nfsd: introduce helpers for generic resources init and shutdown

NFSd have per-net resources and resources, used globally.
Let's move generic resources init and shutdown to separated functions since
they are going to be allocated on first NFSd service start and destroyed after
last NFSd service shutdown.
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfssvc.c

@@ -206,6 +206,37 @@ static int nfsd_init_socks(struct net *net)
 
 static bool nfsd_up = false;
 
+static int nfsd_startup_generic(int nrservs)
+{
+	int ret;
+
+	if (nfsd_up)
+		return 0;
+
+	/*
+	 * Readahead param cache - will no-op if it already exists.
+	 * (Note therefore results will be suboptimal if number of
+	 * threads is modified after nfsd start.)
+	 */
+	ret = nfsd_racache_init(2*nrservs);
+	if (ret)
+		return ret;
+	ret = nfs4_state_start();
+	if (ret)
+		goto out_racache;
+	return 0;
+
+out_racache:
+	nfsd_racache_shutdown();
+	return ret;
+}
+
+static void nfsd_shutdown_generic(void)
+{
+	nfs4_state_shutdown();
+	nfsd_racache_shutdown();
+}
+
 static int nfsd_startup_net(struct net *net)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
@@ -236,19 +267,9 @@ static int nfsd_startup(int nrservs, struct net *net)
 {
 	int ret;
 
-	if (nfsd_up)
-		return 0;
-	/*
-	 * Readahead param cache - will no-op if it already exists.
-	 * (Note therefore results will be suboptimal if number of
-	 * threads is modified after nfsd start.)
-	 */
-	ret = nfsd_racache_init(2*nrservs);
+	ret = nfsd_startup_generic(nrservs);
 	if (ret)
 		return ret;
-	ret = nfs4_state_start();
-	if (ret)
-		goto out_racache;
 	ret = nfsd_startup_net(net);
 	if (ret)
 		goto out_net;
@@ -257,9 +278,7 @@ static int nfsd_startup(int nrservs, struct net *net)
 	return 0;
 
 out_net:
-	nfs4_state_shutdown();
-out_racache:
-	nfsd_racache_shutdown();
+	nfsd_shutdown_generic();
 	return ret;
 }
 
@@ -286,8 +305,7 @@ static void nfsd_shutdown(struct net *net)
 	if (!nfsd_up)
 		return;
 	nfsd_shutdown_net(net);
-	nfs4_state_shutdown();
-	nfsd_racache_shutdown();
+	nfsd_shutdown_generic();
 	nfsd_up = false;
 }