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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#include <linux/siphash.h>
16
17#include <linux/sunrpc/stats.h>
18#include <linux/sunrpc/svcsock.h>
19#include <linux/sunrpc/svc_xprt.h>
20#include <linux/lockd/bind.h>
21#include <linux/nfsacl.h>
22#include <linux/seq_file.h>
23#include <linux/inetdevice.h>
24#include <net/addrconf.h>
25#include <net/ipv6.h>
26#include <net/net_namespace.h>
27#include "nfsd.h"
28#include "cache.h"
29#include "vfs.h"
30#include "netns.h"
31#include "filecache.h"
32
33#include "trace.h"
34
35#define NFSDDBG_FACILITY NFSDDBG_SVC
36
37extern struct svc_program nfsd_program;
38static int nfsd(void *vrqstp);
39#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
40static int nfsd_acl_rpcbind_set(struct net *,
41 const struct svc_program *,
42 u32, int,
43 unsigned short,
44 unsigned short);
45static __be32 nfsd_acl_init_request(struct svc_rqst *,
46 const struct svc_program *,
47 struct svc_process_info *);
48#endif
49static int nfsd_rpcbind_set(struct net *,
50 const struct svc_program *,
51 u32, int,
52 unsigned short,
53 unsigned short);
54static __be32 nfsd_init_request(struct svc_rqst *,
55 const struct svc_program *,
56 struct svc_process_info *);
57
58/*
59 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and some members
60 * of the svc_serv struct such as ->sv_temp_socks and ->sv_permsocks.
61 *
62 * Finally, the nfsd_mutex also protects some of the global variables that are
63 * accessed when nfsd starts and that are settable via the write_* routines in
64 * nfsctl.c. In particular:
65 *
66 * user_recovery_dirname
67 * user_lease_time
68 * nfsd_versions
69 */
70DEFINE_MUTEX(nfsd_mutex);
71
72/*
73 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
74 * nfsd_drc_max_pages limits the total amount of memory available for
75 * version 4.1 DRC caches.
76 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
77 */
78DEFINE_SPINLOCK(nfsd_drc_lock);
79unsigned long nfsd_drc_max_mem;
80unsigned long nfsd_drc_mem_used;
81
82#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
83static struct svc_stat nfsd_acl_svcstats;
84static const struct svc_version *nfsd_acl_version[] = {
85# if defined(CONFIG_NFSD_V2_ACL)
86 [2] = &nfsd_acl_version2,
87# endif
88# if defined(CONFIG_NFSD_V3_ACL)
89 [3] = &nfsd_acl_version3,
90# endif
91};
92
93#define NFSD_ACL_MINVERS 2
94#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
95
96static struct svc_program nfsd_acl_program = {
97 .pg_prog = NFS_ACL_PROGRAM,
98 .pg_nvers = NFSD_ACL_NRVERS,
99 .pg_vers = nfsd_acl_version,
100 .pg_name = "nfsacl",
101 .pg_class = "nfsd",
102 .pg_stats = &nfsd_acl_svcstats,
103 .pg_authenticate = &svc_set_client,
104 .pg_init_request = nfsd_acl_init_request,
105 .pg_rpcbind_set = nfsd_acl_rpcbind_set,
106};
107
108static struct svc_stat nfsd_acl_svcstats = {
109 .program = &nfsd_acl_program,
110};
111#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
112
113static const struct svc_version *nfsd_version[] = {
114#if defined(CONFIG_NFSD_V2)
115 [2] = &nfsd_version2,
116#endif
117 [3] = &nfsd_version3,
118#if defined(CONFIG_NFSD_V4)
119 [4] = &nfsd_version4,
120#endif
121};
122
123#define NFSD_MINVERS 2
124#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
125
126struct svc_program nfsd_program = {
127#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
128 .pg_next = &nfsd_acl_program,
129#endif
130 .pg_prog = NFS_PROGRAM, /* program number */
131 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
132 .pg_vers = nfsd_version, /* version table */
133 .pg_name = "nfsd", /* program name */
134 .pg_class = "nfsd", /* authentication class */
135 .pg_stats = &nfsd_svcstats, /* version table */
136 .pg_authenticate = &svc_set_client, /* export authentication */
137 .pg_init_request = nfsd_init_request,
138 .pg_rpcbind_set = nfsd_rpcbind_set,
139};
140
141static bool
142nfsd_support_version(int vers)
143{
144 if (vers >= NFSD_MINVERS && vers < NFSD_NRVERS)
145 return nfsd_version[vers] != NULL;
146 return false;
147}
148
149static bool *
150nfsd_alloc_versions(void)
151{
152 bool *vers = kmalloc_array(NFSD_NRVERS, sizeof(bool), GFP_KERNEL);
153 unsigned i;
154
155 if (vers) {
156 /* All compiled versions are enabled by default */
157 for (i = 0; i < NFSD_NRVERS; i++)
158 vers[i] = nfsd_support_version(i);
159 }
160 return vers;
161}
162
163static bool *
164nfsd_alloc_minorversions(void)
165{
166 bool *vers = kmalloc_array(NFSD_SUPPORTED_MINOR_VERSION + 1,
167 sizeof(bool), GFP_KERNEL);
168 unsigned i;
169
170 if (vers) {
171 /* All minor versions are enabled by default */
172 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++)
173 vers[i] = nfsd_support_version(4);
174 }
175 return vers;
176}
177
178void
179nfsd_netns_free_versions(struct nfsd_net *nn)
180{
181 kfree(nn->nfsd_versions);
182 kfree(nn->nfsd4_minorversions);
183 nn->nfsd_versions = NULL;
184 nn->nfsd4_minorversions = NULL;
185}
186
187static void
188nfsd_netns_init_versions(struct nfsd_net *nn)
189{
190 if (!nn->nfsd_versions) {
191 nn->nfsd_versions = nfsd_alloc_versions();
192 nn->nfsd4_minorversions = nfsd_alloc_minorversions();
193 if (!nn->nfsd_versions || !nn->nfsd4_minorversions)
194 nfsd_netns_free_versions(nn);
195 }
196}
197
198int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change)
199{
200 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
201 return 0;
202 switch(change) {
203 case NFSD_SET:
204 if (nn->nfsd_versions)
205 nn->nfsd_versions[vers] = nfsd_support_version(vers);
206 break;
207 case NFSD_CLEAR:
208 nfsd_netns_init_versions(nn);
209 if (nn->nfsd_versions)
210 nn->nfsd_versions[vers] = false;
211 break;
212 case NFSD_TEST:
213 if (nn->nfsd_versions)
214 return nn->nfsd_versions[vers];
215 fallthrough;
216 case NFSD_AVAIL:
217 return nfsd_support_version(vers);
218 }
219 return 0;
220}
221
222static void
223nfsd_adjust_nfsd_versions4(struct nfsd_net *nn)
224{
225 unsigned i;
226
227 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
228 if (nn->nfsd4_minorversions[i])
229 return;
230 }
231 nfsd_vers(nn, 4, NFSD_CLEAR);
232}
233
234int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change)
235{
236 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
237 change != NFSD_AVAIL)
238 return -1;
239
240 switch(change) {
241 case NFSD_SET:
242 if (nn->nfsd4_minorversions) {
243 nfsd_vers(nn, 4, NFSD_SET);
244 nn->nfsd4_minorversions[minorversion] =
245 nfsd_vers(nn, 4, NFSD_TEST);
246 }
247 break;
248 case NFSD_CLEAR:
249 nfsd_netns_init_versions(nn);
250 if (nn->nfsd4_minorversions) {
251 nn->nfsd4_minorversions[minorversion] = false;
252 nfsd_adjust_nfsd_versions4(nn);
253 }
254 break;
255 case NFSD_TEST:
256 if (nn->nfsd4_minorversions)
257 return nn->nfsd4_minorversions[minorversion];
258 return nfsd_vers(nn, 4, NFSD_TEST);
259 case NFSD_AVAIL:
260 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION &&
261 nfsd_vers(nn, 4, NFSD_AVAIL);
262 }
263 return 0;
264}
265
266/*
267 * Maximum number of nfsd processes
268 */
269#define NFSD_MAXSERVS 8192
270
271int nfsd_nrthreads(struct net *net)
272{
273 int rv = 0;
274 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
275
276 mutex_lock(&nfsd_mutex);
277 if (nn->nfsd_serv)
278 rv = nn->nfsd_serv->sv_nrthreads;
279 mutex_unlock(&nfsd_mutex);
280 return rv;
281}
282
283static int nfsd_init_socks(struct net *net, const struct cred *cred)
284{
285 int error;
286 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
287
288 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
289 return 0;
290
291 error = svc_xprt_create(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
292 SVC_SOCK_DEFAULTS, cred);
293 if (error < 0)
294 return error;
295
296 error = svc_xprt_create(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
297 SVC_SOCK_DEFAULTS, cred);
298 if (error < 0)
299 return error;
300
301 return 0;
302}
303
304static int nfsd_users = 0;
305
306static int nfsd_startup_generic(void)
307{
308 int ret;
309
310 if (nfsd_users++)
311 return 0;
312
313 ret = nfsd_file_cache_init();
314 if (ret)
315 goto dec_users;
316
317 ret = nfs4_state_start();
318 if (ret)
319 goto out_file_cache;
320 return 0;
321
322out_file_cache:
323 nfsd_file_cache_shutdown();
324dec_users:
325 nfsd_users--;
326 return ret;
327}
328
329static void nfsd_shutdown_generic(void)
330{
331 if (--nfsd_users)
332 return;
333
334 nfs4_state_shutdown();
335 nfsd_file_cache_shutdown();
336}
337
338static bool nfsd_needs_lockd(struct nfsd_net *nn)
339{
340 return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST);
341}
342
343/**
344 * nfsd_copy_write_verifier - Atomically copy a write verifier
345 * @verf: buffer in which to receive the verifier cookie
346 * @nn: NFS net namespace
347 *
348 * This function provides a wait-free mechanism for copying the
349 * namespace's write verifier without tearing it.
350 */
351void nfsd_copy_write_verifier(__be32 verf[2], struct nfsd_net *nn)
352{
353 unsigned int seq;
354
355 do {
356 seq = read_seqbegin(&nn->writeverf_lock);
357 memcpy(verf, nn->writeverf, sizeof(nn->writeverf));
358 } while (read_seqretry(&nn->writeverf_lock, seq));
359}
360
361static void nfsd_reset_write_verifier_locked(struct nfsd_net *nn)
362{
363 struct timespec64 now;
364 u64 verf;
365
366 /*
367 * Because the time value is hashed, y2038 time_t overflow
368 * is irrelevant in this usage.
369 */
370 ktime_get_raw_ts64(&now);
371 verf = siphash_2u64(now.tv_sec, now.tv_nsec, &nn->siphash_key);
372 memcpy(nn->writeverf, &verf, sizeof(nn->writeverf));
373}
374
375/**
376 * nfsd_reset_write_verifier - Generate a new write verifier
377 * @nn: NFS net namespace
378 *
379 * This function updates the ->writeverf field of @nn. This field
380 * contains an opaque cookie that, according to Section 18.32.3 of
381 * RFC 8881, "the client can use to determine whether a server has
382 * changed instance state (e.g., server restart) between a call to
383 * WRITE and a subsequent call to either WRITE or COMMIT. This
384 * cookie MUST be unchanged during a single instance of the NFSv4.1
385 * server and MUST be unique between instances of the NFSv4.1
386 * server."
387 */
388void nfsd_reset_write_verifier(struct nfsd_net *nn)
389{
390 write_seqlock(&nn->writeverf_lock);
391 nfsd_reset_write_verifier_locked(nn);
392 write_sequnlock(&nn->writeverf_lock);
393}
394
395/*
396 * Crank up a set of per-namespace resources for a new NFSD instance,
397 * including lockd, a duplicate reply cache, an open file cache
398 * instance, and a cache of NFSv4 state objects.
399 */
400static int nfsd_startup_net(struct net *net, const struct cred *cred)
401{
402 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
403 int ret;
404
405 if (nn->nfsd_net_up)
406 return 0;
407
408 ret = nfsd_startup_generic();
409 if (ret)
410 return ret;
411 ret = nfsd_init_socks(net, cred);
412 if (ret)
413 goto out_socks;
414
415 if (nfsd_needs_lockd(nn) && !nn->lockd_up) {
416 ret = lockd_up(net, cred);
417 if (ret)
418 goto out_socks;
419 nn->lockd_up = true;
420 }
421
422 ret = nfsd_file_cache_start_net(net);
423 if (ret)
424 goto out_lockd;
425
426 ret = nfsd_reply_cache_init(nn);
427 if (ret)
428 goto out_filecache;
429
430 ret = nfs4_state_start_net(net);
431 if (ret)
432 goto out_reply_cache;
433
434#ifdef CONFIG_NFSD_V4_2_INTER_SSC
435 nfsd4_ssc_init_umount_work(nn);
436#endif
437 nn->nfsd_net_up = true;
438 return 0;
439
440out_reply_cache:
441 nfsd_reply_cache_shutdown(nn);
442out_filecache:
443 nfsd_file_cache_shutdown_net(net);
444out_lockd:
445 if (nn->lockd_up) {
446 lockd_down(net);
447 nn->lockd_up = false;
448 }
449out_socks:
450 nfsd_shutdown_generic();
451 return ret;
452}
453
454static void nfsd_shutdown_net(struct net *net)
455{
456 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
457
458 nfs4_state_shutdown_net(net);
459 nfsd_reply_cache_shutdown(nn);
460 nfsd_file_cache_shutdown_net(net);
461 if (nn->lockd_up) {
462 lockd_down(net);
463 nn->lockd_up = false;
464 }
465 nn->nfsd_net_up = false;
466 nfsd_shutdown_generic();
467}
468
469static DEFINE_SPINLOCK(nfsd_notifier_lock);
470static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
471 void *ptr)
472{
473 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
474 struct net_device *dev = ifa->ifa_dev->dev;
475 struct net *net = dev_net(dev);
476 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
477 struct sockaddr_in sin;
478
479 if (event != NETDEV_DOWN || !nn->nfsd_serv)
480 goto out;
481
482 spin_lock(&nfsd_notifier_lock);
483 if (nn->nfsd_serv) {
484 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
485 sin.sin_family = AF_INET;
486 sin.sin_addr.s_addr = ifa->ifa_local;
487 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
488 }
489 spin_unlock(&nfsd_notifier_lock);
490
491out:
492 return NOTIFY_DONE;
493}
494
495static struct notifier_block nfsd_inetaddr_notifier = {
496 .notifier_call = nfsd_inetaddr_event,
497};
498
499#if IS_ENABLED(CONFIG_IPV6)
500static int nfsd_inet6addr_event(struct notifier_block *this,
501 unsigned long event, void *ptr)
502{
503 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
504 struct net_device *dev = ifa->idev->dev;
505 struct net *net = dev_net(dev);
506 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
507 struct sockaddr_in6 sin6;
508
509 if (event != NETDEV_DOWN || !nn->nfsd_serv)
510 goto out;
511
512 spin_lock(&nfsd_notifier_lock);
513 if (nn->nfsd_serv) {
514 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
515 sin6.sin6_family = AF_INET6;
516 sin6.sin6_addr = ifa->addr;
517 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
518 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
519 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
520 }
521 spin_unlock(&nfsd_notifier_lock);
522
523out:
524 return NOTIFY_DONE;
525}
526
527static struct notifier_block nfsd_inet6addr_notifier = {
528 .notifier_call = nfsd_inet6addr_event,
529};
530#endif
531
532/* Only used under nfsd_mutex, so this atomic may be overkill: */
533static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
534
535/**
536 * nfsd_destroy_serv - tear down NFSD's svc_serv for a namespace
537 * @net: network namespace the NFS service is associated with
538 */
539void nfsd_destroy_serv(struct net *net)
540{
541 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
542 struct svc_serv *serv = nn->nfsd_serv;
543
544 spin_lock(&nfsd_notifier_lock);
545 nn->nfsd_serv = NULL;
546 spin_unlock(&nfsd_notifier_lock);
547
548 /* check if the notifier still has clients */
549 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
550 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
551#if IS_ENABLED(CONFIG_IPV6)
552 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
553#endif
554 }
555
556 svc_xprt_destroy_all(serv, net);
557
558 /*
559 * write_ports can create the server without actually starting
560 * any threads--if we get shut down before any threads are
561 * started, then nfsd_destroy_serv will be run before any of this
562 * other initialization has been done except the rpcb information.
563 */
564 svc_rpcb_cleanup(serv, net);
565 if (!nn->nfsd_net_up)
566 return;
567
568 nfsd_shutdown_net(net);
569 nfsd_export_flush(net);
570 svc_destroy(&serv);
571}
572
573void nfsd_reset_versions(struct nfsd_net *nn)
574{
575 int i;
576
577 for (i = 0; i < NFSD_NRVERS; i++)
578 if (nfsd_vers(nn, i, NFSD_TEST))
579 return;
580
581 for (i = 0; i < NFSD_NRVERS; i++)
582 if (i != 4)
583 nfsd_vers(nn, i, NFSD_SET);
584 else {
585 int minor = 0;
586 while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0)
587 minor++;
588 }
589}
590
591/*
592 * Each session guarantees a negotiated per slot memory cache for replies
593 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
594 * NFSv4.1 server might want to use more memory for a DRC than a machine
595 * with mutiple services.
596 *
597 * Impose a hard limit on the number of pages for the DRC which varies
598 * according to the machines free pages. This is of course only a default.
599 *
600 * For now this is a #defined shift which could be under admin control
601 * in the future.
602 */
603static void set_max_drc(void)
604{
605 #define NFSD_DRC_SIZE_SHIFT 7
606 nfsd_drc_max_mem = (nr_free_buffer_pages()
607 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
608 nfsd_drc_mem_used = 0;
609 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
610}
611
612static int nfsd_get_default_max_blksize(void)
613{
614 struct sysinfo i;
615 unsigned long long target;
616 unsigned long ret;
617
618 si_meminfo(&i);
619 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
620 /*
621 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
622 * machines, but only uses 32K on 128M machines. Bottom out at
623 * 8K on 32M and smaller. Of course, this is only a default.
624 */
625 target >>= 12;
626
627 ret = NFSSVC_MAXBLKSIZE;
628 while (ret > target && ret >= 8*1024*2)
629 ret /= 2;
630 return ret;
631}
632
633void nfsd_shutdown_threads(struct net *net)
634{
635 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
636 struct svc_serv *serv;
637
638 mutex_lock(&nfsd_mutex);
639 serv = nn->nfsd_serv;
640 if (serv == NULL) {
641 mutex_unlock(&nfsd_mutex);
642 return;
643 }
644
645 /* Kill outstanding nfsd threads */
646 svc_set_num_threads(serv, NULL, 0);
647 nfsd_destroy_serv(net);
648 mutex_unlock(&nfsd_mutex);
649}
650
651bool i_am_nfsd(void)
652{
653 return kthread_func(current) == nfsd;
654}
655
656int nfsd_create_serv(struct net *net)
657{
658 int error;
659 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
660 struct svc_serv *serv;
661
662 WARN_ON(!mutex_is_locked(&nfsd_mutex));
663 if (nn->nfsd_serv)
664 return 0;
665
666 if (nfsd_max_blksize == 0)
667 nfsd_max_blksize = nfsd_get_default_max_blksize();
668 nfsd_reset_versions(nn);
669 serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize, nfsd);
670 if (serv == NULL)
671 return -ENOMEM;
672
673 serv->sv_maxconn = nn->max_connections;
674 error = svc_bind(serv, net);
675 if (error < 0) {
676 svc_destroy(&serv);
677 return error;
678 }
679 spin_lock(&nfsd_notifier_lock);
680 nn->nfsd_info.mutex = &nfsd_mutex;
681 nn->nfsd_serv = serv;
682 spin_unlock(&nfsd_notifier_lock);
683
684 set_max_drc();
685 /* check if the notifier is already set */
686 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
687 register_inetaddr_notifier(&nfsd_inetaddr_notifier);
688#if IS_ENABLED(CONFIG_IPV6)
689 register_inet6addr_notifier(&nfsd_inet6addr_notifier);
690#endif
691 }
692 nfsd_reset_write_verifier(nn);
693 return 0;
694}
695
696int nfsd_nrpools(struct net *net)
697{
698 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
699
700 if (nn->nfsd_serv == NULL)
701 return 0;
702 else
703 return nn->nfsd_serv->sv_nrpools;
704}
705
706int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
707{
708 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
709 struct svc_serv *serv = nn->nfsd_serv;
710 int i;
711
712 if (serv)
713 for (i = 0; i < serv->sv_nrpools && i < n; i++)
714 nthreads[i] = atomic_read(&serv->sv_pools[i].sp_nrthreads);
715 return 0;
716}
717
718int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
719{
720 int i = 0;
721 int tot = 0;
722 int err = 0;
723 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
724
725 WARN_ON(!mutex_is_locked(&nfsd_mutex));
726
727 if (nn->nfsd_serv == NULL || n <= 0)
728 return 0;
729
730 if (n > nn->nfsd_serv->sv_nrpools)
731 n = nn->nfsd_serv->sv_nrpools;
732
733 /* enforce a global maximum number of threads */
734 tot = 0;
735 for (i = 0; i < n; i++) {
736 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
737 tot += nthreads[i];
738 }
739 if (tot > NFSD_MAXSERVS) {
740 /* total too large: scale down requested numbers */
741 for (i = 0; i < n && tot > 0; i++) {
742 int new = nthreads[i] * NFSD_MAXSERVS / tot;
743 tot -= (nthreads[i] - new);
744 nthreads[i] = new;
745 }
746 for (i = 0; i < n && tot > 0; i++) {
747 nthreads[i]--;
748 tot--;
749 }
750 }
751
752 /*
753 * There must always be a thread in pool 0; the admin
754 * can't shut down NFS completely using pool_threads.
755 */
756 if (nthreads[0] == 0)
757 nthreads[0] = 1;
758
759 /* apply the new numbers */
760 for (i = 0; i < n; i++) {
761 err = svc_set_num_threads(nn->nfsd_serv,
762 &nn->nfsd_serv->sv_pools[i],
763 nthreads[i]);
764 if (err)
765 break;
766 }
767 return err;
768}
769
770/*
771 * Adjust the number of threads and return the new number of threads.
772 * This is also the function that starts the server if necessary, if
773 * this is the first time nrservs is nonzero.
774 */
775int
776nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
777{
778 int error;
779 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
780 struct svc_serv *serv;
781
782 mutex_lock(&nfsd_mutex);
783 dprintk("nfsd: creating service\n");
784
785 nrservs = max(nrservs, 0);
786 nrservs = min(nrservs, NFSD_MAXSERVS);
787 error = 0;
788
789 if (nrservs == 0 && nn->nfsd_serv == NULL)
790 goto out;
791
792 strscpy(nn->nfsd_name, utsname()->nodename,
793 sizeof(nn->nfsd_name));
794
795 error = nfsd_create_serv(net);
796 if (error)
797 goto out;
798 serv = nn->nfsd_serv;
799
800 error = nfsd_startup_net(net, cred);
801 if (error)
802 goto out_put;
803 error = svc_set_num_threads(serv, NULL, nrservs);
804 if (error)
805 goto out_put;
806 error = serv->sv_nrthreads;
807out_put:
808 if (serv->sv_nrthreads == 0)
809 nfsd_destroy_serv(net);
810out:
811 mutex_unlock(&nfsd_mutex);
812 return error;
813}
814
815#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
816static bool
817nfsd_support_acl_version(int vers)
818{
819 if (vers >= NFSD_ACL_MINVERS && vers < NFSD_ACL_NRVERS)
820 return nfsd_acl_version[vers] != NULL;
821 return false;
822}
823
824static int
825nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp,
826 u32 version, int family, unsigned short proto,
827 unsigned short port)
828{
829 if (!nfsd_support_acl_version(version) ||
830 !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
831 return 0;
832 return svc_generic_rpcbind_set(net, progp, version, family,
833 proto, port);
834}
835
836static __be32
837nfsd_acl_init_request(struct svc_rqst *rqstp,
838 const struct svc_program *progp,
839 struct svc_process_info *ret)
840{
841 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
842 int i;
843
844 if (likely(nfsd_support_acl_version(rqstp->rq_vers) &&
845 nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
846 return svc_generic_init_request(rqstp, progp, ret);
847
848 ret->mismatch.lovers = NFSD_ACL_NRVERS;
849 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) {
850 if (nfsd_support_acl_version(rqstp->rq_vers) &&
851 nfsd_vers(nn, i, NFSD_TEST)) {
852 ret->mismatch.lovers = i;
853 break;
854 }
855 }
856 if (ret->mismatch.lovers == NFSD_ACL_NRVERS)
857 return rpc_prog_unavail;
858 ret->mismatch.hivers = NFSD_ACL_MINVERS;
859 for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) {
860 if (nfsd_support_acl_version(rqstp->rq_vers) &&
861 nfsd_vers(nn, i, NFSD_TEST)) {
862 ret->mismatch.hivers = i;
863 break;
864 }
865 }
866 return rpc_prog_mismatch;
867}
868#endif
869
870static int
871nfsd_rpcbind_set(struct net *net, const struct svc_program *progp,
872 u32 version, int family, unsigned short proto,
873 unsigned short port)
874{
875 if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
876 return 0;
877 return svc_generic_rpcbind_set(net, progp, version, family,
878 proto, port);
879}
880
881static __be32
882nfsd_init_request(struct svc_rqst *rqstp,
883 const struct svc_program *progp,
884 struct svc_process_info *ret)
885{
886 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
887 int i;
888
889 if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
890 return svc_generic_init_request(rqstp, progp, ret);
891
892 ret->mismatch.lovers = NFSD_NRVERS;
893 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
894 if (nfsd_vers(nn, i, NFSD_TEST)) {
895 ret->mismatch.lovers = i;
896 break;
897 }
898 }
899 if (ret->mismatch.lovers == NFSD_NRVERS)
900 return rpc_prog_unavail;
901 ret->mismatch.hivers = NFSD_MINVERS;
902 for (i = NFSD_NRVERS - 1; i >= NFSD_MINVERS; i--) {
903 if (nfsd_vers(nn, i, NFSD_TEST)) {
904 ret->mismatch.hivers = i;
905 break;
906 }
907 }
908 return rpc_prog_mismatch;
909}
910
911/*
912 * This is the NFS server kernel thread
913 */
914static int
915nfsd(void *vrqstp)
916{
917 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
918 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
919 struct net *net = perm_sock->xpt_net;
920 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
921
922 /* At this point, the thread shares current->fs
923 * with the init process. We need to create files with the
924 * umask as defined by the client instead of init's umask. */
925 if (unshare_fs_struct() < 0) {
926 printk("Unable to start nfsd thread: out of memory\n");
927 goto out;
928 }
929
930 current->fs->umask = 0;
931
932 atomic_inc(&nfsdstats.th_cnt);
933
934 set_freezable();
935
936 /*
937 * The main request loop
938 */
939 while (!svc_thread_should_stop(rqstp)) {
940 /* Update sv_maxconn if it has changed */
941 rqstp->rq_server->sv_maxconn = nn->max_connections;
942
943 svc_recv(rqstp);
944 }
945
946 atomic_dec(&nfsdstats.th_cnt);
947
948out:
949 /* Release the thread */
950 svc_exit_thread(rqstp);
951 return 0;
952}
953
954/**
955 * nfsd_dispatch - Process an NFS or NFSACL Request
956 * @rqstp: incoming request
957 *
958 * This RPC dispatcher integrates the NFS server's duplicate reply cache.
959 *
960 * Return values:
961 * %0: Processing complete; do not send a Reply
962 * %1: Processing complete; send Reply in rqstp->rq_res
963 */
964int nfsd_dispatch(struct svc_rqst *rqstp)
965{
966 const struct svc_procedure *proc = rqstp->rq_procinfo;
967 __be32 *statp = rqstp->rq_accept_statp;
968 struct nfsd_cacherep *rp;
969 unsigned int start, len;
970 __be32 *nfs_reply;
971
972 /*
973 * Give the xdr decoder a chance to change this if it wants
974 * (necessary in the NFSv4.0 compound case)
975 */
976 rqstp->rq_cachetype = proc->pc_cachetype;
977
978 /*
979 * ->pc_decode advances the argument stream past the NFS
980 * Call header, so grab the header's starting location and
981 * size now for the call to nfsd_cache_lookup().
982 */
983 start = xdr_stream_pos(&rqstp->rq_arg_stream);
984 len = xdr_stream_remaining(&rqstp->rq_arg_stream);
985 if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream))
986 goto out_decode_err;
987
988 /*
989 * Release rq_status_counter setting it to an odd value after the rpc
990 * request has been properly parsed. rq_status_counter is used to
991 * notify the consumers if the rqstp fields are stable
992 * (rq_status_counter is odd) or not meaningful (rq_status_counter
993 * is even).
994 */
995 smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter | 1);
996
997 rp = NULL;
998 switch (nfsd_cache_lookup(rqstp, start, len, &rp)) {
999 case RC_DOIT:
1000 break;
1001 case RC_REPLY:
1002 goto out_cached_reply;
1003 case RC_DROPIT:
1004 goto out_dropit;
1005 }
1006
1007 nfs_reply = xdr_inline_decode(&rqstp->rq_res_stream, 0);
1008 *statp = proc->pc_func(rqstp);
1009 if (test_bit(RQ_DROPME, &rqstp->rq_flags))
1010 goto out_update_drop;
1011
1012 if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream))
1013 goto out_encode_err;
1014
1015 /*
1016 * Release rq_status_counter setting it to an even value after the rpc
1017 * request has been properly processed.
1018 */
1019 smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter + 1);
1020
1021 nfsd_cache_update(rqstp, rp, rqstp->rq_cachetype, nfs_reply);
1022out_cached_reply:
1023 return 1;
1024
1025out_decode_err:
1026 trace_nfsd_garbage_args_err(rqstp);
1027 *statp = rpc_garbage_args;
1028 return 1;
1029
1030out_update_drop:
1031 nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL);
1032out_dropit:
1033 return 0;
1034
1035out_encode_err:
1036 trace_nfsd_cant_encode_err(rqstp);
1037 nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL);
1038 *statp = rpc_system_err;
1039 return 1;
1040}
1041
1042/**
1043 * nfssvc_decode_voidarg - Decode void arguments
1044 * @rqstp: Server RPC transaction context
1045 * @xdr: XDR stream positioned at arguments to decode
1046 *
1047 * Return values:
1048 * %false: Arguments were not valid
1049 * %true: Decoding was successful
1050 */
1051bool nfssvc_decode_voidarg(struct svc_rqst *rqstp, struct xdr_stream *xdr)
1052{
1053 return true;
1054}
1055
1056/**
1057 * nfssvc_encode_voidres - Encode void results
1058 * @rqstp: Server RPC transaction context
1059 * @xdr: XDR stream into which to encode results
1060 *
1061 * Return values:
1062 * %false: Local error while encoding
1063 * %true: Encoding was successful
1064 */
1065bool nfssvc_encode_voidres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
1066{
1067 return true;
1068}
1069
1070int nfsd_pool_stats_open(struct inode *inode, struct file *file)
1071{
1072 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
1073
1074 return svc_pool_stats_open(&nn->nfsd_info, file);
1075}