block: factor out a blk_debugfs_remove helper

Split the debugfs removal from blk_unregister_queue into a helper so that
the it can be reused for blk_register_queue error handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221114042637.1009333-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-sysfs.c

@@ -800,6 +800,19 @@ struct kobj_type blk_queue_ktype = {
 	.release	= blk_release_queue,
 };
 
+static void blk_debugfs_remove(struct gendisk *disk)
+{
+	struct request_queue *q = disk->queue;
+
+	mutex_lock(&q->debugfs_mutex);
+	blk_trace_shutdown(q);
+	debugfs_remove_recursive(q->debugfs_dir);
+	q->debugfs_dir = NULL;
+	q->sched_debugfs_dir = NULL;
+	q->rqos_debugfs_dir = NULL;
+	mutex_unlock(&q->debugfs_mutex);
+}
+
 /**
  * blk_register_queue - register a block layer queue with sysfs
  * @disk: Disk of which the request queue should be registered with sysfs.
@@ -925,11 +938,5 @@ void blk_unregister_queue(struct gendisk *disk)
 	kobject_del(&q->kobj);
 	mutex_unlock(&q->sysfs_dir_lock);
 
-	mutex_lock(&q->debugfs_mutex);
-	blk_trace_shutdown(q);
-	debugfs_remove_recursive(q->debugfs_dir);
-	q->debugfs_dir = NULL;
-	q->sched_debugfs_dir = NULL;
-	q->rqos_debugfs_dir = NULL;
-	mutex_unlock(&q->debugfs_mutex);
+	blk_debugfs_remove(disk);
 }