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 <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index a2e69d2..83a598e 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -425,10 +425,7 @@
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 @@
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);
