blk-iocost: don't allow to configure bio based device

iocost is based on rq_qos, which can only work for request based device,
thus it doesn't make sense to configure iocost for bio based device.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230117070806.3857142-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-iocost.c

@@ -3187,6 +3187,11 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
 		return PTR_ERR(bdev);
 
 	disk = bdev->bd_disk;
+	if (!queue_is_mq(disk->queue)) {
+		ret = -EOPNOTSUPP;
+		goto err;
+	}
+
 	ioc = q_to_ioc(disk->queue);
 	if (!ioc) {
 		ret = blk_iocost_init(disk);
@@ -3367,6 +3372,11 @@ static ssize_t ioc_cost_model_write(struct kernfs_open_file *of, char *input,
 		return PTR_ERR(bdev);
 
 	q = bdev_get_queue(bdev);
+	if (!queue_is_mq(q)) {
+		ret = -EOPNOTSUPP;
+		goto err;
+	}
+
 	ioc = q_to_ioc(q);
 	if (!ioc) {
 		ret = blk_iocost_init(bdev->bd_disk);