clnt.c revision a246b0105bbd9a70a698f69baae2042996f2a0e9
1/* 2 * linux/net/sunrpc/rpcclnt.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 * NB: BSD uses a more intelligent approach to guessing when a request 17 * or reply has been lost by keeping the RTO estimate for each procedure. 18 * We currently make do with a constant timeout value. 19 * 20 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com> 21 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de> 22 */ 23 24#include <asm/system.h> 25 26#include <linux/module.h> 27#include <linux/types.h> 28#include <linux/mm.h> 29#include <linux/slab.h> 30#include <linux/in.h> 31#include <linux/utsname.h> 32 33#include <linux/sunrpc/clnt.h> 34#include <linux/workqueue.h> 35#include <linux/sunrpc/rpc_pipe_fs.h> 36 37#include <linux/nfs.h> 38 39 40#define RPC_SLACK_SPACE (1024) /* total overkill */ 41 42#ifdef RPC_DEBUG 43# define RPCDBG_FACILITY RPCDBG_CALL 44#endif 45 46static DECLARE_WAIT_QUEUE_HEAD(destroy_wait); 47 48 49static void call_start(struct rpc_task *task); 50static void call_reserve(struct rpc_task *task); 51static void call_reserveresult(struct rpc_task *task); 52static void call_allocate(struct rpc_task *task); 53static void call_encode(struct rpc_task *task); 54static void call_decode(struct rpc_task *task); 55static void call_bind(struct rpc_task *task); 56static void call_bind_status(struct rpc_task *task); 57static void call_transmit(struct rpc_task *task); 58static void call_status(struct rpc_task *task); 59static void call_refresh(struct rpc_task *task); 60static void call_refreshresult(struct rpc_task *task); 61static void call_timeout(struct rpc_task *task); 62static void call_connect(struct rpc_task *task); 63static void call_connect_status(struct rpc_task *task); 64static u32 * call_header(struct rpc_task *task); 65static u32 * call_verify(struct rpc_task *task); 66 67 68static int 69rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name) 70{ 71 static uint32_t clntid; 72 int error; 73 74 if (dir_name == NULL) 75 return 0; 76 for (;;) { 77 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname), 78 "%s/clnt%x", dir_name, 79 (unsigned int)clntid++); 80 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0'; 81 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt); 82 if (!IS_ERR(clnt->cl_dentry)) 83 return 0; 84 error = PTR_ERR(clnt->cl_dentry); 85 if (error != -EEXIST) { 86 printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n", 87 clnt->cl_pathname, error); 88 return error; 89 } 90 } 91} 92 93/* 94 * Create an RPC client 95 * FIXME: This should also take a flags argument (as in task->tk_flags). 96 * It's called (among others) from pmap_create_client, which may in 97 * turn be called by an async task. In this case, rpciod should not be 98 * made to sleep too long. 99 */ 100struct rpc_clnt * 101rpc_new_client(struct rpc_xprt *xprt, char *servname, 102 struct rpc_program *program, u32 vers, 103 rpc_authflavor_t flavor) 104{ 105 struct rpc_version *version; 106 struct rpc_clnt *clnt = NULL; 107 struct rpc_auth *auth; 108 int err; 109 int len; 110 111 dprintk("RPC: creating %s client for %s (xprt %p)\n", 112 program->name, servname, xprt); 113 114 err = -EINVAL; 115 if (!xprt) 116 goto out_err; 117 if (vers >= program->nrvers || !(version = program->version[vers])) 118 goto out_err; 119 120 err = -ENOMEM; 121 clnt = (struct rpc_clnt *) kmalloc(sizeof(*clnt), GFP_KERNEL); 122 if (!clnt) 123 goto out_err; 124 memset(clnt, 0, sizeof(*clnt)); 125 atomic_set(&clnt->cl_users, 0); 126 atomic_set(&clnt->cl_count, 1); 127 clnt->cl_parent = clnt; 128 129 clnt->cl_server = clnt->cl_inline_name; 130 len = strlen(servname) + 1; 131 if (len > sizeof(clnt->cl_inline_name)) { 132 char *buf = kmalloc(len, GFP_KERNEL); 133 if (buf != 0) 134 clnt->cl_server = buf; 135 else 136 len = sizeof(clnt->cl_inline_name); 137 } 138 strlcpy(clnt->cl_server, servname, len); 139 140 clnt->cl_xprt = xprt; 141 clnt->cl_procinfo = version->procs; 142 clnt->cl_maxproc = version->nrprocs; 143 clnt->cl_protname = program->name; 144 clnt->cl_pmap = &clnt->cl_pmap_default; 145 clnt->cl_port = xprt->addr.sin_port; 146 clnt->cl_prog = program->number; 147 clnt->cl_vers = version->number; 148 clnt->cl_prot = xprt->prot; 149 clnt->cl_stats = program->stats; 150 rpc_init_wait_queue(&clnt->cl_pmap_default.pm_bindwait, "bindwait"); 151 152 if (!clnt->cl_port) 153 clnt->cl_autobind = 1; 154 155 clnt->cl_rtt = &clnt->cl_rtt_default; 156 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval); 157 158 err = rpc_setup_pipedir(clnt, program->pipe_dir_name); 159 if (err < 0) 160 goto out_no_path; 161 162 auth = rpcauth_create(flavor, clnt); 163 if (IS_ERR(auth)) { 164 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n", 165 flavor); 166 err = PTR_ERR(auth); 167 goto out_no_auth; 168 } 169 170 /* save the nodename */ 171 clnt->cl_nodelen = strlen(system_utsname.nodename); 172 if (clnt->cl_nodelen > UNX_MAXNODENAME) 173 clnt->cl_nodelen = UNX_MAXNODENAME; 174 memcpy(clnt->cl_nodename, system_utsname.nodename, clnt->cl_nodelen); 175 return clnt; 176 177out_no_auth: 178 rpc_rmdir(clnt->cl_pathname); 179out_no_path: 180 if (clnt->cl_server != clnt->cl_inline_name) 181 kfree(clnt->cl_server); 182 kfree(clnt); 183out_err: 184 xprt_destroy(xprt); 185 return ERR_PTR(err); 186} 187 188/** 189 * Create an RPC client 190 * @xprt - pointer to xprt struct 191 * @servname - name of server 192 * @info - rpc_program 193 * @version - rpc_program version 194 * @authflavor - rpc_auth flavour to use 195 * 196 * Creates an RPC client structure, then pings the server in order to 197 * determine if it is up, and if it supports this program and version. 198 * 199 * This function should never be called by asynchronous tasks such as 200 * the portmapper. 201 */ 202struct rpc_clnt *rpc_create_client(struct rpc_xprt *xprt, char *servname, 203 struct rpc_program *info, u32 version, rpc_authflavor_t authflavor) 204{ 205 struct rpc_clnt *clnt; 206 int err; 207 208 clnt = rpc_new_client(xprt, servname, info, version, authflavor); 209 if (IS_ERR(clnt)) 210 return clnt; 211 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 212 if (err == 0) 213 return clnt; 214 rpc_shutdown_client(clnt); 215 return ERR_PTR(err); 216} 217 218/* 219 * This function clones the RPC client structure. It allows us to share the 220 * same transport while varying parameters such as the authentication 221 * flavour. 222 */ 223struct rpc_clnt * 224rpc_clone_client(struct rpc_clnt *clnt) 225{ 226 struct rpc_clnt *new; 227 228 new = (struct rpc_clnt *)kmalloc(sizeof(*new), GFP_KERNEL); 229 if (!new) 230 goto out_no_clnt; 231 memcpy(new, clnt, sizeof(*new)); 232 atomic_set(&new->cl_count, 1); 233 atomic_set(&new->cl_users, 0); 234 new->cl_parent = clnt; 235 atomic_inc(&clnt->cl_count); 236 /* Duplicate portmapper */ 237 rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait"); 238 /* Turn off autobind on clones */ 239 new->cl_autobind = 0; 240 new->cl_oneshot = 0; 241 new->cl_dead = 0; 242 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval); 243 if (new->cl_auth) 244 atomic_inc(&new->cl_auth->au_count); 245 new->cl_pmap = &new->cl_pmap_default; 246 rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait"); 247 return new; 248out_no_clnt: 249 printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__); 250 return ERR_PTR(-ENOMEM); 251} 252 253/* 254 * Properly shut down an RPC client, terminating all outstanding 255 * requests. Note that we must be certain that cl_oneshot and 256 * cl_dead are cleared, or else the client would be destroyed 257 * when the last task releases it. 258 */ 259int 260rpc_shutdown_client(struct rpc_clnt *clnt) 261{ 262 dprintk("RPC: shutting down %s client for %s, tasks=%d\n", 263 clnt->cl_protname, clnt->cl_server, 264 atomic_read(&clnt->cl_users)); 265 266 while (atomic_read(&clnt->cl_users) > 0) { 267 /* Don't let rpc_release_client destroy us */ 268 clnt->cl_oneshot = 0; 269 clnt->cl_dead = 0; 270 rpc_killall_tasks(clnt); 271 sleep_on_timeout(&destroy_wait, 1*HZ); 272 } 273 274 if (atomic_read(&clnt->cl_users) < 0) { 275 printk(KERN_ERR "RPC: rpc_shutdown_client clnt %p tasks=%d\n", 276 clnt, atomic_read(&clnt->cl_users)); 277#ifdef RPC_DEBUG 278 rpc_show_tasks(); 279#endif 280 BUG(); 281 } 282 283 return rpc_destroy_client(clnt); 284} 285 286/* 287 * Delete an RPC client 288 */ 289int 290rpc_destroy_client(struct rpc_clnt *clnt) 291{ 292 if (!atomic_dec_and_test(&clnt->cl_count)) 293 return 1; 294 BUG_ON(atomic_read(&clnt->cl_users) != 0); 295 296 dprintk("RPC: destroying %s client for %s\n", 297 clnt->cl_protname, clnt->cl_server); 298 if (clnt->cl_auth) { 299 rpcauth_destroy(clnt->cl_auth); 300 clnt->cl_auth = NULL; 301 } 302 if (clnt->cl_parent != clnt) { 303 rpc_destroy_client(clnt->cl_parent); 304 goto out_free; 305 } 306 if (clnt->cl_pathname[0]) 307 rpc_rmdir(clnt->cl_pathname); 308 if (clnt->cl_xprt) { 309 xprt_destroy(clnt->cl_xprt); 310 clnt->cl_xprt = NULL; 311 } 312 if (clnt->cl_server != clnt->cl_inline_name) 313 kfree(clnt->cl_server); 314out_free: 315 kfree(clnt); 316 return 0; 317} 318 319/* 320 * Release an RPC client 321 */ 322void 323rpc_release_client(struct rpc_clnt *clnt) 324{ 325 dprintk("RPC: rpc_release_client(%p, %d)\n", 326 clnt, atomic_read(&clnt->cl_users)); 327 328 if (!atomic_dec_and_test(&clnt->cl_users)) 329 return; 330 wake_up(&destroy_wait); 331 if (clnt->cl_oneshot || clnt->cl_dead) 332 rpc_destroy_client(clnt); 333} 334 335/** 336 * rpc_bind_new_program - bind a new RPC program to an existing client 337 * @old - old rpc_client 338 * @program - rpc program to set 339 * @vers - rpc program version 340 * 341 * Clones the rpc client and sets up a new RPC program. This is mainly 342 * of use for enabling different RPC programs to share the same transport. 343 * The Sun NFSv2/v3 ACL protocol can do this. 344 */ 345struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, 346 struct rpc_program *program, 347 int vers) 348{ 349 struct rpc_clnt *clnt; 350 struct rpc_version *version; 351 int err; 352 353 BUG_ON(vers >= program->nrvers || !program->version[vers]); 354 version = program->version[vers]; 355 clnt = rpc_clone_client(old); 356 if (IS_ERR(clnt)) 357 goto out; 358 clnt->cl_procinfo = version->procs; 359 clnt->cl_maxproc = version->nrprocs; 360 clnt->cl_protname = program->name; 361 clnt->cl_prog = program->number; 362 clnt->cl_vers = version->number; 363 clnt->cl_stats = program->stats; 364 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); 365 if (err != 0) { 366 rpc_shutdown_client(clnt); 367 clnt = ERR_PTR(err); 368 } 369out: 370 return clnt; 371} 372 373/* 374 * Default callback for async RPC calls 375 */ 376static void 377rpc_default_callback(struct rpc_task *task) 378{ 379} 380 381/* 382 * Export the signal mask handling for synchronous code that 383 * sleeps on RPC calls 384 */ 385#define RPC_INTR_SIGNALS (sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGKILL)) 386 387static void rpc_save_sigmask(sigset_t *oldset, int intr) 388{ 389 unsigned long sigallow = 0; 390 sigset_t sigmask; 391 392 /* Block all signals except those listed in sigallow */ 393 if (intr) 394 sigallow |= RPC_INTR_SIGNALS; 395 siginitsetinv(&sigmask, sigallow); 396 sigprocmask(SIG_BLOCK, &sigmask, oldset); 397} 398 399static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset) 400{ 401 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task)); 402} 403 404static inline void rpc_restore_sigmask(sigset_t *oldset) 405{ 406 sigprocmask(SIG_SETMASK, oldset, NULL); 407} 408 409void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset) 410{ 411 rpc_save_sigmask(oldset, clnt->cl_intr); 412} 413 414void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset) 415{ 416 rpc_restore_sigmask(oldset); 417} 418 419/* 420 * New rpc_call implementation 421 */ 422int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags) 423{ 424 struct rpc_task *task; 425 sigset_t oldset; 426 int status; 427 428 /* If this client is slain all further I/O fails */ 429 if (clnt->cl_dead) 430 return -EIO; 431 432 BUG_ON(flags & RPC_TASK_ASYNC); 433 434 status = -ENOMEM; 435 task = rpc_new_task(clnt, NULL, flags); 436 if (task == NULL) 437 goto out; 438 439 /* Mask signals on RPC calls _and_ GSS_AUTH upcalls */ 440 rpc_task_sigmask(task, &oldset); 441 442 rpc_call_setup(task, msg, 0); 443 444 /* Set up the call info struct and execute the task */ 445 if (task->tk_status == 0) { 446 status = rpc_execute(task); 447 } else { 448 status = task->tk_status; 449 rpc_release_task(task); 450 } 451 452 rpc_restore_sigmask(&oldset); 453out: 454 return status; 455} 456 457/* 458 * New rpc_call implementation 459 */ 460int 461rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags, 462 rpc_action callback, void *data) 463{ 464 struct rpc_task *task; 465 sigset_t oldset; 466 int status; 467 468 /* If this client is slain all further I/O fails */ 469 if (clnt->cl_dead) 470 return -EIO; 471 472 flags |= RPC_TASK_ASYNC; 473 474 /* Create/initialize a new RPC task */ 475 if (!callback) 476 callback = rpc_default_callback; 477 status = -ENOMEM; 478 if (!(task = rpc_new_task(clnt, callback, flags))) 479 goto out; 480 task->tk_calldata = data; 481 482 /* Mask signals on GSS_AUTH upcalls */ 483 rpc_task_sigmask(task, &oldset); 484 485 rpc_call_setup(task, msg, 0); 486 487 /* Set up the call info struct and execute the task */ 488 status = task->tk_status; 489 if (status == 0) 490 rpc_execute(task); 491 else 492 rpc_release_task(task); 493 494 rpc_restore_sigmask(&oldset); 495out: 496 return status; 497} 498 499 500void 501rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags) 502{ 503 task->tk_msg = *msg; 504 task->tk_flags |= flags; 505 /* Bind the user cred */ 506 if (task->tk_msg.rpc_cred != NULL) 507 rpcauth_holdcred(task); 508 else 509 rpcauth_bindcred(task); 510 511 if (task->tk_status == 0) 512 task->tk_action = call_start; 513 else 514 task->tk_action = NULL; 515} 516 517void 518rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize) 519{ 520 struct rpc_xprt *xprt = clnt->cl_xprt; 521 522 xprt->sndsize = 0; 523 if (sndsize) 524 xprt->sndsize = sndsize + RPC_SLACK_SPACE; 525 xprt->rcvsize = 0; 526 if (rcvsize) 527 xprt->rcvsize = rcvsize + RPC_SLACK_SPACE; 528 xprt->ops->set_buffer_size(xprt); 529} 530 531/* 532 * Return size of largest payload RPC client can support, in bytes 533 * 534 * For stream transports, this is one RPC record fragment (see RFC 535 * 1831), as we don't support multi-record requests yet. For datagram 536 * transports, this is the size of an IP packet minus the IP, UDP, and 537 * RPC header sizes. 538 */ 539size_t rpc_max_payload(struct rpc_clnt *clnt) 540{ 541 return clnt->cl_xprt->max_payload; 542} 543EXPORT_SYMBOL(rpc_max_payload); 544 545/* 546 * Restart an (async) RPC call. Usually called from within the 547 * exit handler. 548 */ 549void 550rpc_restart_call(struct rpc_task *task) 551{ 552 if (RPC_ASSASSINATED(task)) 553 return; 554 555 task->tk_action = call_start; 556} 557 558/* 559 * 0. Initial state 560 * 561 * Other FSM states can be visited zero or more times, but 562 * this state is visited exactly once for each RPC. 563 */ 564static void 565call_start(struct rpc_task *task) 566{ 567 struct rpc_clnt *clnt = task->tk_client; 568 569 dprintk("RPC: %4d call_start %s%d proc %d (%s)\n", task->tk_pid, 570 clnt->cl_protname, clnt->cl_vers, task->tk_msg.rpc_proc->p_proc, 571 (RPC_IS_ASYNC(task) ? "async" : "sync")); 572 573 /* Increment call count */ 574 task->tk_msg.rpc_proc->p_count++; 575 clnt->cl_stats->rpccnt++; 576 task->tk_action = call_reserve; 577} 578 579/* 580 * 1. Reserve an RPC call slot 581 */ 582static void 583call_reserve(struct rpc_task *task) 584{ 585 dprintk("RPC: %4d call_reserve\n", task->tk_pid); 586 587 if (!rpcauth_uptodatecred(task)) { 588 task->tk_action = call_refresh; 589 return; 590 } 591 592 task->tk_status = 0; 593 task->tk_action = call_reserveresult; 594 xprt_reserve(task); 595} 596 597/* 598 * 1b. Grok the result of xprt_reserve() 599 */ 600static void 601call_reserveresult(struct rpc_task *task) 602{ 603 int status = task->tk_status; 604 605 dprintk("RPC: %4d call_reserveresult (status %d)\n", 606 task->tk_pid, task->tk_status); 607 608 /* 609 * After a call to xprt_reserve(), we must have either 610 * a request slot or else an error status. 611 */ 612 task->tk_status = 0; 613 if (status >= 0) { 614 if (task->tk_rqstp) { 615 task->tk_action = call_allocate; 616 return; 617 } 618 619 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n", 620 __FUNCTION__, status); 621 rpc_exit(task, -EIO); 622 return; 623 } 624 625 /* 626 * Even though there was an error, we may have acquired 627 * a request slot somehow. Make sure not to leak it. 628 */ 629 if (task->tk_rqstp) { 630 printk(KERN_ERR "%s: status=%d, request allocated anyway\n", 631 __FUNCTION__, status); 632 xprt_release(task); 633 } 634 635 switch (status) { 636 case -EAGAIN: /* woken up; retry */ 637 task->tk_action = call_reserve; 638 return; 639 case -EIO: /* probably a shutdown */ 640 break; 641 default: 642 printk(KERN_ERR "%s: unrecognized error %d, exiting\n", 643 __FUNCTION__, status); 644 break; 645 } 646 rpc_exit(task, status); 647} 648 649/* 650 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc. 651 * (Note: buffer memory is freed in rpc_task_release). 652 */ 653static void 654call_allocate(struct rpc_task *task) 655{ 656 unsigned int bufsiz; 657 658 dprintk("RPC: %4d call_allocate (status %d)\n", 659 task->tk_pid, task->tk_status); 660 task->tk_action = call_bind; 661 if (task->tk_buffer) 662 return; 663 664 /* FIXME: compute buffer requirements more exactly using 665 * auth->au_wslack */ 666 bufsiz = task->tk_msg.rpc_proc->p_bufsiz + RPC_SLACK_SPACE; 667 668 if (rpc_malloc(task, bufsiz << 1) != NULL) 669 return; 670 printk(KERN_INFO "RPC: buffer allocation failed for task %p\n", task); 671 672 if (RPC_IS_ASYNC(task) || !signalled()) { 673 xprt_release(task); 674 task->tk_action = call_reserve; 675 rpc_delay(task, HZ>>4); 676 return; 677 } 678 679 rpc_exit(task, -ERESTARTSYS); 680} 681 682/* 683 * 3. Encode arguments of an RPC call 684 */ 685static void 686call_encode(struct rpc_task *task) 687{ 688 struct rpc_clnt *clnt = task->tk_client; 689 struct rpc_rqst *req = task->tk_rqstp; 690 struct xdr_buf *sndbuf = &req->rq_snd_buf; 691 struct xdr_buf *rcvbuf = &req->rq_rcv_buf; 692 unsigned int bufsiz; 693 kxdrproc_t encode; 694 int status; 695 u32 *p; 696 697 dprintk("RPC: %4d call_encode (status %d)\n", 698 task->tk_pid, task->tk_status); 699 700 /* Default buffer setup */ 701 bufsiz = task->tk_bufsize >> 1; 702 sndbuf->head[0].iov_base = (void *)task->tk_buffer; 703 sndbuf->head[0].iov_len = bufsiz; 704 sndbuf->tail[0].iov_len = 0; 705 sndbuf->page_len = 0; 706 sndbuf->len = 0; 707 sndbuf->buflen = bufsiz; 708 rcvbuf->head[0].iov_base = (void *)((char *)task->tk_buffer + bufsiz); 709 rcvbuf->head[0].iov_len = bufsiz; 710 rcvbuf->tail[0].iov_len = 0; 711 rcvbuf->page_len = 0; 712 rcvbuf->len = 0; 713 rcvbuf->buflen = bufsiz; 714 715 /* Encode header and provided arguments */ 716 encode = task->tk_msg.rpc_proc->p_encode; 717 if (!(p = call_header(task))) { 718 printk(KERN_INFO "RPC: call_header failed, exit EIO\n"); 719 rpc_exit(task, -EIO); 720 return; 721 } 722 if (encode && (status = rpcauth_wrap_req(task, encode, req, p, 723 task->tk_msg.rpc_argp)) < 0) { 724 printk(KERN_WARNING "%s: can't encode arguments: %d\n", 725 clnt->cl_protname, -status); 726 rpc_exit(task, status); 727 } 728} 729 730/* 731 * 4. Get the server port number if not yet set 732 */ 733static void 734call_bind(struct rpc_task *task) 735{ 736 struct rpc_clnt *clnt = task->tk_client; 737 738 dprintk("RPC: %4d call_bind (status %d)\n", 739 task->tk_pid, task->tk_status); 740 741 task->tk_action = call_connect; 742 if (!clnt->cl_port) { 743 task->tk_action = call_bind_status; 744 task->tk_timeout = RPC_CONNECT_TIMEOUT; 745 rpc_getport(task, clnt); 746 } 747} 748 749/* 750 * 4a. Sort out bind result 751 */ 752static void 753call_bind_status(struct rpc_task *task) 754{ 755 int status = -EACCES; 756 757 if (task->tk_status >= 0) { 758 dprintk("RPC: %4d call_bind_status (status %d)\n", 759 task->tk_pid, task->tk_status); 760 task->tk_status = 0; 761 task->tk_action = call_connect; 762 return; 763 } 764 765 switch (task->tk_status) { 766 case -EACCES: 767 dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n", 768 task->tk_pid); 769 break; 770 case -ETIMEDOUT: 771 dprintk("RPC: %4d rpcbind request timed out\n", 772 task->tk_pid); 773 if (RPC_IS_SOFT(task)) { 774 status = -EIO; 775 break; 776 } 777 goto retry_bind; 778 case -EPFNOSUPPORT: 779 dprintk("RPC: %4d remote rpcbind service unavailable\n", 780 task->tk_pid); 781 break; 782 case -EPROTONOSUPPORT: 783 dprintk("RPC: %4d remote rpcbind version 2 unavailable\n", 784 task->tk_pid); 785 break; 786 default: 787 dprintk("RPC: %4d unrecognized rpcbind error (%d)\n", 788 task->tk_pid, -task->tk_status); 789 status = -EIO; 790 break; 791 } 792 793 rpc_exit(task, status); 794 return; 795 796retry_bind: 797 task->tk_status = 0; 798 task->tk_action = call_bind; 799 return; 800} 801 802/* 803 * 4b. Connect to the RPC server 804 */ 805static void 806call_connect(struct rpc_task *task) 807{ 808 struct rpc_xprt *xprt = task->tk_xprt; 809 810 dprintk("RPC: %4d call_connect xprt %p %s connected\n", 811 task->tk_pid, xprt, 812 (xprt_connected(xprt) ? "is" : "is not")); 813 814 task->tk_action = call_transmit; 815 if (!xprt_connected(xprt)) { 816 task->tk_action = call_connect_status; 817 if (task->tk_status < 0) 818 return; 819 xprt_connect(task); 820 } 821} 822 823/* 824 * 4c. Sort out connect result 825 */ 826static void 827call_connect_status(struct rpc_task *task) 828{ 829 struct rpc_clnt *clnt = task->tk_client; 830 int status = task->tk_status; 831 832 dprintk("RPC: %5u call_connect_status (status %d)\n", 833 task->tk_pid, task->tk_status); 834 835 task->tk_status = 0; 836 if (status >= 0) { 837 clnt->cl_stats->netreconn++; 838 task->tk_action = call_transmit; 839 return; 840 } 841 842 /* Something failed: remote service port may have changed */ 843 if (clnt->cl_autobind) 844 clnt->cl_port = 0; 845 846 switch (status) { 847 case -ENOTCONN: 848 case -ETIMEDOUT: 849 case -EAGAIN: 850 task->tk_action = call_bind; 851 break; 852 default: 853 rpc_exit(task, -EIO); 854 break; 855 } 856} 857 858/* 859 * 5. Transmit the RPC request, and wait for reply 860 */ 861static void 862call_transmit(struct rpc_task *task) 863{ 864 dprintk("RPC: %4d call_transmit (status %d)\n", 865 task->tk_pid, task->tk_status); 866 867 task->tk_action = call_status; 868 if (task->tk_status < 0) 869 return; 870 task->tk_status = xprt_prepare_transmit(task); 871 if (task->tk_status != 0) 872 return; 873 /* Encode here so that rpcsec_gss can use correct sequence number. */ 874 if (!task->tk_rqstp->rq_bytes_sent) 875 call_encode(task); 876 if (task->tk_status < 0) 877 return; 878 xprt_transmit(task); 879 if (task->tk_status < 0) 880 return; 881 if (!task->tk_msg.rpc_proc->p_decode) { 882 task->tk_action = NULL; 883 rpc_wake_up_task(task); 884 } 885} 886 887/* 888 * 6. Sort out the RPC call status 889 */ 890static void 891call_status(struct rpc_task *task) 892{ 893 struct rpc_clnt *clnt = task->tk_client; 894 struct rpc_rqst *req = task->tk_rqstp; 895 int status; 896 897 if (req->rq_received > 0 && !req->rq_bytes_sent) 898 task->tk_status = req->rq_received; 899 900 dprintk("RPC: %4d call_status (status %d)\n", 901 task->tk_pid, task->tk_status); 902 903 status = task->tk_status; 904 if (status >= 0) { 905 task->tk_action = call_decode; 906 return; 907 } 908 909 task->tk_status = 0; 910 switch(status) { 911 case -ETIMEDOUT: 912 task->tk_action = call_timeout; 913 break; 914 case -ECONNREFUSED: 915 case -ENOTCONN: 916 req->rq_bytes_sent = 0; 917 if (clnt->cl_autobind) 918 clnt->cl_port = 0; 919 task->tk_action = call_bind; 920 break; 921 case -EAGAIN: 922 task->tk_action = call_transmit; 923 break; 924 case -EIO: 925 /* shutdown or soft timeout */ 926 rpc_exit(task, status); 927 break; 928 default: 929 if (clnt->cl_chatty) 930 printk("%s: RPC call returned error %d\n", 931 clnt->cl_protname, -status); 932 rpc_exit(task, status); 933 break; 934 } 935} 936 937/* 938 * 6a. Handle RPC timeout 939 * We do not release the request slot, so we keep using the 940 * same XID for all retransmits. 941 */ 942static void 943call_timeout(struct rpc_task *task) 944{ 945 struct rpc_clnt *clnt = task->tk_client; 946 947 if (xprt_adjust_timeout(task->tk_rqstp) == 0) { 948 dprintk("RPC: %4d call_timeout (minor)\n", task->tk_pid); 949 goto retry; 950 } 951 952 dprintk("RPC: %4d call_timeout (major)\n", task->tk_pid); 953 if (RPC_IS_SOFT(task)) { 954 if (clnt->cl_chatty) 955 printk(KERN_NOTICE "%s: server %s not responding, timed out\n", 956 clnt->cl_protname, clnt->cl_server); 957 rpc_exit(task, -EIO); 958 return; 959 } 960 961 if (clnt->cl_chatty && !(task->tk_flags & RPC_CALL_MAJORSEEN)) { 962 task->tk_flags |= RPC_CALL_MAJORSEEN; 963 printk(KERN_NOTICE "%s: server %s not responding, still trying\n", 964 clnt->cl_protname, clnt->cl_server); 965 } 966 if (clnt->cl_autobind) 967 clnt->cl_port = 0; 968 969retry: 970 clnt->cl_stats->rpcretrans++; 971 task->tk_action = call_bind; 972 task->tk_status = 0; 973} 974 975/* 976 * 7. Decode the RPC reply 977 */ 978static void 979call_decode(struct rpc_task *task) 980{ 981 struct rpc_clnt *clnt = task->tk_client; 982 struct rpc_rqst *req = task->tk_rqstp; 983 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode; 984 u32 *p; 985 986 dprintk("RPC: %4d call_decode (status %d)\n", 987 task->tk_pid, task->tk_status); 988 989 if (clnt->cl_chatty && (task->tk_flags & RPC_CALL_MAJORSEEN)) { 990 printk(KERN_NOTICE "%s: server %s OK\n", 991 clnt->cl_protname, clnt->cl_server); 992 task->tk_flags &= ~RPC_CALL_MAJORSEEN; 993 } 994 995 if (task->tk_status < 12) { 996 if (!RPC_IS_SOFT(task)) { 997 task->tk_action = call_bind; 998 clnt->cl_stats->rpcretrans++; 999 goto out_retry; 1000 } 1001 printk(KERN_WARNING "%s: too small RPC reply size (%d bytes)\n", 1002 clnt->cl_protname, task->tk_status); 1003 rpc_exit(task, -EIO); 1004 return; 1005 } 1006 1007 req->rq_rcv_buf.len = req->rq_private_buf.len; 1008 1009 /* Check that the softirq receive buffer is valid */ 1010 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf, 1011 sizeof(req->rq_rcv_buf)) != 0); 1012 1013 /* Verify the RPC header */ 1014 if (!(p = call_verify(task))) { 1015 if (task->tk_action == NULL) 1016 return; 1017 goto out_retry; 1018 } 1019 1020 task->tk_action = NULL; 1021 1022 if (decode) 1023 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p, 1024 task->tk_msg.rpc_resp); 1025 dprintk("RPC: %4d call_decode result %d\n", task->tk_pid, 1026 task->tk_status); 1027 return; 1028out_retry: 1029 req->rq_received = req->rq_private_buf.len = 0; 1030 task->tk_status = 0; 1031} 1032 1033/* 1034 * 8. Refresh the credentials if rejected by the server 1035 */ 1036static void 1037call_refresh(struct rpc_task *task) 1038{ 1039 dprintk("RPC: %4d call_refresh\n", task->tk_pid); 1040 1041 xprt_release(task); /* Must do to obtain new XID */ 1042 task->tk_action = call_refreshresult; 1043 task->tk_status = 0; 1044 task->tk_client->cl_stats->rpcauthrefresh++; 1045 rpcauth_refreshcred(task); 1046} 1047 1048/* 1049 * 8a. Process the results of a credential refresh 1050 */ 1051static void 1052call_refreshresult(struct rpc_task *task) 1053{ 1054 int status = task->tk_status; 1055 dprintk("RPC: %4d call_refreshresult (status %d)\n", 1056 task->tk_pid, task->tk_status); 1057 1058 task->tk_status = 0; 1059 task->tk_action = call_reserve; 1060 if (status >= 0 && rpcauth_uptodatecred(task)) 1061 return; 1062 if (status == -EACCES) { 1063 rpc_exit(task, -EACCES); 1064 return; 1065 } 1066 task->tk_action = call_refresh; 1067 if (status != -ETIMEDOUT) 1068 rpc_delay(task, 3*HZ); 1069 return; 1070} 1071 1072/* 1073 * Call header serialization 1074 */ 1075static u32 * 1076call_header(struct rpc_task *task) 1077{ 1078 struct rpc_clnt *clnt = task->tk_client; 1079 struct rpc_xprt *xprt = clnt->cl_xprt; 1080 struct rpc_rqst *req = task->tk_rqstp; 1081 u32 *p = req->rq_svec[0].iov_base; 1082 1083 /* FIXME: check buffer size? */ 1084 if (xprt->stream) 1085 *p++ = 0; /* fill in later */ 1086 *p++ = req->rq_xid; /* XID */ 1087 *p++ = htonl(RPC_CALL); /* CALL */ 1088 *p++ = htonl(RPC_VERSION); /* RPC version */ 1089 *p++ = htonl(clnt->cl_prog); /* program number */ 1090 *p++ = htonl(clnt->cl_vers); /* program version */ 1091 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */ 1092 p = rpcauth_marshcred(task, p); 1093 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p); 1094 return p; 1095} 1096 1097/* 1098 * Reply header verification 1099 */ 1100static u32 * 1101call_verify(struct rpc_task *task) 1102{ 1103 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0]; 1104 int len = task->tk_rqstp->rq_rcv_buf.len >> 2; 1105 u32 *p = iov->iov_base, n; 1106 int error = -EACCES; 1107 1108 if ((len -= 3) < 0) 1109 goto out_overflow; 1110 p += 1; /* skip XID */ 1111 1112 if ((n = ntohl(*p++)) != RPC_REPLY) { 1113 printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n); 1114 goto out_retry; 1115 } 1116 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) { 1117 if (--len < 0) 1118 goto out_overflow; 1119 switch ((n = ntohl(*p++))) { 1120 case RPC_AUTH_ERROR: 1121 break; 1122 case RPC_MISMATCH: 1123 dprintk("%s: RPC call version mismatch!\n", __FUNCTION__); 1124 error = -EPROTONOSUPPORT; 1125 goto out_err; 1126 default: 1127 dprintk("%s: RPC call rejected, unknown error: %x\n", __FUNCTION__, n); 1128 goto out_eio; 1129 } 1130 if (--len < 0) 1131 goto out_overflow; 1132 switch ((n = ntohl(*p++))) { 1133 case RPC_AUTH_REJECTEDCRED: 1134 case RPC_AUTH_REJECTEDVERF: 1135 case RPCSEC_GSS_CREDPROBLEM: 1136 case RPCSEC_GSS_CTXPROBLEM: 1137 if (!task->tk_cred_retry) 1138 break; 1139 task->tk_cred_retry--; 1140 dprintk("RPC: %4d call_verify: retry stale creds\n", 1141 task->tk_pid); 1142 rpcauth_invalcred(task); 1143 task->tk_action = call_refresh; 1144 return NULL; 1145 case RPC_AUTH_BADCRED: 1146 case RPC_AUTH_BADVERF: 1147 /* possibly garbled cred/verf? */ 1148 if (!task->tk_garb_retry) 1149 break; 1150 task->tk_garb_retry--; 1151 dprintk("RPC: %4d call_verify: retry garbled creds\n", 1152 task->tk_pid); 1153 task->tk_action = call_bind; 1154 return NULL; 1155 case RPC_AUTH_TOOWEAK: 1156 printk(KERN_NOTICE "call_verify: server requires stronger " 1157 "authentication.\n"); 1158 break; 1159 default: 1160 printk(KERN_WARNING "call_verify: unknown auth error: %x\n", n); 1161 error = -EIO; 1162 } 1163 dprintk("RPC: %4d call_verify: call rejected %d\n", 1164 task->tk_pid, n); 1165 goto out_err; 1166 } 1167 if (!(p = rpcauth_checkverf(task, p))) { 1168 printk(KERN_WARNING "call_verify: auth check failed\n"); 1169 goto out_retry; /* bad verifier, retry */ 1170 } 1171 len = p - (u32 *)iov->iov_base - 1; 1172 if (len < 0) 1173 goto out_overflow; 1174 switch ((n = ntohl(*p++))) { 1175 case RPC_SUCCESS: 1176 return p; 1177 case RPC_PROG_UNAVAIL: 1178 dprintk("RPC: call_verify: program %u is unsupported by server %s\n", 1179 (unsigned int)task->tk_client->cl_prog, 1180 task->tk_client->cl_server); 1181 error = -EPFNOSUPPORT; 1182 goto out_err; 1183 case RPC_PROG_MISMATCH: 1184 dprintk("RPC: call_verify: program %u, version %u unsupported by server %s\n", 1185 (unsigned int)task->tk_client->cl_prog, 1186 (unsigned int)task->tk_client->cl_vers, 1187 task->tk_client->cl_server); 1188 error = -EPROTONOSUPPORT; 1189 goto out_err; 1190 case RPC_PROC_UNAVAIL: 1191 dprintk("RPC: call_verify: proc %p unsupported by program %u, version %u on server %s\n", 1192 task->tk_msg.rpc_proc, 1193 task->tk_client->cl_prog, 1194 task->tk_client->cl_vers, 1195 task->tk_client->cl_server); 1196 error = -EOPNOTSUPP; 1197 goto out_err; 1198 case RPC_GARBAGE_ARGS: 1199 dprintk("RPC: %4d %s: server saw garbage\n", task->tk_pid, __FUNCTION__); 1200 break; /* retry */ 1201 default: 1202 printk(KERN_WARNING "call_verify: server accept status: %x\n", n); 1203 /* Also retry */ 1204 } 1205 1206out_retry: 1207 task->tk_client->cl_stats->rpcgarbage++; 1208 if (task->tk_garb_retry) { 1209 task->tk_garb_retry--; 1210 dprintk("RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid); 1211 task->tk_action = call_bind; 1212 return NULL; 1213 } 1214 printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__); 1215out_eio: 1216 error = -EIO; 1217out_err: 1218 rpc_exit(task, error); 1219 return NULL; 1220out_overflow: 1221 printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__); 1222 goto out_retry; 1223} 1224 1225static int rpcproc_encode_null(void *rqstp, u32 *data, void *obj) 1226{ 1227 return 0; 1228} 1229 1230static int rpcproc_decode_null(void *rqstp, u32 *data, void *obj) 1231{ 1232 return 0; 1233} 1234 1235static struct rpc_procinfo rpcproc_null = { 1236 .p_encode = rpcproc_encode_null, 1237 .p_decode = rpcproc_decode_null, 1238}; 1239 1240int rpc_ping(struct rpc_clnt *clnt, int flags) 1241{ 1242 struct rpc_message msg = { 1243 .rpc_proc = &rpcproc_null, 1244 }; 1245 int err; 1246 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0); 1247 err = rpc_call_sync(clnt, &msg, flags); 1248 put_rpccred(msg.rpc_cred); 1249 return err; 1250} 1251