[PATCH 3/3] null_blk: do not del gendisk with lightnvm

["Matias Bjørling" <m@bjorling.me>]

The gendisk structure has not been initialized when using lightnvm.
Make sure to not delete it upon exit. Also make sure that we use the
appropriate disk_name at unregistration.

Signed-off-by: Matias Bjørling <m@bjorling.me>
---
 drivers/block/null_blk.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 6184b82..fb70b54 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -435,12 +435,14 @@ static void null_del_dev(struct nullb *nullb)
 	list_del_init(&nullb->list);
 
 	if (use_lightnvm)
-		nvm_unregister(nullb->disk->disk_name);
-	del_gendisk(nullb->disk);
+		nvm_unregister(nullb->disk_name);
+	else
+		del_gendisk(nullb->disk);
 	blk_cleanup_queue(nullb->q);
 	if (queue_mode == NULL_Q_MQ)
 		blk_mq_free_tag_set(&nullb->tag_set);
-	put_disk(nullb->disk);
+	if (!use_lightnvm)
+		put_disk(nullb->disk);
 	cleanup_queues(nullb);
 	kfree(nullb);
 }
-- 
2.1.4