bcache: convert to blk_alloc_disk/blk_cleanup_disk

Convert the bcache driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/md/bcache/super.c

@@ -890,13 +890,9 @@ static void bcache_device_free(struct bcache_device *d)
 		if (disk_added)
 			del_gendisk(disk);
 
-		if (disk->queue)
-			blk_cleanup_queue(disk->queue);
-
+		blk_cleanup_disk(disk);
 		ida_simple_remove(&bcache_device_idx,
 				  first_minor_to_idx(disk->first_minor));
-		if (disk_added)
-			put_disk(disk);
 	}
 
 	bioset_exit(&d->bio_split);
@@ -946,7 +942,7 @@ static int bcache_device_init(struct bcache_device *d, unsigned int block_size,
 			BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER))
 		goto err;
 
-	d->disk = alloc_disk(BCACHE_MINORS);
+	d->disk = blk_alloc_disk(NUMA_NO_NODE);
 	if (!d->disk)
 		goto err;
 
@@ -955,14 +951,11 @@ static int bcache_device_init(struct bcache_device *d, unsigned int block_size,
 
 	d->disk->major		= bcache_major;
 	d->disk->first_minor	= idx_to_first_minor(idx);
+	d->disk->minors		= BCACHE_MINORS;
 	d->disk->fops		= ops;
 	d->disk->private_data	= d;
 
-	q = blk_alloc_queue(NUMA_NO_NODE);
-	if (!q)
-		return -ENOMEM;
-
-	d->disk->queue			= q;
+	q = d->disk->queue;
 	q->limits.max_hw_sectors	= UINT_MAX;
 	q->limits.max_sectors		= UINT_MAX;
 	q->limits.max_segment_size	= UINT_MAX;