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 if (pipefs_sb == clnt->pipefs_sb) 115 __rpc_clnt_remove_pipedir(clnt); 116 rpc_put_sb_net(net); 117 } 118 } 119 120 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 121 struct rpc_clnt *clnt) 122 { 123 static uint32_t clntid; 124 const char *dir_name = clnt->cl_program->pipe_dir_name; 125 char name[15]; 126 struct dentry *dir, *dentry; 127 128 dir = rpc_d_lookup_sb(sb, dir_name); 129 if (dir == NULL) { 130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 131 return dir; 132 } 133 for (;;) { 134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 135 name[sizeof(name) - 1] = '\0'; 136 dentry = rpc_create_client_dir(dir, name, clnt); 137 if (!IS_ERR(dentry)) 138 break; 139 if (dentry == ERR_PTR(-EEXIST)) 140 continue; 141 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 142 " %s/%s, error %ld\n", 143 dir_name, name, PTR_ERR(dentry)); 144 break; 145 } 146 dput(dir); 147 return dentry; 148 } 149 150 static int 151 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt) 152 { 153 struct dentry *dentry; 154 155 clnt->pipefs_sb = pipefs_sb; 156 157 if (clnt->cl_program->pipe_dir_name != NULL) { 158 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); 159 if (IS_ERR(dentry)) 160 return PTR_ERR(dentry); 161 } 162 return 0; 163 } 164 165 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 166 { 167 if (clnt->cl_program->pipe_dir_name == NULL) 168 return 1; 169 170 switch (event) { 171 case RPC_PIPEFS_MOUNT: 172 if (clnt->cl_pipedir_objects.pdh_dentry != NULL) 173 return 1; 174 if (refcount_read(&clnt->cl_count) == 0) 175 return 1; 176 break; 177 case RPC_PIPEFS_UMOUNT: 178 if (clnt->cl_pipedir_objects.pdh_dentry == NULL) 179 return 1; 180 break; 181 } 182 return 0; 183 } 184 185 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 186 struct super_block *sb) 187 { 188 struct dentry *dentry; 189 190 switch (event) { 191 case RPC_PIPEFS_MOUNT: 192 dentry = rpc_setup_pipedir_sb(sb, clnt); 193 if (!dentry) 194 return -ENOENT; 195 if (IS_ERR(dentry)) 196 return PTR_ERR(dentry); 197 break; 198 case RPC_PIPEFS_UMOUNT: 199 __rpc_clnt_remove_pipedir(clnt); 200 break; 201 default: 202 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 203 return -ENOTSUPP; 204 } 205 return 0; 206 } 207 208 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 209 struct super_block *sb) 210 { 211 int error = 0; 212 213 for (;; clnt = clnt->cl_parent) { 214 if (!rpc_clnt_skip_event(clnt, event)) 215 error = __rpc_clnt_handle_event(clnt, event, sb); 216 if (error || clnt == clnt->cl_parent) 217 break; 218 } 219 return error; 220 } 221 222 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 223 { 224 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 225 struct rpc_clnt *clnt; 226 227 spin_lock(&sn->rpc_client_lock); 228 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 229 if (rpc_clnt_skip_event(clnt, event)) 230 continue; 231 spin_unlock(&sn->rpc_client_lock); 232 return clnt; 233 } 234 spin_unlock(&sn->rpc_client_lock); 235 return NULL; 236 } 237 238 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 239 void *ptr) 240 { 241 struct super_block *sb = ptr; 242 struct rpc_clnt *clnt; 243 int error = 0; 244 245 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 246 error = __rpc_pipefs_event(clnt, event, sb); 247 if (error) 248 break; 249 } 250 return error; 251 } 252 253 static struct notifier_block rpc_clients_block = { 254 .notifier_call = rpc_pipefs_event, 255 .priority = SUNRPC_PIPEFS_RPC_PRIO, 256 }; 257 258 int rpc_clients_notifier_register(void) 259 { 260 return rpc_pipefs_notifier_register(&rpc_clients_block); 261 } 262 263 void rpc_clients_notifier_unregister(void) 264 { 265 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 266 } 267 268 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, 269 struct rpc_xprt *xprt, 270 const struct rpc_timeout *timeout) 271 { 272 struct rpc_xprt *old; 273 274 spin_lock(&clnt->cl_lock); 275 old = rcu_dereference_protected(clnt->cl_xprt, 276 lockdep_is_held(&clnt->cl_lock)); 277 278 if (!xprt_bound(xprt)) 279 clnt->cl_autobind = 1; 280 281 clnt->cl_timeout = timeout; 282 rcu_assign_pointer(clnt->cl_xprt, xprt); 283 spin_unlock(&clnt->cl_lock); 284 285 return old; 286 } 287 288 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 289 { 290 ssize_t copied; 291 292 copied = strscpy(clnt->cl_nodename, 293 nodename, sizeof(clnt->cl_nodename)); 294 295 clnt->cl_nodelen = copied < 0 296 ? sizeof(clnt->cl_nodename) - 1 297 : copied; 298 } 299 300 static int rpc_client_register(struct rpc_clnt *clnt, 301 rpc_authflavor_t pseudoflavor, 302 const char *client_name) 303 { 304 struct rpc_auth_create_args auth_args = { 305 .pseudoflavor = pseudoflavor, 306 .target_name = client_name, 307 }; 308 struct rpc_auth *auth; 309 struct net *net = rpc_net_ns(clnt); 310 struct super_block *pipefs_sb; 311 int err; 312 313 rpc_clnt_debugfs_register(clnt); 314 315 pipefs_sb = rpc_get_sb_net(net); 316 if (pipefs_sb) { 317 err = rpc_setup_pipedir(pipefs_sb, clnt); 318 if (err) 319 goto out; 320 } 321 322 rpc_register_client(clnt); 323 if (pipefs_sb) 324 rpc_put_sb_net(net); 325 326 auth = rpcauth_create(&auth_args, clnt); 327 if (IS_ERR(auth)) { 328 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 329 pseudoflavor); 330 err = PTR_ERR(auth); 331 goto err_auth; 332 } 333 return 0; 334 err_auth: 335 pipefs_sb = rpc_get_sb_net(net); 336 rpc_unregister_client(clnt); 337 __rpc_clnt_remove_pipedir(clnt); 338 out: 339 if (pipefs_sb) 340 rpc_put_sb_net(net); 341 rpc_sysfs_client_destroy(clnt); 342 rpc_clnt_debugfs_unregister(clnt); 343 return err; 344 } 345 346 static DEFINE_IDA(rpc_clids); 347 348 void rpc_cleanup_clids(void) 349 { 350 ida_destroy(&rpc_clids); 351 } 352 353 static int rpc_alloc_clid(struct rpc_clnt *clnt) 354 { 355 int clid; 356 357 clid = ida_alloc(&rpc_clids, GFP_KERNEL); 358 if (clid < 0) 359 return clid; 360 clnt->cl_clid = clid; 361 return 0; 362 } 363 364 static void rpc_free_clid(struct rpc_clnt *clnt) 365 { 366 ida_free(&rpc_clids, clnt->cl_clid); 367 } 368 369 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 370 struct rpc_xprt_switch *xps, 371 struct rpc_xprt *xprt, 372 struct rpc_clnt *parent) 373 { 374 const struct rpc_program *program = args->program; 375 const struct rpc_version *version; 376 struct rpc_clnt *clnt = NULL; 377 const struct rpc_timeout *timeout; 378 const char *nodename = args->nodename; 379 int err; 380 381 err = rpciod_up(); 382 if (err) 383 goto out_no_rpciod; 384 385 err = -EINVAL; 386 if (args->version >= program->nrvers) 387 goto out_err; 388 version = program->version[args->version]; 389 if (version == NULL) 390 goto out_err; 391 392 err = -ENOMEM; 393 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 394 if (!clnt) 395 goto out_err; 396 clnt->cl_parent = parent ? : clnt; 397 clnt->cl_xprtsec = args->xprtsec; 398 399 err = rpc_alloc_clid(clnt); 400 if (err) 401 goto out_no_clid; 402 403 clnt->cl_cred = get_cred(args->cred); 404 clnt->cl_procinfo = version->procs; 405 clnt->cl_maxproc = version->nrprocs; 406 clnt->cl_prog = args->prognumber ? : program->number; 407 clnt->cl_vers = version->number; 408 clnt->cl_stats = args->stats ? : program->stats; 409 clnt->cl_metrics = rpc_alloc_iostats(clnt); 410 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 411 err = -ENOMEM; 412 if (clnt->cl_metrics == NULL) 413 goto out_no_stats; 414 clnt->cl_program = program; 415 INIT_LIST_HEAD(&clnt->cl_tasks); 416 spin_lock_init(&clnt->cl_lock); 417 418 timeout = xprt->timeout; 419 if (args->timeout != NULL) { 420 memcpy(&clnt->cl_timeout_default, args->timeout, 421 sizeof(clnt->cl_timeout_default)); 422 timeout = &clnt->cl_timeout_default; 423 } 424 425 rpc_clnt_set_transport(clnt, xprt, timeout); 426 xprt->main = true; 427 xprt_iter_init(&clnt->cl_xpi, xps); 428 xprt_switch_put(xps); 429 430 clnt->cl_rtt = &clnt->cl_rtt_default; 431 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 432 433 refcount_set(&clnt->cl_count, 1); 434 435 if (nodename == NULL) 436 nodename = utsname()->nodename; 437 /* save the nodename */ 438 rpc_clnt_set_nodename(clnt, nodename); 439 440 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt)); 441 err = rpc_client_register(clnt, args->authflavor, args->client_name); 442 if (err) 443 goto out_no_path; 444 if (parent) 445 refcount_inc(&parent->cl_count); 446 447 trace_rpc_clnt_new(clnt, xprt, args); 448 return clnt; 449 450 out_no_path: 451 rpc_free_iostats(clnt->cl_metrics); 452 out_no_stats: 453 put_cred(clnt->cl_cred); 454 rpc_free_clid(clnt); 455 out_no_clid: 456 kfree(clnt); 457 out_err: 458 rpciod_down(); 459 out_no_rpciod: 460 xprt_switch_put(xps); 461 xprt_put(xprt); 462 trace_rpc_clnt_new_err(program->name, args->servername, err); 463 return ERR_PTR(err); 464 } 465 466 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 467 struct rpc_xprt *xprt) 468 { 469 struct rpc_clnt *clnt = NULL; 470 struct rpc_xprt_switch *xps; 471 472 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) { 473 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 474 xps = args->bc_xprt->xpt_bc_xps; 475 xprt_switch_get(xps); 476 } else { 477 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 478 if (xps == NULL) { 479 xprt_put(xprt); 480 return ERR_PTR(-ENOMEM); 481 } 482 if (xprt->bc_xprt) { 483 xprt_switch_get(xps); 484 xprt->bc_xprt->xpt_bc_xps = xps; 485 } 486 } 487 clnt = rpc_new_client(args, xps, xprt, NULL); 488 if (IS_ERR(clnt)) 489 return clnt; 490 491 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 492 int err = rpc_ping(clnt); 493 if (err != 0) { 494 rpc_shutdown_client(clnt); 495 return ERR_PTR(err); 496 } 497 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) { 498 int err = rpc_ping_noreply(clnt); 499 if (err != 0) { 500 rpc_shutdown_client(clnt); 501 return ERR_PTR(err); 502 } 503 } 504 505 clnt->cl_softrtry = 1; 506 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) { 507 clnt->cl_softrtry = 0; 508 if (args->flags & RPC_CLNT_CREATE_SOFTERR) 509 clnt->cl_softerr = 1; 510 } 511 512 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 513 clnt->cl_autobind = 1; 514 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 515 clnt->cl_noretranstimeo = 1; 516 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 517 clnt->cl_discrtry = 1; 518 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 519 clnt->cl_chatty = 1; 520 521 return clnt; 522 } 523 524 /** 525 * rpc_create - create an RPC client and transport with one call 526 * @args: rpc_clnt create argument structure 527 * 528 * Creates and initializes an RPC transport and an RPC client. 529 * 530 * It can ping the server in order to determine if it is up, and to see if 531 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 532 * this behavior so asynchronous tasks can also use rpc_create. 533 */ 534 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 535 { 536 struct rpc_xprt *xprt; 537 struct xprt_create xprtargs = { 538 .net = args->net, 539 .ident = args->protocol, 540 .srcaddr = args->saddress, 541 .dstaddr = args->address, 542 .addrlen = args->addrsize, 543 .servername = args->servername, 544 .bc_xprt = args->bc_xprt, 545 .xprtsec = args->xprtsec, 546 .connect_timeout = args->connect_timeout, 547 .reconnect_timeout = args->reconnect_timeout, 548 }; 549 char servername[48]; 550 struct rpc_clnt *clnt; 551 int i; 552 553 if (args->bc_xprt) { 554 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 555 xprt = args->bc_xprt->xpt_bc_xprt; 556 if (xprt) { 557 xprt_get(xprt); 558 return rpc_create_xprt(args, xprt); 559 } 560 } 561 562 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 563 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 564 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 565 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 566 /* 567 * If the caller chooses not to specify a hostname, whip 568 * up a string representation of the passed-in address. 569 */ 570 if (xprtargs.servername == NULL) { 571 struct sockaddr_un *sun = 572 (struct sockaddr_un *)args->address; 573 struct sockaddr_in *sin = 574 (struct sockaddr_in *)args->address; 575 struct sockaddr_in6 *sin6 = 576 (struct sockaddr_in6 *)args->address; 577 578 servername[0] = '\0'; 579 switch (args->address->sa_family) { 580 case AF_LOCAL: 581 if (sun->sun_path[0]) 582 snprintf(servername, sizeof(servername), "%s", 583 sun->sun_path); 584 else 585 snprintf(servername, sizeof(servername), "@%s", 586 sun->sun_path+1); 587 break; 588 case AF_INET: 589 snprintf(servername, sizeof(servername), "%pI4", 590 &sin->sin_addr.s_addr); 591 break; 592 case AF_INET6: 593 snprintf(servername, sizeof(servername), "%pI6", 594 &sin6->sin6_addr); 595 break; 596 default: 597 /* caller wants default server name, but 598 * address family isn't recognized. */ 599 return ERR_PTR(-EINVAL); 600 } 601 xprtargs.servername = servername; 602 } 603 604 xprt = xprt_create_transport(&xprtargs); 605 if (IS_ERR(xprt)) 606 return (struct rpc_clnt *)xprt; 607 608 /* 609 * By default, kernel RPC client connects from a reserved port. 610 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 611 * but it is always enabled for rpciod, which handles the connect 612 * operation. 613 */ 614 xprt->resvport = 1; 615 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 616 xprt->resvport = 0; 617 xprt->reuseport = 0; 618 if (args->flags & RPC_CLNT_CREATE_REUSEPORT) 619 xprt->reuseport = 1; 620 621 clnt = rpc_create_xprt(args, xprt); 622 if (IS_ERR(clnt) || args->nconnect <= 1) 623 return clnt; 624 625 for (i = 0; i < args->nconnect - 1; i++) { 626 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0) 627 break; 628 } 629 return clnt; 630 } 631 EXPORT_SYMBOL_GPL(rpc_create); 632 633 /* 634 * This function clones the RPC client structure. It allows us to share the 635 * same transport while varying parameters such as the authentication 636 * flavour. 637 */ 638 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 639 struct rpc_clnt *clnt) 640 { 641 struct rpc_xprt_switch *xps; 642 struct rpc_xprt *xprt; 643 struct rpc_clnt *new; 644 int err; 645 646 err = -ENOMEM; 647 rcu_read_lock(); 648 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 649 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 650 rcu_read_unlock(); 651 if (xprt == NULL || xps == NULL) { 652 xprt_put(xprt); 653 xprt_switch_put(xps); 654 goto out_err; 655 } 656 args->servername = xprt->servername; 657 args->nodename = clnt->cl_nodename; 658 659 new = rpc_new_client(args, xps, xprt, clnt); 660 if (IS_ERR(new)) 661 return new; 662 663 /* Turn off autobind on clones */ 664 new->cl_autobind = 0; 665 new->cl_softrtry = clnt->cl_softrtry; 666 new->cl_softerr = clnt->cl_softerr; 667 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 668 new->cl_discrtry = clnt->cl_discrtry; 669 new->cl_chatty = clnt->cl_chatty; 670 new->cl_principal = clnt->cl_principal; 671 new->cl_max_connect = clnt->cl_max_connect; 672 return new; 673 674 out_err: 675 trace_rpc_clnt_clone_err(clnt, err); 676 return ERR_PTR(err); 677 } 678 679 /** 680 * rpc_clone_client - Clone an RPC client structure 681 * 682 * @clnt: RPC client whose parameters are copied 683 * 684 * Returns a fresh RPC client or an ERR_PTR. 685 */ 686 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 687 { 688 struct rpc_create_args args = { 689 .program = clnt->cl_program, 690 .prognumber = clnt->cl_prog, 691 .version = clnt->cl_vers, 692 .authflavor = clnt->cl_auth->au_flavor, 693 .cred = clnt->cl_cred, 694 .stats = clnt->cl_stats, 695 }; 696 return __rpc_clone_client(&args, clnt); 697 } 698 EXPORT_SYMBOL_GPL(rpc_clone_client); 699 700 /** 701 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 702 * 703 * @clnt: RPC client whose parameters are copied 704 * @flavor: security flavor for new client 705 * 706 * Returns a fresh RPC client or an ERR_PTR. 707 */ 708 struct rpc_clnt * 709 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 710 { 711 struct rpc_create_args args = { 712 .program = clnt->cl_program, 713 .prognumber = clnt->cl_prog, 714 .version = clnt->cl_vers, 715 .authflavor = flavor, 716 .cred = clnt->cl_cred, 717 .stats = clnt->cl_stats, 718 }; 719 return __rpc_clone_client(&args, clnt); 720 } 721 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 722 723 /** 724 * rpc_switch_client_transport: switch the RPC transport on the fly 725 * @clnt: pointer to a struct rpc_clnt 726 * @args: pointer to the new transport arguments 727 * @timeout: pointer to the new timeout parameters 728 * 729 * This function allows the caller to switch the RPC transport for the 730 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 731 * server, for instance. It assumes that the caller has ensured that 732 * there are no active RPC tasks by using some form of locking. 733 * 734 * Returns zero if "clnt" is now using the new xprt. Otherwise a 735 * negative errno is returned, and "clnt" continues to use the old 736 * xprt. 737 */ 738 int rpc_switch_client_transport(struct rpc_clnt *clnt, 739 struct xprt_create *args, 740 const struct rpc_timeout *timeout) 741 { 742 const struct rpc_timeout *old_timeo; 743 rpc_authflavor_t pseudoflavor; 744 struct rpc_xprt_switch *xps, *oldxps; 745 struct rpc_xprt *xprt, *old; 746 struct rpc_clnt *parent; 747 int err; 748 749 args->xprtsec = clnt->cl_xprtsec; 750 xprt = xprt_create_transport(args); 751 if (IS_ERR(xprt)) 752 return PTR_ERR(xprt); 753 754 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 755 if (xps == NULL) { 756 xprt_put(xprt); 757 return -ENOMEM; 758 } 759 760 pseudoflavor = clnt->cl_auth->au_flavor; 761 762 old_timeo = clnt->cl_timeout; 763 old = rpc_clnt_set_transport(clnt, xprt, timeout); 764 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps); 765 766 rpc_unregister_client(clnt); 767 __rpc_clnt_remove_pipedir(clnt); 768 rpc_sysfs_client_destroy(clnt); 769 rpc_clnt_debugfs_unregister(clnt); 770 771 /* 772 * A new transport was created. "clnt" therefore 773 * becomes the root of a new cl_parent tree. clnt's 774 * children, if it has any, still point to the old xprt. 775 */ 776 parent = clnt->cl_parent; 777 clnt->cl_parent = clnt; 778 779 /* 780 * The old rpc_auth cache cannot be re-used. GSS 781 * contexts in particular are between a single 782 * client and server. 783 */ 784 err = rpc_client_register(clnt, pseudoflavor, NULL); 785 if (err) 786 goto out_revert; 787 788 synchronize_rcu(); 789 if (parent != clnt) 790 rpc_release_client(parent); 791 xprt_switch_put(oldxps); 792 xprt_put(old); 793 trace_rpc_clnt_replace_xprt(clnt); 794 return 0; 795 796 out_revert: 797 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps); 798 rpc_clnt_set_transport(clnt, old, old_timeo); 799 clnt->cl_parent = parent; 800 rpc_client_register(clnt, pseudoflavor, NULL); 801 xprt_switch_put(xps); 802 xprt_put(xprt); 803 trace_rpc_clnt_replace_xprt_err(clnt); 804 return err; 805 } 806 EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 807 808 static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt) 809 { 810 struct rpc_xprt_switch *xps; 811 812 rcu_read_lock(); 813 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 814 rcu_read_unlock(); 815 816 return xps; 817 } 818 819 static 820 int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi, 821 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps)) 822 { 823 struct rpc_xprt_switch *xps; 824 825 xps = rpc_clnt_xprt_switch_get(clnt); 826 if (xps == NULL) 827 return -EAGAIN; 828 func(xpi, xps); 829 xprt_switch_put(xps); 830 return 0; 831 } 832 833 static 834 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi) 835 { 836 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall); 837 } 838 839 static 840 int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt, 841 struct rpc_xprt_iter *xpi) 842 { 843 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline); 844 } 845 846 /** 847 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports 848 * @clnt: pointer to client 849 * @fn: function to apply 850 * @data: void pointer to function data 851 * 852 * Iterates through the list of RPC transports currently attached to the 853 * client and applies the function fn(clnt, xprt, data). 854 * 855 * On error, the iteration stops, and the function returns the error value. 856 */ 857 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 858 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), 859 void *data) 860 { 861 struct rpc_xprt_iter xpi; 862 int ret; 863 864 ret = rpc_clnt_xprt_iter_init(clnt, &xpi); 865 if (ret) 866 return ret; 867 for (;;) { 868 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 869 870 if (!xprt) 871 break; 872 ret = fn(clnt, xprt, data); 873 xprt_put(xprt); 874 if (ret < 0) 875 break; 876 } 877 xprt_iter_destroy(&xpi); 878 return ret; 879 } 880 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); 881 882 /* 883 * Kill all tasks for the given client. 884 * XXX: kill their descendants as well? 885 */ 886 void rpc_killall_tasks(struct rpc_clnt *clnt) 887 { 888 struct rpc_task *rovr; 889 890 891 if (list_empty(&clnt->cl_tasks)) 892 return; 893 894 /* 895 * Spin lock all_tasks to prevent changes... 896 */ 897 trace_rpc_clnt_killall(clnt); 898 spin_lock(&clnt->cl_lock); 899 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) 900 rpc_signal_task(rovr); 901 spin_unlock(&clnt->cl_lock); 902 } 903 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 904 905 /** 906 * rpc_cancel_tasks - try to cancel a set of RPC tasks 907 * @clnt: Pointer to RPC client 908 * @error: RPC task error value to set 909 * @fnmatch: Pointer to selector function 910 * @data: User data 911 * 912 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled. 913 * The argument @error must be a negative error value. 914 */ 915 unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error, 916 bool (*fnmatch)(const struct rpc_task *, 917 const void *), 918 const void *data) 919 { 920 struct rpc_task *task; 921 unsigned long count = 0; 922 923 if (list_empty(&clnt->cl_tasks)) 924 return 0; 925 /* 926 * Spin lock all_tasks to prevent changes... 927 */ 928 spin_lock(&clnt->cl_lock); 929 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 930 if (!RPC_IS_ACTIVATED(task)) 931 continue; 932 if (!fnmatch(task, data)) 933 continue; 934 rpc_task_try_cancel(task, error); 935 count++; 936 } 937 spin_unlock(&clnt->cl_lock); 938 return count; 939 } 940 EXPORT_SYMBOL_GPL(rpc_cancel_tasks); 941 942 static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt, 943 struct rpc_xprt *xprt, void *dummy) 944 { 945 if (xprt_connected(xprt)) 946 xprt_force_disconnect(xprt); 947 return 0; 948 } 949 950 void rpc_clnt_disconnect(struct rpc_clnt *clnt) 951 { 952 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL); 953 } 954 EXPORT_SYMBOL_GPL(rpc_clnt_disconnect); 955 956 /* 957 * Properly shut down an RPC client, terminating all outstanding 958 * requests. 959 */ 960 void rpc_shutdown_client(struct rpc_clnt *clnt) 961 { 962 might_sleep(); 963 964 trace_rpc_clnt_shutdown(clnt); 965 966 while (!list_empty(&clnt->cl_tasks)) { 967 rpc_killall_tasks(clnt); 968 wait_event_timeout(destroy_wait, 969 list_empty(&clnt->cl_tasks), 1*HZ); 970 } 971 972 rpc_release_client(clnt); 973 } 974 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 975 976 /* 977 * Free an RPC client 978 */ 979 static void rpc_free_client_work(struct work_struct *work) 980 { 981 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work); 982 983 trace_rpc_clnt_free(clnt); 984 985 /* These might block on processes that might allocate memory, 986 * so they cannot be called in rpciod, so they are handled separately 987 * here. 988 */ 989 rpc_sysfs_client_destroy(clnt); 990 rpc_clnt_debugfs_unregister(clnt); 991 rpc_free_clid(clnt); 992 rpc_clnt_remove_pipedir(clnt); 993 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 994 995 kfree(clnt); 996 rpciod_down(); 997 } 998 static struct rpc_clnt * 999 rpc_free_client(struct rpc_clnt *clnt) 1000 { 1001 struct rpc_clnt *parent = NULL; 1002 1003 trace_rpc_clnt_release(clnt); 1004 if (clnt->cl_parent != clnt) 1005 parent = clnt->cl_parent; 1006 rpc_unregister_client(clnt); 1007 rpc_free_iostats(clnt->cl_metrics); 1008 clnt->cl_metrics = NULL; 1009 xprt_iter_destroy(&clnt->cl_xpi); 1010 put_cred(clnt->cl_cred); 1011 1012 INIT_WORK(&clnt->cl_work, rpc_free_client_work); 1013 schedule_work(&clnt->cl_work); 1014 return parent; 1015 } 1016 1017 /* 1018 * Free an RPC client 1019 */ 1020 static struct rpc_clnt * 1021 rpc_free_auth(struct rpc_clnt *clnt) 1022 { 1023 /* 1024 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 1025 * release remaining GSS contexts. This mechanism ensures 1026 * that it can do so safely. 1027 */ 1028 if (clnt->cl_auth != NULL) { 1029 rpcauth_release(clnt->cl_auth); 1030 clnt->cl_auth = NULL; 1031 } 1032 if (refcount_dec_and_test(&clnt->cl_count)) 1033 return rpc_free_client(clnt); 1034 return NULL; 1035 } 1036 1037 /* 1038 * Release reference to the RPC client 1039 */ 1040 void 1041 rpc_release_client(struct rpc_clnt *clnt) 1042 { 1043 do { 1044 if (list_empty(&clnt->cl_tasks)) 1045 wake_up(&destroy_wait); 1046 if (refcount_dec_not_one(&clnt->cl_count)) 1047 break; 1048 clnt = rpc_free_auth(clnt); 1049 } while (clnt != NULL); 1050 } 1051 EXPORT_SYMBOL_GPL(rpc_release_client); 1052 1053 /** 1054 * rpc_bind_new_program - bind a new RPC program to an existing client 1055 * @old: old rpc_client 1056 * @program: rpc program to set 1057 * @vers: rpc program version 1058 * 1059 * Clones the rpc client and sets up a new RPC program. This is mainly 1060 * of use for enabling different RPC programs to share the same transport. 1061 * The Sun NFSv2/v3 ACL protocol can do this. 1062 */ 1063 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 1064 const struct rpc_program *program, 1065 u32 vers) 1066 { 1067 struct rpc_create_args args = { 1068 .program = program, 1069 .prognumber = program->number, 1070 .version = vers, 1071 .authflavor = old->cl_auth->au_flavor, 1072 .cred = old->cl_cred, 1073 .stats = old->cl_stats, 1074 }; 1075 struct rpc_clnt *clnt; 1076 int err; 1077 1078 clnt = __rpc_clone_client(&args, old); 1079 if (IS_ERR(clnt)) 1080 goto out; 1081 err = rpc_ping(clnt); 1082 if (err != 0) { 1083 rpc_shutdown_client(clnt); 1084 clnt = ERR_PTR(err); 1085 } 1086 out: 1087 return clnt; 1088 } 1089 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 1090 1091 struct rpc_xprt * 1092 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1093 { 1094 struct rpc_xprt_switch *xps; 1095 1096 if (!xprt) 1097 return NULL; 1098 rcu_read_lock(); 1099 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1100 atomic_long_inc(&xps->xps_queuelen); 1101 rcu_read_unlock(); 1102 atomic_long_inc(&xprt->queuelen); 1103 1104 return xprt; 1105 } 1106 1107 static void 1108 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1109 { 1110 struct rpc_xprt_switch *xps; 1111 1112 atomic_long_dec(&xprt->queuelen); 1113 rcu_read_lock(); 1114 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1115 atomic_long_dec(&xps->xps_queuelen); 1116 rcu_read_unlock(); 1117 1118 xprt_put(xprt); 1119 } 1120 1121 void rpc_task_release_transport(struct rpc_task *task) 1122 { 1123 struct rpc_xprt *xprt = task->tk_xprt; 1124 1125 if (xprt) { 1126 task->tk_xprt = NULL; 1127 if (task->tk_client) 1128 rpc_task_release_xprt(task->tk_client, xprt); 1129 else 1130 xprt_put(xprt); 1131 } 1132 } 1133 EXPORT_SYMBOL_GPL(rpc_task_release_transport); 1134 1135 void rpc_task_release_client(struct rpc_task *task) 1136 { 1137 struct rpc_clnt *clnt = task->tk_client; 1138 1139 rpc_task_release_transport(task); 1140 if (clnt != NULL) { 1141 /* Remove from client task list */ 1142 spin_lock(&clnt->cl_lock); 1143 list_del(&task->tk_task); 1144 spin_unlock(&clnt->cl_lock); 1145 task->tk_client = NULL; 1146 1147 rpc_release_client(clnt); 1148 } 1149 } 1150 1151 static struct rpc_xprt * 1152 rpc_task_get_first_xprt(struct rpc_clnt *clnt) 1153 { 1154 struct rpc_xprt *xprt; 1155 1156 rcu_read_lock(); 1157 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 1158 rcu_read_unlock(); 1159 return rpc_task_get_xprt(clnt, xprt); 1160 } 1161 1162 static struct rpc_xprt * 1163 rpc_task_get_next_xprt(struct rpc_clnt *clnt) 1164 { 1165 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi)); 1166 } 1167 1168 static 1169 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) 1170 { 1171 if (task->tk_xprt) { 1172 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) && 1173 (task->tk_flags & RPC_TASK_MOVEABLE))) 1174 return; 1175 xprt_release(task); 1176 xprt_put(task->tk_xprt); 1177 } 1178 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) 1179 task->tk_xprt = rpc_task_get_first_xprt(clnt); 1180 else 1181 task->tk_xprt = rpc_task_get_next_xprt(clnt); 1182 } 1183 1184 static 1185 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 1186 { 1187 rpc_task_set_transport(task, clnt); 1188 task->tk_client = clnt; 1189 refcount_inc(&clnt->cl_count); 1190 if (clnt->cl_softrtry) 1191 task->tk_flags |= RPC_TASK_SOFT; 1192 if (clnt->cl_softerr) 1193 task->tk_flags |= RPC_TASK_TIMEOUT; 1194 if (clnt->cl_noretranstimeo) 1195 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1196 /* Add to the client's list of all tasks */ 1197 spin_lock(&clnt->cl_lock); 1198 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1199 spin_unlock(&clnt->cl_lock); 1200 } 1201 1202 static void 1203 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1204 { 1205 if (msg != NULL) { 1206 task->tk_msg.rpc_proc = msg->rpc_proc; 1207 task->tk_msg.rpc_argp = msg->rpc_argp; 1208 task->tk_msg.rpc_resp = msg->rpc_resp; 1209 task->tk_msg.rpc_cred = msg->rpc_cred; 1210 if (!(task->tk_flags & RPC_TASK_CRED_NOREF)) 1211 get_cred(task->tk_msg.rpc_cred); 1212 } 1213 } 1214 1215 /* 1216 * Default callback for async RPC calls 1217 */ 1218 static void 1219 rpc_default_callback(struct rpc_task *task, void *data) 1220 { 1221 } 1222 1223 static const struct rpc_call_ops rpc_default_ops = { 1224 .rpc_call_done = rpc_default_callback, 1225 }; 1226 1227 /** 1228 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1229 * @task_setup_data: pointer to task initialisation data 1230 */ 1231 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1232 { 1233 struct rpc_task *task; 1234 1235 task = rpc_new_task(task_setup_data); 1236 if (IS_ERR(task)) 1237 return task; 1238 1239 if (!RPC_IS_ASYNC(task)) 1240 task->tk_flags |= RPC_TASK_CRED_NOREF; 1241 1242 rpc_task_set_client(task, task_setup_data->rpc_client); 1243 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1244 1245 if (task->tk_action == NULL) 1246 rpc_call_start(task); 1247 1248 atomic_inc(&task->tk_count); 1249 rpc_execute(task); 1250 return task; 1251 } 1252 EXPORT_SYMBOL_GPL(rpc_run_task); 1253 1254 /** 1255 * rpc_call_sync - Perform a synchronous RPC call 1256 * @clnt: pointer to RPC client 1257 * @msg: RPC call parameters 1258 * @flags: RPC call flags 1259 */ 1260 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1261 { 1262 struct rpc_task *task; 1263 struct rpc_task_setup task_setup_data = { 1264 .rpc_client = clnt, 1265 .rpc_message = msg, 1266 .callback_ops = &rpc_default_ops, 1267 .flags = flags, 1268 }; 1269 int status; 1270 1271 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1272 if (flags & RPC_TASK_ASYNC) { 1273 rpc_release_calldata(task_setup_data.callback_ops, 1274 task_setup_data.callback_data); 1275 return -EINVAL; 1276 } 1277 1278 task = rpc_run_task(&task_setup_data); 1279 if (IS_ERR(task)) 1280 return PTR_ERR(task); 1281 status = task->tk_status; 1282 rpc_put_task(task); 1283 return status; 1284 } 1285 EXPORT_SYMBOL_GPL(rpc_call_sync); 1286 1287 /** 1288 * rpc_call_async - Perform an asynchronous RPC call 1289 * @clnt: pointer to RPC client 1290 * @msg: RPC call parameters 1291 * @flags: RPC call flags 1292 * @tk_ops: RPC call ops 1293 * @data: user call data 1294 */ 1295 int 1296 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1297 const struct rpc_call_ops *tk_ops, void *data) 1298 { 1299 struct rpc_task *task; 1300 struct rpc_task_setup task_setup_data = { 1301 .rpc_client = clnt, 1302 .rpc_message = msg, 1303 .callback_ops = tk_ops, 1304 .callback_data = data, 1305 .flags = flags|RPC_TASK_ASYNC, 1306 }; 1307 1308 task = rpc_run_task(&task_setup_data); 1309 if (IS_ERR(task)) 1310 return PTR_ERR(task); 1311 rpc_put_task(task); 1312 return 0; 1313 } 1314 EXPORT_SYMBOL_GPL(rpc_call_async); 1315 1316 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1317 static void call_bc_encode(struct rpc_task *task); 1318 1319 /** 1320 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1321 * rpc_execute against it 1322 * @req: RPC request 1323 * @timeout: timeout values to use for this task 1324 */ 1325 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req, 1326 struct rpc_timeout *timeout) 1327 { 1328 struct rpc_task *task; 1329 struct rpc_task_setup task_setup_data = { 1330 .callback_ops = &rpc_default_ops, 1331 .flags = RPC_TASK_SOFTCONN | 1332 RPC_TASK_NO_RETRANS_TIMEOUT, 1333 }; 1334 1335 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1336 /* 1337 * Create an rpc_task to send the data 1338 */ 1339 task = rpc_new_task(&task_setup_data); 1340 if (IS_ERR(task)) { 1341 xprt_free_bc_request(req); 1342 return task; 1343 } 1344 1345 xprt_init_bc_request(req, task, timeout); 1346 1347 task->tk_action = call_bc_encode; 1348 atomic_inc(&task->tk_count); 1349 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1350 rpc_execute(task); 1351 1352 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1353 return task; 1354 } 1355 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1356 1357 /** 1358 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages 1359 * @req: RPC request to prepare 1360 * @pages: vector of struct page pointers 1361 * @base: offset in first page where receive should start, in bytes 1362 * @len: expected size of the upper layer data payload, in bytes 1363 * @hdrsize: expected size of upper layer reply header, in XDR words 1364 * 1365 */ 1366 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, 1367 unsigned int base, unsigned int len, 1368 unsigned int hdrsize) 1369 { 1370 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; 1371 1372 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); 1373 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); 1374 } 1375 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages); 1376 1377 void 1378 rpc_call_start(struct rpc_task *task) 1379 { 1380 task->tk_action = call_start; 1381 } 1382 EXPORT_SYMBOL_GPL(rpc_call_start); 1383 1384 /** 1385 * rpc_peeraddr - extract remote peer address from clnt's xprt 1386 * @clnt: RPC client structure 1387 * @buf: target buffer 1388 * @bufsize: length of target buffer 1389 * 1390 * Returns the number of bytes that are actually in the stored address. 1391 */ 1392 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1393 { 1394 size_t bytes; 1395 struct rpc_xprt *xprt; 1396 1397 rcu_read_lock(); 1398 xprt = rcu_dereference(clnt->cl_xprt); 1399 1400 bytes = xprt->addrlen; 1401 if (bytes > bufsize) 1402 bytes = bufsize; 1403 memcpy(buf, &xprt->addr, bytes); 1404 rcu_read_unlock(); 1405 1406 return bytes; 1407 } 1408 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1409 1410 /** 1411 * rpc_peeraddr2str - return remote peer address in printable format 1412 * @clnt: RPC client structure 1413 * @format: address format 1414 * 1415 * NB: the lifetime of the memory referenced by the returned pointer is 1416 * the same as the rpc_xprt itself. As long as the caller uses this 1417 * pointer, it must hold the RCU read lock. 1418 */ 1419 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1420 enum rpc_display_format_t format) 1421 { 1422 struct rpc_xprt *xprt; 1423 1424 xprt = rcu_dereference(clnt->cl_xprt); 1425 1426 if (xprt->address_strings[format] != NULL) 1427 return xprt->address_strings[format]; 1428 else 1429 return "unprintable"; 1430 } 1431 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1432 1433 static const struct sockaddr_in rpc_inaddr_loopback = { 1434 .sin_family = AF_INET, 1435 .sin_addr.s_addr = htonl(INADDR_ANY), 1436 }; 1437 1438 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1439 .sin6_family = AF_INET6, 1440 .sin6_addr = IN6ADDR_ANY_INIT, 1441 }; 1442 1443 /* 1444 * Try a getsockname() on a connected datagram socket. Using a 1445 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1446 * This conserves the ephemeral port number space. 1447 * 1448 * Returns zero and fills in "buf" if successful; otherwise, a 1449 * negative errno is returned. 1450 */ 1451 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1452 struct sockaddr *buf) 1453 { 1454 struct socket *sock; 1455 int err; 1456 1457 err = __sock_create(net, sap->sa_family, 1458 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1459 if (err < 0) { 1460 dprintk("RPC: can't create UDP socket (%d)\n", err); 1461 goto out; 1462 } 1463 1464 switch (sap->sa_family) { 1465 case AF_INET: 1466 err = kernel_bind(sock, 1467 (struct sockaddr *)&rpc_inaddr_loopback, 1468 sizeof(rpc_inaddr_loopback)); 1469 break; 1470 case AF_INET6: 1471 err = kernel_bind(sock, 1472 (struct sockaddr *)&rpc_in6addr_loopback, 1473 sizeof(rpc_in6addr_loopback)); 1474 break; 1475 default: 1476 err = -EAFNOSUPPORT; 1477 goto out_release; 1478 } 1479 if (err < 0) { 1480 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1481 goto out_release; 1482 } 1483 1484 err = kernel_connect(sock, sap, salen, 0); 1485 if (err < 0) { 1486 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1487 goto out_release; 1488 } 1489 1490 err = kernel_getsockname(sock, buf); 1491 if (err < 0) { 1492 dprintk("RPC: getsockname failed (%d)\n", err); 1493 goto out_release; 1494 } 1495 1496 err = 0; 1497 if (buf->sa_family == AF_INET6) { 1498 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1499 sin6->sin6_scope_id = 0; 1500 } 1501 dprintk("RPC: %s succeeded\n", __func__); 1502 1503 out_release: 1504 sock_release(sock); 1505 out: 1506 return err; 1507 } 1508 1509 /* 1510 * Scraping a connected socket failed, so we don't have a useable 1511 * local address. Fallback: generate an address that will prevent 1512 * the server from calling us back. 1513 * 1514 * Returns zero and fills in "buf" if successful; otherwise, a 1515 * negative errno is returned. 1516 */ 1517 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1518 { 1519 switch (family) { 1520 case AF_INET: 1521 if (buflen < sizeof(rpc_inaddr_loopback)) 1522 return -EINVAL; 1523 memcpy(buf, &rpc_inaddr_loopback, 1524 sizeof(rpc_inaddr_loopback)); 1525 break; 1526 case AF_INET6: 1527 if (buflen < sizeof(rpc_in6addr_loopback)) 1528 return -EINVAL; 1529 memcpy(buf, &rpc_in6addr_loopback, 1530 sizeof(rpc_in6addr_loopback)); 1531 break; 1532 default: 1533 dprintk("RPC: %s: address family not supported\n", 1534 __func__); 1535 return -EAFNOSUPPORT; 1536 } 1537 dprintk("RPC: %s: succeeded\n", __func__); 1538 return 0; 1539 } 1540 1541 /** 1542 * rpc_localaddr - discover local endpoint address for an RPC client 1543 * @clnt: RPC client structure 1544 * @buf: target buffer 1545 * @buflen: size of target buffer, in bytes 1546 * 1547 * Returns zero and fills in "buf" and "buflen" if successful; 1548 * otherwise, a negative errno is returned. 1549 * 1550 * This works even if the underlying transport is not currently connected, 1551 * or if the upper layer never previously provided a source address. 1552 * 1553 * The result of this function call is transient: multiple calls in 1554 * succession may give different results, depending on how local 1555 * networking configuration changes over time. 1556 */ 1557 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1558 { 1559 struct sockaddr_storage address; 1560 struct sockaddr *sap = (struct sockaddr *)&address; 1561 struct rpc_xprt *xprt; 1562 struct net *net; 1563 size_t salen; 1564 int err; 1565 1566 rcu_read_lock(); 1567 xprt = rcu_dereference(clnt->cl_xprt); 1568 salen = xprt->addrlen; 1569 memcpy(sap, &xprt->addr, salen); 1570 net = get_net(xprt->xprt_net); 1571 rcu_read_unlock(); 1572 1573 rpc_set_port(sap, 0); 1574 err = rpc_sockname(net, sap, salen, buf); 1575 put_net(net); 1576 if (err != 0) 1577 /* Couldn't discover local address, return ANYADDR */ 1578 return rpc_anyaddr(sap->sa_family, buf, buflen); 1579 return 0; 1580 } 1581 EXPORT_SYMBOL_GPL(rpc_localaddr); 1582 1583 void 1584 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1585 { 1586 struct rpc_xprt *xprt; 1587 1588 rcu_read_lock(); 1589 xprt = rcu_dereference(clnt->cl_xprt); 1590 if (xprt->ops->set_buffer_size) 1591 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1592 rcu_read_unlock(); 1593 } 1594 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1595 1596 /** 1597 * rpc_net_ns - Get the network namespace for this RPC client 1598 * @clnt: RPC client to query 1599 * 1600 */ 1601 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1602 { 1603 struct net *ret; 1604 1605 rcu_read_lock(); 1606 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1607 rcu_read_unlock(); 1608 return ret; 1609 } 1610 EXPORT_SYMBOL_GPL(rpc_net_ns); 1611 1612 /** 1613 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1614 * @clnt: RPC client to query 1615 * 1616 * For stream transports, this is one RPC record fragment (see RFC 1617 * 1831), as we don't support multi-record requests yet. For datagram 1618 * transports, this is the size of an IP packet minus the IP, UDP, and 1619 * RPC header sizes. 1620 */ 1621 size_t rpc_max_payload(struct rpc_clnt *clnt) 1622 { 1623 size_t ret; 1624 1625 rcu_read_lock(); 1626 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1627 rcu_read_unlock(); 1628 return ret; 1629 } 1630 EXPORT_SYMBOL_GPL(rpc_max_payload); 1631 1632 /** 1633 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1634 * @clnt: RPC client to query 1635 */ 1636 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1637 { 1638 struct rpc_xprt *xprt; 1639 size_t ret; 1640 1641 rcu_read_lock(); 1642 xprt = rcu_dereference(clnt->cl_xprt); 1643 ret = xprt->ops->bc_maxpayload(xprt); 1644 rcu_read_unlock(); 1645 return ret; 1646 } 1647 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1648 1649 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt) 1650 { 1651 struct rpc_xprt *xprt; 1652 unsigned int ret; 1653 1654 rcu_read_lock(); 1655 xprt = rcu_dereference(clnt->cl_xprt); 1656 ret = xprt->ops->bc_num_slots(xprt); 1657 rcu_read_unlock(); 1658 return ret; 1659 } 1660 EXPORT_SYMBOL_GPL(rpc_num_bc_slots); 1661 1662 /** 1663 * rpc_force_rebind - force transport to check that remote port is unchanged 1664 * @clnt: client to rebind 1665 * 1666 */ 1667 void rpc_force_rebind(struct rpc_clnt *clnt) 1668 { 1669 if (clnt->cl_autobind) { 1670 rcu_read_lock(); 1671 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1672 rcu_read_unlock(); 1673 } 1674 } 1675 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1676 1677 static int 1678 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *)) 1679 { 1680 task->tk_status = 0; 1681 task->tk_rpc_status = 0; 1682 task->tk_action = action; 1683 return 1; 1684 } 1685 1686 /* 1687 * Restart an (async) RPC call. Usually called from within the 1688 * exit handler. 1689 */ 1690 int 1691 rpc_restart_call(struct rpc_task *task) 1692 { 1693 return __rpc_restart_call(task, call_start); 1694 } 1695 EXPORT_SYMBOL_GPL(rpc_restart_call); 1696 1697 /* 1698 * Restart an (async) RPC call from the call_prepare state. 1699 * Usually called from within the exit handler. 1700 */ 1701 int 1702 rpc_restart_call_prepare(struct rpc_task *task) 1703 { 1704 if (task->tk_ops->rpc_call_prepare != NULL) 1705 return __rpc_restart_call(task, rpc_prepare_task); 1706 return rpc_restart_call(task); 1707 } 1708 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1709 1710 const char 1711 *rpc_proc_name(const struct rpc_task *task) 1712 { 1713 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1714 1715 if (proc) { 1716 if (proc->p_name) 1717 return proc->p_name; 1718 else 1719 return "NULL"; 1720 } else 1721 return "no proc"; 1722 } 1723 1724 static void 1725 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status) 1726 { 1727 trace_rpc_call_rpcerror(task, tk_status, rpc_status); 1728 rpc_task_set_rpc_status(task, rpc_status); 1729 rpc_exit(task, tk_status); 1730 } 1731 1732 static void 1733 rpc_call_rpcerror(struct rpc_task *task, int status) 1734 { 1735 __rpc_call_rpcerror(task, status, status); 1736 } 1737 1738 /* 1739 * 0. Initial state 1740 * 1741 * Other FSM states can be visited zero or more times, but 1742 * this state is visited exactly once for each RPC. 1743 */ 1744 static void 1745 call_start(struct rpc_task *task) 1746 { 1747 struct rpc_clnt *clnt = task->tk_client; 1748 int idx = task->tk_msg.rpc_proc->p_statidx; 1749 1750 trace_rpc_request(task); 1751 1752 if (task->tk_client->cl_shutdown) { 1753 rpc_call_rpcerror(task, -EIO); 1754 return; 1755 } 1756 1757 /* Increment call count (version might not be valid for ping) */ 1758 if (clnt->cl_program->version[clnt->cl_vers]) 1759 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; 1760 clnt->cl_stats->rpccnt++; 1761 task->tk_action = call_reserve; 1762 rpc_task_set_transport(task, clnt); 1763 } 1764 1765 /* 1766 * 1. Reserve an RPC call slot 1767 */ 1768 static void 1769 call_reserve(struct rpc_task *task) 1770 { 1771 task->tk_status = 0; 1772 task->tk_action = call_reserveresult; 1773 xprt_reserve(task); 1774 } 1775 1776 static void call_retry_reserve(struct rpc_task *task); 1777 1778 /* 1779 * 1b. Grok the result of xprt_reserve() 1780 */ 1781 static void 1782 call_reserveresult(struct rpc_task *task) 1783 { 1784 int status = task->tk_status; 1785 1786 /* 1787 * After a call to xprt_reserve(), we must have either 1788 * a request slot or else an error status. 1789 */ 1790 task->tk_status = 0; 1791 if (status >= 0) { 1792 if (task->tk_rqstp) { 1793 task->tk_action = call_refresh; 1794 return; 1795 } 1796 1797 rpc_call_rpcerror(task, -EIO); 1798 return; 1799 } 1800 1801 switch (status) { 1802 case -ENOMEM: 1803 rpc_delay(task, HZ >> 2); 1804 fallthrough; 1805 case -EAGAIN: /* woken up; retry */ 1806 task->tk_action = call_retry_reserve; 1807 return; 1808 default: 1809 rpc_call_rpcerror(task, status); 1810 } 1811 } 1812 1813 /* 1814 * 1c. Retry reserving an RPC call slot 1815 */ 1816 static void 1817 call_retry_reserve(struct rpc_task *task) 1818 { 1819 task->tk_status = 0; 1820 task->tk_action = call_reserveresult; 1821 xprt_retry_reserve(task); 1822 } 1823 1824 /* 1825 * 2. Bind and/or refresh the credentials 1826 */ 1827 static void 1828 call_refresh(struct rpc_task *task) 1829 { 1830 task->tk_action = call_refreshresult; 1831 task->tk_status = 0; 1832 task->tk_client->cl_stats->rpcauthrefresh++; 1833 rpcauth_refreshcred(task); 1834 } 1835 1836 /* 1837 * 2a. Process the results of a credential refresh 1838 */ 1839 static void 1840 call_refreshresult(struct rpc_task *task) 1841 { 1842 int status = task->tk_status; 1843 1844 task->tk_status = 0; 1845 task->tk_action = call_refresh; 1846 switch (status) { 1847 case 0: 1848 if (rpcauth_uptodatecred(task)) { 1849 task->tk_action = call_allocate; 1850 return; 1851 } 1852 /* Use rate-limiting and a max number of retries if refresh 1853 * had status 0 but failed to update the cred. 1854 */ 1855 fallthrough; 1856 case -ETIMEDOUT: 1857 rpc_delay(task, 3*HZ); 1858 fallthrough; 1859 case -EAGAIN: 1860 status = -EACCES; 1861 fallthrough; 1862 case -EKEYEXPIRED: 1863 if (!task->tk_cred_retry) 1864 break; 1865 task->tk_cred_retry--; 1866 trace_rpc_retry_refresh_status(task); 1867 return; 1868 case -ENOMEM: 1869 rpc_delay(task, HZ >> 4); 1870 return; 1871 } 1872 trace_rpc_refresh_status(task); 1873 rpc_call_rpcerror(task, status); 1874 } 1875 1876 /* 1877 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1878 * (Note: buffer memory is freed in xprt_release). 1879 */ 1880 static void 1881 call_allocate(struct rpc_task *task) 1882 { 1883 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth; 1884 struct rpc_rqst *req = task->tk_rqstp; 1885 struct rpc_xprt *xprt = req->rq_xprt; 1886 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1887 int status; 1888 1889 task->tk_status = 0; 1890 task->tk_action = call_encode; 1891 1892 if (req->rq_buffer) 1893 return; 1894 1895 if (proc->p_proc != 0) { 1896 BUG_ON(proc->p_arglen == 0); 1897 if (proc->p_decode != NULL) 1898 BUG_ON(proc->p_replen == 0); 1899 } 1900 1901 /* 1902 * Calculate the size (in quads) of the RPC call 1903 * and reply headers, and convert both values 1904 * to byte sizes. 1905 */ 1906 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + 1907 proc->p_arglen; 1908 req->rq_callsize <<= 2; 1909 /* 1910 * Note: the reply buffer must at minimum allocate enough space 1911 * for the 'struct accepted_reply' from RFC5531. 1912 */ 1913 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ 1914 max_t(size_t, proc->p_replen, 2); 1915 req->rq_rcvsize <<= 2; 1916 1917 status = xprt->ops->buf_alloc(task); 1918 trace_rpc_buf_alloc(task, status); 1919 if (status == 0) 1920 return; 1921 if (status != -ENOMEM) { 1922 rpc_call_rpcerror(task, status); 1923 return; 1924 } 1925 1926 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1927 task->tk_action = call_allocate; 1928 rpc_delay(task, HZ>>4); 1929 return; 1930 } 1931 1932 rpc_call_rpcerror(task, -ERESTARTSYS); 1933 } 1934 1935 static int 1936 rpc_task_need_encode(struct rpc_task *task) 1937 { 1938 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 && 1939 (!(task->tk_flags & RPC_TASK_SENT) || 1940 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) || 1941 xprt_request_need_retransmit(task)); 1942 } 1943 1944 static void 1945 rpc_xdr_encode(struct rpc_task *task) 1946 { 1947 struct rpc_rqst *req = task->tk_rqstp; 1948 struct xdr_stream xdr; 1949 1950 xdr_buf_init(&req->rq_snd_buf, 1951 req->rq_buffer, 1952 req->rq_callsize); 1953 xdr_buf_init(&req->rq_rcv_buf, 1954 req->rq_rbuffer, 1955 req->rq_rcvsize); 1956 1957 req->rq_reply_bytes_recvd = 0; 1958 req->rq_snd_buf.head[0].iov_len = 0; 1959 xdr_init_encode(&xdr, &req->rq_snd_buf, 1960 req->rq_snd_buf.head[0].iov_base, req); 1961 if (rpc_encode_header(task, &xdr)) 1962 return; 1963 1964 task->tk_status = rpcauth_wrap_req(task, &xdr); 1965 } 1966 1967 /* 1968 * 3. Encode arguments of an RPC call 1969 */ 1970 static void 1971 call_encode(struct rpc_task *task) 1972 { 1973 if (!rpc_task_need_encode(task)) 1974 goto out; 1975 1976 /* Dequeue task from the receive queue while we're encoding */ 1977 xprt_request_dequeue_xprt(task); 1978 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1979 rpc_xdr_encode(task); 1980 /* Add task to reply queue before transmission to avoid races */ 1981 if (task->tk_status == 0 && rpc_reply_expected(task)) 1982 task->tk_status = xprt_request_enqueue_receive(task); 1983 /* Did the encode result in an error condition? */ 1984 if (task->tk_status != 0) { 1985 /* Was the error nonfatal? */ 1986 switch (task->tk_status) { 1987 case -EAGAIN: 1988 case -ENOMEM: 1989 rpc_delay(task, HZ >> 4); 1990 break; 1991 case -EKEYEXPIRED: 1992 if (!task->tk_cred_retry) { 1993 rpc_call_rpcerror(task, task->tk_status); 1994 } else { 1995 task->tk_action = call_refresh; 1996 task->tk_cred_retry--; 1997 trace_rpc_retry_refresh_status(task); 1998 } 1999 break; 2000 default: 2001 rpc_call_rpcerror(task, task->tk_status); 2002 } 2003 return; 2004 } 2005 2006 xprt_request_enqueue_transmit(task); 2007 out: 2008 task->tk_action = call_transmit; 2009 /* Check that the connection is OK */ 2010 if (!xprt_bound(task->tk_xprt)) 2011 task->tk_action = call_bind; 2012 else if (!xprt_connected(task->tk_xprt)) 2013 task->tk_action = call_connect; 2014 } 2015 2016 /* 2017 * Helpers to check if the task was already transmitted, and 2018 * to take action when that is the case. 2019 */ 2020 static bool 2021 rpc_task_transmitted(struct rpc_task *task) 2022 { 2023 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 2024 } 2025 2026 static void 2027 rpc_task_handle_transmitted(struct rpc_task *task) 2028 { 2029 xprt_end_transmit(task); 2030 task->tk_action = call_transmit_status; 2031 } 2032 2033 /* 2034 * 4. Get the server port number if not yet set 2035 */ 2036 static void 2037 call_bind(struct rpc_task *task) 2038 { 2039 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2040 2041 if (rpc_task_transmitted(task)) { 2042 rpc_task_handle_transmitted(task); 2043 return; 2044 } 2045 2046 if (xprt_bound(xprt)) { 2047 task->tk_action = call_connect; 2048 return; 2049 } 2050 2051 task->tk_action = call_bind_status; 2052 if (!xprt_prepare_transmit(task)) 2053 return; 2054 2055 xprt->ops->rpcbind(task); 2056 } 2057 2058 /* 2059 * 4a. Sort out bind result 2060 */ 2061 static void 2062 call_bind_status(struct rpc_task *task) 2063 { 2064 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2065 int status = -EIO; 2066 2067 if (rpc_task_transmitted(task)) { 2068 rpc_task_handle_transmitted(task); 2069 return; 2070 } 2071 2072 if (task->tk_status >= 0) 2073 goto out_next; 2074 if (xprt_bound(xprt)) { 2075 task->tk_status = 0; 2076 goto out_next; 2077 } 2078 2079 switch (task->tk_status) { 2080 case -ENOMEM: 2081 rpc_delay(task, HZ >> 2); 2082 goto retry_timeout; 2083 case -EACCES: 2084 trace_rpcb_prog_unavail_err(task); 2085 /* fail immediately if this is an RPC ping */ 2086 if (task->tk_msg.rpc_proc->p_proc == 0) { 2087 status = -EOPNOTSUPP; 2088 break; 2089 } 2090 rpc_delay(task, 3*HZ); 2091 goto retry_timeout; 2092 case -ENOBUFS: 2093 rpc_delay(task, HZ >> 2); 2094 goto retry_timeout; 2095 case -EAGAIN: 2096 goto retry_timeout; 2097 case -ETIMEDOUT: 2098 trace_rpcb_timeout_err(task); 2099 goto retry_timeout; 2100 case -EPFNOSUPPORT: 2101 /* server doesn't support any rpcbind version we know of */ 2102 trace_rpcb_bind_version_err(task); 2103 break; 2104 case -EPROTONOSUPPORT: 2105 trace_rpcb_bind_version_err(task); 2106 goto retry_timeout; 2107 case -ECONNREFUSED: /* connection problems */ 2108 case -ECONNRESET: 2109 case -ECONNABORTED: 2110 case -ENOTCONN: 2111 case -EHOSTDOWN: 2112 case -ENETDOWN: 2113 case -EHOSTUNREACH: 2114 case -ENETUNREACH: 2115 case -EPIPE: 2116 trace_rpcb_unreachable_err(task); 2117 if (!RPC_IS_SOFTCONN(task)) { 2118 rpc_delay(task, 5*HZ); 2119 goto retry_timeout; 2120 } 2121 status = task->tk_status; 2122 break; 2123 default: 2124 trace_rpcb_unrecognized_err(task); 2125 } 2126 2127 rpc_call_rpcerror(task, status); 2128 return; 2129 out_next: 2130 task->tk_action = call_connect; 2131 return; 2132 retry_timeout: 2133 task->tk_status = 0; 2134 task->tk_action = call_bind; 2135 rpc_check_timeout(task); 2136 } 2137 2138 /* 2139 * 4b. Connect to the RPC server 2140 */ 2141 static void 2142 call_connect(struct rpc_task *task) 2143 { 2144 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2145 2146 if (rpc_task_transmitted(task)) { 2147 rpc_task_handle_transmitted(task); 2148 return; 2149 } 2150 2151 if (xprt_connected(xprt)) { 2152 task->tk_action = call_transmit; 2153 return; 2154 } 2155 2156 task->tk_action = call_connect_status; 2157 if (task->tk_status < 0) 2158 return; 2159 if (task->tk_flags & RPC_TASK_NOCONNECT) { 2160 rpc_call_rpcerror(task, -ENOTCONN); 2161 return; 2162 } 2163 if (!xprt_prepare_transmit(task)) 2164 return; 2165 xprt_connect(task); 2166 } 2167 2168 /* 2169 * 4c. Sort out connect result 2170 */ 2171 static void 2172 call_connect_status(struct rpc_task *task) 2173 { 2174 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2175 struct rpc_clnt *clnt = task->tk_client; 2176 int status = task->tk_status; 2177 2178 if (rpc_task_transmitted(task)) { 2179 rpc_task_handle_transmitted(task); 2180 return; 2181 } 2182 2183 trace_rpc_connect_status(task); 2184 2185 if (task->tk_status == 0) { 2186 clnt->cl_stats->netreconn++; 2187 goto out_next; 2188 } 2189 if (xprt_connected(xprt)) { 2190 task->tk_status = 0; 2191 goto out_next; 2192 } 2193 2194 task->tk_status = 0; 2195 switch (status) { 2196 case -ECONNREFUSED: 2197 case -ECONNRESET: 2198 /* A positive refusal suggests a rebind is needed. */ 2199 if (RPC_IS_SOFTCONN(task)) 2200 break; 2201 if (clnt->cl_autobind) { 2202 rpc_force_rebind(clnt); 2203 goto out_retry; 2204 } 2205 fallthrough; 2206 case -ECONNABORTED: 2207 case -ENETDOWN: 2208 case -ENETUNREACH: 2209 case -EHOSTUNREACH: 2210 case -EPIPE: 2211 case -EPROTO: 2212 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, 2213 task->tk_rqstp->rq_connect_cookie); 2214 if (RPC_IS_SOFTCONN(task)) 2215 break; 2216 /* retry with existing socket, after a delay */ 2217 rpc_delay(task, 3*HZ); 2218 fallthrough; 2219 case -EADDRINUSE: 2220 case -ENOTCONN: 2221 case -EAGAIN: 2222 case -ETIMEDOUT: 2223 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) && 2224 (task->tk_flags & RPC_TASK_MOVEABLE) && 2225 test_bit(XPRT_REMOVE, &xprt->state)) { 2226 struct rpc_xprt *saved = task->tk_xprt; 2227 struct rpc_xprt_switch *xps; 2228 2229 xps = rpc_clnt_xprt_switch_get(clnt); 2230 if (xps->xps_nxprts > 1) { 2231 long value; 2232 2233 xprt_release(task); 2234 value = atomic_long_dec_return(&xprt->queuelen); 2235 if (value == 0) 2236 rpc_xprt_switch_remove_xprt(xps, saved, 2237 true); 2238 xprt_put(saved); 2239 task->tk_xprt = NULL; 2240 task->tk_action = call_start; 2241 } 2242 xprt_switch_put(xps); 2243 if (!task->tk_xprt) 2244 goto out; 2245 } 2246 goto out_retry; 2247 case -ENOBUFS: 2248 rpc_delay(task, HZ >> 2); 2249 goto out_retry; 2250 } 2251 rpc_call_rpcerror(task, status); 2252 return; 2253 out_next: 2254 task->tk_action = call_transmit; 2255 return; 2256 out_retry: 2257 /* Check for timeouts before looping back to call_bind */ 2258 task->tk_action = call_bind; 2259 out: 2260 rpc_check_timeout(task); 2261 } 2262 2263 /* 2264 * 5. Transmit the RPC request, and wait for reply 2265 */ 2266 static void 2267 call_transmit(struct rpc_task *task) 2268 { 2269 if (rpc_task_transmitted(task)) { 2270 rpc_task_handle_transmitted(task); 2271 return; 2272 } 2273 2274 task->tk_action = call_transmit_status; 2275 if (!xprt_prepare_transmit(task)) 2276 return; 2277 task->tk_status = 0; 2278 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2279 if (!xprt_connected(task->tk_xprt)) { 2280 task->tk_status = -ENOTCONN; 2281 return; 2282 } 2283 xprt_transmit(task); 2284 } 2285 xprt_end_transmit(task); 2286 } 2287 2288 /* 2289 * 5a. Handle cleanup after a transmission 2290 */ 2291 static void 2292 call_transmit_status(struct rpc_task *task) 2293 { 2294 task->tk_action = call_status; 2295 2296 /* 2297 * Common case: success. Force the compiler to put this 2298 * test first. 2299 */ 2300 if (rpc_task_transmitted(task)) { 2301 task->tk_status = 0; 2302 xprt_request_wait_receive(task); 2303 return; 2304 } 2305 2306 switch (task->tk_status) { 2307 default: 2308 break; 2309 case -EBADMSG: 2310 task->tk_status = 0; 2311 task->tk_action = call_encode; 2312 break; 2313 /* 2314 * Special cases: if we've been waiting on the 2315 * socket's write_space() callback, or if the 2316 * socket just returned a connection error, 2317 * then hold onto the transport lock. 2318 */ 2319 case -ENOMEM: 2320 case -ENOBUFS: 2321 rpc_delay(task, HZ>>2); 2322 fallthrough; 2323 case -EBADSLT: 2324 case -EAGAIN: 2325 task->tk_action = call_transmit; 2326 task->tk_status = 0; 2327 break; 2328 case -ECONNREFUSED: 2329 case -EHOSTDOWN: 2330 case -ENETDOWN: 2331 case -EHOSTUNREACH: 2332 case -ENETUNREACH: 2333 case -EPERM: 2334 if (RPC_IS_SOFTCONN(task)) { 2335 if (!task->tk_msg.rpc_proc->p_proc) 2336 trace_xprt_ping(task->tk_xprt, 2337 task->tk_status); 2338 rpc_call_rpcerror(task, task->tk_status); 2339 return; 2340 } 2341 fallthrough; 2342 case -ECONNRESET: 2343 case -ECONNABORTED: 2344 case -EADDRINUSE: 2345 case -ENOTCONN: 2346 case -EPIPE: 2347 task->tk_action = call_bind; 2348 task->tk_status = 0; 2349 break; 2350 } 2351 rpc_check_timeout(task); 2352 } 2353 2354 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2355 static void call_bc_transmit(struct rpc_task *task); 2356 static void call_bc_transmit_status(struct rpc_task *task); 2357 2358 static void 2359 call_bc_encode(struct rpc_task *task) 2360 { 2361 xprt_request_enqueue_transmit(task); 2362 task->tk_action = call_bc_transmit; 2363 } 2364 2365 /* 2366 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2367 * addition, disconnect on connectivity errors. 2368 */ 2369 static void 2370 call_bc_transmit(struct rpc_task *task) 2371 { 2372 task->tk_action = call_bc_transmit_status; 2373 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2374 if (!xprt_prepare_transmit(task)) 2375 return; 2376 task->tk_status = 0; 2377 xprt_transmit(task); 2378 } 2379 xprt_end_transmit(task); 2380 } 2381 2382 static void 2383 call_bc_transmit_status(struct rpc_task *task) 2384 { 2385 struct rpc_rqst *req = task->tk_rqstp; 2386 2387 if (rpc_task_transmitted(task)) 2388 task->tk_status = 0; 2389 2390 switch (task->tk_status) { 2391 case 0: 2392 /* Success */ 2393 case -ENETDOWN: 2394 case -EHOSTDOWN: 2395 case -EHOSTUNREACH: 2396 case -ENETUNREACH: 2397 case -ECONNRESET: 2398 case -ECONNREFUSED: 2399 case -EADDRINUSE: 2400 case -ENOTCONN: 2401 case -EPIPE: 2402 break; 2403 case -ENOMEM: 2404 case -ENOBUFS: 2405 rpc_delay(task, HZ>>2); 2406 fallthrough; 2407 case -EBADSLT: 2408 case -EAGAIN: 2409 task->tk_status = 0; 2410 task->tk_action = call_bc_transmit; 2411 return; 2412 case -ETIMEDOUT: 2413 /* 2414 * Problem reaching the server. Disconnect and let the 2415 * forechannel reestablish the connection. The server will 2416 * have to retransmit the backchannel request and we'll 2417 * reprocess it. Since these ops are idempotent, there's no 2418 * need to cache our reply at this time. 2419 */ 2420 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2421 "error: %d\n", task->tk_status); 2422 xprt_conditional_disconnect(req->rq_xprt, 2423 req->rq_connect_cookie); 2424 break; 2425 default: 2426 /* 2427 * We were unable to reply and will have to drop the 2428 * request. The server should reconnect and retransmit. 2429 */ 2430 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2431 "error: %d\n", task->tk_status); 2432 break; 2433 } 2434 task->tk_action = rpc_exit_task; 2435 } 2436 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2437 2438 /* 2439 * 6. Sort out the RPC call status 2440 */ 2441 static void 2442 call_status(struct rpc_task *task) 2443 { 2444 struct rpc_clnt *clnt = task->tk_client; 2445 int status; 2446 2447 if (!task->tk_msg.rpc_proc->p_proc) 2448 trace_xprt_ping(task->tk_xprt, task->tk_status); 2449 2450 status = task->tk_status; 2451 if (status >= 0) { 2452 task->tk_action = call_decode; 2453 return; 2454 } 2455 2456 trace_rpc_call_status(task); 2457 task->tk_status = 0; 2458 switch(status) { 2459 case -EHOSTDOWN: 2460 case -ENETDOWN: 2461 case -EHOSTUNREACH: 2462 case -ENETUNREACH: 2463 case -EPERM: 2464 if (RPC_IS_SOFTCONN(task)) 2465 goto out_exit; 2466 /* 2467 * Delay any retries for 3 seconds, then handle as if it 2468 * were a timeout. 2469 */ 2470 rpc_delay(task, 3*HZ); 2471 fallthrough; 2472 case -ETIMEDOUT: 2473 break; 2474 case -ECONNREFUSED: 2475 case -ECONNRESET: 2476 case -ECONNABORTED: 2477 case -ENOTCONN: 2478 rpc_force_rebind(clnt); 2479 break; 2480 case -EADDRINUSE: 2481 rpc_delay(task, 3*HZ); 2482 fallthrough; 2483 case -EPIPE: 2484 case -EAGAIN: 2485 break; 2486 case -ENFILE: 2487 case -ENOBUFS: 2488 case -ENOMEM: 2489 rpc_delay(task, HZ>>2); 2490 break; 2491 case -EIO: 2492 /* shutdown or soft timeout */ 2493 goto out_exit; 2494 default: 2495 if (clnt->cl_chatty) 2496 printk("%s: RPC call returned error %d\n", 2497 clnt->cl_program->name, -status); 2498 goto out_exit; 2499 } 2500 task->tk_action = call_encode; 2501 rpc_check_timeout(task); 2502 return; 2503 out_exit: 2504 rpc_call_rpcerror(task, status); 2505 } 2506 2507 static bool 2508 rpc_check_connected(const struct rpc_rqst *req) 2509 { 2510 /* No allocated request or transport? return true */ 2511 if (!req || !req->rq_xprt) 2512 return true; 2513 return xprt_connected(req->rq_xprt); 2514 } 2515 2516 static void 2517 rpc_check_timeout(struct rpc_task *task) 2518 { 2519 struct rpc_clnt *clnt = task->tk_client; 2520 2521 if (RPC_SIGNALLED(task)) 2522 return; 2523 2524 if (xprt_adjust_timeout(task->tk_rqstp) == 0) 2525 return; 2526 2527 trace_rpc_timeout_status(task); 2528 task->tk_timeouts++; 2529 2530 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) { 2531 rpc_call_rpcerror(task, -ETIMEDOUT); 2532 return; 2533 } 2534 2535 if (RPC_IS_SOFT(task)) { 2536 /* 2537 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has 2538 * been sent, it should time out only if the transport 2539 * connection gets terminally broken. 2540 */ 2541 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && 2542 rpc_check_connected(task->tk_rqstp)) 2543 return; 2544 2545 if (clnt->cl_chatty) { 2546 pr_notice_ratelimited( 2547 "%s: server %s not responding, timed out\n", 2548 clnt->cl_program->name, 2549 task->tk_xprt->servername); 2550 } 2551 if (task->tk_flags & RPC_TASK_TIMEOUT) 2552 rpc_call_rpcerror(task, -ETIMEDOUT); 2553 else 2554 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT); 2555 return; 2556 } 2557 2558 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2559 task->tk_flags |= RPC_CALL_MAJORSEEN; 2560 if (clnt->cl_chatty) { 2561 pr_notice_ratelimited( 2562 "%s: server %s not responding, still trying\n", 2563 clnt->cl_program->name, 2564 task->tk_xprt->servername); 2565 } 2566 } 2567 rpc_force_rebind(clnt); 2568 /* 2569 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2570 * event? RFC2203 requires the server to drop all such requests. 2571 */ 2572 rpcauth_invalcred(task); 2573 } 2574 2575 /* 2576 * 7. Decode the RPC reply 2577 */ 2578 static void 2579 call_decode(struct rpc_task *task) 2580 { 2581 struct rpc_clnt *clnt = task->tk_client; 2582 struct rpc_rqst *req = task->tk_rqstp; 2583 struct xdr_stream xdr; 2584 int err; 2585 2586 if (!task->tk_msg.rpc_proc->p_decode) { 2587 task->tk_action = rpc_exit_task; 2588 return; 2589 } 2590 2591 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2592 if (clnt->cl_chatty) { 2593 pr_notice_ratelimited("%s: server %s OK\n", 2594 clnt->cl_program->name, 2595 task->tk_xprt->servername); 2596 } 2597 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2598 } 2599 2600 /* 2601 * Did we ever call xprt_complete_rqst()? If not, we should assume 2602 * the message is incomplete. 2603 */ 2604 err = -EAGAIN; 2605 if (!req->rq_reply_bytes_recvd) 2606 goto out; 2607 2608 /* Ensure that we see all writes made by xprt_complete_rqst() 2609 * before it changed req->rq_reply_bytes_recvd. 2610 */ 2611 smp_rmb(); 2612 2613 req->rq_rcv_buf.len = req->rq_private_buf.len; 2614 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf); 2615 2616 /* Check that the softirq receive buffer is valid */ 2617 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2618 sizeof(req->rq_rcv_buf)) != 0); 2619 2620 xdr_init_decode(&xdr, &req->rq_rcv_buf, 2621 req->rq_rcv_buf.head[0].iov_base, req); 2622 err = rpc_decode_header(task, &xdr); 2623 out: 2624 switch (err) { 2625 case 0: 2626 task->tk_action = rpc_exit_task; 2627 task->tk_status = rpcauth_unwrap_resp(task, &xdr); 2628 xdr_finish_decode(&xdr); 2629 return; 2630 case -EAGAIN: 2631 task->tk_status = 0; 2632 if (task->tk_client->cl_discrtry) 2633 xprt_conditional_disconnect(req->rq_xprt, 2634 req->rq_connect_cookie); 2635 task->tk_action = call_encode; 2636 rpc_check_timeout(task); 2637 break; 2638 case -EKEYREJECTED: 2639 task->tk_action = call_reserve; 2640 rpc_check_timeout(task); 2641 rpcauth_invalcred(task); 2642 /* Ensure we obtain a new XID if we retry! */ 2643 xprt_release(task); 2644 } 2645 } 2646 2647 static int 2648 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr) 2649 { 2650 struct rpc_clnt *clnt = task->tk_client; 2651 struct rpc_rqst *req = task->tk_rqstp; 2652 __be32 *p; 2653 int error; 2654 2655 error = -EMSGSIZE; 2656 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2); 2657 if (!p) 2658 goto out_fail; 2659 *p++ = req->rq_xid; 2660 *p++ = rpc_call; 2661 *p++ = cpu_to_be32(RPC_VERSION); 2662 *p++ = cpu_to_be32(clnt->cl_prog); 2663 *p++ = cpu_to_be32(clnt->cl_vers); 2664 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc); 2665 2666 error = rpcauth_marshcred(task, xdr); 2667 if (error < 0) 2668 goto out_fail; 2669 return 0; 2670 out_fail: 2671 trace_rpc_bad_callhdr(task); 2672 rpc_call_rpcerror(task, error); 2673 return error; 2674 } 2675 2676 static noinline int 2677 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) 2678 { 2679 struct rpc_clnt *clnt = task->tk_client; 2680 int error; 2681 __be32 *p; 2682 2683 /* RFC-1014 says that the representation of XDR data must be a 2684 * multiple of four bytes 2685 * - if it isn't pointer subtraction in the NFS client may give 2686 * undefined results 2687 */ 2688 if (task->tk_rqstp->rq_rcv_buf.len & 3) 2689 goto out_unparsable; 2690 2691 p = xdr_inline_decode(xdr, 3 * sizeof(*p)); 2692 if (!p) 2693 goto out_unparsable; 2694 p++; /* skip XID */ 2695 if (*p++ != rpc_reply) 2696 goto out_unparsable; 2697 if (*p++ != rpc_msg_accepted) 2698 goto out_msg_denied; 2699 2700 error = rpcauth_checkverf(task, xdr); 2701 if (error) 2702 goto out_verifier; 2703 2704 p = xdr_inline_decode(xdr, sizeof(*p)); 2705 if (!p) 2706 goto out_unparsable; 2707 switch (*p) { 2708 case rpc_success: 2709 return 0; 2710 case rpc_prog_unavail: 2711 trace_rpc__prog_unavail(task); 2712 error = -EPFNOSUPPORT; 2713 goto out_err; 2714 case rpc_prog_mismatch: 2715 trace_rpc__prog_mismatch(task); 2716 error = -EPROTONOSUPPORT; 2717 goto out_err; 2718 case rpc_proc_unavail: 2719 trace_rpc__proc_unavail(task); 2720 error = -EOPNOTSUPP; 2721 goto out_err; 2722 case rpc_garbage_args: 2723 case rpc_system_err: 2724 trace_rpc__garbage_args(task); 2725 error = -EIO; 2726 break; 2727 default: 2728 goto out_unparsable; 2729 } 2730 2731 out_garbage: 2732 clnt->cl_stats->rpcgarbage++; 2733 if (task->tk_garb_retry) { 2734 task->tk_garb_retry--; 2735 task->tk_action = call_encode; 2736 return -EAGAIN; 2737 } 2738 out_err: 2739 rpc_call_rpcerror(task, error); 2740 return error; 2741 2742 out_unparsable: 2743 trace_rpc__unparsable(task); 2744 error = -EIO; 2745 goto out_garbage; 2746 2747 out_verifier: 2748 trace_rpc_bad_verifier(task); 2749 switch (error) { 2750 case -EPROTONOSUPPORT: 2751 goto out_err; 2752 case -EACCES: 2753 /* Re-encode with a fresh cred */ 2754 fallthrough; 2755 default: 2756 goto out_garbage; 2757 } 2758 2759 out_msg_denied: 2760 error = -EACCES; 2761 p = xdr_inline_decode(xdr, sizeof(*p)); 2762 if (!p) 2763 goto out_unparsable; 2764 switch (*p++) { 2765 case rpc_auth_error: 2766 break; 2767 case rpc_mismatch: 2768 trace_rpc__mismatch(task); 2769 error = -EPROTONOSUPPORT; 2770 goto out_err; 2771 default: 2772 goto out_unparsable; 2773 } 2774 2775 p = xdr_inline_decode(xdr, sizeof(*p)); 2776 if (!p) 2777 goto out_unparsable; 2778 switch (*p++) { 2779 case rpc_autherr_rejectedcred: 2780 case rpc_autherr_rejectedverf: 2781 case rpcsec_gsserr_credproblem: 2782 case rpcsec_gsserr_ctxproblem: 2783 rpcauth_invalcred(task); 2784 if (!task->tk_cred_retry) 2785 break; 2786 task->tk_cred_retry--; 2787 trace_rpc__stale_creds(task); 2788 return -EKEYREJECTED; 2789 case rpc_autherr_badcred: 2790 case rpc_autherr_badverf: 2791 /* possibly garbled cred/verf? */ 2792 if (!task->tk_garb_retry) 2793 break; 2794 task->tk_garb_retry--; 2795 trace_rpc__bad_creds(task); 2796 task->tk_action = call_encode; 2797 return -EAGAIN; 2798 case rpc_autherr_tooweak: 2799 trace_rpc__auth_tooweak(task); 2800 pr_warn("RPC: server %s requires stronger authentication.\n", 2801 task->tk_xprt->servername); 2802 break; 2803 default: 2804 goto out_unparsable; 2805 } 2806 goto out_err; 2807 } 2808 2809 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2810 const void *obj) 2811 { 2812 } 2813 2814 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2815 void *obj) 2816 { 2817 return 0; 2818 } 2819 2820 static const struct rpc_procinfo rpcproc_null = { 2821 .p_encode = rpcproc_encode_null, 2822 .p_decode = rpcproc_decode_null, 2823 }; 2824 2825 static const struct rpc_procinfo rpcproc_null_noreply = { 2826 .p_encode = rpcproc_encode_null, 2827 }; 2828 2829 static void 2830 rpc_null_call_prepare(struct rpc_task *task, void *data) 2831 { 2832 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT; 2833 rpc_call_start(task); 2834 } 2835 2836 static const struct rpc_call_ops rpc_null_ops = { 2837 .rpc_call_prepare = rpc_null_call_prepare, 2838 .rpc_call_done = rpc_default_callback, 2839 }; 2840 2841 static 2842 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2843 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2844 const struct rpc_call_ops *ops, void *data) 2845 { 2846 struct rpc_message msg = { 2847 .rpc_proc = &rpcproc_null, 2848 }; 2849 struct rpc_task_setup task_setup_data = { 2850 .rpc_client = clnt, 2851 .rpc_xprt = xprt, 2852 .rpc_message = &msg, 2853 .rpc_op_cred = cred, 2854 .callback_ops = ops ?: &rpc_null_ops, 2855 .callback_data = data, 2856 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN | 2857 RPC_TASK_NULLCREDS, 2858 }; 2859 2860 return rpc_run_task(&task_setup_data); 2861 } 2862 2863 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2864 { 2865 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2866 } 2867 EXPORT_SYMBOL_GPL(rpc_call_null); 2868 2869 static int rpc_ping(struct rpc_clnt *clnt) 2870 { 2871 struct rpc_task *task; 2872 int status; 2873 2874 if (clnt->cl_auth->au_ops->ping) 2875 return clnt->cl_auth->au_ops->ping(clnt); 2876 2877 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL); 2878 if (IS_ERR(task)) 2879 return PTR_ERR(task); 2880 status = task->tk_status; 2881 rpc_put_task(task); 2882 return status; 2883 } 2884 2885 static int rpc_ping_noreply(struct rpc_clnt *clnt) 2886 { 2887 struct rpc_message msg = { 2888 .rpc_proc = &rpcproc_null_noreply, 2889 }; 2890 struct rpc_task_setup task_setup_data = { 2891 .rpc_client = clnt, 2892 .rpc_message = &msg, 2893 .callback_ops = &rpc_null_ops, 2894 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS, 2895 }; 2896 struct rpc_task *task; 2897 int status; 2898 2899 task = rpc_run_task(&task_setup_data); 2900 if (IS_ERR(task)) 2901 return PTR_ERR(task); 2902 status = task->tk_status; 2903 rpc_put_task(task); 2904 return status; 2905 } 2906 2907 struct rpc_cb_add_xprt_calldata { 2908 struct rpc_xprt_switch *xps; 2909 struct rpc_xprt *xprt; 2910 }; 2911 2912 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2913 { 2914 struct rpc_cb_add_xprt_calldata *data = calldata; 2915 2916 if (task->tk_status == 0) 2917 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2918 } 2919 2920 static void rpc_cb_add_xprt_release(void *calldata) 2921 { 2922 struct rpc_cb_add_xprt_calldata *data = calldata; 2923 2924 xprt_put(data->xprt); 2925 xprt_switch_put(data->xps); 2926 kfree(data); 2927 } 2928 2929 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2930 .rpc_call_prepare = rpc_null_call_prepare, 2931 .rpc_call_done = rpc_cb_add_xprt_done, 2932 .rpc_release = rpc_cb_add_xprt_release, 2933 }; 2934 2935 /** 2936 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2937 * @clnt: pointer to struct rpc_clnt 2938 * @xps: pointer to struct rpc_xprt_switch, 2939 * @xprt: pointer struct rpc_xprt 2940 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport 2941 */ 2942 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2943 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2944 void *in_max_connect) 2945 { 2946 struct rpc_cb_add_xprt_calldata *data; 2947 struct rpc_task *task; 2948 int max_connect = clnt->cl_max_connect; 2949 2950 if (in_max_connect) 2951 max_connect = *(int *)in_max_connect; 2952 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) { 2953 rcu_read_lock(); 2954 pr_warn("SUNRPC: reached max allowed number (%d) did not add " 2955 "transport to server: %s\n", max_connect, 2956 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 2957 rcu_read_unlock(); 2958 return -EINVAL; 2959 } 2960 2961 data = kmalloc(sizeof(*data), GFP_KERNEL); 2962 if (!data) 2963 return -ENOMEM; 2964 data->xps = xprt_switch_get(xps); 2965 data->xprt = xprt_get(xprt); 2966 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) { 2967 rpc_cb_add_xprt_release(data); 2968 goto success; 2969 } 2970 2971 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC, 2972 &rpc_cb_add_xprt_call_ops, data); 2973 if (IS_ERR(task)) 2974 return PTR_ERR(task); 2975 2976 data->xps->xps_nunique_destaddr_xprts++; 2977 rpc_put_task(task); 2978 success: 2979 return 1; 2980 } 2981 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2982 2983 static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt, 2984 struct rpc_xprt *xprt, 2985 struct rpc_add_xprt_test *data) 2986 { 2987 struct rpc_task *task; 2988 int status = -EADDRINUSE; 2989 2990 /* Test the connection */ 2991 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL); 2992 if (IS_ERR(task)) 2993 return PTR_ERR(task); 2994 2995 status = task->tk_status; 2996 rpc_put_task(task); 2997 2998 if (status < 0) 2999 return status; 3000 3001 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ 3002 data->add_xprt_test(clnt, xprt, data->data); 3003 3004 return 0; 3005 } 3006 3007 /** 3008 * rpc_clnt_setup_test_and_add_xprt() 3009 * 3010 * This is an rpc_clnt_add_xprt setup() function which returns 1 so: 3011 * 1) caller of the test function must dereference the rpc_xprt_switch 3012 * and the rpc_xprt. 3013 * 2) test function must call rpc_xprt_switch_add_xprt, usually in 3014 * the rpc_call_done routine. 3015 * 3016 * Upon success (return of 1), the test function adds the new 3017 * transport to the rpc_clnt xprt switch 3018 * 3019 * @clnt: struct rpc_clnt to get the new transport 3020 * @xps: the rpc_xprt_switch to hold the new transport 3021 * @xprt: the rpc_xprt to test 3022 * @data: a struct rpc_add_xprt_test pointer that holds the test function 3023 * and test function call data 3024 */ 3025 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, 3026 struct rpc_xprt_switch *xps, 3027 struct rpc_xprt *xprt, 3028 void *data) 3029 { 3030 int status = -EADDRINUSE; 3031 3032 xprt = xprt_get(xprt); 3033 xprt_switch_get(xps); 3034 3035 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) 3036 goto out_err; 3037 3038 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3039 if (status < 0) 3040 goto out_err; 3041 3042 status = 1; 3043 out_err: 3044 xprt_put(xprt); 3045 xprt_switch_put(xps); 3046 if (status < 0) 3047 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not " 3048 "added\n", status, 3049 xprt->address_strings[RPC_DISPLAY_ADDR]); 3050 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ 3051 return status; 3052 } 3053 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); 3054 3055 /** 3056 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 3057 * @clnt: pointer to struct rpc_clnt 3058 * @xprtargs: pointer to struct xprt_create 3059 * @setup: callback to test and/or set up the connection 3060 * @data: pointer to setup function data 3061 * 3062 * Creates a new transport using the parameters set in args and 3063 * adds it to clnt. 3064 * If ping is set, then test that connectivity succeeds before 3065 * adding the new transport. 3066 * 3067 */ 3068 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 3069 struct xprt_create *xprtargs, 3070 int (*setup)(struct rpc_clnt *, 3071 struct rpc_xprt_switch *, 3072 struct rpc_xprt *, 3073 void *), 3074 void *data) 3075 { 3076 struct rpc_xprt_switch *xps; 3077 struct rpc_xprt *xprt; 3078 unsigned long connect_timeout; 3079 unsigned long reconnect_timeout; 3080 unsigned char resvport, reuseport; 3081 int ret = 0, ident; 3082 3083 rcu_read_lock(); 3084 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3085 xprt = xprt_iter_xprt(&clnt->cl_xpi); 3086 if (xps == NULL || xprt == NULL) { 3087 rcu_read_unlock(); 3088 xprt_switch_put(xps); 3089 return -EAGAIN; 3090 } 3091 resvport = xprt->resvport; 3092 reuseport = xprt->reuseport; 3093 connect_timeout = xprt->connect_timeout; 3094 reconnect_timeout = xprt->max_reconnect_timeout; 3095 ident = xprt->xprt_class->ident; 3096 rcu_read_unlock(); 3097 3098 if (!xprtargs->ident) 3099 xprtargs->ident = ident; 3100 xprtargs->xprtsec = clnt->cl_xprtsec; 3101 xprt = xprt_create_transport(xprtargs); 3102 if (IS_ERR(xprt)) { 3103 ret = PTR_ERR(xprt); 3104 goto out_put_switch; 3105 } 3106 xprt->resvport = resvport; 3107 xprt->reuseport = reuseport; 3108 3109 if (xprtargs->connect_timeout) 3110 connect_timeout = xprtargs->connect_timeout; 3111 if (xprtargs->reconnect_timeout) 3112 reconnect_timeout = xprtargs->reconnect_timeout; 3113 if (xprt->ops->set_connect_timeout != NULL) 3114 xprt->ops->set_connect_timeout(xprt, 3115 connect_timeout, 3116 reconnect_timeout); 3117 3118 rpc_xprt_switch_set_roundrobin(xps); 3119 if (setup) { 3120 ret = setup(clnt, xps, xprt, data); 3121 if (ret != 0) 3122 goto out_put_xprt; 3123 } 3124 rpc_xprt_switch_add_xprt(xps, xprt); 3125 out_put_xprt: 3126 xprt_put(xprt); 3127 out_put_switch: 3128 xprt_switch_put(xps); 3129 return ret; 3130 } 3131 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 3132 3133 static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt, 3134 struct rpc_xprt *xprt, 3135 struct rpc_add_xprt_test *data) 3136 { 3137 struct rpc_xprt *main_xprt; 3138 int status = 0; 3139 3140 xprt_get(xprt); 3141 3142 rcu_read_lock(); 3143 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3144 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3145 (struct sockaddr *)&main_xprt->addr); 3146 rcu_read_unlock(); 3147 xprt_put(main_xprt); 3148 if (status || !test_bit(XPRT_OFFLINE, &xprt->state)) 3149 goto out; 3150 3151 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3152 out: 3153 xprt_put(xprt); 3154 return status; 3155 } 3156 3157 /* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking 3158 * @clnt rpc_clnt structure 3159 * 3160 * For each offlined transport found in the rpc_clnt structure call 3161 * the function rpc_xprt_probe_trunked() which will determine if this 3162 * transport still belongs to the trunking group. 3163 */ 3164 void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt, 3165 struct rpc_add_xprt_test *data) 3166 { 3167 struct rpc_xprt_iter xpi; 3168 int ret; 3169 3170 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi); 3171 if (ret) 3172 return; 3173 for (;;) { 3174 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 3175 3176 if (!xprt) 3177 break; 3178 ret = rpc_xprt_probe_trunked(clnt, xprt, data); 3179 xprt_put(xprt); 3180 if (ret < 0) 3181 break; 3182 xprt_iter_rewind(&xpi); 3183 } 3184 xprt_iter_destroy(&xpi); 3185 } 3186 EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts); 3187 3188 static int rpc_xprt_offline(struct rpc_clnt *clnt, 3189 struct rpc_xprt *xprt, 3190 void *data) 3191 { 3192 struct rpc_xprt *main_xprt; 3193 struct rpc_xprt_switch *xps; 3194 int err = 0; 3195 3196 xprt_get(xprt); 3197 3198 rcu_read_lock(); 3199 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3200 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3201 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3202 (struct sockaddr *)&main_xprt->addr); 3203 rcu_read_unlock(); 3204 xprt_put(main_xprt); 3205 if (err) 3206 goto out; 3207 3208 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) { 3209 err = -EINTR; 3210 goto out; 3211 } 3212 xprt_set_offline_locked(xprt, xps); 3213 3214 xprt_release_write(xprt, NULL); 3215 out: 3216 xprt_put(xprt); 3217 xprt_switch_put(xps); 3218 return err; 3219 } 3220 3221 /* rpc_clnt_manage_trunked_xprts -- offline trunked transports 3222 * @clnt rpc_clnt structure 3223 * 3224 * For each active transport found in the rpc_clnt structure call 3225 * the function rpc_xprt_offline() which will identify trunked transports 3226 * and will mark them offline. 3227 */ 3228 void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt) 3229 { 3230 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL); 3231 } 3232 EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts); 3233 3234 struct connect_timeout_data { 3235 unsigned long connect_timeout; 3236 unsigned long reconnect_timeout; 3237 }; 3238 3239 static int 3240 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, 3241 struct rpc_xprt *xprt, 3242 void *data) 3243 { 3244 struct connect_timeout_data *timeo = data; 3245 3246 if (xprt->ops->set_connect_timeout) 3247 xprt->ops->set_connect_timeout(xprt, 3248 timeo->connect_timeout, 3249 timeo->reconnect_timeout); 3250 return 0; 3251 } 3252 3253 void 3254 rpc_set_connect_timeout(struct rpc_clnt *clnt, 3255 unsigned long connect_timeout, 3256 unsigned long reconnect_timeout) 3257 { 3258 struct connect_timeout_data timeout = { 3259 .connect_timeout = connect_timeout, 3260 .reconnect_timeout = reconnect_timeout, 3261 }; 3262 rpc_clnt_iterate_for_each_xprt(clnt, 3263 rpc_xprt_set_connect_timeout, 3264 &timeout); 3265 } 3266 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); 3267 3268 void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3269 { 3270 struct rpc_xprt_switch *xps; 3271 3272 xps = rpc_clnt_xprt_switch_get(clnt); 3273 xprt_set_online_locked(xprt, xps); 3274 xprt_switch_put(xps); 3275 } 3276 3277 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3278 { 3279 struct rpc_xprt_switch *xps; 3280 3281 if (rpc_clnt_xprt_switch_has_addr(clnt, 3282 (const struct sockaddr *)&xprt->addr)) { 3283 return rpc_clnt_xprt_set_online(clnt, xprt); 3284 } 3285 3286 xps = rpc_clnt_xprt_switch_get(clnt); 3287 rpc_xprt_switch_add_xprt(xps, xprt); 3288 xprt_switch_put(xps); 3289 } 3290 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); 3291 3292 void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3293 { 3294 struct rpc_xprt_switch *xps; 3295 3296 rcu_read_lock(); 3297 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3298 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3299 xprt, 0); 3300 xps->xps_nunique_destaddr_xprts--; 3301 rcu_read_unlock(); 3302 } 3303 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt); 3304 3305 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, 3306 const struct sockaddr *sap) 3307 { 3308 struct rpc_xprt_switch *xps; 3309 bool ret; 3310 3311 rcu_read_lock(); 3312 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3313 ret = rpc_xprt_switch_has_addr(xps, sap); 3314 rcu_read_unlock(); 3315 return ret; 3316 } 3317 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); 3318 3319 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3320 static void rpc_show_header(void) 3321 { 3322 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 3323 "-timeout ---ops--\n"); 3324 } 3325 3326 static void rpc_show_task(const struct rpc_clnt *clnt, 3327 const struct rpc_task *task) 3328 { 3329 const char *rpc_waitq = "none"; 3330 3331 if (RPC_IS_QUEUED(task)) 3332 rpc_waitq = rpc_qname(task->tk_waitqueue); 3333 3334 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 3335 task->tk_pid, task->tk_flags, task->tk_status, 3336 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops, 3337 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 3338 task->tk_action, rpc_waitq); 3339 } 3340 3341 void rpc_show_tasks(struct net *net) 3342 { 3343 struct rpc_clnt *clnt; 3344 struct rpc_task *task; 3345 int header = 0; 3346 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 3347 3348 spin_lock(&sn->rpc_client_lock); 3349 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 3350 spin_lock(&clnt->cl_lock); 3351 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 3352 if (!header) { 3353 rpc_show_header(); 3354 header++; 3355 } 3356 rpc_show_task(clnt, task); 3357 } 3358 spin_unlock(&clnt->cl_lock); 3359 } 3360 spin_unlock(&sn->rpc_client_lock); 3361 } 3362 #endif 3363 3364 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 3365 static int 3366 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 3367 struct rpc_xprt *xprt, 3368 void *dummy) 3369 { 3370 return xprt_enable_swap(xprt); 3371 } 3372 3373 int 3374 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 3375 { 3376 while (clnt != clnt->cl_parent) 3377 clnt = clnt->cl_parent; 3378 if (atomic_inc_return(&clnt->cl_swapper) == 1) 3379 return rpc_clnt_iterate_for_each_xprt(clnt, 3380 rpc_clnt_swap_activate_callback, NULL); 3381 return 0; 3382 } 3383 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 3384 3385 static int 3386 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 3387 struct rpc_xprt *xprt, 3388 void *dummy) 3389 { 3390 xprt_disable_swap(xprt); 3391 return 0; 3392 } 3393 3394 void 3395 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 3396 { 3397 while (clnt != clnt->cl_parent) 3398 clnt = clnt->cl_parent; 3399 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 3400 rpc_clnt_iterate_for_each_xprt(clnt, 3401 rpc_clnt_swap_deactivate_callback, NULL); 3402 } 3403 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 3404 #endif /* CONFIG_SUNRPC_SWAP */ 3405