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 /* Only used under nfsd_mutex, so this atomic may be overkill: */ 370 static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0); 371 372 static void nfsd_last_thread(struct svc_serv *serv, struct net *net) 373 { 374 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 375 376 /* check if the notifier still has clients */ 377 if (atomic_dec_return(&nfsd_notifier_refcount) == 0) { 378 unregister_inetaddr_notifier(&nfsd_inetaddr_notifier); 379 #if IS_ENABLED(CONFIG_IPV6) 380 unregister_inet6addr_notifier(&nfsd_inet6addr_notifier); 381 #endif 382 } 383 384 /* 385 * write_ports can create the server without actually starting 386 * any threads--if we get shut down before any threads are 387 * started, then nfsd_last_thread will be run before any of this 388 * other initialization has been done except the rpcb information. 389 */ 390 svc_rpcb_cleanup(serv, net); 391 if (!nn->nfsd_net_up) 392 return; 393 394 nfsd_shutdown_net(net); 395 printk(KERN_WARNING "nfsd: last server has exited, flushing export " 396 "cache\n"); 397 nfsd_export_flush(net); 398 } 399 400 void nfsd_reset_versions(void) 401 { 402 int found_one = 0; 403 int i; 404 405 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { 406 if (nfsd_program.pg_vers[i]) 407 found_one = 1; 408 } 409 410 if (!found_one) { 411 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) 412 nfsd_program.pg_vers[i] = nfsd_version[i]; 413 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 414 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) 415 nfsd_acl_program.pg_vers[i] = 416 nfsd_acl_version[i]; 417 #endif 418 } 419 } 420 421 /* 422 * Each session guarantees a negotiated per slot memory cache for replies 423 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated 424 * NFSv4.1 server might want to use more memory for a DRC than a machine 425 * with mutiple services. 426 * 427 * Impose a hard limit on the number of pages for the DRC which varies 428 * according to the machines free pages. This is of course only a default. 429 * 430 * For now this is a #defined shift which could be under admin control 431 * in the future. 432 */ 433 static void set_max_drc(void) 434 { 435 #define NFSD_DRC_SIZE_SHIFT 10 436 nfsd_drc_max_mem = (nr_free_buffer_pages() 437 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE; 438 nfsd_drc_mem_used = 0; 439 spin_lock_init(&nfsd_drc_lock); 440 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem); 441 } 442 443 static int nfsd_get_default_max_blksize(void) 444 { 445 struct sysinfo i; 446 unsigned long long target; 447 unsigned long ret; 448 449 si_meminfo(&i); 450 target = (i.totalram - i.totalhigh) << PAGE_SHIFT; 451 /* 452 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig 453 * machines, but only uses 32K on 128M machines. Bottom out at 454 * 8K on 32M and smaller. Of course, this is only a default. 455 */ 456 target >>= 12; 457 458 ret = NFSSVC_MAXBLKSIZE; 459 while (ret > target && ret >= 8*1024*2) 460 ret /= 2; 461 return ret; 462 } 463 464 static struct svc_serv_ops nfsd_thread_sv_ops = { 465 .svo_shutdown = nfsd_last_thread, 466 .svo_function = nfsd, 467 .svo_enqueue_xprt = svc_xprt_do_enqueue, 468 .svo_setup = svc_set_num_threads, 469 .svo_module = THIS_MODULE, 470 }; 471 472 int nfsd_create_serv(struct net *net) 473 { 474 int error; 475 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 476 477 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 478 if (nn->nfsd_serv) { 479 svc_get(nn->nfsd_serv); 480 return 0; 481 } 482 if (nfsd_max_blksize == 0) 483 nfsd_max_blksize = nfsd_get_default_max_blksize(); 484 nfsd_reset_versions(); 485 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize, 486 &nfsd_thread_sv_ops); 487 if (nn->nfsd_serv == NULL) 488 return -ENOMEM; 489 490 nn->nfsd_serv->sv_maxconn = nn->max_connections; 491 error = svc_bind(nn->nfsd_serv, net); 492 if (error < 0) { 493 svc_destroy(nn->nfsd_serv); 494 return error; 495 } 496 497 set_max_drc(); 498 /* check if the notifier is already set */ 499 if (atomic_inc_return(&nfsd_notifier_refcount) == 1) { 500 register_inetaddr_notifier(&nfsd_inetaddr_notifier); 501 #if IS_ENABLED(CONFIG_IPV6) 502 register_inet6addr_notifier(&nfsd_inet6addr_notifier); 503 #endif 504 } 505 do_gettimeofday(&nn->nfssvc_boot); /* record boot time */ 506 return 0; 507 } 508 509 int nfsd_nrpools(struct net *net) 510 { 511 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 512 513 if (nn->nfsd_serv == NULL) 514 return 0; 515 else 516 return nn->nfsd_serv->sv_nrpools; 517 } 518 519 int nfsd_get_nrthreads(int n, int *nthreads, struct net *net) 520 { 521 int i = 0; 522 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 523 524 if (nn->nfsd_serv != NULL) { 525 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++) 526 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads; 527 } 528 529 return 0; 530 } 531 532 void nfsd_destroy(struct net *net) 533 { 534 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 535 int destroy = (nn->nfsd_serv->sv_nrthreads == 1); 536 537 if (destroy) 538 svc_shutdown_net(nn->nfsd_serv, net); 539 svc_destroy(nn->nfsd_serv); 540 if (destroy) 541 nn->nfsd_serv = NULL; 542 } 543 544 int nfsd_set_nrthreads(int n, int *nthreads, struct net *net) 545 { 546 int i = 0; 547 int tot = 0; 548 int err = 0; 549 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 550 551 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 552 553 if (nn->nfsd_serv == NULL || n <= 0) 554 return 0; 555 556 if (n > nn->nfsd_serv->sv_nrpools) 557 n = nn->nfsd_serv->sv_nrpools; 558 559 /* enforce a global maximum number of threads */ 560 tot = 0; 561 for (i = 0; i < n; i++) { 562 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS); 563 tot += nthreads[i]; 564 } 565 if (tot > NFSD_MAXSERVS) { 566 /* total too large: scale down requested numbers */ 567 for (i = 0; i < n && tot > 0; i++) { 568 int new = nthreads[i] * NFSD_MAXSERVS / tot; 569 tot -= (nthreads[i] - new); 570 nthreads[i] = new; 571 } 572 for (i = 0; i < n && tot > 0; i++) { 573 nthreads[i]--; 574 tot--; 575 } 576 } 577 578 /* 579 * There must always be a thread in pool 0; the admin 580 * can't shut down NFS completely using pool_threads. 581 */ 582 if (nthreads[0] == 0) 583 nthreads[0] = 1; 584 585 /* apply the new numbers */ 586 svc_get(nn->nfsd_serv); 587 for (i = 0; i < n; i++) { 588 err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv, 589 &nn->nfsd_serv->sv_pools[i], nthreads[i]); 590 if (err) 591 break; 592 } 593 nfsd_destroy(net); 594 return err; 595 } 596 597 /* 598 * Adjust the number of threads and return the new number of threads. 599 * This is also the function that starts the server if necessary, if 600 * this is the first time nrservs is nonzero. 601 */ 602 int 603 nfsd_svc(int nrservs, struct net *net) 604 { 605 int error; 606 bool nfsd_up_before; 607 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 608 609 mutex_lock(&nfsd_mutex); 610 dprintk("nfsd: creating service\n"); 611 612 nrservs = max(nrservs, 0); 613 nrservs = min(nrservs, NFSD_MAXSERVS); 614 error = 0; 615 616 if (nrservs == 0 && nn->nfsd_serv == NULL) 617 goto out; 618 619 error = nfsd_create_serv(net); 620 if (error) 621 goto out; 622 623 nfsd_up_before = nn->nfsd_net_up; 624 625 error = nfsd_startup_net(nrservs, net); 626 if (error) 627 goto out_destroy; 628 error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv, 629 NULL, nrservs); 630 if (error) 631 goto out_shutdown; 632 /* We are holding a reference to nn->nfsd_serv which 633 * we don't want to count in the return value, 634 * so subtract 1 635 */ 636 error = nn->nfsd_serv->sv_nrthreads - 1; 637 out_shutdown: 638 if (error < 0 && !nfsd_up_before) 639 nfsd_shutdown_net(net); 640 out_destroy: 641 nfsd_destroy(net); /* Release server */ 642 out: 643 mutex_unlock(&nfsd_mutex); 644 return error; 645 } 646 647 648 /* 649 * This is the NFS server kernel thread 650 */ 651 static int 652 nfsd(void *vrqstp) 653 { 654 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; 655 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list); 656 struct net *net = perm_sock->xpt_net; 657 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 658 int err; 659 660 /* Lock module and set up kernel thread */ 661 mutex_lock(&nfsd_mutex); 662 663 /* At this point, the thread shares current->fs 664 * with the init process. We need to create files with a 665 * umask of 0 instead of init's umask. */ 666 if (unshare_fs_struct() < 0) { 667 printk("Unable to start nfsd thread: out of memory\n"); 668 goto out; 669 } 670 671 current->fs->umask = 0; 672 673 /* 674 * thread is spawned with all signals set to SIG_IGN, re-enable 675 * the ones that will bring down the thread 676 */ 677 allow_signal(SIGKILL); 678 allow_signal(SIGHUP); 679 allow_signal(SIGINT); 680 allow_signal(SIGQUIT); 681 682 nfsdstats.th_cnt++; 683 mutex_unlock(&nfsd_mutex); 684 685 set_freezable(); 686 687 /* 688 * The main request loop 689 */ 690 for (;;) { 691 /* Update sv_maxconn if it has changed */ 692 rqstp->rq_server->sv_maxconn = nn->max_connections; 693 694 /* 695 * Find a socket with data available and call its 696 * recvfrom routine. 697 */ 698 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN) 699 ; 700 if (err == -EINTR) 701 break; 702 validate_process_creds(); 703 svc_process(rqstp); 704 validate_process_creds(); 705 } 706 707 /* Clear signals before calling svc_exit_thread() */ 708 flush_signals(current); 709 710 mutex_lock(&nfsd_mutex); 711 nfsdstats.th_cnt --; 712 713 out: 714 rqstp->rq_server = NULL; 715 716 /* Release the thread */ 717 svc_exit_thread(rqstp); 718 719 nfsd_destroy(net); 720 721 /* Release module */ 722 mutex_unlock(&nfsd_mutex); 723 module_put_and_exit(0); 724 return 0; 725 } 726 727 static __be32 map_new_errors(u32 vers, __be32 nfserr) 728 { 729 if (nfserr == nfserr_jukebox && vers == 2) 730 return nfserr_dropit; 731 if (nfserr == nfserr_wrongsec && vers < 4) 732 return nfserr_acces; 733 return nfserr; 734 } 735 736 int 737 nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) 738 { 739 struct svc_procedure *proc; 740 kxdrproc_t xdr; 741 __be32 nfserr; 742 __be32 *nfserrp; 743 744 dprintk("nfsd_dispatch: vers %d proc %d\n", 745 rqstp->rq_vers, rqstp->rq_proc); 746 proc = rqstp->rq_procinfo; 747 748 /* 749 * Give the xdr decoder a chance to change this if it wants 750 * (necessary in the NFSv4.0 compound case) 751 */ 752 rqstp->rq_cachetype = proc->pc_cachetype; 753 /* Decode arguments */ 754 xdr = proc->pc_decode; 755 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base, 756 rqstp->rq_argp)) { 757 dprintk("nfsd: failed to decode arguments!\n"); 758 *statp = rpc_garbage_args; 759 return 1; 760 } 761 762 /* Check whether we have this call in the cache. */ 763 switch (nfsd_cache_lookup(rqstp)) { 764 case RC_DROPIT: 765 return 0; 766 case RC_REPLY: 767 return 1; 768 case RC_DOIT:; 769 /* do it */ 770 } 771 772 /* need to grab the location to store the status, as 773 * nfsv4 does some encoding while processing 774 */ 775 nfserrp = rqstp->rq_res.head[0].iov_base 776 + rqstp->rq_res.head[0].iov_len; 777 rqstp->rq_res.head[0].iov_len += sizeof(__be32); 778 779 /* Now call the procedure handler, and encode NFS status. */ 780 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); 781 nfserr = map_new_errors(rqstp->rq_vers, nfserr); 782 if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) { 783 dprintk("nfsd: Dropping request; may be revisited later\n"); 784 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 785 return 0; 786 } 787 788 if (rqstp->rq_proc != 0) 789 *nfserrp++ = nfserr; 790 791 /* Encode result. 792 * For NFSv2, additional info is never returned in case of an error. 793 */ 794 if (!(nfserr && rqstp->rq_vers == 2)) { 795 xdr = proc->pc_encode; 796 if (xdr && !xdr(rqstp, nfserrp, 797 rqstp->rq_resp)) { 798 /* Failed to encode result. Release cache entry */ 799 dprintk("nfsd: failed to encode result!\n"); 800 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 801 *statp = rpc_system_err; 802 return 1; 803 } 804 } 805 806 /* Store reply in cache. */ 807 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1); 808 return 1; 809 } 810 811 int nfsd_pool_stats_open(struct inode *inode, struct file *file) 812 { 813 int ret; 814 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); 815 816 mutex_lock(&nfsd_mutex); 817 if (nn->nfsd_serv == NULL) { 818 mutex_unlock(&nfsd_mutex); 819 return -ENODEV; 820 } 821 /* bump up the psudo refcount while traversing */ 822 svc_get(nn->nfsd_serv); 823 ret = svc_pool_stats_open(nn->nfsd_serv, file); 824 mutex_unlock(&nfsd_mutex); 825 return ret; 826 } 827 828 int nfsd_pool_stats_release(struct inode *inode, struct file *file) 829 { 830 int ret = seq_release(inode, file); 831 struct net *net = inode->i_sb->s_fs_info; 832 833 mutex_lock(&nfsd_mutex); 834 /* this function really, really should have been called svc_put() */ 835 nfsd_destroy(net); 836 mutex_unlock(&nfsd_mutex); 837 return ret; 838 } 839