summaryrefslogtreecommitdiffstats
path: root/fs/lockd/svc.c
blob: 0475c5a5d061e989ab90e8090563f61e3bf89cfe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/fs/lockd/svc.c
 *
 * This is the central lockd service.
 *
 * FIXME: Separate the lockd NFS server functionality from the lockd NFS
 * 	  client functionality. Oh why didn't Sun create two separate
 *	  services in the first place?
 *
 * Authors:	Olaf Kirch (okir@monad.swb.de)
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sysctl.h>
#include <linux/moduleparam.h>

#include <linux/sched/signal.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/uio.h>
#include <linux/smp.h>
#include <linux/mutex.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/inetdevice.h>

#include <linux/sunrpc/types.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/svc_xprt.h>
#include <net/ip.h>
#include <net/addrconf.h>
#include <net/ipv6.h>
#include <linux/lockd/lockd.h>
#include <linux/nfs.h>

#include "netns.h"
#include "procfs.h"

#define NLMDBG_FACILITY		NLMDBG_SVC
#define LOCKD_BUFSIZE		(1024 + NLMSVC_XDRSIZE)
#define ALLOWED_SIGS		(sigmask(SIGKILL))

static struct svc_program	nlmsvc_program;

const struct nlmsvc_binding	*nlmsvc_ops;
EXPORT_SYMBOL_GPL(nlmsvc_ops);

static DEFINE_MUTEX(nlmsvc_mutex);
static unsigned int		nlmsvc_users;
static struct svc_serv		*nlmsvc_serv;
unsigned long			nlmsvc_timeout;

unsigned int lockd_net_id;

/*
 * These can be set at insmod time (useful for NFS as root filesystem),
 * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
 */
static unsigned long		nlm_grace_period;
static unsigned long		nlm_timeout = LOCKD_DFLT_TIMEO;
static int			nlm_udpport, nlm_tcpport;

/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
static unsigned int		nlm_max_connections = 1024;

/*
 * Constants needed for the sysctl interface.
 */
static const unsigned long	nlm_grace_period_min = 0;
static const unsigned long	nlm_grace_period_max = 240;
static const unsigned long	nlm_timeout_min = 3;
static const unsigned long	nlm_timeout_max = 20;
static const int		nlm_port_min = 0, nlm_port_max = 65535;

#ifdef CONFIG_SYSCTL
static struct ctl_table_header * nlm_sysctl_table;
#endif

static unsigned long get_lockd_grace_period(void)
{
	/* Note: nlm_timeout should always be nonzero */
	if (nlm_grace_period)
		return roundup(nlm_grace_period, nlm_timeout) * HZ;
	else
		return nlm_timeout * 5 * HZ;
}

static void grace_ender(struct work_struct *grace)
{
	struct delayed_work *dwork = to_delayed_work(grace);
	struct lockd_net *ln = container_of(dwork, struct lockd_net,
					    grace_period_end);

	locks_end_grace(&ln->lockd_manager);
}

static void set_grace_period(struct net *net)
{
	unsigned long grace_period = get_lockd_grace_period();
	struct lockd_net *ln = net_generic(net, lockd_net_id);

	locks_start_grace(net, &ln->lockd_manager);
	cancel_delayed_work_sync(&ln->grace_period_end);
	schedule_delayed_work(&ln->grace_period_end, grace_period);
}

static void restart_grace(void)
{
	if (nlmsvc_ops) {
		struct net *net = &init_net;
		struct lockd_net *ln = net_generic(net, lockd_net_id);

		cancel_delayed_work_sync(&ln->grace_period_end);
		locks_end_grace(&ln->lockd_manager);
		nlmsvc_invalidate_all();
		set_grace_period(net);
	}
}

/*
 * This is the lockd kernel thread
 */
static int
lockd(void *vrqstp)
{
	int		err = 0;
	struct svc_rqst *rqstp = vrqstp;
	struct net *net = &init_net;
	struct lockd_net *ln = net_generic(net, lockd_net_id);

	/* try_to_freeze() is called from svc_recv() */
	set_freezable();

	/* Allow SIGKILL to tell lockd to drop all of its locks */
	allow_signal(SIGKILL);

	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");

	/*
	 * The main request loop. We don't terminate until the last
	 * NFS mount or NFS daemon has gone away.
	 */
	while (!kthread_should_stop()) {
		long timeout = MAX_SCHEDULE_TIMEOUT;
		RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);

		/* update sv_maxconn if it has changed */
		rqstp->rq_server->sv_maxconn = nlm_max_connections;

		if (signalled()) {
			flush_signals(current);
			restart_grace();
			continue;
		}

		timeout = nlmsvc_retry_blocked();

		/*
		 * Find a socket with data available and call its
		 * recvfrom routine.
		 */
		err = svc_recv(rqstp, timeout);
		if (err == -EAGAIN || err == -EINTR)
			continue;
		dprintk("lockd: request from %s\n",
				svc_print_addr(rqstp, buf, sizeof(buf)));

		svc_process(rqstp);
	}
	flush_signals(current);
	if (nlmsvc_ops)
		nlmsvc_invalidate_all();
	nlm_shutdown_hosts();
	cancel_delayed_work_sync(&ln->grace_period_end);
	locks_end_grace(&ln->lockd_manager);

	dprintk("lockd_down: service stopped\n");

	svc_exit_thread(rqstp);

	module_put_and_kthread_exit(0);
}

static int create_lockd_listener(struct svc_serv *serv, const char *name,
				 struct net *net, const int family,
				 const unsigned short port,
				 const struct cred *cred)
{
	struct svc_xprt *xprt;

	xprt = svc_find_xprt(serv, name, net, family, 0);
	if (xprt == NULL)
		return svc_create_xprt(serv, name, net, family, port,
						SVC_SOCK_DEFAULTS, cred);
	svc_xprt_put(xprt);
	return 0;
}

static int create_lockd_family(struct svc_serv *serv, struct net *net,
			       const int family, const struct cred *cred)
{
	int err;

	err = create_lockd_listener(serv, "udp", net, family, nlm_udpport,
			cred);
	if (err < 0)
		return err;

	return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport,
			cred);
}

/*
 * Ensure there are active UDP and TCP listeners for lockd.
 *
 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
 * local services (such as rpc.statd) still require UDP, and
 * some NFS servers do not yet support NLM over TCP.
 *
 * Returns zero if all listeners are available; otherwise a
 * negative errno value is returned.
 */
static int make_socks(struct svc_serv *serv, struct net *net,
		const struct cred *cred)
{
	static int warned;
	int err;

	err = create_lockd_family(serv, net, PF_INET, cred);
	if (err < 0)
		goto out_err;

	err = create_lockd_family(serv, net, PF_INET6, cred);
	if (err < 0 && err != -EAFNOSUPPORT)
		goto out_err;

	warned = 0;
	return 0;

out_err:
	if (warned++ == 0)
		printk(KERN_WARNING
			"lockd_up: makesock failed, error=%d\n", err);
	svc_shutdown_net(serv, net);
	return err;
}

static int lockd_up_net(struct svc_serv *serv, struct net *net,
		const struct cred *cred)
{
	struct lockd_net *ln = net_generic(net, lockd_net_id);
	int error;

	if (ln->nlmsvc_users++)
		return 0;

	error = svc_bind(serv, net);
	if (error)
		goto err_bind;

	error = make_socks(serv, net, cred);
	if (error < 0)
		goto err_bind;
	set_grace_period(net);
	dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
	return 0;

err_bind:
	ln->nlmsvc_users--;
	return error;
}

static void lockd_down_net(struct svc_serv *serv, struct net *net)
{
	struct lockd_net *ln = net_generic(net, lockd_net_id);

	if (ln->nlmsvc_users) {
		if (--ln->nlmsvc_users == 0) {
			nlm_shutdown_hosts_net(net);
			cancel_delayed_work_sync(&ln->grace_period_end);
			locks_end_grace(&ln->lockd_manager);
			svc_shutdown_net(serv, net);
			dprintk("%s: per-net data destroyed; net=%x\n",
				__func__, net->ns.inum);
		}
	} else {
		pr_err("%s: no users! net=%x\n",
			__func__, net->ns.inum);
		BUG();
	}
}

static int lockd_inetaddr_event(struct notifier_block *this,
	unsigned long event, void *ptr)
{
	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
	struct sockaddr_in sin;

	if (event != NETDEV_DOWN)
		goto out;

	if (nlmsvc_serv) {
		dprintk("lockd_inetaddr_event: removed %pI4\n",
			&ifa->ifa_local);
		sin.sin_family = AF_INET;
		sin.sin_addr.s_addr = ifa->ifa_local;
		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
	}

out:
	return NOTIFY_DONE;
}

static struct notifier_block lockd_inetaddr_notifier = {
	.notifier_call = lockd_inetaddr_event,
};

#if IS_ENABLED(CONFIG_IPV6)
static int lockd_inet6addr_event(struct notifier_block *this,
	unsigned long event, void *ptr)
{
	struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
	struct sockaddr_in6 sin6;

	if (event != NETDEV_DOWN)
		goto out;

	if (nlmsvc_serv) {
		dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
		sin6.sin6_family = AF_INET6;
		sin6.sin6_addr = ifa->addr;
		if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
			sin6.sin6_scope_id = ifa->idev->dev->ifindex;
		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
	}

out:
	return NOTIFY_DONE;
}

static struct notifier_block lockd_inet6addr_notifier = {
	.notifier_call = lockd_inet6addr_event,
};
#endif

static const struct svc_serv_ops lockd_sv_ops = {
	.svo_shutdown		= svc_rpcb_cleanup,
	.svo_function		= lockd,
	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
	.svo_module		= THIS_MODULE,
};

static int lockd_get(void)
{
	struct svc_serv *serv;
	int error;

	if (nlmsvc_serv) {
		svc_get(nlmsvc_serv);
		nlmsvc_users++;
		return 0;
	}

	/*
	 * Sanity check: if there's no pid,
	 * we should be the first user ...
	 */
	if (nlmsvc_users)
		printk(KERN_WARNING
			"lockd_up: no pid, %d users??\n", nlmsvc_users);

	if (!nlm_timeout)
		nlm_timeout = LOCKD_DFLT_TIMEO;
	nlmsvc_timeout = nlm_timeout * HZ;

	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
	if (!serv) {
		printk(KERN_WARNING "lockd_up: create service failed\n");
		return -ENOMEM;
	}

	serv->sv_maxconn = nlm_max_connections;
	error = svc_set_num_threads(serv, NULL, 1);
	/* The thread now holds the only reference */
	svc_put(serv);
	if (error < 0)
		return error;

	nlmsvc_serv = serv;
	register_inetaddr_notifier(&lockd_inetaddr_notifier);
#if IS_ENABLED(CONFIG_IPV6)
	register_inet6addr_notifier(&lockd_inet6addr_notifier);
#endif
	dprintk("lockd_up: service created\n");
	nlmsvc_users++;
	return 0;
}

static void lockd_put(void)
{
	if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
		return;
	if (--nlmsvc_users)
		return;

	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
#if IS_ENABLED(CONFIG_IPV6)
	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
#endif

	svc_set_num_threads(nlmsvc_serv, NULL, 0);
	nlmsvc_serv = NULL;
	dprintk("lockd_down: service destroyed\n");
}

/*
 * Bring up the lockd process if it's not already up.
 */
int lockd_up(struct net *net, const struct cred *cred)
{
	int error;

	mutex_lock(&nlmsvc_mutex);

	error = lockd_get();
	if (error)
		goto err;

	error = lockd_up_net(nlmsvc_serv, net, cred);
	if (error < 0) {
		lockd_put();
		goto err;
	}

err:
	mutex_unlock(&nlmsvc_mutex);
	return error;
}
EXPORT_SYMBOL_GPL(lockd_up);

/*
 * Decrement the user count and bring down lockd if we're the last.
 */
void
lockd_down(struct net *net)
{
	mutex_lock(&nlmsvc_mutex);
	lockd_down_net(nlmsvc_serv, net);
	lockd_put();
	mutex_unlock(&nlmsvc_mutex);
}
EXPORT_SYMBOL_GPL(lockd_down);

#ifdef CONFIG_SYSCTL

/*
 * Sysctl parameters (same as module parameters, different interface).
 */

static struct ctl_table nlm_sysctls[] = {
	{
		.procname	= "nlm_grace_period",
		.data		= &nlm_grace_period,
		.maxlen		= sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= proc_doulongvec_minmax,
		.extra1		= (unsigned long *) &nlm_grace_period_min,
		.extra2		= (unsigned long *) &nlm_grace_period_max,
	},
	{
		.procname	= "nlm_timeout",
		.data		= &nlm_timeout,
		.maxlen		= sizeof(unsigned long),
		.mode		= 0644,
		.proc_handler	= proc_doulongvec_minmax,
		.extra1		= (unsigned long *) &nlm_timeout_min,
		.extra2		= (unsigned long *) &nlm_timeout_max,
	},
	{
		.procname	= "nlm_udpport",
		.data		= &nlm_udpport,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= (int *) &nlm_port_min,
		.extra2		= (int *) &nlm_port_max,
	},
	{
		.procname	= "nlm_tcpport",
		.data		= &nlm_tcpport,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= (int *) &nlm_port_min,
		.extra2		= (int *) &nlm_port_max,
	},
	{
		.procname	= "nsm_use_hostnames",
		.data		= &nsm_use_hostnames,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dobool,
	},
	{
		.procname	= "nsm_local_state",
		.data		= &nsm_local_state,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec,
	},
	{ }
};

static struct ctl_table nlm_sysctl_dir[] = {
	{
		.procname	= "nfs",
		.mode		= 0555,
		.child		= nlm_sysctls,
	},
	{ }
};

static struct ctl_table nlm_sysctl_root[] = {
	{
		.procname	= "fs",
		.mode		= 0555,
		.child		= nlm_sysctl_dir,
	},
	{ }
};

#endif	/* CONFIG_SYSCTL */

/*
 * Module (and sysfs) parameters.
 */

#define param_set_min_max(name, type, which_strtol, min, max)		\
static int param_set_##name(const char *val, const struct kernel_param *kp) \
{									\
	char *endp;							\
	__typeof__(type) num = which_strtol(val, &endp, 0);		\
	if (endp == val || *endp || num < (min) || num > (max))		\
		return -EINVAL;						\
	*((type *) kp->arg) = num;					\
	return 0;							\
}

static inline int is_callback(u32 proc)
{
	return proc == NLMPROC_GRANTED
		|| proc == NLMPROC_GRANTED_MSG
		|| proc == NLMPROC_TEST_RES
		|| proc == NLMPROC_LOCK_RES
		|| proc == NLMPROC_CANCEL_RES
		|| proc == NLMPROC_UNLOCK_RES
		|| proc == NLMPROC_NSM_NOTIFY;
}


static int lockd_authenticate(struct svc_rqst *rqstp)
{
	rqstp->rq_client = NULL;
	switch (rqstp->rq_authop->flavour) {
		case RPC_AUTH_NULL:
		case RPC_AUTH_UNIX:
			rqstp->rq_auth_stat = rpc_auth_ok;
			if (rqstp->rq_proc == 0)
				return SVC_OK;
			if (is_callback(rqstp->rq_proc)) {
				/* Leave it to individual procedures to
				 * call nlmsvc_lookup_host(rqstp)
				 */
				return SVC_OK;
			}
			return svc_set_client(rqstp);
	}
	rqstp->rq_auth_stat = rpc_autherr_badcred;
	return SVC_DENIED;
}


param_set_min_max(port, int, simple_strtol, 0, 65535)
param_set_min_max(grace_period, unsigned long, simple_strtoul,
		  nlm_grace_period_min, nlm_grace_period_max)
param_set_min_max(timeout, unsigned long, simple_strtoul,
		  nlm_timeout_min, nlm_timeout_max)

MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
MODULE_LICENSE("GPL");

module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
		  &nlm_grace_period, 0644);
module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
		  &nlm_timeout, 0644);
module_param_call(nlm_udpport, param_set_port, param_get_int,
		  &nlm_udpport, 0644);
module_param_call(nlm_tcpport, param_set_port, param_get_int,
		  &nlm_tcpport, 0644);
module_param(nsm_use_hostnames, bool, 0644);
module_param(nlm_max_connections, uint, 0644);

static int lockd_init_net(struct net *net)
{
	struct lockd_net *ln = net_generic(net, lockd_net_id);

	INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
	INIT_LIST_HEAD(&ln->lockd_manager.list);
	ln->lockd_manager.block_opens = false;
	INIT_LIST_HEAD(&ln->nsm_handles);
	return 0;
}

static void lockd_exit_net(struct net *net)
{
	struct lockd_net *ln = net_generic(net, lockd_net_id);

	WARN_ONCE(!list_empty(&ln->lockd_manager.list),
		  "net %x %s: lockd_manager.list is not empty\n",
		  net->ns.inum, __func__);
	WARN_ONCE(!list_empty(&ln->nsm_handles),
		  "net %x %s: nsm_handles list is not empty\n",
		  net->ns.inum, __func__);
	WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
		  "net %x %s: grace_period_end was not cancelled\n",
		  net->ns.inum, __func__);
}

static struct pernet_operations lockd_net_ops = {
	.init = lockd_init_net,
	.exit = lockd_exit_net,
	.id = &lockd_net_id,
	.size = sizeof(struct lockd_net),
};


/*
 * Initialising and terminating the module.
 */

static int __init init_nlm(void)
{
	int err;

#ifdef CONFIG_SYSCTL
	err = -ENOMEM;
	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
	if (nlm_sysctl_table == NULL)
		goto err_sysctl;
#endif
	err = register_pernet_subsys(&lockd_net_ops);
	if (err)
		goto err_pernet;

	err = lockd_create_procfs();
	if (err)
		goto err_procfs;

	return 0;

err_procfs:
	unregister_pernet_subsys(&lockd_net_ops);
err_pernet:
#ifdef CONFIG_SYSCTL
	unregister_sysctl_table(nlm_sysctl_table);
err_sysctl:
#endif
	return err;
}

static void __exit exit_nlm(void)
{
	/* FIXME: delete all NLM clients */
	nlm_shutdown_hosts();
	lockd_remove_procfs();
	unregister_pernet_subsys(&lockd_net_ops);
#ifdef CONFIG_SYSCTL
	unregister_sysctl_table(nlm_sysctl_table);
#endif
}

module_init(init_nlm);
module_exit(exit_nlm);

/**
 * nlmsvc_dispatch - Process an NLM Request
 * @rqstp: incoming request
 * @statp: pointer to location of accept_stat field in RPC Reply buffer
 *
 * Return values:
 *  %0: Processing complete; do not send a Reply
 *  %1: Processing complete; send Reply in rqstp->rq_res
 */
static int nlmsvc_dispatch(struct svc_rqst *rqstp, __be32 *statp)
{
	const struct svc_procedure *procp = rqstp->rq_procinfo;

	svcxdr_init_decode(rqstp);
	if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
		goto out_decode_err;

	*statp = procp->pc_func(rqstp);
	if (*statp == rpc_drop_reply)
		return 0;
	if (*statp != rpc_success)
		return 1;

	svcxdr_init_encode(rqstp);
	if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
		goto out_encode_err;

	return 1;

out_decode_err:
	*statp = rpc_garbage_args;
	return 1;

out_encode_err:
	*statp = rpc_system_err;
	return 1;
}

/*
 * Define NLM program and procedures
 */
static unsigned int nlmsvc_version1_count[17];
static const struct svc_version	nlmsvc_version1 = {
	.vs_vers	= 1,
	.vs_nproc	= 17,
	.vs_proc	= nlmsvc_procedures,
	.vs_count	= nlmsvc_version1_count,
	.vs_dispatch	= nlmsvc_dispatch,
	.vs_xdrsize	= NLMSVC_XDRSIZE,
};
static unsigned int nlmsvc_version3_count[24];
static const struct svc_version	nlmsvc_version3 = {
	.vs_vers	= 3,
	.vs_nproc	= 24,
	.vs_proc	= nlmsvc_procedures,
	.vs_count	= nlmsvc_version3_count,
	.vs_dispatch	= nlmsvc_dispatch,
	.vs_xdrsize	= NLMSVC_XDRSIZE,
};
#ifdef CONFIG_LOCKD_V4
static unsigned int nlmsvc_version4_count[24];
static const struct svc_version	nlmsvc_version4 = {
	.vs_vers	= 4,
	.vs_nproc	= 24,
	.vs_proc	= nlmsvc_procedures4,
	.vs_count	= nlmsvc_version4_count,
	.vs_dispatch	= nlmsvc_dispatch,
	.vs_xdrsize	= NLMSVC_XDRSIZE,
};
#endif
static const struct svc_version *nlmsvc_version[] = {
	[1] = &nlmsvc_version1,
	[3] = &nlmsvc_version3,
#ifdef CONFIG_LOCKD_V4
	[4] = &nlmsvc_version4,
#endif
};

static struct svc_stat		nlmsvc_stats;

#define NLM_NRVERS	ARRAY_SIZE(nlmsvc_version)
static struct svc_program	nlmsvc_program = {
	.pg_prog		= NLM_PROGRAM,		/* program number */
	.pg_nvers		= NLM_NRVERS,		/* number of entries in nlmsvc_version */
	.pg_vers		= nlmsvc_version,	/* version table */
	.pg_name		= "lockd",		/* service name */
	.pg_class		= "nfsd",		/* share authentication with nfsd */
	.pg_stats		= &nlmsvc_stats,	/* stats table */
	.pg_authenticate	= &lockd_authenticate,	/* export authentication */
	.pg_init_request	= svc_generic_init_request,
	.pg_rpcbind_set		= svc_generic_rpcbind_set,
};