1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/net/sunrpc/clnt.c 4 * 5 * This file contains the high-level RPC interface. 6 * It is modeled as a finite state machine to support both synchronous 7 * and asynchronous requests. 8 * 9 * - RPC header generation and argument serialization. 10 * - Credential refresh. 11 * - TCP connect handling. 12 * - Retry of operation when it is suspected the operation failed because 13 * of uid squashing on the server, or when the credentials were stale 14 * and need to be refreshed, or when a packet was damaged in transit. 15 * This may be have to be moved to the VFS layer. 16 * 17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 19 */ 20 21 22 #include <linux/module.h> 23 #include <linux/types.h> 24 #include <linux/kallsyms.h> 25 #include <linux/mm.h> 26 #include <linux/namei.h> 27 #include <linux/mount.h> 28 #include <linux/slab.h> 29 #include <linux/rcupdate.h> 30 #include <linux/utsname.h> 31 #include <linux/workqueue.h> 32 #include <linux/in.h> 33 #include <linux/in6.h> 34 #include <linux/un.h> 35 36 #include <linux/sunrpc/clnt.h> 37 #include <linux/sunrpc/addr.h> 38 #include <linux/sunrpc/rpc_pipe_fs.h> 39 #include <linux/sunrpc/metrics.h> 40 #include <linux/sunrpc/bc_xprt.h> 41 #include <trace/events/sunrpc.h> 42 43 #include "sunrpc.h" 44 #include "sysfs.h" 45 #include "netns.h" 46 47 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 48 # define RPCDBG_FACILITY RPCDBG_CALL 49 #endif 50 51 /* 52 * All RPC clients are linked into this list 53 */ 54 55 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 56 57 58 static void call_start(struct rpc_task *task); 59 static void call_reserve(struct rpc_task *task); 60 static void call_reserveresult(struct rpc_task *task); 61 static void call_allocate(struct rpc_task *task); 62 static void call_encode(struct rpc_task *task); 63 static void call_decode(struct rpc_task *task); 64 static void call_bind(struct rpc_task *task); 65 static void call_bind_status(struct rpc_task *task); 66 static void call_transmit(struct rpc_task *task); 67 static void call_status(struct rpc_task *task); 68 static void call_transmit_status(struct rpc_task *task); 69 static void call_refresh(struct rpc_task *task); 70 static void call_refreshresult(struct rpc_task *task); 71 static void call_connect(struct rpc_task *task); 72 static void call_connect_status(struct rpc_task *task); 73 74 static int rpc_encode_header(struct rpc_task *task, 75 struct xdr_stream *xdr); 76 static int rpc_decode_header(struct rpc_task *task, 77 struct xdr_stream *xdr); 78 static int rpc_ping(struct rpc_clnt *clnt); 79 static int rpc_ping_noreply(struct rpc_clnt *clnt); 80 static void rpc_check_timeout(struct rpc_task *task); 81 82 static void rpc_register_client(struct rpc_clnt *clnt) 83 { 84 struct net *net = rpc_net_ns(clnt); 85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 86 87 spin_lock(&sn->rpc_client_lock); 88 list_add(&clnt->cl_clients, &sn->all_clients); 89 spin_unlock(&sn->rpc_client_lock); 90 } 91 92 static void rpc_unregister_client(struct rpc_clnt *clnt) 93 { 94 struct net *net = rpc_net_ns(clnt); 95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 96 97 spin_lock(&sn->rpc_client_lock); 98 list_del(&clnt->cl_clients); 99 spin_unlock(&sn->rpc_client_lock); 100 } 101 102 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 103 { 104 rpc_remove_client_dir(clnt); 105 } 106 107 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 108 { 109 struct net *net = rpc_net_ns(clnt); 110 struct super_block *pipefs_sb; 111 112 pipefs_sb = rpc_get_sb_net(net); 113 if (pipefs_sb) { 114 if (pipefs_sb == clnt->pipefs_sb) 115 __rpc_clnt_remove_pipedir(clnt); 116 rpc_put_sb_net(net); 117 } 118 } 119 120 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb, 121 struct rpc_clnt *clnt) 122 { 123 static uint32_t clntid; 124 const char *dir_name = clnt->cl_program->pipe_dir_name; 125 char name[15]; 126 struct dentry *dir, *dentry; 127 128 dir = rpc_d_lookup_sb(sb, dir_name); 129 if (dir == NULL) { 130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name); 131 return dir; 132 } 133 for (;;) { 134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++); 135 name[sizeof(name) - 1] = '\0'; 136 dentry = rpc_create_client_dir(dir, name, clnt); 137 if (!IS_ERR(dentry)) 138 break; 139 if (dentry == ERR_PTR(-EEXIST)) 140 continue; 141 printk(KERN_INFO "RPC: Couldn't create pipefs entry" 142 " %s/%s, error %ld\n", 143 dir_name, name, PTR_ERR(dentry)); 144 break; 145 } 146 dput(dir); 147 return dentry; 148 } 149 150 static int 151 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt) 152 { 153 struct dentry *dentry; 154 155 clnt->pipefs_sb = pipefs_sb; 156 157 if (clnt->cl_program->pipe_dir_name != NULL) { 158 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); 159 if (IS_ERR(dentry)) 160 return PTR_ERR(dentry); 161 } 162 return 0; 163 } 164 165 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 166 { 167 if (clnt->cl_program->pipe_dir_name == NULL) 168 return 1; 169 170 switch (event) { 171 case RPC_PIPEFS_MOUNT: 172 if (clnt->cl_pipedir_objects.pdh_dentry != NULL) 173 return 1; 174 if (refcount_read(&clnt->cl_count) == 0) 175 return 1; 176 break; 177 case RPC_PIPEFS_UMOUNT: 178 if (clnt->cl_pipedir_objects.pdh_dentry == NULL) 179 return 1; 180 break; 181 } 182 return 0; 183 } 184 185 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 186 struct super_block *sb) 187 { 188 struct dentry *dentry; 189 190 switch (event) { 191 case RPC_PIPEFS_MOUNT: 192 dentry = rpc_setup_pipedir_sb(sb, clnt); 193 if (!dentry) 194 return -ENOENT; 195 if (IS_ERR(dentry)) 196 return PTR_ERR(dentry); 197 break; 198 case RPC_PIPEFS_UMOUNT: 199 __rpc_clnt_remove_pipedir(clnt); 200 break; 201 default: 202 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 203 return -ENOTSUPP; 204 } 205 return 0; 206 } 207 208 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 209 struct super_block *sb) 210 { 211 int error = 0; 212 213 for (;; clnt = clnt->cl_parent) { 214 if (!rpc_clnt_skip_event(clnt, event)) 215 error = __rpc_clnt_handle_event(clnt, event, sb); 216 if (error || clnt == clnt->cl_parent) 217 break; 218 } 219 return error; 220 } 221 222 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 223 { 224 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 225 struct rpc_clnt *clnt; 226 227 spin_lock(&sn->rpc_client_lock); 228 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 229 if (rpc_clnt_skip_event(clnt, event)) 230 continue; 231 spin_unlock(&sn->rpc_client_lock); 232 return clnt; 233 } 234 spin_unlock(&sn->rpc_client_lock); 235 return NULL; 236 } 237 238 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 239 void *ptr) 240 { 241 struct super_block *sb = ptr; 242 struct rpc_clnt *clnt; 243 int error = 0; 244 245 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 246 error = __rpc_pipefs_event(clnt, event, sb); 247 if (error) 248 break; 249 } 250 return error; 251 } 252 253 static struct notifier_block rpc_clients_block = { 254 .notifier_call = rpc_pipefs_event, 255 .priority = SUNRPC_PIPEFS_RPC_PRIO, 256 }; 257 258 int rpc_clients_notifier_register(void) 259 { 260 return rpc_pipefs_notifier_register(&rpc_clients_block); 261 } 262 263 void rpc_clients_notifier_unregister(void) 264 { 265 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 266 } 267 268 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, 269 struct rpc_xprt *xprt, 270 const struct rpc_timeout *timeout) 271 { 272 struct rpc_xprt *old; 273 274 spin_lock(&clnt->cl_lock); 275 old = rcu_dereference_protected(clnt->cl_xprt, 276 lockdep_is_held(&clnt->cl_lock)); 277 278 if (!xprt_bound(xprt)) 279 clnt->cl_autobind = 1; 280 281 clnt->cl_timeout = timeout; 282 rcu_assign_pointer(clnt->cl_xprt, xprt); 283 spin_unlock(&clnt->cl_lock); 284 285 return old; 286 } 287 288 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 289 { 290 clnt->cl_nodelen = strlcpy(clnt->cl_nodename, 291 nodename, sizeof(clnt->cl_nodename)); 292 } 293 294 static int rpc_client_register(struct rpc_clnt *clnt, 295 rpc_authflavor_t pseudoflavor, 296 const char *client_name) 297 { 298 struct rpc_auth_create_args auth_args = { 299 .pseudoflavor = pseudoflavor, 300 .target_name = client_name, 301 }; 302 struct rpc_auth *auth; 303 struct net *net = rpc_net_ns(clnt); 304 struct super_block *pipefs_sb; 305 int err; 306 307 rpc_clnt_debugfs_register(clnt); 308 309 pipefs_sb = rpc_get_sb_net(net); 310 if (pipefs_sb) { 311 err = rpc_setup_pipedir(pipefs_sb, clnt); 312 if (err) 313 goto out; 314 } 315 316 rpc_register_client(clnt); 317 if (pipefs_sb) 318 rpc_put_sb_net(net); 319 320 auth = rpcauth_create(&auth_args, clnt); 321 if (IS_ERR(auth)) { 322 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 323 pseudoflavor); 324 err = PTR_ERR(auth); 325 goto err_auth; 326 } 327 return 0; 328 err_auth: 329 pipefs_sb = rpc_get_sb_net(net); 330 rpc_unregister_client(clnt); 331 __rpc_clnt_remove_pipedir(clnt); 332 out: 333 if (pipefs_sb) 334 rpc_put_sb_net(net); 335 rpc_sysfs_client_destroy(clnt); 336 rpc_clnt_debugfs_unregister(clnt); 337 return err; 338 } 339 340 static DEFINE_IDA(rpc_clids); 341 342 void rpc_cleanup_clids(void) 343 { 344 ida_destroy(&rpc_clids); 345 } 346 347 static int rpc_alloc_clid(struct rpc_clnt *clnt) 348 { 349 int clid; 350 351 clid = ida_alloc(&rpc_clids, GFP_KERNEL); 352 if (clid < 0) 353 return clid; 354 clnt->cl_clid = clid; 355 return 0; 356 } 357 358 static void rpc_free_clid(struct rpc_clnt *clnt) 359 { 360 ida_free(&rpc_clids, clnt->cl_clid); 361 } 362 363 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 364 struct rpc_xprt_switch *xps, 365 struct rpc_xprt *xprt, 366 struct rpc_clnt *parent) 367 { 368 const struct rpc_program *program = args->program; 369 const struct rpc_version *version; 370 struct rpc_clnt *clnt = NULL; 371 const struct rpc_timeout *timeout; 372 const char *nodename = args->nodename; 373 int err; 374 375 err = rpciod_up(); 376 if (err) 377 goto out_no_rpciod; 378 379 err = -EINVAL; 380 if (args->version >= program->nrvers) 381 goto out_err; 382 version = program->version[args->version]; 383 if (version == NULL) 384 goto out_err; 385 386 err = -ENOMEM; 387 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 388 if (!clnt) 389 goto out_err; 390 clnt->cl_parent = parent ? : clnt; 391 clnt->cl_xprtsec = args->xprtsec; 392 393 err = rpc_alloc_clid(clnt); 394 if (err) 395 goto out_no_clid; 396 397 clnt->cl_cred = get_cred(args->cred); 398 clnt->cl_procinfo = version->procs; 399 clnt->cl_maxproc = version->nrprocs; 400 clnt->cl_prog = args->prognumber ? : program->number; 401 clnt->cl_vers = version->number; 402 clnt->cl_stats = args->stats ? : program->stats; 403 clnt->cl_metrics = rpc_alloc_iostats(clnt); 404 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 405 err = -ENOMEM; 406 if (clnt->cl_metrics == NULL) 407 goto out_no_stats; 408 clnt->cl_program = program; 409 INIT_LIST_HEAD(&clnt->cl_tasks); 410 spin_lock_init(&clnt->cl_lock); 411 412 timeout = xprt->timeout; 413 if (args->timeout != NULL) { 414 memcpy(&clnt->cl_timeout_default, args->timeout, 415 sizeof(clnt->cl_timeout_default)); 416 timeout = &clnt->cl_timeout_default; 417 } 418 419 rpc_clnt_set_transport(clnt, xprt, timeout); 420 xprt->main = true; 421 xprt_iter_init(&clnt->cl_xpi, xps); 422 xprt_switch_put(xps); 423 424 clnt->cl_rtt = &clnt->cl_rtt_default; 425 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 426 427 refcount_set(&clnt->cl_count, 1); 428 429 if (nodename == NULL) 430 nodename = utsname()->nodename; 431 /* save the nodename */ 432 rpc_clnt_set_nodename(clnt, nodename); 433 434 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt)); 435 err = rpc_client_register(clnt, args->authflavor, args->client_name); 436 if (err) 437 goto out_no_path; 438 if (parent) 439 refcount_inc(&parent->cl_count); 440 441 trace_rpc_clnt_new(clnt, xprt, args); 442 return clnt; 443 444 out_no_path: 445 rpc_free_iostats(clnt->cl_metrics); 446 out_no_stats: 447 put_cred(clnt->cl_cred); 448 rpc_free_clid(clnt); 449 out_no_clid: 450 kfree(clnt); 451 out_err: 452 rpciod_down(); 453 out_no_rpciod: 454 xprt_switch_put(xps); 455 xprt_put(xprt); 456 trace_rpc_clnt_new_err(program->name, args->servername, err); 457 return ERR_PTR(err); 458 } 459 460 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 461 struct rpc_xprt *xprt) 462 { 463 struct rpc_clnt *clnt = NULL; 464 struct rpc_xprt_switch *xps; 465 466 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) { 467 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 468 xps = args->bc_xprt->xpt_bc_xps; 469 xprt_switch_get(xps); 470 } else { 471 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 472 if (xps == NULL) { 473 xprt_put(xprt); 474 return ERR_PTR(-ENOMEM); 475 } 476 if (xprt->bc_xprt) { 477 xprt_switch_get(xps); 478 xprt->bc_xprt->xpt_bc_xps = xps; 479 } 480 } 481 clnt = rpc_new_client(args, xps, xprt, NULL); 482 if (IS_ERR(clnt)) 483 return clnt; 484 485 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 486 int err = rpc_ping(clnt); 487 if (err != 0) { 488 rpc_shutdown_client(clnt); 489 return ERR_PTR(err); 490 } 491 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) { 492 int err = rpc_ping_noreply(clnt); 493 if (err != 0) { 494 rpc_shutdown_client(clnt); 495 return ERR_PTR(err); 496 } 497 } 498 499 clnt->cl_softrtry = 1; 500 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) { 501 clnt->cl_softrtry = 0; 502 if (args->flags & RPC_CLNT_CREATE_SOFTERR) 503 clnt->cl_softerr = 1; 504 } 505 506 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 507 clnt->cl_autobind = 1; 508 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 509 clnt->cl_noretranstimeo = 1; 510 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 511 clnt->cl_discrtry = 1; 512 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 513 clnt->cl_chatty = 1; 514 515 return clnt; 516 } 517 518 /** 519 * rpc_create - create an RPC client and transport with one call 520 * @args: rpc_clnt create argument structure 521 * 522 * Creates and initializes an RPC transport and an RPC client. 523 * 524 * It can ping the server in order to determine if it is up, and to see if 525 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 526 * this behavior so asynchronous tasks can also use rpc_create. 527 */ 528 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 529 { 530 struct rpc_xprt *xprt; 531 struct xprt_create xprtargs = { 532 .net = args->net, 533 .ident = args->protocol, 534 .srcaddr = args->saddress, 535 .dstaddr = args->address, 536 .addrlen = args->addrsize, 537 .servername = args->servername, 538 .bc_xprt = args->bc_xprt, 539 .xprtsec = args->xprtsec, 540 .connect_timeout = args->connect_timeout, 541 .reconnect_timeout = args->reconnect_timeout, 542 }; 543 char servername[48]; 544 struct rpc_clnt *clnt; 545 int i; 546 547 if (args->bc_xprt) { 548 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC)); 549 xprt = args->bc_xprt->xpt_bc_xprt; 550 if (xprt) { 551 xprt_get(xprt); 552 return rpc_create_xprt(args, xprt); 553 } 554 } 555 556 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 557 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 558 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 559 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 560 /* 561 * If the caller chooses not to specify a hostname, whip 562 * up a string representation of the passed-in address. 563 */ 564 if (xprtargs.servername == NULL) { 565 struct sockaddr_un *sun = 566 (struct sockaddr_un *)args->address; 567 struct sockaddr_in *sin = 568 (struct sockaddr_in *)args->address; 569 struct sockaddr_in6 *sin6 = 570 (struct sockaddr_in6 *)args->address; 571 572 servername[0] = '\0'; 573 switch (args->address->sa_family) { 574 case AF_LOCAL: 575 if (sun->sun_path[0]) 576 snprintf(servername, sizeof(servername), "%s", 577 sun->sun_path); 578 else 579 snprintf(servername, sizeof(servername), "@%s", 580 sun->sun_path+1); 581 break; 582 case AF_INET: 583 snprintf(servername, sizeof(servername), "%pI4", 584 &sin->sin_addr.s_addr); 585 break; 586 case AF_INET6: 587 snprintf(servername, sizeof(servername), "%pI6", 588 &sin6->sin6_addr); 589 break; 590 default: 591 /* caller wants default server name, but 592 * address family isn't recognized. */ 593 return ERR_PTR(-EINVAL); 594 } 595 xprtargs.servername = servername; 596 } 597 598 xprt = xprt_create_transport(&xprtargs); 599 if (IS_ERR(xprt)) 600 return (struct rpc_clnt *)xprt; 601 602 /* 603 * By default, kernel RPC client connects from a reserved port. 604 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 605 * but it is always enabled for rpciod, which handles the connect 606 * operation. 607 */ 608 xprt->resvport = 1; 609 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 610 xprt->resvport = 0; 611 xprt->reuseport = 0; 612 if (args->flags & RPC_CLNT_CREATE_REUSEPORT) 613 xprt->reuseport = 1; 614 615 clnt = rpc_create_xprt(args, xprt); 616 if (IS_ERR(clnt) || args->nconnect <= 1) 617 return clnt; 618 619 for (i = 0; i < args->nconnect - 1; i++) { 620 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0) 621 break; 622 } 623 return clnt; 624 } 625 EXPORT_SYMBOL_GPL(rpc_create); 626 627 /* 628 * This function clones the RPC client structure. It allows us to share the 629 * same transport while varying parameters such as the authentication 630 * flavour. 631 */ 632 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 633 struct rpc_clnt *clnt) 634 { 635 struct rpc_xprt_switch *xps; 636 struct rpc_xprt *xprt; 637 struct rpc_clnt *new; 638 int err; 639 640 err = -ENOMEM; 641 rcu_read_lock(); 642 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 643 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 644 rcu_read_unlock(); 645 if (xprt == NULL || xps == NULL) { 646 xprt_put(xprt); 647 xprt_switch_put(xps); 648 goto out_err; 649 } 650 args->servername = xprt->servername; 651 args->nodename = clnt->cl_nodename; 652 653 new = rpc_new_client(args, xps, xprt, clnt); 654 if (IS_ERR(new)) 655 return new; 656 657 /* Turn off autobind on clones */ 658 new->cl_autobind = 0; 659 new->cl_softrtry = clnt->cl_softrtry; 660 new->cl_softerr = clnt->cl_softerr; 661 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 662 new->cl_discrtry = clnt->cl_discrtry; 663 new->cl_chatty = clnt->cl_chatty; 664 new->cl_principal = clnt->cl_principal; 665 new->cl_max_connect = clnt->cl_max_connect; 666 return new; 667 668 out_err: 669 trace_rpc_clnt_clone_err(clnt, err); 670 return ERR_PTR(err); 671 } 672 673 /** 674 * rpc_clone_client - Clone an RPC client structure 675 * 676 * @clnt: RPC client whose parameters are copied 677 * 678 * Returns a fresh RPC client or an ERR_PTR. 679 */ 680 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 681 { 682 struct rpc_create_args args = { 683 .program = clnt->cl_program, 684 .prognumber = clnt->cl_prog, 685 .version = clnt->cl_vers, 686 .authflavor = clnt->cl_auth->au_flavor, 687 .cred = clnt->cl_cred, 688 .stats = clnt->cl_stats, 689 }; 690 return __rpc_clone_client(&args, clnt); 691 } 692 EXPORT_SYMBOL_GPL(rpc_clone_client); 693 694 /** 695 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 696 * 697 * @clnt: RPC client whose parameters are copied 698 * @flavor: security flavor for new client 699 * 700 * Returns a fresh RPC client or an ERR_PTR. 701 */ 702 struct rpc_clnt * 703 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 704 { 705 struct rpc_create_args args = { 706 .program = clnt->cl_program, 707 .prognumber = clnt->cl_prog, 708 .version = clnt->cl_vers, 709 .authflavor = flavor, 710 .cred = clnt->cl_cred, 711 .stats = clnt->cl_stats, 712 }; 713 return __rpc_clone_client(&args, clnt); 714 } 715 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 716 717 /** 718 * rpc_switch_client_transport: switch the RPC transport on the fly 719 * @clnt: pointer to a struct rpc_clnt 720 * @args: pointer to the new transport arguments 721 * @timeout: pointer to the new timeout parameters 722 * 723 * This function allows the caller to switch the RPC transport for the 724 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 725 * server, for instance. It assumes that the caller has ensured that 726 * there are no active RPC tasks by using some form of locking. 727 * 728 * Returns zero if "clnt" is now using the new xprt. Otherwise a 729 * negative errno is returned, and "clnt" continues to use the old 730 * xprt. 731 */ 732 int rpc_switch_client_transport(struct rpc_clnt *clnt, 733 struct xprt_create *args, 734 const struct rpc_timeout *timeout) 735 { 736 const struct rpc_timeout *old_timeo; 737 rpc_authflavor_t pseudoflavor; 738 struct rpc_xprt_switch *xps, *oldxps; 739 struct rpc_xprt *xprt, *old; 740 struct rpc_clnt *parent; 741 int err; 742 743 args->xprtsec = clnt->cl_xprtsec; 744 xprt = xprt_create_transport(args); 745 if (IS_ERR(xprt)) 746 return PTR_ERR(xprt); 747 748 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 749 if (xps == NULL) { 750 xprt_put(xprt); 751 return -ENOMEM; 752 } 753 754 pseudoflavor = clnt->cl_auth->au_flavor; 755 756 old_timeo = clnt->cl_timeout; 757 old = rpc_clnt_set_transport(clnt, xprt, timeout); 758 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps); 759 760 rpc_unregister_client(clnt); 761 __rpc_clnt_remove_pipedir(clnt); 762 rpc_sysfs_client_destroy(clnt); 763 rpc_clnt_debugfs_unregister(clnt); 764 765 /* 766 * A new transport was created. "clnt" therefore 767 * becomes the root of a new cl_parent tree. clnt's 768 * children, if it has any, still point to the old xprt. 769 */ 770 parent = clnt->cl_parent; 771 clnt->cl_parent = clnt; 772 773 /* 774 * The old rpc_auth cache cannot be re-used. GSS 775 * contexts in particular are between a single 776 * client and server. 777 */ 778 err = rpc_client_register(clnt, pseudoflavor, NULL); 779 if (err) 780 goto out_revert; 781 782 synchronize_rcu(); 783 if (parent != clnt) 784 rpc_release_client(parent); 785 xprt_switch_put(oldxps); 786 xprt_put(old); 787 trace_rpc_clnt_replace_xprt(clnt); 788 return 0; 789 790 out_revert: 791 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps); 792 rpc_clnt_set_transport(clnt, old, old_timeo); 793 clnt->cl_parent = parent; 794 rpc_client_register(clnt, pseudoflavor, NULL); 795 xprt_switch_put(xps); 796 xprt_put(xprt); 797 trace_rpc_clnt_replace_xprt_err(clnt); 798 return err; 799 } 800 EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 801 802 static 803 int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi, 804 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps)) 805 { 806 struct rpc_xprt_switch *xps; 807 808 rcu_read_lock(); 809 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 810 rcu_read_unlock(); 811 if (xps == NULL) 812 return -EAGAIN; 813 func(xpi, xps); 814 xprt_switch_put(xps); 815 return 0; 816 } 817 818 static 819 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi) 820 { 821 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall); 822 } 823 824 static 825 int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt, 826 struct rpc_xprt_iter *xpi) 827 { 828 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline); 829 } 830 831 /** 832 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports 833 * @clnt: pointer to client 834 * @fn: function to apply 835 * @data: void pointer to function data 836 * 837 * Iterates through the list of RPC transports currently attached to the 838 * client and applies the function fn(clnt, xprt, data). 839 * 840 * On error, the iteration stops, and the function returns the error value. 841 */ 842 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 843 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), 844 void *data) 845 { 846 struct rpc_xprt_iter xpi; 847 int ret; 848 849 ret = rpc_clnt_xprt_iter_init(clnt, &xpi); 850 if (ret) 851 return ret; 852 for (;;) { 853 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 854 855 if (!xprt) 856 break; 857 ret = fn(clnt, xprt, data); 858 xprt_put(xprt); 859 if (ret < 0) 860 break; 861 } 862 xprt_iter_destroy(&xpi); 863 return ret; 864 } 865 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); 866 867 /* 868 * Kill all tasks for the given client. 869 * XXX: kill their descendants as well? 870 */ 871 void rpc_killall_tasks(struct rpc_clnt *clnt) 872 { 873 struct rpc_task *rovr; 874 875 876 if (list_empty(&clnt->cl_tasks)) 877 return; 878 879 /* 880 * Spin lock all_tasks to prevent changes... 881 */ 882 trace_rpc_clnt_killall(clnt); 883 spin_lock(&clnt->cl_lock); 884 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) 885 rpc_signal_task(rovr); 886 spin_unlock(&clnt->cl_lock); 887 } 888 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 889 890 /** 891 * rpc_cancel_tasks - try to cancel a set of RPC tasks 892 * @clnt: Pointer to RPC client 893 * @error: RPC task error value to set 894 * @fnmatch: Pointer to selector function 895 * @data: User data 896 * 897 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled. 898 * The argument @error must be a negative error value. 899 */ 900 unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error, 901 bool (*fnmatch)(const struct rpc_task *, 902 const void *), 903 const void *data) 904 { 905 struct rpc_task *task; 906 unsigned long count = 0; 907 908 if (list_empty(&clnt->cl_tasks)) 909 return 0; 910 /* 911 * Spin lock all_tasks to prevent changes... 912 */ 913 spin_lock(&clnt->cl_lock); 914 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 915 if (!RPC_IS_ACTIVATED(task)) 916 continue; 917 if (!fnmatch(task, data)) 918 continue; 919 rpc_task_try_cancel(task, error); 920 count++; 921 } 922 spin_unlock(&clnt->cl_lock); 923 return count; 924 } 925 EXPORT_SYMBOL_GPL(rpc_cancel_tasks); 926 927 static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt, 928 struct rpc_xprt *xprt, void *dummy) 929 { 930 if (xprt_connected(xprt)) 931 xprt_force_disconnect(xprt); 932 return 0; 933 } 934 935 void rpc_clnt_disconnect(struct rpc_clnt *clnt) 936 { 937 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL); 938 } 939 EXPORT_SYMBOL_GPL(rpc_clnt_disconnect); 940 941 /* 942 * Properly shut down an RPC client, terminating all outstanding 943 * requests. 944 */ 945 void rpc_shutdown_client(struct rpc_clnt *clnt) 946 { 947 might_sleep(); 948 949 trace_rpc_clnt_shutdown(clnt); 950 951 while (!list_empty(&clnt->cl_tasks)) { 952 rpc_killall_tasks(clnt); 953 wait_event_timeout(destroy_wait, 954 list_empty(&clnt->cl_tasks), 1*HZ); 955 } 956 957 rpc_release_client(clnt); 958 } 959 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 960 961 /* 962 * Free an RPC client 963 */ 964 static void rpc_free_client_work(struct work_struct *work) 965 { 966 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work); 967 968 trace_rpc_clnt_free(clnt); 969 970 /* These might block on processes that might allocate memory, 971 * so they cannot be called in rpciod, so they are handled separately 972 * here. 973 */ 974 rpc_sysfs_client_destroy(clnt); 975 rpc_clnt_debugfs_unregister(clnt); 976 rpc_free_clid(clnt); 977 rpc_clnt_remove_pipedir(clnt); 978 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 979 980 kfree(clnt); 981 rpciod_down(); 982 } 983 static struct rpc_clnt * 984 rpc_free_client(struct rpc_clnt *clnt) 985 { 986 struct rpc_clnt *parent = NULL; 987 988 trace_rpc_clnt_release(clnt); 989 if (clnt->cl_parent != clnt) 990 parent = clnt->cl_parent; 991 rpc_unregister_client(clnt); 992 rpc_free_iostats(clnt->cl_metrics); 993 clnt->cl_metrics = NULL; 994 xprt_iter_destroy(&clnt->cl_xpi); 995 put_cred(clnt->cl_cred); 996 997 INIT_WORK(&clnt->cl_work, rpc_free_client_work); 998 schedule_work(&clnt->cl_work); 999 return parent; 1000 } 1001 1002 /* 1003 * Free an RPC client 1004 */ 1005 static struct rpc_clnt * 1006 rpc_free_auth(struct rpc_clnt *clnt) 1007 { 1008 /* 1009 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 1010 * release remaining GSS contexts. This mechanism ensures 1011 * that it can do so safely. 1012 */ 1013 if (clnt->cl_auth != NULL) { 1014 rpcauth_release(clnt->cl_auth); 1015 clnt->cl_auth = NULL; 1016 } 1017 if (refcount_dec_and_test(&clnt->cl_count)) 1018 return rpc_free_client(clnt); 1019 return NULL; 1020 } 1021 1022 /* 1023 * Release reference to the RPC client 1024 */ 1025 void 1026 rpc_release_client(struct rpc_clnt *clnt) 1027 { 1028 do { 1029 if (list_empty(&clnt->cl_tasks)) 1030 wake_up(&destroy_wait); 1031 if (refcount_dec_not_one(&clnt->cl_count)) 1032 break; 1033 clnt = rpc_free_auth(clnt); 1034 } while (clnt != NULL); 1035 } 1036 EXPORT_SYMBOL_GPL(rpc_release_client); 1037 1038 /** 1039 * rpc_bind_new_program - bind a new RPC program to an existing client 1040 * @old: old rpc_client 1041 * @program: rpc program to set 1042 * @vers: rpc program version 1043 * 1044 * Clones the rpc client and sets up a new RPC program. This is mainly 1045 * of use for enabling different RPC programs to share the same transport. 1046 * The Sun NFSv2/v3 ACL protocol can do this. 1047 */ 1048 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 1049 const struct rpc_program *program, 1050 u32 vers) 1051 { 1052 struct rpc_create_args args = { 1053 .program = program, 1054 .prognumber = program->number, 1055 .version = vers, 1056 .authflavor = old->cl_auth->au_flavor, 1057 .cred = old->cl_cred, 1058 .stats = old->cl_stats, 1059 .timeout = old->cl_timeout, 1060 }; 1061 struct rpc_clnt *clnt; 1062 int err; 1063 1064 clnt = __rpc_clone_client(&args, old); 1065 if (IS_ERR(clnt)) 1066 goto out; 1067 err = rpc_ping(clnt); 1068 if (err != 0) { 1069 rpc_shutdown_client(clnt); 1070 clnt = ERR_PTR(err); 1071 } 1072 out: 1073 return clnt; 1074 } 1075 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 1076 1077 struct rpc_xprt * 1078 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1079 { 1080 struct rpc_xprt_switch *xps; 1081 1082 if (!xprt) 1083 return NULL; 1084 rcu_read_lock(); 1085 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1086 atomic_long_inc(&xps->xps_queuelen); 1087 rcu_read_unlock(); 1088 atomic_long_inc(&xprt->queuelen); 1089 1090 return xprt; 1091 } 1092 1093 static void 1094 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 1095 { 1096 struct rpc_xprt_switch *xps; 1097 1098 atomic_long_dec(&xprt->queuelen); 1099 rcu_read_lock(); 1100 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 1101 atomic_long_dec(&xps->xps_queuelen); 1102 rcu_read_unlock(); 1103 1104 xprt_put(xprt); 1105 } 1106 1107 void rpc_task_release_transport(struct rpc_task *task) 1108 { 1109 struct rpc_xprt *xprt = task->tk_xprt; 1110 1111 if (xprt) { 1112 task->tk_xprt = NULL; 1113 if (task->tk_client) 1114 rpc_task_release_xprt(task->tk_client, xprt); 1115 else 1116 xprt_put(xprt); 1117 } 1118 } 1119 EXPORT_SYMBOL_GPL(rpc_task_release_transport); 1120 1121 void rpc_task_release_client(struct rpc_task *task) 1122 { 1123 struct rpc_clnt *clnt = task->tk_client; 1124 1125 rpc_task_release_transport(task); 1126 if (clnt != NULL) { 1127 /* Remove from client task list */ 1128 spin_lock(&clnt->cl_lock); 1129 list_del(&task->tk_task); 1130 spin_unlock(&clnt->cl_lock); 1131 task->tk_client = NULL; 1132 1133 rpc_release_client(clnt); 1134 } 1135 } 1136 1137 static struct rpc_xprt * 1138 rpc_task_get_first_xprt(struct rpc_clnt *clnt) 1139 { 1140 struct rpc_xprt *xprt; 1141 1142 rcu_read_lock(); 1143 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 1144 rcu_read_unlock(); 1145 return rpc_task_get_xprt(clnt, xprt); 1146 } 1147 1148 static struct rpc_xprt * 1149 rpc_task_get_next_xprt(struct rpc_clnt *clnt) 1150 { 1151 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi)); 1152 } 1153 1154 static 1155 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt) 1156 { 1157 if (task->tk_xprt) { 1158 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) && 1159 (task->tk_flags & RPC_TASK_MOVEABLE))) 1160 return; 1161 xprt_release(task); 1162 xprt_put(task->tk_xprt); 1163 } 1164 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) 1165 task->tk_xprt = rpc_task_get_first_xprt(clnt); 1166 else 1167 task->tk_xprt = rpc_task_get_next_xprt(clnt); 1168 } 1169 1170 static 1171 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 1172 { 1173 rpc_task_set_transport(task, clnt); 1174 task->tk_client = clnt; 1175 refcount_inc(&clnt->cl_count); 1176 if (clnt->cl_softrtry) 1177 task->tk_flags |= RPC_TASK_SOFT; 1178 if (clnt->cl_softerr) 1179 task->tk_flags |= RPC_TASK_TIMEOUT; 1180 if (clnt->cl_noretranstimeo) 1181 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1182 /* Add to the client's list of all tasks */ 1183 spin_lock(&clnt->cl_lock); 1184 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1185 spin_unlock(&clnt->cl_lock); 1186 } 1187 1188 static void 1189 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1190 { 1191 if (msg != NULL) { 1192 task->tk_msg.rpc_proc = msg->rpc_proc; 1193 task->tk_msg.rpc_argp = msg->rpc_argp; 1194 task->tk_msg.rpc_resp = msg->rpc_resp; 1195 task->tk_msg.rpc_cred = msg->rpc_cred; 1196 if (!(task->tk_flags & RPC_TASK_CRED_NOREF)) 1197 get_cred(task->tk_msg.rpc_cred); 1198 } 1199 } 1200 1201 /* 1202 * Default callback for async RPC calls 1203 */ 1204 static void 1205 rpc_default_callback(struct rpc_task *task, void *data) 1206 { 1207 } 1208 1209 static const struct rpc_call_ops rpc_default_ops = { 1210 .rpc_call_done = rpc_default_callback, 1211 }; 1212 1213 /** 1214 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1215 * @task_setup_data: pointer to task initialisation data 1216 */ 1217 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1218 { 1219 struct rpc_task *task; 1220 1221 task = rpc_new_task(task_setup_data); 1222 if (IS_ERR(task)) 1223 return task; 1224 1225 if (!RPC_IS_ASYNC(task)) 1226 task->tk_flags |= RPC_TASK_CRED_NOREF; 1227 1228 rpc_task_set_client(task, task_setup_data->rpc_client); 1229 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1230 1231 if (task->tk_action == NULL) 1232 rpc_call_start(task); 1233 1234 atomic_inc(&task->tk_count); 1235 rpc_execute(task); 1236 return task; 1237 } 1238 EXPORT_SYMBOL_GPL(rpc_run_task); 1239 1240 /** 1241 * rpc_call_sync - Perform a synchronous RPC call 1242 * @clnt: pointer to RPC client 1243 * @msg: RPC call parameters 1244 * @flags: RPC call flags 1245 */ 1246 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1247 { 1248 struct rpc_task *task; 1249 struct rpc_task_setup task_setup_data = { 1250 .rpc_client = clnt, 1251 .rpc_message = msg, 1252 .callback_ops = &rpc_default_ops, 1253 .flags = flags, 1254 }; 1255 int status; 1256 1257 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1258 if (flags & RPC_TASK_ASYNC) { 1259 rpc_release_calldata(task_setup_data.callback_ops, 1260 task_setup_data.callback_data); 1261 return -EINVAL; 1262 } 1263 1264 task = rpc_run_task(&task_setup_data); 1265 if (IS_ERR(task)) 1266 return PTR_ERR(task); 1267 status = task->tk_status; 1268 rpc_put_task(task); 1269 return status; 1270 } 1271 EXPORT_SYMBOL_GPL(rpc_call_sync); 1272 1273 /** 1274 * rpc_call_async - Perform an asynchronous RPC call 1275 * @clnt: pointer to RPC client 1276 * @msg: RPC call parameters 1277 * @flags: RPC call flags 1278 * @tk_ops: RPC call ops 1279 * @data: user call data 1280 */ 1281 int 1282 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1283 const struct rpc_call_ops *tk_ops, void *data) 1284 { 1285 struct rpc_task *task; 1286 struct rpc_task_setup task_setup_data = { 1287 .rpc_client = clnt, 1288 .rpc_message = msg, 1289 .callback_ops = tk_ops, 1290 .callback_data = data, 1291 .flags = flags|RPC_TASK_ASYNC, 1292 }; 1293 1294 task = rpc_run_task(&task_setup_data); 1295 if (IS_ERR(task)) 1296 return PTR_ERR(task); 1297 rpc_put_task(task); 1298 return 0; 1299 } 1300 EXPORT_SYMBOL_GPL(rpc_call_async); 1301 1302 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1303 static void call_bc_encode(struct rpc_task *task); 1304 1305 /** 1306 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1307 * rpc_execute against it 1308 * @req: RPC request 1309 */ 1310 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) 1311 { 1312 struct rpc_task *task; 1313 struct rpc_task_setup task_setup_data = { 1314 .callback_ops = &rpc_default_ops, 1315 .flags = RPC_TASK_SOFTCONN | 1316 RPC_TASK_NO_RETRANS_TIMEOUT, 1317 }; 1318 1319 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1320 /* 1321 * Create an rpc_task to send the data 1322 */ 1323 task = rpc_new_task(&task_setup_data); 1324 if (IS_ERR(task)) { 1325 xprt_free_bc_request(req); 1326 return task; 1327 } 1328 1329 xprt_init_bc_request(req, task); 1330 1331 task->tk_action = call_bc_encode; 1332 atomic_inc(&task->tk_count); 1333 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1334 rpc_execute(task); 1335 1336 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1337 return task; 1338 } 1339 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1340 1341 /** 1342 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages 1343 * @req: RPC request to prepare 1344 * @pages: vector of struct page pointers 1345 * @base: offset in first page where receive should start, in bytes 1346 * @len: expected size of the upper layer data payload, in bytes 1347 * @hdrsize: expected size of upper layer reply header, in XDR words 1348 * 1349 */ 1350 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages, 1351 unsigned int base, unsigned int len, 1352 unsigned int hdrsize) 1353 { 1354 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign; 1355 1356 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len); 1357 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf); 1358 } 1359 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages); 1360 1361 void 1362 rpc_call_start(struct rpc_task *task) 1363 { 1364 task->tk_action = call_start; 1365 } 1366 EXPORT_SYMBOL_GPL(rpc_call_start); 1367 1368 /** 1369 * rpc_peeraddr - extract remote peer address from clnt's xprt 1370 * @clnt: RPC client structure 1371 * @buf: target buffer 1372 * @bufsize: length of target buffer 1373 * 1374 * Returns the number of bytes that are actually in the stored address. 1375 */ 1376 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1377 { 1378 size_t bytes; 1379 struct rpc_xprt *xprt; 1380 1381 rcu_read_lock(); 1382 xprt = rcu_dereference(clnt->cl_xprt); 1383 1384 bytes = xprt->addrlen; 1385 if (bytes > bufsize) 1386 bytes = bufsize; 1387 memcpy(buf, &xprt->addr, bytes); 1388 rcu_read_unlock(); 1389 1390 return bytes; 1391 } 1392 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1393 1394 /** 1395 * rpc_peeraddr2str - return remote peer address in printable format 1396 * @clnt: RPC client structure 1397 * @format: address format 1398 * 1399 * NB: the lifetime of the memory referenced by the returned pointer is 1400 * the same as the rpc_xprt itself. As long as the caller uses this 1401 * pointer, it must hold the RCU read lock. 1402 */ 1403 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1404 enum rpc_display_format_t format) 1405 { 1406 struct rpc_xprt *xprt; 1407 1408 xprt = rcu_dereference(clnt->cl_xprt); 1409 1410 if (xprt->address_strings[format] != NULL) 1411 return xprt->address_strings[format]; 1412 else 1413 return "unprintable"; 1414 } 1415 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1416 1417 static const struct sockaddr_in rpc_inaddr_loopback = { 1418 .sin_family = AF_INET, 1419 .sin_addr.s_addr = htonl(INADDR_ANY), 1420 }; 1421 1422 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1423 .sin6_family = AF_INET6, 1424 .sin6_addr = IN6ADDR_ANY_INIT, 1425 }; 1426 1427 /* 1428 * Try a getsockname() on a connected datagram socket. Using a 1429 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1430 * This conserves the ephemeral port number space. 1431 * 1432 * Returns zero and fills in "buf" if successful; otherwise, a 1433 * negative errno is returned. 1434 */ 1435 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1436 struct sockaddr *buf) 1437 { 1438 struct socket *sock; 1439 int err; 1440 1441 err = __sock_create(net, sap->sa_family, 1442 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1443 if (err < 0) { 1444 dprintk("RPC: can't create UDP socket (%d)\n", err); 1445 goto out; 1446 } 1447 1448 switch (sap->sa_family) { 1449 case AF_INET: 1450 err = kernel_bind(sock, 1451 (struct sockaddr *)&rpc_inaddr_loopback, 1452 sizeof(rpc_inaddr_loopback)); 1453 break; 1454 case AF_INET6: 1455 err = kernel_bind(sock, 1456 (struct sockaddr *)&rpc_in6addr_loopback, 1457 sizeof(rpc_in6addr_loopback)); 1458 break; 1459 default: 1460 err = -EAFNOSUPPORT; 1461 goto out_release; 1462 } 1463 if (err < 0) { 1464 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1465 goto out_release; 1466 } 1467 1468 err = kernel_connect(sock, sap, salen, 0); 1469 if (err < 0) { 1470 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1471 goto out_release; 1472 } 1473 1474 err = kernel_getsockname(sock, buf); 1475 if (err < 0) { 1476 dprintk("RPC: getsockname failed (%d)\n", err); 1477 goto out_release; 1478 } 1479 1480 err = 0; 1481 if (buf->sa_family == AF_INET6) { 1482 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1483 sin6->sin6_scope_id = 0; 1484 } 1485 dprintk("RPC: %s succeeded\n", __func__); 1486 1487 out_release: 1488 sock_release(sock); 1489 out: 1490 return err; 1491 } 1492 1493 /* 1494 * Scraping a connected socket failed, so we don't have a useable 1495 * local address. Fallback: generate an address that will prevent 1496 * the server from calling us back. 1497 * 1498 * Returns zero and fills in "buf" if successful; otherwise, a 1499 * negative errno is returned. 1500 */ 1501 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1502 { 1503 switch (family) { 1504 case AF_INET: 1505 if (buflen < sizeof(rpc_inaddr_loopback)) 1506 return -EINVAL; 1507 memcpy(buf, &rpc_inaddr_loopback, 1508 sizeof(rpc_inaddr_loopback)); 1509 break; 1510 case AF_INET6: 1511 if (buflen < sizeof(rpc_in6addr_loopback)) 1512 return -EINVAL; 1513 memcpy(buf, &rpc_in6addr_loopback, 1514 sizeof(rpc_in6addr_loopback)); 1515 break; 1516 default: 1517 dprintk("RPC: %s: address family not supported\n", 1518 __func__); 1519 return -EAFNOSUPPORT; 1520 } 1521 dprintk("RPC: %s: succeeded\n", __func__); 1522 return 0; 1523 } 1524 1525 /** 1526 * rpc_localaddr - discover local endpoint address for an RPC client 1527 * @clnt: RPC client structure 1528 * @buf: target buffer 1529 * @buflen: size of target buffer, in bytes 1530 * 1531 * Returns zero and fills in "buf" and "buflen" if successful; 1532 * otherwise, a negative errno is returned. 1533 * 1534 * This works even if the underlying transport is not currently connected, 1535 * or if the upper layer never previously provided a source address. 1536 * 1537 * The result of this function call is transient: multiple calls in 1538 * succession may give different results, depending on how local 1539 * networking configuration changes over time. 1540 */ 1541 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1542 { 1543 struct sockaddr_storage address; 1544 struct sockaddr *sap = (struct sockaddr *)&address; 1545 struct rpc_xprt *xprt; 1546 struct net *net; 1547 size_t salen; 1548 int err; 1549 1550 rcu_read_lock(); 1551 xprt = rcu_dereference(clnt->cl_xprt); 1552 salen = xprt->addrlen; 1553 memcpy(sap, &xprt->addr, salen); 1554 net = get_net(xprt->xprt_net); 1555 rcu_read_unlock(); 1556 1557 rpc_set_port(sap, 0); 1558 err = rpc_sockname(net, sap, salen, buf); 1559 put_net(net); 1560 if (err != 0) 1561 /* Couldn't discover local address, return ANYADDR */ 1562 return rpc_anyaddr(sap->sa_family, buf, buflen); 1563 return 0; 1564 } 1565 EXPORT_SYMBOL_GPL(rpc_localaddr); 1566 1567 void 1568 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1569 { 1570 struct rpc_xprt *xprt; 1571 1572 rcu_read_lock(); 1573 xprt = rcu_dereference(clnt->cl_xprt); 1574 if (xprt->ops->set_buffer_size) 1575 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1576 rcu_read_unlock(); 1577 } 1578 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1579 1580 /** 1581 * rpc_net_ns - Get the network namespace for this RPC client 1582 * @clnt: RPC client to query 1583 * 1584 */ 1585 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1586 { 1587 struct net *ret; 1588 1589 rcu_read_lock(); 1590 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1591 rcu_read_unlock(); 1592 return ret; 1593 } 1594 EXPORT_SYMBOL_GPL(rpc_net_ns); 1595 1596 /** 1597 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1598 * @clnt: RPC client to query 1599 * 1600 * For stream transports, this is one RPC record fragment (see RFC 1601 * 1831), as we don't support multi-record requests yet. For datagram 1602 * transports, this is the size of an IP packet minus the IP, UDP, and 1603 * RPC header sizes. 1604 */ 1605 size_t rpc_max_payload(struct rpc_clnt *clnt) 1606 { 1607 size_t ret; 1608 1609 rcu_read_lock(); 1610 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1611 rcu_read_unlock(); 1612 return ret; 1613 } 1614 EXPORT_SYMBOL_GPL(rpc_max_payload); 1615 1616 /** 1617 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1618 * @clnt: RPC client to query 1619 */ 1620 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1621 { 1622 struct rpc_xprt *xprt; 1623 size_t ret; 1624 1625 rcu_read_lock(); 1626 xprt = rcu_dereference(clnt->cl_xprt); 1627 ret = xprt->ops->bc_maxpayload(xprt); 1628 rcu_read_unlock(); 1629 return ret; 1630 } 1631 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1632 1633 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt) 1634 { 1635 struct rpc_xprt *xprt; 1636 unsigned int ret; 1637 1638 rcu_read_lock(); 1639 xprt = rcu_dereference(clnt->cl_xprt); 1640 ret = xprt->ops->bc_num_slots(xprt); 1641 rcu_read_unlock(); 1642 return ret; 1643 } 1644 EXPORT_SYMBOL_GPL(rpc_num_bc_slots); 1645 1646 /** 1647 * rpc_force_rebind - force transport to check that remote port is unchanged 1648 * @clnt: client to rebind 1649 * 1650 */ 1651 void rpc_force_rebind(struct rpc_clnt *clnt) 1652 { 1653 if (clnt->cl_autobind) { 1654 rcu_read_lock(); 1655 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1656 rcu_read_unlock(); 1657 } 1658 } 1659 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1660 1661 static int 1662 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *)) 1663 { 1664 task->tk_status = 0; 1665 task->tk_rpc_status = 0; 1666 task->tk_action = action; 1667 return 1; 1668 } 1669 1670 /* 1671 * Restart an (async) RPC call. Usually called from within the 1672 * exit handler. 1673 */ 1674 int 1675 rpc_restart_call(struct rpc_task *task) 1676 { 1677 return __rpc_restart_call(task, call_start); 1678 } 1679 EXPORT_SYMBOL_GPL(rpc_restart_call); 1680 1681 /* 1682 * Restart an (async) RPC call from the call_prepare state. 1683 * Usually called from within the exit handler. 1684 */ 1685 int 1686 rpc_restart_call_prepare(struct rpc_task *task) 1687 { 1688 if (task->tk_ops->rpc_call_prepare != NULL) 1689 return __rpc_restart_call(task, rpc_prepare_task); 1690 return rpc_restart_call(task); 1691 } 1692 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1693 1694 const char 1695 *rpc_proc_name(const struct rpc_task *task) 1696 { 1697 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1698 1699 if (proc) { 1700 if (proc->p_name) 1701 return proc->p_name; 1702 else 1703 return "NULL"; 1704 } else 1705 return "no proc"; 1706 } 1707 1708 static void 1709 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status) 1710 { 1711 trace_rpc_call_rpcerror(task, tk_status, rpc_status); 1712 rpc_task_set_rpc_status(task, rpc_status); 1713 rpc_exit(task, tk_status); 1714 } 1715 1716 static void 1717 rpc_call_rpcerror(struct rpc_task *task, int status) 1718 { 1719 __rpc_call_rpcerror(task, status, status); 1720 } 1721 1722 /* 1723 * 0. Initial state 1724 * 1725 * Other FSM states can be visited zero or more times, but 1726 * this state is visited exactly once for each RPC. 1727 */ 1728 static void 1729 call_start(struct rpc_task *task) 1730 { 1731 struct rpc_clnt *clnt = task->tk_client; 1732 int idx = task->tk_msg.rpc_proc->p_statidx; 1733 1734 trace_rpc_request(task); 1735 1736 if (task->tk_client->cl_shutdown) { 1737 rpc_call_rpcerror(task, -EIO); 1738 return; 1739 } 1740 1741 /* Increment call count (version might not be valid for ping) */ 1742 if (clnt->cl_program->version[clnt->cl_vers]) 1743 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++; 1744 clnt->cl_stats->rpccnt++; 1745 task->tk_action = call_reserve; 1746 rpc_task_set_transport(task, clnt); 1747 } 1748 1749 /* 1750 * 1. Reserve an RPC call slot 1751 */ 1752 static void 1753 call_reserve(struct rpc_task *task) 1754 { 1755 task->tk_status = 0; 1756 task->tk_action = call_reserveresult; 1757 xprt_reserve(task); 1758 } 1759 1760 static void call_retry_reserve(struct rpc_task *task); 1761 1762 /* 1763 * 1b. Grok the result of xprt_reserve() 1764 */ 1765 static void 1766 call_reserveresult(struct rpc_task *task) 1767 { 1768 int status = task->tk_status; 1769 1770 /* 1771 * After a call to xprt_reserve(), we must have either 1772 * a request slot or else an error status. 1773 */ 1774 task->tk_status = 0; 1775 if (status >= 0) { 1776 if (task->tk_rqstp) { 1777 task->tk_action = call_refresh; 1778 return; 1779 } 1780 1781 rpc_call_rpcerror(task, -EIO); 1782 return; 1783 } 1784 1785 switch (status) { 1786 case -ENOMEM: 1787 rpc_delay(task, HZ >> 2); 1788 fallthrough; 1789 case -EAGAIN: /* woken up; retry */ 1790 task->tk_action = call_retry_reserve; 1791 return; 1792 default: 1793 rpc_call_rpcerror(task, status); 1794 } 1795 } 1796 1797 /* 1798 * 1c. Retry reserving an RPC call slot 1799 */ 1800 static void 1801 call_retry_reserve(struct rpc_task *task) 1802 { 1803 task->tk_status = 0; 1804 task->tk_action = call_reserveresult; 1805 xprt_retry_reserve(task); 1806 } 1807 1808 /* 1809 * 2. Bind and/or refresh the credentials 1810 */ 1811 static void 1812 call_refresh(struct rpc_task *task) 1813 { 1814 task->tk_action = call_refreshresult; 1815 task->tk_status = 0; 1816 task->tk_client->cl_stats->rpcauthrefresh++; 1817 rpcauth_refreshcred(task); 1818 } 1819 1820 /* 1821 * 2a. Process the results of a credential refresh 1822 */ 1823 static void 1824 call_refreshresult(struct rpc_task *task) 1825 { 1826 int status = task->tk_status; 1827 1828 task->tk_status = 0; 1829 task->tk_action = call_refresh; 1830 switch (status) { 1831 case 0: 1832 if (rpcauth_uptodatecred(task)) { 1833 task->tk_action = call_allocate; 1834 return; 1835 } 1836 /* Use rate-limiting and a max number of retries if refresh 1837 * had status 0 but failed to update the cred. 1838 */ 1839 fallthrough; 1840 case -ETIMEDOUT: 1841 rpc_delay(task, 3*HZ); 1842 fallthrough; 1843 case -EAGAIN: 1844 status = -EACCES; 1845 fallthrough; 1846 case -EKEYEXPIRED: 1847 if (!task->tk_cred_retry) 1848 break; 1849 task->tk_cred_retry--; 1850 trace_rpc_retry_refresh_status(task); 1851 return; 1852 case -ENOMEM: 1853 rpc_delay(task, HZ >> 4); 1854 return; 1855 } 1856 trace_rpc_refresh_status(task); 1857 rpc_call_rpcerror(task, status); 1858 } 1859 1860 /* 1861 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1862 * (Note: buffer memory is freed in xprt_release). 1863 */ 1864 static void 1865 call_allocate(struct rpc_task *task) 1866 { 1867 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth; 1868 struct rpc_rqst *req = task->tk_rqstp; 1869 struct rpc_xprt *xprt = req->rq_xprt; 1870 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1871 int status; 1872 1873 task->tk_status = 0; 1874 task->tk_action = call_encode; 1875 1876 if (req->rq_buffer) 1877 return; 1878 1879 if (proc->p_proc != 0) { 1880 BUG_ON(proc->p_arglen == 0); 1881 if (proc->p_decode != NULL) 1882 BUG_ON(proc->p_replen == 0); 1883 } 1884 1885 /* 1886 * Calculate the size (in quads) of the RPC call 1887 * and reply headers, and convert both values 1888 * to byte sizes. 1889 */ 1890 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) + 1891 proc->p_arglen; 1892 req->rq_callsize <<= 2; 1893 /* 1894 * Note: the reply buffer must at minimum allocate enough space 1895 * for the 'struct accepted_reply' from RFC5531. 1896 */ 1897 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \ 1898 max_t(size_t, proc->p_replen, 2); 1899 req->rq_rcvsize <<= 2; 1900 1901 status = xprt->ops->buf_alloc(task); 1902 trace_rpc_buf_alloc(task, status); 1903 if (status == 0) 1904 return; 1905 if (status != -ENOMEM) { 1906 rpc_call_rpcerror(task, status); 1907 return; 1908 } 1909 1910 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1911 task->tk_action = call_allocate; 1912 rpc_delay(task, HZ>>4); 1913 return; 1914 } 1915 1916 rpc_call_rpcerror(task, -ERESTARTSYS); 1917 } 1918 1919 static int 1920 rpc_task_need_encode(struct rpc_task *task) 1921 { 1922 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 && 1923 (!(task->tk_flags & RPC_TASK_SENT) || 1924 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) || 1925 xprt_request_need_retransmit(task)); 1926 } 1927 1928 static void 1929 rpc_xdr_encode(struct rpc_task *task) 1930 { 1931 struct rpc_rqst *req = task->tk_rqstp; 1932 struct xdr_stream xdr; 1933 1934 xdr_buf_init(&req->rq_snd_buf, 1935 req->rq_buffer, 1936 req->rq_callsize); 1937 xdr_buf_init(&req->rq_rcv_buf, 1938 req->rq_rbuffer, 1939 req->rq_rcvsize); 1940 1941 req->rq_reply_bytes_recvd = 0; 1942 req->rq_snd_buf.head[0].iov_len = 0; 1943 xdr_init_encode(&xdr, &req->rq_snd_buf, 1944 req->rq_snd_buf.head[0].iov_base, req); 1945 if (rpc_encode_header(task, &xdr)) 1946 return; 1947 1948 task->tk_status = rpcauth_wrap_req(task, &xdr); 1949 } 1950 1951 /* 1952 * 3. Encode arguments of an RPC call 1953 */ 1954 static void 1955 call_encode(struct rpc_task *task) 1956 { 1957 if (!rpc_task_need_encode(task)) 1958 goto out; 1959 1960 /* Dequeue task from the receive queue while we're encoding */ 1961 xprt_request_dequeue_xprt(task); 1962 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1963 rpc_xdr_encode(task); 1964 /* Add task to reply queue before transmission to avoid races */ 1965 if (task->tk_status == 0 && rpc_reply_expected(task)) 1966 task->tk_status = xprt_request_enqueue_receive(task); 1967 /* Did the encode result in an error condition? */ 1968 if (task->tk_status != 0) { 1969 /* Was the error nonfatal? */ 1970 switch (task->tk_status) { 1971 case -EAGAIN: 1972 case -ENOMEM: 1973 rpc_delay(task, HZ >> 4); 1974 break; 1975 case -EKEYEXPIRED: 1976 if (!task->tk_cred_retry) { 1977 rpc_call_rpcerror(task, task->tk_status); 1978 } else { 1979 task->tk_action = call_refresh; 1980 task->tk_cred_retry--; 1981 trace_rpc_retry_refresh_status(task); 1982 } 1983 break; 1984 default: 1985 rpc_call_rpcerror(task, task->tk_status); 1986 } 1987 return; 1988 } 1989 1990 xprt_request_enqueue_transmit(task); 1991 out: 1992 task->tk_action = call_transmit; 1993 /* Check that the connection is OK */ 1994 if (!xprt_bound(task->tk_xprt)) 1995 task->tk_action = call_bind; 1996 else if (!xprt_connected(task->tk_xprt)) 1997 task->tk_action = call_connect; 1998 } 1999 2000 /* 2001 * Helpers to check if the task was already transmitted, and 2002 * to take action when that is the case. 2003 */ 2004 static bool 2005 rpc_task_transmitted(struct rpc_task *task) 2006 { 2007 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate); 2008 } 2009 2010 static void 2011 rpc_task_handle_transmitted(struct rpc_task *task) 2012 { 2013 xprt_end_transmit(task); 2014 task->tk_action = call_transmit_status; 2015 } 2016 2017 /* 2018 * 4. Get the server port number if not yet set 2019 */ 2020 static void 2021 call_bind(struct rpc_task *task) 2022 { 2023 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2024 2025 if (rpc_task_transmitted(task)) { 2026 rpc_task_handle_transmitted(task); 2027 return; 2028 } 2029 2030 if (xprt_bound(xprt)) { 2031 task->tk_action = call_connect; 2032 return; 2033 } 2034 2035 task->tk_action = call_bind_status; 2036 if (!xprt_prepare_transmit(task)) 2037 return; 2038 2039 xprt->ops->rpcbind(task); 2040 } 2041 2042 /* 2043 * 4a. Sort out bind result 2044 */ 2045 static void 2046 call_bind_status(struct rpc_task *task) 2047 { 2048 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2049 int status = -EIO; 2050 2051 if (rpc_task_transmitted(task)) { 2052 rpc_task_handle_transmitted(task); 2053 return; 2054 } 2055 2056 if (task->tk_status >= 0) 2057 goto out_next; 2058 if (xprt_bound(xprt)) { 2059 task->tk_status = 0; 2060 goto out_next; 2061 } 2062 2063 switch (task->tk_status) { 2064 case -ENOMEM: 2065 rpc_delay(task, HZ >> 2); 2066 goto retry_timeout; 2067 case -EACCES: 2068 trace_rpcb_prog_unavail_err(task); 2069 /* fail immediately if this is an RPC ping */ 2070 if (task->tk_msg.rpc_proc->p_proc == 0) { 2071 status = -EOPNOTSUPP; 2072 break; 2073 } 2074 rpc_delay(task, 3*HZ); 2075 goto retry_timeout; 2076 case -ENOBUFS: 2077 rpc_delay(task, HZ >> 2); 2078 goto retry_timeout; 2079 case -EAGAIN: 2080 goto retry_timeout; 2081 case -ETIMEDOUT: 2082 trace_rpcb_timeout_err(task); 2083 goto retry_timeout; 2084 case -EPFNOSUPPORT: 2085 /* server doesn't support any rpcbind version we know of */ 2086 trace_rpcb_bind_version_err(task); 2087 break; 2088 case -EPROTONOSUPPORT: 2089 trace_rpcb_bind_version_err(task); 2090 goto retry_timeout; 2091 case -ECONNREFUSED: /* connection problems */ 2092 case -ECONNRESET: 2093 case -ECONNABORTED: 2094 case -ENOTCONN: 2095 case -EHOSTDOWN: 2096 case -ENETDOWN: 2097 case -EHOSTUNREACH: 2098 case -ENETUNREACH: 2099 case -EPIPE: 2100 trace_rpcb_unreachable_err(task); 2101 if (!RPC_IS_SOFTCONN(task)) { 2102 rpc_delay(task, 5*HZ); 2103 goto retry_timeout; 2104 } 2105 status = task->tk_status; 2106 break; 2107 default: 2108 trace_rpcb_unrecognized_err(task); 2109 } 2110 2111 rpc_call_rpcerror(task, status); 2112 return; 2113 out_next: 2114 task->tk_action = call_connect; 2115 return; 2116 retry_timeout: 2117 task->tk_status = 0; 2118 task->tk_action = call_bind; 2119 rpc_check_timeout(task); 2120 } 2121 2122 /* 2123 * 4b. Connect to the RPC server 2124 */ 2125 static void 2126 call_connect(struct rpc_task *task) 2127 { 2128 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2129 2130 if (rpc_task_transmitted(task)) { 2131 rpc_task_handle_transmitted(task); 2132 return; 2133 } 2134 2135 if (xprt_connected(xprt)) { 2136 task->tk_action = call_transmit; 2137 return; 2138 } 2139 2140 task->tk_action = call_connect_status; 2141 if (task->tk_status < 0) 2142 return; 2143 if (task->tk_flags & RPC_TASK_NOCONNECT) { 2144 rpc_call_rpcerror(task, -ENOTCONN); 2145 return; 2146 } 2147 if (!xprt_prepare_transmit(task)) 2148 return; 2149 xprt_connect(task); 2150 } 2151 2152 /* 2153 * 4c. Sort out connect result 2154 */ 2155 static void 2156 call_connect_status(struct rpc_task *task) 2157 { 2158 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 2159 struct rpc_clnt *clnt = task->tk_client; 2160 int status = task->tk_status; 2161 2162 if (rpc_task_transmitted(task)) { 2163 rpc_task_handle_transmitted(task); 2164 return; 2165 } 2166 2167 trace_rpc_connect_status(task); 2168 2169 if (task->tk_status == 0) { 2170 clnt->cl_stats->netreconn++; 2171 goto out_next; 2172 } 2173 if (xprt_connected(xprt)) { 2174 task->tk_status = 0; 2175 goto out_next; 2176 } 2177 2178 task->tk_status = 0; 2179 switch (status) { 2180 case -ECONNREFUSED: 2181 case -ECONNRESET: 2182 /* A positive refusal suggests a rebind is needed. */ 2183 if (RPC_IS_SOFTCONN(task)) 2184 break; 2185 if (clnt->cl_autobind) { 2186 rpc_force_rebind(clnt); 2187 goto out_retry; 2188 } 2189 fallthrough; 2190 case -ECONNABORTED: 2191 case -ENETDOWN: 2192 case -ENETUNREACH: 2193 case -EHOSTUNREACH: 2194 case -EPIPE: 2195 case -EPROTO: 2196 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt, 2197 task->tk_rqstp->rq_connect_cookie); 2198 if (RPC_IS_SOFTCONN(task)) 2199 break; 2200 /* retry with existing socket, after a delay */ 2201 rpc_delay(task, 3*HZ); 2202 fallthrough; 2203 case -EADDRINUSE: 2204 case -ENOTCONN: 2205 case -EAGAIN: 2206 case -ETIMEDOUT: 2207 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) && 2208 (task->tk_flags & RPC_TASK_MOVEABLE) && 2209 test_bit(XPRT_REMOVE, &xprt->state)) { 2210 struct rpc_xprt *saved = task->tk_xprt; 2211 struct rpc_xprt_switch *xps; 2212 2213 rcu_read_lock(); 2214 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2215 rcu_read_unlock(); 2216 if (xps->xps_nxprts > 1) { 2217 long value; 2218 2219 xprt_release(task); 2220 value = atomic_long_dec_return(&xprt->queuelen); 2221 if (value == 0) 2222 rpc_xprt_switch_remove_xprt(xps, saved, 2223 true); 2224 xprt_put(saved); 2225 task->tk_xprt = NULL; 2226 task->tk_action = call_start; 2227 } 2228 xprt_switch_put(xps); 2229 if (!task->tk_xprt) 2230 return; 2231 } 2232 goto out_retry; 2233 case -ENOBUFS: 2234 rpc_delay(task, HZ >> 2); 2235 goto out_retry; 2236 } 2237 rpc_call_rpcerror(task, status); 2238 return; 2239 out_next: 2240 task->tk_action = call_transmit; 2241 return; 2242 out_retry: 2243 /* Check for timeouts before looping back to call_bind */ 2244 task->tk_action = call_bind; 2245 rpc_check_timeout(task); 2246 } 2247 2248 /* 2249 * 5. Transmit the RPC request, and wait for reply 2250 */ 2251 static void 2252 call_transmit(struct rpc_task *task) 2253 { 2254 if (rpc_task_transmitted(task)) { 2255 rpc_task_handle_transmitted(task); 2256 return; 2257 } 2258 2259 task->tk_action = call_transmit_status; 2260 if (!xprt_prepare_transmit(task)) 2261 return; 2262 task->tk_status = 0; 2263 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2264 if (!xprt_connected(task->tk_xprt)) { 2265 task->tk_status = -ENOTCONN; 2266 return; 2267 } 2268 xprt_transmit(task); 2269 } 2270 xprt_end_transmit(task); 2271 } 2272 2273 /* 2274 * 5a. Handle cleanup after a transmission 2275 */ 2276 static void 2277 call_transmit_status(struct rpc_task *task) 2278 { 2279 task->tk_action = call_status; 2280 2281 /* 2282 * Common case: success. Force the compiler to put this 2283 * test first. 2284 */ 2285 if (rpc_task_transmitted(task)) { 2286 task->tk_status = 0; 2287 xprt_request_wait_receive(task); 2288 return; 2289 } 2290 2291 switch (task->tk_status) { 2292 default: 2293 break; 2294 case -EBADMSG: 2295 task->tk_status = 0; 2296 task->tk_action = call_encode; 2297 break; 2298 /* 2299 * Special cases: if we've been waiting on the 2300 * socket's write_space() callback, or if the 2301 * socket just returned a connection error, 2302 * then hold onto the transport lock. 2303 */ 2304 case -ENOMEM: 2305 case -ENOBUFS: 2306 rpc_delay(task, HZ>>2); 2307 fallthrough; 2308 case -EBADSLT: 2309 case -EAGAIN: 2310 task->tk_action = call_transmit; 2311 task->tk_status = 0; 2312 break; 2313 case -EHOSTDOWN: 2314 case -ENETDOWN: 2315 case -EHOSTUNREACH: 2316 case -ENETUNREACH: 2317 case -EPERM: 2318 break; 2319 case -ECONNREFUSED: 2320 if (RPC_IS_SOFTCONN(task)) { 2321 if (!task->tk_msg.rpc_proc->p_proc) 2322 trace_xprt_ping(task->tk_xprt, 2323 task->tk_status); 2324 rpc_call_rpcerror(task, task->tk_status); 2325 return; 2326 } 2327 fallthrough; 2328 case -ECONNRESET: 2329 case -ECONNABORTED: 2330 case -EADDRINUSE: 2331 case -ENOTCONN: 2332 case -EPIPE: 2333 task->tk_action = call_bind; 2334 task->tk_status = 0; 2335 break; 2336 } 2337 rpc_check_timeout(task); 2338 } 2339 2340 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2341 static void call_bc_transmit(struct rpc_task *task); 2342 static void call_bc_transmit_status(struct rpc_task *task); 2343 2344 static void 2345 call_bc_encode(struct rpc_task *task) 2346 { 2347 xprt_request_enqueue_transmit(task); 2348 task->tk_action = call_bc_transmit; 2349 } 2350 2351 /* 2352 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2353 * addition, disconnect on connectivity errors. 2354 */ 2355 static void 2356 call_bc_transmit(struct rpc_task *task) 2357 { 2358 task->tk_action = call_bc_transmit_status; 2359 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) { 2360 if (!xprt_prepare_transmit(task)) 2361 return; 2362 task->tk_status = 0; 2363 xprt_transmit(task); 2364 } 2365 xprt_end_transmit(task); 2366 } 2367 2368 static void 2369 call_bc_transmit_status(struct rpc_task *task) 2370 { 2371 struct rpc_rqst *req = task->tk_rqstp; 2372 2373 if (rpc_task_transmitted(task)) 2374 task->tk_status = 0; 2375 2376 switch (task->tk_status) { 2377 case 0: 2378 /* Success */ 2379 case -ENETDOWN: 2380 case -EHOSTDOWN: 2381 case -EHOSTUNREACH: 2382 case -ENETUNREACH: 2383 case -ECONNRESET: 2384 case -ECONNREFUSED: 2385 case -EADDRINUSE: 2386 case -ENOTCONN: 2387 case -EPIPE: 2388 break; 2389 case -ENOMEM: 2390 case -ENOBUFS: 2391 rpc_delay(task, HZ>>2); 2392 fallthrough; 2393 case -EBADSLT: 2394 case -EAGAIN: 2395 task->tk_status = 0; 2396 task->tk_action = call_bc_transmit; 2397 return; 2398 case -ETIMEDOUT: 2399 /* 2400 * Problem reaching the server. Disconnect and let the 2401 * forechannel reestablish the connection. The server will 2402 * have to retransmit the backchannel request and we'll 2403 * reprocess it. Since these ops are idempotent, there's no 2404 * need to cache our reply at this time. 2405 */ 2406 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2407 "error: %d\n", task->tk_status); 2408 xprt_conditional_disconnect(req->rq_xprt, 2409 req->rq_connect_cookie); 2410 break; 2411 default: 2412 /* 2413 * We were unable to reply and will have to drop the 2414 * request. The server should reconnect and retransmit. 2415 */ 2416 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2417 "error: %d\n", task->tk_status); 2418 break; 2419 } 2420 task->tk_action = rpc_exit_task; 2421 } 2422 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2423 2424 /* 2425 * 6. Sort out the RPC call status 2426 */ 2427 static void 2428 call_status(struct rpc_task *task) 2429 { 2430 struct rpc_clnt *clnt = task->tk_client; 2431 int status; 2432 2433 if (!task->tk_msg.rpc_proc->p_proc) 2434 trace_xprt_ping(task->tk_xprt, task->tk_status); 2435 2436 status = task->tk_status; 2437 if (status >= 0) { 2438 task->tk_action = call_decode; 2439 return; 2440 } 2441 2442 trace_rpc_call_status(task); 2443 task->tk_status = 0; 2444 switch(status) { 2445 case -EHOSTDOWN: 2446 case -ENETDOWN: 2447 case -EHOSTUNREACH: 2448 case -ENETUNREACH: 2449 case -EPERM: 2450 if (RPC_IS_SOFTCONN(task)) 2451 goto out_exit; 2452 /* 2453 * Delay any retries for 3 seconds, then handle as if it 2454 * were a timeout. 2455 */ 2456 rpc_delay(task, 3*HZ); 2457 fallthrough; 2458 case -ETIMEDOUT: 2459 break; 2460 case -ECONNREFUSED: 2461 case -ECONNRESET: 2462 case -ECONNABORTED: 2463 case -ENOTCONN: 2464 rpc_force_rebind(clnt); 2465 break; 2466 case -EADDRINUSE: 2467 rpc_delay(task, 3*HZ); 2468 fallthrough; 2469 case -EPIPE: 2470 case -EAGAIN: 2471 break; 2472 case -ENFILE: 2473 case -ENOBUFS: 2474 case -ENOMEM: 2475 rpc_delay(task, HZ>>2); 2476 break; 2477 case -EIO: 2478 /* shutdown or soft timeout */ 2479 goto out_exit; 2480 default: 2481 if (clnt->cl_chatty) 2482 printk("%s: RPC call returned error %d\n", 2483 clnt->cl_program->name, -status); 2484 goto out_exit; 2485 } 2486 task->tk_action = call_encode; 2487 rpc_check_timeout(task); 2488 return; 2489 out_exit: 2490 rpc_call_rpcerror(task, status); 2491 } 2492 2493 static bool 2494 rpc_check_connected(const struct rpc_rqst *req) 2495 { 2496 /* No allocated request or transport? return true */ 2497 if (!req || !req->rq_xprt) 2498 return true; 2499 return xprt_connected(req->rq_xprt); 2500 } 2501 2502 static void 2503 rpc_check_timeout(struct rpc_task *task) 2504 { 2505 struct rpc_clnt *clnt = task->tk_client; 2506 2507 if (RPC_SIGNALLED(task)) 2508 return; 2509 2510 if (xprt_adjust_timeout(task->tk_rqstp) == 0) 2511 return; 2512 2513 trace_rpc_timeout_status(task); 2514 task->tk_timeouts++; 2515 2516 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) { 2517 rpc_call_rpcerror(task, -ETIMEDOUT); 2518 return; 2519 } 2520 2521 if (RPC_IS_SOFT(task)) { 2522 /* 2523 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has 2524 * been sent, it should time out only if the transport 2525 * connection gets terminally broken. 2526 */ 2527 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) && 2528 rpc_check_connected(task->tk_rqstp)) 2529 return; 2530 2531 if (clnt->cl_chatty) { 2532 pr_notice_ratelimited( 2533 "%s: server %s not responding, timed out\n", 2534 clnt->cl_program->name, 2535 task->tk_xprt->servername); 2536 } 2537 if (task->tk_flags & RPC_TASK_TIMEOUT) 2538 rpc_call_rpcerror(task, -ETIMEDOUT); 2539 else 2540 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT); 2541 return; 2542 } 2543 2544 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2545 task->tk_flags |= RPC_CALL_MAJORSEEN; 2546 if (clnt->cl_chatty) { 2547 pr_notice_ratelimited( 2548 "%s: server %s not responding, still trying\n", 2549 clnt->cl_program->name, 2550 task->tk_xprt->servername); 2551 } 2552 } 2553 rpc_force_rebind(clnt); 2554 /* 2555 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2556 * event? RFC2203 requires the server to drop all such requests. 2557 */ 2558 rpcauth_invalcred(task); 2559 } 2560 2561 /* 2562 * 7. Decode the RPC reply 2563 */ 2564 static void 2565 call_decode(struct rpc_task *task) 2566 { 2567 struct rpc_clnt *clnt = task->tk_client; 2568 struct rpc_rqst *req = task->tk_rqstp; 2569 struct xdr_stream xdr; 2570 int err; 2571 2572 if (!task->tk_msg.rpc_proc->p_decode) { 2573 task->tk_action = rpc_exit_task; 2574 return; 2575 } 2576 2577 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2578 if (clnt->cl_chatty) { 2579 pr_notice_ratelimited("%s: server %s OK\n", 2580 clnt->cl_program->name, 2581 task->tk_xprt->servername); 2582 } 2583 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2584 } 2585 2586 /* 2587 * Did we ever call xprt_complete_rqst()? If not, we should assume 2588 * the message is incomplete. 2589 */ 2590 err = -EAGAIN; 2591 if (!req->rq_reply_bytes_recvd) 2592 goto out; 2593 2594 /* Ensure that we see all writes made by xprt_complete_rqst() 2595 * before it changed req->rq_reply_bytes_recvd. 2596 */ 2597 smp_rmb(); 2598 2599 req->rq_rcv_buf.len = req->rq_private_buf.len; 2600 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf); 2601 2602 /* Check that the softirq receive buffer is valid */ 2603 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2604 sizeof(req->rq_rcv_buf)) != 0); 2605 2606 xdr_init_decode(&xdr, &req->rq_rcv_buf, 2607 req->rq_rcv_buf.head[0].iov_base, req); 2608 err = rpc_decode_header(task, &xdr); 2609 out: 2610 switch (err) { 2611 case 0: 2612 task->tk_action = rpc_exit_task; 2613 task->tk_status = rpcauth_unwrap_resp(task, &xdr); 2614 xdr_finish_decode(&xdr); 2615 return; 2616 case -EAGAIN: 2617 task->tk_status = 0; 2618 if (task->tk_client->cl_discrtry) 2619 xprt_conditional_disconnect(req->rq_xprt, 2620 req->rq_connect_cookie); 2621 task->tk_action = call_encode; 2622 rpc_check_timeout(task); 2623 break; 2624 case -EKEYREJECTED: 2625 task->tk_action = call_reserve; 2626 rpc_check_timeout(task); 2627 rpcauth_invalcred(task); 2628 /* Ensure we obtain a new XID if we retry! */ 2629 xprt_release(task); 2630 } 2631 } 2632 2633 static int 2634 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr) 2635 { 2636 struct rpc_clnt *clnt = task->tk_client; 2637 struct rpc_rqst *req = task->tk_rqstp; 2638 __be32 *p; 2639 int error; 2640 2641 error = -EMSGSIZE; 2642 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2); 2643 if (!p) 2644 goto out_fail; 2645 *p++ = req->rq_xid; 2646 *p++ = rpc_call; 2647 *p++ = cpu_to_be32(RPC_VERSION); 2648 *p++ = cpu_to_be32(clnt->cl_prog); 2649 *p++ = cpu_to_be32(clnt->cl_vers); 2650 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc); 2651 2652 error = rpcauth_marshcred(task, xdr); 2653 if (error < 0) 2654 goto out_fail; 2655 return 0; 2656 out_fail: 2657 trace_rpc_bad_callhdr(task); 2658 rpc_call_rpcerror(task, error); 2659 return error; 2660 } 2661 2662 static noinline int 2663 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr) 2664 { 2665 struct rpc_clnt *clnt = task->tk_client; 2666 int error; 2667 __be32 *p; 2668 2669 /* RFC-1014 says that the representation of XDR data must be a 2670 * multiple of four bytes 2671 * - if it isn't pointer subtraction in the NFS client may give 2672 * undefined results 2673 */ 2674 if (task->tk_rqstp->rq_rcv_buf.len & 3) 2675 goto out_unparsable; 2676 2677 p = xdr_inline_decode(xdr, 3 * sizeof(*p)); 2678 if (!p) 2679 goto out_unparsable; 2680 p++; /* skip XID */ 2681 if (*p++ != rpc_reply) 2682 goto out_unparsable; 2683 if (*p++ != rpc_msg_accepted) 2684 goto out_msg_denied; 2685 2686 error = rpcauth_checkverf(task, xdr); 2687 if (error) 2688 goto out_verifier; 2689 2690 p = xdr_inline_decode(xdr, sizeof(*p)); 2691 if (!p) 2692 goto out_unparsable; 2693 switch (*p) { 2694 case rpc_success: 2695 return 0; 2696 case rpc_prog_unavail: 2697 trace_rpc__prog_unavail(task); 2698 error = -EPFNOSUPPORT; 2699 goto out_err; 2700 case rpc_prog_mismatch: 2701 trace_rpc__prog_mismatch(task); 2702 error = -EPROTONOSUPPORT; 2703 goto out_err; 2704 case rpc_proc_unavail: 2705 trace_rpc__proc_unavail(task); 2706 error = -EOPNOTSUPP; 2707 goto out_err; 2708 case rpc_garbage_args: 2709 case rpc_system_err: 2710 trace_rpc__garbage_args(task); 2711 error = -EIO; 2712 break; 2713 default: 2714 goto out_unparsable; 2715 } 2716 2717 out_garbage: 2718 clnt->cl_stats->rpcgarbage++; 2719 if (task->tk_garb_retry) { 2720 task->tk_garb_retry--; 2721 task->tk_action = call_encode; 2722 return -EAGAIN; 2723 } 2724 out_err: 2725 rpc_call_rpcerror(task, error); 2726 return error; 2727 2728 out_unparsable: 2729 trace_rpc__unparsable(task); 2730 error = -EIO; 2731 goto out_garbage; 2732 2733 out_verifier: 2734 trace_rpc_bad_verifier(task); 2735 switch (error) { 2736 case -EPROTONOSUPPORT: 2737 goto out_err; 2738 case -EACCES: 2739 /* Re-encode with a fresh cred */ 2740 fallthrough; 2741 default: 2742 goto out_garbage; 2743 } 2744 2745 out_msg_denied: 2746 error = -EACCES; 2747 p = xdr_inline_decode(xdr, sizeof(*p)); 2748 if (!p) 2749 goto out_unparsable; 2750 switch (*p++) { 2751 case rpc_auth_error: 2752 break; 2753 case rpc_mismatch: 2754 trace_rpc__mismatch(task); 2755 error = -EPROTONOSUPPORT; 2756 goto out_err; 2757 default: 2758 goto out_unparsable; 2759 } 2760 2761 p = xdr_inline_decode(xdr, sizeof(*p)); 2762 if (!p) 2763 goto out_unparsable; 2764 switch (*p++) { 2765 case rpc_autherr_rejectedcred: 2766 case rpc_autherr_rejectedverf: 2767 case rpcsec_gsserr_credproblem: 2768 case rpcsec_gsserr_ctxproblem: 2769 rpcauth_invalcred(task); 2770 if (!task->tk_cred_retry) 2771 break; 2772 task->tk_cred_retry--; 2773 trace_rpc__stale_creds(task); 2774 return -EKEYREJECTED; 2775 case rpc_autherr_badcred: 2776 case rpc_autherr_badverf: 2777 /* possibly garbled cred/verf? */ 2778 if (!task->tk_garb_retry) 2779 break; 2780 task->tk_garb_retry--; 2781 trace_rpc__bad_creds(task); 2782 task->tk_action = call_encode; 2783 return -EAGAIN; 2784 case rpc_autherr_tooweak: 2785 trace_rpc__auth_tooweak(task); 2786 pr_warn("RPC: server %s requires stronger authentication.\n", 2787 task->tk_xprt->servername); 2788 break; 2789 default: 2790 goto out_unparsable; 2791 } 2792 goto out_err; 2793 } 2794 2795 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2796 const void *obj) 2797 { 2798 } 2799 2800 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 2801 void *obj) 2802 { 2803 return 0; 2804 } 2805 2806 static const struct rpc_procinfo rpcproc_null = { 2807 .p_encode = rpcproc_encode_null, 2808 .p_decode = rpcproc_decode_null, 2809 }; 2810 2811 static const struct rpc_procinfo rpcproc_null_noreply = { 2812 .p_encode = rpcproc_encode_null, 2813 }; 2814 2815 static void 2816 rpc_null_call_prepare(struct rpc_task *task, void *data) 2817 { 2818 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT; 2819 rpc_call_start(task); 2820 } 2821 2822 static const struct rpc_call_ops rpc_null_ops = { 2823 .rpc_call_prepare = rpc_null_call_prepare, 2824 .rpc_call_done = rpc_default_callback, 2825 }; 2826 2827 static 2828 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2829 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2830 const struct rpc_call_ops *ops, void *data) 2831 { 2832 struct rpc_message msg = { 2833 .rpc_proc = &rpcproc_null, 2834 }; 2835 struct rpc_task_setup task_setup_data = { 2836 .rpc_client = clnt, 2837 .rpc_xprt = xprt, 2838 .rpc_message = &msg, 2839 .rpc_op_cred = cred, 2840 .callback_ops = ops ?: &rpc_null_ops, 2841 .callback_data = data, 2842 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN | 2843 RPC_TASK_NULLCREDS, 2844 }; 2845 2846 return rpc_run_task(&task_setup_data); 2847 } 2848 2849 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2850 { 2851 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2852 } 2853 EXPORT_SYMBOL_GPL(rpc_call_null); 2854 2855 static int rpc_ping(struct rpc_clnt *clnt) 2856 { 2857 struct rpc_task *task; 2858 int status; 2859 2860 if (clnt->cl_auth->au_ops->ping) 2861 return clnt->cl_auth->au_ops->ping(clnt); 2862 2863 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL); 2864 if (IS_ERR(task)) 2865 return PTR_ERR(task); 2866 status = task->tk_status; 2867 rpc_put_task(task); 2868 return status; 2869 } 2870 2871 static int rpc_ping_noreply(struct rpc_clnt *clnt) 2872 { 2873 struct rpc_message msg = { 2874 .rpc_proc = &rpcproc_null_noreply, 2875 }; 2876 struct rpc_task_setup task_setup_data = { 2877 .rpc_client = clnt, 2878 .rpc_message = &msg, 2879 .callback_ops = &rpc_null_ops, 2880 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS, 2881 }; 2882 struct rpc_task *task; 2883 int status; 2884 2885 task = rpc_run_task(&task_setup_data); 2886 if (IS_ERR(task)) 2887 return PTR_ERR(task); 2888 status = task->tk_status; 2889 rpc_put_task(task); 2890 return status; 2891 } 2892 2893 struct rpc_cb_add_xprt_calldata { 2894 struct rpc_xprt_switch *xps; 2895 struct rpc_xprt *xprt; 2896 }; 2897 2898 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2899 { 2900 struct rpc_cb_add_xprt_calldata *data = calldata; 2901 2902 if (task->tk_status == 0) 2903 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2904 } 2905 2906 static void rpc_cb_add_xprt_release(void *calldata) 2907 { 2908 struct rpc_cb_add_xprt_calldata *data = calldata; 2909 2910 xprt_put(data->xprt); 2911 xprt_switch_put(data->xps); 2912 kfree(data); 2913 } 2914 2915 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2916 .rpc_call_prepare = rpc_null_call_prepare, 2917 .rpc_call_done = rpc_cb_add_xprt_done, 2918 .rpc_release = rpc_cb_add_xprt_release, 2919 }; 2920 2921 /** 2922 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2923 * @clnt: pointer to struct rpc_clnt 2924 * @xps: pointer to struct rpc_xprt_switch, 2925 * @xprt: pointer struct rpc_xprt 2926 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport 2927 */ 2928 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2929 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2930 void *in_max_connect) 2931 { 2932 struct rpc_cb_add_xprt_calldata *data; 2933 struct rpc_task *task; 2934 int max_connect = clnt->cl_max_connect; 2935 2936 if (in_max_connect) 2937 max_connect = *(int *)in_max_connect; 2938 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) { 2939 rcu_read_lock(); 2940 pr_warn("SUNRPC: reached max allowed number (%d) did not add " 2941 "transport to server: %s\n", max_connect, 2942 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 2943 rcu_read_unlock(); 2944 return -EINVAL; 2945 } 2946 2947 data = kmalloc(sizeof(*data), GFP_KERNEL); 2948 if (!data) 2949 return -ENOMEM; 2950 data->xps = xprt_switch_get(xps); 2951 data->xprt = xprt_get(xprt); 2952 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) { 2953 rpc_cb_add_xprt_release(data); 2954 goto success; 2955 } 2956 2957 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC, 2958 &rpc_cb_add_xprt_call_ops, data); 2959 if (IS_ERR(task)) 2960 return PTR_ERR(task); 2961 2962 data->xps->xps_nunique_destaddr_xprts++; 2963 rpc_put_task(task); 2964 success: 2965 return 1; 2966 } 2967 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2968 2969 static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt, 2970 struct rpc_xprt *xprt, 2971 struct rpc_add_xprt_test *data) 2972 { 2973 struct rpc_task *task; 2974 int status = -EADDRINUSE; 2975 2976 /* Test the connection */ 2977 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL); 2978 if (IS_ERR(task)) 2979 return PTR_ERR(task); 2980 2981 status = task->tk_status; 2982 rpc_put_task(task); 2983 2984 if (status < 0) 2985 return status; 2986 2987 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */ 2988 data->add_xprt_test(clnt, xprt, data->data); 2989 2990 return 0; 2991 } 2992 2993 /** 2994 * rpc_clnt_setup_test_and_add_xprt() 2995 * 2996 * This is an rpc_clnt_add_xprt setup() function which returns 1 so: 2997 * 1) caller of the test function must dereference the rpc_xprt_switch 2998 * and the rpc_xprt. 2999 * 2) test function must call rpc_xprt_switch_add_xprt, usually in 3000 * the rpc_call_done routine. 3001 * 3002 * Upon success (return of 1), the test function adds the new 3003 * transport to the rpc_clnt xprt switch 3004 * 3005 * @clnt: struct rpc_clnt to get the new transport 3006 * @xps: the rpc_xprt_switch to hold the new transport 3007 * @xprt: the rpc_xprt to test 3008 * @data: a struct rpc_add_xprt_test pointer that holds the test function 3009 * and test function call data 3010 */ 3011 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt, 3012 struct rpc_xprt_switch *xps, 3013 struct rpc_xprt *xprt, 3014 void *data) 3015 { 3016 int status = -EADDRINUSE; 3017 3018 xprt = xprt_get(xprt); 3019 xprt_switch_get(xps); 3020 3021 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr)) 3022 goto out_err; 3023 3024 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3025 if (status < 0) 3026 goto out_err; 3027 3028 status = 1; 3029 out_err: 3030 xprt_put(xprt); 3031 xprt_switch_put(xps); 3032 if (status < 0) 3033 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not " 3034 "added\n", status, 3035 xprt->address_strings[RPC_DISPLAY_ADDR]); 3036 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */ 3037 return status; 3038 } 3039 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt); 3040 3041 /** 3042 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 3043 * @clnt: pointer to struct rpc_clnt 3044 * @xprtargs: pointer to struct xprt_create 3045 * @setup: callback to test and/or set up the connection 3046 * @data: pointer to setup function data 3047 * 3048 * Creates a new transport using the parameters set in args and 3049 * adds it to clnt. 3050 * If ping is set, then test that connectivity succeeds before 3051 * adding the new transport. 3052 * 3053 */ 3054 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 3055 struct xprt_create *xprtargs, 3056 int (*setup)(struct rpc_clnt *, 3057 struct rpc_xprt_switch *, 3058 struct rpc_xprt *, 3059 void *), 3060 void *data) 3061 { 3062 struct rpc_xprt_switch *xps; 3063 struct rpc_xprt *xprt; 3064 unsigned long connect_timeout; 3065 unsigned long reconnect_timeout; 3066 unsigned char resvport, reuseport; 3067 int ret = 0, ident; 3068 3069 rcu_read_lock(); 3070 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3071 xprt = xprt_iter_xprt(&clnt->cl_xpi); 3072 if (xps == NULL || xprt == NULL) { 3073 rcu_read_unlock(); 3074 xprt_switch_put(xps); 3075 return -EAGAIN; 3076 } 3077 resvport = xprt->resvport; 3078 reuseport = xprt->reuseport; 3079 connect_timeout = xprt->connect_timeout; 3080 reconnect_timeout = xprt->max_reconnect_timeout; 3081 ident = xprt->xprt_class->ident; 3082 rcu_read_unlock(); 3083 3084 if (!xprtargs->ident) 3085 xprtargs->ident = ident; 3086 xprtargs->xprtsec = clnt->cl_xprtsec; 3087 xprt = xprt_create_transport(xprtargs); 3088 if (IS_ERR(xprt)) { 3089 ret = PTR_ERR(xprt); 3090 goto out_put_switch; 3091 } 3092 xprt->resvport = resvport; 3093 xprt->reuseport = reuseport; 3094 3095 if (xprtargs->connect_timeout) 3096 connect_timeout = xprtargs->connect_timeout; 3097 if (xprtargs->reconnect_timeout) 3098 reconnect_timeout = xprtargs->reconnect_timeout; 3099 if (xprt->ops->set_connect_timeout != NULL) 3100 xprt->ops->set_connect_timeout(xprt, 3101 connect_timeout, 3102 reconnect_timeout); 3103 3104 rpc_xprt_switch_set_roundrobin(xps); 3105 if (setup) { 3106 ret = setup(clnt, xps, xprt, data); 3107 if (ret != 0) 3108 goto out_put_xprt; 3109 } 3110 rpc_xprt_switch_add_xprt(xps, xprt); 3111 out_put_xprt: 3112 xprt_put(xprt); 3113 out_put_switch: 3114 xprt_switch_put(xps); 3115 return ret; 3116 } 3117 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 3118 3119 static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt, 3120 struct rpc_xprt *xprt, 3121 struct rpc_add_xprt_test *data) 3122 { 3123 struct rpc_xprt_switch *xps; 3124 struct rpc_xprt *main_xprt; 3125 int status = 0; 3126 3127 xprt_get(xprt); 3128 3129 rcu_read_lock(); 3130 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3131 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3132 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3133 (struct sockaddr *)&main_xprt->addr); 3134 rcu_read_unlock(); 3135 xprt_put(main_xprt); 3136 if (status || !test_bit(XPRT_OFFLINE, &xprt->state)) 3137 goto out; 3138 3139 status = rpc_clnt_add_xprt_helper(clnt, xprt, data); 3140 out: 3141 xprt_put(xprt); 3142 xprt_switch_put(xps); 3143 return status; 3144 } 3145 3146 /* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking 3147 * @clnt rpc_clnt structure 3148 * 3149 * For each offlined transport found in the rpc_clnt structure call 3150 * the function rpc_xprt_probe_trunked() which will determine if this 3151 * transport still belongs to the trunking group. 3152 */ 3153 void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt, 3154 struct rpc_add_xprt_test *data) 3155 { 3156 struct rpc_xprt_iter xpi; 3157 int ret; 3158 3159 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi); 3160 if (ret) 3161 return; 3162 for (;;) { 3163 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 3164 3165 if (!xprt) 3166 break; 3167 ret = rpc_xprt_probe_trunked(clnt, xprt, data); 3168 xprt_put(xprt); 3169 if (ret < 0) 3170 break; 3171 xprt_iter_rewind(&xpi); 3172 } 3173 xprt_iter_destroy(&xpi); 3174 } 3175 EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts); 3176 3177 static int rpc_xprt_offline(struct rpc_clnt *clnt, 3178 struct rpc_xprt *xprt, 3179 void *data) 3180 { 3181 struct rpc_xprt *main_xprt; 3182 struct rpc_xprt_switch *xps; 3183 int err = 0; 3184 3185 xprt_get(xprt); 3186 3187 rcu_read_lock(); 3188 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 3189 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3190 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr, 3191 (struct sockaddr *)&main_xprt->addr); 3192 rcu_read_unlock(); 3193 xprt_put(main_xprt); 3194 if (err) 3195 goto out; 3196 3197 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) { 3198 err = -EINTR; 3199 goto out; 3200 } 3201 xprt_set_offline_locked(xprt, xps); 3202 3203 xprt_release_write(xprt, NULL); 3204 out: 3205 xprt_put(xprt); 3206 xprt_switch_put(xps); 3207 return err; 3208 } 3209 3210 /* rpc_clnt_manage_trunked_xprts -- offline trunked transports 3211 * @clnt rpc_clnt structure 3212 * 3213 * For each active transport found in the rpc_clnt structure call 3214 * the function rpc_xprt_offline() which will identify trunked transports 3215 * and will mark them offline. 3216 */ 3217 void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt) 3218 { 3219 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL); 3220 } 3221 EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts); 3222 3223 struct connect_timeout_data { 3224 unsigned long connect_timeout; 3225 unsigned long reconnect_timeout; 3226 }; 3227 3228 static int 3229 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt, 3230 struct rpc_xprt *xprt, 3231 void *data) 3232 { 3233 struct connect_timeout_data *timeo = data; 3234 3235 if (xprt->ops->set_connect_timeout) 3236 xprt->ops->set_connect_timeout(xprt, 3237 timeo->connect_timeout, 3238 timeo->reconnect_timeout); 3239 return 0; 3240 } 3241 3242 void 3243 rpc_set_connect_timeout(struct rpc_clnt *clnt, 3244 unsigned long connect_timeout, 3245 unsigned long reconnect_timeout) 3246 { 3247 struct connect_timeout_data timeout = { 3248 .connect_timeout = connect_timeout, 3249 .reconnect_timeout = reconnect_timeout, 3250 }; 3251 rpc_clnt_iterate_for_each_xprt(clnt, 3252 rpc_xprt_set_connect_timeout, 3253 &timeout); 3254 } 3255 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout); 3256 3257 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt) 3258 { 3259 rcu_read_lock(); 3260 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 3261 rcu_read_unlock(); 3262 } 3263 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put); 3264 3265 void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3266 { 3267 struct rpc_xprt_switch *xps; 3268 3269 rcu_read_lock(); 3270 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3271 rcu_read_unlock(); 3272 xprt_set_online_locked(xprt, xps); 3273 } 3274 3275 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3276 { 3277 if (rpc_clnt_xprt_switch_has_addr(clnt, 3278 (const struct sockaddr *)&xprt->addr)) { 3279 return rpc_clnt_xprt_set_online(clnt, xprt); 3280 } 3281 rcu_read_lock(); 3282 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3283 xprt); 3284 rcu_read_unlock(); 3285 } 3286 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt); 3287 3288 void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt) 3289 { 3290 struct rpc_xprt_switch *xps; 3291 3292 rcu_read_lock(); 3293 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3294 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch), 3295 xprt, 0); 3296 xps->xps_nunique_destaddr_xprts--; 3297 rcu_read_unlock(); 3298 } 3299 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt); 3300 3301 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt, 3302 const struct sockaddr *sap) 3303 { 3304 struct rpc_xprt_switch *xps; 3305 bool ret; 3306 3307 rcu_read_lock(); 3308 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch); 3309 ret = rpc_xprt_switch_has_addr(xps, sap); 3310 rcu_read_unlock(); 3311 return ret; 3312 } 3313 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr); 3314 3315 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 3316 static void rpc_show_header(void) 3317 { 3318 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 3319 "-timeout ---ops--\n"); 3320 } 3321 3322 static void rpc_show_task(const struct rpc_clnt *clnt, 3323 const struct rpc_task *task) 3324 { 3325 const char *rpc_waitq = "none"; 3326 3327 if (RPC_IS_QUEUED(task)) 3328 rpc_waitq = rpc_qname(task->tk_waitqueue); 3329 3330 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 3331 task->tk_pid, task->tk_flags, task->tk_status, 3332 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops, 3333 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 3334 task->tk_action, rpc_waitq); 3335 } 3336 3337 void rpc_show_tasks(struct net *net) 3338 { 3339 struct rpc_clnt *clnt; 3340 struct rpc_task *task; 3341 int header = 0; 3342 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 3343 3344 spin_lock(&sn->rpc_client_lock); 3345 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 3346 spin_lock(&clnt->cl_lock); 3347 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 3348 if (!header) { 3349 rpc_show_header(); 3350 header++; 3351 } 3352 rpc_show_task(clnt, task); 3353 } 3354 spin_unlock(&clnt->cl_lock); 3355 } 3356 spin_unlock(&sn->rpc_client_lock); 3357 } 3358 #endif 3359 3360 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 3361 static int 3362 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 3363 struct rpc_xprt *xprt, 3364 void *dummy) 3365 { 3366 return xprt_enable_swap(xprt); 3367 } 3368 3369 int 3370 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 3371 { 3372 while (clnt != clnt->cl_parent) 3373 clnt = clnt->cl_parent; 3374 if (atomic_inc_return(&clnt->cl_swapper) == 1) 3375 return rpc_clnt_iterate_for_each_xprt(clnt, 3376 rpc_clnt_swap_activate_callback, NULL); 3377 return 0; 3378 } 3379 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 3380 3381 static int 3382 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 3383 struct rpc_xprt *xprt, 3384 void *dummy) 3385 { 3386 xprt_disable_swap(xprt); 3387 return 0; 3388 } 3389 3390 void 3391 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 3392 { 3393 while (clnt != clnt->cl_parent) 3394 clnt = clnt->cl_parent; 3395 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 3396 rpc_clnt_iterate_for_each_xprt(clnt, 3397 rpc_clnt_swap_deactivate_callback, NULL); 3398 } 3399 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 3400 #endif /* CONFIG_SUNRPC_SWAP */ 3401