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 21 #include <linux/module.h> 22 #include <linux/types.h> 23 #include <linux/kallsyms.h> 24 #include <linux/mm.h> 25 #include <linux/namei.h> 26 #include <linux/mount.h> 27 #include <linux/slab.h> 28 #include <linux/utsname.h> 29 #include <linux/workqueue.h> 30 #include <linux/in.h> 31 #include <linux/in6.h> 32 #include <linux/un.h> 33 #include <linux/rcupdate.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 #include <trace/events/sunrpc.h> 40 41 #include "sunrpc.h" 42 #include "netns.h" 43 44 #ifdef RPC_DEBUG 45 # define RPCDBG_FACILITY RPCDBG_CALL 46 #endif 47 48 #define dprint_status(t) \ 49 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 50 __func__, t->tk_status) 51 52 /* 53 * All RPC clients are linked into this list 54 */ 55 56 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 57 58 59 static void call_start(struct rpc_task *task); 60 static void call_reserve(struct rpc_task *task); 61 static void call_reserveresult(struct rpc_task *task); 62 static void call_allocate(struct rpc_task *task); 63 static void call_decode(struct rpc_task *task); 64 static void call_bind(struct rpc_task *task); 65 static void call_bind_status(struct rpc_task *task); 66 static void call_transmit(struct rpc_task *task); 67 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 68 static void call_bc_transmit(struct rpc_task *task); 69 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 70 static void call_status(struct rpc_task *task); 71 static void call_transmit_status(struct rpc_task *task); 72 static void call_refresh(struct rpc_task *task); 73 static void call_refreshresult(struct rpc_task *task); 74 static void call_timeout(struct rpc_task *task); 75 static void call_connect(struct rpc_task *task); 76 static void call_connect_status(struct rpc_task *task); 77 78 static __be32 *rpc_encode_header(struct rpc_task *task); 79 static __be32 *rpc_verify_header(struct rpc_task *task); 80 static int rpc_ping(struct rpc_clnt *clnt); 81 82 static void rpc_register_client(struct rpc_clnt *clnt) 83 { 84 struct net *net = rpc_net_ns(clnt); 85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 86 87 spin_lock(&sn->rpc_client_lock); 88 list_add(&clnt->cl_clients, &sn->all_clients); 89 spin_unlock(&sn->rpc_client_lock); 90 } 91 92 static void rpc_unregister_client(struct rpc_clnt *clnt) 93 { 94 struct net *net = rpc_net_ns(clnt); 95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 96 97 spin_lock(&sn->rpc_client_lock); 98 list_del(&clnt->cl_clients); 99 spin_unlock(&sn->rpc_client_lock); 100 } 101 102 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 103 { 104 if (clnt->cl_dentry) { 105 if (clnt->cl_auth && clnt->cl_auth->au_ops->pipes_destroy) 106 clnt->cl_auth->au_ops->pipes_destroy(clnt->cl_auth); 107 rpc_remove_client_dir(clnt->cl_dentry); 108 } 109 clnt->cl_dentry = NULL; 110 } 111 112 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 113 { 114 struct net *net = rpc_net_ns(clnt); 115 struct super_block *pipefs_sb; 116 117 pipefs_sb = rpc_get_sb_net(net); 118 if (pipefs_sb) { 119 __rpc_clnt_remove_pipedir(clnt); 120 rpc_put_sb_net(net); 121 } 122 } 123 124 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 125 struct rpc_clnt *clnt, 126 const char *dir_name) 127 { 128 static uint32_t clntid; 129 char name[15]; 130 struct qstr q = { .name = name }; 131 struct dentry *dir, *dentry; 132 int error; 133 134 dir = rpc_d_lookup_sb(sb, dir_name); 135 if (dir == NULL) { 136 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 137 return dir; 138 } 139 for (;;) { 140 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 141 name[sizeof(name) - 1] = '\0'; 142 q.hash = full_name_hash(q.name, q.len); 143 dentry = rpc_create_client_dir(dir, &q, clnt); 144 if (!IS_ERR(dentry)) 145 break; 146 error = PTR_ERR(dentry); 147 if (error != -EEXIST) { 148 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 149 " %s/%s, error %d\n", 150 dir_name, name, error); 151 break; 152 } 153 } 154 dput(dir); 155 return dentry; 156 } 157 158 static int 159 rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name) 160 { 161 struct net *net = rpc_net_ns(clnt); 162 struct super_block *pipefs_sb; 163 struct dentry *dentry; 164 165 clnt->cl_dentry = NULL; 166 if (dir_name == NULL) 167 return 0; 168 pipefs_sb = rpc_get_sb_net(net); 169 if (!pipefs_sb) 170 return 0; 171 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt, dir_name); 172 rpc_put_sb_net(net); 173 if (IS_ERR(dentry)) 174 return PTR_ERR(dentry); 175 clnt->cl_dentry = dentry; 176 return 0; 177 } 178 179 static inline int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 180 { 181 if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) || 182 ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry)) 183 return 1; 184 return 0; 185 } 186 187 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 188 struct super_block *sb) 189 { 190 struct dentry *dentry; 191 int err = 0; 192 193 switch (event) { 194 case RPC_PIPEFS_MOUNT: 195 dentry = rpc_setup_pipedir_sb(sb, clnt, 196 clnt->cl_program->pipe_dir_name); 197 if (!dentry) 198 return -ENOENT; 199 if (IS_ERR(dentry)) 200 return PTR_ERR(dentry); 201 clnt->cl_dentry = dentry; 202 if (clnt->cl_auth->au_ops->pipes_create) { 203 err = clnt->cl_auth->au_ops->pipes_create(clnt->cl_auth); 204 if (err) 205 __rpc_clnt_remove_pipedir(clnt); 206 } 207 break; 208 case RPC_PIPEFS_UMOUNT: 209 __rpc_clnt_remove_pipedir(clnt); 210 break; 211 default: 212 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 213 return -ENOTSUPP; 214 } 215 return err; 216 } 217 218 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 219 struct super_block *sb) 220 { 221 int error = 0; 222 223 for (;; clnt = clnt->cl_parent) { 224 if (!rpc_clnt_skip_event(clnt, event)) 225 error = __rpc_clnt_handle_event(clnt, event, sb); 226 if (error || clnt == clnt->cl_parent) 227 break; 228 } 229 return error; 230 } 231 232 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 233 { 234 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 235 struct rpc_clnt *clnt; 236 237 spin_lock(&sn->rpc_client_lock); 238 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 239 if (clnt->cl_program->pipe_dir_name == NULL) 240 continue; 241 if (rpc_clnt_skip_event(clnt, event)) 242 continue; 243 if (atomic_inc_not_zero(&clnt->cl_count) == 0) 244 continue; 245 spin_unlock(&sn->rpc_client_lock); 246 return clnt; 247 } 248 spin_unlock(&sn->rpc_client_lock); 249 return NULL; 250 } 251 252 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 253 void *ptr) 254 { 255 struct super_block *sb = ptr; 256 struct rpc_clnt *clnt; 257 int error = 0; 258 259 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 260 error = __rpc_pipefs_event(clnt, event, sb); 261 rpc_release_client(clnt); 262 if (error) 263 break; 264 } 265 return error; 266 } 267 268 static struct notifier_block rpc_clients_block = { 269 .notifier_call = rpc_pipefs_event, 270 .priority = SUNRPC_PIPEFS_RPC_PRIO, 271 }; 272 273 int rpc_clients_notifier_register(void) 274 { 275 return rpc_pipefs_notifier_register(&rpc_clients_block); 276 } 277 278 void rpc_clients_notifier_unregister(void) 279 { 280 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 281 } 282 283 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 284 { 285 clnt->cl_nodelen = strlen(nodename); 286 if (clnt->cl_nodelen > UNX_MAXNODENAME) 287 clnt->cl_nodelen = UNX_MAXNODENAME; 288 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen); 289 } 290 291 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt) 292 { 293 const struct rpc_program *program = args->program; 294 const struct rpc_version *version; 295 struct rpc_clnt *clnt = NULL; 296 struct rpc_auth *auth; 297 int err; 298 299 /* sanity check the name before trying to print it */ 300 dprintk("RPC: creating %s client for %s (xprt %p)\n", 301 program->name, args->servername, xprt); 302 303 err = rpciod_up(); 304 if (err) 305 goto out_no_rpciod; 306 err = -EINVAL; 307 if (!xprt) 308 goto out_no_xprt; 309 310 if (args->version >= program->nrvers) 311 goto out_err; 312 version = program->version[args->version]; 313 if (version == NULL) 314 goto out_err; 315 316 err = -ENOMEM; 317 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 318 if (!clnt) 319 goto out_err; 320 clnt->cl_parent = clnt; 321 322 rcu_assign_pointer(clnt->cl_xprt, xprt); 323 clnt->cl_procinfo = version->procs; 324 clnt->cl_maxproc = version->nrprocs; 325 clnt->cl_protname = program->name; 326 clnt->cl_prog = args->prognumber ? : program->number; 327 clnt->cl_vers = version->number; 328 clnt->cl_stats = program->stats; 329 clnt->cl_metrics = rpc_alloc_iostats(clnt); 330 err = -ENOMEM; 331 if (clnt->cl_metrics == NULL) 332 goto out_no_stats; 333 clnt->cl_program = program; 334 INIT_LIST_HEAD(&clnt->cl_tasks); 335 spin_lock_init(&clnt->cl_lock); 336 337 if (!xprt_bound(xprt)) 338 clnt->cl_autobind = 1; 339 340 clnt->cl_timeout = xprt->timeout; 341 if (args->timeout != NULL) { 342 memcpy(&clnt->cl_timeout_default, args->timeout, 343 sizeof(clnt->cl_timeout_default)); 344 clnt->cl_timeout = &clnt->cl_timeout_default; 345 } 346 347 clnt->cl_rtt = &clnt->cl_rtt_default; 348 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 349 clnt->cl_principal = NULL; 350 if (args->client_name) { 351 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL); 352 if (!clnt->cl_principal) 353 goto out_no_principal; 354 } 355 356 atomic_set(&clnt->cl_count, 1); 357 358 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 359 if (err < 0) 360 goto out_no_path; 361 362 auth = rpcauth_create(args->authflavor, clnt); 363 if (IS_ERR(auth)) { 364 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 365 args->authflavor); 366 err = PTR_ERR(auth); 367 goto out_no_auth; 368 } 369 370 /* save the nodename */ 371 rpc_clnt_set_nodename(clnt, utsname()->nodename); 372 rpc_register_client(clnt); 373 return clnt; 374 375 out_no_auth: 376 rpc_clnt_remove_pipedir(clnt); 377 out_no_path: 378 kfree(clnt->cl_principal); 379 out_no_principal: 380 rpc_free_iostats(clnt->cl_metrics); 381 out_no_stats: 382 kfree(clnt); 383 out_err: 384 xprt_put(xprt); 385 out_no_xprt: 386 rpciod_down(); 387 out_no_rpciod: 388 return ERR_PTR(err); 389 } 390 391 /** 392 * rpc_create - create an RPC client and transport with one call 393 * @args: rpc_clnt create argument structure 394 * 395 * Creates and initializes an RPC transport and an RPC client. 396 * 397 * It can ping the server in order to determine if it is up, and to see if 398 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 399 * this behavior so asynchronous tasks can also use rpc_create. 400 */ 401 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 402 { 403 struct rpc_xprt *xprt; 404 struct rpc_clnt *clnt; 405 struct xprt_create xprtargs = { 406 .net = args->net, 407 .ident = args->protocol, 408 .srcaddr = args->saddress, 409 .dstaddr = args->address, 410 .addrlen = args->addrsize, 411 .servername = args->servername, 412 .bc_xprt = args->bc_xprt, 413 }; 414 char servername[48]; 415 416 /* 417 * If the caller chooses not to specify a hostname, whip 418 * up a string representation of the passed-in address. 419 */ 420 if (xprtargs.servername == NULL) { 421 struct sockaddr_un *sun = 422 (struct sockaddr_un *)args->address; 423 struct sockaddr_in *sin = 424 (struct sockaddr_in *)args->address; 425 struct sockaddr_in6 *sin6 = 426 (struct sockaddr_in6 *)args->address; 427 428 servername[0] = '\0'; 429 switch (args->address->sa_family) { 430 case AF_LOCAL: 431 snprintf(servername, sizeof(servername), "%s", 432 sun->sun_path); 433 break; 434 case AF_INET: 435 snprintf(servername, sizeof(servername), "%pI4", 436 &sin->sin_addr.s_addr); 437 break; 438 case AF_INET6: 439 snprintf(servername, sizeof(servername), "%pI6", 440 &sin6->sin6_addr); 441 break; 442 default: 443 /* caller wants default server name, but 444 * address family isn't recognized. */ 445 return ERR_PTR(-EINVAL); 446 } 447 xprtargs.servername = servername; 448 } 449 450 xprt = xprt_create_transport(&xprtargs); 451 if (IS_ERR(xprt)) 452 return (struct rpc_clnt *)xprt; 453 454 /* 455 * By default, kernel RPC client connects from a reserved port. 456 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 457 * but it is always enabled for rpciod, which handles the connect 458 * operation. 459 */ 460 xprt->resvport = 1; 461 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 462 xprt->resvport = 0; 463 464 clnt = rpc_new_client(args, xprt); 465 if (IS_ERR(clnt)) 466 return clnt; 467 468 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 469 int err = rpc_ping(clnt); 470 if (err != 0) { 471 rpc_shutdown_client(clnt); 472 return ERR_PTR(err); 473 } 474 } 475 476 clnt->cl_softrtry = 1; 477 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 478 clnt->cl_softrtry = 0; 479 480 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 481 clnt->cl_autobind = 1; 482 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 483 clnt->cl_discrtry = 1; 484 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 485 clnt->cl_chatty = 1; 486 487 return clnt; 488 } 489 EXPORT_SYMBOL_GPL(rpc_create); 490 491 /* 492 * This function clones the RPC client structure. It allows us to share the 493 * same transport while varying parameters such as the authentication 494 * flavour. 495 */ 496 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 497 struct rpc_clnt *clnt) 498 { 499 struct rpc_xprt *xprt; 500 struct rpc_clnt *new; 501 int err; 502 503 err = -ENOMEM; 504 rcu_read_lock(); 505 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 506 rcu_read_unlock(); 507 if (xprt == NULL) 508 goto out_err; 509 args->servername = xprt->servername; 510 511 new = rpc_new_client(args, xprt); 512 if (IS_ERR(new)) { 513 err = PTR_ERR(new); 514 goto out_put; 515 } 516 517 atomic_inc(&clnt->cl_count); 518 new->cl_parent = clnt; 519 520 /* Turn off autobind on clones */ 521 new->cl_autobind = 0; 522 new->cl_softrtry = clnt->cl_softrtry; 523 new->cl_discrtry = clnt->cl_discrtry; 524 new->cl_chatty = clnt->cl_chatty; 525 return new; 526 527 out_put: 528 xprt_put(xprt); 529 out_err: 530 dprintk("RPC: %s: returned error %d\n", __func__, err); 531 return ERR_PTR(err); 532 } 533 534 /** 535 * rpc_clone_client - Clone an RPC client structure 536 * 537 * @clnt: RPC client whose parameters are copied 538 * 539 * Returns a fresh RPC client or an ERR_PTR. 540 */ 541 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 542 { 543 struct rpc_create_args args = { 544 .program = clnt->cl_program, 545 .prognumber = clnt->cl_prog, 546 .version = clnt->cl_vers, 547 .authflavor = clnt->cl_auth->au_flavor, 548 .client_name = clnt->cl_principal, 549 }; 550 return __rpc_clone_client(&args, clnt); 551 } 552 EXPORT_SYMBOL_GPL(rpc_clone_client); 553 554 /** 555 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 556 * 557 * @clnt: RPC client whose parameters are copied 558 * @auth: security flavor for new client 559 * 560 * Returns a fresh RPC client or an ERR_PTR. 561 */ 562 struct rpc_clnt * 563 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 564 { 565 struct rpc_create_args args = { 566 .program = clnt->cl_program, 567 .prognumber = clnt->cl_prog, 568 .version = clnt->cl_vers, 569 .authflavor = flavor, 570 .client_name = clnt->cl_principal, 571 }; 572 return __rpc_clone_client(&args, clnt); 573 } 574 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 575 576 /* 577 * Kill all tasks for the given client. 578 * XXX: kill their descendants as well? 579 */ 580 void rpc_killall_tasks(struct rpc_clnt *clnt) 581 { 582 struct rpc_task *rovr; 583 584 585 if (list_empty(&clnt->cl_tasks)) 586 return; 587 dprintk("RPC: killing all tasks for client %p\n", clnt); 588 /* 589 * Spin lock all_tasks to prevent changes... 590 */ 591 spin_lock(&clnt->cl_lock); 592 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 593 if (!RPC_IS_ACTIVATED(rovr)) 594 continue; 595 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 596 rovr->tk_flags |= RPC_TASK_KILLED; 597 rpc_exit(rovr, -EIO); 598 if (RPC_IS_QUEUED(rovr)) 599 rpc_wake_up_queued_task(rovr->tk_waitqueue, 600 rovr); 601 } 602 } 603 spin_unlock(&clnt->cl_lock); 604 } 605 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 606 607 /* 608 * Properly shut down an RPC client, terminating all outstanding 609 * requests. 610 */ 611 void rpc_shutdown_client(struct rpc_clnt *clnt) 612 { 613 /* 614 * To avoid deadlock, never call rpc_shutdown_client from a 615 * workqueue context! 616 */ 617 WARN_ON_ONCE(current->flags & PF_WQ_WORKER); 618 might_sleep(); 619 620 dprintk_rcu("RPC: shutting down %s client for %s\n", 621 clnt->cl_protname, 622 rcu_dereference(clnt->cl_xprt)->servername); 623 624 while (!list_empty(&clnt->cl_tasks)) { 625 rpc_killall_tasks(clnt); 626 wait_event_timeout(destroy_wait, 627 list_empty(&clnt->cl_tasks), 1*HZ); 628 } 629 630 rpc_release_client(clnt); 631 } 632 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 633 634 /* 635 * Free an RPC client 636 */ 637 static void 638 rpc_free_client(struct rpc_clnt *clnt) 639 { 640 dprintk_rcu("RPC: destroying %s client for %s\n", 641 clnt->cl_protname, 642 rcu_dereference(clnt->cl_xprt)->servername); 643 if (clnt->cl_parent != clnt) 644 rpc_release_client(clnt->cl_parent); 645 rpc_unregister_client(clnt); 646 rpc_clnt_remove_pipedir(clnt); 647 rpc_free_iostats(clnt->cl_metrics); 648 kfree(clnt->cl_principal); 649 clnt->cl_metrics = NULL; 650 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 651 rpciod_down(); 652 kfree(clnt); 653 } 654 655 /* 656 * Free an RPC client 657 */ 658 static void 659 rpc_free_auth(struct rpc_clnt *clnt) 660 { 661 if (clnt->cl_auth == NULL) { 662 rpc_free_client(clnt); 663 return; 664 } 665 666 /* 667 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 668 * release remaining GSS contexts. This mechanism ensures 669 * that it can do so safely. 670 */ 671 atomic_inc(&clnt->cl_count); 672 rpcauth_release(clnt->cl_auth); 673 clnt->cl_auth = NULL; 674 if (atomic_dec_and_test(&clnt->cl_count)) 675 rpc_free_client(clnt); 676 } 677 678 /* 679 * Release reference to the RPC client 680 */ 681 void 682 rpc_release_client(struct rpc_clnt *clnt) 683 { 684 dprintk("RPC: rpc_release_client(%p)\n", clnt); 685 686 if (list_empty(&clnt->cl_tasks)) 687 wake_up(&destroy_wait); 688 if (atomic_dec_and_test(&clnt->cl_count)) 689 rpc_free_auth(clnt); 690 } 691 692 /** 693 * rpc_bind_new_program - bind a new RPC program to an existing client 694 * @old: old rpc_client 695 * @program: rpc program to set 696 * @vers: rpc program version 697 * 698 * Clones the rpc client and sets up a new RPC program. This is mainly 699 * of use for enabling different RPC programs to share the same transport. 700 * The Sun NFSv2/v3 ACL protocol can do this. 701 */ 702 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 703 const struct rpc_program *program, 704 u32 vers) 705 { 706 struct rpc_create_args args = { 707 .program = program, 708 .prognumber = program->number, 709 .version = vers, 710 .authflavor = old->cl_auth->au_flavor, 711 .client_name = old->cl_principal, 712 }; 713 struct rpc_clnt *clnt; 714 int err; 715 716 clnt = __rpc_clone_client(&args, old); 717 if (IS_ERR(clnt)) 718 goto out; 719 err = rpc_ping(clnt); 720 if (err != 0) { 721 rpc_shutdown_client(clnt); 722 clnt = ERR_PTR(err); 723 } 724 out: 725 return clnt; 726 } 727 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 728 729 void rpc_task_release_client(struct rpc_task *task) 730 { 731 struct rpc_clnt *clnt = task->tk_client; 732 733 if (clnt != NULL) { 734 /* Remove from client task list */ 735 spin_lock(&clnt->cl_lock); 736 list_del(&task->tk_task); 737 spin_unlock(&clnt->cl_lock); 738 task->tk_client = NULL; 739 740 rpc_release_client(clnt); 741 } 742 } 743 744 static 745 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 746 { 747 if (clnt != NULL) { 748 rpc_task_release_client(task); 749 task->tk_client = clnt; 750 atomic_inc(&clnt->cl_count); 751 if (clnt->cl_softrtry) 752 task->tk_flags |= RPC_TASK_SOFT; 753 if (sk_memalloc_socks()) { 754 struct rpc_xprt *xprt; 755 756 rcu_read_lock(); 757 xprt = rcu_dereference(clnt->cl_xprt); 758 if (xprt->swapper) 759 task->tk_flags |= RPC_TASK_SWAPPER; 760 rcu_read_unlock(); 761 } 762 /* Add to the client's list of all tasks */ 763 spin_lock(&clnt->cl_lock); 764 list_add_tail(&task->tk_task, &clnt->cl_tasks); 765 spin_unlock(&clnt->cl_lock); 766 } 767 } 768 769 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) 770 { 771 rpc_task_release_client(task); 772 rpc_task_set_client(task, clnt); 773 } 774 EXPORT_SYMBOL_GPL(rpc_task_reset_client); 775 776 777 static void 778 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 779 { 780 if (msg != NULL) { 781 task->tk_msg.rpc_proc = msg->rpc_proc; 782 task->tk_msg.rpc_argp = msg->rpc_argp; 783 task->tk_msg.rpc_resp = msg->rpc_resp; 784 if (msg->rpc_cred != NULL) 785 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 786 } 787 } 788 789 /* 790 * Default callback for async RPC calls 791 */ 792 static void 793 rpc_default_callback(struct rpc_task *task, void *data) 794 { 795 } 796 797 static const struct rpc_call_ops rpc_default_ops = { 798 .rpc_call_done = rpc_default_callback, 799 }; 800 801 /** 802 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 803 * @task_setup_data: pointer to task initialisation data 804 */ 805 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 806 { 807 struct rpc_task *task; 808 809 task = rpc_new_task(task_setup_data); 810 if (IS_ERR(task)) 811 goto out; 812 813 rpc_task_set_client(task, task_setup_data->rpc_client); 814 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 815 816 if (task->tk_action == NULL) 817 rpc_call_start(task); 818 819 atomic_inc(&task->tk_count); 820 rpc_execute(task); 821 out: 822 return task; 823 } 824 EXPORT_SYMBOL_GPL(rpc_run_task); 825 826 /** 827 * rpc_call_sync - Perform a synchronous RPC call 828 * @clnt: pointer to RPC client 829 * @msg: RPC call parameters 830 * @flags: RPC call flags 831 */ 832 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 833 { 834 struct rpc_task *task; 835 struct rpc_task_setup task_setup_data = { 836 .rpc_client = clnt, 837 .rpc_message = msg, 838 .callback_ops = &rpc_default_ops, 839 .flags = flags, 840 }; 841 int status; 842 843 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 844 if (flags & RPC_TASK_ASYNC) { 845 rpc_release_calldata(task_setup_data.callback_ops, 846 task_setup_data.callback_data); 847 return -EINVAL; 848 } 849 850 task = rpc_run_task(&task_setup_data); 851 if (IS_ERR(task)) 852 return PTR_ERR(task); 853 status = task->tk_status; 854 rpc_put_task(task); 855 return status; 856 } 857 EXPORT_SYMBOL_GPL(rpc_call_sync); 858 859 /** 860 * rpc_call_async - Perform an asynchronous RPC call 861 * @clnt: pointer to RPC client 862 * @msg: RPC call parameters 863 * @flags: RPC call flags 864 * @tk_ops: RPC call ops 865 * @data: user call data 866 */ 867 int 868 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 869 const struct rpc_call_ops *tk_ops, void *data) 870 { 871 struct rpc_task *task; 872 struct rpc_task_setup task_setup_data = { 873 .rpc_client = clnt, 874 .rpc_message = msg, 875 .callback_ops = tk_ops, 876 .callback_data = data, 877 .flags = flags|RPC_TASK_ASYNC, 878 }; 879 880 task = rpc_run_task(&task_setup_data); 881 if (IS_ERR(task)) 882 return PTR_ERR(task); 883 rpc_put_task(task); 884 return 0; 885 } 886 EXPORT_SYMBOL_GPL(rpc_call_async); 887 888 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 889 /** 890 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 891 * rpc_execute against it 892 * @req: RPC request 893 * @tk_ops: RPC call ops 894 */ 895 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 896 const struct rpc_call_ops *tk_ops) 897 { 898 struct rpc_task *task; 899 struct xdr_buf *xbufp = &req->rq_snd_buf; 900 struct rpc_task_setup task_setup_data = { 901 .callback_ops = tk_ops, 902 }; 903 904 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 905 /* 906 * Create an rpc_task to send the data 907 */ 908 task = rpc_new_task(&task_setup_data); 909 if (IS_ERR(task)) { 910 xprt_free_bc_request(req); 911 goto out; 912 } 913 task->tk_rqstp = req; 914 915 /* 916 * Set up the xdr_buf length. 917 * This also indicates that the buffer is XDR encoded already. 918 */ 919 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 920 xbufp->tail[0].iov_len; 921 922 task->tk_action = call_bc_transmit; 923 atomic_inc(&task->tk_count); 924 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 925 rpc_execute(task); 926 927 out: 928 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 929 return task; 930 } 931 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 932 933 void 934 rpc_call_start(struct rpc_task *task) 935 { 936 task->tk_action = call_start; 937 } 938 EXPORT_SYMBOL_GPL(rpc_call_start); 939 940 /** 941 * rpc_peeraddr - extract remote peer address from clnt's xprt 942 * @clnt: RPC client structure 943 * @buf: target buffer 944 * @bufsize: length of target buffer 945 * 946 * Returns the number of bytes that are actually in the stored address. 947 */ 948 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 949 { 950 size_t bytes; 951 struct rpc_xprt *xprt; 952 953 rcu_read_lock(); 954 xprt = rcu_dereference(clnt->cl_xprt); 955 956 bytes = xprt->addrlen; 957 if (bytes > bufsize) 958 bytes = bufsize; 959 memcpy(buf, &xprt->addr, bytes); 960 rcu_read_unlock(); 961 962 return bytes; 963 } 964 EXPORT_SYMBOL_GPL(rpc_peeraddr); 965 966 /** 967 * rpc_peeraddr2str - return remote peer address in printable format 968 * @clnt: RPC client structure 969 * @format: address format 970 * 971 * NB: the lifetime of the memory referenced by the returned pointer is 972 * the same as the rpc_xprt itself. As long as the caller uses this 973 * pointer, it must hold the RCU read lock. 974 */ 975 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 976 enum rpc_display_format_t format) 977 { 978 struct rpc_xprt *xprt; 979 980 xprt = rcu_dereference(clnt->cl_xprt); 981 982 if (xprt->address_strings[format] != NULL) 983 return xprt->address_strings[format]; 984 else 985 return "unprintable"; 986 } 987 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 988 989 static const struct sockaddr_in rpc_inaddr_loopback = { 990 .sin_family = AF_INET, 991 .sin_addr.s_addr = htonl(INADDR_ANY), 992 }; 993 994 static const struct sockaddr_in6 rpc_in6addr_loopback = { 995 .sin6_family = AF_INET6, 996 .sin6_addr = IN6ADDR_ANY_INIT, 997 }; 998 999 /* 1000 * Try a getsockname() on a connected datagram socket. Using a 1001 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1002 * This conserves the ephemeral port number space. 1003 * 1004 * Returns zero and fills in "buf" if successful; otherwise, a 1005 * negative errno is returned. 1006 */ 1007 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1008 struct sockaddr *buf, int buflen) 1009 { 1010 struct socket *sock; 1011 int err; 1012 1013 err = __sock_create(net, sap->sa_family, 1014 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1015 if (err < 0) { 1016 dprintk("RPC: can't create UDP socket (%d)\n", err); 1017 goto out; 1018 } 1019 1020 switch (sap->sa_family) { 1021 case AF_INET: 1022 err = kernel_bind(sock, 1023 (struct sockaddr *)&rpc_inaddr_loopback, 1024 sizeof(rpc_inaddr_loopback)); 1025 break; 1026 case AF_INET6: 1027 err = kernel_bind(sock, 1028 (struct sockaddr *)&rpc_in6addr_loopback, 1029 sizeof(rpc_in6addr_loopback)); 1030 break; 1031 default: 1032 err = -EAFNOSUPPORT; 1033 goto out; 1034 } 1035 if (err < 0) { 1036 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1037 goto out_release; 1038 } 1039 1040 err = kernel_connect(sock, sap, salen, 0); 1041 if (err < 0) { 1042 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1043 goto out_release; 1044 } 1045 1046 err = kernel_getsockname(sock, buf, &buflen); 1047 if (err < 0) { 1048 dprintk("RPC: getsockname failed (%d)\n", err); 1049 goto out_release; 1050 } 1051 1052 err = 0; 1053 if (buf->sa_family == AF_INET6) { 1054 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1055 sin6->sin6_scope_id = 0; 1056 } 1057 dprintk("RPC: %s succeeded\n", __func__); 1058 1059 out_release: 1060 sock_release(sock); 1061 out: 1062 return err; 1063 } 1064 1065 /* 1066 * Scraping a connected socket failed, so we don't have a useable 1067 * local address. Fallback: generate an address that will prevent 1068 * the server from calling us back. 1069 * 1070 * Returns zero and fills in "buf" if successful; otherwise, a 1071 * negative errno is returned. 1072 */ 1073 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1074 { 1075 switch (family) { 1076 case AF_INET: 1077 if (buflen < sizeof(rpc_inaddr_loopback)) 1078 return -EINVAL; 1079 memcpy(buf, &rpc_inaddr_loopback, 1080 sizeof(rpc_inaddr_loopback)); 1081 break; 1082 case AF_INET6: 1083 if (buflen < sizeof(rpc_in6addr_loopback)) 1084 return -EINVAL; 1085 memcpy(buf, &rpc_in6addr_loopback, 1086 sizeof(rpc_in6addr_loopback)); 1087 default: 1088 dprintk("RPC: %s: address family not supported\n", 1089 __func__); 1090 return -EAFNOSUPPORT; 1091 } 1092 dprintk("RPC: %s: succeeded\n", __func__); 1093 return 0; 1094 } 1095 1096 /** 1097 * rpc_localaddr - discover local endpoint address for an RPC client 1098 * @clnt: RPC client structure 1099 * @buf: target buffer 1100 * @buflen: size of target buffer, in bytes 1101 * 1102 * Returns zero and fills in "buf" and "buflen" if successful; 1103 * otherwise, a negative errno is returned. 1104 * 1105 * This works even if the underlying transport is not currently connected, 1106 * or if the upper layer never previously provided a source address. 1107 * 1108 * The result of this function call is transient: multiple calls in 1109 * succession may give different results, depending on how local 1110 * networking configuration changes over time. 1111 */ 1112 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1113 { 1114 struct sockaddr_storage address; 1115 struct sockaddr *sap = (struct sockaddr *)&address; 1116 struct rpc_xprt *xprt; 1117 struct net *net; 1118 size_t salen; 1119 int err; 1120 1121 rcu_read_lock(); 1122 xprt = rcu_dereference(clnt->cl_xprt); 1123 salen = xprt->addrlen; 1124 memcpy(sap, &xprt->addr, salen); 1125 net = get_net(xprt->xprt_net); 1126 rcu_read_unlock(); 1127 1128 rpc_set_port(sap, 0); 1129 err = rpc_sockname(net, sap, salen, buf, buflen); 1130 put_net(net); 1131 if (err != 0) 1132 /* Couldn't discover local address, return ANYADDR */ 1133 return rpc_anyaddr(sap->sa_family, buf, buflen); 1134 return 0; 1135 } 1136 EXPORT_SYMBOL_GPL(rpc_localaddr); 1137 1138 void 1139 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1140 { 1141 struct rpc_xprt *xprt; 1142 1143 rcu_read_lock(); 1144 xprt = rcu_dereference(clnt->cl_xprt); 1145 if (xprt->ops->set_buffer_size) 1146 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1147 rcu_read_unlock(); 1148 } 1149 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1150 1151 /** 1152 * rpc_protocol - Get transport protocol number for an RPC client 1153 * @clnt: RPC client to query 1154 * 1155 */ 1156 int rpc_protocol(struct rpc_clnt *clnt) 1157 { 1158 int protocol; 1159 1160 rcu_read_lock(); 1161 protocol = rcu_dereference(clnt->cl_xprt)->prot; 1162 rcu_read_unlock(); 1163 return protocol; 1164 } 1165 EXPORT_SYMBOL_GPL(rpc_protocol); 1166 1167 /** 1168 * rpc_net_ns - Get the network namespace for this RPC client 1169 * @clnt: RPC client to query 1170 * 1171 */ 1172 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1173 { 1174 struct net *ret; 1175 1176 rcu_read_lock(); 1177 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1178 rcu_read_unlock(); 1179 return ret; 1180 } 1181 EXPORT_SYMBOL_GPL(rpc_net_ns); 1182 1183 /** 1184 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1185 * @clnt: RPC client to query 1186 * 1187 * For stream transports, this is one RPC record fragment (see RFC 1188 * 1831), as we don't support multi-record requests yet. For datagram 1189 * transports, this is the size of an IP packet minus the IP, UDP, and 1190 * RPC header sizes. 1191 */ 1192 size_t rpc_max_payload(struct rpc_clnt *clnt) 1193 { 1194 size_t ret; 1195 1196 rcu_read_lock(); 1197 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1198 rcu_read_unlock(); 1199 return ret; 1200 } 1201 EXPORT_SYMBOL_GPL(rpc_max_payload); 1202 1203 /** 1204 * rpc_force_rebind - force transport to check that remote port is unchanged 1205 * @clnt: client to rebind 1206 * 1207 */ 1208 void rpc_force_rebind(struct rpc_clnt *clnt) 1209 { 1210 if (clnt->cl_autobind) { 1211 rcu_read_lock(); 1212 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1213 rcu_read_unlock(); 1214 } 1215 } 1216 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1217 1218 /* 1219 * Restart an (async) RPC call from the call_prepare state. 1220 * Usually called from within the exit handler. 1221 */ 1222 int 1223 rpc_restart_call_prepare(struct rpc_task *task) 1224 { 1225 if (RPC_ASSASSINATED(task)) 1226 return 0; 1227 task->tk_action = call_start; 1228 if (task->tk_ops->rpc_call_prepare != NULL) 1229 task->tk_action = rpc_prepare_task; 1230 return 1; 1231 } 1232 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1233 1234 /* 1235 * Restart an (async) RPC call. Usually called from within the 1236 * exit handler. 1237 */ 1238 int 1239 rpc_restart_call(struct rpc_task *task) 1240 { 1241 if (RPC_ASSASSINATED(task)) 1242 return 0; 1243 task->tk_action = call_start; 1244 return 1; 1245 } 1246 EXPORT_SYMBOL_GPL(rpc_restart_call); 1247 1248 #ifdef RPC_DEBUG 1249 static const char *rpc_proc_name(const struct rpc_task *task) 1250 { 1251 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1252 1253 if (proc) { 1254 if (proc->p_name) 1255 return proc->p_name; 1256 else 1257 return "NULL"; 1258 } else 1259 return "no proc"; 1260 } 1261 #endif 1262 1263 /* 1264 * 0. Initial state 1265 * 1266 * Other FSM states can be visited zero or more times, but 1267 * this state is visited exactly once for each RPC. 1268 */ 1269 static void 1270 call_start(struct rpc_task *task) 1271 { 1272 struct rpc_clnt *clnt = task->tk_client; 1273 1274 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 1275 clnt->cl_protname, clnt->cl_vers, 1276 rpc_proc_name(task), 1277 (RPC_IS_ASYNC(task) ? "async" : "sync")); 1278 1279 /* Increment call count */ 1280 task->tk_msg.rpc_proc->p_count++; 1281 clnt->cl_stats->rpccnt++; 1282 task->tk_action = call_reserve; 1283 } 1284 1285 /* 1286 * 1. Reserve an RPC call slot 1287 */ 1288 static void 1289 call_reserve(struct rpc_task *task) 1290 { 1291 dprint_status(task); 1292 1293 task->tk_status = 0; 1294 task->tk_action = call_reserveresult; 1295 xprt_reserve(task); 1296 } 1297 1298 /* 1299 * 1b. Grok the result of xprt_reserve() 1300 */ 1301 static void 1302 call_reserveresult(struct rpc_task *task) 1303 { 1304 int status = task->tk_status; 1305 1306 dprint_status(task); 1307 1308 /* 1309 * After a call to xprt_reserve(), we must have either 1310 * a request slot or else an error status. 1311 */ 1312 task->tk_status = 0; 1313 if (status >= 0) { 1314 if (task->tk_rqstp) { 1315 task->tk_action = call_refresh; 1316 return; 1317 } 1318 1319 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1320 __func__, status); 1321 rpc_exit(task, -EIO); 1322 return; 1323 } 1324 1325 /* 1326 * Even though there was an error, we may have acquired 1327 * a request slot somehow. Make sure not to leak it. 1328 */ 1329 if (task->tk_rqstp) { 1330 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1331 __func__, status); 1332 xprt_release(task); 1333 } 1334 1335 switch (status) { 1336 case -ENOMEM: 1337 rpc_delay(task, HZ >> 2); 1338 case -EAGAIN: /* woken up; retry */ 1339 task->tk_action = call_reserve; 1340 return; 1341 case -EIO: /* probably a shutdown */ 1342 break; 1343 default: 1344 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1345 __func__, status); 1346 break; 1347 } 1348 rpc_exit(task, status); 1349 } 1350 1351 /* 1352 * 2. Bind and/or refresh the credentials 1353 */ 1354 static void 1355 call_refresh(struct rpc_task *task) 1356 { 1357 dprint_status(task); 1358 1359 task->tk_action = call_refreshresult; 1360 task->tk_status = 0; 1361 task->tk_client->cl_stats->rpcauthrefresh++; 1362 rpcauth_refreshcred(task); 1363 } 1364 1365 /* 1366 * 2a. Process the results of a credential refresh 1367 */ 1368 static void 1369 call_refreshresult(struct rpc_task *task) 1370 { 1371 int status = task->tk_status; 1372 1373 dprint_status(task); 1374 1375 task->tk_status = 0; 1376 task->tk_action = call_refresh; 1377 switch (status) { 1378 case 0: 1379 if (rpcauth_uptodatecred(task)) 1380 task->tk_action = call_allocate; 1381 return; 1382 case -ETIMEDOUT: 1383 rpc_delay(task, 3*HZ); 1384 case -EKEYEXPIRED: 1385 case -EAGAIN: 1386 status = -EACCES; 1387 if (!task->tk_cred_retry) 1388 break; 1389 task->tk_cred_retry--; 1390 dprintk("RPC: %5u %s: retry refresh creds\n", 1391 task->tk_pid, __func__); 1392 return; 1393 } 1394 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1395 task->tk_pid, __func__, status); 1396 rpc_exit(task, status); 1397 } 1398 1399 /* 1400 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1401 * (Note: buffer memory is freed in xprt_release). 1402 */ 1403 static void 1404 call_allocate(struct rpc_task *task) 1405 { 1406 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1407 struct rpc_rqst *req = task->tk_rqstp; 1408 struct rpc_xprt *xprt = task->tk_xprt; 1409 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1410 1411 dprint_status(task); 1412 1413 task->tk_status = 0; 1414 task->tk_action = call_bind; 1415 1416 if (req->rq_buffer) 1417 return; 1418 1419 if (proc->p_proc != 0) { 1420 BUG_ON(proc->p_arglen == 0); 1421 if (proc->p_decode != NULL) 1422 BUG_ON(proc->p_replen == 0); 1423 } 1424 1425 /* 1426 * Calculate the size (in quads) of the RPC call 1427 * and reply headers, and convert both values 1428 * to byte sizes. 1429 */ 1430 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1431 req->rq_callsize <<= 2; 1432 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1433 req->rq_rcvsize <<= 2; 1434 1435 req->rq_buffer = xprt->ops->buf_alloc(task, 1436 req->rq_callsize + req->rq_rcvsize); 1437 if (req->rq_buffer != NULL) 1438 return; 1439 1440 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1441 1442 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1443 task->tk_action = call_allocate; 1444 rpc_delay(task, HZ>>4); 1445 return; 1446 } 1447 1448 rpc_exit(task, -ERESTARTSYS); 1449 } 1450 1451 static inline int 1452 rpc_task_need_encode(struct rpc_task *task) 1453 { 1454 return task->tk_rqstp->rq_snd_buf.len == 0; 1455 } 1456 1457 static inline void 1458 rpc_task_force_reencode(struct rpc_task *task) 1459 { 1460 task->tk_rqstp->rq_snd_buf.len = 0; 1461 task->tk_rqstp->rq_bytes_sent = 0; 1462 } 1463 1464 static inline void 1465 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1466 { 1467 buf->head[0].iov_base = start; 1468 buf->head[0].iov_len = len; 1469 buf->tail[0].iov_len = 0; 1470 buf->page_len = 0; 1471 buf->flags = 0; 1472 buf->len = 0; 1473 buf->buflen = len; 1474 } 1475 1476 /* 1477 * 3. Encode arguments of an RPC call 1478 */ 1479 static void 1480 rpc_xdr_encode(struct rpc_task *task) 1481 { 1482 struct rpc_rqst *req = task->tk_rqstp; 1483 kxdreproc_t encode; 1484 __be32 *p; 1485 1486 dprint_status(task); 1487 1488 rpc_xdr_buf_init(&req->rq_snd_buf, 1489 req->rq_buffer, 1490 req->rq_callsize); 1491 rpc_xdr_buf_init(&req->rq_rcv_buf, 1492 (char *)req->rq_buffer + req->rq_callsize, 1493 req->rq_rcvsize); 1494 1495 p = rpc_encode_header(task); 1496 if (p == NULL) { 1497 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1498 rpc_exit(task, -EIO); 1499 return; 1500 } 1501 1502 encode = task->tk_msg.rpc_proc->p_encode; 1503 if (encode == NULL) 1504 return; 1505 1506 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1507 task->tk_msg.rpc_argp); 1508 } 1509 1510 /* 1511 * 4. Get the server port number if not yet set 1512 */ 1513 static void 1514 call_bind(struct rpc_task *task) 1515 { 1516 struct rpc_xprt *xprt = task->tk_xprt; 1517 1518 dprint_status(task); 1519 1520 task->tk_action = call_connect; 1521 if (!xprt_bound(xprt)) { 1522 task->tk_action = call_bind_status; 1523 task->tk_timeout = xprt->bind_timeout; 1524 xprt->ops->rpcbind(task); 1525 } 1526 } 1527 1528 /* 1529 * 4a. Sort out bind result 1530 */ 1531 static void 1532 call_bind_status(struct rpc_task *task) 1533 { 1534 int status = -EIO; 1535 1536 if (task->tk_status >= 0) { 1537 dprint_status(task); 1538 task->tk_status = 0; 1539 task->tk_action = call_connect; 1540 return; 1541 } 1542 1543 trace_rpc_bind_status(task); 1544 switch (task->tk_status) { 1545 case -ENOMEM: 1546 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1547 rpc_delay(task, HZ >> 2); 1548 goto retry_timeout; 1549 case -EACCES: 1550 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1551 "unavailable\n", task->tk_pid); 1552 /* fail immediately if this is an RPC ping */ 1553 if (task->tk_msg.rpc_proc->p_proc == 0) { 1554 status = -EOPNOTSUPP; 1555 break; 1556 } 1557 if (task->tk_rebind_retry == 0) 1558 break; 1559 task->tk_rebind_retry--; 1560 rpc_delay(task, 3*HZ); 1561 goto retry_timeout; 1562 case -ETIMEDOUT: 1563 dprintk("RPC: %5u rpcbind request timed out\n", 1564 task->tk_pid); 1565 goto retry_timeout; 1566 case -EPFNOSUPPORT: 1567 /* server doesn't support any rpcbind version we know of */ 1568 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1569 task->tk_pid); 1570 break; 1571 case -EPROTONOSUPPORT: 1572 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1573 task->tk_pid); 1574 task->tk_status = 0; 1575 task->tk_action = call_bind; 1576 return; 1577 case -ECONNREFUSED: /* connection problems */ 1578 case -ECONNRESET: 1579 case -ENOTCONN: 1580 case -EHOSTDOWN: 1581 case -EHOSTUNREACH: 1582 case -ENETUNREACH: 1583 case -EPIPE: 1584 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1585 task->tk_pid, task->tk_status); 1586 if (!RPC_IS_SOFTCONN(task)) { 1587 rpc_delay(task, 5*HZ); 1588 goto retry_timeout; 1589 } 1590 status = task->tk_status; 1591 break; 1592 default: 1593 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1594 task->tk_pid, -task->tk_status); 1595 } 1596 1597 rpc_exit(task, status); 1598 return; 1599 1600 retry_timeout: 1601 task->tk_action = call_timeout; 1602 } 1603 1604 /* 1605 * 4b. Connect to the RPC server 1606 */ 1607 static void 1608 call_connect(struct rpc_task *task) 1609 { 1610 struct rpc_xprt *xprt = task->tk_xprt; 1611 1612 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1613 task->tk_pid, xprt, 1614 (xprt_connected(xprt) ? "is" : "is not")); 1615 1616 task->tk_action = call_transmit; 1617 if (!xprt_connected(xprt)) { 1618 task->tk_action = call_connect_status; 1619 if (task->tk_status < 0) 1620 return; 1621 xprt_connect(task); 1622 } 1623 } 1624 1625 /* 1626 * 4c. Sort out connect result 1627 */ 1628 static void 1629 call_connect_status(struct rpc_task *task) 1630 { 1631 struct rpc_clnt *clnt = task->tk_client; 1632 int status = task->tk_status; 1633 1634 dprint_status(task); 1635 1636 task->tk_status = 0; 1637 if (status >= 0 || status == -EAGAIN) { 1638 clnt->cl_stats->netreconn++; 1639 task->tk_action = call_transmit; 1640 return; 1641 } 1642 1643 trace_rpc_connect_status(task, status); 1644 switch (status) { 1645 /* if soft mounted, test if we've timed out */ 1646 case -ETIMEDOUT: 1647 task->tk_action = call_timeout; 1648 break; 1649 default: 1650 rpc_exit(task, -EIO); 1651 } 1652 } 1653 1654 /* 1655 * 5. Transmit the RPC request, and wait for reply 1656 */ 1657 static void 1658 call_transmit(struct rpc_task *task) 1659 { 1660 dprint_status(task); 1661 1662 task->tk_action = call_status; 1663 if (task->tk_status < 0) 1664 return; 1665 task->tk_status = xprt_prepare_transmit(task); 1666 if (task->tk_status != 0) 1667 return; 1668 task->tk_action = call_transmit_status; 1669 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1670 if (rpc_task_need_encode(task)) { 1671 rpc_xdr_encode(task); 1672 /* Did the encode result in an error condition? */ 1673 if (task->tk_status != 0) { 1674 /* Was the error nonfatal? */ 1675 if (task->tk_status == -EAGAIN) 1676 rpc_delay(task, HZ >> 4); 1677 else 1678 rpc_exit(task, task->tk_status); 1679 return; 1680 } 1681 } 1682 xprt_transmit(task); 1683 if (task->tk_status < 0) 1684 return; 1685 /* 1686 * On success, ensure that we call xprt_end_transmit() before sleeping 1687 * in order to allow access to the socket to other RPC requests. 1688 */ 1689 call_transmit_status(task); 1690 if (rpc_reply_expected(task)) 1691 return; 1692 task->tk_action = rpc_exit_task; 1693 rpc_wake_up_queued_task(&task->tk_xprt->pending, task); 1694 } 1695 1696 /* 1697 * 5a. Handle cleanup after a transmission 1698 */ 1699 static void 1700 call_transmit_status(struct rpc_task *task) 1701 { 1702 task->tk_action = call_status; 1703 1704 /* 1705 * Common case: success. Force the compiler to put this 1706 * test first. 1707 */ 1708 if (task->tk_status == 0) { 1709 xprt_end_transmit(task); 1710 rpc_task_force_reencode(task); 1711 return; 1712 } 1713 1714 switch (task->tk_status) { 1715 case -EAGAIN: 1716 break; 1717 default: 1718 dprint_status(task); 1719 xprt_end_transmit(task); 1720 rpc_task_force_reencode(task); 1721 break; 1722 /* 1723 * Special cases: if we've been waiting on the 1724 * socket's write_space() callback, or if the 1725 * socket just returned a connection error, 1726 * then hold onto the transport lock. 1727 */ 1728 case -ECONNREFUSED: 1729 case -EHOSTDOWN: 1730 case -EHOSTUNREACH: 1731 case -ENETUNREACH: 1732 if (RPC_IS_SOFTCONN(task)) { 1733 xprt_end_transmit(task); 1734 rpc_exit(task, task->tk_status); 1735 break; 1736 } 1737 case -ECONNRESET: 1738 case -ENOTCONN: 1739 case -EPIPE: 1740 rpc_task_force_reencode(task); 1741 } 1742 } 1743 1744 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1745 /* 1746 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 1747 * addition, disconnect on connectivity errors. 1748 */ 1749 static void 1750 call_bc_transmit(struct rpc_task *task) 1751 { 1752 struct rpc_rqst *req = task->tk_rqstp; 1753 1754 task->tk_status = xprt_prepare_transmit(task); 1755 if (task->tk_status == -EAGAIN) { 1756 /* 1757 * Could not reserve the transport. Try again after the 1758 * transport is released. 1759 */ 1760 task->tk_status = 0; 1761 task->tk_action = call_bc_transmit; 1762 return; 1763 } 1764 1765 task->tk_action = rpc_exit_task; 1766 if (task->tk_status < 0) { 1767 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1768 "error: %d\n", task->tk_status); 1769 return; 1770 } 1771 1772 xprt_transmit(task); 1773 xprt_end_transmit(task); 1774 dprint_status(task); 1775 switch (task->tk_status) { 1776 case 0: 1777 /* Success */ 1778 break; 1779 case -EHOSTDOWN: 1780 case -EHOSTUNREACH: 1781 case -ENETUNREACH: 1782 case -ETIMEDOUT: 1783 /* 1784 * Problem reaching the server. Disconnect and let the 1785 * forechannel reestablish the connection. The server will 1786 * have to retransmit the backchannel request and we'll 1787 * reprocess it. Since these ops are idempotent, there's no 1788 * need to cache our reply at this time. 1789 */ 1790 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1791 "error: %d\n", task->tk_status); 1792 xprt_conditional_disconnect(task->tk_xprt, 1793 req->rq_connect_cookie); 1794 break; 1795 default: 1796 /* 1797 * We were unable to reply and will have to drop the 1798 * request. The server should reconnect and retransmit. 1799 */ 1800 WARN_ON_ONCE(task->tk_status == -EAGAIN); 1801 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1802 "error: %d\n", task->tk_status); 1803 break; 1804 } 1805 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 1806 } 1807 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1808 1809 /* 1810 * 6. Sort out the RPC call status 1811 */ 1812 static void 1813 call_status(struct rpc_task *task) 1814 { 1815 struct rpc_clnt *clnt = task->tk_client; 1816 struct rpc_rqst *req = task->tk_rqstp; 1817 int status; 1818 1819 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 1820 task->tk_status = req->rq_reply_bytes_recvd; 1821 1822 dprint_status(task); 1823 1824 status = task->tk_status; 1825 if (status >= 0) { 1826 task->tk_action = call_decode; 1827 return; 1828 } 1829 1830 trace_rpc_call_status(task); 1831 task->tk_status = 0; 1832 switch(status) { 1833 case -EHOSTDOWN: 1834 case -EHOSTUNREACH: 1835 case -ENETUNREACH: 1836 /* 1837 * Delay any retries for 3 seconds, then handle as if it 1838 * were a timeout. 1839 */ 1840 rpc_delay(task, 3*HZ); 1841 case -ETIMEDOUT: 1842 task->tk_action = call_timeout; 1843 if (task->tk_client->cl_discrtry) 1844 xprt_conditional_disconnect(task->tk_xprt, 1845 req->rq_connect_cookie); 1846 break; 1847 case -ECONNRESET: 1848 case -ECONNREFUSED: 1849 rpc_force_rebind(clnt); 1850 rpc_delay(task, 3*HZ); 1851 case -EPIPE: 1852 case -ENOTCONN: 1853 task->tk_action = call_bind; 1854 break; 1855 case -EAGAIN: 1856 task->tk_action = call_transmit; 1857 break; 1858 case -EIO: 1859 /* shutdown or soft timeout */ 1860 rpc_exit(task, status); 1861 break; 1862 default: 1863 if (clnt->cl_chatty) 1864 printk("%s: RPC call returned error %d\n", 1865 clnt->cl_protname, -status); 1866 rpc_exit(task, status); 1867 } 1868 } 1869 1870 /* 1871 * 6a. Handle RPC timeout 1872 * We do not release the request slot, so we keep using the 1873 * same XID for all retransmits. 1874 */ 1875 static void 1876 call_timeout(struct rpc_task *task) 1877 { 1878 struct rpc_clnt *clnt = task->tk_client; 1879 1880 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1881 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1882 goto retry; 1883 } 1884 1885 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1886 task->tk_timeouts++; 1887 1888 if (RPC_IS_SOFTCONN(task)) { 1889 rpc_exit(task, -ETIMEDOUT); 1890 return; 1891 } 1892 if (RPC_IS_SOFT(task)) { 1893 if (clnt->cl_chatty) { 1894 rcu_read_lock(); 1895 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1896 clnt->cl_protname, 1897 rcu_dereference(clnt->cl_xprt)->servername); 1898 rcu_read_unlock(); 1899 } 1900 if (task->tk_flags & RPC_TASK_TIMEOUT) 1901 rpc_exit(task, -ETIMEDOUT); 1902 else 1903 rpc_exit(task, -EIO); 1904 return; 1905 } 1906 1907 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1908 task->tk_flags |= RPC_CALL_MAJORSEEN; 1909 if (clnt->cl_chatty) { 1910 rcu_read_lock(); 1911 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1912 clnt->cl_protname, 1913 rcu_dereference(clnt->cl_xprt)->servername); 1914 rcu_read_unlock(); 1915 } 1916 } 1917 rpc_force_rebind(clnt); 1918 /* 1919 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1920 * event? RFC2203 requires the server to drop all such requests. 1921 */ 1922 rpcauth_invalcred(task); 1923 1924 retry: 1925 clnt->cl_stats->rpcretrans++; 1926 task->tk_action = call_bind; 1927 task->tk_status = 0; 1928 } 1929 1930 /* 1931 * 7. Decode the RPC reply 1932 */ 1933 static void 1934 call_decode(struct rpc_task *task) 1935 { 1936 struct rpc_clnt *clnt = task->tk_client; 1937 struct rpc_rqst *req = task->tk_rqstp; 1938 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 1939 __be32 *p; 1940 1941 dprint_status(task); 1942 1943 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1944 if (clnt->cl_chatty) { 1945 rcu_read_lock(); 1946 printk(KERN_NOTICE "%s: server %s OK\n", 1947 clnt->cl_protname, 1948 rcu_dereference(clnt->cl_xprt)->servername); 1949 rcu_read_unlock(); 1950 } 1951 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1952 } 1953 1954 /* 1955 * Ensure that we see all writes made by xprt_complete_rqst() 1956 * before it changed req->rq_reply_bytes_recvd. 1957 */ 1958 smp_rmb(); 1959 req->rq_rcv_buf.len = req->rq_private_buf.len; 1960 1961 /* Check that the softirq receive buffer is valid */ 1962 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1963 sizeof(req->rq_rcv_buf)) != 0); 1964 1965 if (req->rq_rcv_buf.len < 12) { 1966 if (!RPC_IS_SOFT(task)) { 1967 task->tk_action = call_bind; 1968 clnt->cl_stats->rpcretrans++; 1969 goto out_retry; 1970 } 1971 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1972 clnt->cl_protname, task->tk_status); 1973 task->tk_action = call_timeout; 1974 goto out_retry; 1975 } 1976 1977 p = rpc_verify_header(task); 1978 if (IS_ERR(p)) { 1979 if (p == ERR_PTR(-EAGAIN)) 1980 goto out_retry; 1981 return; 1982 } 1983 1984 task->tk_action = rpc_exit_task; 1985 1986 if (decode) { 1987 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1988 task->tk_msg.rpc_resp); 1989 } 1990 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1991 task->tk_status); 1992 return; 1993 out_retry: 1994 task->tk_status = 0; 1995 /* Note: rpc_verify_header() may have freed the RPC slot */ 1996 if (task->tk_rqstp == req) { 1997 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 1998 if (task->tk_client->cl_discrtry) 1999 xprt_conditional_disconnect(task->tk_xprt, 2000 req->rq_connect_cookie); 2001 } 2002 } 2003 2004 static __be32 * 2005 rpc_encode_header(struct rpc_task *task) 2006 { 2007 struct rpc_clnt *clnt = task->tk_client; 2008 struct rpc_rqst *req = task->tk_rqstp; 2009 __be32 *p = req->rq_svec[0].iov_base; 2010 2011 /* FIXME: check buffer size? */ 2012 2013 p = xprt_skip_transport_header(task->tk_xprt, p); 2014 *p++ = req->rq_xid; /* XID */ 2015 *p++ = htonl(RPC_CALL); /* CALL */ 2016 *p++ = htonl(RPC_VERSION); /* RPC version */ 2017 *p++ = htonl(clnt->cl_prog); /* program number */ 2018 *p++ = htonl(clnt->cl_vers); /* program version */ 2019 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 2020 p = rpcauth_marshcred(task, p); 2021 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 2022 return p; 2023 } 2024 2025 static __be32 * 2026 rpc_verify_header(struct rpc_task *task) 2027 { 2028 struct rpc_clnt *clnt = task->tk_client; 2029 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 2030 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 2031 __be32 *p = iov->iov_base; 2032 u32 n; 2033 int error = -EACCES; 2034 2035 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 2036 /* RFC-1014 says that the representation of XDR data must be a 2037 * multiple of four bytes 2038 * - if it isn't pointer subtraction in the NFS client may give 2039 * undefined results 2040 */ 2041 dprintk("RPC: %5u %s: XDR representation not a multiple of" 2042 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 2043 task->tk_rqstp->rq_rcv_buf.len); 2044 goto out_eio; 2045 } 2046 if ((len -= 3) < 0) 2047 goto out_overflow; 2048 2049 p += 1; /* skip XID */ 2050 if ((n = ntohl(*p++)) != RPC_REPLY) { 2051 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 2052 task->tk_pid, __func__, n); 2053 goto out_garbage; 2054 } 2055 2056 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 2057 if (--len < 0) 2058 goto out_overflow; 2059 switch ((n = ntohl(*p++))) { 2060 case RPC_AUTH_ERROR: 2061 break; 2062 case RPC_MISMATCH: 2063 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 2064 task->tk_pid, __func__); 2065 error = -EPROTONOSUPPORT; 2066 goto out_err; 2067 default: 2068 dprintk("RPC: %5u %s: RPC call rejected, " 2069 "unknown error: %x\n", 2070 task->tk_pid, __func__, n); 2071 goto out_eio; 2072 } 2073 if (--len < 0) 2074 goto out_overflow; 2075 switch ((n = ntohl(*p++))) { 2076 case RPC_AUTH_REJECTEDCRED: 2077 case RPC_AUTH_REJECTEDVERF: 2078 case RPCSEC_GSS_CREDPROBLEM: 2079 case RPCSEC_GSS_CTXPROBLEM: 2080 if (!task->tk_cred_retry) 2081 break; 2082 task->tk_cred_retry--; 2083 dprintk("RPC: %5u %s: retry stale creds\n", 2084 task->tk_pid, __func__); 2085 rpcauth_invalcred(task); 2086 /* Ensure we obtain a new XID! */ 2087 xprt_release(task); 2088 task->tk_action = call_reserve; 2089 goto out_retry; 2090 case RPC_AUTH_BADCRED: 2091 case RPC_AUTH_BADVERF: 2092 /* possibly garbled cred/verf? */ 2093 if (!task->tk_garb_retry) 2094 break; 2095 task->tk_garb_retry--; 2096 dprintk("RPC: %5u %s: retry garbled creds\n", 2097 task->tk_pid, __func__); 2098 task->tk_action = call_bind; 2099 goto out_retry; 2100 case RPC_AUTH_TOOWEAK: 2101 rcu_read_lock(); 2102 printk(KERN_NOTICE "RPC: server %s requires stronger " 2103 "authentication.\n", 2104 rcu_dereference(clnt->cl_xprt)->servername); 2105 rcu_read_unlock(); 2106 break; 2107 default: 2108 dprintk("RPC: %5u %s: unknown auth error: %x\n", 2109 task->tk_pid, __func__, n); 2110 error = -EIO; 2111 } 2112 dprintk("RPC: %5u %s: call rejected %d\n", 2113 task->tk_pid, __func__, n); 2114 goto out_err; 2115 } 2116 if (!(p = rpcauth_checkverf(task, p))) { 2117 dprintk("RPC: %5u %s: auth check failed\n", 2118 task->tk_pid, __func__); 2119 goto out_garbage; /* bad verifier, retry */ 2120 } 2121 len = p - (__be32 *)iov->iov_base - 1; 2122 if (len < 0) 2123 goto out_overflow; 2124 switch ((n = ntohl(*p++))) { 2125 case RPC_SUCCESS: 2126 return p; 2127 case RPC_PROG_UNAVAIL: 2128 dprintk_rcu("RPC: %5u %s: program %u is unsupported " 2129 "by server %s\n", task->tk_pid, __func__, 2130 (unsigned int)clnt->cl_prog, 2131 rcu_dereference(clnt->cl_xprt)->servername); 2132 error = -EPFNOSUPPORT; 2133 goto out_err; 2134 case RPC_PROG_MISMATCH: 2135 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported " 2136 "by server %s\n", task->tk_pid, __func__, 2137 (unsigned int)clnt->cl_prog, 2138 (unsigned int)clnt->cl_vers, 2139 rcu_dereference(clnt->cl_xprt)->servername); 2140 error = -EPROTONOSUPPORT; 2141 goto out_err; 2142 case RPC_PROC_UNAVAIL: 2143 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, " 2144 "version %u on server %s\n", 2145 task->tk_pid, __func__, 2146 rpc_proc_name(task), 2147 clnt->cl_prog, clnt->cl_vers, 2148 rcu_dereference(clnt->cl_xprt)->servername); 2149 error = -EOPNOTSUPP; 2150 goto out_err; 2151 case RPC_GARBAGE_ARGS: 2152 dprintk("RPC: %5u %s: server saw garbage\n", 2153 task->tk_pid, __func__); 2154 break; /* retry */ 2155 default: 2156 dprintk("RPC: %5u %s: server accept status: %x\n", 2157 task->tk_pid, __func__, n); 2158 /* Also retry */ 2159 } 2160 2161 out_garbage: 2162 clnt->cl_stats->rpcgarbage++; 2163 if (task->tk_garb_retry) { 2164 task->tk_garb_retry--; 2165 dprintk("RPC: %5u %s: retrying\n", 2166 task->tk_pid, __func__); 2167 task->tk_action = call_bind; 2168 out_retry: 2169 return ERR_PTR(-EAGAIN); 2170 } 2171 out_eio: 2172 error = -EIO; 2173 out_err: 2174 rpc_exit(task, error); 2175 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 2176 __func__, error); 2177 return ERR_PTR(error); 2178 out_overflow: 2179 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 2180 __func__); 2181 goto out_garbage; 2182 } 2183 2184 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2185 { 2186 } 2187 2188 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2189 { 2190 return 0; 2191 } 2192 2193 static struct rpc_procinfo rpcproc_null = { 2194 .p_encode = rpcproc_encode_null, 2195 .p_decode = rpcproc_decode_null, 2196 }; 2197 2198 static int rpc_ping(struct rpc_clnt *clnt) 2199 { 2200 struct rpc_message msg = { 2201 .rpc_proc = &rpcproc_null, 2202 }; 2203 int err; 2204 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2205 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 2206 put_rpccred(msg.rpc_cred); 2207 return err; 2208 } 2209 2210 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2211 { 2212 struct rpc_message msg = { 2213 .rpc_proc = &rpcproc_null, 2214 .rpc_cred = cred, 2215 }; 2216 struct rpc_task_setup task_setup_data = { 2217 .rpc_client = clnt, 2218 .rpc_message = &msg, 2219 .callback_ops = &rpc_default_ops, 2220 .flags = flags, 2221 }; 2222 return rpc_run_task(&task_setup_data); 2223 } 2224 EXPORT_SYMBOL_GPL(rpc_call_null); 2225 2226 #ifdef RPC_DEBUG 2227 static void rpc_show_header(void) 2228 { 2229 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 2230 "-timeout ---ops--\n"); 2231 } 2232 2233 static void rpc_show_task(const struct rpc_clnt *clnt, 2234 const struct rpc_task *task) 2235 { 2236 const char *rpc_waitq = "none"; 2237 2238 if (RPC_IS_QUEUED(task)) 2239 rpc_waitq = rpc_qname(task->tk_waitqueue); 2240 2241 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 2242 task->tk_pid, task->tk_flags, task->tk_status, 2243 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 2244 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task), 2245 task->tk_action, rpc_waitq); 2246 } 2247 2248 void rpc_show_tasks(struct net *net) 2249 { 2250 struct rpc_clnt *clnt; 2251 struct rpc_task *task; 2252 int header = 0; 2253 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 2254 2255 spin_lock(&sn->rpc_client_lock); 2256 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 2257 spin_lock(&clnt->cl_lock); 2258 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 2259 if (!header) { 2260 rpc_show_header(); 2261 header++; 2262 } 2263 rpc_show_task(clnt, task); 2264 } 2265 spin_unlock(&clnt->cl_lock); 2266 } 2267 spin_unlock(&sn->rpc_client_lock); 2268 } 2269 #endif 2270