USB: kill BKL in skeleton driver
[linux-2.6/mini2440.git] / fs / lockd / svc.c
blob126b1bf02c0ec2d8b5c051eb1e29acf27d6a32b3
1 /*
2 * linux/fs/lockd/svc.c
4 * This is the central lockd service.
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?
10 * Authors: Olaf Kirch (okir@monad.swb.de)
12 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/sysctl.h>
18 #include <linux/moduleparam.h>
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>
27 #include <linux/mutex.h>
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/lockd/sm_inter.h>
37 #include <linux/nfs.h>
39 #define NLMDBG_FACILITY NLMDBG_SVC
40 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
41 #define ALLOWED_SIGS (sigmask(SIGKILL))
43 static struct svc_program nlmsvc_program;
45 struct nlmsvc_binding * nlmsvc_ops;
46 EXPORT_SYMBOL(nlmsvc_ops);
48 static DEFINE_MUTEX(nlmsvc_mutex);
49 static unsigned int nlmsvc_users;
50 static pid_t nlmsvc_pid;
51 static struct svc_serv *nlmsvc_serv;
52 int nlmsvc_grace_period;
53 unsigned long nlmsvc_timeout;
55 static DECLARE_COMPLETION(lockd_start_done);
56 static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
59 * These can be set at insmod time (useful for NFS as root filesystem),
60 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
62 static unsigned long nlm_grace_period;
63 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
64 static int nlm_udpport, nlm_tcpport;
65 int nsm_use_hostnames = 0;
68 * Constants needed for the sysctl interface.
70 static const unsigned long nlm_grace_period_min = 0;
71 static const unsigned long nlm_grace_period_max = 240;
72 static const unsigned long nlm_timeout_min = 3;
73 static const unsigned long nlm_timeout_max = 20;
74 static const int nlm_port_min = 0, nlm_port_max = 65535;
76 static struct ctl_table_header * nlm_sysctl_table;
78 static unsigned long set_grace_period(void)
80 unsigned long grace_period;
82 /* Note: nlm_timeout should always be nonzero */
83 if (nlm_grace_period)
84 grace_period = ((nlm_grace_period + nlm_timeout - 1)
85 / nlm_timeout) * nlm_timeout * HZ;
86 else
87 grace_period = nlm_timeout * 5 * HZ;
88 nlmsvc_grace_period = 1;
89 return grace_period + jiffies;
92 static inline void clear_grace_period(void)
94 nlmsvc_grace_period = 0;
98 * This is the lockd kernel thread
100 static void
101 lockd(struct svc_rqst *rqstp)
103 int err = 0;
104 unsigned long grace_period_expire;
106 /* Lock module and set up kernel thread */
107 /* lockd_up is waiting for us to startup, so will
108 * be holding a reference to this module, so it
109 * is safe to just claim another reference
111 __module_get(THIS_MODULE);
112 lock_kernel();
115 * Let our maker know we're running.
117 nlmsvc_pid = current->pid;
118 nlmsvc_serv = rqstp->rq_server;
119 complete(&lockd_start_done);
121 daemonize("lockd");
123 /* Process request with signals blocked, but allow SIGKILL. */
124 allow_signal(SIGKILL);
126 /* kick rpciod */
127 rpciod_up();
129 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
131 if (!nlm_timeout)
132 nlm_timeout = LOCKD_DFLT_TIMEO;
133 nlmsvc_timeout = nlm_timeout * HZ;
135 grace_period_expire = set_grace_period();
138 * The main request loop. We don't terminate until the last
139 * NFS mount or NFS daemon has gone away, and we've been sent a
140 * signal, or else another process has taken over our job.
142 while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
143 long timeout = MAX_SCHEDULE_TIMEOUT;
144 char buf[RPC_MAX_ADDRBUFLEN];
146 if (signalled()) {
147 flush_signals(current);
148 if (nlmsvc_ops) {
149 nlmsvc_invalidate_all();
150 grace_period_expire = set_grace_period();
155 * Retry any blocked locks that have been notified by
156 * the VFS. Don't do this during grace period.
157 * (Theoretically, there shouldn't even be blocked locks
158 * during grace period).
160 if (!nlmsvc_grace_period) {
161 timeout = nlmsvc_retry_blocked();
162 } else if (time_before(grace_period_expire, jiffies))
163 clear_grace_period();
166 * Find a socket with data available and call its
167 * recvfrom routine.
169 err = svc_recv(rqstp, timeout);
170 if (err == -EAGAIN || err == -EINTR)
171 continue;
172 if (err < 0) {
173 printk(KERN_WARNING
174 "lockd: terminating on error %d\n",
175 -err);
176 break;
179 dprintk("lockd: request from %s\n",
180 svc_print_addr(rqstp, buf, sizeof(buf)));
182 svc_process(rqstp);
185 flush_signals(current);
188 * Check whether there's a new lockd process before
189 * shutting down the hosts and clearing the slot.
191 if (!nlmsvc_pid || current->pid == nlmsvc_pid) {
192 if (nlmsvc_ops)
193 nlmsvc_invalidate_all();
194 nlm_shutdown_hosts();
195 nlmsvc_pid = 0;
196 nlmsvc_serv = NULL;
197 } else
198 printk(KERN_DEBUG
199 "lockd: new process, skipping host shutdown\n");
200 wake_up(&lockd_exit);
202 /* Exit the RPC thread */
203 svc_exit_thread(rqstp);
205 /* release rpciod */
206 rpciod_down();
208 /* Release module */
209 unlock_kernel();
210 module_put_and_exit(0);
214 static int find_socket(struct svc_serv *serv, int proto)
216 struct svc_sock *svsk;
217 int found = 0;
218 list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
219 if (svsk->sk_sk->sk_protocol == proto) {
220 found = 1;
221 break;
223 return found;
227 * Make any sockets that are needed but not present.
228 * If nlm_udpport or nlm_tcpport were set as module
229 * options, make those sockets unconditionally
231 static int make_socks(struct svc_serv *serv, int proto)
233 static int warned;
234 int err = 0;
236 if (proto == IPPROTO_UDP || nlm_udpport)
237 if (!find_socket(serv, IPPROTO_UDP))
238 err = svc_makesock(serv, IPPROTO_UDP, nlm_udpport,
239 SVC_SOCK_DEFAULTS);
240 if (err >= 0 && (proto == IPPROTO_TCP || nlm_tcpport))
241 if (!find_socket(serv, IPPROTO_TCP))
242 err = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport,
243 SVC_SOCK_DEFAULTS);
245 if (err >= 0) {
246 warned = 0;
247 err = 0;
248 } else if (warned++ == 0)
249 printk(KERN_WARNING
250 "lockd_up: makesock failed, error=%d\n", err);
251 return err;
255 * Bring up the lockd process if it's not already up.
258 lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
260 struct svc_serv * serv;
261 int error = 0;
263 mutex_lock(&nlmsvc_mutex);
265 * Check whether we're already up and running.
267 if (nlmsvc_pid) {
268 if (proto)
269 error = make_socks(nlmsvc_serv, proto);
270 goto out;
274 * Sanity check: if there's no pid,
275 * we should be the first user ...
277 if (nlmsvc_users)
278 printk(KERN_WARNING
279 "lockd_up: no pid, %d users??\n", nlmsvc_users);
281 error = -ENOMEM;
282 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
283 if (!serv) {
284 printk(KERN_WARNING "lockd_up: create service failed\n");
285 goto out;
288 if ((error = make_socks(serv, proto)) < 0)
289 goto destroy_and_out;
292 * Create the kernel thread and wait for it to start.
294 error = svc_create_thread(lockd, serv);
295 if (error) {
296 printk(KERN_WARNING
297 "lockd_up: create thread failed, error=%d\n", error);
298 goto destroy_and_out;
300 wait_for_completion(&lockd_start_done);
303 * Note: svc_serv structures have an initial use count of 1,
304 * so we exit through here on both success and failure.
306 destroy_and_out:
307 svc_destroy(serv);
308 out:
309 if (!error)
310 nlmsvc_users++;
311 mutex_unlock(&nlmsvc_mutex);
312 return error;
314 EXPORT_SYMBOL(lockd_up);
317 * Decrement the user count and bring down lockd if we're the last.
319 void
320 lockd_down(void)
322 static int warned;
324 mutex_lock(&nlmsvc_mutex);
325 if (nlmsvc_users) {
326 if (--nlmsvc_users)
327 goto out;
328 } else
329 printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
331 if (!nlmsvc_pid) {
332 if (warned++ == 0)
333 printk(KERN_WARNING "lockd_down: no lockd running.\n");
334 goto out;
336 warned = 0;
338 kill_proc(nlmsvc_pid, SIGKILL, 1);
340 * Wait for the lockd process to exit, but since we're holding
341 * the lockd semaphore, we can't wait around forever ...
343 clear_thread_flag(TIF_SIGPENDING);
344 interruptible_sleep_on_timeout(&lockd_exit, HZ);
345 if (nlmsvc_pid) {
346 printk(KERN_WARNING
347 "lockd_down: lockd failed to exit, clearing pid\n");
348 nlmsvc_pid = 0;
350 spin_lock_irq(&current->sighand->siglock);
351 recalc_sigpending();
352 spin_unlock_irq(&current->sighand->siglock);
353 out:
354 mutex_unlock(&nlmsvc_mutex);
356 EXPORT_SYMBOL(lockd_down);
359 * Sysctl parameters (same as module parameters, different interface).
362 static ctl_table nlm_sysctls[] = {
364 .ctl_name = CTL_UNNUMBERED,
365 .procname = "nlm_grace_period",
366 .data = &nlm_grace_period,
367 .maxlen = sizeof(unsigned long),
368 .mode = 0644,
369 .proc_handler = &proc_doulongvec_minmax,
370 .extra1 = (unsigned long *) &nlm_grace_period_min,
371 .extra2 = (unsigned long *) &nlm_grace_period_max,
374 .ctl_name = CTL_UNNUMBERED,
375 .procname = "nlm_timeout",
376 .data = &nlm_timeout,
377 .maxlen = sizeof(unsigned long),
378 .mode = 0644,
379 .proc_handler = &proc_doulongvec_minmax,
380 .extra1 = (unsigned long *) &nlm_timeout_min,
381 .extra2 = (unsigned long *) &nlm_timeout_max,
384 .ctl_name = CTL_UNNUMBERED,
385 .procname = "nlm_udpport",
386 .data = &nlm_udpport,
387 .maxlen = sizeof(int),
388 .mode = 0644,
389 .proc_handler = &proc_dointvec_minmax,
390 .extra1 = (int *) &nlm_port_min,
391 .extra2 = (int *) &nlm_port_max,
394 .ctl_name = CTL_UNNUMBERED,
395 .procname = "nlm_tcpport",
396 .data = &nlm_tcpport,
397 .maxlen = sizeof(int),
398 .mode = 0644,
399 .proc_handler = &proc_dointvec_minmax,
400 .extra1 = (int *) &nlm_port_min,
401 .extra2 = (int *) &nlm_port_max,
404 .ctl_name = CTL_UNNUMBERED,
405 .procname = "nsm_use_hostnames",
406 .data = &nsm_use_hostnames,
407 .maxlen = sizeof(int),
408 .mode = 0644,
409 .proc_handler = &proc_dointvec,
412 .ctl_name = CTL_UNNUMBERED,
413 .procname = "nsm_local_state",
414 .data = &nsm_local_state,
415 .maxlen = sizeof(int),
416 .mode = 0644,
417 .proc_handler = &proc_dointvec,
419 { .ctl_name = 0 }
422 static ctl_table nlm_sysctl_dir[] = {
424 .ctl_name = CTL_UNNUMBERED,
425 .procname = "nfs",
426 .mode = 0555,
427 .child = nlm_sysctls,
429 { .ctl_name = 0 }
432 static ctl_table nlm_sysctl_root[] = {
434 .ctl_name = CTL_FS,
435 .procname = "fs",
436 .mode = 0555,
437 .child = nlm_sysctl_dir,
439 { .ctl_name = 0 }
443 * Module (and sysfs) parameters.
446 #define param_set_min_max(name, type, which_strtol, min, max) \
447 static int param_set_##name(const char *val, struct kernel_param *kp) \
449 char *endp; \
450 __typeof__(type) num = which_strtol(val, &endp, 0); \
451 if (endp == val || *endp || num < (min) || num > (max)) \
452 return -EINVAL; \
453 *((int *) kp->arg) = num; \
454 return 0; \
457 static inline int is_callback(u32 proc)
459 return proc == NLMPROC_GRANTED
460 || proc == NLMPROC_GRANTED_MSG
461 || proc == NLMPROC_TEST_RES
462 || proc == NLMPROC_LOCK_RES
463 || proc == NLMPROC_CANCEL_RES
464 || proc == NLMPROC_UNLOCK_RES
465 || proc == NLMPROC_NSM_NOTIFY;
469 static int lockd_authenticate(struct svc_rqst *rqstp)
471 rqstp->rq_client = NULL;
472 switch (rqstp->rq_authop->flavour) {
473 case RPC_AUTH_NULL:
474 case RPC_AUTH_UNIX:
475 if (rqstp->rq_proc == 0)
476 return SVC_OK;
477 if (is_callback(rqstp->rq_proc)) {
478 /* Leave it to individual procedures to
479 * call nlmsvc_lookup_host(rqstp)
481 return SVC_OK;
483 return svc_set_client(rqstp);
485 return SVC_DENIED;
489 param_set_min_max(port, int, simple_strtol, 0, 65535)
490 param_set_min_max(grace_period, unsigned long, simple_strtoul,
491 nlm_grace_period_min, nlm_grace_period_max)
492 param_set_min_max(timeout, unsigned long, simple_strtoul,
493 nlm_timeout_min, nlm_timeout_max)
495 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
496 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
497 MODULE_LICENSE("GPL");
499 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
500 &nlm_grace_period, 0644);
501 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
502 &nlm_timeout, 0644);
503 module_param_call(nlm_udpport, param_set_port, param_get_int,
504 &nlm_udpport, 0644);
505 module_param_call(nlm_tcpport, param_set_port, param_get_int,
506 &nlm_tcpport, 0644);
507 module_param(nsm_use_hostnames, bool, 0644);
510 * Initialising and terminating the module.
513 static int __init init_nlm(void)
515 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
516 return nlm_sysctl_table ? 0 : -ENOMEM;
519 static void __exit exit_nlm(void)
521 /* FIXME: delete all NLM clients */
522 nlm_shutdown_hosts();
523 unregister_sysctl_table(nlm_sysctl_table);
526 module_init(init_nlm);
527 module_exit(exit_nlm);
530 * Define NLM program and procedures
532 static struct svc_version nlmsvc_version1 = {
533 .vs_vers = 1,
534 .vs_nproc = 17,
535 .vs_proc = nlmsvc_procedures,
536 .vs_xdrsize = NLMSVC_XDRSIZE,
538 static struct svc_version nlmsvc_version3 = {
539 .vs_vers = 3,
540 .vs_nproc = 24,
541 .vs_proc = nlmsvc_procedures,
542 .vs_xdrsize = NLMSVC_XDRSIZE,
544 #ifdef CONFIG_LOCKD_V4
545 static struct svc_version nlmsvc_version4 = {
546 .vs_vers = 4,
547 .vs_nproc = 24,
548 .vs_proc = nlmsvc_procedures4,
549 .vs_xdrsize = NLMSVC_XDRSIZE,
551 #endif
552 static struct svc_version * nlmsvc_version[] = {
553 [1] = &nlmsvc_version1,
554 [3] = &nlmsvc_version3,
555 #ifdef CONFIG_LOCKD_V4
556 [4] = &nlmsvc_version4,
557 #endif
560 static struct svc_stat nlmsvc_stats;
562 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
563 static struct svc_program nlmsvc_program = {
564 .pg_prog = NLM_PROGRAM, /* program number */
565 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
566 .pg_vers = nlmsvc_version, /* version table */
567 .pg_name = "lockd", /* service name */
568 .pg_class = "nfsd", /* share authentication with nfsd */
569 .pg_stats = &nlmsvc_stats, /* stats table */
570 .pg_authenticate = &lockd_authenticate /* export authentication */