block: remove q->lld_busy_fn()

Nobody is using the legacy path for blk_lld_busy() anymore, remove
it.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-core.c

@@ -3429,8 +3429,6 @@ EXPORT_SYMBOL_GPL(rq_flush_dcache_pages);
  */
 int blk_lld_busy(struct request_queue *q)
 {
-	if (q->lld_busy_fn)
-		return q->lld_busy_fn(q);
 	if (q->mq_ops && q->mq_ops->busy)
 		return q->mq_ops->busy(q);
 

block/blk-settings.c

@@ -73,12 +73,6 @@ void blk_queue_rq_timed_out(struct request_queue *q, rq_timed_out_fn *fn)
 }
 EXPORT_SYMBOL_GPL(blk_queue_rq_timed_out);
 
-void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn)
-{
-	q->lld_busy_fn = fn;
-}
-EXPORT_SYMBOL_GPL(blk_queue_lld_busy);
-
 /**
  * blk_set_default_limits - reset limits to default values
  * @lim:  the queue_limits structure to reset

include/linux/blkdev.h

@@ -320,7 +320,6 @@ typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
 struct bio_vec;
 typedef void (softirq_done_fn)(struct request *);
 typedef int (dma_drain_needed_fn)(struct request *);
-typedef int (lld_busy_fn) (struct request_queue *q);
 typedef int (bsg_job_fn) (struct bsg_job *);
 typedef int (init_rq_fn)(struct request_queue *, struct request *, gfp_t);
 typedef void (exit_rq_fn)(struct request_queue *, struct request *);
@@ -466,7 +465,6 @@ struct request_queue {
 	softirq_done_fn		*softirq_done_fn;
 	rq_timed_out_fn		*rq_timed_out_fn;
 	dma_drain_needed_fn	*dma_drain_needed;
-	lld_busy_fn		*lld_busy_fn;
 	/* Called just after a request is allocated */
 	init_rq_fn		*init_rq_fn;
 	/* Called just before a request is freed */
@@ -1255,7 +1253,6 @@ extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
 extern int blk_queue_dma_drain(struct request_queue *q,
 			       dma_drain_needed_fn *dma_drain_needed,
 			       void *buf, unsigned int size);
-extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);