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         svc_shutdown_net(serv, net);
 239         return err;
 240 }
 241
 242 static int lockd_up_net(struct svc_serv *serv, struct net *net)
 243 {
 244         struct lockd_net *ln = net_generic(net, lockd_net_id);
 245         int error;
 246
 247         if (ln->nlmsvc_users++)
 248                 return 0;
 249
 250         error = svc_bind(serv, net);
 251         if (error)
 252                 goto err_bind;
 253
 254         error = make_socks(serv, net);
 255         if (error < 0)
 256                 goto err_socks;
 257         set_grace_period(net);
 258         dprintk("lockd_up_net: per-net data created; net=%p\n", net);
 259         return 0;
 260
 261 err_socks:
 262         svc_rpcb_cleanup(serv, net);
 263 err_bind:
 264         ln->nlmsvc_users--;
 265         return error;
 266 }
 267
 268 static void lockd_down_net(struct svc_serv *serv, struct net *net)
 269 {
 270         struct lockd_net *ln = net_generic(net, lockd_net_id);
 271
 272         if (ln->nlmsvc_users) {
 273                 if (--ln->nlmsvc_users == 0) {
 274                         nlm_shutdown_hosts_net(net);
 275                         cancel_delayed_work_sync(&ln->grace_period_end);
 276                         locks_end_grace(&ln->lockd_manager);
 277                         svc_shutdown_net(serv, net);
 278                         dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
 279                 }
 280         } else {
 281                 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
 282                                 nlmsvc_task, net);
 283                 BUG();
 284         }
 285 }
 286
 287 static int lockd_start_svc(struct svc_serv *serv)
 288 {
 289         int error;
 290
 291         if (nlmsvc_rqst)
 292                 return 0;
 293
 294         /*
 295          * Create the kernel thread and wait for it to start.
 296          */
 297         nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
 298         if (IS_ERR(nlmsvc_rqst)) {
 299                 error = PTR_ERR(nlmsvc_rqst);
 300                 printk(KERN_WARNING
 301                         "lockd_up: svc_rqst allocation failed, error=%d\n",
 302                         error);
 303                 goto out_rqst;
 304         }
 305
 306         svc_sock_update_bufs(serv);
 307         serv->sv_maxconn = nlm_max_connections;
 308
 309         nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, "%s", serv->sv_name);
 310         if (IS_ERR(nlmsvc_task)) {
 311                 error = PTR_ERR(nlmsvc_task);
 312                 printk(KERN_WARNING
 313                         "lockd_up: kthread_run failed, error=%d\n", error);
 314                 goto out_task;
 315         }
 316         dprintk("lockd_up: service started\n");
 317         return 0;
 318
 319 out_task:
 320         svc_exit_thread(nlmsvc_rqst);
 321         nlmsvc_task = NULL;
 322 out_rqst:
 323         nlmsvc_rqst = NULL;
 324         return error;
 325 }
 326
 327 static struct svc_serv *lockd_create_svc(void)
 328 {
 329         struct svc_serv *serv;
 330
 331         /*
 332          * Check whether we're already up and running.
 333          */
 334         if (nlmsvc_rqst) {
 335                 /*
 336                  * Note: increase service usage, because later in case of error
 337                  * svc_destroy() will be called.
 338                  */
 339                 svc_get(nlmsvc_rqst->rq_server);
 340                 return nlmsvc_rqst->rq_server;
 341         }
 342
 343         /*
 344          * Sanity check: if there's no pid,
 345          * we should be the first user ...
 346          */
 347         if (nlmsvc_users)
 348                 printk(KERN_WARNING
 349                         "lockd_up: no pid, %d users??\n", nlmsvc_users);
 350
 351         serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
 352         if (!serv) {
 353                 printk(KERN_WARNING "lockd_up: create service failed\n");
 354                 return ERR_PTR(-ENOMEM);
 355         }
 356         dprintk("lockd_up: service created\n");
 357         return serv;
 358 }
 359
 360 /*
 361  * Bring up the lockd process if it's not already up.
 362  */
 363 int lockd_up(struct net *net)
 364 {
 365         struct svc_serv *serv;
 366         int error;
 367
 368         mutex_lock(&nlmsvc_mutex);
 369
 370         serv = lockd_create_svc();
 371         if (IS_ERR(serv)) {
 372                 error = PTR_ERR(serv);
 373                 goto err_create;
 374         }
 375
 376         error = lockd_up_net(serv, net);
 377         if (error < 0)
 378                 goto err_net;
 379
 380         error = lockd_start_svc(serv);
 381         if (error < 0)
 382                 goto err_start;
 383
 384         nlmsvc_users++;
 385         /*
 386          * Note: svc_serv structures have an initial use count of 1,
 387          * so we exit through here on both success and failure.
 388          */
 389 err_net:
 390         svc_destroy(serv);
 391 err_create:
 392         mutex_unlock(&nlmsvc_mutex);
 393         return error;
 394
 395 err_start:
 396         lockd_down_net(serv, net);
 397         goto err_net;
 398 }
 399 EXPORT_SYMBOL_GPL(lockd_up);
 400
 401 /*
 402  * Decrement the user count and bring down lockd if we're the last.
 403  */
 404 void
 405 lockd_down(struct net *net)
 406 {
 407         mutex_lock(&nlmsvc_mutex);
 408         lockd_down_net(nlmsvc_rqst->rq_server, net);
 409         if (nlmsvc_users) {
 410                 if (--nlmsvc_users)
 411                         goto out;
 412         } else {
 413                 printk(KERN_ERR "lockd_down: no users! task=%p\n",
 414                         nlmsvc_task);
 415                 BUG();
 416         }
 417
 418         if (!nlmsvc_task) {
 419                 printk(KERN_ERR "lockd_down: no lockd running.\n");
 420                 BUG();
 421         }
 422         kthread_stop(nlmsvc_task);
 423         dprintk("lockd_down: service stopped\n");
 424         svc_exit_thread(nlmsvc_rqst);
 425         dprintk("lockd_down: service destroyed\n");
 426         nlmsvc_task = NULL;
 427         nlmsvc_rqst = NULL;
 428 out:
 429         mutex_unlock(&nlmsvc_mutex);
 430 }
 431 EXPORT_SYMBOL_GPL(lockd_down);
 432
 433 #ifdef CONFIG_SYSCTL
 434
 435 /*
 436  * Sysctl parameters (same as module parameters, different interface).
 437  */
 438
 439 static struct ctl_table nlm_sysctls[] = {
 440         {
 441                 .procname       = "nlm_grace_period",
 442                 .data           = &nlm_grace_period,
 443                 .maxlen         = sizeof(unsigned long),
 444                 .mode           = 0644,
 445                 .proc_handler   = proc_doulongvec_minmax,
 446                 .extra1         = (unsigned long *) &nlm_grace_period_min,
 447                 .extra2         = (unsigned long *) &nlm_grace_period_max,
 448         },
 449         {
 450                 .procname       = "nlm_timeout",
 451                 .data           = &nlm_timeout,
 452                 .maxlen         = sizeof(unsigned long),
 453                 .mode           = 0644,
 454                 .proc_handler   = proc_doulongvec_minmax,
 455                 .extra1         = (unsigned long *) &nlm_timeout_min,
 456                 .extra2         = (unsigned long *) &nlm_timeout_max,
 457         },
 458         {
 459                 .procname       = "nlm_udpport",
 460                 .data           = &nlm_udpport,
 461                 .maxlen         = sizeof(int),
 462                 .mode           = 0644,
 463                 .proc_handler   = proc_dointvec_minmax,
 464                 .extra1         = (int *) &nlm_port_min,
 465                 .extra2         = (int *) &nlm_port_max,
 466         },
 467         {
 468                 .procname       = "nlm_tcpport",
 469                 .data           = &nlm_tcpport,
 470                 .maxlen         = sizeof(int),
 471                 .mode           = 0644,
 472                 .proc_handler   = proc_dointvec_minmax,
 473                 .extra1         = (int *) &nlm_port_min,
 474                 .extra2         = (int *) &nlm_port_max,
 475         },
 476         {
 477                 .procname       = "nsm_use_hostnames",
 478                 .data           = &nsm_use_hostnames,
 479                 .maxlen         = sizeof(int),
 480                 .mode           = 0644,
 481                 .proc_handler   = proc_dointvec,
 482         },
 483         {
 484                 .procname       = "nsm_local_state",
 485                 .data           = &nsm_local_state,
 486                 .maxlen         = sizeof(int),
 487                 .mode           = 0644,
 488                 .proc_handler   = proc_dointvec,
 489         },
 490         { }
 491 };
 492
 493 static struct ctl_table nlm_sysctl_dir[] = {
 494         {
 495                 .procname       = "nfs",
 496                 .mode           = 0555,
 497                 .child          = nlm_sysctls,
 498         },
 499         { }
 500 };
 501
 502 static struct ctl_table nlm_sysctl_root[] = {
 503         {
 504                 .procname       = "fs",
 505                 .mode           = 0555,
 506                 .child          = nlm_sysctl_dir,
 507         },
 508         { }
 509 };
 510
 511 #endif  /* CONFIG_SYSCTL */
 512
 513 /*
 514  * Module (and sysfs) parameters.
 515  */
 516
 517 #define param_set_min_max(name, type, which_strtol, min, max)           \
 518 static int param_set_##name(const char *val, struct kernel_param *kp)   \
 519 {                                                                       \
 520         char *endp;                                                     \
 521         __typeof__(type) num = which_strtol(val, &endp, 0);             \
 522         if (endp == val || *endp || num < (min) || num > (max))         \
 523                 return -EINVAL;                                         \
 524         *((type *) kp->arg) = num;                                      \
 525         return 0;                                                       \
 526 }
 527
 528 static inline int is_callback(u32 proc)
 529 {
 530         return proc == NLMPROC_GRANTED
 531                 || proc == NLMPROC_GRANTED_MSG
 532                 || proc == NLMPROC_TEST_RES
 533                 || proc == NLMPROC_LOCK_RES
 534                 || proc == NLMPROC_CANCEL_RES
 535                 || proc == NLMPROC_UNLOCK_RES
 536                 || proc == NLMPROC_NSM_NOTIFY;
 537 }
 538
 539
 540 static int lockd_authenticate(struct svc_rqst *rqstp)
 541 {
 542         rqstp->rq_client = NULL;
 543         switch (rqstp->rq_authop->flavour) {
 544                 case RPC_AUTH_NULL:
 545                 case RPC_AUTH_UNIX:
 546                         if (rqstp->rq_proc == 0)
 547                                 return SVC_OK;
 548                         if (is_callback(rqstp->rq_proc)) {
 549                                 /* Leave it to individual procedures to
 550                                  * call nlmsvc_lookup_host(rqstp)
 551                                  */
 552                                 return SVC_OK;
 553                         }
 554                         return svc_set_client(rqstp);
 555         }
 556         return SVC_DENIED;
 557 }
 558
 559
 560 param_set_min_max(port, int, simple_strtol, 0, 65535)
 561 param_set_min_max(grace_period, unsigned long, simple_strtoul,
 562                   nlm_grace_period_min, nlm_grace_period_max)
 563 param_set_min_max(timeout, unsigned long, simple_strtoul,
 564                   nlm_timeout_min, nlm_timeout_max)
 565
 566 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
 567 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
 568 MODULE_LICENSE("GPL");
 569
 570 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
 571                   &nlm_grace_period, 0644);
 572 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
 573                   &nlm_timeout, 0644);
 574 module_param_call(nlm_udpport, param_set_port, param_get_int,
 575                   &nlm_udpport, 0644);
 576 module_param_call(nlm_tcpport, param_set_port, param_get_int,
 577                   &nlm_tcpport, 0644);
 578 module_param(nsm_use_hostnames, bool, 0644);
 579 module_param(nlm_max_connections, uint, 0644);
 580
 581 static int lockd_init_net(struct net *net)
 582 {
 583         struct lockd_net *ln = net_generic(net, lockd_net_id);
 584
 585         INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
 586         INIT_LIST_HEAD(&ln->grace_list);
 587         spin_lock_init(&ln->nsm_clnt_lock);
 588         return 0;
 589 }
 590
 591 static void lockd_exit_net(struct net *net)
 592 {
 593 }
 594
 595 static struct pernet_operations lockd_net_ops = {
 596         .init = lockd_init_net,
 597         .exit = lockd_exit_net,
 598         .id = &lockd_net_id,
 599         .size = sizeof(struct lockd_net),
 600 };
 601
 602
 603 /*
 604  * Initialising and terminating the module.
 605  */
 606
 607 static int __init init_nlm(void)
 608 {
 609         int err;
 610
 611 #ifdef CONFIG_SYSCTL
 612         err = -ENOMEM;
 613         nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
 614         if (nlm_sysctl_table == NULL)
 615                 goto err_sysctl;
 616 #endif
 617         err = register_pernet_subsys(&lockd_net_ops);
 618         if (err)
 619                 goto err_pernet;
 620         return 0;
 621
 622 err_pernet:
 623 #ifdef CONFIG_SYSCTL
 624         unregister_sysctl_table(nlm_sysctl_table);
 625 err_sysctl:
 626 #endif
 627         return err;
 628 }
 629
 630 static void __exit exit_nlm(void)
 631 {
 632         /* FIXME: delete all NLM clients */
 633         nlm_shutdown_hosts();
 634         unregister_pernet_subsys(&lockd_net_ops);
 635 #ifdef CONFIG_SYSCTL
 636         unregister_sysctl_table(nlm_sysctl_table);
 637 #endif
 638 }
 639
 640 module_init(init_nlm);
 641 module_exit(exit_nlm);
 642
 643 /*
 644  * Define NLM program and procedures
 645  */
 646 static struct svc_version       nlmsvc_version1 = {
 647                 .vs_vers        = 1,
 648                 .vs_nproc       = 17,
 649                 .vs_proc        = nlmsvc_procedures,
 650                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 651 };
 652 static struct svc_version       nlmsvc_version3 = {
 653                 .vs_vers        = 3,
 654                 .vs_nproc       = 24,
 655                 .vs_proc        = nlmsvc_procedures,
 656                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 657 };
 658 #ifdef CONFIG_LOCKD_V4
 659 static struct svc_version       nlmsvc_version4 = {
 660                 .vs_vers        = 4,
 661                 .vs_nproc       = 24,
 662                 .vs_proc        = nlmsvc_procedures4,
 663                 .vs_xdrsize     = NLMSVC_XDRSIZE,
 664 };
 665 #endif
 666 static struct svc_version *     nlmsvc_version[] = {
 667         [1] = &nlmsvc_version1,
 668         [3] = &nlmsvc_version3,
 669 #ifdef CONFIG_LOCKD_V4
 670         [4] = &nlmsvc_version4,
 671 #endif
 672 };
 673
 674 static struct svc_stat          nlmsvc_stats;
 675
 676 #define NLM_NRVERS      ARRAY_SIZE(nlmsvc_version)
 677 static struct svc_program       nlmsvc_program = {
 678         .pg_prog                = NLM_PROGRAM,          /* program number */
 679         .pg_nvers               = NLM_NRVERS,           /* number of entries in nlmsvc_version */
 680         .pg_vers                = nlmsvc_version,       /* version table */
 681         .pg_name                = "lockd",              /* service name */
 682         .pg_class               = "nfsd",               /* share authentication with nfsd */
 683         .pg_stats               = &nlmsvc_stats,        /* stats table */
 684         .pg_authenticate = &lockd_authenticate  /* export authentication */
 685 };