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

[Ben Hutchings]

3.2.100-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Johannes Thumshirn <morbidrsa@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 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;
 }