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Merge branch 'drbd-8.4_ed6' into for-3.8-drivers-drbd-8.4_ed6
[deliverable/linux.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 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
18 */
19
20
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/kallsyms.h>
24 #include <linux/mm.h>
25 #include <linux/namei.h>
26 #include <linux/mount.h>
27 #include <linux/slab.h>
28 #include <linux/utsname.h>
29 #include <linux/workqueue.h>
30 #include <linux/in.h>
31 #include <linux/in6.h>
32 #include <linux/un.h>
33 #include <linux/rcupdate.h>
34
35 #include <linux/sunrpc/clnt.h>
36 #include <linux/sunrpc/rpc_pipe_fs.h>
37 #include <linux/sunrpc/metrics.h>
38 #include <linux/sunrpc/bc_xprt.h>
39 #include <trace/events/sunrpc.h>
40
41 #include "sunrpc.h"
42 #include "netns.h"
43
44 #ifdef RPC_DEBUG
45 # define RPCDBG_FACILITY RPCDBG_CALL
46 #endif
47
48 #define dprint_status(t) \
49 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
50 __func__, t->tk_status)
51
52 /*
53 * All RPC clients are linked into this list
54 */
55
56 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
57
58
59 static void call_start(struct rpc_task *task);
60 static void call_reserve(struct rpc_task *task);
61 static void call_reserveresult(struct rpc_task *task);
62 static void call_allocate(struct rpc_task *task);
63 static void call_decode(struct rpc_task *task);
64 static void call_bind(struct rpc_task *task);
65 static void call_bind_status(struct rpc_task *task);
66 static void call_transmit(struct rpc_task *task);
67 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
68 static void call_bc_transmit(struct rpc_task *task);
69 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
70 static void call_status(struct rpc_task *task);
71 static void call_transmit_status(struct rpc_task *task);
72 static void call_refresh(struct rpc_task *task);
73 static void call_refreshresult(struct rpc_task *task);
74 static void call_timeout(struct rpc_task *task);
75 static void call_connect(struct rpc_task *task);
76 static void call_connect_status(struct rpc_task *task);
77
78 static __be32 *rpc_encode_header(struct rpc_task *task);
79 static __be32 *rpc_verify_header(struct rpc_task *task);
80 static int rpc_ping(struct rpc_clnt *clnt);
81
82 static void rpc_register_client(struct rpc_clnt *clnt)
83 {
84 struct net *net = rpc_net_ns(clnt);
85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
86
87 spin_lock(&sn->rpc_client_lock);
88 list_add(&clnt->cl_clients, &sn->all_clients);
89 spin_unlock(&sn->rpc_client_lock);
90 }
91
92 static void rpc_unregister_client(struct rpc_clnt *clnt)
93 {
94 struct net *net = rpc_net_ns(clnt);
95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
96
97 spin_lock(&sn->rpc_client_lock);
98 list_del(&clnt->cl_clients);
99 spin_unlock(&sn->rpc_client_lock);
100 }
101
102 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103 {
104 if (clnt->cl_dentry) {
105 if (clnt->cl_auth && clnt->cl_auth->au_ops->pipes_destroy)
106 clnt->cl_auth->au_ops->pipes_destroy(clnt->cl_auth);
107 rpc_remove_client_dir(clnt->cl_dentry);
108 }
109 clnt->cl_dentry = NULL;
110 }
111
112 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
113 {
114 struct net *net = rpc_net_ns(clnt);
115 struct super_block *pipefs_sb;
116
117 pipefs_sb = rpc_get_sb_net(net);
118 if (pipefs_sb) {
119 __rpc_clnt_remove_pipedir(clnt);
120 rpc_put_sb_net(net);
121 }
122 }
123
124 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
125 struct rpc_clnt *clnt,
126 const char *dir_name)
127 {
128 static uint32_t clntid;
129 char name[15];
130 struct qstr q = { .name = name };
131 struct dentry *dir, *dentry;
132 int error;
133
134 dir = rpc_d_lookup_sb(sb, dir_name);
135 if (dir == NULL)
136 return dir;
137 for (;;) {
138 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
139 name[sizeof(name) - 1] = '\0';
140 q.hash = full_name_hash(q.name, q.len);
141 dentry = rpc_create_client_dir(dir, &q, clnt);
142 if (!IS_ERR(dentry))
143 break;
144 error = PTR_ERR(dentry);
145 if (error != -EEXIST) {
146 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
147 " %s/%s, error %d\n",
148 dir_name, name, error);
149 break;
150 }
151 }
152 dput(dir);
153 return dentry;
154 }
155
156 static int
157 rpc_setup_pipedir(struct rpc_clnt *clnt, const char *dir_name)
158 {
159 struct net *net = rpc_net_ns(clnt);
160 struct super_block *pipefs_sb;
161 struct dentry *dentry;
162
163 clnt->cl_dentry = NULL;
164 if (dir_name == NULL)
165 return 0;
166 pipefs_sb = rpc_get_sb_net(net);
167 if (!pipefs_sb)
168 return 0;
169 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt, dir_name);
170 rpc_put_sb_net(net);
171 if (IS_ERR(dentry))
172 return PTR_ERR(dentry);
173 clnt->cl_dentry = dentry;
174 return 0;
175 }
176
177 static inline int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
178 {
179 if (((event == RPC_PIPEFS_MOUNT) && clnt->cl_dentry) ||
180 ((event == RPC_PIPEFS_UMOUNT) && !clnt->cl_dentry))
181 return 1;
182 return 0;
183 }
184
185 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
186 struct super_block *sb)
187 {
188 struct dentry *dentry;
189 int err = 0;
190
191 switch (event) {
192 case RPC_PIPEFS_MOUNT:
193 dentry = rpc_setup_pipedir_sb(sb, clnt,
194 clnt->cl_program->pipe_dir_name);
195 BUG_ON(dentry == NULL);
196 if (IS_ERR(dentry))
197 return PTR_ERR(dentry);
198 clnt->cl_dentry = dentry;
199 if (clnt->cl_auth->au_ops->pipes_create) {
200 err = clnt->cl_auth->au_ops->pipes_create(clnt->cl_auth);
201 if (err)
202 __rpc_clnt_remove_pipedir(clnt);
203 }
204 break;
205 case RPC_PIPEFS_UMOUNT:
206 __rpc_clnt_remove_pipedir(clnt);
207 break;
208 default:
209 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
210 return -ENOTSUPP;
211 }
212 return err;
213 }
214
215 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
216 struct super_block *sb)
217 {
218 int error = 0;
219
220 for (;; clnt = clnt->cl_parent) {
221 if (!rpc_clnt_skip_event(clnt, event))
222 error = __rpc_clnt_handle_event(clnt, event, sb);
223 if (error || clnt == clnt->cl_parent)
224 break;
225 }
226 return error;
227 }
228
229 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
230 {
231 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
232 struct rpc_clnt *clnt;
233
234 spin_lock(&sn->rpc_client_lock);
235 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
236 if (clnt->cl_program->pipe_dir_name == NULL)
237 break;
238 if (rpc_clnt_skip_event(clnt, event))
239 continue;
240 if (atomic_inc_not_zero(&clnt->cl_count) == 0)
241 continue;
242 spin_unlock(&sn->rpc_client_lock);
243 return clnt;
244 }
245 spin_unlock(&sn->rpc_client_lock);
246 return NULL;
247 }
248
249 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
250 void *ptr)
251 {
252 struct super_block *sb = ptr;
253 struct rpc_clnt *clnt;
254 int error = 0;
255
256 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
257 error = __rpc_pipefs_event(clnt, event, sb);
258 rpc_release_client(clnt);
259 if (error)
260 break;
261 }
262 return error;
263 }
264
265 static struct notifier_block rpc_clients_block = {
266 .notifier_call = rpc_pipefs_event,
267 .priority = SUNRPC_PIPEFS_RPC_PRIO,
268 };
269
270 int rpc_clients_notifier_register(void)
271 {
272 return rpc_pipefs_notifier_register(&rpc_clients_block);
273 }
274
275 void rpc_clients_notifier_unregister(void)
276 {
277 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
278 }
279
280 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
281 {
282 clnt->cl_nodelen = strlen(nodename);
283 if (clnt->cl_nodelen > UNX_MAXNODENAME)
284 clnt->cl_nodelen = UNX_MAXNODENAME;
285 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen);
286 }
287
288 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
289 {
290 const struct rpc_program *program = args->program;
291 const struct rpc_version *version;
292 struct rpc_clnt *clnt = NULL;
293 struct rpc_auth *auth;
294 int err;
295
296 /* sanity check the name before trying to print it */
297 dprintk("RPC: creating %s client for %s (xprt %p)\n",
298 program->name, args->servername, xprt);
299
300 err = rpciod_up();
301 if (err)
302 goto out_no_rpciod;
303 err = -EINVAL;
304 if (!xprt)
305 goto out_no_xprt;
306
307 if (args->version >= program->nrvers)
308 goto out_err;
309 version = program->version[args->version];
310 if (version == NULL)
311 goto out_err;
312
313 err = -ENOMEM;
314 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
315 if (!clnt)
316 goto out_err;
317 clnt->cl_parent = clnt;
318
319 rcu_assign_pointer(clnt->cl_xprt, xprt);
320 clnt->cl_procinfo = version->procs;
321 clnt->cl_maxproc = version->nrprocs;
322 clnt->cl_protname = program->name;
323 clnt->cl_prog = args->prognumber ? : program->number;
324 clnt->cl_vers = version->number;
325 clnt->cl_stats = program->stats;
326 clnt->cl_metrics = rpc_alloc_iostats(clnt);
327 err = -ENOMEM;
328 if (clnt->cl_metrics == NULL)
329 goto out_no_stats;
330 clnt->cl_program = program;
331 INIT_LIST_HEAD(&clnt->cl_tasks);
332 spin_lock_init(&clnt->cl_lock);
333
334 if (!xprt_bound(xprt))
335 clnt->cl_autobind = 1;
336
337 clnt->cl_timeout = xprt->timeout;
338 if (args->timeout != NULL) {
339 memcpy(&clnt->cl_timeout_default, args->timeout,
340 sizeof(clnt->cl_timeout_default));
341 clnt->cl_timeout = &clnt->cl_timeout_default;
342 }
343
344 clnt->cl_rtt = &clnt->cl_rtt_default;
345 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
346 clnt->cl_principal = NULL;
347 if (args->client_name) {
348 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
349 if (!clnt->cl_principal)
350 goto out_no_principal;
351 }
352
353 atomic_set(&clnt->cl_count, 1);
354
355 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
356 if (err < 0)
357 goto out_no_path;
358
359 auth = rpcauth_create(args->authflavor, clnt);
360 if (IS_ERR(auth)) {
361 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
362 args->authflavor);
363 err = PTR_ERR(auth);
364 goto out_no_auth;
365 }
366
367 /* save the nodename */
368 rpc_clnt_set_nodename(clnt, utsname()->nodename);
369 rpc_register_client(clnt);
370 return clnt;
371
372 out_no_auth:
373 rpc_clnt_remove_pipedir(clnt);
374 out_no_path:
375 kfree(clnt->cl_principal);
376 out_no_principal:
377 rpc_free_iostats(clnt->cl_metrics);
378 out_no_stats:
379 kfree(clnt);
380 out_err:
381 xprt_put(xprt);
382 out_no_xprt:
383 rpciod_down();
384 out_no_rpciod:
385 return ERR_PTR(err);
386 }
387
388 /**
389 * rpc_create - create an RPC client and transport with one call
390 * @args: rpc_clnt create argument structure
391 *
392 * Creates and initializes an RPC transport and an RPC client.
393 *
394 * It can ping the server in order to determine if it is up, and to see if
395 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
396 * this behavior so asynchronous tasks can also use rpc_create.
397 */
398 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
399 {
400 struct rpc_xprt *xprt;
401 struct rpc_clnt *clnt;
402 struct xprt_create xprtargs = {
403 .net = args->net,
404 .ident = args->protocol,
405 .srcaddr = args->saddress,
406 .dstaddr = args->address,
407 .addrlen = args->addrsize,
408 .servername = args->servername,
409 .bc_xprt = args->bc_xprt,
410 };
411 char servername[48];
412
413 /*
414 * If the caller chooses not to specify a hostname, whip
415 * up a string representation of the passed-in address.
416 */
417 if (xprtargs.servername == NULL) {
418 struct sockaddr_un *sun =
419 (struct sockaddr_un *)args->address;
420 struct sockaddr_in *sin =
421 (struct sockaddr_in *)args->address;
422 struct sockaddr_in6 *sin6 =
423 (struct sockaddr_in6 *)args->address;
424
425 servername[0] = '\0';
426 switch (args->address->sa_family) {
427 case AF_LOCAL:
428 snprintf(servername, sizeof(servername), "%s",
429 sun->sun_path);
430 break;
431 case AF_INET:
432 snprintf(servername, sizeof(servername), "%pI4",
433 &sin->sin_addr.s_addr);
434 break;
435 case AF_INET6:
436 snprintf(servername, sizeof(servername), "%pI6",
437 &sin6->sin6_addr);
438 break;
439 default:
440 /* caller wants default server name, but
441 * address family isn't recognized. */
442 return ERR_PTR(-EINVAL);
443 }
444 xprtargs.servername = servername;
445 }
446
447 xprt = xprt_create_transport(&xprtargs);
448 if (IS_ERR(xprt))
449 return (struct rpc_clnt *)xprt;
450
451 /*
452 * By default, kernel RPC client connects from a reserved port.
453 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
454 * but it is always enabled for rpciod, which handles the connect
455 * operation.
456 */
457 xprt->resvport = 1;
458 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
459 xprt->resvport = 0;
460
461 clnt = rpc_new_client(args, xprt);
462 if (IS_ERR(clnt))
463 return clnt;
464
465 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
466 int err = rpc_ping(clnt);
467 if (err != 0) {
468 rpc_shutdown_client(clnt);
469 return ERR_PTR(err);
470 }
471 }
472
473 clnt->cl_softrtry = 1;
474 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
475 clnt->cl_softrtry = 0;
476
477 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
478 clnt->cl_autobind = 1;
479 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
480 clnt->cl_discrtry = 1;
481 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
482 clnt->cl_chatty = 1;
483
484 return clnt;
485 }
486 EXPORT_SYMBOL_GPL(rpc_create);
487
488 /*
489 * This function clones the RPC client structure. It allows us to share the
490 * same transport while varying parameters such as the authentication
491 * flavour.
492 */
493 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
494 struct rpc_clnt *clnt)
495 {
496 struct rpc_xprt *xprt;
497 struct rpc_clnt *new;
498 int err;
499
500 err = -ENOMEM;
501 rcu_read_lock();
502 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
503 rcu_read_unlock();
504 if (xprt == NULL)
505 goto out_err;
506 args->servername = xprt->servername;
507
508 new = rpc_new_client(args, xprt);
509 if (IS_ERR(new)) {
510 err = PTR_ERR(new);
511 goto out_put;
512 }
513
514 atomic_inc(&clnt->cl_count);
515 new->cl_parent = clnt;
516
517 /* Turn off autobind on clones */
518 new->cl_autobind = 0;
519 new->cl_softrtry = clnt->cl_softrtry;
520 new->cl_discrtry = clnt->cl_discrtry;
521 new->cl_chatty = clnt->cl_chatty;
522 return new;
523
524 out_put:
525 xprt_put(xprt);
526 out_err:
527 dprintk("RPC: %s: returned error %d\n", __func__, err);
528 return ERR_PTR(err);
529 }
530
531 /**
532 * rpc_clone_client - Clone an RPC client structure
533 *
534 * @clnt: RPC client whose parameters are copied
535 *
536 * Returns a fresh RPC client or an ERR_PTR.
537 */
538 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
539 {
540 struct rpc_create_args args = {
541 .program = clnt->cl_program,
542 .prognumber = clnt->cl_prog,
543 .version = clnt->cl_vers,
544 .authflavor = clnt->cl_auth->au_flavor,
545 .client_name = clnt->cl_principal,
546 };
547 return __rpc_clone_client(&args, clnt);
548 }
549 EXPORT_SYMBOL_GPL(rpc_clone_client);
550
551 /**
552 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
553 *
554 * @clnt: RPC client whose parameters are copied
555 * @auth: security flavor for new client
556 *
557 * Returns a fresh RPC client or an ERR_PTR.
558 */
559 struct rpc_clnt *
560 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
561 {
562 struct rpc_create_args args = {
563 .program = clnt->cl_program,
564 .prognumber = clnt->cl_prog,
565 .version = clnt->cl_vers,
566 .authflavor = flavor,
567 .client_name = clnt->cl_principal,
568 };
569 return __rpc_clone_client(&args, clnt);
570 }
571 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
572
573 /*
574 * Kill all tasks for the given client.
575 * XXX: kill their descendants as well?
576 */
577 void rpc_killall_tasks(struct rpc_clnt *clnt)
578 {
579 struct rpc_task *rovr;
580
581
582 if (list_empty(&clnt->cl_tasks))
583 return;
584 dprintk("RPC: killing all tasks for client %p\n", clnt);
585 /*
586 * Spin lock all_tasks to prevent changes...
587 */
588 spin_lock(&clnt->cl_lock);
589 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
590 if (!RPC_IS_ACTIVATED(rovr))
591 continue;
592 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
593 rovr->tk_flags |= RPC_TASK_KILLED;
594 rpc_exit(rovr, -EIO);
595 if (RPC_IS_QUEUED(rovr))
596 rpc_wake_up_queued_task(rovr->tk_waitqueue,
597 rovr);
598 }
599 }
600 spin_unlock(&clnt->cl_lock);
601 }
602 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
603
604 /*
605 * Properly shut down an RPC client, terminating all outstanding
606 * requests.
607 */
608 void rpc_shutdown_client(struct rpc_clnt *clnt)
609 {
610 dprintk_rcu("RPC: shutting down %s client for %s\n",
611 clnt->cl_protname,
612 rcu_dereference(clnt->cl_xprt)->servername);
613
614 while (!list_empty(&clnt->cl_tasks)) {
615 rpc_killall_tasks(clnt);
616 wait_event_timeout(destroy_wait,
617 list_empty(&clnt->cl_tasks), 1*HZ);
618 }
619
620 rpc_release_client(clnt);
621 }
622 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
623
624 /*
625 * Free an RPC client
626 */
627 static void
628 rpc_free_client(struct rpc_clnt *clnt)
629 {
630 dprintk_rcu("RPC: destroying %s client for %s\n",
631 clnt->cl_protname,
632 rcu_dereference(clnt->cl_xprt)->servername);
633 if (clnt->cl_parent != clnt)
634 rpc_release_client(clnt->cl_parent);
635 rpc_unregister_client(clnt);
636 rpc_clnt_remove_pipedir(clnt);
637 rpc_free_iostats(clnt->cl_metrics);
638 kfree(clnt->cl_principal);
639 clnt->cl_metrics = NULL;
640 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
641 rpciod_down();
642 kfree(clnt);
643 }
644
645 /*
646 * Free an RPC client
647 */
648 static void
649 rpc_free_auth(struct rpc_clnt *clnt)
650 {
651 if (clnt->cl_auth == NULL) {
652 rpc_free_client(clnt);
653 return;
654 }
655
656 /*
657 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
658 * release remaining GSS contexts. This mechanism ensures
659 * that it can do so safely.
660 */
661 atomic_inc(&clnt->cl_count);
662 rpcauth_release(clnt->cl_auth);
663 clnt->cl_auth = NULL;
664 if (atomic_dec_and_test(&clnt->cl_count))
665 rpc_free_client(clnt);
666 }
667
668 /*
669 * Release reference to the RPC client
670 */
671 void
672 rpc_release_client(struct rpc_clnt *clnt)
673 {
674 dprintk("RPC: rpc_release_client(%p)\n", clnt);
675
676 if (list_empty(&clnt->cl_tasks))
677 wake_up(&destroy_wait);
678 if (atomic_dec_and_test(&clnt->cl_count))
679 rpc_free_auth(clnt);
680 }
681
682 /**
683 * rpc_bind_new_program - bind a new RPC program to an existing client
684 * @old: old rpc_client
685 * @program: rpc program to set
686 * @vers: rpc program version
687 *
688 * Clones the rpc client and sets up a new RPC program. This is mainly
689 * of use for enabling different RPC programs to share the same transport.
690 * The Sun NFSv2/v3 ACL protocol can do this.
691 */
692 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
693 const struct rpc_program *program,
694 u32 vers)
695 {
696 struct rpc_clnt *clnt;
697 const struct rpc_version *version;
698 int err;
699
700 BUG_ON(vers >= program->nrvers || !program->version[vers]);
701 version = program->version[vers];
702 clnt = rpc_clone_client(old);
703 if (IS_ERR(clnt))
704 goto out;
705 clnt->cl_procinfo = version->procs;
706 clnt->cl_maxproc = version->nrprocs;
707 clnt->cl_protname = program->name;
708 clnt->cl_prog = program->number;
709 clnt->cl_vers = version->number;
710 clnt->cl_stats = program->stats;
711 err = rpc_ping(clnt);
712 if (err != 0) {
713 rpc_shutdown_client(clnt);
714 clnt = ERR_PTR(err);
715 }
716 out:
717 return clnt;
718 }
719 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
720
721 void rpc_task_release_client(struct rpc_task *task)
722 {
723 struct rpc_clnt *clnt = task->tk_client;
724
725 if (clnt != NULL) {
726 /* Remove from client task list */
727 spin_lock(&clnt->cl_lock);
728 list_del(&task->tk_task);
729 spin_unlock(&clnt->cl_lock);
730 task->tk_client = NULL;
731
732 rpc_release_client(clnt);
733 }
734 }
735
736 static
737 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
738 {
739 if (clnt != NULL) {
740 rpc_task_release_client(task);
741 task->tk_client = clnt;
742 atomic_inc(&clnt->cl_count);
743 if (clnt->cl_softrtry)
744 task->tk_flags |= RPC_TASK_SOFT;
745 if (sk_memalloc_socks()) {
746 struct rpc_xprt *xprt;
747
748 rcu_read_lock();
749 xprt = rcu_dereference(clnt->cl_xprt);
750 if (xprt->swapper)
751 task->tk_flags |= RPC_TASK_SWAPPER;
752 rcu_read_unlock();
753 }
754 /* Add to the client's list of all tasks */
755 spin_lock(&clnt->cl_lock);
756 list_add_tail(&task->tk_task, &clnt->cl_tasks);
757 spin_unlock(&clnt->cl_lock);
758 }
759 }
760
761 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
762 {
763 rpc_task_release_client(task);
764 rpc_task_set_client(task, clnt);
765 }
766 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
767
768
769 static void
770 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
771 {
772 if (msg != NULL) {
773 task->tk_msg.rpc_proc = msg->rpc_proc;
774 task->tk_msg.rpc_argp = msg->rpc_argp;
775 task->tk_msg.rpc_resp = msg->rpc_resp;
776 if (msg->rpc_cred != NULL)
777 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
778 }
779 }
780
781 /*
782 * Default callback for async RPC calls
783 */
784 static void
785 rpc_default_callback(struct rpc_task *task, void *data)
786 {
787 }
788
789 static const struct rpc_call_ops rpc_default_ops = {
790 .rpc_call_done = rpc_default_callback,
791 };
792
793 /**
794 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
795 * @task_setup_data: pointer to task initialisation data
796 */
797 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
798 {
799 struct rpc_task *task;
800
801 task = rpc_new_task(task_setup_data);
802 if (IS_ERR(task))
803 goto out;
804
805 rpc_task_set_client(task, task_setup_data->rpc_client);
806 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
807
808 if (task->tk_action == NULL)
809 rpc_call_start(task);
810
811 atomic_inc(&task->tk_count);
812 rpc_execute(task);
813 out:
814 return task;
815 }
816 EXPORT_SYMBOL_GPL(rpc_run_task);
817
818 /**
819 * rpc_call_sync - Perform a synchronous RPC call
820 * @clnt: pointer to RPC client
821 * @msg: RPC call parameters
822 * @flags: RPC call flags
823 */
824 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
825 {
826 struct rpc_task *task;
827 struct rpc_task_setup task_setup_data = {
828 .rpc_client = clnt,
829 .rpc_message = msg,
830 .callback_ops = &rpc_default_ops,
831 .flags = flags,
832 };
833 int status;
834
835 BUG_ON(flags & RPC_TASK_ASYNC);
836
837 task = rpc_run_task(&task_setup_data);
838 if (IS_ERR(task))
839 return PTR_ERR(task);
840 status = task->tk_status;
841 rpc_put_task(task);
842 return status;
843 }
844 EXPORT_SYMBOL_GPL(rpc_call_sync);
845
846 /**
847 * rpc_call_async - Perform an asynchronous RPC call
848 * @clnt: pointer to RPC client
849 * @msg: RPC call parameters
850 * @flags: RPC call flags
851 * @tk_ops: RPC call ops
852 * @data: user call data
853 */
854 int
855 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
856 const struct rpc_call_ops *tk_ops, void *data)
857 {
858 struct rpc_task *task;
859 struct rpc_task_setup task_setup_data = {
860 .rpc_client = clnt,
861 .rpc_message = msg,
862 .callback_ops = tk_ops,
863 .callback_data = data,
864 .flags = flags|RPC_TASK_ASYNC,
865 };
866
867 task = rpc_run_task(&task_setup_data);
868 if (IS_ERR(task))
869 return PTR_ERR(task);
870 rpc_put_task(task);
871 return 0;
872 }
873 EXPORT_SYMBOL_GPL(rpc_call_async);
874
875 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
876 /**
877 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
878 * rpc_execute against it
879 * @req: RPC request
880 * @tk_ops: RPC call ops
881 */
882 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
883 const struct rpc_call_ops *tk_ops)
884 {
885 struct rpc_task *task;
886 struct xdr_buf *xbufp = &req->rq_snd_buf;
887 struct rpc_task_setup task_setup_data = {
888 .callback_ops = tk_ops,
889 };
890
891 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
892 /*
893 * Create an rpc_task to send the data
894 */
895 task = rpc_new_task(&task_setup_data);
896 if (IS_ERR(task)) {
897 xprt_free_bc_request(req);
898 goto out;
899 }
900 task->tk_rqstp = req;
901
902 /*
903 * Set up the xdr_buf length.
904 * This also indicates that the buffer is XDR encoded already.
905 */
906 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
907 xbufp->tail[0].iov_len;
908
909 task->tk_action = call_bc_transmit;
910 atomic_inc(&task->tk_count);
911 BUG_ON(atomic_read(&task->tk_count) != 2);
912 rpc_execute(task);
913
914 out:
915 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
916 return task;
917 }
918 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
919
920 void
921 rpc_call_start(struct rpc_task *task)
922 {
923 task->tk_action = call_start;
924 }
925 EXPORT_SYMBOL_GPL(rpc_call_start);
926
927 /**
928 * rpc_peeraddr - extract remote peer address from clnt's xprt
929 * @clnt: RPC client structure
930 * @buf: target buffer
931 * @bufsize: length of target buffer
932 *
933 * Returns the number of bytes that are actually in the stored address.
934 */
935 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
936 {
937 size_t bytes;
938 struct rpc_xprt *xprt;
939
940 rcu_read_lock();
941 xprt = rcu_dereference(clnt->cl_xprt);
942
943 bytes = xprt->addrlen;
944 if (bytes > bufsize)
945 bytes = bufsize;
946 memcpy(buf, &xprt->addr, bytes);
947 rcu_read_unlock();
948
949 return bytes;
950 }
951 EXPORT_SYMBOL_GPL(rpc_peeraddr);
952
953 /**
954 * rpc_peeraddr2str - return remote peer address in printable format
955 * @clnt: RPC client structure
956 * @format: address format
957 *
958 * NB: the lifetime of the memory referenced by the returned pointer is
959 * the same as the rpc_xprt itself. As long as the caller uses this
960 * pointer, it must hold the RCU read lock.
961 */
962 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
963 enum rpc_display_format_t format)
964 {
965 struct rpc_xprt *xprt;
966
967 xprt = rcu_dereference(clnt->cl_xprt);
968
969 if (xprt->address_strings[format] != NULL)
970 return xprt->address_strings[format];
971 else
972 return "unprintable";
973 }
974 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
975
976 static const struct sockaddr_in rpc_inaddr_loopback = {
977 .sin_family = AF_INET,
978 .sin_addr.s_addr = htonl(INADDR_ANY),
979 };
980
981 static const struct sockaddr_in6 rpc_in6addr_loopback = {
982 .sin6_family = AF_INET6,
983 .sin6_addr = IN6ADDR_ANY_INIT,
984 };
985
986 /*
987 * Try a getsockname() on a connected datagram socket. Using a
988 * connected datagram socket prevents leaving a socket in TIME_WAIT.
989 * This conserves the ephemeral port number space.
990 *
991 * Returns zero and fills in "buf" if successful; otherwise, a
992 * negative errno is returned.
993 */
994 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
995 struct sockaddr *buf, int buflen)
996 {
997 struct socket *sock;
998 int err;
999
1000 err = __sock_create(net, sap->sa_family,
1001 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1002 if (err < 0) {
1003 dprintk("RPC: can't create UDP socket (%d)\n", err);
1004 goto out;
1005 }
1006
1007 switch (sap->sa_family) {
1008 case AF_INET:
1009 err = kernel_bind(sock,
1010 (struct sockaddr *)&rpc_inaddr_loopback,
1011 sizeof(rpc_inaddr_loopback));
1012 break;
1013 case AF_INET6:
1014 err = kernel_bind(sock,
1015 (struct sockaddr *)&rpc_in6addr_loopback,
1016 sizeof(rpc_in6addr_loopback));
1017 break;
1018 default:
1019 err = -EAFNOSUPPORT;
1020 goto out;
1021 }
1022 if (err < 0) {
1023 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1024 goto out_release;
1025 }
1026
1027 err = kernel_connect(sock, sap, salen, 0);
1028 if (err < 0) {
1029 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1030 goto out_release;
1031 }
1032
1033 err = kernel_getsockname(sock, buf, &buflen);
1034 if (err < 0) {
1035 dprintk("RPC: getsockname failed (%d)\n", err);
1036 goto out_release;
1037 }
1038
1039 err = 0;
1040 if (buf->sa_family == AF_INET6) {
1041 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1042 sin6->sin6_scope_id = 0;
1043 }
1044 dprintk("RPC: %s succeeded\n", __func__);
1045
1046 out_release:
1047 sock_release(sock);
1048 out:
1049 return err;
1050 }
1051
1052 /*
1053 * Scraping a connected socket failed, so we don't have a useable
1054 * local address. Fallback: generate an address that will prevent
1055 * the server from calling us back.
1056 *
1057 * Returns zero and fills in "buf" if successful; otherwise, a
1058 * negative errno is returned.
1059 */
1060 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1061 {
1062 switch (family) {
1063 case AF_INET:
1064 if (buflen < sizeof(rpc_inaddr_loopback))
1065 return -EINVAL;
1066 memcpy(buf, &rpc_inaddr_loopback,
1067 sizeof(rpc_inaddr_loopback));
1068 break;
1069 case AF_INET6:
1070 if (buflen < sizeof(rpc_in6addr_loopback))
1071 return -EINVAL;
1072 memcpy(buf, &rpc_in6addr_loopback,
1073 sizeof(rpc_in6addr_loopback));
1074 default:
1075 dprintk("RPC: %s: address family not supported\n",
1076 __func__);
1077 return -EAFNOSUPPORT;
1078 }
1079 dprintk("RPC: %s: succeeded\n", __func__);
1080 return 0;
1081 }
1082
1083 /**
1084 * rpc_localaddr - discover local endpoint address for an RPC client
1085 * @clnt: RPC client structure
1086 * @buf: target buffer
1087 * @buflen: size of target buffer, in bytes
1088 *
1089 * Returns zero and fills in "buf" and "buflen" if successful;
1090 * otherwise, a negative errno is returned.
1091 *
1092 * This works even if the underlying transport is not currently connected,
1093 * or if the upper layer never previously provided a source address.
1094 *
1095 * The result of this function call is transient: multiple calls in
1096 * succession may give different results, depending on how local
1097 * networking configuration changes over time.
1098 */
1099 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1100 {
1101 struct sockaddr_storage address;
1102 struct sockaddr *sap = (struct sockaddr *)&address;
1103 struct rpc_xprt *xprt;
1104 struct net *net;
1105 size_t salen;
1106 int err;
1107
1108 rcu_read_lock();
1109 xprt = rcu_dereference(clnt->cl_xprt);
1110 salen = xprt->addrlen;
1111 memcpy(sap, &xprt->addr, salen);
1112 net = get_net(xprt->xprt_net);
1113 rcu_read_unlock();
1114
1115 rpc_set_port(sap, 0);
1116 err = rpc_sockname(net, sap, salen, buf, buflen);
1117 put_net(net);
1118 if (err != 0)
1119 /* Couldn't discover local address, return ANYADDR */
1120 return rpc_anyaddr(sap->sa_family, buf, buflen);
1121 return 0;
1122 }
1123 EXPORT_SYMBOL_GPL(rpc_localaddr);
1124
1125 void
1126 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1127 {
1128 struct rpc_xprt *xprt;
1129
1130 rcu_read_lock();
1131 xprt = rcu_dereference(clnt->cl_xprt);
1132 if (xprt->ops->set_buffer_size)
1133 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1134 rcu_read_unlock();
1135 }
1136 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1137
1138 /**
1139 * rpc_protocol - Get transport protocol number for an RPC client
1140 * @clnt: RPC client to query
1141 *
1142 */
1143 int rpc_protocol(struct rpc_clnt *clnt)
1144 {
1145 int protocol;
1146
1147 rcu_read_lock();
1148 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1149 rcu_read_unlock();
1150 return protocol;
1151 }
1152 EXPORT_SYMBOL_GPL(rpc_protocol);
1153
1154 /**
1155 * rpc_net_ns - Get the network namespace for this RPC client
1156 * @clnt: RPC client to query
1157 *
1158 */
1159 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1160 {
1161 struct net *ret;
1162
1163 rcu_read_lock();
1164 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1165 rcu_read_unlock();
1166 return ret;
1167 }
1168 EXPORT_SYMBOL_GPL(rpc_net_ns);
1169
1170 /**
1171 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1172 * @clnt: RPC client to query
1173 *
1174 * For stream transports, this is one RPC record fragment (see RFC
1175 * 1831), as we don't support multi-record requests yet. For datagram
1176 * transports, this is the size of an IP packet minus the IP, UDP, and
1177 * RPC header sizes.
1178 */
1179 size_t rpc_max_payload(struct rpc_clnt *clnt)
1180 {
1181 size_t ret;
1182
1183 rcu_read_lock();
1184 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1185 rcu_read_unlock();
1186 return ret;
1187 }
1188 EXPORT_SYMBOL_GPL(rpc_max_payload);
1189
1190 /**
1191 * rpc_force_rebind - force transport to check that remote port is unchanged
1192 * @clnt: client to rebind
1193 *
1194 */
1195 void rpc_force_rebind(struct rpc_clnt *clnt)
1196 {
1197 if (clnt->cl_autobind) {
1198 rcu_read_lock();
1199 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1200 rcu_read_unlock();
1201 }
1202 }
1203 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1204
1205 /*
1206 * Restart an (async) RPC call from the call_prepare state.
1207 * Usually called from within the exit handler.
1208 */
1209 int
1210 rpc_restart_call_prepare(struct rpc_task *task)
1211 {
1212 if (RPC_ASSASSINATED(task))
1213 return 0;
1214 task->tk_action = call_start;
1215 if (task->tk_ops->rpc_call_prepare != NULL)
1216 task->tk_action = rpc_prepare_task;
1217 return 1;
1218 }
1219 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1220
1221 /*
1222 * Restart an (async) RPC call. Usually called from within the
1223 * exit handler.
1224 */
1225 int
1226 rpc_restart_call(struct rpc_task *task)
1227 {
1228 if (RPC_ASSASSINATED(task))
1229 return 0;
1230 task->tk_action = call_start;
1231 return 1;
1232 }
1233 EXPORT_SYMBOL_GPL(rpc_restart_call);
1234
1235 #ifdef RPC_DEBUG
1236 static const char *rpc_proc_name(const struct rpc_task *task)
1237 {
1238 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1239
1240 if (proc) {
1241 if (proc->p_name)
1242 return proc->p_name;
1243 else
1244 return "NULL";
1245 } else
1246 return "no proc";
1247 }
1248 #endif
1249
1250 /*
1251 * 0. Initial state
1252 *
1253 * Other FSM states can be visited zero or more times, but
1254 * this state is visited exactly once for each RPC.
1255 */
1256 static void
1257 call_start(struct rpc_task *task)
1258 {
1259 struct rpc_clnt *clnt = task->tk_client;
1260
1261 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1262 clnt->cl_protname, clnt->cl_vers,
1263 rpc_proc_name(task),
1264 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1265
1266 /* Increment call count */
1267 task->tk_msg.rpc_proc->p_count++;
1268 clnt->cl_stats->rpccnt++;
1269 task->tk_action = call_reserve;
1270 }
1271
1272 /*
1273 * 1. Reserve an RPC call slot
1274 */
1275 static void
1276 call_reserve(struct rpc_task *task)
1277 {
1278 dprint_status(task);
1279
1280 task->tk_status = 0;
1281 task->tk_action = call_reserveresult;
1282 xprt_reserve(task);
1283 }
1284
1285 /*
1286 * 1b. Grok the result of xprt_reserve()
1287 */
1288 static void
1289 call_reserveresult(struct rpc_task *task)
1290 {
1291 int status = task->tk_status;
1292
1293 dprint_status(task);
1294
1295 /*
1296 * After a call to xprt_reserve(), we must have either
1297 * a request slot or else an error status.
1298 */
1299 task->tk_status = 0;
1300 if (status >= 0) {
1301 if (task->tk_rqstp) {
1302 task->tk_action = call_refresh;
1303 return;
1304 }
1305
1306 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1307 __func__, status);
1308 rpc_exit(task, -EIO);
1309 return;
1310 }
1311
1312 /*
1313 * Even though there was an error, we may have acquired
1314 * a request slot somehow. Make sure not to leak it.
1315 */
1316 if (task->tk_rqstp) {
1317 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1318 __func__, status);
1319 xprt_release(task);
1320 }
1321
1322 switch (status) {
1323 case -ENOMEM:
1324 rpc_delay(task, HZ >> 2);
1325 case -EAGAIN: /* woken up; retry */
1326 task->tk_action = call_reserve;
1327 return;
1328 case -EIO: /* probably a shutdown */
1329 break;
1330 default:
1331 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1332 __func__, status);
1333 break;
1334 }
1335 rpc_exit(task, status);
1336 }
1337
1338 /*
1339 * 2. Bind and/or refresh the credentials
1340 */
1341 static void
1342 call_refresh(struct rpc_task *task)
1343 {
1344 dprint_status(task);
1345
1346 task->tk_action = call_refreshresult;
1347 task->tk_status = 0;
1348 task->tk_client->cl_stats->rpcauthrefresh++;
1349 rpcauth_refreshcred(task);
1350 }
1351
1352 /*
1353 * 2a. Process the results of a credential refresh
1354 */
1355 static void
1356 call_refreshresult(struct rpc_task *task)
1357 {
1358 int status = task->tk_status;
1359
1360 dprint_status(task);
1361
1362 task->tk_status = 0;
1363 task->tk_action = call_refresh;
1364 switch (status) {
1365 case 0:
1366 if (rpcauth_uptodatecred(task))
1367 task->tk_action = call_allocate;
1368 return;
1369 case -ETIMEDOUT:
1370 rpc_delay(task, 3*HZ);
1371 case -EAGAIN:
1372 status = -EACCES;
1373 if (!task->tk_cred_retry)
1374 break;
1375 task->tk_cred_retry--;
1376 dprintk("RPC: %5u %s: retry refresh creds\n",
1377 task->tk_pid, __func__);
1378 return;
1379 }
1380 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1381 task->tk_pid, __func__, status);
1382 rpc_exit(task, status);
1383 }
1384
1385 /*
1386 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1387 * (Note: buffer memory is freed in xprt_release).
1388 */
1389 static void
1390 call_allocate(struct rpc_task *task)
1391 {
1392 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1393 struct rpc_rqst *req = task->tk_rqstp;
1394 struct rpc_xprt *xprt = task->tk_xprt;
1395 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1396
1397 dprint_status(task);
1398
1399 task->tk_status = 0;
1400 task->tk_action = call_bind;
1401
1402 if (req->rq_buffer)
1403 return;
1404
1405 if (proc->p_proc != 0) {
1406 BUG_ON(proc->p_arglen == 0);
1407 if (proc->p_decode != NULL)
1408 BUG_ON(proc->p_replen == 0);
1409 }
1410
1411 /*
1412 * Calculate the size (in quads) of the RPC call
1413 * and reply headers, and convert both values
1414 * to byte sizes.
1415 */
1416 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1417 req->rq_callsize <<= 2;
1418 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1419 req->rq_rcvsize <<= 2;
1420
1421 req->rq_buffer = xprt->ops->buf_alloc(task,
1422 req->rq_callsize + req->rq_rcvsize);
1423 if (req->rq_buffer != NULL)
1424 return;
1425
1426 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1427
1428 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1429 task->tk_action = call_allocate;
1430 rpc_delay(task, HZ>>4);
1431 return;
1432 }
1433
1434 rpc_exit(task, -ERESTARTSYS);
1435 }
1436
1437 static inline int
1438 rpc_task_need_encode(struct rpc_task *task)
1439 {
1440 return task->tk_rqstp->rq_snd_buf.len == 0;
1441 }
1442
1443 static inline void
1444 rpc_task_force_reencode(struct rpc_task *task)
1445 {
1446 task->tk_rqstp->rq_snd_buf.len = 0;
1447 task->tk_rqstp->rq_bytes_sent = 0;
1448 }
1449
1450 static inline void
1451 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1452 {
1453 buf->head[0].iov_base = start;
1454 buf->head[0].iov_len = len;
1455 buf->tail[0].iov_len = 0;
1456 buf->page_len = 0;
1457 buf->flags = 0;
1458 buf->len = 0;
1459 buf->buflen = len;
1460 }
1461
1462 /*
1463 * 3. Encode arguments of an RPC call
1464 */
1465 static void
1466 rpc_xdr_encode(struct rpc_task *task)
1467 {
1468 struct rpc_rqst *req = task->tk_rqstp;
1469 kxdreproc_t encode;
1470 __be32 *p;
1471
1472 dprint_status(task);
1473
1474 rpc_xdr_buf_init(&req->rq_snd_buf,
1475 req->rq_buffer,
1476 req->rq_callsize);
1477 rpc_xdr_buf_init(&req->rq_rcv_buf,
1478 (char *)req->rq_buffer + req->rq_callsize,
1479 req->rq_rcvsize);
1480
1481 p = rpc_encode_header(task);
1482 if (p == NULL) {
1483 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1484 rpc_exit(task, -EIO);
1485 return;
1486 }
1487
1488 encode = task->tk_msg.rpc_proc->p_encode;
1489 if (encode == NULL)
1490 return;
1491
1492 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1493 task->tk_msg.rpc_argp);
1494 }
1495
1496 /*
1497 * 4. Get the server port number if not yet set
1498 */
1499 static void
1500 call_bind(struct rpc_task *task)
1501 {
1502 struct rpc_xprt *xprt = task->tk_xprt;
1503
1504 dprint_status(task);
1505
1506 task->tk_action = call_connect;
1507 if (!xprt_bound(xprt)) {
1508 task->tk_action = call_bind_status;
1509 task->tk_timeout = xprt->bind_timeout;
1510 xprt->ops->rpcbind(task);
1511 }
1512 }
1513
1514 /*
1515 * 4a. Sort out bind result
1516 */
1517 static void
1518 call_bind_status(struct rpc_task *task)
1519 {
1520 int status = -EIO;
1521
1522 if (task->tk_status >= 0) {
1523 dprint_status(task);
1524 task->tk_status = 0;
1525 task->tk_action = call_connect;
1526 return;
1527 }
1528
1529 trace_rpc_bind_status(task);
1530 switch (task->tk_status) {
1531 case -ENOMEM:
1532 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1533 rpc_delay(task, HZ >> 2);
1534 goto retry_timeout;
1535 case -EACCES:
1536 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1537 "unavailable\n", task->tk_pid);
1538 /* fail immediately if this is an RPC ping */
1539 if (task->tk_msg.rpc_proc->p_proc == 0) {
1540 status = -EOPNOTSUPP;
1541 break;
1542 }
1543 if (task->tk_rebind_retry == 0)
1544 break;
1545 task->tk_rebind_retry--;
1546 rpc_delay(task, 3*HZ);
1547 goto retry_timeout;
1548 case -ETIMEDOUT:
1549 dprintk("RPC: %5u rpcbind request timed out\n",
1550 task->tk_pid);
1551 goto retry_timeout;
1552 case -EPFNOSUPPORT:
1553 /* server doesn't support any rpcbind version we know of */
1554 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1555 task->tk_pid);
1556 break;
1557 case -EPROTONOSUPPORT:
1558 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1559 task->tk_pid);
1560 task->tk_status = 0;
1561 task->tk_action = call_bind;
1562 return;
1563 case -ECONNREFUSED: /* connection problems */
1564 case -ECONNRESET:
1565 case -ENOTCONN:
1566 case -EHOSTDOWN:
1567 case -EHOSTUNREACH:
1568 case -ENETUNREACH:
1569 case -EPIPE:
1570 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1571 task->tk_pid, task->tk_status);
1572 if (!RPC_IS_SOFTCONN(task)) {
1573 rpc_delay(task, 5*HZ);
1574 goto retry_timeout;
1575 }
1576 status = task->tk_status;
1577 break;
1578 default:
1579 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1580 task->tk_pid, -task->tk_status);
1581 }
1582
1583 rpc_exit(task, status);
1584 return;
1585
1586 retry_timeout:
1587 task->tk_action = call_timeout;
1588 }
1589
1590 /*
1591 * 4b. Connect to the RPC server
1592 */
1593 static void
1594 call_connect(struct rpc_task *task)
1595 {
1596 struct rpc_xprt *xprt = task->tk_xprt;
1597
1598 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1599 task->tk_pid, xprt,
1600 (xprt_connected(xprt) ? "is" : "is not"));
1601
1602 task->tk_action = call_transmit;
1603 if (!xprt_connected(xprt)) {
1604 task->tk_action = call_connect_status;
1605 if (task->tk_status < 0)
1606 return;
1607 xprt_connect(task);
1608 }
1609 }
1610
1611 /*
1612 * 4c. Sort out connect result
1613 */
1614 static void
1615 call_connect_status(struct rpc_task *task)
1616 {
1617 struct rpc_clnt *clnt = task->tk_client;
1618 int status = task->tk_status;
1619
1620 dprint_status(task);
1621
1622 task->tk_status = 0;
1623 if (status >= 0 || status == -EAGAIN) {
1624 clnt->cl_stats->netreconn++;
1625 task->tk_action = call_transmit;
1626 return;
1627 }
1628
1629 trace_rpc_connect_status(task, status);
1630 switch (status) {
1631 /* if soft mounted, test if we've timed out */
1632 case -ETIMEDOUT:
1633 task->tk_action = call_timeout;
1634 break;
1635 default:
1636 rpc_exit(task, -EIO);
1637 }
1638 }
1639
1640 /*
1641 * 5. Transmit the RPC request, and wait for reply
1642 */
1643 static void
1644 call_transmit(struct rpc_task *task)
1645 {
1646 dprint_status(task);
1647
1648 task->tk_action = call_status;
1649 if (task->tk_status < 0)
1650 return;
1651 task->tk_status = xprt_prepare_transmit(task);
1652 if (task->tk_status != 0)
1653 return;
1654 task->tk_action = call_transmit_status;
1655 /* Encode here so that rpcsec_gss can use correct sequence number. */
1656 if (rpc_task_need_encode(task)) {
1657 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1658 rpc_xdr_encode(task);
1659 /* Did the encode result in an error condition? */
1660 if (task->tk_status != 0) {
1661 /* Was the error nonfatal? */
1662 if (task->tk_status == -EAGAIN)
1663 rpc_delay(task, HZ >> 4);
1664 else
1665 rpc_exit(task, task->tk_status);
1666 return;
1667 }
1668 }
1669 xprt_transmit(task);
1670 if (task->tk_status < 0)
1671 return;
1672 /*
1673 * On success, ensure that we call xprt_end_transmit() before sleeping
1674 * in order to allow access to the socket to other RPC requests.
1675 */
1676 call_transmit_status(task);
1677 if (rpc_reply_expected(task))
1678 return;
1679 task->tk_action = rpc_exit_task;
1680 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1681 }
1682
1683 /*
1684 * 5a. Handle cleanup after a transmission
1685 */
1686 static void
1687 call_transmit_status(struct rpc_task *task)
1688 {
1689 task->tk_action = call_status;
1690
1691 /*
1692 * Common case: success. Force the compiler to put this
1693 * test first.
1694 */
1695 if (task->tk_status == 0) {
1696 xprt_end_transmit(task);
1697 rpc_task_force_reencode(task);
1698 return;
1699 }
1700
1701 switch (task->tk_status) {
1702 case -EAGAIN:
1703 break;
1704 default:
1705 dprint_status(task);
1706 xprt_end_transmit(task);
1707 rpc_task_force_reencode(task);
1708 break;
1709 /*
1710 * Special cases: if we've been waiting on the
1711 * socket's write_space() callback, or if the
1712 * socket just returned a connection error,
1713 * then hold onto the transport lock.
1714 */
1715 case -ECONNREFUSED:
1716 case -EHOSTDOWN:
1717 case -EHOSTUNREACH:
1718 case -ENETUNREACH:
1719 if (RPC_IS_SOFTCONN(task)) {
1720 xprt_end_transmit(task);
1721 rpc_exit(task, task->tk_status);
1722 break;
1723 }
1724 case -ECONNRESET:
1725 case -ENOTCONN:
1726 case -EPIPE:
1727 rpc_task_force_reencode(task);
1728 }
1729 }
1730
1731 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1732 /*
1733 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1734 * addition, disconnect on connectivity errors.
1735 */
1736 static void
1737 call_bc_transmit(struct rpc_task *task)
1738 {
1739 struct rpc_rqst *req = task->tk_rqstp;
1740
1741 BUG_ON(task->tk_status != 0);
1742 task->tk_status = xprt_prepare_transmit(task);
1743 if (task->tk_status == -EAGAIN) {
1744 /*
1745 * Could not reserve the transport. Try again after the
1746 * transport is released.
1747 */
1748 task->tk_status = 0;
1749 task->tk_action = call_bc_transmit;
1750 return;
1751 }
1752
1753 task->tk_action = rpc_exit_task;
1754 if (task->tk_status < 0) {
1755 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1756 "error: %d\n", task->tk_status);
1757 return;
1758 }
1759
1760 xprt_transmit(task);
1761 xprt_end_transmit(task);
1762 dprint_status(task);
1763 switch (task->tk_status) {
1764 case 0:
1765 /* Success */
1766 break;
1767 case -EHOSTDOWN:
1768 case -EHOSTUNREACH:
1769 case -ENETUNREACH:
1770 case -ETIMEDOUT:
1771 /*
1772 * Problem reaching the server. Disconnect and let the
1773 * forechannel reestablish the connection. The server will
1774 * have to retransmit the backchannel request and we'll
1775 * reprocess it. Since these ops are idempotent, there's no
1776 * need to cache our reply at this time.
1777 */
1778 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1779 "error: %d\n", task->tk_status);
1780 xprt_conditional_disconnect(task->tk_xprt,
1781 req->rq_connect_cookie);
1782 break;
1783 default:
1784 /*
1785 * We were unable to reply and will have to drop the
1786 * request. The server should reconnect and retransmit.
1787 */
1788 BUG_ON(task->tk_status == -EAGAIN);
1789 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1790 "error: %d\n", task->tk_status);
1791 break;
1792 }
1793 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1794 }
1795 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1796
1797 /*
1798 * 6. Sort out the RPC call status
1799 */
1800 static void
1801 call_status(struct rpc_task *task)
1802 {
1803 struct rpc_clnt *clnt = task->tk_client;
1804 struct rpc_rqst *req = task->tk_rqstp;
1805 int status;
1806
1807 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1808 task->tk_status = req->rq_reply_bytes_recvd;
1809
1810 dprint_status(task);
1811
1812 status = task->tk_status;
1813 if (status >= 0) {
1814 task->tk_action = call_decode;
1815 return;
1816 }
1817
1818 trace_rpc_call_status(task);
1819 task->tk_status = 0;
1820 switch(status) {
1821 case -EHOSTDOWN:
1822 case -EHOSTUNREACH:
1823 case -ENETUNREACH:
1824 /*
1825 * Delay any retries for 3 seconds, then handle as if it
1826 * were a timeout.
1827 */
1828 rpc_delay(task, 3*HZ);
1829 case -ETIMEDOUT:
1830 task->tk_action = call_timeout;
1831 if (task->tk_client->cl_discrtry)
1832 xprt_conditional_disconnect(task->tk_xprt,
1833 req->rq_connect_cookie);
1834 break;
1835 case -ECONNRESET:
1836 case -ECONNREFUSED:
1837 rpc_force_rebind(clnt);
1838 rpc_delay(task, 3*HZ);
1839 case -EPIPE:
1840 case -ENOTCONN:
1841 task->tk_action = call_bind;
1842 break;
1843 case -EAGAIN:
1844 task->tk_action = call_transmit;
1845 break;
1846 case -EIO:
1847 /* shutdown or soft timeout */
1848 rpc_exit(task, status);
1849 break;
1850 default:
1851 if (clnt->cl_chatty)
1852 printk("%s: RPC call returned error %d\n",
1853 clnt->cl_protname, -status);
1854 rpc_exit(task, status);
1855 }
1856 }
1857
1858 /*
1859 * 6a. Handle RPC timeout
1860 * We do not release the request slot, so we keep using the
1861 * same XID for all retransmits.
1862 */
1863 static void
1864 call_timeout(struct rpc_task *task)
1865 {
1866 struct rpc_clnt *clnt = task->tk_client;
1867
1868 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1869 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1870 goto retry;
1871 }
1872
1873 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1874 task->tk_timeouts++;
1875
1876 if (RPC_IS_SOFTCONN(task)) {
1877 rpc_exit(task, -ETIMEDOUT);
1878 return;
1879 }
1880 if (RPC_IS_SOFT(task)) {
1881 if (clnt->cl_chatty) {
1882 rcu_read_lock();
1883 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1884 clnt->cl_protname,
1885 rcu_dereference(clnt->cl_xprt)->servername);
1886 rcu_read_unlock();
1887 }
1888 if (task->tk_flags & RPC_TASK_TIMEOUT)
1889 rpc_exit(task, -ETIMEDOUT);
1890 else
1891 rpc_exit(task, -EIO);
1892 return;
1893 }
1894
1895 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1896 task->tk_flags |= RPC_CALL_MAJORSEEN;
1897 if (clnt->cl_chatty) {
1898 rcu_read_lock();
1899 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1900 clnt->cl_protname,
1901 rcu_dereference(clnt->cl_xprt)->servername);
1902 rcu_read_unlock();
1903 }
1904 }
1905 rpc_force_rebind(clnt);
1906 /*
1907 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1908 * event? RFC2203 requires the server to drop all such requests.
1909 */
1910 rpcauth_invalcred(task);
1911
1912 retry:
1913 clnt->cl_stats->rpcretrans++;
1914 task->tk_action = call_bind;
1915 task->tk_status = 0;
1916 }
1917
1918 /*
1919 * 7. Decode the RPC reply
1920 */
1921 static void
1922 call_decode(struct rpc_task *task)
1923 {
1924 struct rpc_clnt *clnt = task->tk_client;
1925 struct rpc_rqst *req = task->tk_rqstp;
1926 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
1927 __be32 *p;
1928
1929 dprint_status(task);
1930
1931 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1932 if (clnt->cl_chatty) {
1933 rcu_read_lock();
1934 printk(KERN_NOTICE "%s: server %s OK\n",
1935 clnt->cl_protname,
1936 rcu_dereference(clnt->cl_xprt)->servername);
1937 rcu_read_unlock();
1938 }
1939 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1940 }
1941
1942 /*
1943 * Ensure that we see all writes made by xprt_complete_rqst()
1944 * before it changed req->rq_reply_bytes_recvd.
1945 */
1946 smp_rmb();
1947 req->rq_rcv_buf.len = req->rq_private_buf.len;
1948
1949 /* Check that the softirq receive buffer is valid */
1950 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1951 sizeof(req->rq_rcv_buf)) != 0);
1952
1953 if (req->rq_rcv_buf.len < 12) {
1954 if (!RPC_IS_SOFT(task)) {
1955 task->tk_action = call_bind;
1956 clnt->cl_stats->rpcretrans++;
1957 goto out_retry;
1958 }
1959 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1960 clnt->cl_protname, task->tk_status);
1961 task->tk_action = call_timeout;
1962 goto out_retry;
1963 }
1964
1965 p = rpc_verify_header(task);
1966 if (IS_ERR(p)) {
1967 if (p == ERR_PTR(-EAGAIN))
1968 goto out_retry;
1969 return;
1970 }
1971
1972 task->tk_action = rpc_exit_task;
1973
1974 if (decode) {
1975 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1976 task->tk_msg.rpc_resp);
1977 }
1978 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1979 task->tk_status);
1980 return;
1981 out_retry:
1982 task->tk_status = 0;
1983 /* Note: rpc_verify_header() may have freed the RPC slot */
1984 if (task->tk_rqstp == req) {
1985 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
1986 if (task->tk_client->cl_discrtry)
1987 xprt_conditional_disconnect(task->tk_xprt,
1988 req->rq_connect_cookie);
1989 }
1990 }
1991
1992 static __be32 *
1993 rpc_encode_header(struct rpc_task *task)
1994 {
1995 struct rpc_clnt *clnt = task->tk_client;
1996 struct rpc_rqst *req = task->tk_rqstp;
1997 __be32 *p = req->rq_svec[0].iov_base;
1998
1999 /* FIXME: check buffer size? */
2000
2001 p = xprt_skip_transport_header(task->tk_xprt, p);
2002 *p++ = req->rq_xid; /* XID */
2003 *p++ = htonl(RPC_CALL); /* CALL */
2004 *p++ = htonl(RPC_VERSION); /* RPC version */
2005 *p++ = htonl(clnt->cl_prog); /* program number */
2006 *p++ = htonl(clnt->cl_vers); /* program version */
2007 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2008 p = rpcauth_marshcred(task, p);
2009 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2010 return p;
2011 }
2012
2013 static __be32 *
2014 rpc_verify_header(struct rpc_task *task)
2015 {
2016 struct rpc_clnt *clnt = task->tk_client;
2017 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2018 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2019 __be32 *p = iov->iov_base;
2020 u32 n;
2021 int error = -EACCES;
2022
2023 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2024 /* RFC-1014 says that the representation of XDR data must be a
2025 * multiple of four bytes
2026 * - if it isn't pointer subtraction in the NFS client may give
2027 * undefined results
2028 */
2029 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2030 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2031 task->tk_rqstp->rq_rcv_buf.len);
2032 goto out_eio;
2033 }
2034 if ((len -= 3) < 0)
2035 goto out_overflow;
2036
2037 p += 1; /* skip XID */
2038 if ((n = ntohl(*p++)) != RPC_REPLY) {
2039 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2040 task->tk_pid, __func__, n);
2041 goto out_garbage;
2042 }
2043
2044 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2045 if (--len < 0)
2046 goto out_overflow;
2047 switch ((n = ntohl(*p++))) {
2048 case RPC_AUTH_ERROR:
2049 break;
2050 case RPC_MISMATCH:
2051 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2052 task->tk_pid, __func__);
2053 error = -EPROTONOSUPPORT;
2054 goto out_err;
2055 default:
2056 dprintk("RPC: %5u %s: RPC call rejected, "
2057 "unknown error: %x\n",
2058 task->tk_pid, __func__, n);
2059 goto out_eio;
2060 }
2061 if (--len < 0)
2062 goto out_overflow;
2063 switch ((n = ntohl(*p++))) {
2064 case RPC_AUTH_REJECTEDCRED:
2065 case RPC_AUTH_REJECTEDVERF:
2066 case RPCSEC_GSS_CREDPROBLEM:
2067 case RPCSEC_GSS_CTXPROBLEM:
2068 if (!task->tk_cred_retry)
2069 break;
2070 task->tk_cred_retry--;
2071 dprintk("RPC: %5u %s: retry stale creds\n",
2072 task->tk_pid, __func__);
2073 rpcauth_invalcred(task);
2074 /* Ensure we obtain a new XID! */
2075 xprt_release(task);
2076 task->tk_action = call_reserve;
2077 goto out_retry;
2078 case RPC_AUTH_BADCRED:
2079 case RPC_AUTH_BADVERF:
2080 /* possibly garbled cred/verf? */
2081 if (!task->tk_garb_retry)
2082 break;
2083 task->tk_garb_retry--;
2084 dprintk("RPC: %5u %s: retry garbled creds\n",
2085 task->tk_pid, __func__);
2086 task->tk_action = call_bind;
2087 goto out_retry;
2088 case RPC_AUTH_TOOWEAK:
2089 rcu_read_lock();
2090 printk(KERN_NOTICE "RPC: server %s requires stronger "
2091 "authentication.\n",
2092 rcu_dereference(clnt->cl_xprt)->servername);
2093 rcu_read_unlock();
2094 break;
2095 default:
2096 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2097 task->tk_pid, __func__, n);
2098 error = -EIO;
2099 }
2100 dprintk("RPC: %5u %s: call rejected %d\n",
2101 task->tk_pid, __func__, n);
2102 goto out_err;
2103 }
2104 if (!(p = rpcauth_checkverf(task, p))) {
2105 dprintk("RPC: %5u %s: auth check failed\n",
2106 task->tk_pid, __func__);
2107 goto out_garbage; /* bad verifier, retry */
2108 }
2109 len = p - (__be32 *)iov->iov_base - 1;
2110 if (len < 0)
2111 goto out_overflow;
2112 switch ((n = ntohl(*p++))) {
2113 case RPC_SUCCESS:
2114 return p;
2115 case RPC_PROG_UNAVAIL:
2116 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2117 "by server %s\n", task->tk_pid, __func__,
2118 (unsigned int)clnt->cl_prog,
2119 rcu_dereference(clnt->cl_xprt)->servername);
2120 error = -EPFNOSUPPORT;
2121 goto out_err;
2122 case RPC_PROG_MISMATCH:
2123 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2124 "by server %s\n", task->tk_pid, __func__,
2125 (unsigned int)clnt->cl_prog,
2126 (unsigned int)clnt->cl_vers,
2127 rcu_dereference(clnt->cl_xprt)->servername);
2128 error = -EPROTONOSUPPORT;
2129 goto out_err;
2130 case RPC_PROC_UNAVAIL:
2131 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2132 "version %u on server %s\n",
2133 task->tk_pid, __func__,
2134 rpc_proc_name(task),
2135 clnt->cl_prog, clnt->cl_vers,
2136 rcu_dereference(clnt->cl_xprt)->servername);
2137 error = -EOPNOTSUPP;
2138 goto out_err;
2139 case RPC_GARBAGE_ARGS:
2140 dprintk("RPC: %5u %s: server saw garbage\n",
2141 task->tk_pid, __func__);
2142 break; /* retry */
2143 default:
2144 dprintk("RPC: %5u %s: server accept status: %x\n",
2145 task->tk_pid, __func__, n);
2146 /* Also retry */
2147 }
2148
2149 out_garbage:
2150 clnt->cl_stats->rpcgarbage++;
2151 if (task->tk_garb_retry) {
2152 task->tk_garb_retry--;
2153 dprintk("RPC: %5u %s: retrying\n",
2154 task->tk_pid, __func__);
2155 task->tk_action = call_bind;
2156 out_retry:
2157 return ERR_PTR(-EAGAIN);
2158 }
2159 out_eio:
2160 error = -EIO;
2161 out_err:
2162 rpc_exit(task, error);
2163 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2164 __func__, error);
2165 return ERR_PTR(error);
2166 out_overflow:
2167 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2168 __func__);
2169 goto out_garbage;
2170 }
2171
2172 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2173 {
2174 }
2175
2176 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2177 {
2178 return 0;
2179 }
2180
2181 static struct rpc_procinfo rpcproc_null = {
2182 .p_encode = rpcproc_encode_null,
2183 .p_decode = rpcproc_decode_null,
2184 };
2185
2186 static int rpc_ping(struct rpc_clnt *clnt)
2187 {
2188 struct rpc_message msg = {
2189 .rpc_proc = &rpcproc_null,
2190 };
2191 int err;
2192 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2193 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2194 put_rpccred(msg.rpc_cred);
2195 return err;
2196 }
2197
2198 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2199 {
2200 struct rpc_message msg = {
2201 .rpc_proc = &rpcproc_null,
2202 .rpc_cred = cred,
2203 };
2204 struct rpc_task_setup task_setup_data = {
2205 .rpc_client = clnt,
2206 .rpc_message = &msg,
2207 .callback_ops = &rpc_default_ops,
2208 .flags = flags,
2209 };
2210 return rpc_run_task(&task_setup_data);
2211 }
2212 EXPORT_SYMBOL_GPL(rpc_call_null);
2213
2214 #ifdef RPC_DEBUG
2215 static void rpc_show_header(void)
2216 {
2217 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2218 "-timeout ---ops--\n");
2219 }
2220
2221 static void rpc_show_task(const struct rpc_clnt *clnt,
2222 const struct rpc_task *task)
2223 {
2224 const char *rpc_waitq = "none";
2225
2226 if (RPC_IS_QUEUED(task))
2227 rpc_waitq = rpc_qname(task->tk_waitqueue);
2228
2229 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2230 task->tk_pid, task->tk_flags, task->tk_status,
2231 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2232 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task),
2233 task->tk_action, rpc_waitq);
2234 }
2235
2236 void rpc_show_tasks(struct net *net)
2237 {
2238 struct rpc_clnt *clnt;
2239 struct rpc_task *task;
2240 int header = 0;
2241 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2242
2243 spin_lock(&sn->rpc_client_lock);
2244 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2245 spin_lock(&clnt->cl_lock);
2246 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2247 if (!header) {
2248 rpc_show_header();
2249 header++;
2250 }
2251 rpc_show_task(clnt, task);
2252 }
2253 spin_unlock(&clnt->cl_lock);
2254 }
2255 spin_unlock(&sn->rpc_client_lock);
2256 }
2257 #endif
Linux kernel - Deliverables
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