xref: /openbmc/linux/fs/lockd/svc.c (revision aac5987a)
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/signal.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 #include <linux/inetdevice.h>
29 
30 #include <linux/sunrpc/types.h>
31 #include <linux/sunrpc/stats.h>
32 #include <linux/sunrpc/clnt.h>
33 #include <linux/sunrpc/svc.h>
34 #include <linux/sunrpc/svcsock.h>
35 #include <linux/sunrpc/svc_xprt.h>
36 #include <net/ip.h>
37 #include <net/addrconf.h>
38 #include <net/ipv6.h>
39 #include <linux/lockd/lockd.h>
40 #include <linux/nfs.h>
41 
42 #include "netns.h"
43 #include "procfs.h"
44 
45 #define NLMDBG_FACILITY		NLMDBG_SVC
46 #define LOCKD_BUFSIZE		(1024 + NLMSVC_XDRSIZE)
47 #define ALLOWED_SIGS		(sigmask(SIGKILL))
48 
49 static struct svc_program	nlmsvc_program;
50 
51 const struct nlmsvc_binding	*nlmsvc_ops;
52 EXPORT_SYMBOL_GPL(nlmsvc_ops);
53 
54 static DEFINE_MUTEX(nlmsvc_mutex);
55 static unsigned int		nlmsvc_users;
56 static struct task_struct	*nlmsvc_task;
57 static struct svc_rqst		*nlmsvc_rqst;
58 unsigned long			nlmsvc_timeout;
59 
60 unsigned int lockd_net_id;
61 
62 /*
63  * These can be set at insmod time (useful for NFS as root filesystem),
64  * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
65  */
66 static unsigned long		nlm_grace_period;
67 static unsigned long		nlm_timeout = LOCKD_DFLT_TIMEO;
68 static int			nlm_udpport, nlm_tcpport;
69 
70 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
71 static unsigned int		nlm_max_connections = 1024;
72 
73 /*
74  * Constants needed for the sysctl interface.
75  */
76 static const unsigned long	nlm_grace_period_min = 0;
77 static const unsigned long	nlm_grace_period_max = 240;
78 static const unsigned long	nlm_timeout_min = 3;
79 static const unsigned long	nlm_timeout_max = 20;
80 static const int		nlm_port_min = 0, nlm_port_max = 65535;
81 
82 #ifdef CONFIG_SYSCTL
83 static struct ctl_table_header * nlm_sysctl_table;
84 #endif
85 
86 static unsigned long get_lockd_grace_period(void)
87 {
88 	/* Note: nlm_timeout should always be nonzero */
89 	if (nlm_grace_period)
90 		return roundup(nlm_grace_period, nlm_timeout) * HZ;
91 	else
92 		return nlm_timeout * 5 * HZ;
93 }
94 
95 static void grace_ender(struct work_struct *grace)
96 {
97 	struct delayed_work *dwork = to_delayed_work(grace);
98 	struct lockd_net *ln = container_of(dwork, struct lockd_net,
99 					    grace_period_end);
100 
101 	locks_end_grace(&ln->lockd_manager);
102 }
103 
104 static void set_grace_period(struct net *net)
105 {
106 	unsigned long grace_period = get_lockd_grace_period();
107 	struct lockd_net *ln = net_generic(net, lockd_net_id);
108 
109 	locks_start_grace(net, &ln->lockd_manager);
110 	cancel_delayed_work_sync(&ln->grace_period_end);
111 	schedule_delayed_work(&ln->grace_period_end, grace_period);
112 }
113 
114 static void restart_grace(void)
115 {
116 	if (nlmsvc_ops) {
117 		struct net *net = &init_net;
118 		struct lockd_net *ln = net_generic(net, lockd_net_id);
119 
120 		cancel_delayed_work_sync(&ln->grace_period_end);
121 		locks_end_grace(&ln->lockd_manager);
122 		nlmsvc_invalidate_all();
123 		set_grace_period(net);
124 	}
125 }
126 
127 /*
128  * This is the lockd kernel thread
129  */
130 static int
131 lockd(void *vrqstp)
132 {
133 	int		err = 0;
134 	struct svc_rqst *rqstp = vrqstp;
135 
136 	/* try_to_freeze() is called from svc_recv() */
137 	set_freezable();
138 
139 	/* Allow SIGKILL to tell lockd to drop all of its locks */
140 	allow_signal(SIGKILL);
141 
142 	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
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_bind;
257 	set_grace_period(net);
258 	dprintk("lockd_up_net: per-net data created; net=%p\n", net);
259 	return 0;
260 
261 err_bind:
262 	ln->nlmsvc_users--;
263 	return error;
264 }
265 
266 static void lockd_down_net(struct svc_serv *serv, struct net *net)
267 {
268 	struct lockd_net *ln = net_generic(net, lockd_net_id);
269 
270 	if (ln->nlmsvc_users) {
271 		if (--ln->nlmsvc_users == 0) {
272 			nlm_shutdown_hosts_net(net);
273 			cancel_delayed_work_sync(&ln->grace_period_end);
274 			locks_end_grace(&ln->lockd_manager);
275 			svc_shutdown_net(serv, net);
276 			dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
277 		}
278 	} else {
279 		printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
280 				nlmsvc_task, net);
281 		BUG();
282 	}
283 }
284 
285 static int lockd_inetaddr_event(struct notifier_block *this,
286 	unsigned long event, void *ptr)
287 {
288 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
289 	struct sockaddr_in sin;
290 
291 	if (event != NETDEV_DOWN)
292 		goto out;
293 
294 	if (nlmsvc_rqst) {
295 		dprintk("lockd_inetaddr_event: removed %pI4\n",
296 			&ifa->ifa_local);
297 		sin.sin_family = AF_INET;
298 		sin.sin_addr.s_addr = ifa->ifa_local;
299 		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
300 			(struct sockaddr *)&sin);
301 	}
302 
303 out:
304 	return NOTIFY_DONE;
305 }
306 
307 static struct notifier_block lockd_inetaddr_notifier = {
308 	.notifier_call = lockd_inetaddr_event,
309 };
310 
311 #if IS_ENABLED(CONFIG_IPV6)
312 static int lockd_inet6addr_event(struct notifier_block *this,
313 	unsigned long event, void *ptr)
314 {
315 	struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
316 	struct sockaddr_in6 sin6;
317 
318 	if (event != NETDEV_DOWN)
319 		goto out;
320 
321 	if (nlmsvc_rqst) {
322 		dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
323 		sin6.sin6_family = AF_INET6;
324 		sin6.sin6_addr = ifa->addr;
325 		if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
326 			sin6.sin6_scope_id = ifa->idev->dev->ifindex;
327 		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
328 			(struct sockaddr *)&sin6);
329 	}
330 
331 out:
332 	return NOTIFY_DONE;
333 }
334 
335 static struct notifier_block lockd_inet6addr_notifier = {
336 	.notifier_call = lockd_inet6addr_event,
337 };
338 #endif
339 
340 static void lockd_unregister_notifiers(void)
341 {
342 	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
343 #if IS_ENABLED(CONFIG_IPV6)
344 	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
345 #endif
346 }
347 
348 static void lockd_svc_exit_thread(void)
349 {
350 	lockd_unregister_notifiers();
351 	svc_exit_thread(nlmsvc_rqst);
352 }
353 
354 static int lockd_start_svc(struct svc_serv *serv)
355 {
356 	int error;
357 
358 	if (nlmsvc_rqst)
359 		return 0;
360 
361 	/*
362 	 * Create the kernel thread and wait for it to start.
363 	 */
364 	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
365 	if (IS_ERR(nlmsvc_rqst)) {
366 		error = PTR_ERR(nlmsvc_rqst);
367 		printk(KERN_WARNING
368 			"lockd_up: svc_rqst allocation failed, error=%d\n",
369 			error);
370 		goto out_rqst;
371 	}
372 
373 	svc_sock_update_bufs(serv);
374 	serv->sv_maxconn = nlm_max_connections;
375 
376 	nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name);
377 	if (IS_ERR(nlmsvc_task)) {
378 		error = PTR_ERR(nlmsvc_task);
379 		printk(KERN_WARNING
380 			"lockd_up: kthread_run failed, error=%d\n", error);
381 		goto out_task;
382 	}
383 	nlmsvc_rqst->rq_task = nlmsvc_task;
384 	wake_up_process(nlmsvc_task);
385 
386 	dprintk("lockd_up: service started\n");
387 	return 0;
388 
389 out_task:
390 	lockd_svc_exit_thread();
391 	nlmsvc_task = NULL;
392 out_rqst:
393 	nlmsvc_rqst = NULL;
394 	return error;
395 }
396 
397 static struct svc_serv_ops lockd_sv_ops = {
398 	.svo_shutdown		= svc_rpcb_cleanup,
399 	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
400 };
401 
402 static struct svc_serv *lockd_create_svc(void)
403 {
404 	struct svc_serv *serv;
405 
406 	/*
407 	 * Check whether we're already up and running.
408 	 */
409 	if (nlmsvc_rqst) {
410 		/*
411 		 * Note: increase service usage, because later in case of error
412 		 * svc_destroy() will be called.
413 		 */
414 		svc_get(nlmsvc_rqst->rq_server);
415 		return nlmsvc_rqst->rq_server;
416 	}
417 
418 	/*
419 	 * Sanity check: if there's no pid,
420 	 * we should be the first user ...
421 	 */
422 	if (nlmsvc_users)
423 		printk(KERN_WARNING
424 			"lockd_up: no pid, %d users??\n", nlmsvc_users);
425 
426 	if (!nlm_timeout)
427 		nlm_timeout = LOCKD_DFLT_TIMEO;
428 	nlmsvc_timeout = nlm_timeout * HZ;
429 
430 	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
431 	if (!serv) {
432 		printk(KERN_WARNING "lockd_up: create service failed\n");
433 		return ERR_PTR(-ENOMEM);
434 	}
435 	register_inetaddr_notifier(&lockd_inetaddr_notifier);
436 #if IS_ENABLED(CONFIG_IPV6)
437 	register_inet6addr_notifier(&lockd_inet6addr_notifier);
438 #endif
439 	dprintk("lockd_up: service created\n");
440 	return serv;
441 }
442 
443 /*
444  * Bring up the lockd process if it's not already up.
445  */
446 int lockd_up(struct net *net)
447 {
448 	struct svc_serv *serv;
449 	int error;
450 
451 	mutex_lock(&nlmsvc_mutex);
452 
453 	serv = lockd_create_svc();
454 	if (IS_ERR(serv)) {
455 		error = PTR_ERR(serv);
456 		goto err_create;
457 	}
458 
459 	error = lockd_up_net(serv, net);
460 	if (error < 0)
461 		goto err_net;
462 
463 	error = lockd_start_svc(serv);
464 	if (error < 0)
465 		goto err_start;
466 
467 	nlmsvc_users++;
468 	/*
469 	 * Note: svc_serv structures have an initial use count of 1,
470 	 * so we exit through here on both success and failure.
471 	 */
472 err_put:
473 	svc_destroy(serv);
474 err_create:
475 	mutex_unlock(&nlmsvc_mutex);
476 	return error;
477 
478 err_start:
479 	lockd_down_net(serv, net);
480 err_net:
481 	lockd_unregister_notifiers();
482 	goto err_put;
483 }
484 EXPORT_SYMBOL_GPL(lockd_up);
485 
486 /*
487  * Decrement the user count and bring down lockd if we're the last.
488  */
489 void
490 lockd_down(struct net *net)
491 {
492 	mutex_lock(&nlmsvc_mutex);
493 	lockd_down_net(nlmsvc_rqst->rq_server, net);
494 	if (nlmsvc_users) {
495 		if (--nlmsvc_users)
496 			goto out;
497 	} else {
498 		printk(KERN_ERR "lockd_down: no users! task=%p\n",
499 			nlmsvc_task);
500 		BUG();
501 	}
502 
503 	if (!nlmsvc_task) {
504 		printk(KERN_ERR "lockd_down: no lockd running.\n");
505 		BUG();
506 	}
507 	kthread_stop(nlmsvc_task);
508 	dprintk("lockd_down: service stopped\n");
509 	lockd_svc_exit_thread();
510 	dprintk("lockd_down: service destroyed\n");
511 	nlmsvc_task = NULL;
512 	nlmsvc_rqst = NULL;
513 out:
514 	mutex_unlock(&nlmsvc_mutex);
515 }
516 EXPORT_SYMBOL_GPL(lockd_down);
517 
518 #ifdef CONFIG_SYSCTL
519 
520 /*
521  * Sysctl parameters (same as module parameters, different interface).
522  */
523 
524 static struct ctl_table nlm_sysctls[] = {
525 	{
526 		.procname	= "nlm_grace_period",
527 		.data		= &nlm_grace_period,
528 		.maxlen		= sizeof(unsigned long),
529 		.mode		= 0644,
530 		.proc_handler	= proc_doulongvec_minmax,
531 		.extra1		= (unsigned long *) &nlm_grace_period_min,
532 		.extra2		= (unsigned long *) &nlm_grace_period_max,
533 	},
534 	{
535 		.procname	= "nlm_timeout",
536 		.data		= &nlm_timeout,
537 		.maxlen		= sizeof(unsigned long),
538 		.mode		= 0644,
539 		.proc_handler	= proc_doulongvec_minmax,
540 		.extra1		= (unsigned long *) &nlm_timeout_min,
541 		.extra2		= (unsigned long *) &nlm_timeout_max,
542 	},
543 	{
544 		.procname	= "nlm_udpport",
545 		.data		= &nlm_udpport,
546 		.maxlen		= sizeof(int),
547 		.mode		= 0644,
548 		.proc_handler	= proc_dointvec_minmax,
549 		.extra1		= (int *) &nlm_port_min,
550 		.extra2		= (int *) &nlm_port_max,
551 	},
552 	{
553 		.procname	= "nlm_tcpport",
554 		.data		= &nlm_tcpport,
555 		.maxlen		= sizeof(int),
556 		.mode		= 0644,
557 		.proc_handler	= proc_dointvec_minmax,
558 		.extra1		= (int *) &nlm_port_min,
559 		.extra2		= (int *) &nlm_port_max,
560 	},
561 	{
562 		.procname	= "nsm_use_hostnames",
563 		.data		= &nsm_use_hostnames,
564 		.maxlen		= sizeof(int),
565 		.mode		= 0644,
566 		.proc_handler	= proc_dointvec,
567 	},
568 	{
569 		.procname	= "nsm_local_state",
570 		.data		= &nsm_local_state,
571 		.maxlen		= sizeof(int),
572 		.mode		= 0644,
573 		.proc_handler	= proc_dointvec,
574 	},
575 	{ }
576 };
577 
578 static struct ctl_table nlm_sysctl_dir[] = {
579 	{
580 		.procname	= "nfs",
581 		.mode		= 0555,
582 		.child		= nlm_sysctls,
583 	},
584 	{ }
585 };
586 
587 static struct ctl_table nlm_sysctl_root[] = {
588 	{
589 		.procname	= "fs",
590 		.mode		= 0555,
591 		.child		= nlm_sysctl_dir,
592 	},
593 	{ }
594 };
595 
596 #endif	/* CONFIG_SYSCTL */
597 
598 /*
599  * Module (and sysfs) parameters.
600  */
601 
602 #define param_set_min_max(name, type, which_strtol, min, max)		\
603 static int param_set_##name(const char *val, struct kernel_param *kp)	\
604 {									\
605 	char *endp;							\
606 	__typeof__(type) num = which_strtol(val, &endp, 0);		\
607 	if (endp == val || *endp || num < (min) || num > (max))		\
608 		return -EINVAL;						\
609 	*((type *) kp->arg) = num;					\
610 	return 0;							\
611 }
612 
613 static inline int is_callback(u32 proc)
614 {
615 	return proc == NLMPROC_GRANTED
616 		|| proc == NLMPROC_GRANTED_MSG
617 		|| proc == NLMPROC_TEST_RES
618 		|| proc == NLMPROC_LOCK_RES
619 		|| proc == NLMPROC_CANCEL_RES
620 		|| proc == NLMPROC_UNLOCK_RES
621 		|| proc == NLMPROC_NSM_NOTIFY;
622 }
623 
624 
625 static int lockd_authenticate(struct svc_rqst *rqstp)
626 {
627 	rqstp->rq_client = NULL;
628 	switch (rqstp->rq_authop->flavour) {
629 		case RPC_AUTH_NULL:
630 		case RPC_AUTH_UNIX:
631 			if (rqstp->rq_proc == 0)
632 				return SVC_OK;
633 			if (is_callback(rqstp->rq_proc)) {
634 				/* Leave it to individual procedures to
635 				 * call nlmsvc_lookup_host(rqstp)
636 				 */
637 				return SVC_OK;
638 			}
639 			return svc_set_client(rqstp);
640 	}
641 	return SVC_DENIED;
642 }
643 
644 
645 param_set_min_max(port, int, simple_strtol, 0, 65535)
646 param_set_min_max(grace_period, unsigned long, simple_strtoul,
647 		  nlm_grace_period_min, nlm_grace_period_max)
648 param_set_min_max(timeout, unsigned long, simple_strtoul,
649 		  nlm_timeout_min, nlm_timeout_max)
650 
651 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
652 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
653 MODULE_LICENSE("GPL");
654 
655 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
656 		  &nlm_grace_period, 0644);
657 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
658 		  &nlm_timeout, 0644);
659 module_param_call(nlm_udpport, param_set_port, param_get_int,
660 		  &nlm_udpport, 0644);
661 module_param_call(nlm_tcpport, param_set_port, param_get_int,
662 		  &nlm_tcpport, 0644);
663 module_param(nsm_use_hostnames, bool, 0644);
664 module_param(nlm_max_connections, uint, 0644);
665 
666 static int lockd_init_net(struct net *net)
667 {
668 	struct lockd_net *ln = net_generic(net, lockd_net_id);
669 
670 	INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
671 	INIT_LIST_HEAD(&ln->lockd_manager.list);
672 	ln->lockd_manager.block_opens = false;
673 	INIT_LIST_HEAD(&ln->nsm_handles);
674 	return 0;
675 }
676 
677 static void lockd_exit_net(struct net *net)
678 {
679 }
680 
681 static struct pernet_operations lockd_net_ops = {
682 	.init = lockd_init_net,
683 	.exit = lockd_exit_net,
684 	.id = &lockd_net_id,
685 	.size = sizeof(struct lockd_net),
686 };
687 
688 
689 /*
690  * Initialising and terminating the module.
691  */
692 
693 static int __init init_nlm(void)
694 {
695 	int err;
696 
697 #ifdef CONFIG_SYSCTL
698 	err = -ENOMEM;
699 	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
700 	if (nlm_sysctl_table == NULL)
701 		goto err_sysctl;
702 #endif
703 	err = register_pernet_subsys(&lockd_net_ops);
704 	if (err)
705 		goto err_pernet;
706 
707 	err = lockd_create_procfs();
708 	if (err)
709 		goto err_procfs;
710 
711 	return 0;
712 
713 err_procfs:
714 	unregister_pernet_subsys(&lockd_net_ops);
715 err_pernet:
716 #ifdef CONFIG_SYSCTL
717 	unregister_sysctl_table(nlm_sysctl_table);
718 err_sysctl:
719 #endif
720 	return err;
721 }
722 
723 static void __exit exit_nlm(void)
724 {
725 	/* FIXME: delete all NLM clients */
726 	nlm_shutdown_hosts();
727 	lockd_remove_procfs();
728 	unregister_pernet_subsys(&lockd_net_ops);
729 #ifdef CONFIG_SYSCTL
730 	unregister_sysctl_table(nlm_sysctl_table);
731 #endif
732 }
733 
734 module_init(init_nlm);
735 module_exit(exit_nlm);
736 
737 /*
738  * Define NLM program and procedures
739  */
740 static struct svc_version	nlmsvc_version1 = {
741 		.vs_vers	= 1,
742 		.vs_nproc	= 17,
743 		.vs_proc	= nlmsvc_procedures,
744 		.vs_xdrsize	= NLMSVC_XDRSIZE,
745 };
746 static struct svc_version	nlmsvc_version3 = {
747 		.vs_vers	= 3,
748 		.vs_nproc	= 24,
749 		.vs_proc	= nlmsvc_procedures,
750 		.vs_xdrsize	= NLMSVC_XDRSIZE,
751 };
752 #ifdef CONFIG_LOCKD_V4
753 static struct svc_version	nlmsvc_version4 = {
754 		.vs_vers	= 4,
755 		.vs_nproc	= 24,
756 		.vs_proc	= nlmsvc_procedures4,
757 		.vs_xdrsize	= NLMSVC_XDRSIZE,
758 };
759 #endif
760 static struct svc_version *	nlmsvc_version[] = {
761 	[1] = &nlmsvc_version1,
762 	[3] = &nlmsvc_version3,
763 #ifdef CONFIG_LOCKD_V4
764 	[4] = &nlmsvc_version4,
765 #endif
766 };
767 
768 static struct svc_stat		nlmsvc_stats;
769 
770 #define NLM_NRVERS	ARRAY_SIZE(nlmsvc_version)
771 static struct svc_program	nlmsvc_program = {
772 	.pg_prog		= NLM_PROGRAM,		/* program number */
773 	.pg_nvers		= NLM_NRVERS,		/* number of entries in nlmsvc_version */
774 	.pg_vers		= nlmsvc_version,	/* version table */
775 	.pg_name		= "lockd",		/* service name */
776 	.pg_class		= "nfsd",		/* share authentication with nfsd */
777 	.pg_stats		= &nlmsvc_stats,	/* stats table */
778 	.pg_authenticate = &lockd_authenticate	/* export authentication */
779 };
780