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/nfslocalio.h> 23 #include <linux/seq_file.h> 24 #include <linux/inetdevice.h> 25 #include <net/addrconf.h> 26 #include <net/ipv6.h> 27 #include <net/net_namespace.h> 28 #include "nfsd.h" 29 #include "cache.h" 30 #include "vfs.h" 31 #include "netns.h" 32 #include "filecache.h" 33 34 #include "trace.h" 35 36 #define NFSDDBG_FACILITY NFSDDBG_SVC 37 38 atomic_t nfsd_th_cnt = ATOMIC_INIT(0); 39 static int nfsd(void *vrqstp); 40 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 41 static int nfsd_acl_rpcbind_set(struct net *, 42 const struct svc_program *, 43 u32, int, 44 unsigned short, 45 unsigned short); 46 static __be32 nfsd_acl_init_request(struct svc_rqst *, 47 const struct svc_program *, 48 struct svc_process_info *); 49 #endif 50 static int nfsd_rpcbind_set(struct net *, 51 const struct svc_program *, 52 u32, int, 53 unsigned short, 54 unsigned short); 55 static __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 */ 71 DEFINE_MUTEX(nfsd_mutex); 72 73 #if IS_ENABLED(CONFIG_NFS_LOCALIO) 74 static const struct svc_version *localio_versions[] = { 75 [1] = &localio_version1, 76 }; 77 78 #define NFSD_LOCALIO_NRVERS ARRAY_SIZE(localio_versions) 79 80 #endif /* CONFIG_NFS_LOCALIO */ 81 82 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 83 static const struct svc_version *nfsd_acl_version[] = { 84 # if defined(CONFIG_NFSD_V2_ACL) 85 [2] = &nfsd_acl_version2, 86 # endif 87 # if defined(CONFIG_NFSD_V3_ACL) 88 [3] = &nfsd_acl_version3, 89 # endif 90 }; 91 92 #define NFSD_ACL_MINVERS 2 93 #define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) 94 95 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ 96 97 static const struct svc_version *nfsd_version[NFSD_MAXVERS+1] = { 98 #if defined(CONFIG_NFSD_V2) 99 [2] = &nfsd_version2, 100 #endif 101 [3] = &nfsd_version3, 102 #if defined(CONFIG_NFSD_V4) 103 [4] = &nfsd_version4, 104 #endif 105 }; 106 107 struct svc_program nfsd_programs[] = { 108 { 109 .pg_prog = NFS_PROGRAM, /* program number */ 110 .pg_nvers = NFSD_MAXVERS+1, /* nr of entries in nfsd_version */ 111 .pg_vers = nfsd_version, /* version table */ 112 .pg_name = "nfsd", /* program name */ 113 .pg_class = "nfsd", /* authentication class */ 114 .pg_authenticate = svc_set_client, /* export authentication */ 115 .pg_init_request = nfsd_init_request, 116 .pg_rpcbind_set = nfsd_rpcbind_set, 117 }, 118 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 119 { 120 .pg_prog = NFS_ACL_PROGRAM, 121 .pg_nvers = NFSD_ACL_NRVERS, 122 .pg_vers = nfsd_acl_version, 123 .pg_name = "nfsacl", 124 .pg_class = "nfsd", 125 .pg_authenticate = svc_set_client, 126 .pg_init_request = nfsd_acl_init_request, 127 .pg_rpcbind_set = nfsd_acl_rpcbind_set, 128 }, 129 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ 130 #if IS_ENABLED(CONFIG_NFS_LOCALIO) 131 { 132 .pg_prog = NFS_LOCALIO_PROGRAM, 133 .pg_nvers = NFSD_LOCALIO_NRVERS, 134 .pg_vers = localio_versions, 135 .pg_name = "nfslocalio", 136 .pg_class = "nfsd", 137 .pg_authenticate = svc_set_client, 138 .pg_init_request = svc_generic_init_request, 139 .pg_rpcbind_set = svc_generic_rpcbind_set, 140 } 141 #endif /* CONFIG_NFS_LOCALIO */ 142 }; 143 144 bool nfsd_support_version(int vers) 145 { 146 if (vers >= NFSD_MINVERS && vers <= NFSD_MAXVERS) 147 return nfsd_version[vers] != NULL; 148 return false; 149 } 150 151 int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change) 152 { 153 if (vers < NFSD_MINVERS || vers > NFSD_MAXVERS) 154 return 0; 155 switch(change) { 156 case NFSD_SET: 157 nn->nfsd_versions[vers] = nfsd_support_version(vers); 158 break; 159 case NFSD_CLEAR: 160 nn->nfsd_versions[vers] = false; 161 break; 162 case NFSD_TEST: 163 return nn->nfsd_versions[vers]; 164 case NFSD_AVAIL: 165 return nfsd_support_version(vers); 166 } 167 return 0; 168 } 169 170 static void 171 nfsd_adjust_nfsd_versions4(struct nfsd_net *nn) 172 { 173 unsigned i; 174 175 for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) { 176 if (nn->nfsd4_minorversions[i]) 177 return; 178 } 179 nfsd_vers(nn, 4, NFSD_CLEAR); 180 } 181 182 int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change) 183 { 184 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION && 185 change != NFSD_AVAIL) 186 return -1; 187 188 switch(change) { 189 case NFSD_SET: 190 nfsd_vers(nn, 4, NFSD_SET); 191 nn->nfsd4_minorversions[minorversion] = 192 nfsd_vers(nn, 4, NFSD_TEST); 193 break; 194 case NFSD_CLEAR: 195 nn->nfsd4_minorversions[minorversion] = false; 196 nfsd_adjust_nfsd_versions4(nn); 197 break; 198 case NFSD_TEST: 199 return nn->nfsd4_minorversions[minorversion]; 200 case NFSD_AVAIL: 201 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION && 202 nfsd_vers(nn, 4, NFSD_AVAIL); 203 } 204 return 0; 205 } 206 207 bool nfsd_net_try_get(struct net *net) __must_hold(rcu) 208 { 209 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 210 211 return (nn && percpu_ref_tryget_live(&nn->nfsd_net_ref)); 212 } 213 214 void nfsd_net_put(struct net *net) __must_hold(rcu) 215 { 216 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 217 218 percpu_ref_put(&nn->nfsd_net_ref); 219 } 220 221 static void nfsd_net_done(struct percpu_ref *ref) 222 { 223 struct nfsd_net *nn = container_of(ref, struct nfsd_net, nfsd_net_ref); 224 225 complete(&nn->nfsd_net_confirm_done); 226 } 227 228 static void nfsd_net_free(struct percpu_ref *ref) 229 { 230 struct nfsd_net *nn = container_of(ref, struct nfsd_net, nfsd_net_ref); 231 232 complete(&nn->nfsd_net_free_done); 233 } 234 235 /* 236 * Maximum number of nfsd processes 237 */ 238 #define NFSD_MAXSERVS 8192 239 240 int nfsd_nrthreads(struct net *net) 241 { 242 int rv = 0; 243 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 244 245 mutex_lock(&nfsd_mutex); 246 if (nn->nfsd_serv) 247 rv = nn->nfsd_serv->sv_nrthreads; 248 mutex_unlock(&nfsd_mutex); 249 return rv; 250 } 251 252 static int nfsd_init_socks(struct net *net, const struct cred *cred) 253 { 254 int error; 255 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 256 257 if (!list_empty(&nn->nfsd_serv->sv_permsocks)) 258 return 0; 259 260 error = svc_xprt_create(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT, 261 SVC_SOCK_DEFAULTS, cred); 262 if (error < 0) 263 return error; 264 265 error = svc_xprt_create(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT, 266 SVC_SOCK_DEFAULTS, cred); 267 if (error < 0) 268 return error; 269 270 return 0; 271 } 272 273 static int nfsd_users = 0; 274 275 static int nfsd_startup_generic(void) 276 { 277 int ret; 278 279 if (nfsd_users++) 280 return 0; 281 282 ret = nfsd_file_cache_init(); 283 if (ret) 284 goto dec_users; 285 286 ret = nfs4_state_start(); 287 if (ret) 288 goto out_file_cache; 289 return 0; 290 291 out_file_cache: 292 nfsd_file_cache_shutdown(); 293 dec_users: 294 nfsd_users--; 295 return ret; 296 } 297 298 static void nfsd_shutdown_generic(void) 299 { 300 if (--nfsd_users) 301 return; 302 303 nfs4_state_shutdown(); 304 nfsd_file_cache_shutdown(); 305 } 306 307 static bool nfsd_needs_lockd(struct nfsd_net *nn) 308 { 309 return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST); 310 } 311 312 /** 313 * nfsd_copy_write_verifier - Atomically copy a write verifier 314 * @verf: buffer in which to receive the verifier cookie 315 * @nn: NFS net namespace 316 * 317 * This function provides a wait-free mechanism for copying the 318 * namespace's write verifier without tearing it. 319 */ 320 void nfsd_copy_write_verifier(__be32 verf[2], struct nfsd_net *nn) 321 { 322 unsigned int seq; 323 324 do { 325 seq = read_seqbegin(&nn->writeverf_lock); 326 memcpy(verf, nn->writeverf, sizeof(nn->writeverf)); 327 } while (read_seqretry(&nn->writeverf_lock, seq)); 328 } 329 330 static void nfsd_reset_write_verifier_locked(struct nfsd_net *nn) 331 { 332 struct timespec64 now; 333 u64 verf; 334 335 /* 336 * Because the time value is hashed, y2038 time_t overflow 337 * is irrelevant in this usage. 338 */ 339 ktime_get_raw_ts64(&now); 340 verf = siphash_2u64(now.tv_sec, now.tv_nsec, &nn->siphash_key); 341 memcpy(nn->writeverf, &verf, sizeof(nn->writeverf)); 342 } 343 344 /** 345 * nfsd_reset_write_verifier - Generate a new write verifier 346 * @nn: NFS net namespace 347 * 348 * This function updates the ->writeverf field of @nn. This field 349 * contains an opaque cookie that, according to Section 18.32.3 of 350 * RFC 8881, "the client can use to determine whether a server has 351 * changed instance state (e.g., server restart) between a call to 352 * WRITE and a subsequent call to either WRITE or COMMIT. This 353 * cookie MUST be unchanged during a single instance of the NFSv4.1 354 * server and MUST be unique between instances of the NFSv4.1 355 * server." 356 */ 357 void nfsd_reset_write_verifier(struct nfsd_net *nn) 358 { 359 write_seqlock(&nn->writeverf_lock); 360 nfsd_reset_write_verifier_locked(nn); 361 write_sequnlock(&nn->writeverf_lock); 362 } 363 364 /* 365 * Crank up a set of per-namespace resources for a new NFSD instance, 366 * including lockd, a duplicate reply cache, an open file cache 367 * instance, and a cache of NFSv4 state objects. 368 */ 369 static int nfsd_startup_net(struct net *net, const struct cred *cred) 370 { 371 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 372 int ret; 373 374 if (nn->nfsd_net_up) 375 return 0; 376 377 ret = nfsd_startup_generic(); 378 if (ret) 379 return ret; 380 ret = nfsd_init_socks(net, cred); 381 if (ret) 382 goto out_socks; 383 384 if (nfsd_needs_lockd(nn) && !nn->lockd_up) { 385 ret = lockd_up(net, cred); 386 if (ret) 387 goto out_socks; 388 nn->lockd_up = true; 389 } 390 391 ret = nfsd_file_cache_start_net(net); 392 if (ret) 393 goto out_lockd; 394 395 ret = nfsd_reply_cache_init(nn); 396 if (ret) 397 goto out_filecache; 398 399 #ifdef CONFIG_NFSD_V4_2_INTER_SSC 400 nfsd4_ssc_init_umount_work(nn); 401 #endif 402 ret = nfs4_state_start_net(net); 403 if (ret) 404 goto out_reply_cache; 405 406 nn->nfsd_net_up = true; 407 return 0; 408 409 out_reply_cache: 410 nfsd_reply_cache_shutdown(nn); 411 out_filecache: 412 nfsd_file_cache_shutdown_net(net); 413 out_lockd: 414 if (nn->lockd_up) { 415 lockd_down(net); 416 nn->lockd_up = false; 417 } 418 out_socks: 419 nfsd_shutdown_generic(); 420 return ret; 421 } 422 423 static void nfsd_shutdown_net(struct net *net) 424 { 425 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 426 427 if (!nn->nfsd_net_up) 428 return; 429 430 percpu_ref_kill_and_confirm(&nn->nfsd_net_ref, nfsd_net_done); 431 wait_for_completion(&nn->nfsd_net_confirm_done); 432 433 nfsd_export_flush(net); 434 nfs4_state_shutdown_net(net); 435 nfsd_reply_cache_shutdown(nn); 436 nfsd_file_cache_shutdown_net(net); 437 if (nn->lockd_up) { 438 lockd_down(net); 439 nn->lockd_up = false; 440 } 441 442 wait_for_completion(&nn->nfsd_net_free_done); 443 percpu_ref_exit(&nn->nfsd_net_ref); 444 445 nn->nfsd_net_up = false; 446 nfsd_shutdown_generic(); 447 } 448 449 static DEFINE_SPINLOCK(nfsd_notifier_lock); 450 static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event, 451 void *ptr) 452 { 453 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; 454 struct net_device *dev = ifa->ifa_dev->dev; 455 struct net *net = dev_net(dev); 456 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 457 struct sockaddr_in sin; 458 459 if (event != NETDEV_DOWN || !nn->nfsd_serv) 460 goto out; 461 462 spin_lock(&nfsd_notifier_lock); 463 if (nn->nfsd_serv) { 464 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local); 465 sin.sin_family = AF_INET; 466 sin.sin_addr.s_addr = ifa->ifa_local; 467 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin); 468 } 469 spin_unlock(&nfsd_notifier_lock); 470 471 out: 472 return NOTIFY_DONE; 473 } 474 475 static struct notifier_block nfsd_inetaddr_notifier = { 476 .notifier_call = nfsd_inetaddr_event, 477 }; 478 479 #if IS_ENABLED(CONFIG_IPV6) 480 static int nfsd_inet6addr_event(struct notifier_block *this, 481 unsigned long event, void *ptr) 482 { 483 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; 484 struct net_device *dev = ifa->idev->dev; 485 struct net *net = dev_net(dev); 486 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 487 struct sockaddr_in6 sin6; 488 489 if (event != NETDEV_DOWN || !nn->nfsd_serv) 490 goto out; 491 492 spin_lock(&nfsd_notifier_lock); 493 if (nn->nfsd_serv) { 494 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr); 495 sin6.sin6_family = AF_INET6; 496 sin6.sin6_addr = ifa->addr; 497 if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 498 sin6.sin6_scope_id = ifa->idev->dev->ifindex; 499 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6); 500 } 501 spin_unlock(&nfsd_notifier_lock); 502 503 out: 504 return NOTIFY_DONE; 505 } 506 507 static struct notifier_block nfsd_inet6addr_notifier = { 508 .notifier_call = nfsd_inet6addr_event, 509 }; 510 #endif 511 512 /* Only used under nfsd_mutex, so this atomic may be overkill: */ 513 static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0); 514 515 /** 516 * nfsd_destroy_serv - tear down NFSD's svc_serv for a namespace 517 * @net: network namespace the NFS service is associated with 518 */ 519 void nfsd_destroy_serv(struct net *net) 520 { 521 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 522 struct svc_serv *serv = nn->nfsd_serv; 523 524 lockdep_assert_held(&nfsd_mutex); 525 526 spin_lock(&nfsd_notifier_lock); 527 nn->nfsd_serv = NULL; 528 spin_unlock(&nfsd_notifier_lock); 529 530 /* check if the notifier still has clients */ 531 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) { 532 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier); 533 #if IS_ENABLED(CONFIG_IPV6) 534 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier); 535 #endif 536 } 537 538 /* 539 * write_ports can create the server without actually starting 540 * any threads. If we get shut down before any threads are 541 * started, then nfsd_destroy_serv will be run before any of this 542 * other initialization has been done except the rpcb information. 543 */ 544 svc_xprt_destroy_all(serv, net, true); 545 nfsd_shutdown_net(net); 546 svc_destroy(&serv); 547 } 548 549 void nfsd_reset_versions(struct nfsd_net *nn) 550 { 551 int i; 552 553 for (i = 0; i <= NFSD_MAXVERS; i++) 554 if (nfsd_vers(nn, i, NFSD_TEST)) 555 return; 556 557 for (i = 0; i <= NFSD_MAXVERS; i++) 558 if (i != 4) 559 nfsd_vers(nn, i, NFSD_SET); 560 else { 561 int minor = 0; 562 while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0) 563 minor++; 564 } 565 } 566 567 static int nfsd_get_default_max_blksize(void) 568 { 569 struct sysinfo i; 570 unsigned long long target; 571 unsigned long ret; 572 573 si_meminfo(&i); 574 target = (i.totalram - i.totalhigh) << PAGE_SHIFT; 575 /* 576 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig 577 * machines, but only uses 32K on 128M machines. Bottom out at 578 * 8K on 32M and smaller. Of course, this is only a default. 579 */ 580 target >>= 12; 581 582 ret = NFSSVC_DEFBLKSIZE; 583 while (ret > target && ret >= 8*1024*2) 584 ret /= 2; 585 return ret; 586 } 587 588 void nfsd_shutdown_threads(struct net *net) 589 { 590 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 591 struct svc_serv *serv; 592 593 mutex_lock(&nfsd_mutex); 594 serv = nn->nfsd_serv; 595 if (serv == NULL) { 596 mutex_unlock(&nfsd_mutex); 597 return; 598 } 599 600 /* Kill outstanding nfsd threads */ 601 svc_set_num_threads(serv, NULL, 0); 602 nfsd_destroy_serv(net); 603 mutex_unlock(&nfsd_mutex); 604 } 605 606 struct svc_rqst *nfsd_current_rqst(void) 607 { 608 if (kthread_func(current) == nfsd) 609 return kthread_data(current); 610 return NULL; 611 } 612 613 int nfsd_create_serv(struct net *net) 614 { 615 int error; 616 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 617 struct svc_serv *serv; 618 619 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 620 if (nn->nfsd_serv) 621 return 0; 622 623 error = percpu_ref_init(&nn->nfsd_net_ref, nfsd_net_free, 624 0, GFP_KERNEL); 625 if (error) 626 return error; 627 init_completion(&nn->nfsd_net_free_done); 628 init_completion(&nn->nfsd_net_confirm_done); 629 630 if (nfsd_max_blksize == 0) 631 nfsd_max_blksize = nfsd_get_default_max_blksize(); 632 nfsd_reset_versions(nn); 633 serv = svc_create_pooled(nfsd_programs, ARRAY_SIZE(nfsd_programs), 634 &nn->nfsd_svcstats, 635 nfsd_max_blksize, nfsd); 636 if (serv == NULL) 637 return -ENOMEM; 638 639 error = svc_bind(serv, net); 640 if (error < 0) { 641 svc_destroy(&serv); 642 return error; 643 } 644 spin_lock(&nfsd_notifier_lock); 645 nn->nfsd_serv = serv; 646 spin_unlock(&nfsd_notifier_lock); 647 648 /* check if the notifier is already set */ 649 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) { 650 register_inetaddr_notifier(&nfsd_inetaddr_notifier); 651 #if IS_ENABLED(CONFIG_IPV6) 652 register_inet6addr_notifier(&nfsd_inet6addr_notifier); 653 #endif 654 } 655 nfsd_reset_write_verifier(nn); 656 return 0; 657 } 658 659 int nfsd_nrpools(struct net *net) 660 { 661 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 662 663 if (nn->nfsd_serv == NULL) 664 return 0; 665 else 666 return nn->nfsd_serv->sv_nrpools; 667 } 668 669 int nfsd_get_nrthreads(int n, int *nthreads, struct net *net) 670 { 671 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 672 struct svc_serv *serv = nn->nfsd_serv; 673 int i; 674 675 if (serv) 676 for (i = 0; i < serv->sv_nrpools && i < n; i++) 677 nthreads[i] = serv->sv_pools[i].sp_nrthreads; 678 return 0; 679 } 680 681 /** 682 * nfsd_set_nrthreads - set the number of running threads in the net's service 683 * @n: number of array members in @nthreads 684 * @nthreads: array of thread counts for each pool 685 * @net: network namespace to operate within 686 * 687 * This function alters the number of running threads for the given network 688 * namespace in each pool. If passed an array longer then the number of pools 689 * the extra pool settings are ignored. If passed an array shorter than the 690 * number of pools, the missing values are interpreted as 0's. 691 * 692 * Returns 0 on success or a negative errno on error. 693 */ 694 int nfsd_set_nrthreads(int n, int *nthreads, struct net *net) 695 { 696 int i = 0; 697 int tot = 0; 698 int err = 0; 699 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 700 701 lockdep_assert_held(&nfsd_mutex); 702 703 if (nn->nfsd_serv == NULL || n <= 0) 704 return 0; 705 706 /* 707 * Special case: When n == 1, pass in NULL for the pool, so that the 708 * change is distributed equally among them. 709 */ 710 if (n == 1) 711 return svc_set_num_threads(nn->nfsd_serv, NULL, nthreads[0]); 712 713 if (n > nn->nfsd_serv->sv_nrpools) 714 n = nn->nfsd_serv->sv_nrpools; 715 716 /* enforce a global maximum number of threads */ 717 tot = 0; 718 for (i = 0; i < n; i++) { 719 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS); 720 tot += nthreads[i]; 721 } 722 if (tot > NFSD_MAXSERVS) { 723 /* total too large: scale down requested numbers */ 724 for (i = 0; i < n && tot > 0; i++) { 725 int new = nthreads[i] * NFSD_MAXSERVS / tot; 726 tot -= (nthreads[i] - new); 727 nthreads[i] = new; 728 } 729 for (i = 0; i < n && tot > 0; i++) { 730 nthreads[i]--; 731 tot--; 732 } 733 } 734 735 /* apply the new numbers */ 736 for (i = 0; i < n; i++) { 737 err = svc_set_num_threads(nn->nfsd_serv, 738 &nn->nfsd_serv->sv_pools[i], 739 nthreads[i]); 740 if (err) 741 goto out; 742 } 743 744 /* Anything undefined in array is considered to be 0 */ 745 for (i = n; i < nn->nfsd_serv->sv_nrpools; ++i) { 746 err = svc_set_num_threads(nn->nfsd_serv, 747 &nn->nfsd_serv->sv_pools[i], 748 0); 749 if (err) 750 goto out; 751 } 752 out: 753 return err; 754 } 755 756 /** 757 * nfsd_svc: start up or shut down the nfsd server 758 * @n: number of array members in @nthreads 759 * @nthreads: array of thread counts for each pool 760 * @net: network namespace to operate within 761 * @cred: credentials to use for xprt creation 762 * @scope: server scope value (defaults to nodename) 763 * 764 * Adjust the number of threads in each pool and return the new 765 * total number of threads in the service. 766 */ 767 int 768 nfsd_svc(int n, int *nthreads, struct net *net, const struct cred *cred, const char *scope) 769 { 770 int error; 771 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 772 struct svc_serv *serv; 773 774 lockdep_assert_held(&nfsd_mutex); 775 776 dprintk("nfsd: creating service\n"); 777 778 strscpy(nn->nfsd_name, scope ? scope : utsname()->nodename, 779 sizeof(nn->nfsd_name)); 780 781 error = nfsd_create_serv(net); 782 if (error) 783 goto out; 784 serv = nn->nfsd_serv; 785 786 error = nfsd_startup_net(net, cred); 787 if (error) 788 goto out_put; 789 error = nfsd_set_nrthreads(n, nthreads, net); 790 if (error) 791 goto out_put; 792 error = serv->sv_nrthreads; 793 out_put: 794 if (serv->sv_nrthreads == 0) 795 nfsd_destroy_serv(net); 796 out: 797 return error; 798 } 799 800 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 801 static bool 802 nfsd_support_acl_version(int vers) 803 { 804 if (vers >= NFSD_ACL_MINVERS && vers < NFSD_ACL_NRVERS) 805 return nfsd_acl_version[vers] != NULL; 806 return false; 807 } 808 809 static int 810 nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp, 811 u32 version, int family, unsigned short proto, 812 unsigned short port) 813 { 814 if (!nfsd_support_acl_version(version) || 815 !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST)) 816 return 0; 817 return svc_generic_rpcbind_set(net, progp, version, family, 818 proto, port); 819 } 820 821 static __be32 822 nfsd_acl_init_request(struct svc_rqst *rqstp, 823 const struct svc_program *progp, 824 struct svc_process_info *ret) 825 { 826 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); 827 int i; 828 829 if (likely(nfsd_support_acl_version(rqstp->rq_vers) && 830 nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST))) 831 return svc_generic_init_request(rqstp, progp, ret); 832 833 ret->mismatch.lovers = NFSD_ACL_NRVERS; 834 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) { 835 if (nfsd_support_acl_version(rqstp->rq_vers) && 836 nfsd_vers(nn, i, NFSD_TEST)) { 837 ret->mismatch.lovers = i; 838 break; 839 } 840 } 841 if (ret->mismatch.lovers == NFSD_ACL_NRVERS) 842 return rpc_prog_unavail; 843 ret->mismatch.hivers = NFSD_ACL_MINVERS; 844 for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) { 845 if (nfsd_support_acl_version(rqstp->rq_vers) && 846 nfsd_vers(nn, i, NFSD_TEST)) { 847 ret->mismatch.hivers = i; 848 break; 849 } 850 } 851 return rpc_prog_mismatch; 852 } 853 #endif 854 855 static int 856 nfsd_rpcbind_set(struct net *net, const struct svc_program *progp, 857 u32 version, int family, unsigned short proto, 858 unsigned short port) 859 { 860 if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST)) 861 return 0; 862 return svc_generic_rpcbind_set(net, progp, version, family, 863 proto, port); 864 } 865 866 static __be32 867 nfsd_init_request(struct svc_rqst *rqstp, 868 const struct svc_program *progp, 869 struct svc_process_info *ret) 870 { 871 struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); 872 int i; 873 874 if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST))) 875 return svc_generic_init_request(rqstp, progp, ret); 876 877 ret->mismatch.lovers = NFSD_MAXVERS + 1; 878 for (i = NFSD_MINVERS; i <= NFSD_MAXVERS; i++) { 879 if (nfsd_vers(nn, i, NFSD_TEST)) { 880 ret->mismatch.lovers = i; 881 break; 882 } 883 } 884 if (ret->mismatch.lovers > NFSD_MAXVERS) 885 return rpc_prog_unavail; 886 ret->mismatch.hivers = NFSD_MINVERS; 887 for (i = NFSD_MAXVERS; i >= NFSD_MINVERS; i--) { 888 if (nfsd_vers(nn, i, NFSD_TEST)) { 889 ret->mismatch.hivers = i; 890 break; 891 } 892 } 893 return rpc_prog_mismatch; 894 } 895 896 /* 897 * This is the NFS server kernel thread 898 */ 899 static int 900 nfsd(void *vrqstp) 901 { 902 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; 903 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list); 904 struct net *net = perm_sock->xpt_net; 905 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 906 907 /* At this point, the thread shares current->fs 908 * with the init process. We need to create files with the 909 * umask as defined by the client instead of init's umask. 910 */ 911 svc_thread_init_status(rqstp, unshare_fs_struct()); 912 913 current->fs->umask = 0; 914 915 atomic_inc(&nfsd_th_cnt); 916 917 set_freezable(); 918 919 /* 920 * The main request loop 921 */ 922 while (!svc_thread_should_stop(rqstp)) { 923 svc_recv(rqstp); 924 nfsd_file_net_dispose(nn); 925 } 926 927 atomic_dec(&nfsd_th_cnt); 928 929 /* Release the thread */ 930 svc_exit_thread(rqstp); 931 return 0; 932 } 933 934 /** 935 * nfsd_dispatch - Process an NFS or NFSACL or LOCALIO Request 936 * @rqstp: incoming request 937 * 938 * This RPC dispatcher integrates the NFS server's duplicate reply cache. 939 * 940 * Return values: 941 * %0: Processing complete; do not send a Reply 942 * %1: Processing complete; send Reply in rqstp->rq_res 943 */ 944 int nfsd_dispatch(struct svc_rqst *rqstp) 945 { 946 const struct svc_procedure *proc = rqstp->rq_procinfo; 947 __be32 *statp = rqstp->rq_accept_statp; 948 struct nfsd_cacherep *rp; 949 unsigned int start, len; 950 __be32 *nfs_reply; 951 952 /* 953 * Give the xdr decoder a chance to change this if it wants 954 * (necessary in the NFSv4.0 compound case) 955 */ 956 rqstp->rq_cachetype = proc->pc_cachetype; 957 958 /* 959 * ->pc_decode advances the argument stream past the NFS 960 * Call header, so grab the header's starting location and 961 * size now for the call to nfsd_cache_lookup(). 962 */ 963 start = xdr_stream_pos(&rqstp->rq_arg_stream); 964 len = xdr_stream_remaining(&rqstp->rq_arg_stream); 965 if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream)) 966 goto out_decode_err; 967 968 /* 969 * Release rq_status_counter setting it to an odd value after the rpc 970 * request has been properly parsed. rq_status_counter is used to 971 * notify the consumers if the rqstp fields are stable 972 * (rq_status_counter is odd) or not meaningful (rq_status_counter 973 * is even). 974 */ 975 smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter | 1); 976 977 rp = NULL; 978 switch (nfsd_cache_lookup(rqstp, start, len, &rp)) { 979 case RC_DOIT: 980 break; 981 case RC_REPLY: 982 goto out_cached_reply; 983 case RC_DROPIT: 984 goto out_dropit; 985 } 986 987 nfs_reply = xdr_inline_decode(&rqstp->rq_res_stream, 0); 988 *statp = proc->pc_func(rqstp); 989 if (test_bit(RQ_DROPME, &rqstp->rq_flags)) 990 goto out_update_drop; 991 992 if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream)) 993 goto out_encode_err; 994 995 /* 996 * Release rq_status_counter setting it to an even value after the rpc 997 * request has been properly processed. 998 */ 999 smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter + 1); 1000 1001 nfsd_cache_update(rqstp, rp, rqstp->rq_cachetype, nfs_reply); 1002 out_cached_reply: 1003 return 1; 1004 1005 out_decode_err: 1006 trace_nfsd_garbage_args_err(rqstp); 1007 *statp = rpc_garbage_args; 1008 return 1; 1009 1010 out_update_drop: 1011 nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); 1012 out_dropit: 1013 return 0; 1014 1015 out_encode_err: 1016 trace_nfsd_cant_encode_err(rqstp); 1017 nfsd_cache_update(rqstp, rp, RC_NOCACHE, NULL); 1018 *statp = rpc_system_err; 1019 return 1; 1020 } 1021 1022 /** 1023 * nfssvc_decode_voidarg - Decode void arguments 1024 * @rqstp: Server RPC transaction context 1025 * @xdr: XDR stream positioned at arguments to decode 1026 * 1027 * Return values: 1028 * %false: Arguments were not valid 1029 * %true: Decoding was successful 1030 */ 1031 bool nfssvc_decode_voidarg(struct svc_rqst *rqstp, struct xdr_stream *xdr) 1032 { 1033 return true; 1034 } 1035 1036 /** 1037 * nfssvc_encode_voidres - Encode void results 1038 * @rqstp: Server RPC transaction context 1039 * @xdr: XDR stream into which to encode results 1040 * 1041 * Return values: 1042 * %false: Local error while encoding 1043 * %true: Encoding was successful 1044 */ 1045 bool nfssvc_encode_voidres(struct svc_rqst *rqstp, struct xdr_stream *xdr) 1046 { 1047 return true; 1048 } 1049