1 /* 2 * linux/fs/lockd/svc.c 3 * 4 * This is the central lockd service. 5 * 6 * FIXME: Separate the lockd NFS server functionality from the lockd NFS 7 * client functionality. Oh why didn't Sun create two separate 8 * services in the first place? 9 * 10 * Authors: Olaf Kirch (okir@monad.swb.de) 11 * 12 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 13 */ 14 15 #include <linux/module.h> 16 #include <linux/init.h> 17 #include <linux/sysctl.h> 18 #include <linux/moduleparam.h> 19 20 #include <linux/sched.h> 21 #include <linux/errno.h> 22 #include <linux/in.h> 23 #include <linux/uio.h> 24 #include <linux/smp.h> 25 #include <linux/mutex.h> 26 #include <linux/kthread.h> 27 #include <linux/freezer.h> 28 29 #include <linux/sunrpc/types.h> 30 #include <linux/sunrpc/stats.h> 31 #include <linux/sunrpc/clnt.h> 32 #include <linux/sunrpc/svc.h> 33 #include <linux/sunrpc/svcsock.h> 34 #include <net/ip.h> 35 #include <linux/lockd/lockd.h> 36 #include <linux/nfs.h> 37 38 #include "netns.h" 39 40 #define NLMDBG_FACILITY NLMDBG_SVC 41 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE) 42 #define ALLOWED_SIGS (sigmask(SIGKILL)) 43 44 static struct svc_program nlmsvc_program; 45 46 struct nlmsvc_binding * nlmsvc_ops; 47 EXPORT_SYMBOL_GPL(nlmsvc_ops); 48 49 static DEFINE_MUTEX(nlmsvc_mutex); 50 static unsigned int nlmsvc_users; 51 static struct task_struct *nlmsvc_task; 52 static struct svc_rqst *nlmsvc_rqst; 53 unsigned long nlmsvc_timeout; 54 55 int lockd_net_id; 56 57 /* 58 * These can be set at insmod time (useful for NFS as root filesystem), 59 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003 60 */ 61 static unsigned long nlm_grace_period; 62 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO; 63 static int nlm_udpport, nlm_tcpport; 64 65 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */ 66 static unsigned int nlm_max_connections = 1024; 67 68 /* 69 * Constants needed for the sysctl interface. 70 */ 71 static const unsigned long nlm_grace_period_min = 0; 72 static const unsigned long nlm_grace_period_max = 240; 73 static const unsigned long nlm_timeout_min = 3; 74 static const unsigned long nlm_timeout_max = 20; 75 static const int nlm_port_min = 0, nlm_port_max = 65535; 76 77 #ifdef CONFIG_SYSCTL 78 static struct ctl_table_header * nlm_sysctl_table; 79 #endif 80 81 static unsigned long get_lockd_grace_period(void) 82 { 83 /* Note: nlm_timeout should always be nonzero */ 84 if (nlm_grace_period) 85 return roundup(nlm_grace_period, nlm_timeout) * HZ; 86 else 87 return nlm_timeout * 5 * HZ; 88 } 89 90 static void grace_ender(struct work_struct *grace) 91 { 92 struct delayed_work *dwork = container_of(grace, struct delayed_work, 93 work); 94 struct lockd_net *ln = container_of(dwork, struct lockd_net, 95 grace_period_end); 96 97 locks_end_grace(&ln->lockd_manager); 98 } 99 100 static void set_grace_period(struct net *net) 101 { 102 unsigned long grace_period = get_lockd_grace_period(); 103 struct lockd_net *ln = net_generic(net, lockd_net_id); 104 105 locks_start_grace(net, &ln->lockd_manager); 106 cancel_delayed_work_sync(&ln->grace_period_end); 107 schedule_delayed_work(&ln->grace_period_end, grace_period); 108 } 109 110 static void restart_grace(void) 111 { 112 if (nlmsvc_ops) { 113 struct net *net = &init_net; 114 struct lockd_net *ln = net_generic(net, lockd_net_id); 115 116 cancel_delayed_work_sync(&ln->grace_period_end); 117 locks_end_grace(&ln->lockd_manager); 118 nlmsvc_invalidate_all(); 119 set_grace_period(net); 120 } 121 } 122 123 /* 124 * This is the lockd kernel thread 125 */ 126 static int 127 lockd(void *vrqstp) 128 { 129 int err = 0; 130 struct svc_rqst *rqstp = vrqstp; 131 132 /* try_to_freeze() is called from svc_recv() */ 133 set_freezable(); 134 135 /* Allow SIGKILL to tell lockd to drop all of its locks */ 136 allow_signal(SIGKILL); 137 138 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n"); 139 140 if (!nlm_timeout) 141 nlm_timeout = LOCKD_DFLT_TIMEO; 142 nlmsvc_timeout = nlm_timeout * HZ; 143 144 /* 145 * The main request loop. We don't terminate until the last 146 * NFS mount or NFS daemon has gone away. 147 */ 148 while (!kthread_should_stop()) { 149 long timeout = MAX_SCHEDULE_TIMEOUT; 150 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 151 152 /* update sv_maxconn if it has changed */ 153 rqstp->rq_server->sv_maxconn = nlm_max_connections; 154 155 if (signalled()) { 156 flush_signals(current); 157 restart_grace(); 158 continue; 159 } 160 161 timeout = nlmsvc_retry_blocked(); 162 163 /* 164 * Find a socket with data available and call its 165 * recvfrom routine. 166 */ 167 err = svc_recv(rqstp, timeout); 168 if (err == -EAGAIN || err == -EINTR) 169 continue; 170 dprintk("lockd: request from %s\n", 171 svc_print_addr(rqstp, buf, sizeof(buf))); 172 173 svc_process(rqstp); 174 } 175 flush_signals(current); 176 if (nlmsvc_ops) 177 nlmsvc_invalidate_all(); 178 nlm_shutdown_hosts(); 179 return 0; 180 } 181 182 static int create_lockd_listener(struct svc_serv *serv, const char *name, 183 struct net *net, const int family, 184 const unsigned short port) 185 { 186 struct svc_xprt *xprt; 187 188 xprt = svc_find_xprt(serv, name, net, family, 0); 189 if (xprt == NULL) 190 return svc_create_xprt(serv, name, net, family, port, 191 SVC_SOCK_DEFAULTS); 192 svc_xprt_put(xprt); 193 return 0; 194 } 195 196 static int create_lockd_family(struct svc_serv *serv, struct net *net, 197 const int family) 198 { 199 int err; 200 201 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport); 202 if (err < 0) 203 return err; 204 205 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport); 206 } 207 208 /* 209 * Ensure there are active UDP and TCP listeners for lockd. 210 * 211 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some 212 * local services (such as rpc.statd) still require UDP, and 213 * some NFS servers do not yet support NLM over TCP. 214 * 215 * Returns zero if all listeners are available; otherwise a 216 * negative errno value is returned. 217 */ 218 static int make_socks(struct svc_serv *serv, struct net *net) 219 { 220 static int warned; 221 int err; 222 223 err = create_lockd_family(serv, net, PF_INET); 224 if (err < 0) 225 goto out_err; 226 227 err = create_lockd_family(serv, net, PF_INET6); 228 if (err < 0 && err != -EAFNOSUPPORT) 229 goto out_err; 230 231 warned = 0; 232 return 0; 233 234 out_err: 235 if (warned++ == 0) 236 printk(KERN_WARNING 237 "lockd_up: makesock failed, error=%d\n", err); 238 svc_shutdown_net(serv, net); 239 return err; 240 } 241 242 static int lockd_up_net(struct svc_serv *serv, struct net *net) 243 { 244 struct lockd_net *ln = net_generic(net, lockd_net_id); 245 int error; 246 247 if (ln->nlmsvc_users++) 248 return 0; 249 250 error = svc_bind(serv, net); 251 if (error) 252 goto err_bind; 253 254 error = make_socks(serv, net); 255 if (error < 0) 256 goto err_socks; 257 set_grace_period(net); 258 dprintk("lockd_up_net: per-net data created; net=%p\n", net); 259 return 0; 260 261 err_socks: 262 svc_rpcb_cleanup(serv, net); 263 err_bind: 264 ln->nlmsvc_users--; 265 return error; 266 } 267 268 static void lockd_down_net(struct svc_serv *serv, struct net *net) 269 { 270 struct lockd_net *ln = net_generic(net, lockd_net_id); 271 272 if (ln->nlmsvc_users) { 273 if (--ln->nlmsvc_users == 0) { 274 nlm_shutdown_hosts_net(net); 275 cancel_delayed_work_sync(&ln->grace_period_end); 276 locks_end_grace(&ln->lockd_manager); 277 svc_shutdown_net(serv, net); 278 dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net); 279 } 280 } else { 281 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n", 282 nlmsvc_task, net); 283 BUG(); 284 } 285 } 286 287 static int lockd_start_svc(struct svc_serv *serv) 288 { 289 int error; 290 291 if (nlmsvc_rqst) 292 return 0; 293 294 /* 295 * Create the kernel thread and wait for it to start. 296 */ 297 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE); 298 if (IS_ERR(nlmsvc_rqst)) { 299 error = PTR_ERR(nlmsvc_rqst); 300 printk(KERN_WARNING 301 "lockd_up: svc_rqst allocation failed, error=%d\n", 302 error); 303 goto out_rqst; 304 } 305 306 svc_sock_update_bufs(serv); 307 serv->sv_maxconn = nlm_max_connections; 308 309 nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name); 310 if (IS_ERR(nlmsvc_task)) { 311 error = PTR_ERR(nlmsvc_task); 312 printk(KERN_WARNING 313 "lockd_up: kthread_run failed, error=%d\n", error); 314 goto out_task; 315 } 316 nlmsvc_rqst->rq_task = nlmsvc_task; 317 wake_up_process(nlmsvc_task); 318 319 dprintk("lockd_up: service started\n"); 320 return 0; 321 322 out_task: 323 svc_exit_thread(nlmsvc_rqst); 324 nlmsvc_task = NULL; 325 out_rqst: 326 nlmsvc_rqst = NULL; 327 return error; 328 } 329 330 static struct svc_serv *lockd_create_svc(void) 331 { 332 struct svc_serv *serv; 333 334 /* 335 * Check whether we're already up and running. 336 */ 337 if (nlmsvc_rqst) { 338 /* 339 * Note: increase service usage, because later in case of error 340 * svc_destroy() will be called. 341 */ 342 svc_get(nlmsvc_rqst->rq_server); 343 return nlmsvc_rqst->rq_server; 344 } 345 346 /* 347 * Sanity check: if there's no pid, 348 * we should be the first user ... 349 */ 350 if (nlmsvc_users) 351 printk(KERN_WARNING 352 "lockd_up: no pid, %d users??\n", nlmsvc_users); 353 354 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL); 355 if (!serv) { 356 printk(KERN_WARNING "lockd_up: create service failed\n"); 357 return ERR_PTR(-ENOMEM); 358 } 359 dprintk("lockd_up: service created\n"); 360 return serv; 361 } 362 363 /* 364 * Bring up the lockd process if it's not already up. 365 */ 366 int lockd_up(struct net *net) 367 { 368 struct svc_serv *serv; 369 int error; 370 371 mutex_lock(&nlmsvc_mutex); 372 373 serv = lockd_create_svc(); 374 if (IS_ERR(serv)) { 375 error = PTR_ERR(serv); 376 goto err_create; 377 } 378 379 error = lockd_up_net(serv, net); 380 if (error < 0) 381 goto err_net; 382 383 error = lockd_start_svc(serv); 384 if (error < 0) 385 goto err_start; 386 387 nlmsvc_users++; 388 /* 389 * Note: svc_serv structures have an initial use count of 1, 390 * so we exit through here on both success and failure. 391 */ 392 err_net: 393 svc_destroy(serv); 394 err_create: 395 mutex_unlock(&nlmsvc_mutex); 396 return error; 397 398 err_start: 399 lockd_down_net(serv, net); 400 goto err_net; 401 } 402 EXPORT_SYMBOL_GPL(lockd_up); 403 404 /* 405 * Decrement the user count and bring down lockd if we're the last. 406 */ 407 void 408 lockd_down(struct net *net) 409 { 410 mutex_lock(&nlmsvc_mutex); 411 lockd_down_net(nlmsvc_rqst->rq_server, net); 412 if (nlmsvc_users) { 413 if (--nlmsvc_users) 414 goto out; 415 } else { 416 printk(KERN_ERR "lockd_down: no users! task=%p\n", 417 nlmsvc_task); 418 BUG(); 419 } 420 421 if (!nlmsvc_task) { 422 printk(KERN_ERR "lockd_down: no lockd running.\n"); 423 BUG(); 424 } 425 kthread_stop(nlmsvc_task); 426 dprintk("lockd_down: service stopped\n"); 427 svc_exit_thread(nlmsvc_rqst); 428 dprintk("lockd_down: service destroyed\n"); 429 nlmsvc_task = NULL; 430 nlmsvc_rqst = NULL; 431 out: 432 mutex_unlock(&nlmsvc_mutex); 433 } 434 EXPORT_SYMBOL_GPL(lockd_down); 435 436 #ifdef CONFIG_SYSCTL 437 438 /* 439 * Sysctl parameters (same as module parameters, different interface). 440 */ 441 442 static struct ctl_table nlm_sysctls[] = { 443 { 444 .procname = "nlm_grace_period", 445 .data = &nlm_grace_period, 446 .maxlen = sizeof(unsigned long), 447 .mode = 0644, 448 .proc_handler = proc_doulongvec_minmax, 449 .extra1 = (unsigned long *) &nlm_grace_period_min, 450 .extra2 = (unsigned long *) &nlm_grace_period_max, 451 }, 452 { 453 .procname = "nlm_timeout", 454 .data = &nlm_timeout, 455 .maxlen = sizeof(unsigned long), 456 .mode = 0644, 457 .proc_handler = proc_doulongvec_minmax, 458 .extra1 = (unsigned long *) &nlm_timeout_min, 459 .extra2 = (unsigned long *) &nlm_timeout_max, 460 }, 461 { 462 .procname = "nlm_udpport", 463 .data = &nlm_udpport, 464 .maxlen = sizeof(int), 465 .mode = 0644, 466 .proc_handler = proc_dointvec_minmax, 467 .extra1 = (int *) &nlm_port_min, 468 .extra2 = (int *) &nlm_port_max, 469 }, 470 { 471 .procname = "nlm_tcpport", 472 .data = &nlm_tcpport, 473 .maxlen = sizeof(int), 474 .mode = 0644, 475 .proc_handler = proc_dointvec_minmax, 476 .extra1 = (int *) &nlm_port_min, 477 .extra2 = (int *) &nlm_port_max, 478 }, 479 { 480 .procname = "nsm_use_hostnames", 481 .data = &nsm_use_hostnames, 482 .maxlen = sizeof(int), 483 .mode = 0644, 484 .proc_handler = proc_dointvec, 485 }, 486 { 487 .procname = "nsm_local_state", 488 .data = &nsm_local_state, 489 .maxlen = sizeof(int), 490 .mode = 0644, 491 .proc_handler = proc_dointvec, 492 }, 493 { } 494 }; 495 496 static struct ctl_table nlm_sysctl_dir[] = { 497 { 498 .procname = "nfs", 499 .mode = 0555, 500 .child = nlm_sysctls, 501 }, 502 { } 503 }; 504 505 static struct ctl_table nlm_sysctl_root[] = { 506 { 507 .procname = "fs", 508 .mode = 0555, 509 .child = nlm_sysctl_dir, 510 }, 511 { } 512 }; 513 514 #endif /* CONFIG_SYSCTL */ 515 516 /* 517 * Module (and sysfs) parameters. 518 */ 519 520 #define param_set_min_max(name, type, which_strtol, min, max) \ 521 static int param_set_##name(const char *val, struct kernel_param *kp) \ 522 { \ 523 char *endp; \ 524 __typeof__(type) num = which_strtol(val, &endp, 0); \ 525 if (endp == val || *endp || num < (min) || num > (max)) \ 526 return -EINVAL; \ 527 *((type *) kp->arg) = num; \ 528 return 0; \ 529 } 530 531 static inline int is_callback(u32 proc) 532 { 533 return proc == NLMPROC_GRANTED 534 || proc == NLMPROC_GRANTED_MSG 535 || proc == NLMPROC_TEST_RES 536 || proc == NLMPROC_LOCK_RES 537 || proc == NLMPROC_CANCEL_RES 538 || proc == NLMPROC_UNLOCK_RES 539 || proc == NLMPROC_NSM_NOTIFY; 540 } 541 542 543 static int lockd_authenticate(struct svc_rqst *rqstp) 544 { 545 rqstp->rq_client = NULL; 546 switch (rqstp->rq_authop->flavour) { 547 case RPC_AUTH_NULL: 548 case RPC_AUTH_UNIX: 549 if (rqstp->rq_proc == 0) 550 return SVC_OK; 551 if (is_callback(rqstp->rq_proc)) { 552 /* Leave it to individual procedures to 553 * call nlmsvc_lookup_host(rqstp) 554 */ 555 return SVC_OK; 556 } 557 return svc_set_client(rqstp); 558 } 559 return SVC_DENIED; 560 } 561 562 563 param_set_min_max(port, int, simple_strtol, 0, 65535) 564 param_set_min_max(grace_period, unsigned long, simple_strtoul, 565 nlm_grace_period_min, nlm_grace_period_max) 566 param_set_min_max(timeout, unsigned long, simple_strtoul, 567 nlm_timeout_min, nlm_timeout_max) 568 569 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>"); 570 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION "."); 571 MODULE_LICENSE("GPL"); 572 573 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong, 574 &nlm_grace_period, 0644); 575 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong, 576 &nlm_timeout, 0644); 577 module_param_call(nlm_udpport, param_set_port, param_get_int, 578 &nlm_udpport, 0644); 579 module_param_call(nlm_tcpport, param_set_port, param_get_int, 580 &nlm_tcpport, 0644); 581 module_param(nsm_use_hostnames, bool, 0644); 582 module_param(nlm_max_connections, uint, 0644); 583 584 static int lockd_init_net(struct net *net) 585 { 586 struct lockd_net *ln = net_generic(net, lockd_net_id); 587 588 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender); 589 INIT_LIST_HEAD(&ln->lockd_manager.list); 590 spin_lock_init(&ln->nsm_clnt_lock); 591 return 0; 592 } 593 594 static void lockd_exit_net(struct net *net) 595 { 596 } 597 598 static struct pernet_operations lockd_net_ops = { 599 .init = lockd_init_net, 600 .exit = lockd_exit_net, 601 .id = &lockd_net_id, 602 .size = sizeof(struct lockd_net), 603 }; 604 605 606 /* 607 * Initialising and terminating the module. 608 */ 609 610 static int __init init_nlm(void) 611 { 612 int err; 613 614 #ifdef CONFIG_SYSCTL 615 err = -ENOMEM; 616 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root); 617 if (nlm_sysctl_table == NULL) 618 goto err_sysctl; 619 #endif 620 err = register_pernet_subsys(&lockd_net_ops); 621 if (err) 622 goto err_pernet; 623 return 0; 624 625 err_pernet: 626 #ifdef CONFIG_SYSCTL 627 unregister_sysctl_table(nlm_sysctl_table); 628 err_sysctl: 629 #endif 630 return err; 631 } 632 633 static void __exit exit_nlm(void) 634 { 635 /* FIXME: delete all NLM clients */ 636 nlm_shutdown_hosts(); 637 unregister_pernet_subsys(&lockd_net_ops); 638 #ifdef CONFIG_SYSCTL 639 unregister_sysctl_table(nlm_sysctl_table); 640 #endif 641 } 642 643 module_init(init_nlm); 644 module_exit(exit_nlm); 645 646 /* 647 * Define NLM program and procedures 648 */ 649 static struct svc_version nlmsvc_version1 = { 650 .vs_vers = 1, 651 .vs_nproc = 17, 652 .vs_proc = nlmsvc_procedures, 653 .vs_xdrsize = NLMSVC_XDRSIZE, 654 }; 655 static struct svc_version nlmsvc_version3 = { 656 .vs_vers = 3, 657 .vs_nproc = 24, 658 .vs_proc = nlmsvc_procedures, 659 .vs_xdrsize = NLMSVC_XDRSIZE, 660 }; 661 #ifdef CONFIG_LOCKD_V4 662 static struct svc_version nlmsvc_version4 = { 663 .vs_vers = 4, 664 .vs_nproc = 24, 665 .vs_proc = nlmsvc_procedures4, 666 .vs_xdrsize = NLMSVC_XDRSIZE, 667 }; 668 #endif 669 static struct svc_version * nlmsvc_version[] = { 670 [1] = &nlmsvc_version1, 671 [3] = &nlmsvc_version3, 672 #ifdef CONFIG_LOCKD_V4 673 [4] = &nlmsvc_version4, 674 #endif 675 }; 676 677 static struct svc_stat nlmsvc_stats; 678 679 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version) 680 static struct svc_program nlmsvc_program = { 681 .pg_prog = NLM_PROGRAM, /* program number */ 682 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */ 683 .pg_vers = nlmsvc_version, /* version table */ 684 .pg_name = "lockd", /* service name */ 685 .pg_class = "nfsd", /* share authentication with nfsd */ 686 .pg_stats = &nlmsvc_stats, /* stats table */ 687 .pg_authenticate = &lockd_authenticate /* export authentication */ 688 }; 689