xfrm: change the type of xfrm_register_km and xfrm_unregister_km

Functions xfrm_register_km and xfrm_unregister_km do always return 0,
change the type of functions to void.
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

include/net/xfrm.h

@@ -583,8 +583,8 @@ struct xfrm_mgr {
 	bool			(*is_alive)(const struct km_event *c);
 };
 
-int xfrm_register_km(struct xfrm_mgr *km);
-int xfrm_unregister_km(struct xfrm_mgr *km);
+void xfrm_register_km(struct xfrm_mgr *km);
+void xfrm_unregister_km(struct xfrm_mgr *km);
 
 struct xfrm_tunnel_skb_cb {
 	union {

net/key/af_key.c

@@ -3894,14 +3894,10 @@ static int __init ipsec_pfkey_init(void)
 	err = sock_register(&pfkey_family_ops);
 	if (err != 0)
 		goto out_unregister_pernet;
-	err = xfrm_register_km(&pfkeyv2_mgr);
-	if (err != 0)
-		goto out_sock_unregister;
+	xfrm_register_km(&pfkeyv2_mgr);
 out:
 	return err;
 
-out_sock_unregister:
-	sock_unregister(PF_KEY);
 out_unregister_pernet:
 	unregister_pernet_subsys(&pfkey_net_ops);
 out_unregister_key_proto:

net/xfrm/xfrm_state.c

@@ -2481,22 +2481,20 @@ EXPORT_SYMBOL(xfrm_user_policy);
 
 static DEFINE_SPINLOCK(xfrm_km_lock);
 
-int xfrm_register_km(struct xfrm_mgr *km)
+void xfrm_register_km(struct xfrm_mgr *km)
 {
 	spin_lock_bh(&xfrm_km_lock);
 	list_add_tail_rcu(&km->list, &xfrm_km_list);
 	spin_unlock_bh(&xfrm_km_lock);
-	return 0;
 }
 EXPORT_SYMBOL(xfrm_register_km);
 
-int xfrm_unregister_km(struct xfrm_mgr *km)
+void xfrm_unregister_km(struct xfrm_mgr *km)
 {
 	spin_lock_bh(&xfrm_km_lock);
 	list_del_rcu(&km->list);
 	spin_unlock_bh(&xfrm_km_lock);
 	synchronize_rcu();
-	return 0;
 }
 EXPORT_SYMBOL(xfrm_unregister_km);
 

net/xfrm/xfrm_user.c

@@ -3633,10 +3633,8 @@ static int __init xfrm_user_init(void)
 	rv = register_pernet_subsys(&xfrm_user_net_ops);
 	if (rv < 0)
 		return rv;
-	rv = xfrm_register_km(&netlink_mgr);
-	if (rv < 0)
-		unregister_pernet_subsys(&xfrm_user_net_ops);
-	return rv;
+	xfrm_register_km(&netlink_mgr);
+	return 0;
 }
 
 static void __exit xfrm_user_exit(void)