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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
49static struct svc_program nlmsvc_program;
50
51const struct nlmsvc_binding *nlmsvc_ops;
52EXPORT_SYMBOL_GPL(nlmsvc_ops);
53
54static DEFINE_MUTEX(nlmsvc_mutex);
55static unsigned int nlmsvc_users;
56static struct task_struct *nlmsvc_task;
57static struct svc_rqst *nlmsvc_rqst;
58unsigned long nlmsvc_timeout;
59
60static atomic_t nlm_ntf_refcnt = ATOMIC_INIT(0);
61static DECLARE_WAIT_QUEUE_HEAD(nlm_ntf_wq);
62
63unsigned int lockd_net_id;
64
65/*
66 * These can be set at insmod time (useful for NFS as root filesystem),
67 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
68 */
69static unsigned long nlm_grace_period;
70static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
71static int nlm_udpport, nlm_tcpport;
72
73/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
74static unsigned int nlm_max_connections = 1024;
75
76/*
77 * Constants needed for the sysctl interface.
78 */
79static const unsigned long nlm_grace_period_min = 0;
80static const unsigned long nlm_grace_period_max = 240;
81static const unsigned long nlm_timeout_min = 3;
82static const unsigned long nlm_timeout_max = 20;
83static const int nlm_port_min = 0, nlm_port_max = 65535;
84
85#ifdef CONFIG_SYSCTL
86static struct ctl_table_header * nlm_sysctl_table;
87#endif
88
89static unsigned long get_lockd_grace_period(void)
90{
91 /* Note: nlm_timeout should always be nonzero */
92 if (nlm_grace_period)
93 return roundup(nlm_grace_period, nlm_timeout) * HZ;
94 else
95 return nlm_timeout * 5 * HZ;
96}
97
98static void grace_ender(struct work_struct *grace)
99{
100 struct delayed_work *dwork = to_delayed_work(grace);
101 struct lockd_net *ln = container_of(dwork, struct lockd_net,
102 grace_period_end);
103
104 locks_end_grace(&ln->lockd_manager);
105}
106
107static void set_grace_period(struct net *net)
108{
109 unsigned long grace_period = get_lockd_grace_period();
110 struct lockd_net *ln = net_generic(net, lockd_net_id);
111
112 locks_start_grace(net, &ln->lockd_manager);
113 cancel_delayed_work_sync(&ln->grace_period_end);
114 schedule_delayed_work(&ln->grace_period_end, grace_period);
115}
116
117static void restart_grace(void)
118{
119 if (nlmsvc_ops) {
120 struct net *net = &init_net;
121 struct lockd_net *ln = net_generic(net, lockd_net_id);
122
123 cancel_delayed_work_sync(&ln->grace_period_end);
124 locks_end_grace(&ln->lockd_manager);
125 nlmsvc_invalidate_all();
126 set_grace_period(net);
127 }
128}
129
130/*
131 * This is the lockd kernel thread
132 */
133static int
134lockd(void *vrqstp)
135{
136 int err = 0;
137 struct svc_rqst *rqstp = vrqstp;
138 struct net *net = &init_net;
139 struct lockd_net *ln = net_generic(net, lockd_net_id);
140
141 /* try_to_freeze() is called from svc_recv() */
142 set_freezable();
143
144 /* Allow SIGKILL to tell lockd to drop all of its locks */
145 allow_signal(SIGKILL);
146
147 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
148
149 /*
150 * The main request loop. We don't terminate until the last
151 * NFS mount or NFS daemon has gone away.
152 */
153 while (!kthread_should_stop()) {
154 long timeout = MAX_SCHEDULE_TIMEOUT;
155 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
156
157 /* update sv_maxconn if it has changed */
158 rqstp->rq_server->sv_maxconn = nlm_max_connections;
159
160 if (signalled()) {
161 flush_signals(current);
162 restart_grace();
163 continue;
164 }
165
166 timeout = nlmsvc_retry_blocked();
167
168 /*
169 * Find a socket with data available and call its
170 * recvfrom routine.
171 */
172 err = svc_recv(rqstp, timeout);
173 if (err == -EAGAIN || err == -EINTR)
174 continue;
175 dprintk("lockd: request from %s\n",
176 svc_print_addr(rqstp, buf, sizeof(buf)));
177
178 svc_process(rqstp);
179 }
180 flush_signals(current);
181 if (nlmsvc_ops)
182 nlmsvc_invalidate_all();
183 nlm_shutdown_hosts();
184 cancel_delayed_work_sync(&ln->grace_period_end);
185 locks_end_grace(&ln->lockd_manager);
186 return 0;
187}
188
189static int create_lockd_listener(struct svc_serv *serv, const char *name,
190 struct net *net, const int family,
191 const unsigned short port)
192{
193 struct svc_xprt *xprt;
194
195 xprt = svc_find_xprt(serv, name, net, family, 0);
196 if (xprt == NULL)
197 return svc_create_xprt(serv, name, net, family, port,
198 SVC_SOCK_DEFAULTS);
199 svc_xprt_put(xprt);
200 return 0;
201}
202
203static int create_lockd_family(struct svc_serv *serv, struct net *net,
204 const int family)
205{
206 int err;
207
208 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
209 if (err < 0)
210 return err;
211
212 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
213}
214
215/*
216 * Ensure there are active UDP and TCP listeners for lockd.
217 *
218 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
219 * local services (such as rpc.statd) still require UDP, and
220 * some NFS servers do not yet support NLM over TCP.
221 *
222 * Returns zero if all listeners are available; otherwise a
223 * negative errno value is returned.
224 */
225static int make_socks(struct svc_serv *serv, struct net *net)
226{
227 static int warned;
228 int err;
229
230 err = create_lockd_family(serv, net, PF_INET);
231 if (err < 0)
232 goto out_err;
233
234 err = create_lockd_family(serv, net, PF_INET6);
235 if (err < 0 && err != -EAFNOSUPPORT)
236 goto out_err;
237
238 warned = 0;
239 return 0;
240
241out_err:
242 if (warned++ == 0)
243 printk(KERN_WARNING
244 "lockd_up: makesock failed, error=%d\n", err);
245 svc_shutdown_net(serv, net);
246 return err;
247}
248
249static int lockd_up_net(struct svc_serv *serv, struct net *net)
250{
251 struct lockd_net *ln = net_generic(net, lockd_net_id);
252 int error;
253
254 if (ln->nlmsvc_users++)
255 return 0;
256
257 error = svc_bind(serv, net);
258 if (error)
259 goto err_bind;
260
261 error = make_socks(serv, net);
262 if (error < 0)
263 goto err_bind;
264 set_grace_period(net);
265 dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
266 return 0;
267
268err_bind:
269 ln->nlmsvc_users--;
270 return error;
271}
272
273static void lockd_down_net(struct svc_serv *serv, struct net *net)
274{
275 struct lockd_net *ln = net_generic(net, lockd_net_id);
276
277 if (ln->nlmsvc_users) {
278 if (--ln->nlmsvc_users == 0) {
279 nlm_shutdown_hosts_net(net);
280 cancel_delayed_work_sync(&ln->grace_period_end);
281 locks_end_grace(&ln->lockd_manager);
282 svc_shutdown_net(serv, net);
283 dprintk("%s: per-net data destroyed; net=%x\n",
284 __func__, net->ns.inum);
285 }
286 } else {
287 pr_err("%s: no users! task=%p, net=%x\n",
288 __func__, nlmsvc_task, net->ns.inum);
289 BUG();
290 }
291}
292
293static int lockd_inetaddr_event(struct notifier_block *this,
294 unsigned long event, void *ptr)
295{
296 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
297 struct sockaddr_in sin;
298
299 if ((event != NETDEV_DOWN) ||
300 !atomic_inc_not_zero(&nlm_ntf_refcnt))
301 goto out;
302
303 if (nlmsvc_rqst) {
304 dprintk("lockd_inetaddr_event: removed %pI4\n",
305 &ifa->ifa_local);
306 sin.sin_family = AF_INET;
307 sin.sin_addr.s_addr = ifa->ifa_local;
308 svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
309 (struct sockaddr *)&sin);
310 }
311 atomic_dec(&nlm_ntf_refcnt);
312 wake_up(&nlm_ntf_wq);
313
314out:
315 return NOTIFY_DONE;
316}
317
318static struct notifier_block lockd_inetaddr_notifier = {
319 .notifier_call = lockd_inetaddr_event,
320};
321
322#if IS_ENABLED(CONFIG_IPV6)
323static int lockd_inet6addr_event(struct notifier_block *this,
324 unsigned long event, void *ptr)
325{
326 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
327 struct sockaddr_in6 sin6;
328
329 if ((event != NETDEV_DOWN) ||
330 !atomic_inc_not_zero(&nlm_ntf_refcnt))
331 goto out;
332
333 if (nlmsvc_rqst) {
334 dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
335 sin6.sin6_family = AF_INET6;
336 sin6.sin6_addr = ifa->addr;
337 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
338 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
339 svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
340 (struct sockaddr *)&sin6);
341 }
342 atomic_dec(&nlm_ntf_refcnt);
343 wake_up(&nlm_ntf_wq);
344
345out:
346 return NOTIFY_DONE;
347}
348
349static struct notifier_block lockd_inet6addr_notifier = {
350 .notifier_call = lockd_inet6addr_event,
351};
352#endif
353
354static void lockd_unregister_notifiers(void)
355{
356 unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
357#if IS_ENABLED(CONFIG_IPV6)
358 unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
359#endif
360 wait_event(nlm_ntf_wq, atomic_read(&nlm_ntf_refcnt) == 0);
361}
362
363static void lockd_svc_exit_thread(void)
364{
365 atomic_dec(&nlm_ntf_refcnt);
366 lockd_unregister_notifiers();
367 svc_exit_thread(nlmsvc_rqst);
368}
369
370static int lockd_start_svc(struct svc_serv *serv)
371{
372 int error;
373
374 if (nlmsvc_rqst)
375 return 0;
376
377 /*
378 * Create the kernel thread and wait for it to start.
379 */
380 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
381 if (IS_ERR(nlmsvc_rqst)) {
382 error = PTR_ERR(nlmsvc_rqst);
383 printk(KERN_WARNING
384 "lockd_up: svc_rqst allocation failed, error=%d\n",
385 error);
386 lockd_unregister_notifiers();
387 goto out_rqst;
388 }
389
390 atomic_inc(&nlm_ntf_refcnt);
391 svc_sock_update_bufs(serv);
392 serv->sv_maxconn = nlm_max_connections;
393
394 nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name);
395 if (IS_ERR(nlmsvc_task)) {
396 error = PTR_ERR(nlmsvc_task);
397 printk(KERN_WARNING
398 "lockd_up: kthread_run failed, error=%d\n", error);
399 goto out_task;
400 }
401 nlmsvc_rqst->rq_task = nlmsvc_task;
402 wake_up_process(nlmsvc_task);
403
404 dprintk("lockd_up: service started\n");
405 return 0;
406
407out_task:
408 lockd_svc_exit_thread();
409 nlmsvc_task = NULL;
410out_rqst:
411 nlmsvc_rqst = NULL;
412 return error;
413}
414
415static const struct svc_serv_ops lockd_sv_ops = {
416 .svo_shutdown = svc_rpcb_cleanup,
417 .svo_enqueue_xprt = svc_xprt_do_enqueue,
418};
419
420static struct svc_serv *lockd_create_svc(void)
421{
422 struct svc_serv *serv;
423
424 /*
425 * Check whether we're already up and running.
426 */
427 if (nlmsvc_rqst) {
428 /*
429 * Note: increase service usage, because later in case of error
430 * svc_destroy() will be called.
431 */
432 svc_get(nlmsvc_rqst->rq_server);
433 return nlmsvc_rqst->rq_server;
434 }
435
436 /*
437 * Sanity check: if there's no pid,
438 * we should be the first user ...
439 */
440 if (nlmsvc_users)
441 printk(KERN_WARNING
442 "lockd_up: no pid, %d users??\n", nlmsvc_users);
443
444 if (!nlm_timeout)
445 nlm_timeout = LOCKD_DFLT_TIMEO;
446 nlmsvc_timeout = nlm_timeout * HZ;
447
448 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
449 if (!serv) {
450 printk(KERN_WARNING "lockd_up: create service failed\n");
451 return ERR_PTR(-ENOMEM);
452 }
453 register_inetaddr_notifier(&lockd_inetaddr_notifier);
454#if IS_ENABLED(CONFIG_IPV6)
455 register_inet6addr_notifier(&lockd_inet6addr_notifier);
456#endif
457 dprintk("lockd_up: service created\n");
458 return serv;
459}
460
461/*
462 * Bring up the lockd process if it's not already up.
463 */
464int lockd_up(struct net *net)
465{
466 struct svc_serv *serv;
467 int error;
468
469 mutex_lock(&nlmsvc_mutex);
470
471 serv = lockd_create_svc();
472 if (IS_ERR(serv)) {
473 error = PTR_ERR(serv);
474 goto err_create;
475 }
476
477 error = lockd_up_net(serv, net);
478 if (error < 0) {
479 lockd_unregister_notifiers();
480 goto err_put;
481 }
482
483 error = lockd_start_svc(serv);
484 if (error < 0) {
485 lockd_down_net(serv, net);
486 goto err_put;
487 }
488 nlmsvc_users++;
489 /*
490 * Note: svc_serv structures have an initial use count of 1,
491 * so we exit through here on both success and failure.
492 */
493err_put:
494 svc_destroy(serv);
495err_create:
496 mutex_unlock(&nlmsvc_mutex);
497 return error;
498}
499EXPORT_SYMBOL_GPL(lockd_up);
500
501/*
502 * Decrement the user count and bring down lockd if we're the last.
503 */
504void
505lockd_down(struct net *net)
506{
507 mutex_lock(&nlmsvc_mutex);
508 lockd_down_net(nlmsvc_rqst->rq_server, net);
509 if (nlmsvc_users) {
510 if (--nlmsvc_users)
511 goto out;
512 } else {
513 printk(KERN_ERR "lockd_down: no users! task=%p\n",
514 nlmsvc_task);
515 BUG();
516 }
517
518 if (!nlmsvc_task) {
519 printk(KERN_ERR "lockd_down: no lockd running.\n");
520 BUG();
521 }
522 kthread_stop(nlmsvc_task);
523 dprintk("lockd_down: service stopped\n");
524 lockd_svc_exit_thread();
525 dprintk("lockd_down: service destroyed\n");
526 nlmsvc_task = NULL;
527 nlmsvc_rqst = NULL;
528out:
529 mutex_unlock(&nlmsvc_mutex);
530}
531EXPORT_SYMBOL_GPL(lockd_down);
532
533#ifdef CONFIG_SYSCTL
534
535/*
536 * Sysctl parameters (same as module parameters, different interface).
537 */
538
539static struct ctl_table nlm_sysctls[] = {
540 {
541 .procname = "nlm_grace_period",
542 .data = &nlm_grace_period,
543 .maxlen = sizeof(unsigned long),
544 .mode = 0644,
545 .proc_handler = proc_doulongvec_minmax,
546 .extra1 = (unsigned long *) &nlm_grace_period_min,
547 .extra2 = (unsigned long *) &nlm_grace_period_max,
548 },
549 {
550 .procname = "nlm_timeout",
551 .data = &nlm_timeout,
552 .maxlen = sizeof(unsigned long),
553 .mode = 0644,
554 .proc_handler = proc_doulongvec_minmax,
555 .extra1 = (unsigned long *) &nlm_timeout_min,
556 .extra2 = (unsigned long *) &nlm_timeout_max,
557 },
558 {
559 .procname = "nlm_udpport",
560 .data = &nlm_udpport,
561 .maxlen = sizeof(int),
562 .mode = 0644,
563 .proc_handler = proc_dointvec_minmax,
564 .extra1 = (int *) &nlm_port_min,
565 .extra2 = (int *) &nlm_port_max,
566 },
567 {
568 .procname = "nlm_tcpport",
569 .data = &nlm_tcpport,
570 .maxlen = sizeof(int),
571 .mode = 0644,
572 .proc_handler = proc_dointvec_minmax,
573 .extra1 = (int *) &nlm_port_min,
574 .extra2 = (int *) &nlm_port_max,
575 },
576 {
577 .procname = "nsm_use_hostnames",
578 .data = &nsm_use_hostnames,
579 .maxlen = sizeof(int),
580 .mode = 0644,
581 .proc_handler = proc_dointvec,
582 },
583 {
584 .procname = "nsm_local_state",
585 .data = &nsm_local_state,
586 .maxlen = sizeof(int),
587 .mode = 0644,
588 .proc_handler = proc_dointvec,
589 },
590 { }
591};
592
593static struct ctl_table nlm_sysctl_dir[] = {
594 {
595 .procname = "nfs",
596 .mode = 0555,
597 .child = nlm_sysctls,
598 },
599 { }
600};
601
602static struct ctl_table nlm_sysctl_root[] = {
603 {
604 .procname = "fs",
605 .mode = 0555,
606 .child = nlm_sysctl_dir,
607 },
608 { }
609};
610
611#endif /* CONFIG_SYSCTL */
612
613/*
614 * Module (and sysfs) parameters.
615 */
616
617#define param_set_min_max(name, type, which_strtol, min, max) \
618static int param_set_##name(const char *val, const struct kernel_param *kp) \
619{ \
620 char *endp; \
621 __typeof__(type) num = which_strtol(val, &endp, 0); \
622 if (endp == val || *endp || num < (min) || num > (max)) \
623 return -EINVAL; \
624 *((type *) kp->arg) = num; \
625 return 0; \
626}
627
628static inline int is_callback(u32 proc)
629{
630 return proc == NLMPROC_GRANTED
631 || proc == NLMPROC_GRANTED_MSG
632 || proc == NLMPROC_TEST_RES
633 || proc == NLMPROC_LOCK_RES
634 || proc == NLMPROC_CANCEL_RES
635 || proc == NLMPROC_UNLOCK_RES
636 || proc == NLMPROC_NSM_NOTIFY;
637}
638
639
640static int lockd_authenticate(struct svc_rqst *rqstp)
641{
642 rqstp->rq_client = NULL;
643 switch (rqstp->rq_authop->flavour) {
644 case RPC_AUTH_NULL:
645 case RPC_AUTH_UNIX:
646 if (rqstp->rq_proc == 0)
647 return SVC_OK;
648 if (is_callback(rqstp->rq_proc)) {
649 /* Leave it to individual procedures to
650 * call nlmsvc_lookup_host(rqstp)
651 */
652 return SVC_OK;
653 }
654 return svc_set_client(rqstp);
655 }
656 return SVC_DENIED;
657}
658
659
660param_set_min_max(port, int, simple_strtol, 0, 65535)
661param_set_min_max(grace_period, unsigned long, simple_strtoul,
662 nlm_grace_period_min, nlm_grace_period_max)
663param_set_min_max(timeout, unsigned long, simple_strtoul,
664 nlm_timeout_min, nlm_timeout_max)
665
666MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
667MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
668MODULE_LICENSE("GPL");
669
670module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
671 &nlm_grace_period, 0644);
672module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
673 &nlm_timeout, 0644);
674module_param_call(nlm_udpport, param_set_port, param_get_int,
675 &nlm_udpport, 0644);
676module_param_call(nlm_tcpport, param_set_port, param_get_int,
677 &nlm_tcpport, 0644);
678module_param(nsm_use_hostnames, bool, 0644);
679module_param(nlm_max_connections, uint, 0644);
680
681static int lockd_init_net(struct net *net)
682{
683 struct lockd_net *ln = net_generic(net, lockd_net_id);
684
685 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
686 INIT_LIST_HEAD(&ln->lockd_manager.list);
687 ln->lockd_manager.block_opens = false;
688 INIT_LIST_HEAD(&ln->nsm_handles);
689 return 0;
690}
691
692static void lockd_exit_net(struct net *net)
693{
694 struct lockd_net *ln = net_generic(net, lockd_net_id);
695
696 WARN_ONCE(!list_empty(&ln->lockd_manager.list),
697 "net %x %s: lockd_manager.list is not empty\n",
698 net->ns.inum, __func__);
699 WARN_ONCE(!list_empty(&ln->nsm_handles),
700 "net %x %s: nsm_handles list is not empty\n",
701 net->ns.inum, __func__);
702 WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
703 "net %x %s: grace_period_end was not cancelled\n",
704 net->ns.inum, __func__);
705}
706
707static struct pernet_operations lockd_net_ops = {
708 .init = lockd_init_net,
709 .exit = lockd_exit_net,
710 .id = &lockd_net_id,
711 .size = sizeof(struct lockd_net),
712};
713
714
715/*
716 * Initialising and terminating the module.
717 */
718
719static int __init init_nlm(void)
720{
721 int err;
722
723#ifdef CONFIG_SYSCTL
724 err = -ENOMEM;
725 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
726 if (nlm_sysctl_table == NULL)
727 goto err_sysctl;
728#endif
729 err = register_pernet_subsys(&lockd_net_ops);
730 if (err)
731 goto err_pernet;
732
733 err = lockd_create_procfs();
734 if (err)
735 goto err_procfs;
736
737 return 0;
738
739err_procfs:
740 unregister_pernet_subsys(&lockd_net_ops);
741err_pernet:
742#ifdef CONFIG_SYSCTL
743 unregister_sysctl_table(nlm_sysctl_table);
744err_sysctl:
745#endif
746 return err;
747}
748
749static void __exit exit_nlm(void)
750{
751 /* FIXME: delete all NLM clients */
752 nlm_shutdown_hosts();
753 lockd_remove_procfs();
754 unregister_pernet_subsys(&lockd_net_ops);
755#ifdef CONFIG_SYSCTL
756 unregister_sysctl_table(nlm_sysctl_table);
757#endif
758}
759
760module_init(init_nlm);
761module_exit(exit_nlm);
762
763/*
764 * Define NLM program and procedures
765 */
766static unsigned int nlmsvc_version1_count[17];
767static const struct svc_version nlmsvc_version1 = {
768 .vs_vers = 1,
769 .vs_nproc = 17,
770 .vs_proc = nlmsvc_procedures,
771 .vs_count = nlmsvc_version1_count,
772 .vs_xdrsize = NLMSVC_XDRSIZE,
773};
774static unsigned int nlmsvc_version3_count[24];
775static const struct svc_version nlmsvc_version3 = {
776 .vs_vers = 3,
777 .vs_nproc = 24,
778 .vs_proc = nlmsvc_procedures,
779 .vs_count = nlmsvc_version3_count,
780 .vs_xdrsize = NLMSVC_XDRSIZE,
781};
782#ifdef CONFIG_LOCKD_V4
783static unsigned int nlmsvc_version4_count[24];
784static const struct svc_version nlmsvc_version4 = {
785 .vs_vers = 4,
786 .vs_nproc = 24,
787 .vs_proc = nlmsvc_procedures4,
788 .vs_count = nlmsvc_version4_count,
789 .vs_xdrsize = NLMSVC_XDRSIZE,
790};
791#endif
792static const struct svc_version *nlmsvc_version[] = {
793 [1] = &nlmsvc_version1,
794 [3] = &nlmsvc_version3,
795#ifdef CONFIG_LOCKD_V4
796 [4] = &nlmsvc_version4,
797#endif
798};
799
800static struct svc_stat nlmsvc_stats;
801
802#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
803static struct svc_program nlmsvc_program = {
804 .pg_prog = NLM_PROGRAM, /* program number */
805 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
806 .pg_vers = nlmsvc_version, /* version table */
807 .pg_name = "lockd", /* service name */
808 .pg_class = "nfsd", /* share authentication with nfsd */
809 .pg_stats = &nlmsvc_stats, /* stats table */
810 .pg_authenticate = &lockd_authenticate /* export authentication */
811};
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
44static struct svc_program nlmsvc_program;
45
46struct nlmsvc_binding * nlmsvc_ops;
47EXPORT_SYMBOL_GPL(nlmsvc_ops);
48
49static DEFINE_MUTEX(nlmsvc_mutex);
50static unsigned int nlmsvc_users;
51static struct task_struct *nlmsvc_task;
52static struct svc_rqst *nlmsvc_rqst;
53unsigned long nlmsvc_timeout;
54
55int 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 */
61static unsigned long nlm_grace_period;
62static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
63static int nlm_udpport, nlm_tcpport;
64
65/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
66static unsigned int nlm_max_connections = 1024;
67
68/*
69 * Constants needed for the sysctl interface.
70 */
71static const unsigned long nlm_grace_period_min = 0;
72static const unsigned long nlm_grace_period_max = 240;
73static const unsigned long nlm_timeout_min = 3;
74static const unsigned long nlm_timeout_max = 20;
75static const int nlm_port_min = 0, nlm_port_max = 65535;
76
77#ifdef CONFIG_SYSCTL
78static struct ctl_table_header * nlm_sysctl_table;
79#endif
80
81static 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
90static struct lock_manager lockd_manager = {
91};
92
93static void grace_ender(struct work_struct *not_used)
94{
95 locks_end_grace(&lockd_manager);
96}
97
98static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
99
100static void set_grace_period(void)
101{
102 unsigned long grace_period = get_lockd_grace_period();
103
104 locks_start_grace(&lockd_manager);
105 cancel_delayed_work_sync(&grace_period_end);
106 schedule_delayed_work(&grace_period_end, grace_period);
107}
108
109static void restart_grace(void)
110{
111 if (nlmsvc_ops) {
112 cancel_delayed_work_sync(&grace_period_end);
113 locks_end_grace(&lockd_manager);
114 nlmsvc_invalidate_all();
115 set_grace_period();
116 }
117}
118
119/*
120 * This is the lockd kernel thread
121 */
122static int
123lockd(void *vrqstp)
124{
125 int err = 0, preverr = 0;
126 struct svc_rqst *rqstp = vrqstp;
127
128 /* try_to_freeze() is called from svc_recv() */
129 set_freezable();
130
131 /* Allow SIGKILL to tell lockd to drop all of its locks */
132 allow_signal(SIGKILL);
133
134 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
135
136 if (!nlm_timeout)
137 nlm_timeout = LOCKD_DFLT_TIMEO;
138 nlmsvc_timeout = nlm_timeout * HZ;
139
140 set_grace_period();
141
142 /*
143 * The main request loop. We don't terminate until the last
144 * NFS mount or NFS daemon has gone away.
145 */
146 while (!kthread_should_stop()) {
147 long timeout = MAX_SCHEDULE_TIMEOUT;
148 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
149
150 /* update sv_maxconn if it has changed */
151 rqstp->rq_server->sv_maxconn = nlm_max_connections;
152
153 if (signalled()) {
154 flush_signals(current);
155 restart_grace();
156 continue;
157 }
158
159 timeout = nlmsvc_retry_blocked();
160
161 /*
162 * Find a socket with data available and call its
163 * recvfrom routine.
164 */
165 err = svc_recv(rqstp, timeout);
166 if (err == -EAGAIN || err == -EINTR) {
167 preverr = err;
168 continue;
169 }
170 if (err < 0) {
171 if (err != preverr) {
172 printk(KERN_WARNING "%s: unexpected error "
173 "from svc_recv (%d)\n", __func__, err);
174 preverr = err;
175 }
176 schedule_timeout_interruptible(HZ);
177 continue;
178 }
179 preverr = err;
180
181 dprintk("lockd: request from %s\n",
182 svc_print_addr(rqstp, buf, sizeof(buf)));
183
184 svc_process(rqstp);
185 }
186 flush_signals(current);
187 cancel_delayed_work_sync(&grace_period_end);
188 locks_end_grace(&lockd_manager);
189 if (nlmsvc_ops)
190 nlmsvc_invalidate_all();
191 nlm_shutdown_hosts();
192 return 0;
193}
194
195static int create_lockd_listener(struct svc_serv *serv, const char *name,
196 struct net *net, const int family,
197 const unsigned short port)
198{
199 struct svc_xprt *xprt;
200
201 xprt = svc_find_xprt(serv, name, net, family, 0);
202 if (xprt == NULL)
203 return svc_create_xprt(serv, name, net, family, port,
204 SVC_SOCK_DEFAULTS);
205 svc_xprt_put(xprt);
206 return 0;
207}
208
209static int create_lockd_family(struct svc_serv *serv, struct net *net,
210 const int family)
211{
212 int err;
213
214 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport);
215 if (err < 0)
216 return err;
217
218 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport);
219}
220
221/*
222 * Ensure there are active UDP and TCP listeners for lockd.
223 *
224 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
225 * local services (such as rpc.statd) still require UDP, and
226 * some NFS servers do not yet support NLM over TCP.
227 *
228 * Returns zero if all listeners are available; otherwise a
229 * negative errno value is returned.
230 */
231static int make_socks(struct svc_serv *serv, struct net *net)
232{
233 static int warned;
234 int err;
235
236 err = create_lockd_family(serv, net, PF_INET);
237 if (err < 0)
238 goto out_err;
239
240 err = create_lockd_family(serv, net, PF_INET6);
241 if (err < 0 && err != -EAFNOSUPPORT)
242 goto out_err;
243
244 warned = 0;
245 return 0;
246
247out_err:
248 if (warned++ == 0)
249 printk(KERN_WARNING
250 "lockd_up: makesock failed, error=%d\n", err);
251 return err;
252}
253
254static int lockd_up_net(struct svc_serv *serv, struct net *net)
255{
256 struct lockd_net *ln = net_generic(net, lockd_net_id);
257 int error;
258
259 if (ln->nlmsvc_users++)
260 return 0;
261
262 error = svc_bind(serv, net);
263 if (error)
264 goto err_bind;
265
266 error = make_socks(serv, net);
267 if (error < 0)
268 goto err_socks;
269 dprintk("lockd_up_net: per-net data created; net=%p\n", net);
270 return 0;
271
272err_socks:
273 svc_rpcb_cleanup(serv, net);
274err_bind:
275 ln->nlmsvc_users--;
276 return error;
277}
278
279static void lockd_down_net(struct svc_serv *serv, struct net *net)
280{
281 struct lockd_net *ln = net_generic(net, lockd_net_id);
282
283 if (ln->nlmsvc_users) {
284 if (--ln->nlmsvc_users == 0) {
285 nlm_shutdown_hosts_net(net);
286 svc_shutdown_net(serv, net);
287 dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net);
288 }
289 } else {
290 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n",
291 nlmsvc_task, net);
292 BUG();
293 }
294}
295
296static int lockd_start_svc(struct svc_serv *serv)
297{
298 int error;
299
300 if (nlmsvc_rqst)
301 return 0;
302
303 /*
304 * Create the kernel thread and wait for it to start.
305 */
306 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
307 if (IS_ERR(nlmsvc_rqst)) {
308 error = PTR_ERR(nlmsvc_rqst);
309 printk(KERN_WARNING
310 "lockd_up: svc_rqst allocation failed, error=%d\n",
311 error);
312 goto out_rqst;
313 }
314
315 svc_sock_update_bufs(serv);
316 serv->sv_maxconn = nlm_max_connections;
317
318 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
319 if (IS_ERR(nlmsvc_task)) {
320 error = PTR_ERR(nlmsvc_task);
321 printk(KERN_WARNING
322 "lockd_up: kthread_run failed, error=%d\n", error);
323 goto out_task;
324 }
325 dprintk("lockd_up: service started\n");
326 return 0;
327
328out_task:
329 svc_exit_thread(nlmsvc_rqst);
330 nlmsvc_task = NULL;
331out_rqst:
332 nlmsvc_rqst = NULL;
333 return error;
334}
335
336static struct svc_serv *lockd_create_svc(void)
337{
338 struct svc_serv *serv;
339
340 /*
341 * Check whether we're already up and running.
342 */
343 if (nlmsvc_rqst) {
344 /*
345 * Note: increase service usage, because later in case of error
346 * svc_destroy() will be called.
347 */
348 svc_get(nlmsvc_rqst->rq_server);
349 return nlmsvc_rqst->rq_server;
350 }
351
352 /*
353 * Sanity check: if there's no pid,
354 * we should be the first user ...
355 */
356 if (nlmsvc_users)
357 printk(KERN_WARNING
358 "lockd_up: no pid, %d users??\n", nlmsvc_users);
359
360 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
361 if (!serv) {
362 printk(KERN_WARNING "lockd_up: create service failed\n");
363 return ERR_PTR(-ENOMEM);
364 }
365 dprintk("lockd_up: service created\n");
366 return serv;
367}
368
369/*
370 * Bring up the lockd process if it's not already up.
371 */
372int lockd_up(struct net *net)
373{
374 struct svc_serv *serv;
375 int error;
376
377 mutex_lock(&nlmsvc_mutex);
378
379 serv = lockd_create_svc();
380 if (IS_ERR(serv)) {
381 error = PTR_ERR(serv);
382 goto err_create;
383 }
384
385 error = lockd_up_net(serv, net);
386 if (error < 0)
387 goto err_net;
388
389 error = lockd_start_svc(serv);
390 if (error < 0)
391 goto err_start;
392
393 nlmsvc_users++;
394 /*
395 * Note: svc_serv structures have an initial use count of 1,
396 * so we exit through here on both success and failure.
397 */
398err_net:
399 svc_destroy(serv);
400err_create:
401 mutex_unlock(&nlmsvc_mutex);
402 return error;
403
404err_start:
405 lockd_down_net(serv, net);
406 goto err_net;
407}
408EXPORT_SYMBOL_GPL(lockd_up);
409
410/*
411 * Decrement the user count and bring down lockd if we're the last.
412 */
413void
414lockd_down(struct net *net)
415{
416 mutex_lock(&nlmsvc_mutex);
417 lockd_down_net(nlmsvc_rqst->rq_server, net);
418 if (nlmsvc_users) {
419 if (--nlmsvc_users)
420 goto out;
421 } else {
422 printk(KERN_ERR "lockd_down: no users! task=%p\n",
423 nlmsvc_task);
424 BUG();
425 }
426
427 if (!nlmsvc_task) {
428 printk(KERN_ERR "lockd_down: no lockd running.\n");
429 BUG();
430 }
431 kthread_stop(nlmsvc_task);
432 dprintk("lockd_down: service stopped\n");
433 svc_exit_thread(nlmsvc_rqst);
434 dprintk("lockd_down: service destroyed\n");
435 nlmsvc_task = NULL;
436 nlmsvc_rqst = NULL;
437out:
438 mutex_unlock(&nlmsvc_mutex);
439}
440EXPORT_SYMBOL_GPL(lockd_down);
441
442#ifdef CONFIG_SYSCTL
443
444/*
445 * Sysctl parameters (same as module parameters, different interface).
446 */
447
448static ctl_table nlm_sysctls[] = {
449 {
450 .procname = "nlm_grace_period",
451 .data = &nlm_grace_period,
452 .maxlen = sizeof(unsigned long),
453 .mode = 0644,
454 .proc_handler = proc_doulongvec_minmax,
455 .extra1 = (unsigned long *) &nlm_grace_period_min,
456 .extra2 = (unsigned long *) &nlm_grace_period_max,
457 },
458 {
459 .procname = "nlm_timeout",
460 .data = &nlm_timeout,
461 .maxlen = sizeof(unsigned long),
462 .mode = 0644,
463 .proc_handler = proc_doulongvec_minmax,
464 .extra1 = (unsigned long *) &nlm_timeout_min,
465 .extra2 = (unsigned long *) &nlm_timeout_max,
466 },
467 {
468 .procname = "nlm_udpport",
469 .data = &nlm_udpport,
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 = "nlm_tcpport",
478 .data = &nlm_tcpport,
479 .maxlen = sizeof(int),
480 .mode = 0644,
481 .proc_handler = proc_dointvec_minmax,
482 .extra1 = (int *) &nlm_port_min,
483 .extra2 = (int *) &nlm_port_max,
484 },
485 {
486 .procname = "nsm_use_hostnames",
487 .data = &nsm_use_hostnames,
488 .maxlen = sizeof(int),
489 .mode = 0644,
490 .proc_handler = proc_dointvec,
491 },
492 {
493 .procname = "nsm_local_state",
494 .data = &nsm_local_state,
495 .maxlen = sizeof(int),
496 .mode = 0644,
497 .proc_handler = proc_dointvec,
498 },
499 { }
500};
501
502static ctl_table nlm_sysctl_dir[] = {
503 {
504 .procname = "nfs",
505 .mode = 0555,
506 .child = nlm_sysctls,
507 },
508 { }
509};
510
511static ctl_table nlm_sysctl_root[] = {
512 {
513 .procname = "fs",
514 .mode = 0555,
515 .child = nlm_sysctl_dir,
516 },
517 { }
518};
519
520#endif /* CONFIG_SYSCTL */
521
522/*
523 * Module (and sysfs) parameters.
524 */
525
526#define param_set_min_max(name, type, which_strtol, min, max) \
527static int param_set_##name(const char *val, struct kernel_param *kp) \
528{ \
529 char *endp; \
530 __typeof__(type) num = which_strtol(val, &endp, 0); \
531 if (endp == val || *endp || num < (min) || num > (max)) \
532 return -EINVAL; \
533 *((type *) kp->arg) = num; \
534 return 0; \
535}
536
537static inline int is_callback(u32 proc)
538{
539 return proc == NLMPROC_GRANTED
540 || proc == NLMPROC_GRANTED_MSG
541 || proc == NLMPROC_TEST_RES
542 || proc == NLMPROC_LOCK_RES
543 || proc == NLMPROC_CANCEL_RES
544 || proc == NLMPROC_UNLOCK_RES
545 || proc == NLMPROC_NSM_NOTIFY;
546}
547
548
549static int lockd_authenticate(struct svc_rqst *rqstp)
550{
551 rqstp->rq_client = NULL;
552 switch (rqstp->rq_authop->flavour) {
553 case RPC_AUTH_NULL:
554 case RPC_AUTH_UNIX:
555 if (rqstp->rq_proc == 0)
556 return SVC_OK;
557 if (is_callback(rqstp->rq_proc)) {
558 /* Leave it to individual procedures to
559 * call nlmsvc_lookup_host(rqstp)
560 */
561 return SVC_OK;
562 }
563 return svc_set_client(rqstp);
564 }
565 return SVC_DENIED;
566}
567
568
569param_set_min_max(port, int, simple_strtol, 0, 65535)
570param_set_min_max(grace_period, unsigned long, simple_strtoul,
571 nlm_grace_period_min, nlm_grace_period_max)
572param_set_min_max(timeout, unsigned long, simple_strtoul,
573 nlm_timeout_min, nlm_timeout_max)
574
575MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
576MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
577MODULE_LICENSE("GPL");
578
579module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
580 &nlm_grace_period, 0644);
581module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
582 &nlm_timeout, 0644);
583module_param_call(nlm_udpport, param_set_port, param_get_int,
584 &nlm_udpport, 0644);
585module_param_call(nlm_tcpport, param_set_port, param_get_int,
586 &nlm_tcpport, 0644);
587module_param(nsm_use_hostnames, bool, 0644);
588module_param(nlm_max_connections, uint, 0644);
589
590static int lockd_init_net(struct net *net)
591{
592 return 0;
593}
594
595static void lockd_exit_net(struct net *net)
596{
597}
598
599static struct pernet_operations lockd_net_ops = {
600 .init = lockd_init_net,
601 .exit = lockd_exit_net,
602 .id = &lockd_net_id,
603 .size = sizeof(struct lockd_net),
604};
605
606
607/*
608 * Initialising and terminating the module.
609 */
610
611static int __init init_nlm(void)
612{
613 int err;
614
615#ifdef CONFIG_SYSCTL
616 err = -ENOMEM;
617 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
618 if (nlm_sysctl_table == NULL)
619 goto err_sysctl;
620#endif
621 err = register_pernet_subsys(&lockd_net_ops);
622 if (err)
623 goto err_pernet;
624 return 0;
625
626err_pernet:
627#ifdef CONFIG_SYSCTL
628 unregister_sysctl_table(nlm_sysctl_table);
629#endif
630err_sysctl:
631 return err;
632}
633
634static void __exit exit_nlm(void)
635{
636 /* FIXME: delete all NLM clients */
637 nlm_shutdown_hosts();
638 unregister_pernet_subsys(&lockd_net_ops);
639#ifdef CONFIG_SYSCTL
640 unregister_sysctl_table(nlm_sysctl_table);
641#endif
642}
643
644module_init(init_nlm);
645module_exit(exit_nlm);
646
647/*
648 * Define NLM program and procedures
649 */
650static struct svc_version nlmsvc_version1 = {
651 .vs_vers = 1,
652 .vs_nproc = 17,
653 .vs_proc = nlmsvc_procedures,
654 .vs_xdrsize = NLMSVC_XDRSIZE,
655};
656static struct svc_version nlmsvc_version3 = {
657 .vs_vers = 3,
658 .vs_nproc = 24,
659 .vs_proc = nlmsvc_procedures,
660 .vs_xdrsize = NLMSVC_XDRSIZE,
661};
662#ifdef CONFIG_LOCKD_V4
663static struct svc_version nlmsvc_version4 = {
664 .vs_vers = 4,
665 .vs_nproc = 24,
666 .vs_proc = nlmsvc_procedures4,
667 .vs_xdrsize = NLMSVC_XDRSIZE,
668};
669#endif
670static struct svc_version * nlmsvc_version[] = {
671 [1] = &nlmsvc_version1,
672 [3] = &nlmsvc_version3,
673#ifdef CONFIG_LOCKD_V4
674 [4] = &nlmsvc_version4,
675#endif
676};
677
678static struct svc_stat nlmsvc_stats;
679
680#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
681static struct svc_program nlmsvc_program = {
682 .pg_prog = NLM_PROGRAM, /* program number */
683 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
684 .pg_vers = nlmsvc_version, /* version table */
685 .pg_name = "lockd", /* service name */
686 .pg_class = "nfsd", /* share authentication with nfsd */
687 .pg_stats = &nlmsvc_stats, /* stats table */
688 .pg_authenticate = &lockd_authenticate /* export authentication */
689};