clnt.c revision 698b6d088e8a5d907596c689d5ae9109611c5b59
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/mm.h> 29#include <linux/slab.h> 30#include <linux/smp_lock.h> 31#include <linux/utsname.h> 32#include <linux/workqueue.h> 33#include <linux/in6.h> 34 35#include <linux/sunrpc/clnt.h> 36#include <linux/sunrpc/rpc_pipe_fs.h> 37#include <linux/sunrpc/metrics.h> 38 39 40#ifdef RPC_DEBUG 41# define RPCDBG_FACILITY RPCDBG_CALL 42#endif 43 44#define dprint_status(t) \ 45 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 46 __FUNCTION__, t->tk_status) 47 48/* 49 * All RPC clients are linked into this list 50 */ 51static LIST_HEAD(all_clients); 52static DEFINE_SPINLOCK(rpc_client_lock); 53 54static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 55 56 57static void call_start(struct rpc_task *task); 58static void call_reserve(struct rpc_task *task); 59static void call_reserveresult(struct rpc_task *task); 60static void call_allocate(struct rpc_task *task); 61static void call_encode(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); 73static __be32 * call_header(struct rpc_task *task); 74static __be32 * call_verify(struct rpc_task *task); 75 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 = 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_rtt = &clnt->cl_rtt_default; 192 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval); 193 194 kref_init(&clnt->cl_kref); 195 196 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 197 if (err < 0) 198 goto out_no_path; 199 200 auth = rpcauth_create(args->authflavor, clnt); 201 if (IS_ERR(auth)) { 202 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 203 args->authflavor); 204 err = PTR_ERR(auth); 205 goto out_no_auth; 206 } 207 208 /* save the nodename */ 209 clnt->cl_nodelen = strlen(utsname()->nodename); 210 if (clnt->cl_nodelen > UNX_MAXNODENAME) 211 clnt->cl_nodelen = UNX_MAXNODENAME; 212 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen); 213 rpc_register_client(clnt); 214 return clnt; 215 216out_no_auth: 217 if (!IS_ERR(clnt->cl_dentry)) { 218 rpc_rmdir(clnt->cl_dentry); 219 rpc_put_mount(); 220 } 221out_no_path: 222 rpc_free_iostats(clnt->cl_metrics); 223out_no_stats: 224 if (clnt->cl_server != clnt->cl_inline_name) 225 kfree(clnt->cl_server); 226 kfree(clnt); 227out_err: 228 xprt_put(xprt); 229out_no_xprt: 230 rpciod_down(); 231out_no_rpciod: 232 return ERR_PTR(err); 233} 234 235/* 236 * rpc_create - create an RPC client and transport with one call 237 * @args: rpc_clnt create argument structure 238 * 239 * Creates and initializes an RPC transport and an RPC client. 240 * 241 * It can ping the server in order to determine if it is up, and to see if 242 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 243 * this behavior so asynchronous tasks can also use rpc_create. 244 */ 245struct rpc_clnt *rpc_create(struct rpc_create_args *args) 246{ 247 struct rpc_xprt *xprt; 248 struct rpc_clnt *clnt; 249 struct xprt_create xprtargs = { 250 .ident = args->protocol, 251 .srcaddr = args->saddress, 252 .dstaddr = args->address, 253 .addrlen = args->addrsize, 254 .timeout = args->timeout 255 }; 256 char servername[48]; 257 258 xprt = xprt_create_transport(&xprtargs); 259 if (IS_ERR(xprt)) 260 return (struct rpc_clnt *)xprt; 261 262 /* 263 * If the caller chooses not to specify a hostname, whip 264 * up a string representation of the passed-in address. 265 */ 266 if (args->servername == NULL) { 267 servername[0] = '\0'; 268 switch (args->address->sa_family) { 269 case AF_INET: { 270 struct sockaddr_in *sin = 271 (struct sockaddr_in *)args->address; 272 snprintf(servername, sizeof(servername), NIPQUAD_FMT, 273 NIPQUAD(sin->sin_addr.s_addr)); 274 break; 275 } 276 case AF_INET6: { 277 struct sockaddr_in6 *sin = 278 (struct sockaddr_in6 *)args->address; 279 snprintf(servername, sizeof(servername), NIP6_FMT, 280 NIP6(sin->sin6_addr)); 281 break; 282 } 283 default: 284 /* caller wants default server name, but 285 * address family isn't recognized. */ 286 return ERR_PTR(-EINVAL); 287 } 288 args->servername = servername; 289 } 290 291 xprt = xprt_create_transport(&xprtargs); 292 if (IS_ERR(xprt)) 293 return (struct rpc_clnt *)xprt; 294 295 /* 296 * By default, kernel RPC client connects from a reserved port. 297 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 298 * but it is always enabled for rpciod, which handles the connect 299 * operation. 300 */ 301 xprt->resvport = 1; 302 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 303 xprt->resvport = 0; 304 305 clnt = rpc_new_client(args, xprt); 306 if (IS_ERR(clnt)) 307 return clnt; 308 309 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 310 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 311 if (err != 0) { 312 rpc_shutdown_client(clnt); 313 return ERR_PTR(err); 314 } 315 } 316 317 clnt->cl_softrtry = 1; 318 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 319 clnt->cl_softrtry = 0; 320 321 if (args->flags & RPC_CLNT_CREATE_INTR) 322 clnt->cl_intr = 1; 323 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 324 clnt->cl_autobind = 1; 325 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 326 clnt->cl_discrtry = 1; 327 328 return clnt; 329} 330EXPORT_SYMBOL_GPL(rpc_create); 331 332/* 333 * This function clones the RPC client structure. It allows us to share the 334 * same transport while varying parameters such as the authentication 335 * flavour. 336 */ 337struct rpc_clnt * 338rpc_clone_client(struct rpc_clnt *clnt) 339{ 340 struct rpc_clnt *new; 341 int err = -ENOMEM; 342 343 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL); 344 if (!new) 345 goto out_no_clnt; 346 new->cl_parent = clnt; 347 /* Turn off autobind on clones */ 348 new->cl_autobind = 0; 349 INIT_LIST_HEAD(&new->cl_tasks); 350 spin_lock_init(&new->cl_lock); 351 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval); 352 new->cl_metrics = rpc_alloc_iostats(clnt); 353 if (new->cl_metrics == NULL) 354 goto out_no_stats; 355 kref_init(&new->cl_kref); 356 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name); 357 if (err != 0) 358 goto out_no_path; 359 if (new->cl_auth) 360 atomic_inc(&new->cl_auth->au_count); 361 xprt_get(clnt->cl_xprt); 362 kref_get(&clnt->cl_kref); 363 rpc_register_client(new); 364 rpciod_up(); 365 return new; 366out_no_path: 367 rpc_free_iostats(new->cl_metrics); 368out_no_stats: 369 kfree(new); 370out_no_clnt: 371 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err); 372 return ERR_PTR(err); 373} 374EXPORT_SYMBOL_GPL(rpc_clone_client); 375 376/* 377 * Properly shut down an RPC client, terminating all outstanding 378 * requests. 379 */ 380void rpc_shutdown_client(struct rpc_clnt *clnt) 381{ 382 dprintk("RPC: shutting down %s client for %s\n", 383 clnt->cl_protname, clnt->cl_server); 384 385 while (!list_empty(&clnt->cl_tasks)) { 386 rpc_killall_tasks(clnt); 387 wait_event_timeout(destroy_wait, 388 list_empty(&clnt->cl_tasks), 1*HZ); 389 } 390 391 rpc_release_client(clnt); 392} 393EXPORT_SYMBOL_GPL(rpc_shutdown_client); 394 395/* 396 * Free an RPC client 397 */ 398static void 399rpc_free_client(struct kref *kref) 400{ 401 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); 402 403 dprintk("RPC: destroying %s client for %s\n", 404 clnt->cl_protname, clnt->cl_server); 405 if (!IS_ERR(clnt->cl_dentry)) { 406 rpc_rmdir(clnt->cl_dentry); 407 rpc_put_mount(); 408 } 409 if (clnt->cl_parent != clnt) { 410 rpc_release_client(clnt->cl_parent); 411 goto out_free; 412 } 413 if (clnt->cl_server != clnt->cl_inline_name) 414 kfree(clnt->cl_server); 415out_free: 416 rpc_unregister_client(clnt); 417 rpc_free_iostats(clnt->cl_metrics); 418 clnt->cl_metrics = NULL; 419 xprt_put(clnt->cl_xprt); 420 rpciod_down(); 421 kfree(clnt); 422} 423 424/* 425 * Free an RPC client 426 */ 427static void 428rpc_free_auth(struct kref *kref) 429{ 430 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref); 431 432 if (clnt->cl_auth == NULL) { 433 rpc_free_client(kref); 434 return; 435 } 436 437 /* 438 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 439 * release remaining GSS contexts. This mechanism ensures 440 * that it can do so safely. 441 */ 442 kref_init(kref); 443 rpcauth_release(clnt->cl_auth); 444 clnt->cl_auth = NULL; 445 kref_put(kref, rpc_free_client); 446} 447 448/* 449 * Release reference to the RPC client 450 */ 451void 452rpc_release_client(struct rpc_clnt *clnt) 453{ 454 dprintk("RPC: rpc_release_client(%p)\n", clnt); 455 456 if (list_empty(&clnt->cl_tasks)) 457 wake_up(&destroy_wait); 458 kref_put(&clnt->cl_kref, rpc_free_auth); 459} 460 461/** 462 * rpc_bind_new_program - bind a new RPC program to an existing client 463 * @old - old rpc_client 464 * @program - rpc program to set 465 * @vers - rpc program version 466 * 467 * Clones the rpc client and sets up a new RPC program. This is mainly 468 * of use for enabling different RPC programs to share the same transport. 469 * The Sun NFSv2/v3 ACL protocol can do this. 470 */ 471struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 472 struct rpc_program *program, 473 u32 vers) 474{ 475 struct rpc_clnt *clnt; 476 struct rpc_version *version; 477 int err; 478 479 BUG_ON(vers >= program->nrvers || !program->version[vers]); 480 version = program->version[vers]; 481 clnt = rpc_clone_client(old); 482 if (IS_ERR(clnt)) 483 goto out; 484 clnt->cl_procinfo = version->procs; 485 clnt->cl_maxproc = version->nrprocs; 486 clnt->cl_protname = program->name; 487 clnt->cl_prog = program->number; 488 clnt->cl_vers = version->number; 489 clnt->cl_stats = program->stats; 490 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 491 if (err != 0) { 492 rpc_shutdown_client(clnt); 493 clnt = ERR_PTR(err); 494 } 495out: 496 return clnt; 497} 498EXPORT_SYMBOL_GPL(rpc_bind_new_program); 499 500/* 501 * Default callback for async RPC calls 502 */ 503static void 504rpc_default_callback(struct rpc_task *task, void *data) 505{ 506} 507 508static const struct rpc_call_ops rpc_default_ops = { 509 .rpc_call_done = rpc_default_callback, 510}; 511 512/* 513 * Export the signal mask handling for synchronous code that 514 * sleeps on RPC calls 515 */ 516#define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM)) 517 518static void rpc_save_sigmask(sigset_t *oldset, int intr) 519{ 520 unsigned long sigallow = sigmask(SIGKILL); 521 sigset_t sigmask; 522 523 /* Block all signals except those listed in sigallow */ 524 if (intr) 525 sigallow |= RPC_INTR_SIGNALS; 526 siginitsetinv(&sigmask, sigallow); 527 sigprocmask(SIG_BLOCK, &sigmask, oldset); 528} 529 530static void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset) 531{ 532 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task)); 533} 534 535static void rpc_restore_sigmask(sigset_t *oldset) 536{ 537 sigprocmask(SIG_SETMASK, oldset, NULL); 538} 539 540void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset) 541{ 542 rpc_save_sigmask(oldset, clnt->cl_intr); 543} 544EXPORT_SYMBOL_GPL(rpc_clnt_sigmask); 545 546void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset) 547{ 548 rpc_restore_sigmask(oldset); 549} 550EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask); 551 552/** 553 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 554 * @task_setup_data: pointer to task initialisation data 555 */ 556struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 557{ 558 struct rpc_task *task, *ret; 559 sigset_t oldset; 560 561 task = rpc_new_task(task_setup_data); 562 if (task == NULL) { 563 rpc_release_calldata(task_setup_data->callback_ops, 564 task_setup_data->callback_data); 565 ret = ERR_PTR(-ENOMEM); 566 goto out; 567 } 568 569 if (task->tk_status != 0) { 570 ret = ERR_PTR(task->tk_status); 571 rpc_put_task(task); 572 goto out; 573 } 574 atomic_inc(&task->tk_count); 575 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */ 576 rpc_task_sigmask(task, &oldset); 577 rpc_execute(task); 578 rpc_restore_sigmask(&oldset); 579 ret = task; 580out: 581 return ret; 582} 583EXPORT_SYMBOL_GPL(rpc_run_task); 584 585/** 586 * rpc_call_sync - Perform a synchronous RPC call 587 * @clnt: pointer to RPC client 588 * @msg: RPC call parameters 589 * @flags: RPC call flags 590 */ 591int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) 592{ 593 struct rpc_task *task; 594 struct rpc_task_setup task_setup_data = { 595 .rpc_client = clnt, 596 .rpc_message = msg, 597 .callback_ops = &rpc_default_ops, 598 .flags = flags, 599 }; 600 int status; 601 602 BUG_ON(flags & RPC_TASK_ASYNC); 603 604 task = rpc_run_task(&task_setup_data); 605 if (IS_ERR(task)) 606 return PTR_ERR(task); 607 status = task->tk_status; 608 rpc_put_task(task); 609 return status; 610} 611EXPORT_SYMBOL_GPL(rpc_call_sync); 612 613/** 614 * rpc_call_async - Perform an asynchronous RPC call 615 * @clnt: pointer to RPC client 616 * @msg: RPC call parameters 617 * @flags: RPC call flags 618 * @ops: RPC call ops 619 * @data: user call data 620 */ 621int 622rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags, 623 const struct rpc_call_ops *tk_ops, void *data) 624{ 625 struct rpc_task *task; 626 struct rpc_task_setup task_setup_data = { 627 .rpc_client = clnt, 628 .rpc_message = msg, 629 .callback_ops = tk_ops, 630 .callback_data = data, 631 .flags = flags|RPC_TASK_ASYNC, 632 }; 633 634 task = rpc_run_task(&task_setup_data); 635 if (IS_ERR(task)) 636 return PTR_ERR(task); 637 rpc_put_task(task); 638 return 0; 639} 640EXPORT_SYMBOL_GPL(rpc_call_async); 641 642void 643rpc_call_start(struct rpc_task *task) 644{ 645 task->tk_action = call_start; 646} 647EXPORT_SYMBOL_GPL(rpc_call_start); 648 649/** 650 * rpc_peeraddr - extract remote peer address from clnt's xprt 651 * @clnt: RPC client structure 652 * @buf: target buffer 653 * @size: length of target buffer 654 * 655 * Returns the number of bytes that are actually in the stored address. 656 */ 657size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 658{ 659 size_t bytes; 660 struct rpc_xprt *xprt = clnt->cl_xprt; 661 662 bytes = sizeof(xprt->addr); 663 if (bytes > bufsize) 664 bytes = bufsize; 665 memcpy(buf, &clnt->cl_xprt->addr, bytes); 666 return xprt->addrlen; 667} 668EXPORT_SYMBOL_GPL(rpc_peeraddr); 669 670/** 671 * rpc_peeraddr2str - return remote peer address in printable format 672 * @clnt: RPC client structure 673 * @format: address format 674 * 675 */ 676char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format) 677{ 678 struct rpc_xprt *xprt = clnt->cl_xprt; 679 680 if (xprt->address_strings[format] != NULL) 681 return xprt->address_strings[format]; 682 else 683 return "unprintable"; 684} 685EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 686 687void 688rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 689{ 690 struct rpc_xprt *xprt = clnt->cl_xprt; 691 if (xprt->ops->set_buffer_size) 692 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 693} 694EXPORT_SYMBOL_GPL(rpc_setbufsize); 695 696/* 697 * Return size of largest payload RPC client can support, in bytes 698 * 699 * For stream transports, this is one RPC record fragment (see RFC 700 * 1831), as we don't support multi-record requests yet. For datagram 701 * transports, this is the size of an IP packet minus the IP, UDP, and 702 * RPC header sizes. 703 */ 704size_t rpc_max_payload(struct rpc_clnt *clnt) 705{ 706 return clnt->cl_xprt->max_payload; 707} 708EXPORT_SYMBOL_GPL(rpc_max_payload); 709 710/** 711 * rpc_force_rebind - force transport to check that remote port is unchanged 712 * @clnt: client to rebind 713 * 714 */ 715void rpc_force_rebind(struct rpc_clnt *clnt) 716{ 717 if (clnt->cl_autobind) 718 xprt_clear_bound(clnt->cl_xprt); 719} 720EXPORT_SYMBOL_GPL(rpc_force_rebind); 721 722/* 723 * Restart an (async) RPC call. Usually called from within the 724 * exit handler. 725 */ 726void 727rpc_restart_call(struct rpc_task *task) 728{ 729 if (RPC_ASSASSINATED(task)) 730 return; 731 732 task->tk_action = call_start; 733} 734EXPORT_SYMBOL_GPL(rpc_restart_call); 735 736/* 737 * 0. Initial state 738 * 739 * Other FSM states can be visited zero or more times, but 740 * this state is visited exactly once for each RPC. 741 */ 742static void 743call_start(struct rpc_task *task) 744{ 745 struct rpc_clnt *clnt = task->tk_client; 746 747 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid, 748 clnt->cl_protname, clnt->cl_vers, 749 task->tk_msg.rpc_proc->p_proc, 750 (RPC_IS_ASYNC(task) ? "async" : "sync")); 751 752 /* Increment call count */ 753 task->tk_msg.rpc_proc->p_count++; 754 clnt->cl_stats->rpccnt++; 755 task->tk_action = call_reserve; 756} 757 758/* 759 * 1. Reserve an RPC call slot 760 */ 761static void 762call_reserve(struct rpc_task *task) 763{ 764 dprint_status(task); 765 766 if (!rpcauth_uptodatecred(task)) { 767 task->tk_action = call_refresh; 768 return; 769 } 770 771 task->tk_status = 0; 772 task->tk_action = call_reserveresult; 773 xprt_reserve(task); 774} 775 776/* 777 * 1b. Grok the result of xprt_reserve() 778 */ 779static void 780call_reserveresult(struct rpc_task *task) 781{ 782 int status = task->tk_status; 783 784 dprint_status(task); 785 786 /* 787 * After a call to xprt_reserve(), we must have either 788 * a request slot or else an error status. 789 */ 790 task->tk_status = 0; 791 if (status >= 0) { 792 if (task->tk_rqstp) { 793 task->tk_action = call_allocate; 794 return; 795 } 796 797 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 798 __FUNCTION__, status); 799 rpc_exit(task, -EIO); 800 return; 801 } 802 803 /* 804 * Even though there was an error, we may have acquired 805 * a request slot somehow. Make sure not to leak it. 806 */ 807 if (task->tk_rqstp) { 808 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 809 __FUNCTION__, status); 810 xprt_release(task); 811 } 812 813 switch (status) { 814 case -EAGAIN: /* woken up; retry */ 815 task->tk_action = call_reserve; 816 return; 817 case -EIO: /* probably a shutdown */ 818 break; 819 default: 820 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 821 __FUNCTION__, status); 822 break; 823 } 824 rpc_exit(task, status); 825} 826 827/* 828 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 829 * (Note: buffer memory is freed in xprt_release). 830 */ 831static void 832call_allocate(struct rpc_task *task) 833{ 834 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack; 835 struct rpc_rqst *req = task->tk_rqstp; 836 struct rpc_xprt *xprt = task->tk_xprt; 837 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 838 839 dprint_status(task); 840 841 task->tk_status = 0; 842 task->tk_action = call_bind; 843 844 if (req->rq_buffer) 845 return; 846 847 if (proc->p_proc != 0) { 848 BUG_ON(proc->p_arglen == 0); 849 if (proc->p_decode != NULL) 850 BUG_ON(proc->p_replen == 0); 851 } 852 853 /* 854 * Calculate the size (in quads) of the RPC call 855 * and reply headers, and convert both values 856 * to byte sizes. 857 */ 858 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 859 req->rq_callsize <<= 2; 860 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 861 req->rq_rcvsize <<= 2; 862 863 req->rq_buffer = xprt->ops->buf_alloc(task, 864 req->rq_callsize + req->rq_rcvsize); 865 if (req->rq_buffer != NULL) 866 return; 867 868 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 869 870 if (RPC_IS_ASYNC(task) || !signalled()) { 871 task->tk_action = call_allocate; 872 rpc_delay(task, HZ>>4); 873 return; 874 } 875 876 rpc_exit(task, -ERESTARTSYS); 877} 878 879static inline int 880rpc_task_need_encode(struct rpc_task *task) 881{ 882 return task->tk_rqstp->rq_snd_buf.len == 0; 883} 884 885static inline void 886rpc_task_force_reencode(struct rpc_task *task) 887{ 888 task->tk_rqstp->rq_snd_buf.len = 0; 889} 890 891static inline void 892rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 893{ 894 buf->head[0].iov_base = start; 895 buf->head[0].iov_len = len; 896 buf->tail[0].iov_len = 0; 897 buf->page_len = 0; 898 buf->flags = 0; 899 buf->len = 0; 900 buf->buflen = len; 901} 902 903/* 904 * 3. Encode arguments of an RPC call 905 */ 906static void 907call_encode(struct rpc_task *task) 908{ 909 struct rpc_rqst *req = task->tk_rqstp; 910 kxdrproc_t encode; 911 __be32 *p; 912 913 dprint_status(task); 914 915 rpc_xdr_buf_init(&req->rq_snd_buf, 916 req->rq_buffer, 917 req->rq_callsize); 918 rpc_xdr_buf_init(&req->rq_rcv_buf, 919 (char *)req->rq_buffer + req->rq_callsize, 920 req->rq_rcvsize); 921 922 /* Encode header and provided arguments */ 923 encode = task->tk_msg.rpc_proc->p_encode; 924 if (!(p = call_header(task))) { 925 printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); 926 rpc_exit(task, -EIO); 927 return; 928 } 929 if (encode == NULL) 930 return; 931 932 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 933 task->tk_msg.rpc_argp); 934 if (task->tk_status == -ENOMEM) { 935 /* XXX: Is this sane? */ 936 rpc_delay(task, 3*HZ); 937 task->tk_status = -EAGAIN; 938 } 939} 940 941/* 942 * 4. Get the server port number if not yet set 943 */ 944static void 945call_bind(struct rpc_task *task) 946{ 947 struct rpc_xprt *xprt = task->tk_xprt; 948 949 dprint_status(task); 950 951 task->tk_action = call_connect; 952 if (!xprt_bound(xprt)) { 953 task->tk_action = call_bind_status; 954 task->tk_timeout = xprt->bind_timeout; 955 xprt->ops->rpcbind(task); 956 } 957} 958 959/* 960 * 4a. Sort out bind result 961 */ 962static void 963call_bind_status(struct rpc_task *task) 964{ 965 int status = -EIO; 966 967 if (task->tk_status >= 0) { 968 dprint_status(task); 969 task->tk_status = 0; 970 task->tk_action = call_connect; 971 return; 972 } 973 974 switch (task->tk_status) { 975 case -EAGAIN: 976 dprintk("RPC: %5u rpcbind waiting for another request " 977 "to finish\n", task->tk_pid); 978 /* avoid busy-waiting here -- could be a network outage. */ 979 rpc_delay(task, 5*HZ); 980 goto retry_timeout; 981 case -EACCES: 982 dprintk("RPC: %5u remote rpcbind: RPC program/version " 983 "unavailable\n", task->tk_pid); 984 /* fail immediately if this is an RPC ping */ 985 if (task->tk_msg.rpc_proc->p_proc == 0) { 986 status = -EOPNOTSUPP; 987 break; 988 } 989 rpc_delay(task, 3*HZ); 990 goto retry_timeout; 991 case -ETIMEDOUT: 992 dprintk("RPC: %5u rpcbind request timed out\n", 993 task->tk_pid); 994 goto retry_timeout; 995 case -EPFNOSUPPORT: 996 /* server doesn't support any rpcbind version we know of */ 997 dprintk("RPC: %5u remote rpcbind service unavailable\n", 998 task->tk_pid); 999 break; 1000 case -EPROTONOSUPPORT: 1001 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1002 task->tk_pid); 1003 task->tk_status = 0; 1004 task->tk_action = call_bind; 1005 return; 1006 default: 1007 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1008 task->tk_pid, -task->tk_status); 1009 } 1010 1011 rpc_exit(task, status); 1012 return; 1013 1014retry_timeout: 1015 task->tk_action = call_timeout; 1016} 1017 1018/* 1019 * 4b. Connect to the RPC server 1020 */ 1021static void 1022call_connect(struct rpc_task *task) 1023{ 1024 struct rpc_xprt *xprt = task->tk_xprt; 1025 1026 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1027 task->tk_pid, xprt, 1028 (xprt_connected(xprt) ? "is" : "is not")); 1029 1030 task->tk_action = call_transmit; 1031 if (!xprt_connected(xprt)) { 1032 task->tk_action = call_connect_status; 1033 if (task->tk_status < 0) 1034 return; 1035 xprt_connect(task); 1036 } 1037} 1038 1039/* 1040 * 4c. Sort out connect result 1041 */ 1042static void 1043call_connect_status(struct rpc_task *task) 1044{ 1045 struct rpc_clnt *clnt = task->tk_client; 1046 int status = task->tk_status; 1047 1048 dprint_status(task); 1049 1050 task->tk_status = 0; 1051 if (status >= 0) { 1052 clnt->cl_stats->netreconn++; 1053 task->tk_action = call_transmit; 1054 return; 1055 } 1056 1057 /* Something failed: remote service port may have changed */ 1058 rpc_force_rebind(clnt); 1059 1060 switch (status) { 1061 case -ENOTCONN: 1062 case -EAGAIN: 1063 task->tk_action = call_bind; 1064 if (!RPC_IS_SOFT(task)) 1065 return; 1066 /* if soft mounted, test if we've timed out */ 1067 case -ETIMEDOUT: 1068 task->tk_action = call_timeout; 1069 return; 1070 } 1071 rpc_exit(task, -EIO); 1072} 1073 1074/* 1075 * 5. Transmit the RPC request, and wait for reply 1076 */ 1077static void 1078call_transmit(struct rpc_task *task) 1079{ 1080 dprint_status(task); 1081 1082 task->tk_action = call_status; 1083 if (task->tk_status < 0) 1084 return; 1085 task->tk_status = xprt_prepare_transmit(task); 1086 if (task->tk_status != 0) 1087 return; 1088 task->tk_action = call_transmit_status; 1089 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1090 if (rpc_task_need_encode(task)) { 1091 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); 1092 call_encode(task); 1093 /* Did the encode result in an error condition? */ 1094 if (task->tk_status != 0) 1095 return; 1096 } 1097 xprt_transmit(task); 1098 if (task->tk_status < 0) 1099 return; 1100 /* 1101 * On success, ensure that we call xprt_end_transmit() before sleeping 1102 * in order to allow access to the socket to other RPC requests. 1103 */ 1104 call_transmit_status(task); 1105 if (task->tk_msg.rpc_proc->p_decode != NULL) 1106 return; 1107 task->tk_action = rpc_exit_task; 1108 rpc_wake_up_task(task); 1109} 1110 1111/* 1112 * 5a. Handle cleanup after a transmission 1113 */ 1114static void 1115call_transmit_status(struct rpc_task *task) 1116{ 1117 task->tk_action = call_status; 1118 /* 1119 * Special case: if we've been waiting on the socket's write_space() 1120 * callback, then don't call xprt_end_transmit(). 1121 */ 1122 if (task->tk_status == -EAGAIN) 1123 return; 1124 xprt_end_transmit(task); 1125 rpc_task_force_reencode(task); 1126} 1127 1128/* 1129 * 6. Sort out the RPC call status 1130 */ 1131static void 1132call_status(struct rpc_task *task) 1133{ 1134 struct rpc_clnt *clnt = task->tk_client; 1135 struct rpc_rqst *req = task->tk_rqstp; 1136 int status; 1137 1138 if (req->rq_received > 0 && !req->rq_bytes_sent) 1139 task->tk_status = req->rq_received; 1140 1141 dprint_status(task); 1142 1143 status = task->tk_status; 1144 if (status >= 0) { 1145 task->tk_action = call_decode; 1146 return; 1147 } 1148 1149 task->tk_status = 0; 1150 switch(status) { 1151 case -EHOSTDOWN: 1152 case -EHOSTUNREACH: 1153 case -ENETUNREACH: 1154 /* 1155 * Delay any retries for 3 seconds, then handle as if it 1156 * were a timeout. 1157 */ 1158 rpc_delay(task, 3*HZ); 1159 case -ETIMEDOUT: 1160 task->tk_action = call_timeout; 1161 if (task->tk_client->cl_discrtry) 1162 xprt_force_disconnect(task->tk_xprt); 1163 break; 1164 case -ECONNREFUSED: 1165 case -ENOTCONN: 1166 rpc_force_rebind(clnt); 1167 task->tk_action = call_bind; 1168 break; 1169 case -EAGAIN: 1170 task->tk_action = call_transmit; 1171 break; 1172 case -EIO: 1173 /* shutdown or soft timeout */ 1174 rpc_exit(task, status); 1175 break; 1176 default: 1177 printk("%s: RPC call returned error %d\n", 1178 clnt->cl_protname, -status); 1179 rpc_exit(task, status); 1180 } 1181} 1182 1183/* 1184 * 6a. Handle RPC timeout 1185 * We do not release the request slot, so we keep using the 1186 * same XID for all retransmits. 1187 */ 1188static void 1189call_timeout(struct rpc_task *task) 1190{ 1191 struct rpc_clnt *clnt = task->tk_client; 1192 1193 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1194 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1195 goto retry; 1196 } 1197 1198 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1199 task->tk_timeouts++; 1200 1201 if (RPC_IS_SOFT(task)) { 1202 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1203 clnt->cl_protname, clnt->cl_server); 1204 rpc_exit(task, -EIO); 1205 return; 1206 } 1207 1208 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1209 task->tk_flags |= RPC_CALL_MAJORSEEN; 1210 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1211 clnt->cl_protname, clnt->cl_server); 1212 } 1213 rpc_force_rebind(clnt); 1214 1215retry: 1216 clnt->cl_stats->rpcretrans++; 1217 task->tk_action = call_bind; 1218 task->tk_status = 0; 1219} 1220 1221/* 1222 * 7. Decode the RPC reply 1223 */ 1224static void 1225call_decode(struct rpc_task *task) 1226{ 1227 struct rpc_clnt *clnt = task->tk_client; 1228 struct rpc_rqst *req = task->tk_rqstp; 1229 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 1230 __be32 *p; 1231 1232 dprintk("RPC: %5u call_decode (status %d)\n", 1233 task->tk_pid, task->tk_status); 1234 1235 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 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 if (task->tk_status < 12) { 1242 if (!RPC_IS_SOFT(task)) { 1243 task->tk_action = call_bind; 1244 clnt->cl_stats->rpcretrans++; 1245 goto out_retry; 1246 } 1247 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1248 clnt->cl_protname, task->tk_status); 1249 task->tk_action = call_timeout; 1250 goto out_retry; 1251 } 1252 1253 /* 1254 * Ensure that we see all writes made by xprt_complete_rqst() 1255 * before it changed req->rq_received. 1256 */ 1257 smp_rmb(); 1258 req->rq_rcv_buf.len = req->rq_private_buf.len; 1259 1260 /* Check that the softirq receive buffer is valid */ 1261 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1262 sizeof(req->rq_rcv_buf)) != 0); 1263 1264 /* Verify the RPC header */ 1265 p = call_verify(task); 1266 if (IS_ERR(p)) { 1267 if (p == ERR_PTR(-EAGAIN)) 1268 goto out_retry; 1269 return; 1270 } 1271 1272 task->tk_action = rpc_exit_task; 1273 1274 if (decode) { 1275 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1276 task->tk_msg.rpc_resp); 1277 } 1278 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1279 task->tk_status); 1280 return; 1281out_retry: 1282 req->rq_received = req->rq_private_buf.len = 0; 1283 task->tk_status = 0; 1284 if (task->tk_client->cl_discrtry) 1285 xprt_force_disconnect(task->tk_xprt); 1286} 1287 1288/* 1289 * 8. Refresh the credentials if rejected by the server 1290 */ 1291static void 1292call_refresh(struct rpc_task *task) 1293{ 1294 dprint_status(task); 1295 1296 task->tk_action = call_refreshresult; 1297 task->tk_status = 0; 1298 task->tk_client->cl_stats->rpcauthrefresh++; 1299 rpcauth_refreshcred(task); 1300} 1301 1302/* 1303 * 8a. Process the results of a credential refresh 1304 */ 1305static void 1306call_refreshresult(struct rpc_task *task) 1307{ 1308 int status = task->tk_status; 1309 1310 dprint_status(task); 1311 1312 task->tk_status = 0; 1313 task->tk_action = call_reserve; 1314 if (status >= 0 && rpcauth_uptodatecred(task)) 1315 return; 1316 if (status == -EACCES) { 1317 rpc_exit(task, -EACCES); 1318 return; 1319 } 1320 task->tk_action = call_refresh; 1321 if (status != -ETIMEDOUT) 1322 rpc_delay(task, 3*HZ); 1323 return; 1324} 1325 1326/* 1327 * Call header serialization 1328 */ 1329static __be32 * 1330call_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/* 1351 * Reply header verification 1352 */ 1353static __be32 * 1354call_verify(struct rpc_task *task) 1355{ 1356 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1357 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1358 __be32 *p = iov->iov_base; 1359 u32 n; 1360 int error = -EACCES; 1361 1362 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 1363 /* RFC-1014 says that the representation of XDR data must be a 1364 * multiple of four bytes 1365 * - if it isn't pointer subtraction in the NFS client may give 1366 * undefined results 1367 */ 1368 dprintk("RPC: %5u %s: XDR representation not a multiple of" 1369 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__, 1370 task->tk_rqstp->rq_rcv_buf.len); 1371 goto out_eio; 1372 } 1373 if ((len -= 3) < 0) 1374 goto out_overflow; 1375 p += 1; /* skip XID */ 1376 1377 if ((n = ntohl(*p++)) != RPC_REPLY) { 1378 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 1379 task->tk_pid, __FUNCTION__, n); 1380 goto out_garbage; 1381 } 1382 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1383 if (--len < 0) 1384 goto out_overflow; 1385 switch ((n = ntohl(*p++))) { 1386 case RPC_AUTH_ERROR: 1387 break; 1388 case RPC_MISMATCH: 1389 dprintk("RPC: %5u %s: RPC call version " 1390 "mismatch!\n", 1391 task->tk_pid, __FUNCTION__); 1392 error = -EPROTONOSUPPORT; 1393 goto out_err; 1394 default: 1395 dprintk("RPC: %5u %s: RPC call rejected, " 1396 "unknown error: %x\n", 1397 task->tk_pid, __FUNCTION__, n); 1398 goto out_eio; 1399 } 1400 if (--len < 0) 1401 goto out_overflow; 1402 switch ((n = ntohl(*p++))) { 1403 case RPC_AUTH_REJECTEDCRED: 1404 case RPC_AUTH_REJECTEDVERF: 1405 case RPCSEC_GSS_CREDPROBLEM: 1406 case RPCSEC_GSS_CTXPROBLEM: 1407 if (!task->tk_cred_retry) 1408 break; 1409 task->tk_cred_retry--; 1410 dprintk("RPC: %5u %s: retry stale creds\n", 1411 task->tk_pid, __FUNCTION__); 1412 rpcauth_invalcred(task); 1413 /* Ensure we obtain a new XID! */ 1414 xprt_release(task); 1415 task->tk_action = call_refresh; 1416 goto out_retry; 1417 case RPC_AUTH_BADCRED: 1418 case RPC_AUTH_BADVERF: 1419 /* possibly garbled cred/verf? */ 1420 if (!task->tk_garb_retry) 1421 break; 1422 task->tk_garb_retry--; 1423 dprintk("RPC: %5u %s: retry garbled creds\n", 1424 task->tk_pid, __FUNCTION__); 1425 task->tk_action = call_bind; 1426 goto out_retry; 1427 case RPC_AUTH_TOOWEAK: 1428 printk(KERN_NOTICE "call_verify: server %s requires stronger " 1429 "authentication.\n", task->tk_client->cl_server); 1430 break; 1431 default: 1432 dprintk("RPC: %5u %s: unknown auth error: %x\n", 1433 task->tk_pid, __FUNCTION__, n); 1434 error = -EIO; 1435 } 1436 dprintk("RPC: %5u %s: call rejected %d\n", 1437 task->tk_pid, __FUNCTION__, n); 1438 goto out_err; 1439 } 1440 if (!(p = rpcauth_checkverf(task, p))) { 1441 dprintk("RPC: %5u %s: auth check failed\n", 1442 task->tk_pid, __FUNCTION__); 1443 goto out_garbage; /* bad verifier, retry */ 1444 } 1445 len = p - (__be32 *)iov->iov_base - 1; 1446 if (len < 0) 1447 goto out_overflow; 1448 switch ((n = ntohl(*p++))) { 1449 case RPC_SUCCESS: 1450 return p; 1451 case RPC_PROG_UNAVAIL: 1452 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", 1453 task->tk_pid, __FUNCTION__, 1454 (unsigned int)task->tk_client->cl_prog, 1455 task->tk_client->cl_server); 1456 error = -EPFNOSUPPORT; 1457 goto out_err; 1458 case RPC_PROG_MISMATCH: 1459 dprintk("RPC: %5u %s: program %u, version %u unsupported by " 1460 "server %s\n", task->tk_pid, __FUNCTION__, 1461 (unsigned int)task->tk_client->cl_prog, 1462 (unsigned int)task->tk_client->cl_vers, 1463 task->tk_client->cl_server); 1464 error = -EPROTONOSUPPORT; 1465 goto out_err; 1466 case RPC_PROC_UNAVAIL: 1467 dprintk("RPC: %5u %s: proc %p unsupported by program %u, " 1468 "version %u on server %s\n", 1469 task->tk_pid, __FUNCTION__, 1470 task->tk_msg.rpc_proc, 1471 task->tk_client->cl_prog, 1472 task->tk_client->cl_vers, 1473 task->tk_client->cl_server); 1474 error = -EOPNOTSUPP; 1475 goto out_err; 1476 case RPC_GARBAGE_ARGS: 1477 dprintk("RPC: %5u %s: server saw garbage\n", 1478 task->tk_pid, __FUNCTION__); 1479 break; /* retry */ 1480 default: 1481 dprintk("RPC: %5u %s: server accept status: %x\n", 1482 task->tk_pid, __FUNCTION__, n); 1483 /* Also retry */ 1484 } 1485 1486out_garbage: 1487 task->tk_client->cl_stats->rpcgarbage++; 1488 if (task->tk_garb_retry) { 1489 task->tk_garb_retry--; 1490 dprintk("RPC: %5u %s: retrying\n", 1491 task->tk_pid, __FUNCTION__); 1492 task->tk_action = call_bind; 1493out_retry: 1494 return ERR_PTR(-EAGAIN); 1495 } 1496out_eio: 1497 error = -EIO; 1498out_err: 1499 rpc_exit(task, error); 1500 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 1501 __FUNCTION__, error); 1502 return ERR_PTR(error); 1503out_overflow: 1504 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 1505 __FUNCTION__); 1506 goto out_garbage; 1507} 1508 1509static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj) 1510{ 1511 return 0; 1512} 1513 1514static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj) 1515{ 1516 return 0; 1517} 1518 1519static struct rpc_procinfo rpcproc_null = { 1520 .p_encode = rpcproc_encode_null, 1521 .p_decode = rpcproc_decode_null, 1522}; 1523 1524static int rpc_ping(struct rpc_clnt *clnt, int flags) 1525{ 1526 struct rpc_message msg = { 1527 .rpc_proc = &rpcproc_null, 1528 }; 1529 int err; 1530 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1531 err = rpc_call_sync(clnt, &msg, flags); 1532 put_rpccred(msg.rpc_cred); 1533 return err; 1534} 1535 1536struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 1537{ 1538 struct rpc_message msg = { 1539 .rpc_proc = &rpcproc_null, 1540 .rpc_cred = cred, 1541 }; 1542 struct rpc_task_setup task_setup_data = { 1543 .rpc_client = clnt, 1544 .rpc_message = &msg, 1545 .callback_ops = &rpc_default_ops, 1546 .flags = flags, 1547 }; 1548 return rpc_run_task(&task_setup_data); 1549} 1550EXPORT_SYMBOL_GPL(rpc_call_null); 1551 1552#ifdef RPC_DEBUG 1553void rpc_show_tasks(void) 1554{ 1555 struct rpc_clnt *clnt; 1556 struct rpc_task *t; 1557 1558 spin_lock(&rpc_client_lock); 1559 if (list_empty(&all_clients)) 1560 goto out; 1561 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout " 1562 "-rpcwait -action- ---ops--\n"); 1563 list_for_each_entry(clnt, &all_clients, cl_clients) { 1564 if (list_empty(&clnt->cl_tasks)) 1565 continue; 1566 spin_lock(&clnt->cl_lock); 1567 list_for_each_entry(t, &clnt->cl_tasks, tk_task) { 1568 const char *rpc_waitq = "none"; 1569 int proc; 1570 1571 if (t->tk_msg.rpc_proc) 1572 proc = t->tk_msg.rpc_proc->p_proc; 1573 else 1574 proc = -1; 1575 1576 if (RPC_IS_QUEUED(t)) 1577 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq); 1578 1579 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n", 1580 t->tk_pid, proc, 1581 t->tk_flags, t->tk_status, 1582 t->tk_client, 1583 (t->tk_client ? t->tk_client->cl_prog : 0), 1584 t->tk_rqstp, t->tk_timeout, 1585 rpc_waitq, 1586 t->tk_action, t->tk_ops); 1587 } 1588 spin_unlock(&clnt->cl_lock); 1589 } 1590out: 1591 spin_unlock(&rpc_client_lock); 1592} 1593#endif 1594