block: null_blk: fix queue leak inside removing device

When queue_mode is NULL_Q_MQ and null_blk is being removed, blk_cleanup_queue() isn't called to cleanup queue, so the queue allocated won't be freed. This patch calls blk_cleanup_queue() for MQ to drain all pending requests first and release the reference counter of queue kobject, then blk_mq_free_queue() will be called in queue kobject's release handler when queue kobject's reference counter drops to zero. Signed-off-by: Ming Lei <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
vincehsu · Jan 12, 2014 · 518d00b · 518d00b
1 parent 228fdc0
commit 518d00b
Showing 1 changed file with 2 additions and 8 deletions.
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
@@ -425,10 +425,7 @@ static void null_del_dev(struct nullb *nullb)
 	list_del_init(&nullb->list);
 
 	del_gendisk(nullb->disk);
-	if (queue_mode == NULL_Q_MQ)
-		blk_mq_free_queue(nullb->q);
-	else
-		blk_cleanup_queue(nullb->q);
+	blk_cleanup_queue(nullb->q);
 	put_disk(nullb->disk);
 	kfree(nullb);
 }
@@ -578,10 +575,7 @@ static int null_add_dev(void)
 	disk = nullb->disk = alloc_disk_node(1, home_node);
 	if (!disk) {
 queue_fail:
-		if (queue_mode == NULL_Q_MQ)
-			blk_mq_free_queue(nullb->q);
-		else
-			blk_cleanup_queue(nullb->q);
+		blk_cleanup_queue(nullb->q);
 		cleanup_queues(nullb);
 err:
 		kfree(nullb);