xref: /linux/fs/lockd/svc.c (revision af1fd391a5118449aecda26792e40f9e8ab24123)
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 	struct net *net = &init_net;
136 	struct lockd_net *ln = net_generic(net, lockd_net_id);
137 
138 	/* try_to_freeze() is called from svc_recv() */
139 	set_freezable();
140 
141 	/* Allow SIGKILL to tell lockd to drop all of its locks */
142 	allow_signal(SIGKILL);
143 
144 	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
145 
146 	/*
147 	 * The main request loop. We don't terminate until the last
148 	 * NFS mount or NFS daemon has gone away.
149 	 */
150 	while (!kthread_should_stop()) {
151 		long timeout = MAX_SCHEDULE_TIMEOUT;
152 		RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
153 
154 		/* update sv_maxconn if it has changed */
155 		rqstp->rq_server->sv_maxconn = nlm_max_connections;
156 
157 		if (signalled()) {
158 			flush_signals(current);
159 			restart_grace();
160 			continue;
161 		}
162 
163 		timeout = nlmsvc_retry_blocked();
164 
165 		/*
166 		 * Find a socket with data available and call its
167 		 * recvfrom routine.
168 		 */
169 		err = svc_recv(rqstp, timeout);
170 		if (err == -EAGAIN || err == -EINTR)
171 			continue;
172 		dprintk("lockd: request from %s\n",
173 				svc_print_addr(rqstp, buf, sizeof(buf)));
174 
175 		svc_process(rqstp);
176 	}
177 	flush_signals(current);
178 	if (nlmsvc_ops)
179 		nlmsvc_invalidate_all();
180 	nlm_shutdown_hosts();
181 	cancel_delayed_work_sync(&ln->grace_period_end);
182 	locks_end_grace(&ln->lockd_manager);
183 	return 0;
184 }
185 
186 static int create_lockd_listener(struct svc_serv *serv, const char *name,
187 				 struct net *net, const int family,
188 				 const unsigned short port)
189 {
190 	struct svc_xprt *xprt;
191 
192 	xprt = svc_find_xprt(serv, name, net, family, 0);
193 	if (xprt == NULL)
194 		return svc_create_xprt(serv, name, net, family, port,
195 						SVC_SOCK_DEFAULTS);
196 	svc_xprt_put(xprt);
197 	return 0;
198 }
199 
200 static int create_lockd_family(struct svc_serv *serv, struct net *net,
201 			       const int family)
202 {
203 	int err;
204 
205 	err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
206 	if (err < 0)
207 		return err;
208 
209 	return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
210 }
211 
212 /*
213  * Ensure there are active UDP and TCP listeners for lockd.
214  *
215  * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
216  * local services (such as rpc.statd) still require UDP, and
217  * some NFS servers do not yet support NLM over TCP.
218  *
219  * Returns zero if all listeners are available; otherwise a
220  * negative errno value is returned.
221  */
222 static int make_socks(struct svc_serv *serv, struct net *net)
223 {
224 	static int warned;
225 	int err;
226 
227 	err = create_lockd_family(serv, net, PF_INET);
228 	if (err < 0)
229 		goto out_err;
230 
231 	err = create_lockd_family(serv, net, PF_INET6);
232 	if (err < 0 && err != -EAFNOSUPPORT)
233 		goto out_err;
234 
235 	warned = 0;
236 	return 0;
237 
238 out_err:
239 	if (warned++ == 0)
240 		printk(KERN_WARNING
241 			"lockd_up: makesock failed, error=%d\n", err);
242 	svc_shutdown_net(serv, net);
243 	return err;
244 }
245 
246 static int lockd_up_net(struct svc_serv *serv, struct net *net)
247 {
248 	struct lockd_net *ln = net_generic(net, lockd_net_id);
249 	int error;
250 
251 	if (ln->nlmsvc_users++)
252 		return 0;
253 
254 	error = svc_bind(serv, net);
255 	if (error)
256 		goto err_bind;
257 
258 	error = make_socks(serv, net);
259 	if (error < 0)
260 		goto err_bind;
261 	set_grace_period(net);
262 	dprintk("lockd_up_net: per-net data created; net=%p\n", net);
263 	return 0;
264 
265 err_bind:
266 	ln->nlmsvc_users--;
267 	return error;
268 }
269 
270 static void lockd_down_net(struct svc_serv *serv, struct net *net)
271 {
272 	struct lockd_net *ln = net_generic(net, lockd_net_id);
273 
274 	if (ln->nlmsvc_users) {
275 		if (--ln->nlmsvc_users == 0) {
276 			nlm_shutdown_hosts_net(net);
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_inetaddr_event(struct notifier_block *this,
288 	unsigned long event, void *ptr)
289 {
290 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
291 	struct sockaddr_in sin;
292 
293 	if (event != NETDEV_DOWN)
294 		goto out;
295 
296 	if (nlmsvc_rqst) {
297 		dprintk("lockd_inetaddr_event: removed %pI4\n",
298 			&ifa->ifa_local);
299 		sin.sin_family = AF_INET;
300 		sin.sin_addr.s_addr = ifa->ifa_local;
301 		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
302 			(struct sockaddr *)&sin);
303 	}
304 
305 out:
306 	return NOTIFY_DONE;
307 }
308 
309 static struct notifier_block lockd_inetaddr_notifier = {
310 	.notifier_call = lockd_inetaddr_event,
311 };
312 
313 #if IS_ENABLED(CONFIG_IPV6)
314 static int lockd_inet6addr_event(struct notifier_block *this,
315 	unsigned long event, void *ptr)
316 {
317 	struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
318 	struct sockaddr_in6 sin6;
319 
320 	if (event != NETDEV_DOWN)
321 		goto out;
322 
323 	if (nlmsvc_rqst) {
324 		dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
325 		sin6.sin6_family = AF_INET6;
326 		sin6.sin6_addr = ifa->addr;
327 		if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
328 			sin6.sin6_scope_id = ifa->idev->dev->ifindex;
329 		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
330 			(struct sockaddr *)&sin6);
331 	}
332 
333 out:
334 	return NOTIFY_DONE;
335 }
336 
337 static struct notifier_block lockd_inet6addr_notifier = {
338 	.notifier_call = lockd_inet6addr_event,
339 };
340 #endif
341 
342 static void lockd_unregister_notifiers(void)
343 {
344 	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
345 #if IS_ENABLED(CONFIG_IPV6)
346 	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
347 #endif
348 }
349 
350 static void lockd_svc_exit_thread(void)
351 {
352 	lockd_unregister_notifiers();
353 	svc_exit_thread(nlmsvc_rqst);
354 }
355 
356 static int lockd_start_svc(struct svc_serv *serv)
357 {
358 	int error;
359 
360 	if (nlmsvc_rqst)
361 		return 0;
362 
363 	/*
364 	 * Create the kernel thread and wait for it to start.
365 	 */
366 	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
367 	if (IS_ERR(nlmsvc_rqst)) {
368 		error = PTR_ERR(nlmsvc_rqst);
369 		printk(KERN_WARNING
370 			"lockd_up: svc_rqst allocation failed, error=%d\n",
371 			error);
372 		goto out_rqst;
373 	}
374 
375 	svc_sock_update_bufs(serv);
376 	serv->sv_maxconn = nlm_max_connections;
377 
378 	nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name);
379 	if (IS_ERR(nlmsvc_task)) {
380 		error = PTR_ERR(nlmsvc_task);
381 		printk(KERN_WARNING
382 			"lockd_up: kthread_run failed, error=%d\n", error);
383 		goto out_task;
384 	}
385 	nlmsvc_rqst->rq_task = nlmsvc_task;
386 	wake_up_process(nlmsvc_task);
387 
388 	dprintk("lockd_up: service started\n");
389 	return 0;
390 
391 out_task:
392 	lockd_svc_exit_thread();
393 	nlmsvc_task = NULL;
394 out_rqst:
395 	nlmsvc_rqst = NULL;
396 	return error;
397 }
398 
399 static struct svc_serv_ops lockd_sv_ops = {
400 	.svo_shutdown		= svc_rpcb_cleanup,
401 	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
402 };
403 
404 static struct svc_serv *lockd_create_svc(void)
405 {
406 	struct svc_serv *serv;
407 
408 	/*
409 	 * Check whether we're already up and running.
410 	 */
411 	if (nlmsvc_rqst) {
412 		/*
413 		 * Note: increase service usage, because later in case of error
414 		 * svc_destroy() will be called.
415 		 */
416 		svc_get(nlmsvc_rqst->rq_server);
417 		return nlmsvc_rqst->rq_server;
418 	}
419 
420 	/*
421 	 * Sanity check: if there's no pid,
422 	 * we should be the first user ...
423 	 */
424 	if (nlmsvc_users)
425 		printk(KERN_WARNING
426 			"lockd_up: no pid, %d users??\n", nlmsvc_users);
427 
428 	if (!nlm_timeout)
429 		nlm_timeout = LOCKD_DFLT_TIMEO;
430 	nlmsvc_timeout = nlm_timeout * HZ;
431 
432 	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
433 	if (!serv) {
434 		printk(KERN_WARNING "lockd_up: create service failed\n");
435 		return ERR_PTR(-ENOMEM);
436 	}
437 	register_inetaddr_notifier(&lockd_inetaddr_notifier);
438 #if IS_ENABLED(CONFIG_IPV6)
439 	register_inet6addr_notifier(&lockd_inet6addr_notifier);
440 #endif
441 	dprintk("lockd_up: service created\n");
442 	return serv;
443 }
444 
445 /*
446  * Bring up the lockd process if it's not already up.
447  */
448 int lockd_up(struct net *net)
449 {
450 	struct svc_serv *serv;
451 	int error;
452 
453 	mutex_lock(&nlmsvc_mutex);
454 
455 	serv = lockd_create_svc();
456 	if (IS_ERR(serv)) {
457 		error = PTR_ERR(serv);
458 		goto err_create;
459 	}
460 
461 	error = lockd_up_net(serv, net);
462 	if (error < 0)
463 		goto err_net;
464 
465 	error = lockd_start_svc(serv);
466 	if (error < 0)
467 		goto err_start;
468 
469 	nlmsvc_users++;
470 	/*
471 	 * Note: svc_serv structures have an initial use count of 1,
472 	 * so we exit through here on both success and failure.
473 	 */
474 err_put:
475 	svc_destroy(serv);
476 err_create:
477 	mutex_unlock(&nlmsvc_mutex);
478 	return error;
479 
480 err_start:
481 	lockd_down_net(serv, net);
482 err_net:
483 	lockd_unregister_notifiers();
484 	goto err_put;
485 }
486 EXPORT_SYMBOL_GPL(lockd_up);
487 
488 /*
489  * Decrement the user count and bring down lockd if we're the last.
490  */
491 void
492 lockd_down(struct net *net)
493 {
494 	mutex_lock(&nlmsvc_mutex);
495 	lockd_down_net(nlmsvc_rqst->rq_server, net);
496 	if (nlmsvc_users) {
497 		if (--nlmsvc_users)
498 			goto out;
499 	} else {
500 		printk(KERN_ERR "lockd_down: no users! task=%p\n",
501 			nlmsvc_task);
502 		BUG();
503 	}
504 
505 	if (!nlmsvc_task) {
506 		printk(KERN_ERR "lockd_down: no lockd running.\n");
507 		BUG();
508 	}
509 	kthread_stop(nlmsvc_task);
510 	dprintk("lockd_down: service stopped\n");
511 	lockd_svc_exit_thread();
512 	dprintk("lockd_down: service destroyed\n");
513 	nlmsvc_task = NULL;
514 	nlmsvc_rqst = NULL;
515 out:
516 	mutex_unlock(&nlmsvc_mutex);
517 }
518 EXPORT_SYMBOL_GPL(lockd_down);
519 
520 #ifdef CONFIG_SYSCTL
521 
522 /*
523  * Sysctl parameters (same as module parameters, different interface).
524  */
525 
526 static struct ctl_table nlm_sysctls[] = {
527 	{
528 		.procname	= "nlm_grace_period",
529 		.data		= &nlm_grace_period,
530 		.maxlen		= sizeof(unsigned long),
531 		.mode		= 0644,
532 		.proc_handler	= proc_doulongvec_minmax,
533 		.extra1		= (unsigned long *) &nlm_grace_period_min,
534 		.extra2		= (unsigned long *) &nlm_grace_period_max,
535 	},
536 	{
537 		.procname	= "nlm_timeout",
538 		.data		= &nlm_timeout,
539 		.maxlen		= sizeof(unsigned long),
540 		.mode		= 0644,
541 		.proc_handler	= proc_doulongvec_minmax,
542 		.extra1		= (unsigned long *) &nlm_timeout_min,
543 		.extra2		= (unsigned long *) &nlm_timeout_max,
544 	},
545 	{
546 		.procname	= "nlm_udpport",
547 		.data		= &nlm_udpport,
548 		.maxlen		= sizeof(int),
549 		.mode		= 0644,
550 		.proc_handler	= proc_dointvec_minmax,
551 		.extra1		= (int *) &nlm_port_min,
552 		.extra2		= (int *) &nlm_port_max,
553 	},
554 	{
555 		.procname	= "nlm_tcpport",
556 		.data		= &nlm_tcpport,
557 		.maxlen		= sizeof(int),
558 		.mode		= 0644,
559 		.proc_handler	= proc_dointvec_minmax,
560 		.extra1		= (int *) &nlm_port_min,
561 		.extra2		= (int *) &nlm_port_max,
562 	},
563 	{
564 		.procname	= "nsm_use_hostnames",
565 		.data		= &nsm_use_hostnames,
566 		.maxlen		= sizeof(int),
567 		.mode		= 0644,
568 		.proc_handler	= proc_dointvec,
569 	},
570 	{
571 		.procname	= "nsm_local_state",
572 		.data		= &nsm_local_state,
573 		.maxlen		= sizeof(int),
574 		.mode		= 0644,
575 		.proc_handler	= proc_dointvec,
576 	},
577 	{ }
578 };
579 
580 static struct ctl_table nlm_sysctl_dir[] = {
581 	{
582 		.procname	= "nfs",
583 		.mode		= 0555,
584 		.child		= nlm_sysctls,
585 	},
586 	{ }
587 };
588 
589 static struct ctl_table nlm_sysctl_root[] = {
590 	{
591 		.procname	= "fs",
592 		.mode		= 0555,
593 		.child		= nlm_sysctl_dir,
594 	},
595 	{ }
596 };
597 
598 #endif	/* CONFIG_SYSCTL */
599 
600 /*
601  * Module (and sysfs) parameters.
602  */
603 
604 #define param_set_min_max(name, type, which_strtol, min, max)		\
605 static int param_set_##name(const char *val, struct kernel_param *kp)	\
606 {									\
607 	char *endp;							\
608 	__typeof__(type) num = which_strtol(val, &endp, 0);		\
609 	if (endp == val || *endp || num < (min) || num > (max))		\
610 		return -EINVAL;						\
611 	*((type *) kp->arg) = num;					\
612 	return 0;							\
613 }
614 
615 static inline int is_callback(u32 proc)
616 {
617 	return proc == NLMPROC_GRANTED
618 		|| proc == NLMPROC_GRANTED_MSG
619 		|| proc == NLMPROC_TEST_RES
620 		|| proc == NLMPROC_LOCK_RES
621 		|| proc == NLMPROC_CANCEL_RES
622 		|| proc == NLMPROC_UNLOCK_RES
623 		|| proc == NLMPROC_NSM_NOTIFY;
624 }
625 
626 
627 static int lockd_authenticate(struct svc_rqst *rqstp)
628 {
629 	rqstp->rq_client = NULL;
630 	switch (rqstp->rq_authop->flavour) {
631 		case RPC_AUTH_NULL:
632 		case RPC_AUTH_UNIX:
633 			if (rqstp->rq_proc == 0)
634 				return SVC_OK;
635 			if (is_callback(rqstp->rq_proc)) {
636 				/* Leave it to individual procedures to
637 				 * call nlmsvc_lookup_host(rqstp)
638 				 */
639 				return SVC_OK;
640 			}
641 			return svc_set_client(rqstp);
642 	}
643 	return SVC_DENIED;
644 }
645 
646 
647 param_set_min_max(port, int, simple_strtol, 0, 65535)
648 param_set_min_max(grace_period, unsigned long, simple_strtoul,
649 		  nlm_grace_period_min, nlm_grace_period_max)
650 param_set_min_max(timeout, unsigned long, simple_strtoul,
651 		  nlm_timeout_min, nlm_timeout_max)
652 
653 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
654 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
655 MODULE_LICENSE("GPL");
656 
657 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
658 		  &nlm_grace_period, 0644);
659 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
660 		  &nlm_timeout, 0644);
661 module_param_call(nlm_udpport, param_set_port, param_get_int,
662 		  &nlm_udpport, 0644);
663 module_param_call(nlm_tcpport, param_set_port, param_get_int,
664 		  &nlm_tcpport, 0644);
665 module_param(nsm_use_hostnames, bool, 0644);
666 module_param(nlm_max_connections, uint, 0644);
667 
668 static int lockd_init_net(struct net *net)
669 {
670 	struct lockd_net *ln = net_generic(net, lockd_net_id);
671 
672 	INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
673 	INIT_LIST_HEAD(&ln->lockd_manager.list);
674 	ln->lockd_manager.block_opens = false;
675 	INIT_LIST_HEAD(&ln->nsm_handles);
676 	return 0;
677 }
678 
679 static void lockd_exit_net(struct net *net)
680 {
681 }
682 
683 static struct pernet_operations lockd_net_ops = {
684 	.init = lockd_init_net,
685 	.exit = lockd_exit_net,
686 	.id = &lockd_net_id,
687 	.size = sizeof(struct lockd_net),
688 };
689 
690 
691 /*
692  * Initialising and terminating the module.
693  */
694 
695 static int __init init_nlm(void)
696 {
697 	int err;
698 
699 #ifdef CONFIG_SYSCTL
700 	err = -ENOMEM;
701 	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
702 	if (nlm_sysctl_table == NULL)
703 		goto err_sysctl;
704 #endif
705 	err = register_pernet_subsys(&lockd_net_ops);
706 	if (err)
707 		goto err_pernet;
708 
709 	err = lockd_create_procfs();
710 	if (err)
711 		goto err_procfs;
712 
713 	return 0;
714 
715 err_procfs:
716 	unregister_pernet_subsys(&lockd_net_ops);
717 err_pernet:
718 #ifdef CONFIG_SYSCTL
719 	unregister_sysctl_table(nlm_sysctl_table);
720 err_sysctl:
721 #endif
722 	return err;
723 }
724 
725 static void __exit exit_nlm(void)
726 {
727 	/* FIXME: delete all NLM clients */
728 	nlm_shutdown_hosts();
729 	lockd_remove_procfs();
730 	unregister_pernet_subsys(&lockd_net_ops);
731 #ifdef CONFIG_SYSCTL
732 	unregister_sysctl_table(nlm_sysctl_table);
733 #endif
734 }
735 
736 module_init(init_nlm);
737 module_exit(exit_nlm);
738 
739 /*
740  * Define NLM program and procedures
741  */
742 static unsigned int nlmsvc_version1_count[17];
743 static const struct svc_version	nlmsvc_version1 = {
744 	.vs_vers	= 1,
745 	.vs_nproc	= 17,
746 	.vs_proc	= nlmsvc_procedures,
747 	.vs_count	= nlmsvc_version1_count,
748 	.vs_xdrsize	= NLMSVC_XDRSIZE,
749 };
750 static unsigned int nlmsvc_version3_count[24];
751 static const struct svc_version	nlmsvc_version3 = {
752 	.vs_vers	= 3,
753 	.vs_nproc	= 24,
754 	.vs_proc	= nlmsvc_procedures,
755 	.vs_count	= nlmsvc_version3_count,
756 	.vs_xdrsize	= NLMSVC_XDRSIZE,
757 };
758 #ifdef CONFIG_LOCKD_V4
759 static unsigned int nlmsvc_version4_count[24];
760 static const struct svc_version	nlmsvc_version4 = {
761 	.vs_vers	= 4,
762 	.vs_nproc	= 24,
763 	.vs_proc	= nlmsvc_procedures4,
764 	.vs_count	= nlmsvc_version4_count,
765 	.vs_xdrsize	= NLMSVC_XDRSIZE,
766 };
767 #endif
768 static const struct svc_version *nlmsvc_version[] = {
769 	[1] = &nlmsvc_version1,
770 	[3] = &nlmsvc_version3,
771 #ifdef CONFIG_LOCKD_V4
772 	[4] = &nlmsvc_version4,
773 #endif
774 };
775 
776 static struct svc_stat		nlmsvc_stats;
777 
778 #define NLM_NRVERS	ARRAY_SIZE(nlmsvc_version)
779 static struct svc_program	nlmsvc_program = {
780 	.pg_prog		= NLM_PROGRAM,		/* program number */
781 	.pg_nvers		= NLM_NRVERS,		/* number of entries in nlmsvc_version */
782 	.pg_vers		= nlmsvc_version,	/* version table */
783 	.pg_name		= "lockd",		/* service name */
784 	.pg_class		= "nfsd",		/* share authentication with nfsd */
785 	.pg_stats		= &nlmsvc_stats,	/* stats table */
786 	.pg_authenticate = &lockd_authenticate	/* export authentication */
787 };
788