sunvdc: use blk_mq_alloc_disk

Use the blk_mq_alloc_disk API to simplify the gendisk and request_queue
allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210602065345.355274-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/sunvdc.c

@@ -780,27 +780,6 @@ static const struct blk_mq_ops vdc_mq_ops = {
 	.queue_rq	= vdc_queue_rq,
 };
 
-static void cleanup_queue(struct request_queue *q)
-{
-	struct vdc_port *port = q->queuedata;
-
-	blk_cleanup_queue(q);
-	blk_mq_free_tag_set(&port->tag_set);
-}
-
-static struct request_queue *init_queue(struct vdc_port *port)
-{
-	struct request_queue *q;
-
-	q = blk_mq_init_sq_queue(&port->tag_set, &vdc_mq_ops, VDC_TX_RING_SIZE,
-					BLK_MQ_F_SHOULD_MERGE);
-	if (IS_ERR(q))
-		return q;
-
-	q->queuedata = port;
-	return q;
-}
-
 static int probe_disk(struct vdc_port *port)
 {
 	struct request_queue *q;
@@ -838,21 +817,21 @@ static int probe_disk(struct vdc_port *port)
 				    (u64)geom.num_sec);
 	}
 
-	q = init_queue(port);
-	if (IS_ERR(q)) {
-		printk(KERN_ERR PFX "%s: Could not allocate queue.\n",
-		       port->vio.name);
-		return PTR_ERR(q);
-	}
-	g = alloc_disk(1 << PARTITION_SHIFT);
-	if (!g) {
+	err = blk_mq_alloc_sq_tag_set(&port->tag_set, &vdc_mq_ops,
+			VDC_TX_RING_SIZE, BLK_MQ_F_SHOULD_MERGE);
+	if (err)
+		return err;
+
+	g = blk_mq_alloc_disk(&port->tag_set, port);
+	if (IS_ERR(g)) {
 		printk(KERN_ERR PFX "%s: Could not allocate gendisk.\n",
 		       port->vio.name);
-		cleanup_queue(q);
-		return -ENOMEM;
+		blk_mq_free_tag_set(&port->tag_set);
+		return PTR_ERR(g);
 	}
 
 	port->disk = g;
+	q = g->queue;
 
 	/* Each segment in a request is up to an aligned page in size. */
 	blk_queue_segment_boundary(q, PAGE_SIZE - 1);
@@ -862,6 +841,7 @@ static int probe_disk(struct vdc_port *port)
 	blk_queue_max_hw_sectors(q, port->max_xfer_size);
 	g->major = vdc_major;
 	g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;
+	g->minors = 1 << PARTITION_SHIFT;
 	strcpy(g->disk_name, port->disk_name);
 
 	g->fops = &vdc_fops;
@@ -1083,9 +1063,8 @@ static int vdc_port_remove(struct vio_dev *vdev)
 		del_timer_sync(&port->vio.timer);
 
 		del_gendisk(port->disk);
-		cleanup_queue(port->disk->queue);
-		put_disk(port->disk);
-		port->disk = NULL;
+		blk_cleanup_disk(port->disk);
+		blk_mq_free_tag_set(&port->tag_set);
 
 		vdc_free_tx_ring(port);
 		vio_ldc_free(&port->vio);