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/addr.h> 37 #include <linux/sunrpc/rpc_pipe_fs.h> 38 #include <linux/sunrpc/metrics.h> 39 #include <linux/sunrpc/bc_xprt.h> 40 #include <trace/events/sunrpc.h> 41 42 #include "sunrpc.h" 43 #include "netns.h" 44 45 #ifdef RPC_DEBUG 46 # define RPCDBG_FACILITY RPCDBG_CALL 47 #endif 48 49 #define dprint_status(t) \ 50 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 51 __func__, t->tk_status) 52 53 /* 54 * All RPC clients are linked into this list 55 */ 56 57 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 58 59 60 static void call_start(struct rpc_task *task); 61 static void call_reserve(struct rpc_task *task); 62 static void call_reserveresult(struct rpc_task *task); 63 static void call_allocate(struct rpc_task *task); 64 static void call_decode(struct rpc_task *task); 65 static void call_bind(struct rpc_task *task); 66 static void call_bind_status(struct rpc_task *task); 67 static void call_transmit(struct rpc_task *task); 68 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 69 static void call_bc_transmit(struct rpc_task *task); 70 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 71 static void call_status(struct rpc_task *task); 72 static void call_transmit_status(struct rpc_task *task); 73 static void call_refresh(struct rpc_task *task); 74 static void call_refreshresult(struct rpc_task *task); 75 static void call_timeout(struct rpc_task *task); 76 static void call_connect(struct rpc_task *task); 77 static void call_connect_status(struct rpc_task *task); 78 79 static __be32 *rpc_encode_header(struct rpc_task *task); 80 static __be32 *rpc_verify_header(struct rpc_task *task); 81 static int rpc_ping(struct rpc_clnt *clnt); 82 83 static void rpc_register_client(struct rpc_clnt *clnt) 84 { 85 struct net *net = rpc_net_ns(clnt); 86 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 87 88 spin_lock(&sn->rpc_client_lock); 89 list_add(&clnt->cl_clients, &sn->all_clients); 90 spin_unlock(&sn->rpc_client_lock); 91 } 92 93 static void rpc_unregister_client(struct rpc_clnt *clnt) 94 { 95 struct net *net = rpc_net_ns(clnt); 96 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 97 98 spin_lock(&sn->rpc_client_lock); 99 list_del(&clnt->cl_clients); 100 spin_unlock(&sn->rpc_client_lock); 101 } 102 103 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 104 { 105 if (clnt->cl_dentry) { 106 if (clnt->cl_auth && clnt->cl_auth->au_ops->pipes_destroy) 107 clnt->cl_auth->au_ops->pipes_destroy(clnt->cl_auth); 108 rpc_remove_client_dir(clnt->cl_dentry); 109 } 110 clnt->cl_dentry = NULL; 111 } 112 113 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 114 { 115 struct net *net = rpc_net_ns(clnt); 116 struct super_block *pipefs_sb; 117 118 pipefs_sb = rpc_get_sb_net(net); 119 if (pipefs_sb) { 120 __rpc_clnt_remove_pipedir(clnt); 121 rpc_put_sb_net(net); 122 } 123 } 124 125 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 126 struct rpc_clnt *clnt, 127 const char *dir_name) 128 { 129 static uint32_t clntid; 130 char name[15]; 131 struct dentry *dir, *dentry; 132 133 dir = rpc_d_lookup_sb(sb, dir_name); 134 if (dir == NULL) { 135 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 136 return dir; 137 } 138 for (;;) { 139 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 140 name[sizeof(name) - 1] = '\0'; 141 dentry = rpc_create_client_dir(dir, name, clnt); 142 if (!IS_ERR(dentry)) 143 break; 144 if (dentry == ERR_PTR(-EEXIST)) 145 continue; 146 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 147 " %s/%s, error %ld\n", 148 dir_name, name, PTR_ERR(dentry)); 149 break; 150 } 151 dput(dir); 152 return dentry; 153 } 154 155 static int 156 rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name, 157 struct super_block *pipefs_sb) 158 { 159 struct dentry *dentry; 160 161 clnt->cl_dentry = NULL; 162 if (dir_name == NULL) 163 return 0; 164 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt, dir_name); 165 if (IS_ERR(dentry)) 166 return PTR_ERR(dentry); 167 clnt->cl_dentry = dentry; 168 return 0; 169 } 170 171 static inline int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 172 { 173 if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) || 174 ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry)) 175 return 1; 176 if ((event == RPC_PIPEFS_MOUNT) && atomic_read(&clnt->cl_count) == 0) 177 return 1; 178 return 0; 179 } 180 181 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 182 struct super_block *sb) 183 { 184 struct dentry *dentry; 185 int err = 0; 186 187 switch (event) { 188 case RPC_PIPEFS_MOUNT: 189 dentry = rpc_setup_pipedir_sb(sb, clnt, 190 clnt->cl_program->pipe_dir_name); 191 if (!dentry) 192 return -ENOENT; 193 if (IS_ERR(dentry)) 194 return PTR_ERR(dentry); 195 clnt->cl_dentry = dentry; 196 if (clnt->cl_auth->au_ops->pipes_create) { 197 err = clnt->cl_auth->au_ops->pipes_create(clnt->cl_auth); 198 if (err) 199 __rpc_clnt_remove_pipedir(clnt); 200 } 201 break; 202 case RPC_PIPEFS_UMOUNT: 203 __rpc_clnt_remove_pipedir(clnt); 204 break; 205 default: 206 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 207 return -ENOTSUPP; 208 } 209 return err; 210 } 211 212 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 213 struct super_block *sb) 214 { 215 int error = 0; 216 217 for (;; clnt = clnt->cl_parent) { 218 if (!rpc_clnt_skip_event(clnt, event)) 219 error = __rpc_clnt_handle_event(clnt, event, sb); 220 if (error || clnt == clnt->cl_parent) 221 break; 222 } 223 return error; 224 } 225 226 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 227 { 228 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 229 struct rpc_clnt *clnt; 230 231 spin_lock(&sn->rpc_client_lock); 232 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 233 if (clnt->cl_program->pipe_dir_name == NULL) 234 continue; 235 if (rpc_clnt_skip_event(clnt, event)) 236 continue; 237 spin_unlock(&sn->rpc_client_lock); 238 return clnt; 239 } 240 spin_unlock(&sn->rpc_client_lock); 241 return NULL; 242 } 243 244 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 245 void *ptr) 246 { 247 struct super_block *sb = ptr; 248 struct rpc_clnt *clnt; 249 int error = 0; 250 251 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 252 error = __rpc_pipefs_event(clnt, event, sb); 253 if (error) 254 break; 255 } 256 return error; 257 } 258 259 static struct notifier_block rpc_clients_block = { 260 .notifier_call = rpc_pipefs_event, 261 .priority = SUNRPC_PIPEFS_RPC_PRIO, 262 }; 263 264 int rpc_clients_notifier_register(void) 265 { 266 return rpc_pipefs_notifier_register(&rpc_clients_block); 267 } 268 269 void rpc_clients_notifier_unregister(void) 270 { 271 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 272 } 273 274 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 275 { 276 clnt->cl_nodelen = strlen(nodename); 277 if (clnt->cl_nodelen > UNX_MAXNODENAME) 278 clnt->cl_nodelen = UNX_MAXNODENAME; 279 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen); 280 } 281 282 static int rpc_client_register(const struct rpc_create_args *args, 283 struct rpc_clnt *clnt) 284 { 285 const struct rpc_program *program = args->program; 286 struct rpc_auth *auth; 287 struct net *net = rpc_net_ns(clnt); 288 struct super_block *pipefs_sb; 289 int err; 290 291 pipefs_sb = rpc_get_sb_net(net); 292 if (pipefs_sb) { 293 err = rpc_setup_pipedir(clnt, program->pipe_dir_name, pipefs_sb); 294 if (err) 295 goto out; 296 } 297 298 rpc_register_client(clnt); 299 if (pipefs_sb) 300 rpc_put_sb_net(net); 301 302 auth = rpcauth_create(args->authflavor, clnt); 303 if (IS_ERR(auth)) { 304 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 305 args->authflavor); 306 err = PTR_ERR(auth); 307 goto err_auth; 308 } 309 return 0; 310 err_auth: 311 pipefs_sb = rpc_get_sb_net(net); 312 __rpc_clnt_remove_pipedir(clnt); 313 out: 314 if (pipefs_sb) 315 rpc_put_sb_net(net); 316 return err; 317 } 318 319 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt) 320 { 321 const struct rpc_program *program = args->program; 322 const struct rpc_version *version; 323 struct rpc_clnt *clnt = NULL; 324 int err; 325 326 /* sanity check the name before trying to print it */ 327 dprintk("RPC: creating %s client for %s (xprt %p)\n", 328 program->name, args->servername, xprt); 329 330 err = rpciod_up(); 331 if (err) 332 goto out_no_rpciod; 333 334 err = -EINVAL; 335 if (args->version >= program->nrvers) 336 goto out_err; 337 version = program->version[args->version]; 338 if (version == NULL) 339 goto out_err; 340 341 err = -ENOMEM; 342 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 343 if (!clnt) 344 goto out_err; 345 clnt->cl_parent = clnt; 346 347 rcu_assign_pointer(clnt->cl_xprt, xprt); 348 clnt->cl_procinfo = version->procs; 349 clnt->cl_maxproc = version->nrprocs; 350 clnt->cl_protname = program->name; 351 clnt->cl_prog = args->prognumber ? : program->number; 352 clnt->cl_vers = version->number; 353 clnt->cl_stats = program->stats; 354 clnt->cl_metrics = rpc_alloc_iostats(clnt); 355 err = -ENOMEM; 356 if (clnt->cl_metrics == NULL) 357 goto out_no_stats; 358 clnt->cl_program = program; 359 INIT_LIST_HEAD(&clnt->cl_tasks); 360 spin_lock_init(&clnt->cl_lock); 361 362 if (!xprt_bound(xprt)) 363 clnt->cl_autobind = 1; 364 365 clnt->cl_timeout = xprt->timeout; 366 if (args->timeout != NULL) { 367 memcpy(&clnt->cl_timeout_default, args->timeout, 368 sizeof(clnt->cl_timeout_default)); 369 clnt->cl_timeout = &clnt->cl_timeout_default; 370 } 371 372 clnt->cl_rtt = &clnt->cl_rtt_default; 373 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 374 clnt->cl_principal = NULL; 375 if (args->client_name) { 376 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL); 377 if (!clnt->cl_principal) 378 goto out_no_principal; 379 } 380 381 atomic_set(&clnt->cl_count, 1); 382 383 /* save the nodename */ 384 rpc_clnt_set_nodename(clnt, utsname()->nodename); 385 386 err = rpc_client_register(args, clnt); 387 if (err) 388 goto out_no_path; 389 return clnt; 390 391 out_no_path: 392 kfree(clnt->cl_principal); 393 out_no_principal: 394 rpc_free_iostats(clnt->cl_metrics); 395 out_no_stats: 396 kfree(clnt); 397 out_err: 398 rpciod_down(); 399 out_no_rpciod: 400 xprt_put(xprt); 401 return ERR_PTR(err); 402 } 403 404 /** 405 * rpc_create - create an RPC client and transport with one call 406 * @args: rpc_clnt create argument structure 407 * 408 * Creates and initializes an RPC transport and an RPC client. 409 * 410 * It can ping the server in order to determine if it is up, and to see if 411 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 412 * this behavior so asynchronous tasks can also use rpc_create. 413 */ 414 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 415 { 416 struct rpc_xprt *xprt; 417 struct rpc_clnt *clnt; 418 struct xprt_create xprtargs = { 419 .net = args->net, 420 .ident = args->protocol, 421 .srcaddr = args->saddress, 422 .dstaddr = args->address, 423 .addrlen = args->addrsize, 424 .servername = args->servername, 425 .bc_xprt = args->bc_xprt, 426 }; 427 char servername[48]; 428 429 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 430 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 431 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 432 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 433 /* 434 * If the caller chooses not to specify a hostname, whip 435 * up a string representation of the passed-in address. 436 */ 437 if (xprtargs.servername == NULL) { 438 struct sockaddr_un *sun = 439 (struct sockaddr_un *)args->address; 440 struct sockaddr_in *sin = 441 (struct sockaddr_in *)args->address; 442 struct sockaddr_in6 *sin6 = 443 (struct sockaddr_in6 *)args->address; 444 445 servername[0] = '\0'; 446 switch (args->address->sa_family) { 447 case AF_LOCAL: 448 snprintf(servername, sizeof(servername), "%s", 449 sun->sun_path); 450 break; 451 case AF_INET: 452 snprintf(servername, sizeof(servername), "%pI4", 453 &sin->sin_addr.s_addr); 454 break; 455 case AF_INET6: 456 snprintf(servername, sizeof(servername), "%pI6", 457 &sin6->sin6_addr); 458 break; 459 default: 460 /* caller wants default server name, but 461 * address family isn't recognized. */ 462 return ERR_PTR(-EINVAL); 463 } 464 xprtargs.servername = servername; 465 } 466 467 xprt = xprt_create_transport(&xprtargs); 468 if (IS_ERR(xprt)) 469 return (struct rpc_clnt *)xprt; 470 471 /* 472 * By default, kernel RPC client connects from a reserved port. 473 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 474 * but it is always enabled for rpciod, which handles the connect 475 * operation. 476 */ 477 xprt->resvport = 1; 478 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 479 xprt->resvport = 0; 480 481 clnt = rpc_new_client(args, xprt); 482 if (IS_ERR(clnt)) 483 return clnt; 484 485 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 486 int err = rpc_ping(clnt); 487 if (err != 0) { 488 rpc_shutdown_client(clnt); 489 return ERR_PTR(err); 490 } 491 } 492 493 clnt->cl_softrtry = 1; 494 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 495 clnt->cl_softrtry = 0; 496 497 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 498 clnt->cl_autobind = 1; 499 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 500 clnt->cl_discrtry = 1; 501 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 502 clnt->cl_chatty = 1; 503 504 return clnt; 505 } 506 EXPORT_SYMBOL_GPL(rpc_create); 507 508 /* 509 * This function clones the RPC client structure. It allows us to share the 510 * same transport while varying parameters such as the authentication 511 * flavour. 512 */ 513 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 514 struct rpc_clnt *clnt) 515 { 516 struct rpc_xprt *xprt; 517 struct rpc_clnt *new; 518 int err; 519 520 err = -ENOMEM; 521 rcu_read_lock(); 522 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 523 rcu_read_unlock(); 524 if (xprt == NULL) 525 goto out_err; 526 args->servername = xprt->servername; 527 528 new = rpc_new_client(args, xprt); 529 if (IS_ERR(new)) { 530 err = PTR_ERR(new); 531 goto out_err; 532 } 533 534 atomic_inc(&clnt->cl_count); 535 new->cl_parent = clnt; 536 537 /* Turn off autobind on clones */ 538 new->cl_autobind = 0; 539 new->cl_softrtry = clnt->cl_softrtry; 540 new->cl_discrtry = clnt->cl_discrtry; 541 new->cl_chatty = clnt->cl_chatty; 542 return new; 543 544 out_err: 545 dprintk("RPC: %s: returned error %d\n", __func__, err); 546 return ERR_PTR(err); 547 } 548 549 /** 550 * rpc_clone_client - Clone an RPC client structure 551 * 552 * @clnt: RPC client whose parameters are copied 553 * 554 * Returns a fresh RPC client or an ERR_PTR. 555 */ 556 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 557 { 558 struct rpc_create_args args = { 559 .program = clnt->cl_program, 560 .prognumber = clnt->cl_prog, 561 .version = clnt->cl_vers, 562 .authflavor = clnt->cl_auth->au_flavor, 563 .client_name = clnt->cl_principal, 564 }; 565 return __rpc_clone_client(&args, clnt); 566 } 567 EXPORT_SYMBOL_GPL(rpc_clone_client); 568 569 /** 570 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 571 * 572 * @clnt: RPC client whose parameters are copied 573 * @flavor: security flavor for new client 574 * 575 * Returns a fresh RPC client or an ERR_PTR. 576 */ 577 struct rpc_clnt * 578 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 579 { 580 struct rpc_create_args args = { 581 .program = clnt->cl_program, 582 .prognumber = clnt->cl_prog, 583 .version = clnt->cl_vers, 584 .authflavor = flavor, 585 .client_name = clnt->cl_principal, 586 }; 587 return __rpc_clone_client(&args, clnt); 588 } 589 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 590 591 /* 592 * Kill all tasks for the given client. 593 * XXX: kill their descendants as well? 594 */ 595 void rpc_killall_tasks(struct rpc_clnt *clnt) 596 { 597 struct rpc_task *rovr; 598 599 600 if (list_empty(&clnt->cl_tasks)) 601 return; 602 dprintk("RPC: killing all tasks for client %p\n", clnt); 603 /* 604 * Spin lock all_tasks to prevent changes... 605 */ 606 spin_lock(&clnt->cl_lock); 607 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 608 if (!RPC_IS_ACTIVATED(rovr)) 609 continue; 610 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 611 rovr->tk_flags |= RPC_TASK_KILLED; 612 rpc_exit(rovr, -EIO); 613 if (RPC_IS_QUEUED(rovr)) 614 rpc_wake_up_queued_task(rovr->tk_waitqueue, 615 rovr); 616 } 617 } 618 spin_unlock(&clnt->cl_lock); 619 } 620 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 621 622 /* 623 * Properly shut down an RPC client, terminating all outstanding 624 * requests. 625 */ 626 void rpc_shutdown_client(struct rpc_clnt *clnt) 627 { 628 might_sleep(); 629 630 dprintk_rcu("RPC: shutting down %s client for %s\n", 631 clnt->cl_protname, 632 rcu_dereference(clnt->cl_xprt)->servername); 633 634 while (!list_empty(&clnt->cl_tasks)) { 635 rpc_killall_tasks(clnt); 636 wait_event_timeout(destroy_wait, 637 list_empty(&clnt->cl_tasks), 1*HZ); 638 } 639 640 rpc_release_client(clnt); 641 } 642 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 643 644 /* 645 * Free an RPC client 646 */ 647 static void 648 rpc_free_client(struct rpc_clnt *clnt) 649 { 650 dprintk_rcu("RPC: destroying %s client for %s\n", 651 clnt->cl_protname, 652 rcu_dereference(clnt->cl_xprt)->servername); 653 if (clnt->cl_parent != clnt) 654 rpc_release_client(clnt->cl_parent); 655 rpc_clnt_remove_pipedir(clnt); 656 rpc_unregister_client(clnt); 657 rpc_free_iostats(clnt->cl_metrics); 658 kfree(clnt->cl_principal); 659 clnt->cl_metrics = NULL; 660 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 661 rpciod_down(); 662 kfree(clnt); 663 } 664 665 /* 666 * Free an RPC client 667 */ 668 static void 669 rpc_free_auth(struct rpc_clnt *clnt) 670 { 671 if (clnt->cl_auth == NULL) { 672 rpc_free_client(clnt); 673 return; 674 } 675 676 /* 677 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 678 * release remaining GSS contexts. This mechanism ensures 679 * that it can do so safely. 680 */ 681 atomic_inc(&clnt->cl_count); 682 rpcauth_release(clnt->cl_auth); 683 clnt->cl_auth = NULL; 684 if (atomic_dec_and_test(&clnt->cl_count)) 685 rpc_free_client(clnt); 686 } 687 688 /* 689 * Release reference to the RPC client 690 */ 691 void 692 rpc_release_client(struct rpc_clnt *clnt) 693 { 694 dprintk("RPC: rpc_release_client(%p)\n", clnt); 695 696 if (list_empty(&clnt->cl_tasks)) 697 wake_up(&destroy_wait); 698 if (atomic_dec_and_test(&clnt->cl_count)) 699 rpc_free_auth(clnt); 700 } 701 EXPORT_SYMBOL_GPL(rpc_release_client); 702 703 /** 704 * rpc_bind_new_program - bind a new RPC program to an existing client 705 * @old: old rpc_client 706 * @program: rpc program to set 707 * @vers: rpc program version 708 * 709 * Clones the rpc client and sets up a new RPC program. This is mainly 710 * of use for enabling different RPC programs to share the same transport. 711 * The Sun NFSv2/v3 ACL protocol can do this. 712 */ 713 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 714 const struct rpc_program *program, 715 u32 vers) 716 { 717 struct rpc_create_args args = { 718 .program = program, 719 .prognumber = program->number, 720 .version = vers, 721 .authflavor = old->cl_auth->au_flavor, 722 .client_name = old->cl_principal, 723 }; 724 struct rpc_clnt *clnt; 725 int err; 726 727 clnt = __rpc_clone_client(&args, old); 728 if (IS_ERR(clnt)) 729 goto out; 730 err = rpc_ping(clnt); 731 if (err != 0) { 732 rpc_shutdown_client(clnt); 733 clnt = ERR_PTR(err); 734 } 735 out: 736 return clnt; 737 } 738 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 739 740 void rpc_task_release_client(struct rpc_task *task) 741 { 742 struct rpc_clnt *clnt = task->tk_client; 743 744 if (clnt != NULL) { 745 /* Remove from client task list */ 746 spin_lock(&clnt->cl_lock); 747 list_del(&task->tk_task); 748 spin_unlock(&clnt->cl_lock); 749 task->tk_client = NULL; 750 751 rpc_release_client(clnt); 752 } 753 } 754 755 static 756 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 757 { 758 if (clnt != NULL) { 759 rpc_task_release_client(task); 760 task->tk_client = clnt; 761 atomic_inc(&clnt->cl_count); 762 if (clnt->cl_softrtry) 763 task->tk_flags |= RPC_TASK_SOFT; 764 if (sk_memalloc_socks()) { 765 struct rpc_xprt *xprt; 766 767 rcu_read_lock(); 768 xprt = rcu_dereference(clnt->cl_xprt); 769 if (xprt->swapper) 770 task->tk_flags |= RPC_TASK_SWAPPER; 771 rcu_read_unlock(); 772 } 773 /* Add to the client's list of all tasks */ 774 spin_lock(&clnt->cl_lock); 775 list_add_tail(&task->tk_task, &clnt->cl_tasks); 776 spin_unlock(&clnt->cl_lock); 777 } 778 } 779 780 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) 781 { 782 rpc_task_release_client(task); 783 rpc_task_set_client(task, clnt); 784 } 785 EXPORT_SYMBOL_GPL(rpc_task_reset_client); 786 787 788 static void 789 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 790 { 791 if (msg != NULL) { 792 task->tk_msg.rpc_proc = msg->rpc_proc; 793 task->tk_msg.rpc_argp = msg->rpc_argp; 794 task->tk_msg.rpc_resp = msg->rpc_resp; 795 if (msg->rpc_cred != NULL) 796 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 797 } 798 } 799 800 /* 801 * Default callback for async RPC calls 802 */ 803 static void 804 rpc_default_callback(struct rpc_task *task, void *data) 805 { 806 } 807 808 static const struct rpc_call_ops rpc_default_ops = { 809 .rpc_call_done = rpc_default_callback, 810 }; 811 812 /** 813 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 814 * @task_setup_data: pointer to task initialisation data 815 */ 816 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 817 { 818 struct rpc_task *task; 819 820 task = rpc_new_task(task_setup_data); 821 if (IS_ERR(task)) 822 goto out; 823 824 rpc_task_set_client(task, task_setup_data->rpc_client); 825 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 826 827 if (task->tk_action == NULL) 828 rpc_call_start(task); 829 830 atomic_inc(&task->tk_count); 831 rpc_execute(task); 832 out: 833 return task; 834 } 835 EXPORT_SYMBOL_GPL(rpc_run_task); 836 837 /** 838 * rpc_call_sync - Perform a synchronous RPC call 839 * @clnt: pointer to RPC client 840 * @msg: RPC call parameters 841 * @flags: RPC call flags 842 */ 843 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 844 { 845 struct rpc_task *task; 846 struct rpc_task_setup task_setup_data = { 847 .rpc_client = clnt, 848 .rpc_message = msg, 849 .callback_ops = &rpc_default_ops, 850 .flags = flags, 851 }; 852 int status; 853 854 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 855 if (flags & RPC_TASK_ASYNC) { 856 rpc_release_calldata(task_setup_data.callback_ops, 857 task_setup_data.callback_data); 858 return -EINVAL; 859 } 860 861 task = rpc_run_task(&task_setup_data); 862 if (IS_ERR(task)) 863 return PTR_ERR(task); 864 status = task->tk_status; 865 rpc_put_task(task); 866 return status; 867 } 868 EXPORT_SYMBOL_GPL(rpc_call_sync); 869 870 /** 871 * rpc_call_async - Perform an asynchronous RPC call 872 * @clnt: pointer to RPC client 873 * @msg: RPC call parameters 874 * @flags: RPC call flags 875 * @tk_ops: RPC call ops 876 * @data: user call data 877 */ 878 int 879 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 880 const struct rpc_call_ops *tk_ops, void *data) 881 { 882 struct rpc_task *task; 883 struct rpc_task_setup task_setup_data = { 884 .rpc_client = clnt, 885 .rpc_message = msg, 886 .callback_ops = tk_ops, 887 .callback_data = data, 888 .flags = flags|RPC_TASK_ASYNC, 889 }; 890 891 task = rpc_run_task(&task_setup_data); 892 if (IS_ERR(task)) 893 return PTR_ERR(task); 894 rpc_put_task(task); 895 return 0; 896 } 897 EXPORT_SYMBOL_GPL(rpc_call_async); 898 899 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 900 /** 901 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 902 * rpc_execute against it 903 * @req: RPC request 904 * @tk_ops: RPC call ops 905 */ 906 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 907 const struct rpc_call_ops *tk_ops) 908 { 909 struct rpc_task *task; 910 struct xdr_buf *xbufp = &req->rq_snd_buf; 911 struct rpc_task_setup task_setup_data = { 912 .callback_ops = tk_ops, 913 }; 914 915 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 916 /* 917 * Create an rpc_task to send the data 918 */ 919 task = rpc_new_task(&task_setup_data); 920 if (IS_ERR(task)) { 921 xprt_free_bc_request(req); 922 goto out; 923 } 924 task->tk_rqstp = req; 925 926 /* 927 * Set up the xdr_buf length. 928 * This also indicates that the buffer is XDR encoded already. 929 */ 930 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 931 xbufp->tail[0].iov_len; 932 933 task->tk_action = call_bc_transmit; 934 atomic_inc(&task->tk_count); 935 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 936 rpc_execute(task); 937 938 out: 939 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 940 return task; 941 } 942 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 943 944 void 945 rpc_call_start(struct rpc_task *task) 946 { 947 task->tk_action = call_start; 948 } 949 EXPORT_SYMBOL_GPL(rpc_call_start); 950 951 /** 952 * rpc_peeraddr - extract remote peer address from clnt's xprt 953 * @clnt: RPC client structure 954 * @buf: target buffer 955 * @bufsize: length of target buffer 956 * 957 * Returns the number of bytes that are actually in the stored address. 958 */ 959 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 960 { 961 size_t bytes; 962 struct rpc_xprt *xprt; 963 964 rcu_read_lock(); 965 xprt = rcu_dereference(clnt->cl_xprt); 966 967 bytes = xprt->addrlen; 968 if (bytes > bufsize) 969 bytes = bufsize; 970 memcpy(buf, &xprt->addr, bytes); 971 rcu_read_unlock(); 972 973 return bytes; 974 } 975 EXPORT_SYMBOL_GPL(rpc_peeraddr); 976 977 /** 978 * rpc_peeraddr2str - return remote peer address in printable format 979 * @clnt: RPC client structure 980 * @format: address format 981 * 982 * NB: the lifetime of the memory referenced by the returned pointer is 983 * the same as the rpc_xprt itself. As long as the caller uses this 984 * pointer, it must hold the RCU read lock. 985 */ 986 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 987 enum rpc_display_format_t format) 988 { 989 struct rpc_xprt *xprt; 990 991 xprt = rcu_dereference(clnt->cl_xprt); 992 993 if (xprt->address_strings[format] != NULL) 994 return xprt->address_strings[format]; 995 else 996 return "unprintable"; 997 } 998 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 999 1000 static const struct sockaddr_in rpc_inaddr_loopback = { 1001 .sin_family = AF_INET, 1002 .sin_addr.s_addr = htonl(INADDR_ANY), 1003 }; 1004 1005 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1006 .sin6_family = AF_INET6, 1007 .sin6_addr = IN6ADDR_ANY_INIT, 1008 }; 1009 1010 /* 1011 * Try a getsockname() on a connected datagram socket. Using a 1012 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1013 * This conserves the ephemeral port number space. 1014 * 1015 * Returns zero and fills in "buf" if successful; otherwise, a 1016 * negative errno is returned. 1017 */ 1018 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1019 struct sockaddr *buf, int buflen) 1020 { 1021 struct socket *sock; 1022 int err; 1023 1024 err = __sock_create(net, sap->sa_family, 1025 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1026 if (err < 0) { 1027 dprintk("RPC: can't create UDP socket (%d)\n", err); 1028 goto out; 1029 } 1030 1031 switch (sap->sa_family) { 1032 case AF_INET: 1033 err = kernel_bind(sock, 1034 (struct sockaddr *)&rpc_inaddr_loopback, 1035 sizeof(rpc_inaddr_loopback)); 1036 break; 1037 case AF_INET6: 1038 err = kernel_bind(sock, 1039 (struct sockaddr *)&rpc_in6addr_loopback, 1040 sizeof(rpc_in6addr_loopback)); 1041 break; 1042 default: 1043 err = -EAFNOSUPPORT; 1044 goto out; 1045 } 1046 if (err < 0) { 1047 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1048 goto out_release; 1049 } 1050 1051 err = kernel_connect(sock, sap, salen, 0); 1052 if (err < 0) { 1053 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1054 goto out_release; 1055 } 1056 1057 err = kernel_getsockname(sock, buf, &buflen); 1058 if (err < 0) { 1059 dprintk("RPC: getsockname failed (%d)\n", err); 1060 goto out_release; 1061 } 1062 1063 err = 0; 1064 if (buf->sa_family == AF_INET6) { 1065 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1066 sin6->sin6_scope_id = 0; 1067 } 1068 dprintk("RPC: %s succeeded\n", __func__); 1069 1070 out_release: 1071 sock_release(sock); 1072 out: 1073 return err; 1074 } 1075 1076 /* 1077 * Scraping a connected socket failed, so we don't have a useable 1078 * local address. Fallback: generate an address that will prevent 1079 * the server from calling us back. 1080 * 1081 * Returns zero and fills in "buf" if successful; otherwise, a 1082 * negative errno is returned. 1083 */ 1084 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1085 { 1086 switch (family) { 1087 case AF_INET: 1088 if (buflen < sizeof(rpc_inaddr_loopback)) 1089 return -EINVAL; 1090 memcpy(buf, &rpc_inaddr_loopback, 1091 sizeof(rpc_inaddr_loopback)); 1092 break; 1093 case AF_INET6: 1094 if (buflen < sizeof(rpc_in6addr_loopback)) 1095 return -EINVAL; 1096 memcpy(buf, &rpc_in6addr_loopback, 1097 sizeof(rpc_in6addr_loopback)); 1098 default: 1099 dprintk("RPC: %s: address family not supported\n", 1100 __func__); 1101 return -EAFNOSUPPORT; 1102 } 1103 dprintk("RPC: %s: succeeded\n", __func__); 1104 return 0; 1105 } 1106 1107 /** 1108 * rpc_localaddr - discover local endpoint address for an RPC client 1109 * @clnt: RPC client structure 1110 * @buf: target buffer 1111 * @buflen: size of target buffer, in bytes 1112 * 1113 * Returns zero and fills in "buf" and "buflen" if successful; 1114 * otherwise, a negative errno is returned. 1115 * 1116 * This works even if the underlying transport is not currently connected, 1117 * or if the upper layer never previously provided a source address. 1118 * 1119 * The result of this function call is transient: multiple calls in 1120 * succession may give different results, depending on how local 1121 * networking configuration changes over time. 1122 */ 1123 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1124 { 1125 struct sockaddr_storage address; 1126 struct sockaddr *sap = (struct sockaddr *)&address; 1127 struct rpc_xprt *xprt; 1128 struct net *net; 1129 size_t salen; 1130 int err; 1131 1132 rcu_read_lock(); 1133 xprt = rcu_dereference(clnt->cl_xprt); 1134 salen = xprt->addrlen; 1135 memcpy(sap, &xprt->addr, salen); 1136 net = get_net(xprt->xprt_net); 1137 rcu_read_unlock(); 1138 1139 rpc_set_port(sap, 0); 1140 err = rpc_sockname(net, sap, salen, buf, buflen); 1141 put_net(net); 1142 if (err != 0) 1143 /* Couldn't discover local address, return ANYADDR */ 1144 return rpc_anyaddr(sap->sa_family, buf, buflen); 1145 return 0; 1146 } 1147 EXPORT_SYMBOL_GPL(rpc_localaddr); 1148 1149 void 1150 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1151 { 1152 struct rpc_xprt *xprt; 1153 1154 rcu_read_lock(); 1155 xprt = rcu_dereference(clnt->cl_xprt); 1156 if (xprt->ops->set_buffer_size) 1157 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1158 rcu_read_unlock(); 1159 } 1160 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1161 1162 /** 1163 * rpc_protocol - Get transport protocol number for an RPC client 1164 * @clnt: RPC client to query 1165 * 1166 */ 1167 int rpc_protocol(struct rpc_clnt *clnt) 1168 { 1169 int protocol; 1170 1171 rcu_read_lock(); 1172 protocol = rcu_dereference(clnt->cl_xprt)->prot; 1173 rcu_read_unlock(); 1174 return protocol; 1175 } 1176 EXPORT_SYMBOL_GPL(rpc_protocol); 1177 1178 /** 1179 * rpc_net_ns - Get the network namespace for this RPC client 1180 * @clnt: RPC client to query 1181 * 1182 */ 1183 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1184 { 1185 struct net *ret; 1186 1187 rcu_read_lock(); 1188 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1189 rcu_read_unlock(); 1190 return ret; 1191 } 1192 EXPORT_SYMBOL_GPL(rpc_net_ns); 1193 1194 /** 1195 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1196 * @clnt: RPC client to query 1197 * 1198 * For stream transports, this is one RPC record fragment (see RFC 1199 * 1831), as we don't support multi-record requests yet. For datagram 1200 * transports, this is the size of an IP packet minus the IP, UDP, and 1201 * RPC header sizes. 1202 */ 1203 size_t rpc_max_payload(struct rpc_clnt *clnt) 1204 { 1205 size_t ret; 1206 1207 rcu_read_lock(); 1208 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1209 rcu_read_unlock(); 1210 return ret; 1211 } 1212 EXPORT_SYMBOL_GPL(rpc_max_payload); 1213 1214 /** 1215 * rpc_get_timeout - Get timeout for transport in units of HZ 1216 * @clnt: RPC client to query 1217 */ 1218 unsigned long rpc_get_timeout(struct rpc_clnt *clnt) 1219 { 1220 unsigned long ret; 1221 1222 rcu_read_lock(); 1223 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval; 1224 rcu_read_unlock(); 1225 return ret; 1226 } 1227 EXPORT_SYMBOL_GPL(rpc_get_timeout); 1228 1229 /** 1230 * rpc_force_rebind - force transport to check that remote port is unchanged 1231 * @clnt: client to rebind 1232 * 1233 */ 1234 void rpc_force_rebind(struct rpc_clnt *clnt) 1235 { 1236 if (clnt->cl_autobind) { 1237 rcu_read_lock(); 1238 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1239 rcu_read_unlock(); 1240 } 1241 } 1242 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1243 1244 /* 1245 * Restart an (async) RPC call from the call_prepare state. 1246 * Usually called from within the exit handler. 1247 */ 1248 int 1249 rpc_restart_call_prepare(struct rpc_task *task) 1250 { 1251 if (RPC_ASSASSINATED(task)) 1252 return 0; 1253 task->tk_action = call_start; 1254 if (task->tk_ops->rpc_call_prepare != NULL) 1255 task->tk_action = rpc_prepare_task; 1256 return 1; 1257 } 1258 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1259 1260 /* 1261 * Restart an (async) RPC call. Usually called from within the 1262 * exit handler. 1263 */ 1264 int 1265 rpc_restart_call(struct rpc_task *task) 1266 { 1267 if (RPC_ASSASSINATED(task)) 1268 return 0; 1269 task->tk_action = call_start; 1270 return 1; 1271 } 1272 EXPORT_SYMBOL_GPL(rpc_restart_call); 1273 1274 #ifdef RPC_DEBUG 1275 static const char *rpc_proc_name(const struct rpc_task *task) 1276 { 1277 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1278 1279 if (proc) { 1280 if (proc->p_name) 1281 return proc->p_name; 1282 else 1283 return "NULL"; 1284 } else 1285 return "no proc"; 1286 } 1287 #endif 1288 1289 /* 1290 * 0. Initial state 1291 * 1292 * Other FSM states can be visited zero or more times, but 1293 * this state is visited exactly once for each RPC. 1294 */ 1295 static void 1296 call_start(struct rpc_task *task) 1297 { 1298 struct rpc_clnt *clnt = task->tk_client; 1299 1300 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 1301 clnt->cl_protname, clnt->cl_vers, 1302 rpc_proc_name(task), 1303 (RPC_IS_ASYNC(task) ? "async" : "sync")); 1304 1305 /* Increment call count */ 1306 task->tk_msg.rpc_proc->p_count++; 1307 clnt->cl_stats->rpccnt++; 1308 task->tk_action = call_reserve; 1309 } 1310 1311 /* 1312 * 1. Reserve an RPC call slot 1313 */ 1314 static void 1315 call_reserve(struct rpc_task *task) 1316 { 1317 dprint_status(task); 1318 1319 task->tk_status = 0; 1320 task->tk_action = call_reserveresult; 1321 xprt_reserve(task); 1322 } 1323 1324 static void call_retry_reserve(struct rpc_task *task); 1325 1326 /* 1327 * 1b. Grok the result of xprt_reserve() 1328 */ 1329 static void 1330 call_reserveresult(struct rpc_task *task) 1331 { 1332 int status = task->tk_status; 1333 1334 dprint_status(task); 1335 1336 /* 1337 * After a call to xprt_reserve(), we must have either 1338 * a request slot or else an error status. 1339 */ 1340 task->tk_status = 0; 1341 if (status >= 0) { 1342 if (task->tk_rqstp) { 1343 task->tk_action = call_refresh; 1344 return; 1345 } 1346 1347 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1348 __func__, status); 1349 rpc_exit(task, -EIO); 1350 return; 1351 } 1352 1353 /* 1354 * Even though there was an error, we may have acquired 1355 * a request slot somehow. Make sure not to leak it. 1356 */ 1357 if (task->tk_rqstp) { 1358 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1359 __func__, status); 1360 xprt_release(task); 1361 } 1362 1363 switch (status) { 1364 case -ENOMEM: 1365 rpc_delay(task, HZ >> 2); 1366 case -EAGAIN: /* woken up; retry */ 1367 task->tk_action = call_retry_reserve; 1368 return; 1369 case -EIO: /* probably a shutdown */ 1370 break; 1371 default: 1372 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1373 __func__, status); 1374 break; 1375 } 1376 rpc_exit(task, status); 1377 } 1378 1379 /* 1380 * 1c. Retry reserving an RPC call slot 1381 */ 1382 static void 1383 call_retry_reserve(struct rpc_task *task) 1384 { 1385 dprint_status(task); 1386 1387 task->tk_status = 0; 1388 task->tk_action = call_reserveresult; 1389 xprt_retry_reserve(task); 1390 } 1391 1392 /* 1393 * 2. Bind and/or refresh the credentials 1394 */ 1395 static void 1396 call_refresh(struct rpc_task *task) 1397 { 1398 dprint_status(task); 1399 1400 task->tk_action = call_refreshresult; 1401 task->tk_status = 0; 1402 task->tk_client->cl_stats->rpcauthrefresh++; 1403 rpcauth_refreshcred(task); 1404 } 1405 1406 /* 1407 * 2a. Process the results of a credential refresh 1408 */ 1409 static void 1410 call_refreshresult(struct rpc_task *task) 1411 { 1412 int status = task->tk_status; 1413 1414 dprint_status(task); 1415 1416 task->tk_status = 0; 1417 task->tk_action = call_refresh; 1418 switch (status) { 1419 case 0: 1420 if (rpcauth_uptodatecred(task)) 1421 task->tk_action = call_allocate; 1422 return; 1423 case -ETIMEDOUT: 1424 rpc_delay(task, 3*HZ); 1425 case -EKEYEXPIRED: 1426 case -EAGAIN: 1427 status = -EACCES; 1428 if (!task->tk_cred_retry) 1429 break; 1430 task->tk_cred_retry--; 1431 dprintk("RPC: %5u %s: retry refresh creds\n", 1432 task->tk_pid, __func__); 1433 return; 1434 } 1435 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1436 task->tk_pid, __func__, status); 1437 rpc_exit(task, status); 1438 } 1439 1440 /* 1441 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1442 * (Note: buffer memory is freed in xprt_release). 1443 */ 1444 static void 1445 call_allocate(struct rpc_task *task) 1446 { 1447 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1448 struct rpc_rqst *req = task->tk_rqstp; 1449 struct rpc_xprt *xprt = req->rq_xprt; 1450 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1451 1452 dprint_status(task); 1453 1454 task->tk_status = 0; 1455 task->tk_action = call_bind; 1456 1457 if (req->rq_buffer) 1458 return; 1459 1460 if (proc->p_proc != 0) { 1461 BUG_ON(proc->p_arglen == 0); 1462 if (proc->p_decode != NULL) 1463 BUG_ON(proc->p_replen == 0); 1464 } 1465 1466 /* 1467 * Calculate the size (in quads) of the RPC call 1468 * and reply headers, and convert both values 1469 * to byte sizes. 1470 */ 1471 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1472 req->rq_callsize <<= 2; 1473 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1474 req->rq_rcvsize <<= 2; 1475 1476 req->rq_buffer = xprt->ops->buf_alloc(task, 1477 req->rq_callsize + req->rq_rcvsize); 1478 if (req->rq_buffer != NULL) 1479 return; 1480 1481 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1482 1483 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1484 task->tk_action = call_allocate; 1485 rpc_delay(task, HZ>>4); 1486 return; 1487 } 1488 1489 rpc_exit(task, -ERESTARTSYS); 1490 } 1491 1492 static inline int 1493 rpc_task_need_encode(struct rpc_task *task) 1494 { 1495 return task->tk_rqstp->rq_snd_buf.len == 0; 1496 } 1497 1498 static inline void 1499 rpc_task_force_reencode(struct rpc_task *task) 1500 { 1501 task->tk_rqstp->rq_snd_buf.len = 0; 1502 task->tk_rqstp->rq_bytes_sent = 0; 1503 } 1504 1505 static inline void 1506 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1507 { 1508 buf->head[0].iov_base = start; 1509 buf->head[0].iov_len = len; 1510 buf->tail[0].iov_len = 0; 1511 buf->page_len = 0; 1512 buf->flags = 0; 1513 buf->len = 0; 1514 buf->buflen = len; 1515 } 1516 1517 /* 1518 * 3. Encode arguments of an RPC call 1519 */ 1520 static void 1521 rpc_xdr_encode(struct rpc_task *task) 1522 { 1523 struct rpc_rqst *req = task->tk_rqstp; 1524 kxdreproc_t encode; 1525 __be32 *p; 1526 1527 dprint_status(task); 1528 1529 rpc_xdr_buf_init(&req->rq_snd_buf, 1530 req->rq_buffer, 1531 req->rq_callsize); 1532 rpc_xdr_buf_init(&req->rq_rcv_buf, 1533 (char *)req->rq_buffer + req->rq_callsize, 1534 req->rq_rcvsize); 1535 1536 p = rpc_encode_header(task); 1537 if (p == NULL) { 1538 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1539 rpc_exit(task, -EIO); 1540 return; 1541 } 1542 1543 encode = task->tk_msg.rpc_proc->p_encode; 1544 if (encode == NULL) 1545 return; 1546 1547 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1548 task->tk_msg.rpc_argp); 1549 } 1550 1551 /* 1552 * 4. Get the server port number if not yet set 1553 */ 1554 static void 1555 call_bind(struct rpc_task *task) 1556 { 1557 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1558 1559 dprint_status(task); 1560 1561 task->tk_action = call_connect; 1562 if (!xprt_bound(xprt)) { 1563 task->tk_action = call_bind_status; 1564 task->tk_timeout = xprt->bind_timeout; 1565 xprt->ops->rpcbind(task); 1566 } 1567 } 1568 1569 /* 1570 * 4a. Sort out bind result 1571 */ 1572 static void 1573 call_bind_status(struct rpc_task *task) 1574 { 1575 int status = -EIO; 1576 1577 if (task->tk_status >= 0) { 1578 dprint_status(task); 1579 task->tk_status = 0; 1580 task->tk_action = call_connect; 1581 return; 1582 } 1583 1584 trace_rpc_bind_status(task); 1585 switch (task->tk_status) { 1586 case -ENOMEM: 1587 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1588 rpc_delay(task, HZ >> 2); 1589 goto retry_timeout; 1590 case -EACCES: 1591 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1592 "unavailable\n", task->tk_pid); 1593 /* fail immediately if this is an RPC ping */ 1594 if (task->tk_msg.rpc_proc->p_proc == 0) { 1595 status = -EOPNOTSUPP; 1596 break; 1597 } 1598 if (task->tk_rebind_retry == 0) 1599 break; 1600 task->tk_rebind_retry--; 1601 rpc_delay(task, 3*HZ); 1602 goto retry_timeout; 1603 case -ETIMEDOUT: 1604 dprintk("RPC: %5u rpcbind request timed out\n", 1605 task->tk_pid); 1606 goto retry_timeout; 1607 case -EPFNOSUPPORT: 1608 /* server doesn't support any rpcbind version we know of */ 1609 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1610 task->tk_pid); 1611 break; 1612 case -EPROTONOSUPPORT: 1613 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1614 task->tk_pid); 1615 task->tk_status = 0; 1616 task->tk_action = call_bind; 1617 return; 1618 case -ECONNREFUSED: /* connection problems */ 1619 case -ECONNRESET: 1620 case -ENOTCONN: 1621 case -EHOSTDOWN: 1622 case -EHOSTUNREACH: 1623 case -ENETUNREACH: 1624 case -EPIPE: 1625 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1626 task->tk_pid, task->tk_status); 1627 if (!RPC_IS_SOFTCONN(task)) { 1628 rpc_delay(task, 5*HZ); 1629 goto retry_timeout; 1630 } 1631 status = task->tk_status; 1632 break; 1633 default: 1634 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1635 task->tk_pid, -task->tk_status); 1636 } 1637 1638 rpc_exit(task, status); 1639 return; 1640 1641 retry_timeout: 1642 task->tk_action = call_timeout; 1643 } 1644 1645 /* 1646 * 4b. Connect to the RPC server 1647 */ 1648 static void 1649 call_connect(struct rpc_task *task) 1650 { 1651 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1652 1653 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1654 task->tk_pid, xprt, 1655 (xprt_connected(xprt) ? "is" : "is not")); 1656 1657 task->tk_action = call_transmit; 1658 if (!xprt_connected(xprt)) { 1659 task->tk_action = call_connect_status; 1660 if (task->tk_status < 0) 1661 return; 1662 xprt_connect(task); 1663 } 1664 } 1665 1666 /* 1667 * 4c. Sort out connect result 1668 */ 1669 static void 1670 call_connect_status(struct rpc_task *task) 1671 { 1672 struct rpc_clnt *clnt = task->tk_client; 1673 int status = task->tk_status; 1674 1675 dprint_status(task); 1676 1677 trace_rpc_connect_status(task, status); 1678 switch (status) { 1679 /* if soft mounted, test if we've timed out */ 1680 case -ETIMEDOUT: 1681 task->tk_action = call_timeout; 1682 return; 1683 case -ECONNREFUSED: 1684 case -ECONNRESET: 1685 case -ENETUNREACH: 1686 if (RPC_IS_SOFTCONN(task)) 1687 break; 1688 /* retry with existing socket, after a delay */ 1689 case 0: 1690 case -EAGAIN: 1691 task->tk_status = 0; 1692 clnt->cl_stats->netreconn++; 1693 task->tk_action = call_transmit; 1694 return; 1695 } 1696 rpc_exit(task, status); 1697 } 1698 1699 /* 1700 * 5. Transmit the RPC request, and wait for reply 1701 */ 1702 static void 1703 call_transmit(struct rpc_task *task) 1704 { 1705 dprint_status(task); 1706 1707 task->tk_action = call_status; 1708 if (task->tk_status < 0) 1709 return; 1710 task->tk_status = xprt_prepare_transmit(task); 1711 if (task->tk_status != 0) 1712 return; 1713 task->tk_action = call_transmit_status; 1714 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1715 if (rpc_task_need_encode(task)) { 1716 rpc_xdr_encode(task); 1717 /* Did the encode result in an error condition? */ 1718 if (task->tk_status != 0) { 1719 /* Was the error nonfatal? */ 1720 if (task->tk_status == -EAGAIN) 1721 rpc_delay(task, HZ >> 4); 1722 else 1723 rpc_exit(task, task->tk_status); 1724 return; 1725 } 1726 } 1727 xprt_transmit(task); 1728 if (task->tk_status < 0) 1729 return; 1730 /* 1731 * On success, ensure that we call xprt_end_transmit() before sleeping 1732 * in order to allow access to the socket to other RPC requests. 1733 */ 1734 call_transmit_status(task); 1735 if (rpc_reply_expected(task)) 1736 return; 1737 task->tk_action = rpc_exit_task; 1738 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task); 1739 } 1740 1741 /* 1742 * 5a. Handle cleanup after a transmission 1743 */ 1744 static void 1745 call_transmit_status(struct rpc_task *task) 1746 { 1747 task->tk_action = call_status; 1748 1749 /* 1750 * Common case: success. Force the compiler to put this 1751 * test first. 1752 */ 1753 if (task->tk_status == 0) { 1754 xprt_end_transmit(task); 1755 rpc_task_force_reencode(task); 1756 return; 1757 } 1758 1759 switch (task->tk_status) { 1760 case -EAGAIN: 1761 break; 1762 default: 1763 dprint_status(task); 1764 xprt_end_transmit(task); 1765 rpc_task_force_reencode(task); 1766 break; 1767 /* 1768 * Special cases: if we've been waiting on the 1769 * socket's write_space() callback, or if the 1770 * socket just returned a connection error, 1771 * then hold onto the transport lock. 1772 */ 1773 case -ECONNREFUSED: 1774 case -EHOSTDOWN: 1775 case -EHOSTUNREACH: 1776 case -ENETUNREACH: 1777 if (RPC_IS_SOFTCONN(task)) { 1778 xprt_end_transmit(task); 1779 rpc_exit(task, task->tk_status); 1780 break; 1781 } 1782 case -ECONNRESET: 1783 case -ENOTCONN: 1784 case -EPIPE: 1785 rpc_task_force_reencode(task); 1786 } 1787 } 1788 1789 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1790 /* 1791 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 1792 * addition, disconnect on connectivity errors. 1793 */ 1794 static void 1795 call_bc_transmit(struct rpc_task *task) 1796 { 1797 struct rpc_rqst *req = task->tk_rqstp; 1798 1799 task->tk_status = xprt_prepare_transmit(task); 1800 if (task->tk_status == -EAGAIN) { 1801 /* 1802 * Could not reserve the transport. Try again after the 1803 * transport is released. 1804 */ 1805 task->tk_status = 0; 1806 task->tk_action = call_bc_transmit; 1807 return; 1808 } 1809 1810 task->tk_action = rpc_exit_task; 1811 if (task->tk_status < 0) { 1812 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1813 "error: %d\n", task->tk_status); 1814 return; 1815 } 1816 1817 xprt_transmit(task); 1818 xprt_end_transmit(task); 1819 dprint_status(task); 1820 switch (task->tk_status) { 1821 case 0: 1822 /* Success */ 1823 break; 1824 case -EHOSTDOWN: 1825 case -EHOSTUNREACH: 1826 case -ENETUNREACH: 1827 case -ETIMEDOUT: 1828 /* 1829 * Problem reaching the server. Disconnect and let the 1830 * forechannel reestablish the connection. The server will 1831 * have to retransmit the backchannel request and we'll 1832 * reprocess it. Since these ops are idempotent, there's no 1833 * need to cache our reply at this time. 1834 */ 1835 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1836 "error: %d\n", task->tk_status); 1837 xprt_conditional_disconnect(req->rq_xprt, 1838 req->rq_connect_cookie); 1839 break; 1840 default: 1841 /* 1842 * We were unable to reply and will have to drop the 1843 * request. The server should reconnect and retransmit. 1844 */ 1845 WARN_ON_ONCE(task->tk_status == -EAGAIN); 1846 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1847 "error: %d\n", task->tk_status); 1848 break; 1849 } 1850 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 1851 } 1852 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1853 1854 /* 1855 * 6. Sort out the RPC call status 1856 */ 1857 static void 1858 call_status(struct rpc_task *task) 1859 { 1860 struct rpc_clnt *clnt = task->tk_client; 1861 struct rpc_rqst *req = task->tk_rqstp; 1862 int status; 1863 1864 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 1865 task->tk_status = req->rq_reply_bytes_recvd; 1866 1867 dprint_status(task); 1868 1869 status = task->tk_status; 1870 if (status >= 0) { 1871 task->tk_action = call_decode; 1872 return; 1873 } 1874 1875 trace_rpc_call_status(task); 1876 task->tk_status = 0; 1877 switch(status) { 1878 case -EHOSTDOWN: 1879 case -EHOSTUNREACH: 1880 case -ENETUNREACH: 1881 /* 1882 * Delay any retries for 3 seconds, then handle as if it 1883 * were a timeout. 1884 */ 1885 rpc_delay(task, 3*HZ); 1886 case -ETIMEDOUT: 1887 task->tk_action = call_timeout; 1888 if (task->tk_client->cl_discrtry) 1889 xprt_conditional_disconnect(req->rq_xprt, 1890 req->rq_connect_cookie); 1891 break; 1892 case -ECONNRESET: 1893 case -ECONNREFUSED: 1894 rpc_force_rebind(clnt); 1895 rpc_delay(task, 3*HZ); 1896 case -EPIPE: 1897 case -ENOTCONN: 1898 task->tk_action = call_bind; 1899 break; 1900 case -EAGAIN: 1901 task->tk_action = call_transmit; 1902 break; 1903 case -EIO: 1904 /* shutdown or soft timeout */ 1905 rpc_exit(task, status); 1906 break; 1907 default: 1908 if (clnt->cl_chatty) 1909 printk("%s: RPC call returned error %d\n", 1910 clnt->cl_protname, -status); 1911 rpc_exit(task, status); 1912 } 1913 } 1914 1915 /* 1916 * 6a. Handle RPC timeout 1917 * We do not release the request slot, so we keep using the 1918 * same XID for all retransmits. 1919 */ 1920 static void 1921 call_timeout(struct rpc_task *task) 1922 { 1923 struct rpc_clnt *clnt = task->tk_client; 1924 1925 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1926 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1927 goto retry; 1928 } 1929 1930 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1931 task->tk_timeouts++; 1932 1933 if (RPC_IS_SOFTCONN(task)) { 1934 rpc_exit(task, -ETIMEDOUT); 1935 return; 1936 } 1937 if (RPC_IS_SOFT(task)) { 1938 if (clnt->cl_chatty) { 1939 rcu_read_lock(); 1940 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1941 clnt->cl_protname, 1942 rcu_dereference(clnt->cl_xprt)->servername); 1943 rcu_read_unlock(); 1944 } 1945 if (task->tk_flags & RPC_TASK_TIMEOUT) 1946 rpc_exit(task, -ETIMEDOUT); 1947 else 1948 rpc_exit(task, -EIO); 1949 return; 1950 } 1951 1952 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1953 task->tk_flags |= RPC_CALL_MAJORSEEN; 1954 if (clnt->cl_chatty) { 1955 rcu_read_lock(); 1956 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1957 clnt->cl_protname, 1958 rcu_dereference(clnt->cl_xprt)->servername); 1959 rcu_read_unlock(); 1960 } 1961 } 1962 rpc_force_rebind(clnt); 1963 /* 1964 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1965 * event? RFC2203 requires the server to drop all such requests. 1966 */ 1967 rpcauth_invalcred(task); 1968 1969 retry: 1970 clnt->cl_stats->rpcretrans++; 1971 task->tk_action = call_bind; 1972 task->tk_status = 0; 1973 } 1974 1975 /* 1976 * 7. Decode the RPC reply 1977 */ 1978 static void 1979 call_decode(struct rpc_task *task) 1980 { 1981 struct rpc_clnt *clnt = task->tk_client; 1982 struct rpc_rqst *req = task->tk_rqstp; 1983 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 1984 __be32 *p; 1985 1986 dprint_status(task); 1987 1988 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1989 if (clnt->cl_chatty) { 1990 rcu_read_lock(); 1991 printk(KERN_NOTICE "%s: server %s OK\n", 1992 clnt->cl_protname, 1993 rcu_dereference(clnt->cl_xprt)->servername); 1994 rcu_read_unlock(); 1995 } 1996 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1997 } 1998 1999 /* 2000 * Ensure that we see all writes made by xprt_complete_rqst() 2001 * before it changed req->rq_reply_bytes_recvd. 2002 */ 2003 smp_rmb(); 2004 req->rq_rcv_buf.len = req->rq_private_buf.len; 2005 2006 /* Check that the softirq receive buffer is valid */ 2007 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2008 sizeof(req->rq_rcv_buf)) != 0); 2009 2010 if (req->rq_rcv_buf.len < 12) { 2011 if (!RPC_IS_SOFT(task)) { 2012 task->tk_action = call_bind; 2013 clnt->cl_stats->rpcretrans++; 2014 goto out_retry; 2015 } 2016 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 2017 clnt->cl_protname, task->tk_status); 2018 task->tk_action = call_timeout; 2019 goto out_retry; 2020 } 2021 2022 p = rpc_verify_header(task); 2023 if (IS_ERR(p)) { 2024 if (p == ERR_PTR(-EAGAIN)) 2025 goto out_retry; 2026 return; 2027 } 2028 2029 task->tk_action = rpc_exit_task; 2030 2031 if (decode) { 2032 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 2033 task->tk_msg.rpc_resp); 2034 } 2035 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 2036 task->tk_status); 2037 return; 2038 out_retry: 2039 task->tk_status = 0; 2040 /* Note: rpc_verify_header() may have freed the RPC slot */ 2041 if (task->tk_rqstp == req) { 2042 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 2043 if (task->tk_client->cl_discrtry) 2044 xprt_conditional_disconnect(req->rq_xprt, 2045 req->rq_connect_cookie); 2046 } 2047 } 2048 2049 static __be32 * 2050 rpc_encode_header(struct rpc_task *task) 2051 { 2052 struct rpc_clnt *clnt = task->tk_client; 2053 struct rpc_rqst *req = task->tk_rqstp; 2054 __be32 *p = req->rq_svec[0].iov_base; 2055 2056 /* FIXME: check buffer size? */ 2057 2058 p = xprt_skip_transport_header(req->rq_xprt, p); 2059 *p++ = req->rq_xid; /* XID */ 2060 *p++ = htonl(RPC_CALL); /* CALL */ 2061 *p++ = htonl(RPC_VERSION); /* RPC version */ 2062 *p++ = htonl(clnt->cl_prog); /* program number */ 2063 *p++ = htonl(clnt->cl_vers); /* program version */ 2064 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 2065 p = rpcauth_marshcred(task, p); 2066 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 2067 return p; 2068 } 2069 2070 static __be32 * 2071 rpc_verify_header(struct rpc_task *task) 2072 { 2073 struct rpc_clnt *clnt = task->tk_client; 2074 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 2075 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 2076 __be32 *p = iov->iov_base; 2077 u32 n; 2078 int error = -EACCES; 2079 2080 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 2081 /* RFC-1014 says that the representation of XDR data must be a 2082 * multiple of four bytes 2083 * - if it isn't pointer subtraction in the NFS client may give 2084 * undefined results 2085 */ 2086 dprintk("RPC: %5u %s: XDR representation not a multiple of" 2087 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 2088 task->tk_rqstp->rq_rcv_buf.len); 2089 goto out_eio; 2090 } 2091 if ((len -= 3) < 0) 2092 goto out_overflow; 2093 2094 p += 1; /* skip XID */ 2095 if ((n = ntohl(*p++)) != RPC_REPLY) { 2096 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 2097 task->tk_pid, __func__, n); 2098 goto out_garbage; 2099 } 2100 2101 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 2102 if (--len < 0) 2103 goto out_overflow; 2104 switch ((n = ntohl(*p++))) { 2105 case RPC_AUTH_ERROR: 2106 break; 2107 case RPC_MISMATCH: 2108 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 2109 task->tk_pid, __func__); 2110 error = -EPROTONOSUPPORT; 2111 goto out_err; 2112 default: 2113 dprintk("RPC: %5u %s: RPC call rejected, " 2114 "unknown error: %x\n", 2115 task->tk_pid, __func__, n); 2116 goto out_eio; 2117 } 2118 if (--len < 0) 2119 goto out_overflow; 2120 switch ((n = ntohl(*p++))) { 2121 case RPC_AUTH_REJECTEDCRED: 2122 case RPC_AUTH_REJECTEDVERF: 2123 case RPCSEC_GSS_CREDPROBLEM: 2124 case RPCSEC_GSS_CTXPROBLEM: 2125 if (!task->tk_cred_retry) 2126 break; 2127 task->tk_cred_retry--; 2128 dprintk("RPC: %5u %s: retry stale creds\n", 2129 task->tk_pid, __func__); 2130 rpcauth_invalcred(task); 2131 /* Ensure we obtain a new XID! */ 2132 xprt_release(task); 2133 task->tk_action = call_reserve; 2134 goto out_retry; 2135 case RPC_AUTH_BADCRED: 2136 case RPC_AUTH_BADVERF: 2137 /* possibly garbled cred/verf? */ 2138 if (!task->tk_garb_retry) 2139 break; 2140 task->tk_garb_retry--; 2141 dprintk("RPC: %5u %s: retry garbled creds\n", 2142 task->tk_pid, __func__); 2143 task->tk_action = call_bind; 2144 goto out_retry; 2145 case RPC_AUTH_TOOWEAK: 2146 rcu_read_lock(); 2147 printk(KERN_NOTICE "RPC: server %s requires stronger " 2148 "authentication.\n", 2149 rcu_dereference(clnt->cl_xprt)->servername); 2150 rcu_read_unlock(); 2151 break; 2152 default: 2153 dprintk("RPC: %5u %s: unknown auth error: %x\n", 2154 task->tk_pid, __func__, n); 2155 error = -EIO; 2156 } 2157 dprintk("RPC: %5u %s: call rejected %d\n", 2158 task->tk_pid, __func__, n); 2159 goto out_err; 2160 } 2161 if (!(p = rpcauth_checkverf(task, p))) { 2162 dprintk("RPC: %5u %s: auth check failed\n", 2163 task->tk_pid, __func__); 2164 goto out_garbage; /* bad verifier, retry */ 2165 } 2166 len = p - (__be32 *)iov->iov_base - 1; 2167 if (len < 0) 2168 goto out_overflow; 2169 switch ((n = ntohl(*p++))) { 2170 case RPC_SUCCESS: 2171 return p; 2172 case RPC_PROG_UNAVAIL: 2173 dprintk_rcu("RPC: %5u %s: program %u is unsupported " 2174 "by server %s\n", task->tk_pid, __func__, 2175 (unsigned int)clnt->cl_prog, 2176 rcu_dereference(clnt->cl_xprt)->servername); 2177 error = -EPFNOSUPPORT; 2178 goto out_err; 2179 case RPC_PROG_MISMATCH: 2180 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported " 2181 "by server %s\n", task->tk_pid, __func__, 2182 (unsigned int)clnt->cl_prog, 2183 (unsigned int)clnt->cl_vers, 2184 rcu_dereference(clnt->cl_xprt)->servername); 2185 error = -EPROTONOSUPPORT; 2186 goto out_err; 2187 case RPC_PROC_UNAVAIL: 2188 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, " 2189 "version %u on server %s\n", 2190 task->tk_pid, __func__, 2191 rpc_proc_name(task), 2192 clnt->cl_prog, clnt->cl_vers, 2193 rcu_dereference(clnt->cl_xprt)->servername); 2194 error = -EOPNOTSUPP; 2195 goto out_err; 2196 case RPC_GARBAGE_ARGS: 2197 dprintk("RPC: %5u %s: server saw garbage\n", 2198 task->tk_pid, __func__); 2199 break; /* retry */ 2200 default: 2201 dprintk("RPC: %5u %s: server accept status: %x\n", 2202 task->tk_pid, __func__, n); 2203 /* Also retry */ 2204 } 2205 2206 out_garbage: 2207 clnt->cl_stats->rpcgarbage++; 2208 if (task->tk_garb_retry) { 2209 task->tk_garb_retry--; 2210 dprintk("RPC: %5u %s: retrying\n", 2211 task->tk_pid, __func__); 2212 task->tk_action = call_bind; 2213 out_retry: 2214 return ERR_PTR(-EAGAIN); 2215 } 2216 out_eio: 2217 error = -EIO; 2218 out_err: 2219 rpc_exit(task, error); 2220 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 2221 __func__, error); 2222 return ERR_PTR(error); 2223 out_overflow: 2224 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 2225 __func__); 2226 goto out_garbage; 2227 } 2228 2229 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2230 { 2231 } 2232 2233 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2234 { 2235 return 0; 2236 } 2237 2238 static struct rpc_procinfo rpcproc_null = { 2239 .p_encode = rpcproc_encode_null, 2240 .p_decode = rpcproc_decode_null, 2241 }; 2242 2243 static int rpc_ping(struct rpc_clnt *clnt) 2244 { 2245 struct rpc_message msg = { 2246 .rpc_proc = &rpcproc_null, 2247 }; 2248 int err; 2249 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2250 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 2251 put_rpccred(msg.rpc_cred); 2252 return err; 2253 } 2254 2255 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2256 { 2257 struct rpc_message msg = { 2258 .rpc_proc = &rpcproc_null, 2259 .rpc_cred = cred, 2260 }; 2261 struct rpc_task_setup task_setup_data = { 2262 .rpc_client = clnt, 2263 .rpc_message = &msg, 2264 .callback_ops = &rpc_default_ops, 2265 .flags = flags, 2266 }; 2267 return rpc_run_task(&task_setup_data); 2268 } 2269 EXPORT_SYMBOL_GPL(rpc_call_null); 2270 2271 #ifdef RPC_DEBUG 2272 static void rpc_show_header(void) 2273 { 2274 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 2275 "-timeout ---ops--\n"); 2276 } 2277 2278 static void rpc_show_task(const struct rpc_clnt *clnt, 2279 const struct rpc_task *task) 2280 { 2281 const char *rpc_waitq = "none"; 2282 2283 if (RPC_IS_QUEUED(task)) 2284 rpc_waitq = rpc_qname(task->tk_waitqueue); 2285 2286 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 2287 task->tk_pid, task->tk_flags, task->tk_status, 2288 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 2289 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task), 2290 task->tk_action, rpc_waitq); 2291 } 2292 2293 void rpc_show_tasks(struct net *net) 2294 { 2295 struct rpc_clnt *clnt; 2296 struct rpc_task *task; 2297 int header = 0; 2298 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 2299 2300 spin_lock(&sn->rpc_client_lock); 2301 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 2302 spin_lock(&clnt->cl_lock); 2303 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 2304 if (!header) { 2305 rpc_show_header(); 2306 header++; 2307 } 2308 rpc_show_task(clnt, task); 2309 } 2310 spin_unlock(&clnt->cl_lock); 2311 } 2312 spin_unlock(&sn->rpc_client_lock); 2313 } 2314 #endif 2315