null_blk: Fix error path in module initialization
Module couldn't release resource properly during the initialization. To
fix this issue, we will clean up the proper resource before returning.
Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 7981b74..8162475 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -766,7 +766,9 @@
static int __init null_init(void)
{
+ int ret = 0;
unsigned int i;
+ struct nullb *nullb;
if (bs > PAGE_SIZE) {
pr_warn("null_blk: invalid block size\n");
@@ -808,22 +810,29 @@
0, 0, NULL);
if (!ppa_cache) {
pr_err("null_blk: unable to create ppa cache\n");
- return -ENOMEM;
- }
- }
-
- for (i = 0; i < nr_devices; i++) {
- if (null_add_dev()) {
- unregister_blkdev(null_major, "nullb");
+ ret = -ENOMEM;
goto err_ppa;
}
}
+ for (i = 0; i < nr_devices; i++) {
+ ret = null_add_dev();
+ if (ret)
+ goto err_dev;
+ }
+
pr_info("null: module loaded\n");
return 0;
-err_ppa:
+
+err_dev:
+ while (!list_empty(&nullb_list)) {
+ nullb = list_entry(nullb_list.next, struct nullb, list);
+ null_del_dev(nullb);
+ }
kmem_cache_destroy(ppa_cache);
- return -EINVAL;
+err_ppa:
+ unregister_blkdev(null_major, "nullb");
+ return ret;
}
static void __exit null_exit(void)