xpram: convert to blk_alloc_disk/blk_cleanup_disk

Convert the xpram 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>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/s390/block/xpram.c

@@ -56,7 +56,6 @@ typedef struct {
 static xpram_device_t xpram_devices[XPRAM_MAX_DEVS];
 static unsigned int xpram_sizes[XPRAM_MAX_DEVS];
 static struct gendisk *xpram_disks[XPRAM_MAX_DEVS];
-static struct request_queue *xpram_queues[XPRAM_MAX_DEVS];
 static unsigned int xpram_pages;
 static int xpram_devs;
 
@@ -341,17 +340,13 @@ static int __init xpram_setup_blkdev(void)
 	int i, rc = -ENOMEM;
 
 	for (i = 0; i < xpram_devs; i++) {
-		xpram_disks[i] = alloc_disk(1);
+		xpram_disks[i] = blk_alloc_disk(NUMA_NO_NODE);
 		if (!xpram_disks[i])
 			goto out;
-		xpram_queues[i] = blk_alloc_queue(NUMA_NO_NODE);
-		if (!xpram_queues[i]) {
-			put_disk(xpram_disks[i]);
-			goto out;
-		}
-		blk_queue_flag_set(QUEUE_FLAG_NONROT, xpram_queues[i]);
-		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, xpram_queues[i]);
-		blk_queue_logical_block_size(xpram_queues[i], 4096);
+		blk_queue_flag_set(QUEUE_FLAG_NONROT, xpram_disks[i]->queue);
+		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM,
+				xpram_disks[i]->queue);
+		blk_queue_logical_block_size(xpram_disks[i]->queue, 4096);
 	}
 
 	/*
@@ -373,9 +368,9 @@ static int __init xpram_setup_blkdev(void)
 		offset += xpram_devices[i].size;
 		disk->major = XPRAM_MAJOR;
 		disk->first_minor = i;
+		disk->minors = 1;
 		disk->fops = &xpram_devops;
 		disk->private_data = &xpram_devices[i];
-		disk->queue = xpram_queues[i];
 		sprintf(disk->disk_name, "slram%d", i);
 		set_capacity(disk, xpram_sizes[i] << 1);
 		add_disk(disk);
@@ -383,10 +378,8 @@ static int __init xpram_setup_blkdev(void)
 
 	return 0;
 out:
-	while (i--) {
-		blk_cleanup_queue(xpram_queues[i]);
-		put_disk(xpram_disks[i]);
-	}
+	while (i--)
+		blk_cleanup_disk(xpram_disks[i]);
 	return rc;
 }
 
@@ -434,8 +427,7 @@ static void __exit xpram_exit(void)
 	int i;
 	for (i = 0; i < xpram_devs; i++) {
 		del_gendisk(xpram_disks[i]);
-		blk_cleanup_queue(xpram_queues[i]);
-		put_disk(xpram_disks[i]);
+		blk_cleanup_disk(xpram_disks[i]);
 	}
 	unregister_blkdev(XPRAM_MAJOR, XPRAM_NAME);
 	platform_device_unregister(xpram_pdev);