[PATCH 2/2] z2ram: add error handling support for add_disk()

[Wu Bo]

We never checked for errors on add_disk() as this function
returned void. Now that is fixed.

So add error handling support for add_disk().

Signed-off-by: Wu Bo <wubo40@xxxxxxxxxx>
---
 drivers/block/z2ram.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index 4eef218..822df1d 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -318,6 +318,7 @@ static void z2_release(struct gendisk *disk, fmode_t mode)
 static int z2ram_register_disk(int minor)
 {
 	struct gendisk *disk;
+	int err;
 
 	disk = blk_mq_alloc_disk(&tag_set, NULL);
 	if (IS_ERR(disk))
@@ -333,8 +334,11 @@ static int z2ram_register_disk(int minor)
 		sprintf(disk->disk_name, "z2ram");
 
 	z2ram_gendisk[minor] = disk;
-	add_disk(disk);
-	return 0;
+	err = add_disk(disk);
+	if (err)
+		blk_cleanup_disk(disk);
+
+	return err;
 }
 
 static int __init z2_init(void)
-- 
1.8.3.1