1 /* 2 * linux/net/sunrpc/clnt.c 3 * 4 * This file contains the high-level RPC interface. 5 * It is modeled as a finite state machine to support both synchronous 6 * and asynchronous requests. 7 * 8 * - RPC header generation and argument serialization. 9 * - Credential refresh. 10 * - TCP connect handling. 11 * - Retry of operation when it is suspected the operation failed because 12 * of uid squashing on the server, or when the credentials were stale 13 * and need to be refreshed, or when a packet was damaged in transit. 14 * This may be have to be moved to the VFS layer. 15 * 16 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 18 */ 19 20 #include <asm/system.h> 21 22 #include <linux/module.h> 23 #include <linux/types.h> 24 #include <linux/kallsyms.h> 25 #include <linux/mm.h> 26 #include <linux/namei.h> 27 #include <linux/mount.h> 28 #include <linux/slab.h> 29 #include <linux/utsname.h> 30 #include <linux/workqueue.h> 31 #include <linux/in.h> 32 #include <linux/in6.h> 33 #include <linux/un.h> 34 35 #include <linux/sunrpc/clnt.h> 36 #include <linux/sunrpc/rpc_pipe_fs.h> 37 #include <linux/sunrpc/metrics.h> 38 #include <linux/sunrpc/bc_xprt.h> 39 40 #include "sunrpc.h" 41 #include "netns.h" 42 43 #ifdef RPC_DEBUG 44 # define RPCDBG_FACILITY RPCDBG_CALL 45 #endif 46 47 #define dprint_status(t) \ 48 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 49 __func__, t->tk_status) 50 51 /* 52 * All RPC clients are linked into this list 53 */ 54 55 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 56 57 58 static void call_start(struct rpc_task *task); 59 static void call_reserve(struct rpc_task *task); 60 static void call_reserveresult(struct rpc_task *task); 61 static void call_allocate(struct rpc_task *task); 62 static void call_decode(struct rpc_task *task); 63 static void call_bind(struct rpc_task *task); 64 static void call_bind_status(struct rpc_task *task); 65 static void call_transmit(struct rpc_task *task); 66 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 67 static void call_bc_transmit(struct rpc_task *task); 68 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 69 static void call_status(struct rpc_task *task); 70 static void call_transmit_status(struct rpc_task *task); 71 static void call_refresh(struct rpc_task *task); 72 static void call_refreshresult(struct rpc_task *task); 73 static void call_timeout(struct rpc_task *task); 74 static void call_connect(struct rpc_task *task); 75 static void call_connect_status(struct rpc_task *task); 76 77 static __be32 *rpc_encode_header(struct rpc_task *task); 78 static __be32 *rpc_verify_header(struct rpc_task *task); 79 static int rpc_ping(struct rpc_clnt *clnt); 80 81 static void rpc_register_client(struct rpc_clnt *clnt) 82 { 83 struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id); 84 85 spin_lock(&sn->rpc_client_lock); 86 list_add(&clnt->cl_clients, &sn->all_clients); 87 spin_unlock(&sn->rpc_client_lock); 88 } 89 90 static void rpc_unregister_client(struct rpc_clnt *clnt) 91 { 92 struct sunrpc_net *sn = net_generic(clnt->cl_xprt->xprt_net, sunrpc_net_id); 93 94 spin_lock(&sn->rpc_client_lock); 95 list_del(&clnt->cl_clients); 96 spin_unlock(&sn->rpc_client_lock); 97 } 98 99 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 100 { 101 if (clnt->cl_dentry) { 102 if (clnt->cl_auth && clnt->cl_auth->au_ops->pipes_destroy) 103 clnt->cl_auth->au_ops->pipes_destroy(clnt->cl_auth); 104 rpc_remove_client_dir(clnt->cl_dentry); 105 } 106 clnt->cl_dentry = NULL; 107 } 108 109 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 110 { 111 struct super_block *pipefs_sb; 112 113 pipefs_sb = rpc_get_sb_net(clnt->cl_xprt->xprt_net); 114 if (pipefs_sb) { 115 __rpc_clnt_remove_pipedir(clnt); 116 rpc_put_sb_net(clnt->cl_xprt->xprt_net); 117 } 118 } 119 120 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 121 struct rpc_clnt *clnt, 122 const char *dir_name) 123 { 124 static uint32_t clntid; 125 char name[15]; 126 struct qstr q = { 127 .name = name, 128 }; 129 struct dentry *dir, *dentry; 130 int error; 131 132 dir = rpc_d_lookup_sb(sb, dir_name); 133 if (dir == NULL) 134 return dir; 135 for (;;) { 136 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 137 name[sizeof(name) - 1] = '\0'; 138 q.hash = full_name_hash(q.name, q.len); 139 dentry = rpc_create_client_dir(dir, &q, clnt); 140 if (!IS_ERR(dentry)) 141 break; 142 error = PTR_ERR(dentry); 143 if (error != -EEXIST) { 144 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 145 " %s/%s, error %d\n", 146 dir_name, name, error); 147 break; 148 } 149 } 150 dput(dir); 151 return dentry; 152 } 153 154 static int 155 rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name) 156 { 157 struct super_block *pipefs_sb; 158 struct dentry *dentry; 159 160 clnt->cl_dentry = NULL; 161 if (dir_name == NULL) 162 return 0; 163 pipefs_sb = rpc_get_sb_net(clnt->cl_xprt->xprt_net); 164 if (!pipefs_sb) 165 return 0; 166 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt, dir_name); 167 rpc_put_sb_net(clnt->cl_xprt->xprt_net); 168 if (IS_ERR(dentry)) 169 return PTR_ERR(dentry); 170 clnt->cl_dentry = dentry; 171 return 0; 172 } 173 174 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 175 struct super_block *sb) 176 { 177 struct dentry *dentry; 178 int err = 0; 179 180 switch (event) { 181 case RPC_PIPEFS_MOUNT: 182 if (clnt->cl_program->pipe_dir_name == NULL) 183 break; 184 dentry = rpc_setup_pipedir_sb(sb, clnt, 185 clnt->cl_program->pipe_dir_name); 186 BUG_ON(dentry == NULL); 187 if (IS_ERR(dentry)) 188 return PTR_ERR(dentry); 189 clnt->cl_dentry = dentry; 190 if (clnt->cl_auth->au_ops->pipes_create) { 191 err = clnt->cl_auth->au_ops->pipes_create(clnt->cl_auth); 192 if (err) 193 __rpc_clnt_remove_pipedir(clnt); 194 } 195 break; 196 case RPC_PIPEFS_UMOUNT: 197 __rpc_clnt_remove_pipedir(clnt); 198 break; 199 default: 200 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 201 return -ENOTSUPP; 202 } 203 return err; 204 } 205 206 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 207 void *ptr) 208 { 209 struct super_block *sb = ptr; 210 struct rpc_clnt *clnt; 211 int error = 0; 212 struct sunrpc_net *sn = net_generic(sb->s_fs_info, sunrpc_net_id); 213 214 spin_lock(&sn->rpc_client_lock); 215 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 216 error = __rpc_pipefs_event(clnt, event, sb); 217 if (error) 218 break; 219 } 220 spin_unlock(&sn->rpc_client_lock); 221 return error; 222 } 223 224 static struct notifier_block rpc_clients_block = { 225 .notifier_call = rpc_pipefs_event, 226 .priority = SUNRPC_PIPEFS_RPC_PRIO, 227 }; 228 229 int rpc_clients_notifier_register(void) 230 { 231 return rpc_pipefs_notifier_register(&rpc_clients_block); 232 } 233 234 void rpc_clients_notifier_unregister(void) 235 { 236 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 237 } 238 239 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt) 240 { 241 struct rpc_program *program = args->program; 242 struct rpc_version *version; 243 struct rpc_clnt *clnt = NULL; 244 struct rpc_auth *auth; 245 int err; 246 size_t len; 247 248 /* sanity check the name before trying to print it */ 249 err = -EINVAL; 250 len = strlen(args->servername); 251 if (len > RPC_MAXNETNAMELEN) 252 goto out_no_rpciod; 253 len++; 254 255 dprintk("RPC: creating %s client for %s (xprt %p)\n", 256 program->name, args->servername, xprt); 257 258 err = rpciod_up(); 259 if (err) 260 goto out_no_rpciod; 261 err = -EINVAL; 262 if (!xprt) 263 goto out_no_xprt; 264 265 if (args->version >= program->nrvers) 266 goto out_err; 267 version = program->version[args->version]; 268 if (version == NULL) 269 goto out_err; 270 271 err = -ENOMEM; 272 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 273 if (!clnt) 274 goto out_err; 275 clnt->cl_parent = clnt; 276 277 clnt->cl_server = kstrdup(args->servername, GFP_KERNEL); 278 if (clnt->cl_server == NULL) 279 goto out_no_server; 280 281 clnt->cl_xprt = xprt; 282 clnt->cl_procinfo = version->procs; 283 clnt->cl_maxproc = version->nrprocs; 284 clnt->cl_protname = program->name; 285 clnt->cl_prog = args->prognumber ? : program->number; 286 clnt->cl_vers = version->number; 287 clnt->cl_stats = program->stats; 288 clnt->cl_metrics = rpc_alloc_iostats(clnt); 289 err = -ENOMEM; 290 if (clnt->cl_metrics == NULL) 291 goto out_no_stats; 292 clnt->cl_program = program; 293 INIT_LIST_HEAD(&clnt->cl_tasks); 294 spin_lock_init(&clnt->cl_lock); 295 296 if (!xprt_bound(clnt->cl_xprt)) 297 clnt->cl_autobind = 1; 298 299 clnt->cl_timeout = xprt->timeout; 300 if (args->timeout != NULL) { 301 memcpy(&clnt->cl_timeout_default, args->timeout, 302 sizeof(clnt->cl_timeout_default)); 303 clnt->cl_timeout = &clnt->cl_timeout_default; 304 } 305 306 clnt->cl_rtt = &clnt->cl_rtt_default; 307 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 308 clnt->cl_principal = NULL; 309 if (args->client_name) { 310 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL); 311 if (!clnt->cl_principal) 312 goto out_no_principal; 313 } 314 315 atomic_set(&clnt->cl_count, 1); 316 317 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 318 if (err < 0) 319 goto out_no_path; 320 321 auth = rpcauth_create(args->authflavor, clnt); 322 if (IS_ERR(auth)) { 323 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 324 args->authflavor); 325 err = PTR_ERR(auth); 326 goto out_no_auth; 327 } 328 329 /* save the nodename */ 330 clnt->cl_nodelen = strlen(init_utsname()->nodename); 331 if (clnt->cl_nodelen > UNX_MAXNODENAME) 332 clnt->cl_nodelen = UNX_MAXNODENAME; 333 memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen); 334 rpc_register_client(clnt); 335 return clnt; 336 337 out_no_auth: 338 rpc_clnt_remove_pipedir(clnt); 339 out_no_path: 340 kfree(clnt->cl_principal); 341 out_no_principal: 342 rpc_free_iostats(clnt->cl_metrics); 343 out_no_stats: 344 kfree(clnt->cl_server); 345 out_no_server: 346 kfree(clnt); 347 out_err: 348 xprt_put(xprt); 349 out_no_xprt: 350 rpciod_down(); 351 out_no_rpciod: 352 return ERR_PTR(err); 353 } 354 355 /* 356 * rpc_create - create an RPC client and transport with one call 357 * @args: rpc_clnt create argument structure 358 * 359 * Creates and initializes an RPC transport and an RPC client. 360 * 361 * It can ping the server in order to determine if it is up, and to see if 362 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 363 * this behavior so asynchronous tasks can also use rpc_create. 364 */ 365 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 366 { 367 struct rpc_xprt *xprt; 368 struct rpc_clnt *clnt; 369 struct xprt_create xprtargs = { 370 .net = args->net, 371 .ident = args->protocol, 372 .srcaddr = args->saddress, 373 .dstaddr = args->address, 374 .addrlen = args->addrsize, 375 .bc_xprt = args->bc_xprt, 376 }; 377 char servername[48]; 378 379 /* 380 * If the caller chooses not to specify a hostname, whip 381 * up a string representation of the passed-in address. 382 */ 383 if (args->servername == NULL) { 384 struct sockaddr_un *sun = 385 (struct sockaddr_un *)args->address; 386 struct sockaddr_in *sin = 387 (struct sockaddr_in *)args->address; 388 struct sockaddr_in6 *sin6 = 389 (struct sockaddr_in6 *)args->address; 390 391 servername[0] = '\0'; 392 switch (args->address->sa_family) { 393 case AF_LOCAL: 394 snprintf(servername, sizeof(servername), "%s", 395 sun->sun_path); 396 break; 397 case AF_INET: 398 snprintf(servername, sizeof(servername), "%pI4", 399 &sin->sin_addr.s_addr); 400 break; 401 case AF_INET6: 402 snprintf(servername, sizeof(servername), "%pI6", 403 &sin6->sin6_addr); 404 break; 405 default: 406 /* caller wants default server name, but 407 * address family isn't recognized. */ 408 return ERR_PTR(-EINVAL); 409 } 410 args->servername = servername; 411 } 412 413 xprt = xprt_create_transport(&xprtargs); 414 if (IS_ERR(xprt)) 415 return (struct rpc_clnt *)xprt; 416 417 /* 418 * By default, kernel RPC client connects from a reserved port. 419 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 420 * but it is always enabled for rpciod, which handles the connect 421 * operation. 422 */ 423 xprt->resvport = 1; 424 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 425 xprt->resvport = 0; 426 427 clnt = rpc_new_client(args, xprt); 428 if (IS_ERR(clnt)) 429 return clnt; 430 431 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 432 int err = rpc_ping(clnt); 433 if (err != 0) { 434 rpc_shutdown_client(clnt); 435 return ERR_PTR(err); 436 } 437 } 438 439 clnt->cl_softrtry = 1; 440 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 441 clnt->cl_softrtry = 0; 442 443 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 444 clnt->cl_autobind = 1; 445 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 446 clnt->cl_discrtry = 1; 447 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 448 clnt->cl_chatty = 1; 449 450 return clnt; 451 } 452 EXPORT_SYMBOL_GPL(rpc_create); 453 454 /* 455 * This function clones the RPC client structure. It allows us to share the 456 * same transport while varying parameters such as the authentication 457 * flavour. 458 */ 459 struct rpc_clnt * 460 rpc_clone_client(struct rpc_clnt *clnt) 461 { 462 struct rpc_clnt *new; 463 int err = -ENOMEM; 464 465 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL); 466 if (!new) 467 goto out_no_clnt; 468 new->cl_server = kstrdup(clnt->cl_server, GFP_KERNEL); 469 if (new->cl_server == NULL) 470 goto out_no_server; 471 new->cl_parent = clnt; 472 /* Turn off autobind on clones */ 473 new->cl_autobind = 0; 474 INIT_LIST_HEAD(&new->cl_tasks); 475 spin_lock_init(&new->cl_lock); 476 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval); 477 new->cl_metrics = rpc_alloc_iostats(clnt); 478 if (new->cl_metrics == NULL) 479 goto out_no_stats; 480 if (clnt->cl_principal) { 481 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL); 482 if (new->cl_principal == NULL) 483 goto out_no_principal; 484 } 485 atomic_set(&new->cl_count, 1); 486 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); 487 if (err != 0) 488 goto out_no_path; 489 if (new->cl_auth) 490 atomic_inc(&new->cl_auth->au_count); 491 xprt_get(clnt->cl_xprt); 492 atomic_inc(&clnt->cl_count); 493 rpc_register_client(new); 494 rpciod_up(); 495 return new; 496 out_no_path: 497 kfree(new->cl_principal); 498 out_no_principal: 499 rpc_free_iostats(new->cl_metrics); 500 out_no_stats: 501 kfree(new->cl_server); 502 out_no_server: 503 kfree(new); 504 out_no_clnt: 505 dprintk("RPC: %s: returned error %d\n", __func__, err); 506 return ERR_PTR(err); 507 } 508 EXPORT_SYMBOL_GPL(rpc_clone_client); 509 510 /* 511 * Kill all tasks for the given client. 512 * XXX: kill their descendants as well? 513 */ 514 void rpc_killall_tasks(struct rpc_clnt *clnt) 515 { 516 struct rpc_task *rovr; 517 518 519 if (list_empty(&clnt->cl_tasks)) 520 return; 521 dprintk("RPC: killing all tasks for client %p\n", clnt); 522 /* 523 * Spin lock all_tasks to prevent changes... 524 */ 525 spin_lock(&clnt->cl_lock); 526 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 527 if (!RPC_IS_ACTIVATED(rovr)) 528 continue; 529 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 530 rovr->tk_flags |= RPC_TASK_KILLED; 531 rpc_exit(rovr, -EIO); 532 if (RPC_IS_QUEUED(rovr)) 533 rpc_wake_up_queued_task(rovr->tk_waitqueue, 534 rovr); 535 } 536 } 537 spin_unlock(&clnt->cl_lock); 538 } 539 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 540 541 /* 542 * Properly shut down an RPC client, terminating all outstanding 543 * requests. 544 */ 545 void rpc_shutdown_client(struct rpc_clnt *clnt) 546 { 547 dprintk("RPC: shutting down %s client for %s\n", 548 clnt->cl_protname, clnt->cl_server); 549 550 while (!list_empty(&clnt->cl_tasks)) { 551 rpc_killall_tasks(clnt); 552 wait_event_timeout(destroy_wait, 553 list_empty(&clnt->cl_tasks), 1*HZ); 554 } 555 556 rpc_release_client(clnt); 557 } 558 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 559 560 /* 561 * Free an RPC client 562 */ 563 static void 564 rpc_free_client(struct rpc_clnt *clnt) 565 { 566 dprintk("RPC: destroying %s client for %s\n", 567 clnt->cl_protname, clnt->cl_server); 568 if (clnt->cl_parent != clnt) 569 rpc_release_client(clnt->cl_parent); 570 kfree(clnt->cl_server); 571 rpc_unregister_client(clnt); 572 rpc_clnt_remove_pipedir(clnt); 573 rpc_free_iostats(clnt->cl_metrics); 574 kfree(clnt->cl_principal); 575 clnt->cl_metrics = NULL; 576 xprt_put(clnt->cl_xprt); 577 rpciod_down(); 578 kfree(clnt); 579 } 580 581 /* 582 * Free an RPC client 583 */ 584 static void 585 rpc_free_auth(struct rpc_clnt *clnt) 586 { 587 if (clnt->cl_auth == NULL) { 588 rpc_free_client(clnt); 589 return; 590 } 591 592 /* 593 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 594 * release remaining GSS contexts. This mechanism ensures 595 * that it can do so safely. 596 */ 597 atomic_inc(&clnt->cl_count); 598 rpcauth_release(clnt->cl_auth); 599 clnt->cl_auth = NULL; 600 if (atomic_dec_and_test(&clnt->cl_count)) 601 rpc_free_client(clnt); 602 } 603 604 /* 605 * Release reference to the RPC client 606 */ 607 void 608 rpc_release_client(struct rpc_clnt *clnt) 609 { 610 dprintk("RPC: rpc_release_client(%p)\n", clnt); 611 612 if (list_empty(&clnt->cl_tasks)) 613 wake_up(&destroy_wait); 614 if (atomic_dec_and_test(&clnt->cl_count)) 615 rpc_free_auth(clnt); 616 } 617 618 /** 619 * rpc_bind_new_program - bind a new RPC program to an existing client 620 * @old: old rpc_client 621 * @program: rpc program to set 622 * @vers: rpc program version 623 * 624 * Clones the rpc client and sets up a new RPC program. This is mainly 625 * of use for enabling different RPC programs to share the same transport. 626 * The Sun NFSv2/v3 ACL protocol can do this. 627 */ 628 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 629 struct rpc_program *program, 630 u32 vers) 631 { 632 struct rpc_clnt *clnt; 633 struct rpc_version *version; 634 int err; 635 636 BUG_ON(vers >= program->nrvers || !program->version[vers]); 637 version = program->version[vers]; 638 clnt = rpc_clone_client(old); 639 if (IS_ERR(clnt)) 640 goto out; 641 clnt->cl_procinfo = version->procs; 642 clnt->cl_maxproc = version->nrprocs; 643 clnt->cl_protname = program->name; 644 clnt->cl_prog = program->number; 645 clnt->cl_vers = version->number; 646 clnt->cl_stats = program->stats; 647 err = rpc_ping(clnt); 648 if (err != 0) { 649 rpc_shutdown_client(clnt); 650 clnt = ERR_PTR(err); 651 } 652 out: 653 return clnt; 654 } 655 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 656 657 void rpc_task_release_client(struct rpc_task *task) 658 { 659 struct rpc_clnt *clnt = task->tk_client; 660 661 if (clnt != NULL) { 662 /* Remove from client task list */ 663 spin_lock(&clnt->cl_lock); 664 list_del(&task->tk_task); 665 spin_unlock(&clnt->cl_lock); 666 task->tk_client = NULL; 667 668 rpc_release_client(clnt); 669 } 670 } 671 672 static 673 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 674 { 675 if (clnt != NULL) { 676 rpc_task_release_client(task); 677 task->tk_client = clnt; 678 atomic_inc(&clnt->cl_count); 679 if (clnt->cl_softrtry) 680 task->tk_flags |= RPC_TASK_SOFT; 681 /* Add to the client's list of all tasks */ 682 spin_lock(&clnt->cl_lock); 683 list_add_tail(&task->tk_task, &clnt->cl_tasks); 684 spin_unlock(&clnt->cl_lock); 685 } 686 } 687 688 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) 689 { 690 rpc_task_release_client(task); 691 rpc_task_set_client(task, clnt); 692 } 693 EXPORT_SYMBOL_GPL(rpc_task_reset_client); 694 695 696 static void 697 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 698 { 699 if (msg != NULL) { 700 task->tk_msg.rpc_proc = msg->rpc_proc; 701 task->tk_msg.rpc_argp = msg->rpc_argp; 702 task->tk_msg.rpc_resp = msg->rpc_resp; 703 if (msg->rpc_cred != NULL) 704 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 705 } 706 } 707 708 /* 709 * Default callback for async RPC calls 710 */ 711 static void 712 rpc_default_callback(struct rpc_task *task, void *data) 713 { 714 } 715 716 static const struct rpc_call_ops rpc_default_ops = { 717 .rpc_call_done = rpc_default_callback, 718 }; 719 720 /** 721 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 722 * @task_setup_data: pointer to task initialisation data 723 */ 724 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 725 { 726 struct rpc_task *task; 727 728 task = rpc_new_task(task_setup_data); 729 if (IS_ERR(task)) 730 goto out; 731 732 rpc_task_set_client(task, task_setup_data->rpc_client); 733 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 734 735 if (task->tk_action == NULL) 736 rpc_call_start(task); 737 738 atomic_inc(&task->tk_count); 739 rpc_execute(task); 740 out: 741 return task; 742 } 743 EXPORT_SYMBOL_GPL(rpc_run_task); 744 745 /** 746 * rpc_call_sync - Perform a synchronous RPC call 747 * @clnt: pointer to RPC client 748 * @msg: RPC call parameters 749 * @flags: RPC call flags 750 */ 751 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 752 { 753 struct rpc_task *task; 754 struct rpc_task_setup task_setup_data = { 755 .rpc_client = clnt, 756 .rpc_message = msg, 757 .callback_ops = &rpc_default_ops, 758 .flags = flags, 759 }; 760 int status; 761 762 BUG_ON(flags & RPC_TASK_ASYNC); 763 764 task = rpc_run_task(&task_setup_data); 765 if (IS_ERR(task)) 766 return PTR_ERR(task); 767 status = task->tk_status; 768 rpc_put_task(task); 769 return status; 770 } 771 EXPORT_SYMBOL_GPL(rpc_call_sync); 772 773 /** 774 * rpc_call_async - Perform an asynchronous RPC call 775 * @clnt: pointer to RPC client 776 * @msg: RPC call parameters 777 * @flags: RPC call flags 778 * @tk_ops: RPC call ops 779 * @data: user call data 780 */ 781 int 782 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 783 const struct rpc_call_ops *tk_ops, void *data) 784 { 785 struct rpc_task *task; 786 struct rpc_task_setup task_setup_data = { 787 .rpc_client = clnt, 788 .rpc_message = msg, 789 .callback_ops = tk_ops, 790 .callback_data = data, 791 .flags = flags|RPC_TASK_ASYNC, 792 }; 793 794 task = rpc_run_task(&task_setup_data); 795 if (IS_ERR(task)) 796 return PTR_ERR(task); 797 rpc_put_task(task); 798 return 0; 799 } 800 EXPORT_SYMBOL_GPL(rpc_call_async); 801 802 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 803 /** 804 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 805 * rpc_execute against it 806 * @req: RPC request 807 * @tk_ops: RPC call ops 808 */ 809 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 810 const struct rpc_call_ops *tk_ops) 811 { 812 struct rpc_task *task; 813 struct xdr_buf *xbufp = &req->rq_snd_buf; 814 struct rpc_task_setup task_setup_data = { 815 .callback_ops = tk_ops, 816 }; 817 818 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 819 /* 820 * Create an rpc_task to send the data 821 */ 822 task = rpc_new_task(&task_setup_data); 823 if (IS_ERR(task)) { 824 xprt_free_bc_request(req); 825 goto out; 826 } 827 task->tk_rqstp = req; 828 829 /* 830 * Set up the xdr_buf length. 831 * This also indicates that the buffer is XDR encoded already. 832 */ 833 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 834 xbufp->tail[0].iov_len; 835 836 task->tk_action = call_bc_transmit; 837 atomic_inc(&task->tk_count); 838 BUG_ON(atomic_read(&task->tk_count) != 2); 839 rpc_execute(task); 840 841 out: 842 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 843 return task; 844 } 845 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 846 847 void 848 rpc_call_start(struct rpc_task *task) 849 { 850 task->tk_action = call_start; 851 } 852 EXPORT_SYMBOL_GPL(rpc_call_start); 853 854 /** 855 * rpc_peeraddr - extract remote peer address from clnt's xprt 856 * @clnt: RPC client structure 857 * @buf: target buffer 858 * @bufsize: length of target buffer 859 * 860 * Returns the number of bytes that are actually in the stored address. 861 */ 862 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 863 { 864 size_t bytes; 865 struct rpc_xprt *xprt = clnt->cl_xprt; 866 867 bytes = sizeof(xprt->addr); 868 if (bytes > bufsize) 869 bytes = bufsize; 870 memcpy(buf, &clnt->cl_xprt->addr, bytes); 871 return xprt->addrlen; 872 } 873 EXPORT_SYMBOL_GPL(rpc_peeraddr); 874 875 /** 876 * rpc_peeraddr2str - return remote peer address in printable format 877 * @clnt: RPC client structure 878 * @format: address format 879 * 880 */ 881 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 882 enum rpc_display_format_t format) 883 { 884 struct rpc_xprt *xprt = clnt->cl_xprt; 885 886 if (xprt->address_strings[format] != NULL) 887 return xprt->address_strings[format]; 888 else 889 return "unprintable"; 890 } 891 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 892 893 void 894 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 895 { 896 struct rpc_xprt *xprt = clnt->cl_xprt; 897 if (xprt->ops->set_buffer_size) 898 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 899 } 900 EXPORT_SYMBOL_GPL(rpc_setbufsize); 901 902 /* 903 * Return size of largest payload RPC client can support, in bytes 904 * 905 * For stream transports, this is one RPC record fragment (see RFC 906 * 1831), as we don't support multi-record requests yet. For datagram 907 * transports, this is the size of an IP packet minus the IP, UDP, and 908 * RPC header sizes. 909 */ 910 size_t rpc_max_payload(struct rpc_clnt *clnt) 911 { 912 return clnt->cl_xprt->max_payload; 913 } 914 EXPORT_SYMBOL_GPL(rpc_max_payload); 915 916 /** 917 * rpc_force_rebind - force transport to check that remote port is unchanged 918 * @clnt: client to rebind 919 * 920 */ 921 void rpc_force_rebind(struct rpc_clnt *clnt) 922 { 923 if (clnt->cl_autobind) 924 xprt_clear_bound(clnt->cl_xprt); 925 } 926 EXPORT_SYMBOL_GPL(rpc_force_rebind); 927 928 /* 929 * Restart an (async) RPC call from the call_prepare state. 930 * Usually called from within the exit handler. 931 */ 932 int 933 rpc_restart_call_prepare(struct rpc_task *task) 934 { 935 if (RPC_ASSASSINATED(task)) 936 return 0; 937 task->tk_action = call_start; 938 if (task->tk_ops->rpc_call_prepare != NULL) 939 task->tk_action = rpc_prepare_task; 940 return 1; 941 } 942 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 943 944 /* 945 * Restart an (async) RPC call. Usually called from within the 946 * exit handler. 947 */ 948 int 949 rpc_restart_call(struct rpc_task *task) 950 { 951 if (RPC_ASSASSINATED(task)) 952 return 0; 953 task->tk_action = call_start; 954 return 1; 955 } 956 EXPORT_SYMBOL_GPL(rpc_restart_call); 957 958 #ifdef RPC_DEBUG 959 static const char *rpc_proc_name(const struct rpc_task *task) 960 { 961 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 962 963 if (proc) { 964 if (proc->p_name) 965 return proc->p_name; 966 else 967 return "NULL"; 968 } else 969 return "no proc"; 970 } 971 #endif 972 973 /* 974 * 0. Initial state 975 * 976 * Other FSM states can be visited zero or more times, but 977 * this state is visited exactly once for each RPC. 978 */ 979 static void 980 call_start(struct rpc_task *task) 981 { 982 struct rpc_clnt *clnt = task->tk_client; 983 984 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 985 clnt->cl_protname, clnt->cl_vers, 986 rpc_proc_name(task), 987 (RPC_IS_ASYNC(task) ? "async" : "sync")); 988 989 /* Increment call count */ 990 task->tk_msg.rpc_proc->p_count++; 991 clnt->cl_stats->rpccnt++; 992 task->tk_action = call_reserve; 993 } 994 995 /* 996 * 1. Reserve an RPC call slot 997 */ 998 static void 999 call_reserve(struct rpc_task *task) 1000 { 1001 dprint_status(task); 1002 1003 task->tk_status = 0; 1004 task->tk_action = call_reserveresult; 1005 xprt_reserve(task); 1006 } 1007 1008 /* 1009 * 1b. Grok the result of xprt_reserve() 1010 */ 1011 static void 1012 call_reserveresult(struct rpc_task *task) 1013 { 1014 int status = task->tk_status; 1015 1016 dprint_status(task); 1017 1018 /* 1019 * After a call to xprt_reserve(), we must have either 1020 * a request slot or else an error status. 1021 */ 1022 task->tk_status = 0; 1023 if (status >= 0) { 1024 if (task->tk_rqstp) { 1025 task->tk_action = call_refresh; 1026 return; 1027 } 1028 1029 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1030 __func__, status); 1031 rpc_exit(task, -EIO); 1032 return; 1033 } 1034 1035 /* 1036 * Even though there was an error, we may have acquired 1037 * a request slot somehow. Make sure not to leak it. 1038 */ 1039 if (task->tk_rqstp) { 1040 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1041 __func__, status); 1042 xprt_release(task); 1043 } 1044 1045 switch (status) { 1046 case -EAGAIN: /* woken up; retry */ 1047 task->tk_action = call_reserve; 1048 return; 1049 case -EIO: /* probably a shutdown */ 1050 break; 1051 default: 1052 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1053 __func__, status); 1054 break; 1055 } 1056 rpc_exit(task, status); 1057 } 1058 1059 /* 1060 * 2. Bind and/or refresh the credentials 1061 */ 1062 static void 1063 call_refresh(struct rpc_task *task) 1064 { 1065 dprint_status(task); 1066 1067 task->tk_action = call_refreshresult; 1068 task->tk_status = 0; 1069 task->tk_client->cl_stats->rpcauthrefresh++; 1070 rpcauth_refreshcred(task); 1071 } 1072 1073 /* 1074 * 2a. Process the results of a credential refresh 1075 */ 1076 static void 1077 call_refreshresult(struct rpc_task *task) 1078 { 1079 int status = task->tk_status; 1080 1081 dprint_status(task); 1082 1083 task->tk_status = 0; 1084 task->tk_action = call_refresh; 1085 switch (status) { 1086 case 0: 1087 if (rpcauth_uptodatecred(task)) 1088 task->tk_action = call_allocate; 1089 return; 1090 case -ETIMEDOUT: 1091 rpc_delay(task, 3*HZ); 1092 case -EAGAIN: 1093 status = -EACCES; 1094 if (!task->tk_cred_retry) 1095 break; 1096 task->tk_cred_retry--; 1097 dprintk("RPC: %5u %s: retry refresh creds\n", 1098 task->tk_pid, __func__); 1099 return; 1100 } 1101 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1102 task->tk_pid, __func__, status); 1103 rpc_exit(task, status); 1104 } 1105 1106 /* 1107 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1108 * (Note: buffer memory is freed in xprt_release). 1109 */ 1110 static void 1111 call_allocate(struct rpc_task *task) 1112 { 1113 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1114 struct rpc_rqst *req = task->tk_rqstp; 1115 struct rpc_xprt *xprt = task->tk_xprt; 1116 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1117 1118 dprint_status(task); 1119 1120 task->tk_status = 0; 1121 task->tk_action = call_bind; 1122 1123 if (req->rq_buffer) 1124 return; 1125 1126 if (proc->p_proc != 0) { 1127 BUG_ON(proc->p_arglen == 0); 1128 if (proc->p_decode != NULL) 1129 BUG_ON(proc->p_replen == 0); 1130 } 1131 1132 /* 1133 * Calculate the size (in quads) of the RPC call 1134 * and reply headers, and convert both values 1135 * to byte sizes. 1136 */ 1137 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1138 req->rq_callsize <<= 2; 1139 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1140 req->rq_rcvsize <<= 2; 1141 1142 req->rq_buffer = xprt->ops->buf_alloc(task, 1143 req->rq_callsize + req->rq_rcvsize); 1144 if (req->rq_buffer != NULL) 1145 return; 1146 1147 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1148 1149 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1150 task->tk_action = call_allocate; 1151 rpc_delay(task, HZ>>4); 1152 return; 1153 } 1154 1155 rpc_exit(task, -ERESTARTSYS); 1156 } 1157 1158 static inline int 1159 rpc_task_need_encode(struct rpc_task *task) 1160 { 1161 return task->tk_rqstp->rq_snd_buf.len == 0; 1162 } 1163 1164 static inline void 1165 rpc_task_force_reencode(struct rpc_task *task) 1166 { 1167 task->tk_rqstp->rq_snd_buf.len = 0; 1168 task->tk_rqstp->rq_bytes_sent = 0; 1169 } 1170 1171 static inline void 1172 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1173 { 1174 buf->head[0].iov_base = start; 1175 buf->head[0].iov_len = len; 1176 buf->tail[0].iov_len = 0; 1177 buf->page_len = 0; 1178 buf->flags = 0; 1179 buf->len = 0; 1180 buf->buflen = len; 1181 } 1182 1183 /* 1184 * 3. Encode arguments of an RPC call 1185 */ 1186 static void 1187 rpc_xdr_encode(struct rpc_task *task) 1188 { 1189 struct rpc_rqst *req = task->tk_rqstp; 1190 kxdreproc_t encode; 1191 __be32 *p; 1192 1193 dprint_status(task); 1194 1195 rpc_xdr_buf_init(&req->rq_snd_buf, 1196 req->rq_buffer, 1197 req->rq_callsize); 1198 rpc_xdr_buf_init(&req->rq_rcv_buf, 1199 (char *)req->rq_buffer + req->rq_callsize, 1200 req->rq_rcvsize); 1201 1202 p = rpc_encode_header(task); 1203 if (p == NULL) { 1204 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1205 rpc_exit(task, -EIO); 1206 return; 1207 } 1208 1209 encode = task->tk_msg.rpc_proc->p_encode; 1210 if (encode == NULL) 1211 return; 1212 1213 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1214 task->tk_msg.rpc_argp); 1215 } 1216 1217 /* 1218 * 4. Get the server port number if not yet set 1219 */ 1220 static void 1221 call_bind(struct rpc_task *task) 1222 { 1223 struct rpc_xprt *xprt = task->tk_xprt; 1224 1225 dprint_status(task); 1226 1227 task->tk_action = call_connect; 1228 if (!xprt_bound(xprt)) { 1229 task->tk_action = call_bind_status; 1230 task->tk_timeout = xprt->bind_timeout; 1231 xprt->ops->rpcbind(task); 1232 } 1233 } 1234 1235 /* 1236 * 4a. Sort out bind result 1237 */ 1238 static void 1239 call_bind_status(struct rpc_task *task) 1240 { 1241 int status = -EIO; 1242 1243 if (task->tk_status >= 0) { 1244 dprint_status(task); 1245 task->tk_status = 0; 1246 task->tk_action = call_connect; 1247 return; 1248 } 1249 1250 switch (task->tk_status) { 1251 case -ENOMEM: 1252 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1253 rpc_delay(task, HZ >> 2); 1254 goto retry_timeout; 1255 case -EACCES: 1256 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1257 "unavailable\n", task->tk_pid); 1258 /* fail immediately if this is an RPC ping */ 1259 if (task->tk_msg.rpc_proc->p_proc == 0) { 1260 status = -EOPNOTSUPP; 1261 break; 1262 } 1263 if (task->tk_rebind_retry == 0) 1264 break; 1265 task->tk_rebind_retry--; 1266 rpc_delay(task, 3*HZ); 1267 goto retry_timeout; 1268 case -ETIMEDOUT: 1269 dprintk("RPC: %5u rpcbind request timed out\n", 1270 task->tk_pid); 1271 goto retry_timeout; 1272 case -EPFNOSUPPORT: 1273 /* server doesn't support any rpcbind version we know of */ 1274 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1275 task->tk_pid); 1276 break; 1277 case -EPROTONOSUPPORT: 1278 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1279 task->tk_pid); 1280 task->tk_status = 0; 1281 task->tk_action = call_bind; 1282 return; 1283 case -ECONNREFUSED: /* connection problems */ 1284 case -ECONNRESET: 1285 case -ENOTCONN: 1286 case -EHOSTDOWN: 1287 case -EHOSTUNREACH: 1288 case -ENETUNREACH: 1289 case -EPIPE: 1290 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1291 task->tk_pid, task->tk_status); 1292 if (!RPC_IS_SOFTCONN(task)) { 1293 rpc_delay(task, 5*HZ); 1294 goto retry_timeout; 1295 } 1296 status = task->tk_status; 1297 break; 1298 default: 1299 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1300 task->tk_pid, -task->tk_status); 1301 } 1302 1303 rpc_exit(task, status); 1304 return; 1305 1306 retry_timeout: 1307 task->tk_action = call_timeout; 1308 } 1309 1310 /* 1311 * 4b. Connect to the RPC server 1312 */ 1313 static void 1314 call_connect(struct rpc_task *task) 1315 { 1316 struct rpc_xprt *xprt = task->tk_xprt; 1317 1318 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1319 task->tk_pid, xprt, 1320 (xprt_connected(xprt) ? "is" : "is not")); 1321 1322 task->tk_action = call_transmit; 1323 if (!xprt_connected(xprt)) { 1324 task->tk_action = call_connect_status; 1325 if (task->tk_status < 0) 1326 return; 1327 xprt_connect(task); 1328 } 1329 } 1330 1331 /* 1332 * 4c. Sort out connect result 1333 */ 1334 static void 1335 call_connect_status(struct rpc_task *task) 1336 { 1337 struct rpc_clnt *clnt = task->tk_client; 1338 int status = task->tk_status; 1339 1340 dprint_status(task); 1341 1342 task->tk_status = 0; 1343 if (status >= 0 || status == -EAGAIN) { 1344 clnt->cl_stats->netreconn++; 1345 task->tk_action = call_transmit; 1346 return; 1347 } 1348 1349 switch (status) { 1350 /* if soft mounted, test if we've timed out */ 1351 case -ETIMEDOUT: 1352 task->tk_action = call_timeout; 1353 break; 1354 default: 1355 rpc_exit(task, -EIO); 1356 } 1357 } 1358 1359 /* 1360 * 5. Transmit the RPC request, and wait for reply 1361 */ 1362 static void 1363 call_transmit(struct rpc_task *task) 1364 { 1365 dprint_status(task); 1366 1367 task->tk_action = call_status; 1368 if (task->tk_status < 0) 1369 return; 1370 task->tk_status = xprt_prepare_transmit(task); 1371 if (task->tk_status != 0) 1372 return; 1373 task->tk_action = call_transmit_status; 1374 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1375 if (rpc_task_need_encode(task)) { 1376 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); 1377 rpc_xdr_encode(task); 1378 /* Did the encode result in an error condition? */ 1379 if (task->tk_status != 0) { 1380 /* Was the error nonfatal? */ 1381 if (task->tk_status == -EAGAIN) 1382 rpc_delay(task, HZ >> 4); 1383 else 1384 rpc_exit(task, task->tk_status); 1385 return; 1386 } 1387 } 1388 xprt_transmit(task); 1389 if (task->tk_status < 0) 1390 return; 1391 /* 1392 * On success, ensure that we call xprt_end_transmit() before sleeping 1393 * in order to allow access to the socket to other RPC requests. 1394 */ 1395 call_transmit_status(task); 1396 if (rpc_reply_expected(task)) 1397 return; 1398 task->tk_action = rpc_exit_task; 1399 rpc_wake_up_queued_task(&task->tk_xprt->pending, task); 1400 } 1401 1402 /* 1403 * 5a. Handle cleanup after a transmission 1404 */ 1405 static void 1406 call_transmit_status(struct rpc_task *task) 1407 { 1408 task->tk_action = call_status; 1409 1410 /* 1411 * Common case: success. Force the compiler to put this 1412 * test first. 1413 */ 1414 if (task->tk_status == 0) { 1415 xprt_end_transmit(task); 1416 rpc_task_force_reencode(task); 1417 return; 1418 } 1419 1420 switch (task->tk_status) { 1421 case -EAGAIN: 1422 break; 1423 default: 1424 dprint_status(task); 1425 xprt_end_transmit(task); 1426 rpc_task_force_reencode(task); 1427 break; 1428 /* 1429 * Special cases: if we've been waiting on the 1430 * socket's write_space() callback, or if the 1431 * socket just returned a connection error, 1432 * then hold onto the transport lock. 1433 */ 1434 case -ECONNREFUSED: 1435 case -EHOSTDOWN: 1436 case -EHOSTUNREACH: 1437 case -ENETUNREACH: 1438 if (RPC_IS_SOFTCONN(task)) { 1439 xprt_end_transmit(task); 1440 rpc_exit(task, task->tk_status); 1441 break; 1442 } 1443 case -ECONNRESET: 1444 case -ENOTCONN: 1445 case -EPIPE: 1446 rpc_task_force_reencode(task); 1447 } 1448 } 1449 1450 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1451 /* 1452 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 1453 * addition, disconnect on connectivity errors. 1454 */ 1455 static void 1456 call_bc_transmit(struct rpc_task *task) 1457 { 1458 struct rpc_rqst *req = task->tk_rqstp; 1459 1460 BUG_ON(task->tk_status != 0); 1461 task->tk_status = xprt_prepare_transmit(task); 1462 if (task->tk_status == -EAGAIN) { 1463 /* 1464 * Could not reserve the transport. Try again after the 1465 * transport is released. 1466 */ 1467 task->tk_status = 0; 1468 task->tk_action = call_bc_transmit; 1469 return; 1470 } 1471 1472 task->tk_action = rpc_exit_task; 1473 if (task->tk_status < 0) { 1474 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1475 "error: %d\n", task->tk_status); 1476 return; 1477 } 1478 1479 xprt_transmit(task); 1480 xprt_end_transmit(task); 1481 dprint_status(task); 1482 switch (task->tk_status) { 1483 case 0: 1484 /* Success */ 1485 break; 1486 case -EHOSTDOWN: 1487 case -EHOSTUNREACH: 1488 case -ENETUNREACH: 1489 case -ETIMEDOUT: 1490 /* 1491 * Problem reaching the server. Disconnect and let the 1492 * forechannel reestablish the connection. The server will 1493 * have to retransmit the backchannel request and we'll 1494 * reprocess it. Since these ops are idempotent, there's no 1495 * need to cache our reply at this time. 1496 */ 1497 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1498 "error: %d\n", task->tk_status); 1499 xprt_conditional_disconnect(task->tk_xprt, 1500 req->rq_connect_cookie); 1501 break; 1502 default: 1503 /* 1504 * We were unable to reply and will have to drop the 1505 * request. The server should reconnect and retransmit. 1506 */ 1507 BUG_ON(task->tk_status == -EAGAIN); 1508 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1509 "error: %d\n", task->tk_status); 1510 break; 1511 } 1512 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 1513 } 1514 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1515 1516 /* 1517 * 6. Sort out the RPC call status 1518 */ 1519 static void 1520 call_status(struct rpc_task *task) 1521 { 1522 struct rpc_clnt *clnt = task->tk_client; 1523 struct rpc_rqst *req = task->tk_rqstp; 1524 int status; 1525 1526 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 1527 task->tk_status = req->rq_reply_bytes_recvd; 1528 1529 dprint_status(task); 1530 1531 status = task->tk_status; 1532 if (status >= 0) { 1533 task->tk_action = call_decode; 1534 return; 1535 } 1536 1537 task->tk_status = 0; 1538 switch(status) { 1539 case -EHOSTDOWN: 1540 case -EHOSTUNREACH: 1541 case -ENETUNREACH: 1542 /* 1543 * Delay any retries for 3 seconds, then handle as if it 1544 * were a timeout. 1545 */ 1546 rpc_delay(task, 3*HZ); 1547 case -ETIMEDOUT: 1548 task->tk_action = call_timeout; 1549 if (task->tk_client->cl_discrtry) 1550 xprt_conditional_disconnect(task->tk_xprt, 1551 req->rq_connect_cookie); 1552 break; 1553 case -ECONNRESET: 1554 case -ECONNREFUSED: 1555 rpc_force_rebind(clnt); 1556 rpc_delay(task, 3*HZ); 1557 case -EPIPE: 1558 case -ENOTCONN: 1559 task->tk_action = call_bind; 1560 break; 1561 case -EAGAIN: 1562 task->tk_action = call_transmit; 1563 break; 1564 case -EIO: 1565 /* shutdown or soft timeout */ 1566 rpc_exit(task, status); 1567 break; 1568 default: 1569 if (clnt->cl_chatty) 1570 printk("%s: RPC call returned error %d\n", 1571 clnt->cl_protname, -status); 1572 rpc_exit(task, status); 1573 } 1574 } 1575 1576 /* 1577 * 6a. Handle RPC timeout 1578 * We do not release the request slot, so we keep using the 1579 * same XID for all retransmits. 1580 */ 1581 static void 1582 call_timeout(struct rpc_task *task) 1583 { 1584 struct rpc_clnt *clnt = task->tk_client; 1585 1586 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1587 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1588 goto retry; 1589 } 1590 1591 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1592 task->tk_timeouts++; 1593 1594 if (RPC_IS_SOFTCONN(task)) { 1595 rpc_exit(task, -ETIMEDOUT); 1596 return; 1597 } 1598 if (RPC_IS_SOFT(task)) { 1599 if (clnt->cl_chatty) 1600 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1601 clnt->cl_protname, clnt->cl_server); 1602 if (task->tk_flags & RPC_TASK_TIMEOUT) 1603 rpc_exit(task, -ETIMEDOUT); 1604 else 1605 rpc_exit(task, -EIO); 1606 return; 1607 } 1608 1609 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1610 task->tk_flags |= RPC_CALL_MAJORSEEN; 1611 if (clnt->cl_chatty) 1612 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1613 clnt->cl_protname, clnt->cl_server); 1614 } 1615 rpc_force_rebind(clnt); 1616 /* 1617 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1618 * event? RFC2203 requires the server to drop all such requests. 1619 */ 1620 rpcauth_invalcred(task); 1621 1622 retry: 1623 clnt->cl_stats->rpcretrans++; 1624 task->tk_action = call_bind; 1625 task->tk_status = 0; 1626 } 1627 1628 /* 1629 * 7. Decode the RPC reply 1630 */ 1631 static void 1632 call_decode(struct rpc_task *task) 1633 { 1634 struct rpc_clnt *clnt = task->tk_client; 1635 struct rpc_rqst *req = task->tk_rqstp; 1636 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 1637 __be32 *p; 1638 1639 dprint_status(task); 1640 1641 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1642 if (clnt->cl_chatty) 1643 printk(KERN_NOTICE "%s: server %s OK\n", 1644 clnt->cl_protname, clnt->cl_server); 1645 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1646 } 1647 1648 /* 1649 * Ensure that we see all writes made by xprt_complete_rqst() 1650 * before it changed req->rq_reply_bytes_recvd. 1651 */ 1652 smp_rmb(); 1653 req->rq_rcv_buf.len = req->rq_private_buf.len; 1654 1655 /* Check that the softirq receive buffer is valid */ 1656 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1657 sizeof(req->rq_rcv_buf)) != 0); 1658 1659 if (req->rq_rcv_buf.len < 12) { 1660 if (!RPC_IS_SOFT(task)) { 1661 task->tk_action = call_bind; 1662 clnt->cl_stats->rpcretrans++; 1663 goto out_retry; 1664 } 1665 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1666 clnt->cl_protname, task->tk_status); 1667 task->tk_action = call_timeout; 1668 goto out_retry; 1669 } 1670 1671 p = rpc_verify_header(task); 1672 if (IS_ERR(p)) { 1673 if (p == ERR_PTR(-EAGAIN)) 1674 goto out_retry; 1675 return; 1676 } 1677 1678 task->tk_action = rpc_exit_task; 1679 1680 if (decode) { 1681 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1682 task->tk_msg.rpc_resp); 1683 } 1684 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1685 task->tk_status); 1686 return; 1687 out_retry: 1688 task->tk_status = 0; 1689 /* Note: rpc_verify_header() may have freed the RPC slot */ 1690 if (task->tk_rqstp == req) { 1691 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 1692 if (task->tk_client->cl_discrtry) 1693 xprt_conditional_disconnect(task->tk_xprt, 1694 req->rq_connect_cookie); 1695 } 1696 } 1697 1698 static __be32 * 1699 rpc_encode_header(struct rpc_task *task) 1700 { 1701 struct rpc_clnt *clnt = task->tk_client; 1702 struct rpc_rqst *req = task->tk_rqstp; 1703 __be32 *p = req->rq_svec[0].iov_base; 1704 1705 /* FIXME: check buffer size? */ 1706 1707 p = xprt_skip_transport_header(task->tk_xprt, p); 1708 *p++ = req->rq_xid; /* XID */ 1709 *p++ = htonl(RPC_CALL); /* CALL */ 1710 *p++ = htonl(RPC_VERSION); /* RPC version */ 1711 *p++ = htonl(clnt->cl_prog); /* program number */ 1712 *p++ = htonl(clnt->cl_vers); /* program version */ 1713 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1714 p = rpcauth_marshcred(task, p); 1715 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1716 return p; 1717 } 1718 1719 static __be32 * 1720 rpc_verify_header(struct rpc_task *task) 1721 { 1722 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1723 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1724 __be32 *p = iov->iov_base; 1725 u32 n; 1726 int error = -EACCES; 1727 1728 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 1729 /* RFC-1014 says that the representation of XDR data must be a 1730 * multiple of four bytes 1731 * - if it isn't pointer subtraction in the NFS client may give 1732 * undefined results 1733 */ 1734 dprintk("RPC: %5u %s: XDR representation not a multiple of" 1735 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 1736 task->tk_rqstp->rq_rcv_buf.len); 1737 goto out_eio; 1738 } 1739 if ((len -= 3) < 0) 1740 goto out_overflow; 1741 1742 p += 1; /* skip XID */ 1743 if ((n = ntohl(*p++)) != RPC_REPLY) { 1744 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 1745 task->tk_pid, __func__, n); 1746 goto out_garbage; 1747 } 1748 1749 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1750 if (--len < 0) 1751 goto out_overflow; 1752 switch ((n = ntohl(*p++))) { 1753 case RPC_AUTH_ERROR: 1754 break; 1755 case RPC_MISMATCH: 1756 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 1757 task->tk_pid, __func__); 1758 error = -EPROTONOSUPPORT; 1759 goto out_err; 1760 default: 1761 dprintk("RPC: %5u %s: RPC call rejected, " 1762 "unknown error: %x\n", 1763 task->tk_pid, __func__, n); 1764 goto out_eio; 1765 } 1766 if (--len < 0) 1767 goto out_overflow; 1768 switch ((n = ntohl(*p++))) { 1769 case RPC_AUTH_REJECTEDCRED: 1770 case RPC_AUTH_REJECTEDVERF: 1771 case RPCSEC_GSS_CREDPROBLEM: 1772 case RPCSEC_GSS_CTXPROBLEM: 1773 if (!task->tk_cred_retry) 1774 break; 1775 task->tk_cred_retry--; 1776 dprintk("RPC: %5u %s: retry stale creds\n", 1777 task->tk_pid, __func__); 1778 rpcauth_invalcred(task); 1779 /* Ensure we obtain a new XID! */ 1780 xprt_release(task); 1781 task->tk_action = call_reserve; 1782 goto out_retry; 1783 case RPC_AUTH_BADCRED: 1784 case RPC_AUTH_BADVERF: 1785 /* possibly garbled cred/verf? */ 1786 if (!task->tk_garb_retry) 1787 break; 1788 task->tk_garb_retry--; 1789 dprintk("RPC: %5u %s: retry garbled creds\n", 1790 task->tk_pid, __func__); 1791 task->tk_action = call_bind; 1792 goto out_retry; 1793 case RPC_AUTH_TOOWEAK: 1794 printk(KERN_NOTICE "RPC: server %s requires stronger " 1795 "authentication.\n", task->tk_client->cl_server); 1796 break; 1797 default: 1798 dprintk("RPC: %5u %s: unknown auth error: %x\n", 1799 task->tk_pid, __func__, n); 1800 error = -EIO; 1801 } 1802 dprintk("RPC: %5u %s: call rejected %d\n", 1803 task->tk_pid, __func__, n); 1804 goto out_err; 1805 } 1806 if (!(p = rpcauth_checkverf(task, p))) { 1807 dprintk("RPC: %5u %s: auth check failed\n", 1808 task->tk_pid, __func__); 1809 goto out_garbage; /* bad verifier, retry */ 1810 } 1811 len = p - (__be32 *)iov->iov_base - 1; 1812 if (len < 0) 1813 goto out_overflow; 1814 switch ((n = ntohl(*p++))) { 1815 case RPC_SUCCESS: 1816 return p; 1817 case RPC_PROG_UNAVAIL: 1818 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", 1819 task->tk_pid, __func__, 1820 (unsigned int)task->tk_client->cl_prog, 1821 task->tk_client->cl_server); 1822 error = -EPFNOSUPPORT; 1823 goto out_err; 1824 case RPC_PROG_MISMATCH: 1825 dprintk("RPC: %5u %s: program %u, version %u unsupported by " 1826 "server %s\n", task->tk_pid, __func__, 1827 (unsigned int)task->tk_client->cl_prog, 1828 (unsigned int)task->tk_client->cl_vers, 1829 task->tk_client->cl_server); 1830 error = -EPROTONOSUPPORT; 1831 goto out_err; 1832 case RPC_PROC_UNAVAIL: 1833 dprintk("RPC: %5u %s: proc %s unsupported by program %u, " 1834 "version %u on server %s\n", 1835 task->tk_pid, __func__, 1836 rpc_proc_name(task), 1837 task->tk_client->cl_prog, 1838 task->tk_client->cl_vers, 1839 task->tk_client->cl_server); 1840 error = -EOPNOTSUPP; 1841 goto out_err; 1842 case RPC_GARBAGE_ARGS: 1843 dprintk("RPC: %5u %s: server saw garbage\n", 1844 task->tk_pid, __func__); 1845 break; /* retry */ 1846 default: 1847 dprintk("RPC: %5u %s: server accept status: %x\n", 1848 task->tk_pid, __func__, n); 1849 /* Also retry */ 1850 } 1851 1852 out_garbage: 1853 task->tk_client->cl_stats->rpcgarbage++; 1854 if (task->tk_garb_retry) { 1855 task->tk_garb_retry--; 1856 dprintk("RPC: %5u %s: retrying\n", 1857 task->tk_pid, __func__); 1858 task->tk_action = call_bind; 1859 out_retry: 1860 return ERR_PTR(-EAGAIN); 1861 } 1862 out_eio: 1863 error = -EIO; 1864 out_err: 1865 rpc_exit(task, error); 1866 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 1867 __func__, error); 1868 return ERR_PTR(error); 1869 out_overflow: 1870 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 1871 __func__); 1872 goto out_garbage; 1873 } 1874 1875 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 1876 { 1877 } 1878 1879 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 1880 { 1881 return 0; 1882 } 1883 1884 static struct rpc_procinfo rpcproc_null = { 1885 .p_encode = rpcproc_encode_null, 1886 .p_decode = rpcproc_decode_null, 1887 }; 1888 1889 static int rpc_ping(struct rpc_clnt *clnt) 1890 { 1891 struct rpc_message msg = { 1892 .rpc_proc = &rpcproc_null, 1893 }; 1894 int err; 1895 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1896 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 1897 put_rpccred(msg.rpc_cred); 1898 return err; 1899 } 1900 1901 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 1902 { 1903 struct rpc_message msg = { 1904 .rpc_proc = &rpcproc_null, 1905 .rpc_cred = cred, 1906 }; 1907 struct rpc_task_setup task_setup_data = { 1908 .rpc_client = clnt, 1909 .rpc_message = &msg, 1910 .callback_ops = &rpc_default_ops, 1911 .flags = flags, 1912 }; 1913 return rpc_run_task(&task_setup_data); 1914 } 1915 EXPORT_SYMBOL_GPL(rpc_call_null); 1916 1917 #ifdef RPC_DEBUG 1918 static void rpc_show_header(void) 1919 { 1920 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 1921 "-timeout ---ops--\n"); 1922 } 1923 1924 static void rpc_show_task(const struct rpc_clnt *clnt, 1925 const struct rpc_task *task) 1926 { 1927 const char *rpc_waitq = "none"; 1928 1929 if (RPC_IS_QUEUED(task)) 1930 rpc_waitq = rpc_qname(task->tk_waitqueue); 1931 1932 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 1933 task->tk_pid, task->tk_flags, task->tk_status, 1934 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 1935 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task), 1936 task->tk_action, rpc_waitq); 1937 } 1938 1939 void rpc_show_tasks(struct net *net) 1940 { 1941 struct rpc_clnt *clnt; 1942 struct rpc_task *task; 1943 int header = 0; 1944 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1945 1946 spin_lock(&sn->rpc_client_lock); 1947 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 1948 spin_lock(&clnt->cl_lock); 1949 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 1950 if (!header) { 1951 rpc_show_header(); 1952 header++; 1953 } 1954 rpc_show_task(clnt, task); 1955 } 1956 spin_unlock(&clnt->cl_lock); 1957 } 1958 spin_unlock(&sn->rpc_client_lock); 1959 } 1960 #endif 1961