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