1 /* 2 * linux/net/sunrpc/clnt.c 3 * 4 * This file contains the high-level RPC interface. 5 * It is modeled as a finite state machine to support both synchronous 6 * and asynchronous requests. 7 * 8 * - RPC header generation and argument serialization. 9 * - Credential refresh. 10 * - TCP connect handling. 11 * - Retry of operation when it is suspected the operation failed because 12 * of uid squashing on the server, or when the credentials were stale 13 * and need to be refreshed, or when a packet was damaged in transit. 14 * This may be have to be moved to the VFS layer. 15 * 16 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 18 */ 19 20 21 #include <linux/module.h> 22 #include <linux/types.h> 23 #include <linux/kallsyms.h> 24 #include <linux/mm.h> 25 #include <linux/namei.h> 26 #include <linux/mount.h> 27 #include <linux/slab.h> 28 #include <linux/rcupdate.h> 29 #include <linux/utsname.h> 30 #include <linux/workqueue.h> 31 #include <linux/in.h> 32 #include <linux/in6.h> 33 #include <linux/un.h> 34 35 #include <linux/sunrpc/clnt.h> 36 #include <linux/sunrpc/addr.h> 37 #include <linux/sunrpc/rpc_pipe_fs.h> 38 #include <linux/sunrpc/metrics.h> 39 #include <linux/sunrpc/bc_xprt.h> 40 #include <trace/events/sunrpc.h> 41 42 #include "sunrpc.h" 43 #include "netns.h" 44 45 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 46 # define RPCDBG_FACILITY RPCDBG_CALL 47 #endif 48 49 #define dprint_status(t) \ 50 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \ 51 __func__, t->tk_status) 52 53 /* 54 * All RPC clients are linked into this list 55 */ 56 57 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 58 59 60 static void call_start(struct rpc_task *task); 61 static void call_reserve(struct rpc_task *task); 62 static void call_reserveresult(struct rpc_task *task); 63 static void call_allocate(struct rpc_task *task); 64 static void call_decode(struct rpc_task *task); 65 static void call_bind(struct rpc_task *task); 66 static void call_bind_status(struct rpc_task *task); 67 static void call_transmit(struct rpc_task *task); 68 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 69 static void call_bc_transmit(struct rpc_task *task); 70 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 71 static void call_status(struct rpc_task *task); 72 static void call_transmit_status(struct rpc_task *task); 73 static void call_refresh(struct rpc_task *task); 74 static void call_refreshresult(struct rpc_task *task); 75 static void call_timeout(struct rpc_task *task); 76 static void call_connect(struct rpc_task *task); 77 static void call_connect_status(struct rpc_task *task); 78 79 static __be32 *rpc_encode_header(struct rpc_task *task); 80 static __be32 *rpc_verify_header(struct rpc_task *task); 81 static int rpc_ping(struct rpc_clnt *clnt); 82 83 static void rpc_register_client(struct rpc_clnt *clnt) 84 { 85 struct net *net = rpc_net_ns(clnt); 86 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 87 88 spin_lock(&sn->rpc_client_lock); 89 list_add(&clnt->cl_clients, &sn->all_clients); 90 spin_unlock(&sn->rpc_client_lock); 91 } 92 93 static void rpc_unregister_client(struct rpc_clnt *clnt) 94 { 95 struct net *net = rpc_net_ns(clnt); 96 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 97 98 spin_lock(&sn->rpc_client_lock); 99 list_del(&clnt->cl_clients); 100 spin_unlock(&sn->rpc_client_lock); 101 } 102 103 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 104 { 105 rpc_remove_client_dir(clnt); 106 } 107 108 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt) 109 { 110 struct net *net = rpc_net_ns(clnt); 111 struct super_block *pipefs_sb; 112 113 pipefs_sb = rpc_get_sb_net(net); 114 if (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 if (clnt->cl_program->pipe_dir_name != NULL) { 156 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt); 157 if (IS_ERR(dentry)) 158 return PTR_ERR(dentry); 159 } 160 return 0; 161 } 162 163 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event) 164 { 165 if (clnt->cl_program->pipe_dir_name == NULL) 166 return 1; 167 168 switch (event) { 169 case RPC_PIPEFS_MOUNT: 170 if (clnt->cl_pipedir_objects.pdh_dentry != NULL) 171 return 1; 172 if (atomic_read(&clnt->cl_count) == 0) 173 return 1; 174 break; 175 case RPC_PIPEFS_UMOUNT: 176 if (clnt->cl_pipedir_objects.pdh_dentry == NULL) 177 return 1; 178 break; 179 } 180 return 0; 181 } 182 183 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event, 184 struct super_block *sb) 185 { 186 struct dentry *dentry; 187 int err = 0; 188 189 switch (event) { 190 case RPC_PIPEFS_MOUNT: 191 dentry = rpc_setup_pipedir_sb(sb, clnt); 192 if (!dentry) 193 return -ENOENT; 194 if (IS_ERR(dentry)) 195 return PTR_ERR(dentry); 196 break; 197 case RPC_PIPEFS_UMOUNT: 198 __rpc_clnt_remove_pipedir(clnt); 199 break; 200 default: 201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event); 202 return -ENOTSUPP; 203 } 204 return err; 205 } 206 207 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event, 208 struct super_block *sb) 209 { 210 int error = 0; 211 212 for (;; clnt = clnt->cl_parent) { 213 if (!rpc_clnt_skip_event(clnt, event)) 214 error = __rpc_clnt_handle_event(clnt, event, sb); 215 if (error || clnt == clnt->cl_parent) 216 break; 217 } 218 return error; 219 } 220 221 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event) 222 { 223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 224 struct rpc_clnt *clnt; 225 226 spin_lock(&sn->rpc_client_lock); 227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 228 if (rpc_clnt_skip_event(clnt, event)) 229 continue; 230 spin_unlock(&sn->rpc_client_lock); 231 return clnt; 232 } 233 spin_unlock(&sn->rpc_client_lock); 234 return NULL; 235 } 236 237 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, 238 void *ptr) 239 { 240 struct super_block *sb = ptr; 241 struct rpc_clnt *clnt; 242 int error = 0; 243 244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) { 245 error = __rpc_pipefs_event(clnt, event, sb); 246 if (error) 247 break; 248 } 249 return error; 250 } 251 252 static struct notifier_block rpc_clients_block = { 253 .notifier_call = rpc_pipefs_event, 254 .priority = SUNRPC_PIPEFS_RPC_PRIO, 255 }; 256 257 int rpc_clients_notifier_register(void) 258 { 259 return rpc_pipefs_notifier_register(&rpc_clients_block); 260 } 261 262 void rpc_clients_notifier_unregister(void) 263 { 264 return rpc_pipefs_notifier_unregister(&rpc_clients_block); 265 } 266 267 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt, 268 struct rpc_xprt *xprt, 269 const struct rpc_timeout *timeout) 270 { 271 struct rpc_xprt *old; 272 273 spin_lock(&clnt->cl_lock); 274 old = rcu_dereference_protected(clnt->cl_xprt, 275 lockdep_is_held(&clnt->cl_lock)); 276 277 if (!xprt_bound(xprt)) 278 clnt->cl_autobind = 1; 279 280 clnt->cl_timeout = timeout; 281 rcu_assign_pointer(clnt->cl_xprt, xprt); 282 spin_unlock(&clnt->cl_lock); 283 284 return old; 285 } 286 287 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename) 288 { 289 clnt->cl_nodelen = strlcpy(clnt->cl_nodename, 290 nodename, sizeof(clnt->cl_nodename)); 291 } 292 293 static int rpc_client_register(struct rpc_clnt *clnt, 294 rpc_authflavor_t pseudoflavor, 295 const char *client_name) 296 { 297 struct rpc_auth_create_args auth_args = { 298 .pseudoflavor = pseudoflavor, 299 .target_name = client_name, 300 }; 301 struct rpc_auth *auth; 302 struct net *net = rpc_net_ns(clnt); 303 struct super_block *pipefs_sb; 304 int err; 305 306 rpc_clnt_debugfs_register(clnt); 307 308 pipefs_sb = rpc_get_sb_net(net); 309 if (pipefs_sb) { 310 err = rpc_setup_pipedir(pipefs_sb, clnt); 311 if (err) 312 goto out; 313 } 314 315 rpc_register_client(clnt); 316 if (pipefs_sb) 317 rpc_put_sb_net(net); 318 319 auth = rpcauth_create(&auth_args, clnt); 320 if (IS_ERR(auth)) { 321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n", 322 pseudoflavor); 323 err = PTR_ERR(auth); 324 goto err_auth; 325 } 326 return 0; 327 err_auth: 328 pipefs_sb = rpc_get_sb_net(net); 329 rpc_unregister_client(clnt); 330 __rpc_clnt_remove_pipedir(clnt); 331 out: 332 if (pipefs_sb) 333 rpc_put_sb_net(net); 334 rpc_clnt_debugfs_unregister(clnt); 335 return err; 336 } 337 338 static DEFINE_IDA(rpc_clids); 339 340 static int rpc_alloc_clid(struct rpc_clnt *clnt) 341 { 342 int clid; 343 344 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL); 345 if (clid < 0) 346 return clid; 347 clnt->cl_clid = clid; 348 return 0; 349 } 350 351 static void rpc_free_clid(struct rpc_clnt *clnt) 352 { 353 ida_simple_remove(&rpc_clids, clnt->cl_clid); 354 } 355 356 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, 357 struct rpc_xprt_switch *xps, 358 struct rpc_xprt *xprt, 359 struct rpc_clnt *parent) 360 { 361 const struct rpc_program *program = args->program; 362 const struct rpc_version *version; 363 struct rpc_clnt *clnt = NULL; 364 const struct rpc_timeout *timeout; 365 const char *nodename = args->nodename; 366 int err; 367 368 /* sanity check the name before trying to print it */ 369 dprintk("RPC: creating %s client for %s (xprt %p)\n", 370 program->name, args->servername, xprt); 371 372 err = rpciod_up(); 373 if (err) 374 goto out_no_rpciod; 375 376 err = -EINVAL; 377 if (args->version >= program->nrvers) 378 goto out_err; 379 version = program->version[args->version]; 380 if (version == NULL) 381 goto out_err; 382 383 err = -ENOMEM; 384 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); 385 if (!clnt) 386 goto out_err; 387 clnt->cl_parent = parent ? : clnt; 388 389 err = rpc_alloc_clid(clnt); 390 if (err) 391 goto out_no_clid; 392 393 clnt->cl_procinfo = version->procs; 394 clnt->cl_maxproc = version->nrprocs; 395 clnt->cl_prog = args->prognumber ? : program->number; 396 clnt->cl_vers = version->number; 397 clnt->cl_stats = program->stats; 398 clnt->cl_metrics = rpc_alloc_iostats(clnt); 399 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects); 400 err = -ENOMEM; 401 if (clnt->cl_metrics == NULL) 402 goto out_no_stats; 403 clnt->cl_program = program; 404 INIT_LIST_HEAD(&clnt->cl_tasks); 405 spin_lock_init(&clnt->cl_lock); 406 407 timeout = xprt->timeout; 408 if (args->timeout != NULL) { 409 memcpy(&clnt->cl_timeout_default, args->timeout, 410 sizeof(clnt->cl_timeout_default)); 411 timeout = &clnt->cl_timeout_default; 412 } 413 414 rpc_clnt_set_transport(clnt, xprt, timeout); 415 xprt_iter_init(&clnt->cl_xpi, xps); 416 xprt_switch_put(xps); 417 418 clnt->cl_rtt = &clnt->cl_rtt_default; 419 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval); 420 421 atomic_set(&clnt->cl_count, 1); 422 423 if (nodename == NULL) 424 nodename = utsname()->nodename; 425 /* save the nodename */ 426 rpc_clnt_set_nodename(clnt, nodename); 427 428 err = rpc_client_register(clnt, args->authflavor, args->client_name); 429 if (err) 430 goto out_no_path; 431 if (parent) 432 atomic_inc(&parent->cl_count); 433 return clnt; 434 435 out_no_path: 436 rpc_free_iostats(clnt->cl_metrics); 437 out_no_stats: 438 rpc_free_clid(clnt); 439 out_no_clid: 440 kfree(clnt); 441 out_err: 442 rpciod_down(); 443 out_no_rpciod: 444 xprt_switch_put(xps); 445 xprt_put(xprt); 446 return ERR_PTR(err); 447 } 448 449 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args, 450 struct rpc_xprt *xprt) 451 { 452 struct rpc_clnt *clnt = NULL; 453 struct rpc_xprt_switch *xps; 454 455 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) { 456 WARN_ON(args->protocol != XPRT_TRANSPORT_BC_TCP); 457 xps = args->bc_xprt->xpt_bc_xps; 458 xprt_switch_get(xps); 459 } else { 460 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 461 if (xps == NULL) { 462 xprt_put(xprt); 463 return ERR_PTR(-ENOMEM); 464 } 465 if (xprt->bc_xprt) { 466 xprt_switch_get(xps); 467 xprt->bc_xprt->xpt_bc_xps = xps; 468 } 469 } 470 clnt = rpc_new_client(args, xps, xprt, NULL); 471 if (IS_ERR(clnt)) 472 return clnt; 473 474 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) { 475 int err = rpc_ping(clnt); 476 if (err != 0) { 477 rpc_shutdown_client(clnt); 478 return ERR_PTR(err); 479 } 480 } 481 482 clnt->cl_softrtry = 1; 483 if (args->flags & RPC_CLNT_CREATE_HARDRTRY) 484 clnt->cl_softrtry = 0; 485 486 if (args->flags & RPC_CLNT_CREATE_AUTOBIND) 487 clnt->cl_autobind = 1; 488 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT) 489 clnt->cl_noretranstimeo = 1; 490 if (args->flags & RPC_CLNT_CREATE_DISCRTRY) 491 clnt->cl_discrtry = 1; 492 if (!(args->flags & RPC_CLNT_CREATE_QUIET)) 493 clnt->cl_chatty = 1; 494 495 return clnt; 496 } 497 498 /** 499 * rpc_create - create an RPC client and transport with one call 500 * @args: rpc_clnt create argument structure 501 * 502 * Creates and initializes an RPC transport and an RPC client. 503 * 504 * It can ping the server in order to determine if it is up, and to see if 505 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables 506 * this behavior so asynchronous tasks can also use rpc_create. 507 */ 508 struct rpc_clnt *rpc_create(struct rpc_create_args *args) 509 { 510 struct rpc_xprt *xprt; 511 struct xprt_create xprtargs = { 512 .net = args->net, 513 .ident = args->protocol, 514 .srcaddr = args->saddress, 515 .dstaddr = args->address, 516 .addrlen = args->addrsize, 517 .servername = args->servername, 518 .bc_xprt = args->bc_xprt, 519 }; 520 char servername[48]; 521 522 if (args->bc_xprt) { 523 WARN_ON(args->protocol != XPRT_TRANSPORT_BC_TCP); 524 xprt = args->bc_xprt->xpt_bc_xprt; 525 if (xprt) { 526 xprt_get(xprt); 527 return rpc_create_xprt(args, xprt); 528 } 529 } 530 531 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS) 532 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS; 533 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT) 534 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT; 535 /* 536 * If the caller chooses not to specify a hostname, whip 537 * up a string representation of the passed-in address. 538 */ 539 if (xprtargs.servername == NULL) { 540 struct sockaddr_un *sun = 541 (struct sockaddr_un *)args->address; 542 struct sockaddr_in *sin = 543 (struct sockaddr_in *)args->address; 544 struct sockaddr_in6 *sin6 = 545 (struct sockaddr_in6 *)args->address; 546 547 servername[0] = '\0'; 548 switch (args->address->sa_family) { 549 case AF_LOCAL: 550 snprintf(servername, sizeof(servername), "%s", 551 sun->sun_path); 552 break; 553 case AF_INET: 554 snprintf(servername, sizeof(servername), "%pI4", 555 &sin->sin_addr.s_addr); 556 break; 557 case AF_INET6: 558 snprintf(servername, sizeof(servername), "%pI6", 559 &sin6->sin6_addr); 560 break; 561 default: 562 /* caller wants default server name, but 563 * address family isn't recognized. */ 564 return ERR_PTR(-EINVAL); 565 } 566 xprtargs.servername = servername; 567 } 568 569 xprt = xprt_create_transport(&xprtargs); 570 if (IS_ERR(xprt)) 571 return (struct rpc_clnt *)xprt; 572 573 /* 574 * By default, kernel RPC client connects from a reserved port. 575 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters, 576 * but it is always enabled for rpciod, which handles the connect 577 * operation. 578 */ 579 xprt->resvport = 1; 580 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT) 581 xprt->resvport = 0; 582 583 return rpc_create_xprt(args, xprt); 584 } 585 EXPORT_SYMBOL_GPL(rpc_create); 586 587 /* 588 * This function clones the RPC client structure. It allows us to share the 589 * same transport while varying parameters such as the authentication 590 * flavour. 591 */ 592 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args, 593 struct rpc_clnt *clnt) 594 { 595 struct rpc_xprt_switch *xps; 596 struct rpc_xprt *xprt; 597 struct rpc_clnt *new; 598 int err; 599 600 err = -ENOMEM; 601 rcu_read_lock(); 602 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 603 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 604 rcu_read_unlock(); 605 if (xprt == NULL || xps == NULL) { 606 xprt_put(xprt); 607 xprt_switch_put(xps); 608 goto out_err; 609 } 610 args->servername = xprt->servername; 611 args->nodename = clnt->cl_nodename; 612 613 new = rpc_new_client(args, xps, xprt, clnt); 614 if (IS_ERR(new)) { 615 err = PTR_ERR(new); 616 goto out_err; 617 } 618 619 /* Turn off autobind on clones */ 620 new->cl_autobind = 0; 621 new->cl_softrtry = clnt->cl_softrtry; 622 new->cl_noretranstimeo = clnt->cl_noretranstimeo; 623 new->cl_discrtry = clnt->cl_discrtry; 624 new->cl_chatty = clnt->cl_chatty; 625 return new; 626 627 out_err: 628 dprintk("RPC: %s: returned error %d\n", __func__, err); 629 return ERR_PTR(err); 630 } 631 632 /** 633 * rpc_clone_client - Clone an RPC client structure 634 * 635 * @clnt: RPC client whose parameters are copied 636 * 637 * Returns a fresh RPC client or an ERR_PTR. 638 */ 639 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt) 640 { 641 struct rpc_create_args args = { 642 .program = clnt->cl_program, 643 .prognumber = clnt->cl_prog, 644 .version = clnt->cl_vers, 645 .authflavor = clnt->cl_auth->au_flavor, 646 }; 647 return __rpc_clone_client(&args, clnt); 648 } 649 EXPORT_SYMBOL_GPL(rpc_clone_client); 650 651 /** 652 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth 653 * 654 * @clnt: RPC client whose parameters are copied 655 * @flavor: security flavor for new client 656 * 657 * Returns a fresh RPC client or an ERR_PTR. 658 */ 659 struct rpc_clnt * 660 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor) 661 { 662 struct rpc_create_args args = { 663 .program = clnt->cl_program, 664 .prognumber = clnt->cl_prog, 665 .version = clnt->cl_vers, 666 .authflavor = flavor, 667 }; 668 return __rpc_clone_client(&args, clnt); 669 } 670 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth); 671 672 /** 673 * rpc_switch_client_transport: switch the RPC transport on the fly 674 * @clnt: pointer to a struct rpc_clnt 675 * @args: pointer to the new transport arguments 676 * @timeout: pointer to the new timeout parameters 677 * 678 * This function allows the caller to switch the RPC transport for the 679 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS 680 * server, for instance. It assumes that the caller has ensured that 681 * there are no active RPC tasks by using some form of locking. 682 * 683 * Returns zero if "clnt" is now using the new xprt. Otherwise a 684 * negative errno is returned, and "clnt" continues to use the old 685 * xprt. 686 */ 687 int rpc_switch_client_transport(struct rpc_clnt *clnt, 688 struct xprt_create *args, 689 const struct rpc_timeout *timeout) 690 { 691 const struct rpc_timeout *old_timeo; 692 rpc_authflavor_t pseudoflavor; 693 struct rpc_xprt_switch *xps, *oldxps; 694 struct rpc_xprt *xprt, *old; 695 struct rpc_clnt *parent; 696 int err; 697 698 xprt = xprt_create_transport(args); 699 if (IS_ERR(xprt)) { 700 dprintk("RPC: failed to create new xprt for clnt %p\n", 701 clnt); 702 return PTR_ERR(xprt); 703 } 704 705 xps = xprt_switch_alloc(xprt, GFP_KERNEL); 706 if (xps == NULL) { 707 xprt_put(xprt); 708 return -ENOMEM; 709 } 710 711 pseudoflavor = clnt->cl_auth->au_flavor; 712 713 old_timeo = clnt->cl_timeout; 714 old = rpc_clnt_set_transport(clnt, xprt, timeout); 715 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps); 716 717 rpc_unregister_client(clnt); 718 __rpc_clnt_remove_pipedir(clnt); 719 rpc_clnt_debugfs_unregister(clnt); 720 721 /* 722 * A new transport was created. "clnt" therefore 723 * becomes the root of a new cl_parent tree. clnt's 724 * children, if it has any, still point to the old xprt. 725 */ 726 parent = clnt->cl_parent; 727 clnt->cl_parent = clnt; 728 729 /* 730 * The old rpc_auth cache cannot be re-used. GSS 731 * contexts in particular are between a single 732 * client and server. 733 */ 734 err = rpc_client_register(clnt, pseudoflavor, NULL); 735 if (err) 736 goto out_revert; 737 738 synchronize_rcu(); 739 if (parent != clnt) 740 rpc_release_client(parent); 741 xprt_switch_put(oldxps); 742 xprt_put(old); 743 dprintk("RPC: replaced xprt for clnt %p\n", clnt); 744 return 0; 745 746 out_revert: 747 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps); 748 rpc_clnt_set_transport(clnt, old, old_timeo); 749 clnt->cl_parent = parent; 750 rpc_client_register(clnt, pseudoflavor, NULL); 751 xprt_switch_put(xps); 752 xprt_put(xprt); 753 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt); 754 return err; 755 } 756 EXPORT_SYMBOL_GPL(rpc_switch_client_transport); 757 758 static 759 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi) 760 { 761 struct rpc_xprt_switch *xps; 762 763 rcu_read_lock(); 764 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 765 rcu_read_unlock(); 766 if (xps == NULL) 767 return -EAGAIN; 768 xprt_iter_init_listall(xpi, xps); 769 xprt_switch_put(xps); 770 return 0; 771 } 772 773 /** 774 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports 775 * @clnt: pointer to client 776 * @fn: function to apply 777 * @data: void pointer to function data 778 * 779 * Iterates through the list of RPC transports currently attached to the 780 * client and applies the function fn(clnt, xprt, data). 781 * 782 * On error, the iteration stops, and the function returns the error value. 783 */ 784 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt, 785 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *), 786 void *data) 787 { 788 struct rpc_xprt_iter xpi; 789 int ret; 790 791 ret = rpc_clnt_xprt_iter_init(clnt, &xpi); 792 if (ret) 793 return ret; 794 for (;;) { 795 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi); 796 797 if (!xprt) 798 break; 799 ret = fn(clnt, xprt, data); 800 xprt_put(xprt); 801 if (ret < 0) 802 break; 803 } 804 xprt_iter_destroy(&xpi); 805 return ret; 806 } 807 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt); 808 809 /* 810 * Kill all tasks for the given client. 811 * XXX: kill their descendants as well? 812 */ 813 void rpc_killall_tasks(struct rpc_clnt *clnt) 814 { 815 struct rpc_task *rovr; 816 817 818 if (list_empty(&clnt->cl_tasks)) 819 return; 820 dprintk("RPC: killing all tasks for client %p\n", clnt); 821 /* 822 * Spin lock all_tasks to prevent changes... 823 */ 824 spin_lock(&clnt->cl_lock); 825 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) { 826 if (!RPC_IS_ACTIVATED(rovr)) 827 continue; 828 if (!(rovr->tk_flags & RPC_TASK_KILLED)) { 829 rovr->tk_flags |= RPC_TASK_KILLED; 830 rpc_exit(rovr, -EIO); 831 if (RPC_IS_QUEUED(rovr)) 832 rpc_wake_up_queued_task(rovr->tk_waitqueue, 833 rovr); 834 } 835 } 836 spin_unlock(&clnt->cl_lock); 837 } 838 EXPORT_SYMBOL_GPL(rpc_killall_tasks); 839 840 /* 841 * Properly shut down an RPC client, terminating all outstanding 842 * requests. 843 */ 844 void rpc_shutdown_client(struct rpc_clnt *clnt) 845 { 846 might_sleep(); 847 848 dprintk_rcu("RPC: shutting down %s client for %s\n", 849 clnt->cl_program->name, 850 rcu_dereference(clnt->cl_xprt)->servername); 851 852 while (!list_empty(&clnt->cl_tasks)) { 853 rpc_killall_tasks(clnt); 854 wait_event_timeout(destroy_wait, 855 list_empty(&clnt->cl_tasks), 1*HZ); 856 } 857 858 rpc_release_client(clnt); 859 } 860 EXPORT_SYMBOL_GPL(rpc_shutdown_client); 861 862 /* 863 * Free an RPC client 864 */ 865 static struct rpc_clnt * 866 rpc_free_client(struct rpc_clnt *clnt) 867 { 868 struct rpc_clnt *parent = NULL; 869 870 dprintk_rcu("RPC: destroying %s client for %s\n", 871 clnt->cl_program->name, 872 rcu_dereference(clnt->cl_xprt)->servername); 873 if (clnt->cl_parent != clnt) 874 parent = clnt->cl_parent; 875 rpc_clnt_debugfs_unregister(clnt); 876 rpc_clnt_remove_pipedir(clnt); 877 rpc_unregister_client(clnt); 878 rpc_free_iostats(clnt->cl_metrics); 879 clnt->cl_metrics = NULL; 880 xprt_put(rcu_dereference_raw(clnt->cl_xprt)); 881 xprt_iter_destroy(&clnt->cl_xpi); 882 rpciod_down(); 883 rpc_free_clid(clnt); 884 kfree(clnt); 885 return parent; 886 } 887 888 /* 889 * Free an RPC client 890 */ 891 static struct rpc_clnt * 892 rpc_free_auth(struct rpc_clnt *clnt) 893 { 894 if (clnt->cl_auth == NULL) 895 return rpc_free_client(clnt); 896 897 /* 898 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to 899 * release remaining GSS contexts. This mechanism ensures 900 * that it can do so safely. 901 */ 902 atomic_inc(&clnt->cl_count); 903 rpcauth_release(clnt->cl_auth); 904 clnt->cl_auth = NULL; 905 if (atomic_dec_and_test(&clnt->cl_count)) 906 return rpc_free_client(clnt); 907 return NULL; 908 } 909 910 /* 911 * Release reference to the RPC client 912 */ 913 void 914 rpc_release_client(struct rpc_clnt *clnt) 915 { 916 dprintk("RPC: rpc_release_client(%p)\n", clnt); 917 918 do { 919 if (list_empty(&clnt->cl_tasks)) 920 wake_up(&destroy_wait); 921 if (!atomic_dec_and_test(&clnt->cl_count)) 922 break; 923 clnt = rpc_free_auth(clnt); 924 } while (clnt != NULL); 925 } 926 EXPORT_SYMBOL_GPL(rpc_release_client); 927 928 /** 929 * rpc_bind_new_program - bind a new RPC program to an existing client 930 * @old: old rpc_client 931 * @program: rpc program to set 932 * @vers: rpc program version 933 * 934 * Clones the rpc client and sets up a new RPC program. This is mainly 935 * of use for enabling different RPC programs to share the same transport. 936 * The Sun NFSv2/v3 ACL protocol can do this. 937 */ 938 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 939 const struct rpc_program *program, 940 u32 vers) 941 { 942 struct rpc_create_args args = { 943 .program = program, 944 .prognumber = program->number, 945 .version = vers, 946 .authflavor = old->cl_auth->au_flavor, 947 }; 948 struct rpc_clnt *clnt; 949 int err; 950 951 clnt = __rpc_clone_client(&args, old); 952 if (IS_ERR(clnt)) 953 goto out; 954 err = rpc_ping(clnt); 955 if (err != 0) { 956 rpc_shutdown_client(clnt); 957 clnt = ERR_PTR(err); 958 } 959 out: 960 return clnt; 961 } 962 EXPORT_SYMBOL_GPL(rpc_bind_new_program); 963 964 void rpc_task_release_client(struct rpc_task *task) 965 { 966 struct rpc_clnt *clnt = task->tk_client; 967 struct rpc_xprt *xprt = task->tk_xprt; 968 969 if (clnt != NULL) { 970 /* Remove from client task list */ 971 spin_lock(&clnt->cl_lock); 972 list_del(&task->tk_task); 973 spin_unlock(&clnt->cl_lock); 974 task->tk_client = NULL; 975 976 rpc_release_client(clnt); 977 } 978 979 if (xprt != NULL) { 980 task->tk_xprt = NULL; 981 982 xprt_put(xprt); 983 } 984 } 985 986 static 987 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt) 988 { 989 990 if (clnt != NULL) { 991 rpc_task_release_client(task); 992 if (task->tk_xprt == NULL) 993 task->tk_xprt = xprt_iter_get_next(&clnt->cl_xpi); 994 task->tk_client = clnt; 995 atomic_inc(&clnt->cl_count); 996 if (clnt->cl_softrtry) 997 task->tk_flags |= RPC_TASK_SOFT; 998 if (clnt->cl_noretranstimeo) 999 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT; 1000 if (atomic_read(&clnt->cl_swapper)) 1001 task->tk_flags |= RPC_TASK_SWAPPER; 1002 /* Add to the client's list of all tasks */ 1003 spin_lock(&clnt->cl_lock); 1004 list_add_tail(&task->tk_task, &clnt->cl_tasks); 1005 spin_unlock(&clnt->cl_lock); 1006 } 1007 } 1008 1009 static void 1010 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg) 1011 { 1012 if (msg != NULL) { 1013 task->tk_msg.rpc_proc = msg->rpc_proc; 1014 task->tk_msg.rpc_argp = msg->rpc_argp; 1015 task->tk_msg.rpc_resp = msg->rpc_resp; 1016 if (msg->rpc_cred != NULL) 1017 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred); 1018 } 1019 } 1020 1021 /* 1022 * Default callback for async RPC calls 1023 */ 1024 static void 1025 rpc_default_callback(struct rpc_task *task, void *data) 1026 { 1027 } 1028 1029 static const struct rpc_call_ops rpc_default_ops = { 1030 .rpc_call_done = rpc_default_callback, 1031 }; 1032 1033 /** 1034 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it 1035 * @task_setup_data: pointer to task initialisation data 1036 */ 1037 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data) 1038 { 1039 struct rpc_task *task; 1040 1041 task = rpc_new_task(task_setup_data); 1042 if (IS_ERR(task)) 1043 goto out; 1044 1045 rpc_task_set_client(task, task_setup_data->rpc_client); 1046 rpc_task_set_rpc_message(task, task_setup_data->rpc_message); 1047 1048 if (task->tk_action == NULL) 1049 rpc_call_start(task); 1050 1051 atomic_inc(&task->tk_count); 1052 rpc_execute(task); 1053 out: 1054 return task; 1055 } 1056 EXPORT_SYMBOL_GPL(rpc_run_task); 1057 1058 /** 1059 * rpc_call_sync - Perform a synchronous RPC call 1060 * @clnt: pointer to RPC client 1061 * @msg: RPC call parameters 1062 * @flags: RPC call flags 1063 */ 1064 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags) 1065 { 1066 struct rpc_task *task; 1067 struct rpc_task_setup task_setup_data = { 1068 .rpc_client = clnt, 1069 .rpc_message = msg, 1070 .callback_ops = &rpc_default_ops, 1071 .flags = flags, 1072 }; 1073 int status; 1074 1075 WARN_ON_ONCE(flags & RPC_TASK_ASYNC); 1076 if (flags & RPC_TASK_ASYNC) { 1077 rpc_release_calldata(task_setup_data.callback_ops, 1078 task_setup_data.callback_data); 1079 return -EINVAL; 1080 } 1081 1082 task = rpc_run_task(&task_setup_data); 1083 if (IS_ERR(task)) 1084 return PTR_ERR(task); 1085 status = task->tk_status; 1086 rpc_put_task(task); 1087 return status; 1088 } 1089 EXPORT_SYMBOL_GPL(rpc_call_sync); 1090 1091 /** 1092 * rpc_call_async - Perform an asynchronous RPC call 1093 * @clnt: pointer to RPC client 1094 * @msg: RPC call parameters 1095 * @flags: RPC call flags 1096 * @tk_ops: RPC call ops 1097 * @data: user call data 1098 */ 1099 int 1100 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags, 1101 const struct rpc_call_ops *tk_ops, void *data) 1102 { 1103 struct rpc_task *task; 1104 struct rpc_task_setup task_setup_data = { 1105 .rpc_client = clnt, 1106 .rpc_message = msg, 1107 .callback_ops = tk_ops, 1108 .callback_data = data, 1109 .flags = flags|RPC_TASK_ASYNC, 1110 }; 1111 1112 task = rpc_run_task(&task_setup_data); 1113 if (IS_ERR(task)) 1114 return PTR_ERR(task); 1115 rpc_put_task(task); 1116 return 0; 1117 } 1118 EXPORT_SYMBOL_GPL(rpc_call_async); 1119 1120 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 1121 /** 1122 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run 1123 * rpc_execute against it 1124 * @req: RPC request 1125 */ 1126 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req) 1127 { 1128 struct rpc_task *task; 1129 struct xdr_buf *xbufp = &req->rq_snd_buf; 1130 struct rpc_task_setup task_setup_data = { 1131 .callback_ops = &rpc_default_ops, 1132 .flags = RPC_TASK_SOFTCONN, 1133 }; 1134 1135 dprintk("RPC: rpc_run_bc_task req= %p\n", req); 1136 /* 1137 * Create an rpc_task to send the data 1138 */ 1139 task = rpc_new_task(&task_setup_data); 1140 if (IS_ERR(task)) { 1141 xprt_free_bc_request(req); 1142 goto out; 1143 } 1144 task->tk_rqstp = req; 1145 1146 /* 1147 * Set up the xdr_buf length. 1148 * This also indicates that the buffer is XDR encoded already. 1149 */ 1150 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len + 1151 xbufp->tail[0].iov_len; 1152 1153 task->tk_action = call_bc_transmit; 1154 atomic_inc(&task->tk_count); 1155 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2); 1156 rpc_execute(task); 1157 1158 out: 1159 dprintk("RPC: rpc_run_bc_task: task= %p\n", task); 1160 return task; 1161 } 1162 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 1163 1164 void 1165 rpc_call_start(struct rpc_task *task) 1166 { 1167 task->tk_action = call_start; 1168 } 1169 EXPORT_SYMBOL_GPL(rpc_call_start); 1170 1171 /** 1172 * rpc_peeraddr - extract remote peer address from clnt's xprt 1173 * @clnt: RPC client structure 1174 * @buf: target buffer 1175 * @bufsize: length of target buffer 1176 * 1177 * Returns the number of bytes that are actually in the stored address. 1178 */ 1179 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize) 1180 { 1181 size_t bytes; 1182 struct rpc_xprt *xprt; 1183 1184 rcu_read_lock(); 1185 xprt = rcu_dereference(clnt->cl_xprt); 1186 1187 bytes = xprt->addrlen; 1188 if (bytes > bufsize) 1189 bytes = bufsize; 1190 memcpy(buf, &xprt->addr, bytes); 1191 rcu_read_unlock(); 1192 1193 return bytes; 1194 } 1195 EXPORT_SYMBOL_GPL(rpc_peeraddr); 1196 1197 /** 1198 * rpc_peeraddr2str - return remote peer address in printable format 1199 * @clnt: RPC client structure 1200 * @format: address format 1201 * 1202 * NB: the lifetime of the memory referenced by the returned pointer is 1203 * the same as the rpc_xprt itself. As long as the caller uses this 1204 * pointer, it must hold the RCU read lock. 1205 */ 1206 const char *rpc_peeraddr2str(struct rpc_clnt *clnt, 1207 enum rpc_display_format_t format) 1208 { 1209 struct rpc_xprt *xprt; 1210 1211 xprt = rcu_dereference(clnt->cl_xprt); 1212 1213 if (xprt->address_strings[format] != NULL) 1214 return xprt->address_strings[format]; 1215 else 1216 return "unprintable"; 1217 } 1218 EXPORT_SYMBOL_GPL(rpc_peeraddr2str); 1219 1220 static const struct sockaddr_in rpc_inaddr_loopback = { 1221 .sin_family = AF_INET, 1222 .sin_addr.s_addr = htonl(INADDR_ANY), 1223 }; 1224 1225 static const struct sockaddr_in6 rpc_in6addr_loopback = { 1226 .sin6_family = AF_INET6, 1227 .sin6_addr = IN6ADDR_ANY_INIT, 1228 }; 1229 1230 /* 1231 * Try a getsockname() on a connected datagram socket. Using a 1232 * connected datagram socket prevents leaving a socket in TIME_WAIT. 1233 * This conserves the ephemeral port number space. 1234 * 1235 * Returns zero and fills in "buf" if successful; otherwise, a 1236 * negative errno is returned. 1237 */ 1238 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen, 1239 struct sockaddr *buf, int buflen) 1240 { 1241 struct socket *sock; 1242 int err; 1243 1244 err = __sock_create(net, sap->sa_family, 1245 SOCK_DGRAM, IPPROTO_UDP, &sock, 1); 1246 if (err < 0) { 1247 dprintk("RPC: can't create UDP socket (%d)\n", err); 1248 goto out; 1249 } 1250 1251 switch (sap->sa_family) { 1252 case AF_INET: 1253 err = kernel_bind(sock, 1254 (struct sockaddr *)&rpc_inaddr_loopback, 1255 sizeof(rpc_inaddr_loopback)); 1256 break; 1257 case AF_INET6: 1258 err = kernel_bind(sock, 1259 (struct sockaddr *)&rpc_in6addr_loopback, 1260 sizeof(rpc_in6addr_loopback)); 1261 break; 1262 default: 1263 err = -EAFNOSUPPORT; 1264 goto out; 1265 } 1266 if (err < 0) { 1267 dprintk("RPC: can't bind UDP socket (%d)\n", err); 1268 goto out_release; 1269 } 1270 1271 err = kernel_connect(sock, sap, salen, 0); 1272 if (err < 0) { 1273 dprintk("RPC: can't connect UDP socket (%d)\n", err); 1274 goto out_release; 1275 } 1276 1277 err = kernel_getsockname(sock, buf, &buflen); 1278 if (err < 0) { 1279 dprintk("RPC: getsockname failed (%d)\n", err); 1280 goto out_release; 1281 } 1282 1283 err = 0; 1284 if (buf->sa_family == AF_INET6) { 1285 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf; 1286 sin6->sin6_scope_id = 0; 1287 } 1288 dprintk("RPC: %s succeeded\n", __func__); 1289 1290 out_release: 1291 sock_release(sock); 1292 out: 1293 return err; 1294 } 1295 1296 /* 1297 * Scraping a connected socket failed, so we don't have a useable 1298 * local address. Fallback: generate an address that will prevent 1299 * the server from calling us back. 1300 * 1301 * Returns zero and fills in "buf" if successful; otherwise, a 1302 * negative errno is returned. 1303 */ 1304 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen) 1305 { 1306 switch (family) { 1307 case AF_INET: 1308 if (buflen < sizeof(rpc_inaddr_loopback)) 1309 return -EINVAL; 1310 memcpy(buf, &rpc_inaddr_loopback, 1311 sizeof(rpc_inaddr_loopback)); 1312 break; 1313 case AF_INET6: 1314 if (buflen < sizeof(rpc_in6addr_loopback)) 1315 return -EINVAL; 1316 memcpy(buf, &rpc_in6addr_loopback, 1317 sizeof(rpc_in6addr_loopback)); 1318 break; 1319 default: 1320 dprintk("RPC: %s: address family not supported\n", 1321 __func__); 1322 return -EAFNOSUPPORT; 1323 } 1324 dprintk("RPC: %s: succeeded\n", __func__); 1325 return 0; 1326 } 1327 1328 /** 1329 * rpc_localaddr - discover local endpoint address for an RPC client 1330 * @clnt: RPC client structure 1331 * @buf: target buffer 1332 * @buflen: size of target buffer, in bytes 1333 * 1334 * Returns zero and fills in "buf" and "buflen" if successful; 1335 * otherwise, a negative errno is returned. 1336 * 1337 * This works even if the underlying transport is not currently connected, 1338 * or if the upper layer never previously provided a source address. 1339 * 1340 * The result of this function call is transient: multiple calls in 1341 * succession may give different results, depending on how local 1342 * networking configuration changes over time. 1343 */ 1344 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen) 1345 { 1346 struct sockaddr_storage address; 1347 struct sockaddr *sap = (struct sockaddr *)&address; 1348 struct rpc_xprt *xprt; 1349 struct net *net; 1350 size_t salen; 1351 int err; 1352 1353 rcu_read_lock(); 1354 xprt = rcu_dereference(clnt->cl_xprt); 1355 salen = xprt->addrlen; 1356 memcpy(sap, &xprt->addr, salen); 1357 net = get_net(xprt->xprt_net); 1358 rcu_read_unlock(); 1359 1360 rpc_set_port(sap, 0); 1361 err = rpc_sockname(net, sap, salen, buf, buflen); 1362 put_net(net); 1363 if (err != 0) 1364 /* Couldn't discover local address, return ANYADDR */ 1365 return rpc_anyaddr(sap->sa_family, buf, buflen); 1366 return 0; 1367 } 1368 EXPORT_SYMBOL_GPL(rpc_localaddr); 1369 1370 void 1371 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 1372 { 1373 struct rpc_xprt *xprt; 1374 1375 rcu_read_lock(); 1376 xprt = rcu_dereference(clnt->cl_xprt); 1377 if (xprt->ops->set_buffer_size) 1378 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize); 1379 rcu_read_unlock(); 1380 } 1381 EXPORT_SYMBOL_GPL(rpc_setbufsize); 1382 1383 /** 1384 * rpc_protocol - Get transport protocol number for an RPC client 1385 * @clnt: RPC client to query 1386 * 1387 */ 1388 int rpc_protocol(struct rpc_clnt *clnt) 1389 { 1390 int protocol; 1391 1392 rcu_read_lock(); 1393 protocol = rcu_dereference(clnt->cl_xprt)->prot; 1394 rcu_read_unlock(); 1395 return protocol; 1396 } 1397 EXPORT_SYMBOL_GPL(rpc_protocol); 1398 1399 /** 1400 * rpc_net_ns - Get the network namespace for this RPC client 1401 * @clnt: RPC client to query 1402 * 1403 */ 1404 struct net *rpc_net_ns(struct rpc_clnt *clnt) 1405 { 1406 struct net *ret; 1407 1408 rcu_read_lock(); 1409 ret = rcu_dereference(clnt->cl_xprt)->xprt_net; 1410 rcu_read_unlock(); 1411 return ret; 1412 } 1413 EXPORT_SYMBOL_GPL(rpc_net_ns); 1414 1415 /** 1416 * rpc_max_payload - Get maximum payload size for a transport, in bytes 1417 * @clnt: RPC client to query 1418 * 1419 * For stream transports, this is one RPC record fragment (see RFC 1420 * 1831), as we don't support multi-record requests yet. For datagram 1421 * transports, this is the size of an IP packet minus the IP, UDP, and 1422 * RPC header sizes. 1423 */ 1424 size_t rpc_max_payload(struct rpc_clnt *clnt) 1425 { 1426 size_t ret; 1427 1428 rcu_read_lock(); 1429 ret = rcu_dereference(clnt->cl_xprt)->max_payload; 1430 rcu_read_unlock(); 1431 return ret; 1432 } 1433 EXPORT_SYMBOL_GPL(rpc_max_payload); 1434 1435 /** 1436 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes 1437 * @clnt: RPC client to query 1438 */ 1439 size_t rpc_max_bc_payload(struct rpc_clnt *clnt) 1440 { 1441 struct rpc_xprt *xprt; 1442 size_t ret; 1443 1444 rcu_read_lock(); 1445 xprt = rcu_dereference(clnt->cl_xprt); 1446 ret = xprt->ops->bc_maxpayload(xprt); 1447 rcu_read_unlock(); 1448 return ret; 1449 } 1450 EXPORT_SYMBOL_GPL(rpc_max_bc_payload); 1451 1452 /** 1453 * rpc_get_timeout - Get timeout for transport in units of HZ 1454 * @clnt: RPC client to query 1455 */ 1456 unsigned long rpc_get_timeout(struct rpc_clnt *clnt) 1457 { 1458 unsigned long ret; 1459 1460 rcu_read_lock(); 1461 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval; 1462 rcu_read_unlock(); 1463 return ret; 1464 } 1465 EXPORT_SYMBOL_GPL(rpc_get_timeout); 1466 1467 /** 1468 * rpc_force_rebind - force transport to check that remote port is unchanged 1469 * @clnt: client to rebind 1470 * 1471 */ 1472 void rpc_force_rebind(struct rpc_clnt *clnt) 1473 { 1474 if (clnt->cl_autobind) { 1475 rcu_read_lock(); 1476 xprt_clear_bound(rcu_dereference(clnt->cl_xprt)); 1477 rcu_read_unlock(); 1478 } 1479 } 1480 EXPORT_SYMBOL_GPL(rpc_force_rebind); 1481 1482 /* 1483 * Restart an (async) RPC call from the call_prepare state. 1484 * Usually called from within the exit handler. 1485 */ 1486 int 1487 rpc_restart_call_prepare(struct rpc_task *task) 1488 { 1489 if (RPC_ASSASSINATED(task)) 1490 return 0; 1491 task->tk_action = call_start; 1492 task->tk_status = 0; 1493 if (task->tk_ops->rpc_call_prepare != NULL) 1494 task->tk_action = rpc_prepare_task; 1495 return 1; 1496 } 1497 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare); 1498 1499 /* 1500 * Restart an (async) RPC call. Usually called from within the 1501 * exit handler. 1502 */ 1503 int 1504 rpc_restart_call(struct rpc_task *task) 1505 { 1506 if (RPC_ASSASSINATED(task)) 1507 return 0; 1508 task->tk_action = call_start; 1509 task->tk_status = 0; 1510 return 1; 1511 } 1512 EXPORT_SYMBOL_GPL(rpc_restart_call); 1513 1514 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 1515 const char 1516 *rpc_proc_name(const struct rpc_task *task) 1517 { 1518 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1519 1520 if (proc) { 1521 if (proc->p_name) 1522 return proc->p_name; 1523 else 1524 return "NULL"; 1525 } else 1526 return "no proc"; 1527 } 1528 #endif 1529 1530 /* 1531 * 0. Initial state 1532 * 1533 * Other FSM states can be visited zero or more times, but 1534 * this state is visited exactly once for each RPC. 1535 */ 1536 static void 1537 call_start(struct rpc_task *task) 1538 { 1539 struct rpc_clnt *clnt = task->tk_client; 1540 1541 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid, 1542 clnt->cl_program->name, clnt->cl_vers, 1543 rpc_proc_name(task), 1544 (RPC_IS_ASYNC(task) ? "async" : "sync")); 1545 1546 /* Increment call count */ 1547 task->tk_msg.rpc_proc->p_count++; 1548 clnt->cl_stats->rpccnt++; 1549 task->tk_action = call_reserve; 1550 } 1551 1552 /* 1553 * 1. Reserve an RPC call slot 1554 */ 1555 static void 1556 call_reserve(struct rpc_task *task) 1557 { 1558 dprint_status(task); 1559 1560 task->tk_status = 0; 1561 task->tk_action = call_reserveresult; 1562 xprt_reserve(task); 1563 } 1564 1565 static void call_retry_reserve(struct rpc_task *task); 1566 1567 /* 1568 * 1b. Grok the result of xprt_reserve() 1569 */ 1570 static void 1571 call_reserveresult(struct rpc_task *task) 1572 { 1573 int status = task->tk_status; 1574 1575 dprint_status(task); 1576 1577 /* 1578 * After a call to xprt_reserve(), we must have either 1579 * a request slot or else an error status. 1580 */ 1581 task->tk_status = 0; 1582 if (status >= 0) { 1583 if (task->tk_rqstp) { 1584 task->tk_action = call_refresh; 1585 return; 1586 } 1587 1588 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 1589 __func__, status); 1590 rpc_exit(task, -EIO); 1591 return; 1592 } 1593 1594 /* 1595 * Even though there was an error, we may have acquired 1596 * a request slot somehow. Make sure not to leak it. 1597 */ 1598 if (task->tk_rqstp) { 1599 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 1600 __func__, status); 1601 xprt_release(task); 1602 } 1603 1604 switch (status) { 1605 case -ENOMEM: 1606 rpc_delay(task, HZ >> 2); 1607 case -EAGAIN: /* woken up; retry */ 1608 task->tk_action = call_retry_reserve; 1609 return; 1610 case -EIO: /* probably a shutdown */ 1611 break; 1612 default: 1613 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 1614 __func__, status); 1615 break; 1616 } 1617 rpc_exit(task, status); 1618 } 1619 1620 /* 1621 * 1c. Retry reserving an RPC call slot 1622 */ 1623 static void 1624 call_retry_reserve(struct rpc_task *task) 1625 { 1626 dprint_status(task); 1627 1628 task->tk_status = 0; 1629 task->tk_action = call_reserveresult; 1630 xprt_retry_reserve(task); 1631 } 1632 1633 /* 1634 * 2. Bind and/or refresh the credentials 1635 */ 1636 static void 1637 call_refresh(struct rpc_task *task) 1638 { 1639 dprint_status(task); 1640 1641 task->tk_action = call_refreshresult; 1642 task->tk_status = 0; 1643 task->tk_client->cl_stats->rpcauthrefresh++; 1644 rpcauth_refreshcred(task); 1645 } 1646 1647 /* 1648 * 2a. Process the results of a credential refresh 1649 */ 1650 static void 1651 call_refreshresult(struct rpc_task *task) 1652 { 1653 int status = task->tk_status; 1654 1655 dprint_status(task); 1656 1657 task->tk_status = 0; 1658 task->tk_action = call_refresh; 1659 switch (status) { 1660 case 0: 1661 if (rpcauth_uptodatecred(task)) { 1662 task->tk_action = call_allocate; 1663 return; 1664 } 1665 /* Use rate-limiting and a max number of retries if refresh 1666 * had status 0 but failed to update the cred. 1667 */ 1668 case -ETIMEDOUT: 1669 rpc_delay(task, 3*HZ); 1670 case -EAGAIN: 1671 status = -EACCES; 1672 case -EKEYEXPIRED: 1673 if (!task->tk_cred_retry) 1674 break; 1675 task->tk_cred_retry--; 1676 dprintk("RPC: %5u %s: retry refresh creds\n", 1677 task->tk_pid, __func__); 1678 return; 1679 } 1680 dprintk("RPC: %5u %s: refresh creds failed with error %d\n", 1681 task->tk_pid, __func__, status); 1682 rpc_exit(task, status); 1683 } 1684 1685 /* 1686 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc. 1687 * (Note: buffer memory is freed in xprt_release). 1688 */ 1689 static void 1690 call_allocate(struct rpc_task *task) 1691 { 1692 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack; 1693 struct rpc_rqst *req = task->tk_rqstp; 1694 struct rpc_xprt *xprt = req->rq_xprt; 1695 struct rpc_procinfo *proc = task->tk_msg.rpc_proc; 1696 1697 dprint_status(task); 1698 1699 task->tk_status = 0; 1700 task->tk_action = call_bind; 1701 1702 if (req->rq_buffer) 1703 return; 1704 1705 if (proc->p_proc != 0) { 1706 BUG_ON(proc->p_arglen == 0); 1707 if (proc->p_decode != NULL) 1708 BUG_ON(proc->p_replen == 0); 1709 } 1710 1711 /* 1712 * Calculate the size (in quads) of the RPC call 1713 * and reply headers, and convert both values 1714 * to byte sizes. 1715 */ 1716 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen; 1717 req->rq_callsize <<= 2; 1718 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen; 1719 req->rq_rcvsize <<= 2; 1720 1721 req->rq_buffer = xprt->ops->buf_alloc(task, 1722 req->rq_callsize + req->rq_rcvsize); 1723 if (req->rq_buffer != NULL) 1724 return; 1725 xprt_inject_disconnect(xprt); 1726 1727 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid); 1728 1729 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) { 1730 task->tk_action = call_allocate; 1731 rpc_delay(task, HZ>>4); 1732 return; 1733 } 1734 1735 rpc_exit(task, -ERESTARTSYS); 1736 } 1737 1738 static inline int 1739 rpc_task_need_encode(struct rpc_task *task) 1740 { 1741 return task->tk_rqstp->rq_snd_buf.len == 0; 1742 } 1743 1744 static inline void 1745 rpc_task_force_reencode(struct rpc_task *task) 1746 { 1747 task->tk_rqstp->rq_snd_buf.len = 0; 1748 task->tk_rqstp->rq_bytes_sent = 0; 1749 } 1750 1751 static inline void 1752 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 1753 { 1754 buf->head[0].iov_base = start; 1755 buf->head[0].iov_len = len; 1756 buf->tail[0].iov_len = 0; 1757 buf->page_len = 0; 1758 buf->flags = 0; 1759 buf->len = 0; 1760 buf->buflen = len; 1761 } 1762 1763 /* 1764 * 3. Encode arguments of an RPC call 1765 */ 1766 static void 1767 rpc_xdr_encode(struct rpc_task *task) 1768 { 1769 struct rpc_rqst *req = task->tk_rqstp; 1770 kxdreproc_t encode; 1771 __be32 *p; 1772 1773 dprint_status(task); 1774 1775 rpc_xdr_buf_init(&req->rq_snd_buf, 1776 req->rq_buffer, 1777 req->rq_callsize); 1778 rpc_xdr_buf_init(&req->rq_rcv_buf, 1779 (char *)req->rq_buffer + req->rq_callsize, 1780 req->rq_rcvsize); 1781 1782 p = rpc_encode_header(task); 1783 if (p == NULL) { 1784 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n"); 1785 rpc_exit(task, -EIO); 1786 return; 1787 } 1788 1789 encode = task->tk_msg.rpc_proc->p_encode; 1790 if (encode == NULL) 1791 return; 1792 1793 task->tk_status = rpcauth_wrap_req(task, encode, req, p, 1794 task->tk_msg.rpc_argp); 1795 } 1796 1797 /* 1798 * 4. Get the server port number if not yet set 1799 */ 1800 static void 1801 call_bind(struct rpc_task *task) 1802 { 1803 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1804 1805 dprint_status(task); 1806 1807 task->tk_action = call_connect; 1808 if (!xprt_bound(xprt)) { 1809 task->tk_action = call_bind_status; 1810 task->tk_timeout = xprt->bind_timeout; 1811 xprt->ops->rpcbind(task); 1812 } 1813 } 1814 1815 /* 1816 * 4a. Sort out bind result 1817 */ 1818 static void 1819 call_bind_status(struct rpc_task *task) 1820 { 1821 int status = -EIO; 1822 1823 if (task->tk_status >= 0) { 1824 dprint_status(task); 1825 task->tk_status = 0; 1826 task->tk_action = call_connect; 1827 return; 1828 } 1829 1830 trace_rpc_bind_status(task); 1831 switch (task->tk_status) { 1832 case -ENOMEM: 1833 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid); 1834 rpc_delay(task, HZ >> 2); 1835 goto retry_timeout; 1836 case -EACCES: 1837 dprintk("RPC: %5u remote rpcbind: RPC program/version " 1838 "unavailable\n", task->tk_pid); 1839 /* fail immediately if this is an RPC ping */ 1840 if (task->tk_msg.rpc_proc->p_proc == 0) { 1841 status = -EOPNOTSUPP; 1842 break; 1843 } 1844 if (task->tk_rebind_retry == 0) 1845 break; 1846 task->tk_rebind_retry--; 1847 rpc_delay(task, 3*HZ); 1848 goto retry_timeout; 1849 case -ETIMEDOUT: 1850 dprintk("RPC: %5u rpcbind request timed out\n", 1851 task->tk_pid); 1852 goto retry_timeout; 1853 case -EPFNOSUPPORT: 1854 /* server doesn't support any rpcbind version we know of */ 1855 dprintk("RPC: %5u unrecognized remote rpcbind service\n", 1856 task->tk_pid); 1857 break; 1858 case -EPROTONOSUPPORT: 1859 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n", 1860 task->tk_pid); 1861 goto retry_timeout; 1862 case -ECONNREFUSED: /* connection problems */ 1863 case -ECONNRESET: 1864 case -ECONNABORTED: 1865 case -ENOTCONN: 1866 case -EHOSTDOWN: 1867 case -EHOSTUNREACH: 1868 case -ENETUNREACH: 1869 case -ENOBUFS: 1870 case -EPIPE: 1871 dprintk("RPC: %5u remote rpcbind unreachable: %d\n", 1872 task->tk_pid, task->tk_status); 1873 if (!RPC_IS_SOFTCONN(task)) { 1874 rpc_delay(task, 5*HZ); 1875 goto retry_timeout; 1876 } 1877 status = task->tk_status; 1878 break; 1879 default: 1880 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n", 1881 task->tk_pid, -task->tk_status); 1882 } 1883 1884 rpc_exit(task, status); 1885 return; 1886 1887 retry_timeout: 1888 task->tk_status = 0; 1889 task->tk_action = call_timeout; 1890 } 1891 1892 /* 1893 * 4b. Connect to the RPC server 1894 */ 1895 static void 1896 call_connect(struct rpc_task *task) 1897 { 1898 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; 1899 1900 dprintk("RPC: %5u call_connect xprt %p %s connected\n", 1901 task->tk_pid, xprt, 1902 (xprt_connected(xprt) ? "is" : "is not")); 1903 1904 task->tk_action = call_transmit; 1905 if (!xprt_connected(xprt)) { 1906 task->tk_action = call_connect_status; 1907 if (task->tk_status < 0) 1908 return; 1909 if (task->tk_flags & RPC_TASK_NOCONNECT) { 1910 rpc_exit(task, -ENOTCONN); 1911 return; 1912 } 1913 xprt_connect(task); 1914 } 1915 } 1916 1917 /* 1918 * 4c. Sort out connect result 1919 */ 1920 static void 1921 call_connect_status(struct rpc_task *task) 1922 { 1923 struct rpc_clnt *clnt = task->tk_client; 1924 int status = task->tk_status; 1925 1926 dprint_status(task); 1927 1928 trace_rpc_connect_status(task, status); 1929 task->tk_status = 0; 1930 switch (status) { 1931 case -ECONNREFUSED: 1932 case -ECONNRESET: 1933 case -ECONNABORTED: 1934 case -ENETUNREACH: 1935 case -EHOSTUNREACH: 1936 case -EADDRINUSE: 1937 case -ENOBUFS: 1938 case -EPIPE: 1939 if (RPC_IS_SOFTCONN(task)) 1940 break; 1941 /* retry with existing socket, after a delay */ 1942 rpc_delay(task, 3*HZ); 1943 case -EAGAIN: 1944 /* Check for timeouts before looping back to call_bind */ 1945 case -ETIMEDOUT: 1946 task->tk_action = call_timeout; 1947 return; 1948 case 0: 1949 clnt->cl_stats->netreconn++; 1950 task->tk_action = call_transmit; 1951 return; 1952 } 1953 rpc_exit(task, status); 1954 } 1955 1956 /* 1957 * 5. Transmit the RPC request, and wait for reply 1958 */ 1959 static void 1960 call_transmit(struct rpc_task *task) 1961 { 1962 int is_retrans = RPC_WAS_SENT(task); 1963 1964 dprint_status(task); 1965 1966 task->tk_action = call_status; 1967 if (task->tk_status < 0) 1968 return; 1969 if (!xprt_prepare_transmit(task)) 1970 return; 1971 task->tk_action = call_transmit_status; 1972 /* Encode here so that rpcsec_gss can use correct sequence number. */ 1973 if (rpc_task_need_encode(task)) { 1974 rpc_xdr_encode(task); 1975 /* Did the encode result in an error condition? */ 1976 if (task->tk_status != 0) { 1977 /* Was the error nonfatal? */ 1978 if (task->tk_status == -EAGAIN) 1979 rpc_delay(task, HZ >> 4); 1980 else 1981 rpc_exit(task, task->tk_status); 1982 return; 1983 } 1984 } 1985 xprt_transmit(task); 1986 if (task->tk_status < 0) 1987 return; 1988 if (is_retrans) 1989 task->tk_client->cl_stats->rpcretrans++; 1990 /* 1991 * On success, ensure that we call xprt_end_transmit() before sleeping 1992 * in order to allow access to the socket to other RPC requests. 1993 */ 1994 call_transmit_status(task); 1995 if (rpc_reply_expected(task)) 1996 return; 1997 task->tk_action = rpc_exit_task; 1998 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task); 1999 } 2000 2001 /* 2002 * 5a. Handle cleanup after a transmission 2003 */ 2004 static void 2005 call_transmit_status(struct rpc_task *task) 2006 { 2007 task->tk_action = call_status; 2008 2009 /* 2010 * Common case: success. Force the compiler to put this 2011 * test first. 2012 */ 2013 if (task->tk_status == 0) { 2014 xprt_end_transmit(task); 2015 rpc_task_force_reencode(task); 2016 return; 2017 } 2018 2019 switch (task->tk_status) { 2020 case -EAGAIN: 2021 case -ENOBUFS: 2022 break; 2023 default: 2024 dprint_status(task); 2025 xprt_end_transmit(task); 2026 rpc_task_force_reencode(task); 2027 break; 2028 /* 2029 * Special cases: if we've been waiting on the 2030 * socket's write_space() callback, or if the 2031 * socket just returned a connection error, 2032 * then hold onto the transport lock. 2033 */ 2034 case -ECONNREFUSED: 2035 case -EHOSTDOWN: 2036 case -EHOSTUNREACH: 2037 case -ENETUNREACH: 2038 case -EPERM: 2039 if (RPC_IS_SOFTCONN(task)) { 2040 xprt_end_transmit(task); 2041 rpc_exit(task, task->tk_status); 2042 break; 2043 } 2044 case -ECONNRESET: 2045 case -ECONNABORTED: 2046 case -EADDRINUSE: 2047 case -ENOTCONN: 2048 case -EPIPE: 2049 rpc_task_force_reencode(task); 2050 } 2051 } 2052 2053 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 2054 /* 2055 * 5b. Send the backchannel RPC reply. On error, drop the reply. In 2056 * addition, disconnect on connectivity errors. 2057 */ 2058 static void 2059 call_bc_transmit(struct rpc_task *task) 2060 { 2061 struct rpc_rqst *req = task->tk_rqstp; 2062 2063 if (!xprt_prepare_transmit(task)) 2064 goto out_retry; 2065 2066 if (task->tk_status < 0) { 2067 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2068 "error: %d\n", task->tk_status); 2069 goto out_done; 2070 } 2071 if (req->rq_connect_cookie != req->rq_xprt->connect_cookie) 2072 req->rq_bytes_sent = 0; 2073 2074 xprt_transmit(task); 2075 2076 if (task->tk_status == -EAGAIN) 2077 goto out_nospace; 2078 2079 xprt_end_transmit(task); 2080 dprint_status(task); 2081 switch (task->tk_status) { 2082 case 0: 2083 /* Success */ 2084 case -EHOSTDOWN: 2085 case -EHOSTUNREACH: 2086 case -ENETUNREACH: 2087 case -ECONNRESET: 2088 case -ECONNREFUSED: 2089 case -EADDRINUSE: 2090 case -ENOTCONN: 2091 case -EPIPE: 2092 break; 2093 case -ETIMEDOUT: 2094 /* 2095 * Problem reaching the server. Disconnect and let the 2096 * forechannel reestablish the connection. The server will 2097 * have to retransmit the backchannel request and we'll 2098 * reprocess it. Since these ops are idempotent, there's no 2099 * need to cache our reply at this time. 2100 */ 2101 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2102 "error: %d\n", task->tk_status); 2103 xprt_conditional_disconnect(req->rq_xprt, 2104 req->rq_connect_cookie); 2105 break; 2106 default: 2107 /* 2108 * We were unable to reply and will have to drop the 2109 * request. The server should reconnect and retransmit. 2110 */ 2111 WARN_ON_ONCE(task->tk_status == -EAGAIN); 2112 printk(KERN_NOTICE "RPC: Could not send backchannel reply " 2113 "error: %d\n", task->tk_status); 2114 break; 2115 } 2116 rpc_wake_up_queued_task(&req->rq_xprt->pending, task); 2117 out_done: 2118 task->tk_action = rpc_exit_task; 2119 return; 2120 out_nospace: 2121 req->rq_connect_cookie = req->rq_xprt->connect_cookie; 2122 out_retry: 2123 task->tk_status = 0; 2124 } 2125 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 2126 2127 /* 2128 * 6. Sort out the RPC call status 2129 */ 2130 static void 2131 call_status(struct rpc_task *task) 2132 { 2133 struct rpc_clnt *clnt = task->tk_client; 2134 struct rpc_rqst *req = task->tk_rqstp; 2135 int status; 2136 2137 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent) 2138 task->tk_status = req->rq_reply_bytes_recvd; 2139 2140 dprint_status(task); 2141 2142 status = task->tk_status; 2143 if (status >= 0) { 2144 task->tk_action = call_decode; 2145 return; 2146 } 2147 2148 trace_rpc_call_status(task); 2149 task->tk_status = 0; 2150 switch(status) { 2151 case -EHOSTDOWN: 2152 case -EHOSTUNREACH: 2153 case -ENETUNREACH: 2154 case -EPERM: 2155 if (RPC_IS_SOFTCONN(task)) { 2156 rpc_exit(task, status); 2157 break; 2158 } 2159 /* 2160 * Delay any retries for 3 seconds, then handle as if it 2161 * were a timeout. 2162 */ 2163 rpc_delay(task, 3*HZ); 2164 case -ETIMEDOUT: 2165 task->tk_action = call_timeout; 2166 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) 2167 && task->tk_client->cl_discrtry) 2168 xprt_conditional_disconnect(req->rq_xprt, 2169 req->rq_connect_cookie); 2170 break; 2171 case -ECONNREFUSED: 2172 case -ECONNRESET: 2173 case -ECONNABORTED: 2174 rpc_force_rebind(clnt); 2175 case -EADDRINUSE: 2176 rpc_delay(task, 3*HZ); 2177 case -EPIPE: 2178 case -ENOTCONN: 2179 task->tk_action = call_bind; 2180 break; 2181 case -ENOBUFS: 2182 rpc_delay(task, HZ>>2); 2183 case -EAGAIN: 2184 task->tk_action = call_transmit; 2185 break; 2186 case -EIO: 2187 /* shutdown or soft timeout */ 2188 rpc_exit(task, status); 2189 break; 2190 default: 2191 if (clnt->cl_chatty) 2192 printk("%s: RPC call returned error %d\n", 2193 clnt->cl_program->name, -status); 2194 rpc_exit(task, status); 2195 } 2196 } 2197 2198 /* 2199 * 6a. Handle RPC timeout 2200 * We do not release the request slot, so we keep using the 2201 * same XID for all retransmits. 2202 */ 2203 static void 2204 call_timeout(struct rpc_task *task) 2205 { 2206 struct rpc_clnt *clnt = task->tk_client; 2207 2208 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 2209 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid); 2210 goto retry; 2211 } 2212 2213 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid); 2214 task->tk_timeouts++; 2215 2216 if (RPC_IS_SOFTCONN(task)) { 2217 rpc_exit(task, -ETIMEDOUT); 2218 return; 2219 } 2220 if (RPC_IS_SOFT(task)) { 2221 if (clnt->cl_chatty) { 2222 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 2223 clnt->cl_program->name, 2224 task->tk_xprt->servername); 2225 } 2226 if (task->tk_flags & RPC_TASK_TIMEOUT) 2227 rpc_exit(task, -ETIMEDOUT); 2228 else 2229 rpc_exit(task, -EIO); 2230 return; 2231 } 2232 2233 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) { 2234 task->tk_flags |= RPC_CALL_MAJORSEEN; 2235 if (clnt->cl_chatty) { 2236 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 2237 clnt->cl_program->name, 2238 task->tk_xprt->servername); 2239 } 2240 } 2241 rpc_force_rebind(clnt); 2242 /* 2243 * Did our request time out due to an RPCSEC_GSS out-of-sequence 2244 * event? RFC2203 requires the server to drop all such requests. 2245 */ 2246 rpcauth_invalcred(task); 2247 2248 retry: 2249 task->tk_action = call_bind; 2250 task->tk_status = 0; 2251 } 2252 2253 /* 2254 * 7. Decode the RPC reply 2255 */ 2256 static void 2257 call_decode(struct rpc_task *task) 2258 { 2259 struct rpc_clnt *clnt = task->tk_client; 2260 struct rpc_rqst *req = task->tk_rqstp; 2261 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode; 2262 __be32 *p; 2263 2264 dprint_status(task); 2265 2266 if (task->tk_flags & RPC_CALL_MAJORSEEN) { 2267 if (clnt->cl_chatty) { 2268 printk(KERN_NOTICE "%s: server %s OK\n", 2269 clnt->cl_program->name, 2270 task->tk_xprt->servername); 2271 } 2272 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 2273 } 2274 2275 /* 2276 * Ensure that we see all writes made by xprt_complete_rqst() 2277 * before it changed req->rq_reply_bytes_recvd. 2278 */ 2279 smp_rmb(); 2280 req->rq_rcv_buf.len = req->rq_private_buf.len; 2281 2282 /* Check that the softirq receive buffer is valid */ 2283 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 2284 sizeof(req->rq_rcv_buf)) != 0); 2285 2286 if (req->rq_rcv_buf.len < 12) { 2287 if (!RPC_IS_SOFT(task)) { 2288 task->tk_action = call_bind; 2289 goto out_retry; 2290 } 2291 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n", 2292 clnt->cl_program->name, task->tk_status); 2293 task->tk_action = call_timeout; 2294 goto out_retry; 2295 } 2296 2297 p = rpc_verify_header(task); 2298 if (IS_ERR(p)) { 2299 if (p == ERR_PTR(-EAGAIN)) 2300 goto out_retry; 2301 return; 2302 } 2303 2304 task->tk_action = rpc_exit_task; 2305 2306 if (decode) { 2307 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 2308 task->tk_msg.rpc_resp); 2309 } 2310 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid, 2311 task->tk_status); 2312 return; 2313 out_retry: 2314 task->tk_status = 0; 2315 /* Note: rpc_verify_header() may have freed the RPC slot */ 2316 if (task->tk_rqstp == req) { 2317 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0; 2318 if (task->tk_client->cl_discrtry) 2319 xprt_conditional_disconnect(req->rq_xprt, 2320 req->rq_connect_cookie); 2321 } 2322 } 2323 2324 static __be32 * 2325 rpc_encode_header(struct rpc_task *task) 2326 { 2327 struct rpc_clnt *clnt = task->tk_client; 2328 struct rpc_rqst *req = task->tk_rqstp; 2329 __be32 *p = req->rq_svec[0].iov_base; 2330 2331 /* FIXME: check buffer size? */ 2332 2333 p = xprt_skip_transport_header(req->rq_xprt, p); 2334 *p++ = req->rq_xid; /* XID */ 2335 *p++ = htonl(RPC_CALL); /* CALL */ 2336 *p++ = htonl(RPC_VERSION); /* RPC version */ 2337 *p++ = htonl(clnt->cl_prog); /* program number */ 2338 *p++ = htonl(clnt->cl_vers); /* program version */ 2339 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 2340 p = rpcauth_marshcred(task, p); 2341 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 2342 return p; 2343 } 2344 2345 static __be32 * 2346 rpc_verify_header(struct rpc_task *task) 2347 { 2348 struct rpc_clnt *clnt = task->tk_client; 2349 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 2350 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 2351 __be32 *p = iov->iov_base; 2352 u32 n; 2353 int error = -EACCES; 2354 2355 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) { 2356 /* RFC-1014 says that the representation of XDR data must be a 2357 * multiple of four bytes 2358 * - if it isn't pointer subtraction in the NFS client may give 2359 * undefined results 2360 */ 2361 dprintk("RPC: %5u %s: XDR representation not a multiple of" 2362 " 4 bytes: 0x%x\n", task->tk_pid, __func__, 2363 task->tk_rqstp->rq_rcv_buf.len); 2364 error = -EIO; 2365 goto out_err; 2366 } 2367 if ((len -= 3) < 0) 2368 goto out_overflow; 2369 2370 p += 1; /* skip XID */ 2371 if ((n = ntohl(*p++)) != RPC_REPLY) { 2372 dprintk("RPC: %5u %s: not an RPC reply: %x\n", 2373 task->tk_pid, __func__, n); 2374 error = -EIO; 2375 goto out_garbage; 2376 } 2377 2378 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 2379 if (--len < 0) 2380 goto out_overflow; 2381 switch ((n = ntohl(*p++))) { 2382 case RPC_AUTH_ERROR: 2383 break; 2384 case RPC_MISMATCH: 2385 dprintk("RPC: %5u %s: RPC call version mismatch!\n", 2386 task->tk_pid, __func__); 2387 error = -EPROTONOSUPPORT; 2388 goto out_err; 2389 default: 2390 dprintk("RPC: %5u %s: RPC call rejected, " 2391 "unknown error: %x\n", 2392 task->tk_pid, __func__, n); 2393 error = -EIO; 2394 goto out_err; 2395 } 2396 if (--len < 0) 2397 goto out_overflow; 2398 switch ((n = ntohl(*p++))) { 2399 case RPC_AUTH_REJECTEDCRED: 2400 case RPC_AUTH_REJECTEDVERF: 2401 case RPCSEC_GSS_CREDPROBLEM: 2402 case RPCSEC_GSS_CTXPROBLEM: 2403 if (!task->tk_cred_retry) 2404 break; 2405 task->tk_cred_retry--; 2406 dprintk("RPC: %5u %s: retry stale creds\n", 2407 task->tk_pid, __func__); 2408 rpcauth_invalcred(task); 2409 /* Ensure we obtain a new XID! */ 2410 xprt_release(task); 2411 task->tk_action = call_reserve; 2412 goto out_retry; 2413 case RPC_AUTH_BADCRED: 2414 case RPC_AUTH_BADVERF: 2415 /* possibly garbled cred/verf? */ 2416 if (!task->tk_garb_retry) 2417 break; 2418 task->tk_garb_retry--; 2419 dprintk("RPC: %5u %s: retry garbled creds\n", 2420 task->tk_pid, __func__); 2421 task->tk_action = call_bind; 2422 goto out_retry; 2423 case RPC_AUTH_TOOWEAK: 2424 printk(KERN_NOTICE "RPC: server %s requires stronger " 2425 "authentication.\n", 2426 task->tk_xprt->servername); 2427 break; 2428 default: 2429 dprintk("RPC: %5u %s: unknown auth error: %x\n", 2430 task->tk_pid, __func__, n); 2431 error = -EIO; 2432 } 2433 dprintk("RPC: %5u %s: call rejected %d\n", 2434 task->tk_pid, __func__, n); 2435 goto out_err; 2436 } 2437 p = rpcauth_checkverf(task, p); 2438 if (IS_ERR(p)) { 2439 error = PTR_ERR(p); 2440 dprintk("RPC: %5u %s: auth check failed with %d\n", 2441 task->tk_pid, __func__, error); 2442 goto out_garbage; /* bad verifier, retry */ 2443 } 2444 len = p - (__be32 *)iov->iov_base - 1; 2445 if (len < 0) 2446 goto out_overflow; 2447 switch ((n = ntohl(*p++))) { 2448 case RPC_SUCCESS: 2449 return p; 2450 case RPC_PROG_UNAVAIL: 2451 dprintk("RPC: %5u %s: program %u is unsupported " 2452 "by server %s\n", task->tk_pid, __func__, 2453 (unsigned int)clnt->cl_prog, 2454 task->tk_xprt->servername); 2455 error = -EPFNOSUPPORT; 2456 goto out_err; 2457 case RPC_PROG_MISMATCH: 2458 dprintk("RPC: %5u %s: program %u, version %u unsupported " 2459 "by server %s\n", task->tk_pid, __func__, 2460 (unsigned int)clnt->cl_prog, 2461 (unsigned int)clnt->cl_vers, 2462 task->tk_xprt->servername); 2463 error = -EPROTONOSUPPORT; 2464 goto out_err; 2465 case RPC_PROC_UNAVAIL: 2466 dprintk("RPC: %5u %s: proc %s unsupported by program %u, " 2467 "version %u on server %s\n", 2468 task->tk_pid, __func__, 2469 rpc_proc_name(task), 2470 clnt->cl_prog, clnt->cl_vers, 2471 task->tk_xprt->servername); 2472 error = -EOPNOTSUPP; 2473 goto out_err; 2474 case RPC_GARBAGE_ARGS: 2475 dprintk("RPC: %5u %s: server saw garbage\n", 2476 task->tk_pid, __func__); 2477 break; /* retry */ 2478 default: 2479 dprintk("RPC: %5u %s: server accept status: %x\n", 2480 task->tk_pid, __func__, n); 2481 /* Also retry */ 2482 } 2483 2484 out_garbage: 2485 clnt->cl_stats->rpcgarbage++; 2486 if (task->tk_garb_retry) { 2487 task->tk_garb_retry--; 2488 dprintk("RPC: %5u %s: retrying\n", 2489 task->tk_pid, __func__); 2490 task->tk_action = call_bind; 2491 out_retry: 2492 return ERR_PTR(-EAGAIN); 2493 } 2494 out_err: 2495 rpc_exit(task, error); 2496 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid, 2497 __func__, error); 2498 return ERR_PTR(error); 2499 out_overflow: 2500 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid, 2501 __func__); 2502 goto out_garbage; 2503 } 2504 2505 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2506 { 2507 } 2508 2509 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj) 2510 { 2511 return 0; 2512 } 2513 2514 static struct rpc_procinfo rpcproc_null = { 2515 .p_encode = rpcproc_encode_null, 2516 .p_decode = rpcproc_decode_null, 2517 }; 2518 2519 static int rpc_ping(struct rpc_clnt *clnt) 2520 { 2521 struct rpc_message msg = { 2522 .rpc_proc = &rpcproc_null, 2523 }; 2524 int err; 2525 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2526 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN); 2527 put_rpccred(msg.rpc_cred); 2528 return err; 2529 } 2530 2531 static 2532 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, 2533 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags, 2534 const struct rpc_call_ops *ops, void *data) 2535 { 2536 struct rpc_message msg = { 2537 .rpc_proc = &rpcproc_null, 2538 .rpc_cred = cred, 2539 }; 2540 struct rpc_task_setup task_setup_data = { 2541 .rpc_client = clnt, 2542 .rpc_xprt = xprt, 2543 .rpc_message = &msg, 2544 .callback_ops = (ops != NULL) ? ops : &rpc_default_ops, 2545 .callback_data = data, 2546 .flags = flags, 2547 }; 2548 2549 return rpc_run_task(&task_setup_data); 2550 } 2551 2552 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags) 2553 { 2554 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL); 2555 } 2556 EXPORT_SYMBOL_GPL(rpc_call_null); 2557 2558 struct rpc_cb_add_xprt_calldata { 2559 struct rpc_xprt_switch *xps; 2560 struct rpc_xprt *xprt; 2561 }; 2562 2563 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata) 2564 { 2565 struct rpc_cb_add_xprt_calldata *data = calldata; 2566 2567 if (task->tk_status == 0) 2568 rpc_xprt_switch_add_xprt(data->xps, data->xprt); 2569 } 2570 2571 static void rpc_cb_add_xprt_release(void *calldata) 2572 { 2573 struct rpc_cb_add_xprt_calldata *data = calldata; 2574 2575 xprt_put(data->xprt); 2576 xprt_switch_put(data->xps); 2577 kfree(data); 2578 } 2579 2580 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = { 2581 .rpc_call_done = rpc_cb_add_xprt_done, 2582 .rpc_release = rpc_cb_add_xprt_release, 2583 }; 2584 2585 /** 2586 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt 2587 * @clnt: pointer to struct rpc_clnt 2588 * @xps: pointer to struct rpc_xprt_switch, 2589 * @xprt: pointer struct rpc_xprt 2590 * @dummy: unused 2591 */ 2592 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt, 2593 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt, 2594 void *dummy) 2595 { 2596 struct rpc_cb_add_xprt_calldata *data; 2597 struct rpc_cred *cred; 2598 struct rpc_task *task; 2599 2600 data = kmalloc(sizeof(*data), GFP_NOFS); 2601 if (!data) 2602 return -ENOMEM; 2603 data->xps = xprt_switch_get(xps); 2604 data->xprt = xprt_get(xprt); 2605 2606 cred = authnull_ops.lookup_cred(NULL, NULL, 0); 2607 task = rpc_call_null_helper(clnt, xprt, cred, 2608 RPC_TASK_SOFT|RPC_TASK_SOFTCONN|RPC_TASK_ASYNC, 2609 &rpc_cb_add_xprt_call_ops, data); 2610 put_rpccred(cred); 2611 if (IS_ERR(task)) 2612 return PTR_ERR(task); 2613 rpc_put_task(task); 2614 return 1; 2615 } 2616 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt); 2617 2618 /** 2619 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt 2620 * @clnt: pointer to struct rpc_clnt 2621 * @xprtargs: pointer to struct xprt_create 2622 * @setup: callback to test and/or set up the connection 2623 * @data: pointer to setup function data 2624 * 2625 * Creates a new transport using the parameters set in args and 2626 * adds it to clnt. 2627 * If ping is set, then test that connectivity succeeds before 2628 * adding the new transport. 2629 * 2630 */ 2631 int rpc_clnt_add_xprt(struct rpc_clnt *clnt, 2632 struct xprt_create *xprtargs, 2633 int (*setup)(struct rpc_clnt *, 2634 struct rpc_xprt_switch *, 2635 struct rpc_xprt *, 2636 void *), 2637 void *data) 2638 { 2639 struct rpc_xprt_switch *xps; 2640 struct rpc_xprt *xprt; 2641 unsigned long reconnect_timeout; 2642 unsigned char resvport; 2643 int ret = 0; 2644 2645 rcu_read_lock(); 2646 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch)); 2647 xprt = xprt_iter_xprt(&clnt->cl_xpi); 2648 if (xps == NULL || xprt == NULL) { 2649 rcu_read_unlock(); 2650 return -EAGAIN; 2651 } 2652 resvport = xprt->resvport; 2653 reconnect_timeout = xprt->max_reconnect_timeout; 2654 rcu_read_unlock(); 2655 2656 xprt = xprt_create_transport(xprtargs); 2657 if (IS_ERR(xprt)) { 2658 ret = PTR_ERR(xprt); 2659 goto out_put_switch; 2660 } 2661 xprt->resvport = resvport; 2662 xprt->max_reconnect_timeout = reconnect_timeout; 2663 2664 rpc_xprt_switch_set_roundrobin(xps); 2665 if (setup) { 2666 ret = setup(clnt, xps, xprt, data); 2667 if (ret != 0) 2668 goto out_put_xprt; 2669 } 2670 rpc_xprt_switch_add_xprt(xps, xprt); 2671 out_put_xprt: 2672 xprt_put(xprt); 2673 out_put_switch: 2674 xprt_switch_put(xps); 2675 return ret; 2676 } 2677 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt); 2678 2679 static int 2680 rpc_xprt_cap_max_reconnect_timeout(struct rpc_clnt *clnt, 2681 struct rpc_xprt *xprt, 2682 void *data) 2683 { 2684 unsigned long timeout = *((unsigned long *)data); 2685 2686 if (timeout < xprt->max_reconnect_timeout) 2687 xprt->max_reconnect_timeout = timeout; 2688 return 0; 2689 } 2690 2691 void 2692 rpc_cap_max_reconnect_timeout(struct rpc_clnt *clnt, unsigned long timeo) 2693 { 2694 rpc_clnt_iterate_for_each_xprt(clnt, 2695 rpc_xprt_cap_max_reconnect_timeout, 2696 &timeo); 2697 } 2698 EXPORT_SYMBOL_GPL(rpc_cap_max_reconnect_timeout); 2699 2700 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 2701 static void rpc_show_header(void) 2702 { 2703 printk(KERN_INFO "-pid- flgs status -client- --rqstp- " 2704 "-timeout ---ops--\n"); 2705 } 2706 2707 static void rpc_show_task(const struct rpc_clnt *clnt, 2708 const struct rpc_task *task) 2709 { 2710 const char *rpc_waitq = "none"; 2711 2712 if (RPC_IS_QUEUED(task)) 2713 rpc_waitq = rpc_qname(task->tk_waitqueue); 2714 2715 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n", 2716 task->tk_pid, task->tk_flags, task->tk_status, 2717 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops, 2718 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task), 2719 task->tk_action, rpc_waitq); 2720 } 2721 2722 void rpc_show_tasks(struct net *net) 2723 { 2724 struct rpc_clnt *clnt; 2725 struct rpc_task *task; 2726 int header = 0; 2727 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 2728 2729 spin_lock(&sn->rpc_client_lock); 2730 list_for_each_entry(clnt, &sn->all_clients, cl_clients) { 2731 spin_lock(&clnt->cl_lock); 2732 list_for_each_entry(task, &clnt->cl_tasks, tk_task) { 2733 if (!header) { 2734 rpc_show_header(); 2735 header++; 2736 } 2737 rpc_show_task(clnt, task); 2738 } 2739 spin_unlock(&clnt->cl_lock); 2740 } 2741 spin_unlock(&sn->rpc_client_lock); 2742 } 2743 #endif 2744 2745 #if IS_ENABLED(CONFIG_SUNRPC_SWAP) 2746 static int 2747 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt, 2748 struct rpc_xprt *xprt, 2749 void *dummy) 2750 { 2751 return xprt_enable_swap(xprt); 2752 } 2753 2754 int 2755 rpc_clnt_swap_activate(struct rpc_clnt *clnt) 2756 { 2757 if (atomic_inc_return(&clnt->cl_swapper) == 1) 2758 return rpc_clnt_iterate_for_each_xprt(clnt, 2759 rpc_clnt_swap_activate_callback, NULL); 2760 return 0; 2761 } 2762 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate); 2763 2764 static int 2765 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt, 2766 struct rpc_xprt *xprt, 2767 void *dummy) 2768 { 2769 xprt_disable_swap(xprt); 2770 return 0; 2771 } 2772 2773 void 2774 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt) 2775 { 2776 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) 2777 rpc_clnt_iterate_for_each_xprt(clnt, 2778 rpc_clnt_swap_deactivate_callback, NULL); 2779 } 2780 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate); 2781 #endif /* CONFIG_SUNRPC_SWAP */ 2782