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_simple_get(&rpc_clids, 0, 0, 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_simple_remove(&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 * Properly shut down an RPC client, terminating all outstanding 878 * requests. 879 */ 880 void rpc_shutdown_client(struct rpc_clnt *clnt) 881 { 882 might_sleep(); 883 884 trace_rpc_clnt_shutdown(clnt); 885 886 while (!list_empty(&clnt->cl_tasks)) { 887 rpc_killall_tasks(clnt); 888 wait_event_timeout(destroy_wait, 889 list_empty(&clnt->cl_tasks), 1*HZ); 890 } 891 892 rpc_release_client(clnt); 893 } 894 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 895 896 /* 897 * Free an RPC client 898 */ 899 static void rpc_free_client_work(struct work_struct *work) 900 { 901 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work); 902 903 trace_rpc_clnt_free(clnt); 904 905 /* These might block on processes that might allocate memory, 906 * so they cannot be called in rpciod, so they are handled separately 907 * here. 908 */ 909 rpc_sysfs_client_destroy(clnt); 910 rpc_clnt_debugfs_unregister(clnt); 911 rpc_free_clid(clnt); 912 rpc_clnt_remove_pipedir(clnt); 913 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 914 915 kfree(clnt); 916 rpciod_down(); 917 } 918 static struct rpc_clnt * 919 rpc_free_client(struct rpc_clnt *clnt) 920 { 921 struct rpc_clnt *parent = NULL; 922 923 trace_rpc_clnt_release(clnt); 924 if (clnt->cl_parent != clnt) 925 parent = clnt->cl_parent; 926 rpc_unregister_client(clnt); 927 rpc_free_iostats(clnt->cl_metrics); 928 clnt->cl_metrics = NULL; 929 xprt_iter_destroy(&clnt->cl_xpi); 930 put_cred(clnt->cl_cred); 931 932 INIT_WORK(&clnt->cl_work, rpc_free_client_work); 933 schedule_work(&clnt->cl_work); 934 return parent; 935 } 936 937 /* 938 * Free an RPC client 939 */ 940 static struct rpc_clnt * 941 rpc_free_auth(struct rpc_clnt *clnt) 942 { 943 /* 944 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 945 * release remaining GSS contexts. This mechanism ensures 946 * that it can do so safely. 947 */ 948 if (clnt->cl_auth != NULL) { 949 rpcauth_release(clnt->cl_auth); 950 clnt->cl_auth = NULL; 951 } 952 if (refcount_dec_and_test(&clnt->cl_count)) 953 return rpc_free_client(clnt); 954 return NULL; 955 } 956 957 /* 958 * Release reference to the RPC client 959 */ 960 void 961 rpc_release_client(struct rpc_clnt *clnt) 962 { 963 do { 964 if (list_empty(&clnt->cl_tasks)) 965 wake_up(&destroy_wait); 966 if (refcount_dec_not_one(&clnt->cl_count)) 967 break; 968 clnt = rpc_free_auth(clnt); 969 } while (clnt != NULL); 970 } 971 EXPORT_SYMBOL_GPL(rpc_release_client); 972 973 /** 974 * rpc_bind_new_program - bind a new RPC program to an existing client 975 * @old: old rpc_client 976 * @program: rpc program to set 977 * @vers: rpc program version 978 * 979 * Clones the rpc client and sets up a new RPC program. This is mainly 980 * of use for enabling different RPC programs to share the same transport. 981 * The Sun NFSv2/v3 ACL protocol can do this. 982 */ 983 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 984 const struct rpc_program *program, 985 u32 vers) 986 { 987 struct rpc_create_args args = { 988 .program = program, 989 .prognumber = program->number, 990 .version = vers, 991 .authflavor = old->cl_auth->au_flavor, 992 .cred = old->cl_cred, 993 }; 994 struct rpc_clnt *clnt; 995 int err; 996 997 clnt = __rpc_clone_client(&args, old); 998 if (IS_ERR(clnt)) 999 goto out; 1000 err = rpc_ping(clnt); 1001 if (err != 0) { 1002 rpc_shutdown_client(clnt); 1003 clnt = ERR_PTR(err); 1004 } 1005 out: 1006 return clnt; 1007 } 1008 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 1009 1010 struct rpc_xprt * 1011 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1012 { 1013 struct rpc_xprt_switch *xps; 1014 1015 if (!xprt) 1016 return NULL; 1017 rcu_read_lock(); 1018 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1019 atomic_long_inc(&xps->xps_queuelen); 1020 rcu_read_unlock(); 1021 atomic_long_inc(&xprt->queuelen); 1022 1023 return xprt; 1024 } 1025 1026 static void 1027 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1028 { 1029 struct rpc_xprt_switch *xps; 1030 1031 atomic_long_dec(&xprt->queuelen); 1032 rcu_read_lock(); 1033 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1034 atomic_long_dec(&xps->xps_queuelen); 1035 rcu_read_unlock(); 1036 1037 xprt_put(xprt); 1038 } 1039 1040 void rpc_task_release_transport(struct rpc_task *task) 1041 { 1042 struct rpc_xprt *xprt = task->tk_xprt; 1043 1044 if (xprt) { 1045 task->tk_xprt = NULL; 1046 if (task->tk_client) 1047 rpc_task_release_xprt(task->tk_client, xprt); 1048 else 1049 xprt_put(xprt); 1050 } 1051 } 1052 EXPORT_SYMBOL_GPL(rpc_task_release_transport); 1053 1054 void rpc_task_release_client(struct rpc_task *task) 1055 { 1056 struct rpc_clnt *clnt = task->tk_client; 1057 1058 rpc_task_release_transport(task); 1059 if (clnt != NULL) { 1060 /* Remove from client task list */ 1061 spin_lock(&clnt->cl_lock); 1062 list_del(&task->tk_task); 1063 spin_unlock(&clnt->cl_lock); 1064 task->tk_client = NULL; 1065 1066 rpc_release_client(clnt); 1067 } 1068 } 1069 1070 static struct rpc_xprt * 1071 rpc_task_get_first_xprt(struct rpc_clnt *clnt) 1072 { 1073 struct rpc_xprt *xprt; 1074 1075 rcu_read_lock(); 1076 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 1077 rcu_read_unlock(); 1078 return rpc_task_get_xprt(clnt, xprt); 1079 } 1080 1081 static struct rpc_xprt * 1082 rpc_task_get_next_xprt(struct rpc_clnt *clnt) 1083 { 1084 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi)); 1085 } 1086 1087 static 1088 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) 1089 { 1090 if (task->tk_xprt) { 1091 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) && 1092 (task->tk_flags & RPC_TASK_MOVEABLE))) 1093 return; 1094 xprt_release(task); 1095 xprt_put(task->tk_xprt); 1096 } 1097 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) 1098 task->tk_xprt = rpc_task_get_first_xprt(clnt); 1099 else 1100 task->tk_xprt = rpc_task_get_next_xprt(clnt); 1101 } 1102 1103 static 1104 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 1105 { 1106 rpc_task_set_transport(task, clnt); 1107 task->tk_client = clnt; 1108 refcount_inc(&clnt->cl_count); 1109 if (clnt->cl_softrtry) 1110 task->tk_flags |= RPC_TASK_SOFT; 1111 if (clnt->cl_softerr) 1112 task->tk_flags |= RPC_TASK_TIMEOUT; 1113 if (clnt->cl_noretranstimeo) 1114 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1115 /* Add to the client's list of all tasks */ 1116 spin_lock(&clnt->cl_lock); 1117 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1118 spin_unlock(&clnt->cl_lock); 1119 } 1120 1121 static void 1122 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1123 { 1124 if (msg != NULL) { 1125 task->tk_msg.rpc_proc = msg->rpc_proc; 1126 task->tk_msg.rpc_argp = msg->rpc_argp; 1127 task->tk_msg.rpc_resp = msg->rpc_resp; 1128 task->tk_msg.rpc_cred = msg->rpc_cred; 1129 if (!(task->tk_flags & RPC_TASK_CRED_NOREF)) 1130 get_cred(task->tk_msg.rpc_cred); 1131 } 1132 } 1133 1134 /* 1135 * Default callback for async RPC calls 1136 */ 1137 static void 1138 rpc_default_callback(struct rpc_task *task, void *data) 1139 { 1140 } 1141 1142 static const struct rpc_call_ops rpc_default_ops = { 1143 .rpc_call_done = rpc_default_callback, 1144 }; 1145 1146 /** 1147 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1148 * @task_setup_data: pointer to task initialisation data 1149 */ 1150 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1151 { 1152 struct rpc_task *task; 1153 1154 task = rpc_new_task(task_setup_data); 1155 if (IS_ERR(task)) 1156 return task; 1157 1158 if (!RPC_IS_ASYNC(task)) 1159 task->tk_flags |= RPC_TASK_CRED_NOREF; 1160 1161 rpc_task_set_client(task, task_setup_data->rpc_client); 1162 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1163 1164 if (task->tk_action == NULL) 1165 rpc_call_start(task); 1166 1167 atomic_inc(&task->tk_count); 1168 rpc_execute(task); 1169 return task; 1170 } 1171 EXPORT_SYMBOL_GPL(rpc_run_task); 1172 1173 /** 1174 * rpc_call_sync - Perform a synchronous RPC call 1175 * @clnt: pointer to RPC client 1176 * @msg: RPC call parameters 1177 * @flags: RPC call flags 1178 */ 1179 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1180 { 1181 struct rpc_task *task; 1182 struct rpc_task_setup task_setup_data = { 1183 .rpc_client = clnt, 1184 .rpc_message = msg, 1185 .callback_ops = &rpc_default_ops, 1186 .flags = flags, 1187 }; 1188 int status; 1189 1190 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1191 if (flags & RPC_TASK_ASYNC) { 1192 rpc_release_calldata(task_setup_data.callback_ops, 1193 task_setup_data.callback_data); 1194 return -EINVAL; 1195 } 1196 1197 task = rpc_run_task(&task_setup_data); 1198 if (IS_ERR(task)) 1199 return PTR_ERR(task); 1200 status = task->tk_status; 1201 rpc_put_task(task); 1202 return status; 1203 } 1204 EXPORT_SYMBOL_GPL(rpc_call_sync); 1205 1206 /** 1207 * rpc_call_async - Perform an asynchronous RPC call 1208 * @clnt: pointer to RPC client 1209 * @msg: RPC call parameters 1210 * @flags: RPC call flags 1211 * @tk_ops: RPC call ops 1212 * @data: user call data 1213 */ 1214 int 1215 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1216 const struct rpc_call_ops *tk_ops, void *data) 1217 { 1218 struct rpc_task *task; 1219 struct rpc_task_setup task_setup_data = { 1220 .rpc_client = clnt, 1221 .rpc_message = msg, 1222 .callback_ops = tk_ops, 1223 .callback_data = data, 1224 .flags = flags|RPC_TASK_ASYNC, 1225 }; 1226 1227 task = rpc_run_task(&task_setup_data); 1228 if (IS_ERR(task)) 1229 return PTR_ERR(task); 1230 rpc_put_task(task); 1231 return 0; 1232 } 1233 EXPORT_SYMBOL_GPL(rpc_call_async); 1234 1235 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1236 static void call_bc_encode(struct rpc_task *task); 1237 1238 /** 1239 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1240 * rpc_execute against it 1241 * @req: RPC request 1242 */ 1243 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) 1244 { 1245 struct rpc_task *task; 1246 struct rpc_task_setup task_setup_data = { 1247 .callback_ops = &rpc_default_ops, 1248 .flags = RPC_TASK_SOFTCONN | 1249 RPC_TASK_NO_RETRANS_TIMEOUT, 1250 }; 1251 1252 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1253 /* 1254 * Create an rpc_task to send the data 1255 */ 1256 task = rpc_new_task(&task_setup_data); 1257 if (IS_ERR(task)) { 1258 xprt_free_bc_request(req); 1259 return task; 1260 } 1261 1262 xprt_init_bc_request(req, task); 1263 1264 task->tk_action = call_bc_encode; 1265 atomic_inc(&task->tk_count); 1266 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1267 rpc_execute(task); 1268 1269 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1270 return task; 1271 } 1272 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1273 1274 /** 1275 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages 1276 * @req: RPC request to prepare 1277 * @pages: vector of struct page pointers 1278 * @base: offset in first page where receive should start, in bytes 1279 * @len: expected size of the upper layer data payload, in bytes 1280 * @hdrsize: expected size of upper layer reply header, in XDR words 1281 * 1282 */ 1283 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, 1284 unsigned int base, unsigned int len, 1285 unsigned int hdrsize) 1286 { 1287 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; 1288 1289 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); 1290 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); 1291 } 1292 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages); 1293 1294 void 1295 rpc_call_start(struct rpc_task *task) 1296 { 1297 task->tk_action = call_start; 1298 } 1299 EXPORT_SYMBOL_GPL(rpc_call_start); 1300 1301 /** 1302 * rpc_peeraddr - extract remote peer address from clnt's xprt 1303 * @clnt: RPC client structure 1304 * @buf: target buffer 1305 * @bufsize: length of target buffer 1306 * 1307 * Returns the number of bytes that are actually in the stored address. 1308 */ 1309 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1310 { 1311 size_t bytes; 1312 struct rpc_xprt *xprt; 1313 1314 rcu_read_lock(); 1315 xprt = rcu_dereference(clnt->cl_xprt); 1316 1317 bytes = xprt->addrlen; 1318 if (bytes > bufsize) 1319 bytes = bufsize; 1320 memcpy(buf, &xprt->addr, bytes); 1321 rcu_read_unlock(); 1322 1323 return bytes; 1324 } 1325 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1326 1327 /** 1328 * rpc_peeraddr2str - return remote peer address in printable format 1329 * @clnt: RPC client structure 1330 * @format: address format 1331 * 1332 * NB: the lifetime of the memory referenced by the returned pointer is 1333 * the same as the rpc_xprt itself. As long as the caller uses this 1334 * pointer, it must hold the RCU read lock. 1335 */ 1336 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1337 enum rpc_display_format_t format) 1338 { 1339 struct rpc_xprt *xprt; 1340 1341 xprt = rcu_dereference(clnt->cl_xprt); 1342 1343 if (xprt->address_strings[format] != NULL) 1344 return xprt->address_strings[format]; 1345 else 1346 return "unprintable"; 1347 } 1348 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1349 1350 static const struct sockaddr_in rpc_inaddr_loopback = { 1351 .sin_family = AF_INET, 1352 .sin_addr.s_addr = htonl(INADDR_ANY), 1353 }; 1354 1355 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1356 .sin6_family = AF_INET6, 1357 .sin6_addr = IN6ADDR_ANY_INIT, 1358 }; 1359 1360 /* 1361 * Try a getsockname() on a connected datagram socket. Using a 1362 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1363 * This conserves the ephemeral port number space. 1364 * 1365 * Returns zero and fills in "buf" if successful; otherwise, a 1366 * negative errno is returned. 1367 */ 1368 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1369 struct sockaddr *buf) 1370 { 1371 struct socket *sock; 1372 int err; 1373 1374 err = __sock_create(net, sap->sa_family, 1375 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1376 if (err < 0) { 1377 dprintk("RPC: can't create UDP socket (%d)\n", err); 1378 goto out; 1379 } 1380 1381 switch (sap->sa_family) { 1382 case AF_INET: 1383 err = kernel_bind(sock, 1384 (struct sockaddr *)&rpc_inaddr_loopback, 1385 sizeof(rpc_inaddr_loopback)); 1386 break; 1387 case AF_INET6: 1388 err = kernel_bind(sock, 1389 (struct sockaddr *)&rpc_in6addr_loopback, 1390 sizeof(rpc_in6addr_loopback)); 1391 break; 1392 default: 1393 err = -EAFNOSUPPORT; 1394 goto out; 1395 } 1396 if (err < 0) { 1397 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1398 goto out_release; 1399 } 1400 1401 err = kernel_connect(sock, sap, salen, 0); 1402 if (err < 0) { 1403 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1404 goto out_release; 1405 } 1406 1407 err = kernel_getsockname(sock, buf); 1408 if (err < 0) { 1409 dprintk("RPC: getsockname failed (%d)\n", err); 1410 goto out_release; 1411 } 1412 1413 err = 0; 1414 if (buf->sa_family == AF_INET6) { 1415 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1416 sin6->sin6_scope_id = 0; 1417 } 1418 dprintk("RPC: %s succeeded\n", __func__); 1419 1420 out_release: 1421 sock_release(sock); 1422 out: 1423 return err; 1424 } 1425 1426 /* 1427 * Scraping a connected socket failed, so we don't have a useable 1428 * local address. Fallback: generate an address that will prevent 1429 * the server from calling us back. 1430 * 1431 * Returns zero and fills in "buf" if successful; otherwise, a 1432 * negative errno is returned. 1433 */ 1434 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1435 { 1436 switch (family) { 1437 case AF_INET: 1438 if (buflen < sizeof(rpc_inaddr_loopback)) 1439 return -EINVAL; 1440 memcpy(buf, &rpc_inaddr_loopback, 1441 sizeof(rpc_inaddr_loopback)); 1442 break; 1443 case AF_INET6: 1444 if (buflen < sizeof(rpc_in6addr_loopback)) 1445 return -EINVAL; 1446 memcpy(buf, &rpc_in6addr_loopback, 1447 sizeof(rpc_in6addr_loopback)); 1448 break; 1449 default: 1450 dprintk("RPC: %s: address family not supported\n", 1451 __func__); 1452 return -EAFNOSUPPORT; 1453 } 1454 dprintk("RPC: %s: succeeded\n", __func__); 1455 return 0; 1456 } 1457 1458 /** 1459 * rpc_localaddr - discover local endpoint address for an RPC client 1460 * @clnt: RPC client structure 1461 * @buf: target buffer 1462 * @buflen: size of target buffer, in bytes 1463 * 1464 * Returns zero and fills in "buf" and "buflen" if successful; 1465 * otherwise, a negative errno is returned. 1466 * 1467 * This works even if the underlying transport is not currently connected, 1468 * or if the upper layer never previously provided a source address. 1469 * 1470 * The result of this function call is transient: multiple calls in 1471 * succession may give different results, depending on how local 1472 * networking configuration changes over time. 1473 */ 1474 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1475 { 1476 struct sockaddr_storage address; 1477 struct sockaddr *sap = (struct sockaddr *)&address; 1478 struct rpc_xprt *xprt; 1479 struct net *net; 1480 size_t salen; 1481 int err; 1482 1483 rcu_read_lock(); 1484 xprt = rcu_dereference(clnt->cl_xprt); 1485 salen = xprt->addrlen; 1486 memcpy(sap, &xprt->addr, salen); 1487 net = get_net(xprt->xprt_net); 1488 rcu_read_unlock(); 1489 1490 rpc_set_port(sap, 0); 1491 err = rpc_sockname(net, sap, salen, buf); 1492 put_net(net); 1493 if (err != 0) 1494 /* Couldn't discover local address, return ANYADDR */ 1495 return rpc_anyaddr(sap->sa_family, buf, buflen); 1496 return 0; 1497 } 1498 EXPORT_SYMBOL_GPL(rpc_localaddr); 1499 1500 void 1501 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1502 { 1503 struct rpc_xprt *xprt; 1504 1505 rcu_read_lock(); 1506 xprt = rcu_dereference(clnt->cl_xprt); 1507 if (xprt->ops->set_buffer_size) 1508 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1509 rcu_read_unlock(); 1510 } 1511 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1512 1513 /** 1514 * rpc_net_ns - Get the network namespace for this RPC client 1515 * @clnt: RPC client to query 1516 * 1517 */ 1518 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1519 { 1520 struct net *ret; 1521 1522 rcu_read_lock(); 1523 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1524 rcu_read_unlock(); 1525 return ret; 1526 } 1527 EXPORT_SYMBOL_GPL(rpc_net_ns); 1528 1529 /** 1530 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1531 * @clnt: RPC client to query 1532 * 1533 * For stream transports, this is one RPC record fragment (see RFC 1534 * 1831), as we don't support multi-record requests yet. For datagram 1535 * transports, this is the size of an IP packet minus the IP, UDP, and 1536 * RPC header sizes. 1537 */ 1538 size_t rpc_max_payload(struct rpc_clnt *clnt) 1539 { 1540 size_t ret; 1541 1542 rcu_read_lock(); 1543 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1544 rcu_read_unlock(); 1545 return ret; 1546 } 1547 EXPORT_SYMBOL_GPL(rpc_max_payload); 1548 1549 /** 1550 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1551 * @clnt: RPC client to query 1552 */ 1553 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1554 { 1555 struct rpc_xprt *xprt; 1556 size_t ret; 1557 1558 rcu_read_lock(); 1559 xprt = rcu_dereference(clnt->cl_xprt); 1560 ret = xprt->ops->bc_maxpayload(xprt); 1561 rcu_read_unlock(); 1562 return ret; 1563 } 1564 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1565 1566 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt) 1567 { 1568 struct rpc_xprt *xprt; 1569 unsigned int ret; 1570 1571 rcu_read_lock(); 1572 xprt = rcu_dereference(clnt->cl_xprt); 1573 ret = xprt->ops->bc_num_slots(xprt); 1574 rcu_read_unlock(); 1575 return ret; 1576 } 1577 EXPORT_SYMBOL_GPL(rpc_num_bc_slots); 1578 1579 /** 1580 * rpc_force_rebind - force transport to check that remote port is unchanged 1581 * @clnt: client to rebind 1582 * 1583 */ 1584 void rpc_force_rebind(struct rpc_clnt *clnt) 1585 { 1586 if (clnt->cl_autobind) { 1587 rcu_read_lock(); 1588 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1589 rcu_read_unlock(); 1590 } 1591 } 1592 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1593 1594 static int 1595 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *)) 1596 { 1597 task->tk_status = 0; 1598 task->tk_rpc_status = 0; 1599 task->tk_action = action; 1600 return 1; 1601 } 1602 1603 /* 1604 * Restart an (async) RPC call. Usually called from within the 1605 * exit handler. 1606 */ 1607 int 1608 rpc_restart_call(struct rpc_task *task) 1609 { 1610 return __rpc_restart_call(task, call_start); 1611 } 1612 EXPORT_SYMBOL_GPL(rpc_restart_call); 1613 1614 /* 1615 * Restart an (async) RPC call from the call_prepare state. 1616 * Usually called from within the exit handler. 1617 */ 1618 int 1619 rpc_restart_call_prepare(struct rpc_task *task) 1620 { 1621 if (task->tk_ops->rpc_call_prepare != NULL) 1622 return __rpc_restart_call(task, rpc_prepare_task); 1623 return rpc_restart_call(task); 1624 } 1625 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1626 1627 const char 1628 *rpc_proc_name(const struct rpc_task *task) 1629 { 1630 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1631 1632 if (proc) { 1633 if (proc->p_name) 1634 return proc->p_name; 1635 else 1636 return "NULL"; 1637 } else 1638 return "no proc"; 1639 } 1640 1641 static void 1642 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status) 1643 { 1644 trace_rpc_call_rpcerror(task, tk_status, rpc_status); 1645 task->tk_rpc_status = rpc_status; 1646 rpc_exit(task, tk_status); 1647 } 1648 1649 static void 1650 rpc_call_rpcerror(struct rpc_task *task, int status) 1651 { 1652 __rpc_call_rpcerror(task, status, status); 1653 } 1654 1655 /* 1656 * 0. Initial state 1657 * 1658 * Other FSM states can be visited zero or more times, but 1659 * this state is visited exactly once for each RPC. 1660 */ 1661 static void 1662 call_start(struct rpc_task *task) 1663 { 1664 struct rpc_clnt *clnt = task->tk_client; 1665 int idx = task->tk_msg.rpc_proc->p_statidx; 1666 1667 trace_rpc_request(task); 1668 1669 /* Increment call count (version might not be valid for ping) */ 1670 if (clnt->cl_program->version[clnt->cl_vers]) 1671 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; 1672 clnt->cl_stats->rpccnt++; 1673 task->tk_action = call_reserve; 1674 rpc_task_set_transport(task, clnt); 1675 } 1676 1677 /* 1678 * 1. Reserve an RPC call slot 1679 */ 1680 static void 1681 call_reserve(struct rpc_task *task) 1682 { 1683 task->tk_status = 0; 1684 task->tk_action = call_reserveresult; 1685 xprt_reserve(task); 1686 } 1687 1688 static void call_retry_reserve(struct rpc_task *task); 1689 1690 /* 1691 * 1b. Grok the result of xprt_reserve() 1692 */ 1693 static void 1694 call_reserveresult(struct rpc_task *task) 1695 { 1696 int status = task->tk_status; 1697 1698 /* 1699 * After a call to xprt_reserve(), we must have either 1700 * a request slot or else an error status. 1701 */ 1702 task->tk_status = 0; 1703 if (status >= 0) { 1704 if (task->tk_rqstp) { 1705 task->tk_action = call_refresh; 1706 return; 1707 } 1708 1709 rpc_call_rpcerror(task, -EIO); 1710 return; 1711 } 1712 1713 switch (status) { 1714 case -ENOMEM: 1715 rpc_delay(task, HZ >> 2); 1716 fallthrough; 1717 case -EAGAIN: /* woken up; retry */ 1718 task->tk_action = call_retry_reserve; 1719 return; 1720 default: 1721 rpc_call_rpcerror(task, status); 1722 } 1723 } 1724 1725 /* 1726 * 1c. Retry reserving an RPC call slot 1727 */ 1728 static void 1729 call_retry_reserve(struct rpc_task *task) 1730 { 1731 task->tk_status = 0; 1732 task->tk_action = call_reserveresult; 1733 xprt_retry_reserve(task); 1734 } 1735 1736 /* 1737 * 2. Bind and/or refresh the credentials 1738 */ 1739 static void 1740 call_refresh(struct rpc_task *task) 1741 { 1742 task->tk_action = call_refreshresult; 1743 task->tk_status = 0; 1744 task->tk_client->cl_stats->rpcauthrefresh++; 1745 rpcauth_refreshcred(task); 1746 } 1747 1748 /* 1749 * 2a. Process the results of a credential refresh 1750 */ 1751 static void 1752 call_refreshresult(struct rpc_task *task) 1753 { 1754 int status = task->tk_status; 1755 1756 task->tk_status = 0; 1757 task->tk_action = call_refresh; 1758 switch (status) { 1759 case 0: 1760 if (rpcauth_uptodatecred(task)) { 1761 task->tk_action = call_allocate; 1762 return; 1763 } 1764 /* Use rate-limiting and a max number of retries if refresh 1765 * had status 0 but failed to update the cred. 1766 */ 1767 fallthrough; 1768 case -ETIMEDOUT: 1769 rpc_delay(task, 3*HZ); 1770 fallthrough; 1771 case -EAGAIN: 1772 status = -EACCES; 1773 fallthrough; 1774 case -EKEYEXPIRED: 1775 if (!task->tk_cred_retry) 1776 break; 1777 task->tk_cred_retry--; 1778 trace_rpc_retry_refresh_status(task); 1779 return; 1780 case -ENOMEM: 1781 rpc_delay(task, HZ >> 4); 1782 return; 1783 } 1784 trace_rpc_refresh_status(task); 1785 rpc_call_rpcerror(task, status); 1786 } 1787 1788 /* 1789 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1790 * (Note: buffer memory is freed in xprt_release). 1791 */ 1792 static void 1793 call_allocate(struct rpc_task *task) 1794 { 1795 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth; 1796 struct rpc_rqst *req = task->tk_rqstp; 1797 struct rpc_xprt *xprt = req->rq_xprt; 1798 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1799 int status; 1800 1801 task->tk_status = 0; 1802 task->tk_action = call_encode; 1803 1804 if (req->rq_buffer) 1805 return; 1806 1807 if (proc->p_proc != 0) { 1808 BUG_ON(proc->p_arglen == 0); 1809 if (proc->p_decode != NULL) 1810 BUG_ON(proc->p_replen == 0); 1811 } 1812 1813 /* 1814 * Calculate the size (in quads) of the RPC call 1815 * and reply headers, and convert both values 1816 * to byte sizes. 1817 */ 1818 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + 1819 proc->p_arglen; 1820 req->rq_callsize <<= 2; 1821 /* 1822 * Note: the reply buffer must at minimum allocate enough space 1823 * for the 'struct accepted_reply' from RFC5531. 1824 */ 1825 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ 1826 max_t(size_t, proc->p_replen, 2); 1827 req->rq_rcvsize <<= 2; 1828 1829 status = xprt->ops->buf_alloc(task); 1830 trace_rpc_buf_alloc(task, status); 1831 if (status == 0) 1832 return; 1833 if (status != -ENOMEM) { 1834 rpc_call_rpcerror(task, status); 1835 return; 1836 } 1837 1838 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1839 task->tk_action = call_allocate; 1840 rpc_delay(task, HZ>>4); 1841 return; 1842 } 1843 1844 rpc_call_rpcerror(task, -ERESTARTSYS); 1845 } 1846 1847 static int 1848 rpc_task_need_encode(struct rpc_task *task) 1849 { 1850 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 && 1851 (!(task->tk_flags & RPC_TASK_SENT) || 1852 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) || 1853 xprt_request_need_retransmit(task)); 1854 } 1855 1856 static void 1857 rpc_xdr_encode(struct rpc_task *task) 1858 { 1859 struct rpc_rqst *req = task->tk_rqstp; 1860 struct xdr_stream xdr; 1861 1862 xdr_buf_init(&req->rq_snd_buf, 1863 req->rq_buffer, 1864 req->rq_callsize); 1865 xdr_buf_init(&req->rq_rcv_buf, 1866 req->rq_rbuffer, 1867 req->rq_rcvsize); 1868 1869 req->rq_reply_bytes_recvd = 0; 1870 req->rq_snd_buf.head[0].iov_len = 0; 1871 xdr_init_encode(&xdr, &req->rq_snd_buf, 1872 req->rq_snd_buf.head[0].iov_base, req); 1873 if (rpc_encode_header(task, &xdr)) 1874 return; 1875 1876 task->tk_status = rpcauth_wrap_req(task, &xdr); 1877 } 1878 1879 /* 1880 * 3. Encode arguments of an RPC call 1881 */ 1882 static void 1883 call_encode(struct rpc_task *task) 1884 { 1885 if (!rpc_task_need_encode(task)) 1886 goto out; 1887 1888 /* Dequeue task from the receive queue while we're encoding */ 1889 xprt_request_dequeue_xprt(task); 1890 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1891 rpc_xdr_encode(task); 1892 /* Add task to reply queue before transmission to avoid races */ 1893 if (task->tk_status == 0 && rpc_reply_expected(task)) 1894 task->tk_status = xprt_request_enqueue_receive(task); 1895 /* Did the encode result in an error condition? */ 1896 if (task->tk_status != 0) { 1897 /* Was the error nonfatal? */ 1898 switch (task->tk_status) { 1899 case -EAGAIN: 1900 case -ENOMEM: 1901 rpc_delay(task, HZ >> 4); 1902 break; 1903 case -EKEYEXPIRED: 1904 if (!task->tk_cred_retry) { 1905 rpc_call_rpcerror(task, task->tk_status); 1906 } else { 1907 task->tk_action = call_refresh; 1908 task->tk_cred_retry--; 1909 trace_rpc_retry_refresh_status(task); 1910 } 1911 break; 1912 default: 1913 rpc_call_rpcerror(task, task->tk_status); 1914 } 1915 return; 1916 } 1917 1918 xprt_request_enqueue_transmit(task); 1919 out: 1920 task->tk_action = call_transmit; 1921 /* Check that the connection is OK */ 1922 if (!xprt_bound(task->tk_xprt)) 1923 task->tk_action = call_bind; 1924 else if (!xprt_connected(task->tk_xprt)) 1925 task->tk_action = call_connect; 1926 } 1927 1928 /* 1929 * Helpers to check if the task was already transmitted, and 1930 * to take action when that is the case. 1931 */ 1932 static bool 1933 rpc_task_transmitted(struct rpc_task *task) 1934 { 1935 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1936 } 1937 1938 static void 1939 rpc_task_handle_transmitted(struct rpc_task *task) 1940 { 1941 xprt_end_transmit(task); 1942 task->tk_action = call_transmit_status; 1943 } 1944 1945 /* 1946 * 4. Get the server port number if not yet set 1947 */ 1948 static void 1949 call_bind(struct rpc_task *task) 1950 { 1951 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1952 1953 if (rpc_task_transmitted(task)) { 1954 rpc_task_handle_transmitted(task); 1955 return; 1956 } 1957 1958 if (xprt_bound(xprt)) { 1959 task->tk_action = call_connect; 1960 return; 1961 } 1962 1963 task->tk_action = call_bind_status; 1964 if (!xprt_prepare_transmit(task)) 1965 return; 1966 1967 xprt->ops->rpcbind(task); 1968 } 1969 1970 /* 1971 * 4a. Sort out bind result 1972 */ 1973 static void 1974 call_bind_status(struct rpc_task *task) 1975 { 1976 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1977 int status = -EIO; 1978 1979 if (rpc_task_transmitted(task)) { 1980 rpc_task_handle_transmitted(task); 1981 return; 1982 } 1983 1984 if (task->tk_status >= 0) 1985 goto out_next; 1986 if (xprt_bound(xprt)) { 1987 task->tk_status = 0; 1988 goto out_next; 1989 } 1990 1991 switch (task->tk_status) { 1992 case -ENOMEM: 1993 rpc_delay(task, HZ >> 2); 1994 goto retry_timeout; 1995 case -EACCES: 1996 trace_rpcb_prog_unavail_err(task); 1997 /* fail immediately if this is an RPC ping */ 1998 if (task->tk_msg.rpc_proc->p_proc == 0) { 1999 status = -EOPNOTSUPP; 2000 break; 2001 } 2002 if (task->tk_rebind_retry == 0) 2003 break; 2004 task->tk_rebind_retry--; 2005 rpc_delay(task, 3*HZ); 2006 goto retry_timeout; 2007 case -ENOBUFS: 2008 rpc_delay(task, HZ >> 2); 2009 goto retry_timeout; 2010 case -EAGAIN: 2011 goto retry_timeout; 2012 case -ETIMEDOUT: 2013 trace_rpcb_timeout_err(task); 2014 goto retry_timeout; 2015 case -EPFNOSUPPORT: 2016 /* server doesn't support any rpcbind version we know of */ 2017 trace_rpcb_bind_version_err(task); 2018 break; 2019 case -EPROTONOSUPPORT: 2020 trace_rpcb_bind_version_err(task); 2021 goto retry_timeout; 2022 case -ECONNREFUSED: /* connection problems */ 2023 case -ECONNRESET: 2024 case -ECONNABORTED: 2025 case -ENOTCONN: 2026 case -EHOSTDOWN: 2027 case -ENETDOWN: 2028 case -EHOSTUNREACH: 2029 case -ENETUNREACH: 2030 case -EPIPE: 2031 trace_rpcb_unreachable_err(task); 2032 if (!RPC_IS_SOFTCONN(task)) { 2033 rpc_delay(task, 5*HZ); 2034 goto retry_timeout; 2035 } 2036 status = task->tk_status; 2037 break; 2038 default: 2039 trace_rpcb_unrecognized_err(task); 2040 } 2041 2042 rpc_call_rpcerror(task, status); 2043 return; 2044 out_next: 2045 task->tk_action = call_connect; 2046 return; 2047 retry_timeout: 2048 task->tk_status = 0; 2049 task->tk_action = call_bind; 2050 rpc_check_timeout(task); 2051 } 2052 2053 /* 2054 * 4b. Connect to the RPC server 2055 */ 2056 static void 2057 call_connect(struct rpc_task *task) 2058 { 2059 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2060 2061 if (rpc_task_transmitted(task)) { 2062 rpc_task_handle_transmitted(task); 2063 return; 2064 } 2065 2066 if (xprt_connected(xprt)) { 2067 task->tk_action = call_transmit; 2068 return; 2069 } 2070 2071 task->tk_action = call_connect_status; 2072 if (task->tk_status < 0) 2073 return; 2074 if (task->tk_flags & RPC_TASK_NOCONNECT) { 2075 rpc_call_rpcerror(task, -ENOTCONN); 2076 return; 2077 } 2078 if (!xprt_prepare_transmit(task)) 2079 return; 2080 xprt_connect(task); 2081 } 2082 2083 /* 2084 * 4c. Sort out connect result 2085 */ 2086 static void 2087 call_connect_status(struct rpc_task *task) 2088 { 2089 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2090 struct rpc_clnt *clnt = task->tk_client; 2091 int status = task->tk_status; 2092 2093 if (rpc_task_transmitted(task)) { 2094 rpc_task_handle_transmitted(task); 2095 return; 2096 } 2097 2098 trace_rpc_connect_status(task); 2099 2100 if (task->tk_status == 0) { 2101 clnt->cl_stats->netreconn++; 2102 goto out_next; 2103 } 2104 if (xprt_connected(xprt)) { 2105 task->tk_status = 0; 2106 goto out_next; 2107 } 2108 2109 task->tk_status = 0; 2110 switch (status) { 2111 case -ECONNREFUSED: 2112 /* A positive refusal suggests a rebind is needed. */ 2113 if (RPC_IS_SOFTCONN(task)) 2114 break; 2115 if (clnt->cl_autobind) { 2116 rpc_force_rebind(clnt); 2117 goto out_retry; 2118 } 2119 fallthrough; 2120 case -ECONNRESET: 2121 case -ECONNABORTED: 2122 case -ENETDOWN: 2123 case -ENETUNREACH: 2124 case -EHOSTUNREACH: 2125 case -EPIPE: 2126 case -EPROTO: 2127 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, 2128 task->tk_rqstp->rq_connect_cookie); 2129 if (RPC_IS_SOFTCONN(task)) 2130 break; 2131 /* retry with existing socket, after a delay */ 2132 rpc_delay(task, 3*HZ); 2133 fallthrough; 2134 case -EADDRINUSE: 2135 case -ENOTCONN: 2136 case -EAGAIN: 2137 case -ETIMEDOUT: 2138 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) && 2139 (task->tk_flags & RPC_TASK_MOVEABLE) && 2140 test_bit(XPRT_REMOVE, &xprt->state)) { 2141 struct rpc_xprt *saved = task->tk_xprt; 2142 struct rpc_xprt_switch *xps; 2143 2144 rcu_read_lock(); 2145 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2146 rcu_read_unlock(); 2147 if (xps->xps_nxprts > 1) { 2148 long value; 2149 2150 xprt_release(task); 2151 value = atomic_long_dec_return(&xprt->queuelen); 2152 if (value == 0) 2153 rpc_xprt_switch_remove_xprt(xps, saved, 2154 true); 2155 xprt_put(saved); 2156 task->tk_xprt = NULL; 2157 task->tk_action = call_start; 2158 } 2159 xprt_switch_put(xps); 2160 if (!task->tk_xprt) 2161 return; 2162 } 2163 goto out_retry; 2164 case -ENOBUFS: 2165 rpc_delay(task, HZ >> 2); 2166 goto out_retry; 2167 } 2168 rpc_call_rpcerror(task, status); 2169 return; 2170 out_next: 2171 task->tk_action = call_transmit; 2172 return; 2173 out_retry: 2174 /* Check for timeouts before looping back to call_bind */ 2175 task->tk_action = call_bind; 2176 rpc_check_timeout(task); 2177 } 2178 2179 /* 2180 * 5. Transmit the RPC request, and wait for reply 2181 */ 2182 static void 2183 call_transmit(struct rpc_task *task) 2184 { 2185 if (rpc_task_transmitted(task)) { 2186 rpc_task_handle_transmitted(task); 2187 return; 2188 } 2189 2190 task->tk_action = call_transmit_status; 2191 if (!xprt_prepare_transmit(task)) 2192 return; 2193 task->tk_status = 0; 2194 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2195 if (!xprt_connected(task->tk_xprt)) { 2196 task->tk_status = -ENOTCONN; 2197 return; 2198 } 2199 xprt_transmit(task); 2200 } 2201 xprt_end_transmit(task); 2202 } 2203 2204 /* 2205 * 5a. Handle cleanup after a transmission 2206 */ 2207 static void 2208 call_transmit_status(struct rpc_task *task) 2209 { 2210 task->tk_action = call_status; 2211 2212 /* 2213 * Common case: success. Force the compiler to put this 2214 * test first. 2215 */ 2216 if (rpc_task_transmitted(task)) { 2217 task->tk_status = 0; 2218 xprt_request_wait_receive(task); 2219 return; 2220 } 2221 2222 switch (task->tk_status) { 2223 default: 2224 break; 2225 case -EBADMSG: 2226 task->tk_status = 0; 2227 task->tk_action = call_encode; 2228 break; 2229 /* 2230 * Special cases: if we've been waiting on the 2231 * socket's write_space() callback, or if the 2232 * socket just returned a connection error, 2233 * then hold onto the transport lock. 2234 */ 2235 case -ENOMEM: 2236 case -ENOBUFS: 2237 rpc_delay(task, HZ>>2); 2238 fallthrough; 2239 case -EBADSLT: 2240 case -EAGAIN: 2241 task->tk_action = call_transmit; 2242 task->tk_status = 0; 2243 break; 2244 case -ECONNREFUSED: 2245 case -EHOSTDOWN: 2246 case -ENETDOWN: 2247 case -EHOSTUNREACH: 2248 case -ENETUNREACH: 2249 case -EPERM: 2250 if (RPC_IS_SOFTCONN(task)) { 2251 if (!task->tk_msg.rpc_proc->p_proc) 2252 trace_xprt_ping(task->tk_xprt, 2253 task->tk_status); 2254 rpc_call_rpcerror(task, task->tk_status); 2255 return; 2256 } 2257 fallthrough; 2258 case -ECONNRESET: 2259 case -ECONNABORTED: 2260 case -EADDRINUSE: 2261 case -ENOTCONN: 2262 case -EPIPE: 2263 task->tk_action = call_bind; 2264 task->tk_status = 0; 2265 break; 2266 } 2267 rpc_check_timeout(task); 2268 } 2269 2270 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2271 static void call_bc_transmit(struct rpc_task *task); 2272 static void call_bc_transmit_status(struct rpc_task *task); 2273 2274 static void 2275 call_bc_encode(struct rpc_task *task) 2276 { 2277 xprt_request_enqueue_transmit(task); 2278 task->tk_action = call_bc_transmit; 2279 } 2280 2281 /* 2282 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2283 * addition, disconnect on connectivity errors. 2284 */ 2285 static void 2286 call_bc_transmit(struct rpc_task *task) 2287 { 2288 task->tk_action = call_bc_transmit_status; 2289 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2290 if (!xprt_prepare_transmit(task)) 2291 return; 2292 task->tk_status = 0; 2293 xprt_transmit(task); 2294 } 2295 xprt_end_transmit(task); 2296 } 2297 2298 static void 2299 call_bc_transmit_status(struct rpc_task *task) 2300 { 2301 struct rpc_rqst *req = task->tk_rqstp; 2302 2303 if (rpc_task_transmitted(task)) 2304 task->tk_status = 0; 2305 2306 switch (task->tk_status) { 2307 case 0: 2308 /* Success */ 2309 case -ENETDOWN: 2310 case -EHOSTDOWN: 2311 case -EHOSTUNREACH: 2312 case -ENETUNREACH: 2313 case -ECONNRESET: 2314 case -ECONNREFUSED: 2315 case -EADDRINUSE: 2316 case -ENOTCONN: 2317 case -EPIPE: 2318 break; 2319 case -ENOMEM: 2320 case -ENOBUFS: 2321 rpc_delay(task, HZ>>2); 2322 fallthrough; 2323 case -EBADSLT: 2324 case -EAGAIN: 2325 task->tk_status = 0; 2326 task->tk_action = call_bc_transmit; 2327 return; 2328 case -ETIMEDOUT: 2329 /* 2330 * Problem reaching the server. Disconnect and let the 2331 * forechannel reestablish the connection. The server will 2332 * have to retransmit the backchannel request and we'll 2333 * reprocess it. Since these ops are idempotent, there's no 2334 * need to cache our reply at this time. 2335 */ 2336 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2337 "error: %d\n", task->tk_status); 2338 xprt_conditional_disconnect(req->rq_xprt, 2339 req->rq_connect_cookie); 2340 break; 2341 default: 2342 /* 2343 * We were unable to reply and will have to drop the 2344 * request. The server should reconnect and retransmit. 2345 */ 2346 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2347 "error: %d\n", task->tk_status); 2348 break; 2349 } 2350 task->tk_action = rpc_exit_task; 2351 } 2352 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2353 2354 /* 2355 * 6. Sort out the RPC call status 2356 */ 2357 static void 2358 call_status(struct rpc_task *task) 2359 { 2360 struct rpc_clnt *clnt = task->tk_client; 2361 int status; 2362 2363 if (!task->tk_msg.rpc_proc->p_proc) 2364 trace_xprt_ping(task->tk_xprt, task->tk_status); 2365 2366 status = task->tk_status; 2367 if (status >= 0) { 2368 task->tk_action = call_decode; 2369 return; 2370 } 2371 2372 trace_rpc_call_status(task); 2373 task->tk_status = 0; 2374 switch(status) { 2375 case -EHOSTDOWN: 2376 case -ENETDOWN: 2377 case -EHOSTUNREACH: 2378 case -ENETUNREACH: 2379 case -EPERM: 2380 if (RPC_IS_SOFTCONN(task)) 2381 goto out_exit; 2382 /* 2383 * Delay any retries for 3 seconds, then handle as if it 2384 * were a timeout. 2385 */ 2386 rpc_delay(task, 3*HZ); 2387 fallthrough; 2388 case -ETIMEDOUT: 2389 break; 2390 case -ECONNREFUSED: 2391 case -ECONNRESET: 2392 case -ECONNABORTED: 2393 case -ENOTCONN: 2394 rpc_force_rebind(clnt); 2395 break; 2396 case -EADDRINUSE: 2397 rpc_delay(task, 3*HZ); 2398 fallthrough; 2399 case -EPIPE: 2400 case -EAGAIN: 2401 break; 2402 case -ENFILE: 2403 case -ENOBUFS: 2404 case -ENOMEM: 2405 rpc_delay(task, HZ>>2); 2406 break; 2407 case -EIO: 2408 /* shutdown or soft timeout */ 2409 goto out_exit; 2410 default: 2411 if (clnt->cl_chatty) 2412 printk("%s: RPC call returned error %d\n", 2413 clnt->cl_program->name, -status); 2414 goto out_exit; 2415 } 2416 task->tk_action = call_encode; 2417 if (status != -ECONNRESET && status != -ECONNABORTED) 2418 rpc_check_timeout(task); 2419 return; 2420 out_exit: 2421 rpc_call_rpcerror(task, status); 2422 } 2423 2424 static bool 2425 rpc_check_connected(const struct rpc_rqst *req) 2426 { 2427 /* No allocated request or transport? return true */ 2428 if (!req || !req->rq_xprt) 2429 return true; 2430 return xprt_connected(req->rq_xprt); 2431 } 2432 2433 static void 2434 rpc_check_timeout(struct rpc_task *task) 2435 { 2436 struct rpc_clnt *clnt = task->tk_client; 2437 2438 if (RPC_SIGNALLED(task)) { 2439 rpc_call_rpcerror(task, -ERESTARTSYS); 2440 return; 2441 } 2442 2443 if (xprt_adjust_timeout(task->tk_rqstp) == 0) 2444 return; 2445 2446 trace_rpc_timeout_status(task); 2447 task->tk_timeouts++; 2448 2449 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) { 2450 rpc_call_rpcerror(task, -ETIMEDOUT); 2451 return; 2452 } 2453 2454 if (RPC_IS_SOFT(task)) { 2455 /* 2456 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has 2457 * been sent, it should time out only if the transport 2458 * connection gets terminally broken. 2459 */ 2460 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && 2461 rpc_check_connected(task->tk_rqstp)) 2462 return; 2463 2464 if (clnt->cl_chatty) { 2465 pr_notice_ratelimited( 2466 "%s: server %s not responding, timed out\n", 2467 clnt->cl_program->name, 2468 task->tk_xprt->servername); 2469 } 2470 if (task->tk_flags & RPC_TASK_TIMEOUT) 2471 rpc_call_rpcerror(task, -ETIMEDOUT); 2472 else 2473 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT); 2474 return; 2475 } 2476 2477 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2478 task->tk_flags |= RPC_CALL_MAJORSEEN; 2479 if (clnt->cl_chatty) { 2480 pr_notice_ratelimited( 2481 "%s: server %s not responding, still trying\n", 2482 clnt->cl_program->name, 2483 task->tk_xprt->servername); 2484 } 2485 } 2486 rpc_force_rebind(clnt); 2487 /* 2488 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2489 * event? RFC2203 requires the server to drop all such requests. 2490 */ 2491 rpcauth_invalcred(task); 2492 } 2493 2494 /* 2495 * 7. Decode the RPC reply 2496 */ 2497 static void 2498 call_decode(struct rpc_task *task) 2499 { 2500 struct rpc_clnt *clnt = task->tk_client; 2501 struct rpc_rqst *req = task->tk_rqstp; 2502 struct xdr_stream xdr; 2503 int err; 2504 2505 if (!task->tk_msg.rpc_proc->p_decode) { 2506 task->tk_action = rpc_exit_task; 2507 return; 2508 } 2509 2510 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2511 if (clnt->cl_chatty) { 2512 pr_notice_ratelimited("%s: server %s OK\n", 2513 clnt->cl_program->name, 2514 task->tk_xprt->servername); 2515 } 2516 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2517 } 2518 2519 /* 2520 * Did we ever call xprt_complete_rqst()? If not, we should assume 2521 * the message is incomplete. 2522 */ 2523 err = -EAGAIN; 2524 if (!req->rq_reply_bytes_recvd) 2525 goto out; 2526 2527 /* Ensure that we see all writes made by xprt_complete_rqst() 2528 * before it changed req->rq_reply_bytes_recvd. 2529 */ 2530 smp_rmb(); 2531 2532 req->rq_rcv_buf.len = req->rq_private_buf.len; 2533 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf); 2534 2535 /* Check that the softirq receive buffer is valid */ 2536 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2537 sizeof(req->rq_rcv_buf)) != 0); 2538 2539 xdr_init_decode(&xdr, &req->rq_rcv_buf, 2540 req->rq_rcv_buf.head[0].iov_base, req); 2541 err = rpc_decode_header(task, &xdr); 2542 out: 2543 switch (err) { 2544 case 0: 2545 task->tk_action = rpc_exit_task; 2546 task->tk_status = rpcauth_unwrap_resp(task, &xdr); 2547 return; 2548 case -EAGAIN: 2549 task->tk_status = 0; 2550 if (task->tk_client->cl_discrtry) 2551 xprt_conditional_disconnect(req->rq_xprt, 2552 req->rq_connect_cookie); 2553 task->tk_action = call_encode; 2554 rpc_check_timeout(task); 2555 break; 2556 case -EKEYREJECTED: 2557 task->tk_action = call_reserve; 2558 rpc_check_timeout(task); 2559 rpcauth_invalcred(task); 2560 /* Ensure we obtain a new XID if we retry! */ 2561 xprt_release(task); 2562 } 2563 } 2564 2565 static int 2566 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr) 2567 { 2568 struct rpc_clnt *clnt = task->tk_client; 2569 struct rpc_rqst *req = task->tk_rqstp; 2570 __be32 *p; 2571 int error; 2572 2573 error = -EMSGSIZE; 2574 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2); 2575 if (!p) 2576 goto out_fail; 2577 *p++ = req->rq_xid; 2578 *p++ = rpc_call; 2579 *p++ = cpu_to_be32(RPC_VERSION); 2580 *p++ = cpu_to_be32(clnt->cl_prog); 2581 *p++ = cpu_to_be32(clnt->cl_vers); 2582 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc); 2583 2584 error = rpcauth_marshcred(task, xdr); 2585 if (error < 0) 2586 goto out_fail; 2587 return 0; 2588 out_fail: 2589 trace_rpc_bad_callhdr(task); 2590 rpc_call_rpcerror(task, error); 2591 return error; 2592 } 2593 2594 static noinline int 2595 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) 2596 { 2597 struct rpc_clnt *clnt = task->tk_client; 2598 int error; 2599 __be32 *p; 2600 2601 /* RFC-1014 says that the representation of XDR data must be a 2602 * multiple of four bytes 2603 * - if it isn't pointer subtraction in the NFS client may give 2604 * undefined results 2605 */ 2606 if (task->tk_rqstp->rq_rcv_buf.len & 3) 2607 goto out_unparsable; 2608 2609 p = xdr_inline_decode(xdr, 3 * sizeof(*p)); 2610 if (!p) 2611 goto out_unparsable; 2612 p++; /* skip XID */ 2613 if (*p++ != rpc_reply) 2614 goto out_unparsable; 2615 if (*p++ != rpc_msg_accepted) 2616 goto out_msg_denied; 2617 2618 error = rpcauth_checkverf(task, xdr); 2619 if (error) 2620 goto out_verifier; 2621 2622 p = xdr_inline_decode(xdr, sizeof(*p)); 2623 if (!p) 2624 goto out_unparsable; 2625 switch (*p) { 2626 case rpc_success: 2627 return 0; 2628 case rpc_prog_unavail: 2629 trace_rpc__prog_unavail(task); 2630 error = -EPFNOSUPPORT; 2631 goto out_err; 2632 case rpc_prog_mismatch: 2633 trace_rpc__prog_mismatch(task); 2634 error = -EPROTONOSUPPORT; 2635 goto out_err; 2636 case rpc_proc_unavail: 2637 trace_rpc__proc_unavail(task); 2638 error = -EOPNOTSUPP; 2639 goto out_err; 2640 case rpc_garbage_args: 2641 case rpc_system_err: 2642 trace_rpc__garbage_args(task); 2643 error = -EIO; 2644 break; 2645 default: 2646 goto out_unparsable; 2647 } 2648 2649 out_garbage: 2650 clnt->cl_stats->rpcgarbage++; 2651 if (task->tk_garb_retry) { 2652 task->tk_garb_retry--; 2653 task->tk_action = call_encode; 2654 return -EAGAIN; 2655 } 2656 out_err: 2657 rpc_call_rpcerror(task, error); 2658 return error; 2659 2660 out_unparsable: 2661 trace_rpc__unparsable(task); 2662 error = -EIO; 2663 goto out_garbage; 2664 2665 out_verifier: 2666 trace_rpc_bad_verifier(task); 2667 goto out_err; 2668 2669 out_msg_denied: 2670 error = -EACCES; 2671 p = xdr_inline_decode(xdr, sizeof(*p)); 2672 if (!p) 2673 goto out_unparsable; 2674 switch (*p++) { 2675 case rpc_auth_error: 2676 break; 2677 case rpc_mismatch: 2678 trace_rpc__mismatch(task); 2679 error = -EPROTONOSUPPORT; 2680 goto out_err; 2681 default: 2682 goto out_unparsable; 2683 } 2684 2685 p = xdr_inline_decode(xdr, sizeof(*p)); 2686 if (!p) 2687 goto out_unparsable; 2688 switch (*p++) { 2689 case rpc_autherr_rejectedcred: 2690 case rpc_autherr_rejectedverf: 2691 case rpcsec_gsserr_credproblem: 2692 case rpcsec_gsserr_ctxproblem: 2693 if (!task->tk_cred_retry) 2694 break; 2695 task->tk_cred_retry--; 2696 trace_rpc__stale_creds(task); 2697 return -EKEYREJECTED; 2698 case rpc_autherr_badcred: 2699 case rpc_autherr_badverf: 2700 /* possibly garbled cred/verf? */ 2701 if (!task->tk_garb_retry) 2702 break; 2703 task->tk_garb_retry--; 2704 trace_rpc__bad_creds(task); 2705 task->tk_action = call_encode; 2706 return -EAGAIN; 2707 case rpc_autherr_tooweak: 2708 trace_rpc__auth_tooweak(task); 2709 pr_warn("RPC: server %s requires stronger authentication.\n", 2710 task->tk_xprt->servername); 2711 break; 2712 default: 2713 goto out_unparsable; 2714 } 2715 goto out_err; 2716 } 2717 2718 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2719 const void *obj) 2720 { 2721 } 2722 2723 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2724 void *obj) 2725 { 2726 return 0; 2727 } 2728 2729 static const struct rpc_procinfo rpcproc_null = { 2730 .p_encode = rpcproc_encode_null, 2731 .p_decode = rpcproc_decode_null, 2732 }; 2733 2734 static const struct rpc_procinfo rpcproc_null_noreply = { 2735 .p_encode = rpcproc_encode_null, 2736 }; 2737 2738 static void 2739 rpc_null_call_prepare(struct rpc_task *task, void *data) 2740 { 2741 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT; 2742 rpc_call_start(task); 2743 } 2744 2745 static const struct rpc_call_ops rpc_null_ops = { 2746 .rpc_call_prepare = rpc_null_call_prepare, 2747 .rpc_call_done = rpc_default_callback, 2748 }; 2749 2750 static 2751 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2752 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2753 const struct rpc_call_ops *ops, void *data) 2754 { 2755 struct rpc_message msg = { 2756 .rpc_proc = &rpcproc_null, 2757 }; 2758 struct rpc_task_setup task_setup_data = { 2759 .rpc_client = clnt, 2760 .rpc_xprt = xprt, 2761 .rpc_message = &msg, 2762 .rpc_op_cred = cred, 2763 .callback_ops = ops ?: &rpc_null_ops, 2764 .callback_data = data, 2765 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN | 2766 RPC_TASK_NULLCREDS, 2767 }; 2768 2769 return rpc_run_task(&task_setup_data); 2770 } 2771 2772 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2773 { 2774 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2775 } 2776 EXPORT_SYMBOL_GPL(rpc_call_null); 2777 2778 static int rpc_ping(struct rpc_clnt *clnt) 2779 { 2780 struct rpc_task *task; 2781 int status; 2782 2783 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL); 2784 if (IS_ERR(task)) 2785 return PTR_ERR(task); 2786 status = task->tk_status; 2787 rpc_put_task(task); 2788 return status; 2789 } 2790 2791 static int rpc_ping_noreply(struct rpc_clnt *clnt) 2792 { 2793 struct rpc_message msg = { 2794 .rpc_proc = &rpcproc_null_noreply, 2795 }; 2796 struct rpc_task_setup task_setup_data = { 2797 .rpc_client = clnt, 2798 .rpc_message = &msg, 2799 .callback_ops = &rpc_null_ops, 2800 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS, 2801 }; 2802 struct rpc_task *task; 2803 int status; 2804 2805 task = rpc_run_task(&task_setup_data); 2806 if (IS_ERR(task)) 2807 return PTR_ERR(task); 2808 status = task->tk_status; 2809 rpc_put_task(task); 2810 return status; 2811 } 2812 2813 struct rpc_cb_add_xprt_calldata { 2814 struct rpc_xprt_switch *xps; 2815 struct rpc_xprt *xprt; 2816 }; 2817 2818 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2819 { 2820 struct rpc_cb_add_xprt_calldata *data = calldata; 2821 2822 if (task->tk_status == 0) 2823 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2824 } 2825 2826 static void rpc_cb_add_xprt_release(void *calldata) 2827 { 2828 struct rpc_cb_add_xprt_calldata *data = calldata; 2829 2830 xprt_put(data->xprt); 2831 xprt_switch_put(data->xps); 2832 kfree(data); 2833 } 2834 2835 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2836 .rpc_call_prepare = rpc_null_call_prepare, 2837 .rpc_call_done = rpc_cb_add_xprt_done, 2838 .rpc_release = rpc_cb_add_xprt_release, 2839 }; 2840 2841 /** 2842 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2843 * @clnt: pointer to struct rpc_clnt 2844 * @xps: pointer to struct rpc_xprt_switch, 2845 * @xprt: pointer struct rpc_xprt 2846 * @dummy: unused 2847 */ 2848 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2849 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2850 void *dummy) 2851 { 2852 struct rpc_cb_add_xprt_calldata *data; 2853 struct rpc_task *task; 2854 2855 if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) { 2856 rcu_read_lock(); 2857 pr_warn("SUNRPC: reached max allowed number (%d) did not add " 2858 "transport to server: %s\n", clnt->cl_max_connect, 2859 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 2860 rcu_read_unlock(); 2861 return -EINVAL; 2862 } 2863 2864 data = kmalloc(sizeof(*data), GFP_KERNEL); 2865 if (!data) 2866 return -ENOMEM; 2867 data->xps = xprt_switch_get(xps); 2868 data->xprt = xprt_get(xprt); 2869 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) { 2870 rpc_cb_add_xprt_release(data); 2871 goto success; 2872 } 2873 2874 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC, 2875 &rpc_cb_add_xprt_call_ops, data); 2876 data->xps->xps_nunique_destaddr_xprts++; 2877 rpc_put_task(task); 2878 success: 2879 return 1; 2880 } 2881 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2882 2883 static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt, 2884 struct rpc_xprt *xprt, 2885 struct rpc_add_xprt_test *data) 2886 { 2887 struct rpc_task *task; 2888 int status = -EADDRINUSE; 2889 2890 /* Test the connection */ 2891 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL); 2892 if (IS_ERR(task)) 2893 return PTR_ERR(task); 2894 2895 status = task->tk_status; 2896 rpc_put_task(task); 2897 2898 if (status < 0) 2899 return status; 2900 2901 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ 2902 data->add_xprt_test(clnt, xprt, data->data); 2903 2904 return 0; 2905 } 2906 2907 /** 2908 * rpc_clnt_setup_test_and_add_xprt() 2909 * 2910 * This is an rpc_clnt_add_xprt setup() function which returns 1 so: 2911 * 1) caller of the test function must dereference the rpc_xprt_switch 2912 * and the rpc_xprt. 2913 * 2) test function must call rpc_xprt_switch_add_xprt, usually in 2914 * the rpc_call_done routine. 2915 * 2916 * Upon success (return of 1), the test function adds the new 2917 * transport to the rpc_clnt xprt switch 2918 * 2919 * @clnt: struct rpc_clnt to get the new transport 2920 * @xps: the rpc_xprt_switch to hold the new transport 2921 * @xprt: the rpc_xprt to test 2922 * @data: a struct rpc_add_xprt_test pointer that holds the test function 2923 * and test function call data 2924 */ 2925 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, 2926 struct rpc_xprt_switch *xps, 2927 struct rpc_xprt *xprt, 2928 void *data) 2929 { 2930 int status = -EADDRINUSE; 2931 2932 xprt = xprt_get(xprt); 2933 xprt_switch_get(xps); 2934 2935 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) 2936 goto out_err; 2937 2938 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 2939 if (status < 0) 2940 goto out_err; 2941 2942 status = 1; 2943 out_err: 2944 xprt_put(xprt); 2945 xprt_switch_put(xps); 2946 if (status < 0) 2947 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not " 2948 "added\n", status, 2949 xprt->address_strings[RPC_DISPLAY_ADDR]); 2950 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ 2951 return status; 2952 } 2953 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); 2954 2955 /** 2956 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 2957 * @clnt: pointer to struct rpc_clnt 2958 * @xprtargs: pointer to struct xprt_create 2959 * @setup: callback to test and/or set up the connection 2960 * @data: pointer to setup function data 2961 * 2962 * Creates a new transport using the parameters set in args and 2963 * adds it to clnt. 2964 * If ping is set, then test that connectivity succeeds before 2965 * adding the new transport. 2966 * 2967 */ 2968 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 2969 struct xprt_create *xprtargs, 2970 int (*setup)(struct rpc_clnt *, 2971 struct rpc_xprt_switch *, 2972 struct rpc_xprt *, 2973 void *), 2974 void *data) 2975 { 2976 struct rpc_xprt_switch *xps; 2977 struct rpc_xprt *xprt; 2978 unsigned long connect_timeout; 2979 unsigned long reconnect_timeout; 2980 unsigned char resvport, reuseport; 2981 int ret = 0, ident; 2982 2983 rcu_read_lock(); 2984 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2985 xprt = xprt_iter_xprt(&clnt->cl_xpi); 2986 if (xps == NULL || xprt == NULL) { 2987 rcu_read_unlock(); 2988 xprt_switch_put(xps); 2989 return -EAGAIN; 2990 } 2991 resvport = xprt->resvport; 2992 reuseport = xprt->reuseport; 2993 connect_timeout = xprt->connect_timeout; 2994 reconnect_timeout = xprt->max_reconnect_timeout; 2995 ident = xprt->xprt_class->ident; 2996 rcu_read_unlock(); 2997 2998 if (!xprtargs->ident) 2999 xprtargs->ident = ident; 3000 xprt = xprt_create_transport(xprtargs); 3001 if (IS_ERR(xprt)) { 3002 ret = PTR_ERR(xprt); 3003 goto out_put_switch; 3004 } 3005 xprt->resvport = resvport; 3006 xprt->reuseport = reuseport; 3007 if (xprt->ops->set_connect_timeout != NULL) 3008 xprt->ops->set_connect_timeout(xprt, 3009 connect_timeout, 3010 reconnect_timeout); 3011 3012 rpc_xprt_switch_set_roundrobin(xps); 3013 if (setup) { 3014 ret = setup(clnt, xps, xprt, data); 3015 if (ret != 0) 3016 goto out_put_xprt; 3017 } 3018 rpc_xprt_switch_add_xprt(xps, xprt); 3019 out_put_xprt: 3020 xprt_put(xprt); 3021 out_put_switch: 3022 xprt_switch_put(xps); 3023 return ret; 3024 } 3025 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 3026 3027 static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt, 3028 struct rpc_xprt *xprt, 3029 struct rpc_add_xprt_test *data) 3030 { 3031 struct rpc_xprt_switch *xps; 3032 struct rpc_xprt *main_xprt; 3033 int status = 0; 3034 3035 xprt_get(xprt); 3036 3037 rcu_read_lock(); 3038 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3039 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3040 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3041 (struct sockaddr *)&main_xprt->addr); 3042 rcu_read_unlock(); 3043 xprt_put(main_xprt); 3044 if (status || !test_bit(XPRT_OFFLINE, &xprt->state)) 3045 goto out; 3046 3047 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3048 out: 3049 xprt_put(xprt); 3050 xprt_switch_put(xps); 3051 return status; 3052 } 3053 3054 /* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking 3055 * @clnt rpc_clnt structure 3056 * 3057 * For each offlined transport found in the rpc_clnt structure call 3058 * the function rpc_xprt_probe_trunked() which will determine if this 3059 * transport still belongs to the trunking group. 3060 */ 3061 void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt, 3062 struct rpc_add_xprt_test *data) 3063 { 3064 struct rpc_xprt_iter xpi; 3065 int ret; 3066 3067 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi); 3068 if (ret) 3069 return; 3070 for (;;) { 3071 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 3072 3073 if (!xprt) 3074 break; 3075 ret = rpc_xprt_probe_trunked(clnt, xprt, data); 3076 xprt_put(xprt); 3077 if (ret < 0) 3078 break; 3079 xprt_iter_rewind(&xpi); 3080 } 3081 xprt_iter_destroy(&xpi); 3082 } 3083 EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts); 3084 3085 static int rpc_xprt_offline(struct rpc_clnt *clnt, 3086 struct rpc_xprt *xprt, 3087 void *data) 3088 { 3089 struct rpc_xprt *main_xprt; 3090 struct rpc_xprt_switch *xps; 3091 int err = 0; 3092 3093 xprt_get(xprt); 3094 3095 rcu_read_lock(); 3096 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3097 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3098 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3099 (struct sockaddr *)&main_xprt->addr); 3100 rcu_read_unlock(); 3101 xprt_put(main_xprt); 3102 if (err) 3103 goto out; 3104 3105 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) { 3106 err = -EINTR; 3107 goto out; 3108 } 3109 xprt_set_offline_locked(xprt, xps); 3110 3111 xprt_release_write(xprt, NULL); 3112 out: 3113 xprt_put(xprt); 3114 xprt_switch_put(xps); 3115 return err; 3116 } 3117 3118 /* rpc_clnt_manage_trunked_xprts -- offline trunked transports 3119 * @clnt rpc_clnt structure 3120 * 3121 * For each active transport found in the rpc_clnt structure call 3122 * the function rpc_xprt_offline() which will identify trunked transports 3123 * and will mark them offline. 3124 */ 3125 void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt) 3126 { 3127 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL); 3128 } 3129 EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts); 3130 3131 struct connect_timeout_data { 3132 unsigned long connect_timeout; 3133 unsigned long reconnect_timeout; 3134 }; 3135 3136 static int 3137 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, 3138 struct rpc_xprt *xprt, 3139 void *data) 3140 { 3141 struct connect_timeout_data *timeo = data; 3142 3143 if (xprt->ops->set_connect_timeout) 3144 xprt->ops->set_connect_timeout(xprt, 3145 timeo->connect_timeout, 3146 timeo->reconnect_timeout); 3147 return 0; 3148 } 3149 3150 void 3151 rpc_set_connect_timeout(struct rpc_clnt *clnt, 3152 unsigned long connect_timeout, 3153 unsigned long reconnect_timeout) 3154 { 3155 struct connect_timeout_data timeout = { 3156 .connect_timeout = connect_timeout, 3157 .reconnect_timeout = reconnect_timeout, 3158 }; 3159 rpc_clnt_iterate_for_each_xprt(clnt, 3160 rpc_xprt_set_connect_timeout, 3161 &timeout); 3162 } 3163 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); 3164 3165 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt) 3166 { 3167 rcu_read_lock(); 3168 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3169 rcu_read_unlock(); 3170 } 3171 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put); 3172 3173 void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3174 { 3175 struct rpc_xprt_switch *xps; 3176 3177 rcu_read_lock(); 3178 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3179 rcu_read_unlock(); 3180 xprt_set_online_locked(xprt, xps); 3181 } 3182 3183 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3184 { 3185 if (rpc_clnt_xprt_switch_has_addr(clnt, 3186 (const struct sockaddr *)&xprt->addr)) { 3187 return rpc_clnt_xprt_set_online(clnt, xprt); 3188 } 3189 rcu_read_lock(); 3190 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3191 xprt); 3192 rcu_read_unlock(); 3193 } 3194 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); 3195 3196 void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3197 { 3198 struct rpc_xprt_switch *xps; 3199 3200 rcu_read_lock(); 3201 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3202 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3203 xprt, 0); 3204 xps->xps_nunique_destaddr_xprts--; 3205 rcu_read_unlock(); 3206 } 3207 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt); 3208 3209 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, 3210 const struct sockaddr *sap) 3211 { 3212 struct rpc_xprt_switch *xps; 3213 bool ret; 3214 3215 rcu_read_lock(); 3216 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3217 ret = rpc_xprt_switch_has_addr(xps, sap); 3218 rcu_read_unlock(); 3219 return ret; 3220 } 3221 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); 3222 3223 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3224 static void rpc_show_header(void) 3225 { 3226 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 3227 "-timeout ---ops--\n"); 3228 } 3229 3230 static void rpc_show_task(const struct rpc_clnt *clnt, 3231 const struct rpc_task *task) 3232 { 3233 const char *rpc_waitq = "none"; 3234 3235 if (RPC_IS_QUEUED(task)) 3236 rpc_waitq = rpc_qname(task->tk_waitqueue); 3237 3238 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 3239 task->tk_pid, task->tk_flags, task->tk_status, 3240 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops, 3241 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 3242 task->tk_action, rpc_waitq); 3243 } 3244 3245 void rpc_show_tasks(struct net *net) 3246 { 3247 struct rpc_clnt *clnt; 3248 struct rpc_task *task; 3249 int header = 0; 3250 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 3251 3252 spin_lock(&sn->rpc_client_lock); 3253 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 3254 spin_lock(&clnt->cl_lock); 3255 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 3256 if (!header) { 3257 rpc_show_header(); 3258 header++; 3259 } 3260 rpc_show_task(clnt, task); 3261 } 3262 spin_unlock(&clnt->cl_lock); 3263 } 3264 spin_unlock(&sn->rpc_client_lock); 3265 } 3266 #endif 3267 3268 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 3269 static int 3270 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 3271 struct rpc_xprt *xprt, 3272 void *dummy) 3273 { 3274 return xprt_enable_swap(xprt); 3275 } 3276 3277 int 3278 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 3279 { 3280 while (clnt != clnt->cl_parent) 3281 clnt = clnt->cl_parent; 3282 if (atomic_inc_return(&clnt->cl_swapper) == 1) 3283 return rpc_clnt_iterate_for_each_xprt(clnt, 3284 rpc_clnt_swap_activate_callback, NULL); 3285 return 0; 3286 } 3287 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 3288 3289 static int 3290 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 3291 struct rpc_xprt *xprt, 3292 void *dummy) 3293 { 3294 xprt_disable_swap(xprt); 3295 return 0; 3296 } 3297 3298 void 3299 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 3300 { 3301 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 3302 rpc_clnt_iterate_for_each_xprt(clnt, 3303 rpc_clnt_swap_deactivate_callback, NULL); 3304 } 3305 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 3306 #endif /* CONFIG_SUNRPC_SWAP */ 3307