fs/lockd/svc.c

   1 /*
   2  * linux/fs/lockd/svc.c
   3  *
   4  * This is the central lockd service.
   5  *
   6  * FIXME: Separate the lockd NFS server functionality from the lockd NFS
   7  *        client functionality. Oh why didn't Sun create two separate
   8  *        services in the first place?
   9  *
  10  * Authors:     Olaf Kirch (okir@monad.swb.de)
  11  *
  12  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/sysctl.h>
  18 #include <linux/moduleparam.h>
  19
  20 #include <linux/sched.h>
  21 #include <linux/errno.h>
  22 #include <linux/in.h>
  23 #include <linux/uio.h>
  24 #include <linux/smp.h>
  25 #include <linux/mutex.h>
  26 #include <linux/kthread.h>
  27 #include <linux/freezer.h>
  28
  29 #include <linux/sunrpc/types.h>
  30 #include <linux/sunrpc/stats.h>
  31 #include <linux/sunrpc/clnt.h>
  32 #include <linux/sunrpc/svc.h>
  33 #include <linux/sunrpc/svcsock.h>
  34 #include <net/ip.h>
  35 #include <linux/lockd/lockd.h>
  36 #include <linux/nfs.h>
  37
  38 #include "netns.h"
  39
  40 #define NLMDBG_FACILITY         NLMDBG_SVC
  41 #define LOCKD_BUFSIZE           (1024 + NLMSVC_XDRSIZE)
  42 #define ALLOWED_SIGS            (sigmask(SIGKILL))
  43
  44 static struct svc_program       nlmsvc_program;
  45
  46 struct nlmsvc_binding *         nlmsvc_ops;
  47 EXPORT_SYMBOL_GPL(nlmsvc_ops);
  48
  49 static DEFINE_MUTEX(nlmsvc_mutex);
  50 static unsigned int             nlmsvc_users;
  51 static struct task_struct       *nlmsvc_task;
  52 static struct svc_rqst          *nlmsvc_rqst;
  53 unsigned long                   nlmsvc_timeout;
  54
  55 int lockd_net_id;
  56
  57 /*
  58  * These can be set at insmod time (useful for NFS as root filesystem),
  59  * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
  60  */
  61 static unsigned long            nlm_grace_period;
  62 static unsigned long            nlm_timeout = LOCKD_DFLT_TIMEO;
  63 static int                      nlm_udpport, nlm_tcpport;
  64
  65 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
  66 static unsigned int             nlm_max_connections = 1024;
  67
  68 /*
  69  * Constants needed for the sysctl interface.
  70  */
  71 static const unsigned long      nlm_grace_period_min = 0;
  72 static const unsigned long      nlm_grace_period_max = 240;
  73 static const unsigned long      nlm_timeout_min = 3;
  74 static const unsigned long      nlm_timeout_max = 20;
  75 static const int                nlm_port_min = 0, nlm_port_max = 65535;
  76
  77 #ifdef CONFIG_SYSCTL
  78 static struct ctl_table_header * nlm_sysctl_table;
  79 #endif
  80
  81 static unsigned long get_lockd_grace_period(void)
  82 {
  83         /* Note: nlm_timeout should always be nonzero */
  84         if (nlm_grace_period)
  85                 return roundup(nlm_grace_period, nlm_timeout) * HZ;
  86         else
  87                 return nlm_timeout * 5 * HZ;
  88 }
  89
  90 static void grace_ender(struct work_struct *grace)
  91 {
  92         struct delayed_work *dwork = container_of(grace, struct delayed_work,
  93                                                   work);
  94         struct lockd_net *ln = container_of(dwork, struct lockd_net,
  95                                             grace_period_end);
  96
  97         locks_end_grace(&ln->lockd_manager);
  98 }
  99
 100 static void set_grace_period(struct net *net)
 101 {
 102         unsigned long grace_period = get_lockd_grace_period();
 103         struct lockd_net *ln = net_generic(net, lockd_net_id);
 104
 105         locks_start_grace(net, &ln->lockd_manager);
 106         cancel_delayed_work_sync(&ln->grace_period_end);
 107         schedule_delayed_work(&ln->grace_period_end, grace_period);
 108 }
 109
 110 static void restart_grace(void)
 111 {
 112         if (nlmsvc_ops) {
 113                 struct net *net = &init_net;
 114                 struct lockd_net *ln = net_generic(net, lockd_net_id);
 115
 116                 cancel_delayed_work_sync(&ln->grace_period_end);
 117                 locks_end_grace(&ln->lockd_manager);
 118                 nlmsvc_invalidate_all();
 119                 set_grace_period(net);
 120         }
 121 }
 122
 123 /*
 124  * This is the lockd kernel thread
 125  */
 126 static int
 127 lockd(void *vrqstp)
 128 {
 129         int             err = 0;
 130         struct svc_rqst *rqstp = vrqstp;
 131
 132         /* try_to_freeze() is called from svc_recv() */
 133         set_freezable();
 134
 135         /* Allow SIGKILL to tell lockd to drop all of its locks */
 136         allow_signal(SIGKILL);
 137
 138         dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
 139
 140         if (!nlm_timeout)
 141                 nlm_timeout = LOCKD_DFLT_TIMEO;
 142         nlmsvc_timeout = nlm_timeout * HZ;
 143
 144         /*
 145          * The main request loop. We don't terminate until the last
 146          * NFS mount or NFS daemon has gone away.
 147          */
 148         while (!kthread_should_stop()) {
 149                 long timeout = MAX_SCHEDULE_TIMEOUT;
 150                 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 151
 152                 /* update sv_maxconn if it has changed */
 153                 rqstp->rq_server->sv_maxconn = nlm_max_connections;
 154
 155                 if (signalled()) {
 156                         flush_signals(current);
 157                         restart_grace();
 158                         continue;
 159                 }
 160
 161                 timeout = nlmsvc_retry_blocked();
 162
 163                 /*
 164                  * Find a socket with data available and call its
 165                  * recvfrom routine.
 166                  */
 167                 err = svc_recv(rqstp, timeout);
 168                 if (err == -EAGAIN || err == -EINTR)
 169                         continue;
 170                 dprintk("lockd: request from %s\n",
 171                                 svc_print_addr(rqstp, buf, sizeof(buf)));
 172
 173                 svc_process(rqstp);
 174         }
 175         flush_signals(current);
 176         if (nlmsvc_ops)
 177                 nlmsvc_invalidate_all();
 178         nlm_shutdown_hosts();
 179         return 0;
 180 }
 181
 182 static int create_lockd_listener(struct svc_serv *serv, const char *name,
 183                                  struct net *net, const int family,
 184                                  const unsigned short port)
 185 {
 186         struct svc_xprt *xprt;
 187
 188         xprt = svc_find_xprt(serv, name, net, family, 0);
 189         if (xprt == NULL)
 190                 return svc_create_xprt(serv, name, net, family, port,
 191                                                 SVC_SOCK_DEFAULTS);
 192         svc_xprt_put(xprt);
 193         return 0;
 194 }
 195
 196 static int create_lockd_family(struct svc_serv *serv, struct net *net,
 197                                const int family)
 198 {
 199         int err;
 200
 201         err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
 202         if (err < 0)
 203                 return err;
 204
 205         return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
 206 }
 207
 208 /*
 209  * Ensure there are active UDP and TCP listeners for lockd.
 210  *
 211  * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
 212  * local services (such as rpc.statd) still require UDP, and
 213  * some NFS servers do not yet support NLM over TCP.
 214  *
 215  * Returns zero if all listeners are available; otherwise a
 216  * negative errno value is returned.
 217  */
 218 static int make_socks(struct svc_serv *serv, struct net *net)
 219 {
 220         static int warned;
 221         int err;
 222
 223         err = create_lockd_family(serv, net, PF_INET);
 224         if (err < 0)
 225                 goto out_err;
 226
 227         err = create_lockd_family(serv, net, PF_INET6);
 228         if (err < 0 && err != -EAFNOSUPPORT)
 229                 goto out_err;
 230
 231         warned = 0;
 232         return 0;
 233
 234 out_err:
 235         if (warned++ == 0)
 236                 printk(KERN_WARNING
 237                         "lockd_up: makesock failed, error=%d\n", err);
 238         return err;
 239 }
 240
 241 static int lockd_up_net(struct svc_serv *serv, struct net *net)
 242 {
 243         struct lockd_net *ln = net_generic(net, lockd_net_id);
 244         int error;
 245
 246         if (ln->nlmsvc_users++)
 247                 return 0;
 248
 249         error = svc_bind(serv, net);
 250         if (error)
 251                 goto err_bind;
 252
 253         error = make_socks(serv, net);
 254         if (error < 0)
 255                 goto err_socks;
 256         set_grace_period(net);
 257         dprintk("lockd_up_net: per-net data created; net=%p\n", net);
 258         return 0;
 259
 260 err_socks:
 261         svc_rpcb_cleanup(serv, net);
 262 err_bind:
 263         ln->nlmsvc_users--;
 264         return error;
 265 }
 266
 267 static void lockd_down_net(struct svc_serv *serv, struct net *net)
 268 {
 269         struct lockd_net *ln = net_generic(net, lockd_net_id);
 270
 271         if (ln->nlmsvc_users) {
 272                 if (--ln->nlmsvc_users == 0) {
 273                         nlm_shutdown_hosts_net(net);
 274                         cancel_delayed_work_sync(&ln->grace_period_end);
 275                         locks_end_grace(&ln->lockd_manager);
 276                         svc_shutdown_net(serv, net);
 277                         dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
 278                 }
 279         } else {
 280                 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
 281                                 nlmsvc_task, net);
 282                 BUG();
 283         }
 284 }
 285
 286 static int lockd_start_svc(struct svc_serv *serv)
 287 {
 288         int error;
 289
 290         if (nlmsvc_rqst)
 291                 return 0;
 292
 293         /*
 294          * Create the kernel thread and wait for it to start.
 295          */
 296         nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
 297         if (IS_ERR(nlmsvc_rqst)) {
 298                 error = PTR_ERR(nlmsvc_rqst);
 299                 printk(KERN_WARNING
 300                         "lockd_up: svc_rqst allocation failed, error=%d\n",
 301                         error);
 302                 goto out_rqst;
 303         }
 304
 305         svc_sock_update_bufs(serv);
 306         serv->sv_maxconn = nlm_max_connections;
 307
 308         nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, "%s", serv->sv_name);
 309         if (IS_ERR(nlmsvc_task)) {
 310                 error = PTR_ERR(nlmsvc_task);
 311                 printk(KERN_WARNING
 312                         "lockd_up: kthread_run failed, error=%d\n", error);
 313                 goto out_task;
 314         }
 315         dprintk("lockd_up: service started\n");
 316         return 0;
 317
 318 out_task:
 319         svc_exit_thread(nlmsvc_rqst);
 320         nlmsvc_task = NULL;
 321 out_rqst:
 322         nlmsvc_rqst = NULL;
 323         return error;
 324 }
 325
 326 static struct svc_serv *lockd_create_svc(void)
 327 {
 328         struct svc_serv *serv;
 329
 330         /*
 331          * Check whether we're already up and running.
 332          */
 333         if (nlmsvc_rqst) {
 334                 /*
 335                  * Note: increase service usage, because later in case of error
 336                  * svc_destroy() will be called.
 337                  */
 338                 svc_get(nlmsvc_rqst->rq_server);
 339                 return nlmsvc_rqst->rq_server;
 340         }
 341
 342         /*
 343          * Sanity check: if there's no pid,
 344          * we should be the first user ...
 345          */
 346         if (nlmsvc_users)
 347                 printk(KERN_WARNING
 348                         "lockd_up: no pid, %d users??\n", nlmsvc_users);
 349
 350         serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
 351         if (!serv) {
 352                 printk(KERN_WARNING "lockd_up: create service failed\n");
 353                 return ERR_PTR(-ENOMEM);
 354         }
 355         dprintk("lockd_up: service created\n");
 356         return serv;
 357 }
 358
 359 /*
 360  * Bring up the lockd process if it's not already up.
 361  */
 362 int lockd_up(struct net *net)
 363 {
 364         struct svc_serv *serv;
 365         int error;
 366
 367         mutex_lock(&nlmsvc_mutex);
 368
 369         serv = lockd_create_svc();
 370         if (IS_ERR(serv)) {
 371                 error = PTR_ERR(serv);
 372                 goto err_create;
 373         }
 374
 375         error = lockd_up_net(serv, net);
 376         if (error < 0)
 377                 goto err_net;
 378
 379         error = lockd_start_svc(serv);
 380         if (error < 0)
 381                 goto err_start;
 382
 383         nlmsvc_users++;
 384         /*
 385          * Note: svc_serv structures have an initial use count of 1,
 386          * so we exit through here on both success and failure.
 387          */
 388 err_net:
 389         svc_destroy(serv);
 390 err_create:
 391         mutex_unlock(&nlmsvc_mutex);
 392         return error;
 393
 394 err_start:
 395         lockd_down_net(serv, net);
 396         goto err_net;
 397 }
 398 EXPORT_SYMBOL_GPL(lockd_up);
 399
 400 /*
 401  * Decrement the user count and bring down lockd if we're the last.
 402  */
 403 void
 404 lockd_down(struct net *net)
 405 {
 406         mutex_lock(&nlmsvc_mutex);
 407         lockd_down_net(nlmsvc_rqst->rq_server, net);
 408         if (nlmsvc_users) {
 409                 if (--nlmsvc_users)
 410                         goto out;
 411         } else {
 412                 printk(KERN_ERR "lockd_down: no users! task=%p\n",
 413                         nlmsvc_task);
 414                 BUG();
 415         }
 416
 417         if (!nlmsvc_task) {
 418                 printk(KERN_ERR "lockd_down: no lockd running.\n");
 419                 BUG();
 420         }
 421         kthread_stop(nlmsvc_task);
 422         dprintk("lockd_down: service stopped\n");
 423         svc_exit_thread(nlmsvc_rqst);
 424         dprintk("lockd_down: service destroyed\n");
 425         nlmsvc_task = NULL;
 426         nlmsvc_rqst = NULL;
 427 out:
 428         mutex_unlock(&nlmsvc_mutex);
 429 }
 430 EXPORT_SYMBOL_GPL(lockd_down);
 431
 432 #ifdef CONFIG_SYSCTL
 433
 434 /*
 435  * Sysctl parameters (same as module parameters, different interface).
 436  */
 437
 438 static ctl_table nlm_sysctls[] = {
 439         {
 440                 .procname       = "nlm_grace_period",
 441                 .data           = &nlm_grace_period,
 442                 .maxlen         = sizeof(unsigned long),
 443                 .mode           = 0644,
 444                 .proc_handler   = proc_doulongvec_minmax,
 445                 .extra1         = (unsigned long *) &nlm_grace_period_min,
 446                 .extra2         = (unsigned long *) &nlm_grace_period_max,
 447         },
 448         {
 449                 .procname       = "nlm_timeout",
 450                 .data           = &nlm_timeout,
 451                 .maxlen         = sizeof(unsigned long),
 452                 .mode           = 0644,
 453                 .proc_handler   = proc_doulongvec_minmax,
 454                 .extra1         = (unsigned long *) &nlm_timeout_min,
 455                 .extra2         = (unsigned long *) &nlm_timeout_max,
 456         },
 457         {
 458                 .procname       = "nlm_udpport",
 459                 .data           = &nlm_udpport,
 460                 .maxlen         = sizeof(int),
 461                 .mode           = 0644,
 462                 .proc_handler   = proc_dointvec_minmax,
 463                 .extra1         = (int *) &nlm_port_min,
 464                 .extra2         = (int *) &nlm_port_max,
 465         },
 466         {
 467                 .procname       = "nlm_tcpport",
 468                 .data           = &nlm_tcpport,
 469                 .maxlen         = sizeof(int),
 470                 .mode           = 0644,
 471                 .proc_handler   = proc_dointvec_minmax,
 472                 .extra1         = (int *) &nlm_port_min,
 473                 .extra2         = (int *) &nlm_port_max,
 474         },
 475         {
 476                 .procname       = "nsm_use_hostnames",
 477                 .data           = &nsm_use_hostnames,
 478                 .maxlen         = sizeof(int),
 479                 .mode           = 0644,
 480                 .proc_handler   = proc_dointvec,
 481         },
 482         {
 483                 .procname       = "nsm_local_state",
 484                 .data           = &nsm_local_state,
 485                 .maxlen         = sizeof(int),
 486                 .mode           = 0644,
 487                 .proc_handler   = proc_dointvec,
 488         },
 489         { }
 490 };
 491
 492 static ctl_table nlm_sysctl_dir[] = {
 493         {
 494                 .procname       = "nfs",
 495                 .mode           = 0555,
 496                 .child          = nlm_sysctls,
 497         },
 498         { }
 499 };
 500
 501 static ctl_table nlm_sysctl_root[] = {
 502         {
 503                 .procname       = "fs",
 504                 .mode           = 0555,
 505                 .child          = nlm_sysctl_dir,
 506         },
 507         { }
 508 };
 509
 510 #endif  /* CONFIG_SYSCTL */
 511
 512 /*
 513  * Module (and sysfs) parameters.
 514  */
 515
 516 #define param_set_min_max(name, type, which_strtol, min, max)           \
 517 static int param_set_##name(const char *val, struct kernel_param *kp)   \
 518 {                                                                       \
 519         char *endp;                                                     \
 520         __typeof__(type) num = which_strtol(val, &endp, 0);             \
 521         if (endp == val || *endp || num < (min) || num > (max))         \
 522                 return -EINVAL;                                         \
 523         *((type *) kp->arg) = num;                                      \
 524         return 0;                                                       \
 525 }
 526
 527 static inline int is_callback(u32 proc)
 528 {
 529         return proc == NLMPROC_GRANTED
 530                 || proc == NLMPROC_GRANTED_MSG
 531                 || proc == NLMPROC_TEST_RES
 532                 || proc == NLMPROC_LOCK_RES
 533                 || proc == NLMPROC_CANCEL_RES
 534                 || proc == NLMPROC_UNLOCK_RES
 535                 || proc == NLMPROC_NSM_NOTIFY;
 536 }
 537
 538
 539 static int lockd_authenticate(struct svc_rqst *rqstp)
 540 {
 541         rqstp->rq_client = NULL;
 542         switch (rqstp->rq_authop->flavour) {
 543                 case RPC_AUTH_NULL:
 544                 case RPC_AUTH_UNIX:
 545                         if (rqstp->rq_proc == 0)
 546                                 return SVC_OK;
 547                         if (is_callback(rqstp->rq_proc)) {
 548                                 /* Leave it to individual procedures to
 549                                  * call nlmsvc_lookup_host(rqstp)
 550                                  */
 551                                 return SVC_OK;
 552                         }
 553                         return svc_set_client(rqstp);
 554         }
 555         return SVC_DENIED;
 556 }
 557
 558
 559 param_set_min_max(port, int, simple_strtol, 0, 65535)
 560 param_set_min_max(grace_period, unsigned long, simple_strtoul,
 561                   nlm_grace_period_min, nlm_grace_period_max)
 562 param_set_min_max(timeout, unsigned long, simple_strtoul,
 563                   nlm_timeout_min, nlm_timeout_max)
 564
 565 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
 566 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
 567 MODULE_LICENSE("GPL");
 568
 569 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
 570                   &nlm_grace_period, 0644);
 571 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
 572                   &nlm_timeout, 0644);
 573 module_param_call(nlm_udpport, param_set_port, param_get_int,
 574                   &nlm_udpport, 0644);
 575 module_param_call(nlm_tcpport, param_set_port, param_get_int,
 576                   &nlm_tcpport, 0644);
 577 module_param(nsm_use_hostnames, bool, 0644);
 578 module_param(nlm_max_connections, uint, 0644);
 579
 580 static int lockd_init_net(struct net *net)
 581 {
 582         struct lockd_net *ln = net_generic(net, lockd_net_id);
 583
 584         INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
 585         INIT_LIST_HEAD(&ln->grace_list);
 586         spin_lock_init(&ln->nsm_clnt_lock);
 587         return 0;
 588 }
 589
 590 static void lockd_exit_net(struct net *net)
 591 {
 592 }
 593
 594 static struct pernet_operations lockd_net_ops = {
 595         .init = lockd_init_net,
 596         .exit = lockd_exit_net,
 597         .id = &lockd_net_id,
 598         .size = sizeof(struct lockd_net),
 599 };
 600
 601
 602 /*
 603  * Initialising and terminating the module.
 604  */
 605
 606 static int __init init_nlm(void)
 607 {
 608         int err;
 609
 610 #ifdef CONFIG_SYSCTL
 611         err = -ENOMEM;
 612         nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
 613         if (nlm_sysctl_table == NULL)
 614                 goto err_sysctl;
 615 #endif
 616         err = register_pernet_subsys(&lockd_net_ops);
 617         if (err)
 618                 goto err_pernet;
 619         return 0;
 620
 621 err_pernet:
 622 #ifdef CONFIG_SYSCTL
 623         unregister_sysctl_table(nlm_sysctl_table);
 624 #endif
 625 err_sysctl:
 626         return err;
 627 }
 628
 629 static void __exit exit_nlm(void)
 630 {
 631         /* FIXME: delete all NLM clients */
 632         nlm_shutdown_hosts();
 633         unregister_pernet_subsys(&lockd_net_ops);
 634 #ifdef CONFIG_SYSCTL
 635         unregister_sysctl_table(nlm_sysctl_table);
 636 #endif
 637 }
 638
 639 module_init(init_nlm);
 640 module_exit(exit_nlm);
 641
 642 /*
 643  * Define NLM program and procedures
 644  */
 645 static struct svc_version       nlmsvc_version1 = {
 646                 .vs_vers        = 1,
 647                 .vs_nproc       = 17,
 648                 .vs_proc        = nlmsvc_procedures,
 649                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 650 };
 651 static struct svc_version       nlmsvc_version3 = {
 652                 .vs_vers        = 3,
 653                 .vs_nproc       = 24,
 654                 .vs_proc        = nlmsvc_procedures,
 655                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 656 };
 657 #ifdef CONFIG_LOCKD_V4
 658 static struct svc_version       nlmsvc_version4 = {
 659                 .vs_vers        = 4,
 660                 .vs_nproc       = 24,
 661                 .vs_proc        = nlmsvc_procedures4,
 662                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 663 };
 664 #endif
 665 static struct svc_version *     nlmsvc_version[] = {
 666         [1] = &nlmsvc_version1,
 667         [3] = &nlmsvc_version3,
 668 #ifdef CONFIG_LOCKD_V4
 669         [4] = &nlmsvc_version4,
 670 #endif
 671 };
 672
 673 static struct svc_stat          nlmsvc_stats;
 674
 675 #define NLM_NRVERS      ARRAY_SIZE(nlmsvc_version)
 676 static struct svc_program       nlmsvc_program = {
 677         .pg_prog                = NLM_PROGRAM,          /* program number */
 678         .pg_nvers               = NLM_NRVERS,           /* number of entries in nlmsvc_version */
 679         .pg_vers                = nlmsvc_version,       /* version table */
 680         .pg_name                = "lockd",              /* service name */
 681         .pg_class               = "nfsd",               /* share authentication with nfsd */
 682         .pg_stats               = &nlmsvc_stats,        /* stats table */
 683         .pg_authenticate = &lockd_authenticate  /* export authentication */
 684 };