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 { 791 struct rpc_xprt_switch *xps; 792 793 rcu_read_lock(); 794 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 795 rcu_read_unlock(); 796 if (xps == NULL) 797 return -EAGAIN; 798 xprt_iter_init_listall(xpi, xps); 799 xprt_switch_put(xps); 800 return 0; 801 } 802 803 /** 804 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports 805 * @clnt: pointer to client 806 * @fn: function to apply 807 * @data: void pointer to function data 808 * 809 * Iterates through the list of RPC transports currently attached to the 810 * client and applies the function fn(clnt, xprt, data). 811 * 812 * On error, the iteration stops, and the function returns the error value. 813 */ 814 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 815 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), 816 void *data) 817 { 818 struct rpc_xprt_iter xpi; 819 int ret; 820 821 ret = rpc_clnt_xprt_iter_init(clnt, &xpi); 822 if (ret) 823 return ret; 824 for (;;) { 825 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 826 827 if (!xprt) 828 break; 829 ret = fn(clnt, xprt, data); 830 xprt_put(xprt); 831 if (ret < 0) 832 break; 833 } 834 xprt_iter_destroy(&xpi); 835 return ret; 836 } 837 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); 838 839 /* 840 * Kill all tasks for the given client. 841 * XXX: kill their descendants as well? 842 */ 843 void rpc_killall_tasks(struct rpc_clnt *clnt) 844 { 845 struct rpc_task *rovr; 846 847 848 if (list_empty(&clnt->cl_tasks)) 849 return; 850 851 /* 852 * Spin lock all_tasks to prevent changes... 853 */ 854 trace_rpc_clnt_killall(clnt); 855 spin_lock(&clnt->cl_lock); 856 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) 857 rpc_signal_task(rovr); 858 spin_unlock(&clnt->cl_lock); 859 } 860 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 861 862 /* 863 * Properly shut down an RPC client, terminating all outstanding 864 * requests. 865 */ 866 void rpc_shutdown_client(struct rpc_clnt *clnt) 867 { 868 might_sleep(); 869 870 trace_rpc_clnt_shutdown(clnt); 871 872 while (!list_empty(&clnt->cl_tasks)) { 873 rpc_killall_tasks(clnt); 874 wait_event_timeout(destroy_wait, 875 list_empty(&clnt->cl_tasks), 1*HZ); 876 } 877 878 rpc_release_client(clnt); 879 } 880 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 881 882 /* 883 * Free an RPC client 884 */ 885 static void rpc_free_client_work(struct work_struct *work) 886 { 887 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work); 888 889 trace_rpc_clnt_free(clnt); 890 891 /* These might block on processes that might allocate memory, 892 * so they cannot be called in rpciod, so they are handled separately 893 * here. 894 */ 895 rpc_sysfs_client_destroy(clnt); 896 rpc_clnt_debugfs_unregister(clnt); 897 rpc_free_clid(clnt); 898 rpc_clnt_remove_pipedir(clnt); 899 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 900 901 kfree(clnt); 902 rpciod_down(); 903 } 904 static struct rpc_clnt * 905 rpc_free_client(struct rpc_clnt *clnt) 906 { 907 struct rpc_clnt *parent = NULL; 908 909 trace_rpc_clnt_release(clnt); 910 if (clnt->cl_parent != clnt) 911 parent = clnt->cl_parent; 912 rpc_unregister_client(clnt); 913 rpc_free_iostats(clnt->cl_metrics); 914 clnt->cl_metrics = NULL; 915 xprt_iter_destroy(&clnt->cl_xpi); 916 put_cred(clnt->cl_cred); 917 918 INIT_WORK(&clnt->cl_work, rpc_free_client_work); 919 schedule_work(&clnt->cl_work); 920 return parent; 921 } 922 923 /* 924 * Free an RPC client 925 */ 926 static struct rpc_clnt * 927 rpc_free_auth(struct rpc_clnt *clnt) 928 { 929 /* 930 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 931 * release remaining GSS contexts. This mechanism ensures 932 * that it can do so safely. 933 */ 934 if (clnt->cl_auth != NULL) { 935 rpcauth_release(clnt->cl_auth); 936 clnt->cl_auth = NULL; 937 } 938 if (refcount_dec_and_test(&clnt->cl_count)) 939 return rpc_free_client(clnt); 940 return NULL; 941 } 942 943 /* 944 * Release reference to the RPC client 945 */ 946 void 947 rpc_release_client(struct rpc_clnt *clnt) 948 { 949 do { 950 if (list_empty(&clnt->cl_tasks)) 951 wake_up(&destroy_wait); 952 if (refcount_dec_not_one(&clnt->cl_count)) 953 break; 954 clnt = rpc_free_auth(clnt); 955 } while (clnt != NULL); 956 } 957 EXPORT_SYMBOL_GPL(rpc_release_client); 958 959 /** 960 * rpc_bind_new_program - bind a new RPC program to an existing client 961 * @old: old rpc_client 962 * @program: rpc program to set 963 * @vers: rpc program version 964 * 965 * Clones the rpc client and sets up a new RPC program. This is mainly 966 * of use for enabling different RPC programs to share the same transport. 967 * The Sun NFSv2/v3 ACL protocol can do this. 968 */ 969 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 970 const struct rpc_program *program, 971 u32 vers) 972 { 973 struct rpc_create_args args = { 974 .program = program, 975 .prognumber = program->number, 976 .version = vers, 977 .authflavor = old->cl_auth->au_flavor, 978 .cred = old->cl_cred, 979 }; 980 struct rpc_clnt *clnt; 981 int err; 982 983 clnt = __rpc_clone_client(&args, old); 984 if (IS_ERR(clnt)) 985 goto out; 986 err = rpc_ping(clnt); 987 if (err != 0) { 988 rpc_shutdown_client(clnt); 989 clnt = ERR_PTR(err); 990 } 991 out: 992 return clnt; 993 } 994 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 995 996 struct rpc_xprt * 997 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 998 { 999 struct rpc_xprt_switch *xps; 1000 1001 if (!xprt) 1002 return NULL; 1003 rcu_read_lock(); 1004 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1005 atomic_long_inc(&xps->xps_queuelen); 1006 rcu_read_unlock(); 1007 atomic_long_inc(&xprt->queuelen); 1008 1009 return xprt; 1010 } 1011 1012 static void 1013 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1014 { 1015 struct rpc_xprt_switch *xps; 1016 1017 atomic_long_dec(&xprt->queuelen); 1018 rcu_read_lock(); 1019 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1020 atomic_long_dec(&xps->xps_queuelen); 1021 rcu_read_unlock(); 1022 1023 xprt_put(xprt); 1024 } 1025 1026 void rpc_task_release_transport(struct rpc_task *task) 1027 { 1028 struct rpc_xprt *xprt = task->tk_xprt; 1029 1030 if (xprt) { 1031 task->tk_xprt = NULL; 1032 if (task->tk_client) 1033 rpc_task_release_xprt(task->tk_client, xprt); 1034 else 1035 xprt_put(xprt); 1036 } 1037 } 1038 EXPORT_SYMBOL_GPL(rpc_task_release_transport); 1039 1040 void rpc_task_release_client(struct rpc_task *task) 1041 { 1042 struct rpc_clnt *clnt = task->tk_client; 1043 1044 rpc_task_release_transport(task); 1045 if (clnt != NULL) { 1046 /* Remove from client task list */ 1047 spin_lock(&clnt->cl_lock); 1048 list_del(&task->tk_task); 1049 spin_unlock(&clnt->cl_lock); 1050 task->tk_client = NULL; 1051 1052 rpc_release_client(clnt); 1053 } 1054 } 1055 1056 static struct rpc_xprt * 1057 rpc_task_get_first_xprt(struct rpc_clnt *clnt) 1058 { 1059 struct rpc_xprt *xprt; 1060 1061 rcu_read_lock(); 1062 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 1063 rcu_read_unlock(); 1064 return rpc_task_get_xprt(clnt, xprt); 1065 } 1066 1067 static struct rpc_xprt * 1068 rpc_task_get_next_xprt(struct rpc_clnt *clnt) 1069 { 1070 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi)); 1071 } 1072 1073 static 1074 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) 1075 { 1076 if (task->tk_xprt) { 1077 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) && 1078 (task->tk_flags & RPC_TASK_MOVEABLE))) 1079 return; 1080 xprt_release(task); 1081 xprt_put(task->tk_xprt); 1082 } 1083 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) 1084 task->tk_xprt = rpc_task_get_first_xprt(clnt); 1085 else 1086 task->tk_xprt = rpc_task_get_next_xprt(clnt); 1087 } 1088 1089 static 1090 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 1091 { 1092 rpc_task_set_transport(task, clnt); 1093 task->tk_client = clnt; 1094 refcount_inc(&clnt->cl_count); 1095 if (clnt->cl_softrtry) 1096 task->tk_flags |= RPC_TASK_SOFT; 1097 if (clnt->cl_softerr) 1098 task->tk_flags |= RPC_TASK_TIMEOUT; 1099 if (clnt->cl_noretranstimeo) 1100 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1101 /* Add to the client's list of all tasks */ 1102 spin_lock(&clnt->cl_lock); 1103 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1104 spin_unlock(&clnt->cl_lock); 1105 } 1106 1107 static void 1108 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1109 { 1110 if (msg != NULL) { 1111 task->tk_msg.rpc_proc = msg->rpc_proc; 1112 task->tk_msg.rpc_argp = msg->rpc_argp; 1113 task->tk_msg.rpc_resp = msg->rpc_resp; 1114 task->tk_msg.rpc_cred = msg->rpc_cred; 1115 if (!(task->tk_flags & RPC_TASK_CRED_NOREF)) 1116 get_cred(task->tk_msg.rpc_cred); 1117 } 1118 } 1119 1120 /* 1121 * Default callback for async RPC calls 1122 */ 1123 static void 1124 rpc_default_callback(struct rpc_task *task, void *data) 1125 { 1126 } 1127 1128 static const struct rpc_call_ops rpc_default_ops = { 1129 .rpc_call_done = rpc_default_callback, 1130 }; 1131 1132 /** 1133 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1134 * @task_setup_data: pointer to task initialisation data 1135 */ 1136 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1137 { 1138 struct rpc_task *task; 1139 1140 task = rpc_new_task(task_setup_data); 1141 if (IS_ERR(task)) 1142 return task; 1143 1144 if (!RPC_IS_ASYNC(task)) 1145 task->tk_flags |= RPC_TASK_CRED_NOREF; 1146 1147 rpc_task_set_client(task, task_setup_data->rpc_client); 1148 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1149 1150 if (task->tk_action == NULL) 1151 rpc_call_start(task); 1152 1153 atomic_inc(&task->tk_count); 1154 rpc_execute(task); 1155 return task; 1156 } 1157 EXPORT_SYMBOL_GPL(rpc_run_task); 1158 1159 /** 1160 * rpc_call_sync - Perform a synchronous RPC call 1161 * @clnt: pointer to RPC client 1162 * @msg: RPC call parameters 1163 * @flags: RPC call flags 1164 */ 1165 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1166 { 1167 struct rpc_task *task; 1168 struct rpc_task_setup task_setup_data = { 1169 .rpc_client = clnt, 1170 .rpc_message = msg, 1171 .callback_ops = &rpc_default_ops, 1172 .flags = flags, 1173 }; 1174 int status; 1175 1176 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1177 if (flags & RPC_TASK_ASYNC) { 1178 rpc_release_calldata(task_setup_data.callback_ops, 1179 task_setup_data.callback_data); 1180 return -EINVAL; 1181 } 1182 1183 task = rpc_run_task(&task_setup_data); 1184 if (IS_ERR(task)) 1185 return PTR_ERR(task); 1186 status = task->tk_status; 1187 rpc_put_task(task); 1188 return status; 1189 } 1190 EXPORT_SYMBOL_GPL(rpc_call_sync); 1191 1192 /** 1193 * rpc_call_async - Perform an asynchronous RPC call 1194 * @clnt: pointer to RPC client 1195 * @msg: RPC call parameters 1196 * @flags: RPC call flags 1197 * @tk_ops: RPC call ops 1198 * @data: user call data 1199 */ 1200 int 1201 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1202 const struct rpc_call_ops *tk_ops, void *data) 1203 { 1204 struct rpc_task *task; 1205 struct rpc_task_setup task_setup_data = { 1206 .rpc_client = clnt, 1207 .rpc_message = msg, 1208 .callback_ops = tk_ops, 1209 .callback_data = data, 1210 .flags = flags|RPC_TASK_ASYNC, 1211 }; 1212 1213 task = rpc_run_task(&task_setup_data); 1214 if (IS_ERR(task)) 1215 return PTR_ERR(task); 1216 rpc_put_task(task); 1217 return 0; 1218 } 1219 EXPORT_SYMBOL_GPL(rpc_call_async); 1220 1221 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1222 static void call_bc_encode(struct rpc_task *task); 1223 1224 /** 1225 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1226 * rpc_execute against it 1227 * @req: RPC request 1228 */ 1229 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) 1230 { 1231 struct rpc_task *task; 1232 struct rpc_task_setup task_setup_data = { 1233 .callback_ops = &rpc_default_ops, 1234 .flags = RPC_TASK_SOFTCONN | 1235 RPC_TASK_NO_RETRANS_TIMEOUT, 1236 }; 1237 1238 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1239 /* 1240 * Create an rpc_task to send the data 1241 */ 1242 task = rpc_new_task(&task_setup_data); 1243 if (IS_ERR(task)) { 1244 xprt_free_bc_request(req); 1245 return task; 1246 } 1247 1248 xprt_init_bc_request(req, task); 1249 1250 task->tk_action = call_bc_encode; 1251 atomic_inc(&task->tk_count); 1252 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1253 rpc_execute(task); 1254 1255 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1256 return task; 1257 } 1258 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1259 1260 /** 1261 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages 1262 * @req: RPC request to prepare 1263 * @pages: vector of struct page pointers 1264 * @base: offset in first page where receive should start, in bytes 1265 * @len: expected size of the upper layer data payload, in bytes 1266 * @hdrsize: expected size of upper layer reply header, in XDR words 1267 * 1268 */ 1269 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, 1270 unsigned int base, unsigned int len, 1271 unsigned int hdrsize) 1272 { 1273 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; 1274 1275 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); 1276 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); 1277 } 1278 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages); 1279 1280 void 1281 rpc_call_start(struct rpc_task *task) 1282 { 1283 task->tk_action = call_start; 1284 } 1285 EXPORT_SYMBOL_GPL(rpc_call_start); 1286 1287 /** 1288 * rpc_peeraddr - extract remote peer address from clnt's xprt 1289 * @clnt: RPC client structure 1290 * @buf: target buffer 1291 * @bufsize: length of target buffer 1292 * 1293 * Returns the number of bytes that are actually in the stored address. 1294 */ 1295 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1296 { 1297 size_t bytes; 1298 struct rpc_xprt *xprt; 1299 1300 rcu_read_lock(); 1301 xprt = rcu_dereference(clnt->cl_xprt); 1302 1303 bytes = xprt->addrlen; 1304 if (bytes > bufsize) 1305 bytes = bufsize; 1306 memcpy(buf, &xprt->addr, bytes); 1307 rcu_read_unlock(); 1308 1309 return bytes; 1310 } 1311 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1312 1313 /** 1314 * rpc_peeraddr2str - return remote peer address in printable format 1315 * @clnt: RPC client structure 1316 * @format: address format 1317 * 1318 * NB: the lifetime of the memory referenced by the returned pointer is 1319 * the same as the rpc_xprt itself. As long as the caller uses this 1320 * pointer, it must hold the RCU read lock. 1321 */ 1322 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1323 enum rpc_display_format_t format) 1324 { 1325 struct rpc_xprt *xprt; 1326 1327 xprt = rcu_dereference(clnt->cl_xprt); 1328 1329 if (xprt->address_strings[format] != NULL) 1330 return xprt->address_strings[format]; 1331 else 1332 return "unprintable"; 1333 } 1334 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1335 1336 static const struct sockaddr_in rpc_inaddr_loopback = { 1337 .sin_family = AF_INET, 1338 .sin_addr.s_addr = htonl(INADDR_ANY), 1339 }; 1340 1341 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1342 .sin6_family = AF_INET6, 1343 .sin6_addr = IN6ADDR_ANY_INIT, 1344 }; 1345 1346 /* 1347 * Try a getsockname() on a connected datagram socket. Using a 1348 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1349 * This conserves the ephemeral port number space. 1350 * 1351 * Returns zero and fills in "buf" if successful; otherwise, a 1352 * negative errno is returned. 1353 */ 1354 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1355 struct sockaddr *buf) 1356 { 1357 struct socket *sock; 1358 int err; 1359 1360 err = __sock_create(net, sap->sa_family, 1361 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1362 if (err < 0) { 1363 dprintk("RPC: can't create UDP socket (%d)\n", err); 1364 goto out; 1365 } 1366 1367 switch (sap->sa_family) { 1368 case AF_INET: 1369 err = kernel_bind(sock, 1370 (struct sockaddr *)&rpc_inaddr_loopback, 1371 sizeof(rpc_inaddr_loopback)); 1372 break; 1373 case AF_INET6: 1374 err = kernel_bind(sock, 1375 (struct sockaddr *)&rpc_in6addr_loopback, 1376 sizeof(rpc_in6addr_loopback)); 1377 break; 1378 default: 1379 err = -EAFNOSUPPORT; 1380 goto out; 1381 } 1382 if (err < 0) { 1383 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1384 goto out_release; 1385 } 1386 1387 err = kernel_connect(sock, sap, salen, 0); 1388 if (err < 0) { 1389 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1390 goto out_release; 1391 } 1392 1393 err = kernel_getsockname(sock, buf); 1394 if (err < 0) { 1395 dprintk("RPC: getsockname failed (%d)\n", err); 1396 goto out_release; 1397 } 1398 1399 err = 0; 1400 if (buf->sa_family == AF_INET6) { 1401 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1402 sin6->sin6_scope_id = 0; 1403 } 1404 dprintk("RPC: %s succeeded\n", __func__); 1405 1406 out_release: 1407 sock_release(sock); 1408 out: 1409 return err; 1410 } 1411 1412 /* 1413 * Scraping a connected socket failed, so we don't have a useable 1414 * local address. Fallback: generate an address that will prevent 1415 * the server from calling us back. 1416 * 1417 * Returns zero and fills in "buf" if successful; otherwise, a 1418 * negative errno is returned. 1419 */ 1420 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1421 { 1422 switch (family) { 1423 case AF_INET: 1424 if (buflen < sizeof(rpc_inaddr_loopback)) 1425 return -EINVAL; 1426 memcpy(buf, &rpc_inaddr_loopback, 1427 sizeof(rpc_inaddr_loopback)); 1428 break; 1429 case AF_INET6: 1430 if (buflen < sizeof(rpc_in6addr_loopback)) 1431 return -EINVAL; 1432 memcpy(buf, &rpc_in6addr_loopback, 1433 sizeof(rpc_in6addr_loopback)); 1434 break; 1435 default: 1436 dprintk("RPC: %s: address family not supported\n", 1437 __func__); 1438 return -EAFNOSUPPORT; 1439 } 1440 dprintk("RPC: %s: succeeded\n", __func__); 1441 return 0; 1442 } 1443 1444 /** 1445 * rpc_localaddr - discover local endpoint address for an RPC client 1446 * @clnt: RPC client structure 1447 * @buf: target buffer 1448 * @buflen: size of target buffer, in bytes 1449 * 1450 * Returns zero and fills in "buf" and "buflen" if successful; 1451 * otherwise, a negative errno is returned. 1452 * 1453 * This works even if the underlying transport is not currently connected, 1454 * or if the upper layer never previously provided a source address. 1455 * 1456 * The result of this function call is transient: multiple calls in 1457 * succession may give different results, depending on how local 1458 * networking configuration changes over time. 1459 */ 1460 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1461 { 1462 struct sockaddr_storage address; 1463 struct sockaddr *sap = (struct sockaddr *)&address; 1464 struct rpc_xprt *xprt; 1465 struct net *net; 1466 size_t salen; 1467 int err; 1468 1469 rcu_read_lock(); 1470 xprt = rcu_dereference(clnt->cl_xprt); 1471 salen = xprt->addrlen; 1472 memcpy(sap, &xprt->addr, salen); 1473 net = get_net(xprt->xprt_net); 1474 rcu_read_unlock(); 1475 1476 rpc_set_port(sap, 0); 1477 err = rpc_sockname(net, sap, salen, buf); 1478 put_net(net); 1479 if (err != 0) 1480 /* Couldn't discover local address, return ANYADDR */ 1481 return rpc_anyaddr(sap->sa_family, buf, buflen); 1482 return 0; 1483 } 1484 EXPORT_SYMBOL_GPL(rpc_localaddr); 1485 1486 void 1487 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1488 { 1489 struct rpc_xprt *xprt; 1490 1491 rcu_read_lock(); 1492 xprt = rcu_dereference(clnt->cl_xprt); 1493 if (xprt->ops->set_buffer_size) 1494 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1495 rcu_read_unlock(); 1496 } 1497 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1498 1499 /** 1500 * rpc_net_ns - Get the network namespace for this RPC client 1501 * @clnt: RPC client to query 1502 * 1503 */ 1504 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1505 { 1506 struct net *ret; 1507 1508 rcu_read_lock(); 1509 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1510 rcu_read_unlock(); 1511 return ret; 1512 } 1513 EXPORT_SYMBOL_GPL(rpc_net_ns); 1514 1515 /** 1516 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1517 * @clnt: RPC client to query 1518 * 1519 * For stream transports, this is one RPC record fragment (see RFC 1520 * 1831), as we don't support multi-record requests yet. For datagram 1521 * transports, this is the size of an IP packet minus the IP, UDP, and 1522 * RPC header sizes. 1523 */ 1524 size_t rpc_max_payload(struct rpc_clnt *clnt) 1525 { 1526 size_t ret; 1527 1528 rcu_read_lock(); 1529 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1530 rcu_read_unlock(); 1531 return ret; 1532 } 1533 EXPORT_SYMBOL_GPL(rpc_max_payload); 1534 1535 /** 1536 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1537 * @clnt: RPC client to query 1538 */ 1539 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1540 { 1541 struct rpc_xprt *xprt; 1542 size_t ret; 1543 1544 rcu_read_lock(); 1545 xprt = rcu_dereference(clnt->cl_xprt); 1546 ret = xprt->ops->bc_maxpayload(xprt); 1547 rcu_read_unlock(); 1548 return ret; 1549 } 1550 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1551 1552 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt) 1553 { 1554 struct rpc_xprt *xprt; 1555 unsigned int ret; 1556 1557 rcu_read_lock(); 1558 xprt = rcu_dereference(clnt->cl_xprt); 1559 ret = xprt->ops->bc_num_slots(xprt); 1560 rcu_read_unlock(); 1561 return ret; 1562 } 1563 EXPORT_SYMBOL_GPL(rpc_num_bc_slots); 1564 1565 /** 1566 * rpc_force_rebind - force transport to check that remote port is unchanged 1567 * @clnt: client to rebind 1568 * 1569 */ 1570 void rpc_force_rebind(struct rpc_clnt *clnt) 1571 { 1572 if (clnt->cl_autobind) { 1573 rcu_read_lock(); 1574 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1575 rcu_read_unlock(); 1576 } 1577 } 1578 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1579 1580 static int 1581 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *)) 1582 { 1583 task->tk_status = 0; 1584 task->tk_rpc_status = 0; 1585 task->tk_action = action; 1586 return 1; 1587 } 1588 1589 /* 1590 * Restart an (async) RPC call. Usually called from within the 1591 * exit handler. 1592 */ 1593 int 1594 rpc_restart_call(struct rpc_task *task) 1595 { 1596 return __rpc_restart_call(task, call_start); 1597 } 1598 EXPORT_SYMBOL_GPL(rpc_restart_call); 1599 1600 /* 1601 * Restart an (async) RPC call from the call_prepare state. 1602 * Usually called from within the exit handler. 1603 */ 1604 int 1605 rpc_restart_call_prepare(struct rpc_task *task) 1606 { 1607 if (task->tk_ops->rpc_call_prepare != NULL) 1608 return __rpc_restart_call(task, rpc_prepare_task); 1609 return rpc_restart_call(task); 1610 } 1611 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1612 1613 const char 1614 *rpc_proc_name(const struct rpc_task *task) 1615 { 1616 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1617 1618 if (proc) { 1619 if (proc->p_name) 1620 return proc->p_name; 1621 else 1622 return "NULL"; 1623 } else 1624 return "no proc"; 1625 } 1626 1627 static void 1628 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status) 1629 { 1630 trace_rpc_call_rpcerror(task, tk_status, rpc_status); 1631 task->tk_rpc_status = rpc_status; 1632 rpc_exit(task, tk_status); 1633 } 1634 1635 static void 1636 rpc_call_rpcerror(struct rpc_task *task, int status) 1637 { 1638 __rpc_call_rpcerror(task, status, status); 1639 } 1640 1641 /* 1642 * 0. Initial state 1643 * 1644 * Other FSM states can be visited zero or more times, but 1645 * this state is visited exactly once for each RPC. 1646 */ 1647 static void 1648 call_start(struct rpc_task *task) 1649 { 1650 struct rpc_clnt *clnt = task->tk_client; 1651 int idx = task->tk_msg.rpc_proc->p_statidx; 1652 1653 trace_rpc_request(task); 1654 1655 /* Increment call count (version might not be valid for ping) */ 1656 if (clnt->cl_program->version[clnt->cl_vers]) 1657 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; 1658 clnt->cl_stats->rpccnt++; 1659 task->tk_action = call_reserve; 1660 rpc_task_set_transport(task, clnt); 1661 } 1662 1663 /* 1664 * 1. Reserve an RPC call slot 1665 */ 1666 static void 1667 call_reserve(struct rpc_task *task) 1668 { 1669 task->tk_status = 0; 1670 task->tk_action = call_reserveresult; 1671 xprt_reserve(task); 1672 } 1673 1674 static void call_retry_reserve(struct rpc_task *task); 1675 1676 /* 1677 * 1b. Grok the result of xprt_reserve() 1678 */ 1679 static void 1680 call_reserveresult(struct rpc_task *task) 1681 { 1682 int status = task->tk_status; 1683 1684 /* 1685 * After a call to xprt_reserve(), we must have either 1686 * a request slot or else an error status. 1687 */ 1688 task->tk_status = 0; 1689 if (status >= 0) { 1690 if (task->tk_rqstp) { 1691 task->tk_action = call_refresh; 1692 return; 1693 } 1694 1695 rpc_call_rpcerror(task, -EIO); 1696 return; 1697 } 1698 1699 switch (status) { 1700 case -ENOMEM: 1701 rpc_delay(task, HZ >> 2); 1702 fallthrough; 1703 case -EAGAIN: /* woken up; retry */ 1704 task->tk_action = call_retry_reserve; 1705 return; 1706 default: 1707 rpc_call_rpcerror(task, status); 1708 } 1709 } 1710 1711 /* 1712 * 1c. Retry reserving an RPC call slot 1713 */ 1714 static void 1715 call_retry_reserve(struct rpc_task *task) 1716 { 1717 task->tk_status = 0; 1718 task->tk_action = call_reserveresult; 1719 xprt_retry_reserve(task); 1720 } 1721 1722 /* 1723 * 2. Bind and/or refresh the credentials 1724 */ 1725 static void 1726 call_refresh(struct rpc_task *task) 1727 { 1728 task->tk_action = call_refreshresult; 1729 task->tk_status = 0; 1730 task->tk_client->cl_stats->rpcauthrefresh++; 1731 rpcauth_refreshcred(task); 1732 } 1733 1734 /* 1735 * 2a. Process the results of a credential refresh 1736 */ 1737 static void 1738 call_refreshresult(struct rpc_task *task) 1739 { 1740 int status = task->tk_status; 1741 1742 task->tk_status = 0; 1743 task->tk_action = call_refresh; 1744 switch (status) { 1745 case 0: 1746 if (rpcauth_uptodatecred(task)) { 1747 task->tk_action = call_allocate; 1748 return; 1749 } 1750 /* Use rate-limiting and a max number of retries if refresh 1751 * had status 0 but failed to update the cred. 1752 */ 1753 fallthrough; 1754 case -ETIMEDOUT: 1755 rpc_delay(task, 3*HZ); 1756 fallthrough; 1757 case -EAGAIN: 1758 status = -EACCES; 1759 fallthrough; 1760 case -EKEYEXPIRED: 1761 if (!task->tk_cred_retry) 1762 break; 1763 task->tk_cred_retry--; 1764 trace_rpc_retry_refresh_status(task); 1765 return; 1766 case -ENOMEM: 1767 rpc_delay(task, HZ >> 4); 1768 return; 1769 } 1770 trace_rpc_refresh_status(task); 1771 rpc_call_rpcerror(task, status); 1772 } 1773 1774 /* 1775 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1776 * (Note: buffer memory is freed in xprt_release). 1777 */ 1778 static void 1779 call_allocate(struct rpc_task *task) 1780 { 1781 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth; 1782 struct rpc_rqst *req = task->tk_rqstp; 1783 struct rpc_xprt *xprt = req->rq_xprt; 1784 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1785 int status; 1786 1787 task->tk_status = 0; 1788 task->tk_action = call_encode; 1789 1790 if (req->rq_buffer) 1791 return; 1792 1793 if (proc->p_proc != 0) { 1794 BUG_ON(proc->p_arglen == 0); 1795 if (proc->p_decode != NULL) 1796 BUG_ON(proc->p_replen == 0); 1797 } 1798 1799 /* 1800 * Calculate the size (in quads) of the RPC call 1801 * and reply headers, and convert both values 1802 * to byte sizes. 1803 */ 1804 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + 1805 proc->p_arglen; 1806 req->rq_callsize <<= 2; 1807 /* 1808 * Note: the reply buffer must at minimum allocate enough space 1809 * for the 'struct accepted_reply' from RFC5531. 1810 */ 1811 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ 1812 max_t(size_t, proc->p_replen, 2); 1813 req->rq_rcvsize <<= 2; 1814 1815 status = xprt->ops->buf_alloc(task); 1816 trace_rpc_buf_alloc(task, status); 1817 if (status == 0) 1818 return; 1819 if (status != -ENOMEM) { 1820 rpc_call_rpcerror(task, status); 1821 return; 1822 } 1823 1824 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1825 task->tk_action = call_allocate; 1826 rpc_delay(task, HZ>>4); 1827 return; 1828 } 1829 1830 rpc_call_rpcerror(task, -ERESTARTSYS); 1831 } 1832 1833 static int 1834 rpc_task_need_encode(struct rpc_task *task) 1835 { 1836 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 && 1837 (!(task->tk_flags & RPC_TASK_SENT) || 1838 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) || 1839 xprt_request_need_retransmit(task)); 1840 } 1841 1842 static void 1843 rpc_xdr_encode(struct rpc_task *task) 1844 { 1845 struct rpc_rqst *req = task->tk_rqstp; 1846 struct xdr_stream xdr; 1847 1848 xdr_buf_init(&req->rq_snd_buf, 1849 req->rq_buffer, 1850 req->rq_callsize); 1851 xdr_buf_init(&req->rq_rcv_buf, 1852 req->rq_rbuffer, 1853 req->rq_rcvsize); 1854 1855 req->rq_reply_bytes_recvd = 0; 1856 req->rq_snd_buf.head[0].iov_len = 0; 1857 xdr_init_encode(&xdr, &req->rq_snd_buf, 1858 req->rq_snd_buf.head[0].iov_base, req); 1859 xdr_free_bvec(&req->rq_snd_buf); 1860 if (rpc_encode_header(task, &xdr)) 1861 return; 1862 1863 task->tk_status = rpcauth_wrap_req(task, &xdr); 1864 } 1865 1866 /* 1867 * 3. Encode arguments of an RPC call 1868 */ 1869 static void 1870 call_encode(struct rpc_task *task) 1871 { 1872 if (!rpc_task_need_encode(task)) 1873 goto out; 1874 1875 /* Dequeue task from the receive queue while we're encoding */ 1876 xprt_request_dequeue_xprt(task); 1877 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1878 rpc_xdr_encode(task); 1879 /* Add task to reply queue before transmission to avoid races */ 1880 if (task->tk_status == 0 && rpc_reply_expected(task)) 1881 task->tk_status = xprt_request_enqueue_receive(task); 1882 /* Did the encode result in an error condition? */ 1883 if (task->tk_status != 0) { 1884 /* Was the error nonfatal? */ 1885 switch (task->tk_status) { 1886 case -EAGAIN: 1887 case -ENOMEM: 1888 rpc_delay(task, HZ >> 4); 1889 break; 1890 case -EKEYEXPIRED: 1891 if (!task->tk_cred_retry) { 1892 rpc_exit(task, task->tk_status); 1893 } else { 1894 task->tk_action = call_refresh; 1895 task->tk_cred_retry--; 1896 trace_rpc_retry_refresh_status(task); 1897 } 1898 break; 1899 default: 1900 rpc_call_rpcerror(task, task->tk_status); 1901 } 1902 return; 1903 } 1904 1905 xprt_request_enqueue_transmit(task); 1906 out: 1907 task->tk_action = call_transmit; 1908 /* Check that the connection is OK */ 1909 if (!xprt_bound(task->tk_xprt)) 1910 task->tk_action = call_bind; 1911 else if (!xprt_connected(task->tk_xprt)) 1912 task->tk_action = call_connect; 1913 } 1914 1915 /* 1916 * Helpers to check if the task was already transmitted, and 1917 * to take action when that is the case. 1918 */ 1919 static bool 1920 rpc_task_transmitted(struct rpc_task *task) 1921 { 1922 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 1923 } 1924 1925 static void 1926 rpc_task_handle_transmitted(struct rpc_task *task) 1927 { 1928 xprt_end_transmit(task); 1929 task->tk_action = call_transmit_status; 1930 } 1931 1932 /* 1933 * 4. Get the server port number if not yet set 1934 */ 1935 static void 1936 call_bind(struct rpc_task *task) 1937 { 1938 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1939 1940 if (rpc_task_transmitted(task)) { 1941 rpc_task_handle_transmitted(task); 1942 return; 1943 } 1944 1945 if (xprt_bound(xprt)) { 1946 task->tk_action = call_connect; 1947 return; 1948 } 1949 1950 task->tk_action = call_bind_status; 1951 if (!xprt_prepare_transmit(task)) 1952 return; 1953 1954 xprt->ops->rpcbind(task); 1955 } 1956 1957 /* 1958 * 4a. Sort out bind result 1959 */ 1960 static void 1961 call_bind_status(struct rpc_task *task) 1962 { 1963 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1964 int status = -EIO; 1965 1966 if (rpc_task_transmitted(task)) { 1967 rpc_task_handle_transmitted(task); 1968 return; 1969 } 1970 1971 if (task->tk_status >= 0) 1972 goto out_next; 1973 if (xprt_bound(xprt)) { 1974 task->tk_status = 0; 1975 goto out_next; 1976 } 1977 1978 switch (task->tk_status) { 1979 case -ENOMEM: 1980 rpc_delay(task, HZ >> 2); 1981 goto retry_timeout; 1982 case -EACCES: 1983 trace_rpcb_prog_unavail_err(task); 1984 /* fail immediately if this is an RPC ping */ 1985 if (task->tk_msg.rpc_proc->p_proc == 0) { 1986 status = -EOPNOTSUPP; 1987 break; 1988 } 1989 if (task->tk_rebind_retry == 0) 1990 break; 1991 task->tk_rebind_retry--; 1992 rpc_delay(task, 3*HZ); 1993 goto retry_timeout; 1994 case -ENOBUFS: 1995 rpc_delay(task, HZ >> 2); 1996 goto retry_timeout; 1997 case -EAGAIN: 1998 goto retry_timeout; 1999 case -ETIMEDOUT: 2000 trace_rpcb_timeout_err(task); 2001 goto retry_timeout; 2002 case -EPFNOSUPPORT: 2003 /* server doesn't support any rpcbind version we know of */ 2004 trace_rpcb_bind_version_err(task); 2005 break; 2006 case -EPROTONOSUPPORT: 2007 trace_rpcb_bind_version_err(task); 2008 goto retry_timeout; 2009 case -ECONNREFUSED: /* connection problems */ 2010 case -ECONNRESET: 2011 case -ECONNABORTED: 2012 case -ENOTCONN: 2013 case -EHOSTDOWN: 2014 case -ENETDOWN: 2015 case -EHOSTUNREACH: 2016 case -ENETUNREACH: 2017 case -EPIPE: 2018 trace_rpcb_unreachable_err(task); 2019 if (!RPC_IS_SOFTCONN(task)) { 2020 rpc_delay(task, 5*HZ); 2021 goto retry_timeout; 2022 } 2023 status = task->tk_status; 2024 break; 2025 default: 2026 trace_rpcb_unrecognized_err(task); 2027 } 2028 2029 rpc_call_rpcerror(task, status); 2030 return; 2031 out_next: 2032 task->tk_action = call_connect; 2033 return; 2034 retry_timeout: 2035 task->tk_status = 0; 2036 task->tk_action = call_bind; 2037 rpc_check_timeout(task); 2038 } 2039 2040 /* 2041 * 4b. Connect to the RPC server 2042 */ 2043 static void 2044 call_connect(struct rpc_task *task) 2045 { 2046 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2047 2048 if (rpc_task_transmitted(task)) { 2049 rpc_task_handle_transmitted(task); 2050 return; 2051 } 2052 2053 if (xprt_connected(xprt)) { 2054 task->tk_action = call_transmit; 2055 return; 2056 } 2057 2058 task->tk_action = call_connect_status; 2059 if (task->tk_status < 0) 2060 return; 2061 if (task->tk_flags & RPC_TASK_NOCONNECT) { 2062 rpc_call_rpcerror(task, -ENOTCONN); 2063 return; 2064 } 2065 if (!xprt_prepare_transmit(task)) 2066 return; 2067 xprt_connect(task); 2068 } 2069 2070 /* 2071 * 4c. Sort out connect result 2072 */ 2073 static void 2074 call_connect_status(struct rpc_task *task) 2075 { 2076 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2077 struct rpc_clnt *clnt = task->tk_client; 2078 int status = task->tk_status; 2079 2080 if (rpc_task_transmitted(task)) { 2081 rpc_task_handle_transmitted(task); 2082 return; 2083 } 2084 2085 trace_rpc_connect_status(task); 2086 2087 if (task->tk_status == 0) { 2088 clnt->cl_stats->netreconn++; 2089 goto out_next; 2090 } 2091 if (xprt_connected(xprt)) { 2092 task->tk_status = 0; 2093 goto out_next; 2094 } 2095 2096 task->tk_status = 0; 2097 switch (status) { 2098 case -ECONNREFUSED: 2099 /* A positive refusal suggests a rebind is needed. */ 2100 if (RPC_IS_SOFTCONN(task)) 2101 break; 2102 if (clnt->cl_autobind) { 2103 rpc_force_rebind(clnt); 2104 goto out_retry; 2105 } 2106 fallthrough; 2107 case -ECONNRESET: 2108 case -ECONNABORTED: 2109 case -ENETDOWN: 2110 case -ENETUNREACH: 2111 case -EHOSTUNREACH: 2112 case -EPIPE: 2113 case -EPROTO: 2114 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, 2115 task->tk_rqstp->rq_connect_cookie); 2116 if (RPC_IS_SOFTCONN(task)) 2117 break; 2118 /* retry with existing socket, after a delay */ 2119 rpc_delay(task, 3*HZ); 2120 fallthrough; 2121 case -EADDRINUSE: 2122 case -ENOTCONN: 2123 case -EAGAIN: 2124 case -ETIMEDOUT: 2125 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) && 2126 (task->tk_flags & RPC_TASK_MOVEABLE) && 2127 test_bit(XPRT_REMOVE, &xprt->state)) { 2128 struct rpc_xprt *saved = task->tk_xprt; 2129 struct rpc_xprt_switch *xps; 2130 2131 rcu_read_lock(); 2132 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2133 rcu_read_unlock(); 2134 if (xps->xps_nxprts > 1) { 2135 long value; 2136 2137 xprt_release(task); 2138 value = atomic_long_dec_return(&xprt->queuelen); 2139 if (value == 0) 2140 rpc_xprt_switch_remove_xprt(xps, saved); 2141 xprt_put(saved); 2142 task->tk_xprt = NULL; 2143 task->tk_action = call_start; 2144 } 2145 xprt_switch_put(xps); 2146 if (!task->tk_xprt) 2147 return; 2148 } 2149 goto out_retry; 2150 case -ENOBUFS: 2151 rpc_delay(task, HZ >> 2); 2152 goto out_retry; 2153 } 2154 rpc_call_rpcerror(task, status); 2155 return; 2156 out_next: 2157 task->tk_action = call_transmit; 2158 return; 2159 out_retry: 2160 /* Check for timeouts before looping back to call_bind */ 2161 task->tk_action = call_bind; 2162 rpc_check_timeout(task); 2163 } 2164 2165 /* 2166 * 5. Transmit the RPC request, and wait for reply 2167 */ 2168 static void 2169 call_transmit(struct rpc_task *task) 2170 { 2171 if (rpc_task_transmitted(task)) { 2172 rpc_task_handle_transmitted(task); 2173 return; 2174 } 2175 2176 task->tk_action = call_transmit_status; 2177 if (!xprt_prepare_transmit(task)) 2178 return; 2179 task->tk_status = 0; 2180 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2181 if (!xprt_connected(task->tk_xprt)) { 2182 task->tk_status = -ENOTCONN; 2183 return; 2184 } 2185 xprt_transmit(task); 2186 } 2187 xprt_end_transmit(task); 2188 } 2189 2190 /* 2191 * 5a. Handle cleanup after a transmission 2192 */ 2193 static void 2194 call_transmit_status(struct rpc_task *task) 2195 { 2196 task->tk_action = call_status; 2197 2198 /* 2199 * Common case: success. Force the compiler to put this 2200 * test first. 2201 */ 2202 if (rpc_task_transmitted(task)) { 2203 task->tk_status = 0; 2204 xprt_request_wait_receive(task); 2205 return; 2206 } 2207 2208 switch (task->tk_status) { 2209 default: 2210 break; 2211 case -EBADMSG: 2212 task->tk_status = 0; 2213 task->tk_action = call_encode; 2214 break; 2215 /* 2216 * Special cases: if we've been waiting on the 2217 * socket's write_space() callback, or if the 2218 * socket just returned a connection error, 2219 * then hold onto the transport lock. 2220 */ 2221 case -ENOMEM: 2222 case -ENOBUFS: 2223 rpc_delay(task, HZ>>2); 2224 fallthrough; 2225 case -EBADSLT: 2226 case -EAGAIN: 2227 task->tk_action = call_transmit; 2228 task->tk_status = 0; 2229 break; 2230 case -ECONNREFUSED: 2231 case -EHOSTDOWN: 2232 case -ENETDOWN: 2233 case -EHOSTUNREACH: 2234 case -ENETUNREACH: 2235 case -EPERM: 2236 if (RPC_IS_SOFTCONN(task)) { 2237 if (!task->tk_msg.rpc_proc->p_proc) 2238 trace_xprt_ping(task->tk_xprt, 2239 task->tk_status); 2240 rpc_call_rpcerror(task, task->tk_status); 2241 return; 2242 } 2243 fallthrough; 2244 case -ECONNRESET: 2245 case -ECONNABORTED: 2246 case -EADDRINUSE: 2247 case -ENOTCONN: 2248 case -EPIPE: 2249 task->tk_action = call_bind; 2250 task->tk_status = 0; 2251 break; 2252 } 2253 rpc_check_timeout(task); 2254 } 2255 2256 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2257 static void call_bc_transmit(struct rpc_task *task); 2258 static void call_bc_transmit_status(struct rpc_task *task); 2259 2260 static void 2261 call_bc_encode(struct rpc_task *task) 2262 { 2263 xprt_request_enqueue_transmit(task); 2264 task->tk_action = call_bc_transmit; 2265 } 2266 2267 /* 2268 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2269 * addition, disconnect on connectivity errors. 2270 */ 2271 static void 2272 call_bc_transmit(struct rpc_task *task) 2273 { 2274 task->tk_action = call_bc_transmit_status; 2275 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2276 if (!xprt_prepare_transmit(task)) 2277 return; 2278 task->tk_status = 0; 2279 xprt_transmit(task); 2280 } 2281 xprt_end_transmit(task); 2282 } 2283 2284 static void 2285 call_bc_transmit_status(struct rpc_task *task) 2286 { 2287 struct rpc_rqst *req = task->tk_rqstp; 2288 2289 if (rpc_task_transmitted(task)) 2290 task->tk_status = 0; 2291 2292 switch (task->tk_status) { 2293 case 0: 2294 /* Success */ 2295 case -ENETDOWN: 2296 case -EHOSTDOWN: 2297 case -EHOSTUNREACH: 2298 case -ENETUNREACH: 2299 case -ECONNRESET: 2300 case -ECONNREFUSED: 2301 case -EADDRINUSE: 2302 case -ENOTCONN: 2303 case -EPIPE: 2304 break; 2305 case -ENOMEM: 2306 case -ENOBUFS: 2307 rpc_delay(task, HZ>>2); 2308 fallthrough; 2309 case -EBADSLT: 2310 case -EAGAIN: 2311 task->tk_status = 0; 2312 task->tk_action = call_bc_transmit; 2313 return; 2314 case -ETIMEDOUT: 2315 /* 2316 * Problem reaching the server. Disconnect and let the 2317 * forechannel reestablish the connection. The server will 2318 * have to retransmit the backchannel request and we'll 2319 * reprocess it. Since these ops are idempotent, there's no 2320 * need to cache our reply at this time. 2321 */ 2322 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2323 "error: %d\n", task->tk_status); 2324 xprt_conditional_disconnect(req->rq_xprt, 2325 req->rq_connect_cookie); 2326 break; 2327 default: 2328 /* 2329 * We were unable to reply and will have to drop the 2330 * request. The server should reconnect and retransmit. 2331 */ 2332 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2333 "error: %d\n", task->tk_status); 2334 break; 2335 } 2336 task->tk_action = rpc_exit_task; 2337 } 2338 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2339 2340 /* 2341 * 6. Sort out the RPC call status 2342 */ 2343 static void 2344 call_status(struct rpc_task *task) 2345 { 2346 struct rpc_clnt *clnt = task->tk_client; 2347 int status; 2348 2349 if (!task->tk_msg.rpc_proc->p_proc) 2350 trace_xprt_ping(task->tk_xprt, task->tk_status); 2351 2352 status = task->tk_status; 2353 if (status >= 0) { 2354 task->tk_action = call_decode; 2355 return; 2356 } 2357 2358 trace_rpc_call_status(task); 2359 task->tk_status = 0; 2360 switch(status) { 2361 case -EHOSTDOWN: 2362 case -ENETDOWN: 2363 case -EHOSTUNREACH: 2364 case -ENETUNREACH: 2365 case -EPERM: 2366 if (RPC_IS_SOFTCONN(task)) 2367 goto out_exit; 2368 /* 2369 * Delay any retries for 3 seconds, then handle as if it 2370 * were a timeout. 2371 */ 2372 rpc_delay(task, 3*HZ); 2373 fallthrough; 2374 case -ETIMEDOUT: 2375 break; 2376 case -ECONNREFUSED: 2377 case -ECONNRESET: 2378 case -ECONNABORTED: 2379 case -ENOTCONN: 2380 rpc_force_rebind(clnt); 2381 break; 2382 case -EADDRINUSE: 2383 rpc_delay(task, 3*HZ); 2384 fallthrough; 2385 case -EPIPE: 2386 case -EAGAIN: 2387 break; 2388 case -ENFILE: 2389 case -ENOBUFS: 2390 case -ENOMEM: 2391 rpc_delay(task, HZ>>2); 2392 break; 2393 case -EIO: 2394 /* shutdown or soft timeout */ 2395 goto out_exit; 2396 default: 2397 if (clnt->cl_chatty) 2398 printk("%s: RPC call returned error %d\n", 2399 clnt->cl_program->name, -status); 2400 goto out_exit; 2401 } 2402 task->tk_action = call_encode; 2403 if (status != -ECONNRESET && status != -ECONNABORTED) 2404 rpc_check_timeout(task); 2405 return; 2406 out_exit: 2407 rpc_call_rpcerror(task, status); 2408 } 2409 2410 static bool 2411 rpc_check_connected(const struct rpc_rqst *req) 2412 { 2413 /* No allocated request or transport? return true */ 2414 if (!req || !req->rq_xprt) 2415 return true; 2416 return xprt_connected(req->rq_xprt); 2417 } 2418 2419 static void 2420 rpc_check_timeout(struct rpc_task *task) 2421 { 2422 struct rpc_clnt *clnt = task->tk_client; 2423 2424 if (RPC_SIGNALLED(task)) { 2425 rpc_call_rpcerror(task, -ERESTARTSYS); 2426 return; 2427 } 2428 2429 if (xprt_adjust_timeout(task->tk_rqstp) == 0) 2430 return; 2431 2432 trace_rpc_timeout_status(task); 2433 task->tk_timeouts++; 2434 2435 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) { 2436 rpc_call_rpcerror(task, -ETIMEDOUT); 2437 return; 2438 } 2439 2440 if (RPC_IS_SOFT(task)) { 2441 /* 2442 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has 2443 * been sent, it should time out only if the transport 2444 * connection gets terminally broken. 2445 */ 2446 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && 2447 rpc_check_connected(task->tk_rqstp)) 2448 return; 2449 2450 if (clnt->cl_chatty) { 2451 pr_notice_ratelimited( 2452 "%s: server %s not responding, timed out\n", 2453 clnt->cl_program->name, 2454 task->tk_xprt->servername); 2455 } 2456 if (task->tk_flags & RPC_TASK_TIMEOUT) 2457 rpc_call_rpcerror(task, -ETIMEDOUT); 2458 else 2459 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT); 2460 return; 2461 } 2462 2463 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2464 task->tk_flags |= RPC_CALL_MAJORSEEN; 2465 if (clnt->cl_chatty) { 2466 pr_notice_ratelimited( 2467 "%s: server %s not responding, still trying\n", 2468 clnt->cl_program->name, 2469 task->tk_xprt->servername); 2470 } 2471 } 2472 rpc_force_rebind(clnt); 2473 /* 2474 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2475 * event? RFC2203 requires the server to drop all such requests. 2476 */ 2477 rpcauth_invalcred(task); 2478 } 2479 2480 /* 2481 * 7. Decode the RPC reply 2482 */ 2483 static void 2484 call_decode(struct rpc_task *task) 2485 { 2486 struct rpc_clnt *clnt = task->tk_client; 2487 struct rpc_rqst *req = task->tk_rqstp; 2488 struct xdr_stream xdr; 2489 int err; 2490 2491 if (!task->tk_msg.rpc_proc->p_decode) { 2492 task->tk_action = rpc_exit_task; 2493 return; 2494 } 2495 2496 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2497 if (clnt->cl_chatty) { 2498 pr_notice_ratelimited("%s: server %s OK\n", 2499 clnt->cl_program->name, 2500 task->tk_xprt->servername); 2501 } 2502 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2503 } 2504 2505 /* 2506 * Did we ever call xprt_complete_rqst()? If not, we should assume 2507 * the message is incomplete. 2508 */ 2509 err = -EAGAIN; 2510 if (!req->rq_reply_bytes_recvd) 2511 goto out; 2512 2513 /* Ensure that we see all writes made by xprt_complete_rqst() 2514 * before it changed req->rq_reply_bytes_recvd. 2515 */ 2516 smp_rmb(); 2517 2518 req->rq_rcv_buf.len = req->rq_private_buf.len; 2519 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf); 2520 2521 /* Check that the softirq receive buffer is valid */ 2522 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2523 sizeof(req->rq_rcv_buf)) != 0); 2524 2525 xdr_init_decode(&xdr, &req->rq_rcv_buf, 2526 req->rq_rcv_buf.head[0].iov_base, req); 2527 err = rpc_decode_header(task, &xdr); 2528 out: 2529 switch (err) { 2530 case 0: 2531 task->tk_action = rpc_exit_task; 2532 task->tk_status = rpcauth_unwrap_resp(task, &xdr); 2533 return; 2534 case -EAGAIN: 2535 task->tk_status = 0; 2536 if (task->tk_client->cl_discrtry) 2537 xprt_conditional_disconnect(req->rq_xprt, 2538 req->rq_connect_cookie); 2539 task->tk_action = call_encode; 2540 rpc_check_timeout(task); 2541 break; 2542 case -EKEYREJECTED: 2543 task->tk_action = call_reserve; 2544 rpc_check_timeout(task); 2545 rpcauth_invalcred(task); 2546 /* Ensure we obtain a new XID if we retry! */ 2547 xprt_release(task); 2548 } 2549 } 2550 2551 static int 2552 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr) 2553 { 2554 struct rpc_clnt *clnt = task->tk_client; 2555 struct rpc_rqst *req = task->tk_rqstp; 2556 __be32 *p; 2557 int error; 2558 2559 error = -EMSGSIZE; 2560 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2); 2561 if (!p) 2562 goto out_fail; 2563 *p++ = req->rq_xid; 2564 *p++ = rpc_call; 2565 *p++ = cpu_to_be32(RPC_VERSION); 2566 *p++ = cpu_to_be32(clnt->cl_prog); 2567 *p++ = cpu_to_be32(clnt->cl_vers); 2568 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc); 2569 2570 error = rpcauth_marshcred(task, xdr); 2571 if (error < 0) 2572 goto out_fail; 2573 return 0; 2574 out_fail: 2575 trace_rpc_bad_callhdr(task); 2576 rpc_call_rpcerror(task, error); 2577 return error; 2578 } 2579 2580 static noinline int 2581 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) 2582 { 2583 struct rpc_clnt *clnt = task->tk_client; 2584 int error; 2585 __be32 *p; 2586 2587 /* RFC-1014 says that the representation of XDR data must be a 2588 * multiple of four bytes 2589 * - if it isn't pointer subtraction in the NFS client may give 2590 * undefined results 2591 */ 2592 if (task->tk_rqstp->rq_rcv_buf.len & 3) 2593 goto out_unparsable; 2594 2595 p = xdr_inline_decode(xdr, 3 * sizeof(*p)); 2596 if (!p) 2597 goto out_unparsable; 2598 p++; /* skip XID */ 2599 if (*p++ != rpc_reply) 2600 goto out_unparsable; 2601 if (*p++ != rpc_msg_accepted) 2602 goto out_msg_denied; 2603 2604 error = rpcauth_checkverf(task, xdr); 2605 if (error) 2606 goto out_verifier; 2607 2608 p = xdr_inline_decode(xdr, sizeof(*p)); 2609 if (!p) 2610 goto out_unparsable; 2611 switch (*p) { 2612 case rpc_success: 2613 return 0; 2614 case rpc_prog_unavail: 2615 trace_rpc__prog_unavail(task); 2616 error = -EPFNOSUPPORT; 2617 goto out_err; 2618 case rpc_prog_mismatch: 2619 trace_rpc__prog_mismatch(task); 2620 error = -EPROTONOSUPPORT; 2621 goto out_err; 2622 case rpc_proc_unavail: 2623 trace_rpc__proc_unavail(task); 2624 error = -EOPNOTSUPP; 2625 goto out_err; 2626 case rpc_garbage_args: 2627 case rpc_system_err: 2628 trace_rpc__garbage_args(task); 2629 error = -EIO; 2630 break; 2631 default: 2632 goto out_unparsable; 2633 } 2634 2635 out_garbage: 2636 clnt->cl_stats->rpcgarbage++; 2637 if (task->tk_garb_retry) { 2638 task->tk_garb_retry--; 2639 task->tk_action = call_encode; 2640 return -EAGAIN; 2641 } 2642 out_err: 2643 rpc_call_rpcerror(task, error); 2644 return error; 2645 2646 out_unparsable: 2647 trace_rpc__unparsable(task); 2648 error = -EIO; 2649 goto out_garbage; 2650 2651 out_verifier: 2652 trace_rpc_bad_verifier(task); 2653 goto out_garbage; 2654 2655 out_msg_denied: 2656 error = -EACCES; 2657 p = xdr_inline_decode(xdr, sizeof(*p)); 2658 if (!p) 2659 goto out_unparsable; 2660 switch (*p++) { 2661 case rpc_auth_error: 2662 break; 2663 case rpc_mismatch: 2664 trace_rpc__mismatch(task); 2665 error = -EPROTONOSUPPORT; 2666 goto out_err; 2667 default: 2668 goto out_unparsable; 2669 } 2670 2671 p = xdr_inline_decode(xdr, sizeof(*p)); 2672 if (!p) 2673 goto out_unparsable; 2674 switch (*p++) { 2675 case rpc_autherr_rejectedcred: 2676 case rpc_autherr_rejectedverf: 2677 case rpcsec_gsserr_credproblem: 2678 case rpcsec_gsserr_ctxproblem: 2679 if (!task->tk_cred_retry) 2680 break; 2681 task->tk_cred_retry--; 2682 trace_rpc__stale_creds(task); 2683 return -EKEYREJECTED; 2684 case rpc_autherr_badcred: 2685 case rpc_autherr_badverf: 2686 /* possibly garbled cred/verf? */ 2687 if (!task->tk_garb_retry) 2688 break; 2689 task->tk_garb_retry--; 2690 trace_rpc__bad_creds(task); 2691 task->tk_action = call_encode; 2692 return -EAGAIN; 2693 case rpc_autherr_tooweak: 2694 trace_rpc__auth_tooweak(task); 2695 pr_warn("RPC: server %s requires stronger authentication.\n", 2696 task->tk_xprt->servername); 2697 break; 2698 default: 2699 goto out_unparsable; 2700 } 2701 goto out_err; 2702 } 2703 2704 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2705 const void *obj) 2706 { 2707 } 2708 2709 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2710 void *obj) 2711 { 2712 return 0; 2713 } 2714 2715 static const struct rpc_procinfo rpcproc_null = { 2716 .p_encode = rpcproc_encode_null, 2717 .p_decode = rpcproc_decode_null, 2718 }; 2719 2720 static const struct rpc_procinfo rpcproc_null_noreply = { 2721 .p_encode = rpcproc_encode_null, 2722 }; 2723 2724 static void 2725 rpc_null_call_prepare(struct rpc_task *task, void *data) 2726 { 2727 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT; 2728 rpc_call_start(task); 2729 } 2730 2731 static const struct rpc_call_ops rpc_null_ops = { 2732 .rpc_call_prepare = rpc_null_call_prepare, 2733 .rpc_call_done = rpc_default_callback, 2734 }; 2735 2736 static 2737 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2738 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2739 const struct rpc_call_ops *ops, void *data) 2740 { 2741 struct rpc_message msg = { 2742 .rpc_proc = &rpcproc_null, 2743 }; 2744 struct rpc_task_setup task_setup_data = { 2745 .rpc_client = clnt, 2746 .rpc_xprt = xprt, 2747 .rpc_message = &msg, 2748 .rpc_op_cred = cred, 2749 .callback_ops = ops ?: &rpc_null_ops, 2750 .callback_data = data, 2751 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN | 2752 RPC_TASK_NULLCREDS, 2753 }; 2754 2755 return rpc_run_task(&task_setup_data); 2756 } 2757 2758 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2759 { 2760 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2761 } 2762 EXPORT_SYMBOL_GPL(rpc_call_null); 2763 2764 static int rpc_ping(struct rpc_clnt *clnt) 2765 { 2766 struct rpc_task *task; 2767 int status; 2768 2769 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL); 2770 if (IS_ERR(task)) 2771 return PTR_ERR(task); 2772 status = task->tk_status; 2773 rpc_put_task(task); 2774 return status; 2775 } 2776 2777 static int rpc_ping_noreply(struct rpc_clnt *clnt) 2778 { 2779 struct rpc_message msg = { 2780 .rpc_proc = &rpcproc_null_noreply, 2781 }; 2782 struct rpc_task_setup task_setup_data = { 2783 .rpc_client = clnt, 2784 .rpc_message = &msg, 2785 .callback_ops = &rpc_null_ops, 2786 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS, 2787 }; 2788 struct rpc_task *task; 2789 int status; 2790 2791 task = rpc_run_task(&task_setup_data); 2792 if (IS_ERR(task)) 2793 return PTR_ERR(task); 2794 status = task->tk_status; 2795 rpc_put_task(task); 2796 return status; 2797 } 2798 2799 struct rpc_cb_add_xprt_calldata { 2800 struct rpc_xprt_switch *xps; 2801 struct rpc_xprt *xprt; 2802 }; 2803 2804 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2805 { 2806 struct rpc_cb_add_xprt_calldata *data = calldata; 2807 2808 if (task->tk_status == 0) 2809 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2810 } 2811 2812 static void rpc_cb_add_xprt_release(void *calldata) 2813 { 2814 struct rpc_cb_add_xprt_calldata *data = calldata; 2815 2816 xprt_put(data->xprt); 2817 xprt_switch_put(data->xps); 2818 kfree(data); 2819 } 2820 2821 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2822 .rpc_call_prepare = rpc_null_call_prepare, 2823 .rpc_call_done = rpc_cb_add_xprt_done, 2824 .rpc_release = rpc_cb_add_xprt_release, 2825 }; 2826 2827 /** 2828 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2829 * @clnt: pointer to struct rpc_clnt 2830 * @xps: pointer to struct rpc_xprt_switch, 2831 * @xprt: pointer struct rpc_xprt 2832 * @dummy: unused 2833 */ 2834 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2835 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2836 void *dummy) 2837 { 2838 struct rpc_cb_add_xprt_calldata *data; 2839 struct rpc_task *task; 2840 2841 if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) { 2842 rcu_read_lock(); 2843 pr_warn("SUNRPC: reached max allowed number (%d) did not add " 2844 "transport to server: %s\n", clnt->cl_max_connect, 2845 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 2846 rcu_read_unlock(); 2847 return -EINVAL; 2848 } 2849 2850 data = kmalloc(sizeof(*data), GFP_KERNEL); 2851 if (!data) 2852 return -ENOMEM; 2853 data->xps = xprt_switch_get(xps); 2854 data->xprt = xprt_get(xprt); 2855 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) { 2856 rpc_cb_add_xprt_release(data); 2857 goto success; 2858 } 2859 2860 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC, 2861 &rpc_cb_add_xprt_call_ops, data); 2862 data->xps->xps_nunique_destaddr_xprts++; 2863 rpc_put_task(task); 2864 success: 2865 return 1; 2866 } 2867 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2868 2869 /** 2870 * rpc_clnt_setup_test_and_add_xprt() 2871 * 2872 * This is an rpc_clnt_add_xprt setup() function which returns 1 so: 2873 * 1) caller of the test function must dereference the rpc_xprt_switch 2874 * and the rpc_xprt. 2875 * 2) test function must call rpc_xprt_switch_add_xprt, usually in 2876 * the rpc_call_done routine. 2877 * 2878 * Upon success (return of 1), the test function adds the new 2879 * transport to the rpc_clnt xprt switch 2880 * 2881 * @clnt: struct rpc_clnt to get the new transport 2882 * @xps: the rpc_xprt_switch to hold the new transport 2883 * @xprt: the rpc_xprt to test 2884 * @data: a struct rpc_add_xprt_test pointer that holds the test function 2885 * and test function call data 2886 */ 2887 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, 2888 struct rpc_xprt_switch *xps, 2889 struct rpc_xprt *xprt, 2890 void *data) 2891 { 2892 struct rpc_task *task; 2893 struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data; 2894 int status = -EADDRINUSE; 2895 2896 xprt = xprt_get(xprt); 2897 xprt_switch_get(xps); 2898 2899 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) 2900 goto out_err; 2901 2902 /* Test the connection */ 2903 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL); 2904 if (IS_ERR(task)) { 2905 status = PTR_ERR(task); 2906 goto out_err; 2907 } 2908 status = task->tk_status; 2909 rpc_put_task(task); 2910 2911 if (status < 0) 2912 goto out_err; 2913 2914 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ 2915 xtest->add_xprt_test(clnt, xprt, xtest->data); 2916 2917 xprt_put(xprt); 2918 xprt_switch_put(xps); 2919 2920 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ 2921 return 1; 2922 out_err: 2923 xprt_put(xprt); 2924 xprt_switch_put(xps); 2925 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n", 2926 status, xprt->address_strings[RPC_DISPLAY_ADDR]); 2927 return status; 2928 } 2929 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); 2930 2931 /** 2932 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 2933 * @clnt: pointer to struct rpc_clnt 2934 * @xprtargs: pointer to struct xprt_create 2935 * @setup: callback to test and/or set up the connection 2936 * @data: pointer to setup function data 2937 * 2938 * Creates a new transport using the parameters set in args and 2939 * adds it to clnt. 2940 * If ping is set, then test that connectivity succeeds before 2941 * adding the new transport. 2942 * 2943 */ 2944 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 2945 struct xprt_create *xprtargs, 2946 int (*setup)(struct rpc_clnt *, 2947 struct rpc_xprt_switch *, 2948 struct rpc_xprt *, 2949 void *), 2950 void *data) 2951 { 2952 struct rpc_xprt_switch *xps; 2953 struct rpc_xprt *xprt; 2954 unsigned long connect_timeout; 2955 unsigned long reconnect_timeout; 2956 unsigned char resvport, reuseport; 2957 int ret = 0, ident; 2958 2959 rcu_read_lock(); 2960 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2961 xprt = xprt_iter_xprt(&clnt->cl_xpi); 2962 if (xps == NULL || xprt == NULL) { 2963 rcu_read_unlock(); 2964 xprt_switch_put(xps); 2965 return -EAGAIN; 2966 } 2967 resvport = xprt->resvport; 2968 reuseport = xprt->reuseport; 2969 connect_timeout = xprt->connect_timeout; 2970 reconnect_timeout = xprt->max_reconnect_timeout; 2971 ident = xprt->xprt_class->ident; 2972 rcu_read_unlock(); 2973 2974 if (!xprtargs->ident) 2975 xprtargs->ident = ident; 2976 xprt = xprt_create_transport(xprtargs); 2977 if (IS_ERR(xprt)) { 2978 ret = PTR_ERR(xprt); 2979 goto out_put_switch; 2980 } 2981 xprt->resvport = resvport; 2982 xprt->reuseport = reuseport; 2983 if (xprt->ops->set_connect_timeout != NULL) 2984 xprt->ops->set_connect_timeout(xprt, 2985 connect_timeout, 2986 reconnect_timeout); 2987 2988 rpc_xprt_switch_set_roundrobin(xps); 2989 if (setup) { 2990 ret = setup(clnt, xps, xprt, data); 2991 if (ret != 0) 2992 goto out_put_xprt; 2993 } 2994 rpc_xprt_switch_add_xprt(xps, xprt); 2995 out_put_xprt: 2996 xprt_put(xprt); 2997 out_put_switch: 2998 xprt_switch_put(xps); 2999 return ret; 3000 } 3001 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 3002 3003 struct connect_timeout_data { 3004 unsigned long connect_timeout; 3005 unsigned long reconnect_timeout; 3006 }; 3007 3008 static int 3009 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, 3010 struct rpc_xprt *xprt, 3011 void *data) 3012 { 3013 struct connect_timeout_data *timeo = data; 3014 3015 if (xprt->ops->set_connect_timeout) 3016 xprt->ops->set_connect_timeout(xprt, 3017 timeo->connect_timeout, 3018 timeo->reconnect_timeout); 3019 return 0; 3020 } 3021 3022 void 3023 rpc_set_connect_timeout(struct rpc_clnt *clnt, 3024 unsigned long connect_timeout, 3025 unsigned long reconnect_timeout) 3026 { 3027 struct connect_timeout_data timeout = { 3028 .connect_timeout = connect_timeout, 3029 .reconnect_timeout = reconnect_timeout, 3030 }; 3031 rpc_clnt_iterate_for_each_xprt(clnt, 3032 rpc_xprt_set_connect_timeout, 3033 &timeout); 3034 } 3035 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); 3036 3037 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt) 3038 { 3039 rcu_read_lock(); 3040 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3041 rcu_read_unlock(); 3042 } 3043 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put); 3044 3045 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3046 { 3047 rcu_read_lock(); 3048 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3049 xprt); 3050 rcu_read_unlock(); 3051 } 3052 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); 3053 3054 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, 3055 const struct sockaddr *sap) 3056 { 3057 struct rpc_xprt_switch *xps; 3058 bool ret; 3059 3060 rcu_read_lock(); 3061 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3062 ret = rpc_xprt_switch_has_addr(xps, sap); 3063 rcu_read_unlock(); 3064 return ret; 3065 } 3066 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); 3067 3068 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3069 static void rpc_show_header(void) 3070 { 3071 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 3072 "-timeout ---ops--\n"); 3073 } 3074 3075 static void rpc_show_task(const struct rpc_clnt *clnt, 3076 const struct rpc_task *task) 3077 { 3078 const char *rpc_waitq = "none"; 3079 3080 if (RPC_IS_QUEUED(task)) 3081 rpc_waitq = rpc_qname(task->tk_waitqueue); 3082 3083 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 3084 task->tk_pid, task->tk_flags, task->tk_status, 3085 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops, 3086 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 3087 task->tk_action, rpc_waitq); 3088 } 3089 3090 void rpc_show_tasks(struct net *net) 3091 { 3092 struct rpc_clnt *clnt; 3093 struct rpc_task *task; 3094 int header = 0; 3095 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 3096 3097 spin_lock(&sn->rpc_client_lock); 3098 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 3099 spin_lock(&clnt->cl_lock); 3100 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 3101 if (!header) { 3102 rpc_show_header(); 3103 header++; 3104 } 3105 rpc_show_task(clnt, task); 3106 } 3107 spin_unlock(&clnt->cl_lock); 3108 } 3109 spin_unlock(&sn->rpc_client_lock); 3110 } 3111 #endif 3112 3113 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 3114 static int 3115 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 3116 struct rpc_xprt *xprt, 3117 void *dummy) 3118 { 3119 return xprt_enable_swap(xprt); 3120 } 3121 3122 int 3123 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 3124 { 3125 while (clnt != clnt->cl_parent) 3126 clnt = clnt->cl_parent; 3127 if (atomic_inc_return(&clnt->cl_swapper) == 1) 3128 return rpc_clnt_iterate_for_each_xprt(clnt, 3129 rpc_clnt_swap_activate_callback, NULL); 3130 return 0; 3131 } 3132 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 3133 3134 static int 3135 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 3136 struct rpc_xprt *xprt, 3137 void *dummy) 3138 { 3139 xprt_disable_swap(xprt); 3140 return 0; 3141 } 3142 3143 void 3144 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 3145 { 3146 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 3147 rpc_clnt_iterate_for_each_xprt(clnt, 3148 rpc_clnt_swap_deactivate_callback, NULL); 3149 } 3150 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 3151 #endif /* CONFIG_SUNRPC_SWAP */ 3152