1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/net/sunrpc/clnt.c 4 * 5 * This file contains the high-level RPC interface. 6 * It is modeled as a finite state machine to support both synchronous 7 * and asynchronous requests. 8 * 9 * - RPC header generation and argument serialization. 10 * - Credential refresh. 11 * - TCP connect handling. 12 * - Retry of operation when it is suspected the operation failed because 13 * of uid squashing on the server, or when the credentials were stale 14 * and need to be refreshed, or when a packet was damaged in transit. 15 * This may be have to be moved to the VFS layer. 16 * 17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 19 */ 20 21 22 #include <linux/module.h> 23 #include <linux/types.h> 24 #include <linux/kallsyms.h> 25 #include <linux/mm.h> 26 #include <linux/namei.h> 27 #include <linux/mount.h> 28 #include <linux/slab.h> 29 #include <linux/rcupdate.h> 30 #include <linux/utsname.h> 31 #include <linux/workqueue.h> 32 #include <linux/in.h> 33 #include <linux/in6.h> 34 #include <linux/un.h> 35 36 #include <linux/sunrpc/clnt.h> 37 #include <linux/sunrpc/addr.h> 38 #include <linux/sunrpc/rpc_pipe_fs.h> 39 #include <linux/sunrpc/metrics.h> 40 #include <linux/sunrpc/bc_xprt.h> 41 #include <trace/events/sunrpc.h> 42 43 #include "sunrpc.h" 44 #include "sysfs.h" 45 #include "netns.h" 46 47 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 48 # define RPCDBG_FACILITY RPCDBG_CALL 49 #endif 50 51 /* 52 * All RPC clients are linked into this list 53 */ 54 55 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 56 57 58 static void call_start(struct rpc_task *task); 59 static void call_reserve(struct rpc_task *task); 60 static void call_reserveresult(struct rpc_task *task); 61 static void call_allocate(struct rpc_task *task); 62 static void call_encode(struct rpc_task *task); 63 static void call_decode(struct rpc_task *task); 64 static void call_bind(struct rpc_task *task); 65 static void call_bind_status(struct rpc_task *task); 66 static void call_transmit(struct rpc_task *task); 67 static void call_status(struct rpc_task *task); 68 static void call_transmit_status(struct rpc_task *task); 69 static void call_refresh(struct rpc_task *task); 70 static void call_refreshresult(struct rpc_task *task); 71 static void call_connect(struct rpc_task *task); 72 static void call_connect_status(struct rpc_task *task); 73 74 static int rpc_encode_header(struct rpc_task *task, 75 struct xdr_stream *xdr); 76 static int rpc_decode_header(struct rpc_task *task, 77 struct xdr_stream *xdr); 78 static int rpc_ping(struct rpc_clnt *clnt); 79 static int rpc_ping_noreply(struct rpc_clnt *clnt); 80 static void rpc_check_timeout(struct rpc_task *task); 81 82 static void rpc_register_client(struct rpc_clnt *clnt) 83 { 84 struct net *net = rpc_net_ns(clnt); 85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 86 87 spin_lock(&sn->rpc_client_lock); 88 list_add(&clnt->cl_clients, &sn->all_clients); 89 spin_unlock(&sn->rpc_client_lock); 90 } 91 92 static void rpc_unregister_client(struct rpc_clnt *clnt) 93 { 94 struct net *net = rpc_net_ns(clnt); 95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 96 97 spin_lock(&sn->rpc_client_lock); 98 list_del(&clnt->cl_clients); 99 spin_unlock(&sn->rpc_client_lock); 100 } 101 102 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 103 { 104 rpc_remove_client_dir(clnt); 105 } 106 107 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 108 { 109 struct net *net = rpc_net_ns(clnt); 110 struct super_block *pipefs_sb; 111 112 pipefs_sb = rpc_get_sb_net(net); 113 if (pipefs_sb) { 114 __rpc_clnt_remove_pipedir(clnt); 115 rpc_put_sb_net(net); 116 } 117 } 118 119 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 120 struct rpc_clnt *clnt) 121 { 122 static uint32_t clntid; 123 const char *dir_name = clnt->cl_program->pipe_dir_name; 124 char name[15]; 125 struct dentry *dir, *dentry; 126 127 dir = rpc_d_lookup_sb(sb, dir_name); 128 if (dir == NULL) { 129 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 130 return dir; 131 } 132 for (;;) { 133 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 134 name[sizeof(name) - 1] = '\0'; 135 dentry = rpc_create_client_dir(dir, name, clnt); 136 if (!IS_ERR(dentry)) 137 break; 138 if (dentry == ERR_PTR(-EEXIST)) 139 continue; 140 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 141 " %s/%s, error %ld\n", 142 dir_name, name, PTR_ERR(dentry)); 143 break; 144 } 145 dput(dir); 146 return dentry; 147 } 148 149 static int 150 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt) 151 { 152 struct dentry *dentry; 153 154 if (clnt->cl_program->pipe_dir_name != NULL) { 155 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); 156 if (IS_ERR(dentry)) 157 return PTR_ERR(dentry); 158 } 159 return 0; 160 } 161 162 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 163 { 164 if (clnt->cl_program->pipe_dir_name == NULL) 165 return 1; 166 167 switch (event) { 168 case RPC_PIPEFS_MOUNT: 169 if (clnt->cl_pipedir_objects.pdh_dentry != NULL) 170 return 1; 171 if (refcount_read(&clnt->cl_count) == 0) 172 return 1; 173 break; 174 case RPC_PIPEFS_UMOUNT: 175 if (clnt->cl_pipedir_objects.pdh_dentry == NULL) 176 return 1; 177 break; 178 } 179 return 0; 180 } 181 182 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 183 struct super_block *sb) 184 { 185 struct dentry *dentry; 186 187 switch (event) { 188 case RPC_PIPEFS_MOUNT: 189 dentry = rpc_setup_pipedir_sb(sb, clnt); 190 if (!dentry) 191 return -ENOENT; 192 if (IS_ERR(dentry)) 193 return PTR_ERR(dentry); 194 break; 195 case RPC_PIPEFS_UMOUNT: 196 __rpc_clnt_remove_pipedir(clnt); 197 break; 198 default: 199 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 200 return -ENOTSUPP; 201 } 202 return 0; 203 } 204 205 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 206 struct super_block *sb) 207 { 208 int error = 0; 209 210 for (;; clnt = clnt->cl_parent) { 211 if (!rpc_clnt_skip_event(clnt, event)) 212 error = __rpc_clnt_handle_event(clnt, event, sb); 213 if (error || clnt == clnt->cl_parent) 214 break; 215 } 216 return error; 217 } 218 219 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 220 { 221 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 222 struct rpc_clnt *clnt; 223 224 spin_lock(&sn->rpc_client_lock); 225 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 226 if (rpc_clnt_skip_event(clnt, event)) 227 continue; 228 spin_unlock(&sn->rpc_client_lock); 229 return clnt; 230 } 231 spin_unlock(&sn->rpc_client_lock); 232 return NULL; 233 } 234 235 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 236 void *ptr) 237 { 238 struct super_block *sb = ptr; 239 struct rpc_clnt *clnt; 240 int error = 0; 241 242 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 243 error = __rpc_pipefs_event(clnt, event, sb); 244 if (error) 245 break; 246 } 247 return error; 248 } 249 250 static struct notifier_block rpc_clients_block = { 251 .notifier_call = rpc_pipefs_event, 252 .priority = SUNRPC_PIPEFS_RPC_PRIO, 253 }; 254 255 int rpc_clients_notifier_register(void) 256 { 257 return rpc_pipefs_notifier_register(&rpc_clients_block); 258 } 259 260 void rpc_clients_notifier_unregister(void) 261 { 262 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 263 } 264 265 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, 266 struct rpc_xprt *xprt, 267 const struct rpc_timeout *timeout) 268 { 269 struct rpc_xprt *old; 270 271 spin_lock(&clnt->cl_lock); 272 old = rcu_dereference_protected(clnt->cl_xprt, 273 lockdep_is_held(&clnt->cl_lock)); 274 275 if (!xprt_bound(xprt)) 276 clnt->cl_autobind = 1; 277 278 clnt->cl_timeout = timeout; 279 rcu_assign_pointer(clnt->cl_xprt, xprt); 280 spin_unlock(&clnt->cl_lock); 281 282 return old; 283 } 284 285 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 286 { 287 clnt->cl_nodelen = strlcpy(clnt->cl_nodename, 288 nodename, sizeof(clnt->cl_nodename)); 289 } 290 291 static int rpc_client_register(struct rpc_clnt *clnt, 292 rpc_authflavor_t pseudoflavor, 293 const char *client_name) 294 { 295 struct rpc_auth_create_args auth_args = { 296 .pseudoflavor = pseudoflavor, 297 .target_name = client_name, 298 }; 299 struct rpc_auth *auth; 300 struct net *net = rpc_net_ns(clnt); 301 struct super_block *pipefs_sb; 302 int err; 303 304 rpc_clnt_debugfs_register(clnt); 305 306 pipefs_sb = rpc_get_sb_net(net); 307 if (pipefs_sb) { 308 err = rpc_setup_pipedir(pipefs_sb, clnt); 309 if (err) 310 goto out; 311 } 312 313 rpc_register_client(clnt); 314 if (pipefs_sb) 315 rpc_put_sb_net(net); 316 317 auth = rpcauth_create(&auth_args, clnt); 318 if (IS_ERR(auth)) { 319 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 320 pseudoflavor); 321 err = PTR_ERR(auth); 322 goto err_auth; 323 } 324 return 0; 325 err_auth: 326 pipefs_sb = rpc_get_sb_net(net); 327 rpc_unregister_client(clnt); 328 __rpc_clnt_remove_pipedir(clnt); 329 out: 330 if (pipefs_sb) 331 rpc_put_sb_net(net); 332 rpc_sysfs_client_destroy(clnt); 333 rpc_clnt_debugfs_unregister(clnt); 334 return err; 335 } 336 337 static DEFINE_IDA(rpc_clids); 338 339 void rpc_cleanup_clids(void) 340 { 341 ida_destroy(&rpc_clids); 342 } 343 344 static int rpc_alloc_clid(struct rpc_clnt *clnt) 345 { 346 int clid; 347 348 clid = ida_alloc(&rpc_clids, GFP_KERNEL); 349 if (clid < 0) 350 return clid; 351 clnt->cl_clid = clid; 352 return 0; 353 } 354 355 static void rpc_free_clid(struct rpc_clnt *clnt) 356 { 357 ida_free(&rpc_clids, clnt->cl_clid); 358 } 359 360 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 361 struct rpc_xprt_switch *xps, 362 struct rpc_xprt *xprt, 363 struct rpc_clnt *parent) 364 { 365 const struct rpc_program *program = args->program; 366 const struct rpc_version *version; 367 struct rpc_clnt *clnt = NULL; 368 const struct rpc_timeout *timeout; 369 const char *nodename = args->nodename; 370 int err; 371 372 err = rpciod_up(); 373 if (err) 374 goto out_no_rpciod; 375 376 err = -EINVAL; 377 if (args->version >= program->nrvers) 378 goto out_err; 379 version = program->version[args->version]; 380 if (version == NULL) 381 goto out_err; 382 383 err = -ENOMEM; 384 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 385 if (!clnt) 386 goto out_err; 387 clnt->cl_parent = parent ? : clnt; 388 389 err = rpc_alloc_clid(clnt); 390 if (err) 391 goto out_no_clid; 392 393 clnt->cl_cred = get_cred(args->cred); 394 clnt->cl_procinfo = version->procs; 395 clnt->cl_maxproc = version->nrprocs; 396 clnt->cl_prog = args->prognumber ? : program->number; 397 clnt->cl_vers = version->number; 398 clnt->cl_stats = program->stats; 399 clnt->cl_metrics = rpc_alloc_iostats(clnt); 400 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 401 err = -ENOMEM; 402 if (clnt->cl_metrics == NULL) 403 goto out_no_stats; 404 clnt->cl_program = program; 405 INIT_LIST_HEAD(&clnt->cl_tasks); 406 spin_lock_init(&clnt->cl_lock); 407 408 timeout = xprt->timeout; 409 if (args->timeout != NULL) { 410 memcpy(&clnt->cl_timeout_default, args->timeout, 411 sizeof(clnt->cl_timeout_default)); 412 timeout = &clnt->cl_timeout_default; 413 } 414 415 rpc_clnt_set_transport(clnt, xprt, timeout); 416 xprt->main = true; 417 xprt_iter_init(&clnt->cl_xpi, xps); 418 xprt_switch_put(xps); 419 420 clnt->cl_rtt = &clnt->cl_rtt_default; 421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 422 423 refcount_set(&clnt->cl_count, 1); 424 425 if (nodename == NULL) 426 nodename = utsname()->nodename; 427 /* save the nodename */ 428 rpc_clnt_set_nodename(clnt, nodename); 429 430 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt)); 431 err = rpc_client_register(clnt, args->authflavor, args->client_name); 432 if (err) 433 goto out_no_path; 434 if (parent) 435 refcount_inc(&parent->cl_count); 436 437 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername); 438 return clnt; 439 440 out_no_path: 441 rpc_free_iostats(clnt->cl_metrics); 442 out_no_stats: 443 put_cred(clnt->cl_cred); 444 rpc_free_clid(clnt); 445 out_no_clid: 446 kfree(clnt); 447 out_err: 448 rpciod_down(); 449 out_no_rpciod: 450 xprt_switch_put(xps); 451 xprt_put(xprt); 452 trace_rpc_clnt_new_err(program->name, args->servername, err); 453 return ERR_PTR(err); 454 } 455 456 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 457 struct rpc_xprt *xprt) 458 { 459 struct rpc_clnt *clnt = NULL; 460 struct rpc_xprt_switch *xps; 461 462 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) { 463 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 464 xps = args->bc_xprt->xpt_bc_xps; 465 xprt_switch_get(xps); 466 } else { 467 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 468 if (xps == NULL) { 469 xprt_put(xprt); 470 return ERR_PTR(-ENOMEM); 471 } 472 if (xprt->bc_xprt) { 473 xprt_switch_get(xps); 474 xprt->bc_xprt->xpt_bc_xps = xps; 475 } 476 } 477 clnt = rpc_new_client(args, xps, xprt, NULL); 478 if (IS_ERR(clnt)) 479 return clnt; 480 481 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 482 int err = rpc_ping(clnt); 483 if (err != 0) { 484 rpc_shutdown_client(clnt); 485 return ERR_PTR(err); 486 } 487 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) { 488 int err = rpc_ping_noreply(clnt); 489 if (err != 0) { 490 rpc_shutdown_client(clnt); 491 return ERR_PTR(err); 492 } 493 } 494 495 clnt->cl_softrtry = 1; 496 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) { 497 clnt->cl_softrtry = 0; 498 if (args->flags & RPC_CLNT_CREATE_SOFTERR) 499 clnt->cl_softerr = 1; 500 } 501 502 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 503 clnt->cl_autobind = 1; 504 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 505 clnt->cl_noretranstimeo = 1; 506 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 507 clnt->cl_discrtry = 1; 508 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 509 clnt->cl_chatty = 1; 510 511 return clnt; 512 } 513 514 /** 515 * rpc_create - create an RPC client and transport with one call 516 * @args: rpc_clnt create argument structure 517 * 518 * Creates and initializes an RPC transport and an RPC client. 519 * 520 * It can ping the server in order to determine if it is up, and to see if 521 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 522 * this behavior so asynchronous tasks can also use rpc_create. 523 */ 524 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 525 { 526 struct rpc_xprt *xprt; 527 struct xprt_create xprtargs = { 528 .net = args->net, 529 .ident = args->protocol, 530 .srcaddr = args->saddress, 531 .dstaddr = args->address, 532 .addrlen = args->addrsize, 533 .servername = args->servername, 534 .bc_xprt = args->bc_xprt, 535 }; 536 char servername[48]; 537 struct rpc_clnt *clnt; 538 int i; 539 540 if (args->bc_xprt) { 541 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 542 xprt = args->bc_xprt->xpt_bc_xprt; 543 if (xprt) { 544 xprt_get(xprt); 545 return rpc_create_xprt(args, xprt); 546 } 547 } 548 549 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 550 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 551 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 552 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 553 /* 554 * If the caller chooses not to specify a hostname, whip 555 * up a string representation of the passed-in address. 556 */ 557 if (xprtargs.servername == NULL) { 558 struct sockaddr_un *sun = 559 (struct sockaddr_un *)args->address; 560 struct sockaddr_in *sin = 561 (struct sockaddr_in *)args->address; 562 struct sockaddr_in6 *sin6 = 563 (struct sockaddr_in6 *)args->address; 564 565 servername[0] = '\0'; 566 switch (args->address->sa_family) { 567 case AF_LOCAL: 568 snprintf(servername, sizeof(servername), "%s", 569 sun->sun_path); 570 break; 571 case AF_INET: 572 snprintf(servername, sizeof(servername), "%pI4", 573 &sin->sin_addr.s_addr); 574 break; 575 case AF_INET6: 576 snprintf(servername, sizeof(servername), "%pI6", 577 &sin6->sin6_addr); 578 break; 579 default: 580 /* caller wants default server name, but 581 * address family isn't recognized. */ 582 return ERR_PTR(-EINVAL); 583 } 584 xprtargs.servername = servername; 585 } 586 587 xprt = xprt_create_transport(&xprtargs); 588 if (IS_ERR(xprt)) 589 return (struct rpc_clnt *)xprt; 590 591 /* 592 * By default, kernel RPC client connects from a reserved port. 593 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 594 * but it is always enabled for rpciod, which handles the connect 595 * operation. 596 */ 597 xprt->resvport = 1; 598 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 599 xprt->resvport = 0; 600 xprt->reuseport = 0; 601 if (args->flags & RPC_CLNT_CREATE_REUSEPORT) 602 xprt->reuseport = 1; 603 604 clnt = rpc_create_xprt(args, xprt); 605 if (IS_ERR(clnt) || args->nconnect <= 1) 606 return clnt; 607 608 for (i = 0; i < args->nconnect - 1; i++) { 609 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0) 610 break; 611 } 612 return clnt; 613 } 614 EXPORT_SYMBOL_GPL(rpc_create); 615 616 /* 617 * This function clones the RPC client structure. It allows us to share the 618 * same transport while varying parameters such as the authentication 619 * flavour. 620 */ 621 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 622 struct rpc_clnt *clnt) 623 { 624 struct rpc_xprt_switch *xps; 625 struct rpc_xprt *xprt; 626 struct rpc_clnt *new; 627 int err; 628 629 err = -ENOMEM; 630 rcu_read_lock(); 631 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 632 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 633 rcu_read_unlock(); 634 if (xprt == NULL || xps == NULL) { 635 xprt_put(xprt); 636 xprt_switch_put(xps); 637 goto out_err; 638 } 639 args->servername = xprt->servername; 640 args->nodename = clnt->cl_nodename; 641 642 new = rpc_new_client(args, xps, xprt, clnt); 643 if (IS_ERR(new)) 644 return new; 645 646 /* Turn off autobind on clones */ 647 new->cl_autobind = 0; 648 new->cl_softrtry = clnt->cl_softrtry; 649 new->cl_softerr = clnt->cl_softerr; 650 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 651 new->cl_discrtry = clnt->cl_discrtry; 652 new->cl_chatty = clnt->cl_chatty; 653 new->cl_principal = clnt->cl_principal; 654 new->cl_max_connect = clnt->cl_max_connect; 655 return new; 656 657 out_err: 658 trace_rpc_clnt_clone_err(clnt, err); 659 return ERR_PTR(err); 660 } 661 662 /** 663 * rpc_clone_client - Clone an RPC client structure 664 * 665 * @clnt: RPC client whose parameters are copied 666 * 667 * Returns a fresh RPC client or an ERR_PTR. 668 */ 669 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 670 { 671 struct rpc_create_args args = { 672 .program = clnt->cl_program, 673 .prognumber = clnt->cl_prog, 674 .version = clnt->cl_vers, 675 .authflavor = clnt->cl_auth->au_flavor, 676 .cred = clnt->cl_cred, 677 }; 678 return __rpc_clone_client(&args, clnt); 679 } 680 EXPORT_SYMBOL_GPL(rpc_clone_client); 681 682 /** 683 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 684 * 685 * @clnt: RPC client whose parameters are copied 686 * @flavor: security flavor for new client 687 * 688 * Returns a fresh RPC client or an ERR_PTR. 689 */ 690 struct rpc_clnt * 691 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 692 { 693 struct rpc_create_args args = { 694 .program = clnt->cl_program, 695 .prognumber = clnt->cl_prog, 696 .version = clnt->cl_vers, 697 .authflavor = flavor, 698 .cred = clnt->cl_cred, 699 }; 700 return __rpc_clone_client(&args, clnt); 701 } 702 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 703 704 /** 705 * rpc_switch_client_transport: switch the RPC transport on the fly 706 * @clnt: pointer to a struct rpc_clnt 707 * @args: pointer to the new transport arguments 708 * @timeout: pointer to the new timeout parameters 709 * 710 * This function allows the caller to switch the RPC transport for the 711 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 712 * server, for instance. It assumes that the caller has ensured that 713 * there are no active RPC tasks by using some form of locking. 714 * 715 * Returns zero if "clnt" is now using the new xprt. Otherwise a 716 * negative errno is returned, and "clnt" continues to use the old 717 * xprt. 718 */ 719 int rpc_switch_client_transport(struct rpc_clnt *clnt, 720 struct xprt_create *args, 721 const struct rpc_timeout *timeout) 722 { 723 const struct rpc_timeout *old_timeo; 724 rpc_authflavor_t pseudoflavor; 725 struct rpc_xprt_switch *xps, *oldxps; 726 struct rpc_xprt *xprt, *old; 727 struct rpc_clnt *parent; 728 int err; 729 730 xprt = xprt_create_transport(args); 731 if (IS_ERR(xprt)) 732 return PTR_ERR(xprt); 733 734 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 735 if (xps == NULL) { 736 xprt_put(xprt); 737 return -ENOMEM; 738 } 739 740 pseudoflavor = clnt->cl_auth->au_flavor; 741 742 old_timeo = clnt->cl_timeout; 743 old = rpc_clnt_set_transport(clnt, xprt, timeout); 744 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps); 745 746 rpc_unregister_client(clnt); 747 __rpc_clnt_remove_pipedir(clnt); 748 rpc_sysfs_client_destroy(clnt); 749 rpc_clnt_debugfs_unregister(clnt); 750 751 /* 752 * A new transport was created. "clnt" therefore 753 * becomes the root of a new cl_parent tree. clnt's 754 * children, if it has any, still point to the old xprt. 755 */ 756 parent = clnt->cl_parent; 757 clnt->cl_parent = clnt; 758 759 /* 760 * The old rpc_auth cache cannot be re-used. GSS 761 * contexts in particular are between a single 762 * client and server. 763 */ 764 err = rpc_client_register(clnt, pseudoflavor, NULL); 765 if (err) 766 goto out_revert; 767 768 synchronize_rcu(); 769 if (parent != clnt) 770 rpc_release_client(parent); 771 xprt_switch_put(oldxps); 772 xprt_put(old); 773 trace_rpc_clnt_replace_xprt(clnt); 774 return 0; 775 776 out_revert: 777 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps); 778 rpc_clnt_set_transport(clnt, old, old_timeo); 779 clnt->cl_parent = parent; 780 rpc_client_register(clnt, pseudoflavor, NULL); 781 xprt_switch_put(xps); 782 xprt_put(xprt); 783 trace_rpc_clnt_replace_xprt_err(clnt); 784 return err; 785 } 786 EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 787 788 static 789 int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi, 790 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps)) 791 { 792 struct rpc_xprt_switch *xps; 793 794 rcu_read_lock(); 795 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 796 rcu_read_unlock(); 797 if (xps == NULL) 798 return -EAGAIN; 799 func(xpi, xps); 800 xprt_switch_put(xps); 801 return 0; 802 } 803 804 static 805 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi) 806 { 807 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall); 808 } 809 810 static 811 int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt, 812 struct rpc_xprt_iter *xpi) 813 { 814 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline); 815 } 816 817 /** 818 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports 819 * @clnt: pointer to client 820 * @fn: function to apply 821 * @data: void pointer to function data 822 * 823 * Iterates through the list of RPC transports currently attached to the 824 * client and applies the function fn(clnt, xprt, data). 825 * 826 * On error, the iteration stops, and the function returns the error value. 827 */ 828 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 829 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), 830 void *data) 831 { 832 struct rpc_xprt_iter xpi; 833 int ret; 834 835 ret = rpc_clnt_xprt_iter_init(clnt, &xpi); 836 if (ret) 837 return ret; 838 for (;;) { 839 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 840 841 if (!xprt) 842 break; 843 ret = fn(clnt, xprt, data); 844 xprt_put(xprt); 845 if (ret < 0) 846 break; 847 } 848 xprt_iter_destroy(&xpi); 849 return ret; 850 } 851 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); 852 853 /* 854 * Kill all tasks for the given client. 855 * XXX: kill their descendants as well? 856 */ 857 void rpc_killall_tasks(struct rpc_clnt *clnt) 858 { 859 struct rpc_task *rovr; 860 861 862 if (list_empty(&clnt->cl_tasks)) 863 return; 864 865 /* 866 * Spin lock all_tasks to prevent changes... 867 */ 868 trace_rpc_clnt_killall(clnt); 869 spin_lock(&clnt->cl_lock); 870 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) 871 rpc_signal_task(rovr); 872 spin_unlock(&clnt->cl_lock); 873 } 874 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 875 876 /** 877 * rpc_cancel_tasks - try to cancel a set of RPC tasks 878 * @clnt: Pointer to RPC client 879 * @error: RPC task error value to set 880 * @fnmatch: Pointer to selector function 881 * @data: User data 882 * 883 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled. 884 * The argument @error must be a negative error value. 885 */ 886 unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error, 887 bool (*fnmatch)(const struct rpc_task *, 888 const void *), 889 const void *data) 890 { 891 struct rpc_task *task; 892 unsigned long count = 0; 893 894 if (list_empty(&clnt->cl_tasks)) 895 return 0; 896 /* 897 * Spin lock all_tasks to prevent changes... 898 */ 899 spin_lock(&clnt->cl_lock); 900 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 901 if (!RPC_IS_ACTIVATED(task)) 902 continue; 903 if (!fnmatch(task, data)) 904 continue; 905 rpc_task_try_cancel(task, error); 906 count++; 907 } 908 spin_unlock(&clnt->cl_lock); 909 return count; 910 } 911 EXPORT_SYMBOL_GPL(rpc_cancel_tasks); 912 913 static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt, 914 struct rpc_xprt *xprt, void *dummy) 915 { 916 if (xprt_connected(xprt)) 917 xprt_force_disconnect(xprt); 918 return 0; 919 } 920 921 void rpc_clnt_disconnect(struct rpc_clnt *clnt) 922 { 923 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL); 924 } 925 EXPORT_SYMBOL_GPL(rpc_clnt_disconnect); 926 927 /* 928 * Properly shut down an RPC client, terminating all outstanding 929 * requests. 930 */ 931 void rpc_shutdown_client(struct rpc_clnt *clnt) 932 { 933 might_sleep(); 934 935 trace_rpc_clnt_shutdown(clnt); 936 937 while (!list_empty(&clnt->cl_tasks)) { 938 rpc_killall_tasks(clnt); 939 wait_event_timeout(destroy_wait, 940 list_empty(&clnt->cl_tasks), 1*HZ); 941 } 942 943 rpc_release_client(clnt); 944 } 945 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 946 947 /* 948 * Free an RPC client 949 */ 950 static void rpc_free_client_work(struct work_struct *work) 951 { 952 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work); 953 954 trace_rpc_clnt_free(clnt); 955 956 /* These might block on processes that might allocate memory, 957 * so they cannot be called in rpciod, so they are handled separately 958 * here. 959 */ 960 rpc_sysfs_client_destroy(clnt); 961 rpc_clnt_debugfs_unregister(clnt); 962 rpc_free_clid(clnt); 963 rpc_clnt_remove_pipedir(clnt); 964 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 965 966 kfree(clnt); 967 rpciod_down(); 968 } 969 static struct rpc_clnt * 970 rpc_free_client(struct rpc_clnt *clnt) 971 { 972 struct rpc_clnt *parent = NULL; 973 974 trace_rpc_clnt_release(clnt); 975 if (clnt->cl_parent != clnt) 976 parent = clnt->cl_parent; 977 rpc_unregister_client(clnt); 978 rpc_free_iostats(clnt->cl_metrics); 979 clnt->cl_metrics = NULL; 980 xprt_iter_destroy(&clnt->cl_xpi); 981 put_cred(clnt->cl_cred); 982 983 INIT_WORK(&clnt->cl_work, rpc_free_client_work); 984 schedule_work(&clnt->cl_work); 985 return parent; 986 } 987 988 /* 989 * Free an RPC client 990 */ 991 static struct rpc_clnt * 992 rpc_free_auth(struct rpc_clnt *clnt) 993 { 994 /* 995 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 996 * release remaining GSS contexts. This mechanism ensures 997 * that it can do so safely. 998 */ 999 if (clnt->cl_auth != NULL) { 1000 rpcauth_release(clnt->cl_auth); 1001 clnt->cl_auth = NULL; 1002 } 1003 if (refcount_dec_and_test(&clnt->cl_count)) 1004 return rpc_free_client(clnt); 1005 return NULL; 1006 } 1007 1008 /* 1009 * Release reference to the RPC client 1010 */ 1011 void 1012 rpc_release_client(struct rpc_clnt *clnt) 1013 { 1014 do { 1015 if (list_empty(&clnt->cl_tasks)) 1016 wake_up(&destroy_wait); 1017 if (refcount_dec_not_one(&clnt->cl_count)) 1018 break; 1019 clnt = rpc_free_auth(clnt); 1020 } while (clnt != NULL); 1021 } 1022 EXPORT_SYMBOL_GPL(rpc_release_client); 1023 1024 /** 1025 * rpc_bind_new_program - bind a new RPC program to an existing client 1026 * @old: old rpc_client 1027 * @program: rpc program to set 1028 * @vers: rpc program version 1029 * 1030 * Clones the rpc client and sets up a new RPC program. This is mainly 1031 * of use for enabling different RPC programs to share the same transport. 1032 * The Sun NFSv2/v3 ACL protocol can do this. 1033 */ 1034 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 1035 const struct rpc_program *program, 1036 u32 vers) 1037 { 1038 struct rpc_create_args args = { 1039 .program = program, 1040 .prognumber = program->number, 1041 .version = vers, 1042 .authflavor = old->cl_auth->au_flavor, 1043 .cred = old->cl_cred, 1044 }; 1045 struct rpc_clnt *clnt; 1046 int err; 1047 1048 clnt = __rpc_clone_client(&args, old); 1049 if (IS_ERR(clnt)) 1050 goto out; 1051 err = rpc_ping(clnt); 1052 if (err != 0) { 1053 rpc_shutdown_client(clnt); 1054 clnt = ERR_PTR(err); 1055 } 1056 out: 1057 return clnt; 1058 } 1059 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 1060 1061 struct rpc_xprt * 1062 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1063 { 1064 struct rpc_xprt_switch *xps; 1065 1066 if (!xprt) 1067 return NULL; 1068 rcu_read_lock(); 1069 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1070 atomic_long_inc(&xps->xps_queuelen); 1071 rcu_read_unlock(); 1072 atomic_long_inc(&xprt->queuelen); 1073 1074 return xprt; 1075 } 1076 1077 static void 1078 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1079 { 1080 struct rpc_xprt_switch *xps; 1081 1082 atomic_long_dec(&xprt->queuelen); 1083 rcu_read_lock(); 1084 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1085 atomic_long_dec(&xps->xps_queuelen); 1086 rcu_read_unlock(); 1087 1088 xprt_put(xprt); 1089 } 1090 1091 void rpc_task_release_transport(struct rpc_task *task) 1092 { 1093 struct rpc_xprt *xprt = task->tk_xprt; 1094 1095 if (xprt) { 1096 task->tk_xprt = NULL; 1097 if (task->tk_client) 1098 rpc_task_release_xprt(task->tk_client, xprt); 1099 else 1100 xprt_put(xprt); 1101 } 1102 } 1103 EXPORT_SYMBOL_GPL(rpc_task_release_transport); 1104 1105 void rpc_task_release_client(struct rpc_task *task) 1106 { 1107 struct rpc_clnt *clnt = task->tk_client; 1108 1109 rpc_task_release_transport(task); 1110 if (clnt != NULL) { 1111 /* Remove from client task list */ 1112 spin_lock(&clnt->cl_lock); 1113 list_del(&task->tk_task); 1114 spin_unlock(&clnt->cl_lock); 1115 task->tk_client = NULL; 1116 1117 rpc_release_client(clnt); 1118 } 1119 } 1120 1121 static struct rpc_xprt * 1122 rpc_task_get_first_xprt(struct rpc_clnt *clnt) 1123 { 1124 struct rpc_xprt *xprt; 1125 1126 rcu_read_lock(); 1127 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 1128 rcu_read_unlock(); 1129 return rpc_task_get_xprt(clnt, xprt); 1130 } 1131 1132 static struct rpc_xprt * 1133 rpc_task_get_next_xprt(struct rpc_clnt *clnt) 1134 { 1135 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi)); 1136 } 1137 1138 static 1139 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) 1140 { 1141 if (task->tk_xprt) { 1142 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) && 1143 (task->tk_flags & RPC_TASK_MOVEABLE))) 1144 return; 1145 xprt_release(task); 1146 xprt_put(task->tk_xprt); 1147 } 1148 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) 1149 task->tk_xprt = rpc_task_get_first_xprt(clnt); 1150 else 1151 task->tk_xprt = rpc_task_get_next_xprt(clnt); 1152 } 1153 1154 static 1155 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 1156 { 1157 rpc_task_set_transport(task, clnt); 1158 task->tk_client = clnt; 1159 refcount_inc(&clnt->cl_count); 1160 if (clnt->cl_softrtry) 1161 task->tk_flags |= RPC_TASK_SOFT; 1162 if (clnt->cl_softerr) 1163 task->tk_flags |= RPC_TASK_TIMEOUT; 1164 if (clnt->cl_noretranstimeo) 1165 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1166 /* Add to the client's list of all tasks */ 1167 spin_lock(&clnt->cl_lock); 1168 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1169 spin_unlock(&clnt->cl_lock); 1170 } 1171 1172 static void 1173 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1174 { 1175 if (msg != NULL) { 1176 task->tk_msg.rpc_proc = msg->rpc_proc; 1177 task->tk_msg.rpc_argp = msg->rpc_argp; 1178 task->tk_msg.rpc_resp = msg->rpc_resp; 1179 task->tk_msg.rpc_cred = msg->rpc_cred; 1180 if (!(task->tk_flags & RPC_TASK_CRED_NOREF)) 1181 get_cred(task->tk_msg.rpc_cred); 1182 } 1183 } 1184 1185 /* 1186 * Default callback for async RPC calls 1187 */ 1188 static void 1189 rpc_default_callback(struct rpc_task *task, void *data) 1190 { 1191 } 1192 1193 static const struct rpc_call_ops rpc_default_ops = { 1194 .rpc_call_done = rpc_default_callback, 1195 }; 1196 1197 /** 1198 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1199 * @task_setup_data: pointer to task initialisation data 1200 */ 1201 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1202 { 1203 struct rpc_task *task; 1204 1205 task = rpc_new_task(task_setup_data); 1206 if (IS_ERR(task)) 1207 return task; 1208 1209 if (!RPC_IS_ASYNC(task)) 1210 task->tk_flags |= RPC_TASK_CRED_NOREF; 1211 1212 rpc_task_set_client(task, task_setup_data->rpc_client); 1213 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1214 1215 if (task->tk_action == NULL) 1216 rpc_call_start(task); 1217 1218 atomic_inc(&task->tk_count); 1219 rpc_execute(task); 1220 return task; 1221 } 1222 EXPORT_SYMBOL_GPL(rpc_run_task); 1223 1224 /** 1225 * rpc_call_sync - Perform a synchronous RPC call 1226 * @clnt: pointer to RPC client 1227 * @msg: RPC call parameters 1228 * @flags: RPC call flags 1229 */ 1230 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1231 { 1232 struct rpc_task *task; 1233 struct rpc_task_setup task_setup_data = { 1234 .rpc_client = clnt, 1235 .rpc_message = msg, 1236 .callback_ops = &rpc_default_ops, 1237 .flags = flags, 1238 }; 1239 int status; 1240 1241 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1242 if (flags & RPC_TASK_ASYNC) { 1243 rpc_release_calldata(task_setup_data.callback_ops, 1244 task_setup_data.callback_data); 1245 return -EINVAL; 1246 } 1247 1248 task = rpc_run_task(&task_setup_data); 1249 if (IS_ERR(task)) 1250 return PTR_ERR(task); 1251 status = task->tk_status; 1252 rpc_put_task(task); 1253 return status; 1254 } 1255 EXPORT_SYMBOL_GPL(rpc_call_sync); 1256 1257 /** 1258 * rpc_call_async - Perform an asynchronous RPC call 1259 * @clnt: pointer to RPC client 1260 * @msg: RPC call parameters 1261 * @flags: RPC call flags 1262 * @tk_ops: RPC call ops 1263 * @data: user call data 1264 */ 1265 int 1266 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1267 const struct rpc_call_ops *tk_ops, void *data) 1268 { 1269 struct rpc_task *task; 1270 struct rpc_task_setup task_setup_data = { 1271 .rpc_client = clnt, 1272 .rpc_message = msg, 1273 .callback_ops = tk_ops, 1274 .callback_data = data, 1275 .flags = flags|RPC_TASK_ASYNC, 1276 }; 1277 1278 task = rpc_run_task(&task_setup_data); 1279 if (IS_ERR(task)) 1280 return PTR_ERR(task); 1281 rpc_put_task(task); 1282 return 0; 1283 } 1284 EXPORT_SYMBOL_GPL(rpc_call_async); 1285 1286 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1287 static void call_bc_encode(struct rpc_task *task); 1288 1289 /** 1290 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1291 * rpc_execute against it 1292 * @req: RPC request 1293 */ 1294 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) 1295 { 1296 struct rpc_task *task; 1297 struct rpc_task_setup task_setup_data = { 1298 .callback_ops = &rpc_default_ops, 1299 .flags = RPC_TASK_SOFTCONN | 1300 RPC_TASK_NO_RETRANS_TIMEOUT, 1301 }; 1302 1303 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1304 /* 1305 * Create an rpc_task to send the data 1306 */ 1307 task = rpc_new_task(&task_setup_data); 1308 if (IS_ERR(task)) { 1309 xprt_free_bc_request(req); 1310 return task; 1311 } 1312 1313 xprt_init_bc_request(req, task); 1314 1315 task->tk_action = call_bc_encode; 1316 atomic_inc(&task->tk_count); 1317 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1318 rpc_execute(task); 1319 1320 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1321 return task; 1322 } 1323 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1324 1325 /** 1326 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages 1327 * @req: RPC request to prepare 1328 * @pages: vector of struct page pointers 1329 * @base: offset in first page where receive should start, in bytes 1330 * @len: expected size of the upper layer data payload, in bytes 1331 * @hdrsize: expected size of upper layer reply header, in XDR words 1332 * 1333 */ 1334 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, 1335 unsigned int base, unsigned int len, 1336 unsigned int hdrsize) 1337 { 1338 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; 1339 1340 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); 1341 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); 1342 } 1343 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages); 1344 1345 void 1346 rpc_call_start(struct rpc_task *task) 1347 { 1348 task->tk_action = call_start; 1349 } 1350 EXPORT_SYMBOL_GPL(rpc_call_start); 1351 1352 /** 1353 * rpc_peeraddr - extract remote peer address from clnt's xprt 1354 * @clnt: RPC client structure 1355 * @buf: target buffer 1356 * @bufsize: length of target buffer 1357 * 1358 * Returns the number of bytes that are actually in the stored address. 1359 */ 1360 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1361 { 1362 size_t bytes; 1363 struct rpc_xprt *xprt; 1364 1365 rcu_read_lock(); 1366 xprt = rcu_dereference(clnt->cl_xprt); 1367 1368 bytes = xprt->addrlen; 1369 if (bytes > bufsize) 1370 bytes = bufsize; 1371 memcpy(buf, &xprt->addr, bytes); 1372 rcu_read_unlock(); 1373 1374 return bytes; 1375 } 1376 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1377 1378 /** 1379 * rpc_peeraddr2str - return remote peer address in printable format 1380 * @clnt: RPC client structure 1381 * @format: address format 1382 * 1383 * NB: the lifetime of the memory referenced by the returned pointer is 1384 * the same as the rpc_xprt itself. As long as the caller uses this 1385 * pointer, it must hold the RCU read lock. 1386 */ 1387 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1388 enum rpc_display_format_t format) 1389 { 1390 struct rpc_xprt *xprt; 1391 1392 xprt = rcu_dereference(clnt->cl_xprt); 1393 1394 if (xprt->address_strings[format] != NULL) 1395 return xprt->address_strings[format]; 1396 else 1397 return "unprintable"; 1398 } 1399 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1400 1401 static const struct sockaddr_in rpc_inaddr_loopback = { 1402 .sin_family = AF_INET, 1403 .sin_addr.s_addr = htonl(INADDR_ANY), 1404 }; 1405 1406 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1407 .sin6_family = AF_INET6, 1408 .sin6_addr = IN6ADDR_ANY_INIT, 1409 }; 1410 1411 /* 1412 * Try a getsockname() on a connected datagram socket. Using a 1413 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1414 * This conserves the ephemeral port number space. 1415 * 1416 * Returns zero and fills in "buf" if successful; otherwise, a 1417 * negative errno is returned. 1418 */ 1419 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1420 struct sockaddr *buf) 1421 { 1422 struct socket *sock; 1423 int err; 1424 1425 err = __sock_create(net, sap->sa_family, 1426 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1427 if (err < 0) { 1428 dprintk("RPC: can't create UDP socket (%d)\n", err); 1429 goto out; 1430 } 1431 1432 switch (sap->sa_family) { 1433 case AF_INET: 1434 err = kernel_bind(sock, 1435 (struct sockaddr *)&rpc_inaddr_loopback, 1436 sizeof(rpc_inaddr_loopback)); 1437 break; 1438 case AF_INET6: 1439 err = kernel_bind(sock, 1440 (struct sockaddr *)&rpc_in6addr_loopback, 1441 sizeof(rpc_in6addr_loopback)); 1442 break; 1443 default: 1444 err = -EAFNOSUPPORT; 1445 goto out_release; 1446 } 1447 if (err < 0) { 1448 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1449 goto out_release; 1450 } 1451 1452 err = kernel_connect(sock, sap, salen, 0); 1453 if (err < 0) { 1454 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1455 goto out_release; 1456 } 1457 1458 err = kernel_getsockname(sock, buf); 1459 if (err < 0) { 1460 dprintk("RPC: getsockname failed (%d)\n", err); 1461 goto out_release; 1462 } 1463 1464 err = 0; 1465 if (buf->sa_family == AF_INET6) { 1466 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1467 sin6->sin6_scope_id = 0; 1468 } 1469 dprintk("RPC: %s succeeded\n", __func__); 1470 1471 out_release: 1472 sock_release(sock); 1473 out: 1474 return err; 1475 } 1476 1477 /* 1478 * Scraping a connected socket failed, so we don't have a useable 1479 * local address. Fallback: generate an address that will prevent 1480 * the server from calling us back. 1481 * 1482 * Returns zero and fills in "buf" if successful; otherwise, a 1483 * negative errno is returned. 1484 */ 1485 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1486 { 1487 switch (family) { 1488 case AF_INET: 1489 if (buflen < sizeof(rpc_inaddr_loopback)) 1490 return -EINVAL; 1491 memcpy(buf, &rpc_inaddr_loopback, 1492 sizeof(rpc_inaddr_loopback)); 1493 break; 1494 case AF_INET6: 1495 if (buflen < sizeof(rpc_in6addr_loopback)) 1496 return -EINVAL; 1497 memcpy(buf, &rpc_in6addr_loopback, 1498 sizeof(rpc_in6addr_loopback)); 1499 break; 1500 default: 1501 dprintk("RPC: %s: address family not supported\n", 1502 __func__); 1503 return -EAFNOSUPPORT; 1504 } 1505 dprintk("RPC: %s: succeeded\n", __func__); 1506 return 0; 1507 } 1508 1509 /** 1510 * rpc_localaddr - discover local endpoint address for an RPC client 1511 * @clnt: RPC client structure 1512 * @buf: target buffer 1513 * @buflen: size of target buffer, in bytes 1514 * 1515 * Returns zero and fills in "buf" and "buflen" if successful; 1516 * otherwise, a negative errno is returned. 1517 * 1518 * This works even if the underlying transport is not currently connected, 1519 * or if the upper layer never previously provided a source address. 1520 * 1521 * The result of this function call is transient: multiple calls in 1522 * succession may give different results, depending on how local 1523 * networking configuration changes over time. 1524 */ 1525 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1526 { 1527 struct sockaddr_storage address; 1528 struct sockaddr *sap = (struct sockaddr *)&address; 1529 struct rpc_xprt *xprt; 1530 struct net *net; 1531 size_t salen; 1532 int err; 1533 1534 rcu_read_lock(); 1535 xprt = rcu_dereference(clnt->cl_xprt); 1536 salen = xprt->addrlen; 1537 memcpy(sap, &xprt->addr, salen); 1538 net = get_net(xprt->xprt_net); 1539 rcu_read_unlock(); 1540 1541 rpc_set_port(sap, 0); 1542 err = rpc_sockname(net, sap, salen, buf); 1543 put_net(net); 1544 if (err != 0) 1545 /* Couldn't discover local address, return ANYADDR */ 1546 return rpc_anyaddr(sap->sa_family, buf, buflen); 1547 return 0; 1548 } 1549 EXPORT_SYMBOL_GPL(rpc_localaddr); 1550 1551 void 1552 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1553 { 1554 struct rpc_xprt *xprt; 1555 1556 rcu_read_lock(); 1557 xprt = rcu_dereference(clnt->cl_xprt); 1558 if (xprt->ops->set_buffer_size) 1559 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1560 rcu_read_unlock(); 1561 } 1562 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1563 1564 /** 1565 * rpc_net_ns - Get the network namespace for this RPC client 1566 * @clnt: RPC client to query 1567 * 1568 */ 1569 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1570 { 1571 struct net *ret; 1572 1573 rcu_read_lock(); 1574 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1575 rcu_read_unlock(); 1576 return ret; 1577 } 1578 EXPORT_SYMBOL_GPL(rpc_net_ns); 1579 1580 /** 1581 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1582 * @clnt: RPC client to query 1583 * 1584 * For stream transports, this is one RPC record fragment (see RFC 1585 * 1831), as we don't support multi-record requests yet. For datagram 1586 * transports, this is the size of an IP packet minus the IP, UDP, and 1587 * RPC header sizes. 1588 */ 1589 size_t rpc_max_payload(struct rpc_clnt *clnt) 1590 { 1591 size_t ret; 1592 1593 rcu_read_lock(); 1594 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1595 rcu_read_unlock(); 1596 return ret; 1597 } 1598 EXPORT_SYMBOL_GPL(rpc_max_payload); 1599 1600 /** 1601 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1602 * @clnt: RPC client to query 1603 */ 1604 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1605 { 1606 struct rpc_xprt *xprt; 1607 size_t ret; 1608 1609 rcu_read_lock(); 1610 xprt = rcu_dereference(clnt->cl_xprt); 1611 ret = xprt->ops->bc_maxpayload(xprt); 1612 rcu_read_unlock(); 1613 return ret; 1614 } 1615 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1616 1617 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt) 1618 { 1619 struct rpc_xprt *xprt; 1620 unsigned int ret; 1621 1622 rcu_read_lock(); 1623 xprt = rcu_dereference(clnt->cl_xprt); 1624 ret = xprt->ops->bc_num_slots(xprt); 1625 rcu_read_unlock(); 1626 return ret; 1627 } 1628 EXPORT_SYMBOL_GPL(rpc_num_bc_slots); 1629 1630 /** 1631 * rpc_force_rebind - force transport to check that remote port is unchanged 1632 * @clnt: client to rebind 1633 * 1634 */ 1635 void rpc_force_rebind(struct rpc_clnt *clnt) 1636 { 1637 if (clnt->cl_autobind) { 1638 rcu_read_lock(); 1639 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1640 rcu_read_unlock(); 1641 } 1642 } 1643 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1644 1645 static int 1646 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *)) 1647 { 1648 task->tk_status = 0; 1649 task->tk_rpc_status = 0; 1650 task->tk_action = action; 1651 return 1; 1652 } 1653 1654 /* 1655 * Restart an (async) RPC call. Usually called from within the 1656 * exit handler. 1657 */ 1658 int 1659 rpc_restart_call(struct rpc_task *task) 1660 { 1661 return __rpc_restart_call(task, call_start); 1662 } 1663 EXPORT_SYMBOL_GPL(rpc_restart_call); 1664 1665 /* 1666 * Restart an (async) RPC call from the call_prepare state. 1667 * Usually called from within the exit handler. 1668 */ 1669 int 1670 rpc_restart_call_prepare(struct rpc_task *task) 1671 { 1672 if (task->tk_ops->rpc_call_prepare != NULL) 1673 return __rpc_restart_call(task, rpc_prepare_task); 1674 return rpc_restart_call(task); 1675 } 1676 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1677 1678 const char 1679 *rpc_proc_name(const struct rpc_task *task) 1680 { 1681 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1682 1683 if (proc) { 1684 if (proc->p_name) 1685 return proc->p_name; 1686 else 1687 return "NULL"; 1688 } else 1689 return "no proc"; 1690 } 1691 1692 static void 1693 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status) 1694 { 1695 trace_rpc_call_rpcerror(task, tk_status, rpc_status); 1696 rpc_task_set_rpc_status(task, rpc_status); 1697 rpc_exit(task, tk_status); 1698 } 1699 1700 static void 1701 rpc_call_rpcerror(struct rpc_task *task, int status) 1702 { 1703 __rpc_call_rpcerror(task, status, status); 1704 } 1705 1706 /* 1707 * 0. Initial state 1708 * 1709 * Other FSM states can be visited zero or more times, but 1710 * this state is visited exactly once for each RPC. 1711 */ 1712 static void 1713 call_start(struct rpc_task *task) 1714 { 1715 struct rpc_clnt *clnt = task->tk_client; 1716 int idx = task->tk_msg.rpc_proc->p_statidx; 1717 1718 trace_rpc_request(task); 1719 1720 /* Increment call count (version might not be valid for ping) */ 1721 if (clnt->cl_program->version[clnt->cl_vers]) 1722 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; 1723 clnt->cl_stats->rpccnt++; 1724 task->tk_action = call_reserve; 1725 rpc_task_set_transport(task, clnt); 1726 } 1727 1728 /* 1729 * 1. Reserve an RPC call slot 1730 */ 1731 static void 1732 call_reserve(struct rpc_task *task) 1733 { 1734 task->tk_status = 0; 1735 task->tk_action = call_reserveresult; 1736 xprt_reserve(task); 1737 } 1738 1739 static void call_retry_reserve(struct rpc_task *task); 1740 1741 /* 1742 * 1b. Grok the result of xprt_reserve() 1743 */ 1744 static void 1745 call_reserveresult(struct rpc_task *task) 1746 { 1747 int status = task->tk_status; 1748 1749 /* 1750 * After a call to xprt_reserve(), we must have either 1751 * a request slot or else an error status. 1752 */ 1753 task->tk_status = 0; 1754 if (status >= 0) { 1755 if (task->tk_rqstp) { 1756 task->tk_action = call_refresh; 1757 return; 1758 } 1759 1760 rpc_call_rpcerror(task, -EIO); 1761 return; 1762 } 1763 1764 switch (status) { 1765 case -ENOMEM: 1766 rpc_delay(task, HZ >> 2); 1767 fallthrough; 1768 case -EAGAIN: /* woken up; retry */ 1769 task->tk_action = call_retry_reserve; 1770 return; 1771 default: 1772 rpc_call_rpcerror(task, status); 1773 } 1774 } 1775 1776 /* 1777 * 1c. Retry reserving an RPC call slot 1778 */ 1779 static void 1780 call_retry_reserve(struct rpc_task *task) 1781 { 1782 task->tk_status = 0; 1783 task->tk_action = call_reserveresult; 1784 xprt_retry_reserve(task); 1785 } 1786 1787 /* 1788 * 2. Bind and/or refresh the credentials 1789 */ 1790 static void 1791 call_refresh(struct rpc_task *task) 1792 { 1793 task->tk_action = call_refreshresult; 1794 task->tk_status = 0; 1795 task->tk_client->cl_stats->rpcauthrefresh++; 1796 rpcauth_refreshcred(task); 1797 } 1798 1799 /* 1800 * 2a. Process the results of a credential refresh 1801 */ 1802 static void 1803 call_refreshresult(struct rpc_task *task) 1804 { 1805 int status = task->tk_status; 1806 1807 task->tk_status = 0; 1808 task->tk_action = call_refresh; 1809 switch (status) { 1810 case 0: 1811 if (rpcauth_uptodatecred(task)) { 1812 task->tk_action = call_allocate; 1813 return; 1814 } 1815 /* Use rate-limiting and a max number of retries if refresh 1816 * had status 0 but failed to update the cred. 1817 */ 1818 fallthrough; 1819 case -ETIMEDOUT: 1820 rpc_delay(task, 3*HZ); 1821 fallthrough; 1822 case -EAGAIN: 1823 status = -EACCES; 1824 fallthrough; 1825 case -EKEYEXPIRED: 1826 if (!task->tk_cred_retry) 1827 break; 1828 task->tk_cred_retry--; 1829 trace_rpc_retry_refresh_status(task); 1830 return; 1831 case -ENOMEM: 1832 rpc_delay(task, HZ >> 4); 1833 return; 1834 } 1835 trace_rpc_refresh_status(task); 1836 rpc_call_rpcerror(task, status); 1837 } 1838 1839 /* 1840 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1841 * (Note: buffer memory is freed in xprt_release). 1842 */ 1843 static void 1844 call_allocate(struct rpc_task *task) 1845 { 1846 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth; 1847 struct rpc_rqst *req = task->tk_rqstp; 1848 struct rpc_xprt *xprt = req->rq_xprt; 1849 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1850 int status; 1851 1852 task->tk_status = 0; 1853 task->tk_action = call_encode; 1854 1855 if (req->rq_buffer) 1856 return; 1857 1858 if (proc->p_proc != 0) { 1859 BUG_ON(proc->p_arglen == 0); 1860 if (proc->p_decode != NULL) 1861 BUG_ON(proc->p_replen == 0); 1862 } 1863 1864 /* 1865 * Calculate the size (in quads) of the RPC call 1866 * and reply headers, and convert both values 1867 * to byte sizes. 1868 */ 1869 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + 1870 proc->p_arglen; 1871 req->rq_callsize <<= 2; 1872 /* 1873 * Note: the reply buffer must at minimum allocate enough space 1874 * for the 'struct accepted_reply' from RFC5531. 1875 */ 1876 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ 1877 max_t(size_t, proc->p_replen, 2); 1878 req->rq_rcvsize <<= 2; 1879 1880 status = xprt->ops->buf_alloc(task); 1881 trace_rpc_buf_alloc(task, status); 1882 if (status == 0) 1883 return; 1884 if (status != -ENOMEM) { 1885 rpc_call_rpcerror(task, status); 1886 return; 1887 } 1888 1889 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1890 task->tk_action = call_allocate; 1891 rpc_delay(task, HZ>>4); 1892 return; 1893 } 1894 1895 rpc_call_rpcerror(task, -ERESTARTSYS); 1896 } 1897 1898 static int 1899 rpc_task_need_encode(struct rpc_task *task) 1900 { 1901 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 && 1902 (!(task->tk_flags & RPC_TASK_SENT) || 1903 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) || 1904 xprt_request_need_retransmit(task)); 1905 } 1906 1907 static void 1908 rpc_xdr_encode(struct rpc_task *task) 1909 { 1910 struct rpc_rqst *req = task->tk_rqstp; 1911 struct xdr_stream xdr; 1912 1913 xdr_buf_init(&req->rq_snd_buf, 1914 req->rq_buffer, 1915 req->rq_callsize); 1916 xdr_buf_init(&req->rq_rcv_buf, 1917 req->rq_rbuffer, 1918 req->rq_rcvsize); 1919 1920 req->rq_reply_bytes_recvd = 0; 1921 req->rq_snd_buf.head[0].iov_len = 0; 1922 xdr_init_encode(&xdr, &req->rq_snd_buf, 1923 req->rq_snd_buf.head[0].iov_base, req); 1924 if (rpc_encode_header(task, &xdr)) 1925 return; 1926 1927 task->tk_status = rpcauth_wrap_req(task, &xdr); 1928 } 1929 1930 /* 1931 * 3. Encode arguments of an RPC call 1932 */ 1933 static void 1934 call_encode(struct rpc_task *task) 1935 { 1936 if (!rpc_task_need_encode(task)) 1937 goto out; 1938 1939 /* Dequeue task from the receive queue while we're encoding */ 1940 xprt_request_dequeue_xprt(task); 1941 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1942 rpc_xdr_encode(task); 1943 /* Add task to reply queue before transmission to avoid races */ 1944 if (task->tk_status == 0 && rpc_reply_expected(task)) 1945 task->tk_status = xprt_request_enqueue_receive(task); 1946 /* Did the encode result in an error condition? */ 1947 if (task->tk_status != 0) { 1948 /* Was the error nonfatal? */ 1949 switch (task->tk_status) { 1950 case -EAGAIN: 1951 case -ENOMEM: 1952 rpc_delay(task, HZ >> 4); 1953 break; 1954 case -EKEYEXPIRED: 1955 if (!task->tk_cred_retry) { 1956 rpc_call_rpcerror(task, task->tk_status); 1957 } else { 1958 task->tk_action = call_refresh; 1959 task->tk_cred_retry--; 1960 trace_rpc_retry_refresh_status(task); 1961 } 1962 break; 1963 default: 1964 rpc_call_rpcerror(task, task->tk_status); 1965 } 1966 return; 1967 } 1968 1969 xprt_request_enqueue_transmit(task); 1970 out: 1971 task->tk_action = call_transmit; 1972 /* Check that the connection is OK */ 1973 if (!xprt_bound(task->tk_xprt)) 1974 task->tk_action = call_bind; 1975 else if (!xprt_connected(task->tk_xprt)) 1976 task->tk_action = call_connect; 1977 } 1978 1979 /* 1980 * Helpers to check if the task was already transmitted, and 1981 * to take action when that is the case. 1982 */ 1983 static bool 1984 rpc_task_transmitted(struct rpc_task *task) 1985 { 1986 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1987 } 1988 1989 static void 1990 rpc_task_handle_transmitted(struct rpc_task *task) 1991 { 1992 xprt_end_transmit(task); 1993 task->tk_action = call_transmit_status; 1994 } 1995 1996 /* 1997 * 4. Get the server port number if not yet set 1998 */ 1999 static void 2000 call_bind(struct rpc_task *task) 2001 { 2002 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2003 2004 if (rpc_task_transmitted(task)) { 2005 rpc_task_handle_transmitted(task); 2006 return; 2007 } 2008 2009 if (xprt_bound(xprt)) { 2010 task->tk_action = call_connect; 2011 return; 2012 } 2013 2014 task->tk_action = call_bind_status; 2015 if (!xprt_prepare_transmit(task)) 2016 return; 2017 2018 xprt->ops->rpcbind(task); 2019 } 2020 2021 /* 2022 * 4a. Sort out bind result 2023 */ 2024 static void 2025 call_bind_status(struct rpc_task *task) 2026 { 2027 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2028 int status = -EIO; 2029 2030 if (rpc_task_transmitted(task)) { 2031 rpc_task_handle_transmitted(task); 2032 return; 2033 } 2034 2035 if (task->tk_status >= 0) 2036 goto out_next; 2037 if (xprt_bound(xprt)) { 2038 task->tk_status = 0; 2039 goto out_next; 2040 } 2041 2042 switch (task->tk_status) { 2043 case -ENOMEM: 2044 rpc_delay(task, HZ >> 2); 2045 goto retry_timeout; 2046 case -EACCES: 2047 trace_rpcb_prog_unavail_err(task); 2048 /* fail immediately if this is an RPC ping */ 2049 if (task->tk_msg.rpc_proc->p_proc == 0) { 2050 status = -EOPNOTSUPP; 2051 break; 2052 } 2053 rpc_delay(task, 3*HZ); 2054 goto retry_timeout; 2055 case -ENOBUFS: 2056 rpc_delay(task, HZ >> 2); 2057 goto retry_timeout; 2058 case -EAGAIN: 2059 goto retry_timeout; 2060 case -ETIMEDOUT: 2061 trace_rpcb_timeout_err(task); 2062 goto retry_timeout; 2063 case -EPFNOSUPPORT: 2064 /* server doesn't support any rpcbind version we know of */ 2065 trace_rpcb_bind_version_err(task); 2066 break; 2067 case -EPROTONOSUPPORT: 2068 trace_rpcb_bind_version_err(task); 2069 goto retry_timeout; 2070 case -ECONNREFUSED: /* connection problems */ 2071 case -ECONNRESET: 2072 case -ECONNABORTED: 2073 case -ENOTCONN: 2074 case -EHOSTDOWN: 2075 case -ENETDOWN: 2076 case -EHOSTUNREACH: 2077 case -ENETUNREACH: 2078 case -EPIPE: 2079 trace_rpcb_unreachable_err(task); 2080 if (!RPC_IS_SOFTCONN(task)) { 2081 rpc_delay(task, 5*HZ); 2082 goto retry_timeout; 2083 } 2084 status = task->tk_status; 2085 break; 2086 default: 2087 trace_rpcb_unrecognized_err(task); 2088 } 2089 2090 rpc_call_rpcerror(task, status); 2091 return; 2092 out_next: 2093 task->tk_action = call_connect; 2094 return; 2095 retry_timeout: 2096 task->tk_status = 0; 2097 task->tk_action = call_bind; 2098 rpc_check_timeout(task); 2099 } 2100 2101 /* 2102 * 4b. Connect to the RPC server 2103 */ 2104 static void 2105 call_connect(struct rpc_task *task) 2106 { 2107 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2108 2109 if (rpc_task_transmitted(task)) { 2110 rpc_task_handle_transmitted(task); 2111 return; 2112 } 2113 2114 if (xprt_connected(xprt)) { 2115 task->tk_action = call_transmit; 2116 return; 2117 } 2118 2119 task->tk_action = call_connect_status; 2120 if (task->tk_status < 0) 2121 return; 2122 if (task->tk_flags & RPC_TASK_NOCONNECT) { 2123 rpc_call_rpcerror(task, -ENOTCONN); 2124 return; 2125 } 2126 if (!xprt_prepare_transmit(task)) 2127 return; 2128 xprt_connect(task); 2129 } 2130 2131 /* 2132 * 4c. Sort out connect result 2133 */ 2134 static void 2135 call_connect_status(struct rpc_task *task) 2136 { 2137 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2138 struct rpc_clnt *clnt = task->tk_client; 2139 int status = task->tk_status; 2140 2141 if (rpc_task_transmitted(task)) { 2142 rpc_task_handle_transmitted(task); 2143 return; 2144 } 2145 2146 trace_rpc_connect_status(task); 2147 2148 if (task->tk_status == 0) { 2149 clnt->cl_stats->netreconn++; 2150 goto out_next; 2151 } 2152 if (xprt_connected(xprt)) { 2153 task->tk_status = 0; 2154 goto out_next; 2155 } 2156 2157 task->tk_status = 0; 2158 switch (status) { 2159 case -ECONNREFUSED: 2160 /* A positive refusal suggests a rebind is needed. */ 2161 if (RPC_IS_SOFTCONN(task)) 2162 break; 2163 if (clnt->cl_autobind) { 2164 rpc_force_rebind(clnt); 2165 goto out_retry; 2166 } 2167 fallthrough; 2168 case -ECONNRESET: 2169 case -ECONNABORTED: 2170 case -ENETDOWN: 2171 case -ENETUNREACH: 2172 case -EHOSTUNREACH: 2173 case -EPIPE: 2174 case -EPROTO: 2175 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, 2176 task->tk_rqstp->rq_connect_cookie); 2177 if (RPC_IS_SOFTCONN(task)) 2178 break; 2179 /* retry with existing socket, after a delay */ 2180 rpc_delay(task, 3*HZ); 2181 fallthrough; 2182 case -EADDRINUSE: 2183 case -ENOTCONN: 2184 case -EAGAIN: 2185 case -ETIMEDOUT: 2186 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) && 2187 (task->tk_flags & RPC_TASK_MOVEABLE) && 2188 test_bit(XPRT_REMOVE, &xprt->state)) { 2189 struct rpc_xprt *saved = task->tk_xprt; 2190 struct rpc_xprt_switch *xps; 2191 2192 rcu_read_lock(); 2193 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2194 rcu_read_unlock(); 2195 if (xps->xps_nxprts > 1) { 2196 long value; 2197 2198 xprt_release(task); 2199 value = atomic_long_dec_return(&xprt->queuelen); 2200 if (value == 0) 2201 rpc_xprt_switch_remove_xprt(xps, saved, 2202 true); 2203 xprt_put(saved); 2204 task->tk_xprt = NULL; 2205 task->tk_action = call_start; 2206 } 2207 xprt_switch_put(xps); 2208 if (!task->tk_xprt) 2209 return; 2210 } 2211 goto out_retry; 2212 case -ENOBUFS: 2213 rpc_delay(task, HZ >> 2); 2214 goto out_retry; 2215 } 2216 rpc_call_rpcerror(task, status); 2217 return; 2218 out_next: 2219 task->tk_action = call_transmit; 2220 return; 2221 out_retry: 2222 /* Check for timeouts before looping back to call_bind */ 2223 task->tk_action = call_bind; 2224 rpc_check_timeout(task); 2225 } 2226 2227 /* 2228 * 5. Transmit the RPC request, and wait for reply 2229 */ 2230 static void 2231 call_transmit(struct rpc_task *task) 2232 { 2233 if (rpc_task_transmitted(task)) { 2234 rpc_task_handle_transmitted(task); 2235 return; 2236 } 2237 2238 task->tk_action = call_transmit_status; 2239 if (!xprt_prepare_transmit(task)) 2240 return; 2241 task->tk_status = 0; 2242 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2243 if (!xprt_connected(task->tk_xprt)) { 2244 task->tk_status = -ENOTCONN; 2245 return; 2246 } 2247 xprt_transmit(task); 2248 } 2249 xprt_end_transmit(task); 2250 } 2251 2252 /* 2253 * 5a. Handle cleanup after a transmission 2254 */ 2255 static void 2256 call_transmit_status(struct rpc_task *task) 2257 { 2258 task->tk_action = call_status; 2259 2260 /* 2261 * Common case: success. Force the compiler to put this 2262 * test first. 2263 */ 2264 if (rpc_task_transmitted(task)) { 2265 task->tk_status = 0; 2266 xprt_request_wait_receive(task); 2267 return; 2268 } 2269 2270 switch (task->tk_status) { 2271 default: 2272 break; 2273 case -EBADMSG: 2274 task->tk_status = 0; 2275 task->tk_action = call_encode; 2276 break; 2277 /* 2278 * Special cases: if we've been waiting on the 2279 * socket's write_space() callback, or if the 2280 * socket just returned a connection error, 2281 * then hold onto the transport lock. 2282 */ 2283 case -ENOMEM: 2284 case -ENOBUFS: 2285 rpc_delay(task, HZ>>2); 2286 fallthrough; 2287 case -EBADSLT: 2288 case -EAGAIN: 2289 task->tk_action = call_transmit; 2290 task->tk_status = 0; 2291 break; 2292 case -ECONNREFUSED: 2293 case -EHOSTDOWN: 2294 case -ENETDOWN: 2295 case -EHOSTUNREACH: 2296 case -ENETUNREACH: 2297 case -EPERM: 2298 if (RPC_IS_SOFTCONN(task)) { 2299 if (!task->tk_msg.rpc_proc->p_proc) 2300 trace_xprt_ping(task->tk_xprt, 2301 task->tk_status); 2302 rpc_call_rpcerror(task, task->tk_status); 2303 return; 2304 } 2305 fallthrough; 2306 case -ECONNRESET: 2307 case -ECONNABORTED: 2308 case -EADDRINUSE: 2309 case -ENOTCONN: 2310 case -EPIPE: 2311 task->tk_action = call_bind; 2312 task->tk_status = 0; 2313 break; 2314 } 2315 rpc_check_timeout(task); 2316 } 2317 2318 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2319 static void call_bc_transmit(struct rpc_task *task); 2320 static void call_bc_transmit_status(struct rpc_task *task); 2321 2322 static void 2323 call_bc_encode(struct rpc_task *task) 2324 { 2325 xprt_request_enqueue_transmit(task); 2326 task->tk_action = call_bc_transmit; 2327 } 2328 2329 /* 2330 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2331 * addition, disconnect on connectivity errors. 2332 */ 2333 static void 2334 call_bc_transmit(struct rpc_task *task) 2335 { 2336 task->tk_action = call_bc_transmit_status; 2337 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2338 if (!xprt_prepare_transmit(task)) 2339 return; 2340 task->tk_status = 0; 2341 xprt_transmit(task); 2342 } 2343 xprt_end_transmit(task); 2344 } 2345 2346 static void 2347 call_bc_transmit_status(struct rpc_task *task) 2348 { 2349 struct rpc_rqst *req = task->tk_rqstp; 2350 2351 if (rpc_task_transmitted(task)) 2352 task->tk_status = 0; 2353 2354 switch (task->tk_status) { 2355 case 0: 2356 /* Success */ 2357 case -ENETDOWN: 2358 case -EHOSTDOWN: 2359 case -EHOSTUNREACH: 2360 case -ENETUNREACH: 2361 case -ECONNRESET: 2362 case -ECONNREFUSED: 2363 case -EADDRINUSE: 2364 case -ENOTCONN: 2365 case -EPIPE: 2366 break; 2367 case -ENOMEM: 2368 case -ENOBUFS: 2369 rpc_delay(task, HZ>>2); 2370 fallthrough; 2371 case -EBADSLT: 2372 case -EAGAIN: 2373 task->tk_status = 0; 2374 task->tk_action = call_bc_transmit; 2375 return; 2376 case -ETIMEDOUT: 2377 /* 2378 * Problem reaching the server. Disconnect and let the 2379 * forechannel reestablish the connection. The server will 2380 * have to retransmit the backchannel request and we'll 2381 * reprocess it. Since these ops are idempotent, there's no 2382 * need to cache our reply at this time. 2383 */ 2384 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2385 "error: %d\n", task->tk_status); 2386 xprt_conditional_disconnect(req->rq_xprt, 2387 req->rq_connect_cookie); 2388 break; 2389 default: 2390 /* 2391 * We were unable to reply and will have to drop the 2392 * request. The server should reconnect and retransmit. 2393 */ 2394 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2395 "error: %d\n", task->tk_status); 2396 break; 2397 } 2398 task->tk_action = rpc_exit_task; 2399 } 2400 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2401 2402 /* 2403 * 6. Sort out the RPC call status 2404 */ 2405 static void 2406 call_status(struct rpc_task *task) 2407 { 2408 struct rpc_clnt *clnt = task->tk_client; 2409 int status; 2410 2411 if (!task->tk_msg.rpc_proc->p_proc) 2412 trace_xprt_ping(task->tk_xprt, task->tk_status); 2413 2414 status = task->tk_status; 2415 if (status >= 0) { 2416 task->tk_action = call_decode; 2417 return; 2418 } 2419 2420 trace_rpc_call_status(task); 2421 task->tk_status = 0; 2422 switch(status) { 2423 case -EHOSTDOWN: 2424 case -ENETDOWN: 2425 case -EHOSTUNREACH: 2426 case -ENETUNREACH: 2427 case -EPERM: 2428 if (RPC_IS_SOFTCONN(task)) 2429 goto out_exit; 2430 /* 2431 * Delay any retries for 3 seconds, then handle as if it 2432 * were a timeout. 2433 */ 2434 rpc_delay(task, 3*HZ); 2435 fallthrough; 2436 case -ETIMEDOUT: 2437 break; 2438 case -ECONNREFUSED: 2439 case -ECONNRESET: 2440 case -ECONNABORTED: 2441 case -ENOTCONN: 2442 rpc_force_rebind(clnt); 2443 break; 2444 case -EADDRINUSE: 2445 rpc_delay(task, 3*HZ); 2446 fallthrough; 2447 case -EPIPE: 2448 case -EAGAIN: 2449 break; 2450 case -ENFILE: 2451 case -ENOBUFS: 2452 case -ENOMEM: 2453 rpc_delay(task, HZ>>2); 2454 break; 2455 case -EIO: 2456 /* shutdown or soft timeout */ 2457 goto out_exit; 2458 default: 2459 if (clnt->cl_chatty) 2460 printk("%s: RPC call returned error %d\n", 2461 clnt->cl_program->name, -status); 2462 goto out_exit; 2463 } 2464 task->tk_action = call_encode; 2465 if (status != -ECONNRESET && status != -ECONNABORTED) 2466 rpc_check_timeout(task); 2467 return; 2468 out_exit: 2469 rpc_call_rpcerror(task, status); 2470 } 2471 2472 static bool 2473 rpc_check_connected(const struct rpc_rqst *req) 2474 { 2475 /* No allocated request or transport? return true */ 2476 if (!req || !req->rq_xprt) 2477 return true; 2478 return xprt_connected(req->rq_xprt); 2479 } 2480 2481 static void 2482 rpc_check_timeout(struct rpc_task *task) 2483 { 2484 struct rpc_clnt *clnt = task->tk_client; 2485 2486 if (RPC_SIGNALLED(task)) 2487 return; 2488 2489 if (xprt_adjust_timeout(task->tk_rqstp) == 0) 2490 return; 2491 2492 trace_rpc_timeout_status(task); 2493 task->tk_timeouts++; 2494 2495 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) { 2496 rpc_call_rpcerror(task, -ETIMEDOUT); 2497 return; 2498 } 2499 2500 if (RPC_IS_SOFT(task)) { 2501 /* 2502 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has 2503 * been sent, it should time out only if the transport 2504 * connection gets terminally broken. 2505 */ 2506 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && 2507 rpc_check_connected(task->tk_rqstp)) 2508 return; 2509 2510 if (clnt->cl_chatty) { 2511 pr_notice_ratelimited( 2512 "%s: server %s not responding, timed out\n", 2513 clnt->cl_program->name, 2514 task->tk_xprt->servername); 2515 } 2516 if (task->tk_flags & RPC_TASK_TIMEOUT) 2517 rpc_call_rpcerror(task, -ETIMEDOUT); 2518 else 2519 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT); 2520 return; 2521 } 2522 2523 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2524 task->tk_flags |= RPC_CALL_MAJORSEEN; 2525 if (clnt->cl_chatty) { 2526 pr_notice_ratelimited( 2527 "%s: server %s not responding, still trying\n", 2528 clnt->cl_program->name, 2529 task->tk_xprt->servername); 2530 } 2531 } 2532 rpc_force_rebind(clnt); 2533 /* 2534 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2535 * event? RFC2203 requires the server to drop all such requests. 2536 */ 2537 rpcauth_invalcred(task); 2538 } 2539 2540 /* 2541 * 7. Decode the RPC reply 2542 */ 2543 static void 2544 call_decode(struct rpc_task *task) 2545 { 2546 struct rpc_clnt *clnt = task->tk_client; 2547 struct rpc_rqst *req = task->tk_rqstp; 2548 struct xdr_stream xdr; 2549 int err; 2550 2551 if (!task->tk_msg.rpc_proc->p_decode) { 2552 task->tk_action = rpc_exit_task; 2553 return; 2554 } 2555 2556 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2557 if (clnt->cl_chatty) { 2558 pr_notice_ratelimited("%s: server %s OK\n", 2559 clnt->cl_program->name, 2560 task->tk_xprt->servername); 2561 } 2562 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2563 } 2564 2565 /* 2566 * Did we ever call xprt_complete_rqst()? If not, we should assume 2567 * the message is incomplete. 2568 */ 2569 err = -EAGAIN; 2570 if (!req->rq_reply_bytes_recvd) 2571 goto out; 2572 2573 /* Ensure that we see all writes made by xprt_complete_rqst() 2574 * before it changed req->rq_reply_bytes_recvd. 2575 */ 2576 smp_rmb(); 2577 2578 req->rq_rcv_buf.len = req->rq_private_buf.len; 2579 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf); 2580 2581 /* Check that the softirq receive buffer is valid */ 2582 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2583 sizeof(req->rq_rcv_buf)) != 0); 2584 2585 xdr_init_decode(&xdr, &req->rq_rcv_buf, 2586 req->rq_rcv_buf.head[0].iov_base, req); 2587 err = rpc_decode_header(task, &xdr); 2588 out: 2589 switch (err) { 2590 case 0: 2591 task->tk_action = rpc_exit_task; 2592 task->tk_status = rpcauth_unwrap_resp(task, &xdr); 2593 return; 2594 case -EAGAIN: 2595 task->tk_status = 0; 2596 if (task->tk_client->cl_discrtry) 2597 xprt_conditional_disconnect(req->rq_xprt, 2598 req->rq_connect_cookie); 2599 task->tk_action = call_encode; 2600 rpc_check_timeout(task); 2601 break; 2602 case -EKEYREJECTED: 2603 task->tk_action = call_reserve; 2604 rpc_check_timeout(task); 2605 rpcauth_invalcred(task); 2606 /* Ensure we obtain a new XID if we retry! */ 2607 xprt_release(task); 2608 } 2609 } 2610 2611 static int 2612 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr) 2613 { 2614 struct rpc_clnt *clnt = task->tk_client; 2615 struct rpc_rqst *req = task->tk_rqstp; 2616 __be32 *p; 2617 int error; 2618 2619 error = -EMSGSIZE; 2620 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2); 2621 if (!p) 2622 goto out_fail; 2623 *p++ = req->rq_xid; 2624 *p++ = rpc_call; 2625 *p++ = cpu_to_be32(RPC_VERSION); 2626 *p++ = cpu_to_be32(clnt->cl_prog); 2627 *p++ = cpu_to_be32(clnt->cl_vers); 2628 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc); 2629 2630 error = rpcauth_marshcred(task, xdr); 2631 if (error < 0) 2632 goto out_fail; 2633 return 0; 2634 out_fail: 2635 trace_rpc_bad_callhdr(task); 2636 rpc_call_rpcerror(task, error); 2637 return error; 2638 } 2639 2640 static noinline int 2641 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) 2642 { 2643 struct rpc_clnt *clnt = task->tk_client; 2644 int error; 2645 __be32 *p; 2646 2647 /* RFC-1014 says that the representation of XDR data must be a 2648 * multiple of four bytes 2649 * - if it isn't pointer subtraction in the NFS client may give 2650 * undefined results 2651 */ 2652 if (task->tk_rqstp->rq_rcv_buf.len & 3) 2653 goto out_unparsable; 2654 2655 p = xdr_inline_decode(xdr, 3 * sizeof(*p)); 2656 if (!p) 2657 goto out_unparsable; 2658 p++; /* skip XID */ 2659 if (*p++ != rpc_reply) 2660 goto out_unparsable; 2661 if (*p++ != rpc_msg_accepted) 2662 goto out_msg_denied; 2663 2664 error = rpcauth_checkverf(task, xdr); 2665 if (error) 2666 goto out_verifier; 2667 2668 p = xdr_inline_decode(xdr, sizeof(*p)); 2669 if (!p) 2670 goto out_unparsable; 2671 switch (*p) { 2672 case rpc_success: 2673 return 0; 2674 case rpc_prog_unavail: 2675 trace_rpc__prog_unavail(task); 2676 error = -EPFNOSUPPORT; 2677 goto out_err; 2678 case rpc_prog_mismatch: 2679 trace_rpc__prog_mismatch(task); 2680 error = -EPROTONOSUPPORT; 2681 goto out_err; 2682 case rpc_proc_unavail: 2683 trace_rpc__proc_unavail(task); 2684 error = -EOPNOTSUPP; 2685 goto out_err; 2686 case rpc_garbage_args: 2687 case rpc_system_err: 2688 trace_rpc__garbage_args(task); 2689 error = -EIO; 2690 break; 2691 default: 2692 goto out_unparsable; 2693 } 2694 2695 out_garbage: 2696 clnt->cl_stats->rpcgarbage++; 2697 if (task->tk_garb_retry) { 2698 task->tk_garb_retry--; 2699 task->tk_action = call_encode; 2700 return -EAGAIN; 2701 } 2702 out_err: 2703 rpc_call_rpcerror(task, error); 2704 return error; 2705 2706 out_unparsable: 2707 trace_rpc__unparsable(task); 2708 error = -EIO; 2709 goto out_garbage; 2710 2711 out_verifier: 2712 trace_rpc_bad_verifier(task); 2713 goto out_err; 2714 2715 out_msg_denied: 2716 error = -EACCES; 2717 p = xdr_inline_decode(xdr, sizeof(*p)); 2718 if (!p) 2719 goto out_unparsable; 2720 switch (*p++) { 2721 case rpc_auth_error: 2722 break; 2723 case rpc_mismatch: 2724 trace_rpc__mismatch(task); 2725 error = -EPROTONOSUPPORT; 2726 goto out_err; 2727 default: 2728 goto out_unparsable; 2729 } 2730 2731 p = xdr_inline_decode(xdr, sizeof(*p)); 2732 if (!p) 2733 goto out_unparsable; 2734 switch (*p++) { 2735 case rpc_autherr_rejectedcred: 2736 case rpc_autherr_rejectedverf: 2737 case rpcsec_gsserr_credproblem: 2738 case rpcsec_gsserr_ctxproblem: 2739 if (!task->tk_cred_retry) 2740 break; 2741 task->tk_cred_retry--; 2742 trace_rpc__stale_creds(task); 2743 return -EKEYREJECTED; 2744 case rpc_autherr_badcred: 2745 case rpc_autherr_badverf: 2746 /* possibly garbled cred/verf? */ 2747 if (!task->tk_garb_retry) 2748 break; 2749 task->tk_garb_retry--; 2750 trace_rpc__bad_creds(task); 2751 task->tk_action = call_encode; 2752 return -EAGAIN; 2753 case rpc_autherr_tooweak: 2754 trace_rpc__auth_tooweak(task); 2755 pr_warn("RPC: server %s requires stronger authentication.\n", 2756 task->tk_xprt->servername); 2757 break; 2758 default: 2759 goto out_unparsable; 2760 } 2761 goto out_err; 2762 } 2763 2764 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2765 const void *obj) 2766 { 2767 } 2768 2769 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2770 void *obj) 2771 { 2772 return 0; 2773 } 2774 2775 static const struct rpc_procinfo rpcproc_null = { 2776 .p_encode = rpcproc_encode_null, 2777 .p_decode = rpcproc_decode_null, 2778 }; 2779 2780 static const struct rpc_procinfo rpcproc_null_noreply = { 2781 .p_encode = rpcproc_encode_null, 2782 }; 2783 2784 static void 2785 rpc_null_call_prepare(struct rpc_task *task, void *data) 2786 { 2787 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT; 2788 rpc_call_start(task); 2789 } 2790 2791 static const struct rpc_call_ops rpc_null_ops = { 2792 .rpc_call_prepare = rpc_null_call_prepare, 2793 .rpc_call_done = rpc_default_callback, 2794 }; 2795 2796 static 2797 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2798 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2799 const struct rpc_call_ops *ops, void *data) 2800 { 2801 struct rpc_message msg = { 2802 .rpc_proc = &rpcproc_null, 2803 }; 2804 struct rpc_task_setup task_setup_data = { 2805 .rpc_client = clnt, 2806 .rpc_xprt = xprt, 2807 .rpc_message = &msg, 2808 .rpc_op_cred = cred, 2809 .callback_ops = ops ?: &rpc_null_ops, 2810 .callback_data = data, 2811 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN | 2812 RPC_TASK_NULLCREDS, 2813 }; 2814 2815 return rpc_run_task(&task_setup_data); 2816 } 2817 2818 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2819 { 2820 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2821 } 2822 EXPORT_SYMBOL_GPL(rpc_call_null); 2823 2824 static int rpc_ping(struct rpc_clnt *clnt) 2825 { 2826 struct rpc_task *task; 2827 int status; 2828 2829 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL); 2830 if (IS_ERR(task)) 2831 return PTR_ERR(task); 2832 status = task->tk_status; 2833 rpc_put_task(task); 2834 return status; 2835 } 2836 2837 static int rpc_ping_noreply(struct rpc_clnt *clnt) 2838 { 2839 struct rpc_message msg = { 2840 .rpc_proc = &rpcproc_null_noreply, 2841 }; 2842 struct rpc_task_setup task_setup_data = { 2843 .rpc_client = clnt, 2844 .rpc_message = &msg, 2845 .callback_ops = &rpc_null_ops, 2846 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS, 2847 }; 2848 struct rpc_task *task; 2849 int status; 2850 2851 task = rpc_run_task(&task_setup_data); 2852 if (IS_ERR(task)) 2853 return PTR_ERR(task); 2854 status = task->tk_status; 2855 rpc_put_task(task); 2856 return status; 2857 } 2858 2859 struct rpc_cb_add_xprt_calldata { 2860 struct rpc_xprt_switch *xps; 2861 struct rpc_xprt *xprt; 2862 }; 2863 2864 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2865 { 2866 struct rpc_cb_add_xprt_calldata *data = calldata; 2867 2868 if (task->tk_status == 0) 2869 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2870 } 2871 2872 static void rpc_cb_add_xprt_release(void *calldata) 2873 { 2874 struct rpc_cb_add_xprt_calldata *data = calldata; 2875 2876 xprt_put(data->xprt); 2877 xprt_switch_put(data->xps); 2878 kfree(data); 2879 } 2880 2881 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2882 .rpc_call_prepare = rpc_null_call_prepare, 2883 .rpc_call_done = rpc_cb_add_xprt_done, 2884 .rpc_release = rpc_cb_add_xprt_release, 2885 }; 2886 2887 /** 2888 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2889 * @clnt: pointer to struct rpc_clnt 2890 * @xps: pointer to struct rpc_xprt_switch, 2891 * @xprt: pointer struct rpc_xprt 2892 * @dummy: unused 2893 */ 2894 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2895 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2896 void *dummy) 2897 { 2898 struct rpc_cb_add_xprt_calldata *data; 2899 struct rpc_task *task; 2900 2901 if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) { 2902 rcu_read_lock(); 2903 pr_warn("SUNRPC: reached max allowed number (%d) did not add " 2904 "transport to server: %s\n", clnt->cl_max_connect, 2905 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 2906 rcu_read_unlock(); 2907 return -EINVAL; 2908 } 2909 2910 data = kmalloc(sizeof(*data), GFP_KERNEL); 2911 if (!data) 2912 return -ENOMEM; 2913 data->xps = xprt_switch_get(xps); 2914 data->xprt = xprt_get(xprt); 2915 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) { 2916 rpc_cb_add_xprt_release(data); 2917 goto success; 2918 } 2919 2920 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC, 2921 &rpc_cb_add_xprt_call_ops, data); 2922 if (IS_ERR(task)) 2923 return PTR_ERR(task); 2924 2925 data->xps->xps_nunique_destaddr_xprts++; 2926 rpc_put_task(task); 2927 success: 2928 return 1; 2929 } 2930 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2931 2932 static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt, 2933 struct rpc_xprt *xprt, 2934 struct rpc_add_xprt_test *data) 2935 { 2936 struct rpc_task *task; 2937 int status = -EADDRINUSE; 2938 2939 /* Test the connection */ 2940 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL); 2941 if (IS_ERR(task)) 2942 return PTR_ERR(task); 2943 2944 status = task->tk_status; 2945 rpc_put_task(task); 2946 2947 if (status < 0) 2948 return status; 2949 2950 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ 2951 data->add_xprt_test(clnt, xprt, data->data); 2952 2953 return 0; 2954 } 2955 2956 /** 2957 * rpc_clnt_setup_test_and_add_xprt() 2958 * 2959 * This is an rpc_clnt_add_xprt setup() function which returns 1 so: 2960 * 1) caller of the test function must dereference the rpc_xprt_switch 2961 * and the rpc_xprt. 2962 * 2) test function must call rpc_xprt_switch_add_xprt, usually in 2963 * the rpc_call_done routine. 2964 * 2965 * Upon success (return of 1), the test function adds the new 2966 * transport to the rpc_clnt xprt switch 2967 * 2968 * @clnt: struct rpc_clnt to get the new transport 2969 * @xps: the rpc_xprt_switch to hold the new transport 2970 * @xprt: the rpc_xprt to test 2971 * @data: a struct rpc_add_xprt_test pointer that holds the test function 2972 * and test function call data 2973 */ 2974 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, 2975 struct rpc_xprt_switch *xps, 2976 struct rpc_xprt *xprt, 2977 void *data) 2978 { 2979 int status = -EADDRINUSE; 2980 2981 xprt = xprt_get(xprt); 2982 xprt_switch_get(xps); 2983 2984 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) 2985 goto out_err; 2986 2987 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 2988 if (status < 0) 2989 goto out_err; 2990 2991 status = 1; 2992 out_err: 2993 xprt_put(xprt); 2994 xprt_switch_put(xps); 2995 if (status < 0) 2996 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not " 2997 "added\n", status, 2998 xprt->address_strings[RPC_DISPLAY_ADDR]); 2999 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ 3000 return status; 3001 } 3002 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); 3003 3004 /** 3005 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 3006 * @clnt: pointer to struct rpc_clnt 3007 * @xprtargs: pointer to struct xprt_create 3008 * @setup: callback to test and/or set up the connection 3009 * @data: pointer to setup function data 3010 * 3011 * Creates a new transport using the parameters set in args and 3012 * adds it to clnt. 3013 * If ping is set, then test that connectivity succeeds before 3014 * adding the new transport. 3015 * 3016 */ 3017 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 3018 struct xprt_create *xprtargs, 3019 int (*setup)(struct rpc_clnt *, 3020 struct rpc_xprt_switch *, 3021 struct rpc_xprt *, 3022 void *), 3023 void *data) 3024 { 3025 struct rpc_xprt_switch *xps; 3026 struct rpc_xprt *xprt; 3027 unsigned long connect_timeout; 3028 unsigned long reconnect_timeout; 3029 unsigned char resvport, reuseport; 3030 int ret = 0, ident; 3031 3032 rcu_read_lock(); 3033 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3034 xprt = xprt_iter_xprt(&clnt->cl_xpi); 3035 if (xps == NULL || xprt == NULL) { 3036 rcu_read_unlock(); 3037 xprt_switch_put(xps); 3038 return -EAGAIN; 3039 } 3040 resvport = xprt->resvport; 3041 reuseport = xprt->reuseport; 3042 connect_timeout = xprt->connect_timeout; 3043 reconnect_timeout = xprt->max_reconnect_timeout; 3044 ident = xprt->xprt_class->ident; 3045 rcu_read_unlock(); 3046 3047 if (!xprtargs->ident) 3048 xprtargs->ident = ident; 3049 xprt = xprt_create_transport(xprtargs); 3050 if (IS_ERR(xprt)) { 3051 ret = PTR_ERR(xprt); 3052 goto out_put_switch; 3053 } 3054 xprt->resvport = resvport; 3055 xprt->reuseport = reuseport; 3056 if (xprt->ops->set_connect_timeout != NULL) 3057 xprt->ops->set_connect_timeout(xprt, 3058 connect_timeout, 3059 reconnect_timeout); 3060 3061 rpc_xprt_switch_set_roundrobin(xps); 3062 if (setup) { 3063 ret = setup(clnt, xps, xprt, data); 3064 if (ret != 0) 3065 goto out_put_xprt; 3066 } 3067 rpc_xprt_switch_add_xprt(xps, xprt); 3068 out_put_xprt: 3069 xprt_put(xprt); 3070 out_put_switch: 3071 xprt_switch_put(xps); 3072 return ret; 3073 } 3074 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 3075 3076 static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt, 3077 struct rpc_xprt *xprt, 3078 struct rpc_add_xprt_test *data) 3079 { 3080 struct rpc_xprt_switch *xps; 3081 struct rpc_xprt *main_xprt; 3082 int status = 0; 3083 3084 xprt_get(xprt); 3085 3086 rcu_read_lock(); 3087 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3088 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3089 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3090 (struct sockaddr *)&main_xprt->addr); 3091 rcu_read_unlock(); 3092 xprt_put(main_xprt); 3093 if (status || !test_bit(XPRT_OFFLINE, &xprt->state)) 3094 goto out; 3095 3096 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3097 out: 3098 xprt_put(xprt); 3099 xprt_switch_put(xps); 3100 return status; 3101 } 3102 3103 /* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking 3104 * @clnt rpc_clnt structure 3105 * 3106 * For each offlined transport found in the rpc_clnt structure call 3107 * the function rpc_xprt_probe_trunked() which will determine if this 3108 * transport still belongs to the trunking group. 3109 */ 3110 void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt, 3111 struct rpc_add_xprt_test *data) 3112 { 3113 struct rpc_xprt_iter xpi; 3114 int ret; 3115 3116 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi); 3117 if (ret) 3118 return; 3119 for (;;) { 3120 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 3121 3122 if (!xprt) 3123 break; 3124 ret = rpc_xprt_probe_trunked(clnt, xprt, data); 3125 xprt_put(xprt); 3126 if (ret < 0) 3127 break; 3128 xprt_iter_rewind(&xpi); 3129 } 3130 xprt_iter_destroy(&xpi); 3131 } 3132 EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts); 3133 3134 static int rpc_xprt_offline(struct rpc_clnt *clnt, 3135 struct rpc_xprt *xprt, 3136 void *data) 3137 { 3138 struct rpc_xprt *main_xprt; 3139 struct rpc_xprt_switch *xps; 3140 int err = 0; 3141 3142 xprt_get(xprt); 3143 3144 rcu_read_lock(); 3145 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3146 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3147 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3148 (struct sockaddr *)&main_xprt->addr); 3149 rcu_read_unlock(); 3150 xprt_put(main_xprt); 3151 if (err) 3152 goto out; 3153 3154 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) { 3155 err = -EINTR; 3156 goto out; 3157 } 3158 xprt_set_offline_locked(xprt, xps); 3159 3160 xprt_release_write(xprt, NULL); 3161 out: 3162 xprt_put(xprt); 3163 xprt_switch_put(xps); 3164 return err; 3165 } 3166 3167 /* rpc_clnt_manage_trunked_xprts -- offline trunked transports 3168 * @clnt rpc_clnt structure 3169 * 3170 * For each active transport found in the rpc_clnt structure call 3171 * the function rpc_xprt_offline() which will identify trunked transports 3172 * and will mark them offline. 3173 */ 3174 void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt) 3175 { 3176 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL); 3177 } 3178 EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts); 3179 3180 struct connect_timeout_data { 3181 unsigned long connect_timeout; 3182 unsigned long reconnect_timeout; 3183 }; 3184 3185 static int 3186 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, 3187 struct rpc_xprt *xprt, 3188 void *data) 3189 { 3190 struct connect_timeout_data *timeo = data; 3191 3192 if (xprt->ops->set_connect_timeout) 3193 xprt->ops->set_connect_timeout(xprt, 3194 timeo->connect_timeout, 3195 timeo->reconnect_timeout); 3196 return 0; 3197 } 3198 3199 void 3200 rpc_set_connect_timeout(struct rpc_clnt *clnt, 3201 unsigned long connect_timeout, 3202 unsigned long reconnect_timeout) 3203 { 3204 struct connect_timeout_data timeout = { 3205 .connect_timeout = connect_timeout, 3206 .reconnect_timeout = reconnect_timeout, 3207 }; 3208 rpc_clnt_iterate_for_each_xprt(clnt, 3209 rpc_xprt_set_connect_timeout, 3210 &timeout); 3211 } 3212 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); 3213 3214 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt) 3215 { 3216 rcu_read_lock(); 3217 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3218 rcu_read_unlock(); 3219 } 3220 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put); 3221 3222 void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3223 { 3224 struct rpc_xprt_switch *xps; 3225 3226 rcu_read_lock(); 3227 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3228 rcu_read_unlock(); 3229 xprt_set_online_locked(xprt, xps); 3230 } 3231 3232 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3233 { 3234 if (rpc_clnt_xprt_switch_has_addr(clnt, 3235 (const struct sockaddr *)&xprt->addr)) { 3236 return rpc_clnt_xprt_set_online(clnt, xprt); 3237 } 3238 rcu_read_lock(); 3239 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3240 xprt); 3241 rcu_read_unlock(); 3242 } 3243 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); 3244 3245 void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3246 { 3247 struct rpc_xprt_switch *xps; 3248 3249 rcu_read_lock(); 3250 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3251 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3252 xprt, 0); 3253 xps->xps_nunique_destaddr_xprts--; 3254 rcu_read_unlock(); 3255 } 3256 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt); 3257 3258 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, 3259 const struct sockaddr *sap) 3260 { 3261 struct rpc_xprt_switch *xps; 3262 bool ret; 3263 3264 rcu_read_lock(); 3265 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3266 ret = rpc_xprt_switch_has_addr(xps, sap); 3267 rcu_read_unlock(); 3268 return ret; 3269 } 3270 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); 3271 3272 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3273 static void rpc_show_header(void) 3274 { 3275 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 3276 "-timeout ---ops--\n"); 3277 } 3278 3279 static void rpc_show_task(const struct rpc_clnt *clnt, 3280 const struct rpc_task *task) 3281 { 3282 const char *rpc_waitq = "none"; 3283 3284 if (RPC_IS_QUEUED(task)) 3285 rpc_waitq = rpc_qname(task->tk_waitqueue); 3286 3287 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 3288 task->tk_pid, task->tk_flags, task->tk_status, 3289 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops, 3290 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 3291 task->tk_action, rpc_waitq); 3292 } 3293 3294 void rpc_show_tasks(struct net *net) 3295 { 3296 struct rpc_clnt *clnt; 3297 struct rpc_task *task; 3298 int header = 0; 3299 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 3300 3301 spin_lock(&sn->rpc_client_lock); 3302 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 3303 spin_lock(&clnt->cl_lock); 3304 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 3305 if (!header) { 3306 rpc_show_header(); 3307 header++; 3308 } 3309 rpc_show_task(clnt, task); 3310 } 3311 spin_unlock(&clnt->cl_lock); 3312 } 3313 spin_unlock(&sn->rpc_client_lock); 3314 } 3315 #endif 3316 3317 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 3318 static int 3319 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 3320 struct rpc_xprt *xprt, 3321 void *dummy) 3322 { 3323 return xprt_enable_swap(xprt); 3324 } 3325 3326 int 3327 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 3328 { 3329 while (clnt != clnt->cl_parent) 3330 clnt = clnt->cl_parent; 3331 if (atomic_inc_return(&clnt->cl_swapper) == 1) 3332 return rpc_clnt_iterate_for_each_xprt(clnt, 3333 rpc_clnt_swap_activate_callback, NULL); 3334 return 0; 3335 } 3336 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 3337 3338 static int 3339 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 3340 struct rpc_xprt *xprt, 3341 void *dummy) 3342 { 3343 xprt_disable_swap(xprt); 3344 return 0; 3345 } 3346 3347 void 3348 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 3349 { 3350 while (clnt != clnt->cl_parent) 3351 clnt = clnt->cl_parent; 3352 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 3353 rpc_clnt_iterate_for_each_xprt(clnt, 3354 rpc_clnt_swap_deactivate_callback, NULL); 3355 } 3356 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 3357 #endif /* CONFIG_SUNRPC_SWAP */ 3358