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#if IS_ENABLED(CONFIG_SUNRPC_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 = strlcpy(clnt->cl_nodename, 290 nodename, sizeof(clnt->cl_nodename)); 291} 292 293static int rpc_client_register(struct rpc_clnt *clnt, 294 rpc_authflavor_t pseudoflavor, 295 const char *client_name) 296{ 297 struct rpc_auth_create_args auth_args = { 298 .pseudoflavor = pseudoflavor, 299 .target_name = client_name, 300 }; 301 struct rpc_auth *auth; 302 struct net *net = rpc_net_ns(clnt); 303 struct super_block *pipefs_sb; 304 int err; 305 306 rpc_clnt_debugfs_register(clnt); 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 rpc_clnt_debugfs_unregister(clnt); 335 return err; 336} 337 338static DEFINE_IDA(rpc_clids); 339 340static int rpc_alloc_clid(struct rpc_clnt *clnt) 341{ 342 int clid; 343 344 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL); 345 if (clid < 0) 346 return clid; 347 clnt->cl_clid = clid; 348 return 0; 349} 350 351static void rpc_free_clid(struct rpc_clnt *clnt) 352{ 353 ida_simple_remove(&rpc_clids, clnt->cl_clid); 354} 355 356static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 357 struct rpc_xprt *xprt, 358 struct rpc_clnt *parent) 359{ 360 const struct rpc_program *program = args->program; 361 const struct rpc_version *version; 362 struct rpc_clnt *clnt = NULL; 363 const struct rpc_timeout *timeout; 364 const char *nodename = args->nodename; 365 int err; 366 367 /* sanity check the name before trying to print it */ 368 dprintk("RPC: creating %s client for %s (xprt %p)\n", 369 program->name, args->servername, xprt); 370 371 err = rpciod_up(); 372 if (err) 373 goto out_no_rpciod; 374 375 err = -EINVAL; 376 if (args->version >= program->nrvers) 377 goto out_err; 378 version = program->version[args->version]; 379 if (version == NULL) 380 goto out_err; 381 382 err = -ENOMEM; 383 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 384 if (!clnt) 385 goto out_err; 386 clnt->cl_parent = parent ? : clnt; 387 388 err = rpc_alloc_clid(clnt); 389 if (err) 390 goto out_no_clid; 391 392 clnt->cl_procinfo = version->procs; 393 clnt->cl_maxproc = version->nrprocs; 394 clnt->cl_prog = args->prognumber ? : program->number; 395 clnt->cl_vers = version->number; 396 clnt->cl_stats = program->stats; 397 clnt->cl_metrics = rpc_alloc_iostats(clnt); 398 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 399 err = -ENOMEM; 400 if (clnt->cl_metrics == NULL) 401 goto out_no_stats; 402 clnt->cl_program = program; 403 INIT_LIST_HEAD(&clnt->cl_tasks); 404 spin_lock_init(&clnt->cl_lock); 405 406 timeout = xprt->timeout; 407 if (args->timeout != NULL) { 408 memcpy(&clnt->cl_timeout_default, args->timeout, 409 sizeof(clnt->cl_timeout_default)); 410 timeout = &clnt->cl_timeout_default; 411 } 412 413 rpc_clnt_set_transport(clnt, xprt, timeout); 414 415 clnt->cl_rtt = &clnt->cl_rtt_default; 416 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 417 418 atomic_set(&clnt->cl_count, 1); 419 420 if (nodename == NULL) 421 nodename = utsname()->nodename; 422 /* save the nodename */ 423 rpc_clnt_set_nodename(clnt, nodename); 424 425 err = rpc_client_register(clnt, args->authflavor, args->client_name); 426 if (err) 427 goto out_no_path; 428 if (parent) 429 atomic_inc(&parent->cl_count); 430 return clnt; 431 432out_no_path: 433 rpc_free_iostats(clnt->cl_metrics); 434out_no_stats: 435 rpc_free_clid(clnt); 436out_no_clid: 437 kfree(clnt); 438out_err: 439 rpciod_down(); 440out_no_rpciod: 441 xprt_put(xprt); 442 return ERR_PTR(err); 443} 444 445struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 446 struct rpc_xprt *xprt) 447{ 448 struct rpc_clnt *clnt = NULL; 449 450 clnt = rpc_new_client(args, xprt, NULL); 451 if (IS_ERR(clnt)) 452 return clnt; 453 454 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 455 int err = rpc_ping(clnt); 456 if (err != 0) { 457 rpc_shutdown_client(clnt); 458 return ERR_PTR(err); 459 } 460 } 461 462 clnt->cl_softrtry = 1; 463 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 464 clnt->cl_softrtry = 0; 465 466 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 467 clnt->cl_autobind = 1; 468 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 469 clnt->cl_noretranstimeo = 1; 470 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 471 clnt->cl_discrtry = 1; 472 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 473 clnt->cl_chatty = 1; 474 475 return clnt; 476} 477EXPORT_SYMBOL_GPL(rpc_create_xprt); 478 479/** 480 * rpc_create - create an RPC client and transport with one call 481 * @args: rpc_clnt create argument structure 482 * 483 * Creates and initializes an RPC transport and an RPC client. 484 * 485 * It can ping the server in order to determine if it is up, and to see if 486 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 487 * this behavior so asynchronous tasks can also use rpc_create. 488 */ 489struct rpc_clnt *rpc_create(struct rpc_create_args *args) 490{ 491 struct rpc_xprt *xprt; 492 struct xprt_create xprtargs = { 493 .net = args->net, 494 .ident = args->protocol, 495 .srcaddr = args->saddress, 496 .dstaddr = args->address, 497 .addrlen = args->addrsize, 498 .servername = args->servername, 499 .bc_xprt = args->bc_xprt, 500 }; 501 char servername[48]; 502 503 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 504 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 505 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 506 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 507 /* 508 * If the caller chooses not to specify a hostname, whip 509 * up a string representation of the passed-in address. 510 */ 511 if (xprtargs.servername == NULL) { 512 struct sockaddr_un *sun = 513 (struct sockaddr_un *)args->address; 514 struct sockaddr_in *sin = 515 (struct sockaddr_in *)args->address; 516 struct sockaddr_in6 *sin6 = 517 (struct sockaddr_in6 *)args->address; 518 519 servername[0] = '\0'; 520 switch (args->address->sa_family) { 521 case AF_LOCAL: 522 snprintf(servername, sizeof(servername), "%s", 523 sun->sun_path); 524 break; 525 case AF_INET: 526 snprintf(servername, sizeof(servername), "%pI4", 527 &sin->sin_addr.s_addr); 528 break; 529 case AF_INET6: 530 snprintf(servername, sizeof(servername), "%pI6", 531 &sin6->sin6_addr); 532 break; 533 default: 534 /* caller wants default server name, but 535 * address family isn't recognized. */ 536 return ERR_PTR(-EINVAL); 537 } 538 xprtargs.servername = servername; 539 } 540 541 xprt = xprt_create_transport(&xprtargs); 542 if (IS_ERR(xprt)) 543 return (struct rpc_clnt *)xprt; 544 545 /* 546 * By default, kernel RPC client connects from a reserved port. 547 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 548 * but it is always enabled for rpciod, which handles the connect 549 * operation. 550 */ 551 xprt->resvport = 1; 552 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 553 xprt->resvport = 0; 554 555 return rpc_create_xprt(args, xprt); 556} 557EXPORT_SYMBOL_GPL(rpc_create); 558 559/* 560 * This function clones the RPC client structure. It allows us to share the 561 * same transport while varying parameters such as the authentication 562 * flavour. 563 */ 564static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 565 struct rpc_clnt *clnt) 566{ 567 struct rpc_xprt *xprt; 568 struct rpc_clnt *new; 569 int err; 570 571 err = -ENOMEM; 572 rcu_read_lock(); 573 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 574 rcu_read_unlock(); 575 if (xprt == NULL) 576 goto out_err; 577 args->servername = xprt->servername; 578 args->nodename = clnt->cl_nodename; 579 580 new = rpc_new_client(args, xprt, clnt); 581 if (IS_ERR(new)) { 582 err = PTR_ERR(new); 583 goto out_err; 584 } 585 586 /* Turn off autobind on clones */ 587 new->cl_autobind = 0; 588 new->cl_softrtry = clnt->cl_softrtry; 589 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 590 new->cl_discrtry = clnt->cl_discrtry; 591 new->cl_chatty = clnt->cl_chatty; 592 return new; 593 594out_err: 595 dprintk("RPC: %s: returned error %d\n", __func__, err); 596 return ERR_PTR(err); 597} 598 599/** 600 * rpc_clone_client - Clone an RPC client structure 601 * 602 * @clnt: RPC client whose parameters are copied 603 * 604 * Returns a fresh RPC client or an ERR_PTR. 605 */ 606struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 607{ 608 struct rpc_create_args args = { 609 .program = clnt->cl_program, 610 .prognumber = clnt->cl_prog, 611 .version = clnt->cl_vers, 612 .authflavor = clnt->cl_auth->au_flavor, 613 }; 614 return __rpc_clone_client(&args, clnt); 615} 616EXPORT_SYMBOL_GPL(rpc_clone_client); 617 618/** 619 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 620 * 621 * @clnt: RPC client whose parameters are copied 622 * @flavor: security flavor for new client 623 * 624 * Returns a fresh RPC client or an ERR_PTR. 625 */ 626struct rpc_clnt * 627rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 628{ 629 struct rpc_create_args args = { 630 .program = clnt->cl_program, 631 .prognumber = clnt->cl_prog, 632 .version = clnt->cl_vers, 633 .authflavor = flavor, 634 }; 635 return __rpc_clone_client(&args, clnt); 636} 637EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 638 639/** 640 * rpc_switch_client_transport: switch the RPC transport on the fly 641 * @clnt: pointer to a struct rpc_clnt 642 * @args: pointer to the new transport arguments 643 * @timeout: pointer to the new timeout parameters 644 * 645 * This function allows the caller to switch the RPC transport for the 646 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 647 * server, for instance. It assumes that the caller has ensured that 648 * there are no active RPC tasks by using some form of locking. 649 * 650 * Returns zero if "clnt" is now using the new xprt. Otherwise a 651 * negative errno is returned, and "clnt" continues to use the old 652 * xprt. 653 */ 654int rpc_switch_client_transport(struct rpc_clnt *clnt, 655 struct xprt_create *args, 656 const struct rpc_timeout *timeout) 657{ 658 const struct rpc_timeout *old_timeo; 659 rpc_authflavor_t pseudoflavor; 660 struct rpc_xprt *xprt, *old; 661 struct rpc_clnt *parent; 662 int err; 663 664 xprt = xprt_create_transport(args); 665 if (IS_ERR(xprt)) { 666 dprintk("RPC: failed to create new xprt for clnt %p\n", 667 clnt); 668 return PTR_ERR(xprt); 669 } 670 671 pseudoflavor = clnt->cl_auth->au_flavor; 672 673 old_timeo = clnt->cl_timeout; 674 old = rpc_clnt_set_transport(clnt, xprt, timeout); 675 676 rpc_unregister_client(clnt); 677 __rpc_clnt_remove_pipedir(clnt); 678 rpc_clnt_debugfs_unregister(clnt); 679 680 /* 681 * A new transport was created. "clnt" therefore 682 * becomes the root of a new cl_parent tree. clnt's 683 * children, if it has any, still point to the old xprt. 684 */ 685 parent = clnt->cl_parent; 686 clnt->cl_parent = clnt; 687 688 /* 689 * The old rpc_auth cache cannot be re-used. GSS 690 * contexts in particular are between a single 691 * client and server. 692 */ 693 err = rpc_client_register(clnt, pseudoflavor, NULL); 694 if (err) 695 goto out_revert; 696 697 synchronize_rcu(); 698 if (parent != clnt) 699 rpc_release_client(parent); 700 xprt_put(old); 701 dprintk("RPC: replaced xprt for clnt %p\n", clnt); 702 return 0; 703 704out_revert: 705 rpc_clnt_set_transport(clnt, old, old_timeo); 706 clnt->cl_parent = parent; 707 rpc_client_register(clnt, pseudoflavor, NULL); 708 xprt_put(xprt); 709 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt); 710 return err; 711} 712EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 713 714/* 715 * Kill all tasks for the given client. 716 * XXX: kill their descendants as well? 717 */ 718void rpc_killall_tasks(struct rpc_clnt *clnt) 719{ 720 struct rpc_task *rovr; 721 722 723 if (list_empty(&clnt->cl_tasks)) 724 return; 725 dprintk("RPC: killing all tasks for client %p\n", clnt); 726 /* 727 * Spin lock all_tasks to prevent changes... 728 */ 729 spin_lock(&clnt->cl_lock); 730 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 731 if (!RPC_IS_ACTIVATED(rovr)) 732 continue; 733 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 734 rovr->tk_flags |= RPC_TASK_KILLED; 735 rpc_exit(rovr, -EIO); 736 if (RPC_IS_QUEUED(rovr)) 737 rpc_wake_up_queued_task(rovr->tk_waitqueue, 738 rovr); 739 } 740 } 741 spin_unlock(&clnt->cl_lock); 742} 743EXPORT_SYMBOL_GPL(rpc_killall_tasks); 744 745/* 746 * Properly shut down an RPC client, terminating all outstanding 747 * requests. 748 */ 749void rpc_shutdown_client(struct rpc_clnt *clnt) 750{ 751 might_sleep(); 752 753 dprintk_rcu("RPC: shutting down %s client for %s\n", 754 clnt->cl_program->name, 755 rcu_dereference(clnt->cl_xprt)->servername); 756 757 while (!list_empty(&clnt->cl_tasks)) { 758 rpc_killall_tasks(clnt); 759 wait_event_timeout(destroy_wait, 760 list_empty(&clnt->cl_tasks), 1*HZ); 761 } 762 763 rpc_release_client(clnt); 764} 765EXPORT_SYMBOL_GPL(rpc_shutdown_client); 766 767/* 768 * Free an RPC client 769 */ 770static struct rpc_clnt * 771rpc_free_client(struct rpc_clnt *clnt) 772{ 773 struct rpc_clnt *parent = NULL; 774 775 dprintk_rcu("RPC: destroying %s client for %s\n", 776 clnt->cl_program->name, 777 rcu_dereference(clnt->cl_xprt)->servername); 778 if (clnt->cl_parent != clnt) 779 parent = clnt->cl_parent; 780 rpc_clnt_debugfs_unregister(clnt); 781 rpc_clnt_remove_pipedir(clnt); 782 rpc_unregister_client(clnt); 783 rpc_free_iostats(clnt->cl_metrics); 784 clnt->cl_metrics = NULL; 785 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 786 rpciod_down(); 787 rpc_free_clid(clnt); 788 kfree(clnt); 789 return parent; 790} 791 792/* 793 * Free an RPC client 794 */ 795static struct rpc_clnt * 796rpc_free_auth(struct rpc_clnt *clnt) 797{ 798 if (clnt->cl_auth == NULL) 799 return rpc_free_client(clnt); 800 801 /* 802 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 803 * release remaining GSS contexts. This mechanism ensures 804 * that it can do so safely. 805 */ 806 atomic_inc(&clnt->cl_count); 807 rpcauth_release(clnt->cl_auth); 808 clnt->cl_auth = NULL; 809 if (atomic_dec_and_test(&clnt->cl_count)) 810 return rpc_free_client(clnt); 811 return NULL; 812} 813 814/* 815 * Release reference to the RPC client 816 */ 817void 818rpc_release_client(struct rpc_clnt *clnt) 819{ 820 dprintk("RPC: rpc_release_client(%p)\n", clnt); 821 822 do { 823 if (list_empty(&clnt->cl_tasks)) 824 wake_up(&destroy_wait); 825 if (!atomic_dec_and_test(&clnt->cl_count)) 826 break; 827 clnt = rpc_free_auth(clnt); 828 } while (clnt != NULL); 829} 830EXPORT_SYMBOL_GPL(rpc_release_client); 831 832/** 833 * rpc_bind_new_program - bind a new RPC program to an existing client 834 * @old: old rpc_client 835 * @program: rpc program to set 836 * @vers: rpc program version 837 * 838 * Clones the rpc client and sets up a new RPC program. This is mainly 839 * of use for enabling different RPC programs to share the same transport. 840 * The Sun NFSv2/v3 ACL protocol can do this. 841 */ 842struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 843 const struct rpc_program *program, 844 u32 vers) 845{ 846 struct rpc_create_args args = { 847 .program = program, 848 .prognumber = program->number, 849 .version = vers, 850 .authflavor = old->cl_auth->au_flavor, 851 }; 852 struct rpc_clnt *clnt; 853 int err; 854 855 clnt = __rpc_clone_client(&args, old); 856 if (IS_ERR(clnt)) 857 goto out; 858 err = rpc_ping(clnt); 859 if (err != 0) { 860 rpc_shutdown_client(clnt); 861 clnt = ERR_PTR(err); 862 } 863out: 864 return clnt; 865} 866EXPORT_SYMBOL_GPL(rpc_bind_new_program); 867 868void rpc_task_release_client(struct rpc_task *task) 869{ 870 struct rpc_clnt *clnt = task->tk_client; 871 872 if (clnt != NULL) { 873 /* Remove from client task list */ 874 spin_lock(&clnt->cl_lock); 875 list_del(&task->tk_task); 876 spin_unlock(&clnt->cl_lock); 877 task->tk_client = NULL; 878 879 rpc_release_client(clnt); 880 } 881} 882 883static 884void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 885{ 886 if (clnt != NULL) { 887 rpc_task_release_client(task); 888 task->tk_client = clnt; 889 atomic_inc(&clnt->cl_count); 890 if (clnt->cl_softrtry) 891 task->tk_flags |= RPC_TASK_SOFT; 892 if (clnt->cl_noretranstimeo) 893 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 894 if (sk_memalloc_socks()) { 895 struct rpc_xprt *xprt; 896 897 rcu_read_lock(); 898 xprt = rcu_dereference(clnt->cl_xprt); 899 if (xprt->swapper) 900 task->tk_flags |= RPC_TASK_SWAPPER; 901 rcu_read_unlock(); 902 } 903 /* Add to the client's list of all tasks */ 904 spin_lock(&clnt->cl_lock); 905 list_add_tail(&task->tk_task, &clnt->cl_tasks); 906 spin_unlock(&clnt->cl_lock); 907 } 908} 909 910void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt) 911{ 912 rpc_task_release_client(task); 913 rpc_task_set_client(task, clnt); 914} 915EXPORT_SYMBOL_GPL(rpc_task_reset_client); 916 917 918static void 919rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 920{ 921 if (msg != NULL) { 922 task->tk_msg.rpc_proc = msg->rpc_proc; 923 task->tk_msg.rpc_argp = msg->rpc_argp; 924 task->tk_msg.rpc_resp = msg->rpc_resp; 925 if (msg->rpc_cred != NULL) 926 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 927 } 928} 929 930/* 931 * Default callback for async RPC calls 932 */ 933static void 934rpc_default_callback(struct rpc_task *task, void *data) 935{ 936} 937 938static const struct rpc_call_ops rpc_default_ops = { 939 .rpc_call_done = rpc_default_callback, 940}; 941 942/** 943 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 944 * @task_setup_data: pointer to task initialisation data 945 */ 946struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 947{ 948 struct rpc_task *task; 949 950 task = rpc_new_task(task_setup_data); 951 if (IS_ERR(task)) 952 goto out; 953 954 rpc_task_set_client(task, task_setup_data->rpc_client); 955 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 956 957 if (task->tk_action == NULL) 958 rpc_call_start(task); 959 960 atomic_inc(&task->tk_count); 961 rpc_execute(task); 962out: 963 return task; 964} 965EXPORT_SYMBOL_GPL(rpc_run_task); 966 967/** 968 * rpc_call_sync - Perform a synchronous RPC call 969 * @clnt: pointer to RPC client 970 * @msg: RPC call parameters 971 * @flags: RPC call flags 972 */ 973int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 974{ 975 struct rpc_task *task; 976 struct rpc_task_setup task_setup_data = { 977 .rpc_client = clnt, 978 .rpc_message = msg, 979 .callback_ops = &rpc_default_ops, 980 .flags = flags, 981 }; 982 int status; 983 984 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 985 if (flags & RPC_TASK_ASYNC) { 986 rpc_release_calldata(task_setup_data.callback_ops, 987 task_setup_data.callback_data); 988 return -EINVAL; 989 } 990 991 task = rpc_run_task(&task_setup_data); 992 if (IS_ERR(task)) 993 return PTR_ERR(task); 994 status = task->tk_status; 995 rpc_put_task(task); 996 return status; 997} 998EXPORT_SYMBOL_GPL(rpc_call_sync); 999 1000/** 1001 * rpc_call_async - Perform an asynchronous RPC call 1002 * @clnt: pointer to RPC client 1003 * @msg: RPC call parameters 1004 * @flags: RPC call flags 1005 * @tk_ops: RPC call ops 1006 * @data: user call data 1007 */ 1008int 1009rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1010 const struct rpc_call_ops *tk_ops, void *data) 1011{ 1012 struct rpc_task *task; 1013 struct rpc_task_setup task_setup_data = { 1014 .rpc_client = clnt, 1015 .rpc_message = msg, 1016 .callback_ops = tk_ops, 1017 .callback_data = data, 1018 .flags = flags|RPC_TASK_ASYNC, 1019 }; 1020 1021 task = rpc_run_task(&task_setup_data); 1022 if (IS_ERR(task)) 1023 return PTR_ERR(task); 1024 rpc_put_task(task); 1025 return 0; 1026} 1027EXPORT_SYMBOL_GPL(rpc_call_async); 1028 1029#if defined(CONFIG_SUNRPC_BACKCHANNEL) 1030/** 1031 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1032 * rpc_execute against it 1033 * @req: RPC request 1034 * @tk_ops: RPC call ops 1035 */ 1036struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 1037 const struct rpc_call_ops *tk_ops) 1038{ 1039 struct rpc_task *task; 1040 struct xdr_buf *xbufp = &req->rq_snd_buf; 1041 struct rpc_task_setup task_setup_data = { 1042 .callback_ops = tk_ops, 1043 }; 1044 1045 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1046 /* 1047 * Create an rpc_task to send the data 1048 */ 1049 task = rpc_new_task(&task_setup_data); 1050 if (IS_ERR(task)) { 1051 xprt_free_bc_request(req); 1052 goto out; 1053 } 1054 task->tk_rqstp = req; 1055 1056 /* 1057 * Set up the xdr_buf length. 1058 * This also indicates that the buffer is XDR encoded already. 1059 */ 1060 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1061 xbufp->tail[0].iov_len; 1062 1063 task->tk_action = call_bc_transmit; 1064 atomic_inc(&task->tk_count); 1065 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1066 rpc_execute(task); 1067 1068out: 1069 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1070 return task; 1071} 1072#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1073 1074void 1075rpc_call_start(struct rpc_task *task) 1076{ 1077 task->tk_action = call_start; 1078} 1079EXPORT_SYMBOL_GPL(rpc_call_start); 1080 1081/** 1082 * rpc_peeraddr - extract remote peer address from clnt's xprt 1083 * @clnt: RPC client structure 1084 * @buf: target buffer 1085 * @bufsize: length of target buffer 1086 * 1087 * Returns the number of bytes that are actually in the stored address. 1088 */ 1089size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1090{ 1091 size_t bytes; 1092 struct rpc_xprt *xprt; 1093 1094 rcu_read_lock(); 1095 xprt = rcu_dereference(clnt->cl_xprt); 1096 1097 bytes = xprt->addrlen; 1098 if (bytes > bufsize) 1099 bytes = bufsize; 1100 memcpy(buf, &xprt->addr, bytes); 1101 rcu_read_unlock(); 1102 1103 return bytes; 1104} 1105EXPORT_SYMBOL_GPL(rpc_peeraddr); 1106 1107/** 1108 * rpc_peeraddr2str - return remote peer address in printable format 1109 * @clnt: RPC client structure 1110 * @format: address format 1111 * 1112 * NB: the lifetime of the memory referenced by the returned pointer is 1113 * the same as the rpc_xprt itself. As long as the caller uses this 1114 * pointer, it must hold the RCU read lock. 1115 */ 1116const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1117 enum rpc_display_format_t format) 1118{ 1119 struct rpc_xprt *xprt; 1120 1121 xprt = rcu_dereference(clnt->cl_xprt); 1122 1123 if (xprt->address_strings[format] != NULL) 1124 return xprt->address_strings[format]; 1125 else 1126 return "unprintable"; 1127} 1128EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1129 1130static const struct sockaddr_in rpc_inaddr_loopback = { 1131 .sin_family = AF_INET, 1132 .sin_addr.s_addr = htonl(INADDR_ANY), 1133}; 1134 1135static const struct sockaddr_in6 rpc_in6addr_loopback = { 1136 .sin6_family = AF_INET6, 1137 .sin6_addr = IN6ADDR_ANY_INIT, 1138}; 1139 1140/* 1141 * Try a getsockname() on a connected datagram socket. Using a 1142 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1143 * This conserves the ephemeral port number space. 1144 * 1145 * Returns zero and fills in "buf" if successful; otherwise, a 1146 * negative errno is returned. 1147 */ 1148static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1149 struct sockaddr *buf, int buflen) 1150{ 1151 struct socket *sock; 1152 int err; 1153 1154 err = __sock_create(net, sap->sa_family, 1155 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1156 if (err < 0) { 1157 dprintk("RPC: can't create UDP socket (%d)\n", err); 1158 goto out; 1159 } 1160 1161 switch (sap->sa_family) { 1162 case AF_INET: 1163 err = kernel_bind(sock, 1164 (struct sockaddr *)&rpc_inaddr_loopback, 1165 sizeof(rpc_inaddr_loopback)); 1166 break; 1167 case AF_INET6: 1168 err = kernel_bind(sock, 1169 (struct sockaddr *)&rpc_in6addr_loopback, 1170 sizeof(rpc_in6addr_loopback)); 1171 break; 1172 default: 1173 err = -EAFNOSUPPORT; 1174 goto out; 1175 } 1176 if (err < 0) { 1177 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1178 goto out_release; 1179 } 1180 1181 err = kernel_connect(sock, sap, salen, 0); 1182 if (err < 0) { 1183 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1184 goto out_release; 1185 } 1186 1187 err = kernel_getsockname(sock, buf, &buflen); 1188 if (err < 0) { 1189 dprintk("RPC: getsockname failed (%d)\n", err); 1190 goto out_release; 1191 } 1192 1193 err = 0; 1194 if (buf->sa_family == AF_INET6) { 1195 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1196 sin6->sin6_scope_id = 0; 1197 } 1198 dprintk("RPC: %s succeeded\n", __func__); 1199 1200out_release: 1201 sock_release(sock); 1202out: 1203 return err; 1204} 1205 1206/* 1207 * Scraping a connected socket failed, so we don't have a useable 1208 * local address. Fallback: generate an address that will prevent 1209 * the server from calling us back. 1210 * 1211 * Returns zero and fills in "buf" if successful; otherwise, a 1212 * negative errno is returned. 1213 */ 1214static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1215{ 1216 switch (family) { 1217 case AF_INET: 1218 if (buflen < sizeof(rpc_inaddr_loopback)) 1219 return -EINVAL; 1220 memcpy(buf, &rpc_inaddr_loopback, 1221 sizeof(rpc_inaddr_loopback)); 1222 break; 1223 case AF_INET6: 1224 if (buflen < sizeof(rpc_in6addr_loopback)) 1225 return -EINVAL; 1226 memcpy(buf, &rpc_in6addr_loopback, 1227 sizeof(rpc_in6addr_loopback)); 1228 default: 1229 dprintk("RPC: %s: address family not supported\n", 1230 __func__); 1231 return -EAFNOSUPPORT; 1232 } 1233 dprintk("RPC: %s: succeeded\n", __func__); 1234 return 0; 1235} 1236 1237/** 1238 * rpc_localaddr - discover local endpoint address for an RPC client 1239 * @clnt: RPC client structure 1240 * @buf: target buffer 1241 * @buflen: size of target buffer, in bytes 1242 * 1243 * Returns zero and fills in "buf" and "buflen" if successful; 1244 * otherwise, a negative errno is returned. 1245 * 1246 * This works even if the underlying transport is not currently connected, 1247 * or if the upper layer never previously provided a source address. 1248 * 1249 * The result of this function call is transient: multiple calls in 1250 * succession may give different results, depending on how local 1251 * networking configuration changes over time. 1252 */ 1253int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1254{ 1255 struct sockaddr_storage address; 1256 struct sockaddr *sap = (struct sockaddr *)&address; 1257 struct rpc_xprt *xprt; 1258 struct net *net; 1259 size_t salen; 1260 int err; 1261 1262 rcu_read_lock(); 1263 xprt = rcu_dereference(clnt->cl_xprt); 1264 salen = xprt->addrlen; 1265 memcpy(sap, &xprt->addr, salen); 1266 net = get_net(xprt->xprt_net); 1267 rcu_read_unlock(); 1268 1269 rpc_set_port(sap, 0); 1270 err = rpc_sockname(net, sap, salen, buf, buflen); 1271 put_net(net); 1272 if (err != 0) 1273 /* Couldn't discover local address, return ANYADDR */ 1274 return rpc_anyaddr(sap->sa_family, buf, buflen); 1275 return 0; 1276} 1277EXPORT_SYMBOL_GPL(rpc_localaddr); 1278 1279void 1280rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1281{ 1282 struct rpc_xprt *xprt; 1283 1284 rcu_read_lock(); 1285 xprt = rcu_dereference(clnt->cl_xprt); 1286 if (xprt->ops->set_buffer_size) 1287 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1288 rcu_read_unlock(); 1289} 1290EXPORT_SYMBOL_GPL(rpc_setbufsize); 1291 1292/** 1293 * rpc_protocol - Get transport protocol number for an RPC client 1294 * @clnt: RPC client to query 1295 * 1296 */ 1297int rpc_protocol(struct rpc_clnt *clnt) 1298{ 1299 int protocol; 1300 1301 rcu_read_lock(); 1302 protocol = rcu_dereference(clnt->cl_xprt)->prot; 1303 rcu_read_unlock(); 1304 return protocol; 1305} 1306EXPORT_SYMBOL_GPL(rpc_protocol); 1307 1308/** 1309 * rpc_net_ns - Get the network namespace for this RPC client 1310 * @clnt: RPC client to query 1311 * 1312 */ 1313struct net *rpc_net_ns(struct rpc_clnt *clnt) 1314{ 1315 struct net *ret; 1316 1317 rcu_read_lock(); 1318 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1319 rcu_read_unlock(); 1320 return ret; 1321} 1322EXPORT_SYMBOL_GPL(rpc_net_ns); 1323 1324/** 1325 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1326 * @clnt: RPC client to query 1327 * 1328 * For stream transports, this is one RPC record fragment (see RFC 1329 * 1831), as we don't support multi-record requests yet. For datagram 1330 * transports, this is the size of an IP packet minus the IP, UDP, and 1331 * RPC header sizes. 1332 */ 1333size_t rpc_max_payload(struct rpc_clnt *clnt) 1334{ 1335 size_t ret; 1336 1337 rcu_read_lock(); 1338 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1339 rcu_read_unlock(); 1340 return ret; 1341} 1342EXPORT_SYMBOL_GPL(rpc_max_payload); 1343 1344/** 1345 * rpc_get_timeout - Get timeout for transport in units of HZ 1346 * @clnt: RPC client to query 1347 */ 1348unsigned long rpc_get_timeout(struct rpc_clnt *clnt) 1349{ 1350 unsigned long ret; 1351 1352 rcu_read_lock(); 1353 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval; 1354 rcu_read_unlock(); 1355 return ret; 1356} 1357EXPORT_SYMBOL_GPL(rpc_get_timeout); 1358 1359/** 1360 * rpc_force_rebind - force transport to check that remote port is unchanged 1361 * @clnt: client to rebind 1362 * 1363 */ 1364void rpc_force_rebind(struct rpc_clnt *clnt) 1365{ 1366 if (clnt->cl_autobind) { 1367 rcu_read_lock(); 1368 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1369 rcu_read_unlock(); 1370 } 1371} 1372EXPORT_SYMBOL_GPL(rpc_force_rebind); 1373 1374/* 1375 * Restart an (async) RPC call from the call_prepare state. 1376 * Usually called from within the exit handler. 1377 */ 1378int 1379rpc_restart_call_prepare(struct rpc_task *task) 1380{ 1381 if (RPC_ASSASSINATED(task)) 1382 return 0; 1383 task->tk_action = call_start; 1384 task->tk_status = 0; 1385 if (task->tk_ops->rpc_call_prepare != NULL) 1386 task->tk_action = rpc_prepare_task; 1387 return 1; 1388} 1389EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1390 1391/* 1392 * Restart an (async) RPC call. Usually called from within the 1393 * exit handler. 1394 */ 1395int 1396rpc_restart_call(struct rpc_task *task) 1397{ 1398 if (RPC_ASSASSINATED(task)) 1399 return 0; 1400 task->tk_action = call_start; 1401 task->tk_status = 0; 1402 return 1; 1403} 1404EXPORT_SYMBOL_GPL(rpc_restart_call); 1405 1406#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 1407const char 1408*rpc_proc_name(const struct rpc_task *task) 1409{ 1410 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1411 1412 if (proc) { 1413 if (proc->p_name) 1414 return proc->p_name; 1415 else 1416 return "NULL"; 1417 } else 1418 return "no proc"; 1419} 1420#endif 1421 1422/* 1423 * 0. Initial state 1424 * 1425 * Other FSM states can be visited zero or more times, but 1426 * this state is visited exactly once for each RPC. 1427 */ 1428static void 1429call_start(struct rpc_task *task) 1430{ 1431 struct rpc_clnt *clnt = task->tk_client; 1432 1433 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 1434 clnt->cl_program->name, clnt->cl_vers, 1435 rpc_proc_name(task), 1436 (RPC_IS_ASYNC(task) ? "async" : "sync")); 1437 1438 /* Increment call count */ 1439 task->tk_msg.rpc_proc->p_count++; 1440 clnt->cl_stats->rpccnt++; 1441 task->tk_action = call_reserve; 1442} 1443 1444/* 1445 * 1. Reserve an RPC call slot 1446 */ 1447static void 1448call_reserve(struct rpc_task *task) 1449{ 1450 dprint_status(task); 1451 1452 task->tk_status = 0; 1453 task->tk_action = call_reserveresult; 1454 xprt_reserve(task); 1455} 1456 1457static void call_retry_reserve(struct rpc_task *task); 1458 1459/* 1460 * 1b. Grok the result of xprt_reserve() 1461 */ 1462static void 1463call_reserveresult(struct rpc_task *task) 1464{ 1465 int status = task->tk_status; 1466 1467 dprint_status(task); 1468 1469 /* 1470 * After a call to xprt_reserve(), we must have either 1471 * a request slot or else an error status. 1472 */ 1473 task->tk_status = 0; 1474 if (status >= 0) { 1475 if (task->tk_rqstp) { 1476 task->tk_action = call_refresh; 1477 return; 1478 } 1479 1480 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1481 __func__, status); 1482 rpc_exit(task, -EIO); 1483 return; 1484 } 1485 1486 /* 1487 * Even though there was an error, we may have acquired 1488 * a request slot somehow. Make sure not to leak it. 1489 */ 1490 if (task->tk_rqstp) { 1491 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1492 __func__, status); 1493 xprt_release(task); 1494 } 1495 1496 switch (status) { 1497 case -ENOMEM: 1498 rpc_delay(task, HZ >> 2); 1499 case -EAGAIN: /* woken up; retry */ 1500 task->tk_action = call_retry_reserve; 1501 return; 1502 case -EIO: /* probably a shutdown */ 1503 break; 1504 default: 1505 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1506 __func__, status); 1507 break; 1508 } 1509 rpc_exit(task, status); 1510} 1511 1512/* 1513 * 1c. Retry reserving an RPC call slot 1514 */ 1515static void 1516call_retry_reserve(struct rpc_task *task) 1517{ 1518 dprint_status(task); 1519 1520 task->tk_status = 0; 1521 task->tk_action = call_reserveresult; 1522 xprt_retry_reserve(task); 1523} 1524 1525/* 1526 * 2. Bind and/or refresh the credentials 1527 */ 1528static void 1529call_refresh(struct rpc_task *task) 1530{ 1531 dprint_status(task); 1532 1533 task->tk_action = call_refreshresult; 1534 task->tk_status = 0; 1535 task->tk_client->cl_stats->rpcauthrefresh++; 1536 rpcauth_refreshcred(task); 1537} 1538 1539/* 1540 * 2a. Process the results of a credential refresh 1541 */ 1542static void 1543call_refreshresult(struct rpc_task *task) 1544{ 1545 int status = task->tk_status; 1546 1547 dprint_status(task); 1548 1549 task->tk_status = 0; 1550 task->tk_action = call_refresh; 1551 switch (status) { 1552 case 0: 1553 if (rpcauth_uptodatecred(task)) { 1554 task->tk_action = call_allocate; 1555 return; 1556 } 1557 /* Use rate-limiting and a max number of retries if refresh 1558 * had status 0 but failed to update the cred. 1559 */ 1560 case -ETIMEDOUT: 1561 rpc_delay(task, 3*HZ); 1562 case -EAGAIN: 1563 status = -EACCES; 1564 case -EKEYEXPIRED: 1565 if (!task->tk_cred_retry) 1566 break; 1567 task->tk_cred_retry--; 1568 dprintk("RPC: %5u %s: retry refresh creds\n", 1569 task->tk_pid, __func__); 1570 return; 1571 } 1572 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1573 task->tk_pid, __func__, status); 1574 rpc_exit(task, status); 1575} 1576 1577/* 1578 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1579 * (Note: buffer memory is freed in xprt_release). 1580 */ 1581static void 1582call_allocate(struct rpc_task *task) 1583{ 1584 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1585 struct rpc_rqst *req = task->tk_rqstp; 1586 struct rpc_xprt *xprt = req->rq_xprt; 1587 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1588 1589 dprint_status(task); 1590 1591 task->tk_status = 0; 1592 task->tk_action = call_bind; 1593 1594 if (req->rq_buffer) 1595 return; 1596 1597 if (proc->p_proc != 0) { 1598 BUG_ON(proc->p_arglen == 0); 1599 if (proc->p_decode != NULL) 1600 BUG_ON(proc->p_replen == 0); 1601 } 1602 1603 /* 1604 * Calculate the size (in quads) of the RPC call 1605 * and reply headers, and convert both values 1606 * to byte sizes. 1607 */ 1608 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1609 req->rq_callsize <<= 2; 1610 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1611 req->rq_rcvsize <<= 2; 1612 1613 req->rq_buffer = xprt->ops->buf_alloc(task, 1614 req->rq_callsize + req->rq_rcvsize); 1615 if (req->rq_buffer != NULL) 1616 return; 1617 1618 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1619 1620 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1621 task->tk_action = call_allocate; 1622 rpc_delay(task, HZ>>4); 1623 return; 1624 } 1625 1626 rpc_exit(task, -ERESTARTSYS); 1627} 1628 1629static inline int 1630rpc_task_need_encode(struct rpc_task *task) 1631{ 1632 return task->tk_rqstp->rq_snd_buf.len == 0; 1633} 1634 1635static inline void 1636rpc_task_force_reencode(struct rpc_task *task) 1637{ 1638 task->tk_rqstp->rq_snd_buf.len = 0; 1639 task->tk_rqstp->rq_bytes_sent = 0; 1640} 1641 1642static inline void 1643rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1644{ 1645 buf->head[0].iov_base = start; 1646 buf->head[0].iov_len = len; 1647 buf->tail[0].iov_len = 0; 1648 buf->page_len = 0; 1649 buf->flags = 0; 1650 buf->len = 0; 1651 buf->buflen = len; 1652} 1653 1654/* 1655 * 3. Encode arguments of an RPC call 1656 */ 1657static void 1658rpc_xdr_encode(struct rpc_task *task) 1659{ 1660 struct rpc_rqst *req = task->tk_rqstp; 1661 kxdreproc_t encode; 1662 __be32 *p; 1663 1664 dprint_status(task); 1665 1666 rpc_xdr_buf_init(&req->rq_snd_buf, 1667 req->rq_buffer, 1668 req->rq_callsize); 1669 rpc_xdr_buf_init(&req->rq_rcv_buf, 1670 (char *)req->rq_buffer + req->rq_callsize, 1671 req->rq_rcvsize); 1672 1673 p = rpc_encode_header(task); 1674 if (p == NULL) { 1675 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1676 rpc_exit(task, -EIO); 1677 return; 1678 } 1679 1680 encode = task->tk_msg.rpc_proc->p_encode; 1681 if (encode == NULL) 1682 return; 1683 1684 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1685 task->tk_msg.rpc_argp); 1686} 1687 1688/* 1689 * 4. Get the server port number if not yet set 1690 */ 1691static void 1692call_bind(struct rpc_task *task) 1693{ 1694 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1695 1696 dprint_status(task); 1697 1698 task->tk_action = call_connect; 1699 if (!xprt_bound(xprt)) { 1700 task->tk_action = call_bind_status; 1701 task->tk_timeout = xprt->bind_timeout; 1702 xprt->ops->rpcbind(task); 1703 } 1704} 1705 1706/* 1707 * 4a. Sort out bind result 1708 */ 1709static void 1710call_bind_status(struct rpc_task *task) 1711{ 1712 int status = -EIO; 1713 1714 if (task->tk_status >= 0) { 1715 dprint_status(task); 1716 task->tk_status = 0; 1717 task->tk_action = call_connect; 1718 return; 1719 } 1720 1721 trace_rpc_bind_status(task); 1722 switch (task->tk_status) { 1723 case -ENOMEM: 1724 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1725 rpc_delay(task, HZ >> 2); 1726 goto retry_timeout; 1727 case -EACCES: 1728 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1729 "unavailable\n", task->tk_pid); 1730 /* fail immediately if this is an RPC ping */ 1731 if (task->tk_msg.rpc_proc->p_proc == 0) { 1732 status = -EOPNOTSUPP; 1733 break; 1734 } 1735 if (task->tk_rebind_retry == 0) 1736 break; 1737 task->tk_rebind_retry--; 1738 rpc_delay(task, 3*HZ); 1739 goto retry_timeout; 1740 case -ETIMEDOUT: 1741 dprintk("RPC: %5u rpcbind request timed out\n", 1742 task->tk_pid); 1743 goto retry_timeout; 1744 case -EPFNOSUPPORT: 1745 /* server doesn't support any rpcbind version we know of */ 1746 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1747 task->tk_pid); 1748 break; 1749 case -EPROTONOSUPPORT: 1750 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1751 task->tk_pid); 1752 goto retry_timeout; 1753 case -ECONNREFUSED: /* connection problems */ 1754 case -ECONNRESET: 1755 case -ECONNABORTED: 1756 case -ENOTCONN: 1757 case -EHOSTDOWN: 1758 case -EHOSTUNREACH: 1759 case -ENETUNREACH: 1760 case -ENOBUFS: 1761 case -EPIPE: 1762 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1763 task->tk_pid, task->tk_status); 1764 if (!RPC_IS_SOFTCONN(task)) { 1765 rpc_delay(task, 5*HZ); 1766 goto retry_timeout; 1767 } 1768 status = task->tk_status; 1769 break; 1770 default: 1771 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1772 task->tk_pid, -task->tk_status); 1773 } 1774 1775 rpc_exit(task, status); 1776 return; 1777 1778retry_timeout: 1779 task->tk_status = 0; 1780 task->tk_action = call_timeout; 1781} 1782 1783/* 1784 * 4b. Connect to the RPC server 1785 */ 1786static void 1787call_connect(struct rpc_task *task) 1788{ 1789 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1790 1791 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1792 task->tk_pid, xprt, 1793 (xprt_connected(xprt) ? "is" : "is not")); 1794 1795 task->tk_action = call_transmit; 1796 if (!xprt_connected(xprt)) { 1797 task->tk_action = call_connect_status; 1798 if (task->tk_status < 0) 1799 return; 1800 if (task->tk_flags & RPC_TASK_NOCONNECT) { 1801 rpc_exit(task, -ENOTCONN); 1802 return; 1803 } 1804 xprt_connect(task); 1805 } 1806} 1807 1808/* 1809 * 4c. Sort out connect result 1810 */ 1811static void 1812call_connect_status(struct rpc_task *task) 1813{ 1814 struct rpc_clnt *clnt = task->tk_client; 1815 int status = task->tk_status; 1816 1817 dprint_status(task); 1818 1819 trace_rpc_connect_status(task, status); 1820 task->tk_status = 0; 1821 switch (status) { 1822 case -ECONNREFUSED: 1823 case -ECONNRESET: 1824 case -ECONNABORTED: 1825 case -ENETUNREACH: 1826 case -EHOSTUNREACH: 1827 case -EADDRINUSE: 1828 case -ENOBUFS: 1829 case -EPIPE: 1830 if (RPC_IS_SOFTCONN(task)) 1831 break; 1832 /* retry with existing socket, after a delay */ 1833 rpc_delay(task, 3*HZ); 1834 case -EAGAIN: 1835 /* Check for timeouts before looping back to call_bind */ 1836 case -ETIMEDOUT: 1837 task->tk_action = call_timeout; 1838 return; 1839 case 0: 1840 clnt->cl_stats->netreconn++; 1841 task->tk_action = call_transmit; 1842 return; 1843 } 1844 rpc_exit(task, status); 1845} 1846 1847/* 1848 * 5. Transmit the RPC request, and wait for reply 1849 */ 1850static void 1851call_transmit(struct rpc_task *task) 1852{ 1853 int is_retrans = RPC_WAS_SENT(task); 1854 1855 dprint_status(task); 1856 1857 task->tk_action = call_status; 1858 if (task->tk_status < 0) 1859 return; 1860 if (!xprt_prepare_transmit(task)) 1861 return; 1862 task->tk_action = call_transmit_status; 1863 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1864 if (rpc_task_need_encode(task)) { 1865 rpc_xdr_encode(task); 1866 /* Did the encode result in an error condition? */ 1867 if (task->tk_status != 0) { 1868 /* Was the error nonfatal? */ 1869 if (task->tk_status == -EAGAIN) 1870 rpc_delay(task, HZ >> 4); 1871 else 1872 rpc_exit(task, task->tk_status); 1873 return; 1874 } 1875 } 1876 xprt_transmit(task); 1877 if (task->tk_status < 0) 1878 return; 1879 if (is_retrans) 1880 task->tk_client->cl_stats->rpcretrans++; 1881 /* 1882 * On success, ensure that we call xprt_end_transmit() before sleeping 1883 * in order to allow access to the socket to other RPC requests. 1884 */ 1885 call_transmit_status(task); 1886 if (rpc_reply_expected(task)) 1887 return; 1888 task->tk_action = rpc_exit_task; 1889 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task); 1890} 1891 1892/* 1893 * 5a. Handle cleanup after a transmission 1894 */ 1895static void 1896call_transmit_status(struct rpc_task *task) 1897{ 1898 task->tk_action = call_status; 1899 1900 /* 1901 * Common case: success. Force the compiler to put this 1902 * test first. 1903 */ 1904 if (task->tk_status == 0) { 1905 xprt_end_transmit(task); 1906 rpc_task_force_reencode(task); 1907 return; 1908 } 1909 1910 switch (task->tk_status) { 1911 case -EAGAIN: 1912 break; 1913 default: 1914 dprint_status(task); 1915 xprt_end_transmit(task); 1916 rpc_task_force_reencode(task); 1917 break; 1918 /* 1919 * Special cases: if we've been waiting on the 1920 * socket's write_space() callback, or if the 1921 * socket just returned a connection error, 1922 * then hold onto the transport lock. 1923 */ 1924 case -ECONNREFUSED: 1925 case -EHOSTDOWN: 1926 case -EHOSTUNREACH: 1927 case -ENETUNREACH: 1928 case -EPERM: 1929 if (RPC_IS_SOFTCONN(task)) { 1930 xprt_end_transmit(task); 1931 rpc_exit(task, task->tk_status); 1932 break; 1933 } 1934 case -ECONNRESET: 1935 case -ECONNABORTED: 1936 case -EADDRINUSE: 1937 case -ENOTCONN: 1938 case -ENOBUFS: 1939 case -EPIPE: 1940 rpc_task_force_reencode(task); 1941 } 1942} 1943 1944#if defined(CONFIG_SUNRPC_BACKCHANNEL) 1945/* 1946 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 1947 * addition, disconnect on connectivity errors. 1948 */ 1949static void 1950call_bc_transmit(struct rpc_task *task) 1951{ 1952 struct rpc_rqst *req = task->tk_rqstp; 1953 1954 if (!xprt_prepare_transmit(task)) { 1955 /* 1956 * Could not reserve the transport. Try again after the 1957 * transport is released. 1958 */ 1959 task->tk_status = 0; 1960 task->tk_action = call_bc_transmit; 1961 return; 1962 } 1963 1964 task->tk_action = rpc_exit_task; 1965 if (task->tk_status < 0) { 1966 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1967 "error: %d\n", task->tk_status); 1968 return; 1969 } 1970 1971 xprt_transmit(task); 1972 xprt_end_transmit(task); 1973 dprint_status(task); 1974 switch (task->tk_status) { 1975 case 0: 1976 /* Success */ 1977 break; 1978 case -EHOSTDOWN: 1979 case -EHOSTUNREACH: 1980 case -ENETUNREACH: 1981 case -ETIMEDOUT: 1982 /* 1983 * Problem reaching the server. Disconnect and let the 1984 * forechannel reestablish the connection. The server will 1985 * have to retransmit the backchannel request and we'll 1986 * reprocess it. Since these ops are idempotent, there's no 1987 * need to cache our reply at this time. 1988 */ 1989 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 1990 "error: %d\n", task->tk_status); 1991 xprt_conditional_disconnect(req->rq_xprt, 1992 req->rq_connect_cookie); 1993 break; 1994 default: 1995 /* 1996 * We were unable to reply and will have to drop the 1997 * request. The server should reconnect and retransmit. 1998 */ 1999 WARN_ON_ONCE(task->tk_status == -EAGAIN); 2000 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2001 "error: %d\n", task->tk_status); 2002 break; 2003 } 2004 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 2005} 2006#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2007 2008/* 2009 * 6. Sort out the RPC call status 2010 */ 2011static void 2012call_status(struct rpc_task *task) 2013{ 2014 struct rpc_clnt *clnt = task->tk_client; 2015 struct rpc_rqst *req = task->tk_rqstp; 2016 int status; 2017 2018 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 2019 task->tk_status = req->rq_reply_bytes_recvd; 2020 2021 dprint_status(task); 2022 2023 status = task->tk_status; 2024 if (status >= 0) { 2025 task->tk_action = call_decode; 2026 return; 2027 } 2028 2029 trace_rpc_call_status(task); 2030 task->tk_status = 0; 2031 switch(status) { 2032 case -EHOSTDOWN: 2033 case -EHOSTUNREACH: 2034 case -ENETUNREACH: 2035 case -EPERM: 2036 if (RPC_IS_SOFTCONN(task)) { 2037 rpc_exit(task, status); 2038 break; 2039 } 2040 /* 2041 * Delay any retries for 3 seconds, then handle as if it 2042 * were a timeout. 2043 */ 2044 rpc_delay(task, 3*HZ); 2045 case -ETIMEDOUT: 2046 task->tk_action = call_timeout; 2047 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) 2048 && task->tk_client->cl_discrtry) 2049 xprt_conditional_disconnect(req->rq_xprt, 2050 req->rq_connect_cookie); 2051 break; 2052 case -ECONNREFUSED: 2053 case -ECONNRESET: 2054 case -ECONNABORTED: 2055 rpc_force_rebind(clnt); 2056 case -EADDRINUSE: 2057 case -ENOBUFS: 2058 rpc_delay(task, 3*HZ); 2059 case -EPIPE: 2060 case -ENOTCONN: 2061 task->tk_action = call_bind; 2062 break; 2063 case -EAGAIN: 2064 task->tk_action = call_transmit; 2065 break; 2066 case -EIO: 2067 /* shutdown or soft timeout */ 2068 rpc_exit(task, status); 2069 break; 2070 default: 2071 if (clnt->cl_chatty) 2072 printk("%s: RPC call returned error %d\n", 2073 clnt->cl_program->name, -status); 2074 rpc_exit(task, status); 2075 } 2076} 2077 2078/* 2079 * 6a. Handle RPC timeout 2080 * We do not release the request slot, so we keep using the 2081 * same XID for all retransmits. 2082 */ 2083static void 2084call_timeout(struct rpc_task *task) 2085{ 2086 struct rpc_clnt *clnt = task->tk_client; 2087 2088 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 2089 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 2090 goto retry; 2091 } 2092 2093 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 2094 task->tk_timeouts++; 2095 2096 if (RPC_IS_SOFTCONN(task)) { 2097 rpc_exit(task, -ETIMEDOUT); 2098 return; 2099 } 2100 if (RPC_IS_SOFT(task)) { 2101 if (clnt->cl_chatty) { 2102 rcu_read_lock(); 2103 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 2104 clnt->cl_program->name, 2105 rcu_dereference(clnt->cl_xprt)->servername); 2106 rcu_read_unlock(); 2107 } 2108 if (task->tk_flags & RPC_TASK_TIMEOUT) 2109 rpc_exit(task, -ETIMEDOUT); 2110 else 2111 rpc_exit(task, -EIO); 2112 return; 2113 } 2114 2115 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2116 task->tk_flags |= RPC_CALL_MAJORSEEN; 2117 if (clnt->cl_chatty) { 2118 rcu_read_lock(); 2119 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 2120 clnt->cl_program->name, 2121 rcu_dereference(clnt->cl_xprt)->servername); 2122 rcu_read_unlock(); 2123 } 2124 } 2125 rpc_force_rebind(clnt); 2126 /* 2127 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2128 * event? RFC2203 requires the server to drop all such requests. 2129 */ 2130 rpcauth_invalcred(task); 2131 2132retry: 2133 task->tk_action = call_bind; 2134 task->tk_status = 0; 2135} 2136 2137/* 2138 * 7. Decode the RPC reply 2139 */ 2140static void 2141call_decode(struct rpc_task *task) 2142{ 2143 struct rpc_clnt *clnt = task->tk_client; 2144 struct rpc_rqst *req = task->tk_rqstp; 2145 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 2146 __be32 *p; 2147 2148 dprint_status(task); 2149 2150 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2151 if (clnt->cl_chatty) { 2152 rcu_read_lock(); 2153 printk(KERN_NOTICE "%s: server %s OK\n", 2154 clnt->cl_program->name, 2155 rcu_dereference(clnt->cl_xprt)->servername); 2156 rcu_read_unlock(); 2157 } 2158 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2159 } 2160 2161 /* 2162 * Ensure that we see all writes made by xprt_complete_rqst() 2163 * before it changed req->rq_reply_bytes_recvd. 2164 */ 2165 smp_rmb(); 2166 req->rq_rcv_buf.len = req->rq_private_buf.len; 2167 2168 /* Check that the softirq receive buffer is valid */ 2169 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2170 sizeof(req->rq_rcv_buf)) != 0); 2171 2172 if (req->rq_rcv_buf.len < 12) { 2173 if (!RPC_IS_SOFT(task)) { 2174 task->tk_action = call_bind; 2175 goto out_retry; 2176 } 2177 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 2178 clnt->cl_program->name, task->tk_status); 2179 task->tk_action = call_timeout; 2180 goto out_retry; 2181 } 2182 2183 p = rpc_verify_header(task); 2184 if (IS_ERR(p)) { 2185 if (p == ERR_PTR(-EAGAIN)) 2186 goto out_retry; 2187 return; 2188 } 2189 2190 task->tk_action = rpc_exit_task; 2191 2192 if (decode) { 2193 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 2194 task->tk_msg.rpc_resp); 2195 } 2196 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 2197 task->tk_status); 2198 return; 2199out_retry: 2200 task->tk_status = 0; 2201 /* Note: rpc_verify_header() may have freed the RPC slot */ 2202 if (task->tk_rqstp == req) { 2203 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 2204 if (task->tk_client->cl_discrtry) 2205 xprt_conditional_disconnect(req->rq_xprt, 2206 req->rq_connect_cookie); 2207 } 2208} 2209 2210static __be32 * 2211rpc_encode_header(struct rpc_task *task) 2212{ 2213 struct rpc_clnt *clnt = task->tk_client; 2214 struct rpc_rqst *req = task->tk_rqstp; 2215 __be32 *p = req->rq_svec[0].iov_base; 2216 2217 /* FIXME: check buffer size? */ 2218 2219 p = xprt_skip_transport_header(req->rq_xprt, p); 2220 *p++ = req->rq_xid; /* XID */ 2221 *p++ = htonl(RPC_CALL); /* CALL */ 2222 *p++ = htonl(RPC_VERSION); /* RPC version */ 2223 *p++ = htonl(clnt->cl_prog); /* program number */ 2224 *p++ = htonl(clnt->cl_vers); /* program version */ 2225 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 2226 p = rpcauth_marshcred(task, p); 2227 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 2228 return p; 2229} 2230 2231static __be32 * 2232rpc_verify_header(struct rpc_task *task) 2233{ 2234 struct rpc_clnt *clnt = task->tk_client; 2235 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 2236 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 2237 __be32 *p = iov->iov_base; 2238 u32 n; 2239 int error = -EACCES; 2240 2241 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 2242 /* RFC-1014 says that the representation of XDR data must be a 2243 * multiple of four bytes 2244 * - if it isn't pointer subtraction in the NFS client may give 2245 * undefined results 2246 */ 2247 dprintk("RPC: %5u %s: XDR representation not a multiple of" 2248 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 2249 task->tk_rqstp->rq_rcv_buf.len); 2250 error = -EIO; 2251 goto out_err; 2252 } 2253 if ((len -= 3) < 0) 2254 goto out_overflow; 2255 2256 p += 1; /* skip XID */ 2257 if ((n = ntohl(*p++)) != RPC_REPLY) { 2258 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 2259 task->tk_pid, __func__, n); 2260 error = -EIO; 2261 goto out_garbage; 2262 } 2263 2264 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 2265 if (--len < 0) 2266 goto out_overflow; 2267 switch ((n = ntohl(*p++))) { 2268 case RPC_AUTH_ERROR: 2269 break; 2270 case RPC_MISMATCH: 2271 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 2272 task->tk_pid, __func__); 2273 error = -EPROTONOSUPPORT; 2274 goto out_err; 2275 default: 2276 dprintk("RPC: %5u %s: RPC call rejected, " 2277 "unknown error: %x\n", 2278 task->tk_pid, __func__, n); 2279 error = -EIO; 2280 goto out_err; 2281 } 2282 if (--len < 0) 2283 goto out_overflow; 2284 switch ((n = ntohl(*p++))) { 2285 case RPC_AUTH_REJECTEDCRED: 2286 case RPC_AUTH_REJECTEDVERF: 2287 case RPCSEC_GSS_CREDPROBLEM: 2288 case RPCSEC_GSS_CTXPROBLEM: 2289 if (!task->tk_cred_retry) 2290 break; 2291 task->tk_cred_retry--; 2292 dprintk("RPC: %5u %s: retry stale creds\n", 2293 task->tk_pid, __func__); 2294 rpcauth_invalcred(task); 2295 /* Ensure we obtain a new XID! */ 2296 xprt_release(task); 2297 task->tk_action = call_reserve; 2298 goto out_retry; 2299 case RPC_AUTH_BADCRED: 2300 case RPC_AUTH_BADVERF: 2301 /* possibly garbled cred/verf? */ 2302 if (!task->tk_garb_retry) 2303 break; 2304 task->tk_garb_retry--; 2305 dprintk("RPC: %5u %s: retry garbled creds\n", 2306 task->tk_pid, __func__); 2307 task->tk_action = call_bind; 2308 goto out_retry; 2309 case RPC_AUTH_TOOWEAK: 2310 rcu_read_lock(); 2311 printk(KERN_NOTICE "RPC: server %s requires stronger " 2312 "authentication.\n", 2313 rcu_dereference(clnt->cl_xprt)->servername); 2314 rcu_read_unlock(); 2315 break; 2316 default: 2317 dprintk("RPC: %5u %s: unknown auth error: %x\n", 2318 task->tk_pid, __func__, n); 2319 error = -EIO; 2320 } 2321 dprintk("RPC: %5u %s: call rejected %d\n", 2322 task->tk_pid, __func__, n); 2323 goto out_err; 2324 } 2325 p = rpcauth_checkverf(task, p); 2326 if (IS_ERR(p)) { 2327 error = PTR_ERR(p); 2328 dprintk("RPC: %5u %s: auth check failed with %d\n", 2329 task->tk_pid, __func__, error); 2330 goto out_garbage; /* bad verifier, retry */ 2331 } 2332 len = p - (__be32 *)iov->iov_base - 1; 2333 if (len < 0) 2334 goto out_overflow; 2335 switch ((n = ntohl(*p++))) { 2336 case RPC_SUCCESS: 2337 return p; 2338 case RPC_PROG_UNAVAIL: 2339 dprintk_rcu("RPC: %5u %s: program %u is unsupported " 2340 "by server %s\n", task->tk_pid, __func__, 2341 (unsigned int)clnt->cl_prog, 2342 rcu_dereference(clnt->cl_xprt)->servername); 2343 error = -EPFNOSUPPORT; 2344 goto out_err; 2345 case RPC_PROG_MISMATCH: 2346 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported " 2347 "by server %s\n", task->tk_pid, __func__, 2348 (unsigned int)clnt->cl_prog, 2349 (unsigned int)clnt->cl_vers, 2350 rcu_dereference(clnt->cl_xprt)->servername); 2351 error = -EPROTONOSUPPORT; 2352 goto out_err; 2353 case RPC_PROC_UNAVAIL: 2354 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, " 2355 "version %u on server %s\n", 2356 task->tk_pid, __func__, 2357 rpc_proc_name(task), 2358 clnt->cl_prog, clnt->cl_vers, 2359 rcu_dereference(clnt->cl_xprt)->servername); 2360 error = -EOPNOTSUPP; 2361 goto out_err; 2362 case RPC_GARBAGE_ARGS: 2363 dprintk("RPC: %5u %s: server saw garbage\n", 2364 task->tk_pid, __func__); 2365 break; /* retry */ 2366 default: 2367 dprintk("RPC: %5u %s: server accept status: %x\n", 2368 task->tk_pid, __func__, n); 2369 /* Also retry */ 2370 } 2371 2372out_garbage: 2373 clnt->cl_stats->rpcgarbage++; 2374 if (task->tk_garb_retry) { 2375 task->tk_garb_retry--; 2376 dprintk("RPC: %5u %s: retrying\n", 2377 task->tk_pid, __func__); 2378 task->tk_action = call_bind; 2379out_retry: 2380 return ERR_PTR(-EAGAIN); 2381 } 2382out_err: 2383 rpc_exit(task, error); 2384 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 2385 __func__, error); 2386 return ERR_PTR(error); 2387out_overflow: 2388 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 2389 __func__); 2390 goto out_garbage; 2391} 2392 2393static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2394{ 2395} 2396 2397static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2398{ 2399 return 0; 2400} 2401 2402static struct rpc_procinfo rpcproc_null = { 2403 .p_encode = rpcproc_encode_null, 2404 .p_decode = rpcproc_decode_null, 2405}; 2406 2407static int rpc_ping(struct rpc_clnt *clnt) 2408{ 2409 struct rpc_message msg = { 2410 .rpc_proc = &rpcproc_null, 2411 }; 2412 int err; 2413 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2414 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 2415 put_rpccred(msg.rpc_cred); 2416 return err; 2417} 2418 2419struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2420{ 2421 struct rpc_message msg = { 2422 .rpc_proc = &rpcproc_null, 2423 .rpc_cred = cred, 2424 }; 2425 struct rpc_task_setup task_setup_data = { 2426 .rpc_client = clnt, 2427 .rpc_message = &msg, 2428 .callback_ops = &rpc_default_ops, 2429 .flags = flags, 2430 }; 2431 return rpc_run_task(&task_setup_data); 2432} 2433EXPORT_SYMBOL_GPL(rpc_call_null); 2434 2435#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 2436static void rpc_show_header(void) 2437{ 2438 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 2439 "-timeout ---ops--\n"); 2440} 2441 2442static void rpc_show_task(const struct rpc_clnt *clnt, 2443 const struct rpc_task *task) 2444{ 2445 const char *rpc_waitq = "none"; 2446 2447 if (RPC_IS_QUEUED(task)) 2448 rpc_waitq = rpc_qname(task->tk_waitqueue); 2449 2450 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 2451 task->tk_pid, task->tk_flags, task->tk_status, 2452 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 2453 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 2454 task->tk_action, rpc_waitq); 2455} 2456 2457void rpc_show_tasks(struct net *net) 2458{ 2459 struct rpc_clnt *clnt; 2460 struct rpc_task *task; 2461 int header = 0; 2462 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 2463 2464 spin_lock(&sn->rpc_client_lock); 2465 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 2466 spin_lock(&clnt->cl_lock); 2467 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 2468 if (!header) { 2469 rpc_show_header(); 2470 header++; 2471 } 2472 rpc_show_task(clnt, task); 2473 } 2474 spin_unlock(&clnt->cl_lock); 2475 } 2476 spin_unlock(&sn->rpc_client_lock); 2477} 2478#endif 2479