tipc: make tipc node table aware of net namespace

Global variables associated with node table are below:
- node table list (node_htable)
- node hash table list (tipc_node_list)
- node table lock (node_list_lock)
- node number counter (tipc_num_nodes)
- node link number counter (tipc_num_links)

To make node table support namespace, above global variables must be
moved to tipc_net structure in order to keep secret for different
namespaces. As a consequence, these variables are allocated and
initialized when namespace is created, and deallocated when namespace
is destroyed. After the change, functions associated with these
variables have to utilize a namespace pointer to access them. So
adding namespace pointer as a parameter of these functions is the
major change made in the commit.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/core.c b/net/tipc/core.c
index a230248..7b84439 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -57,12 +57,15 @@
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 
 	tn->net_id = 4711;
+	INIT_LIST_HEAD(&tn->node_list);
+	spin_lock_init(&tn->node_list_lock);
 
 	return 0;
 }
 
 static void __net_exit tipc_exit_net(struct net *net)
 {
+	tipc_net_stop(net);
 }
 
 static struct pernet_operations tipc_net_ops = {
@@ -144,7 +147,6 @@
 static void __exit tipc_exit(void)
 {
 	unregister_pernet_subsys(&tipc_net_ops);
-	tipc_net_stop();
 	tipc_bearer_cleanup();
 	tipc_netlink_stop();
 	tipc_subscr_stop();