1 /* 2 * linux/net/sunrpc/svc.c 3 * 4 * High-level RPC service routines 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 7 * 8 * Multiple threads pools and NUMAisation 9 * Copyright (c) 2006 Silicon Graphics, Inc. 10 * by Greg Banks <gnb@melbourne.sgi.com> 11 */ 12 13 #include <linux/linkage.h> 14 #include <linux/sched.h> 15 #include <linux/errno.h> 16 #include <linux/net.h> 17 #include <linux/in.h> 18 #include <linux/mm.h> 19 #include <linux/interrupt.h> 20 #include <linux/module.h> 21 #include <linux/kthread.h> 22 23 #include <linux/sunrpc/types.h> 24 #include <linux/sunrpc/xdr.h> 25 #include <linux/sunrpc/stats.h> 26 #include <linux/sunrpc/svcsock.h> 27 #include <linux/sunrpc/clnt.h> 28 29 #define RPCDBG_FACILITY RPCDBG_SVCDSP 30 31 static void svc_unregister(const struct svc_serv *serv); 32 33 #define svc_serv_is_pooled(serv) ((serv)->sv_function) 34 35 /* 36 * Mode for mapping cpus to pools. 37 */ 38 enum { 39 SVC_POOL_AUTO = -1, /* choose one of the others */ 40 SVC_POOL_GLOBAL, /* no mapping, just a single global pool 41 * (legacy & UP mode) */ 42 SVC_POOL_PERCPU, /* one pool per cpu */ 43 SVC_POOL_PERNODE /* one pool per numa node */ 44 }; 45 #define SVC_POOL_DEFAULT SVC_POOL_GLOBAL 46 47 /* 48 * Structure for mapping cpus to pools and vice versa. 49 * Setup once during sunrpc initialisation. 50 */ 51 static struct svc_pool_map { 52 int count; /* How many svc_servs use us */ 53 int mode; /* Note: int not enum to avoid 54 * warnings about "enumeration value 55 * not handled in switch" */ 56 unsigned int npools; 57 unsigned int *pool_to; /* maps pool id to cpu or node */ 58 unsigned int *to_pool; /* maps cpu or node to pool id */ 59 } svc_pool_map = { 60 .count = 0, 61 .mode = SVC_POOL_DEFAULT 62 }; 63 static DEFINE_MUTEX(svc_pool_map_mutex);/* protects svc_pool_map.count only */ 64 65 static int 66 param_set_pool_mode(const char *val, struct kernel_param *kp) 67 { 68 int *ip = (int *)kp->arg; 69 struct svc_pool_map *m = &svc_pool_map; 70 int err; 71 72 mutex_lock(&svc_pool_map_mutex); 73 74 err = -EBUSY; 75 if (m->count) 76 goto out; 77 78 err = 0; 79 if (!strncmp(val, "auto", 4)) 80 *ip = SVC_POOL_AUTO; 81 else if (!strncmp(val, "global", 6)) 82 *ip = SVC_POOL_GLOBAL; 83 else if (!strncmp(val, "percpu", 6)) 84 *ip = SVC_POOL_PERCPU; 85 else if (!strncmp(val, "pernode", 7)) 86 *ip = SVC_POOL_PERNODE; 87 else 88 err = -EINVAL; 89 90 out: 91 mutex_unlock(&svc_pool_map_mutex); 92 return err; 93 } 94 95 static int 96 param_get_pool_mode(char *buf, struct kernel_param *kp) 97 { 98 int *ip = (int *)kp->arg; 99 100 switch (*ip) 101 { 102 case SVC_POOL_AUTO: 103 return strlcpy(buf, "auto", 20); 104 case SVC_POOL_GLOBAL: 105 return strlcpy(buf, "global", 20); 106 case SVC_POOL_PERCPU: 107 return strlcpy(buf, "percpu", 20); 108 case SVC_POOL_PERNODE: 109 return strlcpy(buf, "pernode", 20); 110 default: 111 return sprintf(buf, "%d", *ip); 112 } 113 } 114 115 module_param_call(pool_mode, param_set_pool_mode, param_get_pool_mode, 116 &svc_pool_map.mode, 0644); 117 118 /* 119 * Detect best pool mapping mode heuristically, 120 * according to the machine's topology. 121 */ 122 static int 123 svc_pool_map_choose_mode(void) 124 { 125 unsigned int node; 126 127 if (num_online_nodes() > 1) { 128 /* 129 * Actually have multiple NUMA nodes, 130 * so split pools on NUMA node boundaries 131 */ 132 return SVC_POOL_PERNODE; 133 } 134 135 node = any_online_node(node_online_map); 136 if (nr_cpus_node(node) > 2) { 137 /* 138 * Non-trivial SMP, or CONFIG_NUMA on 139 * non-NUMA hardware, e.g. with a generic 140 * x86_64 kernel on Xeons. In this case we 141 * want to divide the pools on cpu boundaries. 142 */ 143 return SVC_POOL_PERCPU; 144 } 145 146 /* default: one global pool */ 147 return SVC_POOL_GLOBAL; 148 } 149 150 /* 151 * Allocate the to_pool[] and pool_to[] arrays. 152 * Returns 0 on success or an errno. 153 */ 154 static int 155 svc_pool_map_alloc_arrays(struct svc_pool_map *m, unsigned int maxpools) 156 { 157 m->to_pool = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL); 158 if (!m->to_pool) 159 goto fail; 160 m->pool_to = kcalloc(maxpools, sizeof(unsigned int), GFP_KERNEL); 161 if (!m->pool_to) 162 goto fail_free; 163 164 return 0; 165 166 fail_free: 167 kfree(m->to_pool); 168 fail: 169 return -ENOMEM; 170 } 171 172 /* 173 * Initialise the pool map for SVC_POOL_PERCPU mode. 174 * Returns number of pools or <0 on error. 175 */ 176 static int 177 svc_pool_map_init_percpu(struct svc_pool_map *m) 178 { 179 unsigned int maxpools = nr_cpu_ids; 180 unsigned int pidx = 0; 181 unsigned int cpu; 182 int err; 183 184 err = svc_pool_map_alloc_arrays(m, maxpools); 185 if (err) 186 return err; 187 188 for_each_online_cpu(cpu) { 189 BUG_ON(pidx > maxpools); 190 m->to_pool[cpu] = pidx; 191 m->pool_to[pidx] = cpu; 192 pidx++; 193 } 194 /* cpus brought online later all get mapped to pool0, sorry */ 195 196 return pidx; 197 }; 198 199 200 /* 201 * Initialise the pool map for SVC_POOL_PERNODE mode. 202 * Returns number of pools or <0 on error. 203 */ 204 static int 205 svc_pool_map_init_pernode(struct svc_pool_map *m) 206 { 207 unsigned int maxpools = nr_node_ids; 208 unsigned int pidx = 0; 209 unsigned int node; 210 int err; 211 212 err = svc_pool_map_alloc_arrays(m, maxpools); 213 if (err) 214 return err; 215 216 for_each_node_with_cpus(node) { 217 /* some architectures (e.g. SN2) have cpuless nodes */ 218 BUG_ON(pidx > maxpools); 219 m->to_pool[node] = pidx; 220 m->pool_to[pidx] = node; 221 pidx++; 222 } 223 /* nodes brought online later all get mapped to pool0, sorry */ 224 225 return pidx; 226 } 227 228 229 /* 230 * Add a reference to the global map of cpus to pools (and 231 * vice versa). Initialise the map if we're the first user. 232 * Returns the number of pools. 233 */ 234 static unsigned int 235 svc_pool_map_get(void) 236 { 237 struct svc_pool_map *m = &svc_pool_map; 238 int npools = -1; 239 240 mutex_lock(&svc_pool_map_mutex); 241 242 if (m->count++) { 243 mutex_unlock(&svc_pool_map_mutex); 244 return m->npools; 245 } 246 247 if (m->mode == SVC_POOL_AUTO) 248 m->mode = svc_pool_map_choose_mode(); 249 250 switch (m->mode) { 251 case SVC_POOL_PERCPU: 252 npools = svc_pool_map_init_percpu(m); 253 break; 254 case SVC_POOL_PERNODE: 255 npools = svc_pool_map_init_pernode(m); 256 break; 257 } 258 259 if (npools < 0) { 260 /* default, or memory allocation failure */ 261 npools = 1; 262 m->mode = SVC_POOL_GLOBAL; 263 } 264 m->npools = npools; 265 266 mutex_unlock(&svc_pool_map_mutex); 267 return m->npools; 268 } 269 270 271 /* 272 * Drop a reference to the global map of cpus to pools. 273 * When the last reference is dropped, the map data is 274 * freed; this allows the sysadmin to change the pool 275 * mode using the pool_mode module option without 276 * rebooting or re-loading sunrpc.ko. 277 */ 278 static void 279 svc_pool_map_put(void) 280 { 281 struct svc_pool_map *m = &svc_pool_map; 282 283 mutex_lock(&svc_pool_map_mutex); 284 285 if (!--m->count) { 286 m->mode = SVC_POOL_DEFAULT; 287 kfree(m->to_pool); 288 kfree(m->pool_to); 289 m->npools = 0; 290 } 291 292 mutex_unlock(&svc_pool_map_mutex); 293 } 294 295 296 /* 297 * Set the given thread's cpus_allowed mask so that it 298 * will only run on cpus in the given pool. 299 */ 300 static inline void 301 svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx) 302 { 303 struct svc_pool_map *m = &svc_pool_map; 304 unsigned int node = m->pool_to[pidx]; 305 306 /* 307 * The caller checks for sv_nrpools > 1, which 308 * implies that we've been initialized. 309 */ 310 BUG_ON(m->count == 0); 311 312 switch (m->mode) { 313 case SVC_POOL_PERCPU: 314 { 315 set_cpus_allowed_ptr(task, cpumask_of(node)); 316 break; 317 } 318 case SVC_POOL_PERNODE: 319 { 320 set_cpus_allowed_ptr(task, cpumask_of_node(node)); 321 break; 322 } 323 } 324 } 325 326 /* 327 * Use the mapping mode to choose a pool for a given CPU. 328 * Used when enqueueing an incoming RPC. Always returns 329 * a non-NULL pool pointer. 330 */ 331 struct svc_pool * 332 svc_pool_for_cpu(struct svc_serv *serv, int cpu) 333 { 334 struct svc_pool_map *m = &svc_pool_map; 335 unsigned int pidx = 0; 336 337 /* 338 * An uninitialised map happens in a pure client when 339 * lockd is brought up, so silently treat it the 340 * same as SVC_POOL_GLOBAL. 341 */ 342 if (svc_serv_is_pooled(serv)) { 343 switch (m->mode) { 344 case SVC_POOL_PERCPU: 345 pidx = m->to_pool[cpu]; 346 break; 347 case SVC_POOL_PERNODE: 348 pidx = m->to_pool[cpu_to_node(cpu)]; 349 break; 350 } 351 } 352 return &serv->sv_pools[pidx % serv->sv_nrpools]; 353 } 354 355 356 /* 357 * Create an RPC service 358 */ 359 static struct svc_serv * 360 __svc_create(struct svc_program *prog, unsigned int bufsize, int npools, 361 void (*shutdown)(struct svc_serv *serv)) 362 { 363 struct svc_serv *serv; 364 unsigned int vers; 365 unsigned int xdrsize; 366 unsigned int i; 367 368 if (!(serv = kzalloc(sizeof(*serv), GFP_KERNEL))) 369 return NULL; 370 serv->sv_name = prog->pg_name; 371 serv->sv_program = prog; 372 serv->sv_nrthreads = 1; 373 serv->sv_stats = prog->pg_stats; 374 if (bufsize > RPCSVC_MAXPAYLOAD) 375 bufsize = RPCSVC_MAXPAYLOAD; 376 serv->sv_max_payload = bufsize? bufsize : 4096; 377 serv->sv_max_mesg = roundup(serv->sv_max_payload + PAGE_SIZE, PAGE_SIZE); 378 serv->sv_shutdown = shutdown; 379 xdrsize = 0; 380 while (prog) { 381 prog->pg_lovers = prog->pg_nvers-1; 382 for (vers=0; vers<prog->pg_nvers ; vers++) 383 if (prog->pg_vers[vers]) { 384 prog->pg_hivers = vers; 385 if (prog->pg_lovers > vers) 386 prog->pg_lovers = vers; 387 if (prog->pg_vers[vers]->vs_xdrsize > xdrsize) 388 xdrsize = prog->pg_vers[vers]->vs_xdrsize; 389 } 390 prog = prog->pg_next; 391 } 392 serv->sv_xdrsize = xdrsize; 393 INIT_LIST_HEAD(&serv->sv_tempsocks); 394 INIT_LIST_HEAD(&serv->sv_permsocks); 395 init_timer(&serv->sv_temptimer); 396 spin_lock_init(&serv->sv_lock); 397 398 serv->sv_nrpools = npools; 399 serv->sv_pools = 400 kcalloc(serv->sv_nrpools, sizeof(struct svc_pool), 401 GFP_KERNEL); 402 if (!serv->sv_pools) { 403 kfree(serv); 404 return NULL; 405 } 406 407 for (i = 0; i < serv->sv_nrpools; i++) { 408 struct svc_pool *pool = &serv->sv_pools[i]; 409 410 dprintk("svc: initialising pool %u for %s\n", 411 i, serv->sv_name); 412 413 pool->sp_id = i; 414 INIT_LIST_HEAD(&pool->sp_threads); 415 INIT_LIST_HEAD(&pool->sp_sockets); 416 INIT_LIST_HEAD(&pool->sp_all_threads); 417 spin_lock_init(&pool->sp_lock); 418 } 419 420 /* Remove any stale portmap registrations */ 421 svc_unregister(serv); 422 423 return serv; 424 } 425 426 struct svc_serv * 427 svc_create(struct svc_program *prog, unsigned int bufsize, 428 void (*shutdown)(struct svc_serv *serv)) 429 { 430 return __svc_create(prog, bufsize, /*npools*/1, shutdown); 431 } 432 EXPORT_SYMBOL_GPL(svc_create); 433 434 struct svc_serv * 435 svc_create_pooled(struct svc_program *prog, unsigned int bufsize, 436 void (*shutdown)(struct svc_serv *serv), 437 svc_thread_fn func, struct module *mod) 438 { 439 struct svc_serv *serv; 440 unsigned int npools = svc_pool_map_get(); 441 442 serv = __svc_create(prog, bufsize, npools, shutdown); 443 444 if (serv != NULL) { 445 serv->sv_function = func; 446 serv->sv_module = mod; 447 } 448 449 return serv; 450 } 451 EXPORT_SYMBOL_GPL(svc_create_pooled); 452 453 /* 454 * Destroy an RPC service. Should be called with appropriate locking to 455 * protect the sv_nrthreads, sv_permsocks and sv_tempsocks. 456 */ 457 void 458 svc_destroy(struct svc_serv *serv) 459 { 460 dprintk("svc: svc_destroy(%s, %d)\n", 461 serv->sv_program->pg_name, 462 serv->sv_nrthreads); 463 464 if (serv->sv_nrthreads) { 465 if (--(serv->sv_nrthreads) != 0) { 466 svc_sock_update_bufs(serv); 467 return; 468 } 469 } else 470 printk("svc_destroy: no threads for serv=%p!\n", serv); 471 472 del_timer_sync(&serv->sv_temptimer); 473 474 svc_close_all(&serv->sv_tempsocks); 475 476 if (serv->sv_shutdown) 477 serv->sv_shutdown(serv); 478 479 svc_close_all(&serv->sv_permsocks); 480 481 BUG_ON(!list_empty(&serv->sv_permsocks)); 482 BUG_ON(!list_empty(&serv->sv_tempsocks)); 483 484 cache_clean_deferred(serv); 485 486 if (svc_serv_is_pooled(serv)) 487 svc_pool_map_put(); 488 489 svc_unregister(serv); 490 kfree(serv->sv_pools); 491 kfree(serv); 492 } 493 EXPORT_SYMBOL_GPL(svc_destroy); 494 495 /* 496 * Allocate an RPC server's buffer space. 497 * We allocate pages and place them in rq_argpages. 498 */ 499 static int 500 svc_init_buffer(struct svc_rqst *rqstp, unsigned int size) 501 { 502 unsigned int pages, arghi; 503 504 pages = size / PAGE_SIZE + 1; /* extra page as we hold both request and reply. 505 * We assume one is at most one page 506 */ 507 arghi = 0; 508 BUG_ON(pages > RPCSVC_MAXPAGES); 509 while (pages) { 510 struct page *p = alloc_page(GFP_KERNEL); 511 if (!p) 512 break; 513 rqstp->rq_pages[arghi++] = p; 514 pages--; 515 } 516 return pages == 0; 517 } 518 519 /* 520 * Release an RPC server buffer 521 */ 522 static void 523 svc_release_buffer(struct svc_rqst *rqstp) 524 { 525 unsigned int i; 526 527 for (i = 0; i < ARRAY_SIZE(rqstp->rq_pages); i++) 528 if (rqstp->rq_pages[i]) 529 put_page(rqstp->rq_pages[i]); 530 } 531 532 struct svc_rqst * 533 svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool) 534 { 535 struct svc_rqst *rqstp; 536 537 rqstp = kzalloc(sizeof(*rqstp), GFP_KERNEL); 538 if (!rqstp) 539 goto out_enomem; 540 541 init_waitqueue_head(&rqstp->rq_wait); 542 543 serv->sv_nrthreads++; 544 spin_lock_bh(&pool->sp_lock); 545 pool->sp_nrthreads++; 546 list_add(&rqstp->rq_all, &pool->sp_all_threads); 547 spin_unlock_bh(&pool->sp_lock); 548 rqstp->rq_server = serv; 549 rqstp->rq_pool = pool; 550 551 rqstp->rq_argp = kmalloc(serv->sv_xdrsize, GFP_KERNEL); 552 if (!rqstp->rq_argp) 553 goto out_thread; 554 555 rqstp->rq_resp = kmalloc(serv->sv_xdrsize, GFP_KERNEL); 556 if (!rqstp->rq_resp) 557 goto out_thread; 558 559 if (!svc_init_buffer(rqstp, serv->sv_max_mesg)) 560 goto out_thread; 561 562 return rqstp; 563 out_thread: 564 svc_exit_thread(rqstp); 565 out_enomem: 566 return ERR_PTR(-ENOMEM); 567 } 568 EXPORT_SYMBOL_GPL(svc_prepare_thread); 569 570 /* 571 * Choose a pool in which to create a new thread, for svc_set_num_threads 572 */ 573 static inline struct svc_pool * 574 choose_pool(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state) 575 { 576 if (pool != NULL) 577 return pool; 578 579 return &serv->sv_pools[(*state)++ % serv->sv_nrpools]; 580 } 581 582 /* 583 * Choose a thread to kill, for svc_set_num_threads 584 */ 585 static inline struct task_struct * 586 choose_victim(struct svc_serv *serv, struct svc_pool *pool, unsigned int *state) 587 { 588 unsigned int i; 589 struct task_struct *task = NULL; 590 591 if (pool != NULL) { 592 spin_lock_bh(&pool->sp_lock); 593 } else { 594 /* choose a pool in round-robin fashion */ 595 for (i = 0; i < serv->sv_nrpools; i++) { 596 pool = &serv->sv_pools[--(*state) % serv->sv_nrpools]; 597 spin_lock_bh(&pool->sp_lock); 598 if (!list_empty(&pool->sp_all_threads)) 599 goto found_pool; 600 spin_unlock_bh(&pool->sp_lock); 601 } 602 return NULL; 603 } 604 605 found_pool: 606 if (!list_empty(&pool->sp_all_threads)) { 607 struct svc_rqst *rqstp; 608 609 /* 610 * Remove from the pool->sp_all_threads list 611 * so we don't try to kill it again. 612 */ 613 rqstp = list_entry(pool->sp_all_threads.next, struct svc_rqst, rq_all); 614 list_del_init(&rqstp->rq_all); 615 task = rqstp->rq_task; 616 } 617 spin_unlock_bh(&pool->sp_lock); 618 619 return task; 620 } 621 622 /* 623 * Create or destroy enough new threads to make the number 624 * of threads the given number. If `pool' is non-NULL, applies 625 * only to threads in that pool, otherwise round-robins between 626 * all pools. Must be called with a svc_get() reference and 627 * the BKL or another lock to protect access to svc_serv fields. 628 * 629 * Destroying threads relies on the service threads filling in 630 * rqstp->rq_task, which only the nfs ones do. Assumes the serv 631 * has been created using svc_create_pooled(). 632 * 633 * Based on code that used to be in nfsd_svc() but tweaked 634 * to be pool-aware. 635 */ 636 int 637 svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs) 638 { 639 struct svc_rqst *rqstp; 640 struct task_struct *task; 641 struct svc_pool *chosen_pool; 642 int error = 0; 643 unsigned int state = serv->sv_nrthreads-1; 644 645 if (pool == NULL) { 646 /* The -1 assumes caller has done a svc_get() */ 647 nrservs -= (serv->sv_nrthreads-1); 648 } else { 649 spin_lock_bh(&pool->sp_lock); 650 nrservs -= pool->sp_nrthreads; 651 spin_unlock_bh(&pool->sp_lock); 652 } 653 654 /* create new threads */ 655 while (nrservs > 0) { 656 nrservs--; 657 chosen_pool = choose_pool(serv, pool, &state); 658 659 rqstp = svc_prepare_thread(serv, chosen_pool); 660 if (IS_ERR(rqstp)) { 661 error = PTR_ERR(rqstp); 662 break; 663 } 664 665 __module_get(serv->sv_module); 666 task = kthread_create(serv->sv_function, rqstp, serv->sv_name); 667 if (IS_ERR(task)) { 668 error = PTR_ERR(task); 669 module_put(serv->sv_module); 670 svc_exit_thread(rqstp); 671 break; 672 } 673 674 rqstp->rq_task = task; 675 if (serv->sv_nrpools > 1) 676 svc_pool_map_set_cpumask(task, chosen_pool->sp_id); 677 678 svc_sock_update_bufs(serv); 679 wake_up_process(task); 680 } 681 /* destroy old threads */ 682 while (nrservs < 0 && 683 (task = choose_victim(serv, pool, &state)) != NULL) { 684 send_sig(SIGINT, task, 1); 685 nrservs++; 686 } 687 688 return error; 689 } 690 EXPORT_SYMBOL_GPL(svc_set_num_threads); 691 692 /* 693 * Called from a server thread as it's exiting. Caller must hold the BKL or 694 * the "service mutex", whichever is appropriate for the service. 695 */ 696 void 697 svc_exit_thread(struct svc_rqst *rqstp) 698 { 699 struct svc_serv *serv = rqstp->rq_server; 700 struct svc_pool *pool = rqstp->rq_pool; 701 702 svc_release_buffer(rqstp); 703 kfree(rqstp->rq_resp); 704 kfree(rqstp->rq_argp); 705 kfree(rqstp->rq_auth_data); 706 707 spin_lock_bh(&pool->sp_lock); 708 pool->sp_nrthreads--; 709 list_del(&rqstp->rq_all); 710 spin_unlock_bh(&pool->sp_lock); 711 712 kfree(rqstp); 713 714 /* Release the server */ 715 if (serv) 716 svc_destroy(serv); 717 } 718 EXPORT_SYMBOL_GPL(svc_exit_thread); 719 720 /* 721 * Register an "inet" protocol family netid with the local 722 * rpcbind daemon via an rpcbind v4 SET request. 723 * 724 * No netconfig infrastructure is available in the kernel, so 725 * we map IP_ protocol numbers to netids by hand. 726 * 727 * Returns zero on success; a negative errno value is returned 728 * if any error occurs. 729 */ 730 static int __svc_rpcb_register4(const u32 program, const u32 version, 731 const unsigned short protocol, 732 const unsigned short port) 733 { 734 const struct sockaddr_in sin = { 735 .sin_family = AF_INET, 736 .sin_addr.s_addr = htonl(INADDR_ANY), 737 .sin_port = htons(port), 738 }; 739 const char *netid; 740 int error; 741 742 switch (protocol) { 743 case IPPROTO_UDP: 744 netid = RPCBIND_NETID_UDP; 745 break; 746 case IPPROTO_TCP: 747 netid = RPCBIND_NETID_TCP; 748 break; 749 default: 750 return -ENOPROTOOPT; 751 } 752 753 error = rpcb_v4_register(program, version, 754 (const struct sockaddr *)&sin, netid); 755 756 /* 757 * User space didn't support rpcbind v4, so retry this 758 * registration request with the legacy rpcbind v2 protocol. 759 */ 760 if (error == -EPROTONOSUPPORT) 761 error = rpcb_register(program, version, protocol, port); 762 763 return error; 764 } 765 766 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 767 /* 768 * Register an "inet6" protocol family netid with the local 769 * rpcbind daemon via an rpcbind v4 SET request. 770 * 771 * No netconfig infrastructure is available in the kernel, so 772 * we map IP_ protocol numbers to netids by hand. 773 * 774 * Returns zero on success; a negative errno value is returned 775 * if any error occurs. 776 */ 777 static int __svc_rpcb_register6(const u32 program, const u32 version, 778 const unsigned short protocol, 779 const unsigned short port) 780 { 781 const struct sockaddr_in6 sin6 = { 782 .sin6_family = AF_INET6, 783 .sin6_addr = IN6ADDR_ANY_INIT, 784 .sin6_port = htons(port), 785 }; 786 const char *netid; 787 int error; 788 789 switch (protocol) { 790 case IPPROTO_UDP: 791 netid = RPCBIND_NETID_UDP6; 792 break; 793 case IPPROTO_TCP: 794 netid = RPCBIND_NETID_TCP6; 795 break; 796 default: 797 return -ENOPROTOOPT; 798 } 799 800 error = rpcb_v4_register(program, version, 801 (const struct sockaddr *)&sin6, netid); 802 803 /* 804 * User space didn't support rpcbind version 4, so we won't 805 * use a PF_INET6 listener. 806 */ 807 if (error == -EPROTONOSUPPORT) 808 error = -EAFNOSUPPORT; 809 810 return error; 811 } 812 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */ 813 814 /* 815 * Register a kernel RPC service via rpcbind version 4. 816 * 817 * Returns zero on success; a negative errno value is returned 818 * if any error occurs. 819 */ 820 static int __svc_register(const char *progname, 821 const u32 program, const u32 version, 822 const int family, 823 const unsigned short protocol, 824 const unsigned short port) 825 { 826 int error = -EAFNOSUPPORT; 827 828 switch (family) { 829 case PF_INET: 830 error = __svc_rpcb_register4(program, version, 831 protocol, port); 832 break; 833 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) 834 case PF_INET6: 835 error = __svc_rpcb_register6(program, version, 836 protocol, port); 837 #endif /* defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) */ 838 } 839 840 if (error < 0) 841 printk(KERN_WARNING "svc: failed to register %sv%u RPC " 842 "service (errno %d).\n", progname, version, -error); 843 return error; 844 } 845 846 /** 847 * svc_register - register an RPC service with the local portmapper 848 * @serv: svc_serv struct for the service to register 849 * @family: protocol family of service's listener socket 850 * @proto: transport protocol number to advertise 851 * @port: port to advertise 852 * 853 * Service is registered for any address in the passed-in protocol family 854 */ 855 int svc_register(const struct svc_serv *serv, const int family, 856 const unsigned short proto, const unsigned short port) 857 { 858 struct svc_program *progp; 859 unsigned int i; 860 int error = 0; 861 862 BUG_ON(proto == 0 && port == 0); 863 864 for (progp = serv->sv_program; progp; progp = progp->pg_next) { 865 for (i = 0; i < progp->pg_nvers; i++) { 866 if (progp->pg_vers[i] == NULL) 867 continue; 868 869 dprintk("svc: svc_register(%sv%d, %s, %u, %u)%s\n", 870 progp->pg_name, 871 i, 872 proto == IPPROTO_UDP? "udp" : "tcp", 873 port, 874 family, 875 progp->pg_vers[i]->vs_hidden? 876 " (but not telling portmap)" : ""); 877 878 if (progp->pg_vers[i]->vs_hidden) 879 continue; 880 881 error = __svc_register(progp->pg_name, progp->pg_prog, 882 i, family, proto, port); 883 if (error < 0) 884 break; 885 } 886 } 887 888 return error; 889 } 890 891 /* 892 * If user space is running rpcbind, it should take the v4 UNSET 893 * and clear everything for this [program, version]. If user space 894 * is running portmap, it will reject the v4 UNSET, but won't have 895 * any "inet6" entries anyway. So a PMAP_UNSET should be sufficient 896 * in this case to clear all existing entries for [program, version]. 897 */ 898 static void __svc_unregister(const u32 program, const u32 version, 899 const char *progname) 900 { 901 int error; 902 903 error = rpcb_v4_register(program, version, NULL, ""); 904 905 /* 906 * User space didn't support rpcbind v4, so retry this 907 * request with the legacy rpcbind v2 protocol. 908 */ 909 if (error == -EPROTONOSUPPORT) 910 error = rpcb_register(program, version, 0, 0); 911 912 dprintk("svc: %s(%sv%u), error %d\n", 913 __func__, progname, version, error); 914 } 915 916 /* 917 * All netids, bind addresses and ports registered for [program, version] 918 * are removed from the local rpcbind database (if the service is not 919 * hidden) to make way for a new instance of the service. 920 * 921 * The result of unregistration is reported via dprintk for those who want 922 * verification of the result, but is otherwise not important. 923 */ 924 static void svc_unregister(const struct svc_serv *serv) 925 { 926 struct svc_program *progp; 927 unsigned long flags; 928 unsigned int i; 929 930 clear_thread_flag(TIF_SIGPENDING); 931 932 for (progp = serv->sv_program; progp; progp = progp->pg_next) { 933 for (i = 0; i < progp->pg_nvers; i++) { 934 if (progp->pg_vers[i] == NULL) 935 continue; 936 if (progp->pg_vers[i]->vs_hidden) 937 continue; 938 939 __svc_unregister(progp->pg_prog, i, progp->pg_name); 940 } 941 } 942 943 spin_lock_irqsave(¤t->sighand->siglock, flags); 944 recalc_sigpending(); 945 spin_unlock_irqrestore(¤t->sighand->siglock, flags); 946 } 947 948 /* 949 * Printk the given error with the address of the client that caused it. 950 */ 951 static int 952 __attribute__ ((format (printf, 2, 3))) 953 svc_printk(struct svc_rqst *rqstp, const char *fmt, ...) 954 { 955 va_list args; 956 int r; 957 char buf[RPC_MAX_ADDRBUFLEN]; 958 959 if (!net_ratelimit()) 960 return 0; 961 962 printk(KERN_WARNING "svc: %s: ", 963 svc_print_addr(rqstp, buf, sizeof(buf))); 964 965 va_start(args, fmt); 966 r = vprintk(fmt, args); 967 va_end(args); 968 969 return r; 970 } 971 972 /* 973 * Process the RPC request. 974 */ 975 int 976 svc_process(struct svc_rqst *rqstp) 977 { 978 struct svc_program *progp; 979 struct svc_version *versp = NULL; /* compiler food */ 980 struct svc_procedure *procp = NULL; 981 struct kvec * argv = &rqstp->rq_arg.head[0]; 982 struct kvec * resv = &rqstp->rq_res.head[0]; 983 struct svc_serv *serv = rqstp->rq_server; 984 kxdrproc_t xdr; 985 __be32 *statp; 986 u32 dir, prog, vers, proc; 987 __be32 auth_stat, rpc_stat; 988 int auth_res; 989 __be32 *reply_statp; 990 991 rpc_stat = rpc_success; 992 993 if (argv->iov_len < 6*4) 994 goto err_short_len; 995 996 /* setup response xdr_buf. 997 * Initially it has just one page 998 */ 999 rqstp->rq_resused = 1; 1000 resv->iov_base = page_address(rqstp->rq_respages[0]); 1001 resv->iov_len = 0; 1002 rqstp->rq_res.pages = rqstp->rq_respages + 1; 1003 rqstp->rq_res.len = 0; 1004 rqstp->rq_res.page_base = 0; 1005 rqstp->rq_res.page_len = 0; 1006 rqstp->rq_res.buflen = PAGE_SIZE; 1007 rqstp->rq_res.tail[0].iov_base = NULL; 1008 rqstp->rq_res.tail[0].iov_len = 0; 1009 /* Will be turned off only in gss privacy case: */ 1010 rqstp->rq_splice_ok = 1; 1011 /* Will be turned off only when NFSv4 Sessions are used */ 1012 rqstp->rq_usedeferral = 1; 1013 1014 /* Setup reply header */ 1015 rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); 1016 1017 rqstp->rq_xid = svc_getu32(argv); 1018 svc_putu32(resv, rqstp->rq_xid); 1019 1020 dir = svc_getnl(argv); 1021 vers = svc_getnl(argv); 1022 1023 /* First words of reply: */ 1024 svc_putnl(resv, 1); /* REPLY */ 1025 1026 if (dir != 0) /* direction != CALL */ 1027 goto err_bad_dir; 1028 if (vers != 2) /* RPC version number */ 1029 goto err_bad_rpc; 1030 1031 /* Save position in case we later decide to reject: */ 1032 reply_statp = resv->iov_base + resv->iov_len; 1033 1034 svc_putnl(resv, 0); /* ACCEPT */ 1035 1036 rqstp->rq_prog = prog = svc_getnl(argv); /* program number */ 1037 rqstp->rq_vers = vers = svc_getnl(argv); /* version number */ 1038 rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */ 1039 1040 progp = serv->sv_program; 1041 1042 for (progp = serv->sv_program; progp; progp = progp->pg_next) 1043 if (prog == progp->pg_prog) 1044 break; 1045 1046 /* 1047 * Decode auth data, and add verifier to reply buffer. 1048 * We do this before anything else in order to get a decent 1049 * auth verifier. 1050 */ 1051 auth_res = svc_authenticate(rqstp, &auth_stat); 1052 /* Also give the program a chance to reject this call: */ 1053 if (auth_res == SVC_OK && progp) { 1054 auth_stat = rpc_autherr_badcred; 1055 auth_res = progp->pg_authenticate(rqstp); 1056 } 1057 switch (auth_res) { 1058 case SVC_OK: 1059 break; 1060 case SVC_GARBAGE: 1061 goto err_garbage; 1062 case SVC_SYSERR: 1063 rpc_stat = rpc_system_err; 1064 goto err_bad; 1065 case SVC_DENIED: 1066 goto err_bad_auth; 1067 case SVC_DROP: 1068 goto dropit; 1069 case SVC_COMPLETE: 1070 goto sendit; 1071 } 1072 1073 if (progp == NULL) 1074 goto err_bad_prog; 1075 1076 if (vers >= progp->pg_nvers || 1077 !(versp = progp->pg_vers[vers])) 1078 goto err_bad_vers; 1079 1080 procp = versp->vs_proc + proc; 1081 if (proc >= versp->vs_nproc || !procp->pc_func) 1082 goto err_bad_proc; 1083 rqstp->rq_procinfo = procp; 1084 1085 /* Syntactic check complete */ 1086 serv->sv_stats->rpccnt++; 1087 1088 /* Build the reply header. */ 1089 statp = resv->iov_base +resv->iov_len; 1090 svc_putnl(resv, RPC_SUCCESS); 1091 1092 /* Bump per-procedure stats counter */ 1093 procp->pc_count++; 1094 1095 /* Initialize storage for argp and resp */ 1096 memset(rqstp->rq_argp, 0, procp->pc_argsize); 1097 memset(rqstp->rq_resp, 0, procp->pc_ressize); 1098 1099 /* un-reserve some of the out-queue now that we have a 1100 * better idea of reply size 1101 */ 1102 if (procp->pc_xdrressize) 1103 svc_reserve_auth(rqstp, procp->pc_xdrressize<<2); 1104 1105 /* Call the function that processes the request. */ 1106 if (!versp->vs_dispatch) { 1107 /* Decode arguments */ 1108 xdr = procp->pc_decode; 1109 if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp)) 1110 goto err_garbage; 1111 1112 *statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); 1113 1114 /* Encode reply */ 1115 if (*statp == rpc_drop_reply) { 1116 if (procp->pc_release) 1117 procp->pc_release(rqstp, NULL, rqstp->rq_resp); 1118 goto dropit; 1119 } 1120 if (*statp == rpc_success && (xdr = procp->pc_encode) 1121 && !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) { 1122 dprintk("svc: failed to encode reply\n"); 1123 /* serv->sv_stats->rpcsystemerr++; */ 1124 *statp = rpc_system_err; 1125 } 1126 } else { 1127 dprintk("svc: calling dispatcher\n"); 1128 if (!versp->vs_dispatch(rqstp, statp)) { 1129 /* Release reply info */ 1130 if (procp->pc_release) 1131 procp->pc_release(rqstp, NULL, rqstp->rq_resp); 1132 goto dropit; 1133 } 1134 } 1135 1136 /* Check RPC status result */ 1137 if (*statp != rpc_success) 1138 resv->iov_len = ((void*)statp) - resv->iov_base + 4; 1139 1140 /* Release reply info */ 1141 if (procp->pc_release) 1142 procp->pc_release(rqstp, NULL, rqstp->rq_resp); 1143 1144 if (procp->pc_encode == NULL) 1145 goto dropit; 1146 1147 sendit: 1148 if (svc_authorise(rqstp)) 1149 goto dropit; 1150 return svc_send(rqstp); 1151 1152 dropit: 1153 svc_authorise(rqstp); /* doesn't hurt to call this twice */ 1154 dprintk("svc: svc_process dropit\n"); 1155 svc_drop(rqstp); 1156 return 0; 1157 1158 err_short_len: 1159 svc_printk(rqstp, "short len %Zd, dropping request\n", 1160 argv->iov_len); 1161 1162 goto dropit; /* drop request */ 1163 1164 err_bad_dir: 1165 svc_printk(rqstp, "bad direction %d, dropping request\n", dir); 1166 1167 serv->sv_stats->rpcbadfmt++; 1168 goto dropit; /* drop request */ 1169 1170 err_bad_rpc: 1171 serv->sv_stats->rpcbadfmt++; 1172 svc_putnl(resv, 1); /* REJECT */ 1173 svc_putnl(resv, 0); /* RPC_MISMATCH */ 1174 svc_putnl(resv, 2); /* Only RPCv2 supported */ 1175 svc_putnl(resv, 2); 1176 goto sendit; 1177 1178 err_bad_auth: 1179 dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat)); 1180 serv->sv_stats->rpcbadauth++; 1181 /* Restore write pointer to location of accept status: */ 1182 xdr_ressize_check(rqstp, reply_statp); 1183 svc_putnl(resv, 1); /* REJECT */ 1184 svc_putnl(resv, 1); /* AUTH_ERROR */ 1185 svc_putnl(resv, ntohl(auth_stat)); /* status */ 1186 goto sendit; 1187 1188 err_bad_prog: 1189 dprintk("svc: unknown program %d\n", prog); 1190 serv->sv_stats->rpcbadfmt++; 1191 svc_putnl(resv, RPC_PROG_UNAVAIL); 1192 goto sendit; 1193 1194 err_bad_vers: 1195 svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n", 1196 vers, prog, progp->pg_name); 1197 1198 serv->sv_stats->rpcbadfmt++; 1199 svc_putnl(resv, RPC_PROG_MISMATCH); 1200 svc_putnl(resv, progp->pg_lovers); 1201 svc_putnl(resv, progp->pg_hivers); 1202 goto sendit; 1203 1204 err_bad_proc: 1205 svc_printk(rqstp, "unknown procedure (%d)\n", proc); 1206 1207 serv->sv_stats->rpcbadfmt++; 1208 svc_putnl(resv, RPC_PROC_UNAVAIL); 1209 goto sendit; 1210 1211 err_garbage: 1212 svc_printk(rqstp, "failed to decode args\n"); 1213 1214 rpc_stat = rpc_garbage_args; 1215 err_bad: 1216 serv->sv_stats->rpcbadfmt++; 1217 svc_putnl(resv, ntohl(rpc_stat)); 1218 goto sendit; 1219 } 1220 EXPORT_SYMBOL_GPL(svc_process); 1221 1222 /* 1223 * Return (transport-specific) limit on the rpc payload. 1224 */ 1225 u32 svc_max_payload(const struct svc_rqst *rqstp) 1226 { 1227 u32 max = rqstp->rq_xprt->xpt_class->xcl_max_payload; 1228 1229 if (rqstp->rq_server->sv_max_payload < max) 1230 max = rqstp->rq_server->sv_max_payload; 1231 return max; 1232 } 1233 EXPORT_SYMBOL_GPL(svc_max_payload); 1234