SUNRPC: new svc_bind() routine introduced

This new routine is responsible for service registration in a specified
network context.

The idea is to separate service creation from per-net operations.

Note also: since registering service with svc_bind() can fail, the
service will be destroyed and during destruction it will try to
unregister itself from rpcbind. In this case unregistration has to be
skipped.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

6 files changed, 41 insertions, 14 deletions

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 1ead0750cdbb..b7e92ed56885 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -324,6 +324,12 @@ int lockd_up(struct net *net)
                 goto out;
         }
 
+        error = svc_bind(serv, net);
+        if (error < 0) {
+                printk(KERN_WARNING "lockd_up: bind service failed\n");
+                goto destroy_and_out;
+        }
+
         error = make_socks(serv, net);
         if (error < 0)
                 goto destroy_and_out;
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index eb95f5091c1a..26b38fb8102e 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -17,6 +17,7 @@
 #include <linux/kthread.h>
 #include <linux/sunrpc/svcauth_gss.h>
 #include <linux/sunrpc/bc_xprt.h>
+#include <linux/nsproxy.h>
 
 #include <net/inet_sock.h>
 
@@ -253,6 +254,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
         char svc_name[12];
         int ret = 0;
         int minorversion_setup;
+        struct net *net = current->nsproxy->net_ns;
 
         mutex_lock(&nfs_callback_mutex);
         if (cb_info->users++ || cb_info->task != NULL) {
@@ -265,6 +267,12 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
                 goto out_err;
         }
 
+        ret = svc_bind(serv, net);
+        if (ret < 0) {
+                printk(KERN_WARNING "NFS: bind callback service failed\n");
+                goto out_err;
+        }
+
         minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
                                         serv, xprt, &rqstp, &callback_svc);
         if (!minorversion_setup) {
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index cb4d51d8cbdb..0762f3c9e0fb 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -11,6 +11,7 @@
 #include <linux/module.h>
 #include <linux/fs_struct.h>
 #include <linux/swap.h>
+#include <linux/nsproxy.h>
 
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/svcsock.h>
@@ -330,6 +331,8 @@ static int nfsd_get_default_max_blksize(void)
 
 int nfsd_create_serv(void)
 {
+        int error;
+
         WARN_ON(!mutex_is_locked(&nfsd_mutex));
         if (nfsd_serv) {
                 svc_get(nfsd_serv);
@@ -343,6 +346,12 @@ int nfsd_create_serv(void)
         if (nfsd_serv == NULL)
                 return -ENOMEM;
 
+        error = svc_bind(nfsd_serv, current->nsproxy->net_ns);
+        if (error < 0) {
+                svc_destroy(nfsd_serv);
+                return error;
+        }
+
         set_max_drc();
         do_gettimeofday(&nfssvc_boot);          /* record boot time */
         return 0;
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 51b29ac45a8e..2b43e0214261 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -416,6 +416,7 @@ struct svc_procedure {
  */
 int svc_rpcb_setup(struct svc_serv *serv, struct net *net);
 void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net);
+int svc_bind(struct svc_serv *serv, struct net *net);
 struct svc_serv *svc_create(struct svc_program *, unsigned int,
                             void (*shutdown)(struct svc_serv *, struct net *net));
 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv,
diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index 78ac39fd9fe7..4c38b33ab8a8 100644
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -180,14 +180,16 @@ void rpcb_put_local(struct net *net)
         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
         struct rpc_clnt *clnt = sn->rpcb_local_clnt;
         struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4;
-        int shutdown;
+        int shutdown = 0;
 
         spin_lock(&sn->rpcb_clnt_lock);
-        if (--sn->rpcb_users == 0) {
-                sn->rpcb_local_clnt = NULL;
-                sn->rpcb_local_clnt4 = NULL;
+        if (sn->rpcb_users) {
+                if (--sn->rpcb_users == 0) {
+                        sn->rpcb_local_clnt = NULL;
+                        sn->rpcb_local_clnt4 = NULL;
+                }
+                shutdown = !sn->rpcb_users;
         }
-        shutdown = !sn->rpcb_users;
         spin_unlock(&sn->rpcb_clnt_lock);
 
         if (shutdown) {
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 4153846984ac..e6d542cee0f3 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -407,6 +407,14 @@ static int svc_uses_rpcbind(struct svc_serv *serv)
         return 0;
 }
 
+int svc_bind(struct svc_serv *serv, struct net *net)
+{
+        if (!svc_uses_rpcbind(serv))
+                return 0;
+        return svc_rpcb_setup(serv, net);
+}
+EXPORT_SYMBOL_GPL(svc_bind);
+
 /*
  * Create an RPC service
  */
@@ -471,15 +479,8 @@ __svc_create(struct svc_program *prog, unsigned int bufsize, int npools,
                 spin_lock_init(&pool->sp_lock);
         }
 
-        if (svc_uses_rpcbind(serv)) {
-                if (svc_rpcb_setup(serv, current->nsproxy->net_ns) < 0) {
-                        kfree(serv->sv_pools);
-                        kfree(serv);
-                        return NULL;
-                }
-                if (!serv->sv_shutdown)
-                        serv->sv_shutdown = svc_rpcb_cleanup;
-        }
+        if (svc_uses_rpcbind(serv) && (!serv->sv_shutdown))
+                serv->sv_shutdown = svc_rpcb_cleanup;
 
         return serv;
 }