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/config.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/sysctl.h>
19 #include <linux/moduleparam.h>
21 #include <linux/sched.h>
22 #include <linux/errno.h>
24 #include <linux/uio.h>
25 #include <linux/slab.h>
26 #include <linux/smp.h>
27 #include <linux/smp_lock.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 <linux/lockd/lockd.h>
35 #include <linux/nfs.h>
37 #define NLMDBG_FACILITY NLMDBG_SVC
38 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
39 #define ALLOWED_SIGS (sigmask(SIGKILL))
41 extern struct svc_program nlmsvc_program;
42 struct nlmsvc_binding * nlmsvc_ops;
43 static DECLARE_MUTEX(nlmsvc_sema);
44 static unsigned int nlmsvc_users;
45 static pid_t nlmsvc_pid;
46 int nlmsvc_grace_period;
47 unsigned long nlmsvc_timeout;
49 static DECLARE_MUTEX_LOCKED(lockd_start);
50 static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
53 * These can be set at insmod time (useful for NFS as root filesystem),
54 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
56 static unsigned long nlm_grace_period;
57 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
58 static int nlm_udpport, nlm_tcpport;
61 * Constants needed for the sysctl interface.
63 static const unsigned long nlm_grace_period_min = 0;
64 static const unsigned long nlm_grace_period_max = 240;
65 static const unsigned long nlm_timeout_min = 3;
66 static const unsigned long nlm_timeout_max = 20;
67 static const int nlm_port_min = 0, nlm_port_max = 65535;
69 static struct ctl_table_header * nlm_sysctl_table;
71 static unsigned long set_grace_period(void)
73 unsigned long grace_period;
75 /* Note: nlm_timeout should always be nonzero */
77 grace_period = ((nlm_grace_period + nlm_timeout - 1)
78 / nlm_timeout) * nlm_timeout * HZ;
80 grace_period = nlm_timeout * 5 * HZ;
81 nlmsvc_grace_period = 1;
82 return grace_period + jiffies;
85 static inline void clear_grace_period(void)
87 nlmsvc_grace_period = 0;
90 nlmsvc_dispatch(struct svc_rqst *rqstp, u32 *statp)
92 struct svc_procedure *procp;
97 dprintk("nlmsvc_dispatch: vers %d proc %d\n",
98 rqstp->rq_vers, rqstp->rq_proc);
100 procp = rqstp->rq_procinfo;
101 argv = &rqstp->rq_arg.head[0];
102 resv = &rqstp->rq_res.head[0];
104 /* Decode arguments */
105 xdr = procp->pc_decode;
106 if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp)) {
107 dprintk("nlmsvc_dispatch: failed to decode arguments!\n");
108 *statp = rpc_garbage_args;
111 *statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
112 if (*statp == nlm_lck_dropit) {
113 dprintk("nlmsvc_dispatch: dropping request\n");
118 if (*statp == rpc_success && (xdr = procp->pc_encode)
119 && !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
120 dprintk("nlmsvc_dispatch: failed to encode reply\n");
121 *statp = rpc_system_err;
125 dprintk("nlmsvc_dispatch: statp %d\n", ntohl(*statp));
131 * This is the lockd kernel thread
134 lockd(struct svc_rqst *rqstp)
136 struct svc_serv *serv = rqstp->rq_server;
138 unsigned long grace_period_expire;
140 /* Lock module and set up kernel thread */
141 /* lockd_up is waiting for us to startup, so will
142 * be holding a reference to this module, so it
143 * is safe to just claim another reference
145 __module_get(THIS_MODULE);
149 * Let our maker know we're running.
151 nlmsvc_pid = current->pid;
156 /* Process request with signals blocked, but allow SIGKILL. */
157 allow_signal(SIGKILL);
162 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
165 nlm_timeout = LOCKD_DFLT_TIMEO;
166 nlmsvc_timeout = nlm_timeout * HZ;
168 grace_period_expire = set_grace_period();
171 * The main request loop. We don't terminate until the last
172 * NFS mount or NFS daemon has gone away, and we've been sent a
173 * signal, or else another process has taken over our job.
175 while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
176 long timeout = MAX_SCHEDULE_TIMEOUT;
179 flush_signals(current);
181 nlmsvc_invalidate_all();
182 grace_period_expire = set_grace_period();
187 * Retry any blocked locks that have been notified by
188 * the VFS. Don't do this during grace period.
189 * (Theoretically, there shouldn't even be blocked locks
190 * during grace period).
192 if (!nlmsvc_grace_period) {
193 timeout = nlmsvc_retry_blocked();
194 } else if (time_before(grace_period_expire, jiffies))
195 clear_grace_period();
198 * Find a socket with data available and call its
201 err = svc_recv(serv, rqstp, timeout);
202 if (err == -EAGAIN || err == -EINTR)
206 "lockd: terminating on error %d\n",
211 dprintk("lockd: request from %08x\n",
212 (unsigned)ntohl(rqstp->rq_addr.sin_addr.s_addr));
214 svc_process(serv, rqstp);
219 * Check whether there's a new lockd process before
220 * shutting down the hosts and clearing the slot.
222 if (!nlmsvc_pid || current->pid == nlmsvc_pid) {
224 nlmsvc_invalidate_all();
225 nlm_shutdown_hosts();
229 "lockd: new process, skipping host shutdown\n");
230 wake_up(&lockd_exit);
232 /* Exit the RPC thread */
233 svc_exit_thread(rqstp);
240 module_put_and_exit(0);
244 * Bring up the lockd process if it's not already up.
250 struct svc_serv * serv;
255 * Unconditionally increment the user count ... this is
256 * the number of clients who _want_ a lockd process.
260 * Check whether we're already up and running.
266 * Sanity check: if there's no pid,
267 * we should be the first user ...
269 if (nlmsvc_users > 1)
271 "lockd_up: no pid, %d users??\n", nlmsvc_users);
274 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE);
276 printk(KERN_WARNING "lockd_up: create service failed\n");
280 if ((error = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0
281 #ifdef CONFIG_NFSD_TCP
282 || (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
287 "lockd_up: makesock failed, error=%d\n", error);
288 goto destroy_and_out;
293 * Create the kernel thread and wait for it to start.
295 error = svc_create_thread(lockd, serv);
298 "lockd_up: create thread failed, error=%d\n", error);
299 goto destroy_and_out;
304 * Note: svc_serv structures have an initial use count of 1,
305 * so we exit through here on both success and failure.
315 * Decrement the user count and bring down lockd if we're the last.
329 printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
333 printk(KERN_WARNING "lockd_down: no lockd running.\n");
338 kill_proc(nlmsvc_pid, SIGKILL, 1);
340 init_waitqueue_entry(&__wait, current);
341 add_wait_queue(&lockd_exit, &__wait);
344 * Wait for the lockd process to exit, but since we're holding
345 * the lockd semaphore, we can't wait around forever ...
347 clear_thread_flag(TIF_SIGPENDING);
348 set_current_state(TASK_UNINTERRUPTIBLE);
351 schedule_timeout(HZ);
356 "lockd_down: lockd failed to exit, clearing pid\n");
359 set_current_state(TASK_RUNNING);
360 remove_wait_queue(&lockd_exit, &__wait);
362 spin_lock_irq(¤t->sighand->siglock);
364 spin_unlock_irq(¤t->sighand->siglock);
371 * Sysctl parameters (same as module parameters, different interface).
374 /* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
375 #define CTL_UNNUMBERED -2
377 static ctl_table nlm_sysctls[] = {
379 .ctl_name = CTL_UNNUMBERED,
380 .procname = "nlm_grace_period",
381 .data = &nlm_grace_period,
382 .maxlen = sizeof(int),
384 .proc_handler = &proc_doulongvec_minmax,
385 .extra1 = (unsigned long *) &nlm_grace_period_min,
386 .extra2 = (unsigned long *) &nlm_grace_period_max,
389 .ctl_name = CTL_UNNUMBERED,
390 .procname = "nlm_timeout",
391 .data = &nlm_timeout,
392 .maxlen = sizeof(int),
394 .proc_handler = &proc_doulongvec_minmax,
395 .extra1 = (unsigned long *) &nlm_timeout_min,
396 .extra2 = (unsigned long *) &nlm_timeout_max,
399 .ctl_name = CTL_UNNUMBERED,
400 .procname = "nlm_udpport",
401 .data = &nlm_udpport,
402 .maxlen = sizeof(int),
404 .proc_handler = &proc_dointvec_minmax,
405 .extra1 = (int *) &nlm_port_min,
406 .extra2 = (int *) &nlm_port_max,
409 .ctl_name = CTL_UNNUMBERED,
410 .procname = "nlm_tcpport",
411 .data = &nlm_tcpport,
412 .maxlen = sizeof(int),
414 .proc_handler = &proc_dointvec_minmax,
415 .extra1 = (int *) &nlm_port_min,
416 .extra2 = (int *) &nlm_port_max,
421 static ctl_table nlm_sysctl_dir[] = {
423 .ctl_name = CTL_UNNUMBERED,
426 .child = nlm_sysctls,
431 static ctl_table nlm_sysctl_root[] = {
436 .child = nlm_sysctl_dir,
442 * Module (and driverfs) parameters.
445 #define param_set_min_max(name, type, which_strtol, min, max) \
446 static int param_set_##name(const char *val, struct kernel_param *kp) \
449 __typeof__(type) num = which_strtol(val, &endp, 0); \
450 if (endp == val || *endp || num < (min) || num > (max)) \
452 *((int *) kp->arg) = num; \
456 param_set_min_max(port, int, simple_strtol, 0, 65535)
457 param_set_min_max(grace_period, unsigned long, simple_strtoul,
458 nlm_grace_period_min, nlm_grace_period_max)
459 param_set_min_max(timeout, unsigned long, simple_strtoul,
460 nlm_timeout_min, nlm_timeout_max)
462 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
463 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
464 MODULE_LICENSE("GPL");
466 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
467 &nlm_grace_period, 0644);
468 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
470 module_param_call(nlm_udpport, param_set_port, param_get_int,
472 module_param_call(nlm_tcpport, param_set_port, param_get_int,
476 * Initialising and terminating the module.
479 static int __init init_nlm(void)
481 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
482 return nlm_sysctl_table ? 0 : -ENOMEM;
485 static void __exit exit_nlm(void)
487 /* FIXME: delete all NLM clients */
488 nlm_shutdown_hosts();
489 unregister_sysctl_table(nlm_sysctl_table);
492 module_init(init_nlm);
493 module_exit(exit_nlm);
496 * Define NLM program and procedures
498 static struct svc_version nlmsvc_version1 = {
501 .vs_proc = nlmsvc_procedures,
502 .vs_dispatch = nlmsvc_dispatch,
503 .vs_xdrsize = NLMSVC_XDRSIZE,
505 static struct svc_version nlmsvc_version3 = {
508 .vs_proc = nlmsvc_procedures,
509 .vs_dispatch = nlmsvc_dispatch,
510 .vs_xdrsize = NLMSVC_XDRSIZE,
512 #ifdef CONFIG_LOCKD_V4
513 static struct svc_version nlmsvc_version4 = {
516 .vs_proc = nlmsvc_procedures4,
517 .vs_dispatch = nlmsvc_dispatch,
518 .vs_xdrsize = NLMSVC_XDRSIZE,
521 static struct svc_version * nlmsvc_version[] = {
522 [1] = &nlmsvc_version1,
523 [3] = &nlmsvc_version3,
524 #ifdef CONFIG_LOCKD_V4
525 [4] = &nlmsvc_version4,
529 static struct svc_stat nlmsvc_stats;
531 #define NLM_NRVERS (sizeof(nlmsvc_version)/sizeof(nlmsvc_version[0]))
532 struct svc_program nlmsvc_program = {
533 .pg_prog = NLM_PROGRAM, /* program number */
534 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
535 .pg_vers = nlmsvc_version, /* version table */
536 .pg_name = "lockd", /* service name */
537 .pg_class = "nfsd", /* share authentication with nfsd */
538 .pg_stats = &nlmsvc_stats, /* stats table */