// SPDX-License-Identifier: GPL-2.0 /* * Central processing for nfsd. * * Authors: Olaf Kirch (okir@monad.swb.de) * * Copyright (C) 1995, 1996, 1997 Olaf Kirch */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "nfsd.h" #include "cache.h" #include "vfs.h" #include "netns.h" #include "filecache.h" #include "trace.h" #define NFSDDBG_FACILITY NFSDDBG_SVC atomic_t nfsd_th_cnt = ATOMIC_INIT(0); static int nfsd(void *vrqstp); #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) static int nfsd_acl_rpcbind_set(struct net *, const struct svc_program *, u32, int, unsigned short, unsigned short); static __be32 nfsd_acl_init_request(struct svc_rqst *, const struct svc_program *, struct svc_process_info *); #endif static int nfsd_rpcbind_set(struct net *, const struct svc_program *, u32, int, unsigned short, unsigned short); static __be32 nfsd_init_request(struct svc_rqst *, const struct svc_program *, struct svc_process_info *); /* * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and some members * of the svc_serv struct such as ->sv_temp_socks and ->sv_permsocks. * * Finally, the nfsd_mutex also protects some of the global variables that are * accessed when nfsd starts and that are settable via the write_* routines in * nfsctl.c. In particular: * * user_recovery_dirname * user_lease_time * nfsd_versions */ DEFINE_MUTEX(nfsd_mutex); /* * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used. * nfsd_drc_max_pages limits the total amount of memory available for * version 4.1 DRC caches. * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage. */ DEFINE_SPINLOCK(nfsd_drc_lock); unsigned long nfsd_drc_max_mem; unsigned long nfsd_drc_mem_used; #if IS_ENABLED(CONFIG_NFS_LOCALIO) static const struct svc_version *localio_versions[] = { [1] = &localio_version1, }; #define NFSD_LOCALIO_NRVERS ARRAY_SIZE(localio_versions) #endif /* CONFIG_NFS_LOCALIO */ #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) static const struct svc_version *nfsd_acl_version[] = { # if defined(CONFIG_NFSD_V2_ACL) [2] = &nfsd_acl_version2, # endif # if defined(CONFIG_NFSD_V3_ACL) [3] = &nfsd_acl_version3, # endif }; #define NFSD_ACL_MINVERS 2 #define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ static const struct svc_version *nfsd_version[NFSD_MAXVERS+1] = { #if defined(CONFIG_NFSD_V2) [2] = &nfsd_version2, #endif [3] = &nfsd_version3, #if defined(CONFIG_NFSD_V4) [4] = &nfsd_version4, #endif }; struct svc_program nfsd_programs[] = { { .pg_prog = NFS_PROGRAM, /* program number */ .pg_nvers = NFSD_MAXVERS+1, /* nr of entries in nfsd_version */ .pg_vers = nfsd_version, /* version table */ .pg_name = "nfsd", /* program name */ .pg_class = "nfsd", /* authentication class */ .pg_authenticate = svc_set_client, /* export authentication */ .pg_init_request = nfsd_init_request, .pg_rpcbind_set = nfsd_rpcbind_set, }, #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) { .pg_prog = NFS_ACL_PROGRAM, .pg_nvers = NFSD_ACL_NRVERS, .pg_vers = nfsd_acl_version, .pg_name = "nfsacl", .pg_class = "nfsd", .pg_authenticate = svc_set_client, .pg_init_request = nfsd_acl_init_request, .pg_rpcbind_set = nfsd_acl_rpcbind_set, }, #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ #if IS_ENABLED(CONFIG_NFS_LOCALIO) { .pg_prog = NFS_LOCALIO_PROGRAM, .pg_nvers = NFSD_LOCALIO_NRVERS, .pg_vers = localio_versions, .pg_name = "nfslocalio", .pg_class = "nfsd", .pg_authenticate = svc_set_client, .pg_init_request = svc_generic_init_request, .pg_rpcbind_set = svc_generic_rpcbind_set, } #endif /* CONFIG_NFS_LOCALIO */ }; bool nfsd_support_version(int vers) { if (vers >= NFSD_MINVERS && vers <= NFSD_MAXVERS) return nfsd_version[vers] != NULL; return false; } int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change) { if (vers < NFSD_MINVERS || vers > NFSD_MAXVERS) return 0; switch(change) { case NFSD_SET: nn->nfsd_versions[vers] = nfsd_support_version(vers); break; case NFSD_CLEAR: nn->nfsd_versions[vers] = false; break; case NFSD_TEST: return nn->nfsd_versions[vers]; case NFSD_AVAIL: return nfsd_support_version(vers); } return 0; } static void nfsd_adjust_nfsd_versions4(struct nfsd_net *nn) { unsigned i; for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) { if (nn->nfsd4_minorversions[i]) return; } nfsd_vers(nn, 4, NFSD_CLEAR); } int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change) { if (minorversion > NFSD_SUPPORTED_MINOR_VERSION && change != NFSD_AVAIL) return -1; switch(change) { case NFSD_SET: nfsd_vers(nn, 4, NFSD_SET); nn->nfsd4_minorversions[minorversion] = nfsd_vers(nn, 4, NFSD_TEST); break; case NFSD_CLEAR: nn->nfsd4_minorversions[minorversion] = false; nfsd_adjust_nfsd_versions4(nn); break; case NFSD_TEST: return nn->nfsd4_minorversions[minorversion]; case NFSD_AVAIL: return minorversion <= NFSD_SUPPORTED_MINOR_VERSION && nfsd_vers(nn, 4, NFSD_AVAIL); } return 0; } bool nfsd_serv_try_get(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); return (nn && percpu_ref_tryget_live(&nn->nfsd_serv_ref)); } void nfsd_serv_put(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); percpu_ref_put(&nn->nfsd_serv_ref); } static void nfsd_serv_done(struct percpu_ref *ref) { struct nfsd_net *nn = container_of(ref, struct nfsd_net, nfsd_serv_ref); complete(&nn->nfsd_serv_confirm_done); } static void nfsd_serv_free(struct percpu_ref *ref) { struct nfsd_net *nn = container_of(ref, struct nfsd_net, nfsd_serv_ref); complete(&nn->nfsd_serv_free_done); } /* * Maximum number of nfsd processes */ #define NFSD_MAXSERVS 8192 int nfsd_nrthreads(struct net *net) { int rv = 0; struct nfsd_net *nn = net_generic(net, nfsd_net_id); mutex_lock(&nfsd_mutex); if (nn->nfsd_serv) rv = nn->nfsd_serv->sv_nrthreads; mutex_unlock(&nfsd_mutex); return rv; } static int nfsd_init_socks(struct net *net, const struct cred *cred) { int error; struct nfsd_net *nn = net_generic(net, nfsd_net_id); if (!list_empty(&nn->nfsd_serv->sv_permsocks)) return 0; error = svc_xprt_create(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT, SVC_SOCK_DEFAULTS, cred); if (error < 0) return error; error = svc_xprt_create(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT, SVC_SOCK_DEFAULTS, cred); if (error < 0) return error; return 0; } static int nfsd_users = 0; static int nfsd_startup_generic(void) { int ret; if (nfsd_users++) return 0; ret = nfsd_file_cache_init(); if (ret) goto dec_users; ret = nfs4_state_start(); if (ret) goto out_file_cache; return 0; out_file_cache: nfsd_file_cache_shutdown(); dec_users: nfsd_users--; return ret; } static void nfsd_shutdown_generic(void) { if (--nfsd_users) return; nfs4_state_shutdown(); nfsd_file_cache_shutdown(); } static bool nfsd_needs_lockd(struct nfsd_net *nn) { return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST); } /** * nfsd_copy_write_verifier - Atomically copy a write verifier * @verf: buffer in which to receive the verifier cookie * @nn: NFS net namespace * * This function provides a wait-free mechanism for copying the * namespace's write verifier without tearing it. */ void nfsd_copy_write_verifier(__be32 verf[2], struct nfsd_net *nn) { unsigned int seq; do { seq = read_seqbegin(&nn->writeverf_lock); memcpy(verf, nn->writeverf, sizeof(nn->writeverf)); } while (read_seqretry(&nn->writeverf_lock, seq)); } static void nfsd_reset_write_verifier_locked(struct nfsd_net *nn) { struct timespec64 now; u64 verf; /* * Because the time value is hashed, y2038 time_t overflow * is irrelevant in this usage. */ ktime_get_raw_ts64(&now); verf = siphash_2u64(now.tv_sec, now.tv_nsec, &nn->siphash_key); memcpy(nn->writeverf, &verf, sizeof(nn->writeverf)); } /** * nfsd_reset_write_verifier - Generate a new write verifier * @nn: NFS net namespace * * This function updates the ->writeverf field of @nn. This field * contains an opaque cookie that, according to Section 18.32.3 of * RFC 8881, "the client can use to determine whether a server has * changed instance state (e.g., server restart) between a call to * WRITE and a subsequent call to either WRITE or COMMIT. This * cookie MUST be unchanged during a single instance of the NFSv4.1 * server and MUST be unique between instances of the NFSv4.1 * server." */ void nfsd_reset_write_verifier(struct nfsd_net *nn) { write_seqlock(&nn->writeverf_lock); nfsd_reset_write_verifier_locked(nn); write_sequnlock(&nn->writeverf_lock); } /* * Crank up a set of per-namespace resources for a new NFSD instance, * including lockd, a duplicate reply cache, an open file cache * instance, and a cache of NFSv4 state objects. */ static int nfsd_startup_net(struct net *net, const struct cred *cred) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); int ret; if (nn->nfsd_net_up) return 0; ret = nfsd_startup_generic(); if (ret) return ret; ret = nfsd_init_socks(net, cred); if (ret) goto out_socks; if (nfsd_needs_lockd(nn) && !nn->lockd_up) { ret = lockd_up(net, cred); if (ret) goto out_socks; nn->lockd_up = true; } ret = nfsd_file_cache_start_net(net); if (ret) goto out_lockd; ret = nfsd_reply_cache_init(nn); if (ret) goto out_filecache; ret = nfs4_state_start_net(net); if (ret) goto out_reply_cache; #ifdef CONFIG_NFSD_V4_2_INTER_SSC nfsd4_ssc_init_umount_work(nn); #endif nn->nfsd_net_up = true; return 0; out_reply_cache: nfsd_reply_cache_shutdown(nn); out_filecache: nfsd_file_cache_shutdown_net(net); out_lockd: if (nn->lockd_up) { lockd_down(net); nn->lockd_up = false; } out_socks: nfsd_shutdown_generic(); return ret; } static void nfsd_shutdown_net(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); nfs4_state_shutdown_net(net); nfsd_reply_cache_shutdown(nn); nfsd_file_cache_shutdown_net(net); if (nn->lockd_up) { lockd_down(net); nn->lockd_up = false; } percpu_ref_exit(&nn->nfsd_serv_ref); nn->nfsd_net_up = false; nfsd_shutdown_generic(); } static DEFINE_SPINLOCK(nfsd_notifier_lock); static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) { struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; struct net_device *dev = ifa->ifa_dev->dev; struct net *net = dev_net(dev); struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct sockaddr_in sin; if (event != NETDEV_DOWN || !nn->nfsd_serv) goto out; spin_lock(&nfsd_notifier_lock); if (nn->nfsd_serv) { dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local); sin.sin_family = AF_INET; sin.sin_addr.s_addr = ifa->ifa_local; svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin); } spin_unlock(&nfsd_notifier_lock); out: return NOTIFY_DONE; } static struct notifier_block nfsd_inetaddr_notifier = { .notifier_call = nfsd_inetaddr_event, }; #if IS_ENABLED(CONFIG_IPV6) static int nfsd_inet6addr_event(struct notifier_block *this, unsigned long event, void *ptr) { struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; struct net_device *dev = ifa->idev->dev; struct net *net = dev_net(dev); struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct sockaddr_in6 sin6; if (event != NETDEV_DOWN || !nn->nfsd_serv) goto out; spin_lock(&nfsd_notifier_lock); if (nn->nfsd_serv) { dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr); sin6.sin6_family = AF_INET6; sin6.sin6_addr = ifa->addr; if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL) sin6.sin6_scope_id = ifa->idev->dev->ifindex; svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6); } spin_unlock(&nfsd_notifier_lock); out: return NOTIFY_DONE; } static struct notifier_block nfsd_inet6addr_notifier = { .notifier_call = nfsd_inet6addr_event, }; #endif /* Only used under nfsd_mutex, so this atomic may be overkill: */ static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0); /** * nfsd_destroy_serv - tear down NFSD's svc_serv for a namespace * @net: network namespace the NFS service is associated with */ void nfsd_destroy_serv(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv = nn->nfsd_serv; lockdep_assert_held(&nfsd_mutex); percpu_ref_kill_and_confirm(&nn->nfsd_serv_ref, nfsd_serv_done); wait_for_completion(&nn->nfsd_serv_confirm_done); wait_for_completion(&nn->nfsd_serv_free_done); /* percpu_ref_exit is called in nfsd_shutdown_net */ spin_lock(&nfsd_notifier_lock); nn->nfsd_serv = NULL; spin_unlock(&nfsd_notifier_lock); /* check if the notifier still has clients */ if (atomic_dec_return(&nfsd_notifier_refcount) == 0) { unregister_inetaddr_notifier(&nfsd_inetaddr_notifier); #if IS_ENABLED(CONFIG_IPV6) unregister_inet6addr_notifier(&nfsd_inet6addr_notifier); #endif } svc_xprt_destroy_all(serv, net); /* * write_ports can create the server without actually starting * any threads--if we get shut down before any threads are * started, then nfsd_destroy_serv will be run before any of this * other initialization has been done except the rpcb information. */ svc_rpcb_cleanup(serv, net); if (!nn->nfsd_net_up) return; nfsd_shutdown_net(net); nfsd_export_flush(net); svc_destroy(&serv); } void nfsd_reset_versions(struct nfsd_net *nn) { int i; for (i = 0; i <= NFSD_MAXVERS; i++) if (nfsd_vers(nn, i, NFSD_TEST)) return; for (i = 0; i <= NFSD_MAXVERS; i++) if (i != 4) nfsd_vers(nn, i, NFSD_SET); else { int minor = 0; while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0) minor++; } } /* * Each session guarantees a negotiated per slot memory cache for replies * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated * NFSv4.1 server might want to use more memory for a DRC than a machine * with mutiple services. * * Impose a hard limit on the number of pages for the DRC which varies * according to the machines free pages. This is of course only a default. * * For now this is a #defined shift which could be under admin control * in the future. */ static void set_max_drc(void) { #define NFSD_DRC_SIZE_SHIFT 7 nfsd_drc_max_mem = (nr_free_buffer_pages() >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE; nfsd_drc_mem_used = 0; dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem); } static int nfsd_get_default_max_blksize(void) { struct sysinfo i; unsigned long long target; unsigned long ret; si_meminfo(&i); target = (i.totalram - i.totalhigh) << PAGE_SHIFT; /* * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig * machines, but only uses 32K on 128M machines. Bottom out at * 8K on 32M and smaller. Of course, this is only a default. */ target >>= 12; ret = NFSSVC_MAXBLKSIZE; while (ret > target && ret >= 8*1024*2) ret /= 2; return ret; } void nfsd_shutdown_threads(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv; mutex_lock(&nfsd_mutex); serv = nn->nfsd_serv; if (serv == NULL) { mutex_unlock(&nfsd_mutex); return; } /* Kill outstanding nfsd threads */ svc_set_num_threads(serv, NULL, 0); nfsd_destroy_serv(net); mutex_unlock(&nfsd_mutex); } struct svc_rqst *nfsd_current_rqst(void) { if (kthread_func(current) == nfsd) return kthread_data(current); return NULL; } int nfsd_create_serv(struct net *net) { int error; struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv; WARN_ON(!mutex_is_locked(&nfsd_mutex)); if (nn->nfsd_serv) return 0; error = percpu_ref_init(&nn->nfsd_serv_ref, nfsd_serv_free, 0, GFP_KERNEL); if (error) return error; init_completion(&nn->nfsd_serv_free_done); init_completion(&nn->nfsd_serv_confirm_done); if (nfsd_max_blksize == 0) nfsd_max_blksize = nfsd_get_default_max_blksize(); nfsd_reset_versions(nn); serv = svc_create_pooled(nfsd_programs, ARRAY_SIZE(nfsd_programs), &nn->nfsd_svcstats, nfsd_max_blksize, nfsd); if (serv == NULL) return -ENOMEM; serv->sv_maxconn = nn->max_connections; error = svc_bind(serv, net); if (error < 0) { svc_destroy(&serv); return error; } spin_lock(&nfsd_notifier_lock); nn->nfsd_serv = serv; spin_unlock(&nfsd_notifier_lock); set_max_drc(); /* check if the notifier is already set */ if (atomic_inc_return(&nfsd_notifier_refcount) == 1) { register_inetaddr_notifier(&nfsd_inetaddr_notifier); #if IS_ENABLED(CONFIG_IPV6) register_inet6addr_notifier(&nfsd_inet6addr_notifier); #endif } nfsd_reset_write_verifier(nn); return 0; } int nfsd_nrpools(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); if (nn->nfsd_serv == NULL) return 0; else return nn->nfsd_serv->sv_nrpools; } int nfsd_get_nrthreads(int n, int *nthreads, struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv = nn->nfsd_serv; int i; if (serv) for (i = 0; i < serv->sv_nrpools && i < n; i++) nthreads[i] = serv->sv_pools[i].sp_nrthreads; return 0; } /** * nfsd_set_nrthreads - set the number of running threads in the net's service * @n: number of array members in @nthreads * @nthreads: array of thread counts for each pool * @net: network namespace to operate within * * This function alters the number of running threads for the given network * namespace in each pool. If passed an array longer then the number of pools * the extra pool settings are ignored. If passed an array shorter than the * number of pools, the missing values are interpreted as 0's. * * Returns 0 on success or a negative errno on error. */ int nfsd_set_nrthreads(int n, int *nthreads, struct net *net) { int i = 0; int tot = 0; int err = 0; struct nfsd_net *nn = net_generic(net, nfsd_net_id); lockdep_assert_held(&nfsd_mutex); if (nn->nfsd_serv == NULL || n <= 0) return 0; /* * Special case: When n == 1, pass in NULL for the pool, so that the * change is distributed equally among them. */ if (n == 1) return svc_set_num_threads(nn->nfsd_serv, NULL, nthreads[0]); if (n > nn->nfsd_serv->sv_nrpools) n = nn->nfsd_serv->sv_nrpools; /* enforce a global maximum number of threads */ tot = 0; for (i = 0; i < n; i++) { nthreads[i] = min(nthreads[i], NFSD_MAXSERVS); tot += nthreads[i]; } if (tot > NFSD_MAXSERVS) { /* total too large: scale down requested numbers */ for (i = 0; i < n && tot > 0; i++) { int new = nthreads[i] * NFSD_MAXSERVS / tot; tot -= (nthreads[i] - new); nthreads[i] = new; } for (i = 0; i < n && tot > 0; i++) { nthreads[i]--; tot--; } } /* apply the new numbers */ for (i = 0; i < n; i++) { err = svc_set_num_threads(nn->nfsd_serv, &nn->nfsd_serv->sv_pools[i], nthreads[i]); if (err) goto out; } /* Anything undefined in array is considered to be 0 */ for (i = n; i < nn->nfsd_serv->sv_nrpools; ++i) { err = svc_set_num_threads(nn->nfsd_serv, &nn->nfsd_serv->sv_pools[i], 0); if (err) goto out; } out: return err; } /** * nfsd_svc: start up or shut down the nfsd server * @n: number of array members in @nthreads * @nthreads: array of thread counts for each pool * @net: network namespace to operate within * @cred: credentials to use for xprt creation * @scope: server scope value (defaults to nodename) * * Adjust the number of threads in each pool and return the new * total number of threads in the service. */ int nfsd_svc(int n, int *nthreads, struct net *net, const struct cred *cred, const char *scope) { int error; struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct svc_serv *serv; lockdep_assert_held(&nfsd_mutex); dprintk("nfsd: creating service\n"); strscpy(nn->nfsd_name, scope ? scope : utsname()->nodename, sizeof(nn->nfsd_name)); error = nfsd_create_serv(net); if (error) goto out; serv = nn->nfsd_serv; error = nfsd_startup_net(net, cred); if (error) goto out_put; error = nfsd_set_nrthreads(n, nthreads, net); if (error) goto out_put; error = serv->sv_nrthreads; out_put: if (serv->sv_nrthreads == 0) nfsd_destroy_serv(net); out: return error; } #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) static bool nfsd_support_acl_version(int vers) { if (vers >= NFSD_ACL_MINVERS && vers < NFSD_ACL_NRVERS) return nfsd_acl_version[vers] != NULL; return false; } static int nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp, u32 version, int family, unsigned short proto, unsigned short port) { if (!nfsd_support_acl_version(version) || !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST)) return 0; return svc_generic_rpcbind_set(net, progp, version, family, proto, port); } static __be32 nfsd_acl_init_request(struct svc_rqst *rqstp, const struct svc_program *progp, struct svc_process_info *ret) { struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); int i; if (likely(nfsd_support_acl_version(rqstp->rq_vers) && nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST))) return svc_generic_init_request(rqstp, progp, ret); ret->mismatch.lovers = NFSD_ACL_NRVERS; for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) { if (nfsd_support_acl_version(rqstp->rq_vers) && nfsd_vers(nn, i, NFSD_TEST)) { ret->mismatch.lovers = i; break; } } if (ret->mismatch.lovers == NFSD_ACL_NRVERS) return rpc_prog_unavail; ret->mismatch.hivers = NFSD_ACL_MINVERS; for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) { if (nfsd_support_acl_version(rqstp->rq_vers) && nfsd_vers(nn, i, NFSD_TEST)) { ret->mismatch.hivers = i; break; } } return rpc_prog_mismatch; } #endif static int nfsd_rpcbind_set(struct net *net, const struct svc_program *progp, u32 version, int family, unsigned short proto, unsigned short port) { if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST)) return 0; return svc_generic_rpcbind_set(net, progp, version, family, proto, port); } static __be32 nfsd_init_request(struct svc_rqst *rqstp, const struct svc_program *progp, struct svc_process_info *ret) { struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); int i; if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST))) return svc_generic_init_request(rqstp, progp, ret); ret->mismatch.lovers = NFSD_MAXVERS + 1; for (i = NFSD_MINVERS; i <= NFSD_MAXVERS; i++) { if (nfsd_vers(nn, i, NFSD_TEST)) { ret->mismatch.lovers = i; break; } } if (ret->mismatch.lovers > NFSD_MAXVERS) return rpc_prog_unavail; ret->mismatch.hivers = NFSD_MINVERS; for (i = NFSD_MAXVERS; i >= NFSD_MINVERS; i--) { if (nfsd_vers(nn, i, NFSD_TEST)) { ret->mismatch.hivers = i; break; } } return rpc_prog_mismatch; } /* * This is the NFS server kernel thread */ static int nfsd(void *vrqstp) { struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list); struct net *net = perm_sock->xpt_net; struct nfsd_net *nn = net_generic(net, nfsd_net_id); /* At this point, the thread shares current->fs * with the init process. We need to create files with the * umask as defined by the client instead of init's umask. */ svc_thread_init_status(rqstp, unshare_fs_struct()); current->fs->umask = 0; atomic_inc(&nfsd_th_cnt); set_freezable(); /* * The main request loop */ while (!svc_thread_should_stop(rqstp)) { /* Update sv_maxconn if it has changed */ rqstp->rq_server->sv_maxconn = nn->max_connections; svc_recv(rqstp); nfsd_file_net_dispose(nn); } atomic_dec(&nfsd_th_cnt); /* Release the thread */ svc_exit_thread(rqstp); return 0; } /** * nfsd_dispatch - Process an NFS or NFSACL or LOCALIO Request * @rqstp: incoming request * * This RPC dispatcher integrates the NFS server's duplicate reply cache. * * Return values: * %0: Processing complete; do not send a Reply * %1: Processing complete; send Reply in rqstp->rq_res */ int nfsd_dispatch(struct svc_rqst *rqstp) { const struct svc_procedure *proc = rqstp->rq_procinfo; __be32 *statp = rqstp->rq_accept_statp; struct nfsd_cacherep *rp; unsigned int start, len; __be32 *nfs_reply; /* * Give the xdr decoder a chance to change this if it wants * (necessary in the NFSv4.0 compound case) */ rqstp->rq_cachetype = proc->pc_cachetype; /* * ->pc_decode advances the argument stream past the NFS * Call header, so grab the header's starting location and * size now for the call to nfsd_cache_lookup(). */ start = xdr_stream_pos(&rqstp->rq_arg_stream); len = xdr_stream_remaining(&rqstp->rq_arg_stream); if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream)) goto out_decode_err; /* * Release rq_status_counter setting it to an odd value after the rpc * request has been properly parsed. rq_status_counter is used to * notify the consumers if the rqstp fields are stable * (rq_status_counter is odd) or not meaningful (rq_status_counter * is even). */ smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter | 1); rp = NULL; switch (nfsd_cache_lookup(rqstp, start, len, &rp)) { case RC_DOIT: break; case RC_REPLY: goto out_cached_reply; case RC_DROPIT: goto out_dropit; } nfs_reply = xdr_inline_decode(&rqstp->rq_res_stream, 0); *statp = proc->pc_func(rqstp); if (test_bit(RQ_DROPME, &rqstp->rq_flags)) goto out_update_drop; if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream)) goto out_encode_err; /* * Release rq_status_counter setting it to an even value after the rpc * request has been properly processed. */ smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter + 1); nfsd_cache_update(rqstp, rp, rqstp->rq_cachetype, nfs_reply); out_cached_reply: return 1; out_decode_err: trace_nfsd_garbage_args_err(rqstp); *statp = rpc_garbage_args; return 1; out_update_drop: nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); out_dropit: return 0; out_encode_err: trace_nfsd_cant_encode_err(rqstp); nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); *statp = rpc_system_err; return 1; } /** * nfssvc_decode_voidarg - Decode void arguments * @rqstp: Server RPC transaction context * @xdr: XDR stream positioned at arguments to decode * * Return values: * %false: Arguments were not valid * %true: Decoding was successful */ bool nfssvc_decode_voidarg(struct svc_rqst *rqstp, struct xdr_stream *xdr) { return true; } /** * nfssvc_encode_voidres - Encode void results * @rqstp: Server RPC transaction context * @xdr: XDR stream into which to encode results * * Return values: * %false: Local error while encoding * %true: Encoding was successful */ bool nfssvc_encode_voidres(struct svc_rqst *rqstp, struct xdr_stream *xdr) { return true; }