blob: f0791cff45ac6cfc0dbe6a47e21ee70edbac9bdc [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#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/slab.h>
25#include <linux/smp.h>
26#include <linux/smp_lock.h>
Ingo Molnar353ab6e2006-03-26 01:37:12 -080027#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
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>
NeilBrown24e36662006-10-02 02:17:45 -070034#include <net/ip.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <linux/lockd/lockd.h>
36#include <linux/nfs.h>
37
38#define NLMDBG_FACILITY NLMDBG_SVC
39#define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
40#define ALLOWED_SIGS (sigmask(SIGKILL))
41
42static struct svc_program nlmsvc_program;
43
44struct nlmsvc_binding * nlmsvc_ops;
45EXPORT_SYMBOL(nlmsvc_ops);
46
Ingo Molnar353ab6e2006-03-26 01:37:12 -080047static DEFINE_MUTEX(nlmsvc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070048static unsigned int nlmsvc_users;
49static pid_t nlmsvc_pid;
NeilBrown24e36662006-10-02 02:17:45 -070050static struct svc_serv *nlmsvc_serv;
Linus Torvalds1da177e2005-04-16 15:20:36 -070051int nlmsvc_grace_period;
52unsigned long nlmsvc_timeout;
53
Ingo Molnar353ab6e2006-03-26 01:37:12 -080054static DECLARE_COMPLETION(lockd_start_done);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
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/*
66 * Constants needed for the sysctl interface.
67 */
68static const unsigned long nlm_grace_period_min = 0;
69static const unsigned long nlm_grace_period_max = 240;
70static const unsigned long nlm_timeout_min = 3;
71static const unsigned long nlm_timeout_max = 20;
72static const int nlm_port_min = 0, nlm_port_max = 65535;
73
74static struct ctl_table_header * nlm_sysctl_table;
75
76static unsigned long set_grace_period(void)
77{
78 unsigned long grace_period;
79
80 /* Note: nlm_timeout should always be nonzero */
81 if (nlm_grace_period)
82 grace_period = ((nlm_grace_period + nlm_timeout - 1)
83 / nlm_timeout) * nlm_timeout * HZ;
84 else
85 grace_period = nlm_timeout * 5 * HZ;
86 nlmsvc_grace_period = 1;
87 return grace_period + jiffies;
88}
89
90static inline void clear_grace_period(void)
91{
92 nlmsvc_grace_period = 0;
93}
94
95/*
96 * This is the lockd kernel thread
97 */
98static void
99lockd(struct svc_rqst *rqstp)
100{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101 int err = 0;
102 unsigned long grace_period_expire;
103
104 /* Lock module and set up kernel thread */
105 /* lockd_up is waiting for us to startup, so will
106 * be holding a reference to this module, so it
107 * is safe to just claim another reference
108 */
109 __module_get(THIS_MODULE);
110 lock_kernel();
111
112 /*
113 * Let our maker know we're running.
114 */
115 nlmsvc_pid = current->pid;
NeilBrown6fb2b472006-10-02 02:17:50 -0700116 nlmsvc_serv = rqstp->rq_server;
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800117 complete(&lockd_start_done);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
119 daemonize("lockd");
120
121 /* Process request with signals blocked, but allow SIGKILL. */
122 allow_signal(SIGKILL);
123
124 /* kick rpciod */
125 rpciod_up();
126
127 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
128
129 if (!nlm_timeout)
130 nlm_timeout = LOCKD_DFLT_TIMEO;
131 nlmsvc_timeout = nlm_timeout * HZ;
132
133 grace_period_expire = set_grace_period();
134
135 /*
136 * The main request loop. We don't terminate until the last
137 * NFS mount or NFS daemon has gone away, and we've been sent a
138 * signal, or else another process has taken over our job.
139 */
140 while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
141 long timeout = MAX_SCHEDULE_TIMEOUT;
142
143 if (signalled()) {
144 flush_signals(current);
145 if (nlmsvc_ops) {
146 nlmsvc_invalidate_all();
147 grace_period_expire = set_grace_period();
148 }
149 }
150
151 /*
152 * Retry any blocked locks that have been notified by
153 * the VFS. Don't do this during grace period.
154 * (Theoretically, there shouldn't even be blocked locks
155 * during grace period).
156 */
157 if (!nlmsvc_grace_period) {
158 timeout = nlmsvc_retry_blocked();
159 } else if (time_before(grace_period_expire, jiffies))
160 clear_grace_period();
161
162 /*
163 * Find a socket with data available and call its
164 * recvfrom routine.
165 */
NeilBrown6fb2b472006-10-02 02:17:50 -0700166 err = svc_recv(rqstp, timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 if (err == -EAGAIN || err == -EINTR)
168 continue;
169 if (err < 0) {
170 printk(KERN_WARNING
171 "lockd: terminating on error %d\n",
172 -err);
173 break;
174 }
175
176 dprintk("lockd: request from %08x\n",
177 (unsigned)ntohl(rqstp->rq_addr.sin_addr.s_addr));
178
NeilBrown6fb2b472006-10-02 02:17:50 -0700179 svc_process(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
181 }
182
Trond Myklebust2bd61572006-01-03 09:55:19 +0100183 flush_signals(current);
184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 /*
186 * Check whether there's a new lockd process before
187 * shutting down the hosts and clearing the slot.
188 */
189 if (!nlmsvc_pid || current->pid == nlmsvc_pid) {
190 if (nlmsvc_ops)
191 nlmsvc_invalidate_all();
192 nlm_shutdown_hosts();
193 nlmsvc_pid = 0;
NeilBrown24e36662006-10-02 02:17:45 -0700194 nlmsvc_serv = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 } else
196 printk(KERN_DEBUG
197 "lockd: new process, skipping host shutdown\n");
198 wake_up(&lockd_exit);
NeilBrown46be9252005-06-23 22:03:11 -0700199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 /* Exit the RPC thread */
201 svc_exit_thread(rqstp);
202
203 /* release rpciod */
204 rpciod_down();
205
206 /* Release module */
207 unlock_kernel();
208 module_put_and_exit(0);
209}
210
NeilBrown24e36662006-10-02 02:17:45 -0700211
212static int find_socket(struct svc_serv *serv, int proto)
213{
214 struct svc_sock *svsk;
215 int found = 0;
216 list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
217 if (svsk->sk_sk->sk_protocol == proto) {
218 found = 1;
219 break;
220 }
221 return found;
222}
223
224static int make_socks(struct svc_serv *serv, int proto)
225{
226 /* Make any sockets that are needed but not present.
227 * If nlm_udpport or nlm_tcpport were set as module
228 * options, make those sockets unconditionally
229 */
230 int err = 0;
231 if (proto == IPPROTO_UDP || nlm_udpport)
232 if (!find_socket(serv, IPPROTO_UDP))
233 err = svc_makesock(serv, IPPROTO_UDP, nlm_udpport);
234 if (err)
235 return err;
236 if (proto == IPPROTO_TCP || nlm_tcpport)
237 if (!find_socket(serv, IPPROTO_TCP))
238 err= svc_makesock(serv, IPPROTO_TCP, nlm_tcpport);
239 return err;
240}
241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242/*
243 * Bring up the lockd process if it's not already up.
244 */
245int
NeilBrown24e36662006-10-02 02:17:45 -0700246lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247{
248 static int warned;
249 struct svc_serv * serv;
250 int error = 0;
251
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800252 mutex_lock(&nlmsvc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 /*
254 * Unconditionally increment the user count ... this is
255 * the number of clients who _want_ a lockd process.
256 */
257 nlmsvc_users++;
258 /*
259 * Check whether we're already up and running.
260 */
NeilBrown24e36662006-10-02 02:17:45 -0700261 if (nlmsvc_pid) {
262 error = make_socks(nlmsvc_serv, proto);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 goto out;
NeilBrown24e36662006-10-02 02:17:45 -0700264 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265
266 /*
267 * Sanity check: if there's no pid,
268 * we should be the first user ...
269 */
270 if (nlmsvc_users > 1)
271 printk(KERN_WARNING
272 "lockd_up: no pid, %d users??\n", nlmsvc_users);
273
274 error = -ENOMEM;
NeilBrownbc591cc2006-10-02 02:17:44 -0700275 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 if (!serv) {
277 printk(KERN_WARNING "lockd_up: create service failed\n");
278 goto out;
279 }
280
NeilBrown24e36662006-10-02 02:17:45 -0700281 if ((error = make_socks(serv, proto)) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 if (warned++ == 0)
283 printk(KERN_WARNING
284 "lockd_up: makesock failed, error=%d\n", error);
285 goto destroy_and_out;
286 }
287 warned = 0;
288
289 /*
290 * Create the kernel thread and wait for it to start.
291 */
292 error = svc_create_thread(lockd, serv);
293 if (error) {
294 printk(KERN_WARNING
295 "lockd_up: create thread failed, error=%d\n", error);
296 goto destroy_and_out;
297 }
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800298 wait_for_completion(&lockd_start_done);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
300 /*
301 * Note: svc_serv structures have an initial use count of 1,
302 * so we exit through here on both success and failure.
303 */
304destroy_and_out:
305 svc_destroy(serv);
306out:
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800307 mutex_unlock(&nlmsvc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 return error;
309}
310EXPORT_SYMBOL(lockd_up);
311
312/*
313 * Decrement the user count and bring down lockd if we're the last.
314 */
315void
316lockd_down(void)
317{
318 static int warned;
319
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800320 mutex_lock(&nlmsvc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 if (nlmsvc_users) {
322 if (--nlmsvc_users)
323 goto out;
324 } else
325 printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
326
327 if (!nlmsvc_pid) {
328 if (warned++ == 0)
329 printk(KERN_WARNING "lockd_down: no lockd running.\n");
330 goto out;
331 }
332 warned = 0;
333
334 kill_proc(nlmsvc_pid, SIGKILL, 1);
335 /*
336 * Wait for the lockd process to exit, but since we're holding
337 * the lockd semaphore, we can't wait around forever ...
338 */
339 clear_thread_flag(TIF_SIGPENDING);
340 interruptible_sleep_on_timeout(&lockd_exit, HZ);
341 if (nlmsvc_pid) {
342 printk(KERN_WARNING
343 "lockd_down: lockd failed to exit, clearing pid\n");
344 nlmsvc_pid = 0;
345 }
346 spin_lock_irq(&current->sighand->siglock);
347 recalc_sigpending();
348 spin_unlock_irq(&current->sighand->siglock);
349out:
Ingo Molnar353ab6e2006-03-26 01:37:12 -0800350 mutex_unlock(&nlmsvc_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351}
352EXPORT_SYMBOL(lockd_down);
353
354/*
355 * Sysctl parameters (same as module parameters, different interface).
356 */
357
358/* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
359#define CTL_UNNUMBERED -2
360
361static ctl_table nlm_sysctls[] = {
362 {
363 .ctl_name = CTL_UNNUMBERED,
364 .procname = "nlm_grace_period",
365 .data = &nlm_grace_period,
Steve Dickson7ee91ec2005-07-13 01:10:47 -0700366 .maxlen = sizeof(unsigned long),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 .mode = 0644,
368 .proc_handler = &proc_doulongvec_minmax,
369 .extra1 = (unsigned long *) &nlm_grace_period_min,
370 .extra2 = (unsigned long *) &nlm_grace_period_max,
371 },
372 {
373 .ctl_name = CTL_UNNUMBERED,
374 .procname = "nlm_timeout",
375 .data = &nlm_timeout,
Steve Dickson7ee91ec2005-07-13 01:10:47 -0700376 .maxlen = sizeof(unsigned long),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 .mode = 0644,
378 .proc_handler = &proc_doulongvec_minmax,
379 .extra1 = (unsigned long *) &nlm_timeout_min,
380 .extra2 = (unsigned long *) &nlm_timeout_max,
381 },
382 {
383 .ctl_name = CTL_UNNUMBERED,
384 .procname = "nlm_udpport",
385 .data = &nlm_udpport,
386 .maxlen = sizeof(int),
387 .mode = 0644,
388 .proc_handler = &proc_dointvec_minmax,
389 .extra1 = (int *) &nlm_port_min,
390 .extra2 = (int *) &nlm_port_max,
391 },
392 {
393 .ctl_name = CTL_UNNUMBERED,
394 .procname = "nlm_tcpport",
395 .data = &nlm_tcpport,
396 .maxlen = sizeof(int),
397 .mode = 0644,
398 .proc_handler = &proc_dointvec_minmax,
399 .extra1 = (int *) &nlm_port_min,
400 .extra2 = (int *) &nlm_port_max,
401 },
402 { .ctl_name = 0 }
403};
404
405static ctl_table nlm_sysctl_dir[] = {
406 {
407 .ctl_name = CTL_UNNUMBERED,
408 .procname = "nfs",
409 .mode = 0555,
410 .child = nlm_sysctls,
411 },
412 { .ctl_name = 0 }
413};
414
415static ctl_table nlm_sysctl_root[] = {
416 {
417 .ctl_name = CTL_FS,
418 .procname = "fs",
419 .mode = 0555,
420 .child = nlm_sysctl_dir,
421 },
422 { .ctl_name = 0 }
423};
424
425/*
426 * Module (and driverfs) parameters.
427 */
428
429#define param_set_min_max(name, type, which_strtol, min, max) \
430static int param_set_##name(const char *val, struct kernel_param *kp) \
431{ \
432 char *endp; \
433 __typeof__(type) num = which_strtol(val, &endp, 0); \
434 if (endp == val || *endp || num < (min) || num > (max)) \
435 return -EINVAL; \
436 *((int *) kp->arg) = num; \
437 return 0; \
438}
439
440static inline int is_callback(u32 proc)
441{
442 return proc == NLMPROC_GRANTED
443 || proc == NLMPROC_GRANTED_MSG
444 || proc == NLMPROC_TEST_RES
445 || proc == NLMPROC_LOCK_RES
446 || proc == NLMPROC_CANCEL_RES
447 || proc == NLMPROC_UNLOCK_RES
448 || proc == NLMPROC_NSM_NOTIFY;
449}
450
451
452static int lockd_authenticate(struct svc_rqst *rqstp)
453{
454 rqstp->rq_client = NULL;
455 switch (rqstp->rq_authop->flavour) {
456 case RPC_AUTH_NULL:
457 case RPC_AUTH_UNIX:
458 if (rqstp->rq_proc == 0)
459 return SVC_OK;
460 if (is_callback(rqstp->rq_proc)) {
461 /* Leave it to individual procedures to
462 * call nlmsvc_lookup_host(rqstp)
463 */
464 return SVC_OK;
465 }
466 return svc_set_client(rqstp);
467 }
468 return SVC_DENIED;
469}
470
471
472param_set_min_max(port, int, simple_strtol, 0, 65535)
473param_set_min_max(grace_period, unsigned long, simple_strtoul,
474 nlm_grace_period_min, nlm_grace_period_max)
475param_set_min_max(timeout, unsigned long, simple_strtoul,
476 nlm_timeout_min, nlm_timeout_max)
477
478MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
479MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
480MODULE_LICENSE("GPL");
481
482module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
483 &nlm_grace_period, 0644);
484module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
485 &nlm_timeout, 0644);
486module_param_call(nlm_udpport, param_set_port, param_get_int,
487 &nlm_udpport, 0644);
488module_param_call(nlm_tcpport, param_set_port, param_get_int,
489 &nlm_tcpport, 0644);
490
491/*
492 * Initialising and terminating the module.
493 */
494
495static int __init init_nlm(void)
496{
497 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
498 return nlm_sysctl_table ? 0 : -ENOMEM;
499}
500
501static void __exit exit_nlm(void)
502{
503 /* FIXME: delete all NLM clients */
504 nlm_shutdown_hosts();
505 unregister_sysctl_table(nlm_sysctl_table);
506}
507
508module_init(init_nlm);
509module_exit(exit_nlm);
510
511/*
512 * Define NLM program and procedures
513 */
514static struct svc_version nlmsvc_version1 = {
515 .vs_vers = 1,
516 .vs_nproc = 17,
517 .vs_proc = nlmsvc_procedures,
518 .vs_xdrsize = NLMSVC_XDRSIZE,
519};
520static struct svc_version nlmsvc_version3 = {
521 .vs_vers = 3,
522 .vs_nproc = 24,
523 .vs_proc = nlmsvc_procedures,
524 .vs_xdrsize = NLMSVC_XDRSIZE,
525};
526#ifdef CONFIG_LOCKD_V4
527static struct svc_version nlmsvc_version4 = {
528 .vs_vers = 4,
529 .vs_nproc = 24,
530 .vs_proc = nlmsvc_procedures4,
531 .vs_xdrsize = NLMSVC_XDRSIZE,
532};
533#endif
534static struct svc_version * nlmsvc_version[] = {
535 [1] = &nlmsvc_version1,
536 [3] = &nlmsvc_version3,
537#ifdef CONFIG_LOCKD_V4
538 [4] = &nlmsvc_version4,
539#endif
540};
541
542static struct svc_stat nlmsvc_stats;
543
Tobias Klausere8c96f82006-03-24 03:15:34 -0800544#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545static struct svc_program nlmsvc_program = {
546 .pg_prog = NLM_PROGRAM, /* program number */
547 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
548 .pg_vers = nlmsvc_version, /* version table */
549 .pg_name = "lockd", /* service name */
550 .pg_class = "nfsd", /* share authentication with nfsd */
551 .pg_stats = &nlmsvc_stats, /* stats table */
552 .pg_authenticate = &lockd_authenticate /* export authentication */
553};