[PATCH] knfsd: SUNRPC: Add a function to format the address in an svc_rqst for printing
[linux-2.6.git] / fs / lockd / svc.c
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
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>
27 #include <linux/mutex.h>
28
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>
38
39 #define NLMDBG_FACILITY         NLMDBG_SVC
40 #define LOCKD_BUFSIZE           (1024 + NLMSVC_XDRSIZE)
41 #define ALLOWED_SIGS            (sigmask(SIGKILL))
42
43 static struct svc_program       nlmsvc_program;
44
45 struct nlmsvc_binding *         nlmsvc_ops;
46 EXPORT_SYMBOL(nlmsvc_ops);
47
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;
54
55 static DECLARE_COMPLETION(lockd_start_done);
56 static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
57
58 /*
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
61  */
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;
66
67 /*
68  * Constants needed for the sysctl interface.
69  */
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;
75
76 static struct ctl_table_header * nlm_sysctl_table;
77
78 static unsigned long set_grace_period(void)
79 {
80         unsigned long grace_period;
81
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;
90 }
91
92 static inline void clear_grace_period(void)
93 {
94         nlmsvc_grace_period = 0;
95 }
96
97 /*
98  * This is the lockd kernel thread
99  */
100 static void
101 lockd(struct svc_rqst *rqstp)
102 {
103         int             err = 0;
104         unsigned long grace_period_expire;
105
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
110          */
111         __module_get(THIS_MODULE);
112         lock_kernel();
113
114         /*
115          * Let our maker know we're running.
116          */
117         nlmsvc_pid = current->pid;
118         nlmsvc_serv = rqstp->rq_server;
119         complete(&lockd_start_done);
120
121         daemonize("lockd");
122
123         /* Process request with signals blocked, but allow SIGKILL.  */
124         allow_signal(SIGKILL);
125
126         /* kick rpciod */
127         rpciod_up();
128
129         dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
130
131         if (!nlm_timeout)
132                 nlm_timeout = LOCKD_DFLT_TIMEO;
133         nlmsvc_timeout = nlm_timeout * HZ;
134
135         grace_period_expire = set_grace_period();
136
137         /*
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.
141          */
142         while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
143                 long timeout = MAX_SCHEDULE_TIMEOUT;
144                 char buf[RPC_MAX_ADDRBUFLEN];
145
146                 if (signalled()) {
147                         flush_signals(current);
148                         if (nlmsvc_ops) {
149                                 nlmsvc_invalidate_all();
150                                 grace_period_expire = set_grace_period();
151                         }
152                 }
153
154                 /*
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).
159                  */
160                 if (!nlmsvc_grace_period) {
161                         timeout = nlmsvc_retry_blocked();
162                 } else if (time_before(grace_period_expire, jiffies))
163                         clear_grace_period();
164
165                 /*
166                  * Find a socket with data available and call its
167                  * recvfrom routine.
168                  */
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;
177                 }
178
179                 dprintk("lockd: request from %s\n",
180                                 svc_print_addr(rqstp, buf, sizeof(buf)));
181
182                 svc_process(rqstp);
183         }
184
185         flush_signals(current);
186
187         /*
188          * Check whether there's a new lockd process before
189          * shutting down the hosts and clearing the slot.
190          */
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);
201
202         /* Exit the RPC thread */
203         svc_exit_thread(rqstp);
204
205         /* release rpciod */
206         rpciod_down();
207
208         /* Release module */
209         unlock_kernel();
210         module_put_and_exit(0);
211 }
212
213
214 static int find_socket(struct svc_serv *serv, int proto)
215 {
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;
222                 }
223         return found;
224 }
225
226 /*
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
230  */
231 static int make_socks(struct svc_serv *serv, int proto)
232 {
233         static int warned;
234         int err = 0;
235
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);
244
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;
252 }
253
254 /*
255  * Bring up the lockd process if it's not already up.
256  */
257 int
258 lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
259 {
260         struct svc_serv *       serv;
261         int                     error = 0;
262
263         mutex_lock(&nlmsvc_mutex);
264         /*
265          * Check whether we're already up and running.
266          */
267         if (nlmsvc_pid) {
268                 if (proto)
269                         error = make_socks(nlmsvc_serv, proto);
270                 goto out;
271         }
272
273         /*
274          * Sanity check: if there's no pid,
275          * we should be the first user ...
276          */
277         if (nlmsvc_users)
278                 printk(KERN_WARNING
279                         "lockd_up: no pid, %d users??\n", nlmsvc_users);
280
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;
286         }
287
288         if ((error = make_socks(serv, proto)) < 0)
289                 goto destroy_and_out;
290
291         /*
292          * Create the kernel thread and wait for it to start.
293          */
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;
299         }
300         wait_for_completion(&lockd_start_done);
301
302         /*
303          * Note: svc_serv structures have an initial use count of 1,
304          * so we exit through here on both success and failure.
305          */
306 destroy_and_out:
307         svc_destroy(serv);
308 out:
309         if (!error)
310                 nlmsvc_users++;
311         mutex_unlock(&nlmsvc_mutex);
312         return error;
313 }
314 EXPORT_SYMBOL(lockd_up);
315
316 /*
317  * Decrement the user count and bring down lockd if we're the last.
318  */
319 void
320 lockd_down(void)
321 {
322         static int warned;
323
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);
330
331         if (!nlmsvc_pid) {
332                 if (warned++ == 0)
333                         printk(KERN_WARNING "lockd_down: no lockd running.\n"); 
334                 goto out;
335         }
336         warned = 0;
337
338         kill_proc(nlmsvc_pid, SIGKILL, 1);
339         /*
340          * Wait for the lockd process to exit, but since we're holding
341          * the lockd semaphore, we can't wait around forever ...
342          */
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;
349         }
350         spin_lock_irq(&current->sighand->siglock);
351         recalc_sigpending();
352         spin_unlock_irq(&current->sighand->siglock);
353 out:
354         mutex_unlock(&nlmsvc_mutex);
355 }
356 EXPORT_SYMBOL(lockd_down);
357
358 /*
359  * Sysctl parameters (same as module parameters, different interface).
360  */
361
362 static ctl_table nlm_sysctls[] = {
363         {
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,
372         },
373         {
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,
382         },
383         {
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,
392         },
393         {
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,
402         },
403         {
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,
410         },
411         {
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,
418         },
419         { .ctl_name = 0 }
420 };
421
422 static ctl_table nlm_sysctl_dir[] = {
423         {
424                 .ctl_name       = CTL_UNNUMBERED,
425                 .procname       = "nfs",
426                 .mode           = 0555,
427                 .child          = nlm_sysctls,
428         },
429         { .ctl_name = 0 }
430 };
431
432 static ctl_table nlm_sysctl_root[] = {
433         {
434                 .ctl_name       = CTL_FS,
435                 .procname       = "fs",
436                 .mode           = 0555,
437                 .child          = nlm_sysctl_dir,
438         },
439         { .ctl_name = 0 }
440 };
441
442 /*
443  * Module (and driverfs) parameters.
444  */
445
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)   \
448 {                                                                       \
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;                                                       \
455 }
456
457 static inline int is_callback(u32 proc)
458 {
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;
466 }
467
468
469 static int lockd_authenticate(struct svc_rqst *rqstp)
470 {
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)
480                                  */
481                                 return SVC_OK;
482                         }
483                         return svc_set_client(rqstp);
484         }
485         return SVC_DENIED;
486 }
487
488
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)
494
495 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
496 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
497 MODULE_LICENSE("GPL");
498
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);
508
509 /*
510  * Initialising and terminating the module.
511  */
512
513 static int __init init_nlm(void)
514 {
515         nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
516         return nlm_sysctl_table ? 0 : -ENOMEM;
517 }
518
519 static void __exit exit_nlm(void)
520 {
521         /* FIXME: delete all NLM clients */
522         nlm_shutdown_hosts();
523         unregister_sysctl_table(nlm_sysctl_table);
524 }
525
526 module_init(init_nlm);
527 module_exit(exit_nlm);
528
529 /*
530  * Define NLM program and procedures
531  */
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,
537 };
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,
543 };
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,
550 };
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
558 };
559
560 static struct svc_stat          nlmsvc_stats;
561
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 */
571 };