SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/sunrpc/clnt.c

   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  *  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/smp_lock.h>
  31 #include <linux/utsname.h>
  32 #include <linux/workqueue.h>
  33
  34 #include <linux/sunrpc/clnt.h>
  35 #include <linux/sunrpc/rpc_pipe_fs.h>
  36 #include <linux/sunrpc/metrics.h>
  37
  38
  39 #ifdef RPC_DEBUG
  40 # define RPCDBG_FACILITY        RPCDBG_CALL
  41 #endif
  42
  43 #define dprint_status(t)                                        \
  44         dprintk("RPC: %5u %s (status %d)\n", t->tk_pid,         \
  45                         __FUNCTION__, t->tk_status)
  46
  47 /*
  48  * All RPC clients are linked into this list
  49  */
  50 static LIST_HEAD(all_clients);
  51 static DEFINE_SPINLOCK(rpc_client_lock);
  52
  53 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
  54
  55
  56 static void     call_start(struct rpc_task *task);
  57 static void     call_reserve(struct rpc_task *task);
  58 static void     call_reserveresult(struct rpc_task *task);
  59 static void     call_allocate(struct rpc_task *task);
  60 static void     call_encode(struct rpc_task *task);
  61 static void     call_decode(struct rpc_task *task);
  62 static void     call_bind(struct rpc_task *task);
  63 static void     call_bind_status(struct rpc_task *task);
  64 static void     call_transmit(struct rpc_task *task);
  65 static void     call_status(struct rpc_task *task);
  66 static void     call_transmit_status(struct rpc_task *task);
  67 static void     call_refresh(struct rpc_task *task);
  68 static void     call_refreshresult(struct rpc_task *task);
  69 static void     call_timeout(struct rpc_task *task);
  70 static void     call_connect(struct rpc_task *task);
  71 static void     call_connect_status(struct rpc_task *task);
  72 static __be32 * call_header(struct rpc_task *task);
  73 static __be32 * call_verify(struct rpc_task *task);
  74
  75 static int      rpc_ping(struct rpc_clnt *clnt, int flags);
  76
  77 static void rpc_register_client(struct rpc_clnt *clnt)
  78 {
  79         spin_lock(&rpc_client_lock);
  80         list_add(&clnt->cl_clients, &all_clients);
  81         spin_unlock(&rpc_client_lock);
  82 }
  83
  84 static void rpc_unregister_client(struct rpc_clnt *clnt)
  85 {
  86         spin_lock(&rpc_client_lock);
  87         list_del(&clnt->cl_clients);
  88         spin_unlock(&rpc_client_lock);
  89 }
  90
  91 static int
  92 rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
  93 {
  94         static uint32_t clntid;
  95         int error;
  96
  97         clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
  98         clnt->cl_dentry = ERR_PTR(-ENOENT);
  99         if (dir_name == NULL)
 100                 return 0;
 101
 102         clnt->cl_vfsmnt = rpc_get_mount();
 103         if (IS_ERR(clnt->cl_vfsmnt))
 104                 return PTR_ERR(clnt->cl_vfsmnt);
 105
 106         for (;;) {
 107                 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
 108                                 "%s/clnt%x", dir_name,
 109                                 (unsigned int)clntid++);
 110                 clnt->cl_pathname[sizeof(clnt->cl_pathname) - 1] = '\0';
 111                 clnt->cl_dentry = rpc_mkdir(clnt->cl_pathname, clnt);
 112                 if (!IS_ERR(clnt->cl_dentry))
 113                         return 0;
 114                 error = PTR_ERR(clnt->cl_dentry);
 115                 if (error != -EEXIST) {
 116                         printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
 117                                         clnt->cl_pathname, error);
 118                         rpc_put_mount();
 119                         return error;
 120                 }
 121         }
 122 }
 123
 124 static struct rpc_clnt * rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *program, u32 vers, rpc_authflavor_t flavor)
 125 {
 126         struct rpc_version      *version;
 127         struct rpc_clnt         *clnt = NULL;
 128         struct rpc_auth         *auth;
 129         int err;
 130         int len;
 131
 132         dprintk("RPC:       creating %s client for %s (xprt %p)\n",
 133                         program->name, servname, xprt);
 134
 135         err = rpciod_up();
 136         if (err)
 137                 goto out_no_rpciod;
 138         err = -EINVAL;
 139         if (!xprt)
 140                 goto out_no_xprt;
 141         if (vers >= program->nrvers || !(version = program->version[vers]))
 142                 goto out_err;
 143
 144         err = -ENOMEM;
 145         clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
 146         if (!clnt)
 147                 goto out_err;
 148         clnt->cl_parent = clnt;
 149
 150         clnt->cl_server = clnt->cl_inline_name;
 151         len = strlen(servname) + 1;
 152         if (len > sizeof(clnt->cl_inline_name)) {
 153                 char *buf = kmalloc(len, GFP_KERNEL);
 154                 if (buf != 0)
 155                         clnt->cl_server = buf;
 156                 else
 157                         len = sizeof(clnt->cl_inline_name);
 158         }
 159         strlcpy(clnt->cl_server, servname, len);
 160
 161         clnt->cl_xprt     = xprt;
 162         clnt->cl_procinfo = version->procs;
 163         clnt->cl_maxproc  = version->nrprocs;
 164         clnt->cl_protname = program->name;
 165         clnt->cl_prog     = program->number;
 166         clnt->cl_vers     = version->number;
 167         clnt->cl_stats    = program->stats;
 168         clnt->cl_metrics  = rpc_alloc_iostats(clnt);
 169         err = -ENOMEM;
 170         if (clnt->cl_metrics == NULL)
 171                 goto out_no_stats;
 172         clnt->cl_program  = program;
 173         INIT_LIST_HEAD(&clnt->cl_tasks);
 174         spin_lock_init(&clnt->cl_lock);
 175
 176         if (!xprt_bound(clnt->cl_xprt))
 177                 clnt->cl_autobind = 1;
 178
 179         clnt->cl_rtt = &clnt->cl_rtt_default;
 180         rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
 181
 182         kref_init(&clnt->cl_kref);
 183
 184         err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
 185         if (err < 0)
 186                 goto out_no_path;
 187
 188         auth = rpcauth_create(flavor, clnt);
 189         if (IS_ERR(auth)) {
 190                 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
 191                                 flavor);
 192                 err = PTR_ERR(auth);
 193                 goto out_no_auth;
 194         }
 195
 196         /* save the nodename */
 197         clnt->cl_nodelen = strlen(utsname()->nodename);
 198         if (clnt->cl_nodelen > UNX_MAXNODENAME)
 199                 clnt->cl_nodelen = UNX_MAXNODENAME;
 200         memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
 201         rpc_register_client(clnt);
 202         return clnt;
 203
 204 out_no_auth:
 205         if (!IS_ERR(clnt->cl_dentry)) {
 206                 rpc_rmdir(clnt->cl_dentry);
 207                 rpc_put_mount();
 208         }
 209 out_no_path:
 210         rpc_free_iostats(clnt->cl_metrics);
 211 out_no_stats:
 212         if (clnt->cl_server != clnt->cl_inline_name)
 213                 kfree(clnt->cl_server);
 214         kfree(clnt);
 215 out_err:
 216         xprt_put(xprt);
 217 out_no_xprt:
 218         rpciod_down();
 219 out_no_rpciod:
 220         return ERR_PTR(err);
 221 }
 222
 223 /*
 224  * rpc_create - create an RPC client and transport with one call
 225  * @args: rpc_clnt create argument structure
 226  *
 227  * Creates and initializes an RPC transport and an RPC client.
 228  *
 229  * It can ping the server in order to determine if it is up, and to see if
 230  * it supports this program and version.  RPC_CLNT_CREATE_NOPING disables
 231  * this behavior so asynchronous tasks can also use rpc_create.
 232  */
 233 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
 234 {
 235         struct rpc_xprt *xprt;
 236         struct rpc_clnt *clnt;
 237         struct rpc_xprtsock_create xprtargs = {
 238                 .proto = args->protocol,
 239                 .srcaddr = args->saddress,
 240                 .dstaddr = args->address,
 241                 .addrlen = args->addrsize,
 242                 .timeout = args->timeout
 243         };
 244         char servername[20];
 245
 246         xprt = xprt_create_transport(&xprtargs);
 247         if (IS_ERR(xprt))
 248                 return (struct rpc_clnt *)xprt;
 249
 250         /*
 251          * If the caller chooses not to specify a hostname, whip
 252          * up a string representation of the passed-in address.
 253          */
 254         if (args->servername == NULL) {
 255                 struct sockaddr_in *addr =
 256                                         (struct sockaddr_in *) &args->address;
 257                 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
 258                         NIPQUAD(addr->sin_addr.s_addr));
 259                 args->servername = servername;
 260         }
 261
 262         /*
 263          * By default, kernel RPC client connects from a reserved port.
 264          * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
 265          * but it is always enabled for rpciod, which handles the connect
 266          * operation.
 267          */
 268         xprt->resvport = 1;
 269         if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
 270                 xprt->resvport = 0;
 271
 272         clnt = rpc_new_client(xprt, args->servername, args->program,
 273                                 args->version, args->authflavor);
 274         if (IS_ERR(clnt))
 275                 return clnt;
 276
 277         if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
 278                 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
 279                 if (err != 0) {
 280                         rpc_shutdown_client(clnt);
 281                         return ERR_PTR(err);
 282                 }
 283         }
 284
 285         clnt->cl_softrtry = 1;
 286         if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
 287                 clnt->cl_softrtry = 0;
 288
 289         if (args->flags & RPC_CLNT_CREATE_INTR)
 290                 clnt->cl_intr = 1;
 291         if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
 292                 clnt->cl_autobind = 1;
 293         if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
 294                 clnt->cl_discrtry = 1;
 295
 296         return clnt;
 297 }
 298 EXPORT_SYMBOL_GPL(rpc_create);
 299
 300 /*
 301  * This function clones the RPC client structure. It allows us to share the
 302  * same transport while varying parameters such as the authentication
 303  * flavour.
 304  */
 305 struct rpc_clnt *
 306 rpc_clone_client(struct rpc_clnt *clnt)
 307 {
 308         struct rpc_clnt *new;
 309         int err = -ENOMEM;
 310
 311         new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
 312         if (!new)
 313                 goto out_no_clnt;
 314         new->cl_parent = clnt;
 315         /* Turn off autobind on clones */
 316         new->cl_autobind = 0;
 317         INIT_LIST_HEAD(&new->cl_tasks);
 318         spin_lock_init(&new->cl_lock);
 319         rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
 320         new->cl_metrics = rpc_alloc_iostats(clnt);
 321         if (new->cl_metrics == NULL)
 322                 goto out_no_stats;
 323         kref_init(&new->cl_kref);
 324         err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
 325         if (err != 0)
 326                 goto out_no_path;
 327         if (new->cl_auth)
 328                 atomic_inc(&new->cl_auth->au_count);
 329         xprt_get(clnt->cl_xprt);
 330         kref_get(&clnt->cl_kref);
 331         rpc_register_client(new);
 332         rpciod_up();
 333         return new;
 334 out_no_path:
 335         rpc_free_iostats(new->cl_metrics);
 336 out_no_stats:
 337         kfree(new);
 338 out_no_clnt:
 339         dprintk("RPC:       %s: returned error %d\n", __FUNCTION__, err);
 340         return ERR_PTR(err);
 341 }
 342
 343 /*
 344  * Properly shut down an RPC client, terminating all outstanding
 345  * requests.
 346  */
 347 void rpc_shutdown_client(struct rpc_clnt *clnt)
 348 {
 349         dprintk("RPC:       shutting down %s client for %s\n",
 350                         clnt->cl_protname, clnt->cl_server);
 351
 352         while (!list_empty(&clnt->cl_tasks)) {
 353                 rpc_killall_tasks(clnt);
 354                 wait_event_timeout(destroy_wait,
 355                         list_empty(&clnt->cl_tasks), 1*HZ);
 356         }
 357
 358         rpc_release_client(clnt);
 359 }
 360
 361 /*
 362  * Free an RPC client
 363  */
 364 static void
 365 rpc_free_client(struct kref *kref)
 366 {
 367         struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
 368
 369         dprintk("RPC:       destroying %s client for %s\n",
 370                         clnt->cl_protname, clnt->cl_server);
 371         if (!IS_ERR(clnt->cl_dentry)) {
 372                 rpc_rmdir(clnt->cl_dentry);
 373                 rpc_put_mount();
 374         }
 375         if (clnt->cl_parent != clnt) {
 376                 rpc_release_client(clnt->cl_parent);
 377                 goto out_free;
 378         }
 379         if (clnt->cl_server != clnt->cl_inline_name)
 380                 kfree(clnt->cl_server);
 381 out_free:
 382         rpc_unregister_client(clnt);
 383         rpc_free_iostats(clnt->cl_metrics);
 384         clnt->cl_metrics = NULL;
 385         xprt_put(clnt->cl_xprt);
 386         rpciod_down();
 387         kfree(clnt);
 388 }
 389
 390 /*
 391  * Free an RPC client
 392  */
 393 static void
 394 rpc_free_auth(struct kref *kref)
 395 {
 396         struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
 397
 398         if (clnt->cl_auth == NULL) {
 399                 rpc_free_client(kref);
 400                 return;
 401         }
 402
 403         /*
 404          * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
 405          *       release remaining GSS contexts. This mechanism ensures
 406          *       that it can do so safely.
 407          */
 408         kref_init(kref);
 409         rpcauth_release(clnt->cl_auth);
 410         clnt->cl_auth = NULL;
 411         kref_put(kref, rpc_free_client);
 412 }
 413
 414 /*
 415  * Release reference to the RPC client
 416  */
 417 void
 418 rpc_release_client(struct rpc_clnt *clnt)
 419 {
 420         dprintk("RPC:       rpc_release_client(%p)\n", clnt);
 421
 422         if (list_empty(&clnt->cl_tasks))
 423                 wake_up(&destroy_wait);
 424         kref_put(&clnt->cl_kref, rpc_free_auth);
 425 }
 426
 427 /**
 428  * rpc_bind_new_program - bind a new RPC program to an existing client
 429  * @old - old rpc_client
 430  * @program - rpc program to set
 431  * @vers - rpc program version
 432  *
 433  * Clones the rpc client and sets up a new RPC program. This is mainly
 434  * of use for enabling different RPC programs to share the same transport.
 435  * The Sun NFSv2/v3 ACL protocol can do this.
 436  */
 437 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
 438                                       struct rpc_program *program,
 439                                       u32 vers)
 440 {
 441         struct rpc_clnt *clnt;
 442         struct rpc_version *version;
 443         int err;
 444
 445         BUG_ON(vers >= program->nrvers || !program->version[vers]);
 446         version = program->version[vers];
 447         clnt = rpc_clone_client(old);
 448         if (IS_ERR(clnt))
 449                 goto out;
 450         clnt->cl_procinfo = version->procs;
 451         clnt->cl_maxproc  = version->nrprocs;
 452         clnt->cl_protname = program->name;
 453         clnt->cl_prog     = program->number;
 454         clnt->cl_vers     = version->number;
 455         clnt->cl_stats    = program->stats;
 456         err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
 457         if (err != 0) {
 458                 rpc_shutdown_client(clnt);
 459                 clnt = ERR_PTR(err);
 460         }
 461 out:
 462         return clnt;
 463 }
 464
 465 /*
 466  * Default callback for async RPC calls
 467  */
 468 static void
 469 rpc_default_callback(struct rpc_task *task, void *data)
 470 {
 471 }
 472
 473 static const struct rpc_call_ops rpc_default_ops = {
 474         .rpc_call_done = rpc_default_callback,
 475 };
 476
 477 /*
 478  *      Export the signal mask handling for synchronous code that
 479  *      sleeps on RPC calls
 480  */
 481 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
 482
 483 static void rpc_save_sigmask(sigset_t *oldset, int intr)
 484 {
 485         unsigned long   sigallow = sigmask(SIGKILL);
 486         sigset_t sigmask;
 487
 488         /* Block all signals except those listed in sigallow */
 489         if (intr)
 490                 sigallow |= RPC_INTR_SIGNALS;
 491         siginitsetinv(&sigmask, sigallow);
 492         sigprocmask(SIG_BLOCK, &sigmask, oldset);
 493 }
 494
 495 static inline void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
 496 {
 497         rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
 498 }
 499
 500 static inline void rpc_restore_sigmask(sigset_t *oldset)
 501 {
 502         sigprocmask(SIG_SETMASK, oldset, NULL);
 503 }
 504
 505 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
 506 {
 507         rpc_save_sigmask(oldset, clnt->cl_intr);
 508 }
 509
 510 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
 511 {
 512         rpc_restore_sigmask(oldset);
 513 }
 514
 515 static
 516 struct rpc_task *rpc_do_run_task(struct rpc_clnt *clnt,
 517                 struct rpc_message *msg,
 518                 int flags,
 519                 const struct rpc_call_ops *ops,
 520                 void *data)
 521 {
 522         struct rpc_task *task, *ret;
 523         sigset_t oldset;
 524
 525         task = rpc_new_task(clnt, flags, ops, data);
 526         if (task == NULL) {
 527                 rpc_release_calldata(ops, data);
 528                 return ERR_PTR(-ENOMEM);
 529         }
 530
 531         /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
 532         rpc_task_sigmask(task, &oldset);
 533         if (msg != NULL) {
 534                 rpc_call_setup(task, msg, 0);
 535                 if (task->tk_status != 0) {
 536                         ret = ERR_PTR(task->tk_status);
 537                         rpc_put_task(task);
 538                         goto out;
 539                 }
 540         }
 541         atomic_inc(&task->tk_count);
 542         rpc_execute(task);
 543         ret = task;
 544 out:
 545         rpc_restore_sigmask(&oldset);
 546         return ret;
 547 }
 548
 549 /**
 550  * rpc_call_sync - Perform a synchronous RPC call
 551  * @clnt: pointer to RPC client
 552  * @msg: RPC call parameters
 553  * @flags: RPC call flags
 554  */
 555 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
 556 {
 557         struct rpc_task *task;
 558         int status;
 559
 560         BUG_ON(flags & RPC_TASK_ASYNC);
 561
 562         task = rpc_do_run_task(clnt, msg, flags, &rpc_default_ops, NULL);
 563         if (IS_ERR(task))
 564                 return PTR_ERR(task);
 565         status = task->tk_status;
 566         rpc_put_task(task);
 567         return status;
 568 }
 569
 570 /**
 571  * rpc_call_async - Perform an asynchronous RPC call
 572  * @clnt: pointer to RPC client
 573  * @msg: RPC call parameters
 574  * @flags: RPC call flags
 575  * @ops: RPC call ops
 576  * @data: user call data
 577  */
 578 int
 579 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
 580                const struct rpc_call_ops *tk_ops, void *data)
 581 {
 582         struct rpc_task *task;
 583
 584         task = rpc_do_run_task(clnt, msg, flags|RPC_TASK_ASYNC, tk_ops, data);
 585         if (IS_ERR(task))
 586                 return PTR_ERR(task);
 587         rpc_put_task(task);
 588         return 0;
 589 }
 590
 591 /**
 592  * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
 593  * @clnt: pointer to RPC client
 594  * @flags: RPC flags
 595  * @ops: RPC call ops
 596  * @data: user call data
 597  */
 598 struct rpc_task *rpc_run_task(struct rpc_clnt *clnt, int flags,
 599                                         const struct rpc_call_ops *tk_ops,
 600                                         void *data)
 601 {
 602         return rpc_do_run_task(clnt, NULL, flags, tk_ops, data);
 603 }
 604 EXPORT_SYMBOL(rpc_run_task);
 605
 606 void
 607 rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
 608 {
 609         task->tk_msg   = *msg;
 610         task->tk_flags |= flags;
 611         /* Bind the user cred */
 612         if (task->tk_msg.rpc_cred != NULL)
 613                 rpcauth_holdcred(task);
 614         else
 615                 rpcauth_bindcred(task);
 616
 617         if (task->tk_status == 0)
 618                 task->tk_action = call_start;
 619         else
 620                 task->tk_action = rpc_exit_task;
 621 }
 622
 623 /**
 624  * rpc_peeraddr - extract remote peer address from clnt's xprt
 625  * @clnt: RPC client structure
 626  * @buf: target buffer
 627  * @size: length of target buffer
 628  *
 629  * Returns the number of bytes that are actually in the stored address.
 630  */
 631 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
 632 {
 633         size_t bytes;
 634         struct rpc_xprt *xprt = clnt->cl_xprt;
 635
 636         bytes = sizeof(xprt->addr);
 637         if (bytes > bufsize)
 638                 bytes = bufsize;
 639         memcpy(buf, &clnt->cl_xprt->addr, bytes);
 640         return xprt->addrlen;
 641 }
 642 EXPORT_SYMBOL_GPL(rpc_peeraddr);
 643
 644 /**
 645  * rpc_peeraddr2str - return remote peer address in printable format
 646  * @clnt: RPC client structure
 647  * @format: address format
 648  *
 649  */
 650 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
 651 {
 652         struct rpc_xprt *xprt = clnt->cl_xprt;
 653
 654         if (xprt->address_strings[format] != NULL)
 655                 return xprt->address_strings[format];
 656         else
 657                 return "unprintable";
 658 }
 659 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
 660
 661 void
 662 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
 663 {
 664         struct rpc_xprt *xprt = clnt->cl_xprt;
 665         if (xprt->ops->set_buffer_size)
 666                 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
 667 }
 668
 669 /*
 670  * Return size of largest payload RPC client can support, in bytes
 671  *
 672  * For stream transports, this is one RPC record fragment (see RFC
 673  * 1831), as we don't support multi-record requests yet.  For datagram
 674  * transports, this is the size of an IP packet minus the IP, UDP, and
 675  * RPC header sizes.
 676  */
 677 size_t rpc_max_payload(struct rpc_clnt *clnt)
 678 {
 679         return clnt->cl_xprt->max_payload;
 680 }
 681 EXPORT_SYMBOL_GPL(rpc_max_payload);
 682
 683 /**
 684  * rpc_force_rebind - force transport to check that remote port is unchanged
 685  * @clnt: client to rebind
 686  *
 687  */
 688 void rpc_force_rebind(struct rpc_clnt *clnt)
 689 {
 690         if (clnt->cl_autobind)
 691                 xprt_clear_bound(clnt->cl_xprt);
 692 }
 693 EXPORT_SYMBOL_GPL(rpc_force_rebind);
 694
 695 /*
 696  * Restart an (async) RPC call. Usually called from within the
 697  * exit handler.
 698  */
 699 void
 700 rpc_restart_call(struct rpc_task *task)
 701 {
 702         if (RPC_ASSASSINATED(task))
 703                 return;
 704
 705         task->tk_action = call_start;
 706 }
 707
 708 /*
 709  * 0.  Initial state
 710  *
 711  *     Other FSM states can be visited zero or more times, but
 712  *     this state is visited exactly once for each RPC.
 713  */
 714 static void
 715 call_start(struct rpc_task *task)
 716 {
 717         struct rpc_clnt *clnt = task->tk_client;
 718
 719         dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
 720                         clnt->cl_protname, clnt->cl_vers,
 721                         task->tk_msg.rpc_proc->p_proc,
 722                         (RPC_IS_ASYNC(task) ? "async" : "sync"));
 723
 724         /* Increment call count */
 725         task->tk_msg.rpc_proc->p_count++;
 726         clnt->cl_stats->rpccnt++;
 727         task->tk_action = call_reserve;
 728 }
 729
 730 /*
 731  * 1.   Reserve an RPC call slot
 732  */
 733 static void
 734 call_reserve(struct rpc_task *task)
 735 {
 736         dprint_status(task);
 737
 738         if (!rpcauth_uptodatecred(task)) {
 739                 task->tk_action = call_refresh;
 740                 return;
 741         }
 742
 743         task->tk_status  = 0;
 744         task->tk_action  = call_reserveresult;
 745         xprt_reserve(task);
 746 }
 747
 748 /*
 749  * 1b.  Grok the result of xprt_reserve()
 750  */
 751 static void
 752 call_reserveresult(struct rpc_task *task)
 753 {
 754         int status = task->tk_status;
 755
 756         dprint_status(task);
 757
 758         /*
 759          * After a call to xprt_reserve(), we must have either
 760          * a request slot or else an error status.
 761          */
 762         task->tk_status = 0;
 763         if (status >= 0) {
 764                 if (task->tk_rqstp) {
 765                         task->tk_action = call_allocate;
 766                         return;
 767                 }
 768
 769                 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
 770                                 __FUNCTION__, status);
 771                 rpc_exit(task, -EIO);
 772                 return;
 773         }
 774
 775         /*
 776          * Even though there was an error, we may have acquired
 777          * a request slot somehow.  Make sure not to leak it.
 778          */
 779         if (task->tk_rqstp) {
 780                 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
 781                                 __FUNCTION__, status);
 782                 xprt_release(task);
 783         }
 784
 785         switch (status) {
 786         case -EAGAIN:   /* woken up; retry */
 787                 task->tk_action = call_reserve;
 788                 return;
 789         case -EIO:      /* probably a shutdown */
 790                 break;
 791         default:
 792                 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
 793                                 __FUNCTION__, status);
 794                 break;
 795         }
 796         rpc_exit(task, status);
 797 }
 798
 799 /*
 800  * 2.   Allocate the buffer. For details, see sched.c:rpc_malloc.
 801  *      (Note: buffer memory is freed in xprt_release).
 802  */
 803 static void
 804 call_allocate(struct rpc_task *task)
 805 {
 806         unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
 807         struct rpc_rqst *req = task->tk_rqstp;
 808         struct rpc_xprt *xprt = task->tk_xprt;
 809         struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
 810
 811         dprint_status(task);
 812
 813         task->tk_status = 0;
 814         task->tk_action = call_bind;
 815
 816         if (req->rq_buffer)
 817                 return;
 818
 819         if (proc->p_proc != 0) {
 820                 BUG_ON(proc->p_arglen == 0);
 821                 if (proc->p_decode != NULL)
 822                         BUG_ON(proc->p_replen == 0);
 823         }
 824
 825         /*
 826          * Calculate the size (in quads) of the RPC call
 827          * and reply headers, and convert both values
 828          * to byte sizes.
 829          */
 830         req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
 831         req->rq_callsize <<= 2;
 832         req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
 833         req->rq_rcvsize <<= 2;
 834
 835         req->rq_buffer = xprt->ops->buf_alloc(task,
 836                                         req->rq_callsize + req->rq_rcvsize);
 837         if (req->rq_buffer != NULL)
 838                 return;
 839
 840         dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
 841
 842         if (RPC_IS_ASYNC(task) || !signalled()) {
 843                 xprt_release(task);
 844                 task->tk_action = call_reserve;
 845                 rpc_delay(task, HZ>>4);
 846                 return;
 847         }
 848
 849         rpc_exit(task, -ERESTARTSYS);
 850 }
 851
 852 static inline int
 853 rpc_task_need_encode(struct rpc_task *task)
 854 {
 855         return task->tk_rqstp->rq_snd_buf.len == 0;
 856 }
 857
 858 static inline void
 859 rpc_task_force_reencode(struct rpc_task *task)
 860 {
 861         task->tk_rqstp->rq_snd_buf.len = 0;
 862 }
 863
 864 static inline void
 865 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
 866 {
 867         buf->head[0].iov_base = start;
 868         buf->head[0].iov_len = len;
 869         buf->tail[0].iov_len = 0;
 870         buf->page_len = 0;
 871         buf->len = 0;
 872         buf->buflen = len;
 873 }
 874
 875 /*
 876  * 3.   Encode arguments of an RPC call
 877  */
 878 static void
 879 call_encode(struct rpc_task *task)
 880 {
 881         struct rpc_rqst *req = task->tk_rqstp;
 882         kxdrproc_t      encode;
 883         __be32          *p;
 884
 885         dprint_status(task);
 886
 887         rpc_xdr_buf_init(&req->rq_snd_buf,
 888                          req->rq_buffer,
 889                          req->rq_callsize);
 890         rpc_xdr_buf_init(&req->rq_rcv_buf,
 891                          (char *)req->rq_buffer + req->rq_callsize,
 892                          req->rq_rcvsize);
 893
 894         /* Encode header and provided arguments */
 895         encode = task->tk_msg.rpc_proc->p_encode;
 896         if (!(p = call_header(task))) {
 897                 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
 898                 rpc_exit(task, -EIO);
 899                 return;
 900         }
 901         if (encode == NULL)
 902                 return;
 903
 904         task->tk_status = rpcauth_wrap_req(task, encode, req, p,
 905                         task->tk_msg.rpc_argp);
 906         if (task->tk_status == -ENOMEM) {
 907                 /* XXX: Is this sane? */
 908                 rpc_delay(task, 3*HZ);
 909                 task->tk_status = -EAGAIN;
 910         }
 911 }
 912
 913 /*
 914  * 4.   Get the server port number if not yet set
 915  */
 916 static void
 917 call_bind(struct rpc_task *task)
 918 {
 919         struct rpc_xprt *xprt = task->tk_xprt;
 920
 921         dprint_status(task);
 922
 923         task->tk_action = call_connect;
 924         if (!xprt_bound(xprt)) {
 925                 task->tk_action = call_bind_status;
 926                 task->tk_timeout = xprt->bind_timeout;
 927                 xprt->ops->rpcbind(task);
 928         }
 929 }
 930
 931 /*
 932  * 4a.  Sort out bind result
 933  */
 934 static void
 935 call_bind_status(struct rpc_task *task)
 936 {
 937         int status = -EACCES;
 938
 939         if (task->tk_status >= 0) {
 940                 dprint_status(task);
 941                 task->tk_status = 0;
 942                 task->tk_action = call_connect;
 943                 return;
 944         }
 945
 946         switch (task->tk_status) {
 947         case -EACCES:
 948                 dprintk("RPC: %5u remote rpcbind: RPC program/version "
 949                                 "unavailable\n", task->tk_pid);
 950                 rpc_delay(task, 3*HZ);
 951                 goto retry_timeout;
 952         case -ETIMEDOUT:
 953                 dprintk("RPC: %5u rpcbind request timed out\n",
 954                                 task->tk_pid);
 955                 goto retry_timeout;
 956         case -EPFNOSUPPORT:
 957                 dprintk("RPC: %5u remote rpcbind service unavailable\n",
 958                                 task->tk_pid);
 959                 break;
 960         case -EPROTONOSUPPORT:
 961                 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
 962                                 task->tk_pid);
 963                 task->tk_status = 0;
 964                 task->tk_action = call_bind;
 965                 return;
 966         default:
 967                 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
 968                                 task->tk_pid, -task->tk_status);
 969                 status = -EIO;
 970         }
 971
 972         rpc_exit(task, status);
 973         return;
 974
 975 retry_timeout:
 976         task->tk_action = call_timeout;
 977 }
 978
 979 /*
 980  * 4b.  Connect to the RPC server
 981  */
 982 static void
 983 call_connect(struct rpc_task *task)
 984 {
 985         struct rpc_xprt *xprt = task->tk_xprt;
 986
 987         dprintk("RPC: %5u call_connect xprt %p %s connected\n",
 988                         task->tk_pid, xprt,
 989                         (xprt_connected(xprt) ? "is" : "is not"));
 990
 991         task->tk_action = call_transmit;
 992         if (!xprt_connected(xprt)) {
 993                 task->tk_action = call_connect_status;
 994                 if (task->tk_status < 0)
 995                         return;
 996                 xprt_connect(task);
 997         }
 998 }
 999
1000 /*
1001  * 4c.  Sort out connect result
1002  */
1003 static void
1004 call_connect_status(struct rpc_task *task)
1005 {
1006         struct rpc_clnt *clnt = task->tk_client;
1007         int status = task->tk_status;
1008
1009         dprint_status(task);
1010
1011         task->tk_status = 0;
1012         if (status >= 0) {
1013                 clnt->cl_stats->netreconn++;
1014                 task->tk_action = call_transmit;
1015                 return;
1016         }
1017
1018         /* Something failed: remote service port may have changed */
1019         rpc_force_rebind(clnt);
1020
1021         switch (status) {
1022         case -ENOTCONN:
1023         case -EAGAIN:
1024                 task->tk_action = call_bind;
1025                 if (!RPC_IS_SOFT(task))
1026                         return;
1027                 /* if soft mounted, test if we've timed out */
1028         case -ETIMEDOUT:
1029                 task->tk_action = call_timeout;
1030                 return;
1031         }
1032         rpc_exit(task, -EIO);
1033 }
1034
1035 /*
1036  * 5.   Transmit the RPC request, and wait for reply
1037  */
1038 static void
1039 call_transmit(struct rpc_task *task)
1040 {
1041         dprint_status(task);
1042
1043         task->tk_action = call_status;
1044         if (task->tk_status < 0)
1045                 return;
1046         task->tk_status = xprt_prepare_transmit(task);
1047         if (task->tk_status != 0)
1048                 return;
1049         task->tk_action = call_transmit_status;
1050         /* Encode here so that rpcsec_gss can use correct sequence number. */
1051         if (rpc_task_need_encode(task)) {
1052                 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1053                 call_encode(task);
1054                 /* Did the encode result in an error condition? */
1055                 if (task->tk_status != 0)
1056                         return;
1057         }
1058         xprt_transmit(task);
1059         if (task->tk_status < 0)
1060                 return;
1061         /*
1062          * On success, ensure that we call xprt_end_transmit() before sleeping
1063          * in order to allow access to the socket to other RPC requests.
1064          */
1065         call_transmit_status(task);
1066         if (task->tk_msg.rpc_proc->p_decode != NULL)
1067                 return;
1068         task->tk_action = rpc_exit_task;
1069         rpc_wake_up_task(task);
1070 }
1071
1072 /*
1073  * 5a.  Handle cleanup after a transmission
1074  */
1075 static void
1076 call_transmit_status(struct rpc_task *task)
1077 {
1078         task->tk_action = call_status;
1079         /*
1080          * Special case: if we've been waiting on the socket's write_space()
1081          * callback, then don't call xprt_end_transmit().
1082          */
1083         if (task->tk_status == -EAGAIN)
1084                 return;
1085         xprt_end_transmit(task);
1086         rpc_task_force_reencode(task);
1087 }
1088
1089 /*
1090  * 6.   Sort out the RPC call status
1091  */
1092 static void
1093 call_status(struct rpc_task *task)
1094 {
1095         struct rpc_clnt *clnt = task->tk_client;
1096         struct rpc_rqst *req = task->tk_rqstp;
1097         int             status;
1098
1099         if (req->rq_received > 0 && !req->rq_bytes_sent)
1100                 task->tk_status = req->rq_received;
1101
1102         dprint_status(task);
1103
1104         status = task->tk_status;
1105         if (status >= 0) {
1106                 task->tk_action = call_decode;
1107                 return;
1108         }
1109
1110         task->tk_status = 0;
1111         switch(status) {
1112         case -EHOSTDOWN:
1113         case -EHOSTUNREACH:
1114         case -ENETUNREACH:
1115                 /*
1116                  * Delay any retries for 3 seconds, then handle as if it
1117                  * were a timeout.
1118                  */
1119                 rpc_delay(task, 3*HZ);
1120         case -ETIMEDOUT:
1121                 task->tk_action = call_timeout;
1122                 if (task->tk_client->cl_discrtry)
1123                         xprt_disconnect(task->tk_xprt);
1124                 break;
1125         case -ECONNREFUSED:
1126         case -ENOTCONN:
1127                 rpc_force_rebind(clnt);
1128                 task->tk_action = call_bind;
1129                 break;
1130         case -EAGAIN:
1131                 task->tk_action = call_transmit;
1132                 break;
1133         case -EIO:
1134                 /* shutdown or soft timeout */
1135                 rpc_exit(task, status);
1136                 break;
1137         default:
1138                 printk("%s: RPC call returned error %d\n",
1139                                clnt->cl_protname, -status);
1140                 rpc_exit(task, status);
1141         }
1142 }
1143
1144 /*
1145  * 6a.  Handle RPC timeout
1146  *      We do not release the request slot, so we keep using the
1147  *      same XID for all retransmits.
1148  */
1149 static void
1150 call_timeout(struct rpc_task *task)
1151 {
1152         struct rpc_clnt *clnt = task->tk_client;
1153
1154         if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1155                 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1156                 goto retry;
1157         }
1158
1159         dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1160         task->tk_timeouts++;
1161
1162         if (RPC_IS_SOFT(task)) {
1163                 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1164                                 clnt->cl_protname, clnt->cl_server);
1165                 rpc_exit(task, -EIO);
1166                 return;
1167         }
1168
1169         if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1170                 task->tk_flags |= RPC_CALL_MAJORSEEN;
1171                 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1172                         clnt->cl_protname, clnt->cl_server);
1173         }
1174         rpc_force_rebind(clnt);
1175
1176 retry:
1177         clnt->cl_stats->rpcretrans++;
1178         task->tk_action = call_bind;
1179         task->tk_status = 0;
1180 }
1181
1182 /*
1183  * 7.   Decode the RPC reply
1184  */
1185 static void
1186 call_decode(struct rpc_task *task)
1187 {
1188         struct rpc_clnt *clnt = task->tk_client;
1189         struct rpc_rqst *req = task->tk_rqstp;
1190         kxdrproc_t      decode = task->tk_msg.rpc_proc->p_decode;
1191         __be32          *p;
1192
1193         dprintk("RPC: %5u call_decode (status %d)\n",
1194                         task->tk_pid, task->tk_status);
1195
1196         if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1197                 printk(KERN_NOTICE "%s: server %s OK\n",
1198                         clnt->cl_protname, clnt->cl_server);
1199                 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1200         }
1201
1202         if (task->tk_status < 12) {
1203                 if (!RPC_IS_SOFT(task)) {
1204                         task->tk_action = call_bind;
1205                         clnt->cl_stats->rpcretrans++;
1206                         goto out_retry;
1207                 }
1208                 dprintk("RPC:       %s: too small RPC reply size (%d bytes)\n",
1209                                 clnt->cl_protname, task->tk_status);
1210                 task->tk_action = call_timeout;
1211                 goto out_retry;
1212         }
1213
1214         /*
1215          * Ensure that we see all writes made by xprt_complete_rqst()
1216          * before it changed req->rq_received.
1217          */
1218         smp_rmb();
1219         req->rq_rcv_buf.len = req->rq_private_buf.len;
1220
1221         /* Check that the softirq receive buffer is valid */
1222         WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1223                                 sizeof(req->rq_rcv_buf)) != 0);
1224
1225         /* Verify the RPC header */
1226         p = call_verify(task);
1227         if (IS_ERR(p)) {
1228                 if (p == ERR_PTR(-EAGAIN))
1229                         goto out_retry;
1230                 return;
1231         }
1232
1233         task->tk_action = rpc_exit_task;
1234
1235         if (decode) {
1236                 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1237                                                       task->tk_msg.rpc_resp);
1238         }
1239         dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1240                         task->tk_status);
1241         return;
1242 out_retry:
1243         req->rq_received = req->rq_private_buf.len = 0;
1244         task->tk_status = 0;
1245         if (task->tk_client->cl_discrtry)
1246                 xprt_disconnect(task->tk_xprt);
1247 }
1248
1249 /*
1250  * 8.   Refresh the credentials if rejected by the server
1251  */
1252 static void
1253 call_refresh(struct rpc_task *task)
1254 {
1255         dprint_status(task);
1256
1257         xprt_release(task);     /* Must do to obtain new XID */
1258         task->tk_action = call_refreshresult;
1259         task->tk_status = 0;
1260         task->tk_client->cl_stats->rpcauthrefresh++;
1261         rpcauth_refreshcred(task);
1262 }
1263
1264 /*
1265  * 8a.  Process the results of a credential refresh
1266  */
1267 static void
1268 call_refreshresult(struct rpc_task *task)
1269 {
1270         int status = task->tk_status;
1271
1272         dprint_status(task);
1273
1274         task->tk_status = 0;
1275         task->tk_action = call_reserve;
1276         if (status >= 0 && rpcauth_uptodatecred(task))
1277                 return;
1278         if (status == -EACCES) {
1279                 rpc_exit(task, -EACCES);
1280                 return;
1281         }
1282         task->tk_action = call_refresh;
1283         if (status != -ETIMEDOUT)
1284                 rpc_delay(task, 3*HZ);
1285         return;
1286 }
1287
1288 /*
1289  * Call header serialization
1290  */
1291 static __be32 *
1292 call_header(struct rpc_task *task)
1293 {
1294         struct rpc_clnt *clnt = task->tk_client;
1295         struct rpc_rqst *req = task->tk_rqstp;
1296         __be32          *p = req->rq_svec[0].iov_base;
1297
1298         /* FIXME: check buffer size? */
1299
1300         p = xprt_skip_transport_header(task->tk_xprt, p);
1301         *p++ = req->rq_xid;             /* XID */
1302         *p++ = htonl(RPC_CALL);         /* CALL */
1303         *p++ = htonl(RPC_VERSION);      /* RPC version */
1304         *p++ = htonl(clnt->cl_prog);    /* program number */
1305         *p++ = htonl(clnt->cl_vers);    /* program version */
1306         *p++ = htonl(task->tk_msg.rpc_proc->p_proc);    /* procedure */
1307         p = rpcauth_marshcred(task, p);
1308         req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1309         return p;
1310 }
1311
1312 /*
1313  * Reply header verification
1314  */
1315 static __be32 *
1316 call_verify(struct rpc_task *task)
1317 {
1318         struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1319         int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1320         __be32  *p = iov->iov_base;
1321         u32 n;
1322         int error = -EACCES;
1323
1324         if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1325                 /* RFC-1014 says that the representation of XDR data must be a
1326                  * multiple of four bytes
1327                  * - if it isn't pointer subtraction in the NFS client may give
1328                  *   undefined results
1329                  */
1330                 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1331                        " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1332                        task->tk_rqstp->rq_rcv_buf.len);
1333                 goto out_eio;
1334         }
1335         if ((len -= 3) < 0)
1336                 goto out_overflow;
1337         p += 1; /* skip XID */
1338
1339         if ((n = ntohl(*p++)) != RPC_REPLY) {
1340                 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1341                                 task->tk_pid, __FUNCTION__, n);
1342                 goto out_garbage;
1343         }
1344         if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1345                 if (--len < 0)
1346                         goto out_overflow;
1347                 switch ((n = ntohl(*p++))) {
1348                         case RPC_AUTH_ERROR:
1349                                 break;
1350                         case RPC_MISMATCH:
1351                                 dprintk("RPC: %5u %s: RPC call version "
1352                                                 "mismatch!\n",
1353                                                 task->tk_pid, __FUNCTION__);
1354                                 error = -EPROTONOSUPPORT;
1355                                 goto out_err;
1356                         default:
1357                                 dprintk("RPC: %5u %s: RPC call rejected, "
1358                                                 "unknown error: %x\n",
1359                                                 task->tk_pid, __FUNCTION__, n);
1360                                 goto out_eio;
1361                 }
1362                 if (--len < 0)
1363                         goto out_overflow;
1364                 switch ((n = ntohl(*p++))) {
1365                 case RPC_AUTH_REJECTEDCRED:
1366                 case RPC_AUTH_REJECTEDVERF:
1367                 case RPCSEC_GSS_CREDPROBLEM:
1368                 case RPCSEC_GSS_CTXPROBLEM:
1369                         if (!task->tk_cred_retry)
1370                                 break;
1371                         task->tk_cred_retry--;
1372                         dprintk("RPC: %5u %s: retry stale creds\n",
1373                                         task->tk_pid, __FUNCTION__);
1374                         rpcauth_invalcred(task);
1375                         task->tk_action = call_refresh;
1376                         goto out_retry;
1377                 case RPC_AUTH_BADCRED:
1378                 case RPC_AUTH_BADVERF:
1379                         /* possibly garbled cred/verf? */
1380                         if (!task->tk_garb_retry)
1381                                 break;
1382                         task->tk_garb_retry--;
1383                         dprintk("RPC: %5u %s: retry garbled creds\n",
1384                                         task->tk_pid, __FUNCTION__);
1385                         task->tk_action = call_bind;
1386                         goto out_retry;
1387                 case RPC_AUTH_TOOWEAK:
1388                         printk(KERN_NOTICE "call_verify: server %s requires stronger "
1389                                "authentication.\n", task->tk_client->cl_server);
1390                         break;
1391                 default:
1392                         dprintk("RPC: %5u %s: unknown auth error: %x\n",
1393                                         task->tk_pid, __FUNCTION__, n);
1394                         error = -EIO;
1395                 }
1396                 dprintk("RPC: %5u %s: call rejected %d\n",
1397                                 task->tk_pid, __FUNCTION__, n);
1398                 goto out_err;
1399         }
1400         if (!(p = rpcauth_checkverf(task, p))) {
1401                 dprintk("RPC: %5u %s: auth check failed\n",
1402                                 task->tk_pid, __FUNCTION__);
1403                 goto out_garbage;               /* bad verifier, retry */
1404         }
1405         len = p - (__be32 *)iov->iov_base - 1;
1406         if (len < 0)
1407                 goto out_overflow;
1408         switch ((n = ntohl(*p++))) {
1409         case RPC_SUCCESS:
1410                 return p;
1411         case RPC_PROG_UNAVAIL:
1412                 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1413                                 task->tk_pid, __FUNCTION__,
1414                                 (unsigned int)task->tk_client->cl_prog,
1415                                 task->tk_client->cl_server);
1416                 error = -EPFNOSUPPORT;
1417                 goto out_err;
1418         case RPC_PROG_MISMATCH:
1419                 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1420                                 "server %s\n", task->tk_pid, __FUNCTION__,
1421                                 (unsigned int)task->tk_client->cl_prog,
1422                                 (unsigned int)task->tk_client->cl_vers,
1423                                 task->tk_client->cl_server);
1424                 error = -EPROTONOSUPPORT;
1425                 goto out_err;
1426         case RPC_PROC_UNAVAIL:
1427                 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1428                                 "version %u on server %s\n",
1429                                 task->tk_pid, __FUNCTION__,
1430                                 task->tk_msg.rpc_proc,
1431                                 task->tk_client->cl_prog,
1432                                 task->tk_client->cl_vers,
1433                                 task->tk_client->cl_server);
1434                 error = -EOPNOTSUPP;
1435                 goto out_err;
1436         case RPC_GARBAGE_ARGS:
1437                 dprintk("RPC: %5u %s: server saw garbage\n",
1438                                 task->tk_pid, __FUNCTION__);
1439                 break;                  /* retry */
1440         default:
1441                 dprintk("RPC: %5u %s: server accept status: %x\n",
1442                                 task->tk_pid, __FUNCTION__, n);
1443                 /* Also retry */
1444         }
1445
1446 out_garbage:
1447         task->tk_client->cl_stats->rpcgarbage++;
1448         if (task->tk_garb_retry) {
1449                 task->tk_garb_retry--;
1450                 dprintk("RPC: %5u %s: retrying\n",
1451                                 task->tk_pid, __FUNCTION__);
1452                 task->tk_action = call_bind;
1453 out_retry:
1454                 return ERR_PTR(-EAGAIN);
1455         }
1456 out_eio:
1457         error = -EIO;
1458 out_err:
1459         rpc_exit(task, error);
1460         dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1461                         __FUNCTION__, error);
1462         return ERR_PTR(error);
1463 out_overflow:
1464         dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1465                         __FUNCTION__);
1466         goto out_garbage;
1467 }
1468
1469 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1470 {
1471         return 0;
1472 }
1473
1474 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1475 {
1476         return 0;
1477 }
1478
1479 static struct rpc_procinfo rpcproc_null = {
1480         .p_encode = rpcproc_encode_null,
1481         .p_decode = rpcproc_decode_null,
1482 };
1483
1484 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1485 {
1486         struct rpc_message msg = {
1487                 .rpc_proc = &rpcproc_null,
1488         };
1489         int err;
1490         msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1491         err = rpc_call_sync(clnt, &msg, flags);
1492         put_rpccred(msg.rpc_cred);
1493         return err;
1494 }
1495
1496 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1497 {
1498         struct rpc_message msg = {
1499                 .rpc_proc = &rpcproc_null,
1500                 .rpc_cred = cred,
1501         };
1502         return rpc_do_run_task(clnt, &msg, flags, &rpc_default_ops, NULL);
1503 }
1504 EXPORT_SYMBOL(rpc_call_null);
1505
1506 #ifdef RPC_DEBUG
1507 void rpc_show_tasks(void)
1508 {
1509         struct rpc_clnt *clnt;
1510         struct rpc_task *t;
1511
1512         spin_lock(&rpc_client_lock);
1513         if (list_empty(&all_clients))
1514                 goto out;
1515         printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1516                 "-rpcwait -action- ---ops--\n");
1517         list_for_each_entry(clnt, &all_clients, cl_clients) {
1518                 if (list_empty(&clnt->cl_tasks))
1519                         continue;
1520                 spin_lock(&clnt->cl_lock);
1521                 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1522                         const char *rpc_waitq = "none";
1523
1524                         if (RPC_IS_QUEUED(t))
1525                                 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1526
1527                         printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1528                                 t->tk_pid,
1529                                 (t->tk_msg.rpc_proc ? t->tk_msg.rpc_proc->p_proc : -1),
1530                                 t->tk_flags, t->tk_status,
1531                                 t->tk_client,
1532                                 (t->tk_client ? t->tk_client->cl_prog : 0),
1533                                 t->tk_rqstp, t->tk_timeout,
1534                                 rpc_waitq,
1535                                 t->tk_action, t->tk_ops);
1536                 }
1537                 spin_unlock(&clnt->cl_lock);
1538         }
1539 out:
1540         spin_unlock(&rpc_client_lock);
1541 }
1542 #endif