[PATCH 2/2 v2] NFSD: Don't start lockd when only NFSv4 is running

[Kinglong Mee <kinglongmee@gmail.com>]

When starting without nfsv2 and nfsv3, nfsd should not setup lockd,
especially when rpcbind is stop.

v2:
move setting nfsd_version4's vs_rpcb_optnl option to new patch [1/2]

Reported-by: Gareth Williams <gareth@garethwilliams.me.uk>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
---
 fs/nfsd/netns.h  |  1 +
 fs/nfsd/nfssvc.c | 26 +++++++++++++++++++++-----
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index 849a7c3..d32b3aa 100644
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h
@@ -95,6 +95,7 @@ struct nfsd_net {
 	time_t nfsd4_grace;
 
 	bool nfsd_net_up;
+	bool lockd_up;
 
 	/*
 	 * Time of server startup
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 760c85a..55b5b57 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -241,6 +241,11 @@ static void nfsd_shutdown_generic(void)
 	nfsd_racache_shutdown();
 }
 
+static bool nfsd_needs_lockd(void)
+{
+	return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
+}
+
 static int nfsd_startup_net(int nrservs, struct net *net)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
@@ -255,9 +260,14 @@ static int nfsd_startup_net(int nrservs, struct net *net)
 	ret = nfsd_init_socks(net);
 	if (ret)
 		goto out_socks;
-	ret = lockd_up(net);
-	if (ret)
-		goto out_socks;
+
+	if (nfsd_needs_lockd() && !nn->lockd_up) {
+		ret = lockd_up(net);
+		if (ret)
+			goto out_socks;
+		nn->lockd_up = 1;
+	}
+
 	ret = nfs4_state_start_net(net);
 	if (ret)
 		goto out_lockd;
@@ -266,7 +276,10 @@ static int nfsd_startup_net(int nrservs, struct net *net)
 	return 0;
 
 out_lockd:
-	lockd_down(net);
+	if (nn->lockd_up) {
+		lockd_down(net);
+		nn->lockd_up = 0;
+	}
 out_socks:
 	nfsd_shutdown_generic();
 	return ret;
@@ -277,7 +290,10 @@ static void nfsd_shutdown_net(struct net *net)
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
 	nfs4_state_shutdown_net(net);
-	lockd_down(net);
+	if (nn->lockd_up) {
+		lockd_down(net);
+		nn->lockd_up = 0;
+	}
 	nn->nfsd_net_up = false;
 	nfsd_shutdown_generic();
 }
-- 
1.8.4.2