Loading...
1/*
2 * Central processing for nfsd.
3 *
4 * Authors: Olaf Kirch (okir@monad.swb.de)
5 *
6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
7 */
8
9#include <linux/sched.h>
10#include <linux/freezer.h>
11#include <linux/module.h>
12#include <linux/fs_struct.h>
13#include <linux/swap.h>
14
15#include <linux/sunrpc/stats.h>
16#include <linux/sunrpc/svcsock.h>
17#include <linux/lockd/bind.h>
18#include <linux/nfsacl.h>
19#include <linux/seq_file.h>
20#include <net/net_namespace.h>
21#include "nfsd.h"
22#include "cache.h"
23#include "vfs.h"
24#include "netns.h"
25
26#define NFSDDBG_FACILITY NFSDDBG_SVC
27
28extern struct svc_program nfsd_program;
29static int nfsd(void *vrqstp);
30
31/*
32 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
33 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
34 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
35 *
36 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
37 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
38 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
39 * entry of ->sv_pools[].
40 *
41 * Transitions of the thread count between zero and non-zero are of particular
42 * interest since the svc_serv needs to be created and initialized at that
43 * point, or freed.
44 *
45 * Finally, the nfsd_mutex also protects some of the global variables that are
46 * accessed when nfsd starts and that are settable via the write_* routines in
47 * nfsctl.c. In particular:
48 *
49 * user_recovery_dirname
50 * user_lease_time
51 * nfsd_versions
52 */
53DEFINE_MUTEX(nfsd_mutex);
54
55/*
56 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
57 * nfsd_drc_max_pages limits the total amount of memory available for
58 * version 4.1 DRC caches.
59 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
60 */
61spinlock_t nfsd_drc_lock;
62unsigned long nfsd_drc_max_mem;
63unsigned long nfsd_drc_mem_used;
64
65#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
66static struct svc_stat nfsd_acl_svcstats;
67static struct svc_version * nfsd_acl_version[] = {
68 [2] = &nfsd_acl_version2,
69 [3] = &nfsd_acl_version3,
70};
71
72#define NFSD_ACL_MINVERS 2
73#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
74static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
75
76static struct svc_program nfsd_acl_program = {
77 .pg_prog = NFS_ACL_PROGRAM,
78 .pg_nvers = NFSD_ACL_NRVERS,
79 .pg_vers = nfsd_acl_versions,
80 .pg_name = "nfsacl",
81 .pg_class = "nfsd",
82 .pg_stats = &nfsd_acl_svcstats,
83 .pg_authenticate = &svc_set_client,
84};
85
86static struct svc_stat nfsd_acl_svcstats = {
87 .program = &nfsd_acl_program,
88};
89#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
90
91static struct svc_version * nfsd_version[] = {
92 [2] = &nfsd_version2,
93#if defined(CONFIG_NFSD_V3)
94 [3] = &nfsd_version3,
95#endif
96#if defined(CONFIG_NFSD_V4)
97 [4] = &nfsd_version4,
98#endif
99};
100
101#define NFSD_MINVERS 2
102#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
103static struct svc_version *nfsd_versions[NFSD_NRVERS];
104
105struct svc_program nfsd_program = {
106#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
107 .pg_next = &nfsd_acl_program,
108#endif
109 .pg_prog = NFS_PROGRAM, /* program number */
110 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
111 .pg_vers = nfsd_versions, /* version table */
112 .pg_name = "nfsd", /* program name */
113 .pg_class = "nfsd", /* authentication class */
114 .pg_stats = &nfsd_svcstats, /* version table */
115 .pg_authenticate = &svc_set_client, /* export authentication */
116
117};
118
119static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = {
120 [0] = 1,
121 [1] = 1,
122};
123
124int nfsd_vers(int vers, enum vers_op change)
125{
126 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
127 return 0;
128 switch(change) {
129 case NFSD_SET:
130 nfsd_versions[vers] = nfsd_version[vers];
131#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
132 if (vers < NFSD_ACL_NRVERS)
133 nfsd_acl_versions[vers] = nfsd_acl_version[vers];
134#endif
135 break;
136 case NFSD_CLEAR:
137 nfsd_versions[vers] = NULL;
138#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
139 if (vers < NFSD_ACL_NRVERS)
140 nfsd_acl_versions[vers] = NULL;
141#endif
142 break;
143 case NFSD_TEST:
144 return nfsd_versions[vers] != NULL;
145 case NFSD_AVAIL:
146 return nfsd_version[vers] != NULL;
147 }
148 return 0;
149}
150
151int nfsd_minorversion(u32 minorversion, enum vers_op change)
152{
153 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION)
154 return -1;
155 switch(change) {
156 case NFSD_SET:
157 nfsd_supported_minorversions[minorversion] = true;
158 break;
159 case NFSD_CLEAR:
160 nfsd_supported_minorversions[minorversion] = false;
161 break;
162 case NFSD_TEST:
163 return nfsd_supported_minorversions[minorversion];
164 case NFSD_AVAIL:
165 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
166 }
167 return 0;
168}
169
170/*
171 * Maximum number of nfsd processes
172 */
173#define NFSD_MAXSERVS 8192
174
175int nfsd_nrthreads(struct net *net)
176{
177 int rv = 0;
178 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
179
180 mutex_lock(&nfsd_mutex);
181 if (nn->nfsd_serv)
182 rv = nn->nfsd_serv->sv_nrthreads;
183 mutex_unlock(&nfsd_mutex);
184 return rv;
185}
186
187static int nfsd_init_socks(struct net *net)
188{
189 int error;
190 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
191
192 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
193 return 0;
194
195 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
196 SVC_SOCK_DEFAULTS);
197 if (error < 0)
198 return error;
199
200 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
201 SVC_SOCK_DEFAULTS);
202 if (error < 0)
203 return error;
204
205 return 0;
206}
207
208static int nfsd_users = 0;
209
210static int nfsd_startup_generic(int nrservs)
211{
212 int ret;
213
214 if (nfsd_users++)
215 return 0;
216
217 /*
218 * Readahead param cache - will no-op if it already exists.
219 * (Note therefore results will be suboptimal if number of
220 * threads is modified after nfsd start.)
221 */
222 ret = nfsd_racache_init(2*nrservs);
223 if (ret)
224 return ret;
225 ret = nfs4_state_start();
226 if (ret)
227 goto out_racache;
228 return 0;
229
230out_racache:
231 nfsd_racache_shutdown();
232 return ret;
233}
234
235static void nfsd_shutdown_generic(void)
236{
237 if (--nfsd_users)
238 return;
239
240 nfs4_state_shutdown();
241 nfsd_racache_shutdown();
242}
243
244static bool nfsd_needs_lockd(void)
245{
246#if defined(CONFIG_NFSD_V3)
247 return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
248#else
249 return (nfsd_versions[2] != NULL);
250#endif
251}
252
253static int nfsd_startup_net(int nrservs, struct net *net)
254{
255 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
256 int ret;
257
258 if (nn->nfsd_net_up)
259 return 0;
260
261 ret = nfsd_startup_generic(nrservs);
262 if (ret)
263 return ret;
264 ret = nfsd_init_socks(net);
265 if (ret)
266 goto out_socks;
267
268 if (nfsd_needs_lockd() && !nn->lockd_up) {
269 ret = lockd_up(net);
270 if (ret)
271 goto out_socks;
272 nn->lockd_up = 1;
273 }
274
275 ret = nfs4_state_start_net(net);
276 if (ret)
277 goto out_lockd;
278
279 nn->nfsd_net_up = true;
280 return 0;
281
282out_lockd:
283 if (nn->lockd_up) {
284 lockd_down(net);
285 nn->lockd_up = 0;
286 }
287out_socks:
288 nfsd_shutdown_generic();
289 return ret;
290}
291
292static void nfsd_shutdown_net(struct net *net)
293{
294 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
295
296 nfs4_state_shutdown_net(net);
297 if (nn->lockd_up) {
298 lockd_down(net);
299 nn->lockd_up = 0;
300 }
301 nn->nfsd_net_up = false;
302 nfsd_shutdown_generic();
303}
304
305static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
306{
307 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
308
309 /*
310 * write_ports can create the server without actually starting
311 * any threads--if we get shut down before any threads are
312 * started, then nfsd_last_thread will be run before any of this
313 * other initialization has been done.
314 */
315 if (!nn->nfsd_net_up)
316 return;
317 nfsd_shutdown_net(net);
318
319 svc_rpcb_cleanup(serv, net);
320
321 printk(KERN_WARNING "nfsd: last server has exited, flushing export "
322 "cache\n");
323 nfsd_export_flush(net);
324}
325
326void nfsd_reset_versions(void)
327{
328 int found_one = 0;
329 int i;
330
331 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
332 if (nfsd_program.pg_vers[i])
333 found_one = 1;
334 }
335
336 if (!found_one) {
337 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
338 nfsd_program.pg_vers[i] = nfsd_version[i];
339#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
340 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
341 nfsd_acl_program.pg_vers[i] =
342 nfsd_acl_version[i];
343#endif
344 }
345}
346
347/*
348 * Each session guarantees a negotiated per slot memory cache for replies
349 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
350 * NFSv4.1 server might want to use more memory for a DRC than a machine
351 * with mutiple services.
352 *
353 * Impose a hard limit on the number of pages for the DRC which varies
354 * according to the machines free pages. This is of course only a default.
355 *
356 * For now this is a #defined shift which could be under admin control
357 * in the future.
358 */
359static void set_max_drc(void)
360{
361 #define NFSD_DRC_SIZE_SHIFT 10
362 nfsd_drc_max_mem = (nr_free_buffer_pages()
363 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
364 nfsd_drc_mem_used = 0;
365 spin_lock_init(&nfsd_drc_lock);
366 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
367}
368
369static int nfsd_get_default_max_blksize(void)
370{
371 struct sysinfo i;
372 unsigned long long target;
373 unsigned long ret;
374
375 si_meminfo(&i);
376 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
377 /*
378 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
379 * machines, but only uses 32K on 128M machines. Bottom out at
380 * 8K on 32M and smaller. Of course, this is only a default.
381 */
382 target >>= 12;
383
384 ret = NFSSVC_MAXBLKSIZE;
385 while (ret > target && ret >= 8*1024*2)
386 ret /= 2;
387 return ret;
388}
389
390int nfsd_create_serv(struct net *net)
391{
392 int error;
393 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
394
395 WARN_ON(!mutex_is_locked(&nfsd_mutex));
396 if (nn->nfsd_serv) {
397 svc_get(nn->nfsd_serv);
398 return 0;
399 }
400 if (nfsd_max_blksize == 0)
401 nfsd_max_blksize = nfsd_get_default_max_blksize();
402 nfsd_reset_versions();
403 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
404 nfsd_last_thread, nfsd, THIS_MODULE);
405 if (nn->nfsd_serv == NULL)
406 return -ENOMEM;
407
408 error = svc_bind(nn->nfsd_serv, net);
409 if (error < 0) {
410 svc_destroy(nn->nfsd_serv);
411 return error;
412 }
413
414 set_max_drc();
415 do_gettimeofday(&nn->nfssvc_boot); /* record boot time */
416 return 0;
417}
418
419int nfsd_nrpools(struct net *net)
420{
421 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
422
423 if (nn->nfsd_serv == NULL)
424 return 0;
425 else
426 return nn->nfsd_serv->sv_nrpools;
427}
428
429int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
430{
431 int i = 0;
432 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
433
434 if (nn->nfsd_serv != NULL) {
435 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
436 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
437 }
438
439 return 0;
440}
441
442void nfsd_destroy(struct net *net)
443{
444 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
445 int destroy = (nn->nfsd_serv->sv_nrthreads == 1);
446
447 if (destroy)
448 svc_shutdown_net(nn->nfsd_serv, net);
449 svc_destroy(nn->nfsd_serv);
450 if (destroy)
451 nn->nfsd_serv = NULL;
452}
453
454int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
455{
456 int i = 0;
457 int tot = 0;
458 int err = 0;
459 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
460
461 WARN_ON(!mutex_is_locked(&nfsd_mutex));
462
463 if (nn->nfsd_serv == NULL || n <= 0)
464 return 0;
465
466 if (n > nn->nfsd_serv->sv_nrpools)
467 n = nn->nfsd_serv->sv_nrpools;
468
469 /* enforce a global maximum number of threads */
470 tot = 0;
471 for (i = 0; i < n; i++) {
472 if (nthreads[i] > NFSD_MAXSERVS)
473 nthreads[i] = NFSD_MAXSERVS;
474 tot += nthreads[i];
475 }
476 if (tot > NFSD_MAXSERVS) {
477 /* total too large: scale down requested numbers */
478 for (i = 0; i < n && tot > 0; i++) {
479 int new = nthreads[i] * NFSD_MAXSERVS / tot;
480 tot -= (nthreads[i] - new);
481 nthreads[i] = new;
482 }
483 for (i = 0; i < n && tot > 0; i++) {
484 nthreads[i]--;
485 tot--;
486 }
487 }
488
489 /*
490 * There must always be a thread in pool 0; the admin
491 * can't shut down NFS completely using pool_threads.
492 */
493 if (nthreads[0] == 0)
494 nthreads[0] = 1;
495
496 /* apply the new numbers */
497 svc_get(nn->nfsd_serv);
498 for (i = 0; i < n; i++) {
499 err = svc_set_num_threads(nn->nfsd_serv, &nn->nfsd_serv->sv_pools[i],
500 nthreads[i]);
501 if (err)
502 break;
503 }
504 nfsd_destroy(net);
505 return err;
506}
507
508/*
509 * Adjust the number of threads and return the new number of threads.
510 * This is also the function that starts the server if necessary, if
511 * this is the first time nrservs is nonzero.
512 */
513int
514nfsd_svc(int nrservs, struct net *net)
515{
516 int error;
517 bool nfsd_up_before;
518 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
519
520 mutex_lock(&nfsd_mutex);
521 dprintk("nfsd: creating service\n");
522 if (nrservs <= 0)
523 nrservs = 0;
524 if (nrservs > NFSD_MAXSERVS)
525 nrservs = NFSD_MAXSERVS;
526 error = 0;
527 if (nrservs == 0 && nn->nfsd_serv == NULL)
528 goto out;
529
530 error = nfsd_create_serv(net);
531 if (error)
532 goto out;
533
534 nfsd_up_before = nn->nfsd_net_up;
535
536 error = nfsd_startup_net(nrservs, net);
537 if (error)
538 goto out_destroy;
539 error = svc_set_num_threads(nn->nfsd_serv, NULL, nrservs);
540 if (error)
541 goto out_shutdown;
542 /* We are holding a reference to nn->nfsd_serv which
543 * we don't want to count in the return value,
544 * so subtract 1
545 */
546 error = nn->nfsd_serv->sv_nrthreads - 1;
547out_shutdown:
548 if (error < 0 && !nfsd_up_before)
549 nfsd_shutdown_net(net);
550out_destroy:
551 nfsd_destroy(net); /* Release server */
552out:
553 mutex_unlock(&nfsd_mutex);
554 return error;
555}
556
557
558/*
559 * This is the NFS server kernel thread
560 */
561static int
562nfsd(void *vrqstp)
563{
564 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
565 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
566 struct net *net = perm_sock->xpt_net;
567 int err;
568
569 /* Lock module and set up kernel thread */
570 mutex_lock(&nfsd_mutex);
571
572 /* At this point, the thread shares current->fs
573 * with the init process. We need to create files with a
574 * umask of 0 instead of init's umask. */
575 if (unshare_fs_struct() < 0) {
576 printk("Unable to start nfsd thread: out of memory\n");
577 goto out;
578 }
579
580 current->fs->umask = 0;
581
582 /*
583 * thread is spawned with all signals set to SIG_IGN, re-enable
584 * the ones that will bring down the thread
585 */
586 allow_signal(SIGKILL);
587 allow_signal(SIGHUP);
588 allow_signal(SIGINT);
589 allow_signal(SIGQUIT);
590
591 nfsdstats.th_cnt++;
592 mutex_unlock(&nfsd_mutex);
593
594 /*
595 * We want less throttling in balance_dirty_pages() so that nfs to
596 * localhost doesn't cause nfsd to lock up due to all the client's
597 * dirty pages.
598 */
599 current->flags |= PF_LESS_THROTTLE;
600 set_freezable();
601
602 /*
603 * The main request loop
604 */
605 for (;;) {
606 /*
607 * Find a socket with data available and call its
608 * recvfrom routine.
609 */
610 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
611 ;
612 if (err == -EINTR)
613 break;
614 validate_process_creds();
615 svc_process(rqstp);
616 validate_process_creds();
617 }
618
619 /* Clear signals before calling svc_exit_thread() */
620 flush_signals(current);
621
622 mutex_lock(&nfsd_mutex);
623 nfsdstats.th_cnt --;
624
625out:
626 rqstp->rq_server = NULL;
627
628 /* Release the thread */
629 svc_exit_thread(rqstp);
630
631 nfsd_destroy(net);
632
633 /* Release module */
634 mutex_unlock(&nfsd_mutex);
635 module_put_and_exit(0);
636 return 0;
637}
638
639static __be32 map_new_errors(u32 vers, __be32 nfserr)
640{
641 if (nfserr == nfserr_jukebox && vers == 2)
642 return nfserr_dropit;
643 if (nfserr == nfserr_wrongsec && vers < 4)
644 return nfserr_acces;
645 return nfserr;
646}
647
648int
649nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
650{
651 struct svc_procedure *proc;
652 kxdrproc_t xdr;
653 __be32 nfserr;
654 __be32 *nfserrp;
655
656 dprintk("nfsd_dispatch: vers %d proc %d\n",
657 rqstp->rq_vers, rqstp->rq_proc);
658 proc = rqstp->rq_procinfo;
659
660 /*
661 * Give the xdr decoder a chance to change this if it wants
662 * (necessary in the NFSv4.0 compound case)
663 */
664 rqstp->rq_cachetype = proc->pc_cachetype;
665 /* Decode arguments */
666 xdr = proc->pc_decode;
667 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
668 rqstp->rq_argp)) {
669 dprintk("nfsd: failed to decode arguments!\n");
670 *statp = rpc_garbage_args;
671 return 1;
672 }
673
674 /* Check whether we have this call in the cache. */
675 switch (nfsd_cache_lookup(rqstp)) {
676 case RC_DROPIT:
677 return 0;
678 case RC_REPLY:
679 return 1;
680 case RC_DOIT:;
681 /* do it */
682 }
683
684 /* need to grab the location to store the status, as
685 * nfsv4 does some encoding while processing
686 */
687 nfserrp = rqstp->rq_res.head[0].iov_base
688 + rqstp->rq_res.head[0].iov_len;
689 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
690
691 /* Now call the procedure handler, and encode NFS status. */
692 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
693 nfserr = map_new_errors(rqstp->rq_vers, nfserr);
694 if (nfserr == nfserr_dropit || rqstp->rq_dropme) {
695 dprintk("nfsd: Dropping request; may be revisited later\n");
696 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
697 return 0;
698 }
699
700 if (rqstp->rq_proc != 0)
701 *nfserrp++ = nfserr;
702
703 /* Encode result.
704 * For NFSv2, additional info is never returned in case of an error.
705 */
706 if (!(nfserr && rqstp->rq_vers == 2)) {
707 xdr = proc->pc_encode;
708 if (xdr && !xdr(rqstp, nfserrp,
709 rqstp->rq_resp)) {
710 /* Failed to encode result. Release cache entry */
711 dprintk("nfsd: failed to encode result!\n");
712 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
713 *statp = rpc_system_err;
714 return 1;
715 }
716 }
717
718 /* Store reply in cache. */
719 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
720 return 1;
721}
722
723int nfsd_pool_stats_open(struct inode *inode, struct file *file)
724{
725 int ret;
726 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
727
728 mutex_lock(&nfsd_mutex);
729 if (nn->nfsd_serv == NULL) {
730 mutex_unlock(&nfsd_mutex);
731 return -ENODEV;
732 }
733 /* bump up the psudo refcount while traversing */
734 svc_get(nn->nfsd_serv);
735 ret = svc_pool_stats_open(nn->nfsd_serv, file);
736 mutex_unlock(&nfsd_mutex);
737 return ret;
738}
739
740int nfsd_pool_stats_release(struct inode *inode, struct file *file)
741{
742 int ret = seq_release(inode, file);
743 struct net *net = inode->i_sb->s_fs_info;
744
745 mutex_lock(&nfsd_mutex);
746 /* this function really, really should have been called svc_put() */
747 nfsd_destroy(net);
748 mutex_unlock(&nfsd_mutex);
749 return ret;
750}
1/*
2 * Central processing for nfsd.
3 *
4 * Authors: Olaf Kirch (okir@monad.swb.de)
5 *
6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
7 */
8
9#include <linux/sched.h>
10#include <linux/freezer.h>
11#include <linux/module.h>
12#include <linux/fs_struct.h>
13#include <linux/swap.h>
14
15#include <linux/sunrpc/stats.h>
16#include <linux/sunrpc/svcsock.h>
17#include <linux/sunrpc/svc_xprt.h>
18#include <linux/lockd/bind.h>
19#include <linux/nfsacl.h>
20#include <linux/seq_file.h>
21#include <linux/inetdevice.h>
22#include <net/addrconf.h>
23#include <net/ipv6.h>
24#include <net/net_namespace.h>
25#include "nfsd.h"
26#include "cache.h"
27#include "vfs.h"
28#include "netns.h"
29
30#define NFSDDBG_FACILITY NFSDDBG_SVC
31
32extern struct svc_program nfsd_program;
33static int nfsd(void *vrqstp);
34
35/*
36 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
37 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
38 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
39 *
40 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
41 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
42 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
43 * entry of ->sv_pools[].
44 *
45 * Transitions of the thread count between zero and non-zero are of particular
46 * interest since the svc_serv needs to be created and initialized at that
47 * point, or freed.
48 *
49 * Finally, the nfsd_mutex also protects some of the global variables that are
50 * accessed when nfsd starts and that are settable via the write_* routines in
51 * nfsctl.c. In particular:
52 *
53 * user_recovery_dirname
54 * user_lease_time
55 * nfsd_versions
56 */
57DEFINE_MUTEX(nfsd_mutex);
58
59/*
60 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
61 * nfsd_drc_max_pages limits the total amount of memory available for
62 * version 4.1 DRC caches.
63 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
64 */
65spinlock_t nfsd_drc_lock;
66unsigned long nfsd_drc_max_mem;
67unsigned long nfsd_drc_mem_used;
68
69#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
70static struct svc_stat nfsd_acl_svcstats;
71static struct svc_version * nfsd_acl_version[] = {
72 [2] = &nfsd_acl_version2,
73 [3] = &nfsd_acl_version3,
74};
75
76#define NFSD_ACL_MINVERS 2
77#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
78static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
79
80static struct svc_program nfsd_acl_program = {
81 .pg_prog = NFS_ACL_PROGRAM,
82 .pg_nvers = NFSD_ACL_NRVERS,
83 .pg_vers = nfsd_acl_versions,
84 .pg_name = "nfsacl",
85 .pg_class = "nfsd",
86 .pg_stats = &nfsd_acl_svcstats,
87 .pg_authenticate = &svc_set_client,
88};
89
90static struct svc_stat nfsd_acl_svcstats = {
91 .program = &nfsd_acl_program,
92};
93#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
94
95static struct svc_version * nfsd_version[] = {
96 [2] = &nfsd_version2,
97#if defined(CONFIG_NFSD_V3)
98 [3] = &nfsd_version3,
99#endif
100#if defined(CONFIG_NFSD_V4)
101 [4] = &nfsd_version4,
102#endif
103};
104
105#define NFSD_MINVERS 2
106#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
107static struct svc_version *nfsd_versions[NFSD_NRVERS];
108
109struct svc_program nfsd_program = {
110#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
111 .pg_next = &nfsd_acl_program,
112#endif
113 .pg_prog = NFS_PROGRAM, /* program number */
114 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
115 .pg_vers = nfsd_versions, /* version table */
116 .pg_name = "nfsd", /* program name */
117 .pg_class = "nfsd", /* authentication class */
118 .pg_stats = &nfsd_svcstats, /* version table */
119 .pg_authenticate = &svc_set_client, /* export authentication */
120
121};
122
123static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = {
124 [0] = 1,
125 [1] = 1,
126 [2] = 1,
127};
128
129int nfsd_vers(int vers, enum vers_op change)
130{
131 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
132 return 0;
133 switch(change) {
134 case NFSD_SET:
135 nfsd_versions[vers] = nfsd_version[vers];
136#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
137 if (vers < NFSD_ACL_NRVERS)
138 nfsd_acl_versions[vers] = nfsd_acl_version[vers];
139#endif
140 break;
141 case NFSD_CLEAR:
142 nfsd_versions[vers] = NULL;
143#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
144 if (vers < NFSD_ACL_NRVERS)
145 nfsd_acl_versions[vers] = NULL;
146#endif
147 break;
148 case NFSD_TEST:
149 return nfsd_versions[vers] != NULL;
150 case NFSD_AVAIL:
151 return nfsd_version[vers] != NULL;
152 }
153 return 0;
154}
155
156int nfsd_minorversion(u32 minorversion, enum vers_op change)
157{
158 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION)
159 return -1;
160 switch(change) {
161 case NFSD_SET:
162 nfsd_supported_minorversions[minorversion] = true;
163 break;
164 case NFSD_CLEAR:
165 nfsd_supported_minorversions[minorversion] = false;
166 break;
167 case NFSD_TEST:
168 return nfsd_supported_minorversions[minorversion];
169 case NFSD_AVAIL:
170 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
171 }
172 return 0;
173}
174
175/*
176 * Maximum number of nfsd processes
177 */
178#define NFSD_MAXSERVS 8192
179
180int nfsd_nrthreads(struct net *net)
181{
182 int rv = 0;
183 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
184
185 mutex_lock(&nfsd_mutex);
186 if (nn->nfsd_serv)
187 rv = nn->nfsd_serv->sv_nrthreads;
188 mutex_unlock(&nfsd_mutex);
189 return rv;
190}
191
192static int nfsd_init_socks(struct net *net)
193{
194 int error;
195 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
196
197 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
198 return 0;
199
200 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
201 SVC_SOCK_DEFAULTS);
202 if (error < 0)
203 return error;
204
205 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
206 SVC_SOCK_DEFAULTS);
207 if (error < 0)
208 return error;
209
210 return 0;
211}
212
213static int nfsd_users = 0;
214
215static int nfsd_startup_generic(int nrservs)
216{
217 int ret;
218
219 if (nfsd_users++)
220 return 0;
221
222 /*
223 * Readahead param cache - will no-op if it already exists.
224 * (Note therefore results will be suboptimal if number of
225 * threads is modified after nfsd start.)
226 */
227 ret = nfsd_racache_init(2*nrservs);
228 if (ret)
229 goto dec_users;
230
231 ret = nfs4_state_start();
232 if (ret)
233 goto out_racache;
234 return 0;
235
236out_racache:
237 nfsd_racache_shutdown();
238dec_users:
239 nfsd_users--;
240 return ret;
241}
242
243static void nfsd_shutdown_generic(void)
244{
245 if (--nfsd_users)
246 return;
247
248 nfs4_state_shutdown();
249 nfsd_racache_shutdown();
250}
251
252static bool nfsd_needs_lockd(void)
253{
254#if defined(CONFIG_NFSD_V3)
255 return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
256#else
257 return (nfsd_versions[2] != NULL);
258#endif
259}
260
261static int nfsd_startup_net(int nrservs, struct net *net)
262{
263 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
264 int ret;
265
266 if (nn->nfsd_net_up)
267 return 0;
268
269 ret = nfsd_startup_generic(nrservs);
270 if (ret)
271 return ret;
272 ret = nfsd_init_socks(net);
273 if (ret)
274 goto out_socks;
275
276 if (nfsd_needs_lockd() && !nn->lockd_up) {
277 ret = lockd_up(net);
278 if (ret)
279 goto out_socks;
280 nn->lockd_up = 1;
281 }
282
283 ret = nfs4_state_start_net(net);
284 if (ret)
285 goto out_lockd;
286
287 nn->nfsd_net_up = true;
288 return 0;
289
290out_lockd:
291 if (nn->lockd_up) {
292 lockd_down(net);
293 nn->lockd_up = 0;
294 }
295out_socks:
296 nfsd_shutdown_generic();
297 return ret;
298}
299
300static void nfsd_shutdown_net(struct net *net)
301{
302 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
303
304 nfs4_state_shutdown_net(net);
305 if (nn->lockd_up) {
306 lockd_down(net);
307 nn->lockd_up = 0;
308 }
309 nn->nfsd_net_up = false;
310 nfsd_shutdown_generic();
311}
312
313static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
314 void *ptr)
315{
316 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
317 struct net_device *dev = ifa->ifa_dev->dev;
318 struct net *net = dev_net(dev);
319 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
320 struct sockaddr_in sin;
321
322 if (event != NETDEV_DOWN)
323 goto out;
324
325 if (nn->nfsd_serv) {
326 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
327 sin.sin_family = AF_INET;
328 sin.sin_addr.s_addr = ifa->ifa_local;
329 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
330 }
331
332out:
333 return NOTIFY_DONE;
334}
335
336static struct notifier_block nfsd_inetaddr_notifier = {
337 .notifier_call = nfsd_inetaddr_event,
338};
339
340#if IS_ENABLED(CONFIG_IPV6)
341static int nfsd_inet6addr_event(struct notifier_block *this,
342 unsigned long event, void *ptr)
343{
344 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
345 struct net_device *dev = ifa->idev->dev;
346 struct net *net = dev_net(dev);
347 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
348 struct sockaddr_in6 sin6;
349
350 if (event != NETDEV_DOWN)
351 goto out;
352
353 if (nn->nfsd_serv) {
354 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
355 sin6.sin6_family = AF_INET6;
356 sin6.sin6_addr = ifa->addr;
357 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
358 }
359
360out:
361 return NOTIFY_DONE;
362}
363
364static struct notifier_block nfsd_inet6addr_notifier = {
365 .notifier_call = nfsd_inet6addr_event,
366};
367#endif
368
369/* Only used under nfsd_mutex, so this atomic may be overkill: */
370static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
371
372static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
373{
374 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
375
376 /* check if the notifier still has clients */
377 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
378 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
379#if IS_ENABLED(CONFIG_IPV6)
380 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
381#endif
382 }
383
384 /*
385 * write_ports can create the server without actually starting
386 * any threads--if we get shut down before any threads are
387 * started, then nfsd_last_thread will be run before any of this
388 * other initialization has been done except the rpcb information.
389 */
390 svc_rpcb_cleanup(serv, net);
391 if (!nn->nfsd_net_up)
392 return;
393
394 nfsd_shutdown_net(net);
395 printk(KERN_WARNING "nfsd: last server has exited, flushing export "
396 "cache\n");
397 nfsd_export_flush(net);
398}
399
400void nfsd_reset_versions(void)
401{
402 int found_one = 0;
403 int i;
404
405 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
406 if (nfsd_program.pg_vers[i])
407 found_one = 1;
408 }
409
410 if (!found_one) {
411 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
412 nfsd_program.pg_vers[i] = nfsd_version[i];
413#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
414 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
415 nfsd_acl_program.pg_vers[i] =
416 nfsd_acl_version[i];
417#endif
418 }
419}
420
421/*
422 * Each session guarantees a negotiated per slot memory cache for replies
423 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
424 * NFSv4.1 server might want to use more memory for a DRC than a machine
425 * with mutiple services.
426 *
427 * Impose a hard limit on the number of pages for the DRC which varies
428 * according to the machines free pages. This is of course only a default.
429 *
430 * For now this is a #defined shift which could be under admin control
431 * in the future.
432 */
433static void set_max_drc(void)
434{
435 #define NFSD_DRC_SIZE_SHIFT 10
436 nfsd_drc_max_mem = (nr_free_buffer_pages()
437 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
438 nfsd_drc_mem_used = 0;
439 spin_lock_init(&nfsd_drc_lock);
440 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
441}
442
443static int nfsd_get_default_max_blksize(void)
444{
445 struct sysinfo i;
446 unsigned long long target;
447 unsigned long ret;
448
449 si_meminfo(&i);
450 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
451 /*
452 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
453 * machines, but only uses 32K on 128M machines. Bottom out at
454 * 8K on 32M and smaller. Of course, this is only a default.
455 */
456 target >>= 12;
457
458 ret = NFSSVC_MAXBLKSIZE;
459 while (ret > target && ret >= 8*1024*2)
460 ret /= 2;
461 return ret;
462}
463
464static struct svc_serv_ops nfsd_thread_sv_ops = {
465 .svo_shutdown = nfsd_last_thread,
466 .svo_function = nfsd,
467 .svo_enqueue_xprt = svc_xprt_do_enqueue,
468 .svo_setup = svc_set_num_threads,
469 .svo_module = THIS_MODULE,
470};
471
472int nfsd_create_serv(struct net *net)
473{
474 int error;
475 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
476
477 WARN_ON(!mutex_is_locked(&nfsd_mutex));
478 if (nn->nfsd_serv) {
479 svc_get(nn->nfsd_serv);
480 return 0;
481 }
482 if (nfsd_max_blksize == 0)
483 nfsd_max_blksize = nfsd_get_default_max_blksize();
484 nfsd_reset_versions();
485 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
486 &nfsd_thread_sv_ops);
487 if (nn->nfsd_serv == NULL)
488 return -ENOMEM;
489
490 nn->nfsd_serv->sv_maxconn = nn->max_connections;
491 error = svc_bind(nn->nfsd_serv, net);
492 if (error < 0) {
493 svc_destroy(nn->nfsd_serv);
494 return error;
495 }
496
497 set_max_drc();
498 /* check if the notifier is already set */
499 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
500 register_inetaddr_notifier(&nfsd_inetaddr_notifier);
501#if IS_ENABLED(CONFIG_IPV6)
502 register_inet6addr_notifier(&nfsd_inet6addr_notifier);
503#endif
504 }
505 do_gettimeofday(&nn->nfssvc_boot); /* record boot time */
506 return 0;
507}
508
509int nfsd_nrpools(struct net *net)
510{
511 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
512
513 if (nn->nfsd_serv == NULL)
514 return 0;
515 else
516 return nn->nfsd_serv->sv_nrpools;
517}
518
519int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
520{
521 int i = 0;
522 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
523
524 if (nn->nfsd_serv != NULL) {
525 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
526 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
527 }
528
529 return 0;
530}
531
532void nfsd_destroy(struct net *net)
533{
534 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
535 int destroy = (nn->nfsd_serv->sv_nrthreads == 1);
536
537 if (destroy)
538 svc_shutdown_net(nn->nfsd_serv, net);
539 svc_destroy(nn->nfsd_serv);
540 if (destroy)
541 nn->nfsd_serv = NULL;
542}
543
544int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
545{
546 int i = 0;
547 int tot = 0;
548 int err = 0;
549 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
550
551 WARN_ON(!mutex_is_locked(&nfsd_mutex));
552
553 if (nn->nfsd_serv == NULL || n <= 0)
554 return 0;
555
556 if (n > nn->nfsd_serv->sv_nrpools)
557 n = nn->nfsd_serv->sv_nrpools;
558
559 /* enforce a global maximum number of threads */
560 tot = 0;
561 for (i = 0; i < n; i++) {
562 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
563 tot += nthreads[i];
564 }
565 if (tot > NFSD_MAXSERVS) {
566 /* total too large: scale down requested numbers */
567 for (i = 0; i < n && tot > 0; i++) {
568 int new = nthreads[i] * NFSD_MAXSERVS / tot;
569 tot -= (nthreads[i] - new);
570 nthreads[i] = new;
571 }
572 for (i = 0; i < n && tot > 0; i++) {
573 nthreads[i]--;
574 tot--;
575 }
576 }
577
578 /*
579 * There must always be a thread in pool 0; the admin
580 * can't shut down NFS completely using pool_threads.
581 */
582 if (nthreads[0] == 0)
583 nthreads[0] = 1;
584
585 /* apply the new numbers */
586 svc_get(nn->nfsd_serv);
587 for (i = 0; i < n; i++) {
588 err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
589 &nn->nfsd_serv->sv_pools[i], nthreads[i]);
590 if (err)
591 break;
592 }
593 nfsd_destroy(net);
594 return err;
595}
596
597/*
598 * Adjust the number of threads and return the new number of threads.
599 * This is also the function that starts the server if necessary, if
600 * this is the first time nrservs is nonzero.
601 */
602int
603nfsd_svc(int nrservs, struct net *net)
604{
605 int error;
606 bool nfsd_up_before;
607 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
608
609 mutex_lock(&nfsd_mutex);
610 dprintk("nfsd: creating service\n");
611
612 nrservs = max(nrservs, 0);
613 nrservs = min(nrservs, NFSD_MAXSERVS);
614 error = 0;
615
616 if (nrservs == 0 && nn->nfsd_serv == NULL)
617 goto out;
618
619 error = nfsd_create_serv(net);
620 if (error)
621 goto out;
622
623 nfsd_up_before = nn->nfsd_net_up;
624
625 error = nfsd_startup_net(nrservs, net);
626 if (error)
627 goto out_destroy;
628 error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
629 NULL, nrservs);
630 if (error)
631 goto out_shutdown;
632 /* We are holding a reference to nn->nfsd_serv which
633 * we don't want to count in the return value,
634 * so subtract 1
635 */
636 error = nn->nfsd_serv->sv_nrthreads - 1;
637out_shutdown:
638 if (error < 0 && !nfsd_up_before)
639 nfsd_shutdown_net(net);
640out_destroy:
641 nfsd_destroy(net); /* Release server */
642out:
643 mutex_unlock(&nfsd_mutex);
644 return error;
645}
646
647
648/*
649 * This is the NFS server kernel thread
650 */
651static int
652nfsd(void *vrqstp)
653{
654 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
655 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
656 struct net *net = perm_sock->xpt_net;
657 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
658 int err;
659
660 /* Lock module and set up kernel thread */
661 mutex_lock(&nfsd_mutex);
662
663 /* At this point, the thread shares current->fs
664 * with the init process. We need to create files with the
665 * umask as defined by the client instead of init's umask. */
666 if (unshare_fs_struct() < 0) {
667 printk("Unable to start nfsd thread: out of memory\n");
668 goto out;
669 }
670
671 current->fs->umask = 0;
672
673 /*
674 * thread is spawned with all signals set to SIG_IGN, re-enable
675 * the ones that will bring down the thread
676 */
677 allow_signal(SIGKILL);
678 allow_signal(SIGHUP);
679 allow_signal(SIGINT);
680 allow_signal(SIGQUIT);
681
682 nfsdstats.th_cnt++;
683 mutex_unlock(&nfsd_mutex);
684
685 set_freezable();
686
687 /*
688 * The main request loop
689 */
690 for (;;) {
691 /* Update sv_maxconn if it has changed */
692 rqstp->rq_server->sv_maxconn = nn->max_connections;
693
694 /*
695 * Find a socket with data available and call its
696 * recvfrom routine.
697 */
698 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
699 ;
700 if (err == -EINTR)
701 break;
702 validate_process_creds();
703 svc_process(rqstp);
704 validate_process_creds();
705 }
706
707 /* Clear signals before calling svc_exit_thread() */
708 flush_signals(current);
709
710 mutex_lock(&nfsd_mutex);
711 nfsdstats.th_cnt --;
712
713out:
714 rqstp->rq_server = NULL;
715
716 /* Release the thread */
717 svc_exit_thread(rqstp);
718
719 nfsd_destroy(net);
720
721 /* Release module */
722 mutex_unlock(&nfsd_mutex);
723 module_put_and_exit(0);
724 return 0;
725}
726
727static __be32 map_new_errors(u32 vers, __be32 nfserr)
728{
729 if (nfserr == nfserr_jukebox && vers == 2)
730 return nfserr_dropit;
731 if (nfserr == nfserr_wrongsec && vers < 4)
732 return nfserr_acces;
733 return nfserr;
734}
735
736int
737nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
738{
739 struct svc_procedure *proc;
740 kxdrproc_t xdr;
741 __be32 nfserr;
742 __be32 *nfserrp;
743
744 dprintk("nfsd_dispatch: vers %d proc %d\n",
745 rqstp->rq_vers, rqstp->rq_proc);
746 proc = rqstp->rq_procinfo;
747
748 /*
749 * Give the xdr decoder a chance to change this if it wants
750 * (necessary in the NFSv4.0 compound case)
751 */
752 rqstp->rq_cachetype = proc->pc_cachetype;
753 /* Decode arguments */
754 xdr = proc->pc_decode;
755 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
756 rqstp->rq_argp)) {
757 dprintk("nfsd: failed to decode arguments!\n");
758 *statp = rpc_garbage_args;
759 return 1;
760 }
761
762 /* Check whether we have this call in the cache. */
763 switch (nfsd_cache_lookup(rqstp)) {
764 case RC_DROPIT:
765 return 0;
766 case RC_REPLY:
767 return 1;
768 case RC_DOIT:;
769 /* do it */
770 }
771
772 /* need to grab the location to store the status, as
773 * nfsv4 does some encoding while processing
774 */
775 nfserrp = rqstp->rq_res.head[0].iov_base
776 + rqstp->rq_res.head[0].iov_len;
777 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
778
779 /* Now call the procedure handler, and encode NFS status. */
780 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
781 nfserr = map_new_errors(rqstp->rq_vers, nfserr);
782 if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) {
783 dprintk("nfsd: Dropping request; may be revisited later\n");
784 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
785 return 0;
786 }
787
788 if (rqstp->rq_proc != 0)
789 *nfserrp++ = nfserr;
790
791 /* Encode result.
792 * For NFSv2, additional info is never returned in case of an error.
793 */
794 if (!(nfserr && rqstp->rq_vers == 2)) {
795 xdr = proc->pc_encode;
796 if (xdr && !xdr(rqstp, nfserrp,
797 rqstp->rq_resp)) {
798 /* Failed to encode result. Release cache entry */
799 dprintk("nfsd: failed to encode result!\n");
800 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
801 *statp = rpc_system_err;
802 return 1;
803 }
804 }
805
806 /* Store reply in cache. */
807 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
808 return 1;
809}
810
811int nfsd_pool_stats_open(struct inode *inode, struct file *file)
812{
813 int ret;
814 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
815
816 mutex_lock(&nfsd_mutex);
817 if (nn->nfsd_serv == NULL) {
818 mutex_unlock(&nfsd_mutex);
819 return -ENODEV;
820 }
821 /* bump up the psudo refcount while traversing */
822 svc_get(nn->nfsd_serv);
823 ret = svc_pool_stats_open(nn->nfsd_serv, file);
824 mutex_unlock(&nfsd_mutex);
825 return ret;
826}
827
828int nfsd_pool_stats_release(struct inode *inode, struct file *file)
829{
830 int ret = seq_release(inode, file);
831 struct net *net = inode->i_sb->s_fs_info;
832
833 mutex_lock(&nfsd_mutex);
834 /* this function really, really should have been called svc_put() */
835 nfsd_destroy(net);
836 mutex_unlock(&nfsd_mutex);
837 return ret;
838}