	if (!rq->bio)
 		blk_rq_bio_prep(q, rq, bio);
-	else if (!q->back_merge_fn(q, rq, bio)) {
+	else if (!ll_back_merge_fn(q, rq, bio)) {
 		ret = -EINVAL;
 		spin_unlock_irq(q->queue_lock);
 		goto unmap_bio;
···
 	 * will have updated segment counts, update sector
 	 * counts here.
 	 */
-	if (!q->merge_requests_fn(q, req, next))
+	if (!ll_merge_requests_fn(q, req, next))
 		return 0;
 
 	/*
···
 		case ELEVATOR_BACK_MERGE:
 			BUG_ON(!rq_mergeable(req));
 
-			if (!q->back_merge_fn(q, req, bio))
+			if (!ll_back_merge_fn(q, req, bio))
 				break;
 
 			blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE);
···
 		case ELEVATOR_FRONT_MERGE:
 			BUG_ON(!rq_mergeable(req));
 
-			if (!q->front_merge_fn(q, req, bio))
+			if (!ll_front_merge_fn(q, req, bio))
 				break;
 
 			blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE);

drivers/scsi/scsi_lib.c

···
 
 	if (!rq->bio)
 		blk_rq_bio_prep(q, rq, bio);
-	else if (!q->back_merge_fn(q, rq, bio))
+	else if (!ll_back_merge_fn(q, rq, bio))
 		return -EINVAL;
 	else {
 		rq->biotail->bi_next = bio;

include/linux/blkdev.h

···
 
 #include <linux/elevator.h>
 
-typedef int (merge_request_fn) (request_queue_t *, struct request *,
-				struct bio *);
-typedef int (merge_requests_fn) (request_queue_t *, struct request *,
-				 struct request *);
 typedef void (request_fn_proc) (request_queue_t *q);
 typedef int (make_request_fn) (request_queue_t *q, struct bio *bio);
 typedef int (prep_rq_fn) (request_queue_t *, struct request *);
···
 	struct request_list	rq;
 
 	request_fn_proc		*request_fn;
-	merge_request_fn	*back_merge_fn;
-	merge_request_fn	*front_merge_fn;
-	merge_requests_fn	*merge_requests_fn;
 	make_request_fn		*make_request_fn;
 	prep_rq_fn		*prep_rq_fn;
 	unplug_fn		*unplug_fn;
···
 extern int scsi_cmd_ioctl(struct file *, struct gendisk *, unsigned int, void __user *);
 extern int sg_scsi_ioctl(struct file *, struct request_queue *,
 		struct gendisk *, struct scsi_ioctl_command __user *);
+
+/*
+ * Temporary export, until SCSI gets fixed up.
+ */
+extern int ll_back_merge_fn(request_queue_t *, struct request *, struct bio *);
 
 /*
  * A queue has just exitted congestion.  Note this in the global counter of