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_run(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 dprintk("lockd_up: service started\n"); 317 return 0; 318 319 out_task: 320 svc_exit_thread(nlmsvc_rqst); 321 nlmsvc_task = NULL; 322 out_rqst: 323 nlmsvc_rqst = NULL; 324 return error; 325 } 326 327 static struct svc_serv *lockd_create_svc(void) 328 { 329 struct svc_serv *serv; 330 331 /* 332 * Check whether we're already up and running. 333 */ 334 if (nlmsvc_rqst) { 335 /* 336 * Note: increase service usage, because later in case of error 337 * svc_destroy() will be called. 338 */ 339 svc_get(nlmsvc_rqst->rq_server); 340 return nlmsvc_rqst->rq_server; 341 } 342 343 /* 344 * Sanity check: if there's no pid, 345 * we should be the first user ... 346 */ 347 if (nlmsvc_users) 348 printk(KERN_WARNING 349 "lockd_up: no pid, %d users??\n", nlmsvc_users); 350 351 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL); 352 if (!serv) { 353 printk(KERN_WARNING "lockd_up: create service failed\n"); 354 return ERR_PTR(-ENOMEM); 355 } 356 dprintk("lockd_up: service created\n"); 357 return serv; 358 } 359 360 /* 361 * Bring up the lockd process if it's not already up. 362 */ 363 int lockd_up(struct net *net) 364 { 365 struct svc_serv *serv; 366 int error; 367 368 mutex_lock(&nlmsvc_mutex); 369 370 serv = lockd_create_svc(); 371 if (IS_ERR(serv)) { 372 error = PTR_ERR(serv); 373 goto err_create; 374 } 375 376 error = lockd_up_net(serv, net); 377 if (error < 0) 378 goto err_net; 379 380 error = lockd_start_svc(serv); 381 if (error < 0) 382 goto err_start; 383 384 nlmsvc_users++; 385 /* 386 * Note: svc_serv structures have an initial use count of 1, 387 * so we exit through here on both success and failure. 388 */ 389 err_net: 390 svc_destroy(serv); 391 err_create: 392 mutex_unlock(&nlmsvc_mutex); 393 return error; 394 395 err_start: 396 lockd_down_net(serv, net); 397 goto err_net; 398 } 399 EXPORT_SYMBOL_GPL(lockd_up); 400 401 /* 402 * Decrement the user count and bring down lockd if we're the last. 403 */ 404 void 405 lockd_down(struct net *net) 406 { 407 mutex_lock(&nlmsvc_mutex); 408 lockd_down_net(nlmsvc_rqst->rq_server, net); 409 if (nlmsvc_users) { 410 if (--nlmsvc_users) 411 goto out; 412 } else { 413 printk(KERN_ERR "lockd_down: no users! task=%p\n", 414 nlmsvc_task); 415 BUG(); 416 } 417 418 if (!nlmsvc_task) { 419 printk(KERN_ERR "lockd_down: no lockd running.\n"); 420 BUG(); 421 } 422 kthread_stop(nlmsvc_task); 423 dprintk("lockd_down: service stopped\n"); 424 svc_exit_thread(nlmsvc_rqst); 425 dprintk("lockd_down: service destroyed\n"); 426 nlmsvc_task = NULL; 427 nlmsvc_rqst = NULL; 428 out: 429 mutex_unlock(&nlmsvc_mutex); 430 } 431 EXPORT_SYMBOL_GPL(lockd_down); 432 433 #ifdef CONFIG_SYSCTL 434 435 /* 436 * Sysctl parameters (same as module parameters, different interface). 437 */ 438 439 static struct ctl_table nlm_sysctls[] = { 440 { 441 .procname = "nlm_grace_period", 442 .data = &nlm_grace_period, 443 .maxlen = sizeof(unsigned long), 444 .mode = 0644, 445 .proc_handler = proc_doulongvec_minmax, 446 .extra1 = (unsigned long *) &nlm_grace_period_min, 447 .extra2 = (unsigned long *) &nlm_grace_period_max, 448 }, 449 { 450 .procname = "nlm_timeout", 451 .data = &nlm_timeout, 452 .maxlen = sizeof(unsigned long), 453 .mode = 0644, 454 .proc_handler = proc_doulongvec_minmax, 455 .extra1 = (unsigned long *) &nlm_timeout_min, 456 .extra2 = (unsigned long *) &nlm_timeout_max, 457 }, 458 { 459 .procname = "nlm_udpport", 460 .data = &nlm_udpport, 461 .maxlen = sizeof(int), 462 .mode = 0644, 463 .proc_handler = proc_dointvec_minmax, 464 .extra1 = (int *) &nlm_port_min, 465 .extra2 = (int *) &nlm_port_max, 466 }, 467 { 468 .procname = "nlm_tcpport", 469 .data = &nlm_tcpport, 470 .maxlen = sizeof(int), 471 .mode = 0644, 472 .proc_handler = proc_dointvec_minmax, 473 .extra1 = (int *) &nlm_port_min, 474 .extra2 = (int *) &nlm_port_max, 475 }, 476 { 477 .procname = "nsm_use_hostnames", 478 .data = &nsm_use_hostnames, 479 .maxlen = sizeof(int), 480 .mode = 0644, 481 .proc_handler = proc_dointvec, 482 }, 483 { 484 .procname = "nsm_local_state", 485 .data = &nsm_local_state, 486 .maxlen = sizeof(int), 487 .mode = 0644, 488 .proc_handler = proc_dointvec, 489 }, 490 { } 491 }; 492 493 static struct ctl_table nlm_sysctl_dir[] = { 494 { 495 .procname = "nfs", 496 .mode = 0555, 497 .child = nlm_sysctls, 498 }, 499 { } 500 }; 501 502 static struct ctl_table nlm_sysctl_root[] = { 503 { 504 .procname = "fs", 505 .mode = 0555, 506 .child = nlm_sysctl_dir, 507 }, 508 { } 509 }; 510 511 #endif /* CONFIG_SYSCTL */ 512 513 /* 514 * Module (and sysfs) parameters. 515 */ 516 517 #define param_set_min_max(name, type, which_strtol, min, max) \ 518 static int param_set_##name(const char *val, struct kernel_param *kp) \ 519 { \ 520 char *endp; \ 521 __typeof__(type) num = which_strtol(val, &endp, 0); \ 522 if (endp == val || *endp || num < (min) || num > (max)) \ 523 return -EINVAL; \ 524 *((type *) kp->arg) = num; \ 525 return 0; \ 526 } 527 528 static inline int is_callback(u32 proc) 529 { 530 return proc == NLMPROC_GRANTED 531 || proc == NLMPROC_GRANTED_MSG 532 || proc == NLMPROC_TEST_RES 533 || proc == NLMPROC_LOCK_RES 534 || proc == NLMPROC_CANCEL_RES 535 || proc == NLMPROC_UNLOCK_RES 536 || proc == NLMPROC_NSM_NOTIFY; 537 } 538 539 540 static int lockd_authenticate(struct svc_rqst *rqstp) 541 { 542 rqstp->rq_client = NULL; 543 switch (rqstp->rq_authop->flavour) { 544 case RPC_AUTH_NULL: 545 case RPC_AUTH_UNIX: 546 if (rqstp->rq_proc == 0) 547 return SVC_OK; 548 if (is_callback(rqstp->rq_proc)) { 549 /* Leave it to individual procedures to 550 * call nlmsvc_lookup_host(rqstp) 551 */ 552 return SVC_OK; 553 } 554 return svc_set_client(rqstp); 555 } 556 return SVC_DENIED; 557 } 558 559 560 param_set_min_max(port, int, simple_strtol, 0, 65535) 561 param_set_min_max(grace_period, unsigned long, simple_strtoul, 562 nlm_grace_period_min, nlm_grace_period_max) 563 param_set_min_max(timeout, unsigned long, simple_strtoul, 564 nlm_timeout_min, nlm_timeout_max) 565 566 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>"); 567 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION "."); 568 MODULE_LICENSE("GPL"); 569 570 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong, 571 &nlm_grace_period, 0644); 572 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong, 573 &nlm_timeout, 0644); 574 module_param_call(nlm_udpport, param_set_port, param_get_int, 575 &nlm_udpport, 0644); 576 module_param_call(nlm_tcpport, param_set_port, param_get_int, 577 &nlm_tcpport, 0644); 578 module_param(nsm_use_hostnames, bool, 0644); 579 module_param(nlm_max_connections, uint, 0644); 580 581 static int lockd_init_net(struct net *net) 582 { 583 struct lockd_net *ln = net_generic(net, lockd_net_id); 584 585 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender); 586 INIT_LIST_HEAD(&ln->grace_list); 587 spin_lock_init(&ln->nsm_clnt_lock); 588 return 0; 589 } 590 591 static void lockd_exit_net(struct net *net) 592 { 593 } 594 595 static struct pernet_operations lockd_net_ops = { 596 .init = lockd_init_net, 597 .exit = lockd_exit_net, 598 .id = &lockd_net_id, 599 .size = sizeof(struct lockd_net), 600 }; 601 602 603 /* 604 * Initialising and terminating the module. 605 */ 606 607 static int __init init_nlm(void) 608 { 609 int err; 610 611 #ifdef CONFIG_SYSCTL 612 err = -ENOMEM; 613 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root); 614 if (nlm_sysctl_table == NULL) 615 goto err_sysctl; 616 #endif 617 err = register_pernet_subsys(&lockd_net_ops); 618 if (err) 619 goto err_pernet; 620 return 0; 621 622 err_pernet: 623 #ifdef CONFIG_SYSCTL 624 unregister_sysctl_table(nlm_sysctl_table); 625 #endif 626 err_sysctl: 627 return err; 628 } 629 630 static void __exit exit_nlm(void) 631 { 632 /* FIXME: delete all NLM clients */ 633 nlm_shutdown_hosts(); 634 unregister_pernet_subsys(&lockd_net_ops); 635 #ifdef CONFIG_SYSCTL 636 unregister_sysctl_table(nlm_sysctl_table); 637 #endif 638 } 639 640 module_init(init_nlm); 641 module_exit(exit_nlm); 642 643 /* 644 * Define NLM program and procedures 645 */ 646 static struct svc_version nlmsvc_version1 = { 647 .vs_vers = 1, 648 .vs_nproc = 17, 649 .vs_proc = nlmsvc_procedures, 650 .vs_xdrsize = NLMSVC_XDRSIZE, 651 }; 652 static struct svc_version nlmsvc_version3 = { 653 .vs_vers = 3, 654 .vs_nproc = 24, 655 .vs_proc = nlmsvc_procedures, 656 .vs_xdrsize = NLMSVC_XDRSIZE, 657 }; 658 #ifdef CONFIG_LOCKD_V4 659 static struct svc_version nlmsvc_version4 = { 660 .vs_vers = 4, 661 .vs_nproc = 24, 662 .vs_proc = nlmsvc_procedures4, 663 .vs_xdrsize = NLMSVC_XDRSIZE, 664 }; 665 #endif 666 static struct svc_version * nlmsvc_version[] = { 667 [1] = &nlmsvc_version1, 668 [3] = &nlmsvc_version3, 669 #ifdef CONFIG_LOCKD_V4 670 [4] = &nlmsvc_version4, 671 #endif 672 }; 673 674 static struct svc_stat nlmsvc_stats; 675 676 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version) 677 static struct svc_program nlmsvc_program = { 678 .pg_prog = NLM_PROGRAM, /* program number */ 679 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */ 680 .pg_vers = nlmsvc_version, /* version table */ 681 .pg_name = "lockd", /* service name */ 682 .pg_class = "nfsd", /* share authentication with nfsd */ 683 .pg_stats = &nlmsvc_stats, /* stats table */ 684 .pg_authenticate = &lockd_authenticate /* export authentication */ 685 }; 686