1 // SPDX-License-Identifier: GPL-2.0
3 * Central processing for nfsd.
5 * Authors: Olaf Kirch (okir@monad.swb.de)
7 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
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>
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>
26 #include <net/net_namespace.h>
31 #include "filecache.h"
35 #define NFSDDBG_FACILITY NFSDDBG_SVC
37 extern struct svc_program nfsd_program;
38 static int nfsd(void *vrqstp);
39 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
40 static int nfsd_acl_rpcbind_set(struct net *,
41 const struct svc_program *,
45 static __be32 nfsd_acl_init_request(struct svc_rqst *,
46 const struct svc_program *,
47 struct svc_process_info *);
49 static int nfsd_rpcbind_set(struct net *,
50 const struct svc_program *,
54 static __be32 nfsd_init_request(struct svc_rqst *,
55 const struct svc_program *,
56 struct svc_process_info *);
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.
62 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
63 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0 (unless
64 * nn->keep_active is set). That number of nfsd threads must
65 * exist and each must be listed in ->sp_all_threads in some entry of
68 * Each active thread holds a counted reference on nn->nfsd_serv, as does
69 * the nn->keep_active flag and various transient calls to svc_get().
71 * Finally, the nfsd_mutex also protects some of the global variables that are
72 * accessed when nfsd starts and that are settable via the write_* routines in
73 * nfsctl.c. In particular:
75 * user_recovery_dirname
79 DEFINE_MUTEX(nfsd_mutex);
82 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
83 * nfsd_drc_max_pages limits the total amount of memory available for
84 * version 4.1 DRC caches.
85 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
87 DEFINE_SPINLOCK(nfsd_drc_lock);
88 unsigned long nfsd_drc_max_mem;
89 unsigned long nfsd_drc_mem_used;
91 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
92 static struct svc_stat nfsd_acl_svcstats;
93 static const struct svc_version *nfsd_acl_version[] = {
94 [2] = &nfsd_acl_version2,
95 [3] = &nfsd_acl_version3,
98 #define NFSD_ACL_MINVERS 2
99 #define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
101 static struct svc_program nfsd_acl_program = {
102 .pg_prog = NFS_ACL_PROGRAM,
103 .pg_nvers = NFSD_ACL_NRVERS,
104 .pg_vers = nfsd_acl_version,
107 .pg_stats = &nfsd_acl_svcstats,
108 .pg_authenticate = &svc_set_client,
109 .pg_init_request = nfsd_acl_init_request,
110 .pg_rpcbind_set = nfsd_acl_rpcbind_set,
113 static struct svc_stat nfsd_acl_svcstats = {
114 .program = &nfsd_acl_program,
116 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
118 static const struct svc_version *nfsd_version[] = {
119 [2] = &nfsd_version2,
120 #if defined(CONFIG_NFSD_V3)
121 [3] = &nfsd_version3,
123 #if defined(CONFIG_NFSD_V4)
124 [4] = &nfsd_version4,
128 #define NFSD_MINVERS 2
129 #define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
131 struct svc_program nfsd_program = {
132 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
133 .pg_next = &nfsd_acl_program,
135 .pg_prog = NFS_PROGRAM, /* program number */
136 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
137 .pg_vers = nfsd_version, /* version table */
138 .pg_name = "nfsd", /* program name */
139 .pg_class = "nfsd", /* authentication class */
140 .pg_stats = &nfsd_svcstats, /* version table */
141 .pg_authenticate = &svc_set_client, /* export authentication */
142 .pg_init_request = nfsd_init_request,
143 .pg_rpcbind_set = nfsd_rpcbind_set,
147 nfsd_support_version(int vers)
149 if (vers >= NFSD_MINVERS && vers < NFSD_NRVERS)
150 return nfsd_version[vers] != NULL;
155 nfsd_alloc_versions(void)
157 bool *vers = kmalloc_array(NFSD_NRVERS, sizeof(bool), GFP_KERNEL);
161 /* All compiled versions are enabled by default */
162 for (i = 0; i < NFSD_NRVERS; i++)
163 vers[i] = nfsd_support_version(i);
169 nfsd_alloc_minorversions(void)
171 bool *vers = kmalloc_array(NFSD_SUPPORTED_MINOR_VERSION + 1,
172 sizeof(bool), GFP_KERNEL);
176 /* All minor versions are enabled by default */
177 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++)
178 vers[i] = nfsd_support_version(4);
184 nfsd_netns_free_versions(struct nfsd_net *nn)
186 kfree(nn->nfsd_versions);
187 kfree(nn->nfsd4_minorversions);
188 nn->nfsd_versions = NULL;
189 nn->nfsd4_minorversions = NULL;
193 nfsd_netns_init_versions(struct nfsd_net *nn)
195 if (!nn->nfsd_versions) {
196 nn->nfsd_versions = nfsd_alloc_versions();
197 nn->nfsd4_minorversions = nfsd_alloc_minorversions();
198 if (!nn->nfsd_versions || !nn->nfsd4_minorversions)
199 nfsd_netns_free_versions(nn);
203 int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change)
205 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
209 if (nn->nfsd_versions)
210 nn->nfsd_versions[vers] = nfsd_support_version(vers);
213 nfsd_netns_init_versions(nn);
214 if (nn->nfsd_versions)
215 nn->nfsd_versions[vers] = false;
218 if (nn->nfsd_versions)
219 return nn->nfsd_versions[vers];
222 return nfsd_support_version(vers);
228 nfsd_adjust_nfsd_versions4(struct nfsd_net *nn)
232 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
233 if (nn->nfsd4_minorversions[i])
236 nfsd_vers(nn, 4, NFSD_CLEAR);
239 int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change)
241 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
242 change != NFSD_AVAIL)
247 if (nn->nfsd4_minorversions) {
248 nfsd_vers(nn, 4, NFSD_SET);
249 nn->nfsd4_minorversions[minorversion] =
250 nfsd_vers(nn, 4, NFSD_TEST);
254 nfsd_netns_init_versions(nn);
255 if (nn->nfsd4_minorversions) {
256 nn->nfsd4_minorversions[minorversion] = false;
257 nfsd_adjust_nfsd_versions4(nn);
261 if (nn->nfsd4_minorversions)
262 return nn->nfsd4_minorversions[minorversion];
263 return nfsd_vers(nn, 4, NFSD_TEST);
265 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION &&
266 nfsd_vers(nn, 4, NFSD_AVAIL);
272 * Maximum number of nfsd processes
274 #define NFSD_MAXSERVS 8192
276 int nfsd_nrthreads(struct net *net)
279 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
281 mutex_lock(&nfsd_mutex);
283 rv = nn->nfsd_serv->sv_nrthreads;
284 mutex_unlock(&nfsd_mutex);
288 static int nfsd_init_socks(struct net *net, const struct cred *cred)
291 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
293 if (!list_empty(&nn->nfsd_serv->sv_permsocks))
296 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
297 SVC_SOCK_DEFAULTS, cred);
301 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
302 SVC_SOCK_DEFAULTS, cred);
309 static int nfsd_users = 0;
311 static int nfsd_startup_generic(void)
318 ret = nfsd_file_cache_init();
322 ret = nfs4_state_start();
328 nfsd_file_cache_shutdown();
334 static void nfsd_shutdown_generic(void)
339 nfs4_state_shutdown();
340 nfsd_file_cache_shutdown();
343 static bool nfsd_needs_lockd(struct nfsd_net *nn)
345 return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST);
349 * nfsd_copy_write_verifier - Atomically copy a write verifier
350 * @verf: buffer in which to receive the verifier cookie
351 * @nn: NFS net namespace
353 * This function provides a wait-free mechanism for copying the
354 * namespace's write verifier without tearing it.
356 void nfsd_copy_write_verifier(__be32 verf[2], struct nfsd_net *nn)
361 read_seqbegin_or_lock(&nn->writeverf_lock, &seq);
362 memcpy(verf, nn->writeverf, sizeof(*verf));
363 } while (need_seqretry(&nn->writeverf_lock, seq));
364 done_seqretry(&nn->writeverf_lock, seq);
367 static void nfsd_reset_write_verifier_locked(struct nfsd_net *nn)
369 struct timespec64 now;
373 * Because the time value is hashed, y2038 time_t overflow
374 * is irrelevant in this usage.
376 ktime_get_raw_ts64(&now);
377 verf = siphash_2u64(now.tv_sec, now.tv_nsec, &nn->siphash_key);
378 memcpy(nn->writeverf, &verf, sizeof(nn->writeverf));
382 * nfsd_reset_write_verifier - Generate a new write verifier
383 * @nn: NFS net namespace
385 * This function updates the ->writeverf field of @nn. This field
386 * contains an opaque cookie that, according to Section 18.32.3 of
387 * RFC 8881, "the client can use to determine whether a server has
388 * changed instance state (e.g., server restart) between a call to
389 * WRITE and a subsequent call to either WRITE or COMMIT. This
390 * cookie MUST be unchanged during a single instance of the NFSv4.1
391 * server and MUST be unique between instances of the NFSv4.1
394 void nfsd_reset_write_verifier(struct nfsd_net *nn)
396 write_seqlock(&nn->writeverf_lock);
397 nfsd_reset_write_verifier_locked(nn);
398 write_sequnlock(&nn->writeverf_lock);
401 static int nfsd_startup_net(struct net *net, const struct cred *cred)
403 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
409 ret = nfsd_startup_generic();
412 ret = nfsd_init_socks(net, cred);
416 if (nfsd_needs_lockd(nn) && !nn->lockd_up) {
417 ret = lockd_up(net, cred);
423 ret = nfsd_file_cache_start_net(net);
426 ret = nfs4_state_start_net(net);
430 #ifdef CONFIG_NFSD_V4_2_INTER_SSC
431 nfsd4_ssc_init_umount_work(nn);
433 nn->nfsd_net_up = true;
437 nfsd_file_cache_shutdown_net(net);
441 nn->lockd_up = false;
444 nfsd_shutdown_generic();
448 static void nfsd_shutdown_net(struct net *net)
450 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
452 nfsd_file_cache_shutdown_net(net);
453 nfs4_state_shutdown_net(net);
456 nn->lockd_up = false;
458 nn->nfsd_net_up = false;
459 nfsd_shutdown_generic();
462 static DEFINE_SPINLOCK(nfsd_notifier_lock);
463 static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
466 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
467 struct net_device *dev = ifa->ifa_dev->dev;
468 struct net *net = dev_net(dev);
469 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
470 struct sockaddr_in sin;
472 if (event != NETDEV_DOWN || !nn->nfsd_serv)
475 spin_lock(&nfsd_notifier_lock);
477 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
478 sin.sin_family = AF_INET;
479 sin.sin_addr.s_addr = ifa->ifa_local;
480 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
482 spin_unlock(&nfsd_notifier_lock);
488 static struct notifier_block nfsd_inetaddr_notifier = {
489 .notifier_call = nfsd_inetaddr_event,
492 #if IS_ENABLED(CONFIG_IPV6)
493 static int nfsd_inet6addr_event(struct notifier_block *this,
494 unsigned long event, void *ptr)
496 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
497 struct net_device *dev = ifa->idev->dev;
498 struct net *net = dev_net(dev);
499 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
500 struct sockaddr_in6 sin6;
502 if (event != NETDEV_DOWN || !nn->nfsd_serv)
505 spin_lock(&nfsd_notifier_lock);
507 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
508 sin6.sin6_family = AF_INET6;
509 sin6.sin6_addr = ifa->addr;
510 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
511 sin6.sin6_scope_id = ifa->idev->dev->ifindex;
512 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
514 spin_unlock(&nfsd_notifier_lock);
520 static struct notifier_block nfsd_inet6addr_notifier = {
521 .notifier_call = nfsd_inet6addr_event,
525 /* Only used under nfsd_mutex, so this atomic may be overkill: */
526 static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
528 static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
530 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
532 /* check if the notifier still has clients */
533 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
534 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
535 #if IS_ENABLED(CONFIG_IPV6)
536 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
541 * write_ports can create the server without actually starting
542 * any threads--if we get shut down before any threads are
543 * started, then nfsd_last_thread will be run before any of this
544 * other initialization has been done except the rpcb information.
546 svc_rpcb_cleanup(serv, net);
547 if (!nn->nfsd_net_up)
550 nfsd_shutdown_net(net);
551 pr_info("nfsd: last server has exited, flushing export cache\n");
552 nfsd_export_flush(net);
555 void nfsd_reset_versions(struct nfsd_net *nn)
559 for (i = 0; i < NFSD_NRVERS; i++)
560 if (nfsd_vers(nn, i, NFSD_TEST))
563 for (i = 0; i < NFSD_NRVERS; i++)
565 nfsd_vers(nn, i, NFSD_SET);
568 while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0)
574 * Each session guarantees a negotiated per slot memory cache for replies
575 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
576 * NFSv4.1 server might want to use more memory for a DRC than a machine
577 * with mutiple services.
579 * Impose a hard limit on the number of pages for the DRC which varies
580 * according to the machines free pages. This is of course only a default.
582 * For now this is a #defined shift which could be under admin control
585 static void set_max_drc(void)
587 #define NFSD_DRC_SIZE_SHIFT 7
588 nfsd_drc_max_mem = (nr_free_buffer_pages()
589 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
590 nfsd_drc_mem_used = 0;
591 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
594 static int nfsd_get_default_max_blksize(void)
597 unsigned long long target;
601 target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
603 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
604 * machines, but only uses 32K on 128M machines. Bottom out at
605 * 8K on 32M and smaller. Of course, this is only a default.
609 ret = NFSSVC_MAXBLKSIZE;
610 while (ret > target && ret >= 8*1024*2)
615 static const struct svc_serv_ops nfsd_thread_sv_ops = {
616 .svo_shutdown = nfsd_last_thread,
617 .svo_function = nfsd,
618 .svo_enqueue_xprt = svc_xprt_do_enqueue,
619 .svo_module = THIS_MODULE,
622 void nfsd_shutdown_threads(struct net *net)
624 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
625 struct svc_serv *serv;
627 mutex_lock(&nfsd_mutex);
628 serv = nn->nfsd_serv;
630 mutex_unlock(&nfsd_mutex);
635 /* Kill outstanding nfsd threads */
636 svc_set_num_threads(serv, NULL, 0);
638 mutex_unlock(&nfsd_mutex);
643 return kthread_func(current) == nfsd;
646 int nfsd_create_serv(struct net *net)
649 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
650 struct svc_serv *serv;
652 WARN_ON(!mutex_is_locked(&nfsd_mutex));
654 svc_get(nn->nfsd_serv);
657 if (nfsd_max_blksize == 0)
658 nfsd_max_blksize = nfsd_get_default_max_blksize();
659 nfsd_reset_versions(nn);
660 serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
661 &nfsd_thread_sv_ops);
665 serv->sv_maxconn = nn->max_connections;
666 error = svc_bind(serv, net);
668 /* NOT nfsd_put() as notifiers (see below) haven't
674 spin_lock(&nfsd_notifier_lock);
675 nn->nfsd_serv = serv;
676 spin_unlock(&nfsd_notifier_lock);
679 /* check if the notifier is already set */
680 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
681 register_inetaddr_notifier(&nfsd_inetaddr_notifier);
682 #if IS_ENABLED(CONFIG_IPV6)
683 register_inet6addr_notifier(&nfsd_inet6addr_notifier);
686 nfsd_reset_write_verifier(nn);
690 int nfsd_nrpools(struct net *net)
692 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
694 if (nn->nfsd_serv == NULL)
697 return nn->nfsd_serv->sv_nrpools;
700 int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
703 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
705 if (nn->nfsd_serv != NULL) {
706 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
707 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
713 /* This is the callback for kref_put() below.
714 * There is no code here as the first thing to be done is
715 * call svc_shutdown_net(), but we cannot get the 'net' from
716 * the kref. So do all the work when kref_put returns true.
718 static void nfsd_noop(struct kref *ref)
722 void nfsd_put(struct net *net)
724 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
726 if (kref_put(&nn->nfsd_serv->sv_refcnt, nfsd_noop)) {
727 svc_shutdown_net(nn->nfsd_serv, net);
728 svc_destroy(&nn->nfsd_serv->sv_refcnt);
729 spin_lock(&nfsd_notifier_lock);
730 nn->nfsd_serv = NULL;
731 spin_unlock(&nfsd_notifier_lock);
735 int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
740 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
742 WARN_ON(!mutex_is_locked(&nfsd_mutex));
744 if (nn->nfsd_serv == NULL || n <= 0)
747 if (n > nn->nfsd_serv->sv_nrpools)
748 n = nn->nfsd_serv->sv_nrpools;
750 /* enforce a global maximum number of threads */
752 for (i = 0; i < n; i++) {
753 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
756 if (tot > NFSD_MAXSERVS) {
757 /* total too large: scale down requested numbers */
758 for (i = 0; i < n && tot > 0; i++) {
759 int new = nthreads[i] * NFSD_MAXSERVS / tot;
760 tot -= (nthreads[i] - new);
763 for (i = 0; i < n && tot > 0; i++) {
770 * There must always be a thread in pool 0; the admin
771 * can't shut down NFS completely using pool_threads.
773 if (nthreads[0] == 0)
776 /* apply the new numbers */
777 svc_get(nn->nfsd_serv);
778 for (i = 0; i < n; i++) {
779 err = svc_set_num_threads(nn->nfsd_serv,
780 &nn->nfsd_serv->sv_pools[i],
790 * Adjust the number of threads and return the new number of threads.
791 * This is also the function that starts the server if necessary, if
792 * this is the first time nrservs is nonzero.
795 nfsd_svc(int nrservs, struct net *net, const struct cred *cred)
799 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
801 mutex_lock(&nfsd_mutex);
802 dprintk("nfsd: creating service\n");
804 nrservs = max(nrservs, 0);
805 nrservs = min(nrservs, NFSD_MAXSERVS);
808 if (nrservs == 0 && nn->nfsd_serv == NULL)
811 strlcpy(nn->nfsd_name, utsname()->nodename,
812 sizeof(nn->nfsd_name));
814 error = nfsd_create_serv(net);
818 nfsd_up_before = nn->nfsd_net_up;
820 error = nfsd_startup_net(net, cred);
823 error = svc_set_num_threads(nn->nfsd_serv, NULL, nrservs);
826 error = nn->nfsd_serv->sv_nrthreads;
828 if (error < 0 && !nfsd_up_before)
829 nfsd_shutdown_net(net);
831 /* Threads now hold service active */
832 if (xchg(&nn->keep_active, 0))
836 mutex_unlock(&nfsd_mutex);
840 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
842 nfsd_support_acl_version(int vers)
844 if (vers >= NFSD_ACL_MINVERS && vers < NFSD_ACL_NRVERS)
845 return nfsd_acl_version[vers] != NULL;
850 nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp,
851 u32 version, int family, unsigned short proto,
854 if (!nfsd_support_acl_version(version) ||
855 !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
857 return svc_generic_rpcbind_set(net, progp, version, family,
862 nfsd_acl_init_request(struct svc_rqst *rqstp,
863 const struct svc_program *progp,
864 struct svc_process_info *ret)
866 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
869 if (likely(nfsd_support_acl_version(rqstp->rq_vers) &&
870 nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
871 return svc_generic_init_request(rqstp, progp, ret);
873 ret->mismatch.lovers = NFSD_ACL_NRVERS;
874 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) {
875 if (nfsd_support_acl_version(rqstp->rq_vers) &&
876 nfsd_vers(nn, i, NFSD_TEST)) {
877 ret->mismatch.lovers = i;
881 if (ret->mismatch.lovers == NFSD_ACL_NRVERS)
882 return rpc_prog_unavail;
883 ret->mismatch.hivers = NFSD_ACL_MINVERS;
884 for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) {
885 if (nfsd_support_acl_version(rqstp->rq_vers) &&
886 nfsd_vers(nn, i, NFSD_TEST)) {
887 ret->mismatch.hivers = i;
891 return rpc_prog_mismatch;
896 nfsd_rpcbind_set(struct net *net, const struct svc_program *progp,
897 u32 version, int family, unsigned short proto,
900 if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
902 return svc_generic_rpcbind_set(net, progp, version, family,
907 nfsd_init_request(struct svc_rqst *rqstp,
908 const struct svc_program *progp,
909 struct svc_process_info *ret)
911 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
914 if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
915 return svc_generic_init_request(rqstp, progp, ret);
917 ret->mismatch.lovers = NFSD_NRVERS;
918 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
919 if (nfsd_vers(nn, i, NFSD_TEST)) {
920 ret->mismatch.lovers = i;
924 if (ret->mismatch.lovers == NFSD_NRVERS)
925 return rpc_prog_unavail;
926 ret->mismatch.hivers = NFSD_MINVERS;
927 for (i = NFSD_NRVERS - 1; i >= NFSD_MINVERS; i--) {
928 if (nfsd_vers(nn, i, NFSD_TEST)) {
929 ret->mismatch.hivers = i;
933 return rpc_prog_mismatch;
937 * This is the NFS server kernel thread
942 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
943 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
944 struct net *net = perm_sock->xpt_net;
945 struct nfsd_net *nn = net_generic(net, nfsd_net_id);
948 /* At this point, the thread shares current->fs
949 * with the init process. We need to create files with the
950 * umask as defined by the client instead of init's umask. */
951 if (unshare_fs_struct() < 0) {
952 printk("Unable to start nfsd thread: out of memory\n");
956 current->fs->umask = 0;
959 * thread is spawned with all signals set to SIG_IGN, re-enable
960 * the ones that will bring down the thread
962 allow_signal(SIGKILL);
963 allow_signal(SIGHUP);
964 allow_signal(SIGINT);
965 allow_signal(SIGQUIT);
967 atomic_inc(&nfsdstats.th_cnt);
972 * The main request loop
975 /* Update sv_maxconn if it has changed */
976 rqstp->rq_server->sv_maxconn = nn->max_connections;
979 * Find a socket with data available and call its
982 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
986 validate_process_creds();
988 validate_process_creds();
991 /* Clear signals before calling svc_exit_thread() */
992 flush_signals(current);
994 atomic_dec(&nfsdstats.th_cnt);
997 /* Take an extra ref so that the svc_put in svc_exit_thread()
998 * doesn't call svc_destroy()
1000 svc_get(nn->nfsd_serv);
1002 /* Release the thread */
1003 svc_exit_thread(rqstp);
1005 /* We need to drop a ref, but may not drop the last reference
1006 * without holding nfsd_mutex, and we cannot wait for nfsd_mutex as that
1007 * could deadlock with nfsd_shutdown_threads() waiting for us.
1008 * So three options are:
1009 * - drop a non-final reference,
1010 * - get the mutex without waiting
1011 * - sleep briefly andd try the above again
1013 while (!svc_put_not_last(nn->nfsd_serv)) {
1014 if (mutex_trylock(&nfsd_mutex)) {
1016 mutex_unlock(&nfsd_mutex);
1022 /* Release module */
1023 module_put_and_kthread_exit(0);
1028 * nfsd_dispatch - Process an NFS or NFSACL Request
1029 * @rqstp: incoming request
1030 * @statp: pointer to location of accept_stat field in RPC Reply buffer
1032 * This RPC dispatcher integrates the NFS server's duplicate reply cache.
1035 * %0: Processing complete; do not send a Reply
1036 * %1: Processing complete; send Reply in rqstp->rq_res
1038 int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
1040 const struct svc_procedure *proc = rqstp->rq_procinfo;
1043 * Give the xdr decoder a chance to change this if it wants
1044 * (necessary in the NFSv4.0 compound case)
1046 rqstp->rq_cachetype = proc->pc_cachetype;
1048 svcxdr_init_decode(rqstp);
1049 if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream))
1050 goto out_decode_err;
1052 switch (nfsd_cache_lookup(rqstp)) {
1056 goto out_cached_reply;
1062 * Need to grab the location to store the status, as
1063 * NFSv4 does some encoding while processing
1065 svcxdr_init_encode(rqstp);
1067 *statp = proc->pc_func(rqstp);
1068 if (*statp == rpc_drop_reply || test_bit(RQ_DROPME, &rqstp->rq_flags))
1069 goto out_update_drop;
1071 if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream))
1072 goto out_encode_err;
1074 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
1079 trace_nfsd_garbage_args_err(rqstp);
1080 *statp = rpc_garbage_args;
1084 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
1089 trace_nfsd_cant_encode_err(rqstp);
1090 nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
1091 *statp = rpc_system_err;
1096 * nfssvc_decode_voidarg - Decode void arguments
1097 * @rqstp: Server RPC transaction context
1098 * @xdr: XDR stream positioned at arguments to decode
1101 * %false: Arguments were not valid
1102 * %true: Decoding was successful
1104 bool nfssvc_decode_voidarg(struct svc_rqst *rqstp, struct xdr_stream *xdr)
1110 * nfssvc_encode_voidres - Encode void results
1111 * @rqstp: Server RPC transaction context
1112 * @xdr: XDR stream into which to encode results
1115 * %false: Local error while encoding
1116 * %true: Encoding was successful
1118 bool nfssvc_encode_voidres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
1123 int nfsd_pool_stats_open(struct inode *inode, struct file *file)
1126 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
1128 mutex_lock(&nfsd_mutex);
1129 if (nn->nfsd_serv == NULL) {
1130 mutex_unlock(&nfsd_mutex);
1133 svc_get(nn->nfsd_serv);
1134 ret = svc_pool_stats_open(nn->nfsd_serv, file);
1135 mutex_unlock(&nfsd_mutex);
1139 int nfsd_pool_stats_release(struct inode *inode, struct file *file)
1141 int ret = seq_release(inode, file);
1142 struct net *net = inode->i_sb->s_fs_info;
1144 mutex_lock(&nfsd_mutex);
1146 mutex_unlock(&nfsd_mutex);