swim: 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/20210602065345.355274-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/swim.c

@@ -800,23 +800,20 @@ static int swim_floppy_init(struct swim_priv *swd)
 	spin_lock_init(&swd->lock);
 
 	for (drive = 0; drive < swd->floppy_count; drive++) {
-		struct request_queue *q;
-
-		swd->unit[drive].disk = alloc_disk(1);
-		if (swd->unit[drive].disk == NULL) {
-			err = -ENOMEM;
+		err = blk_mq_alloc_sq_tag_set(&swd->unit[drive].tag_set,
+				&swim_mq_ops, 2, BLK_MQ_F_SHOULD_MERGE);
+		if (err)
 			goto exit_put_disks;
-		}
 
-		q = blk_mq_init_sq_queue(&swd->unit[drive].tag_set, &swim_mq_ops,
-						2, BLK_MQ_F_SHOULD_MERGE);
-		if (IS_ERR(q)) {
-			err = PTR_ERR(q);
+		swd->unit[drive].disk =
+			blk_mq_alloc_disk(&swd->unit[drive].tag_set,
+					  &swd->unit[drive]);
+		if (IS_ERR(swd->unit[drive].disk)) {
+			blk_mq_free_tag_set(&swd->unit[drive].tag_set);
+			err = PTR_ERR(swd->unit[drive].disk);
 			goto exit_put_disks;
 		}
 
-		swd->unit[drive].disk->queue = q;
-		swd->unit[drive].disk->queue->queuedata = &swd->unit[drive];
 		swd->unit[drive].swd = swd;
 	}
 
@@ -824,6 +821,7 @@ static int swim_floppy_init(struct swim_priv *swd)
 		swd->unit[drive].disk->flags = GENHD_FL_REMOVABLE;
 		swd->unit[drive].disk->major = FLOPPY_MAJOR;
 		swd->unit[drive].disk->first_minor = drive;
+		swd->unit[drive].disk->minors = 1;
 		sprintf(swd->unit[drive].disk->disk_name, "fd%d", drive);
 		swd->unit[drive].disk->fops = &floppy_fops;
 		swd->unit[drive].disk->events = DISK_EVENT_MEDIA_CHANGE;
@@ -839,14 +837,10 @@ static int swim_floppy_init(struct swim_priv *swd)
 	do {
 		struct gendisk *disk = swd->unit[drive].disk;
 
-		if (disk) {
-			if (disk->queue) {
-				blk_cleanup_queue(disk->queue);
-				disk->queue = NULL;
-			}
-			blk_mq_free_tag_set(&swd->unit[drive].tag_set);
-			put_disk(disk);
-		}
+		if (!disk)
+			continue;
+		blk_cleanup_disk(disk);
+		blk_mq_free_tag_set(&swd->unit[drive].tag_set);
 	} while (drive--);
 	return err;
 }