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 __func__, t->tk_status) 47 48 /* 49 * All RPC clients are linked into this list 50 */ 51 static LIST_HEAD(all_clients); 52 static DEFINE_SPINLOCK(rpc_client_lock); 53 54 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 55 56 57 static void call_start(struct rpc_task *task); 58 static void call_reserve(struct rpc_task *task); 59 static void call_reserveresult(struct rpc_task *task); 60 static void call_allocate(struct rpc_task *task); 61 static void call_encode(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 static __be32 * call_header(struct rpc_task *task); 74 static __be32 * call_verify(struct rpc_task *task); 75 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 = 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); 200 201 kref_init(&clnt->cl_kref); 202 203 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 204 if (err < 0) 205 goto out_no_path; 206 207 auth = rpcauth_create(args->authflavor, clnt); 208 if (IS_ERR(auth)) { 209 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 210 args->authflavor); 211 err = PTR_ERR(auth); 212 goto out_no_auth; 213 } 214 215 /* save the nodename */ 216 clnt->cl_nodelen = strlen(utsname()->nodename); 217 if (clnt->cl_nodelen > UNX_MAXNODENAME) 218 clnt->cl_nodelen = UNX_MAXNODENAME; 219 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen); 220 rpc_register_client(clnt); 221 return clnt; 222 223 out_no_auth: 224 if (!IS_ERR(clnt->cl_dentry)) { 225 rpc_rmdir(clnt->cl_dentry); 226 rpc_put_mount(); 227 } 228 out_no_path: 229 rpc_free_iostats(clnt->cl_metrics); 230 out_no_stats: 231 if (clnt->cl_server != clnt->cl_inline_name) 232 kfree(clnt->cl_server); 233 kfree(clnt); 234 out_err: 235 xprt_put(xprt); 236 out_no_xprt: 237 rpciod_down(); 238 out_no_rpciod: 239 return ERR_PTR(err); 240 } 241 242 /* 243 * rpc_create - create an RPC client and transport with one call 244 * @args: rpc_clnt create argument structure 245 * 246 * Creates and initializes an RPC transport and an RPC client. 247 * 248 * It can ping the server in order to determine if it is up, and to see if 249 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 250 * this behavior so asynchronous tasks can also use rpc_create. 251 */ 252 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 253 { 254 struct rpc_xprt *xprt; 255 struct rpc_clnt *clnt; 256 struct xprt_create xprtargs = { 257 .ident = args->protocol, 258 .srcaddr = args->saddress, 259 .dstaddr = args->address, 260 .addrlen = args->addrsize, 261 }; 262 char servername[48]; 263 264 /* 265 * If the caller chooses not to specify a hostname, whip 266 * up a string representation of the passed-in address. 267 */ 268 if (args->servername == NULL) { 269 servername[0] = '\0'; 270 switch (args->address->sa_family) { 271 case AF_INET: { 272 struct sockaddr_in *sin = 273 (struct sockaddr_in *)args->address; 274 snprintf(servername, sizeof(servername), NIPQUAD_FMT, 275 NIPQUAD(sin->sin_addr.s_addr)); 276 break; 277 } 278 case AF_INET6: { 279 struct sockaddr_in6 *sin = 280 (struct sockaddr_in6 *)args->address; 281 snprintf(servername, sizeof(servername), NIP6_FMT, 282 NIP6(sin->sin6_addr)); 283 break; 284 } 285 default: 286 /* caller wants default server name, but 287 * address family isn't recognized. */ 288 return ERR_PTR(-EINVAL); 289 } 290 args->servername = servername; 291 } 292 293 xprt = xprt_create_transport(&xprtargs); 294 if (IS_ERR(xprt)) 295 return (struct rpc_clnt *)xprt; 296 297 /* 298 * By default, kernel RPC client connects from a reserved port. 299 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 300 * but it is always enabled for rpciod, which handles the connect 301 * operation. 302 */ 303 xprt->resvport = 1; 304 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 305 xprt->resvport = 0; 306 307 clnt = rpc_new_client(args, xprt); 308 if (IS_ERR(clnt)) 309 return clnt; 310 311 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 312 int err = rpc_ping(clnt, RPC_TASK_SOFT); 313 if (err != 0) { 314 rpc_shutdown_client(clnt); 315 return ERR_PTR(err); 316 } 317 } 318 319 clnt->cl_softrtry = 1; 320 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 321 clnt->cl_softrtry = 0; 322 323 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 } 330 EXPORT_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 */ 337 struct rpc_clnt * 338 rpc_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_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; 366 out_no_path: 367 rpc_free_iostats(new->cl_metrics); 368 out_no_stats: 369 kfree(new); 370 out_no_clnt: 371 dprintk("RPC: %s: returned error %d\n", __func__, err); 372 return ERR_PTR(err); 373 } 374 EXPORT_SYMBOL_GPL(rpc_clone_client); 375 376 /* 377 * Properly shut down an RPC client, terminating all outstanding 378 * requests. 379 */ 380 void 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 } 393 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 394 395 /* 396 * Free an RPC client 397 */ 398 static void 399 rpc_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); 415 out_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 */ 427 static void 428 rpc_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 */ 451 void 452 rpc_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 */ 471 struct 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); 491 if (err != 0) { 492 rpc_shutdown_client(clnt); 493 clnt = ERR_PTR(err); 494 } 495 out: 496 return clnt; 497 } 498 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 499 500 /* 501 * Default callback for async RPC calls 502 */ 503 static void 504 rpc_default_callback(struct rpc_task *task, void *data) 505 { 506 } 507 508 static const struct rpc_call_ops rpc_default_ops = { 509 .rpc_call_done = rpc_default_callback, 510 }; 511 512 /** 513 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 514 * @task_setup_data: pointer to task initialisation data 515 */ 516 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 517 { 518 struct rpc_task *task, *ret; 519 520 task = rpc_new_task(task_setup_data); 521 if (task == NULL) { 522 rpc_release_calldata(task_setup_data->callback_ops, 523 task_setup_data->callback_data); 524 ret = ERR_PTR(-ENOMEM); 525 goto out; 526 } 527 528 if (task->tk_status != 0) { 529 ret = ERR_PTR(task->tk_status); 530 rpc_put_task(task); 531 goto out; 532 } 533 atomic_inc(&task->tk_count); 534 rpc_execute(task); 535 ret = task; 536 out: 537 return ret; 538 } 539 EXPORT_SYMBOL_GPL(rpc_run_task); 540 541 /** 542 * rpc_call_sync - Perform a synchronous RPC call 543 * @clnt: pointer to RPC client 544 * @msg: RPC call parameters 545 * @flags: RPC call flags 546 */ 547 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 548 { 549 struct rpc_task *task; 550 struct rpc_task_setup task_setup_data = { 551 .rpc_client = clnt, 552 .rpc_message = msg, 553 .callback_ops = &rpc_default_ops, 554 .flags = flags, 555 }; 556 int status; 557 558 BUG_ON(flags & RPC_TASK_ASYNC); 559 560 task = rpc_run_task(&task_setup_data); 561 if (IS_ERR(task)) 562 return PTR_ERR(task); 563 status = task->tk_status; 564 rpc_put_task(task); 565 return status; 566 } 567 EXPORT_SYMBOL_GPL(rpc_call_sync); 568 569 /** 570 * rpc_call_async - Perform an asynchronous RPC call 571 * @clnt: pointer to RPC client 572 * @msg: RPC call parameters 573 * @flags: RPC call flags 574 * @tk_ops: RPC call ops 575 * @data: user call data 576 */ 577 int 578 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 579 const struct rpc_call_ops *tk_ops, void *data) 580 { 581 struct rpc_task *task; 582 struct rpc_task_setup task_setup_data = { 583 .rpc_client = clnt, 584 .rpc_message = msg, 585 .callback_ops = tk_ops, 586 .callback_data = data, 587 .flags = flags|RPC_TASK_ASYNC, 588 }; 589 590 task = rpc_run_task(&task_setup_data); 591 if (IS_ERR(task)) 592 return PTR_ERR(task); 593 rpc_put_task(task); 594 return 0; 595 } 596 EXPORT_SYMBOL_GPL(rpc_call_async); 597 598 void 599 rpc_call_start(struct rpc_task *task) 600 { 601 task->tk_action = call_start; 602 } 603 EXPORT_SYMBOL_GPL(rpc_call_start); 604 605 /** 606 * rpc_peeraddr - extract remote peer address from clnt's xprt 607 * @clnt: RPC client structure 608 * @buf: target buffer 609 * @bufsize: length of target buffer 610 * 611 * Returns the number of bytes that are actually in the stored address. 612 */ 613 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 614 { 615 size_t bytes; 616 struct rpc_xprt *xprt = clnt->cl_xprt; 617 618 bytes = sizeof(xprt->addr); 619 if (bytes > bufsize) 620 bytes = bufsize; 621 memcpy(buf, &clnt->cl_xprt->addr, bytes); 622 return xprt->addrlen; 623 } 624 EXPORT_SYMBOL_GPL(rpc_peeraddr); 625 626 /** 627 * rpc_peeraddr2str - return remote peer address in printable format 628 * @clnt: RPC client structure 629 * @format: address format 630 * 631 */ 632 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 633 enum rpc_display_format_t format) 634 { 635 struct rpc_xprt *xprt = clnt->cl_xprt; 636 637 if (xprt->address_strings[format] != NULL) 638 return xprt->address_strings[format]; 639 else 640 return "unprintable"; 641 } 642 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 643 644 void 645 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 646 { 647 struct rpc_xprt *xprt = clnt->cl_xprt; 648 if (xprt->ops->set_buffer_size) 649 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 650 } 651 EXPORT_SYMBOL_GPL(rpc_setbufsize); 652 653 /* 654 * Return size of largest payload RPC client can support, in bytes 655 * 656 * For stream transports, this is one RPC record fragment (see RFC 657 * 1831), as we don't support multi-record requests yet. For datagram 658 * transports, this is the size of an IP packet minus the IP, UDP, and 659 * RPC header sizes. 660 */ 661 size_t rpc_max_payload(struct rpc_clnt *clnt) 662 { 663 return clnt->cl_xprt->max_payload; 664 } 665 EXPORT_SYMBOL_GPL(rpc_max_payload); 666 667 /** 668 * rpc_force_rebind - force transport to check that remote port is unchanged 669 * @clnt: client to rebind 670 * 671 */ 672 void rpc_force_rebind(struct rpc_clnt *clnt) 673 { 674 if (clnt->cl_autobind) 675 xprt_clear_bound(clnt->cl_xprt); 676 } 677 EXPORT_SYMBOL_GPL(rpc_force_rebind); 678 679 /* 680 * Restart an (async) RPC call. Usually called from within the 681 * exit handler. 682 */ 683 void 684 rpc_restart_call(struct rpc_task *task) 685 { 686 if (RPC_ASSASSINATED(task)) 687 return; 688 689 task->tk_action = call_start; 690 } 691 EXPORT_SYMBOL_GPL(rpc_restart_call); 692 693 /* 694 * 0. Initial state 695 * 696 * Other FSM states can be visited zero or more times, but 697 * this state is visited exactly once for each RPC. 698 */ 699 static void 700 call_start(struct rpc_task *task) 701 { 702 struct rpc_clnt *clnt = task->tk_client; 703 704 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid, 705 clnt->cl_protname, clnt->cl_vers, 706 task->tk_msg.rpc_proc->p_proc, 707 (RPC_IS_ASYNC(task) ? "async" : "sync")); 708 709 /* Increment call count */ 710 task->tk_msg.rpc_proc->p_count++; 711 clnt->cl_stats->rpccnt++; 712 task->tk_action = call_reserve; 713 } 714 715 /* 716 * 1. Reserve an RPC call slot 717 */ 718 static void 719 call_reserve(struct rpc_task *task) 720 { 721 dprint_status(task); 722 723 if (!rpcauth_uptodatecred(task)) { 724 task->tk_action = call_refresh; 725 return; 726 } 727 728 task->tk_status = 0; 729 task->tk_action = call_reserveresult; 730 xprt_reserve(task); 731 } 732 733 /* 734 * 1b. Grok the result of xprt_reserve() 735 */ 736 static void 737 call_reserveresult(struct rpc_task *task) 738 { 739 int status = task->tk_status; 740 741 dprint_status(task); 742 743 /* 744 * After a call to xprt_reserve(), we must have either 745 * a request slot or else an error status. 746 */ 747 task->tk_status = 0; 748 if (status >= 0) { 749 if (task->tk_rqstp) { 750 task->tk_action = call_allocate; 751 return; 752 } 753 754 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 755 __func__, status); 756 rpc_exit(task, -EIO); 757 return; 758 } 759 760 /* 761 * Even though there was an error, we may have acquired 762 * a request slot somehow. Make sure not to leak it. 763 */ 764 if (task->tk_rqstp) { 765 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 766 __func__, status); 767 xprt_release(task); 768 } 769 770 switch (status) { 771 case -EAGAIN: /* woken up; retry */ 772 task->tk_action = call_reserve; 773 return; 774 case -EIO: /* probably a shutdown */ 775 break; 776 default: 777 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 778 __func__, status); 779 break; 780 } 781 rpc_exit(task, status); 782 } 783 784 /* 785 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 786 * (Note: buffer memory is freed in xprt_release). 787 */ 788 static void 789 call_allocate(struct rpc_task *task) 790 { 791 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack; 792 struct rpc_rqst *req = task->tk_rqstp; 793 struct rpc_xprt *xprt = task->tk_xprt; 794 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 795 796 dprint_status(task); 797 798 task->tk_status = 0; 799 task->tk_action = call_bind; 800 801 if (req->rq_buffer) 802 return; 803 804 if (proc->p_proc != 0) { 805 BUG_ON(proc->p_arglen == 0); 806 if (proc->p_decode != NULL) 807 BUG_ON(proc->p_replen == 0); 808 } 809 810 /* 811 * Calculate the size (in quads) of the RPC call 812 * and reply headers, and convert both values 813 * to byte sizes. 814 */ 815 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 816 req->rq_callsize <<= 2; 817 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 818 req->rq_rcvsize <<= 2; 819 820 req->rq_buffer = xprt->ops->buf_alloc(task, 821 req->rq_callsize + req->rq_rcvsize); 822 if (req->rq_buffer != NULL) 823 return; 824 825 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 826 827 if (RPC_IS_ASYNC(task) || !signalled()) { 828 task->tk_action = call_allocate; 829 rpc_delay(task, HZ>>4); 830 return; 831 } 832 833 rpc_exit(task, -ERESTARTSYS); 834 } 835 836 static inline int 837 rpc_task_need_encode(struct rpc_task *task) 838 { 839 return task->tk_rqstp->rq_snd_buf.len == 0; 840 } 841 842 static inline void 843 rpc_task_force_reencode(struct rpc_task *task) 844 { 845 task->tk_rqstp->rq_snd_buf.len = 0; 846 } 847 848 static inline void 849 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 850 { 851 buf->head[0].iov_base = start; 852 buf->head[0].iov_len = len; 853 buf->tail[0].iov_len = 0; 854 buf->page_len = 0; 855 buf->flags = 0; 856 buf->len = 0; 857 buf->buflen = len; 858 } 859 860 /* 861 * 3. Encode arguments of an RPC call 862 */ 863 static void 864 call_encode(struct rpc_task *task) 865 { 866 struct rpc_rqst *req = task->tk_rqstp; 867 kxdrproc_t encode; 868 __be32 *p; 869 870 dprint_status(task); 871 872 rpc_xdr_buf_init(&req->rq_snd_buf, 873 req->rq_buffer, 874 req->rq_callsize); 875 rpc_xdr_buf_init(&req->rq_rcv_buf, 876 (char *)req->rq_buffer + req->rq_callsize, 877 req->rq_rcvsize); 878 879 /* Encode header and provided arguments */ 880 encode = task->tk_msg.rpc_proc->p_encode; 881 if (!(p = call_header(task))) { 882 printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); 883 rpc_exit(task, -EIO); 884 return; 885 } 886 if (encode == NULL) 887 return; 888 889 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 890 task->tk_msg.rpc_argp); 891 if (task->tk_status == -ENOMEM) { 892 /* XXX: Is this sane? */ 893 rpc_delay(task, 3*HZ); 894 task->tk_status = -EAGAIN; 895 } 896 } 897 898 /* 899 * 4. Get the server port number if not yet set 900 */ 901 static void 902 call_bind(struct rpc_task *task) 903 { 904 struct rpc_xprt *xprt = task->tk_xprt; 905 906 dprint_status(task); 907 908 task->tk_action = call_connect; 909 if (!xprt_bound(xprt)) { 910 task->tk_action = call_bind_status; 911 task->tk_timeout = xprt->bind_timeout; 912 xprt->ops->rpcbind(task); 913 } 914 } 915 916 /* 917 * 4a. Sort out bind result 918 */ 919 static void 920 call_bind_status(struct rpc_task *task) 921 { 922 int status = -EIO; 923 924 if (task->tk_status >= 0) { 925 dprint_status(task); 926 task->tk_status = 0; 927 task->tk_action = call_connect; 928 return; 929 } 930 931 switch (task->tk_status) { 932 case -EAGAIN: 933 dprintk("RPC: %5u rpcbind waiting for another request " 934 "to finish\n", task->tk_pid); 935 /* avoid busy-waiting here -- could be a network outage. */ 936 rpc_delay(task, 5*HZ); 937 goto retry_timeout; 938 case -EACCES: 939 dprintk("RPC: %5u remote rpcbind: RPC program/version " 940 "unavailable\n", task->tk_pid); 941 /* fail immediately if this is an RPC ping */ 942 if (task->tk_msg.rpc_proc->p_proc == 0) { 943 status = -EOPNOTSUPP; 944 break; 945 } 946 rpc_delay(task, 3*HZ); 947 goto retry_timeout; 948 case -ETIMEDOUT: 949 dprintk("RPC: %5u rpcbind request timed out\n", 950 task->tk_pid); 951 goto retry_timeout; 952 case -EPFNOSUPPORT: 953 /* server doesn't support any rpcbind version we know of */ 954 dprintk("RPC: %5u remote rpcbind service unavailable\n", 955 task->tk_pid); 956 break; 957 case -EPROTONOSUPPORT: 958 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 959 task->tk_pid); 960 task->tk_status = 0; 961 task->tk_action = call_bind; 962 return; 963 default: 964 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 965 task->tk_pid, -task->tk_status); 966 } 967 968 rpc_exit(task, status); 969 return; 970 971 retry_timeout: 972 task->tk_action = call_timeout; 973 } 974 975 /* 976 * 4b. Connect to the RPC server 977 */ 978 static void 979 call_connect(struct rpc_task *task) 980 { 981 struct rpc_xprt *xprt = task->tk_xprt; 982 983 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 984 task->tk_pid, xprt, 985 (xprt_connected(xprt) ? "is" : "is not")); 986 987 task->tk_action = call_transmit; 988 if (!xprt_connected(xprt)) { 989 task->tk_action = call_connect_status; 990 if (task->tk_status < 0) 991 return; 992 xprt_connect(task); 993 } 994 } 995 996 /* 997 * 4c. Sort out connect result 998 */ 999 static void 1000 call_connect_status(struct rpc_task *task) 1001 { 1002 struct rpc_clnt *clnt = task->tk_client; 1003 int status = task->tk_status; 1004 1005 dprint_status(task); 1006 1007 task->tk_status = 0; 1008 if (status >= 0) { 1009 clnt->cl_stats->netreconn++; 1010 task->tk_action = call_transmit; 1011 return; 1012 } 1013 1014 /* Something failed: remote service port may have changed */ 1015 rpc_force_rebind(clnt); 1016 1017 switch (status) { 1018 case -ENOTCONN: 1019 case -EAGAIN: 1020 task->tk_action = call_bind; 1021 if (!RPC_IS_SOFT(task)) 1022 return; 1023 /* if soft mounted, test if we've timed out */ 1024 case -ETIMEDOUT: 1025 task->tk_action = call_timeout; 1026 return; 1027 } 1028 rpc_exit(task, -EIO); 1029 } 1030 1031 /* 1032 * 5. Transmit the RPC request, and wait for reply 1033 */ 1034 static void 1035 call_transmit(struct rpc_task *task) 1036 { 1037 dprint_status(task); 1038 1039 task->tk_action = call_status; 1040 if (task->tk_status < 0) 1041 return; 1042 task->tk_status = xprt_prepare_transmit(task); 1043 if (task->tk_status != 0) 1044 return; 1045 task->tk_action = call_transmit_status; 1046 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1047 if (rpc_task_need_encode(task)) { 1048 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0); 1049 call_encode(task); 1050 /* Did the encode result in an error condition? */ 1051 if (task->tk_status != 0) 1052 return; 1053 } 1054 xprt_transmit(task); 1055 if (task->tk_status < 0) 1056 return; 1057 /* 1058 * On success, ensure that we call xprt_end_transmit() before sleeping 1059 * in order to allow access to the socket to other RPC requests. 1060 */ 1061 call_transmit_status(task); 1062 if (task->tk_msg.rpc_proc->p_decode != NULL) 1063 return; 1064 task->tk_action = rpc_exit_task; 1065 rpc_wake_up_queued_task(&task->tk_xprt->pending, task); 1066 } 1067 1068 /* 1069 * 5a. Handle cleanup after a transmission 1070 */ 1071 static void 1072 call_transmit_status(struct rpc_task *task) 1073 { 1074 task->tk_action = call_status; 1075 /* 1076 * Special case: if we've been waiting on the socket's write_space() 1077 * callback, then don't call xprt_end_transmit(). 1078 */ 1079 if (task->tk_status == -EAGAIN) 1080 return; 1081 xprt_end_transmit(task); 1082 rpc_task_force_reencode(task); 1083 } 1084 1085 /* 1086 * 6. Sort out the RPC call status 1087 */ 1088 static void 1089 call_status(struct rpc_task *task) 1090 { 1091 struct rpc_clnt *clnt = task->tk_client; 1092 struct rpc_rqst *req = task->tk_rqstp; 1093 int status; 1094 1095 if (req->rq_received > 0 && !req->rq_bytes_sent) 1096 task->tk_status = req->rq_received; 1097 1098 dprint_status(task); 1099 1100 status = task->tk_status; 1101 if (status >= 0) { 1102 task->tk_action = call_decode; 1103 return; 1104 } 1105 1106 task->tk_status = 0; 1107 switch(status) { 1108 case -EHOSTDOWN: 1109 case -EHOSTUNREACH: 1110 case -ENETUNREACH: 1111 /* 1112 * Delay any retries for 3 seconds, then handle as if it 1113 * were a timeout. 1114 */ 1115 rpc_delay(task, 3*HZ); 1116 case -ETIMEDOUT: 1117 task->tk_action = call_timeout; 1118 if (task->tk_client->cl_discrtry) 1119 xprt_conditional_disconnect(task->tk_xprt, 1120 req->rq_connect_cookie); 1121 break; 1122 case -ECONNREFUSED: 1123 case -ENOTCONN: 1124 rpc_force_rebind(clnt); 1125 task->tk_action = call_bind; 1126 break; 1127 case -EAGAIN: 1128 task->tk_action = call_transmit; 1129 break; 1130 case -EIO: 1131 /* shutdown or soft timeout */ 1132 rpc_exit(task, status); 1133 break; 1134 default: 1135 printk("%s: RPC call returned error %d\n", 1136 clnt->cl_protname, -status); 1137 rpc_exit(task, status); 1138 } 1139 } 1140 1141 /* 1142 * 6a. Handle RPC timeout 1143 * We do not release the request slot, so we keep using the 1144 * same XID for all retransmits. 1145 */ 1146 static void 1147 call_timeout(struct rpc_task *task) 1148 { 1149 struct rpc_clnt *clnt = task->tk_client; 1150 1151 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 1152 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 1153 goto retry; 1154 } 1155 1156 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 1157 task->tk_timeouts++; 1158 1159 if (RPC_IS_SOFT(task)) { 1160 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 1161 clnt->cl_protname, clnt->cl_server); 1162 rpc_exit(task, -EIO); 1163 return; 1164 } 1165 1166 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 1167 task->tk_flags |= RPC_CALL_MAJORSEEN; 1168 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 1169 clnt->cl_protname, clnt->cl_server); 1170 } 1171 rpc_force_rebind(clnt); 1172 /* 1173 * Did our request time out due to an RPCSEC_GSS out-of-sequence 1174 * event? RFC2203 requires the server to drop all such requests. 1175 */ 1176 rpcauth_invalcred(task); 1177 1178 retry: 1179 clnt->cl_stats->rpcretrans++; 1180 task->tk_action = call_bind; 1181 task->tk_status = 0; 1182 } 1183 1184 /* 1185 * 7. Decode the RPC reply 1186 */ 1187 static void 1188 call_decode(struct rpc_task *task) 1189 { 1190 struct rpc_clnt *clnt = task->tk_client; 1191 struct rpc_rqst *req = task->tk_rqstp; 1192 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 1193 __be32 *p; 1194 1195 dprintk("RPC: %5u call_decode (status %d)\n", 1196 task->tk_pid, task->tk_status); 1197 1198 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 1199 printk(KERN_NOTICE "%s: server %s OK\n", 1200 clnt->cl_protname, clnt->cl_server); 1201 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 1202 } 1203 1204 /* 1205 * Ensure that we see all writes made by xprt_complete_rqst() 1206 * before it changed req->rq_received. 1207 */ 1208 smp_rmb(); 1209 req->rq_rcv_buf.len = req->rq_private_buf.len; 1210 1211 /* Check that the softirq receive buffer is valid */ 1212 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1213 sizeof(req->rq_rcv_buf)) != 0); 1214 1215 if (req->rq_rcv_buf.len < 12) { 1216 if (!RPC_IS_SOFT(task)) { 1217 task->tk_action = call_bind; 1218 clnt->cl_stats->rpcretrans++; 1219 goto out_retry; 1220 } 1221 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 1222 clnt->cl_protname, task->tk_status); 1223 task->tk_action = call_timeout; 1224 goto out_retry; 1225 } 1226 1227 /* Verify the RPC header */ 1228 p = call_verify(task); 1229 if (IS_ERR(p)) { 1230 if (p == ERR_PTR(-EAGAIN)) 1231 goto out_retry; 1232 return; 1233 } 1234 1235 task->tk_action = rpc_exit_task; 1236 1237 if (decode) { 1238 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1239 task->tk_msg.rpc_resp); 1240 } 1241 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 1242 task->tk_status); 1243 return; 1244 out_retry: 1245 task->tk_status = 0; 1246 /* Note: call_verify() may have freed the RPC slot */ 1247 if (task->tk_rqstp == req) { 1248 req->rq_received = req->rq_rcv_buf.len = 0; 1249 if (task->tk_client->cl_discrtry) 1250 xprt_conditional_disconnect(task->tk_xprt, 1251 req->rq_connect_cookie); 1252 } 1253 } 1254 1255 /* 1256 * 8. Refresh the credentials if rejected by the server 1257 */ 1258 static void 1259 call_refresh(struct rpc_task *task) 1260 { 1261 dprint_status(task); 1262 1263 task->tk_action = call_refreshresult; 1264 task->tk_status = 0; 1265 task->tk_client->cl_stats->rpcauthrefresh++; 1266 rpcauth_refreshcred(task); 1267 } 1268 1269 /* 1270 * 8a. Process the results of a credential refresh 1271 */ 1272 static void 1273 call_refreshresult(struct rpc_task *task) 1274 { 1275 int status = task->tk_status; 1276 1277 dprint_status(task); 1278 1279 task->tk_status = 0; 1280 task->tk_action = call_reserve; 1281 if (status >= 0 && rpcauth_uptodatecred(task)) 1282 return; 1283 if (status == -EACCES) { 1284 rpc_exit(task, -EACCES); 1285 return; 1286 } 1287 task->tk_action = call_refresh; 1288 if (status != -ETIMEDOUT) 1289 rpc_delay(task, 3*HZ); 1290 return; 1291 } 1292 1293 /* 1294 * Call header serialization 1295 */ 1296 static __be32 * 1297 call_header(struct rpc_task *task) 1298 { 1299 struct rpc_clnt *clnt = task->tk_client; 1300 struct rpc_rqst *req = task->tk_rqstp; 1301 __be32 *p = req->rq_svec[0].iov_base; 1302 1303 /* FIXME: check buffer size? */ 1304 1305 p = xprt_skip_transport_header(task->tk_xprt, p); 1306 *p++ = req->rq_xid; /* XID */ 1307 *p++ = htonl(RPC_CALL); /* CALL */ 1308 *p++ = htonl(RPC_VERSION); /* RPC version */ 1309 *p++ = htonl(clnt->cl_prog); /* program number */ 1310 *p++ = htonl(clnt->cl_vers); /* program version */ 1311 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1312 p = rpcauth_marshcred(task, p); 1313 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1314 return p; 1315 } 1316 1317 /* 1318 * Reply header verification 1319 */ 1320 static __be32 * 1321 call_verify(struct rpc_task *task) 1322 { 1323 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1324 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1325 __be32 *p = iov->iov_base; 1326 u32 n; 1327 int error = -EACCES; 1328 1329 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 1330 /* RFC-1014 says that the representation of XDR data must be a 1331 * multiple of four bytes 1332 * - if it isn't pointer subtraction in the NFS client may give 1333 * undefined results 1334 */ 1335 dprintk("RPC: %5u %s: XDR representation not a multiple of" 1336 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 1337 task->tk_rqstp->rq_rcv_buf.len); 1338 goto out_eio; 1339 } 1340 if ((len -= 3) < 0) 1341 goto out_overflow; 1342 p += 1; /* skip XID */ 1343 1344 if ((n = ntohl(*p++)) != RPC_REPLY) { 1345 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 1346 task->tk_pid, __func__, n); 1347 goto out_garbage; 1348 } 1349 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1350 if (--len < 0) 1351 goto out_overflow; 1352 switch ((n = ntohl(*p++))) { 1353 case RPC_AUTH_ERROR: 1354 break; 1355 case RPC_MISMATCH: 1356 dprintk("RPC: %5u %s: RPC call version " 1357 "mismatch!\n", 1358 task->tk_pid, __func__); 1359 error = -EPROTONOSUPPORT; 1360 goto out_err; 1361 default: 1362 dprintk("RPC: %5u %s: RPC call rejected, " 1363 "unknown error: %x\n", 1364 task->tk_pid, __func__, n); 1365 goto out_eio; 1366 } 1367 if (--len < 0) 1368 goto out_overflow; 1369 switch ((n = ntohl(*p++))) { 1370 case RPC_AUTH_REJECTEDCRED: 1371 case RPC_AUTH_REJECTEDVERF: 1372 case RPCSEC_GSS_CREDPROBLEM: 1373 case RPCSEC_GSS_CTXPROBLEM: 1374 if (!task->tk_cred_retry) 1375 break; 1376 task->tk_cred_retry--; 1377 dprintk("RPC: %5u %s: retry stale creds\n", 1378 task->tk_pid, __func__); 1379 rpcauth_invalcred(task); 1380 /* Ensure we obtain a new XID! */ 1381 xprt_release(task); 1382 task->tk_action = call_refresh; 1383 goto out_retry; 1384 case RPC_AUTH_BADCRED: 1385 case RPC_AUTH_BADVERF: 1386 /* possibly garbled cred/verf? */ 1387 if (!task->tk_garb_retry) 1388 break; 1389 task->tk_garb_retry--; 1390 dprintk("RPC: %5u %s: retry garbled creds\n", 1391 task->tk_pid, __func__); 1392 task->tk_action = call_bind; 1393 goto out_retry; 1394 case RPC_AUTH_TOOWEAK: 1395 printk(KERN_NOTICE "call_verify: server %s requires stronger " 1396 "authentication.\n", task->tk_client->cl_server); 1397 break; 1398 default: 1399 dprintk("RPC: %5u %s: unknown auth error: %x\n", 1400 task->tk_pid, __func__, n); 1401 error = -EIO; 1402 } 1403 dprintk("RPC: %5u %s: call rejected %d\n", 1404 task->tk_pid, __func__, n); 1405 goto out_err; 1406 } 1407 if (!(p = rpcauth_checkverf(task, p))) { 1408 dprintk("RPC: %5u %s: auth check failed\n", 1409 task->tk_pid, __func__); 1410 goto out_garbage; /* bad verifier, retry */ 1411 } 1412 len = p - (__be32 *)iov->iov_base - 1; 1413 if (len < 0) 1414 goto out_overflow; 1415 switch ((n = ntohl(*p++))) { 1416 case RPC_SUCCESS: 1417 return p; 1418 case RPC_PROG_UNAVAIL: 1419 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n", 1420 task->tk_pid, __func__, 1421 (unsigned int)task->tk_client->cl_prog, 1422 task->tk_client->cl_server); 1423 error = -EPFNOSUPPORT; 1424 goto out_err; 1425 case RPC_PROG_MISMATCH: 1426 dprintk("RPC: %5u %s: program %u, version %u unsupported by " 1427 "server %s\n", task->tk_pid, __func__, 1428 (unsigned int)task->tk_client->cl_prog, 1429 (unsigned int)task->tk_client->cl_vers, 1430 task->tk_client->cl_server); 1431 error = -EPROTONOSUPPORT; 1432 goto out_err; 1433 case RPC_PROC_UNAVAIL: 1434 dprintk("RPC: %5u %s: proc %p unsupported by program %u, " 1435 "version %u on server %s\n", 1436 task->tk_pid, __func__, 1437 task->tk_msg.rpc_proc, 1438 task->tk_client->cl_prog, 1439 task->tk_client->cl_vers, 1440 task->tk_client->cl_server); 1441 error = -EOPNOTSUPP; 1442 goto out_err; 1443 case RPC_GARBAGE_ARGS: 1444 dprintk("RPC: %5u %s: server saw garbage\n", 1445 task->tk_pid, __func__); 1446 break; /* retry */ 1447 default: 1448 dprintk("RPC: %5u %s: server accept status: %x\n", 1449 task->tk_pid, __func__, n); 1450 /* Also retry */ 1451 } 1452 1453 out_garbage: 1454 task->tk_client->cl_stats->rpcgarbage++; 1455 if (task->tk_garb_retry) { 1456 task->tk_garb_retry--; 1457 dprintk("RPC: %5u %s: retrying\n", 1458 task->tk_pid, __func__); 1459 task->tk_action = call_bind; 1460 out_retry: 1461 return ERR_PTR(-EAGAIN); 1462 } 1463 out_eio: 1464 error = -EIO; 1465 out_err: 1466 rpc_exit(task, error); 1467 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 1468 __func__, error); 1469 return ERR_PTR(error); 1470 out_overflow: 1471 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 1472 __func__); 1473 goto out_garbage; 1474 } 1475 1476 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj) 1477 { 1478 return 0; 1479 } 1480 1481 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj) 1482 { 1483 return 0; 1484 } 1485 1486 static struct rpc_procinfo rpcproc_null = { 1487 .p_encode = rpcproc_encode_null, 1488 .p_decode = rpcproc_decode_null, 1489 }; 1490 1491 static int rpc_ping(struct rpc_clnt *clnt, int flags) 1492 { 1493 struct rpc_message msg = { 1494 .rpc_proc = &rpcproc_null, 1495 }; 1496 int err; 1497 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1498 err = rpc_call_sync(clnt, &msg, flags); 1499 put_rpccred(msg.rpc_cred); 1500 return err; 1501 } 1502 1503 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 1504 { 1505 struct rpc_message msg = { 1506 .rpc_proc = &rpcproc_null, 1507 .rpc_cred = cred, 1508 }; 1509 struct rpc_task_setup task_setup_data = { 1510 .rpc_client = clnt, 1511 .rpc_message = &msg, 1512 .callback_ops = &rpc_default_ops, 1513 .flags = flags, 1514 }; 1515 return rpc_run_task(&task_setup_data); 1516 } 1517 EXPORT_SYMBOL_GPL(rpc_call_null); 1518 1519 #ifdef RPC_DEBUG 1520 void rpc_show_tasks(void) 1521 { 1522 struct rpc_clnt *clnt; 1523 struct rpc_task *t; 1524 1525 spin_lock(&rpc_client_lock); 1526 if (list_empty(&all_clients)) 1527 goto out; 1528 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout " 1529 "-rpcwait -action- ---ops--\n"); 1530 list_for_each_entry(clnt, &all_clients, cl_clients) { 1531 if (list_empty(&clnt->cl_tasks)) 1532 continue; 1533 spin_lock(&clnt->cl_lock); 1534 list_for_each_entry(t, &clnt->cl_tasks, tk_task) { 1535 const char *rpc_waitq = "none"; 1536 int proc; 1537 1538 if (t->tk_msg.rpc_proc) 1539 proc = t->tk_msg.rpc_proc->p_proc; 1540 else 1541 proc = -1; 1542 1543 if (RPC_IS_QUEUED(t)) 1544 rpc_waitq = rpc_qname(t->tk_waitqueue); 1545 1546 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n", 1547 t->tk_pid, proc, 1548 t->tk_flags, t->tk_status, 1549 t->tk_client, 1550 (t->tk_client ? t->tk_client->cl_prog : 0), 1551 t->tk_rqstp, t->tk_timeout, 1552 rpc_waitq, 1553 t->tk_action, t->tk_ops); 1554 } 1555 spin_unlock(&clnt->cl_lock); 1556 } 1557 out: 1558 spin_unlock(&rpc_client_lock); 1559 } 1560 #endif 1561