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 #include "procfs.h" 40 41 #define NLMDBG_FACILITY NLMDBG_SVC 42 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE) 43 #define ALLOWED_SIGS (sigmask(SIGKILL)) 44 45 static struct svc_program nlmsvc_program; 46 47 struct nlmsvc_binding * nlmsvc_ops; 48 EXPORT_SYMBOL_GPL(nlmsvc_ops); 49 50 static DEFINE_MUTEX(nlmsvc_mutex); 51 static unsigned int nlmsvc_users; 52 static struct task_struct *nlmsvc_task; 53 static struct svc_rqst *nlmsvc_rqst; 54 unsigned long nlmsvc_timeout; 55 56 int lockd_net_id; 57 58 /* 59 * These can be set at insmod time (useful for NFS as root filesystem), 60 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003 61 */ 62 static unsigned long nlm_grace_period; 63 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO; 64 static int nlm_udpport, nlm_tcpport; 65 66 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */ 67 static unsigned int nlm_max_connections = 1024; 68 69 /* 70 * Constants needed for the sysctl interface. 71 */ 72 static const unsigned long nlm_grace_period_min = 0; 73 static const unsigned long nlm_grace_period_max = 240; 74 static const unsigned long nlm_timeout_min = 3; 75 static const unsigned long nlm_timeout_max = 20; 76 static const int nlm_port_min = 0, nlm_port_max = 65535; 77 78 #ifdef CONFIG_SYSCTL 79 static struct ctl_table_header * nlm_sysctl_table; 80 #endif 81 82 static unsigned long get_lockd_grace_period(void) 83 { 84 /* Note: nlm_timeout should always be nonzero */ 85 if (nlm_grace_period) 86 return roundup(nlm_grace_period, nlm_timeout) * HZ; 87 else 88 return nlm_timeout * 5 * HZ; 89 } 90 91 static void grace_ender(struct work_struct *grace) 92 { 93 struct delayed_work *dwork = container_of(grace, struct delayed_work, 94 work); 95 struct lockd_net *ln = container_of(dwork, struct lockd_net, 96 grace_period_end); 97 98 locks_end_grace(&ln->lockd_manager); 99 } 100 101 static void set_grace_period(struct net *net) 102 { 103 unsigned long grace_period = get_lockd_grace_period(); 104 struct lockd_net *ln = net_generic(net, lockd_net_id); 105 106 locks_start_grace(net, &ln->lockd_manager); 107 cancel_delayed_work_sync(&ln->grace_period_end); 108 schedule_delayed_work(&ln->grace_period_end, grace_period); 109 } 110 111 static void restart_grace(void) 112 { 113 if (nlmsvc_ops) { 114 struct net *net = &init_net; 115 struct lockd_net *ln = net_generic(net, lockd_net_id); 116 117 cancel_delayed_work_sync(&ln->grace_period_end); 118 locks_end_grace(&ln->lockd_manager); 119 nlmsvc_invalidate_all(); 120 set_grace_period(net); 121 } 122 } 123 124 /* 125 * This is the lockd kernel thread 126 */ 127 static int 128 lockd(void *vrqstp) 129 { 130 int err = 0; 131 struct svc_rqst *rqstp = vrqstp; 132 133 /* try_to_freeze() is called from svc_recv() */ 134 set_freezable(); 135 136 /* Allow SIGKILL to tell lockd to drop all of its locks */ 137 allow_signal(SIGKILL); 138 139 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n"); 140 141 /* 142 * The main request loop. We don't terminate until the last 143 * NFS mount or NFS daemon has gone away. 144 */ 145 while (!kthread_should_stop()) { 146 long timeout = MAX_SCHEDULE_TIMEOUT; 147 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]); 148 149 /* update sv_maxconn if it has changed */ 150 rqstp->rq_server->sv_maxconn = nlm_max_connections; 151 152 if (signalled()) { 153 flush_signals(current); 154 restart_grace(); 155 continue; 156 } 157 158 timeout = nlmsvc_retry_blocked(); 159 160 /* 161 * Find a socket with data available and call its 162 * recvfrom routine. 163 */ 164 err = svc_recv(rqstp, timeout); 165 if (err == -EAGAIN || err == -EINTR) 166 continue; 167 dprintk("lockd: request from %s\n", 168 svc_print_addr(rqstp, buf, sizeof(buf))); 169 170 svc_process(rqstp); 171 } 172 flush_signals(current); 173 if (nlmsvc_ops) 174 nlmsvc_invalidate_all(); 175 nlm_shutdown_hosts(); 176 return 0; 177 } 178 179 static int create_lockd_listener(struct svc_serv *serv, const char *name, 180 struct net *net, const int family, 181 const unsigned short port) 182 { 183 struct svc_xprt *xprt; 184 185 xprt = svc_find_xprt(serv, name, net, family, 0); 186 if (xprt == NULL) 187 return svc_create_xprt(serv, name, net, family, port, 188 SVC_SOCK_DEFAULTS); 189 svc_xprt_put(xprt); 190 return 0; 191 } 192 193 static int create_lockd_family(struct svc_serv *serv, struct net *net, 194 const int family) 195 { 196 int err; 197 198 err = create_lockd_listener(serv, "udp", net, family, nlm_udpport); 199 if (err < 0) 200 return err; 201 202 return create_lockd_listener(serv, "tcp", net, family, nlm_tcpport); 203 } 204 205 /* 206 * Ensure there are active UDP and TCP listeners for lockd. 207 * 208 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some 209 * local services (such as rpc.statd) still require UDP, and 210 * some NFS servers do not yet support NLM over TCP. 211 * 212 * Returns zero if all listeners are available; otherwise a 213 * negative errno value is returned. 214 */ 215 static int make_socks(struct svc_serv *serv, struct net *net) 216 { 217 static int warned; 218 int err; 219 220 err = create_lockd_family(serv, net, PF_INET); 221 if (err < 0) 222 goto out_err; 223 224 err = create_lockd_family(serv, net, PF_INET6); 225 if (err < 0 && err != -EAFNOSUPPORT) 226 goto out_err; 227 228 warned = 0; 229 return 0; 230 231 out_err: 232 if (warned++ == 0) 233 printk(KERN_WARNING 234 "lockd_up: makesock failed, error=%d\n", err); 235 svc_shutdown_net(serv, net); 236 return err; 237 } 238 239 static int lockd_up_net(struct svc_serv *serv, struct net *net) 240 { 241 struct lockd_net *ln = net_generic(net, lockd_net_id); 242 int error; 243 244 if (ln->nlmsvc_users++) 245 return 0; 246 247 error = svc_bind(serv, net); 248 if (error) 249 goto err_bind; 250 251 error = make_socks(serv, net); 252 if (error < 0) 253 goto err_bind; 254 set_grace_period(net); 255 dprintk("lockd_up_net: per-net data created; net=%p\n", net); 256 return 0; 257 258 err_bind: 259 ln->nlmsvc_users--; 260 return error; 261 } 262 263 static void lockd_down_net(struct svc_serv *serv, struct net *net) 264 { 265 struct lockd_net *ln = net_generic(net, lockd_net_id); 266 267 if (ln->nlmsvc_users) { 268 if (--ln->nlmsvc_users == 0) { 269 nlm_shutdown_hosts_net(net); 270 cancel_delayed_work_sync(&ln->grace_period_end); 271 locks_end_grace(&ln->lockd_manager); 272 svc_shutdown_net(serv, net); 273 dprintk("lockd_down_net: per-net data destroyed; net=%p\n", net); 274 } 275 } else { 276 printk(KERN_ERR "lockd_down_net: no users! task=%p, net=%p\n", 277 nlmsvc_task, net); 278 BUG(); 279 } 280 } 281 282 static int lockd_start_svc(struct svc_serv *serv) 283 { 284 int error; 285 286 if (nlmsvc_rqst) 287 return 0; 288 289 /* 290 * Create the kernel thread and wait for it to start. 291 */ 292 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE); 293 if (IS_ERR(nlmsvc_rqst)) { 294 error = PTR_ERR(nlmsvc_rqst); 295 printk(KERN_WARNING 296 "lockd_up: svc_rqst allocation failed, error=%d\n", 297 error); 298 goto out_rqst; 299 } 300 301 svc_sock_update_bufs(serv); 302 serv->sv_maxconn = nlm_max_connections; 303 304 nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name); 305 if (IS_ERR(nlmsvc_task)) { 306 error = PTR_ERR(nlmsvc_task); 307 printk(KERN_WARNING 308 "lockd_up: kthread_run failed, error=%d\n", error); 309 goto out_task; 310 } 311 nlmsvc_rqst->rq_task = nlmsvc_task; 312 wake_up_process(nlmsvc_task); 313 314 dprintk("lockd_up: service started\n"); 315 return 0; 316 317 out_task: 318 svc_exit_thread(nlmsvc_rqst); 319 nlmsvc_task = NULL; 320 out_rqst: 321 nlmsvc_rqst = NULL; 322 return error; 323 } 324 325 static struct svc_serv *lockd_create_svc(void) 326 { 327 struct svc_serv *serv; 328 329 /* 330 * Check whether we're already up and running. 331 */ 332 if (nlmsvc_rqst) { 333 /* 334 * Note: increase service usage, because later in case of error 335 * svc_destroy() will be called. 336 */ 337 svc_get(nlmsvc_rqst->rq_server); 338 return nlmsvc_rqst->rq_server; 339 } 340 341 /* 342 * Sanity check: if there's no pid, 343 * we should be the first user ... 344 */ 345 if (nlmsvc_users) 346 printk(KERN_WARNING 347 "lockd_up: no pid, %d users??\n", nlmsvc_users); 348 349 if (!nlm_timeout) 350 nlm_timeout = LOCKD_DFLT_TIMEO; 351 nlmsvc_timeout = nlm_timeout * HZ; 352 353 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, svc_rpcb_cleanup); 354 if (!serv) { 355 printk(KERN_WARNING "lockd_up: create service failed\n"); 356 return ERR_PTR(-ENOMEM); 357 } 358 dprintk("lockd_up: service created\n"); 359 return serv; 360 } 361 362 /* 363 * Bring up the lockd process if it's not already up. 364 */ 365 int lockd_up(struct net *net) 366 { 367 struct svc_serv *serv; 368 int error; 369 370 mutex_lock(&nlmsvc_mutex); 371 372 serv = lockd_create_svc(); 373 if (IS_ERR(serv)) { 374 error = PTR_ERR(serv); 375 goto err_create; 376 } 377 378 error = lockd_up_net(serv, net); 379 if (error < 0) 380 goto err_net; 381 382 error = lockd_start_svc(serv); 383 if (error < 0) 384 goto err_start; 385 386 nlmsvc_users++; 387 /* 388 * Note: svc_serv structures have an initial use count of 1, 389 * so we exit through here on both success and failure. 390 */ 391 err_net: 392 svc_destroy(serv); 393 err_create: 394 mutex_unlock(&nlmsvc_mutex); 395 return error; 396 397 err_start: 398 lockd_down_net(serv, net); 399 goto err_net; 400 } 401 EXPORT_SYMBOL_GPL(lockd_up); 402 403 /* 404 * Decrement the user count and bring down lockd if we're the last. 405 */ 406 void 407 lockd_down(struct net *net) 408 { 409 mutex_lock(&nlmsvc_mutex); 410 lockd_down_net(nlmsvc_rqst->rq_server, net); 411 if (nlmsvc_users) { 412 if (--nlmsvc_users) 413 goto out; 414 } else { 415 printk(KERN_ERR "lockd_down: no users! task=%p\n", 416 nlmsvc_task); 417 BUG(); 418 } 419 420 if (!nlmsvc_task) { 421 printk(KERN_ERR "lockd_down: no lockd running.\n"); 422 BUG(); 423 } 424 kthread_stop(nlmsvc_task); 425 dprintk("lockd_down: service stopped\n"); 426 svc_exit_thread(nlmsvc_rqst); 427 dprintk("lockd_down: service destroyed\n"); 428 nlmsvc_task = NULL; 429 nlmsvc_rqst = NULL; 430 out: 431 mutex_unlock(&nlmsvc_mutex); 432 } 433 EXPORT_SYMBOL_GPL(lockd_down); 434 435 #ifdef CONFIG_SYSCTL 436 437 /* 438 * Sysctl parameters (same as module parameters, different interface). 439 */ 440 441 static struct ctl_table nlm_sysctls[] = { 442 { 443 .procname = "nlm_grace_period", 444 .data = &nlm_grace_period, 445 .maxlen = sizeof(unsigned long), 446 .mode = 0644, 447 .proc_handler = proc_doulongvec_minmax, 448 .extra1 = (unsigned long *) &nlm_grace_period_min, 449 .extra2 = (unsigned long *) &nlm_grace_period_max, 450 }, 451 { 452 .procname = "nlm_timeout", 453 .data = &nlm_timeout, 454 .maxlen = sizeof(unsigned long), 455 .mode = 0644, 456 .proc_handler = proc_doulongvec_minmax, 457 .extra1 = (unsigned long *) &nlm_timeout_min, 458 .extra2 = (unsigned long *) &nlm_timeout_max, 459 }, 460 { 461 .procname = "nlm_udpport", 462 .data = &nlm_udpport, 463 .maxlen = sizeof(int), 464 .mode = 0644, 465 .proc_handler = proc_dointvec_minmax, 466 .extra1 = (int *) &nlm_port_min, 467 .extra2 = (int *) &nlm_port_max, 468 }, 469 { 470 .procname = "nlm_tcpport", 471 .data = &nlm_tcpport, 472 .maxlen = sizeof(int), 473 .mode = 0644, 474 .proc_handler = proc_dointvec_minmax, 475 .extra1 = (int *) &nlm_port_min, 476 .extra2 = (int *) &nlm_port_max, 477 }, 478 { 479 .procname = "nsm_use_hostnames", 480 .data = &nsm_use_hostnames, 481 .maxlen = sizeof(int), 482 .mode = 0644, 483 .proc_handler = proc_dointvec, 484 }, 485 { 486 .procname = "nsm_local_state", 487 .data = &nsm_local_state, 488 .maxlen = sizeof(int), 489 .mode = 0644, 490 .proc_handler = proc_dointvec, 491 }, 492 { } 493 }; 494 495 static struct ctl_table nlm_sysctl_dir[] = { 496 { 497 .procname = "nfs", 498 .mode = 0555, 499 .child = nlm_sysctls, 500 }, 501 { } 502 }; 503 504 static struct ctl_table nlm_sysctl_root[] = { 505 { 506 .procname = "fs", 507 .mode = 0555, 508 .child = nlm_sysctl_dir, 509 }, 510 { } 511 }; 512 513 #endif /* CONFIG_SYSCTL */ 514 515 /* 516 * Module (and sysfs) parameters. 517 */ 518 519 #define param_set_min_max(name, type, which_strtol, min, max) \ 520 static int param_set_##name(const char *val, struct kernel_param *kp) \ 521 { \ 522 char *endp; \ 523 __typeof__(type) num = which_strtol(val, &endp, 0); \ 524 if (endp == val || *endp || num < (min) || num > (max)) \ 525 return -EINVAL; \ 526 *((type *) kp->arg) = num; \ 527 return 0; \ 528 } 529 530 static inline int is_callback(u32 proc) 531 { 532 return proc == NLMPROC_GRANTED 533 || proc == NLMPROC_GRANTED_MSG 534 || proc == NLMPROC_TEST_RES 535 || proc == NLMPROC_LOCK_RES 536 || proc == NLMPROC_CANCEL_RES 537 || proc == NLMPROC_UNLOCK_RES 538 || proc == NLMPROC_NSM_NOTIFY; 539 } 540 541 542 static int lockd_authenticate(struct svc_rqst *rqstp) 543 { 544 rqstp->rq_client = NULL; 545 switch (rqstp->rq_authop->flavour) { 546 case RPC_AUTH_NULL: 547 case RPC_AUTH_UNIX: 548 if (rqstp->rq_proc == 0) 549 return SVC_OK; 550 if (is_callback(rqstp->rq_proc)) { 551 /* Leave it to individual procedures to 552 * call nlmsvc_lookup_host(rqstp) 553 */ 554 return SVC_OK; 555 } 556 return svc_set_client(rqstp); 557 } 558 return SVC_DENIED; 559 } 560 561 562 param_set_min_max(port, int, simple_strtol, 0, 65535) 563 param_set_min_max(grace_period, unsigned long, simple_strtoul, 564 nlm_grace_period_min, nlm_grace_period_max) 565 param_set_min_max(timeout, unsigned long, simple_strtoul, 566 nlm_timeout_min, nlm_timeout_max) 567 568 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>"); 569 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION "."); 570 MODULE_LICENSE("GPL"); 571 572 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong, 573 &nlm_grace_period, 0644); 574 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong, 575 &nlm_timeout, 0644); 576 module_param_call(nlm_udpport, param_set_port, param_get_int, 577 &nlm_udpport, 0644); 578 module_param_call(nlm_tcpport, param_set_port, param_get_int, 579 &nlm_tcpport, 0644); 580 module_param(nsm_use_hostnames, bool, 0644); 581 module_param(nlm_max_connections, uint, 0644); 582 583 static int lockd_init_net(struct net *net) 584 { 585 struct lockd_net *ln = net_generic(net, lockd_net_id); 586 587 INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender); 588 INIT_LIST_HEAD(&ln->lockd_manager.list); 589 spin_lock_init(&ln->nsm_clnt_lock); 590 return 0; 591 } 592 593 static void lockd_exit_net(struct net *net) 594 { 595 } 596 597 static struct pernet_operations lockd_net_ops = { 598 .init = lockd_init_net, 599 .exit = lockd_exit_net, 600 .id = &lockd_net_id, 601 .size = sizeof(struct lockd_net), 602 }; 603 604 605 /* 606 * Initialising and terminating the module. 607 */ 608 609 static int __init init_nlm(void) 610 { 611 int err; 612 613 #ifdef CONFIG_SYSCTL 614 err = -ENOMEM; 615 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root); 616 if (nlm_sysctl_table == NULL) 617 goto err_sysctl; 618 #endif 619 err = register_pernet_subsys(&lockd_net_ops); 620 if (err) 621 goto err_pernet; 622 623 err = lockd_create_procfs(); 624 if (err) 625 goto err_procfs; 626 627 return 0; 628 629 err_procfs: 630 unregister_pernet_subsys(&lockd_net_ops); 631 err_pernet: 632 #ifdef CONFIG_SYSCTL 633 unregister_sysctl_table(nlm_sysctl_table); 634 err_sysctl: 635 #endif 636 return err; 637 } 638 639 static void __exit exit_nlm(void) 640 { 641 /* FIXME: delete all NLM clients */ 642 nlm_shutdown_hosts(); 643 lockd_remove_procfs(); 644 unregister_pernet_subsys(&lockd_net_ops); 645 #ifdef CONFIG_SYSCTL 646 unregister_sysctl_table(nlm_sysctl_table); 647 #endif 648 } 649 650 module_init(init_nlm); 651 module_exit(exit_nlm); 652 653 /* 654 * Define NLM program and procedures 655 */ 656 static struct svc_version nlmsvc_version1 = { 657 .vs_vers = 1, 658 .vs_nproc = 17, 659 .vs_proc = nlmsvc_procedures, 660 .vs_xdrsize = NLMSVC_XDRSIZE, 661 }; 662 static struct svc_version nlmsvc_version3 = { 663 .vs_vers = 3, 664 .vs_nproc = 24, 665 .vs_proc = nlmsvc_procedures, 666 .vs_xdrsize = NLMSVC_XDRSIZE, 667 }; 668 #ifdef CONFIG_LOCKD_V4 669 static struct svc_version nlmsvc_version4 = { 670 .vs_vers = 4, 671 .vs_nproc = 24, 672 .vs_proc = nlmsvc_procedures4, 673 .vs_xdrsize = NLMSVC_XDRSIZE, 674 }; 675 #endif 676 static struct svc_version * nlmsvc_version[] = { 677 [1] = &nlmsvc_version1, 678 [3] = &nlmsvc_version3, 679 #ifdef CONFIG_LOCKD_V4 680 [4] = &nlmsvc_version4, 681 #endif 682 }; 683 684 static struct svc_stat nlmsvc_stats; 685 686 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version) 687 static struct svc_program nlmsvc_program = { 688 .pg_prog = NLM_PROGRAM, /* program number */ 689 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */ 690 .pg_vers = nlmsvc_version, /* version table */ 691 .pg_name = "lockd", /* service name */ 692 .pg_class = "nfsd", /* share authentication with nfsd */ 693 .pg_stats = &nlmsvc_stats, /* stats table */ 694 .pg_authenticate = &lockd_authenticate /* export authentication */ 695 }; 696