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