NFS: callback per-net usage counting introduced
[pandora-kernel.git] / fs / nfs / callback.c
index a528cb7..6dfdc83 100644 (file)
@@ -23,6 +23,7 @@
 #include "nfs4_fs.h"
 #include "callback.h"
 #include "internal.h"
+#include "netns.h"
 
 #define NFSDBG_FACILITY NFSDBG_CALLBACK
 
@@ -37,26 +38,25 @@ static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
 static DEFINE_MUTEX(nfs_callback_mutex);
 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;
+       struct nfs_net *nn = net_generic(net, nfs_net_id);
 
        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;
+       nn->nfs_callback_tcpport = ret;
        dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
-                       nfs_callback_tcpport, PF_INET, net);
+                       nn->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;
+               nn->nfs_callback_tcpport6 = ret;
                dprintk("NFS: Callback listener port = %u (af %u, net %p)\n",
-                               nfs_callback_tcpport6, PF_INET6, net);
+                               nn->nfs_callback_tcpport6, PF_INET6, net);
        } else if (ret != -EAFNOSUPPORT)
                goto out_err;
        return 0;
@@ -217,10 +217,68 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 }
 #endif /* CONFIG_NFS_V4_1 */
 
+static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
+                                 struct svc_serv *serv)
+{
+       struct svc_rqst *rqstp;
+       int (*callback_svc)(void *vrqstp);
+       struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+       char svc_name[12];
+       int ret;
+       int minorversion_setup;
+
+       nfs_callback_bc_serv(minorversion, xprt, serv);
+
+       if (cb_info->task)
+               return 0;
+
+       minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
+                                       serv, &rqstp, &callback_svc);
+       if (!minorversion_setup) {
+               /* v4.0 callback setup */
+               rqstp = nfs4_callback_up(serv);
+               callback_svc = nfs4_callback_svc;
+       }
+
+       if (IS_ERR(rqstp))
+               return PTR_ERR(rqstp);
+
+       svc_sock_update_bufs(serv);
+
+       sprintf(svc_name, "nfsv4.%u-svc", minorversion);
+       cb_info->serv = serv;
+       cb_info->rqst = rqstp;
+       cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
+       if (IS_ERR(cb_info->task)) {
+               ret = PTR_ERR(cb_info->task);
+               svc_exit_thread(cb_info->rqst);
+               cb_info->rqst = NULL;
+               cb_info->task = NULL;
+               return PTR_ERR(cb_info->task);
+       }
+       dprintk("nfs_callback_up: service started\n");
+       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);
@@ -252,6 +310,8 @@ static int nfs_callback_up_net(int minorversion, struct svc_serv *serv, struct n
 err_socks:
        svc_rpcb_cleanup(serv, net);
 err_bind:
+       dprintk("NFS: Couldn't create callback socket: err = %d; "
+                       "net = %p\n", ret, net);
        return ret;
 }
 
@@ -299,12 +359,8 @@ static struct svc_serv *nfs_callback_create_svc(int minorversion)
 int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 {
        struct svc_serv *serv;
-       struct svc_rqst *rqstp;
-       int (*callback_svc)(void *vrqstp);
        struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
-       char svc_name[12];
-       int ret = 0;
-       int minorversion_setup;
+       int ret;
        struct net *net = xprt->xprt_net;
 
        mutex_lock(&nfs_callback_mutex);
@@ -315,61 +371,31 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
                goto err_create;
        }
 
-       if (cb_info->users++ || cb_info->task != NULL) {
-               nfs_callback_bc_serv(minorversion, xprt, serv);
-               goto out;
-       }
-
        ret = nfs_callback_up_net(minorversion, serv, net);
        if (ret < 0)
                goto err_net;
 
-       nfs_callback_bc_serv(minorversion, xprt, serv);
-
-       minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
-                                       serv, &rqstp, &callback_svc);
-       if (!minorversion_setup) {
-               /* v4.0 callback setup */
-               rqstp = nfs4_callback_up(serv);
-               callback_svc = nfs4_callback_svc;
-       }
-
-       if (IS_ERR(rqstp)) {
-               ret = PTR_ERR(rqstp);
-               goto out_err;
-       }
-
-       svc_sock_update_bufs(serv);
+       ret = nfs_callback_start_svc(minorversion, xprt, serv);
+       if (ret < 0)
+               goto err_start;
 
-       sprintf(svc_name, "nfsv4.%u-svc", minorversion);
-       cb_info->serv = serv;
-       cb_info->rqst = rqstp;
-       cb_info->task = kthread_run(callback_svc, cb_info->rqst, svc_name);
-       if (IS_ERR(cb_info->task)) {
-               ret = PTR_ERR(cb_info->task);
-               svc_exit_thread(cb_info->rqst);
-               cb_info->rqst = NULL;
-               cb_info->task = NULL;
-               goto out_err;
-       }
-out:
+       cb_info->users++;
        /*
         * svc_create creates the svc_serv with sv_nrthreads == 1, and then
         * svc_prepare_thread increments that. So we need to call svc_destroy
         * on both success and failure so that the refcount is 1 when the
         * thread exits.
         */
+err_net:
        svc_destroy(serv);
 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--;
-       goto out;
+
+err_start:
+       nfs_callback_down_net(minorversion, serv, net);
+       dprintk("NFS: Couldn't create server thread; err = %d\n", ret);
+       goto err_net;
 }
 
 /*
@@ -380,10 +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;