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