[PATCH 3.2 028/140] dm mpath: simplify failure path of dm_multipath_init()

Ben Hutchings
2018-02-28T15:48:20Z

From: Johannes Thumshirn <morbidrsa@gmail.com>

commit ff658e9c1aae9a84dd06d46f847dc0cd2bf0dd11 upstream.

Currently the cleanup of all error cases are open-coded. Introduce a
common exit path and labels.

Signed-off-by: Johannes Thumshirn <morbidrsa@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/md/dm-mpath.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)

--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1661,16 +1661,15 @@ static int __init dm_multipath_init(void
r = dm_register_target(&multipath_target);
if (r < 0) {
DMERR("register failed %d", r);
- kmem_cache_destroy(_mpio_cache);
- return -EINVAL;
+ r = -EINVAL;
+ goto bad_register_target;
}

kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM, 0);
if (!kmultipathd) {
DMERR("failed to create workqueue kmpathd");
- dm_unregister_target(&multipath_target);
- kmem_cache_destroy(_mpio_cache);
- return -ENOMEM;
+ r = -ENOMEM;
+ goto bad_alloc_kmultipathd;
}

/*
@@ -1683,16 +1682,23 @@ static int __init dm_multipath_init(void
WQ_MEM_RECLAIM);
if (!kmpath_handlerd) {
DMERR("failed to create workqueue kmpath_handlerd");
- destroy_workqueue(kmultipathd);
- dm_unregister_target(&multipath_target);
- kmem_cache_destroy(_mpio_cache);
- return -ENOMEM;
+ r = -ENOMEM;
+ goto bad_alloc_kmpath_handlerd;
}

DMINFO("version %u.%u.%u loaded",
multipath_target.version[0], multipath_target.version[1],
multipath_target.version[2]);

+ return 0;
+
+bad_alloc_kmpath_handlerd:
+ destroy_workqueue(kmultipathd);
+bad_alloc_kmultipathd:
+ dm_unregister_target(&multipath_target);
+bad_register_target:
+ kmem_cache_destroy(_mpio_cache);
+
return r;
}