1/* 2 * linux/net/sunrpc/clnt.c 3 * 4 * This file contains the high-level RPC interface. 5 * It is modeled as a finite state machine to support both synchronous 6 * and asynchronous requests. 7 * 8 * - RPC header generation and argument serialization. 9 * - Credential refresh. 10 * - TCP connect handling. 11 * - Retry of operation when it is suspected the operation failed because 12 * of uid squashing on the server, or when the credentials were stale 13 * and need to be refreshed, or when a packet was damaged in transit. 14 * This may be have to be moved to the VFS layer. 15 * 16 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 18 */ 19 20 21#include <linux/module.h> 22#include <linux/types.h> 23#include <linux/kallsyms.h> 24#include <linux/mm.h> 25#include <linux/namei.h> 26#include <linux/mount.h> 27#include <linux/slab.h> 28#include <linux/rcupdate.h> 29#include <linux/utsname.h> 30#include <linux/workqueue.h> 31#include <linux/in.h> 32#include <linux/in6.h> 33#include <linux/un.h> 34 35#include <linux/sunrpc/clnt.h> 36#include <linux/sunrpc/addr.h> 37#include <linux/sunrpc/rpc_pipe_fs.h> 38#include <linux/sunrpc/metrics.h> 39#include <linux/sunrpc/bc_xprt.h> 40#include <trace/events/sunrpc.h> 41 42#include "sunrpc.h" 43#include "netns.h" 44 45#ifdef RPC_DEBUG 46# define RPCDBG_FACILITY RPCDBG_CALL 47#endif 48 49#define dprint_status(t) \ 50 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 51 __func__, t->tk_status) 52 53/* 54 * All RPC clients are linked into this list 55 */ 56 57static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 58 59 60static void call_start(struct rpc_task *task); 61static void call_reserve(struct rpc_task *task); 62static void call_reserveresult(struct rpc_task *task); 63static void call_allocate(struct rpc_task *task); 64static void call_decode(struct rpc_task *task); 65static void call_bind(struct rpc_task *task); 66static void call_bind_status(struct rpc_task *task); 67static void call_transmit(struct rpc_task *task); 68#if defined(CONFIG_SUNRPC_BACKCHANNEL) 69static void call_bc_transmit(struct rpc_task *task); 70#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 71static void call_status(struct rpc_task *task); 72static void call_transmit_status(struct rpc_task *task); 73static void call_refresh(struct rpc_task *task); 74static void call_refreshresult(struct rpc_task *task); 75static void call_timeout(struct rpc_task *task); 76static void call_connect(struct rpc_task *task); 77static void call_connect_status(struct rpc_task *task); 78 79static __be32 *rpc_encode_header(struct rpc_task *task); 80static __be32 *rpc_verify_header(struct rpc_task *task); 81static int rpc_ping(struct rpc_clnt *clnt); 82 83static void rpc_register_client(struct rpc_clnt *clnt) 84{ 85 struct net *net = rpc_net_ns(clnt); 86 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 87 88 spin_lock(&sn->rpc_client_lock); 89 list_add(&clnt->cl_clients, &sn->all_clients); 90 spin_unlock(&sn->rpc_client_lock); 91} 92 93static void rpc_unregister_client(struct rpc_clnt *clnt) 94{ 95 struct net *net = rpc_net_ns(clnt); 96 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 97 98 spin_lock(&sn->rpc_client_lock); 99 list_del(&clnt->cl_clients); 100 spin_unlock(&sn->rpc_client_lock); 101} 102 103static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 104{ 105 rpc_remove_client_dir(clnt); 106} 107 108static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 109{ 110 struct net *net = rpc_net_ns(clnt); 111 struct super_block *pipefs_sb; 112 113 pipefs_sb = rpc_get_sb_net(net); 114 if (pipefs_sb) { 115 __rpc_clnt_remove_pipedir(clnt); 116 rpc_put_sb_net(net); 117 } 118} 119 120static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 121 struct rpc_clnt *clnt) 122{ 123 static uint32_t clntid; 124 const char *dir_name = clnt->cl_program->pipe_dir_name; 125 char name[15]; 126 struct dentry *dir, *dentry; 127 128 dir = rpc_d_lookup_sb(sb, dir_name); 129 if (dir == NULL) { 130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 131 return dir; 132 } 133 for (;;) { 134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 135 name[sizeof(name) - 1] = '\0'; 136 dentry = rpc_create_client_dir(dir, name, clnt); 137 if (!IS_ERR(dentry)) 138 break; 139 if (dentry == ERR_PTR(-EEXIST)) 140 continue; 141 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 142 " %s/%s, error %ld\n", 143 dir_name, name, PTR_ERR(dentry)); 144 break; 145 } 146 dput(dir); 147 return dentry; 148} 149 150static int 151rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt) 152{ 153 struct dentry *dentry; 154 155 if (clnt->cl_program->pipe_dir_name != NULL) { 156 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); 157 if (IS_ERR(dentry)) 158 return PTR_ERR(dentry); 159 } 160 return 0; 161} 162 163static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 164{ 165 if (clnt->cl_program->pipe_dir_name == NULL) 166 return 1; 167 168 switch (event) { 169 case RPC_PIPEFS_MOUNT: 170 if (clnt->cl_pipedir_objects.pdh_dentry != NULL) 171 return 1; 172 if (atomic_read(&clnt->cl_count) == 0) 173 return 1; 174 break; 175 case RPC_PIPEFS_UMOUNT: 176 if (clnt->cl_pipedir_objects.pdh_dentry == NULL) 177 return 1; 178 break; 179 } 180 return 0; 181} 182 183static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 184 struct super_block *sb) 185{ 186 struct dentry *dentry; 187 int err = 0; 188 189 switch (event) { 190 case RPC_PIPEFS_MOUNT: 191 dentry = rpc_setup_pipedir_sb(sb, clnt); 192 if (!dentry) 193 return -ENOENT; 194 if (IS_ERR(dentry)) 195 return PTR_ERR(dentry); 196 break; 197 case RPC_PIPEFS_UMOUNT: 198 __rpc_clnt_remove_pipedir(clnt); 199 break; 200 default: 201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 202 return -ENOTSUPP; 203 } 204 return err; 205} 206 207static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 208 struct super_block *sb) 209{ 210 int error = 0; 211 212 for (;; clnt = clnt->cl_parent) { 213 if (!rpc_clnt_skip_event(clnt, event)) 214 error = __rpc_clnt_handle_event(clnt, event, sb); 215 if (error || clnt == clnt->cl_parent) 216 break; 217 } 218 return error; 219} 220 221static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 222{ 223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 224 struct rpc_clnt *clnt; 225 226 spin_lock(&sn->rpc_client_lock); 227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 228 if (rpc_clnt_skip_event(clnt, event)) 229 continue; 230 spin_unlock(&sn->rpc_client_lock); 231 return clnt; 232 } 233 spin_unlock(&sn->rpc_client_lock); 234 return NULL; 235} 236 237static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 238 void *ptr) 239{ 240 struct super_block *sb = ptr; 241 struct rpc_clnt *clnt; 242 int error = 0; 243 244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 245 error = __rpc_pipefs_event(clnt, event, sb); 246 if (error) 247 break; 248 } 249 return error; 250} 251 252static struct notifier_block rpc_clients_block = { 253 .notifier_call = rpc_pipefs_event, 254 .priority = SUNRPC_PIPEFS_RPC_PRIO, 255}; 256 257int rpc_clients_notifier_register(void) 258{ 259 return rpc_pipefs_notifier_register(&rpc_clients_block); 260} 261 262void rpc_clients_notifier_unregister(void) 263{ 264 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 265} 266 267static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, 268 struct rpc_xprt *xprt, 269 const struct rpc_timeout *timeout) 270{ 271 struct rpc_xprt *old; 272 273 spin_lock(&clnt->cl_lock); 274 old = rcu_dereference_protected(clnt->cl_xprt, 275 lockdep_is_held(&clnt->cl_lock)); 276 277 if (!xprt_bound(xprt)) 278 clnt->cl_autobind = 1; 279 280 clnt->cl_timeout = timeout; 281 rcu_assign_pointer(clnt->cl_xprt, xprt); 282 spin_unlock(&clnt->cl_lock); 283 284 return old; 285} 286 287static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 288{ 289 clnt->cl_nodelen = strlen(nodename); 290 if (clnt->cl_nodelen > UNX_MAXNODENAME) 291 clnt->cl_nodelen = UNX_MAXNODENAME; 292 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen); 293} 294 295static int rpc_client_register(struct rpc_clnt *clnt, 296 rpc_authflavor_t pseudoflavor, 297 const char *client_name) 298{ 299 struct rpc_auth_create_args auth_args = { 300 .pseudoflavor = pseudoflavor, 301 .target_name = client_name, 302 }; 303 struct rpc_auth *auth; 304 struct net *net = rpc_net_ns(clnt); 305 struct super_block *pipefs_sb; 306 int err; 307 308 pipefs_sb = rpc_get_sb_net(net); 309 if (pipefs_sb) { 310 err = rpc_setup_pipedir(pipefs_sb, clnt); 311 if (err) 312 goto out; 313 } 314 315 rpc_register_client(clnt); 316 if (pipefs_sb) 317 rpc_put_sb_net(net); 318 319 auth = rpcauth_create(&auth_args, clnt); 320 if (IS_ERR(auth)) { 321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 322 pseudoflavor); 323 err = PTR_ERR(auth); 324 goto err_auth; 325 } 326 return 0; 327err_auth: 328 pipefs_sb = rpc_get_sb_net(net); 329 rpc_unregister_client(clnt); 330 __rpc_clnt_remove_pipedir(clnt); 331out: 332 if (pipefs_sb) 333 rpc_put_sb_net(net); 334 return err; 335} 336 337static DEFINE_IDA(rpc_clids); 338 339static int rpc_alloc_clid(struct rpc_clnt *clnt) 340{ 341 int clid; 342 343 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL); 344 if (clid < 0) 345 return clid; 346 clnt->cl_clid = clid; 347 return 0; 348} 349 350static void rpc_free_clid(struct rpc_clnt *clnt) 351{ 352 ida_simple_remove(&rpc_clids, clnt->cl_clid); 353} 354 355static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 356 struct rpc_xprt *xprt, 357 struct rpc_clnt *parent) 358{ 359 const struct rpc_program *program = args->program; 360 const struct rpc_version *version; 361 struct rpc_clnt *clnt = NULL; 362 const struct rpc_timeout *timeout; 363 int err; 364 365 /* sanity check the name before trying to print it */ 366 dprintk("RPC: creating %s client for %s (xprt %p)\n", 367 program->name, args->servername, xprt); 368 369 err = rpciod_up(); 370 if (err) 371 goto out_no_rpciod; 372 373 err = -EINVAL; 374 if (args->version >= program->nrvers) 375 goto out_err; 376 version = program->version[args->version]; 377 if (version == NULL) 378 goto out_err; 379 380 err = -ENOMEM; 381 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 382 if (!clnt) 383 goto out_err; 384 clnt->cl_parent = parent ? : clnt; 385 386 err = rpc_alloc_clid(clnt); 387 if (err) 388 goto out_no_clid; 389 390 clnt->cl_procinfo = version->procs; 391 clnt->cl_maxproc = version->nrprocs; 392 clnt->cl_prog = args->prognumber ? : program->number; 393 clnt->cl_vers = version->number; 394 clnt->cl_stats = program->stats; 395 clnt->cl_metrics = rpc_alloc_iostats(clnt); 396 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 397 err = -ENOMEM; 398 if (clnt->cl_metrics == NULL) 399 goto out_no_stats; 400 clnt->cl_program = program; 401 INIT_LIST_HEAD(&clnt->cl_tasks); 402 spin_lock_init(&clnt->cl_lock); 403 404 timeout = xprt->timeout; 405 if (args->timeout != NULL) { 406 memcpy(&clnt->cl_timeout_default, args->timeout, 407 sizeof(clnt->cl_timeout_default)); 408 timeout = &clnt->cl_timeout_default; 409 } 410 411 rpc_clnt_set_transport(clnt, xprt, timeout); 412 413 clnt->cl_rtt = &clnt->cl_rtt_default; 414 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 415 416 atomic_set(&clnt->cl_count, 1); 417 418 /* save the nodename */ 419 rpc_clnt_set_nodename(clnt, utsname()->nodename); 420 421 err = rpc_client_register(clnt, args->authflavor, args->client_name); 422 if (err) 423 goto out_no_path; 424 if (parent) 425 atomic_inc(&parent->cl_count); 426 return clnt; 427 428out_no_path: 429 rpc_free_iostats(clnt->cl_metrics); 430out_no_stats: 431 rpc_free_clid(clnt); 432out_no_clid: 433 kfree(clnt); 434out_err: 435 rpciod_down(); 436out_no_rpciod: 437 xprt_put(xprt); 438 return ERR_PTR(err); 439} 440 441struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 442 struct rpc_xprt *xprt) 443{ 444 struct rpc_clnt *clnt = NULL; 445 446 clnt = rpc_new_client(args, xprt, NULL); 447 if (IS_ERR(clnt)) 448 return clnt; 449 450 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 451 int err = rpc_ping(clnt); 452 if (err != 0) { 453 rpc_shutdown_client(clnt); 454 return ERR_PTR(err); 455 } 456 } 457 458 clnt->cl_softrtry = 1; 459 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 460 clnt->cl_softrtry = 0; 461 462 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 463 clnt->cl_autobind = 1; 464 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 465 clnt->cl_noretranstimeo = 1; 466 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 467 clnt->cl_discrtry = 1; 468 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 469 clnt->cl_chatty = 1; 470 471 return clnt; 472} 473EXPORT_SYMBOL_GPL(rpc_create_xprt); 474 475/** 476 * rpc_create - create an RPC client and transport with one call 477 * @args: rpc_clnt create argument structure 478 * 479 * Creates and initializes an RPC transport and an RPC client. 480 * 481 * It can ping the server in order to determine if it is up, and to see if 482 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 483 * this behavior so asynchronous tasks can also use rpc_create. 484 */ 485struct rpc_clnt *rpc_create(struct rpc_create_args *args) 486{ 487 struct rpc_xprt *xprt; 488 struct xprt_create xprtargs = { 489 .net = args->net, 490 .ident = args->protocol, 491 .srcaddr = args->saddress, 492 .dstaddr = args->address, 493 .addrlen = args->addrsize, 494 .servername = args->servername, 495 .bc_xprt = args->bc_xprt, 496 }; 497 char servername[48]; 498 499 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 500 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 501 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 502 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 503 /* 504 * If the caller chooses not to specify a hostname, whip 505 * up a string representation of the passed-in address. 506 */ 507 if (xprtargs.servername == NULL) { 508 struct sockaddr_un *sun = 509 (struct sockaddr_un *)args->address; 510 struct sockaddr_in *sin = 511 (struct sockaddr_in *)args->address; 512 struct sockaddr_in6 *sin6 = 513 (struct sockaddr_in6 *)args->address; 514 515 servername[0] = '\0'; 516 switch (args->address->sa_family) { 517 case AF_LOCAL: 518 snprintf(servername, sizeof(servername), "%s", 519 sun->sun_path); 520 break; 521 case AF_INET: 522 snprintf(servername, sizeof(servername), "%pI4", 523 &sin->sin_addr.s_addr); 524 break; 525 case AF_INET6: 526 snprintf(servername, sizeof(servername), "%pI6", 527 &sin6->sin6_addr); 528 break; 529 default: 530 /* caller wants default server name, but 531 * address family isn't recognized. */ 532 return ERR_PTR(-EINVAL); 533 } 534 xprtargs.servername = servername; 535 } 536 537 xprt = xprt_create_transport(&xprtargs); 538 if (IS_ERR(xprt)) 539 return (struct rpc_clnt *)xprt; 540 541 /* 542 * By default, kernel RPC client connects from a reserved port. 543 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 544 * but it is always enabled for rpciod, which handles the connect 545 * operation. 546 */ 547 xprt->resvport = 1; 548 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 549 xprt->resvport = 0; 550 551 return rpc_create_xprt(args, xprt); 552} 553EXPORT_SYMBOL_GPL(rpc_create); 554 555/* 556 * This function clones the RPC client structure. It allows us to share the 557 * same transport while varying parameters such as the authentication 558 * flavour. 559 */ 560static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 561 struct rpc_clnt *clnt) 562{ 563 struct rpc_xprt *xprt; 564 struct rpc_clnt *new; 565 int err; 566 567 err = -ENOMEM; 568 rcu_read_lock(); 569 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 570 rcu_read_unlock(); 571 if (xprt == NULL) 572 goto out_err; 573 args->servername = xprt->servername; 574 575 new = rpc_new_client(args, xprt, clnt); 576 if (IS_ERR(new)) { 577 err = PTR_ERR(new); 578 goto out_err; 579 } 580 581 /* Turn off autobind on clones */ 582 new->cl_autobind = 0; 583 new->cl_softrtry = clnt->cl_softrtry; 584 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 585 new->cl_discrtry = clnt->cl_discrtry; 586 new->cl_chatty = clnt->cl_chatty; 587 return new; 588 589out_err: 590 dprintk("RPC: %s: returned error %d\n", __func__, err); 591 return ERR_PTR(err); 592} 593 594/** 595 * rpc_clone_client - Clone an RPC client structure 596 * 597 * @clnt: RPC client whose parameters are copied 598 * 599 * Returns a fresh RPC client or an ERR_PTR. 600 */ 601struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 602{ 603 struct rpc_create_args args = { 604 .program = clnt->cl_program, 605 .prognumber = clnt->cl_prog, 606 .version = clnt->cl_vers, 607 .authflavor = clnt->cl_auth->au_flavor, 608 }; 609 return __rpc_clone_client(&args, clnt); 610} 611EXPORT_SYMBOL_GPL(rpc_clone_client); 612 613/** 614 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 615 * 616 * @clnt: RPC client whose parameters are copied 617 * @flavor: security flavor for new client 618 * 619 * Returns a fresh RPC client or an ERR_PTR. 620 */ 621struct rpc_clnt * 622rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 623{ 624 struct rpc_create_args args = { 625 .program = clnt->cl_program, 626 .prognumber = clnt->cl_prog, 627 .version = clnt->cl_vers, 628 .authflavor = flavor, 629 }; 630 return __rpc_clone_client(&args, clnt); 631} 632EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 633 634/** 635 * rpc_switch_client_transport: switch the RPC transport on the fly 636 * @clnt: pointer to a struct rpc_clnt 637 * @args: pointer to the new transport arguments 638 * @timeout: pointer to the new timeout parameters 639 * 640 * This function allows the caller to switch the RPC transport for the 641 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 642 * server, for instance. It assumes that the caller has ensured that 643 * there are no active RPC tasks by using some form of locking. 644 * 645 * Returns zero if "clnt" is now using the new xprt. Otherwise a 646 * negative errno is returned, and "clnt" continues to use the old 647 * xprt. 648 */ 649int rpc_switch_client_transport(struct rpc_clnt *clnt, 650 struct xprt_create *args, 651 const struct rpc_timeout *timeout) 652{ 653 const struct rpc_timeout *old_timeo; 654 rpc_authflavor_t pseudoflavor; 655 struct rpc_xprt *xprt, *old; 656 struct rpc_clnt *parent; 657 int err; 658 659 xprt = xprt_create_transport(args); 660 if (IS_ERR(xprt)) { 661 dprintk("RPC: failed to create new xprt for clnt %p\n", 662 clnt); 663 return PTR_ERR(xprt); 664 } 665 666 pseudoflavor = clnt->cl_auth->au_flavor; 667 668 old_timeo = clnt->cl_timeout; 669 old = rpc_clnt_set_transport(clnt, xprt, timeout); 670 671 rpc_unregister_client(clnt); 672 __rpc_clnt_remove_pipedir(clnt); 673 674 /* 675 * A new transport was created. "clnt" therefore 676 * becomes the root of a new cl_parent tree. clnt's 677 * children, if it has any, still point to the old xprt. 678 */ 679 parent = clnt->cl_parent; 680 clnt->cl_parent = clnt; 681 682 /* 683 * The old rpc_auth cache cannot be re-used. GSS 684 * contexts in particular are between a single 685 * client and server. 686 */ 687 err = rpc_client_register(clnt, pseudoflavor, NULL); 688 if (err) 689 goto out_revert; 690 691 synchronize_rcu(); 692 if (parent != clnt) 693 rpc_release_client(parent); 694 xprt_put(old); 695 dprintk("RPC: replaced xprt for clnt %p\n", clnt); 696 return 0; 697 698out_revert: 699 rpc_clnt_set_transport(clnt, old, old_timeo); 700 clnt->cl_parent = parent; 701 rpc_client_register(clnt, pseudoflavor, NULL); 702 xprt_put(xprt); 703 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt); 704 return err; 705} 706EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 707 708/* 709 * Kill all tasks for the given client. 710 * XXX: kill their descendants as well? 711 */ 712void rpc_killall_tasks(struct rpc_clnt *clnt) 713{ 714 struct rpc_task *rovr; 715 716 717 if (list_empty(&clnt->cl_tasks)) 718 return; 719 dprintk("RPC: killing all tasks for client %p\n", clnt); 720 /* 721 * Spin lock all_tasks to prevent changes... 722 */ 723 spin_lock(&clnt->cl_lock); 724 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 725 if (!RPC_IS_ACTIVATED(rovr)) 726 continue; 727 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 728 rovr->tk_flags |= RPC_TASK_KILLED; 729 rpc_exit(rovr, -EIO); 730 if (RPC_IS_QUEUED(rovr)) 731 rpc_wake_up_queued_task(rovr->tk_waitqueue, 732 rovr); 733 } 734 } 735 spin_unlock(&clnt->cl_lock); 736} 737EXPORT_SYMBOL_GPL(rpc_killall_tasks); 738 739/* 740 * Properly shut down an RPC client, terminating all outstanding 741 * requests. 742 */ 743void rpc_shutdown_client(struct rpc_clnt *clnt) 744{ 745 might_sleep(); 746 747 dprintk_rcu("RPC: shutting down %s client for %s\n", 748 clnt->cl_program->name, 749 rcu_dereference(clnt->cl_xprt)->servername); 750 751 while (!list_empty(&clnt->cl_tasks)) { 752 rpc_killall_tasks(clnt); 753 wait_event_timeout(destroy_wait, 754 list_empty(&clnt->cl_tasks), 1*HZ); 755 } 756 757 rpc_release_client(clnt); 758} 759EXPORT_SYMBOL_GPL(rpc_shutdown_client); 760 761/* 762 * Free an RPC client 763 */ 764static struct rpc_clnt * 765rpc_free_client(struct rpc_clnt *clnt) 766{ 767 struct rpc_clnt *parent = NULL; 768 769 dprintk_rcu("RPC: destroying %s client for %s\n", 770 clnt->cl_program->name, 771 rcu_dereference(clnt->cl_xprt)->servername); 772 if (clnt->cl_parent != clnt) 773 parent = clnt->cl_parent; 774 rpc_clnt_remove_pipedir(clnt); 775 rpc_unregister_client(clnt); 776 rpc_free_iostats(clnt->cl_metrics); 777 clnt->cl_metrics = NULL; 778 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 779 rpciod_down(); 780 rpc_free_clid(clnt); 781 kfree(clnt); 782 return parent; 783} 784 785/* 786 * Free an RPC client 787 */ 788static struct rpc_clnt * 789rpc_free_auth(struct rpc_clnt *clnt) 790{ 791 if (clnt->cl_auth == NULL) 792 return rpc_free_client(clnt); 793 794 /* 795 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 796 * release remaining GSS contexts. This mechanism ensures 797 * that it can do so safely. 798 */ 799 atomic_inc(&clnt->cl_count); 800 rpcauth_release(clnt->cl_auth); 801 clnt->cl_auth = NULL; 802 if (atomic_dec_and_test(&clnt->cl_count)) 803 return rpc_free_client(clnt); 804 return NULL; 805} 806 807/* 808 * Release reference to the RPC client 809 */ 810void 811rpc_release_client(struct rpc_clnt *clnt) 812{ 813 dprintk("RPC: rpc_release_client(%p)\n", clnt); 814 815 do { 816 if (list_empty(&clnt->cl_tasks)) 817 wake_up(&destroy_wait); 818 if (!atomic_dec_and_test(&clnt->cl_count)) 819 break; 820 clnt = rpc_free_auth(clnt); 821 } while (clnt != NULL); 822} 823EXPORT_SYMBOL_GPL(rpc_release_client); 824 825/** 826 * rpc_bind_new_program - bind a new RPC program to an existing client 827 * @old: old rpc_client 828 * @program: rpc program to set 829 * @vers: rpc program version 830 * 831 * Clones the rpc client and sets up a new RPC program. This is mainly 832 * of use for enabling different RPC programs to share the same transport. 833 * The Sun NFSv2/v3 ACL protocol can do this. 834 */ 835struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 836 const struct rpc_program *program, 837 u32 vers) 838{ 839 struct rpc_create_args args = { 840 .program = program, 841 .prognumber = program->number, 842 .version = vers, 843 .authflavor = old->cl_auth->au_flavor, 844 }; 845 struct rpc_clnt *clnt; 846 int err; 847 848 clnt = __rpc_clone_client(&args, old); 849 if (IS_ERR(clnt)) 850 goto out; 851 err = rpc_ping(clnt); 852 if (err != 0) { 853 rpc_shutdown_client(clnt); 854 clnt = ERR_PTR(err); 855 } 856out: 857 return clnt; 858} 859EXPORT_SYMBOL_GPL(rpc_bind_new_program); 860 861void rpc_task_release_client(struct rpc_task *task) 862{ 863 struct rpc_clnt *clnt = task->tk_client; 864 865 if (clnt != NULL) { 866 /* Remove from client task list */ 867 spin_lock(&clnt->cl_lock); 868 list_del(&task->tk_task); 869 spin_unlock(&clnt->cl_lock); 870 task->tk_client = NULL; 871 872 rpc_release_client(clnt); 873 } 874} 875 876static 877void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 878{ 879 if (clnt != NULL) { 880 rpc_task_release_client(task); 881 task->tk_client = clnt; 882 atomic_inc(&clnt->cl_count); 883 if (clnt->cl_softrtry) 884 task->tk_flags |= RPC_TASK_SOFT; 885 if (clnt->cl_noretranstimeo) 886 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 887 if (sk_memalloc_socks()) { 888 struct rpc_xprt *xprt; 889 890 rcu_read_lock(); 891 xprt = rcu_dereference(clnt->cl_xprt); 892 if (xprt->swapper) 893 task->tk_flags |= RPC_TASK_SWAPPER; 894 rcu_read_unlock(); 895 } 896 /* Add to the client's list of all tasks */ 897 spin_lock(&clnt->cl_lock); 898 list_add_tail(&task->tk_task, &clnt->cl_tasks); 899 spin_unlock(&clnt->cl_lock); 900 } 901} 902 903void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) 904{ 905 rpc_task_release_client(task); 906 rpc_task_set_client(task, clnt); 907} 908EXPORT_SYMBOL_GPL(rpc_task_reset_client); 909 910 911static void 912rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 913{ 914 if (msg != NULL) { 915 task->tk_msg.rpc_proc = msg->rpc_proc; 916 task->tk_msg.rpc_argp = msg->rpc_argp; 917 task->tk_msg.rpc_resp = msg->rpc_resp; 918 if (msg->rpc_cred != NULL) 919 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 920 } 921} 922 923/* 924 * Default callback for async RPC calls 925 */ 926static void 927rpc_default_callback(struct rpc_task *task, void *data) 928{ 929} 930 931static const struct rpc_call_ops rpc_default_ops = { 932 .rpc_call_done = rpc_default_callback, 933}; 934 935/** 936 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 937 * @task_setup_data: pointer to task initialisation data 938 */ 939struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 940{ 941 struct rpc_task *task; 942 943 task = rpc_new_task(task_setup_data); 944 if (IS_ERR(task)) 945 goto out; 946 947 rpc_task_set_client(task, task_setup_data->rpc_client); 948 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 949 950 if (task->tk_action == NULL) 951 rpc_call_start(task); 952 953 atomic_inc(&task->tk_count); 954 rpc_execute(task); 955out: 956 return task; 957} 958EXPORT_SYMBOL_GPL(rpc_run_task); 959 960/** 961 * rpc_call_sync - Perform a synchronous RPC call 962 * @clnt: pointer to RPC client 963 * @msg: RPC call parameters 964 * @flags: RPC call flags 965 */ 966int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 967{ 968 struct rpc_task *task; 969 struct rpc_task_setup task_setup_data = { 970 .rpc_client = clnt, 971 .rpc_message = msg, 972 .callback_ops = &rpc_default_ops, 973 .flags = flags, 974 }; 975 int status; 976 977 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 978 if (flags & RPC_TASK_ASYNC) { 979 rpc_release_calldata(task_setup_data.callback_ops, 980 task_setup_data.callback_data); 981 return -EINVAL; 982 } 983 984 task = rpc_run_task(&task_setup_data); 985 if (IS_ERR(task)) 986 return PTR_ERR(task); 987 status = task->tk_status; 988 rpc_put_task(task); 989 return status; 990} 991EXPORT_SYMBOL_GPL(rpc_call_sync); 992 993/** 994 * rpc_call_async - Perform an asynchronous RPC call 995 * @clnt: pointer to RPC client 996 * @msg: RPC call parameters 997 * @flags: RPC call flags 998 * @tk_ops: RPC call ops 999 * @data: user call data 1000 */ 1001int 1002rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1003 const struct rpc_call_ops *tk_ops, void *data) 1004{ 1005 struct rpc_task *task; 1006 struct rpc_task_setup task_setup_data = { 1007 .rpc_client = clnt, 1008 .rpc_message = msg, 1009 .callback_ops = tk_ops, 1010 .callback_data = data, 1011 .flags = flags|RPC_TASK_ASYNC, 1012 }; 1013 1014 task = rpc_run_task(&task_setup_data); 1015 if (IS_ERR(task)) 1016 return PTR_ERR(task); 1017 rpc_put_task(task); 1018 return 0; 1019} 1020EXPORT_SYMBOL_GPL(rpc_call_async); 1021 1022#if defined(CONFIG_SUNRPC_BACKCHANNEL) 1023/** 1024 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1025 * rpc_execute against it 1026 * @req: RPC request 1027 * @tk_ops: RPC call ops 1028 */ 1029struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 1030 const struct rpc_call_ops *tk_ops) 1031{ 1032 struct rpc_task *task; 1033 struct xdr_buf *xbufp = &req->rq_snd_buf; 1034 struct rpc_task_setup task_setup_data = { 1035 .callback_ops = tk_ops, 1036 }; 1037 1038 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1039 /* 1040 * Create an rpc_task to send the data 1041 */ 1042 task = rpc_new_task(&task_setup_data); 1043 if (IS_ERR(task)) { 1044 xprt_free_bc_request(req); 1045 goto out; 1046 } 1047 task->tk_rqstp = req; 1048 1049 /* 1050 * Set up the xdr_buf length. 1051 * This also indicates that the buffer is XDR encoded already. 1052 */ 1053 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1054 xbufp->tail[0].iov_len; 1055 1056 task->tk_action = call_bc_transmit; 1057 atomic_inc(&task->tk_count); 1058 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1059 rpc_execute(task); 1060 1061out: 1062 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1063 return task; 1064} 1065#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1066 1067void 1068rpc_call_start(struct rpc_task *task) 1069{ 1070 task->tk_action = call_start; 1071} 1072EXPORT_SYMBOL_GPL(rpc_call_start); 1073 1074/** 1075 * rpc_peeraddr - extract remote peer address from clnt's xprt 1076 * @clnt: RPC client structure 1077 * @buf: target buffer 1078 * @bufsize: length of target buffer 1079 * 1080 * Returns the number of bytes that are actually in the stored address. 1081 */ 1082size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1083{ 1084 size_t bytes; 1085 struct rpc_xprt *xprt; 1086 1087 rcu_read_lock(); 1088 xprt = rcu_dereference(clnt->cl_xprt); 1089 1090 bytes = xprt->addrlen; 1091 if (bytes > bufsize) 1092 bytes = bufsize; 1093 memcpy(buf, &xprt->addr, bytes); 1094 rcu_read_unlock(); 1095 1096 return bytes; 1097} 1098EXPORT_SYMBOL_GPL(rpc_peeraddr); 1099 1100/** 1101 * rpc_peeraddr2str - return remote peer address in printable format 1102 * @clnt: RPC client structure 1103 * @format: address format 1104 * 1105 * NB: the lifetime of the memory referenced by the returned pointer is 1106 * the same as the rpc_xprt itself. As long as the caller uses this 1107 * pointer, it must hold the RCU read lock. 1108 */ 1109const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1110 enum rpc_display_format_t format) 1111{ 1112 struct rpc_xprt *xprt; 1113 1114 xprt = rcu_dereference(clnt->cl_xprt); 1115 1116 if (xprt->address_strings[format] != NULL) 1117 return xprt->address_strings[format]; 1118 else 1119 return "unprintable"; 1120} 1121EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1122 1123static const struct sockaddr_in rpc_inaddr_loopback = { 1124 .sin_family = AF_INET, 1125 .sin_addr.s_addr = htonl(INADDR_ANY), 1126}; 1127 1128static const struct sockaddr_in6 rpc_in6addr_loopback = { 1129 .sin6_family = AF_INET6, 1130 .sin6_addr = IN6ADDR_ANY_INIT, 1131}; 1132 1133/* 1134 * Try a getsockname() on a connected datagram socket. Using a 1135 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1136 * This conserves the ephemeral port number space. 1137 * 1138 * Returns zero and fills in "buf" if successful; otherwise, a 1139 * negative errno is returned. 1140 */ 1141static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1142 struct sockaddr *buf, int buflen) 1143{ 1144 struct socket *sock; 1145 int err; 1146 1147 err = __sock_create(net, sap->sa_family, 1148 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1149 if (err < 0) { 1150 dprintk("RPC: can't create UDP socket (%d)\n", err); 1151 goto out; 1152 } 1153 1154 switch (sap->sa_family) { 1155 case AF_INET: 1156 err = kernel_bind(sock, 1157 (struct sockaddr *)&rpc_inaddr_loopback, 1158 sizeof(rpc_inaddr_loopback)); 1159 break; 1160 case AF_INET6: 1161 err = kernel_bind(sock, 1162 (struct sockaddr *)&rpc_in6addr_loopback, 1163 sizeof(rpc_in6addr_loopback)); 1164 break; 1165 default: 1166 err = -EAFNOSUPPORT; 1167 goto out; 1168 } 1169 if (err < 0) { 1170 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1171 goto out_release; 1172 } 1173 1174 err = kernel_connect(sock, sap, salen, 0); 1175 if (err < 0) { 1176 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1177 goto out_release; 1178 } 1179 1180 err = kernel_getsockname(sock, buf, &buflen); 1181 if (err < 0) { 1182 dprintk("RPC: getsockname failed (%d)\n", err); 1183 goto out_release; 1184 } 1185 1186 err = 0; 1187 if (buf->sa_family == AF_INET6) { 1188 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1189 sin6->sin6_scope_id = 0; 1190 } 1191 dprintk("RPC: %s succeeded\n", __func__); 1192 1193out_release: 1194 sock_release(sock); 1195out: 1196 return err; 1197} 1198 1199/* 1200 * Scraping a connected socket failed, so we don't have a useable 1201 * local address. Fallback: generate an address that will prevent 1202 * the server from calling us back. 1203 * 1204 * Returns zero and fills in "buf" if successful; otherwise, a 1205 * negative errno is returned. 1206 */ 1207static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1208{ 1209 switch (family) { 1210 case AF_INET: 1211 if (buflen < sizeof(rpc_inaddr_loopback)) 1212 return -EINVAL; 1213 memcpy(buf, &rpc_inaddr_loopback, 1214 sizeof(rpc_inaddr_loopback)); 1215 break; 1216 case AF_INET6: 1217 if (buflen < sizeof(rpc_in6addr_loopback)) 1218 return -EINVAL; 1219 memcpy(buf, &rpc_in6addr_loopback, 1220 sizeof(rpc_in6addr_loopback)); 1221 default: 1222 dprintk("RPC: %s: address family not supported\n", 1223 __func__); 1224 return -EAFNOSUPPORT; 1225 } 1226 dprintk("RPC: %s: succeeded\n", __func__); 1227 return 0; 1228} 1229 1230/** 1231 * rpc_localaddr - discover local endpoint address for an RPC client 1232 * @clnt: RPC client structure 1233 * @buf: target buffer 1234 * @buflen: size of target buffer, in bytes 1235 * 1236 * Returns zero and fills in "buf" and "buflen" if successful; 1237 * otherwise, a negative errno is returned. 1238 * 1239 * This works even if the underlying transport is not currently connected, 1240 * or if the upper layer never previously provided a source address. 1241 * 1242 * The result of this function call is transient: multiple calls in 1243 * succession may give different results, depending on how local 1244 * networking configuration changes over time. 1245 */ 1246int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1247{ 1248 struct sockaddr_storage address; 1249 struct sockaddr *sap = (struct sockaddr *)&address; 1250 struct rpc_xprt *xprt; 1251 struct net *net; 1252 size_t salen; 1253 int err; 1254 1255 rcu_read_lock(); 1256 xprt = rcu_dereference(clnt->cl_xprt); 1257 salen = xprt->addrlen; 1258 memcpy(sap, &xprt->addr, salen); 1259 net = get_net(xprt->xprt_net); 1260 rcu_read_unlock(); 1261 1262 rpc_set_port(sap, 0); 1263 err = rpc_sockname(net, sap, salen, buf, buflen); 1264 put_net(net); 1265 if (err != 0) 1266 /* Couldn't discover local address, return ANYADDR */ 1267 return rpc_anyaddr(sap->sa_family, buf, buflen); 1268 return 0; 1269} 1270EXPORT_SYMBOL_GPL(rpc_localaddr); 1271 1272void 1273rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1274{ 1275 struct rpc_xprt *xprt; 1276 1277 rcu_read_lock(); 1278 xprt = rcu_dereference(clnt->cl_xprt); 1279 if (xprt->ops->set_buffer_size) 1280 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1281 rcu_read_unlock(); 1282} 1283EXPORT_SYMBOL_GPL(rpc_setbufsize); 1284 1285/** 1286 * rpc_protocol - Get transport protocol number for an RPC client 1287 * @clnt: RPC client to query 1288 * 1289 */ 1290int rpc_protocol(struct rpc_clnt *clnt) 1291{ 1292 int protocol; 1293 1294 rcu_read_lock(); 1295 protocol = rcu_dereference(clnt->cl_xprt)->prot; 1296 rcu_read_unlock(); 1297 return protocol; 1298} 1299EXPORT_SYMBOL_GPL(rpc_protocol); 1300 1301/** 1302 * rpc_net_ns - Get the network namespace for this RPC client 1303 * @clnt: RPC client to query 1304 * 1305 */ 1306struct net *rpc_net_ns(struct rpc_clnt *clnt) 1307{ 1308 struct net *ret; 1309 1310 rcu_read_lock(); 1311 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1312 rcu_read_unlock(); 1313 return ret; 1314} 1315EXPORT_SYMBOL_GPL(rpc_net_ns); 1316 1317/** 1318 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1319 * @clnt: RPC client to query 1320 * 1321 * For stream transports, this is one RPC record fragment (see RFC 1322 * 1831), as we don't support multi-record requests yet. For datagram 1323 * transports, this is the size of an IP packet minus the IP, UDP, and 1324 * RPC header sizes. 1325 */ 1326size_t rpc_max_payload(struct rpc_clnt *clnt) 1327{ 1328 size_t ret; 1329 1330 rcu_read_lock(); 1331 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1332 rcu_read_unlock(); 1333 return ret; 1334} 1335EXPORT_SYMBOL_GPL(rpc_max_payload); 1336 1337/** 1338 * rpc_get_timeout - Get timeout for transport in units of HZ 1339 * @clnt: RPC client to query 1340 */ 1341unsigned long rpc_get_timeout(struct rpc_clnt *clnt) 1342{ 1343 unsigned long ret; 1344 1345 rcu_read_lock(); 1346 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval; 1347 rcu_read_unlock(); 1348 return ret; 1349} 1350EXPORT_SYMBOL_GPL(rpc_get_timeout); 1351 1352/** 1353 * rpc_force_rebind - force transport to check that remote port is unchanged 1354 * @clnt: client to rebind 1355 * 1356 */ 1357void rpc_force_rebind(struct rpc_clnt *clnt) 1358{ 1359 if (clnt->cl_autobind) { 1360 rcu_read_lock(); 1361 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1362 rcu_read_unlock(); 1363 } 1364} 1365EXPORT_SYMBOL_GPL(rpc_force_rebind); 1366 1367/* 1368 * Restart an (async) RPC call from the call_prepare state. 1369 * Usually called from within the exit handler. 1370 */ 1371int 1372rpc_restart_call_prepare(struct rpc_task *task) 1373{ 1374 if (RPC_ASSASSINATED(task)) 1375 return 0; 1376 task->tk_action = call_start; 1377 task->tk_status = 0; 1378 if (task->tk_ops->rpc_call_prepare != NULL) 1379 task->tk_action = rpc_prepare_task; 1380 return 1; 1381} 1382EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1383 1384/* 1385 * Restart an (async) RPC call. Usually called from within the 1386 * exit handler. 1387 */ 1388int 1389rpc_restart_call(struct rpc_task *task) 1390{ 1391 if (RPC_ASSASSINATED(task)) 1392 return 0; 1393 task->tk_action = call_start; 1394 task->tk_status = 0; 1395 return 1; 1396} 1397EXPORT_SYMBOL_GPL(rpc_restart_call); 1398 1399#ifdef RPC_DEBUG 1400static const char *rpc_proc_name(const struct rpc_task *task) 1401{ 1402 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1403 1404 if (proc) { 1405 if (proc->p_name) 1406 return proc->p_name; 1407 else 1408 return "NULL"; 1409 } else 1410 return "no proc"; 1411} 1412#endif 1413 1414/* 1415 * 0. Initial state 1416 * 1417 * Other FSM states can be visited zero or more times, but 1418 * this state is visited exactly once for each RPC. 1419 */ 1420static void 1421call_start(struct rpc_task *task) 1422{ 1423 struct rpc_clnt *clnt = task->tk_client; 1424 1425 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 1426 clnt->cl_program->name, clnt->cl_vers, 1427 rpc_proc_name(task), 1428 (RPC_IS_ASYNC(task) ? "async" : "sync")); 1429 1430 /* Increment call count */ 1431 task->tk_msg.rpc_proc->p_count++; 1432 clnt->cl_stats->rpccnt++; 1433 task->tk_action = call_reserve; 1434} 1435 1436/* 1437 * 1. Reserve an RPC call slot 1438 */ 1439static void 1440call_reserve(struct rpc_task *task) 1441{ 1442 dprint_status(task); 1443 1444 task->tk_status = 0; 1445 task->tk_action = call_reserveresult; 1446 xprt_reserve(task); 1447} 1448 1449static void call_retry_reserve(struct rpc_task *task); 1450 1451/* 1452 * 1b. Grok the result of xprt_reserve() 1453 */ 1454static void 1455call_reserveresult(struct rpc_task *task) 1456{ 1457 int status = task->tk_status; 1458 1459 dprint_status(task); 1460 1461 /* 1462 * After a call to xprt_reserve(), we must have either 1463 * a request slot or else an error status. 1464 */ 1465 task->tk_status = 0; 1466 if (status >= 0) { 1467 if (task->tk_rqstp) { 1468 task->tk_action = call_refresh; 1469 return; 1470 } 1471 1472 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1473 __func__, status); 1474 rpc_exit(task, -EIO); 1475 return; 1476 } 1477 1478 /* 1479 * Even though there was an error, we may have acquired 1480 * a request slot somehow. Make sure not to leak it. 1481 */ 1482 if (task->tk_rqstp) { 1483 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1484 __func__, status); 1485 xprt_release(task); 1486 } 1487 1488 switch (status) { 1489 case -ENOMEM: 1490 rpc_delay(task, HZ >> 2); 1491 case -EAGAIN: /* woken up; retry */ 1492 task->tk_action = call_retry_reserve; 1493 return; 1494 case -EIO: /* probably a shutdown */ 1495 break; 1496 default: 1497 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1498 __func__, status); 1499 break; 1500 } 1501 rpc_exit(task, status); 1502} 1503 1504/* 1505 * 1c. Retry reserving an RPC call slot 1506 */ 1507static void 1508call_retry_reserve(struct rpc_task *task) 1509{ 1510 dprint_status(task); 1511 1512 task->tk_status = 0; 1513 task->tk_action = call_reserveresult; 1514 xprt_retry_reserve(task); 1515} 1516 1517/* 1518 * 2. Bind and/or refresh the credentials 1519 */ 1520static void 1521call_refresh(struct rpc_task *task) 1522{ 1523 dprint_status(task); 1524 1525 task->tk_action = call_refreshresult; 1526 task->tk_status = 0; 1527 task->tk_client->cl_stats->rpcauthrefresh++; 1528 rpcauth_refreshcred(task); 1529} 1530 1531/* 1532 * 2a. Process the results of a credential refresh 1533 */ 1534static void 1535call_refreshresult(struct rpc_task *task) 1536{ 1537 int status = task->tk_status; 1538 1539 dprint_status(task); 1540 1541 task->tk_status = 0; 1542 task->tk_action = call_refresh; 1543 switch (status) { 1544 case 0: 1545 if (rpcauth_uptodatecred(task)) { 1546 task->tk_action = call_allocate; 1547 return; 1548 } 1549 /* Use rate-limiting and a max number of retries if refresh 1550 * had status 0 but failed to update the cred. 1551 */ 1552 case -ETIMEDOUT: 1553 rpc_delay(task, 3*HZ); 1554 case -EAGAIN: 1555 status = -EACCES; 1556 case -EKEYEXPIRED: 1557 if (!task->tk_cred_retry) 1558 break; 1559 task->tk_cred_retry--; 1560 dprintk("RPC: %5u %s: retry refresh creds\n", 1561 task->tk_pid, __func__); 1562 return; 1563 } 1564 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1565 task->tk_pid, __func__, status); 1566 rpc_exit(task, status); 1567} 1568 1569/* 1570 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1571 * (Note: buffer memory is freed in xprt_release). 1572 */ 1573static void 1574call_allocate(struct rpc_task *task) 1575{ 1576 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1577 struct rpc_rqst *req = task->tk_rqstp; 1578 struct rpc_xprt *xprt = req->rq_xprt; 1579 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1580 1581 dprint_status(task); 1582 1583 task->tk_status = 0; 1584 task->tk_action = call_bind; 1585 1586 if (req->rq_buffer) 1587 return; 1588 1589 if (proc->p_proc != 0) { 1590 BUG_ON(proc->p_arglen == 0); 1591 if (proc->p_decode != NULL) 1592 BUG_ON(proc->p_replen == 0); 1593 } 1594 1595 /* 1596 * Calculate the size (in quads) of the RPC call 1597 * and reply headers, and convert both values 1598 * to byte sizes. 1599 */ 1600 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1601 req->rq_callsize <<= 2; 1602 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1603 req->rq_rcvsize <<= 2; 1604 1605 req->rq_buffer = xprt->ops->buf_alloc(task, 1606 req->rq_callsize + req->rq_rcvsize); 1607 if (req->rq_buffer != NULL) 1608 return; 1609 1610 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1611 1612 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1613 task->tk_action = call_allocate; 1614 rpc_delay(task, HZ>>4); 1615 return; 1616 } 1617 1618 rpc_exit(task, -ERESTARTSYS); 1619} 1620 1621static inline int 1622rpc_task_need_encode(struct rpc_task *task) 1623{ 1624 return task->tk_rqstp->rq_snd_buf.len == 0; 1625} 1626 1627static inline void 1628rpc_task_force_reencode(struct rpc_task *task) 1629{ 1630 task->tk_rqstp->rq_snd_buf.len = 0; 1631 task->tk_rqstp->rq_bytes_sent = 0; 1632} 1633 1634static inline void 1635rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1636{ 1637 buf->head[0].iov_base = start; 1638 buf->head[0].iov_len = len; 1639 buf->tail[0].iov_len = 0; 1640 buf->page_len = 0; 1641 buf->flags = 0; 1642 buf->len = 0; 1643 buf->buflen = len; 1644} 1645 1646/* 1647 * 3. Encode arguments of an RPC call 1648 */ 1649static void 1650rpc_xdr_encode(struct rpc_task *task) 1651{ 1652 struct rpc_rqst *req = task->tk_rqstp; 1653 kxdreproc_t encode; 1654 __be32 *p; 1655 1656 dprint_status(task); 1657 1658 rpc_xdr_buf_init(&req->rq_snd_buf, 1659 req->rq_buffer, 1660 req->rq_callsize); 1661 rpc_xdr_buf_init(&req->rq_rcv_buf, 1662 (char *)req->rq_buffer + req->rq_callsize, 1663 req->rq_rcvsize); 1664 1665 p = rpc_encode_header(task); 1666 if (p == NULL) { 1667 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1668 rpc_exit(task, -EIO); 1669 return; 1670 } 1671 1672 encode = task->tk_msg.rpc_proc->p_encode; 1673 if (encode == NULL) 1674 return; 1675 1676 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1677 task->tk_msg.rpc_argp); 1678} 1679 1680/* 1681 * 4. Get the server port number if not yet set 1682 */ 1683static void 1684call_bind(struct rpc_task *task) 1685{ 1686 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1687 1688 dprint_status(task); 1689 1690 task->tk_action = call_connect; 1691 if (!xprt_bound(xprt)) { 1692 task->tk_action = call_bind_status; 1693 task->tk_timeout = xprt->bind_timeout; 1694 xprt->ops->rpcbind(task); 1695 } 1696} 1697 1698/* 1699 * 4a. Sort out bind result 1700 */ 1701static void 1702call_bind_status(struct rpc_task *task) 1703{ 1704 int status = -EIO; 1705 1706 if (task->tk_status >= 0) { 1707 dprint_status(task); 1708 task->tk_status = 0; 1709 task->tk_action = call_connect; 1710 return; 1711 } 1712 1713 trace_rpc_bind_status(task); 1714 switch (task->tk_status) { 1715 case -ENOMEM: 1716 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1717 rpc_delay(task, HZ >> 2); 1718 goto retry_timeout; 1719 case -EACCES: 1720 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1721 "unavailable\n", task->tk_pid); 1722 /* fail immediately if this is an RPC ping */ 1723 if (task->tk_msg.rpc_proc->p_proc == 0) { 1724 status = -EOPNOTSUPP; 1725 break; 1726 } 1727 if (task->tk_rebind_retry == 0) 1728 break; 1729 task->tk_rebind_retry--; 1730 rpc_delay(task, 3*HZ); 1731 goto retry_timeout; 1732 case -ETIMEDOUT: 1733 dprintk("RPC: %5u rpcbind request timed out\n", 1734 task->tk_pid); 1735 goto retry_timeout; 1736 case -EPFNOSUPPORT: 1737 /* server doesn't support any rpcbind version we know of */ 1738 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1739 task->tk_pid); 1740 break; 1741 case -EPROTONOSUPPORT: 1742 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1743 task->tk_pid); 1744 goto retry_timeout; 1745 case -ECONNREFUSED: /* connection problems */ 1746 case -ECONNRESET: 1747 case -ECONNABORTED: 1748 case -ENOTCONN: 1749 case -EHOSTDOWN: 1750 case -EHOSTUNREACH: 1751 case -ENETUNREACH: 1752 case -ENOBUFS: 1753 case -EPIPE: 1754 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1755 task->tk_pid, task->tk_status); 1756 if (!RPC_IS_SOFTCONN(task)) { 1757 rpc_delay(task, 5*HZ); 1758 goto retry_timeout; 1759 } 1760 status = task->tk_status; 1761 break; 1762 default: 1763 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1764 task->tk_pid, -task->tk_status); 1765 } 1766 1767 rpc_exit(task, status); 1768 return; 1769 1770retry_timeout: 1771 task->tk_status = 0; 1772 task->tk_action = call_timeout; 1773} 1774 1775/* 1776 * 4b. Connect to the RPC server 1777 */ 1778static void 1779call_connect(struct rpc_task *task) 1780{ 1781 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1782 1783 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1784 task->tk_pid, xprt, 1785 (xprt_connected(xprt) ? "is" : "is not")); 1786 1787 task->tk_action = call_transmit; 1788 if (!xprt_connected(xprt)) { 1789 task->tk_action = call_connect_status; 1790 if (task->tk_status < 0) 1791 return; 1792 if (task->tk_flags & RPC_TASK_NOCONNECT) { 1793 rpc_exit(task, -ENOTCONN); 1794 return; 1795 } 1796 xprt_connect(task); 1797 } 1798} 1799 1800/* 1801 * 4c. Sort out connect result 1802 */ 1803static void 1804call_connect_status(struct rpc_task *task) 1805{ 1806 struct rpc_clnt *clnt = task->tk_client; 1807 int status = task->tk_status; 1808 1809 dprint_status(task); 1810 1811 trace_rpc_connect_status(task, status); 1812 task->tk_status = 0; 1813 switch (status) { 1814 case -ECONNREFUSED: 1815 case -ECONNRESET: 1816 case -ECONNABORTED: 1817 case -ENETUNREACH: 1818 case -EHOSTUNREACH: 1819 case -ENOBUFS: 1820 case -EPIPE: 1821 if (RPC_IS_SOFTCONN(task)) 1822 break; 1823 /* retry with existing socket, after a delay */ 1824 rpc_delay(task, 3*HZ); 1825 case -EAGAIN: 1826 /* Check for timeouts before looping back to call_bind */ 1827 case -ETIMEDOUT: 1828 task->tk_action = call_timeout; 1829 return; 1830 case 0: 1831 clnt->cl_stats->netreconn++; 1832 task->tk_action = call_transmit; 1833 return; 1834 } 1835 rpc_exit(task, status); 1836} 1837 1838/* 1839 * 5. Transmit the RPC request, and wait for reply 1840 */ 1841static void 1842call_transmit(struct rpc_task *task) 1843{ 1844 int is_retrans = RPC_WAS_SENT(task); 1845 1846 dprint_status(task); 1847 1848 task->tk_action = call_status; 1849 if (task->tk_status < 0) 1850 return; 1851 if (!xprt_prepare_transmit(task)) 1852 return; 1853 task->tk_action = call_transmit_status; 1854 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1855 if (rpc_task_need_encode(task)) { 1856 rpc_xdr_encode(task); 1857 /* Did the encode result in an error condition? */ 1858 if (task->tk_status != 0) { 1859 /* Was the error nonfatal? */ 1860 if (task->tk_status == -EAGAIN) 1861 rpc_delay(task, HZ >> 4); 1862 else 1863 rpc_exit(task, task->tk_status); 1864 return; 1865 } 1866 } 1867 xprt_transmit(task); 1868 if (task->tk_status < 0) 1869 return; 1870 if (is_retrans) 1871 task->tk_client->cl_stats->rpcretrans++; 1872 /* 1873 * On success, ensure that we call xprt_end_transmit() before sleeping 1874 * in order to allow access to the socket to other RPC requests. 1875 */ 1876 call_transmit_status(task); 1877 if (rpc_reply_expected(task)) 1878 return; 1879 task->tk_action = rpc_exit_task; 1880 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task); 1881} 1882 1883/* 1884 * 5a. Handle cleanup after a transmission 1885 */ 1886static void 1887call_transmit_status(struct rpc_task *task) 1888{ 1889 task->tk_action = call_status; 1890 1891 /* 1892 * Common case: success. Force the compiler to put this 1893 * test first. 1894 */ 1895 if (task->tk_status == 0) { 1896 xprt_end_transmit(task); 1897 rpc_task_force_reencode(task); 1898 return; 1899 } 1900 1901 switch (task->tk_status) { 1902 case -EAGAIN: 1903 break; 1904 default: 1905 dprint_status(task); 1906 xprt_end_transmit(task); 1907 rpc_task_force_reencode(task); 1908 break; 1909 /* 1910 * Special cases: if we've been waiting on the 1911 * socket's write_space() callback, or if the 1912 * socket just returned a connection error, 1913 * then hold onto the transport lock. 1914 */ 1915 case -ECONNREFUSED: 1916 case -EHOSTDOWN: 1917 case -EHOSTUNREACH: 1918 case -ENETUNREACH: 1919 case -EPERM: 1920 if (RPC_IS_SOFTCONN(task)) { 1921 xprt_end_transmit(task); 1922 rpc_exit(task, task->tk_status); 1923 break; 1924 } 1925 case -ECONNRESET: 1926 case -ECONNABORTED: 1927 case -ENOTCONN: 1928 case -ENOBUFS: 1929 case -EPIPE: 1930 rpc_task_force_reencode(task); 1931 } 1932} 1933 1934#if defined(CONFIG_SUNRPC_BACKCHANNEL) 1935/* 1936 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 1937 * addition, disconnect on connectivity errors. 1938 */ 1939static void 1940call_bc_transmit(struct rpc_task *task) 1941{ 1942 struct rpc_rqst *req = task->tk_rqstp; 1943 1944 if (!xprt_prepare_transmit(task)) { 1945 /* 1946 * Could not reserve the transport. Try again after the 1947 * transport is released. 1948 */ 1949 task->tk_status = 0; 1950 task->tk_action = call_bc_transmit; 1951 return; 1952 } 1953 1954 task->tk_action = rpc_exit_task; 1955 if (task->tk_status < 0) { 1956 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1957 "error: %d\n", task->tk_status); 1958 return; 1959 } 1960 1961 xprt_transmit(task); 1962 xprt_end_transmit(task); 1963 dprint_status(task); 1964 switch (task->tk_status) { 1965 case 0: 1966 /* Success */ 1967 break; 1968 case -EHOSTDOWN: 1969 case -EHOSTUNREACH: 1970 case -ENETUNREACH: 1971 case -ETIMEDOUT: 1972 /* 1973 * Problem reaching the server. Disconnect and let the 1974 * forechannel reestablish the connection. The server will 1975 * have to retransmit the backchannel request and we'll 1976 * reprocess it. Since these ops are idempotent, there's no 1977 * need to cache our reply at this time. 1978 */ 1979 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1980 "error: %d\n", task->tk_status); 1981 xprt_conditional_disconnect(req->rq_xprt, 1982 req->rq_connect_cookie); 1983 break; 1984 default: 1985 /* 1986 * We were unable to reply and will have to drop the 1987 * request. The server should reconnect and retransmit. 1988 */ 1989 WARN_ON_ONCE(task->tk_status == -EAGAIN); 1990 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1991 "error: %d\n", task->tk_status); 1992 break; 1993 } 1994 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 1995} 1996#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1997 1998/* 1999 * 6. Sort out the RPC call status 2000 */ 2001static void 2002call_status(struct rpc_task *task) 2003{ 2004 struct rpc_clnt *clnt = task->tk_client; 2005 struct rpc_rqst *req = task->tk_rqstp; 2006 int status; 2007 2008 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 2009 task->tk_status = req->rq_reply_bytes_recvd; 2010 2011 dprint_status(task); 2012 2013 status = task->tk_status; 2014 if (status >= 0) { 2015 task->tk_action = call_decode; 2016 return; 2017 } 2018 2019 trace_rpc_call_status(task); 2020 task->tk_status = 0; 2021 switch(status) { 2022 case -EHOSTDOWN: 2023 case -EHOSTUNREACH: 2024 case -ENETUNREACH: 2025 case -EPERM: 2026 if (RPC_IS_SOFTCONN(task)) { 2027 rpc_exit(task, status); 2028 break; 2029 } 2030 /* 2031 * Delay any retries for 3 seconds, then handle as if it 2032 * were a timeout. 2033 */ 2034 rpc_delay(task, 3*HZ); 2035 case -ETIMEDOUT: 2036 task->tk_action = call_timeout; 2037 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) 2038 && task->tk_client->cl_discrtry) 2039 xprt_conditional_disconnect(req->rq_xprt, 2040 req->rq_connect_cookie); 2041 break; 2042 case -ECONNREFUSED: 2043 case -ECONNRESET: 2044 case -ECONNABORTED: 2045 rpc_force_rebind(clnt); 2046 case -ENOBUFS: 2047 rpc_delay(task, 3*HZ); 2048 case -EPIPE: 2049 case -ENOTCONN: 2050 task->tk_action = call_bind; 2051 break; 2052 case -EAGAIN: 2053 task->tk_action = call_transmit; 2054 break; 2055 case -EIO: 2056 /* shutdown or soft timeout */ 2057 rpc_exit(task, status); 2058 break; 2059 default: 2060 if (clnt->cl_chatty) 2061 printk("%s: RPC call returned error %d\n", 2062 clnt->cl_program->name, -status); 2063 rpc_exit(task, status); 2064 } 2065} 2066 2067/* 2068 * 6a. Handle RPC timeout 2069 * We do not release the request slot, so we keep using the 2070 * same XID for all retransmits. 2071 */ 2072static void 2073call_timeout(struct rpc_task *task) 2074{ 2075 struct rpc_clnt *clnt = task->tk_client; 2076 2077 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 2078 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 2079 goto retry; 2080 } 2081 2082 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 2083 task->tk_timeouts++; 2084 2085 if (RPC_IS_SOFTCONN(task)) { 2086 rpc_exit(task, -ETIMEDOUT); 2087 return; 2088 } 2089 if (RPC_IS_SOFT(task)) { 2090 if (clnt->cl_chatty) { 2091 rcu_read_lock(); 2092 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 2093 clnt->cl_program->name, 2094 rcu_dereference(clnt->cl_xprt)->servername); 2095 rcu_read_unlock(); 2096 } 2097 if (task->tk_flags & RPC_TASK_TIMEOUT) 2098 rpc_exit(task, -ETIMEDOUT); 2099 else 2100 rpc_exit(task, -EIO); 2101 return; 2102 } 2103 2104 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2105 task->tk_flags |= RPC_CALL_MAJORSEEN; 2106 if (clnt->cl_chatty) { 2107 rcu_read_lock(); 2108 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 2109 clnt->cl_program->name, 2110 rcu_dereference(clnt->cl_xprt)->servername); 2111 rcu_read_unlock(); 2112 } 2113 } 2114 rpc_force_rebind(clnt); 2115 /* 2116 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2117 * event? RFC2203 requires the server to drop all such requests. 2118 */ 2119 rpcauth_invalcred(task); 2120 2121retry: 2122 task->tk_action = call_bind; 2123 task->tk_status = 0; 2124} 2125 2126/* 2127 * 7. Decode the RPC reply 2128 */ 2129static void 2130call_decode(struct rpc_task *task) 2131{ 2132 struct rpc_clnt *clnt = task->tk_client; 2133 struct rpc_rqst *req = task->tk_rqstp; 2134 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 2135 __be32 *p; 2136 2137 dprint_status(task); 2138 2139 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2140 if (clnt->cl_chatty) { 2141 rcu_read_lock(); 2142 printk(KERN_NOTICE "%s: server %s OK\n", 2143 clnt->cl_program->name, 2144 rcu_dereference(clnt->cl_xprt)->servername); 2145 rcu_read_unlock(); 2146 } 2147 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2148 } 2149 2150 /* 2151 * Ensure that we see all writes made by xprt_complete_rqst() 2152 * before it changed req->rq_reply_bytes_recvd. 2153 */ 2154 smp_rmb(); 2155 req->rq_rcv_buf.len = req->rq_private_buf.len; 2156 2157 /* Check that the softirq receive buffer is valid */ 2158 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2159 sizeof(req->rq_rcv_buf)) != 0); 2160 2161 if (req->rq_rcv_buf.len < 12) { 2162 if (!RPC_IS_SOFT(task)) { 2163 task->tk_action = call_bind; 2164 goto out_retry; 2165 } 2166 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 2167 clnt->cl_program->name, task->tk_status); 2168 task->tk_action = call_timeout; 2169 goto out_retry; 2170 } 2171 2172 p = rpc_verify_header(task); 2173 if (IS_ERR(p)) { 2174 if (p == ERR_PTR(-EAGAIN)) 2175 goto out_retry; 2176 return; 2177 } 2178 2179 task->tk_action = rpc_exit_task; 2180 2181 if (decode) { 2182 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 2183 task->tk_msg.rpc_resp); 2184 } 2185 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 2186 task->tk_status); 2187 return; 2188out_retry: 2189 task->tk_status = 0; 2190 /* Note: rpc_verify_header() may have freed the RPC slot */ 2191 if (task->tk_rqstp == req) { 2192 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 2193 if (task->tk_client->cl_discrtry) 2194 xprt_conditional_disconnect(req->rq_xprt, 2195 req->rq_connect_cookie); 2196 } 2197} 2198 2199static __be32 * 2200rpc_encode_header(struct rpc_task *task) 2201{ 2202 struct rpc_clnt *clnt = task->tk_client; 2203 struct rpc_rqst *req = task->tk_rqstp; 2204 __be32 *p = req->rq_svec[0].iov_base; 2205 2206 /* FIXME: check buffer size? */ 2207 2208 p = xprt_skip_transport_header(req->rq_xprt, p); 2209 *p++ = req->rq_xid; /* XID */ 2210 *p++ = htonl(RPC_CALL); /* CALL */ 2211 *p++ = htonl(RPC_VERSION); /* RPC version */ 2212 *p++ = htonl(clnt->cl_prog); /* program number */ 2213 *p++ = htonl(clnt->cl_vers); /* program version */ 2214 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 2215 p = rpcauth_marshcred(task, p); 2216 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 2217 return p; 2218} 2219 2220static __be32 * 2221rpc_verify_header(struct rpc_task *task) 2222{ 2223 struct rpc_clnt *clnt = task->tk_client; 2224 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 2225 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 2226 __be32 *p = iov->iov_base; 2227 u32 n; 2228 int error = -EACCES; 2229 2230 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 2231 /* RFC-1014 says that the representation of XDR data must be a 2232 * multiple of four bytes 2233 * - if it isn't pointer subtraction in the NFS client may give 2234 * undefined results 2235 */ 2236 dprintk("RPC: %5u %s: XDR representation not a multiple of" 2237 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 2238 task->tk_rqstp->rq_rcv_buf.len); 2239 error = -EIO; 2240 goto out_err; 2241 } 2242 if ((len -= 3) < 0) 2243 goto out_overflow; 2244 2245 p += 1; /* skip XID */ 2246 if ((n = ntohl(*p++)) != RPC_REPLY) { 2247 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 2248 task->tk_pid, __func__, n); 2249 error = -EIO; 2250 goto out_garbage; 2251 } 2252 2253 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 2254 if (--len < 0) 2255 goto out_overflow; 2256 switch ((n = ntohl(*p++))) { 2257 case RPC_AUTH_ERROR: 2258 break; 2259 case RPC_MISMATCH: 2260 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 2261 task->tk_pid, __func__); 2262 error = -EPROTONOSUPPORT; 2263 goto out_err; 2264 default: 2265 dprintk("RPC: %5u %s: RPC call rejected, " 2266 "unknown error: %x\n", 2267 task->tk_pid, __func__, n); 2268 error = -EIO; 2269 goto out_err; 2270 } 2271 if (--len < 0) 2272 goto out_overflow; 2273 switch ((n = ntohl(*p++))) { 2274 case RPC_AUTH_REJECTEDCRED: 2275 case RPC_AUTH_REJECTEDVERF: 2276 case RPCSEC_GSS_CREDPROBLEM: 2277 case RPCSEC_GSS_CTXPROBLEM: 2278 if (!task->tk_cred_retry) 2279 break; 2280 task->tk_cred_retry--; 2281 dprintk("RPC: %5u %s: retry stale creds\n", 2282 task->tk_pid, __func__); 2283 rpcauth_invalcred(task); 2284 /* Ensure we obtain a new XID! */ 2285 xprt_release(task); 2286 task->tk_action = call_reserve; 2287 goto out_retry; 2288 case RPC_AUTH_BADCRED: 2289 case RPC_AUTH_BADVERF: 2290 /* possibly garbled cred/verf? */ 2291 if (!task->tk_garb_retry) 2292 break; 2293 task->tk_garb_retry--; 2294 dprintk("RPC: %5u %s: retry garbled creds\n", 2295 task->tk_pid, __func__); 2296 task->tk_action = call_bind; 2297 goto out_retry; 2298 case RPC_AUTH_TOOWEAK: 2299 rcu_read_lock(); 2300 printk(KERN_NOTICE "RPC: server %s requires stronger " 2301 "authentication.\n", 2302 rcu_dereference(clnt->cl_xprt)->servername); 2303 rcu_read_unlock(); 2304 break; 2305 default: 2306 dprintk("RPC: %5u %s: unknown auth error: %x\n", 2307 task->tk_pid, __func__, n); 2308 error = -EIO; 2309 } 2310 dprintk("RPC: %5u %s: call rejected %d\n", 2311 task->tk_pid, __func__, n); 2312 goto out_err; 2313 } 2314 p = rpcauth_checkverf(task, p); 2315 if (IS_ERR(p)) { 2316 error = PTR_ERR(p); 2317 dprintk("RPC: %5u %s: auth check failed with %d\n", 2318 task->tk_pid, __func__, error); 2319 goto out_garbage; /* bad verifier, retry */ 2320 } 2321 len = p - (__be32 *)iov->iov_base - 1; 2322 if (len < 0) 2323 goto out_overflow; 2324 switch ((n = ntohl(*p++))) { 2325 case RPC_SUCCESS: 2326 return p; 2327 case RPC_PROG_UNAVAIL: 2328 dprintk_rcu("RPC: %5u %s: program %u is unsupported " 2329 "by server %s\n", task->tk_pid, __func__, 2330 (unsigned int)clnt->cl_prog, 2331 rcu_dereference(clnt->cl_xprt)->servername); 2332 error = -EPFNOSUPPORT; 2333 goto out_err; 2334 case RPC_PROG_MISMATCH: 2335 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported " 2336 "by server %s\n", task->tk_pid, __func__, 2337 (unsigned int)clnt->cl_prog, 2338 (unsigned int)clnt->cl_vers, 2339 rcu_dereference(clnt->cl_xprt)->servername); 2340 error = -EPROTONOSUPPORT; 2341 goto out_err; 2342 case RPC_PROC_UNAVAIL: 2343 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, " 2344 "version %u on server %s\n", 2345 task->tk_pid, __func__, 2346 rpc_proc_name(task), 2347 clnt->cl_prog, clnt->cl_vers, 2348 rcu_dereference(clnt->cl_xprt)->servername); 2349 error = -EOPNOTSUPP; 2350 goto out_err; 2351 case RPC_GARBAGE_ARGS: 2352 dprintk("RPC: %5u %s: server saw garbage\n", 2353 task->tk_pid, __func__); 2354 break; /* retry */ 2355 default: 2356 dprintk("RPC: %5u %s: server accept status: %x\n", 2357 task->tk_pid, __func__, n); 2358 /* Also retry */ 2359 } 2360 2361out_garbage: 2362 clnt->cl_stats->rpcgarbage++; 2363 if (task->tk_garb_retry) { 2364 task->tk_garb_retry--; 2365 dprintk("RPC: %5u %s: retrying\n", 2366 task->tk_pid, __func__); 2367 task->tk_action = call_bind; 2368out_retry: 2369 return ERR_PTR(-EAGAIN); 2370 } 2371out_err: 2372 rpc_exit(task, error); 2373 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 2374 __func__, error); 2375 return ERR_PTR(error); 2376out_overflow: 2377 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 2378 __func__); 2379 goto out_garbage; 2380} 2381 2382static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2383{ 2384} 2385 2386static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2387{ 2388 return 0; 2389} 2390 2391static struct rpc_procinfo rpcproc_null = { 2392 .p_encode = rpcproc_encode_null, 2393 .p_decode = rpcproc_decode_null, 2394}; 2395 2396static int rpc_ping(struct rpc_clnt *clnt) 2397{ 2398 struct rpc_message msg = { 2399 .rpc_proc = &rpcproc_null, 2400 }; 2401 int err; 2402 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2403 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 2404 put_rpccred(msg.rpc_cred); 2405 return err; 2406} 2407 2408struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2409{ 2410 struct rpc_message msg = { 2411 .rpc_proc = &rpcproc_null, 2412 .rpc_cred = cred, 2413 }; 2414 struct rpc_task_setup task_setup_data = { 2415 .rpc_client = clnt, 2416 .rpc_message = &msg, 2417 .callback_ops = &rpc_default_ops, 2418 .flags = flags, 2419 }; 2420 return rpc_run_task(&task_setup_data); 2421} 2422EXPORT_SYMBOL_GPL(rpc_call_null); 2423 2424#ifdef RPC_DEBUG 2425static void rpc_show_header(void) 2426{ 2427 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 2428 "-timeout ---ops--\n"); 2429} 2430 2431static void rpc_show_task(const struct rpc_clnt *clnt, 2432 const struct rpc_task *task) 2433{ 2434 const char *rpc_waitq = "none"; 2435 2436 if (RPC_IS_QUEUED(task)) 2437 rpc_waitq = rpc_qname(task->tk_waitqueue); 2438 2439 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 2440 task->tk_pid, task->tk_flags, task->tk_status, 2441 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 2442 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 2443 task->tk_action, rpc_waitq); 2444} 2445 2446void rpc_show_tasks(struct net *net) 2447{ 2448 struct rpc_clnt *clnt; 2449 struct rpc_task *task; 2450 int header = 0; 2451 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 2452 2453 spin_lock(&sn->rpc_client_lock); 2454 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 2455 spin_lock(&clnt->cl_lock); 2456 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 2457 if (!header) { 2458 rpc_show_header(); 2459 header++; 2460 } 2461 rpc_show_task(clnt, task); 2462 } 2463 spin_unlock(&clnt->cl_lock); 2464 } 2465 spin_unlock(&sn->rpc_client_lock); 2466} 2467#endif 2468