blob: 0aaccb03bf769a582ce6070d7e04ecfa261ae9f8 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/nfsd/nfssvc.c
3 *
4 * Central processing for nfsd.
5 *
6 * Authors: Olaf Kirch (okir@monad.swb.de)
7 *
8 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
9 */
10
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/module.h>
12
13#include <linux/time.h>
14#include <linux/errno.h>
15#include <linux/nfs.h>
16#include <linux/in.h>
17#include <linux/uio.h>
18#include <linux/unistd.h>
19#include <linux/slab.h>
20#include <linux/smp.h>
21#include <linux/smp_lock.h>
22#include <linux/fs_struct.h>
23
24#include <linux/sunrpc/types.h>
25#include <linux/sunrpc/stats.h>
26#include <linux/sunrpc/svc.h>
27#include <linux/sunrpc/svcsock.h>
28#include <linux/sunrpc/cache.h>
29#include <linux/nfsd/nfsd.h>
30#include <linux/nfsd/stats.h>
31#include <linux/nfsd/cache.h>
NeilBrown70c3b762005-11-07 01:00:25 -080032#include <linux/nfsd/syscall.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/lockd/bind.h>
Andreas Gruenbachera257cdd2005-06-22 17:16:26 +000034#include <linux/nfsacl.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36#define NFSDDBG_FACILITY NFSDDBG_SVC
37
38/* these signals will be delivered to an nfsd thread
39 * when handling a request
40 */
41#define ALLOWED_SIGS (sigmask(SIGKILL))
42/* these signals will be delivered to an nfsd thread
43 * when not handling a request. i.e. when waiting
44 */
45#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT))
46/* if the last thread dies with SIGHUP, then the exports table is
47 * left unchanged ( like 2.4-{0-9} ). Any other signal will clear
48 * the exports table (like 2.2).
49 */
50#define SIG_NOCLEAN SIGHUP
51
52extern struct svc_program nfsd_program;
53static void nfsd(struct svc_rqst *rqstp);
54struct timeval nfssvc_boot;
NeilBrown70c3b762005-11-07 01:00:25 -080055 struct svc_serv *nfsd_serv;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056static atomic_t nfsd_busy;
57static unsigned long nfsd_last_call;
58static DEFINE_SPINLOCK(nfsd_call_lock);
59
Andreas Gruenbacher3fb803a2006-02-01 03:04:34 -080060#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
61static struct svc_stat nfsd_acl_svcstats;
62static struct svc_version * nfsd_acl_version[] = {
63 [2] = &nfsd_acl_version2,
64 [3] = &nfsd_acl_version3,
65};
66
67#define NFSD_ACL_MINVERS 2
Tobias Klausere8c96f82006-03-24 03:15:34 -080068#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
Andreas Gruenbacher3fb803a2006-02-01 03:04:34 -080069static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
70
71static struct svc_program nfsd_acl_program = {
72 .pg_prog = NFS_ACL_PROGRAM,
73 .pg_nvers = NFSD_ACL_NRVERS,
74 .pg_vers = nfsd_acl_versions,
75 .pg_name = "nfsd",
76 .pg_class = "nfsd",
77 .pg_stats = &nfsd_acl_svcstats,
78 .pg_authenticate = &svc_set_client,
79};
80
81static struct svc_stat nfsd_acl_svcstats = {
82 .program = &nfsd_acl_program,
83};
84#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
85
NeilBrown70c3b762005-11-07 01:00:25 -080086static struct svc_version * nfsd_version[] = {
87 [2] = &nfsd_version2,
88#if defined(CONFIG_NFSD_V3)
89 [3] = &nfsd_version3,
90#endif
91#if defined(CONFIG_NFSD_V4)
92 [4] = &nfsd_version4,
93#endif
94};
95
96#define NFSD_MINVERS 2
Tobias Klausere8c96f82006-03-24 03:15:34 -080097#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
NeilBrown70c3b762005-11-07 01:00:25 -080098static struct svc_version *nfsd_versions[NFSD_NRVERS];
99
100struct svc_program nfsd_program = {
Andreas Gruenbacher3fb803a2006-02-01 03:04:34 -0800101#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
102 .pg_next = &nfsd_acl_program,
103#endif
NeilBrown70c3b762005-11-07 01:00:25 -0800104 .pg_prog = NFS_PROGRAM, /* program number */
105 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
106 .pg_vers = nfsd_versions, /* version table */
107 .pg_name = "nfsd", /* program name */
108 .pg_class = "nfsd", /* authentication class */
109 .pg_stats = &nfsd_svcstats, /* version table */
110 .pg_authenticate = &svc_set_client, /* export authentication */
111
112};
113
NeilBrown6658d3a2006-10-02 02:17:46 -0700114int nfsd_vers(int vers, enum vers_op change)
115{
116 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
117 return -1;
118 switch(change) {
119 case NFSD_SET:
120 nfsd_versions[vers] = nfsd_version[vers];
121 break;
122#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
123 if (vers < NFSD_ACL_NRVERS)
124 nfsd_acl_version[vers] = nfsd_acl_version[vers];
125#endif
126 case NFSD_CLEAR:
127 nfsd_versions[vers] = NULL;
128#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
129 if (vers < NFSD_ACL_NRVERS)
130 nfsd_acl_version[vers] = NULL;
131#endif
132 break;
133 case NFSD_TEST:
134 return nfsd_versions[vers] != NULL;
135 case NFSD_AVAIL:
136 return nfsd_version[vers] != NULL;
137 }
138 return 0;
139}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140/*
141 * Maximum number of nfsd processes
142 */
143#define NFSD_MAXSERVS 8192
144
145int nfsd_nrthreads(void)
146{
147 if (nfsd_serv == NULL)
148 return 0;
149 else
150 return nfsd_serv->sv_nrthreads;
151}
152
NeilBrownbc591cc2006-10-02 02:17:44 -0700153static int killsig; /* signal that was used to kill last nfsd */
154static void nfsd_last_thread(struct svc_serv *serv)
155{
156 /* When last nfsd thread exits we need to do some clean-up */
NeilBrown24e36662006-10-02 02:17:45 -0700157 struct svc_sock *svsk;
158 list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
159 lockd_down();
NeilBrownbc591cc2006-10-02 02:17:44 -0700160 nfsd_serv = NULL;
161 nfsd_racache_shutdown();
162 nfs4_state_shutdown();
163
164 printk(KERN_WARNING "nfsd: last server has exited\n");
165 if (killsig != SIG_NOCLEAN) {
166 printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
167 nfsd_export_flush();
168 }
169}
NeilBrown6658d3a2006-10-02 02:17:46 -0700170
171void nfsd_reset_versions(void)
172{
173 int found_one = 0;
174 int i;
175
176 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
177 if (nfsd_program.pg_vers[i])
178 found_one = 1;
179 }
180
181 if (!found_one) {
182 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
183 nfsd_program.pg_vers[i] = nfsd_version[i];
184#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
185 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
186 nfsd_acl_program.pg_vers[i] =
187 nfsd_acl_version[i];
188#endif
189 }
190}
191
NeilBrownb41b66d2006-10-02 02:17:48 -0700192int nfsd_create_serv(void)
NeilBrown02a375f2006-10-02 02:17:46 -0700193{
194 int err = 0;
195 lock_kernel();
196 if (nfsd_serv) {
Greg Banks9a24ab52006-10-02 02:17:58 -0700197 svc_get(nfsd_serv);
NeilBrown02a375f2006-10-02 02:17:46 -0700198 unlock_kernel();
199 return 0;
200 }
NeilBrown596bbe52006-10-04 02:15:48 -0700201 if (nfsd_max_blksize == 0) {
202 /* choose a suitable default */
203 struct sysinfo i;
204 si_meminfo(&i);
205 /* Aim for 1/4096 of memory per thread
206 * This gives 1MB on 4Gig machines
207 * But only uses 32K on 128M machines.
208 * Bottom out at 8K on 32M and smaller.
209 * Of course, this is only a default.
210 */
211 nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
NeilBrown44c55602006-10-04 02:16:15 -0700212 i.totalram <<= PAGE_SHIFT - 12;
NeilBrown596bbe52006-10-04 02:15:48 -0700213 while (nfsd_max_blksize > i.totalram &&
214 nfsd_max_blksize >= 8*1024*2)
215 nfsd_max_blksize /= 2;
216 }
NeilBrown02a375f2006-10-02 02:17:46 -0700217
218 atomic_set(&nfsd_busy, 0);
NeilBrown596bbe52006-10-04 02:15:48 -0700219 nfsd_serv = svc_create_pooled(&nfsd_program,
NeilBrownc6b0a9f2006-10-06 00:44:05 -0700220 nfsd_max_blksize,
Greg Bankseec09662006-10-02 02:18:00 -0700221 nfsd_last_thread,
222 nfsd, SIG_NOCLEAN, THIS_MODULE);
NeilBrown02a375f2006-10-02 02:17:46 -0700223 if (nfsd_serv == NULL)
224 err = -ENOMEM;
NeilBrown02a375f2006-10-02 02:17:46 -0700225 unlock_kernel();
226 do_gettimeofday(&nfssvc_boot); /* record boot time */
227 return err;
228}
229
230static int nfsd_init_socks(int port)
231{
232 int error;
233 if (!list_empty(&nfsd_serv->sv_permsocks))
234 return 0;
235
NeilBrown02a375f2006-10-02 02:17:46 -0700236 error = lockd_up(IPPROTO_UDP);
NeilBrown4a3ae422006-10-02 02:17:53 -0700237 if (error >= 0) {
238 error = svc_makesock(nfsd_serv, IPPROTO_UDP, port);
239 if (error < 0)
240 lockd_down();
241 }
NeilBrown02a375f2006-10-02 02:17:46 -0700242 if (error < 0)
243 return error;
244
245#ifdef CONFIG_NFSD_TCP
NeilBrown02a375f2006-10-02 02:17:46 -0700246 error = lockd_up(IPPROTO_TCP);
NeilBrown4a3ae422006-10-02 02:17:53 -0700247 if (error >= 0) {
248 error = svc_makesock(nfsd_serv, IPPROTO_TCP, port);
249 if (error < 0)
250 lockd_down();
251 }
NeilBrown02a375f2006-10-02 02:17:46 -0700252 if (error < 0)
253 return error;
254#endif
255 return 0;
256}
257
Greg Bankseed29652006-10-02 02:18:02 -0700258int nfsd_nrpools(void)
259{
260 if (nfsd_serv == NULL)
261 return 0;
262 else
263 return nfsd_serv->sv_nrpools;
264}
265
266int nfsd_get_nrthreads(int n, int *nthreads)
267{
268 int i = 0;
269
270 if (nfsd_serv != NULL) {
271 for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
272 nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
273 }
274
275 return 0;
276}
277
278int nfsd_set_nrthreads(int n, int *nthreads)
279{
280 int i = 0;
281 int tot = 0;
282 int err = 0;
283
284 if (nfsd_serv == NULL || n <= 0)
285 return 0;
286
287 if (n > nfsd_serv->sv_nrpools)
288 n = nfsd_serv->sv_nrpools;
289
290 /* enforce a global maximum number of threads */
291 tot = 0;
292 for (i = 0; i < n; i++) {
293 if (nthreads[i] > NFSD_MAXSERVS)
294 nthreads[i] = NFSD_MAXSERVS;
295 tot += nthreads[i];
296 }
297 if (tot > NFSD_MAXSERVS) {
298 /* total too large: scale down requested numbers */
299 for (i = 0; i < n && tot > 0; i++) {
300 int new = nthreads[i] * NFSD_MAXSERVS / tot;
301 tot -= (nthreads[i] - new);
302 nthreads[i] = new;
303 }
304 for (i = 0; i < n && tot > 0; i++) {
305 nthreads[i]--;
306 tot--;
307 }
308 }
309
310 /*
311 * There must always be a thread in pool 0; the admin
312 * can't shut down NFS completely using pool_threads.
313 */
314 if (nthreads[0] == 0)
315 nthreads[0] = 1;
316
317 /* apply the new numbers */
318 lock_kernel();
319 svc_get(nfsd_serv);
320 for (i = 0; i < n; i++) {
321 err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
322 nthreads[i]);
323 if (err)
324 break;
325 }
326 svc_destroy(nfsd_serv);
327 unlock_kernel();
328
329 return err;
330}
331
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332int
333nfsd_svc(unsigned short port, int nrservs)
334{
335 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
337 lock_kernel();
NeilBrown6658d3a2006-10-02 02:17:46 -0700338 dprintk("nfsd: creating service\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 error = -EINVAL;
340 if (nrservs <= 0)
341 nrservs = 0;
342 if (nrservs > NFSD_MAXSERVS)
343 nrservs = NFSD_MAXSERVS;
344
345 /* Readahead param cache - will no-op if it already exists */
346 error = nfsd_racache_init(2*nrservs);
347 if (error<0)
348 goto out;
NeilBrown76a35502005-06-23 22:03:26 -0700349 error = nfs4_state_start();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 if (error<0)
351 goto out;
Andreas Gruenbacher3fb803a2006-02-01 03:04:34 -0800352
NeilBrown02a375f2006-10-02 02:17:46 -0700353 nfsd_reset_versions();
354
355 error = nfsd_create_serv();
356
357 if (error)
358 goto out;
359 error = nfsd_init_socks(port);
360 if (error)
361 goto failure;
362
Greg Bankseec09662006-10-02 02:18:00 -0700363 error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 failure:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 svc_destroy(nfsd_serv); /* Release server */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 out:
367 unlock_kernel();
368 return error;
369}
370
371static inline void
372update_thread_usage(int busy_threads)
373{
374 unsigned long prev_call;
375 unsigned long diff;
376 int decile;
377
378 spin_lock(&nfsd_call_lock);
379 prev_call = nfsd_last_call;
380 nfsd_last_call = jiffies;
381 decile = busy_threads*10/nfsdstats.th_cnt;
382 if (decile>0 && decile <= 10) {
383 diff = nfsd_last_call - prev_call;
384 if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP)
385 nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP;
386 if (decile == 10)
387 nfsdstats.th_fullcnt++;
388 }
389 spin_unlock(&nfsd_call_lock);
390}
391
392/*
393 * This is the NFS server kernel thread
394 */
395static void
396nfsd(struct svc_rqst *rqstp)
397{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 struct fs_struct *fsp;
399 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 sigset_t shutdown_mask, allowed_mask;
401
402 /* Lock module and set up kernel thread */
403 lock_kernel();
404 daemonize("nfsd");
405
406 /* After daemonize() this kernel thread shares current->fs
407 * with the init process. We need to create files with a
408 * umask of 0 instead of init's umask. */
409 fsp = copy_fs_struct(current->fs);
410 if (!fsp) {
411 printk("Unable to start nfsd thread: out of memory\n");
412 goto out;
413 }
414 exit_fs(current);
415 current->fs = fsp;
416 current->fs->umask = 0;
417
418 siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);
419 siginitsetinv(&allowed_mask, ALLOWED_SIGS);
420
421 nfsdstats.th_cnt++;
422
Greg Bankseec09662006-10-02 02:18:00 -0700423 rqstp->rq_task = current;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424
425 unlock_kernel();
426
427 /*
428 * We want less throttling in balance_dirty_pages() so that nfs to
429 * localhost doesn't cause nfsd to lock up due to all the client's
430 * dirty pages.
431 */
432 current->flags |= PF_LESS_THROTTLE;
433
434 /*
435 * The main request loop
436 */
437 for (;;) {
438 /* Block all but the shutdown signals */
439 sigprocmask(SIG_SETMASK, &shutdown_mask, NULL);
440
441 /*
442 * Find a socket with data available and call its
443 * recvfrom routine.
444 */
NeilBrown6fb2b472006-10-02 02:17:50 -0700445 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 ;
447 if (err < 0)
448 break;
449 update_thread_usage(atomic_read(&nfsd_busy));
450 atomic_inc(&nfsd_busy);
451
452 /* Lock the export hash tables for reading. */
453 exp_readlock();
454
455 /* Process request with signals blocked. */
456 sigprocmask(SIG_SETMASK, &allowed_mask, NULL);
457
NeilBrown6fb2b472006-10-02 02:17:50 -0700458 svc_process(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
460 /* Unlock export hash tables */
461 exp_readunlock();
462 update_thread_usage(atomic_read(&nfsd_busy));
463 atomic_dec(&nfsd_busy);
464 }
465
466 if (err != -EINTR) {
467 printk(KERN_WARNING "nfsd: terminating on error %d\n", -err);
468 } else {
469 unsigned int signo;
470
471 for (signo = 1; signo <= _NSIG; signo++)
472 if (sigismember(&current->pending.signal, signo) &&
473 !sigismember(&current->blocked, signo))
474 break;
NeilBrownbc591cc2006-10-02 02:17:44 -0700475 killsig = signo;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 }
NeilBrown24e36662006-10-02 02:17:45 -0700477 /* Clear signals before calling svc_exit_thread() */
NeilBrown9e4160522005-04-16 15:26:37 -0700478 flush_signals(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
480 lock_kernel();
481
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 nfsdstats.th_cnt --;
483
484out:
485 /* Release the thread */
486 svc_exit_thread(rqstp);
487
488 /* Release module */
Steven Rostedtc4f92db2005-08-17 14:25:23 -0400489 unlock_kernel();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 module_put_and_exit(0);
491}
492
493int
Al Viroc7afef12006-10-19 23:29:02 -0700494nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495{
496 struct svc_procedure *proc;
497 kxdrproc_t xdr;
Al Viroad451d32006-10-19 23:28:55 -0700498 __be32 nfserr;
499 __be32 *nfserrp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500
501 dprintk("nfsd_dispatch: vers %d proc %d\n",
502 rqstp->rq_vers, rqstp->rq_proc);
503 proc = rqstp->rq_procinfo;
504
505 /* Check whether we have this call in the cache. */
506 switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) {
507 case RC_INTR:
508 case RC_DROPIT:
509 return 0;
510 case RC_REPLY:
511 return 1;
512 case RC_DOIT:;
513 /* do it */
514 }
515
516 /* Decode arguments */
517 xdr = proc->pc_decode;
Al Viroad451d32006-10-19 23:28:55 -0700518 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 rqstp->rq_argp)) {
520 dprintk("nfsd: failed to decode arguments!\n");
521 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
522 *statp = rpc_garbage_args;
523 return 1;
524 }
525
526 /* need to grab the location to store the status, as
527 * nfsv4 does some encoding while processing
528 */
529 nfserrp = rqstp->rq_res.head[0].iov_base
530 + rqstp->rq_res.head[0].iov_len;
Al Viroad451d32006-10-19 23:28:55 -0700531 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532
533 /* Now call the procedure handler, and encode NFS status. */
534 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
535 if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2)
536 nfserr = nfserr_dropit;
537 if (nfserr == nfserr_dropit) {
538 dprintk("nfsd: Dropping request due to malloc failure!\n");
539 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
540 return 0;
541 }
542
543 if (rqstp->rq_proc != 0)
544 *nfserrp++ = nfserr;
545
546 /* Encode result.
547 * For NFSv2, additional info is never returned in case of an error.
548 */
549 if (!(nfserr && rqstp->rq_vers == 2)) {
550 xdr = proc->pc_encode;
551 if (xdr && !xdr(rqstp, nfserrp,
552 rqstp->rq_resp)) {
553 /* Failed to encode result. Release cache entry */
554 dprintk("nfsd: failed to encode result!\n");
555 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
556 *statp = rpc_system_err;
557 return 1;
558 }
559 }
560
561 /* Store reply in cache. */
562 nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
563 return 1;
564}