1 /* 2 * Central processing for nfsd. 3 * 4 * Authors: Olaf Kirch (okir@monad.swb.de) 5 * 6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> 7 */ 8 9 #include <linux/sched.h> 10 #include <linux/freezer.h> 11 #include <linux/module.h> 12 #include <linux/fs_struct.h> 13 #include <linux/swap.h> 14 15 #include <linux/sunrpc/stats.h> 16 #include <linux/sunrpc/svcsock.h> 17 #include <linux/sunrpc/svc_xprt.h> 18 #include <linux/lockd/bind.h> 19 #include <linux/nfsacl.h> 20 #include <linux/seq_file.h> 21 #include <linux/inetdevice.h> 22 #include <net/addrconf.h> 23 #include <net/ipv6.h> 24 #include <net/net_namespace.h> 25 #include "nfsd.h" 26 #include "cache.h" 27 #include "vfs.h" 28 #include "netns.h" 29 30 #define NFSDDBG_FACILITY NFSDDBG_SVC 31 32 extern struct svc_program nfsd_program; 33 static int nfsd(void *vrqstp); 34 35 /* 36 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members 37 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some 38 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt 39 * 40 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a 41 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number 42 * of nfsd threads must exist and each must listed in ->sp_all_threads in each 43 * entry of ->sv_pools[]. 44 * 45 * Transitions of the thread count between zero and non-zero are of particular 46 * interest since the svc_serv needs to be created and initialized at that 47 * point, or freed. 48 * 49 * Finally, the nfsd_mutex also protects some of the global variables that are 50 * accessed when nfsd starts and that are settable via the write_* routines in 51 * nfsctl.c. In particular: 52 * 53 * user_recovery_dirname 54 * user_lease_time 55 * nfsd_versions 56 */ 57 DEFINE_MUTEX(nfsd_mutex); 58 59 /* 60 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used. 61 * nfsd_drc_max_pages limits the total amount of memory available for 62 * version 4.1 DRC caches. 63 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage. 64 */ 65 spinlock_t nfsd_drc_lock; 66 unsigned long nfsd_drc_max_mem; 67 unsigned long nfsd_drc_mem_used; 68 69 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 70 static struct svc_stat nfsd_acl_svcstats; 71 static struct svc_version * nfsd_acl_version[] = { 72 [2] = &nfsd_acl_version2, 73 [3] = &nfsd_acl_version3, 74 }; 75 76 #define NFSD_ACL_MINVERS 2 77 #define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) 78 static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS]; 79 80 static struct svc_program nfsd_acl_program = { 81 .pg_prog = NFS_ACL_PROGRAM, 82 .pg_nvers = NFSD_ACL_NRVERS, 83 .pg_vers = nfsd_acl_versions, 84 .pg_name = "nfsacl", 85 .pg_class = "nfsd", 86 .pg_stats = &nfsd_acl_svcstats, 87 .pg_authenticate = &svc_set_client, 88 }; 89 90 static struct svc_stat nfsd_acl_svcstats = { 91 .program = &nfsd_acl_program, 92 }; 93 #endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ 94 95 static struct svc_version * nfsd_version[] = { 96 [2] = &nfsd_version2, 97 #if defined(CONFIG_NFSD_V3) 98 [3] = &nfsd_version3, 99 #endif 100 #if defined(CONFIG_NFSD_V4) 101 [4] = &nfsd_version4, 102 #endif 103 }; 104 105 #define NFSD_MINVERS 2 106 #define NFSD_NRVERS ARRAY_SIZE(nfsd_version) 107 static struct svc_version *nfsd_versions[NFSD_NRVERS]; 108 109 struct svc_program nfsd_program = { 110 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 111 .pg_next = &nfsd_acl_program, 112 #endif 113 .pg_prog = NFS_PROGRAM, /* program number */ 114 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */ 115 .pg_vers = nfsd_versions, /* version table */ 116 .pg_name = "nfsd", /* program name */ 117 .pg_class = "nfsd", /* authentication class */ 118 .pg_stats = &nfsd_svcstats, /* version table */ 119 .pg_authenticate = &svc_set_client, /* export authentication */ 120 121 }; 122 123 static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = { 124 [0] = 1, 125 [1] = 1, 126 [2] = 1, 127 }; 128 129 int nfsd_vers(int vers, enum vers_op change) 130 { 131 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS) 132 return 0; 133 switch(change) { 134 case NFSD_SET: 135 nfsd_versions[vers] = nfsd_version[vers]; 136 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 137 if (vers < NFSD_ACL_NRVERS) 138 nfsd_acl_versions[vers] = nfsd_acl_version[vers]; 139 #endif 140 break; 141 case NFSD_CLEAR: 142 nfsd_versions[vers] = NULL; 143 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 144 if (vers < NFSD_ACL_NRVERS) 145 nfsd_acl_versions[vers] = NULL; 146 #endif 147 break; 148 case NFSD_TEST: 149 return nfsd_versions[vers] != NULL; 150 case NFSD_AVAIL: 151 return nfsd_version[vers] != NULL; 152 } 153 return 0; 154 } 155 156 int nfsd_minorversion(u32 minorversion, enum vers_op change) 157 { 158 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION) 159 return -1; 160 switch(change) { 161 case NFSD_SET: 162 nfsd_supported_minorversions[minorversion] = true; 163 break; 164 case NFSD_CLEAR: 165 nfsd_supported_minorversions[minorversion] = false; 166 break; 167 case NFSD_TEST: 168 return nfsd_supported_minorversions[minorversion]; 169 case NFSD_AVAIL: 170 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION; 171 } 172 return 0; 173 } 174 175 /* 176 * Maximum number of nfsd processes 177 */ 178 #define NFSD_MAXSERVS 8192 179 180 int nfsd_nrthreads(struct net *net) 181 { 182 int rv = 0; 183 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 184 185 mutex_lock(&nfsd_mutex); 186 if (nn->nfsd_serv) 187 rv = nn->nfsd_serv->sv_nrthreads; 188 mutex_unlock(&nfsd_mutex); 189 return rv; 190 } 191 192 static int nfsd_init_socks(struct net *net) 193 { 194 int error; 195 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 196 197 if (!list_empty(&nn->nfsd_serv->sv_permsocks)) 198 return 0; 199 200 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT, 201 SVC_SOCK_DEFAULTS); 202 if (error < 0) 203 return error; 204 205 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT, 206 SVC_SOCK_DEFAULTS); 207 if (error < 0) 208 return error; 209 210 return 0; 211 } 212 213 static int nfsd_users = 0; 214 215 static int nfsd_startup_generic(int nrservs) 216 { 217 int ret; 218 219 if (nfsd_users++) 220 return 0; 221 222 /* 223 * Readahead param cache - will no-op if it already exists. 224 * (Note therefore results will be suboptimal if number of 225 * threads is modified after nfsd start.) 226 */ 227 ret = nfsd_racache_init(2*nrservs); 228 if (ret) 229 goto dec_users; 230 231 ret = nfs4_state_start(); 232 if (ret) 233 goto out_racache; 234 return 0; 235 236 out_racache: 237 nfsd_racache_shutdown(); 238 dec_users: 239 nfsd_users--; 240 return ret; 241 } 242 243 static void nfsd_shutdown_generic(void) 244 { 245 if (--nfsd_users) 246 return; 247 248 nfs4_state_shutdown(); 249 nfsd_racache_shutdown(); 250 } 251 252 static bool nfsd_needs_lockd(void) 253 { 254 #if defined(CONFIG_NFSD_V3) 255 return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL); 256 #else 257 return (nfsd_versions[2] != NULL); 258 #endif 259 } 260 261 static int nfsd_startup_net(int nrservs, struct net *net) 262 { 263 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 264 int ret; 265 266 if (nn->nfsd_net_up) 267 return 0; 268 269 ret = nfsd_startup_generic(nrservs); 270 if (ret) 271 return ret; 272 ret = nfsd_init_socks(net); 273 if (ret) 274 goto out_socks; 275 276 if (nfsd_needs_lockd() && !nn->lockd_up) { 277 ret = lockd_up(net); 278 if (ret) 279 goto out_socks; 280 nn->lockd_up = 1; 281 } 282 283 ret = nfs4_state_start_net(net); 284 if (ret) 285 goto out_lockd; 286 287 nn->nfsd_net_up = true; 288 return 0; 289 290 out_lockd: 291 if (nn->lockd_up) { 292 lockd_down(net); 293 nn->lockd_up = 0; 294 } 295 out_socks: 296 nfsd_shutdown_generic(); 297 return ret; 298 } 299 300 static void nfsd_shutdown_net(struct net *net) 301 { 302 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 303 304 nfs4_state_shutdown_net(net); 305 if (nn->lockd_up) { 306 lockd_down(net); 307 nn->lockd_up = 0; 308 } 309 nn->nfsd_net_up = false; 310 nfsd_shutdown_generic(); 311 } 312 313 static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event, 314 void *ptr) 315 { 316 struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; 317 struct net_device *dev = ifa->ifa_dev->dev; 318 struct net *net = dev_net(dev); 319 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 320 struct sockaddr_in sin; 321 322 if (event != NETDEV_DOWN) 323 goto out; 324 325 if (nn->nfsd_serv) { 326 dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local); 327 sin.sin_family = AF_INET; 328 sin.sin_addr.s_addr = ifa->ifa_local; 329 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin); 330 } 331 332 out: 333 return NOTIFY_DONE; 334 } 335 336 static struct notifier_block nfsd_inetaddr_notifier = { 337 .notifier_call = nfsd_inetaddr_event, 338 }; 339 340 #if IS_ENABLED(CONFIG_IPV6) 341 static int nfsd_inet6addr_event(struct notifier_block *this, 342 unsigned long event, void *ptr) 343 { 344 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; 345 struct net_device *dev = ifa->idev->dev; 346 struct net *net = dev_net(dev); 347 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 348 struct sockaddr_in6 sin6; 349 350 if (event != NETDEV_DOWN) 351 goto out; 352 353 if (nn->nfsd_serv) { 354 dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr); 355 sin6.sin6_family = AF_INET6; 356 sin6.sin6_addr = ifa->addr; 357 svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6); 358 } 359 360 out: 361 return NOTIFY_DONE; 362 } 363 364 static struct notifier_block nfsd_inet6addr_notifier = { 365 .notifier_call = nfsd_inet6addr_event, 366 }; 367 #endif 368 369 static void nfsd_last_thread(struct svc_serv *serv, struct net *net) 370 { 371 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 372 373 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier); 374 #if IS_ENABLED(CONFIG_IPV6) 375 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier); 376 #endif 377 /* 378 * write_ports can create the server without actually starting 379 * any threads--if we get shut down before any threads are 380 * started, then nfsd_last_thread will be run before any of this 381 * other initialization has been done except the rpcb information. 382 */ 383 svc_rpcb_cleanup(serv, net); 384 if (!nn->nfsd_net_up) 385 return; 386 387 nfsd_shutdown_net(net); 388 printk(KERN_WARNING "nfsd: last server has exited, flushing export " 389 "cache\n"); 390 nfsd_export_flush(net); 391 } 392 393 void nfsd_reset_versions(void) 394 { 395 int found_one = 0; 396 int i; 397 398 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { 399 if (nfsd_program.pg_vers[i]) 400 found_one = 1; 401 } 402 403 if (!found_one) { 404 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) 405 nfsd_program.pg_vers[i] = nfsd_version[i]; 406 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 407 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) 408 nfsd_acl_program.pg_vers[i] = 409 nfsd_acl_version[i]; 410 #endif 411 } 412 } 413 414 /* 415 * Each session guarantees a negotiated per slot memory cache for replies 416 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated 417 * NFSv4.1 server might want to use more memory for a DRC than a machine 418 * with mutiple services. 419 * 420 * Impose a hard limit on the number of pages for the DRC which varies 421 * according to the machines free pages. This is of course only a default. 422 * 423 * For now this is a #defined shift which could be under admin control 424 * in the future. 425 */ 426 static void set_max_drc(void) 427 { 428 #define NFSD_DRC_SIZE_SHIFT 10 429 nfsd_drc_max_mem = (nr_free_buffer_pages() 430 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE; 431 nfsd_drc_mem_used = 0; 432 spin_lock_init(&nfsd_drc_lock); 433 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem); 434 } 435 436 static int nfsd_get_default_max_blksize(void) 437 { 438 struct sysinfo i; 439 unsigned long long target; 440 unsigned long ret; 441 442 si_meminfo(&i); 443 target = (i.totalram - i.totalhigh) << PAGE_SHIFT; 444 /* 445 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig 446 * machines, but only uses 32K on 128M machines. Bottom out at 447 * 8K on 32M and smaller. Of course, this is only a default. 448 */ 449 target >>= 12; 450 451 ret = NFSSVC_MAXBLKSIZE; 452 while (ret > target && ret >= 8*1024*2) 453 ret /= 2; 454 return ret; 455 } 456 457 static struct svc_serv_ops nfsd_thread_sv_ops = { 458 .svo_shutdown = nfsd_last_thread, 459 .svo_function = nfsd, 460 .svo_enqueue_xprt = svc_xprt_do_enqueue, 461 .svo_setup = svc_set_num_threads, 462 .svo_module = THIS_MODULE, 463 }; 464 465 int nfsd_create_serv(struct net *net) 466 { 467 int error; 468 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 469 470 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 471 if (nn->nfsd_serv) { 472 svc_get(nn->nfsd_serv); 473 return 0; 474 } 475 if (nfsd_max_blksize == 0) 476 nfsd_max_blksize = nfsd_get_default_max_blksize(); 477 nfsd_reset_versions(); 478 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize, 479 &nfsd_thread_sv_ops); 480 if (nn->nfsd_serv == NULL) 481 return -ENOMEM; 482 483 nn->nfsd_serv->sv_maxconn = nn->max_connections; 484 error = svc_bind(nn->nfsd_serv, net); 485 if (error < 0) { 486 svc_destroy(nn->nfsd_serv); 487 return error; 488 } 489 490 set_max_drc(); 491 register_inetaddr_notifier(&nfsd_inetaddr_notifier); 492 #if IS_ENABLED(CONFIG_IPV6) 493 register_inet6addr_notifier(&nfsd_inet6addr_notifier); 494 #endif 495 do_gettimeofday(&nn->nfssvc_boot); /* record boot time */ 496 return 0; 497 } 498 499 int nfsd_nrpools(struct net *net) 500 { 501 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 502 503 if (nn->nfsd_serv == NULL) 504 return 0; 505 else 506 return nn->nfsd_serv->sv_nrpools; 507 } 508 509 int nfsd_get_nrthreads(int n, int *nthreads, struct net *net) 510 { 511 int i = 0; 512 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 513 514 if (nn->nfsd_serv != NULL) { 515 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++) 516 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads; 517 } 518 519 return 0; 520 } 521 522 void nfsd_destroy(struct net *net) 523 { 524 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 525 int destroy = (nn->nfsd_serv->sv_nrthreads == 1); 526 527 if (destroy) 528 svc_shutdown_net(nn->nfsd_serv, net); 529 svc_destroy(nn->nfsd_serv); 530 if (destroy) 531 nn->nfsd_serv = NULL; 532 } 533 534 int nfsd_set_nrthreads(int n, int *nthreads, struct net *net) 535 { 536 int i = 0; 537 int tot = 0; 538 int err = 0; 539 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 540 541 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 542 543 if (nn->nfsd_serv == NULL || n <= 0) 544 return 0; 545 546 if (n > nn->nfsd_serv->sv_nrpools) 547 n = nn->nfsd_serv->sv_nrpools; 548 549 /* enforce a global maximum number of threads */ 550 tot = 0; 551 for (i = 0; i < n; i++) { 552 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS); 553 tot += nthreads[i]; 554 } 555 if (tot > NFSD_MAXSERVS) { 556 /* total too large: scale down requested numbers */ 557 for (i = 0; i < n && tot > 0; i++) { 558 int new = nthreads[i] * NFSD_MAXSERVS / tot; 559 tot -= (nthreads[i] - new); 560 nthreads[i] = new; 561 } 562 for (i = 0; i < n && tot > 0; i++) { 563 nthreads[i]--; 564 tot--; 565 } 566 } 567 568 /* 569 * There must always be a thread in pool 0; the admin 570 * can't shut down NFS completely using pool_threads. 571 */ 572 if (nthreads[0] == 0) 573 nthreads[0] = 1; 574 575 /* apply the new numbers */ 576 svc_get(nn->nfsd_serv); 577 for (i = 0; i < n; i++) { 578 err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv, 579 &nn->nfsd_serv->sv_pools[i], nthreads[i]); 580 if (err) 581 break; 582 } 583 nfsd_destroy(net); 584 return err; 585 } 586 587 /* 588 * Adjust the number of threads and return the new number of threads. 589 * This is also the function that starts the server if necessary, if 590 * this is the first time nrservs is nonzero. 591 */ 592 int 593 nfsd_svc(int nrservs, struct net *net) 594 { 595 int error; 596 bool nfsd_up_before; 597 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 598 599 mutex_lock(&nfsd_mutex); 600 dprintk("nfsd: creating service\n"); 601 602 nrservs = max(nrservs, 0); 603 nrservs = min(nrservs, NFSD_MAXSERVS); 604 error = 0; 605 606 if (nrservs == 0 && nn->nfsd_serv == NULL) 607 goto out; 608 609 error = nfsd_create_serv(net); 610 if (error) 611 goto out; 612 613 nfsd_up_before = nn->nfsd_net_up; 614 615 error = nfsd_startup_net(nrservs, net); 616 if (error) 617 goto out_destroy; 618 error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv, 619 NULL, nrservs); 620 if (error) 621 goto out_shutdown; 622 /* We are holding a reference to nn->nfsd_serv which 623 * we don't want to count in the return value, 624 * so subtract 1 625 */ 626 error = nn->nfsd_serv->sv_nrthreads - 1; 627 out_shutdown: 628 if (error < 0 && !nfsd_up_before) 629 nfsd_shutdown_net(net); 630 out_destroy: 631 nfsd_destroy(net); /* Release server */ 632 out: 633 mutex_unlock(&nfsd_mutex); 634 return error; 635 } 636 637 638 /* 639 * This is the NFS server kernel thread 640 */ 641 static int 642 nfsd(void *vrqstp) 643 { 644 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; 645 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list); 646 struct net *net = perm_sock->xpt_net; 647 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 648 int err; 649 650 /* Lock module and set up kernel thread */ 651 mutex_lock(&nfsd_mutex); 652 653 /* At this point, the thread shares current->fs 654 * with the init process. We need to create files with a 655 * umask of 0 instead of init's umask. */ 656 if (unshare_fs_struct() < 0) { 657 printk("Unable to start nfsd thread: out of memory\n"); 658 goto out; 659 } 660 661 current->fs->umask = 0; 662 663 /* 664 * thread is spawned with all signals set to SIG_IGN, re-enable 665 * the ones that will bring down the thread 666 */ 667 allow_signal(SIGKILL); 668 allow_signal(SIGHUP); 669 allow_signal(SIGINT); 670 allow_signal(SIGQUIT); 671 672 nfsdstats.th_cnt++; 673 mutex_unlock(&nfsd_mutex); 674 675 set_freezable(); 676 677 /* 678 * The main request loop 679 */ 680 for (;;) { 681 /* Update sv_maxconn if it has changed */ 682 rqstp->rq_server->sv_maxconn = nn->max_connections; 683 684 /* 685 * Find a socket with data available and call its 686 * recvfrom routine. 687 */ 688 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN) 689 ; 690 if (err == -EINTR) 691 break; 692 validate_process_creds(); 693 svc_process(rqstp); 694 validate_process_creds(); 695 } 696 697 /* Clear signals before calling svc_exit_thread() */ 698 flush_signals(current); 699 700 mutex_lock(&nfsd_mutex); 701 nfsdstats.th_cnt --; 702 703 out: 704 rqstp->rq_server = NULL; 705 706 /* Release the thread */ 707 svc_exit_thread(rqstp); 708 709 nfsd_destroy(net); 710 711 /* Release module */ 712 mutex_unlock(&nfsd_mutex); 713 module_put_and_exit(0); 714 return 0; 715 } 716 717 static __be32 map_new_errors(u32 vers, __be32 nfserr) 718 { 719 if (nfserr == nfserr_jukebox && vers == 2) 720 return nfserr_dropit; 721 if (nfserr == nfserr_wrongsec && vers < 4) 722 return nfserr_acces; 723 return nfserr; 724 } 725 726 int 727 nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) 728 { 729 struct svc_procedure *proc; 730 kxdrproc_t xdr; 731 __be32 nfserr; 732 __be32 *nfserrp; 733 734 dprintk("nfsd_dispatch: vers %d proc %d\n", 735 rqstp->rq_vers, rqstp->rq_proc); 736 proc = rqstp->rq_procinfo; 737 738 /* 739 * Give the xdr decoder a chance to change this if it wants 740 * (necessary in the NFSv4.0 compound case) 741 */ 742 rqstp->rq_cachetype = proc->pc_cachetype; 743 /* Decode arguments */ 744 xdr = proc->pc_decode; 745 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base, 746 rqstp->rq_argp)) { 747 dprintk("nfsd: failed to decode arguments!\n"); 748 *statp = rpc_garbage_args; 749 return 1; 750 } 751 752 /* Check whether we have this call in the cache. */ 753 switch (nfsd_cache_lookup(rqstp)) { 754 case RC_DROPIT: 755 return 0; 756 case RC_REPLY: 757 return 1; 758 case RC_DOIT:; 759 /* do it */ 760 } 761 762 /* need to grab the location to store the status, as 763 * nfsv4 does some encoding while processing 764 */ 765 nfserrp = rqstp->rq_res.head[0].iov_base 766 + rqstp->rq_res.head[0].iov_len; 767 rqstp->rq_res.head[0].iov_len += sizeof(__be32); 768 769 /* Now call the procedure handler, and encode NFS status. */ 770 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); 771 nfserr = map_new_errors(rqstp->rq_vers, nfserr); 772 if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) { 773 dprintk("nfsd: Dropping request; may be revisited later\n"); 774 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 775 return 0; 776 } 777 778 if (rqstp->rq_proc != 0) 779 *nfserrp++ = nfserr; 780 781 /* Encode result. 782 * For NFSv2, additional info is never returned in case of an error. 783 */ 784 if (!(nfserr && rqstp->rq_vers == 2)) { 785 xdr = proc->pc_encode; 786 if (xdr && !xdr(rqstp, nfserrp, 787 rqstp->rq_resp)) { 788 /* Failed to encode result. Release cache entry */ 789 dprintk("nfsd: failed to encode result!\n"); 790 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 791 *statp = rpc_system_err; 792 return 1; 793 } 794 } 795 796 /* Store reply in cache. */ 797 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1); 798 return 1; 799 } 800 801 int nfsd_pool_stats_open(struct inode *inode, struct file *file) 802 { 803 int ret; 804 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); 805 806 mutex_lock(&nfsd_mutex); 807 if (nn->nfsd_serv == NULL) { 808 mutex_unlock(&nfsd_mutex); 809 return -ENODEV; 810 } 811 /* bump up the psudo refcount while traversing */ 812 svc_get(nn->nfsd_serv); 813 ret = svc_pool_stats_open(nn->nfsd_serv, file); 814 mutex_unlock(&nfsd_mutex); 815 return ret; 816 } 817 818 int nfsd_pool_stats_release(struct inode *inode, struct file *file) 819 { 820 int ret = seq_release(inode, file); 821 struct net *net = inode->i_sb->s_fs_info; 822 823 mutex_lock(&nfsd_mutex); 824 /* this function really, really should have been called svc_put() */ 825 nfsd_destroy(net); 826 mutex_unlock(&nfsd_mutex); 827 return ret; 828 } 829