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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/fs_struct.h>
12#include <linux/swap.h>
13
14#include <linux/sunrpc/stats.h>
15#include <linux/sunrpc/svcsock.h>
16#include <linux/lockd/bind.h>
17#include <linux/nfsacl.h>
18#include <linux/seq_file.h>
19#include <net/net_namespace.h>
20#include "nfsd.h"
21#include "cache.h"
22#include "vfs.h"
23
24#define NFSDDBG_FACILITY NFSDDBG_SVC
25
26extern struct svc_program nfsd_program;
27static int nfsd(void *vrqstp);
28struct timeval nfssvc_boot;
29
30/*
31 * nfsd_mutex protects nfsd_serv -- both the pointer itself and the members
32 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
33 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
34 *
35 * If (out side the lock) nfsd_serv is non-NULL, then it must point to a
36 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
37 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
38 * entry of ->sv_pools[].
39 *
40 * Transitions of the thread count between zero and non-zero are of particular
41 * interest since the svc_serv needs to be created and initialized at that
42 * point, or freed.
43 *
44 * Finally, the nfsd_mutex also protects some of the global variables that are
45 * accessed when nfsd starts and that are settable via the write_* routines in
46 * nfsctl.c. In particular:
47 *
48 * user_recovery_dirname
49 * user_lease_time
50 * nfsd_versions
51 */
52DEFINE_MUTEX(nfsd_mutex);
53struct svc_serv *nfsd_serv;
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 int nfsd_drc_max_mem;
63unsigned int 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
119u32 nfsd_supported_minorversion;
120
121int nfsd_vers(int vers, enum vers_op change)
122{
123 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
124 return 0;
125 switch(change) {
126 case NFSD_SET:
127 nfsd_versions[vers] = nfsd_version[vers];
128#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
129 if (vers < NFSD_ACL_NRVERS)
130 nfsd_acl_versions[vers] = nfsd_acl_version[vers];
131#endif
132 break;
133 case NFSD_CLEAR:
134 nfsd_versions[vers] = NULL;
135#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
136 if (vers < NFSD_ACL_NRVERS)
137 nfsd_acl_versions[vers] = NULL;
138#endif
139 break;
140 case NFSD_TEST:
141 return nfsd_versions[vers] != NULL;
142 case NFSD_AVAIL:
143 return nfsd_version[vers] != NULL;
144 }
145 return 0;
146}
147
148int nfsd_minorversion(u32 minorversion, enum vers_op change)
149{
150 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION)
151 return -1;
152 switch(change) {
153 case NFSD_SET:
154 nfsd_supported_minorversion = minorversion;
155 break;
156 case NFSD_CLEAR:
157 if (minorversion == 0)
158 return -1;
159 nfsd_supported_minorversion = minorversion - 1;
160 break;
161 case NFSD_TEST:
162 return minorversion <= nfsd_supported_minorversion;
163 case NFSD_AVAIL:
164 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
165 }
166 return 0;
167}
168
169/*
170 * Maximum number of nfsd processes
171 */
172#define NFSD_MAXSERVS 8192
173
174int nfsd_nrthreads(void)
175{
176 int rv = 0;
177 mutex_lock(&nfsd_mutex);
178 if (nfsd_serv)
179 rv = nfsd_serv->sv_nrthreads;
180 mutex_unlock(&nfsd_mutex);
181 return rv;
182}
183
184static int nfsd_init_socks(int port)
185{
186 int error;
187 if (!list_empty(&nfsd_serv->sv_permsocks))
188 return 0;
189
190 error = svc_create_xprt(nfsd_serv, "udp", &init_net, PF_INET, port,
191 SVC_SOCK_DEFAULTS);
192 if (error < 0)
193 return error;
194
195 error = svc_create_xprt(nfsd_serv, "tcp", &init_net, PF_INET, port,
196 SVC_SOCK_DEFAULTS);
197 if (error < 0)
198 return error;
199
200 return 0;
201}
202
203static bool nfsd_up = false;
204
205static int nfsd_startup(unsigned short port, int nrservs)
206{
207 int ret;
208
209 if (nfsd_up)
210 return 0;
211 /*
212 * Readahead param cache - will no-op if it already exists.
213 * (Note therefore results will be suboptimal if number of
214 * threads is modified after nfsd start.)
215 */
216 ret = nfsd_racache_init(2*nrservs);
217 if (ret)
218 return ret;
219 ret = nfsd_init_socks(port);
220 if (ret)
221 goto out_racache;
222 ret = lockd_up();
223 if (ret)
224 goto out_racache;
225 ret = nfs4_state_start();
226 if (ret)
227 goto out_lockd;
228 nfsd_up = true;
229 return 0;
230out_lockd:
231 lockd_down();
232out_racache:
233 nfsd_racache_shutdown();
234 return ret;
235}
236
237static void nfsd_shutdown(void)
238{
239 /*
240 * write_ports can create the server without actually starting
241 * any threads--if we get shut down before any threads are
242 * started, then nfsd_last_thread will be run before any of this
243 * other initialization has been done.
244 */
245 if (!nfsd_up)
246 return;
247 nfs4_state_shutdown();
248 lockd_down();
249 nfsd_racache_shutdown();
250 nfsd_up = false;
251}
252
253static void nfsd_last_thread(struct svc_serv *serv)
254{
255 /* When last nfsd thread exits we need to do some clean-up */
256 nfsd_serv = NULL;
257 nfsd_shutdown();
258
259 printk(KERN_WARNING "nfsd: last server has exited, flushing export "
260 "cache\n");
261 nfsd_export_flush();
262}
263
264void nfsd_reset_versions(void)
265{
266 int found_one = 0;
267 int i;
268
269 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
270 if (nfsd_program.pg_vers[i])
271 found_one = 1;
272 }
273
274 if (!found_one) {
275 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++)
276 nfsd_program.pg_vers[i] = nfsd_version[i];
277#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
278 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++)
279 nfsd_acl_program.pg_vers[i] =
280 nfsd_acl_version[i];
281#endif
282 }
283}
284
285/*
286 * Each session guarantees a negotiated per slot memory cache for replies
287 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
288 * NFSv4.1 server might want to use more memory for a DRC than a machine
289 * with mutiple services.
290 *
291 * Impose a hard limit on the number of pages for the DRC which varies
292 * according to the machines free pages. This is of course only a default.
293 *
294 * For now this is a #defined shift which could be under admin control
295 * in the future.
296 */
297static void set_max_drc(void)
298{
299 #define NFSD_DRC_SIZE_SHIFT 10
300 nfsd_drc_max_mem = (nr_free_buffer_pages()
301 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
302 nfsd_drc_mem_used = 0;
303 spin_lock_init(&nfsd_drc_lock);
304 dprintk("%s nfsd_drc_max_mem %u \n", __func__, nfsd_drc_max_mem);
305}
306
307int nfsd_create_serv(void)
308{
309 int err = 0;
310
311 WARN_ON(!mutex_is_locked(&nfsd_mutex));
312 if (nfsd_serv) {
313 svc_get(nfsd_serv);
314 return 0;
315 }
316 if (nfsd_max_blksize == 0) {
317 /* choose a suitable default */
318 struct sysinfo i;
319 si_meminfo(&i);
320 /* Aim for 1/4096 of memory per thread
321 * This gives 1MB on 4Gig machines
322 * But only uses 32K on 128M machines.
323 * Bottom out at 8K on 32M and smaller.
324 * Of course, this is only a default.
325 */
326 nfsd_max_blksize = NFSSVC_MAXBLKSIZE;
327 i.totalram <<= PAGE_SHIFT - 12;
328 while (nfsd_max_blksize > i.totalram &&
329 nfsd_max_blksize >= 8*1024*2)
330 nfsd_max_blksize /= 2;
331 }
332 nfsd_reset_versions();
333
334 nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
335 nfsd_last_thread, nfsd, THIS_MODULE);
336 if (nfsd_serv == NULL)
337 return -ENOMEM;
338
339 set_max_drc();
340 do_gettimeofday(&nfssvc_boot); /* record boot time */
341 return err;
342}
343
344int nfsd_nrpools(void)
345{
346 if (nfsd_serv == NULL)
347 return 0;
348 else
349 return nfsd_serv->sv_nrpools;
350}
351
352int nfsd_get_nrthreads(int n, int *nthreads)
353{
354 int i = 0;
355
356 if (nfsd_serv != NULL) {
357 for (i = 0; i < nfsd_serv->sv_nrpools && i < n; i++)
358 nthreads[i] = nfsd_serv->sv_pools[i].sp_nrthreads;
359 }
360
361 return 0;
362}
363
364int nfsd_set_nrthreads(int n, int *nthreads)
365{
366 int i = 0;
367 int tot = 0;
368 int err = 0;
369
370 WARN_ON(!mutex_is_locked(&nfsd_mutex));
371
372 if (nfsd_serv == NULL || n <= 0)
373 return 0;
374
375 if (n > nfsd_serv->sv_nrpools)
376 n = nfsd_serv->sv_nrpools;
377
378 /* enforce a global maximum number of threads */
379 tot = 0;
380 for (i = 0; i < n; i++) {
381 if (nthreads[i] > NFSD_MAXSERVS)
382 nthreads[i] = NFSD_MAXSERVS;
383 tot += nthreads[i];
384 }
385 if (tot > NFSD_MAXSERVS) {
386 /* total too large: scale down requested numbers */
387 for (i = 0; i < n && tot > 0; i++) {
388 int new = nthreads[i] * NFSD_MAXSERVS / tot;
389 tot -= (nthreads[i] - new);
390 nthreads[i] = new;
391 }
392 for (i = 0; i < n && tot > 0; i++) {
393 nthreads[i]--;
394 tot--;
395 }
396 }
397
398 /*
399 * There must always be a thread in pool 0; the admin
400 * can't shut down NFS completely using pool_threads.
401 */
402 if (nthreads[0] == 0)
403 nthreads[0] = 1;
404
405 /* apply the new numbers */
406 svc_get(nfsd_serv);
407 for (i = 0; i < n; i++) {
408 err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i],
409 nthreads[i]);
410 if (err)
411 break;
412 }
413 svc_destroy(nfsd_serv);
414
415 return err;
416}
417
418/*
419 * Adjust the number of threads and return the new number of threads.
420 * This is also the function that starts the server if necessary, if
421 * this is the first time nrservs is nonzero.
422 */
423int
424nfsd_svc(unsigned short port, int nrservs)
425{
426 int error;
427 bool nfsd_up_before;
428
429 mutex_lock(&nfsd_mutex);
430 dprintk("nfsd: creating service\n");
431 if (nrservs <= 0)
432 nrservs = 0;
433 if (nrservs > NFSD_MAXSERVS)
434 nrservs = NFSD_MAXSERVS;
435 error = 0;
436 if (nrservs == 0 && nfsd_serv == NULL)
437 goto out;
438
439 error = nfsd_create_serv();
440 if (error)
441 goto out;
442
443 nfsd_up_before = nfsd_up;
444
445 error = nfsd_startup(port, nrservs);
446 if (error)
447 goto out_destroy;
448 error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
449 if (error)
450 goto out_shutdown;
451 /* We are holding a reference to nfsd_serv which
452 * we don't want to count in the return value,
453 * so subtract 1
454 */
455 error = nfsd_serv->sv_nrthreads - 1;
456out_shutdown:
457 if (error < 0 && !nfsd_up_before)
458 nfsd_shutdown();
459out_destroy:
460 svc_destroy(nfsd_serv); /* Release server */
461out:
462 mutex_unlock(&nfsd_mutex);
463 return error;
464}
465
466
467/*
468 * This is the NFS server kernel thread
469 */
470static int
471nfsd(void *vrqstp)
472{
473 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
474 int err, preverr = 0;
475
476 /* Lock module and set up kernel thread */
477 mutex_lock(&nfsd_mutex);
478
479 /* At this point, the thread shares current->fs
480 * with the init process. We need to create files with a
481 * umask of 0 instead of init's umask. */
482 if (unshare_fs_struct() < 0) {
483 printk("Unable to start nfsd thread: out of memory\n");
484 goto out;
485 }
486
487 current->fs->umask = 0;
488
489 /*
490 * thread is spawned with all signals set to SIG_IGN, re-enable
491 * the ones that will bring down the thread
492 */
493 allow_signal(SIGKILL);
494 allow_signal(SIGHUP);
495 allow_signal(SIGINT);
496 allow_signal(SIGQUIT);
497
498 nfsdstats.th_cnt++;
499 mutex_unlock(&nfsd_mutex);
500
501 /*
502 * We want less throttling in balance_dirty_pages() so that nfs to
503 * localhost doesn't cause nfsd to lock up due to all the client's
504 * dirty pages.
505 */
506 current->flags |= PF_LESS_THROTTLE;
507 set_freezable();
508
509 /*
510 * The main request loop
511 */
512 for (;;) {
513 /*
514 * Find a socket with data available and call its
515 * recvfrom routine.
516 */
517 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
518 ;
519 if (err == -EINTR)
520 break;
521 else if (err < 0) {
522 if (err != preverr) {
523 printk(KERN_WARNING "%s: unexpected error "
524 "from svc_recv (%d)\n", __func__, -err);
525 preverr = err;
526 }
527 schedule_timeout_uninterruptible(HZ);
528 continue;
529 }
530
531 validate_process_creds();
532 svc_process(rqstp);
533 validate_process_creds();
534 }
535
536 /* Clear signals before calling svc_exit_thread() */
537 flush_signals(current);
538
539 mutex_lock(&nfsd_mutex);
540 nfsdstats.th_cnt --;
541
542out:
543 /* Release the thread */
544 svc_exit_thread(rqstp);
545
546 /* Release module */
547 mutex_unlock(&nfsd_mutex);
548 module_put_and_exit(0);
549 return 0;
550}
551
552static __be32 map_new_errors(u32 vers, __be32 nfserr)
553{
554 if (nfserr == nfserr_jukebox && vers == 2)
555 return nfserr_dropit;
556 if (nfserr == nfserr_wrongsec && vers < 4)
557 return nfserr_acces;
558 return nfserr;
559}
560
561int
562nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
563{
564 struct svc_procedure *proc;
565 kxdrproc_t xdr;
566 __be32 nfserr;
567 __be32 *nfserrp;
568
569 dprintk("nfsd_dispatch: vers %d proc %d\n",
570 rqstp->rq_vers, rqstp->rq_proc);
571 proc = rqstp->rq_procinfo;
572
573 /*
574 * Give the xdr decoder a chance to change this if it wants
575 * (necessary in the NFSv4.0 compound case)
576 */
577 rqstp->rq_cachetype = proc->pc_cachetype;
578 /* Decode arguments */
579 xdr = proc->pc_decode;
580 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base,
581 rqstp->rq_argp)) {
582 dprintk("nfsd: failed to decode arguments!\n");
583 *statp = rpc_garbage_args;
584 return 1;
585 }
586
587 /* Check whether we have this call in the cache. */
588 switch (nfsd_cache_lookup(rqstp)) {
589 case RC_INTR:
590 case RC_DROPIT:
591 return 0;
592 case RC_REPLY:
593 return 1;
594 case RC_DOIT:;
595 /* do it */
596 }
597
598 /* need to grab the location to store the status, as
599 * nfsv4 does some encoding while processing
600 */
601 nfserrp = rqstp->rq_res.head[0].iov_base
602 + rqstp->rq_res.head[0].iov_len;
603 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
604
605 /* Now call the procedure handler, and encode NFS status. */
606 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
607 nfserr = map_new_errors(rqstp->rq_vers, nfserr);
608 if (nfserr == nfserr_dropit || rqstp->rq_dropme) {
609 dprintk("nfsd: Dropping request; may be revisited later\n");
610 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
611 return 0;
612 }
613
614 if (rqstp->rq_proc != 0)
615 *nfserrp++ = nfserr;
616
617 /* Encode result.
618 * For NFSv2, additional info is never returned in case of an error.
619 */
620 if (!(nfserr && rqstp->rq_vers == 2)) {
621 xdr = proc->pc_encode;
622 if (xdr && !xdr(rqstp, nfserrp,
623 rqstp->rq_resp)) {
624 /* Failed to encode result. Release cache entry */
625 dprintk("nfsd: failed to encode result!\n");
626 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
627 *statp = rpc_system_err;
628 return 1;
629 }
630 }
631
632 /* Store reply in cache. */
633 nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1);
634 return 1;
635}
636
637int nfsd_pool_stats_open(struct inode *inode, struct file *file)
638{
639 int ret;
640 mutex_lock(&nfsd_mutex);
641 if (nfsd_serv == NULL) {
642 mutex_unlock(&nfsd_mutex);
643 return -ENODEV;
644 }
645 /* bump up the psudo refcount while traversing */
646 svc_get(nfsd_serv);
647 ret = svc_pool_stats_open(nfsd_serv, file);
648 mutex_unlock(&nfsd_mutex);
649 return ret;
650}
651
652int nfsd_pool_stats_release(struct inode *inode, struct file *file)
653{
654 int ret = seq_release(inode, file);
655 mutex_lock(&nfsd_mutex);
656 /* this function really, really should have been called svc_put() */
657 svc_destroy(nfsd_serv);
658 mutex_unlock(&nfsd_mutex);
659 return ret;
660}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Central processing for nfsd.
4 *
5 * Authors: Olaf Kirch (okir@monad.swb.de)
6 *
7 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
8 */
9
10#include <linux/sched/signal.h>
11#include <linux/freezer.h>
12#include <linux/module.h>
13#include <linux/fs_struct.h>
14#include <linux/swap.h>
15
16#include <linux/sunrpc/stats.h>
17#include <linux/sunrpc/svcsock.h>
18#include <linux/sunrpc/svc_xprt.h>
19#include <linux/lockd/bind.h>
20#include <linux/nfsacl.h>
21#include <linux/seq_file.h>
22#include <linux/inetdevice.h>
23#include <net/addrconf.h>
24#include <net/ipv6.h>
25#include <net/net_namespace.h>
26#include "nfsd.h"
27#include "cache.h"
28#include "vfs.h"
29#include "netns.h"
30
31#define NFSDDBG_FACILITY NFSDDBG_SVC
32
33extern struct svc_program nfsd_program;
34static int nfsd(void *vrqstp);
35
36/*
37 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
38 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some
39 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
40 *
41 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
42 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
43 * of nfsd threads must exist and each must listed in ->sp_all_threads in each
44 * entry of ->sv_pools[].
45 *
46 * Transitions of the thread count between zero and non-zero are of particular
47 * interest since the svc_serv needs to be created and initialized at that
48 * point, or freed.
49 *
50 * Finally, the nfsd_mutex also protects some of the global variables that are
51 * accessed when nfsd starts and that are settable via the write_* routines in
52 * nfsctl.c. In particular:
53 *
54 * user_recovery_dirname
55 * user_lease_time
56 * nfsd_versions
57 */
58DEFINE_MUTEX(nfsd_mutex);
59
60/*
61 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
62 * nfsd_drc_max_pages limits the total amount of memory available for
63 * version 4.1 DRC caches.
64 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
65 */
66spinlock_t nfsd_drc_lock;
67unsigned long nfsd_drc_max_mem;
68unsigned long nfsd_drc_mem_used;
69
70#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
71static struct svc_stat nfsd_acl_svcstats;
72static const struct svc_version *nfsd_acl_version[] = {
73 [2] = &nfsd_acl_version2,
74 [3] = &nfsd_acl_version3,
75};
76
77#define NFSD_ACL_MINVERS 2
78#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
79static const struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
80
81static struct svc_program nfsd_acl_program = {
82 .pg_prog = NFS_ACL_PROGRAM,
83 .pg_nvers = NFSD_ACL_NRVERS,
84 .pg_vers = nfsd_acl_versions,
85 .pg_name = "nfsacl",
86 .pg_class = "nfsd",
87 .pg_stats = &nfsd_acl_svcstats,
88 .pg_authenticate = &svc_set_client,
89};
90
91static struct svc_stat nfsd_acl_svcstats = {
92 .program = &nfsd_acl_program,
93};
94#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
95
96static const struct svc_version *nfsd_version[] = {
97 [2] = &nfsd_version2,
98#if defined(CONFIG_NFSD_V3)
99 [3] = &nfsd_version3,
100#endif
101#if defined(CONFIG_NFSD_V4)
102 [4] = &nfsd_version4,
103#endif
104};
105
106#define NFSD_MINVERS 2
107#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
108static const struct svc_version *nfsd_versions[NFSD_NRVERS];
109
110struct svc_program nfsd_program = {
111#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
112 .pg_next = &nfsd_acl_program,
113#endif
114 .pg_prog = NFS_PROGRAM, /* program number */
115 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
116 .pg_vers = nfsd_versions, /* version table */
117 .pg_name = "nfsd", /* program name */
118 .pg_class = "nfsd", /* authentication class */
119 .pg_stats = &nfsd_svcstats, /* version table */
120 .pg_authenticate = &svc_set_client, /* export authentication */
121
122};
123
124static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = {
125 [0] = 1,
126 [1] = 1,
127 [2] = 1,
128};
129
130int nfsd_vers(int vers, enum vers_op change)
131{
132 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
133 return 0;
134 switch(change) {
135 case NFSD_SET:
136 nfsd_versions[vers] = nfsd_version[vers];
137#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
138 if (vers < NFSD_ACL_NRVERS)
139 nfsd_acl_versions[vers] = nfsd_acl_version[vers];
140#endif
141 break;
142 case NFSD_CLEAR:
143 nfsd_versions[vers] = NULL;
144#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
145 if (vers < NFSD_ACL_NRVERS)
146 nfsd_acl_versions[vers] = NULL;
147#endif
148 break;
149 case NFSD_TEST:
150 return nfsd_versions[vers] != NULL;
151 case NFSD_AVAIL:
152 return nfsd_version[vers] != NULL;
153 }
154 return 0;
155}
156
157static void
158nfsd_adjust_nfsd_versions4(void)
159{
160 unsigned i;
161
162 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
163 if (nfsd_supported_minorversions[i])
164 return;
165 }
166 nfsd_vers(4, NFSD_CLEAR);
167}
168
169int nfsd_minorversion(u32 minorversion, enum vers_op change)
170{
171 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
172 change != NFSD_AVAIL)
173 return -1;
174 switch(change) {
175 case NFSD_SET:
176 nfsd_supported_minorversions[minorversion] = true;
177 nfsd_vers(4, NFSD_SET);
178 break;
179 case NFSD_CLEAR:
180 nfsd_supported_minorversions[minorversion] = false;
181 nfsd_adjust_nfsd_versions4();
182 break;
183 case NFSD_TEST:
184 return nfsd_supported_minorversions[minorversion];
185 case NFSD_AVAIL:
186 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
187 }
188 return 0;
189}
190
191/*
192 * Maximum number of nfsd processes
193 */
194#define NFSD_MAXSERVS 8192
195
196int nfsd_nrthreads(struct net *net)
197{
198 int rv = 0;
199 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
200
201 mutex_lock(&nfsd_mutex);
202 if (nn->nfsd_serv)
203 rv = nn->nfsd_serv->sv_nrthreads;
204 mutex_unlock(&nfsd_mutex);
205 return rv;
206}
207
208static int nfsd_init_socks(struct net *net)
209{
210 int error;
211 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
212
213 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
214 return 0;
215
216 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
217 SVC_SOCK_DEFAULTS);
218 if (error < 0)
219 return error;
220
221 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
222 SVC_SOCK_DEFAULTS);
223 if (error < 0)
224 return error;
225
226 return 0;
227}
228
229static int nfsd_users = 0;
230
231static int nfsd_startup_generic(int nrservs)
232{
233 int ret;
234
235 if (nfsd_users++)
236 return 0;
237
238 /*
239 * Readahead param cache - will no-op if it already exists.
240 * (Note therefore results will be suboptimal if number of
241 * threads is modified after nfsd start.)
242 */
243 ret = nfsd_racache_init(2*nrservs);
244 if (ret)
245 goto dec_users;
246
247 ret = nfs4_state_start();
248 if (ret)
249 goto out_racache;
250 return 0;
251
252out_racache:
253 nfsd_racache_shutdown();
254dec_users:
255 nfsd_users--;
256 return ret;
257}
258
259static void nfsd_shutdown_generic(void)
260{
261 if (--nfsd_users)
262 return;
263
264 nfs4_state_shutdown();
265 nfsd_racache_shutdown();
266}
267
268static bool nfsd_needs_lockd(void)
269{
270#if defined(CONFIG_NFSD_V3)
271 return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
272#else
273 return (nfsd_versions[2] != NULL);
274#endif
275}
276
277static int nfsd_startup_net(int nrservs, struct net *net)
278{
279 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
280 int ret;
281
282 if (nn->nfsd_net_up)
283 return 0;
284
285 ret = nfsd_startup_generic(nrservs);
286 if (ret)
287 return ret;
288 ret = nfsd_init_socks(net);
289 if (ret)
290 goto out_socks;
291
292 if (nfsd_needs_lockd() && !nn->lockd_up) {
293 ret = lockd_up(net);
294 if (ret)
295 goto out_socks;
296 nn->lockd_up = 1;
297 }
298
299 ret = nfs4_state_start_net(net);
300 if (ret)
301 goto out_lockd;
302
303 nn->nfsd_net_up = true;
304 return 0;
305
306out_lockd:
307 if (nn->lockd_up) {
308 lockd_down(net);
309 nn->lockd_up = 0;
310 }
311out_socks:
312 nfsd_shutdown_generic();
313 return ret;
314}
315
316static void nfsd_shutdown_net(struct net *net)
317{
318 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
319
320 nfs4_state_shutdown_net(net);
321 if (nn->lockd_up) {
322 lockd_down(net);
323 nn->lockd_up = 0;
324 }
325 nn->nfsd_net_up = false;
326 nfsd_shutdown_generic();
327}
328
329static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
330 void *ptr)
331{
332 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
333 struct net_device *dev = ifa->ifa_dev->dev;
334 struct net *net = dev_net(dev);
335 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
336 struct sockaddr_in sin;
337
338 if ((event != NETDEV_DOWN) ||
339 !atomic_inc_not_zero(&nn->ntf_refcnt))
340 goto out;
341
342 if (nn->nfsd_serv) {
343 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
344 sin.sin_family = AF_INET;
345 sin.sin_addr.s_addr = ifa->ifa_local;
346 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
347 }
348 atomic_dec(&nn->ntf_refcnt);
349 wake_up(&nn->ntf_wq);
350
351out:
352 return NOTIFY_DONE;
353}
354
355static struct notifier_block nfsd_inetaddr_notifier = {
356 .notifier_call = nfsd_inetaddr_event,
357};
358
359#if IS_ENABLED(CONFIG_IPV6)
360static int nfsd_inet6addr_event(struct notifier_block *this,
361 unsigned long event, void *ptr)
362{
363 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
364 struct net_device *dev = ifa->idev->dev;
365 struct net *net = dev_net(dev);
366 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
367 struct sockaddr_in6 sin6;
368
369 if ((event != NETDEV_DOWN) ||
370 !atomic_inc_not_zero(&nn->ntf_refcnt))
371 goto out;
372
373 if (nn->nfsd_serv) {
374 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
375 sin6.sin6_family = AF_INET6;
376 sin6.sin6_addr = ifa->addr;
377 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
378 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
379 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
380 }
381 atomic_dec(&nn->ntf_refcnt);
382 wake_up(&nn->ntf_wq);
383out:
384 return NOTIFY_DONE;
385}
386
387static struct notifier_block nfsd_inet6addr_notifier = {
388 .notifier_call = nfsd_inet6addr_event,
389};
390#endif
391
392/* Only used under nfsd_mutex, so this atomic may be overkill: */
393static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
394
395static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
396{
397 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
398
399 atomic_dec(&nn->ntf_refcnt);
400 /* check if the notifier still has clients */
401 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
402 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
403#if IS_ENABLED(CONFIG_IPV6)
404 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
405#endif
406 }
407 wait_event(nn->ntf_wq, atomic_read(&nn->ntf_refcnt) == 0);
408
409 /*
410 * write_ports can create the server without actually starting
411 * any threads--if we get shut down before any threads are
412 * started, then nfsd_last_thread will be run before any of this
413 * other initialization has been done except the rpcb information.
414 */
415 svc_rpcb_cleanup(serv, net);
416 if (!nn->nfsd_net_up)
417 return;
418
419 nfsd_shutdown_net(net);
420 printk(KERN_WARNING "nfsd: last server has exited, flushing export "
421 "cache\n");
422 nfsd_export_flush(net);
423}
424
425void nfsd_reset_versions(void)
426{
427 int i;
428
429 for (i = 0; i < NFSD_NRVERS; i++)
430 if (nfsd_vers(i, NFSD_TEST))
431 return;
432
433 for (i = 0; i < NFSD_NRVERS; i++)
434 if (i != 4)
435 nfsd_vers(i, NFSD_SET);
436 else {
437 int minor = 0;
438 while (nfsd_minorversion(minor, NFSD_SET) >= 0)
439 minor++;
440 }
441}
442
443/*
444 * Each session guarantees a negotiated per slot memory cache for replies
445 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
446 * NFSv4.1 server might want to use more memory for a DRC than a machine
447 * with mutiple services.
448 *
449 * Impose a hard limit on the number of pages for the DRC which varies
450 * according to the machines free pages. This is of course only a default.
451 *
452 * For now this is a #defined shift which could be under admin control
453 * in the future.
454 */
455static void set_max_drc(void)
456{
457 #define NFSD_DRC_SIZE_SHIFT 7
458 nfsd_drc_max_mem = (nr_free_buffer_pages()
459 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
460 nfsd_drc_mem_used = 0;
461 spin_lock_init(&nfsd_drc_lock);
462 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
463}
464
465static int nfsd_get_default_max_blksize(void)
466{
467 struct sysinfo i;
468 unsigned long long target;
469 unsigned long ret;
470
471 si_meminfo(&i);
472 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
473 /*
474 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
475 * machines, but only uses 32K on 128M machines. Bottom out at
476 * 8K on 32M and smaller. Of course, this is only a default.
477 */
478 target >>= 12;
479
480 ret = NFSSVC_MAXBLKSIZE;
481 while (ret > target && ret >= 8*1024*2)
482 ret /= 2;
483 return ret;
484}
485
486static const struct svc_serv_ops nfsd_thread_sv_ops = {
487 .svo_shutdown = nfsd_last_thread,
488 .svo_function = nfsd,
489 .svo_enqueue_xprt = svc_xprt_do_enqueue,
490 .svo_setup = svc_set_num_threads,
491 .svo_module = THIS_MODULE,
492};
493
494int nfsd_create_serv(struct net *net)
495{
496 int error;
497 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
498
499 WARN_ON(!mutex_is_locked(&nfsd_mutex));
500 if (nn->nfsd_serv) {
501 svc_get(nn->nfsd_serv);
502 return 0;
503 }
504 if (nfsd_max_blksize == 0)
505 nfsd_max_blksize = nfsd_get_default_max_blksize();
506 nfsd_reset_versions();
507 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
508 &nfsd_thread_sv_ops);
509 if (nn->nfsd_serv == NULL)
510 return -ENOMEM;
511
512 nn->nfsd_serv->sv_maxconn = nn->max_connections;
513 error = svc_bind(nn->nfsd_serv, net);
514 if (error < 0) {
515 svc_destroy(nn->nfsd_serv);
516 return error;
517 }
518
519 set_max_drc();
520 /* check if the notifier is already set */
521 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
522 register_inetaddr_notifier(&nfsd_inetaddr_notifier);
523#if IS_ENABLED(CONFIG_IPV6)
524 register_inet6addr_notifier(&nfsd_inet6addr_notifier);
525#endif
526 }
527 atomic_inc(&nn->ntf_refcnt);
528 ktime_get_real_ts64(&nn->nfssvc_boot); /* record boot time */
529 return 0;
530}
531
532int nfsd_nrpools(struct net *net)
533{
534 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
535
536 if (nn->nfsd_serv == NULL)
537 return 0;
538 else
539 return nn->nfsd_serv->sv_nrpools;
540}
541
542int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
543{
544 int i = 0;
545 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
546
547 if (nn->nfsd_serv != NULL) {
548 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
549 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
550 }
551
552 return 0;
553}
554
555void nfsd_destroy(struct net *net)
556{
557 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
558 int destroy = (nn->nfsd_serv->sv_nrthreads == 1);
559
560 if (destroy)
561 svc_shutdown_net(nn->nfsd_serv, net);
562 svc_destroy(nn->nfsd_serv);
563 if (destroy)
564 nn->nfsd_serv = NULL;
565}
566
567int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
568{
569 int i = 0;
570 int tot = 0;
571 int err = 0;
572 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
573
574 WARN_ON(!mutex_is_locked(&nfsd_mutex));
575
576 if (nn->nfsd_serv == NULL || n <= 0)
577 return 0;
578
579 if (n > nn->nfsd_serv->sv_nrpools)
580 n = nn->nfsd_serv->sv_nrpools;
581
582 /* enforce a global maximum number of threads */
583 tot = 0;
584 for (i = 0; i < n; i++) {
585 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
586 tot += nthreads[i];
587 }
588 if (tot > NFSD_MAXSERVS) {
589 /* total too large: scale down requested numbers */
590 for (i = 0; i < n && tot > 0; i++) {
591 int new = nthreads[i] * NFSD_MAXSERVS / tot;
592 tot -= (nthreads[i] - new);
593 nthreads[i] = new;
594 }
595 for (i = 0; i < n && tot > 0; i++) {
596 nthreads[i]--;
597 tot--;
598 }
599 }
600
601 /*
602 * There must always be a thread in pool 0; the admin
603 * can't shut down NFS completely using pool_threads.
604 */
605 if (nthreads[0] == 0)
606 nthreads[0] = 1;
607
608 /* apply the new numbers */
609 svc_get(nn->nfsd_serv);
610 for (i = 0; i < n; i++) {
611 err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
612 &nn->nfsd_serv->sv_pools[i], nthreads[i]);
613 if (err)
614 break;
615 }
616 nfsd_destroy(net);
617 return err;
618}
619
620/*
621 * Adjust the number of threads and return the new number of threads.
622 * This is also the function that starts the server if necessary, if
623 * this is the first time nrservs is nonzero.
624 */
625int
626nfsd_svc(int nrservs, struct net *net)
627{
628 int error;
629 bool nfsd_up_before;
630 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
631
632 mutex_lock(&nfsd_mutex);
633 dprintk("nfsd: creating service\n");
634
635 nrservs = max(nrservs, 0);
636 nrservs = min(nrservs, NFSD_MAXSERVS);
637 error = 0;
638
639 if (nrservs == 0 && nn->nfsd_serv == NULL)
640 goto out;
641
642 error = nfsd_create_serv(net);
643 if (error)
644 goto out;
645
646 nfsd_up_before = nn->nfsd_net_up;
647
648 error = nfsd_startup_net(nrservs, net);
649 if (error)
650 goto out_destroy;
651 error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
652 NULL, nrservs);
653 if (error)
654 goto out_shutdown;
655 /* We are holding a reference to nn->nfsd_serv which
656 * we don't want to count in the return value,
657 * so subtract 1
658 */
659 error = nn->nfsd_serv->sv_nrthreads - 1;
660out_shutdown:
661 if (error < 0 && !nfsd_up_before)
662 nfsd_shutdown_net(net);
663out_destroy:
664 nfsd_destroy(net); /* Release server */
665out:
666 mutex_unlock(&nfsd_mutex);
667 return error;
668}
669
670
671/*
672 * This is the NFS server kernel thread
673 */
674static int
675nfsd(void *vrqstp)
676{
677 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
678 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
679 struct net *net = perm_sock->xpt_net;
680 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
681 int err;
682
683 /* Lock module and set up kernel thread */
684 mutex_lock(&nfsd_mutex);
685
686 /* At this point, the thread shares current->fs
687 * with the init process. We need to create files with the
688 * umask as defined by the client instead of init's umask. */
689 if (unshare_fs_struct() < 0) {
690 printk("Unable to start nfsd thread: out of memory\n");
691 goto out;
692 }
693
694 current->fs->umask = 0;
695
696 /*
697 * thread is spawned with all signals set to SIG_IGN, re-enable
698 * the ones that will bring down the thread
699 */
700 allow_signal(SIGKILL);
701 allow_signal(SIGHUP);
702 allow_signal(SIGINT);
703 allow_signal(SIGQUIT);
704
705 nfsdstats.th_cnt++;
706 mutex_unlock(&nfsd_mutex);
707
708 set_freezable();
709
710 /*
711 * The main request loop
712 */
713 for (;;) {
714 /* Update sv_maxconn if it has changed */
715 rqstp->rq_server->sv_maxconn = nn->max_connections;
716
717 /*
718 * Find a socket with data available and call its
719 * recvfrom routine.
720 */
721 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
722 ;
723 if (err == -EINTR)
724 break;
725 validate_process_creds();
726 svc_process(rqstp);
727 validate_process_creds();
728 }
729
730 /* Clear signals before calling svc_exit_thread() */
731 flush_signals(current);
732
733 mutex_lock(&nfsd_mutex);
734 nfsdstats.th_cnt --;
735
736out:
737 rqstp->rq_server = NULL;
738
739 /* Release the thread */
740 svc_exit_thread(rqstp);
741
742 nfsd_destroy(net);
743
744 /* Release module */
745 mutex_unlock(&nfsd_mutex);
746 module_put_and_exit(0);
747 return 0;
748}
749
750static __be32 map_new_errors(u32 vers, __be32 nfserr)
751{
752 if (nfserr == nfserr_jukebox && vers == 2)
753 return nfserr_dropit;
754 if (nfserr == nfserr_wrongsec && vers < 4)
755 return nfserr_acces;
756 return nfserr;
757}
758
759/*
760 * A write procedure can have a large argument, and a read procedure can
761 * have a large reply, but no NFSv2 or NFSv3 procedure has argument and
762 * reply that can both be larger than a page. The xdr code has taken
763 * advantage of this assumption to be a sloppy about bounds checking in
764 * some cases. Pending a rewrite of the NFSv2/v3 xdr code to fix that
765 * problem, we enforce these assumptions here:
766 */
767static bool nfs_request_too_big(struct svc_rqst *rqstp,
768 const struct svc_procedure *proc)
769{
770 /*
771 * The ACL code has more careful bounds-checking and is not
772 * susceptible to this problem:
773 */
774 if (rqstp->rq_prog != NFS_PROGRAM)
775 return false;
776 /*
777 * Ditto NFSv4 (which can in theory have argument and reply both
778 * more than a page):
779 */
780 if (rqstp->rq_vers >= 4)
781 return false;
782 /* The reply will be small, we're OK: */
783 if (proc->pc_xdrressize > 0 &&
784 proc->pc_xdrressize < XDR_QUADLEN(PAGE_SIZE))
785 return false;
786
787 return rqstp->rq_arg.len > PAGE_SIZE;
788}
789
790int
791nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
792{
793 const struct svc_procedure *proc;
794 __be32 nfserr;
795 __be32 *nfserrp;
796
797 dprintk("nfsd_dispatch: vers %d proc %d\n",
798 rqstp->rq_vers, rqstp->rq_proc);
799 proc = rqstp->rq_procinfo;
800
801 if (nfs_request_too_big(rqstp, proc)) {
802 dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers);
803 *statp = rpc_garbage_args;
804 return 1;
805 }
806 /*
807 * Give the xdr decoder a chance to change this if it wants
808 * (necessary in the NFSv4.0 compound case)
809 */
810 rqstp->rq_cachetype = proc->pc_cachetype;
811 /* Decode arguments */
812 if (proc->pc_decode &&
813 !proc->pc_decode(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base)) {
814 dprintk("nfsd: failed to decode arguments!\n");
815 *statp = rpc_garbage_args;
816 return 1;
817 }
818
819 /* Check whether we have this call in the cache. */
820 switch (nfsd_cache_lookup(rqstp)) {
821 case RC_DROPIT:
822 return 0;
823 case RC_REPLY:
824 return 1;
825 case RC_DOIT:;
826 /* do it */
827 }
828
829 /* need to grab the location to store the status, as
830 * nfsv4 does some encoding while processing
831 */
832 nfserrp = rqstp->rq_res.head[0].iov_base
833 + rqstp->rq_res.head[0].iov_len;
834 rqstp->rq_res.head[0].iov_len += sizeof(__be32);
835
836 /* Now call the procedure handler, and encode NFS status. */
837 nfserr = proc->pc_func(rqstp);
838 nfserr = map_new_errors(rqstp->rq_vers, nfserr);
839 if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) {
840 dprintk("nfsd: Dropping request; may be revisited later\n");
841 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
842 return 0;
843 }
844
845 if (rqstp->rq_proc != 0)
846 *nfserrp++ = nfserr;
847
848 /* Encode result.
849 * For NFSv2, additional info is never returned in case of an error.
850 */
851 if (!(nfserr && rqstp->rq_vers == 2)) {
852 if (proc->pc_encode && !proc->pc_encode(rqstp, nfserrp)) {
853 /* Failed to encode result. Release cache entry */
854 dprintk("nfsd: failed to encode result!\n");
855 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
856 *statp = rpc_system_err;
857 return 1;
858 }
859 }
860
861 /* Store reply in cache. */
862 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
863 return 1;
864}
865
866int nfsd_pool_stats_open(struct inode *inode, struct file *file)
867{
868 int ret;
869 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
870
871 mutex_lock(&nfsd_mutex);
872 if (nn->nfsd_serv == NULL) {
873 mutex_unlock(&nfsd_mutex);
874 return -ENODEV;
875 }
876 /* bump up the psudo refcount while traversing */
877 svc_get(nn->nfsd_serv);
878 ret = svc_pool_stats_open(nn->nfsd_serv, file);
879 mutex_unlock(&nfsd_mutex);
880 return ret;
881}
882
883int nfsd_pool_stats_release(struct inode *inode, struct file *file)
884{
885 int ret = seq_release(inode, file);
886 struct net *net = inode->i_sb->s_fs_info;
887
888 mutex_lock(&nfsd_mutex);
889 /* this function really, really should have been called svc_put() */
890 nfsd_destroy(net);
891 mutex_unlock(&nfsd_mutex);
892 return ret;
893}