NFS: move per-net callback thread initialization to nfs_callback_up_net()

v4:
1) Callback transport creation routine selection by version simlified.

This new function in now called before nfs_minorversion_callback_svc_setup()).

Also few small changes:
1) current network namespace in nfs_callback_up() was replaced by transport net.
2) svc_shutdown_net() was moved prior to callback usage counter decrement
(because in case of per-net data allocation faulure svc_shutdown_net() have to
be skipped).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 87 insertions, 48 deletions

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 18efeb5f005d..a53b4e53d5dd 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -39,6 +39,32 @@ static struct svc_program nfs4_callback_program;
 
 unsigned short nfs_callback_tcpport6;
 
+static int nfs4_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+        int ret;
+
+        ret = svc_create_xprt(serv, "tcp", net, PF_INET,
+                                nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
+        if (ret <= 0)
+                goto out_err;
+        nfs_callback_tcpport = ret;
+        dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
+                        nfs_callback_tcpport, PF_INET, net);
+
+        ret = svc_create_xprt(serv, "tcp", net, PF_INET6,
+                                nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
+        if (ret > 0) {
+                nfs_callback_tcpport6 = ret;
+                dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
+                                nfs_callback_tcpport6, PF_INET6, net);
+        } else if (ret != -EAFNOSUPPORT)
+                goto out_err;
+        return 0;
+
+out_err:
+        return (ret) ? ret : -ENOMEM;
+}
+
 /*
  * This is the NFSv4 callback kernel thread.
  */
@@ -80,36 +106,21 @@ nfs4_callback_svc(void *vrqstp)
 static struct svc_rqst *
 nfs4_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 {
-        int ret;
-
-        ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET,
-                                nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
-        if (ret <= 0)
-                goto out_err;
-        nfs_callback_tcpport = ret;
-        dprintk("NFS: Callback listener port = %u (af %u)\n",
-                        nfs_callback_tcpport, PF_INET);
-
-        ret = svc_create_xprt(serv, "tcp", &init_net, PF_INET6,
-                                nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
-        if (ret > 0) {
-                nfs_callback_tcpport6 = ret;
-                dprintk("NFS: Callback listener port = %u (af %u)\n",
-                                nfs_callback_tcpport6, PF_INET6);
-        } else if (ret == -EAFNOSUPPORT)
-                ret = 0;
-        else
-                goto out_err;
-
         return svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
-
-out_err:
-        if (ret == 0)
-                ret = -ENOMEM;
-        return ERR_PTR(ret);
 }
 
 #if defined(CONFIG_NFS_V4_1)
+static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+        /*
+         * Create an svc_sock for the back channel service that shares the
+         * fore channel connection.
+         * Returns the input port (0) and sets the svc_serv bc_xprt on success
+         */
+        return svc_create_xprt(serv, "tcp-bc", net, PF_INET, 0,
+                              SVC_SOCK_ANONYMOUS);
+}
+
 /*
  * The callback service for NFSv4.1 callbacks
  */
@@ -152,19 +163,6 @@ static struct svc_rqst *
 nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
 {
         struct svc_rqst *rqstp;
-        int ret;
-
-        /*
-         * Create an svc_sock for the back channel service that shares the
-         * fore channel connection.
-         * Returns the input port (0) and sets the svc_serv bc_xprt on success
-         */
-        ret = svc_create_xprt(serv, "tcp-bc", &init_net, PF_INET, 0,
-                              SVC_SOCK_ANONYMOUS);
-        if (ret < 0) {
-                rqstp = ERR_PTR(ret);
-                goto out;
-        }
 
         /*
          * Save the svc_serv in the transport so that it can
@@ -180,7 +178,6 @@ nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
                 svc_xprt_put(serv->sv_bc_xprt);
                 serv->sv_bc_xprt = NULL;
         }
-out:
         dprintk("--> %s return %ld\n", __func__,
                 IS_ERR(rqstp) ? PTR_ERR(rqstp) : 0);
         return rqstp;
@@ -204,6 +201,11 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
                 xprt->bc_serv = cb_info->serv;
 }
 #else
+static int nfs41_callback_up_net(struct svc_serv *serv, struct net *net)
+{
+        return 0;
+}
+
 static inline int nfs_minorversion_callback_svc_setup(u32 minorversion,
                 struct svc_serv *serv, struct rpc_xprt *xprt,
                 struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
@@ -217,6 +219,44 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 }
 #endif /* CONFIG_NFS_V4_1 */
 
+static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct net *net)
+{
+        int ret;
+
+        dprintk("NFS: create per-net callback data; net=%p\n", net);
+
+        ret = svc_bind(serv, net);
+        if (ret < 0) {
+                printk(KERN_WARNING "NFS: bind callback service failed\n");
+                goto err_bind;
+        }
+
+        switch (minorversion) {
+                case 0:
+                        ret = nfs4_callback_up_net(serv, net);
+                        break;
+                case 1:
+                        ret = nfs41_callback_up_net(serv, net);
+                        break;
+                default:
+                        printk(KERN_ERR "NFS: unknown callback version: %d\n",
+                                        minorversion);
+                        ret = -EINVAL;
+                        break;
+        }
+
+        if (ret < 0) {
+                printk(KERN_ERR "NFS: callback service start failed\n");
+                goto err_socks;
+        }
+        return 0;
+
+err_socks:
+        svc_rpcb_cleanup(serv, net);
+err_bind:
+        return ret;
+}
+
 static struct svc_serv *nfs_callback_create_svc(int minorversion)
 {
         struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
@@ -267,7 +307,7 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
         char svc_name[12];
         int ret = 0;
         int minorversion_setup;
-        struct net *net = &init_net;
+        struct net *net = xprt->xprt_net;
 
         mutex_lock(&nfs_callback_mutex);
 
@@ -282,11 +322,9 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
                 goto out;
         }
 
-        ret = svc_bind(serv, net);
-        if (ret < 0) {
-                printk(KERN_WARNING "NFS: bind callback service failed\n");
-                goto out_err;
-        }
+        ret = nfs_callback_up_net(minorversion, serv, net);
+        if (ret < 0)
+                goto err_net;
 
         minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
                                         serv, xprt, &rqstp, &callback_svc);
@@ -326,10 +364,11 @@ err_create:
         mutex_unlock(&nfs_callback_mutex);
         return ret;
 out_err:
+        svc_shutdown_net(serv, net);
+err_net:
         dprintk("NFS: Couldn't create callback socket or server thread; "
                 "err = %d\n", ret);
         cb_info->users--;
-        svc_shutdown_net(serv, net);
         goto out;
 }
 
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 088a7d2e2ecb..612f5ebaabac 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -84,7 +84,7 @@ error:
 static void nfs4_destroy_callback(struct nfs_client *clp)
 {
         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
-                nfs_callback_down(clp->cl_mvops->minor_version, &init_net);
+                nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 }
 
 static void nfs4_shutdown_client(struct nfs_client *clp)