clnt.c revision aae2006e9b0c294114915c13022fa348e1a88023
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 */ 52static LIST_HEAD(all_clients); 53static DEFINE_SPINLOCK(rpc_client_lock); 54 55static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 56 57 58static void call_start(struct rpc_task *task); 59static void call_reserve(struct rpc_task *task); 60static void call_reserveresult(struct rpc_task *task); 61static void call_allocate(struct rpc_task *task); 62static void call_decode(struct rpc_task *task); 63static void call_bind(struct rpc_task *task); 64static void call_bind_status(struct rpc_task *task); 65static void call_transmit(struct rpc_task *task); 66static void call_status(struct rpc_task *task); 67static void call_transmit_status(struct rpc_task *task); 68static void call_refresh(struct rpc_task *task); 69static void call_refreshresult(struct rpc_task *task); 70static void call_timeout(struct rpc_task *task); 71static void call_connect(struct rpc_task *task); 72static void call_connect_status(struct rpc_task *task); 73 74static __be32 *rpc_encode_header(struct rpc_task *task); 75static __be32 *rpc_verify_header(struct rpc_task *task); 76static int rpc_ping(struct rpc_clnt *clnt, int flags); 77 78static 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 85static 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 92static int 93rpc_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 125static 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 229out_no_auth: 230 if (!IS_ERR(clnt->cl_dentry)) { 231 rpc_rmdir(clnt->cl_dentry); 232 rpc_put_mount(); 233 } 234out_no_path: 235 kfree(clnt->cl_principal); 236out_no_principal: 237 rpc_free_iostats(clnt->cl_metrics); 238out_no_stats: 239 if (clnt->cl_server != clnt->cl_inline_name) 240 kfree(clnt->cl_server); 241 kfree(clnt); 242out_err: 243 xprt_put(xprt); 244out_no_xprt: 245 rpciod_down(); 246out_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 */ 260struct 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} 340EXPORT_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 */ 347struct rpc_clnt * 348rpc_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; 381out_no_path: 382 kfree(new->cl_principal); 383out_no_principal: 384 rpc_free_iostats(new->cl_metrics); 385out_no_stats: 386 kfree(new); 387out_no_clnt: 388 dprintk("RPC: %s: returned error %d\n", __func__, err); 389 return ERR_PTR(err); 390} 391EXPORT_SYMBOL_GPL(rpc_clone_client); 392 393/* 394 * Properly shut down an RPC client, terminating all outstanding 395 * requests. 396 */ 397void 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} 410EXPORT_SYMBOL_GPL(rpc_shutdown_client); 411 412/* 413 * Free an RPC client 414 */ 415static void 416rpc_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); 432out_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 */ 445static void 446rpc_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 */ 469void 470rpc_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 */ 489struct 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 } 513out: 514 return clnt; 515} 516EXPORT_SYMBOL_GPL(rpc_bind_new_program); 517 518/* 519 * Default callback for async RPC calls 520 */ 521static void 522rpc_default_callback(struct rpc_task *task, void *data) 523{ 524} 525 526static 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 */ 534struct 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; 554out: 555 return ret; 556} 557EXPORT_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 */ 565int 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} 585EXPORT_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 */ 595int 596rpc_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} 614EXPORT_SYMBOL_GPL(rpc_call_async); 615 616void 617rpc_call_start(struct rpc_task *task) 618{ 619 task->tk_action = call_start; 620} 621EXPORT_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 */ 631size_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} 642EXPORT_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 */ 650const 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} 660EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 661 662void 663rpc_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} 669EXPORT_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 */ 679size_t rpc_max_payload(struct rpc_clnt *clnt) 680{ 681 return clnt->cl_xprt->max_payload; 682} 683EXPORT_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 */ 690void rpc_force_rebind(struct rpc_clnt *clnt) 691{ 692 if (clnt->cl_autobind) 693 xprt_clear_bound(clnt->cl_xprt); 694} 695EXPORT_SYMBOL_GPL(rpc_force_rebind); 696 697/* 698 * Restart an (async) RPC call from the call_prepare state. 699 * Usually called from within the exit handler. 700 */ 701void 702rpc_restart_call_prepare(struct rpc_task *task) 703{ 704 if (RPC_ASSASSINATED(task)) 705 return; 706 task->tk_action = rpc_prepare_task; 707} 708EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 709 710/* 711 * Restart an (async) RPC call. Usually called from within the 712 * exit handler. 713 */ 714void 715rpc_restart_call(struct rpc_task *task) 716{ 717 if (RPC_ASSASSINATED(task)) 718 return; 719 720 task->tk_action = call_start; 721} 722EXPORT_SYMBOL_GPL(rpc_restart_call); 723 724#ifdef RPC_DEBUG 725static const char *rpc_proc_name(const struct rpc_task *task) 726{ 727 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 728 729 if (proc) { 730 if (proc->p_name) 731 return proc->p_name; 732 else 733 return "NULL"; 734 } else 735 return "no proc"; 736} 737#endif 738 739/* 740 * 0. Initial state 741 * 742 * Other FSM states can be visited zero or more times, but 743 * this state is visited exactly once for each RPC. 744 */ 745static void 746call_start(struct rpc_task *task) 747{ 748 struct rpc_clnt *clnt = task->tk_client; 749 750 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 751 clnt->cl_protname, clnt->cl_vers, 752 rpc_proc_name(task), 753 (RPC_IS_ASYNC(task) ? "async" : "sync")); 754 755 /* Increment call count */ 756 task->tk_msg.rpc_proc->p_count++; 757 clnt->cl_stats->rpccnt++; 758 task->tk_action = call_reserve; 759} 760 761/* 762 * 1. Reserve an RPC call slot 763 */ 764static void 765call_reserve(struct rpc_task *task) 766{ 767 dprint_status(task); 768 769 if (!rpcauth_uptodatecred(task)) { 770 task->tk_action = call_refresh; 771 return; 772 } 773 774 task->tk_status = 0; 775 task->tk_action = call_reserveresult; 776 xprt_reserve(task); 777} 778 779/* 780 * 1b. Grok the result of xprt_reserve() 781 */ 782static void 783call_reserveresult(struct rpc_task *task) 784{ 785 int status = task->tk_status; 786 787 dprint_status(task); 788 789 /* 790 * After a call to xprt_reserve(), we must have either 791 * a request slot or else an error status. 792 */ 793 task->tk_status = 0; 794 if (status >= 0) { 795 if (task->tk_rqstp) { 796 task->tk_action = call_allocate; 797 return; 798 } 799 800 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 801 __func__, status); 802 rpc_exit(task, -EIO); 803 return; 804 } 805 806 /* 807 * Even though there was an error, we may have acquired 808 * a request slot somehow. Make sure not to leak it. 809 */ 810 if (task->tk_rqstp) { 811 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 812 __func__, status); 813 xprt_release(task); 814 } 815 816 switch (status) { 817 case -EAGAIN: /* woken up; retry */ 818 task->tk_action = call_reserve; 819 return; 820 case -EIO: /* probably a shutdown */ 821 break; 822 default: 823 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 824 __func__, status); 825 break; 826 } 827 rpc_exit(task, status); 828} 829 830/* 831 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 832 * (Note: buffer memory is freed in xprt_release). 833 */ 834static void 835call_allocate(struct rpc_task *task) 836{ 837 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack; 838 struct rpc_rqst *req = task->tk_rqstp; 839 struct rpc_xprt *xprt = task->tk_xprt; 840 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 841 842 dprint_status(task); 843 844 task->tk_status = 0; 845 task->tk_action = call_bind; 846 847 if (req->rq_buffer) 848 return; 849 850 if (proc->p_proc != 0) { 851 BUG_ON(proc->p_arglen == 0); 852 if (proc->p_decode != NULL) 853 BUG_ON(proc->p_replen == 0); 854 } 855 856 /* 857 * Calculate the size (in quads) of the RPC call 858 * and reply headers, and convert both values 859 * to byte sizes. 860 */ 861 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 862 req->rq_callsize <<= 2; 863 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 864 req->rq_rcvsize <<= 2; 865 866 req->rq_buffer = xprt->ops->buf_alloc(task, 867 req->rq_callsize + req->rq_rcvsize); 868 if (req->rq_buffer != NULL) 869 return; 870 871 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 872 873 if (RPC_IS_ASYNC(task) || !signalled()) { 874 task->tk_action = call_allocate; 875 rpc_delay(task, HZ>>4); 876 return; 877 } 878 879 rpc_exit(task, -ERESTARTSYS); 880} 881 882static inline int 883rpc_task_need_encode(struct rpc_task *task) 884{ 885 return task->tk_rqstp->rq_snd_buf.len == 0; 886} 887 888static inline void 889rpc_task_force_reencode(struct rpc_task *task) 890{ 891 task->tk_rqstp->rq_snd_buf.len = 0; 892} 893 894static inline void 895rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 896{ 897 buf->head[0].iov_base = start; 898 buf->head[0].iov_len = len; 899 buf->tail[0].iov_len = 0; 900 buf->page_len = 0; 901 buf->flags = 0; 902 buf->len = 0; 903 buf->buflen = len; 904} 905 906/* 907 * 3. Encode arguments of an RPC call 908 */ 909static void 910rpc_xdr_encode(struct rpc_task *task) 911{ 912 struct rpc_rqst *req = task->tk_rqstp; 913 kxdrproc_t encode; 914 __be32 *p; 915 916 dprint_status(task); 917 918 rpc_xdr_buf_init(&req->rq_snd_buf, 919 req->rq_buffer, 920 req->rq_callsize); 921 rpc_xdr_buf_init(&req->rq_rcv_buf, 922 (char *)req->rq_buffer + req->rq_callsize, 923 req->rq_rcvsize); 924 925 p = rpc_encode_header(task); 926 if (p == NULL) { 927 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 928 rpc_exit(task, -EIO); 929 return; 930 } 931 932 encode = task->tk_msg.rpc_proc->p_encode; 933 if (encode == NULL) 934 return; 935 936 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 937 task->tk_msg.rpc_argp); 938} 939 940/* 941 * 4. Get the server port number if not yet set 942 */ 943static void 944call_bind(struct rpc_task *task) 945{ 946 struct rpc_xprt *xprt = task->tk_xprt; 947 948 dprint_status(task); 949 950 task->tk_action = call_connect; 951 if (!xprt_bound(xprt)) { 952 task->tk_action = call_bind_status; 953 task->tk_timeout = xprt->bind_timeout; 954 xprt->ops->rpcbind(task); 955 } 956} 957 958/* 959 * 4a. Sort out bind result 960 */ 961static void 962call_bind_status(struct rpc_task *task) 963{ 964 int status = -EIO; 965 966 if (task->tk_status >= 0) { 967 dprint_status(task); 968 task->tk_status = 0; 969 task->tk_action = call_connect; 970 return; 971 } 972 973 switch (task->tk_status) { 974 case -ENOMEM: 975 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 976 rpc_delay(task, HZ >> 2); 977 goto retry_timeout; 978 case -EACCES: 979 dprintk("RPC: %5u remote rpcbind: RPC program/version " 980 "unavailable\n", task->tk_pid); 981 /* fail immediately if this is an RPC ping */ 982 if (task->tk_msg.rpc_proc->p_proc == 0) { 983 status = -EOPNOTSUPP; 984 break; 985 } 986 rpc_delay(task, 3*HZ); 987 goto retry_timeout; 988 case -ETIMEDOUT: 989 dprintk("RPC: %5u rpcbind request timed out\n", 990 task->tk_pid); 991 goto retry_timeout; 992 case -EPFNOSUPPORT: 993 /* server doesn't support any rpcbind version we know of */ 994 dprintk("RPC: %5u remote rpcbind service unavailable\n", 995 task->tk_pid); 996 break; 997 case -EPROTONOSUPPORT: 998 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 999 task->tk_pid); 1000 task->tk_status = 0; 1001 task->tk_action = call_bind; 1002 return; 1003 default: 1004 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1005 task->tk_pid, -task->tk_status); 1006 } 1007 1008 rpc_exit(task, status); 1009 return; 1010 1011retry_timeout: 1012 task->tk_action = call_timeout; 1013} 1014 1015/* 1016 * 4b. Connect to the RPC server 1017 */ 1018static void 1019call_connect(struct rpc_task *task) 1020{ 1021 struct rpc_xprt *xprt = task->tk_xprt; 1022 1023 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1024 task->tk_pid, xprt, 1025 (xprt_connected(xprt) ? "is" : "is not")); 1026 1027 task->tk_action = call_transmit; 1028 if (!xprt_connected(xprt)) { 1029 task->tk_action = call_connect_status; 1030 if (task->tk_status < 0) 1031 return; 1032 xprt_connect(task); 1033 } 1034} 1035 1036/* 1037 * 4c. Sort out connect result 1038 */ 1039static void 1040call_connect_status(struct rpc_task *task) 1041{ 1042 struct rpc_clnt *clnt = task->tk_client; 1043 int status = task->tk_status; 1044 1045 dprint_status(task); 1046 1047 task->tk_status = 0; 1048 if (status >= 0 || status == -EAGAIN) { 1049 clnt->cl_stats->netreconn++; 1050 task->tk_action = call_transmit; 1051 return; 1052 } 1053 1054 switch (status) { 1055 /* if soft mounted, test if we've timed out */ 1056 case -ETIMEDOUT: 1057 task->tk_action = call_timeout; 1058 break; 1059 default: 1060 rpc_exit(task, -EIO); 1061 } 1062} 1063 1064/* 1065 * 5. Transmit the RPC request, and wait for reply 1066 */ 1067static void 1068call_transmit(struct rpc_task *task) 1069{ 1070 dprint_status(task); 1071 1072 task->tk_action = call_status; 1073 if (task->tk_status < 0) 1074 return; 1075 task->tk_status = xprt_prepare_transmit(task); 1076 if (task->tk_status != 0) 1077 return; 1078 task->tk_action = call_transmit_status; 1079 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1080 if (rpc_task_need_encode(task)) { 1081 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); 1082 rpc_xdr_encode(task); 1083 /* Did the encode result in an error condition? */ 1084 if (task->tk_status != 0) { 1085 /* Was the error nonfatal? */ 1086 if (task->tk_status == -EAGAIN) 1087 rpc_delay(task, HZ >> 4); 1088 else 1089 rpc_exit(task, task->tk_status); 1090 return; 1091 } 1092 } 1093 xprt_transmit(task); 1094 if (task->tk_status < 0) 1095 return; 1096 /* 1097 * On success, ensure that we call xprt_end_transmit() before sleeping 1098 * in order to allow access to the socket to other RPC requests. 1099 */ 1100 call_transmit_status(task); 1101 if (task->tk_msg.rpc_proc->p_decode != NULL) 1102 return; 1103 task->tk_action = rpc_exit_task; 1104 rpc_wake_up_queued_task(&task->tk_xprt->pending, task); 1105} 1106 1107/* 1108 * 5a. Handle cleanup after a transmission 1109 */ 1110static void 1111call_transmit_status(struct rpc_task *task) 1112{ 1113 task->tk_action = call_status; 1114 switch (task->tk_status) { 1115 case -EAGAIN: 1116 break; 1117 default: 1118 xprt_end_transmit(task); 1119 /* 1120 * Special cases: if we've been waiting on the 1121 * socket's write_space() callback, or if the 1122 * socket just returned a connection error, 1123 * then hold onto the transport lock. 1124 */ 1125 case -ECONNREFUSED: 1126 case -ECONNRESET: 1127 case -ENOTCONN: 1128 case -EHOSTDOWN: 1129 case -EHOSTUNREACH: 1130 case -ENETUNREACH: 1131 case -EPIPE: 1132 rpc_task_force_reencode(task); 1133 } 1134} 1135 1136/* 1137 * 6. Sort out the RPC call status 1138 */ 1139static void 1140call_status(struct rpc_task *task) 1141{ 1142 struct rpc_clnt *clnt = task->tk_client; 1143 struct rpc_rqst *req = task->tk_rqstp; 1144 int status; 1145 1146 if (req->rq_received > 0 && !req->rq_bytes_sent) 1147 task->tk_status = req->rq_received; 1148 1149 dprint_status(task); 1150 1151 status = task->tk_status; 1152 if (status >= 0) { 1153 task->tk_action = call_decode; 1154 return; 1155 } 1156 1157 task->tk_status = 0; 1158 switch(status) { 1159 case -EHOSTDOWN: 1160 case -EHOSTUNREACH: 1161 case -ENETUNREACH: 1162 /* 1163 * Delay any retries for 3 seconds, then handle as if it 1164 * were a timeout. 1165 */ 1166 rpc_delay(task, 3*HZ); 1167 case -ETIMEDOUT: 1168 task->tk_action = call_timeout; 1169 if (task->tk_client->cl_discrtry) 1170 xprt_conditional_disconnect(task->tk_xprt, 1171 req->rq_connect_cookie); 1172 break; 1173 case -ECONNRESET: 1174 case -ECONNREFUSED: 1175 rpc_force_rebind(clnt); 1176 rpc_delay(task, 3*HZ); 1177 case -EPIPE: 1178 case -ENOTCONN: 1179 task->tk_action = call_bind; 1180 break; 1181 case -EAGAIN: 1182 task->tk_action = call_transmit; 1183 break; 1184 case -EIO: 1185 /* shutdown or soft timeout */ 1186 rpc_exit(task, status); 1187 break; 1188 default: 1189 if (clnt->cl_chatty) 1190 printk("%s: RPC call returned error %d\n", 1191 clnt->cl_protname, -status); 1192 rpc_exit(task, status); 1193 } 1194} 1195 1196/* 1197 * 6a. Handle RPC timeout 1198 * We do not release the request slot, so we keep using the 1199 * same XID for all retransmits. 1200 */ 1201static void 1202call_timeout(struct rpc_task *task) 1203{ 1204 struct rpc_clnt *clnt = task->tk_client; 1205 1206 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1207 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1208 goto retry; 1209 } 1210 1211 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1212 task->tk_timeouts++; 1213 1214 if (RPC_IS_SOFT(task)) { 1215 if (clnt->cl_chatty) 1216 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1217 clnt->cl_protname, clnt->cl_server); 1218 rpc_exit(task, -EIO); 1219 return; 1220 } 1221 1222 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1223 task->tk_flags |= RPC_CALL_MAJORSEEN; 1224 if (clnt->cl_chatty) 1225 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1226 clnt->cl_protname, clnt->cl_server); 1227 } 1228 rpc_force_rebind(clnt); 1229 /* 1230 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1231 * event? RFC2203 requires the server to drop all such requests. 1232 */ 1233 rpcauth_invalcred(task); 1234 1235retry: 1236 clnt->cl_stats->rpcretrans++; 1237 task->tk_action = call_bind; 1238 task->tk_status = 0; 1239} 1240 1241/* 1242 * 7. Decode the RPC reply 1243 */ 1244static void 1245call_decode(struct rpc_task *task) 1246{ 1247 struct rpc_clnt *clnt = task->tk_client; 1248 struct rpc_rqst *req = task->tk_rqstp; 1249 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 1250 __be32 *p; 1251 1252 dprintk("RPC: %5u call_decode (status %d)\n", 1253 task->tk_pid, task->tk_status); 1254 1255 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1256 if (clnt->cl_chatty) 1257 printk(KERN_NOTICE "%s: server %s OK\n", 1258 clnt->cl_protname, clnt->cl_server); 1259 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1260 } 1261 1262 /* 1263 * Ensure that we see all writes made by xprt_complete_rqst() 1264 * before it changed req->rq_received. 1265 */ 1266 smp_rmb(); 1267 req->rq_rcv_buf.len = req->rq_private_buf.len; 1268 1269 /* Check that the softirq receive buffer is valid */ 1270 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1271 sizeof(req->rq_rcv_buf)) != 0); 1272 1273 if (req->rq_rcv_buf.len < 12) { 1274 if (!RPC_IS_SOFT(task)) { 1275 task->tk_action = call_bind; 1276 clnt->cl_stats->rpcretrans++; 1277 goto out_retry; 1278 } 1279 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1280 clnt->cl_protname, task->tk_status); 1281 task->tk_action = call_timeout; 1282 goto out_retry; 1283 } 1284 1285 p = rpc_verify_header(task); 1286 if (IS_ERR(p)) { 1287 if (p == ERR_PTR(-EAGAIN)) 1288 goto out_retry; 1289 return; 1290 } 1291 1292 task->tk_action = rpc_exit_task; 1293 1294 if (decode) { 1295 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1296 task->tk_msg.rpc_resp); 1297 } 1298 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1299 task->tk_status); 1300 return; 1301out_retry: 1302 task->tk_status = 0; 1303 /* Note: rpc_verify_header() may have freed the RPC slot */ 1304 if (task->tk_rqstp == req) { 1305 req->rq_received = req->rq_rcv_buf.len = 0; 1306 if (task->tk_client->cl_discrtry) 1307 xprt_conditional_disconnect(task->tk_xprt, 1308 req->rq_connect_cookie); 1309 } 1310} 1311 1312/* 1313 * 8. Refresh the credentials if rejected by the server 1314 */ 1315static void 1316call_refresh(struct rpc_task *task) 1317{ 1318 dprint_status(task); 1319 1320 task->tk_action = call_refreshresult; 1321 task->tk_status = 0; 1322 task->tk_client->cl_stats->rpcauthrefresh++; 1323 rpcauth_refreshcred(task); 1324} 1325 1326/* 1327 * 8a. Process the results of a credential refresh 1328 */ 1329static void 1330call_refreshresult(struct rpc_task *task) 1331{ 1332 int status = task->tk_status; 1333 1334 dprint_status(task); 1335 1336 task->tk_status = 0; 1337 task->tk_action = call_reserve; 1338 if (status >= 0 && rpcauth_uptodatecred(task)) 1339 return; 1340 if (status == -EACCES) { 1341 rpc_exit(task, -EACCES); 1342 return; 1343 } 1344 task->tk_action = call_refresh; 1345 if (status != -ETIMEDOUT) 1346 rpc_delay(task, 3*HZ); 1347 return; 1348} 1349 1350static __be32 * 1351rpc_encode_header(struct rpc_task *task) 1352{ 1353 struct rpc_clnt *clnt = task->tk_client; 1354 struct rpc_rqst *req = task->tk_rqstp; 1355 __be32 *p = req->rq_svec[0].iov_base; 1356 1357 /* FIXME: check buffer size? */ 1358 1359 p = xprt_skip_transport_header(task->tk_xprt, p); 1360 *p++ = req->rq_xid; /* XID */ 1361 *p++ = htonl(RPC_CALL); /* CALL */ 1362 *p++ = htonl(RPC_VERSION); /* RPC version */ 1363 *p++ = htonl(clnt->cl_prog); /* program number */ 1364 *p++ = htonl(clnt->cl_vers); /* program version */ 1365 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1366 p = rpcauth_marshcred(task, p); 1367 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1368 return p; 1369} 1370 1371static __be32 * 1372rpc_verify_header(struct rpc_task *task) 1373{ 1374 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1375 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1376 __be32 *p = iov->iov_base; 1377 u32 n; 1378 int error = -EACCES; 1379 1380 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 1381 /* RFC-1014 says that the representation of XDR data must be a 1382 * multiple of four bytes 1383 * - if it isn't pointer subtraction in the NFS client may give 1384 * undefined results 1385 */ 1386 dprintk("RPC: %5u %s: XDR representation not a multiple of" 1387 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 1388 task->tk_rqstp->rq_rcv_buf.len); 1389 goto out_eio; 1390 } 1391 if ((len -= 3) < 0) 1392 goto out_overflow; 1393 p += 1; /* skip XID */ 1394 1395 if ((n = ntohl(*p++)) != RPC_REPLY) { 1396 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 1397 task->tk_pid, __func__, n); 1398 goto out_garbage; 1399 } 1400 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1401 if (--len < 0) 1402 goto out_overflow; 1403 switch ((n = ntohl(*p++))) { 1404 case RPC_AUTH_ERROR: 1405 break; 1406 case RPC_MISMATCH: 1407 dprintk("RPC: %5u %s: RPC call version " 1408 "mismatch!\n", 1409 task->tk_pid, __func__); 1410 error = -EPROTONOSUPPORT; 1411 goto out_err; 1412 default: 1413 dprintk("RPC: %5u %s: RPC call rejected, " 1414 "unknown error: %x\n", 1415 task->tk_pid, __func__, n); 1416 goto out_eio; 1417 } 1418 if (--len < 0) 1419 goto out_overflow; 1420 switch ((n = ntohl(*p++))) { 1421 case RPC_AUTH_REJECTEDCRED: 1422 case RPC_AUTH_REJECTEDVERF: 1423 case RPCSEC_GSS_CREDPROBLEM: 1424 case RPCSEC_GSS_CTXPROBLEM: 1425 if (!task->tk_cred_retry) 1426 break; 1427 task->tk_cred_retry--; 1428 dprintk("RPC: %5u %s: retry stale creds\n", 1429 task->tk_pid, __func__); 1430 rpcauth_invalcred(task); 1431 /* Ensure we obtain a new XID! */ 1432 xprt_release(task); 1433 task->tk_action = call_refresh; 1434 goto out_retry; 1435 case RPC_AUTH_BADCRED: 1436 case RPC_AUTH_BADVERF: 1437 /* possibly garbled cred/verf? */ 1438 if (!task->tk_garb_retry) 1439 break; 1440 task->tk_garb_retry--; 1441 dprintk("RPC: %5u %s: retry garbled creds\n", 1442 task->tk_pid, __func__); 1443 task->tk_action = call_bind; 1444 goto out_retry; 1445 case RPC_AUTH_TOOWEAK: 1446 printk(KERN_NOTICE "RPC: server %s requires stronger " 1447 "authentication.\n", task->tk_client->cl_server); 1448 break; 1449 default: 1450 dprintk("RPC: %5u %s: unknown auth error: %x\n", 1451 task->tk_pid, __func__, n); 1452 error = -EIO; 1453 } 1454 dprintk("RPC: %5u %s: call rejected %d\n", 1455 task->tk_pid, __func__, n); 1456 goto out_err; 1457 } 1458 if (!(p = rpcauth_checkverf(task, p))) { 1459 dprintk("RPC: %5u %s: auth check failed\n", 1460 task->tk_pid, __func__); 1461 goto out_garbage; /* bad verifier, retry */ 1462 } 1463 len = p - (__be32 *)iov->iov_base - 1; 1464 if (len < 0) 1465 goto out_overflow; 1466 switch ((n = ntohl(*p++))) { 1467 case RPC_SUCCESS: 1468 return p; 1469 case RPC_PROG_UNAVAIL: 1470 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", 1471 task->tk_pid, __func__, 1472 (unsigned int)task->tk_client->cl_prog, 1473 task->tk_client->cl_server); 1474 error = -EPFNOSUPPORT; 1475 goto out_err; 1476 case RPC_PROG_MISMATCH: 1477 dprintk("RPC: %5u %s: program %u, version %u unsupported by " 1478 "server %s\n", task->tk_pid, __func__, 1479 (unsigned int)task->tk_client->cl_prog, 1480 (unsigned int)task->tk_client->cl_vers, 1481 task->tk_client->cl_server); 1482 error = -EPROTONOSUPPORT; 1483 goto out_err; 1484 case RPC_PROC_UNAVAIL: 1485 dprintk("RPC: %5u %s: proc %s unsupported by program %u, " 1486 "version %u on server %s\n", 1487 task->tk_pid, __func__, 1488 rpc_proc_name(task), 1489 task->tk_client->cl_prog, 1490 task->tk_client->cl_vers, 1491 task->tk_client->cl_server); 1492 error = -EOPNOTSUPP; 1493 goto out_err; 1494 case RPC_GARBAGE_ARGS: 1495 dprintk("RPC: %5u %s: server saw garbage\n", 1496 task->tk_pid, __func__); 1497 break; /* retry */ 1498 default: 1499 dprintk("RPC: %5u %s: server accept status: %x\n", 1500 task->tk_pid, __func__, n); 1501 /* Also retry */ 1502 } 1503 1504out_garbage: 1505 task->tk_client->cl_stats->rpcgarbage++; 1506 if (task->tk_garb_retry) { 1507 task->tk_garb_retry--; 1508 dprintk("RPC: %5u %s: retrying\n", 1509 task->tk_pid, __func__); 1510 task->tk_action = call_bind; 1511out_retry: 1512 return ERR_PTR(-EAGAIN); 1513 } 1514out_eio: 1515 error = -EIO; 1516out_err: 1517 rpc_exit(task, error); 1518 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 1519 __func__, error); 1520 return ERR_PTR(error); 1521out_overflow: 1522 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 1523 __func__); 1524 goto out_garbage; 1525} 1526 1527static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj) 1528{ 1529 return 0; 1530} 1531 1532static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj) 1533{ 1534 return 0; 1535} 1536 1537static struct rpc_procinfo rpcproc_null = { 1538 .p_encode = rpcproc_encode_null, 1539 .p_decode = rpcproc_decode_null, 1540}; 1541 1542static int rpc_ping(struct rpc_clnt *clnt, int flags) 1543{ 1544 struct rpc_message msg = { 1545 .rpc_proc = &rpcproc_null, 1546 }; 1547 int err; 1548 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1549 err = rpc_call_sync(clnt, &msg, flags); 1550 put_rpccred(msg.rpc_cred); 1551 return err; 1552} 1553 1554struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 1555{ 1556 struct rpc_message msg = { 1557 .rpc_proc = &rpcproc_null, 1558 .rpc_cred = cred, 1559 }; 1560 struct rpc_task_setup task_setup_data = { 1561 .rpc_client = clnt, 1562 .rpc_message = &msg, 1563 .callback_ops = &rpc_default_ops, 1564 .flags = flags, 1565 }; 1566 return rpc_run_task(&task_setup_data); 1567} 1568EXPORT_SYMBOL_GPL(rpc_call_null); 1569 1570#ifdef RPC_DEBUG 1571static void rpc_show_header(void) 1572{ 1573 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 1574 "-timeout ---ops--\n"); 1575} 1576 1577static void rpc_show_task(const struct rpc_clnt *clnt, 1578 const struct rpc_task *task) 1579{ 1580 const char *rpc_waitq = "none"; 1581 char *p, action[KSYM_SYMBOL_LEN]; 1582 1583 if (RPC_IS_QUEUED(task)) 1584 rpc_waitq = rpc_qname(task->tk_waitqueue); 1585 1586 /* map tk_action pointer to a function name; then trim off 1587 * the "+0x0 [sunrpc]" */ 1588 sprint_symbol(action, (unsigned long)task->tk_action); 1589 p = strchr(action, '+'); 1590 if (p) 1591 *p = '\0'; 1592 1593 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%s q:%s\n", 1594 task->tk_pid, task->tk_flags, task->tk_status, 1595 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 1596 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task), 1597 action, rpc_waitq); 1598} 1599 1600void rpc_show_tasks(void) 1601{ 1602 struct rpc_clnt *clnt; 1603 struct rpc_task *task; 1604 int header = 0; 1605 1606 spin_lock(&rpc_client_lock); 1607 list_for_each_entry(clnt, &all_clients, cl_clients) { 1608 spin_lock(&clnt->cl_lock); 1609 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 1610 if (!header) { 1611 rpc_show_header(); 1612 header++; 1613 } 1614 rpc_show_task(clnt, task); 1615 } 1616 spin_unlock(&clnt->cl_lock); 1617 } 1618 spin_unlock(&rpc_client_lock); 1619} 1620#endif 1621