1 files changed, 179 insertions, 35 deletions

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index a886e692ddd0..e69b8f61189e 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -17,6 +17,9 @@
 #include <linux/freezer.h>
 #include <linux/kthread.h>
 #include <linux/sunrpc/svcauth_gss.h>
+#if defined(CONFIG_NFS_V4_1)
+#include <linux/sunrpc/bc_xprt.h>
+#endif
 
 #include <net/inet_sock.h>
 
@@ -28,11 +31,12 @@
 
 struct nfs_callback_data {
         unsigned int users;
+        struct svc_serv *serv;
         struct svc_rqst *rqst;
         struct task_struct *task;
 };
 
-static struct nfs_callback_data nfs_callback_info;
+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;
 
@@ -56,10 +60,10 @@ module_param_call(callback_tcpport, param_set_port, param_get_int,
                  &nfs_callback_set_tcpport, 0644);
 
 /*
- * This is the callback kernel thread.
+ * This is the NFSv4 callback kernel thread.
  */
 static int
-nfs_callback_svc(void *vrqstp)
+nfs4_callback_svc(void *vrqstp)
 {
         int err, preverr = 0;
         struct svc_rqst *rqstp = vrqstp;
@@ -97,20 +101,12 @@ nfs_callback_svc(void *vrqstp)
 }
 
 /*
- * Bring up the callback thread if it is not already up.
+ * Prepare to bring up the NFSv4 callback service
  */
-int nfs_callback_up(void)
+struct svc_rqst *
+nfs4_callback_up(struct svc_serv *serv)
 {
-        struct svc_serv *serv = NULL;
-        int ret = 0;
-
-        mutex_lock(&nfs_callback_mutex);
-        if (nfs_callback_info.users++ || nfs_callback_info.task != NULL)
-                goto out;
-        serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
-        ret = -ENOMEM;
-        if (!serv)
-                goto out_err;
+        int ret;
 
         ret = svc_create_xprt(serv, "tcp", PF_INET,
                                 nfs_callback_set_tcpport, SVC_SOCK_ANONYMOUS);
@@ -131,23 +127,168 @@ int nfs_callback_up(void)
                 goto out_err;
 #endif  /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */
 
-        nfs_callback_info.rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
-        if (IS_ERR(nfs_callback_info.rqst)) {
-                ret = PTR_ERR(nfs_callback_info.rqst);
-                nfs_callback_info.rqst = NULL;
+        return svc_prepare_thread(serv, &serv->sv_pools[0]);
+
+out_err:
+        if (ret == 0)
+                ret = -ENOMEM;
+        return ERR_PTR(ret);
+}
+
+#if defined(CONFIG_NFS_V4_1)
+/*
+ * The callback service for NFSv4.1 callbacks
+ */
+static int
+nfs41_callback_svc(void *vrqstp)
+{
+        struct svc_rqst *rqstp = vrqstp;
+        struct svc_serv *serv = rqstp->rq_server;
+        struct rpc_rqst *req;
+        int error;
+        DEFINE_WAIT(wq);
+
+        set_freezable();
+
+        /*
+         * FIXME: do we really need to run this under the BKL? If so, please
+         * add a comment about what it's intended to protect.
+         */
+        lock_kernel();
+        while (!kthread_should_stop()) {
+                prepare_to_wait(&serv->sv_cb_waitq, &wq, TASK_INTERRUPTIBLE);
+                spin_lock_bh(&serv->sv_cb_lock);
+                if (!list_empty(&serv->sv_cb_list)) {
+                        req = list_first_entry(&serv->sv_cb_list,
+                                        struct rpc_rqst, rq_bc_list);
+                        list_del(&req->rq_bc_list);
+                        spin_unlock_bh(&serv->sv_cb_lock);
+                        dprintk("Invoking bc_svc_process()\n");
+                        error = bc_svc_process(serv, req, rqstp);
+                        dprintk("bc_svc_process() returned w/ error code= %d\n",
+                                error);
+                } else {
+                        spin_unlock_bh(&serv->sv_cb_lock);
+                        schedule();
+                }
+                finish_wait(&serv->sv_cb_waitq, &wq);
+        }
+        unlock_kernel();
+        return 0;
+}
+
+/*
+ * Bring up the NFSv4.1 callback service
+ */
+struct svc_rqst *
+nfs41_callback_up(struct svc_serv *serv, struct rpc_xprt *xprt)
+{
+        struct svc_xprt *bc_xprt;
+        struct svc_rqst *rqstp = ERR_PTR(-ENOMEM);
+
+        dprintk("--> %s\n", __func__);
+        /* Create a svc_sock for the service */
+        bc_xprt = svc_sock_create(serv, xprt->prot);
+        if (!bc_xprt)
+                goto out;
+
+        /*
+         * Save the svc_serv in the transport so that it can
+         * be referenced when the session backchannel is initialized
+         */
+        serv->bc_xprt = bc_xprt;
+        xprt->bc_serv = serv;
+
+        INIT_LIST_HEAD(&serv->sv_cb_list);
+        spin_lock_init(&serv->sv_cb_lock);
+        init_waitqueue_head(&serv->sv_cb_waitq);
+        rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
+        if (IS_ERR(rqstp))
+                svc_sock_destroy(bc_xprt);
+out:
+        dprintk("--> %s return %p\n", __func__, rqstp);
+        return rqstp;
+}
+
+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))
+{
+        if (minorversion) {
+                *rqstpp = nfs41_callback_up(serv, xprt);
+                *callback_svc = nfs41_callback_svc;
+        }
+        return minorversion;
+}
+
+static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
+                struct nfs_callback_data *cb_info)
+{
+        if (minorversion)
+                xprt->bc_serv = cb_info->serv;
+}
+#else
+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))
+{
+        return 0;
+}
+
+static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
+                struct nfs_callback_data *cb_info)
+{
+}
+#endif /* CONFIG_NFS_V4_1 */
+
+/*
+ * Bring up the callback thread if it is not already up.
+ */
+int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
+{
+        struct svc_serv *serv = NULL;
+        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;
+
+        mutex_lock(&nfs_callback_mutex);
+        if (cb_info->users++ || cb_info->task != NULL) {
+                nfs_callback_bc_serv(minorversion, xprt, cb_info);
+                goto out;
+        }
+        serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
+        if (!serv) {
+                ret = -ENOMEM;
+                goto out_err;
+        }
+
+        minorversion_setup =  nfs_minorversion_callback_svc_setup(minorversion,
+                                        serv, xprt, &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);
 
-        nfs_callback_info.task = kthread_run(nfs_callback_svc,
-                                             nfs_callback_info.rqst,
-                                             "nfsv4-svc");
-        if (IS_ERR(nfs_callback_info.task)) {
-                ret = PTR_ERR(nfs_callback_info.task);
-                svc_exit_thread(nfs_callback_info.rqst);
-                nfs_callback_info.rqst = NULL;
-                nfs_callback_info.task = NULL;
+        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:
@@ -164,22 +305,25 @@ out:
 out_err:
         dprintk("NFS: Couldn't create callback socket or server thread; "
                 "err = %d\n", ret);
-        nfs_callback_info.users--;
+        cb_info->users--;
         goto out;
 }
 
 /*
  * Kill the callback thread if it's no longer being used.
  */
-void nfs_callback_down(void)
+void nfs_callback_down(int minorversion)
 {
+        struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+
         mutex_lock(&nfs_callback_mutex);
-        nfs_callback_info.users--;
-        if (nfs_callback_info.users == 0 && nfs_callback_info.task != NULL) {
-                kthread_stop(nfs_callback_info.task);
-                svc_exit_thread(nfs_callback_info.rqst);
-                nfs_callback_info.rqst = NULL;
-                nfs_callback_info.task = NULL;
+        cb_info->users--;
+        if (cb_info->users == 0 && cb_info->task != NULL) {
+                kthread_stop(cb_info->task);
+                svc_exit_thread(cb_info->rqst);
+                cb_info->serv = NULL;
+                cb_info->rqst = NULL;
+                cb_info->task = NULL;
         }
         mutex_unlock(&nfs_callback_mutex);
 }