SUNRPC: Add a helper rpc_call_start() that initialises task->tk_action
[GitHub/moto-9609/android_kernel_motorola_exynos9610.git] / 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 size_t len;
131
132 /* sanity check the name before trying to print it */
133 err = -EINVAL;
134 len = strlen(servname);
135 if (len > RPC_MAXNETNAMELEN)
136 goto out_no_rpciod;
137 len++;
138
139 dprintk("RPC: creating %s client for %s (xprt %p)\n",
140 program->name, servname, xprt);
141
142 err = rpciod_up();
143 if (err)
144 goto out_no_rpciod;
145 err = -EINVAL;
146 if (!xprt)
147 goto out_no_xprt;
148 if (vers >= program->nrvers || !(version = program->version[vers]))
149 goto out_err;
150
151 err = -ENOMEM;
152 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
153 if (!clnt)
154 goto out_err;
155 clnt->cl_parent = clnt;
156
157 clnt->cl_server = clnt->cl_inline_name;
158 if (len > sizeof(clnt->cl_inline_name)) {
159 char *buf = kmalloc(len, GFP_KERNEL);
160 if (buf != 0)
161 clnt->cl_server = buf;
162 else
163 len = sizeof(clnt->cl_inline_name);
164 }
165 strlcpy(clnt->cl_server, servname, len);
166
167 clnt->cl_xprt = xprt;
168 clnt->cl_procinfo = version->procs;
169 clnt->cl_maxproc = version->nrprocs;
170 clnt->cl_protname = program->name;
171 clnt->cl_prog = program->number;
172 clnt->cl_vers = version->number;
173 clnt->cl_stats = program->stats;
174 clnt->cl_metrics = rpc_alloc_iostats(clnt);
175 err = -ENOMEM;
176 if (clnt->cl_metrics == NULL)
177 goto out_no_stats;
178 clnt->cl_program = program;
179 INIT_LIST_HEAD(&clnt->cl_tasks);
180 spin_lock_init(&clnt->cl_lock);
181
182 if (!xprt_bound(clnt->cl_xprt))
183 clnt->cl_autobind = 1;
184
185 clnt->cl_rtt = &clnt->cl_rtt_default;
186 rpc_init_rtt(&clnt->cl_rtt_default, xprt->timeout.to_initval);
187
188 kref_init(&clnt->cl_kref);
189
190 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
191 if (err < 0)
192 goto out_no_path;
193
194 auth = rpcauth_create(flavor, clnt);
195 if (IS_ERR(auth)) {
196 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
197 flavor);
198 err = PTR_ERR(auth);
199 goto out_no_auth;
200 }
201
202 /* save the nodename */
203 clnt->cl_nodelen = strlen(utsname()->nodename);
204 if (clnt->cl_nodelen > UNX_MAXNODENAME)
205 clnt->cl_nodelen = UNX_MAXNODENAME;
206 memcpy(clnt->cl_nodename, utsname()->nodename, clnt->cl_nodelen);
207 rpc_register_client(clnt);
208 return clnt;
209
210 out_no_auth:
211 if (!IS_ERR(clnt->cl_dentry)) {
212 rpc_rmdir(clnt->cl_dentry);
213 rpc_put_mount();
214 }
215 out_no_path:
216 rpc_free_iostats(clnt->cl_metrics);
217 out_no_stats:
218 if (clnt->cl_server != clnt->cl_inline_name)
219 kfree(clnt->cl_server);
220 kfree(clnt);
221 out_err:
222 xprt_put(xprt);
223 out_no_xprt:
224 rpciod_down();
225 out_no_rpciod:
226 return ERR_PTR(err);
227 }
228
229 /*
230 * rpc_create - create an RPC client and transport with one call
231 * @args: rpc_clnt create argument structure
232 *
233 * Creates and initializes an RPC transport and an RPC client.
234 *
235 * It can ping the server in order to determine if it is up, and to see if
236 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
237 * this behavior so asynchronous tasks can also use rpc_create.
238 */
239 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
240 {
241 struct rpc_xprt *xprt;
242 struct rpc_clnt *clnt;
243 struct xprt_create xprtargs = {
244 .ident = args->protocol,
245 .srcaddr = args->saddress,
246 .dstaddr = args->address,
247 .addrlen = args->addrsize,
248 .timeout = args->timeout
249 };
250 char servername[20];
251
252 xprt = xprt_create_transport(&xprtargs);
253 if (IS_ERR(xprt))
254 return (struct rpc_clnt *)xprt;
255
256 /*
257 * If the caller chooses not to specify a hostname, whip
258 * up a string representation of the passed-in address.
259 */
260 if (args->servername == NULL) {
261 struct sockaddr_in *addr =
262 (struct sockaddr_in *) args->address;
263 snprintf(servername, sizeof(servername), NIPQUAD_FMT,
264 NIPQUAD(addr->sin_addr.s_addr));
265 args->servername = servername;
266 }
267
268 /*
269 * By default, kernel RPC client connects from a reserved port.
270 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
271 * but it is always enabled for rpciod, which handles the connect
272 * operation.
273 */
274 xprt->resvport = 1;
275 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
276 xprt->resvport = 0;
277
278 clnt = rpc_new_client(xprt, args->servername, args->program,
279 args->version, args->authflavor);
280 if (IS_ERR(clnt))
281 return clnt;
282
283 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
284 int err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
285 if (err != 0) {
286 rpc_shutdown_client(clnt);
287 return ERR_PTR(err);
288 }
289 }
290
291 clnt->cl_softrtry = 1;
292 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
293 clnt->cl_softrtry = 0;
294
295 if (args->flags & RPC_CLNT_CREATE_INTR)
296 clnt->cl_intr = 1;
297 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
298 clnt->cl_autobind = 1;
299 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
300 clnt->cl_discrtry = 1;
301
302 return clnt;
303 }
304 EXPORT_SYMBOL_GPL(rpc_create);
305
306 /*
307 * This function clones the RPC client structure. It allows us to share the
308 * same transport while varying parameters such as the authentication
309 * flavour.
310 */
311 struct rpc_clnt *
312 rpc_clone_client(struct rpc_clnt *clnt)
313 {
314 struct rpc_clnt *new;
315 int err = -ENOMEM;
316
317 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
318 if (!new)
319 goto out_no_clnt;
320 new->cl_parent = clnt;
321 /* Turn off autobind on clones */
322 new->cl_autobind = 0;
323 INIT_LIST_HEAD(&new->cl_tasks);
324 spin_lock_init(&new->cl_lock);
325 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
326 new->cl_metrics = rpc_alloc_iostats(clnt);
327 if (new->cl_metrics == NULL)
328 goto out_no_stats;
329 kref_init(&new->cl_kref);
330 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
331 if (err != 0)
332 goto out_no_path;
333 if (new->cl_auth)
334 atomic_inc(&new->cl_auth->au_count);
335 xprt_get(clnt->cl_xprt);
336 kref_get(&clnt->cl_kref);
337 rpc_register_client(new);
338 rpciod_up();
339 return new;
340 out_no_path:
341 rpc_free_iostats(new->cl_metrics);
342 out_no_stats:
343 kfree(new);
344 out_no_clnt:
345 dprintk("RPC: %s: returned error %d\n", __FUNCTION__, err);
346 return ERR_PTR(err);
347 }
348 EXPORT_SYMBOL_GPL(rpc_clone_client);
349
350 /*
351 * Properly shut down an RPC client, terminating all outstanding
352 * requests.
353 */
354 void rpc_shutdown_client(struct rpc_clnt *clnt)
355 {
356 dprintk("RPC: shutting down %s client for %s\n",
357 clnt->cl_protname, clnt->cl_server);
358
359 while (!list_empty(&clnt->cl_tasks)) {
360 rpc_killall_tasks(clnt);
361 wait_event_timeout(destroy_wait,
362 list_empty(&clnt->cl_tasks), 1*HZ);
363 }
364
365 rpc_release_client(clnt);
366 }
367 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
368
369 /*
370 * Free an RPC client
371 */
372 static void
373 rpc_free_client(struct kref *kref)
374 {
375 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
376
377 dprintk("RPC: destroying %s client for %s\n",
378 clnt->cl_protname, clnt->cl_server);
379 if (!IS_ERR(clnt->cl_dentry)) {
380 rpc_rmdir(clnt->cl_dentry);
381 rpc_put_mount();
382 }
383 if (clnt->cl_parent != clnt) {
384 rpc_release_client(clnt->cl_parent);
385 goto out_free;
386 }
387 if (clnt->cl_server != clnt->cl_inline_name)
388 kfree(clnt->cl_server);
389 out_free:
390 rpc_unregister_client(clnt);
391 rpc_free_iostats(clnt->cl_metrics);
392 clnt->cl_metrics = NULL;
393 xprt_put(clnt->cl_xprt);
394 rpciod_down();
395 kfree(clnt);
396 }
397
398 /*
399 * Free an RPC client
400 */
401 static void
402 rpc_free_auth(struct kref *kref)
403 {
404 struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
405
406 if (clnt->cl_auth == NULL) {
407 rpc_free_client(kref);
408 return;
409 }
410
411 /*
412 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
413 * release remaining GSS contexts. This mechanism ensures
414 * that it can do so safely.
415 */
416 kref_init(kref);
417 rpcauth_release(clnt->cl_auth);
418 clnt->cl_auth = NULL;
419 kref_put(kref, rpc_free_client);
420 }
421
422 /*
423 * Release reference to the RPC client
424 */
425 void
426 rpc_release_client(struct rpc_clnt *clnt)
427 {
428 dprintk("RPC: rpc_release_client(%p)\n", clnt);
429
430 if (list_empty(&clnt->cl_tasks))
431 wake_up(&destroy_wait);
432 kref_put(&clnt->cl_kref, rpc_free_auth);
433 }
434
435 /**
436 * rpc_bind_new_program - bind a new RPC program to an existing client
437 * @old - old rpc_client
438 * @program - rpc program to set
439 * @vers - rpc program version
440 *
441 * Clones the rpc client and sets up a new RPC program. This is mainly
442 * of use for enabling different RPC programs to share the same transport.
443 * The Sun NFSv2/v3 ACL protocol can do this.
444 */
445 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
446 struct rpc_program *program,
447 u32 vers)
448 {
449 struct rpc_clnt *clnt;
450 struct rpc_version *version;
451 int err;
452
453 BUG_ON(vers >= program->nrvers || !program->version[vers]);
454 version = program->version[vers];
455 clnt = rpc_clone_client(old);
456 if (IS_ERR(clnt))
457 goto out;
458 clnt->cl_procinfo = version->procs;
459 clnt->cl_maxproc = version->nrprocs;
460 clnt->cl_protname = program->name;
461 clnt->cl_prog = program->number;
462 clnt->cl_vers = version->number;
463 clnt->cl_stats = program->stats;
464 err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR);
465 if (err != 0) {
466 rpc_shutdown_client(clnt);
467 clnt = ERR_PTR(err);
468 }
469 out:
470 return clnt;
471 }
472 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
473
474 /*
475 * Default callback for async RPC calls
476 */
477 static void
478 rpc_default_callback(struct rpc_task *task, void *data)
479 {
480 }
481
482 static const struct rpc_call_ops rpc_default_ops = {
483 .rpc_call_done = rpc_default_callback,
484 };
485
486 /*
487 * Export the signal mask handling for synchronous code that
488 * sleeps on RPC calls
489 */
490 #define RPC_INTR_SIGNALS (sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT) | sigmask(SIGTERM))
491
492 static void rpc_save_sigmask(sigset_t *oldset, int intr)
493 {
494 unsigned long sigallow = sigmask(SIGKILL);
495 sigset_t sigmask;
496
497 /* Block all signals except those listed in sigallow */
498 if (intr)
499 sigallow |= RPC_INTR_SIGNALS;
500 siginitsetinv(&sigmask, sigallow);
501 sigprocmask(SIG_BLOCK, &sigmask, oldset);
502 }
503
504 static void rpc_task_sigmask(struct rpc_task *task, sigset_t *oldset)
505 {
506 rpc_save_sigmask(oldset, !RPC_TASK_UNINTERRUPTIBLE(task));
507 }
508
509 static void rpc_restore_sigmask(sigset_t *oldset)
510 {
511 sigprocmask(SIG_SETMASK, oldset, NULL);
512 }
513
514 void rpc_clnt_sigmask(struct rpc_clnt *clnt, sigset_t *oldset)
515 {
516 rpc_save_sigmask(oldset, clnt->cl_intr);
517 }
518 EXPORT_SYMBOL_GPL(rpc_clnt_sigmask);
519
520 void rpc_clnt_sigunmask(struct rpc_clnt *clnt, sigset_t *oldset)
521 {
522 rpc_restore_sigmask(oldset);
523 }
524 EXPORT_SYMBOL_GPL(rpc_clnt_sigunmask);
525
526 /**
527 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
528 * @task_setup_data: pointer to task initialisation data
529 */
530 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
531 {
532 struct rpc_task *task, *ret;
533 sigset_t oldset;
534
535 task = rpc_new_task(task_setup_data);
536 if (task == NULL) {
537 rpc_release_calldata(task_setup_data->callback_ops,
538 task_setup_data->callback_data);
539 ret = ERR_PTR(-ENOMEM);
540 goto out;
541 }
542
543 if (task_setup_data->rpc_message != NULL) {
544 rpc_call_setup(task, task_setup_data->rpc_message, 0);
545 if (task->tk_status != 0) {
546 ret = ERR_PTR(task->tk_status);
547 rpc_put_task(task);
548 goto out;
549 }
550 }
551 atomic_inc(&task->tk_count);
552 /* Mask signals on synchronous RPC calls and RPCSEC_GSS upcalls */
553 rpc_task_sigmask(task, &oldset);
554 rpc_execute(task);
555 rpc_restore_sigmask(&oldset);
556 ret = task;
557 out:
558 return ret;
559 }
560 EXPORT_SYMBOL_GPL(rpc_run_task);
561
562 /**
563 * rpc_call_sync - Perform a synchronous RPC call
564 * @clnt: pointer to RPC client
565 * @msg: RPC call parameters
566 * @flags: RPC call flags
567 */
568 int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
569 {
570 struct rpc_task *task;
571 struct rpc_task_setup task_setup_data = {
572 .rpc_client = clnt,
573 .rpc_message = msg,
574 .callback_ops = &rpc_default_ops,
575 .flags = flags,
576 };
577 int status;
578
579 BUG_ON(flags & RPC_TASK_ASYNC);
580
581 task = rpc_run_task(&task_setup_data);
582 if (IS_ERR(task))
583 return PTR_ERR(task);
584 status = task->tk_status;
585 rpc_put_task(task);
586 return status;
587 }
588 EXPORT_SYMBOL_GPL(rpc_call_sync);
589
590 /**
591 * rpc_call_async - Perform an asynchronous RPC call
592 * @clnt: pointer to RPC client
593 * @msg: RPC call parameters
594 * @flags: RPC call flags
595 * @ops: RPC call ops
596 * @data: user call data
597 */
598 int
599 rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
600 const struct rpc_call_ops *tk_ops, void *data)
601 {
602 struct rpc_task *task;
603 struct rpc_task_setup task_setup_data = {
604 .rpc_client = clnt,
605 .rpc_message = msg,
606 .callback_ops = tk_ops,
607 .callback_data = data,
608 .flags = flags|RPC_TASK_ASYNC,
609 };
610
611 task = rpc_run_task(&task_setup_data);
612 if (IS_ERR(task))
613 return PTR_ERR(task);
614 rpc_put_task(task);
615 return 0;
616 }
617 EXPORT_SYMBOL_GPL(rpc_call_async);
618
619 void
620 rpc_call_setup(struct rpc_task *task, const struct rpc_message *msg, int flags)
621 {
622 task->tk_msg = *msg;
623 task->tk_flags |= flags;
624 /* Bind the user cred */
625 if (task->tk_msg.rpc_cred != NULL)
626 rpcauth_holdcred(task);
627 else
628 rpcauth_bindcred(task);
629
630 if (task->tk_status == 0)
631 task->tk_action = call_start;
632 else
633 task->tk_action = rpc_exit_task;
634 }
635 EXPORT_SYMBOL_GPL(rpc_call_setup);
636
637 void
638 rpc_call_start(struct rpc_task *task)
639 {
640 task->tk_action = call_start;
641 }
642 EXPORT_SYMBOL_GPL(rpc_call_start);
643
644 /**
645 * rpc_peeraddr - extract remote peer address from clnt's xprt
646 * @clnt: RPC client structure
647 * @buf: target buffer
648 * @size: length of target buffer
649 *
650 * Returns the number of bytes that are actually in the stored address.
651 */
652 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
653 {
654 size_t bytes;
655 struct rpc_xprt *xprt = clnt->cl_xprt;
656
657 bytes = sizeof(xprt->addr);
658 if (bytes > bufsize)
659 bytes = bufsize;
660 memcpy(buf, &clnt->cl_xprt->addr, bytes);
661 return xprt->addrlen;
662 }
663 EXPORT_SYMBOL_GPL(rpc_peeraddr);
664
665 /**
666 * rpc_peeraddr2str - return remote peer address in printable format
667 * @clnt: RPC client structure
668 * @format: address format
669 *
670 */
671 char *rpc_peeraddr2str(struct rpc_clnt *clnt, enum rpc_display_format_t format)
672 {
673 struct rpc_xprt *xprt = clnt->cl_xprt;
674
675 if (xprt->address_strings[format] != NULL)
676 return xprt->address_strings[format];
677 else
678 return "unprintable";
679 }
680 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
681
682 void
683 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
684 {
685 struct rpc_xprt *xprt = clnt->cl_xprt;
686 if (xprt->ops->set_buffer_size)
687 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
688 }
689 EXPORT_SYMBOL_GPL(rpc_setbufsize);
690
691 /*
692 * Return size of largest payload RPC client can support, in bytes
693 *
694 * For stream transports, this is one RPC record fragment (see RFC
695 * 1831), as we don't support multi-record requests yet. For datagram
696 * transports, this is the size of an IP packet minus the IP, UDP, and
697 * RPC header sizes.
698 */
699 size_t rpc_max_payload(struct rpc_clnt *clnt)
700 {
701 return clnt->cl_xprt->max_payload;
702 }
703 EXPORT_SYMBOL_GPL(rpc_max_payload);
704
705 /**
706 * rpc_force_rebind - force transport to check that remote port is unchanged
707 * @clnt: client to rebind
708 *
709 */
710 void rpc_force_rebind(struct rpc_clnt *clnt)
711 {
712 if (clnt->cl_autobind)
713 xprt_clear_bound(clnt->cl_xprt);
714 }
715 EXPORT_SYMBOL_GPL(rpc_force_rebind);
716
717 /*
718 * Restart an (async) RPC call. Usually called from within the
719 * exit handler.
720 */
721 void
722 rpc_restart_call(struct rpc_task *task)
723 {
724 if (RPC_ASSASSINATED(task))
725 return;
726
727 task->tk_action = call_start;
728 }
729 EXPORT_SYMBOL_GPL(rpc_restart_call);
730
731 /*
732 * 0. Initial state
733 *
734 * Other FSM states can be visited zero or more times, but
735 * this state is visited exactly once for each RPC.
736 */
737 static void
738 call_start(struct rpc_task *task)
739 {
740 struct rpc_clnt *clnt = task->tk_client;
741
742 dprintk("RPC: %5u call_start %s%d proc %d (%s)\n", task->tk_pid,
743 clnt->cl_protname, clnt->cl_vers,
744 task->tk_msg.rpc_proc->p_proc,
745 (RPC_IS_ASYNC(task) ? "async" : "sync"));
746
747 /* Increment call count */
748 task->tk_msg.rpc_proc->p_count++;
749 clnt->cl_stats->rpccnt++;
750 task->tk_action = call_reserve;
751 }
752
753 /*
754 * 1. Reserve an RPC call slot
755 */
756 static void
757 call_reserve(struct rpc_task *task)
758 {
759 dprint_status(task);
760
761 if (!rpcauth_uptodatecred(task)) {
762 task->tk_action = call_refresh;
763 return;
764 }
765
766 task->tk_status = 0;
767 task->tk_action = call_reserveresult;
768 xprt_reserve(task);
769 }
770
771 /*
772 * 1b. Grok the result of xprt_reserve()
773 */
774 static void
775 call_reserveresult(struct rpc_task *task)
776 {
777 int status = task->tk_status;
778
779 dprint_status(task);
780
781 /*
782 * After a call to xprt_reserve(), we must have either
783 * a request slot or else an error status.
784 */
785 task->tk_status = 0;
786 if (status >= 0) {
787 if (task->tk_rqstp) {
788 task->tk_action = call_allocate;
789 return;
790 }
791
792 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
793 __FUNCTION__, status);
794 rpc_exit(task, -EIO);
795 return;
796 }
797
798 /*
799 * Even though there was an error, we may have acquired
800 * a request slot somehow. Make sure not to leak it.
801 */
802 if (task->tk_rqstp) {
803 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
804 __FUNCTION__, status);
805 xprt_release(task);
806 }
807
808 switch (status) {
809 case -EAGAIN: /* woken up; retry */
810 task->tk_action = call_reserve;
811 return;
812 case -EIO: /* probably a shutdown */
813 break;
814 default:
815 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
816 __FUNCTION__, status);
817 break;
818 }
819 rpc_exit(task, status);
820 }
821
822 /*
823 * 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
824 * (Note: buffer memory is freed in xprt_release).
825 */
826 static void
827 call_allocate(struct rpc_task *task)
828 {
829 unsigned int slack = task->tk_msg.rpc_cred->cr_auth->au_cslack;
830 struct rpc_rqst *req = task->tk_rqstp;
831 struct rpc_xprt *xprt = task->tk_xprt;
832 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
833
834 dprint_status(task);
835
836 task->tk_status = 0;
837 task->tk_action = call_bind;
838
839 if (req->rq_buffer)
840 return;
841
842 if (proc->p_proc != 0) {
843 BUG_ON(proc->p_arglen == 0);
844 if (proc->p_decode != NULL)
845 BUG_ON(proc->p_replen == 0);
846 }
847
848 /*
849 * Calculate the size (in quads) of the RPC call
850 * and reply headers, and convert both values
851 * to byte sizes.
852 */
853 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
854 req->rq_callsize <<= 2;
855 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
856 req->rq_rcvsize <<= 2;
857
858 req->rq_buffer = xprt->ops->buf_alloc(task,
859 req->rq_callsize + req->rq_rcvsize);
860 if (req->rq_buffer != NULL)
861 return;
862
863 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
864
865 if (RPC_IS_ASYNC(task) || !signalled()) {
866 task->tk_action = call_allocate;
867 rpc_delay(task, HZ>>4);
868 return;
869 }
870
871 rpc_exit(task, -ERESTARTSYS);
872 }
873
874 static inline int
875 rpc_task_need_encode(struct rpc_task *task)
876 {
877 return task->tk_rqstp->rq_snd_buf.len == 0;
878 }
879
880 static inline void
881 rpc_task_force_reencode(struct rpc_task *task)
882 {
883 task->tk_rqstp->rq_snd_buf.len = 0;
884 }
885
886 static inline void
887 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
888 {
889 buf->head[0].iov_base = start;
890 buf->head[0].iov_len = len;
891 buf->tail[0].iov_len = 0;
892 buf->page_len = 0;
893 buf->flags = 0;
894 buf->len = 0;
895 buf->buflen = len;
896 }
897
898 /*
899 * 3. Encode arguments of an RPC call
900 */
901 static void
902 call_encode(struct rpc_task *task)
903 {
904 struct rpc_rqst *req = task->tk_rqstp;
905 kxdrproc_t encode;
906 __be32 *p;
907
908 dprint_status(task);
909
910 rpc_xdr_buf_init(&req->rq_snd_buf,
911 req->rq_buffer,
912 req->rq_callsize);
913 rpc_xdr_buf_init(&req->rq_rcv_buf,
914 (char *)req->rq_buffer + req->rq_callsize,
915 req->rq_rcvsize);
916
917 /* Encode header and provided arguments */
918 encode = task->tk_msg.rpc_proc->p_encode;
919 if (!(p = call_header(task))) {
920 printk(KERN_INFO "RPC: call_header failed, exit EIO\n");
921 rpc_exit(task, -EIO);
922 return;
923 }
924 if (encode == NULL)
925 return;
926
927 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
928 task->tk_msg.rpc_argp);
929 if (task->tk_status == -ENOMEM) {
930 /* XXX: Is this sane? */
931 rpc_delay(task, 3*HZ);
932 task->tk_status = -EAGAIN;
933 }
934 }
935
936 /*
937 * 4. Get the server port number if not yet set
938 */
939 static void
940 call_bind(struct rpc_task *task)
941 {
942 struct rpc_xprt *xprt = task->tk_xprt;
943
944 dprint_status(task);
945
946 task->tk_action = call_connect;
947 if (!xprt_bound(xprt)) {
948 task->tk_action = call_bind_status;
949 task->tk_timeout = xprt->bind_timeout;
950 xprt->ops->rpcbind(task);
951 }
952 }
953
954 /*
955 * 4a. Sort out bind result
956 */
957 static void
958 call_bind_status(struct rpc_task *task)
959 {
960 int status = -EIO;
961
962 if (task->tk_status >= 0) {
963 dprint_status(task);
964 task->tk_status = 0;
965 task->tk_action = call_connect;
966 return;
967 }
968
969 switch (task->tk_status) {
970 case -EAGAIN:
971 dprintk("RPC: %5u rpcbind waiting for another request "
972 "to finish\n", task->tk_pid);
973 /* avoid busy-waiting here -- could be a network outage. */
974 rpc_delay(task, 5*HZ);
975 goto retry_timeout;
976 case -EACCES:
977 dprintk("RPC: %5u remote rpcbind: RPC program/version "
978 "unavailable\n", task->tk_pid);
979 /* fail immediately if this is an RPC ping */
980 if (task->tk_msg.rpc_proc->p_proc == 0) {
981 status = -EOPNOTSUPP;
982 break;
983 }
984 rpc_delay(task, 3*HZ);
985 goto retry_timeout;
986 case -ETIMEDOUT:
987 dprintk("RPC: %5u rpcbind request timed out\n",
988 task->tk_pid);
989 goto retry_timeout;
990 case -EPFNOSUPPORT:
991 /* server doesn't support any rpcbind version we know of */
992 dprintk("RPC: %5u remote rpcbind service unavailable\n",
993 task->tk_pid);
994 break;
995 case -EPROTONOSUPPORT:
996 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
997 task->tk_pid);
998 task->tk_status = 0;
999 task->tk_action = call_bind;
1000 return;
1001 default:
1002 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1003 task->tk_pid, -task->tk_status);
1004 }
1005
1006 rpc_exit(task, status);
1007 return;
1008
1009 retry_timeout:
1010 task->tk_action = call_timeout;
1011 }
1012
1013 /*
1014 * 4b. Connect to the RPC server
1015 */
1016 static void
1017 call_connect(struct rpc_task *task)
1018 {
1019 struct rpc_xprt *xprt = task->tk_xprt;
1020
1021 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1022 task->tk_pid, xprt,
1023 (xprt_connected(xprt) ? "is" : "is not"));
1024
1025 task->tk_action = call_transmit;
1026 if (!xprt_connected(xprt)) {
1027 task->tk_action = call_connect_status;
1028 if (task->tk_status < 0)
1029 return;
1030 xprt_connect(task);
1031 }
1032 }
1033
1034 /*
1035 * 4c. Sort out connect result
1036 */
1037 static void
1038 call_connect_status(struct rpc_task *task)
1039 {
1040 struct rpc_clnt *clnt = task->tk_client;
1041 int status = task->tk_status;
1042
1043 dprint_status(task);
1044
1045 task->tk_status = 0;
1046 if (status >= 0) {
1047 clnt->cl_stats->netreconn++;
1048 task->tk_action = call_transmit;
1049 return;
1050 }
1051
1052 /* Something failed: remote service port may have changed */
1053 rpc_force_rebind(clnt);
1054
1055 switch (status) {
1056 case -ENOTCONN:
1057 case -EAGAIN:
1058 task->tk_action = call_bind;
1059 if (!RPC_IS_SOFT(task))
1060 return;
1061 /* if soft mounted, test if we've timed out */
1062 case -ETIMEDOUT:
1063 task->tk_action = call_timeout;
1064 return;
1065 }
1066 rpc_exit(task, -EIO);
1067 }
1068
1069 /*
1070 * 5. Transmit the RPC request, and wait for reply
1071 */
1072 static void
1073 call_transmit(struct rpc_task *task)
1074 {
1075 dprint_status(task);
1076
1077 task->tk_action = call_status;
1078 if (task->tk_status < 0)
1079 return;
1080 task->tk_status = xprt_prepare_transmit(task);
1081 if (task->tk_status != 0)
1082 return;
1083 task->tk_action = call_transmit_status;
1084 /* Encode here so that rpcsec_gss can use correct sequence number. */
1085 if (rpc_task_need_encode(task)) {
1086 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1087 call_encode(task);
1088 /* Did the encode result in an error condition? */
1089 if (task->tk_status != 0)
1090 return;
1091 }
1092 xprt_transmit(task);
1093 if (task->tk_status < 0)
1094 return;
1095 /*
1096 * On success, ensure that we call xprt_end_transmit() before sleeping
1097 * in order to allow access to the socket to other RPC requests.
1098 */
1099 call_transmit_status(task);
1100 if (task->tk_msg.rpc_proc->p_decode != NULL)
1101 return;
1102 task->tk_action = rpc_exit_task;
1103 rpc_wake_up_task(task);
1104 }
1105
1106 /*
1107 * 5a. Handle cleanup after a transmission
1108 */
1109 static void
1110 call_transmit_status(struct rpc_task *task)
1111 {
1112 task->tk_action = call_status;
1113 /*
1114 * Special case: if we've been waiting on the socket's write_space()
1115 * callback, then don't call xprt_end_transmit().
1116 */
1117 if (task->tk_status == -EAGAIN)
1118 return;
1119 xprt_end_transmit(task);
1120 rpc_task_force_reencode(task);
1121 }
1122
1123 /*
1124 * 6. Sort out the RPC call status
1125 */
1126 static void
1127 call_status(struct rpc_task *task)
1128 {
1129 struct rpc_clnt *clnt = task->tk_client;
1130 struct rpc_rqst *req = task->tk_rqstp;
1131 int status;
1132
1133 if (req->rq_received > 0 && !req->rq_bytes_sent)
1134 task->tk_status = req->rq_received;
1135
1136 dprint_status(task);
1137
1138 status = task->tk_status;
1139 if (status >= 0) {
1140 task->tk_action = call_decode;
1141 return;
1142 }
1143
1144 task->tk_status = 0;
1145 switch(status) {
1146 case -EHOSTDOWN:
1147 case -EHOSTUNREACH:
1148 case -ENETUNREACH:
1149 /*
1150 * Delay any retries for 3 seconds, then handle as if it
1151 * were a timeout.
1152 */
1153 rpc_delay(task, 3*HZ);
1154 case -ETIMEDOUT:
1155 task->tk_action = call_timeout;
1156 if (task->tk_client->cl_discrtry)
1157 xprt_force_disconnect(task->tk_xprt);
1158 break;
1159 case -ECONNREFUSED:
1160 case -ENOTCONN:
1161 rpc_force_rebind(clnt);
1162 task->tk_action = call_bind;
1163 break;
1164 case -EAGAIN:
1165 task->tk_action = call_transmit;
1166 break;
1167 case -EIO:
1168 /* shutdown or soft timeout */
1169 rpc_exit(task, status);
1170 break;
1171 default:
1172 printk("%s: RPC call returned error %d\n",
1173 clnt->cl_protname, -status);
1174 rpc_exit(task, status);
1175 }
1176 }
1177
1178 /*
1179 * 6a. Handle RPC timeout
1180 * We do not release the request slot, so we keep using the
1181 * same XID for all retransmits.
1182 */
1183 static void
1184 call_timeout(struct rpc_task *task)
1185 {
1186 struct rpc_clnt *clnt = task->tk_client;
1187
1188 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1189 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1190 goto retry;
1191 }
1192
1193 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1194 task->tk_timeouts++;
1195
1196 if (RPC_IS_SOFT(task)) {
1197 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1198 clnt->cl_protname, clnt->cl_server);
1199 rpc_exit(task, -EIO);
1200 return;
1201 }
1202
1203 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1204 task->tk_flags |= RPC_CALL_MAJORSEEN;
1205 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1206 clnt->cl_protname, clnt->cl_server);
1207 }
1208 rpc_force_rebind(clnt);
1209
1210 retry:
1211 clnt->cl_stats->rpcretrans++;
1212 task->tk_action = call_bind;
1213 task->tk_status = 0;
1214 }
1215
1216 /*
1217 * 7. Decode the RPC reply
1218 */
1219 static void
1220 call_decode(struct rpc_task *task)
1221 {
1222 struct rpc_clnt *clnt = task->tk_client;
1223 struct rpc_rqst *req = task->tk_rqstp;
1224 kxdrproc_t decode = task->tk_msg.rpc_proc->p_decode;
1225 __be32 *p;
1226
1227 dprintk("RPC: %5u call_decode (status %d)\n",
1228 task->tk_pid, task->tk_status);
1229
1230 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1231 printk(KERN_NOTICE "%s: server %s OK\n",
1232 clnt->cl_protname, clnt->cl_server);
1233 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1234 }
1235
1236 if (task->tk_status < 12) {
1237 if (!RPC_IS_SOFT(task)) {
1238 task->tk_action = call_bind;
1239 clnt->cl_stats->rpcretrans++;
1240 goto out_retry;
1241 }
1242 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1243 clnt->cl_protname, task->tk_status);
1244 task->tk_action = call_timeout;
1245 goto out_retry;
1246 }
1247
1248 /*
1249 * Ensure that we see all writes made by xprt_complete_rqst()
1250 * before it changed req->rq_received.
1251 */
1252 smp_rmb();
1253 req->rq_rcv_buf.len = req->rq_private_buf.len;
1254
1255 /* Check that the softirq receive buffer is valid */
1256 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1257 sizeof(req->rq_rcv_buf)) != 0);
1258
1259 /* Verify the RPC header */
1260 p = call_verify(task);
1261 if (IS_ERR(p)) {
1262 if (p == ERR_PTR(-EAGAIN))
1263 goto out_retry;
1264 return;
1265 }
1266
1267 task->tk_action = rpc_exit_task;
1268
1269 if (decode) {
1270 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1271 task->tk_msg.rpc_resp);
1272 }
1273 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1274 task->tk_status);
1275 return;
1276 out_retry:
1277 req->rq_received = req->rq_private_buf.len = 0;
1278 task->tk_status = 0;
1279 if (task->tk_client->cl_discrtry)
1280 xprt_force_disconnect(task->tk_xprt);
1281 }
1282
1283 /*
1284 * 8. Refresh the credentials if rejected by the server
1285 */
1286 static void
1287 call_refresh(struct rpc_task *task)
1288 {
1289 dprint_status(task);
1290
1291 task->tk_action = call_refreshresult;
1292 task->tk_status = 0;
1293 task->tk_client->cl_stats->rpcauthrefresh++;
1294 rpcauth_refreshcred(task);
1295 }
1296
1297 /*
1298 * 8a. Process the results of a credential refresh
1299 */
1300 static void
1301 call_refreshresult(struct rpc_task *task)
1302 {
1303 int status = task->tk_status;
1304
1305 dprint_status(task);
1306
1307 task->tk_status = 0;
1308 task->tk_action = call_reserve;
1309 if (status >= 0 && rpcauth_uptodatecred(task))
1310 return;
1311 if (status == -EACCES) {
1312 rpc_exit(task, -EACCES);
1313 return;
1314 }
1315 task->tk_action = call_refresh;
1316 if (status != -ETIMEDOUT)
1317 rpc_delay(task, 3*HZ);
1318 return;
1319 }
1320
1321 /*
1322 * Call header serialization
1323 */
1324 static __be32 *
1325 call_header(struct rpc_task *task)
1326 {
1327 struct rpc_clnt *clnt = task->tk_client;
1328 struct rpc_rqst *req = task->tk_rqstp;
1329 __be32 *p = req->rq_svec[0].iov_base;
1330
1331 /* FIXME: check buffer size? */
1332
1333 p = xprt_skip_transport_header(task->tk_xprt, p);
1334 *p++ = req->rq_xid; /* XID */
1335 *p++ = htonl(RPC_CALL); /* CALL */
1336 *p++ = htonl(RPC_VERSION); /* RPC version */
1337 *p++ = htonl(clnt->cl_prog); /* program number */
1338 *p++ = htonl(clnt->cl_vers); /* program version */
1339 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1340 p = rpcauth_marshcred(task, p);
1341 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1342 return p;
1343 }
1344
1345 /*
1346 * Reply header verification
1347 */
1348 static __be32 *
1349 call_verify(struct rpc_task *task)
1350 {
1351 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1352 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1353 __be32 *p = iov->iov_base;
1354 u32 n;
1355 int error = -EACCES;
1356
1357 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1358 /* RFC-1014 says that the representation of XDR data must be a
1359 * multiple of four bytes
1360 * - if it isn't pointer subtraction in the NFS client may give
1361 * undefined results
1362 */
1363 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1364 " 4 bytes: 0x%x\n", task->tk_pid, __FUNCTION__,
1365 task->tk_rqstp->rq_rcv_buf.len);
1366 goto out_eio;
1367 }
1368 if ((len -= 3) < 0)
1369 goto out_overflow;
1370 p += 1; /* skip XID */
1371
1372 if ((n = ntohl(*p++)) != RPC_REPLY) {
1373 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1374 task->tk_pid, __FUNCTION__, n);
1375 goto out_garbage;
1376 }
1377 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1378 if (--len < 0)
1379 goto out_overflow;
1380 switch ((n = ntohl(*p++))) {
1381 case RPC_AUTH_ERROR:
1382 break;
1383 case RPC_MISMATCH:
1384 dprintk("RPC: %5u %s: RPC call version "
1385 "mismatch!\n",
1386 task->tk_pid, __FUNCTION__);
1387 error = -EPROTONOSUPPORT;
1388 goto out_err;
1389 default:
1390 dprintk("RPC: %5u %s: RPC call rejected, "
1391 "unknown error: %x\n",
1392 task->tk_pid, __FUNCTION__, n);
1393 goto out_eio;
1394 }
1395 if (--len < 0)
1396 goto out_overflow;
1397 switch ((n = ntohl(*p++))) {
1398 case RPC_AUTH_REJECTEDCRED:
1399 case RPC_AUTH_REJECTEDVERF:
1400 case RPCSEC_GSS_CREDPROBLEM:
1401 case RPCSEC_GSS_CTXPROBLEM:
1402 if (!task->tk_cred_retry)
1403 break;
1404 task->tk_cred_retry--;
1405 dprintk("RPC: %5u %s: retry stale creds\n",
1406 task->tk_pid, __FUNCTION__);
1407 rpcauth_invalcred(task);
1408 /* Ensure we obtain a new XID! */
1409 xprt_release(task);
1410 task->tk_action = call_refresh;
1411 goto out_retry;
1412 case RPC_AUTH_BADCRED:
1413 case RPC_AUTH_BADVERF:
1414 /* possibly garbled cred/verf? */
1415 if (!task->tk_garb_retry)
1416 break;
1417 task->tk_garb_retry--;
1418 dprintk("RPC: %5u %s: retry garbled creds\n",
1419 task->tk_pid, __FUNCTION__);
1420 task->tk_action = call_bind;
1421 goto out_retry;
1422 case RPC_AUTH_TOOWEAK:
1423 printk(KERN_NOTICE "call_verify: server %s requires stronger "
1424 "authentication.\n", task->tk_client->cl_server);
1425 break;
1426 default:
1427 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1428 task->tk_pid, __FUNCTION__, n);
1429 error = -EIO;
1430 }
1431 dprintk("RPC: %5u %s: call rejected %d\n",
1432 task->tk_pid, __FUNCTION__, n);
1433 goto out_err;
1434 }
1435 if (!(p = rpcauth_checkverf(task, p))) {
1436 dprintk("RPC: %5u %s: auth check failed\n",
1437 task->tk_pid, __FUNCTION__);
1438 goto out_garbage; /* bad verifier, retry */
1439 }
1440 len = p - (__be32 *)iov->iov_base - 1;
1441 if (len < 0)
1442 goto out_overflow;
1443 switch ((n = ntohl(*p++))) {
1444 case RPC_SUCCESS:
1445 return p;
1446 case RPC_PROG_UNAVAIL:
1447 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1448 task->tk_pid, __FUNCTION__,
1449 (unsigned int)task->tk_client->cl_prog,
1450 task->tk_client->cl_server);
1451 error = -EPFNOSUPPORT;
1452 goto out_err;
1453 case RPC_PROG_MISMATCH:
1454 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1455 "server %s\n", task->tk_pid, __FUNCTION__,
1456 (unsigned int)task->tk_client->cl_prog,
1457 (unsigned int)task->tk_client->cl_vers,
1458 task->tk_client->cl_server);
1459 error = -EPROTONOSUPPORT;
1460 goto out_err;
1461 case RPC_PROC_UNAVAIL:
1462 dprintk("RPC: %5u %s: proc %p unsupported by program %u, "
1463 "version %u on server %s\n",
1464 task->tk_pid, __FUNCTION__,
1465 task->tk_msg.rpc_proc,
1466 task->tk_client->cl_prog,
1467 task->tk_client->cl_vers,
1468 task->tk_client->cl_server);
1469 error = -EOPNOTSUPP;
1470 goto out_err;
1471 case RPC_GARBAGE_ARGS:
1472 dprintk("RPC: %5u %s: server saw garbage\n",
1473 task->tk_pid, __FUNCTION__);
1474 break; /* retry */
1475 default:
1476 dprintk("RPC: %5u %s: server accept status: %x\n",
1477 task->tk_pid, __FUNCTION__, n);
1478 /* Also retry */
1479 }
1480
1481 out_garbage:
1482 task->tk_client->cl_stats->rpcgarbage++;
1483 if (task->tk_garb_retry) {
1484 task->tk_garb_retry--;
1485 dprintk("RPC: %5u %s: retrying\n",
1486 task->tk_pid, __FUNCTION__);
1487 task->tk_action = call_bind;
1488 out_retry:
1489 return ERR_PTR(-EAGAIN);
1490 }
1491 out_eio:
1492 error = -EIO;
1493 out_err:
1494 rpc_exit(task, error);
1495 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1496 __FUNCTION__, error);
1497 return ERR_PTR(error);
1498 out_overflow:
1499 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1500 __FUNCTION__);
1501 goto out_garbage;
1502 }
1503
1504 static int rpcproc_encode_null(void *rqstp, __be32 *data, void *obj)
1505 {
1506 return 0;
1507 }
1508
1509 static int rpcproc_decode_null(void *rqstp, __be32 *data, void *obj)
1510 {
1511 return 0;
1512 }
1513
1514 static struct rpc_procinfo rpcproc_null = {
1515 .p_encode = rpcproc_encode_null,
1516 .p_decode = rpcproc_decode_null,
1517 };
1518
1519 static int rpc_ping(struct rpc_clnt *clnt, int flags)
1520 {
1521 struct rpc_message msg = {
1522 .rpc_proc = &rpcproc_null,
1523 };
1524 int err;
1525 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1526 err = rpc_call_sync(clnt, &msg, flags);
1527 put_rpccred(msg.rpc_cred);
1528 return err;
1529 }
1530
1531 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1532 {
1533 struct rpc_message msg = {
1534 .rpc_proc = &rpcproc_null,
1535 .rpc_cred = cred,
1536 };
1537 struct rpc_task_setup task_setup_data = {
1538 .rpc_client = clnt,
1539 .rpc_message = &msg,
1540 .callback_ops = &rpc_default_ops,
1541 .flags = flags,
1542 };
1543 return rpc_run_task(&task_setup_data);
1544 }
1545 EXPORT_SYMBOL_GPL(rpc_call_null);
1546
1547 #ifdef RPC_DEBUG
1548 void rpc_show_tasks(void)
1549 {
1550 struct rpc_clnt *clnt;
1551 struct rpc_task *t;
1552
1553 spin_lock(&rpc_client_lock);
1554 if (list_empty(&all_clients))
1555 goto out;
1556 printk("-pid- proc flgs status -client- -prog- --rqstp- -timeout "
1557 "-rpcwait -action- ---ops--\n");
1558 list_for_each_entry(clnt, &all_clients, cl_clients) {
1559 if (list_empty(&clnt->cl_tasks))
1560 continue;
1561 spin_lock(&clnt->cl_lock);
1562 list_for_each_entry(t, &clnt->cl_tasks, tk_task) {
1563 const char *rpc_waitq = "none";
1564 int proc;
1565
1566 if (t->tk_msg.rpc_proc)
1567 proc = t->tk_msg.rpc_proc->p_proc;
1568 else
1569 proc = -1;
1570
1571 if (RPC_IS_QUEUED(t))
1572 rpc_waitq = rpc_qname(t->u.tk_wait.rpc_waitq);
1573
1574 printk("%5u %04d %04x %6d %8p %6d %8p %8ld %8s %8p %8p\n",
1575 t->tk_pid, proc,
1576 t->tk_flags, t->tk_status,
1577 t->tk_client,
1578 (t->tk_client ? t->tk_client->cl_prog : 0),
1579 t->tk_rqstp, t->tk_timeout,
1580 rpc_waitq,
1581 t->tk_action, t->tk_ops);
1582 }
1583 spin_unlock(&clnt->cl_lock);
1584 }
1585 out:
1586 spin_unlock(&rpc_client_lock);
1587 }
1588 #endif