nfsd: Ensure nfsv4 calls the underlying filesystem on LOCKT
[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
482fb94e 207/*
8c3916f4
CL
208 * Ensure there are active UDP and TCP listeners for lockd.
209 *
210 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
211 * local services (such as rpc.statd) still require UDP, and
212 * some NFS servers do not yet support NLM over TCP.
213 *
214 * Returns zero if all listeners are available; otherwise a
215 * negative errno value is returned.
482fb94e 216 */
8c3916f4 217static int make_socks(struct svc_serv *serv)
24e36663 218{
482fb94e 219 static int warned;
a217813f 220 struct svc_xprt *xprt;
24e36663 221 int err = 0;
482fb94e 222
8c3916f4
CL
223 xprt = svc_find_xprt(serv, "udp", 0, 0);
224 if (!xprt)
225 err = svc_create_xprt(serv, "udp", nlm_udpport,
226 SVC_SOCK_DEFAULTS);
227 else
228 svc_xprt_put(xprt);
229 if (err >= 0) {
a217813f
TT
230 xprt = svc_find_xprt(serv, "tcp", 0, 0);
231 if (!xprt)
d7c9f1ed
TT
232 err = svc_create_xprt(serv, "tcp", nlm_tcpport,
233 SVC_SOCK_DEFAULTS);
a217813f
TT
234 else
235 svc_xprt_put(xprt);
236 }
482fb94e 237 if (err >= 0) {
7dcf91ec 238 warned = 0;
482fb94e
CL
239 err = 0;
240 } else if (warned++ == 0)
7dcf91ec
N
241 printk(KERN_WARNING
242 "lockd_up: makesock failed, error=%d\n", err);
24e36663
N
243 return err;
244}
245
1da177e4
LT
246/*
247 * Bring up the lockd process if it's not already up.
248 */
26a41409 249int lockd_up(void)
1da177e4 250{
d751a7cd 251 struct svc_serv *serv;
d751a7cd 252 int error = 0;
1da177e4 253
353ab6e9 254 mutex_lock(&nlmsvc_mutex);
1da177e4
LT
255 /*
256 * Check whether we're already up and running.
257 */
8c3916f4 258 if (nlmsvc_rqst)
1da177e4
LT
259 goto out;
260
261 /*
262 * Sanity check: if there's no pid,
263 * we should be the first user ...
264 */
4a3ae42d 265 if (nlmsvc_users)
1da177e4
LT
266 printk(KERN_WARNING
267 "lockd_up: no pid, %d users??\n", nlmsvc_users);
268
269 error = -ENOMEM;
b064ec03 270 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, nlmsvc_family, NULL);
1da177e4
LT
271 if (!serv) {
272 printk(KERN_WARNING "lockd_up: create service failed\n");
273 goto out;
274 }
275
8c3916f4
CL
276 error = make_socks(serv);
277 if (error < 0)
1da177e4 278 goto destroy_and_out;
1da177e4
LT
279
280 /*
281 * Create the kernel thread and wait for it to start.
282 */
abd1ec4e
JL
283 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
284 if (IS_ERR(nlmsvc_rqst)) {
285 error = PTR_ERR(nlmsvc_rqst);
286 nlmsvc_rqst = NULL;
d751a7cd
JL
287 printk(KERN_WARNING
288 "lockd_up: svc_rqst allocation failed, error=%d\n",
289 error);
290 goto destroy_and_out;
291 }
292
293 svc_sock_update_bufs(serv);
c72a476b 294 serv->sv_maxconn = nlm_max_connections;
d751a7cd 295
abd1ec4e 296 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
d751a7cd
JL
297 if (IS_ERR(nlmsvc_task)) {
298 error = PTR_ERR(nlmsvc_task);
abd1ec4e 299 svc_exit_thread(nlmsvc_rqst);
d751a7cd 300 nlmsvc_task = NULL;
abd1ec4e 301 nlmsvc_rqst = NULL;
1da177e4 302 printk(KERN_WARNING
d751a7cd 303 "lockd_up: kthread_run failed, error=%d\n", error);
1da177e4
LT
304 goto destroy_and_out;
305 }
1da177e4
LT
306
307 /*
308 * Note: svc_serv structures have an initial use count of 1,
309 * so we exit through here on both success and failure.
310 */
311destroy_and_out:
312 svc_destroy(serv);
313out:
4a3ae42d
N
314 if (!error)
315 nlmsvc_users++;
353ab6e9 316 mutex_unlock(&nlmsvc_mutex);
1da177e4
LT
317 return error;
318}
2de59872 319EXPORT_SYMBOL_GPL(lockd_up);
1da177e4
LT
320
321/*
322 * Decrement the user count and bring down lockd if we're the last.
323 */
324void
325lockd_down(void)
326{
353ab6e9 327 mutex_lock(&nlmsvc_mutex);
1da177e4
LT
328 if (nlmsvc_users) {
329 if (--nlmsvc_users)
330 goto out;
d751a7cd
JL
331 } else {
332 printk(KERN_ERR "lockd_down: no users! task=%p\n",
333 nlmsvc_task);
334 BUG();
1da177e4 335 }
1da177e4 336
d751a7cd
JL
337 if (!nlmsvc_task) {
338 printk(KERN_ERR "lockd_down: no lockd running.\n");
339 BUG();
1da177e4 340 }
d751a7cd 341 kthread_stop(nlmsvc_task);
abd1ec4e
JL
342 svc_exit_thread(nlmsvc_rqst);
343 nlmsvc_task = NULL;
344 nlmsvc_rqst = NULL;
1da177e4 345out:
353ab6e9 346 mutex_unlock(&nlmsvc_mutex);
1da177e4 347}
2de59872 348EXPORT_SYMBOL_GPL(lockd_down);
1da177e4 349
90d5b180
CL
350#ifdef CONFIG_SYSCTL
351
1da177e4
LT
352/*
353 * Sysctl parameters (same as module parameters, different interface).
354 */
355
1da177e4
LT
356static ctl_table nlm_sysctls[] = {
357 {
358 .ctl_name = CTL_UNNUMBERED,
359 .procname = "nlm_grace_period",
360 .data = &nlm_grace_period,
7ee91ec1 361 .maxlen = sizeof(unsigned long),
1da177e4
LT
362 .mode = 0644,
363 .proc_handler = &proc_doulongvec_minmax,
364 .extra1 = (unsigned long *) &nlm_grace_period_min,
365 .extra2 = (unsigned long *) &nlm_grace_period_max,
366 },
367 {
368 .ctl_name = CTL_UNNUMBERED,
369 .procname = "nlm_timeout",
370 .data = &nlm_timeout,
7ee91ec1 371 .maxlen = sizeof(unsigned long),
1da177e4
LT
372 .mode = 0644,
373 .proc_handler = &proc_doulongvec_minmax,
374 .extra1 = (unsigned long *) &nlm_timeout_min,
375 .extra2 = (unsigned long *) &nlm_timeout_max,
376 },
377 {
378 .ctl_name = CTL_UNNUMBERED,
379 .procname = "nlm_udpport",
380 .data = &nlm_udpport,
381 .maxlen = sizeof(int),
382 .mode = 0644,
383 .proc_handler = &proc_dointvec_minmax,
384 .extra1 = (int *) &nlm_port_min,
385 .extra2 = (int *) &nlm_port_max,
386 },
387 {
388 .ctl_name = CTL_UNNUMBERED,
389 .procname = "nlm_tcpport",
390 .data = &nlm_tcpport,
391 .maxlen = sizeof(int),
392 .mode = 0644,
393 .proc_handler = &proc_dointvec_minmax,
394 .extra1 = (int *) &nlm_port_min,
395 .extra2 = (int *) &nlm_port_max,
396 },
abd1f500
OK
397 {
398 .ctl_name = CTL_UNNUMBERED,
399 .procname = "nsm_use_hostnames",
400 .data = &nsm_use_hostnames,
401 .maxlen = sizeof(int),
402 .mode = 0644,
403 .proc_handler = &proc_dointvec,
404 },
460f5cac
OK
405 {
406 .ctl_name = CTL_UNNUMBERED,
407 .procname = "nsm_local_state",
408 .data = &nsm_local_state,
409 .maxlen = sizeof(int),
410 .mode = 0644,
411 .proc_handler = &proc_dointvec,
412 },
1da177e4
LT
413 { .ctl_name = 0 }
414};
415
416static ctl_table nlm_sysctl_dir[] = {
417 {
418 .ctl_name = CTL_UNNUMBERED,
419 .procname = "nfs",
420 .mode = 0555,
421 .child = nlm_sysctls,
422 },
423 { .ctl_name = 0 }
424};
425
426static ctl_table nlm_sysctl_root[] = {
427 {
428 .ctl_name = CTL_FS,
429 .procname = "fs",
430 .mode = 0555,
431 .child = nlm_sysctl_dir,
432 },
433 { .ctl_name = 0 }
434};
435
90d5b180
CL
436#endif /* CONFIG_SYSCTL */
437
1da177e4 438/*
405ae7d3 439 * Module (and sysfs) parameters.
1da177e4
LT
440 */
441
442#define param_set_min_max(name, type, which_strtol, min, max) \
443static int param_set_##name(const char *val, struct kernel_param *kp) \
444{ \
445 char *endp; \
446 __typeof__(type) num = which_strtol(val, &endp, 0); \
447 if (endp == val || *endp || num < (min) || num > (max)) \
448 return -EINVAL; \
449 *((int *) kp->arg) = num; \
450 return 0; \
451}
452
453static inline int is_callback(u32 proc)
454{
455 return proc == NLMPROC_GRANTED
456 || proc == NLMPROC_GRANTED_MSG
457 || proc == NLMPROC_TEST_RES
458 || proc == NLMPROC_LOCK_RES
459 || proc == NLMPROC_CANCEL_RES
460 || proc == NLMPROC_UNLOCK_RES
461 || proc == NLMPROC_NSM_NOTIFY;
462}
463
464
465static int lockd_authenticate(struct svc_rqst *rqstp)
466{
467 rqstp->rq_client = NULL;
468 switch (rqstp->rq_authop->flavour) {
469 case RPC_AUTH_NULL:
470 case RPC_AUTH_UNIX:
471 if (rqstp->rq_proc == 0)
472 return SVC_OK;
473 if (is_callback(rqstp->rq_proc)) {
474 /* Leave it to individual procedures to
475 * call nlmsvc_lookup_host(rqstp)
476 */
477 return SVC_OK;
478 }
479 return svc_set_client(rqstp);
480 }
481 return SVC_DENIED;
482}
483
484
485param_set_min_max(port, int, simple_strtol, 0, 65535)
486param_set_min_max(grace_period, unsigned long, simple_strtoul,
487 nlm_grace_period_min, nlm_grace_period_max)
488param_set_min_max(timeout, unsigned long, simple_strtoul,
489 nlm_timeout_min, nlm_timeout_max)
490
491MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
492MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
493MODULE_LICENSE("GPL");
494
495module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
496 &nlm_grace_period, 0644);
497module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
498 &nlm_timeout, 0644);
499module_param_call(nlm_udpport, param_set_port, param_get_int,
500 &nlm_udpport, 0644);
501module_param_call(nlm_tcpport, param_set_port, param_get_int,
502 &nlm_tcpport, 0644);
abd1f500 503module_param(nsm_use_hostnames, bool, 0644);
c72a476b 504module_param(nlm_max_connections, uint, 0644);
1da177e4
LT
505
506/*
507 * Initialising and terminating the module.
508 */
509
510static int __init init_nlm(void)
511{
90d5b180 512#ifdef CONFIG_SYSCTL
0b4d4147 513 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
1da177e4 514 return nlm_sysctl_table ? 0 : -ENOMEM;
90d5b180
CL
515#else
516 return 0;
517#endif
1da177e4
LT
518}
519
520static void __exit exit_nlm(void)
521{
522 /* FIXME: delete all NLM clients */
523 nlm_shutdown_hosts();
90d5b180 524#ifdef CONFIG_SYSCTL
1da177e4 525 unregister_sysctl_table(nlm_sysctl_table);
90d5b180 526#endif
1da177e4
LT
527}
528
529module_init(init_nlm);
530module_exit(exit_nlm);
531
532/*
533 * Define NLM program and procedures
534 */
535static struct svc_version nlmsvc_version1 = {
536 .vs_vers = 1,
537 .vs_nproc = 17,
538 .vs_proc = nlmsvc_procedures,
539 .vs_xdrsize = NLMSVC_XDRSIZE,
540};
541static struct svc_version nlmsvc_version3 = {
542 .vs_vers = 3,
543 .vs_nproc = 24,
544 .vs_proc = nlmsvc_procedures,
545 .vs_xdrsize = NLMSVC_XDRSIZE,
546};
547#ifdef CONFIG_LOCKD_V4
548static struct svc_version nlmsvc_version4 = {
549 .vs_vers = 4,
550 .vs_nproc = 24,
551 .vs_proc = nlmsvc_procedures4,
552 .vs_xdrsize = NLMSVC_XDRSIZE,
553};
554#endif
555static struct svc_version * nlmsvc_version[] = {
556 [1] = &nlmsvc_version1,
557 [3] = &nlmsvc_version3,
558#ifdef CONFIG_LOCKD_V4
559 [4] = &nlmsvc_version4,
560#endif
561};
562
563static struct svc_stat nlmsvc_stats;
564
e8c96f8c 565#define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
1da177e4
LT
566static struct svc_program nlmsvc_program = {
567 .pg_prog = NLM_PROGRAM, /* program number */
568 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
569 .pg_vers = nlmsvc_version, /* version table */
570 .pg_name = "lockd", /* service name */
571 .pg_class = "nfsd", /* share authentication with nfsd */
572 .pg_stats = &nlmsvc_stats, /* stats table */
573 .pg_authenticate = &lockd_authenticate /* export authentication */
574};