1 files changed, 58 insertions, 30 deletions

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index f588b852d41c12..8761bf8e36fc3c 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -114,6 +114,9 @@ static struct rpc_program	rpcb_program;
 static struct rpc_clnt *	rpcb_local_clnt;
 static struct rpc_clnt *	rpcb_local_clnt4;
 
+DEFINE_SPINLOCK(rpcb_clnt_lock);
+unsigned int			rpcb_users;
+
 struct rpcbind_args {
 	struct rpc_xprt *	r_xprt;
 
@@ -161,6 +164,56 @@ static void rpcb_map_release(void *data)
 	kfree(map);
 }
 
+static int rpcb_get_local(void)
+{
+	int cnt;
+
+	spin_lock(&rpcb_clnt_lock);
+	if (rpcb_users)
+		rpcb_users++;
+	cnt = rpcb_users;
+	spin_unlock(&rpcb_clnt_lock);
+
+	return cnt;
+}
+
+void rpcb_put_local(void)
+{
+	struct rpc_clnt *clnt = rpcb_local_clnt;
+	struct rpc_clnt *clnt4 = rpcb_local_clnt4;
+	int shutdown;
+
+	spin_lock(&rpcb_clnt_lock);
+	if (--rpcb_users == 0) {
+		rpcb_local_clnt = NULL;
+		rpcb_local_clnt4 = NULL;
+	}
+	shutdown = !rpcb_users;
+	spin_unlock(&rpcb_clnt_lock);
+
+	if (shutdown) {
+		/*
+		 * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
+		 */
+		if (clnt4)
+			rpc_shutdown_client(clnt4);
+		if (clnt)
+			rpc_shutdown_client(clnt);
+	}
+}
+
+static void rpcb_set_local(struct rpc_clnt *clnt, struct rpc_clnt *clnt4)
+{
+	/* Protected by rpcb_create_local_mutex */
+	rpcb_local_clnt = clnt;
+	rpcb_local_clnt4 = clnt4;
+	smp_wmb(); 
+	rpcb_users = 1;
+	dprintk("RPC:       created new rpcb local clients (rpcb_local_clnt: "
+			"%p, rpcb_local_clnt4: %p)\n", rpcb_local_clnt,
+			rpcb_local_clnt4);
+}
+
 /*
  * Returns zero on success, otherwise a negative errno value
  * is returned.
@@ -205,9 +258,7 @@ static int rpcb_create_local_unix(void)
 		clnt4 = NULL;
 	}
 
-	/* Protected by rpcb_create_local_mutex */
-	rpcb_local_clnt = clnt;
-	rpcb_local_clnt4 = clnt4;
+	rpcb_set_local(clnt, clnt4);
 
 out:
 	return result;
@@ -259,9 +310,7 @@ static int rpcb_create_local_net(void)
 		clnt4 = NULL;
 	}
 
-	/* Protected by rpcb_create_local_mutex */
-	rpcb_local_clnt = clnt;
-	rpcb_local_clnt4 = clnt4;
+	rpcb_set_local(clnt, clnt4);
 
 out:
 	return result;
@@ -271,16 +320,16 @@ out:
  * Returns zero on success, otherwise a negative errno value
  * is returned.
  */
-static int rpcb_create_local(void)
+int rpcb_create_local(void)
 {
 	static DEFINE_MUTEX(rpcb_create_local_mutex);
 	int result = 0;
 
-	if (rpcb_local_clnt)
+	if (rpcb_get_local())
 		return result;
 
 	mutex_lock(&rpcb_create_local_mutex);
-	if (rpcb_local_clnt)
+	if (rpcb_get_local())
 		goto out;
 
 	if (rpcb_create_local_unix() != 0)
@@ -382,11 +431,6 @@ int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port)
 	struct rpc_message msg = {
 		.rpc_argp	= &map,
 	};
-	int error;
-
-	error = rpcb_create_local();
-	if (error)
-		return error;
 
 	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
 			"rpcbind\n", (port ? "" : "un"),
@@ -522,11 +566,7 @@ int rpcb_v4_register(const u32 program, const u32 version,
 	struct rpc_message msg = {
 		.rpc_argp	= &map,
 	};
-	int error;
 
-	error = rpcb_create_local();
-	if (error)
-		return error;
 	if (rpcb_local_clnt4 == NULL)
 		return -EPROTONOSUPPORT;
 
@@ -1060,15 +1100,3 @@ static struct rpc_program rpcb_program = {
 	.version	= rpcb_version,
 	.stats		= &rpcb_stats,
 };
-
-/**
- * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
- *
- */
-void cleanup_rpcb_clnt(void)
-{
-	if (rpcb_local_clnt4)
-		rpc_shutdown_client(rpcb_local_clnt4);
-	if (rpcb_local_clnt)
-		rpc_shutdown_client(rpcb_local_clnt);
-}