SUNRPC: create unix gid cache per network namespace

v2:
1) fixed silly usage of template cache as a real one (this code left from
static global cache for all)

This patch makes unix_gid_cache cache detail allocated and registered per
network namespace context.
Thus with this patch unix_gid_cache contents for network namespace "X" are
controlled from proc file system mount for the same network namespace "X".

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index b4217dc..38a72a1 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -26,6 +26,9 @@
 
 int sunrpc_net_id;
 
+extern int unix_gid_cache_create(struct net *net);
+extern int unix_gid_cache_destroy(struct net *net);
+
 static __net_init int sunrpc_init_net(struct net *net)
 {
 	int err;
@@ -39,11 +42,17 @@
 	if (err)
 		goto err_ipmap;
 
+	err = unix_gid_cache_create(net);
+	if (err)
+		goto err_unixgid;
+
 	rpc_pipefs_init_net(net);
 	INIT_LIST_HEAD(&sn->all_clients);
 	spin_lock_init(&sn->rpc_client_lock);
 	return 0;
 
+err_unixgid:
+	ip_map_cache_destroy(net);
 err_ipmap:
 	rpc_proc_exit(net);
 err_proc:
@@ -52,6 +61,7 @@
 
 static __net_exit void sunrpc_exit_net(struct net *net)
 {
+	unix_gid_cache_destroy(net);
 	ip_map_cache_destroy(net);
 	rpc_proc_exit(net);
 }
@@ -63,8 +73,6 @@
 	.size = sizeof(struct sunrpc_net),
 };
 
-extern struct cache_detail unix_gid_cache;
-
 static int __init
 init_sunrpc(void)
 {
@@ -86,7 +94,6 @@
 #ifdef RPC_DEBUG
 	rpc_register_sysctl();
 #endif
-	cache_register(&unix_gid_cache);
 	svc_init_xprt_sock();	/* svc sock transport */
 	init_socket_xprt();	/* clnt sock transport */
 	return 0;
@@ -109,7 +116,6 @@
 	svc_cleanup_xprt_sock();
 	unregister_rpc_pipefs();
 	rpc_destroy_mempool();
-	cache_unregister(&unix_gid_cache);
 	unregister_pernet_subsys(&sunrpc_net_ops);
 #ifdef RPC_DEBUG
 	rpc_unregister_sysctl();