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 * NB: BSD uses a more intelligent approach to guessing when a request 17 * or reply has been lost by keeping the RTO estimate for each procedure. 18 * We currently make do with a constant timeout value. 19 * 20 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 21 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 22 */ 23 24 #include <asm/system.h> 25 26 #include <linux/module.h> 27 #include <linux/types.h> 28 #include <linux/kallsyms.h> 29 #include <linux/mm.h> 30 #include <linux/slab.h> 31 #include <linux/smp_lock.h> 32 #include <linux/utsname.h> 33 #include <linux/workqueue.h> 34 #include <linux/in6.h> 35 36 #include <linux/sunrpc/clnt.h> 37 #include <linux/sunrpc/rpc_pipe_fs.h> 38 #include <linux/sunrpc/metrics.h> 39 40 41 #ifdef RPC_DEBUG 42 # define RPCDBG_FACILITY RPCDBG_CALL 43 #endif 44 45 #define dprint_status(t) \ 46 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 47 __func__, t->tk_status) 48 49 /* 50 * All RPC clients are linked into this list 51 */ 52 static LIST_HEAD(all_clients); 53 static DEFINE_SPINLOCK(rpc_client_lock); 54 55 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 56 57 58 static void call_start(struct rpc_task *task); 59 static void call_reserve(struct rpc_task *task); 60 static void call_reserveresult(struct rpc_task *task); 61 static void call_allocate(struct rpc_task *task); 62 static void call_decode(struct rpc_task *task); 63 static void call_bind(struct rpc_task *task); 64 static void call_bind_status(struct rpc_task *task); 65 static void call_transmit(struct rpc_task *task); 66 static void call_status(struct rpc_task *task); 67 static void call_transmit_status(struct rpc_task *task); 68 static void call_refresh(struct rpc_task *task); 69 static void call_refreshresult(struct rpc_task *task); 70 static void call_timeout(struct rpc_task *task); 71 static void call_connect(struct rpc_task *task); 72 static void call_connect_status(struct rpc_task *task); 73 74 static __be32 *rpc_encode_header(struct rpc_task *task); 75 static __be32 *rpc_verify_header(struct rpc_task *task); 76 static int rpc_ping(struct rpc_clnt *clnt, int flags); 77 78 static void rpc_register_client(struct rpc_clnt *clnt) 79 { 80 spin_lock(&rpc_client_lock); 81 list_add(&clnt->cl_clients, &all_clients); 82 spin_unlock(&rpc_client_lock); 83 } 84 85 static void rpc_unregister_client(struct rpc_clnt *clnt) 86 { 87 spin_lock(&rpc_client_lock); 88 list_del(&clnt->cl_clients); 89 spin_unlock(&rpc_client_lock); 90 } 91 92 static int 93 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name) 94 { 95 static uint32_t clntid; 96 int error; 97 98 clnt->cl_vfsmnt = ERR_PTR(-ENOENT); 99 clnt->cl_dentry = ERR_PTR(-ENOENT); 100 if (dir_name == NULL) 101 return 0; 102 103 clnt->cl_vfsmnt = rpc_get_mount(); 104 if (IS_ERR(clnt->cl_vfsmnt)) 105 return PTR_ERR(clnt->cl_vfsmnt); 106 107 for (;;) { 108 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname), 109 "%s/clnt%x", dir_name, 110 (unsigned int)clntid++); 111 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0'; 112 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt); 113 if (!IS_ERR(clnt->cl_dentry)) 114 return 0; 115 error = PTR_ERR(clnt->cl_dentry); 116 if (error != -EEXIST) { 117 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n", 118 clnt->cl_pathname, error); 119 rpc_put_mount(); 120 return error; 121 } 122 } 123 } 124 125 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt) 126 { 127 struct rpc_program *program = args->program; 128 struct rpc_version *version; 129 struct rpc_clnt *clnt = NULL; 130 struct rpc_auth *auth; 131 int err; 132 size_t len; 133 134 /* sanity check the name before trying to print it */ 135 err = -EINVAL; 136 len = strlen(args->servername); 137 if (len > RPC_MAXNETNAMELEN) 138 goto out_no_rpciod; 139 len++; 140 141 dprintk("RPC: creating %s client for %s (xprt %p)\n", 142 program->name, args->servername, xprt); 143 144 err = rpciod_up(); 145 if (err) 146 goto out_no_rpciod; 147 err = -EINVAL; 148 if (!xprt) 149 goto out_no_xprt; 150 151 if (args->version >= program->nrvers) 152 goto out_err; 153 version = program->version[args->version]; 154 if (version == NULL) 155 goto out_err; 156 157 err = -ENOMEM; 158 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 159 if (!clnt) 160 goto out_err; 161 clnt->cl_parent = clnt; 162 163 clnt->cl_server = clnt->cl_inline_name; 164 if (len > sizeof(clnt->cl_inline_name)) { 165 char *buf = kmalloc(len, GFP_KERNEL); 166 if (buf != NULL) 167 clnt->cl_server = buf; 168 else 169 len = sizeof(clnt->cl_inline_name); 170 } 171 strlcpy(clnt->cl_server, args->servername, len); 172 173 clnt->cl_xprt = xprt; 174 clnt->cl_procinfo = version->procs; 175 clnt->cl_maxproc = version->nrprocs; 176 clnt->cl_protname = program->name; 177 clnt->cl_prog = args->prognumber ? : program->number; 178 clnt->cl_vers = version->number; 179 clnt->cl_stats = program->stats; 180 clnt->cl_metrics = rpc_alloc_iostats(clnt); 181 err = -ENOMEM; 182 if (clnt->cl_metrics == NULL) 183 goto out_no_stats; 184 clnt->cl_program = program; 185 INIT_LIST_HEAD(&clnt->cl_tasks); 186 spin_lock_init(&clnt->cl_lock); 187 188 if (!xprt_bound(clnt->cl_xprt)) 189 clnt->cl_autobind = 1; 190 191 clnt->cl_timeout = xprt->timeout; 192 if (args->timeout != NULL) { 193 memcpy(&clnt->cl_timeout_default, args->timeout, 194 sizeof(clnt->cl_timeout_default)); 195 clnt->cl_timeout = &clnt->cl_timeout_default; 196 } 197 198 clnt->cl_rtt = &clnt->cl_rtt_default; 199 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 200 clnt->cl_principal = NULL; 201 if (args->client_name) { 202 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL); 203 if (!clnt->cl_principal) 204 goto out_no_principal; 205 } 206 207 kref_init(&clnt->cl_kref); 208 209 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 210 if (err < 0) 211 goto out_no_path; 212 213 auth = rpcauth_create(args->authflavor, clnt); 214 if (IS_ERR(auth)) { 215 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 216 args->authflavor); 217 err = PTR_ERR(auth); 218 goto out_no_auth; 219 } 220 221 /* save the nodename */ 222 clnt->cl_nodelen = strlen(init_utsname()->nodename); 223 if (clnt->cl_nodelen > UNX_MAXNODENAME) 224 clnt->cl_nodelen = UNX_MAXNODENAME; 225 memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen); 226 rpc_register_client(clnt); 227 return clnt; 228 229 out_no_auth: 230 if (!IS_ERR(clnt->cl_dentry)) { 231 rpc_rmdir(clnt->cl_dentry); 232 rpc_put_mount(); 233 } 234 out_no_path: 235 kfree(clnt->cl_principal); 236 out_no_principal: 237 rpc_free_iostats(clnt->cl_metrics); 238 out_no_stats: 239 if (clnt->cl_server != clnt->cl_inline_name) 240 kfree(clnt->cl_server); 241 kfree(clnt); 242 out_err: 243 xprt_put(xprt); 244 out_no_xprt: 245 rpciod_down(); 246 out_no_rpciod: 247 return ERR_PTR(err); 248 } 249 250 /* 251 * rpc_create - create an RPC client and transport with one call 252 * @args: rpc_clnt create argument structure 253 * 254 * Creates and initializes an RPC transport and an RPC client. 255 * 256 * It can ping the server in order to determine if it is up, and to see if 257 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 258 * this behavior so asynchronous tasks can also use rpc_create. 259 */ 260 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 261 { 262 struct rpc_xprt *xprt; 263 struct rpc_clnt *clnt; 264 struct xprt_create xprtargs = { 265 .ident = args->protocol, 266 .srcaddr = args->saddress, 267 .dstaddr = args->address, 268 .addrlen = args->addrsize, 269 }; 270 char servername[48]; 271 272 /* 273 * If the caller chooses not to specify a hostname, whip 274 * up a string representation of the passed-in address. 275 */ 276 if (args->servername == NULL) { 277 servername[0] = '\0'; 278 switch (args->address->sa_family) { 279 case AF_INET: { 280 struct sockaddr_in *sin = 281 (struct sockaddr_in *)args->address; 282 snprintf(servername, sizeof(servername), "%pI4", 283 &sin->sin_addr.s_addr); 284 break; 285 } 286 case AF_INET6: { 287 struct sockaddr_in6 *sin = 288 (struct sockaddr_in6 *)args->address; 289 snprintf(servername, sizeof(servername), "%pI6", 290 &sin->sin6_addr); 291 break; 292 } 293 default: 294 /* caller wants default server name, but 295 * address family isn't recognized. */ 296 return ERR_PTR(-EINVAL); 297 } 298 args->servername = servername; 299 } 300 301 xprt = xprt_create_transport(&xprtargs); 302 if (IS_ERR(xprt)) 303 return (struct rpc_clnt *)xprt; 304 305 /* 306 * By default, kernel RPC client connects from a reserved port. 307 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 308 * but it is always enabled for rpciod, which handles the connect 309 * operation. 310 */ 311 xprt->resvport = 1; 312 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 313 xprt->resvport = 0; 314 315 clnt = rpc_new_client(args, xprt); 316 if (IS_ERR(clnt)) 317 return clnt; 318 319 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 320 int err = rpc_ping(clnt, RPC_TASK_SOFT); 321 if (err != 0) { 322 rpc_shutdown_client(clnt); 323 return ERR_PTR(err); 324 } 325 } 326 327 clnt->cl_softrtry = 1; 328 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 329 clnt->cl_softrtry = 0; 330 331 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 332 clnt->cl_autobind = 1; 333 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 334 clnt->cl_discrtry = 1; 335 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 336 clnt->cl_chatty = 1; 337 338 return clnt; 339 } 340 EXPORT_SYMBOL_GPL(rpc_create); 341 342 /* 343 * This function clones the RPC client structure. It allows us to share the 344 * same transport while varying parameters such as the authentication 345 * flavour. 346 */ 347 struct rpc_clnt * 348 rpc_clone_client(struct rpc_clnt *clnt) 349 { 350 struct rpc_clnt *new; 351 int err = -ENOMEM; 352 353 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL); 354 if (!new) 355 goto out_no_clnt; 356 new->cl_parent = clnt; 357 /* Turn off autobind on clones */ 358 new->cl_autobind = 0; 359 INIT_LIST_HEAD(&new->cl_tasks); 360 spin_lock_init(&new->cl_lock); 361 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval); 362 new->cl_metrics = rpc_alloc_iostats(clnt); 363 if (new->cl_metrics == NULL) 364 goto out_no_stats; 365 if (clnt->cl_principal) { 366 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL); 367 if (new->cl_principal == NULL) 368 goto out_no_principal; 369 } 370 kref_init(&new->cl_kref); 371 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); 372 if (err != 0) 373 goto out_no_path; 374 if (new->cl_auth) 375 atomic_inc(&new->cl_auth->au_count); 376 xprt_get(clnt->cl_xprt); 377 kref_get(&clnt->cl_kref); 378 rpc_register_client(new); 379 rpciod_up(); 380 return new; 381 out_no_path: 382 kfree(new->cl_principal); 383 out_no_principal: 384 rpc_free_iostats(new->cl_metrics); 385 out_no_stats: 386 kfree(new); 387 out_no_clnt: 388 dprintk("RPC: %s: returned error %d\n", __func__, err); 389 return ERR_PTR(err); 390 } 391 EXPORT_SYMBOL_GPL(rpc_clone_client); 392 393 /* 394 * Properly shut down an RPC client, terminating all outstanding 395 * requests. 396 */ 397 void rpc_shutdown_client(struct rpc_clnt *clnt) 398 { 399 dprintk("RPC: shutting down %s client for %s\n", 400 clnt->cl_protname, clnt->cl_server); 401 402 while (!list_empty(&clnt->cl_tasks)) { 403 rpc_killall_tasks(clnt); 404 wait_event_timeout(destroy_wait, 405 list_empty(&clnt->cl_tasks), 1*HZ); 406 } 407 408 rpc_release_client(clnt); 409 } 410 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 411 412 /* 413 * Free an RPC client 414 */ 415 static void 416 rpc_free_client(struct kref *kref) 417 { 418 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); 419 420 dprintk("RPC: destroying %s client for %s\n", 421 clnt->cl_protname, clnt->cl_server); 422 if (!IS_ERR(clnt->cl_dentry)) { 423 rpc_rmdir(clnt->cl_dentry); 424 rpc_put_mount(); 425 } 426 if (clnt->cl_parent != clnt) { 427 rpc_release_client(clnt->cl_parent); 428 goto out_free; 429 } 430 if (clnt->cl_server != clnt->cl_inline_name) 431 kfree(clnt->cl_server); 432 out_free: 433 rpc_unregister_client(clnt); 434 rpc_free_iostats(clnt->cl_metrics); 435 kfree(clnt->cl_principal); 436 clnt->cl_metrics = NULL; 437 xprt_put(clnt->cl_xprt); 438 rpciod_down(); 439 kfree(clnt); 440 } 441 442 /* 443 * Free an RPC client 444 */ 445 static void 446 rpc_free_auth(struct kref *kref) 447 { 448 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); 449 450 if (clnt->cl_auth == NULL) { 451 rpc_free_client(kref); 452 return; 453 } 454 455 /* 456 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 457 * release remaining GSS contexts. This mechanism ensures 458 * that it can do so safely. 459 */ 460 kref_init(kref); 461 rpcauth_release(clnt->cl_auth); 462 clnt->cl_auth = NULL; 463 kref_put(kref, rpc_free_client); 464 } 465 466 /* 467 * Release reference to the RPC client 468 */ 469 void 470 rpc_release_client(struct rpc_clnt *clnt) 471 { 472 dprintk("RPC: rpc_release_client(%p)\n", clnt); 473 474 if (list_empty(&clnt->cl_tasks)) 475 wake_up(&destroy_wait); 476 kref_put(&clnt->cl_kref, rpc_free_auth); 477 } 478 479 /** 480 * rpc_bind_new_program - bind a new RPC program to an existing client 481 * @old: old rpc_client 482 * @program: rpc program to set 483 * @vers: rpc program version 484 * 485 * Clones the rpc client and sets up a new RPC program. This is mainly 486 * of use for enabling different RPC programs to share the same transport. 487 * The Sun NFSv2/v3 ACL protocol can do this. 488 */ 489 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 490 struct rpc_program *program, 491 u32 vers) 492 { 493 struct rpc_clnt *clnt; 494 struct rpc_version *version; 495 int err; 496 497 BUG_ON(vers >= program->nrvers || !program->version[vers]); 498 version = program->version[vers]; 499 clnt = rpc_clone_client(old); 500 if (IS_ERR(clnt)) 501 goto out; 502 clnt->cl_procinfo = version->procs; 503 clnt->cl_maxproc = version->nrprocs; 504 clnt->cl_protname = program->name; 505 clnt->cl_prog = program->number; 506 clnt->cl_vers = version->number; 507 clnt->cl_stats = program->stats; 508 err = rpc_ping(clnt, RPC_TASK_SOFT); 509 if (err != 0) { 510 rpc_shutdown_client(clnt); 511 clnt = ERR_PTR(err); 512 } 513 out: 514 return clnt; 515 } 516 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 517 518 /* 519 * Default callback for async RPC calls 520 */ 521 static void 522 rpc_default_callback(struct rpc_task *task, void *data) 523 { 524 } 525 526 static const struct rpc_call_ops rpc_default_ops = { 527 .rpc_call_done = rpc_default_callback, 528 }; 529 530 /** 531 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 532 * @task_setup_data: pointer to task initialisation data 533 */ 534 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 535 { 536 struct rpc_task *task, *ret; 537 538 task = rpc_new_task(task_setup_data); 539 if (task == NULL) { 540 rpc_release_calldata(task_setup_data->callback_ops, 541 task_setup_data->callback_data); 542 ret = ERR_PTR(-ENOMEM); 543 goto out; 544 } 545 546 if (task->tk_status != 0) { 547 ret = ERR_PTR(task->tk_status); 548 rpc_put_task(task); 549 goto out; 550 } 551 atomic_inc(&task->tk_count); 552 rpc_execute(task); 553 ret = task; 554 out: 555 return ret; 556 } 557 EXPORT_SYMBOL_GPL(rpc_run_task); 558 559 /** 560 * rpc_call_sync - Perform a synchronous RPC call 561 * @clnt: pointer to RPC client 562 * @msg: RPC call parameters 563 * @flags: RPC call flags 564 */ 565 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 566 { 567 struct rpc_task *task; 568 struct rpc_task_setup task_setup_data = { 569 .rpc_client = clnt, 570 .rpc_message = msg, 571 .callback_ops = &rpc_default_ops, 572 .flags = flags, 573 }; 574 int status; 575 576 BUG_ON(flags & RPC_TASK_ASYNC); 577 578 task = rpc_run_task(&task_setup_data); 579 if (IS_ERR(task)) 580 return PTR_ERR(task); 581 status = task->tk_status; 582 rpc_put_task(task); 583 return status; 584 } 585 EXPORT_SYMBOL_GPL(rpc_call_sync); 586 587 /** 588 * rpc_call_async - Perform an asynchronous RPC call 589 * @clnt: pointer to RPC client 590 * @msg: RPC call parameters 591 * @flags: RPC call flags 592 * @tk_ops: RPC call ops 593 * @data: user call data 594 */ 595 int 596 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 597 const struct rpc_call_ops *tk_ops, void *data) 598 { 599 struct rpc_task *task; 600 struct rpc_task_setup task_setup_data = { 601 .rpc_client = clnt, 602 .rpc_message = msg, 603 .callback_ops = tk_ops, 604 .callback_data = data, 605 .flags = flags|RPC_TASK_ASYNC, 606 }; 607 608 task = rpc_run_task(&task_setup_data); 609 if (IS_ERR(task)) 610 return PTR_ERR(task); 611 rpc_put_task(task); 612 return 0; 613 } 614 EXPORT_SYMBOL_GPL(rpc_call_async); 615 616 void 617 rpc_call_start(struct rpc_task *task) 618 { 619 task->tk_action = call_start; 620 } 621 EXPORT_SYMBOL_GPL(rpc_call_start); 622 623 /** 624 * rpc_peeraddr - extract remote peer address from clnt's xprt 625 * @clnt: RPC client structure 626 * @buf: target buffer 627 * @bufsize: length of target buffer 628 * 629 * Returns the number of bytes that are actually in the stored address. 630 */ 631 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 632 { 633 size_t bytes; 634 struct rpc_xprt *xprt = clnt->cl_xprt; 635 636 bytes = sizeof(xprt->addr); 637 if (bytes > bufsize) 638 bytes = bufsize; 639 memcpy(buf, &clnt->cl_xprt->addr, bytes); 640 return xprt->addrlen; 641 } 642 EXPORT_SYMBOL_GPL(rpc_peeraddr); 643 644 /** 645 * rpc_peeraddr2str - return remote peer address in printable format 646 * @clnt: RPC client structure 647 * @format: address format 648 * 649 */ 650 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 651 enum rpc_display_format_t format) 652 { 653 struct rpc_xprt *xprt = clnt->cl_xprt; 654 655 if (xprt->address_strings[format] != NULL) 656 return xprt->address_strings[format]; 657 else 658 return "unprintable"; 659 } 660 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 661 662 void 663 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 664 { 665 struct rpc_xprt *xprt = clnt->cl_xprt; 666 if (xprt->ops->set_buffer_size) 667 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 668 } 669 EXPORT_SYMBOL_GPL(rpc_setbufsize); 670 671 /* 672 * Return size of largest payload RPC client can support, in bytes 673 * 674 * For stream transports, this is one RPC record fragment (see RFC 675 * 1831), as we don't support multi-record requests yet. For datagram 676 * transports, this is the size of an IP packet minus the IP, UDP, and 677 * RPC header sizes. 678 */ 679 size_t rpc_max_payload(struct rpc_clnt *clnt) 680 { 681 return clnt->cl_xprt->max_payload; 682 } 683 EXPORT_SYMBOL_GPL(rpc_max_payload); 684 685 /** 686 * rpc_force_rebind - force transport to check that remote port is unchanged 687 * @clnt: client to rebind 688 * 689 */ 690 void rpc_force_rebind(struct rpc_clnt *clnt) 691 { 692 if (clnt->cl_autobind) 693 xprt_clear_bound(clnt->cl_xprt); 694 } 695 EXPORT_SYMBOL_GPL(rpc_force_rebind); 696 697 /* 698 * Restart an (async) RPC call. Usually called from within the 699 * exit handler. 700 */ 701 void 702 rpc_restart_call(struct rpc_task *task) 703 { 704 if (RPC_ASSASSINATED(task)) 705 return; 706 707 task->tk_action = call_start; 708 } 709 EXPORT_SYMBOL_GPL(rpc_restart_call); 710 711 #ifdef RPC_DEBUG 712 static const char *rpc_proc_name(const struct rpc_task *task) 713 { 714 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 715 716 if (proc) { 717 if (proc->p_name) 718 return proc->p_name; 719 else 720 return "NULL"; 721 } else 722 return "no proc"; 723 } 724 #endif 725 726 /* 727 * 0. Initial state 728 * 729 * Other FSM states can be visited zero or more times, but 730 * this state is visited exactly once for each RPC. 731 */ 732 static void 733 call_start(struct rpc_task *task) 734 { 735 struct rpc_clnt *clnt = task->tk_client; 736 737 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 738 clnt->cl_protname, clnt->cl_vers, 739 rpc_proc_name(task), 740 (RPC_IS_ASYNC(task) ? "async" : "sync")); 741 742 /* Increment call count */ 743 task->tk_msg.rpc_proc->p_count++; 744 clnt->cl_stats->rpccnt++; 745 task->tk_action = call_reserve; 746 } 747 748 /* 749 * 1. Reserve an RPC call slot 750 */ 751 static void 752 call_reserve(struct rpc_task *task) 753 { 754 dprint_status(task); 755 756 if (!rpcauth_uptodatecred(task)) { 757 task->tk_action = call_refresh; 758 return; 759 } 760 761 task->tk_status = 0; 762 task->tk_action = call_reserveresult; 763 xprt_reserve(task); 764 } 765 766 /* 767 * 1b. Grok the result of xprt_reserve() 768 */ 769 static void 770 call_reserveresult(struct rpc_task *task) 771 { 772 int status = task->tk_status; 773 774 dprint_status(task); 775 776 /* 777 * After a call to xprt_reserve(), we must have either 778 * a request slot or else an error status. 779 */ 780 task->tk_status = 0; 781 if (status >= 0) { 782 if (task->tk_rqstp) { 783 task->tk_action = call_allocate; 784 return; 785 } 786 787 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 788 __func__, status); 789 rpc_exit(task, -EIO); 790 return; 791 } 792 793 /* 794 * Even though there was an error, we may have acquired 795 * a request slot somehow. Make sure not to leak it. 796 */ 797 if (task->tk_rqstp) { 798 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 799 __func__, status); 800 xprt_release(task); 801 } 802 803 switch (status) { 804 case -EAGAIN: /* woken up; retry */ 805 task->tk_action = call_reserve; 806 return; 807 case -EIO: /* probably a shutdown */ 808 break; 809 default: 810 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 811 __func__, status); 812 break; 813 } 814 rpc_exit(task, status); 815 } 816 817 /* 818 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 819 * (Note: buffer memory is freed in xprt_release). 820 */ 821 static void 822 call_allocate(struct rpc_task *task) 823 { 824 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack; 825 struct rpc_rqst *req = task->tk_rqstp; 826 struct rpc_xprt *xprt = task->tk_xprt; 827 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 828 829 dprint_status(task); 830 831 task->tk_status = 0; 832 task->tk_action = call_bind; 833 834 if (req->rq_buffer) 835 return; 836 837 if (proc->p_proc != 0) { 838 BUG_ON(proc->p_arglen == 0); 839 if (proc->p_decode != NULL) 840 BUG_ON(proc->p_replen == 0); 841 } 842 843 /* 844 * Calculate the size (in quads) of the RPC call 845 * and reply headers, and convert both values 846 * to byte sizes. 847 */ 848 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 849 req->rq_callsize <<= 2; 850 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 851 req->rq_rcvsize <<= 2; 852 853 req->rq_buffer = xprt->ops->buf_alloc(task, 854 req->rq_callsize + req->rq_rcvsize); 855 if (req->rq_buffer != NULL) 856 return; 857 858 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 859 860 if (RPC_IS_ASYNC(task) || !signalled()) { 861 task->tk_action = call_allocate; 862 rpc_delay(task, HZ>>4); 863 return; 864 } 865 866 rpc_exit(task, -ERESTARTSYS); 867 } 868 869 static inline int 870 rpc_task_need_encode(struct rpc_task *task) 871 { 872 return task->tk_rqstp->rq_snd_buf.len == 0; 873 } 874 875 static inline void 876 rpc_task_force_reencode(struct rpc_task *task) 877 { 878 task->tk_rqstp->rq_snd_buf.len = 0; 879 } 880 881 static inline void 882 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 883 { 884 buf->head[0].iov_base = start; 885 buf->head[0].iov_len = len; 886 buf->tail[0].iov_len = 0; 887 buf->page_len = 0; 888 buf->flags = 0; 889 buf->len = 0; 890 buf->buflen = len; 891 } 892 893 /* 894 * 3. Encode arguments of an RPC call 895 */ 896 static void 897 rpc_xdr_encode(struct rpc_task *task) 898 { 899 struct rpc_rqst *req = task->tk_rqstp; 900 kxdrproc_t encode; 901 __be32 *p; 902 903 dprint_status(task); 904 905 rpc_xdr_buf_init(&req->rq_snd_buf, 906 req->rq_buffer, 907 req->rq_callsize); 908 rpc_xdr_buf_init(&req->rq_rcv_buf, 909 (char *)req->rq_buffer + req->rq_callsize, 910 req->rq_rcvsize); 911 912 p = rpc_encode_header(task); 913 if (p == NULL) { 914 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 915 rpc_exit(task, -EIO); 916 return; 917 } 918 919 encode = task->tk_msg.rpc_proc->p_encode; 920 if (encode == NULL) 921 return; 922 923 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 924 task->tk_msg.rpc_argp); 925 } 926 927 /* 928 * 4. Get the server port number if not yet set 929 */ 930 static void 931 call_bind(struct rpc_task *task) 932 { 933 struct rpc_xprt *xprt = task->tk_xprt; 934 935 dprint_status(task); 936 937 task->tk_action = call_connect; 938 if (!xprt_bound(xprt)) { 939 task->tk_action = call_bind_status; 940 task->tk_timeout = xprt->bind_timeout; 941 xprt->ops->rpcbind(task); 942 } 943 } 944 945 /* 946 * 4a. Sort out bind result 947 */ 948 static void 949 call_bind_status(struct rpc_task *task) 950 { 951 int status = -EIO; 952 953 if (task->tk_status >= 0) { 954 dprint_status(task); 955 task->tk_status = 0; 956 task->tk_action = call_connect; 957 return; 958 } 959 960 switch (task->tk_status) { 961 case -ENOMEM: 962 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 963 rpc_delay(task, HZ >> 2); 964 goto retry_timeout; 965 case -EACCES: 966 dprintk("RPC: %5u remote rpcbind: RPC program/version " 967 "unavailable\n", task->tk_pid); 968 /* fail immediately if this is an RPC ping */ 969 if (task->tk_msg.rpc_proc->p_proc == 0) { 970 status = -EOPNOTSUPP; 971 break; 972 } 973 rpc_delay(task, 3*HZ); 974 goto retry_timeout; 975 case -ETIMEDOUT: 976 dprintk("RPC: %5u rpcbind request timed out\n", 977 task->tk_pid); 978 goto retry_timeout; 979 case -EPFNOSUPPORT: 980 /* server doesn't support any rpcbind version we know of */ 981 dprintk("RPC: %5u remote rpcbind service unavailable\n", 982 task->tk_pid); 983 break; 984 case -EPROTONOSUPPORT: 985 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 986 task->tk_pid); 987 task->tk_status = 0; 988 task->tk_action = call_bind; 989 return; 990 default: 991 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 992 task->tk_pid, -task->tk_status); 993 } 994 995 rpc_exit(task, status); 996 return; 997 998 retry_timeout: 999 task->tk_action = call_timeout; 1000 } 1001 1002 /* 1003 * 4b. Connect to the RPC server 1004 */ 1005 static void 1006 call_connect(struct rpc_task *task) 1007 { 1008 struct rpc_xprt *xprt = task->tk_xprt; 1009 1010 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1011 task->tk_pid, xprt, 1012 (xprt_connected(xprt) ? "is" : "is not")); 1013 1014 task->tk_action = call_transmit; 1015 if (!xprt_connected(xprt)) { 1016 task->tk_action = call_connect_status; 1017 if (task->tk_status < 0) 1018 return; 1019 xprt_connect(task); 1020 } 1021 } 1022 1023 /* 1024 * 4c. Sort out connect result 1025 */ 1026 static void 1027 call_connect_status(struct rpc_task *task) 1028 { 1029 struct rpc_clnt *clnt = task->tk_client; 1030 int status = task->tk_status; 1031 1032 dprint_status(task); 1033 1034 task->tk_status = 0; 1035 if (status >= 0) { 1036 clnt->cl_stats->netreconn++; 1037 task->tk_action = call_transmit; 1038 return; 1039 } 1040 1041 /* Something failed: remote service port may have changed */ 1042 rpc_force_rebind(clnt); 1043 1044 switch (status) { 1045 case -ENOTCONN: 1046 case -EAGAIN: 1047 task->tk_action = call_bind; 1048 if (!RPC_IS_SOFT(task)) 1049 return; 1050 /* if soft mounted, test if we've timed out */ 1051 case -ETIMEDOUT: 1052 task->tk_action = call_timeout; 1053 return; 1054 } 1055 rpc_exit(task, -EIO); 1056 } 1057 1058 /* 1059 * 5. Transmit the RPC request, and wait for reply 1060 */ 1061 static void 1062 call_transmit(struct rpc_task *task) 1063 { 1064 dprint_status(task); 1065 1066 task->tk_action = call_status; 1067 if (task->tk_status < 0) 1068 return; 1069 task->tk_status = xprt_prepare_transmit(task); 1070 if (task->tk_status != 0) 1071 return; 1072 task->tk_action = call_transmit_status; 1073 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1074 if (rpc_task_need_encode(task)) { 1075 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); 1076 rpc_xdr_encode(task); 1077 /* Did the encode result in an error condition? */ 1078 if (task->tk_status != 0) { 1079 /* Was the error nonfatal? */ 1080 if (task->tk_status == -EAGAIN) 1081 rpc_delay(task, HZ >> 4); 1082 else 1083 rpc_exit(task, task->tk_status); 1084 return; 1085 } 1086 } 1087 xprt_transmit(task); 1088 if (task->tk_status < 0) 1089 return; 1090 /* 1091 * On success, ensure that we call xprt_end_transmit() before sleeping 1092 * in order to allow access to the socket to other RPC requests. 1093 */ 1094 call_transmit_status(task); 1095 if (task->tk_msg.rpc_proc->p_decode != NULL) 1096 return; 1097 task->tk_action = rpc_exit_task; 1098 rpc_wake_up_queued_task(&task->tk_xprt->pending, task); 1099 } 1100 1101 /* 1102 * 5a. Handle cleanup after a transmission 1103 */ 1104 static void 1105 call_transmit_status(struct rpc_task *task) 1106 { 1107 task->tk_action = call_status; 1108 /* 1109 * Special case: if we've been waiting on the socket's write_space() 1110 * callback, then don't call xprt_end_transmit(). 1111 */ 1112 if (task->tk_status == -EAGAIN) 1113 return; 1114 xprt_end_transmit(task); 1115 rpc_task_force_reencode(task); 1116 } 1117 1118 /* 1119 * 6. Sort out the RPC call status 1120 */ 1121 static void 1122 call_status(struct rpc_task *task) 1123 { 1124 struct rpc_clnt *clnt = task->tk_client; 1125 struct rpc_rqst *req = task->tk_rqstp; 1126 int status; 1127 1128 if (req->rq_received > 0 && !req->rq_bytes_sent) 1129 task->tk_status = req->rq_received; 1130 1131 dprint_status(task); 1132 1133 status = task->tk_status; 1134 if (status >= 0) { 1135 task->tk_action = call_decode; 1136 return; 1137 } 1138 1139 task->tk_status = 0; 1140 switch(status) { 1141 case -EHOSTDOWN: 1142 case -EHOSTUNREACH: 1143 case -ENETUNREACH: 1144 /* 1145 * Delay any retries for 3 seconds, then handle as if it 1146 * were a timeout. 1147 */ 1148 rpc_delay(task, 3*HZ); 1149 case -ETIMEDOUT: 1150 task->tk_action = call_timeout; 1151 if (task->tk_client->cl_discrtry) 1152 xprt_conditional_disconnect(task->tk_xprt, 1153 req->rq_connect_cookie); 1154 break; 1155 case -ECONNREFUSED: 1156 case -ENOTCONN: 1157 rpc_force_rebind(clnt); 1158 task->tk_action = call_bind; 1159 break; 1160 case -EAGAIN: 1161 task->tk_action = call_transmit; 1162 break; 1163 case -EIO: 1164 /* shutdown or soft timeout */ 1165 rpc_exit(task, status); 1166 break; 1167 default: 1168 if (clnt->cl_chatty) 1169 printk("%s: RPC call returned error %d\n", 1170 clnt->cl_protname, -status); 1171 rpc_exit(task, status); 1172 } 1173 } 1174 1175 /* 1176 * 6a. Handle RPC timeout 1177 * We do not release the request slot, so we keep using the 1178 * same XID for all retransmits. 1179 */ 1180 static void 1181 call_timeout(struct rpc_task *task) 1182 { 1183 struct rpc_clnt *clnt = task->tk_client; 1184 1185 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1186 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1187 goto retry; 1188 } 1189 1190 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1191 task->tk_timeouts++; 1192 1193 if (RPC_IS_SOFT(task)) { 1194 if (clnt->cl_chatty) 1195 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1196 clnt->cl_protname, clnt->cl_server); 1197 rpc_exit(task, -EIO); 1198 return; 1199 } 1200 1201 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1202 task->tk_flags |= RPC_CALL_MAJORSEEN; 1203 if (clnt->cl_chatty) 1204 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1205 clnt->cl_protname, clnt->cl_server); 1206 } 1207 rpc_force_rebind(clnt); 1208 /* 1209 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1210 * event? RFC2203 requires the server to drop all such requests. 1211 */ 1212 rpcauth_invalcred(task); 1213 1214 retry: 1215 clnt->cl_stats->rpcretrans++; 1216 task->tk_action = call_bind; 1217 task->tk_status = 0; 1218 } 1219 1220 /* 1221 * 7. Decode the RPC reply 1222 */ 1223 static void 1224 call_decode(struct rpc_task *task) 1225 { 1226 struct rpc_clnt *clnt = task->tk_client; 1227 struct rpc_rqst *req = task->tk_rqstp; 1228 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 1229 __be32 *p; 1230 1231 dprintk("RPC: %5u call_decode (status %d)\n", 1232 task->tk_pid, task->tk_status); 1233 1234 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1235 if (clnt->cl_chatty) 1236 printk(KERN_NOTICE "%s: server %s OK\n", 1237 clnt->cl_protname, clnt->cl_server); 1238 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1239 } 1240 1241 /* 1242 * Ensure that we see all writes made by xprt_complete_rqst() 1243 * before it changed req->rq_received. 1244 */ 1245 smp_rmb(); 1246 req->rq_rcv_buf.len = req->rq_private_buf.len; 1247 1248 /* Check that the softirq receive buffer is valid */ 1249 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1250 sizeof(req->rq_rcv_buf)) != 0); 1251 1252 if (req->rq_rcv_buf.len < 12) { 1253 if (!RPC_IS_SOFT(task)) { 1254 task->tk_action = call_bind; 1255 clnt->cl_stats->rpcretrans++; 1256 goto out_retry; 1257 } 1258 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1259 clnt->cl_protname, task->tk_status); 1260 task->tk_action = call_timeout; 1261 goto out_retry; 1262 } 1263 1264 p = rpc_verify_header(task); 1265 if (IS_ERR(p)) { 1266 if (p == ERR_PTR(-EAGAIN)) 1267 goto out_retry; 1268 return; 1269 } 1270 1271 task->tk_action = rpc_exit_task; 1272 1273 if (decode) { 1274 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1275 task->tk_msg.rpc_resp); 1276 } 1277 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1278 task->tk_status); 1279 return; 1280 out_retry: 1281 task->tk_status = 0; 1282 /* Note: rpc_verify_header() may have freed the RPC slot */ 1283 if (task->tk_rqstp == req) { 1284 req->rq_received = req->rq_rcv_buf.len = 0; 1285 if (task->tk_client->cl_discrtry) 1286 xprt_conditional_disconnect(task->tk_xprt, 1287 req->rq_connect_cookie); 1288 } 1289 } 1290 1291 /* 1292 * 8. Refresh the credentials if rejected by the server 1293 */ 1294 static void 1295 call_refresh(struct rpc_task *task) 1296 { 1297 dprint_status(task); 1298 1299 task->tk_action = call_refreshresult; 1300 task->tk_status = 0; 1301 task->tk_client->cl_stats->rpcauthrefresh++; 1302 rpcauth_refreshcred(task); 1303 } 1304 1305 /* 1306 * 8a. Process the results of a credential refresh 1307 */ 1308 static void 1309 call_refreshresult(struct rpc_task *task) 1310 { 1311 int status = task->tk_status; 1312 1313 dprint_status(task); 1314 1315 task->tk_status = 0; 1316 task->tk_action = call_reserve; 1317 if (status >= 0 && rpcauth_uptodatecred(task)) 1318 return; 1319 if (status == -EACCES) { 1320 rpc_exit(task, -EACCES); 1321 return; 1322 } 1323 task->tk_action = call_refresh; 1324 if (status != -ETIMEDOUT) 1325 rpc_delay(task, 3*HZ); 1326 return; 1327 } 1328 1329 static __be32 * 1330 rpc_encode_header(struct rpc_task *task) 1331 { 1332 struct rpc_clnt *clnt = task->tk_client; 1333 struct rpc_rqst *req = task->tk_rqstp; 1334 __be32 *p = req->rq_svec[0].iov_base; 1335 1336 /* FIXME: check buffer size? */ 1337 1338 p = xprt_skip_transport_header(task->tk_xprt, p); 1339 *p++ = req->rq_xid; /* XID */ 1340 *p++ = htonl(RPC_CALL); /* CALL */ 1341 *p++ = htonl(RPC_VERSION); /* RPC version */ 1342 *p++ = htonl(clnt->cl_prog); /* program number */ 1343 *p++ = htonl(clnt->cl_vers); /* program version */ 1344 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1345 p = rpcauth_marshcred(task, p); 1346 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1347 return p; 1348 } 1349 1350 static __be32 * 1351 rpc_verify_header(struct rpc_task *task) 1352 { 1353 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1354 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1355 __be32 *p = iov->iov_base; 1356 u32 n; 1357 int error = -EACCES; 1358 1359 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 1360 /* RFC-1014 says that the representation of XDR data must be a 1361 * multiple of four bytes 1362 * - if it isn't pointer subtraction in the NFS client may give 1363 * undefined results 1364 */ 1365 dprintk("RPC: %5u %s: XDR representation not a multiple of" 1366 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 1367 task->tk_rqstp->rq_rcv_buf.len); 1368 goto out_eio; 1369 } 1370 if ((len -= 3) < 0) 1371 goto out_overflow; 1372 p += 1; /* skip XID */ 1373 1374 if ((n = ntohl(*p++)) != RPC_REPLY) { 1375 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 1376 task->tk_pid, __func__, n); 1377 goto out_garbage; 1378 } 1379 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1380 if (--len < 0) 1381 goto out_overflow; 1382 switch ((n = ntohl(*p++))) { 1383 case RPC_AUTH_ERROR: 1384 break; 1385 case RPC_MISMATCH: 1386 dprintk("RPC: %5u %s: RPC call version " 1387 "mismatch!\n", 1388 task->tk_pid, __func__); 1389 error = -EPROTONOSUPPORT; 1390 goto out_err; 1391 default: 1392 dprintk("RPC: %5u %s: RPC call rejected, " 1393 "unknown error: %x\n", 1394 task->tk_pid, __func__, n); 1395 goto out_eio; 1396 } 1397 if (--len < 0) 1398 goto out_overflow; 1399 switch ((n = ntohl(*p++))) { 1400 case RPC_AUTH_REJECTEDCRED: 1401 case RPC_AUTH_REJECTEDVERF: 1402 case RPCSEC_GSS_CREDPROBLEM: 1403 case RPCSEC_GSS_CTXPROBLEM: 1404 if (!task->tk_cred_retry) 1405 break; 1406 task->tk_cred_retry--; 1407 dprintk("RPC: %5u %s: retry stale creds\n", 1408 task->tk_pid, __func__); 1409 rpcauth_invalcred(task); 1410 /* Ensure we obtain a new XID! */ 1411 xprt_release(task); 1412 task->tk_action = call_refresh; 1413 goto out_retry; 1414 case RPC_AUTH_BADCRED: 1415 case RPC_AUTH_BADVERF: 1416 /* possibly garbled cred/verf? */ 1417 if (!task->tk_garb_retry) 1418 break; 1419 task->tk_garb_retry--; 1420 dprintk("RPC: %5u %s: retry garbled creds\n", 1421 task->tk_pid, __func__); 1422 task->tk_action = call_bind; 1423 goto out_retry; 1424 case RPC_AUTH_TOOWEAK: 1425 printk(KERN_NOTICE "RPC: server %s requires stronger " 1426 "authentication.\n", task->tk_client->cl_server); 1427 break; 1428 default: 1429 dprintk("RPC: %5u %s: unknown auth error: %x\n", 1430 task->tk_pid, __func__, n); 1431 error = -EIO; 1432 } 1433 dprintk("RPC: %5u %s: call rejected %d\n", 1434 task->tk_pid, __func__, n); 1435 goto out_err; 1436 } 1437 if (!(p = rpcauth_checkverf(task, p))) { 1438 dprintk("RPC: %5u %s: auth check failed\n", 1439 task->tk_pid, __func__); 1440 goto out_garbage; /* bad verifier, retry */ 1441 } 1442 len = p - (__be32 *)iov->iov_base - 1; 1443 if (len < 0) 1444 goto out_overflow; 1445 switch ((n = ntohl(*p++))) { 1446 case RPC_SUCCESS: 1447 return p; 1448 case RPC_PROG_UNAVAIL: 1449 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", 1450 task->tk_pid, __func__, 1451 (unsigned int)task->tk_client->cl_prog, 1452 task->tk_client->cl_server); 1453 error = -EPFNOSUPPORT; 1454 goto out_err; 1455 case RPC_PROG_MISMATCH: 1456 dprintk("RPC: %5u %s: program %u, version %u unsupported by " 1457 "server %s\n", task->tk_pid, __func__, 1458 (unsigned int)task->tk_client->cl_prog, 1459 (unsigned int)task->tk_client->cl_vers, 1460 task->tk_client->cl_server); 1461 error = -EPROTONOSUPPORT; 1462 goto out_err; 1463 case RPC_PROC_UNAVAIL: 1464 dprintk("RPC: %5u %s: proc %s unsupported by program %u, " 1465 "version %u on server %s\n", 1466 task->tk_pid, __func__, 1467 rpc_proc_name(task), 1468 task->tk_client->cl_prog, 1469 task->tk_client->cl_vers, 1470 task->tk_client->cl_server); 1471 error = -EOPNOTSUPP; 1472 goto out_err; 1473 case RPC_GARBAGE_ARGS: 1474 dprintk("RPC: %5u %s: server saw garbage\n", 1475 task->tk_pid, __func__); 1476 break; /* retry */ 1477 default: 1478 dprintk("RPC: %5u %s: server accept status: %x\n", 1479 task->tk_pid, __func__, n); 1480 /* Also retry */ 1481 } 1482 1483 out_garbage: 1484 task->tk_client->cl_stats->rpcgarbage++; 1485 if (task->tk_garb_retry) { 1486 task->tk_garb_retry--; 1487 dprintk("RPC: %5u %s: retrying\n", 1488 task->tk_pid, __func__); 1489 task->tk_action = call_bind; 1490 out_retry: 1491 return ERR_PTR(-EAGAIN); 1492 } 1493 out_eio: 1494 error = -EIO; 1495 out_err: 1496 rpc_exit(task, error); 1497 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 1498 __func__, error); 1499 return ERR_PTR(error); 1500 out_overflow: 1501 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 1502 __func__); 1503 goto out_garbage; 1504 } 1505 1506 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj) 1507 { 1508 return 0; 1509 } 1510 1511 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj) 1512 { 1513 return 0; 1514 } 1515 1516 static struct rpc_procinfo rpcproc_null = { 1517 .p_encode = rpcproc_encode_null, 1518 .p_decode = rpcproc_decode_null, 1519 }; 1520 1521 static int rpc_ping(struct rpc_clnt *clnt, int flags) 1522 { 1523 struct rpc_message msg = { 1524 .rpc_proc = &rpcproc_null, 1525 }; 1526 int err; 1527 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1528 err = rpc_call_sync(clnt, &msg, flags); 1529 put_rpccred(msg.rpc_cred); 1530 return err; 1531 } 1532 1533 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 1534 { 1535 struct rpc_message msg = { 1536 .rpc_proc = &rpcproc_null, 1537 .rpc_cred = cred, 1538 }; 1539 struct rpc_task_setup task_setup_data = { 1540 .rpc_client = clnt, 1541 .rpc_message = &msg, 1542 .callback_ops = &rpc_default_ops, 1543 .flags = flags, 1544 }; 1545 return rpc_run_task(&task_setup_data); 1546 } 1547 EXPORT_SYMBOL_GPL(rpc_call_null); 1548 1549 #ifdef RPC_DEBUG 1550 static void rpc_show_header(void) 1551 { 1552 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 1553 "-timeout ---ops--\n"); 1554 } 1555 1556 static void rpc_show_task(const struct rpc_clnt *clnt, 1557 const struct rpc_task *task) 1558 { 1559 const char *rpc_waitq = "none"; 1560 char *p, action[KSYM_SYMBOL_LEN]; 1561 1562 if (RPC_IS_QUEUED(task)) 1563 rpc_waitq = rpc_qname(task->tk_waitqueue); 1564 1565 /* map tk_action pointer to a function name; then trim off 1566 * the "+0x0 [sunrpc]" */ 1567 sprint_symbol(action, (unsigned long)task->tk_action); 1568 p = strchr(action, '+'); 1569 if (p) 1570 *p = '\0'; 1571 1572 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%s q:%s\n", 1573 task->tk_pid, task->tk_flags, task->tk_status, 1574 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 1575 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task), 1576 action, rpc_waitq); 1577 } 1578 1579 void rpc_show_tasks(void) 1580 { 1581 struct rpc_clnt *clnt; 1582 struct rpc_task *task; 1583 int header = 0; 1584 1585 spin_lock(&rpc_client_lock); 1586 list_for_each_entry(clnt, &all_clients, cl_clients) { 1587 spin_lock(&clnt->cl_lock); 1588 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 1589 if (!header) { 1590 rpc_show_header(); 1591 header++; 1592 } 1593 rpc_show_task(clnt, task); 1594 } 1595 spin_unlock(&clnt->cl_lock); 1596 } 1597 spin_unlock(&rpc_client_lock); 1598 } 1599 #endif 1600