NLM: Refactor make_socks() function
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / lockd / svc.c
CommitLineData
1da177e4
LT
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
1da177e4
LT
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/slab.h>
25#include <linux/smp.h>
26#include <linux/smp_lock.h>
353ab6e9 27#include <linux/mutex.h>
d751a7cd 28#include <linux/kthread.h>
83144186 29#include <linux/freezer.h>
1da177e4
LT
30
31#include <linux/sunrpc/types.h>
32#include <linux/sunrpc/stats.h>
33#include <linux/sunrpc/clnt.h>
34#include <linux/sunrpc/svc.h>
35#include <linux/sunrpc/svcsock.h>
24e36663 36#include <net/ip.h>
1da177e4
LT
37#include <linux/lockd/lockd.h>
38#include <linux/nfs.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;
2de59872 47EXPORT_SYMBOL_GPL(nlmsvc_ops);
1da177e4 48
353ab6e9 49static DEFINE_MUTEX(nlmsvc_mutex);
1da177e4 50static unsigned int nlmsvc_users;
d751a7cd 51static struct task_struct *nlmsvc_task;
abd1ec4e 52static struct svc_rqst *nlmsvc_rqst;
1da177e4
LT
53unsigned long nlmsvc_timeout;
54
b064ec03
CL
55/*
56 * If the kernel has IPv6 support available, always listen for
57 * both AF_INET and AF_INET6 requests.
58 */
59#if (defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)) && \
60 defined(CONFIG_SUNRPC_REGISTER_V4)
61static const sa_family_t nlmsvc_family = AF_INET6;
62#else /* (CONFIG_IPV6 || CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */
63static const sa_family_t nlmsvc_family = AF_INET;
64#endif /* (CONFIG_IPV6 || CONFIG_IPV6_MODULE) && CONFIG_SUNRPC_REGISTER_V4 */
65
1da177e4
LT
66/*
67 * These can be set at insmod time (useful for NFS as root filesystem),
68 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
69 */
70static unsigned long nlm_grace_period;
71static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
72static int nlm_udpport, nlm_tcpport;
73
c72a476b
JL
74/* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
75static unsigned int nlm_max_connections = 1024;
76
1da177e4
LT
77/*
78 * Constants needed for the sysctl interface.
79 */
80static const unsigned long nlm_grace_period_min = 0;
81static const unsigned long nlm_grace_period_max = 240;
82static const unsigned long nlm_timeout_min = 3;
83static const unsigned long nlm_timeout_max = 20;
84static const int nlm_port_min = 0, nlm_port_max = 65535;
85
90d5b180 86#ifdef CONFIG_SYSCTL
1da177e4 87static struct ctl_table_header * nlm_sysctl_table;
90d5b180 88#endif
1da177e4 89
9a8db97e 90static unsigned long get_lockd_grace_period(void)
1da177e4 91{
1da177e4
LT
92 /* Note: nlm_timeout should always be nonzero */
93 if (nlm_grace_period)
9a8db97e 94 return roundup(nlm_grace_period, nlm_timeout) * HZ;
1da177e4 95 else
9a8db97e
ME
96 return nlm_timeout * 5 * HZ;
97}
98
af558e33
BF
99static struct lock_manager lockd_manager = {
100};
9a8db97e 101
c8ab5f2a 102static void grace_ender(struct work_struct *not_used)
9a8db97e 103{
af558e33 104 locks_end_grace(&lockd_manager);
1da177e4
LT
105}
106
c8ab5f2a
BF
107static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
108
109static void set_grace_period(void)
1da177e4 110{
af558e33 111 unsigned long grace_period = get_lockd_grace_period();
c8ab5f2a 112
af558e33 113 locks_start_grace(&lockd_manager);
c8ab5f2a
BF
114 cancel_delayed_work_sync(&grace_period_end);
115 schedule_delayed_work(&grace_period_end, grace_period);
1da177e4
LT
116}
117
118/*
119 * This is the lockd kernel thread
120 */
d751a7cd
JL
121static int
122lockd(void *vrqstp)
1da177e4 123{
f97c650d 124 int err = 0, preverr = 0;
d751a7cd 125 struct svc_rqst *rqstp = vrqstp;
1da177e4 126
d751a7cd 127 /* try_to_freeze() is called from svc_recv() */
83144186 128 set_freezable();
1da177e4 129
d751a7cd 130 /* Allow SIGKILL to tell lockd to drop all of its locks */
1da177e4
LT
131 allow_signal(SIGKILL);
132
1da177e4
LT
133 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
134
d751a7cd
JL
135 /*
136 * FIXME: it would be nice if lockd didn't spend its entire life
137 * running under the BKL. At the very least, it would be good to
138 * have someone clarify what it's intended to protect here. I've
139 * seen some handwavy posts about posix locking needing to be
140 * done under the BKL, but it's far from clear.
141 */
142 lock_kernel();
143
1da177e4
LT
144 if (!nlm_timeout)
145 nlm_timeout = LOCKD_DFLT_TIMEO;
146 nlmsvc_timeout = nlm_timeout * HZ;
147
c8ab5f2a 148 set_grace_period();
1da177e4
LT
149
150 /*
151 * The main request loop. We don't terminate until the last
d751a7cd 152 * NFS mount or NFS daemon has gone away.
1da177e4 153 */
d751a7cd 154 while (!kthread_should_stop()) {
1da177e4 155 long timeout = MAX_SCHEDULE_TIMEOUT;
5216a8e7 156 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
1da177e4 157
c72a476b
JL
158 /* update sv_maxconn if it has changed */
159 rqstp->rq_server->sv_maxconn = nlm_max_connections;
160
1da177e4
LT
161 if (signalled()) {
162 flush_signals(current);
163 if (nlmsvc_ops) {
164 nlmsvc_invalidate_all();
c8ab5f2a 165 set_grace_period();
1da177e4 166 }
d751a7cd 167 continue;
1da177e4
LT
168 }
169
8fafa900
BF
170 timeout = nlmsvc_retry_blocked();
171
1da177e4
LT
172 /*
173 * Find a socket with data available and call its
174 * recvfrom routine.
175 */
6fb2b47f 176 err = svc_recv(rqstp, timeout);
f97c650d
JL
177 if (err == -EAGAIN || err == -EINTR) {
178 preverr = err;
1da177e4 179 continue;
f97c650d 180 }
1da177e4 181 if (err < 0) {
f97c650d
JL
182 if (err != preverr) {
183 printk(KERN_WARNING "%s: unexpected error "
184 "from svc_recv (%d)\n", __func__, err);
185 preverr = err;
186 }
187 schedule_timeout_interruptible(HZ);
188 continue;
1da177e4 189 }
f97c650d 190 preverr = err;
1da177e4 191
ad06e4bd
CL
192 dprintk("lockd: request from %s\n",
193 svc_print_addr(rqstp, buf, sizeof(buf)));
1da177e4 194
6fb2b47f 195 svc_process(rqstp);
1da177e4 196 }
2bd61579 197 flush_signals(current);
c8ab5f2a 198 cancel_delayed_work_sync(&grace_period_end);
2c5e7615 199 locks_end_grace(&lockd_manager);
d751a7cd
JL
200 if (nlmsvc_ops)
201 nlmsvc_invalidate_all();
202 nlm_shutdown_hosts();
d751a7cd 203 unlock_kernel();
d751a7cd 204 return 0;
1da177e4
LT
205}
206
d3fe5ea7
CL
207static int create_lockd_listener(struct svc_serv *serv, char *name,
208 unsigned short port)
209{
210 struct svc_xprt *xprt;
211
212 xprt = svc_find_xprt(serv, name, 0, 0);
213 if (xprt == NULL)
214 return svc_create_xprt(serv, name, port, SVC_SOCK_DEFAULTS);
215
216 svc_xprt_put(xprt);
217 return 0;
218}
219
482fb94e 220/*
8c3916f4
CL
221 * Ensure there are active UDP and TCP listeners for lockd.
222 *
223 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
224 * local services (such as rpc.statd) still require UDP, and
225 * some NFS servers do not yet support NLM over TCP.
226 *
227 * Returns zero if all listeners are available; otherwise a
228 * negative errno value is returned.
482fb94e 229 */
8c3916f4 230static int make_socks(struct svc_serv *serv)
24e36663 231{
482fb94e 232 static int warned;
24e36663 233 int err = 0;
482fb94e 234
d3fe5ea7
CL
235 err = create_lockd_listener(serv, "udp", nlm_udpport);
236 if (err >= 0)
237 err = create_lockd_listener(serv, "tcp", nlm_tcpport);
482fb94e 238 if (err >= 0) {
7dcf91ec 239 warned = 0;
482fb94e
CL
240 err = 0;
241 } else if (warned++ == 0)
7dcf91ec
N
242 printk(KERN_WARNING
243 "lockd_up: makesock failed, error=%d\n", err);
24e36663
N
244 return err;
245}
246
1da177e4
LT
247/*
248 * Bring up the lockd process if it's not already up.
249 */
26a41409 250int lockd_up(void)
1da177e4 251{
d751a7cd 252 struct svc_serv *serv;
d751a7cd 253 int error = 0;
1da177e4 254
353ab6e9 255 mutex_lock(&nlmsvc_mutex);
1da177e4
LT
256 /*
257 * Check whether we're already up and running.
258 */
8c3916f4 259 if (nlmsvc_rqst)
1da177e4
LT
260 goto out;
261
262 /*
263 * Sanity check: if there's no pid,
264 * we should be the first user ...
265 */
4a3ae42d 266 if (nlmsvc_users)
1da177e4
LT
267 printk(KERN_WARNING
268 "lockd_up: no pid, %d users??\n", nlmsvc_users);
269
270 error = -ENOMEM;
b064ec03 271 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, nlmsvc_family, NULL);
1da177e4
LT
272 if (!serv) {
273 printk(KERN_WARNING "lockd_up: create service failed\n");
274 goto out;
275 }
276
8c3916f4
CL
277 error = make_socks(serv);
278 if (error < 0)
1da177e4 279 goto destroy_and_out;
1da177e4
LT
280
281 /*
282 * Create the kernel thread and wait for it to start.
283 */
abd1ec4e
JL
284 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
285 if (IS_ERR(nlmsvc_rqst)) {
286 error = PTR_ERR(nlmsvc_rqst);
287 nlmsvc_rqst = NULL;
d751a7cd
JL
288 printk(KERN_WARNING
289 "lockd_up: svc_rqst allocation failed, error=%d\n",
290 error);
291 goto destroy_and_out;
292 }
293
294 svc_sock_update_bufs(serv);
c72a476b 295 serv->sv_maxconn = nlm_max_connections;
d751a7cd 296
abd1ec4e 297 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
d751a7cd
JL
298 if (IS_ERR(nlmsvc_task)) {
299 error = PTR_ERR(nlmsvc_task);
abd1ec4e 300 svc_exit_thread(nlmsvc_rqst);
d751a7cd 301 nlmsvc_task = NULL;
abd1ec4e 302 nlmsvc_rqst = NULL;
1da177e4 303 printk(KERN_WARNING
d751a7cd 304 "lockd_up: kthread_run failed, error=%d\n", error);
1da177e4
LT
305 goto destroy_and_out;
306 }
1da177e4
LT
307
308 /*
309 * Note: svc_serv structures have an initial use count of 1,
310 * so we exit through here on both success and failure.
311 */
312destroy_and_out:
313 svc_destroy(serv);
314out:
4a3ae42d
N
315 if (!error)
316 nlmsvc_users++;
353ab6e9 317 mutex_unlock(&nlmsvc_mutex);
1da177e4
LT
318 return error;
319}
2de59872 320EXPORT_SYMBOL_GPL(lockd_up);
1da177e4
LT
321
322/*
323 * Decrement the user count and bring down lockd if we're the last.
324 */
325void
326lockd_down(void)
327{
353ab6e9 328 mutex_lock(&nlmsvc_mutex);
1da177e4
LT
329 if (nlmsvc_users) {
330 if (--nlmsvc_users)
331 goto out;
d751a7cd
JL
332 } else {
333 printk(KERN_ERR "lockd_down: no users! task=%p\n",
334 nlmsvc_task);
335 BUG();
1da177e4 336 }
1da177e4 337
d751a7cd
JL
338 if (!nlmsvc_task) {
339 printk(KERN_ERR "lockd_down: no lockd running.\n");
340 BUG();
1da177e4 341 }
d751a7cd 342 kthread_stop(nlmsvc_task);
abd1ec4e
JL
343 svc_exit_thread(nlmsvc_rqst);
344 nlmsvc_task = NULL;
345 nlmsvc_rqst = NULL;
1da177e4 346out:
353ab6e9 347 mutex_unlock(&nlmsvc_mutex);
1da177e4 348}
2de59872 349EXPORT_SYMBOL_GPL(lockd_down);
1da177e4 350
90d5b180
CL
351#ifdef CONFIG_SYSCTL
352
1da177e4
LT
353/*
354 * Sysctl parameters (same as module parameters, different interface).
355 */
356
1da177e4
LT
357static ctl_table nlm_sysctls[] = {
358 {
359 .ctl_name = CTL_UNNUMBERED,
360 .procname = "nlm_grace_period",
361 .data = &nlm_grace_period,
7ee91ec1 362 .maxlen = sizeof(unsigned long),
1da177e4
LT
363 .mode = 0644,
364 .proc_handler = &proc_doulongvec_minmax,
365 .extra1 = (unsigned long *) &nlm_grace_period_min,
366 .extra2 = (unsigned long *) &nlm_grace_period_max,
367 },
368 {
369 .ctl_name = CTL_UNNUMBERED,
370 .procname = "nlm_timeout",
371 .data = &nlm_timeout,
7ee91ec1 372 .maxlen = sizeof(unsigned long),
1da177e4
LT
373 .mode = 0644,
374 .proc_handler = &proc_doulongvec_minmax,
375 .extra1 = (unsigned long *) &nlm_timeout_min,
376 .extra2 = (unsigned long *) &nlm_timeout_max,
377 },
378 {
379 .ctl_name = CTL_UNNUMBERED,
380 .procname = "nlm_udpport",
381 .data = &nlm_udpport,
382 .maxlen = sizeof(int),
383 .mode = 0644,
384 .proc_handler = &proc_dointvec_minmax,
385 .extra1 = (int *) &nlm_port_min,
386 .extra2 = (int *) &nlm_port_max,
387 },
388 {
389 .ctl_name = CTL_UNNUMBERED,
390 .procname = "nlm_tcpport",
391 .data = &nlm_tcpport,
392 .maxlen = sizeof(int),
393 .mode = 0644,
394 .proc_handler = &proc_dointvec_minmax,
395 .extra1 = (int *) &nlm_port_min,
396 .extra2 = (int *) &nlm_port_max,
397 },
abd1f500
OK
398 {
399 .ctl_name = CTL_UNNUMBERED,
400 .procname = "nsm_use_hostnames",
401 .data = &nsm_use_hostnames,
402 .maxlen = sizeof(int),
403 .mode = 0644,
404 .proc_handler = &proc_dointvec,
405 },
460f5cac
OK
406 {
407 .ctl_name = CTL_UNNUMBERED,
408 .procname = "nsm_local_state",
409 .data = &nsm_local_state,
410 .maxlen = sizeof(int),
411 .mode = 0644,
412 .proc_handler = &proc_dointvec,
413 },
1da177e4
LT
414 { .ctl_name = 0 }
415};
416
417static ctl_table nlm_sysctl_dir[] = {
418 {
419 .ctl_name = CTL_UNNUMBERED,
420 .procname = "nfs",
421 .mode = 0555,
422 .child = nlm_sysctls,
423 },
424 { .ctl_name = 0 }
425};
426
427static ctl_table nlm_sysctl_root[] = {
428 {
429 .ctl_name = CTL_FS,
430 .procname = "fs",
431 .mode = 0555,
432 .child = nlm_sysctl_dir,
433 },
434 { .ctl_name = 0 }
435};
436
90d5b180
CL
437#endif /* CONFIG_SYSCTL */
438
1da177e4 439/*
405ae7d3 440 * Module (and sysfs) parameters.
1da177e4
LT
441 */
442
443#define param_set_min_max(name, type, which_strtol, min, max) \
444static int param_set_##name(const char *val, struct kernel_param *kp) \
445{ \
446 char *endp; \
447 __typeof__(type) num = which_strtol(val, &endp, 0); \
448 if (endp == val || *endp || num < (min) || num > (max)) \
449 return -EINVAL; \
450 *((int *) kp->arg) = num; \
451 return 0; \
452}
453
454static inline int is_callback(u32 proc)
455{
456 return proc == NLMPROC_GRANTED
457 || proc == NLMPROC_GRANTED_MSG
458 || proc == NLMPROC_TEST_RES
459 || proc == NLMPROC_LOCK_RES
460 || proc == NLMPROC_CANCEL_RES
461 || proc == NLMPROC_UNLOCK_RES
462 || proc == NLMPROC_NSM_NOTIFY;
463}
464
465
466static int lockd_authenticate(struct svc_rqst *rqstp)
467{
468 rqstp->rq_client = NULL;
469 switch (rqstp->rq_authop->flavour) {
470 case RPC_AUTH_NULL:
471 case RPC_AUTH_UNIX:
472 if (rqstp->rq_proc == 0)
473 return SVC_OK;
474 if (is_callback(rqstp->rq_proc)) {
475 /* Leave it to individual procedures to
476 * call nlmsvc_lookup_host(rqstp)
477 */
478 return SVC_OK;
479 }
480 return svc_set_client(rqstp);
481 }
482 return SVC_DENIED;
483}
484
485
486param_set_min_max(port, int, simple_strtol, 0, 65535)
487param_set_min_max(grace_period, unsigned long, simple_strtoul,
488 nlm_grace_period_min, nlm_grace_period_max)
489param_set_min_max(timeout, unsigned long, simple_strtoul,
490 nlm_timeout_min, nlm_timeout_max)
491
492MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
493MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
494MODULE_LICENSE("GPL");
495
496module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
497 &nlm_grace_period, 0644);
498module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
499 &nlm_timeout, 0644);
500module_param_call(nlm_udpport, param_set_port, param_get_int,
501 &nlm_udpport, 0644);
502module_param_call(nlm_tcpport, param_set_port, param_get_int,
503 &nlm_tcpport, 0644);
abd1f500 504module_param(nsm_use_hostnames, bool, 0644);
c72a476b 505module_param(nlm_max_connections, uint, 0644);
1da177e4
LT
506
507/*
508 * Initialising and terminating the module.
509 */
510
511static int __init init_nlm(void)
512{
90d5b180 513#ifdef CONFIG_SYSCTL
0b4d4147 514 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
1da177e4 515 return nlm_sysctl_table ? 0 : -ENOMEM;
90d5b180
CL
516#else
517 return 0;
518#endif
1da177e4
LT
519}
520
521static void __exit exit_nlm(void)
522{
523 /* FIXME: delete all NLM clients */
524 nlm_shutdown_hosts();
90d5b180 525#ifdef CONFIG_SYSCTL
1da177e4 526 unregister_sysctl_table(nlm_sysctl_table);
90d5b180 527#endif
1da177e4
LT
528}
529
530module_init(init_nlm);
531module_exit(exit_nlm);
532
533/*
534 * Define NLM program and procedures
535 */
536static struct svc_version nlmsvc_version1 = {
537 .vs_vers = 1,
538 .vs_nproc = 17,
539 .vs_proc = nlmsvc_procedures,
540 .vs_xdrsize = NLMSVC_XDRSIZE,
541};
542static struct svc_version nlmsvc_version3 = {
543 .vs_vers = 3,
544 .vs_nproc = 24,
545 .vs_proc = nlmsvc_procedures,
546 .vs_xdrsize = NLMSVC_XDRSIZE,
547};
548#ifdef CONFIG_LOCKD_V4
549static struct svc_version nlmsvc_version4 = {
550 .vs_vers = 4,
551 .vs_nproc = 24,
552 .vs_proc = nlmsvc_procedures4,
553 .vs_xdrsize = NLMSVC_XDRSIZE,
554};
555#endif
556static struct svc_version * nlmsvc_version[] = {
557 [1] = &nlmsvc_version1,
558 [3] = &nlmsvc_version3,
559#ifdef CONFIG_LOCKD_V4
560 [4] = &nlmsvc_version4,
561#endif
562};
563
564static struct svc_stat nlmsvc_stats;
565
e8c96f8c 566#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4
LT
567static struct svc_program nlmsvc_program = {
568 .pg_prog = NLM_PROGRAM, /* program number */
569 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
570 .pg_vers = nlmsvc_version, /* version table */
571 .pg_name = "lockd", /* service name */
572 .pg_class = "nfsd", /* share authentication with nfsd */
573 .pg_stats = &nlmsvc_stats, /* stats table */
574 .pg_authenticate = &lockd_authenticate /* export authentication */
575};