From f7ffd7cd58439cf260e6992b50775f33346a544f Mon Sep 17 00:00:00 2001
From: Stanislav Kinsbursky <skinsbursky@parallels.com>
Date: Mon, 20 Aug 2012 18:00:46 +0400
Subject: [PATCH] --- yaml --- r: 333166 b: refs/heads/master c:
 b3d19c51723be69fddb64723bebb5a30fb57a483 h: refs/heads/master v: v3

---
 [refs]                  |  2 +-
 trunk/fs/nfs/callback.c | 19 +++++++++++++++++--
 trunk/fs/nfs/netns.h    |  1 +
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 7b3dd44f00ed..f22e0f347ab9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 29dcc16a8e29371e11fb58fc1292e01f30ff13c5
+refs/heads/master: b3d19c51723be69fddb64723bebb5a30fb57a483
diff --git a/trunk/fs/nfs/callback.c b/trunk/fs/nfs/callback.c
index baafa0f1e555..6dfdc8311f27 100644
--- a/trunk/fs/nfs/callback.c
+++ b/trunk/fs/nfs/callback.c
@@ -260,10 +260,25 @@ static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
 	return 0;
 }
 
+static void nfs_callback_down_net(u32 minorversion, struct svc_serv *serv, struct net *net)
+{
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+	if (--nn->cb_users[minorversion])
+		return;
+
+	dprintk("NFS: destroy per-net callback data; net=%p\n", net);
+	svc_shutdown_net(serv, net);
+}
+
 static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
 {
+	struct nfs_net *nn = net_generic(net, nfs_net_id);
 	int ret;
 
+	if (nn->cb_users[minorversion]++)
+		return 0;
+
 	dprintk("NFS: create per-net callback data; net=%p\n", net);
 
 	ret = svc_bind(serv, net);
@@ -378,7 +393,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	return ret;
 
 err_start:
-	svc_shutdown_net(serv, net);
+	nfs_callback_down_net(minorversion, serv, net);
 	dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
 	goto err_net;
 }
@@ -391,10 +406,10 @@ void nfs_callback_down(int minorversion, struct net *net)
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
 
 	mutex_lock(&nfs_callback_mutex);
+	nfs_callback_down_net(minorversion, cb_info->serv, net);
 	cb_info->users--;
 	if (cb_info->users == 0 && cb_info->task != NULL) {
 		kthread_stop(cb_info->task);
-		svc_shutdown_net(cb_info->serv, net);
 		svc_exit_thread(cb_info->rqst);
 		cb_info->serv = NULL;
 		cb_info->rqst = NULL;
diff --git a/trunk/fs/nfs/netns.h b/trunk/fs/nfs/netns.h
index 137238b012fb..b9c7f9b1f91b 100644
--- a/trunk/fs/nfs/netns.h
+++ b/trunk/fs/nfs/netns.h
@@ -24,6 +24,7 @@ struct nfs_net {
 	struct idr cb_ident_idr; /* Protected by nfs_client_lock */
 	unsigned short nfs_callback_tcpport;
 	unsigned short nfs_callback_tcpport6;
+	int cb_users[NFS4_MAX_MINOR_VERSION + 1];
 #endif
 	spinlock_t nfs_client_lock;
 	struct timespec boot_time;