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ARM: ux500: Remove USB support when booting using ATAGs
[linux-2.6/btrfs-unstable.git] / net / sunrpc / clnt.c
blob77479606a9716e9526019ba5e5a0dfa4b7d010a2
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/addr.h>
37 #include <linux/sunrpc/rpc_pipe_fs.h>
38 #include <linux/sunrpc/metrics.h>
39 #include <linux/sunrpc/bc_xprt.h>
40 #include <trace/events/sunrpc.h>
41
42 #include "sunrpc.h"
43 #include "netns.h"
44
45 #ifdef RPC_DEBUG
46 # define RPCDBG_FACILITY RPCDBG_CALL
47 #endif
48
49 #define dprint_status(t) \
50 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
51 __func__, t->tk_status)
52
53 /*
54 * All RPC clients are linked into this list
55 */
56
57 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
58
59
60 static void call_start(struct rpc_task *task);
61 static void call_reserve(struct rpc_task *task);
62 static void call_reserveresult(struct rpc_task *task);
63 static void call_allocate(struct rpc_task *task);
64 static void call_decode(struct rpc_task *task);
65 static void call_bind(struct rpc_task *task);
66 static void call_bind_status(struct rpc_task *task);
67 static void call_transmit(struct rpc_task *task);
68 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
69 static void call_bc_transmit(struct rpc_task *task);
70 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
71 static void call_status(struct rpc_task *task);
72 static void call_transmit_status(struct rpc_task *task);
73 static void call_refresh(struct rpc_task *task);
74 static void call_refreshresult(struct rpc_task *task);
75 static void call_timeout(struct rpc_task *task);
76 static void call_connect(struct rpc_task *task);
77 static void call_connect_status(struct rpc_task *task);
78
79 static __be32 *rpc_encode_header(struct rpc_task *task);
80 static __be32 *rpc_verify_header(struct rpc_task *task);
81 static int rpc_ping(struct rpc_clnt *clnt);
82
83 static void rpc_register_client(struct rpc_clnt *clnt)
84 {
85 struct net *net = rpc_net_ns(clnt);
86 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
87
88 spin_lock(&sn->rpc_client_lock);
89 list_add(&clnt->cl_clients, &sn->all_clients);
90 spin_unlock(&sn->rpc_client_lock);
91 }
92
93 static void rpc_unregister_client(struct rpc_clnt *clnt)
94 {
95 struct net *net = rpc_net_ns(clnt);
96 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
97
98 spin_lock(&sn->rpc_client_lock);
99 list_del(&clnt->cl_clients);
100 spin_unlock(&sn->rpc_client_lock);
101 }
102
103 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
104 {
105 rpc_remove_client_dir(clnt);
106 }
107
108 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
109 {
110 struct net *net = rpc_net_ns(clnt);
111 struct super_block *pipefs_sb;
112
113 pipefs_sb = rpc_get_sb_net(net);
114 if (pipefs_sb) {
115 __rpc_clnt_remove_pipedir(clnt);
116 rpc_put_sb_net(net);
117 }
118 }
119
120 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
121 struct rpc_clnt *clnt)
122 {
123 static uint32_t clntid;
124 const char *dir_name = clnt->cl_program->pipe_dir_name;
125 char name[15];
126 struct dentry *dir, *dentry;
127
128 dir = rpc_d_lookup_sb(sb, dir_name);
129 if (dir == NULL) {
130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
131 return dir;
132 }
133 for (;;) {
134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
135 name[sizeof(name) - 1] = '\0';
136 dentry = rpc_create_client_dir(dir, name, clnt);
137 if (!IS_ERR(dentry))
138 break;
139 if (dentry == ERR_PTR(-EEXIST))
140 continue;
141 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
142 " %s/%s, error %ld\n",
143 dir_name, name, PTR_ERR(dentry));
144 break;
145 }
146 dput(dir);
147 return dentry;
148 }
149
150 static int
151 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
152 {
153 struct dentry *dentry;
154
155 if (clnt->cl_program->pipe_dir_name != NULL) {
156 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
157 if (IS_ERR(dentry))
158 return PTR_ERR(dentry);
159 }
160 return 0;
161 }
162
163 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
164 {
165 if (clnt->cl_program->pipe_dir_name == NULL)
166 return 1;
167
168 switch (event) {
169 case RPC_PIPEFS_MOUNT:
170 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
171 return 1;
172 if (atomic_read(&clnt->cl_count) == 0)
173 return 1;
174 break;
175 case RPC_PIPEFS_UMOUNT:
176 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
177 return 1;
178 break;
179 }
180 return 0;
181 }
182
183 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
184 struct super_block *sb)
185 {
186 struct dentry *dentry;
187 int err = 0;
188
189 switch (event) {
190 case RPC_PIPEFS_MOUNT:
191 dentry = rpc_setup_pipedir_sb(sb, clnt);
192 if (!dentry)
193 return -ENOENT;
194 if (IS_ERR(dentry))
195 return PTR_ERR(dentry);
196 break;
197 case RPC_PIPEFS_UMOUNT:
198 __rpc_clnt_remove_pipedir(clnt);
199 break;
200 default:
201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
202 return -ENOTSUPP;
203 }
204 return err;
205 }
206
207 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
208 struct super_block *sb)
209 {
210 int error = 0;
211
212 for (;; clnt = clnt->cl_parent) {
213 if (!rpc_clnt_skip_event(clnt, event))
214 error = __rpc_clnt_handle_event(clnt, event, sb);
215 if (error || clnt == clnt->cl_parent)
216 break;
217 }
218 return error;
219 }
220
221 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
222 {
223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
224 struct rpc_clnt *clnt;
225
226 spin_lock(&sn->rpc_client_lock);
227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
228 if (rpc_clnt_skip_event(clnt, event))
229 continue;
230 spin_unlock(&sn->rpc_client_lock);
231 return clnt;
232 }
233 spin_unlock(&sn->rpc_client_lock);
234 return NULL;
235 }
236
237 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
238 void *ptr)
239 {
240 struct super_block *sb = ptr;
241 struct rpc_clnt *clnt;
242 int error = 0;
243
244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
245 error = __rpc_pipefs_event(clnt, event, sb);
246 if (error)
247 break;
248 }
249 return error;
250 }
251
252 static struct notifier_block rpc_clients_block = {
253 .notifier_call = rpc_pipefs_event,
254 .priority = SUNRPC_PIPEFS_RPC_PRIO,
255 };
256
257 int rpc_clients_notifier_register(void)
258 {
259 return rpc_pipefs_notifier_register(&rpc_clients_block);
260 }
261
262 void rpc_clients_notifier_unregister(void)
263 {
264 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
265 }
266
267 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
268 {
269 clnt->cl_nodelen = strlen(nodename);
270 if (clnt->cl_nodelen > UNX_MAXNODENAME)
271 clnt->cl_nodelen = UNX_MAXNODENAME;
272 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen);
273 }
274
275 static int rpc_client_register(const struct rpc_create_args *args,
276 struct rpc_clnt *clnt)
277 {
278 struct rpc_auth_create_args auth_args = {
279 .pseudoflavor = args->authflavor,
280 .target_name = args->client_name,
281 };
282 struct rpc_auth *auth;
283 struct net *net = rpc_net_ns(clnt);
284 struct super_block *pipefs_sb;
285 int err;
286
287 pipefs_sb = rpc_get_sb_net(net);
288 if (pipefs_sb) {
289 err = rpc_setup_pipedir(pipefs_sb, clnt);
290 if (err)
291 goto out;
292 }
293
294 rpc_register_client(clnt);
295 if (pipefs_sb)
296 rpc_put_sb_net(net);
297
298 auth = rpcauth_create(&auth_args, clnt);
299 if (IS_ERR(auth)) {
300 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
301 args->authflavor);
302 err = PTR_ERR(auth);
303 goto err_auth;
304 }
305 return 0;
306 err_auth:
307 pipefs_sb = rpc_get_sb_net(net);
308 rpc_unregister_client(clnt);
309 __rpc_clnt_remove_pipedir(clnt);
310 out:
311 if (pipefs_sb)
312 rpc_put_sb_net(net);
313 return err;
314 }
315
316 static DEFINE_IDA(rpc_clids);
317
318 static int rpc_alloc_clid(struct rpc_clnt *clnt)
319 {
320 int clid;
321
322 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
323 if (clid < 0)
324 return clid;
325 clnt->cl_clid = clid;
326 return 0;
327 }
328
329 static void rpc_free_clid(struct rpc_clnt *clnt)
330 {
331 ida_simple_remove(&rpc_clids, clnt->cl_clid);
332 }
333
334 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
335 struct rpc_xprt *xprt,
336 struct rpc_clnt *parent)
337 {
338 const struct rpc_program *program = args->program;
339 const struct rpc_version *version;
340 struct rpc_clnt *clnt = NULL;
341 int err;
342
343 /* sanity check the name before trying to print it */
344 dprintk("RPC: creating %s client for %s (xprt %p)\n",
345 program->name, args->servername, xprt);
346
347 err = rpciod_up();
348 if (err)
349 goto out_no_rpciod;
350
351 err = -EINVAL;
352 if (args->version >= program->nrvers)
353 goto out_err;
354 version = program->version[args->version];
355 if (version == NULL)
356 goto out_err;
357
358 err = -ENOMEM;
359 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
360 if (!clnt)
361 goto out_err;
362 clnt->cl_parent = parent ? : clnt;
363
364 err = rpc_alloc_clid(clnt);
365 if (err)
366 goto out_no_clid;
367
368 rcu_assign_pointer(clnt->cl_xprt, xprt);
369 clnt->cl_procinfo = version->procs;
370 clnt->cl_maxproc = version->nrprocs;
371 clnt->cl_prog = args->prognumber ? : program->number;
372 clnt->cl_vers = version->number;
373 clnt->cl_stats = program->stats;
374 clnt->cl_metrics = rpc_alloc_iostats(clnt);
375 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
376 err = -ENOMEM;
377 if (clnt->cl_metrics == NULL)
378 goto out_no_stats;
379 clnt->cl_program = program;
380 INIT_LIST_HEAD(&clnt->cl_tasks);
381 spin_lock_init(&clnt->cl_lock);
382
383 if (!xprt_bound(xprt))
384 clnt->cl_autobind = 1;
385
386 clnt->cl_timeout = xprt->timeout;
387 if (args->timeout != NULL) {
388 memcpy(&clnt->cl_timeout_default, args->timeout,
389 sizeof(clnt->cl_timeout_default));
390 clnt->cl_timeout = &clnt->cl_timeout_default;
391 }
392
393 clnt->cl_rtt = &clnt->cl_rtt_default;
394 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
395
396 atomic_set(&clnt->cl_count, 1);
397
398 /* save the nodename */
399 rpc_clnt_set_nodename(clnt, utsname()->nodename);
400
401 err = rpc_client_register(args, clnt);
402 if (err)
403 goto out_no_path;
404 if (parent)
405 atomic_inc(&parent->cl_count);
406 return clnt;
407
408 out_no_path:
409 rpc_free_iostats(clnt->cl_metrics);
410 out_no_stats:
411 rpc_free_clid(clnt);
412 out_no_clid:
413 kfree(clnt);
414 out_err:
415 rpciod_down();
416 out_no_rpciod:
417 xprt_put(xprt);
418 return ERR_PTR(err);
419 }
420
421 /**
422 * rpc_create - create an RPC client and transport with one call
423 * @args: rpc_clnt create argument structure
424 *
425 * Creates and initializes an RPC transport and an RPC client.
426 *
427 * It can ping the server in order to determine if it is up, and to see if
428 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
429 * this behavior so asynchronous tasks can also use rpc_create.
430 */
431 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
432 {
433 struct rpc_xprt *xprt;
434 struct rpc_clnt *clnt;
435 struct xprt_create xprtargs = {
436 .net = args->net,
437 .ident = args->protocol,
438 .srcaddr = args->saddress,
439 .dstaddr = args->address,
440 .addrlen = args->addrsize,
441 .servername = args->servername,
442 .bc_xprt = args->bc_xprt,
443 };
444 char servername[48];
445
446 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
447 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
448 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
449 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
450 /*
451 * If the caller chooses not to specify a hostname, whip
452 * up a string representation of the passed-in address.
453 */
454 if (xprtargs.servername == NULL) {
455 struct sockaddr_un *sun =
456 (struct sockaddr_un *)args->address;
457 struct sockaddr_in *sin =
458 (struct sockaddr_in *)args->address;
459 struct sockaddr_in6 *sin6 =
460 (struct sockaddr_in6 *)args->address;
461
462 servername[0] = '\0';
463 switch (args->address->sa_family) {
464 case AF_LOCAL:
465 snprintf(servername, sizeof(servername), "%s",
466 sun->sun_path);
467 break;
468 case AF_INET:
469 snprintf(servername, sizeof(servername), "%pI4",
470 &sin->sin_addr.s_addr);
471 break;
472 case AF_INET6:
473 snprintf(servername, sizeof(servername), "%pI6",
474 &sin6->sin6_addr);
475 break;
476 default:
477 /* caller wants default server name, but
478 * address family isn't recognized. */
479 return ERR_PTR(-EINVAL);
480 }
481 xprtargs.servername = servername;
482 }
483
484 xprt = xprt_create_transport(&xprtargs);
485 if (IS_ERR(xprt))
486 return (struct rpc_clnt *)xprt;
487
488 /*
489 * By default, kernel RPC client connects from a reserved port.
490 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
491 * but it is always enabled for rpciod, which handles the connect
492 * operation.
493 */
494 xprt->resvport = 1;
495 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
496 xprt->resvport = 0;
497
498 clnt = rpc_new_client(args, xprt, NULL);
499 if (IS_ERR(clnt))
500 return clnt;
501
502 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
503 int err = rpc_ping(clnt);
504 if (err != 0) {
505 rpc_shutdown_client(clnt);
506 return ERR_PTR(err);
507 }
508 }
509
510 clnt->cl_softrtry = 1;
511 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
512 clnt->cl_softrtry = 0;
513
514 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
515 clnt->cl_autobind = 1;
516 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
517 clnt->cl_discrtry = 1;
518 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
519 clnt->cl_chatty = 1;
520
521 return clnt;
522 }
523 EXPORT_SYMBOL_GPL(rpc_create);
524
525 /*
526 * This function clones the RPC client structure. It allows us to share the
527 * same transport while varying parameters such as the authentication
528 * flavour.
529 */
530 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
531 struct rpc_clnt *clnt)
532 {
533 struct rpc_xprt *xprt;
534 struct rpc_clnt *new;
535 int err;
536
537 err = -ENOMEM;
538 rcu_read_lock();
539 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
540 rcu_read_unlock();
541 if (xprt == NULL)
542 goto out_err;
543 args->servername = xprt->servername;
544
545 new = rpc_new_client(args, xprt, clnt);
546 if (IS_ERR(new)) {
547 err = PTR_ERR(new);
548 goto out_err;
549 }
550
551 /* Turn off autobind on clones */
552 new->cl_autobind = 0;
553 new->cl_softrtry = clnt->cl_softrtry;
554 new->cl_discrtry = clnt->cl_discrtry;
555 new->cl_chatty = clnt->cl_chatty;
556 return new;
557
558 out_err:
559 dprintk("RPC: %s: returned error %d\n", __func__, err);
560 return ERR_PTR(err);
561 }
562
563 /**
564 * rpc_clone_client - Clone an RPC client structure
565 *
566 * @clnt: RPC client whose parameters are copied
567 *
568 * Returns a fresh RPC client or an ERR_PTR.
569 */
570 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
571 {
572 struct rpc_create_args args = {
573 .program = clnt->cl_program,
574 .prognumber = clnt->cl_prog,
575 .version = clnt->cl_vers,
576 .authflavor = clnt->cl_auth->au_flavor,
577 };
578 return __rpc_clone_client(&args, clnt);
579 }
580 EXPORT_SYMBOL_GPL(rpc_clone_client);
581
582 /**
583 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
584 *
585 * @clnt: RPC client whose parameters are copied
586 * @flavor: security flavor for new client
587 *
588 * Returns a fresh RPC client or an ERR_PTR.
589 */
590 struct rpc_clnt *
591 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
592 {
593 struct rpc_create_args args = {
594 .program = clnt->cl_program,
595 .prognumber = clnt->cl_prog,
596 .version = clnt->cl_vers,
597 .authflavor = flavor,
598 };
599 return __rpc_clone_client(&args, clnt);
600 }
601 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
602
603 /*
604 * Kill all tasks for the given client.
605 * XXX: kill their descendants as well?
606 */
607 void rpc_killall_tasks(struct rpc_clnt *clnt)
608 {
609 struct rpc_task *rovr;
610
611
612 if (list_empty(&clnt->cl_tasks))
613 return;
614 dprintk("RPC: killing all tasks for client %p\n", clnt);
615 /*
616 * Spin lock all_tasks to prevent changes...
617 */
618 spin_lock(&clnt->cl_lock);
619 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
620 if (!RPC_IS_ACTIVATED(rovr))
621 continue;
622 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
623 rovr->tk_flags |= RPC_TASK_KILLED;
624 rpc_exit(rovr, -EIO);
625 if (RPC_IS_QUEUED(rovr))
626 rpc_wake_up_queued_task(rovr->tk_waitqueue,
627 rovr);
628 }
629 }
630 spin_unlock(&clnt->cl_lock);
631 }
632 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
633
634 /*
635 * Properly shut down an RPC client, terminating all outstanding
636 * requests.
637 */
638 void rpc_shutdown_client(struct rpc_clnt *clnt)
639 {
640 might_sleep();
641
642 dprintk_rcu("RPC: shutting down %s client for %s\n",
643 clnt->cl_program->name,
644 rcu_dereference(clnt->cl_xprt)->servername);
645
646 while (!list_empty(&clnt->cl_tasks)) {
647 rpc_killall_tasks(clnt);
648 wait_event_timeout(destroy_wait,
649 list_empty(&clnt->cl_tasks), 1*HZ);
650 }
651
652 rpc_release_client(clnt);
653 }
654 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
655
656 /*
657 * Free an RPC client
658 */
659 static void
660 rpc_free_client(struct rpc_clnt *clnt)
661 {
662 dprintk_rcu("RPC: destroying %s client for %s\n",
663 clnt->cl_program->name,
664 rcu_dereference(clnt->cl_xprt)->servername);
665 if (clnt->cl_parent != clnt)
666 rpc_release_client(clnt->cl_parent);
667 rpc_clnt_remove_pipedir(clnt);
668 rpc_unregister_client(clnt);
669 rpc_free_iostats(clnt->cl_metrics);
670 clnt->cl_metrics = NULL;
671 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
672 rpciod_down();
673 rpc_free_clid(clnt);
674 kfree(clnt);
675 }
676
677 /*
678 * Free an RPC client
679 */
680 static void
681 rpc_free_auth(struct rpc_clnt *clnt)
682 {
683 if (clnt->cl_auth == NULL) {
684 rpc_free_client(clnt);
685 return;
686 }
687
688 /*
689 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
690 * release remaining GSS contexts. This mechanism ensures
691 * that it can do so safely.
692 */
693 atomic_inc(&clnt->cl_count);
694 rpcauth_release(clnt->cl_auth);
695 clnt->cl_auth = NULL;
696 if (atomic_dec_and_test(&clnt->cl_count))
697 rpc_free_client(clnt);
698 }
699
700 /*
701 * Release reference to the RPC client
702 */
703 void
704 rpc_release_client(struct rpc_clnt *clnt)
705 {
706 dprintk("RPC: rpc_release_client(%p)\n", clnt);
707
708 if (list_empty(&clnt->cl_tasks))
709 wake_up(&destroy_wait);
710 if (atomic_dec_and_test(&clnt->cl_count))
711 rpc_free_auth(clnt);
712 }
713 EXPORT_SYMBOL_GPL(rpc_release_client);
714
715 /**
716 * rpc_bind_new_program - bind a new RPC program to an existing client
717 * @old: old rpc_client
718 * @program: rpc program to set
719 * @vers: rpc program version
720 *
721 * Clones the rpc client and sets up a new RPC program. This is mainly
722 * of use for enabling different RPC programs to share the same transport.
723 * The Sun NFSv2/v3 ACL protocol can do this.
724 */
725 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
726 const struct rpc_program *program,
727 u32 vers)
728 {
729 struct rpc_create_args args = {
730 .program = program,
731 .prognumber = program->number,
732 .version = vers,
733 .authflavor = old->cl_auth->au_flavor,
734 };
735 struct rpc_clnt *clnt;
736 int err;
737
738 clnt = __rpc_clone_client(&args, old);
739 if (IS_ERR(clnt))
740 goto out;
741 err = rpc_ping(clnt);
742 if (err != 0) {
743 rpc_shutdown_client(clnt);
744 clnt = ERR_PTR(err);
745 }
746 out:
747 return clnt;
748 }
749 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
750
751 void rpc_task_release_client(struct rpc_task *task)
752 {
753 struct rpc_clnt *clnt = task->tk_client;
754
755 if (clnt != NULL) {
756 /* Remove from client task list */
757 spin_lock(&clnt->cl_lock);
758 list_del(&task->tk_task);
759 spin_unlock(&clnt->cl_lock);
760 task->tk_client = NULL;
761
762 rpc_release_client(clnt);
763 }
764 }
765
766 static
767 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
768 {
769 if (clnt != NULL) {
770 rpc_task_release_client(task);
771 task->tk_client = clnt;
772 atomic_inc(&clnt->cl_count);
773 if (clnt->cl_softrtry)
774 task->tk_flags |= RPC_TASK_SOFT;
775 if (sk_memalloc_socks()) {
776 struct rpc_xprt *xprt;
777
778 rcu_read_lock();
779 xprt = rcu_dereference(clnt->cl_xprt);
780 if (xprt->swapper)
781 task->tk_flags |= RPC_TASK_SWAPPER;
782 rcu_read_unlock();
783 }
784 /* Add to the client's list of all tasks */
785 spin_lock(&clnt->cl_lock);
786 list_add_tail(&task->tk_task, &clnt->cl_tasks);
787 spin_unlock(&clnt->cl_lock);
788 }
789 }
790
791 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
792 {
793 rpc_task_release_client(task);
794 rpc_task_set_client(task, clnt);
795 }
796 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
797
798
799 static void
800 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
801 {
802 if (msg != NULL) {
803 task->tk_msg.rpc_proc = msg->rpc_proc;
804 task->tk_msg.rpc_argp = msg->rpc_argp;
805 task->tk_msg.rpc_resp = msg->rpc_resp;
806 if (msg->rpc_cred != NULL)
807 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
808 }
809 }
810
811 /*
812 * Default callback for async RPC calls
813 */
814 static void
815 rpc_default_callback(struct rpc_task *task, void *data)
816 {
817 }
818
819 static const struct rpc_call_ops rpc_default_ops = {
820 .rpc_call_done = rpc_default_callback,
821 };
822
823 /**
824 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
825 * @task_setup_data: pointer to task initialisation data
826 */
827 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
828 {
829 struct rpc_task *task;
830
831 task = rpc_new_task(task_setup_data);
832 if (IS_ERR(task))
833 goto out;
834
835 rpc_task_set_client(task, task_setup_data->rpc_client);
836 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
837
838 if (task->tk_action == NULL)
839 rpc_call_start(task);
840
841 atomic_inc(&task->tk_count);
842 rpc_execute(task);
843 out:
844 return task;
845 }
846 EXPORT_SYMBOL_GPL(rpc_run_task);
847
848 /**
849 * rpc_call_sync - Perform a synchronous RPC call
850 * @clnt: pointer to RPC client
851 * @msg: RPC call parameters
852 * @flags: RPC call flags
853 */
854 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
855 {
856 struct rpc_task *task;
857 struct rpc_task_setup task_setup_data = {
858 .rpc_client = clnt,
859 .rpc_message = msg,
860 .callback_ops = &rpc_default_ops,
861 .flags = flags,
862 };
863 int status;
864
865 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
866 if (flags & RPC_TASK_ASYNC) {
867 rpc_release_calldata(task_setup_data.callback_ops,
868 task_setup_data.callback_data);
869 return -EINVAL;
870 }
871
872 task = rpc_run_task(&task_setup_data);
873 if (IS_ERR(task))
874 return PTR_ERR(task);
875 status = task->tk_status;
876 rpc_put_task(task);
877 return status;
878 }
879 EXPORT_SYMBOL_GPL(rpc_call_sync);
880
881 /**
882 * rpc_call_async - Perform an asynchronous RPC call
883 * @clnt: pointer to RPC client
884 * @msg: RPC call parameters
885 * @flags: RPC call flags
886 * @tk_ops: RPC call ops
887 * @data: user call data
888 */
889 int
890 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
891 const struct rpc_call_ops *tk_ops, void *data)
892 {
893 struct rpc_task *task;
894 struct rpc_task_setup task_setup_data = {
895 .rpc_client = clnt,
896 .rpc_message = msg,
897 .callback_ops = tk_ops,
898 .callback_data = data,
899 .flags = flags|RPC_TASK_ASYNC,
900 };
901
902 task = rpc_run_task(&task_setup_data);
903 if (IS_ERR(task))
904 return PTR_ERR(task);
905 rpc_put_task(task);
906 return 0;
907 }
908 EXPORT_SYMBOL_GPL(rpc_call_async);
909
910 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
911 /**
912 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
913 * rpc_execute against it
914 * @req: RPC request
915 * @tk_ops: RPC call ops
916 */
917 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
918 const struct rpc_call_ops *tk_ops)
919 {
920 struct rpc_task *task;
921 struct xdr_buf *xbufp = &req->rq_snd_buf;
922 struct rpc_task_setup task_setup_data = {
923 .callback_ops = tk_ops,
924 };
925
926 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
927 /*
928 * Create an rpc_task to send the data
929 */
930 task = rpc_new_task(&task_setup_data);
931 if (IS_ERR(task)) {
932 xprt_free_bc_request(req);
933 goto out;
934 }
935 task->tk_rqstp = req;
936
937 /*
938 * Set up the xdr_buf length.
939 * This also indicates that the buffer is XDR encoded already.
940 */
941 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
942 xbufp->tail[0].iov_len;
943
944 task->tk_action = call_bc_transmit;
945 atomic_inc(&task->tk_count);
946 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
947 rpc_execute(task);
948
949 out:
950 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
951 return task;
952 }
953 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
954
955 void
956 rpc_call_start(struct rpc_task *task)
957 {
958 task->tk_action = call_start;
959 }
960 EXPORT_SYMBOL_GPL(rpc_call_start);
961
962 /**
963 * rpc_peeraddr - extract remote peer address from clnt's xprt
964 * @clnt: RPC client structure
965 * @buf: target buffer
966 * @bufsize: length of target buffer
967 *
968 * Returns the number of bytes that are actually in the stored address.
969 */
970 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
971 {
972 size_t bytes;
973 struct rpc_xprt *xprt;
974
975 rcu_read_lock();
976 xprt = rcu_dereference(clnt->cl_xprt);
977
978 bytes = xprt->addrlen;
979 if (bytes > bufsize)
980 bytes = bufsize;
981 memcpy(buf, &xprt->addr, bytes);
982 rcu_read_unlock();
983
984 return bytes;
985 }
986 EXPORT_SYMBOL_GPL(rpc_peeraddr);
987
988 /**
989 * rpc_peeraddr2str - return remote peer address in printable format
990 * @clnt: RPC client structure
991 * @format: address format
992 *
993 * NB: the lifetime of the memory referenced by the returned pointer is
994 * the same as the rpc_xprt itself. As long as the caller uses this
995 * pointer, it must hold the RCU read lock.
996 */
997 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
998 enum rpc_display_format_t format)
999 {
1000 struct rpc_xprt *xprt;
1001
1002 xprt = rcu_dereference(clnt->cl_xprt);
1003
1004 if (xprt->address_strings[format] != NULL)
1005 return xprt->address_strings[format];
1006 else
1007 return "unprintable";
1008 }
1009 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1010
1011 static const struct sockaddr_in rpc_inaddr_loopback = {
1012 .sin_family = AF_INET,
1013 .sin_addr.s_addr = htonl(INADDR_ANY),
1014 };
1015
1016 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1017 .sin6_family = AF_INET6,
1018 .sin6_addr = IN6ADDR_ANY_INIT,
1019 };
1020
1021 /*
1022 * Try a getsockname() on a connected datagram socket. Using a
1023 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1024 * This conserves the ephemeral port number space.
1025 *
1026 * Returns zero and fills in "buf" if successful; otherwise, a
1027 * negative errno is returned.
1028 */
1029 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1030 struct sockaddr *buf, int buflen)
1031 {
1032 struct socket *sock;
1033 int err;
1034
1035 err = __sock_create(net, sap->sa_family,
1036 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1037 if (err < 0) {
1038 dprintk("RPC: can't create UDP socket (%d)\n", err);
1039 goto out;
1040 }
1041
1042 switch (sap->sa_family) {
1043 case AF_INET:
1044 err = kernel_bind(sock,
1045 (struct sockaddr *)&rpc_inaddr_loopback,
1046 sizeof(rpc_inaddr_loopback));
1047 break;
1048 case AF_INET6:
1049 err = kernel_bind(sock,
1050 (struct sockaddr *)&rpc_in6addr_loopback,
1051 sizeof(rpc_in6addr_loopback));
1052 break;
1053 default:
1054 err = -EAFNOSUPPORT;
1055 goto out;
1056 }
1057 if (err < 0) {
1058 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1059 goto out_release;
1060 }
1061
1062 err = kernel_connect(sock, sap, salen, 0);
1063 if (err < 0) {
1064 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1065 goto out_release;
1066 }
1067
1068 err = kernel_getsockname(sock, buf, &buflen);
1069 if (err < 0) {
1070 dprintk("RPC: getsockname failed (%d)\n", err);
1071 goto out_release;
1072 }
1073
1074 err = 0;
1075 if (buf->sa_family == AF_INET6) {
1076 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1077 sin6->sin6_scope_id = 0;
1078 }
1079 dprintk("RPC: %s succeeded\n", __func__);
1080
1081 out_release:
1082 sock_release(sock);
1083 out:
1084 return err;
1085 }
1086
1087 /*
1088 * Scraping a connected socket failed, so we don't have a useable
1089 * local address. Fallback: generate an address that will prevent
1090 * the server from calling us back.
1091 *
1092 * Returns zero and fills in "buf" if successful; otherwise, a
1093 * negative errno is returned.
1094 */
1095 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1096 {
1097 switch (family) {
1098 case AF_INET:
1099 if (buflen < sizeof(rpc_inaddr_loopback))
1100 return -EINVAL;
1101 memcpy(buf, &rpc_inaddr_loopback,
1102 sizeof(rpc_inaddr_loopback));
1103 break;
1104 case AF_INET6:
1105 if (buflen < sizeof(rpc_in6addr_loopback))
1106 return -EINVAL;
1107 memcpy(buf, &rpc_in6addr_loopback,
1108 sizeof(rpc_in6addr_loopback));
1109 default:
1110 dprintk("RPC: %s: address family not supported\n",
1111 __func__);
1112 return -EAFNOSUPPORT;
1113 }
1114 dprintk("RPC: %s: succeeded\n", __func__);
1115 return 0;
1116 }
1117
1118 /**
1119 * rpc_localaddr - discover local endpoint address for an RPC client
1120 * @clnt: RPC client structure
1121 * @buf: target buffer
1122 * @buflen: size of target buffer, in bytes
1123 *
1124 * Returns zero and fills in "buf" and "buflen" if successful;
1125 * otherwise, a negative errno is returned.
1126 *
1127 * This works even if the underlying transport is not currently connected,
1128 * or if the upper layer never previously provided a source address.
1129 *
1130 * The result of this function call is transient: multiple calls in
1131 * succession may give different results, depending on how local
1132 * networking configuration changes over time.
1133 */
1134 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1135 {
1136 struct sockaddr_storage address;
1137 struct sockaddr *sap = (struct sockaddr *)&address;
1138 struct rpc_xprt *xprt;
1139 struct net *net;
1140 size_t salen;
1141 int err;
1142
1143 rcu_read_lock();
1144 xprt = rcu_dereference(clnt->cl_xprt);
1145 salen = xprt->addrlen;
1146 memcpy(sap, &xprt->addr, salen);
1147 net = get_net(xprt->xprt_net);
1148 rcu_read_unlock();
1149
1150 rpc_set_port(sap, 0);
1151 err = rpc_sockname(net, sap, salen, buf, buflen);
1152 put_net(net);
1153 if (err != 0)
1154 /* Couldn't discover local address, return ANYADDR */
1155 return rpc_anyaddr(sap->sa_family, buf, buflen);
1156 return 0;
1157 }
1158 EXPORT_SYMBOL_GPL(rpc_localaddr);
1159
1160 void
1161 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1162 {
1163 struct rpc_xprt *xprt;
1164
1165 rcu_read_lock();
1166 xprt = rcu_dereference(clnt->cl_xprt);
1167 if (xprt->ops->set_buffer_size)
1168 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1169 rcu_read_unlock();
1170 }
1171 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1172
1173 /**
1174 * rpc_protocol - Get transport protocol number for an RPC client
1175 * @clnt: RPC client to query
1176 *
1177 */
1178 int rpc_protocol(struct rpc_clnt *clnt)
1179 {
1180 int protocol;
1181
1182 rcu_read_lock();
1183 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1184 rcu_read_unlock();
1185 return protocol;
1186 }
1187 EXPORT_SYMBOL_GPL(rpc_protocol);
1188
1189 /**
1190 * rpc_net_ns - Get the network namespace for this RPC client
1191 * @clnt: RPC client to query
1192 *
1193 */
1194 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1195 {
1196 struct net *ret;
1197
1198 rcu_read_lock();
1199 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1200 rcu_read_unlock();
1201 return ret;
1202 }
1203 EXPORT_SYMBOL_GPL(rpc_net_ns);
1204
1205 /**
1206 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1207 * @clnt: RPC client to query
1208 *
1209 * For stream transports, this is one RPC record fragment (see RFC
1210 * 1831), as we don't support multi-record requests yet. For datagram
1211 * transports, this is the size of an IP packet minus the IP, UDP, and
1212 * RPC header sizes.
1213 */
1214 size_t rpc_max_payload(struct rpc_clnt *clnt)
1215 {
1216 size_t ret;
1217
1218 rcu_read_lock();
1219 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1220 rcu_read_unlock();
1221 return ret;
1222 }
1223 EXPORT_SYMBOL_GPL(rpc_max_payload);
1224
1225 /**
1226 * rpc_get_timeout - Get timeout for transport in units of HZ
1227 * @clnt: RPC client to query
1228 */
1229 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1230 {
1231 unsigned long ret;
1232
1233 rcu_read_lock();
1234 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1235 rcu_read_unlock();
1236 return ret;
1237 }
1238 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1239
1240 /**
1241 * rpc_force_rebind - force transport to check that remote port is unchanged
1242 * @clnt: client to rebind
1243 *
1244 */
1245 void rpc_force_rebind(struct rpc_clnt *clnt)
1246 {
1247 if (clnt->cl_autobind) {
1248 rcu_read_lock();
1249 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1250 rcu_read_unlock();
1251 }
1252 }
1253 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1254
1255 /*
1256 * Restart an (async) RPC call from the call_prepare state.
1257 * Usually called from within the exit handler.
1258 */
1259 int
1260 rpc_restart_call_prepare(struct rpc_task *task)
1261 {
1262 if (RPC_ASSASSINATED(task))
1263 return 0;
1264 task->tk_action = call_start;
1265 if (task->tk_ops->rpc_call_prepare != NULL)
1266 task->tk_action = rpc_prepare_task;
1267 return 1;
1268 }
1269 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1270
1271 /*
1272 * Restart an (async) RPC call. Usually called from within the
1273 * exit handler.
1274 */
1275 int
1276 rpc_restart_call(struct rpc_task *task)
1277 {
1278 if (RPC_ASSASSINATED(task))
1279 return 0;
1280 task->tk_action = call_start;
1281 return 1;
1282 }
1283 EXPORT_SYMBOL_GPL(rpc_restart_call);
1284
1285 #ifdef RPC_DEBUG
1286 static const char *rpc_proc_name(const struct rpc_task *task)
1287 {
1288 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1289
1290 if (proc) {
1291 if (proc->p_name)
1292 return proc->p_name;
1293 else
1294 return "NULL";
1295 } else
1296 return "no proc";
1297 }
1298 #endif
1299
1300 /*
1301 * 0. Initial state
1302 *
1303 * Other FSM states can be visited zero or more times, but
1304 * this state is visited exactly once for each RPC.
1305 */
1306 static void
1307 call_start(struct rpc_task *task)
1308 {
1309 struct rpc_clnt *clnt = task->tk_client;
1310
1311 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1312 clnt->cl_program->name, clnt->cl_vers,
1313 rpc_proc_name(task),
1314 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1315
1316 /* Increment call count */
1317 task->tk_msg.rpc_proc->p_count++;
1318 clnt->cl_stats->rpccnt++;
1319 task->tk_action = call_reserve;
1320 }
1321
1322 /*
1323 * 1. Reserve an RPC call slot
1324 */
1325 static void
1326 call_reserve(struct rpc_task *task)
1327 {
1328 dprint_status(task);
1329
1330 task->tk_status = 0;
1331 task->tk_action = call_reserveresult;
1332 xprt_reserve(task);
1333 }
1334
1335 static void call_retry_reserve(struct rpc_task *task);
1336
1337 /*
1338 * 1b. Grok the result of xprt_reserve()
1339 */
1340 static void
1341 call_reserveresult(struct rpc_task *task)
1342 {
1343 int status = task->tk_status;
1344
1345 dprint_status(task);
1346
1347 /*
1348 * After a call to xprt_reserve(), we must have either
1349 * a request slot or else an error status.
1350 */
1351 task->tk_status = 0;
1352 if (status >= 0) {
1353 if (task->tk_rqstp) {
1354 task->tk_action = call_refresh;
1355 return;
1356 }
1357
1358 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1359 __func__, status);
1360 rpc_exit(task, -EIO);
1361 return;
1362 }
1363
1364 /*
1365 * Even though there was an error, we may have acquired
1366 * a request slot somehow. Make sure not to leak it.
1367 */
1368 if (task->tk_rqstp) {
1369 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1370 __func__, status);
1371 xprt_release(task);
1372 }
1373
1374 switch (status) {
1375 case -ENOMEM:
1376 rpc_delay(task, HZ >> 2);
1377 case -EAGAIN: /* woken up; retry */
1378 task->tk_action = call_retry_reserve;
1379 return;
1380 case -EIO: /* probably a shutdown */
1381 break;
1382 default:
1383 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1384 __func__, status);
1385 break;
1386 }
1387 rpc_exit(task, status);
1388 }
1389
1390 /*
1391 * 1c. Retry reserving an RPC call slot
1392 */
1393 static void
1394 call_retry_reserve(struct rpc_task *task)
1395 {
1396 dprint_status(task);
1397
1398 task->tk_status = 0;
1399 task->tk_action = call_reserveresult;
1400 xprt_retry_reserve(task);
1401 }
1402
1403 /*
1404 * 2. Bind and/or refresh the credentials
1405 */
1406 static void
1407 call_refresh(struct rpc_task *task)
1408 {
1409 dprint_status(task);
1410
1411 task->tk_action = call_refreshresult;
1412 task->tk_status = 0;
1413 task->tk_client->cl_stats->rpcauthrefresh++;
1414 rpcauth_refreshcred(task);
1415 }
1416
1417 /*
1418 * 2a. Process the results of a credential refresh
1419 */
1420 static void
1421 call_refreshresult(struct rpc_task *task)
1422 {
1423 int status = task->tk_status;
1424
1425 dprint_status(task);
1426
1427 task->tk_status = 0;
1428 task->tk_action = call_refresh;
1429 switch (status) {
1430 case 0:
1431 if (rpcauth_uptodatecred(task))
1432 task->tk_action = call_allocate;
1433 return;
1434 case -ETIMEDOUT:
1435 rpc_delay(task, 3*HZ);
1436 case -EAGAIN:
1437 status = -EACCES;
1438 case -EKEYEXPIRED:
1439 if (!task->tk_cred_retry)
1440 break;
1441 task->tk_cred_retry--;
1442 dprintk("RPC: %5u %s: retry refresh creds\n",
1443 task->tk_pid, __func__);
1444 return;
1445 }
1446 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1447 task->tk_pid, __func__, status);
1448 rpc_exit(task, status);
1449 }
1450
1451 /*
1452 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1453 * (Note: buffer memory is freed in xprt_release).
1454 */
1455 static void
1456 call_allocate(struct rpc_task *task)
1457 {
1458 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1459 struct rpc_rqst *req = task->tk_rqstp;
1460 struct rpc_xprt *xprt = req->rq_xprt;
1461 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1462
1463 dprint_status(task);
1464
1465 task->tk_status = 0;
1466 task->tk_action = call_bind;
1467
1468 if (req->rq_buffer)
1469 return;
1470
1471 if (proc->p_proc != 0) {
1472 BUG_ON(proc->p_arglen == 0);
1473 if (proc->p_decode != NULL)
1474 BUG_ON(proc->p_replen == 0);
1475 }
1476
1477 /*
1478 * Calculate the size (in quads) of the RPC call
1479 * and reply headers, and convert both values
1480 * to byte sizes.
1481 */
1482 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1483 req->rq_callsize <<= 2;
1484 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1485 req->rq_rcvsize <<= 2;
1486
1487 req->rq_buffer = xprt->ops->buf_alloc(task,
1488 req->rq_callsize + req->rq_rcvsize);
1489 if (req->rq_buffer != NULL)
1490 return;
1491
1492 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1493
1494 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1495 task->tk_action = call_allocate;
1496 rpc_delay(task, HZ>>4);
1497 return;
1498 }
1499
1500 rpc_exit(task, -ERESTARTSYS);
1501 }
1502
1503 static inline int
1504 rpc_task_need_encode(struct rpc_task *task)
1505 {
1506 return task->tk_rqstp->rq_snd_buf.len == 0;
1507 }
1508
1509 static inline void
1510 rpc_task_force_reencode(struct rpc_task *task)
1511 {
1512 task->tk_rqstp->rq_snd_buf.len = 0;
1513 task->tk_rqstp->rq_bytes_sent = 0;
1514 }
1515
1516 static inline void
1517 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1518 {
1519 buf->head[0].iov_base = start;
1520 buf->head[0].iov_len = len;
1521 buf->tail[0].iov_len = 0;
1522 buf->page_len = 0;
1523 buf->flags = 0;
1524 buf->len = 0;
1525 buf->buflen = len;
1526 }
1527
1528 /*
1529 * 3. Encode arguments of an RPC call
1530 */
1531 static void
1532 rpc_xdr_encode(struct rpc_task *task)
1533 {
1534 struct rpc_rqst *req = task->tk_rqstp;
1535 kxdreproc_t encode;
1536 __be32 *p;
1537
1538 dprint_status(task);
1539
1540 rpc_xdr_buf_init(&req->rq_snd_buf,
1541 req->rq_buffer,
1542 req->rq_callsize);
1543 rpc_xdr_buf_init(&req->rq_rcv_buf,
1544 (char *)req->rq_buffer + req->rq_callsize,
1545 req->rq_rcvsize);
1546
1547 p = rpc_encode_header(task);
1548 if (p == NULL) {
1549 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1550 rpc_exit(task, -EIO);
1551 return;
1552 }
1553
1554 encode = task->tk_msg.rpc_proc->p_encode;
1555 if (encode == NULL)
1556 return;
1557
1558 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1559 task->tk_msg.rpc_argp);
1560 }
1561
1562 /*
1563 * 4. Get the server port number if not yet set
1564 */
1565 static void
1566 call_bind(struct rpc_task *task)
1567 {
1568 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1569
1570 dprint_status(task);
1571
1572 task->tk_action = call_connect;
1573 if (!xprt_bound(xprt)) {
1574 task->tk_action = call_bind_status;
1575 task->tk_timeout = xprt->bind_timeout;
1576 xprt->ops->rpcbind(task);
1577 }
1578 }
1579
1580 /*
1581 * 4a. Sort out bind result
1582 */
1583 static void
1584 call_bind_status(struct rpc_task *task)
1585 {
1586 int status = -EIO;
1587
1588 if (task->tk_status >= 0) {
1589 dprint_status(task);
1590 task->tk_status = 0;
1591 task->tk_action = call_connect;
1592 return;
1593 }
1594
1595 trace_rpc_bind_status(task);
1596 switch (task->tk_status) {
1597 case -ENOMEM:
1598 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1599 rpc_delay(task, HZ >> 2);
1600 goto retry_timeout;
1601 case -EACCES:
1602 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1603 "unavailable\n", task->tk_pid);
1604 /* fail immediately if this is an RPC ping */
1605 if (task->tk_msg.rpc_proc->p_proc == 0) {
1606 status = -EOPNOTSUPP;
1607 break;
1608 }
1609 if (task->tk_rebind_retry == 0)
1610 break;
1611 task->tk_rebind_retry--;
1612 rpc_delay(task, 3*HZ);
1613 goto retry_timeout;
1614 case -ETIMEDOUT:
1615 dprintk("RPC: %5u rpcbind request timed out\n",
1616 task->tk_pid);
1617 goto retry_timeout;
1618 case -EPFNOSUPPORT:
1619 /* server doesn't support any rpcbind version we know of */
1620 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1621 task->tk_pid);
1622 break;
1623 case -EPROTONOSUPPORT:
1624 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1625 task->tk_pid);
1626 task->tk_status = 0;
1627 task->tk_action = call_bind;
1628 return;
1629 case -ECONNREFUSED: /* connection problems */
1630 case -ECONNRESET:
1631 case -ENOTCONN:
1632 case -EHOSTDOWN:
1633 case -EHOSTUNREACH:
1634 case -ENETUNREACH:
1635 case -EPIPE:
1636 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1637 task->tk_pid, task->tk_status);
1638 if (!RPC_IS_SOFTCONN(task)) {
1639 rpc_delay(task, 5*HZ);
1640 goto retry_timeout;
1641 }
1642 status = task->tk_status;
1643 break;
1644 default:
1645 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1646 task->tk_pid, -task->tk_status);
1647 }
1648
1649 rpc_exit(task, status);
1650 return;
1651
1652 retry_timeout:
1653 task->tk_action = call_timeout;
1654 }
1655
1656 /*
1657 * 4b. Connect to the RPC server
1658 */
1659 static void
1660 call_connect(struct rpc_task *task)
1661 {
1662 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1663
1664 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1665 task->tk_pid, xprt,
1666 (xprt_connected(xprt) ? "is" : "is not"));
1667
1668 task->tk_action = call_transmit;
1669 if (!xprt_connected(xprt)) {
1670 task->tk_action = call_connect_status;
1671 if (task->tk_status < 0)
1672 return;
1673 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1674 rpc_exit(task, -ENOTCONN);
1675 return;
1676 }
1677 xprt_connect(task);
1678 }
1679 }
1680
1681 /*
1682 * 4c. Sort out connect result
1683 */
1684 static void
1685 call_connect_status(struct rpc_task *task)
1686 {
1687 struct rpc_clnt *clnt = task->tk_client;
1688 int status = task->tk_status;
1689
1690 dprint_status(task);
1691
1692 trace_rpc_connect_status(task, status);
1693 switch (status) {
1694 /* if soft mounted, test if we've timed out */
1695 case -ETIMEDOUT:
1696 task->tk_action = call_timeout;
1697 return;
1698 case -ECONNREFUSED:
1699 case -ECONNRESET:
1700 case -ENETUNREACH:
1701 if (RPC_IS_SOFTCONN(task))
1702 break;
1703 /* retry with existing socket, after a delay */
1704 case 0:
1705 case -EAGAIN:
1706 task->tk_status = 0;
1707 clnt->cl_stats->netreconn++;
1708 task->tk_action = call_transmit;
1709 return;
1710 }
1711 rpc_exit(task, status);
1712 }
1713
1714 /*
1715 * 5. Transmit the RPC request, and wait for reply
1716 */
1717 static void
1718 call_transmit(struct rpc_task *task)
1719 {
1720 dprint_status(task);
1721
1722 task->tk_action = call_status;
1723 if (task->tk_status < 0)
1724 return;
1725 task->tk_status = xprt_prepare_transmit(task);
1726 if (task->tk_status != 0)
1727 return;
1728 task->tk_action = call_transmit_status;
1729 /* Encode here so that rpcsec_gss can use correct sequence number. */
1730 if (rpc_task_need_encode(task)) {
1731 rpc_xdr_encode(task);
1732 /* Did the encode result in an error condition? */
1733 if (task->tk_status != 0) {
1734 /* Was the error nonfatal? */
1735 if (task->tk_status == -EAGAIN)
1736 rpc_delay(task, HZ >> 4);
1737 else
1738 rpc_exit(task, task->tk_status);
1739 return;
1740 }
1741 }
1742 xprt_transmit(task);
1743 if (task->tk_status < 0)
1744 return;
1745 /*
1746 * On success, ensure that we call xprt_end_transmit() before sleeping
1747 * in order to allow access to the socket to other RPC requests.
1748 */
1749 call_transmit_status(task);
1750 if (rpc_reply_expected(task))
1751 return;
1752 task->tk_action = rpc_exit_task;
1753 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1754 }
1755
1756 /*
1757 * 5a. Handle cleanup after a transmission
1758 */
1759 static void
1760 call_transmit_status(struct rpc_task *task)
1761 {
1762 task->tk_action = call_status;
1763
1764 /*
1765 * Common case: success. Force the compiler to put this
1766 * test first.
1767 */
1768 if (task->tk_status == 0) {
1769 xprt_end_transmit(task);
1770 rpc_task_force_reencode(task);
1771 return;
1772 }
1773
1774 switch (task->tk_status) {
1775 case -EAGAIN:
1776 break;
1777 default:
1778 dprint_status(task);
1779 xprt_end_transmit(task);
1780 rpc_task_force_reencode(task);
1781 break;
1782 /*
1783 * Special cases: if we've been waiting on the
1784 * socket's write_space() callback, or if the
1785 * socket just returned a connection error,
1786 * then hold onto the transport lock.
1787 */
1788 case -ECONNREFUSED:
1789 case -EHOSTDOWN:
1790 case -EHOSTUNREACH:
1791 case -ENETUNREACH:
1792 if (RPC_IS_SOFTCONN(task)) {
1793 xprt_end_transmit(task);
1794 rpc_exit(task, task->tk_status);
1795 break;
1796 }
1797 case -ECONNRESET:
1798 case -ENOTCONN:
1799 case -EPIPE:
1800 rpc_task_force_reencode(task);
1801 }
1802 }
1803
1804 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1805 /*
1806 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1807 * addition, disconnect on connectivity errors.
1808 */
1809 static void
1810 call_bc_transmit(struct rpc_task *task)
1811 {
1812 struct rpc_rqst *req = task->tk_rqstp;
1813
1814 task->tk_status = xprt_prepare_transmit(task);
1815 if (task->tk_status == -EAGAIN) {
1816 /*
1817 * Could not reserve the transport. Try again after the
1818 * transport is released.
1819 */
1820 task->tk_status = 0;
1821 task->tk_action = call_bc_transmit;
1822 return;
1823 }
1824
1825 task->tk_action = rpc_exit_task;
1826 if (task->tk_status < 0) {
1827 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1828 "error: %d\n", task->tk_status);
1829 return;
1830 }
1831
1832 xprt_transmit(task);
1833 xprt_end_transmit(task);
1834 dprint_status(task);
1835 switch (task->tk_status) {
1836 case 0:
1837 /* Success */
1838 break;
1839 case -EHOSTDOWN:
1840 case -EHOSTUNREACH:
1841 case -ENETUNREACH:
1842 case -ETIMEDOUT:
1843 /*
1844 * Problem reaching the server. Disconnect and let the
1845 * forechannel reestablish the connection. The server will
1846 * have to retransmit the backchannel request and we'll
1847 * reprocess it. Since these ops are idempotent, there's no
1848 * need to cache our reply at this time.
1849 */
1850 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1851 "error: %d\n", task->tk_status);
1852 xprt_conditional_disconnect(req->rq_xprt,
1853 req->rq_connect_cookie);
1854 break;
1855 default:
1856 /*
1857 * We were unable to reply and will have to drop the
1858 * request. The server should reconnect and retransmit.
1859 */
1860 WARN_ON_ONCE(task->tk_status == -EAGAIN);
1861 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1862 "error: %d\n", task->tk_status);
1863 break;
1864 }
1865 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1866 }
1867 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1868
1869 /*
1870 * 6. Sort out the RPC call status
1871 */
1872 static void
1873 call_status(struct rpc_task *task)
1874 {
1875 struct rpc_clnt *clnt = task->tk_client;
1876 struct rpc_rqst *req = task->tk_rqstp;
1877 int status;
1878
1879 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1880 task->tk_status = req->rq_reply_bytes_recvd;
1881
1882 dprint_status(task);
1883
1884 status = task->tk_status;
1885 if (status >= 0) {
1886 task->tk_action = call_decode;
1887 return;
1888 }
1889
1890 trace_rpc_call_status(task);
1891 task->tk_status = 0;
1892 switch(status) {
1893 case -EHOSTDOWN:
1894 case -EHOSTUNREACH:
1895 case -ENETUNREACH:
1896 /*
1897 * Delay any retries for 3 seconds, then handle as if it
1898 * were a timeout.
1899 */
1900 rpc_delay(task, 3*HZ);
1901 case -ETIMEDOUT:
1902 task->tk_action = call_timeout;
1903 if (task->tk_client->cl_discrtry)
1904 xprt_conditional_disconnect(req->rq_xprt,
1905 req->rq_connect_cookie);
1906 break;
1907 case -ECONNRESET:
1908 case -ECONNREFUSED:
1909 rpc_force_rebind(clnt);
1910 rpc_delay(task, 3*HZ);
1911 case -EPIPE:
1912 case -ENOTCONN:
1913 task->tk_action = call_bind;
1914 break;
1915 case -EAGAIN:
1916 task->tk_action = call_transmit;
1917 break;
1918 case -EIO:
1919 /* shutdown or soft timeout */
1920 rpc_exit(task, status);
1921 break;
1922 default:
1923 if (clnt->cl_chatty)
1924 printk("%s: RPC call returned error %d\n",
1925 clnt->cl_program->name, -status);
1926 rpc_exit(task, status);
1927 }
1928 }
1929
1930 /*
1931 * 6a. Handle RPC timeout
1932 * We do not release the request slot, so we keep using the
1933 * same XID for all retransmits.
1934 */
1935 static void
1936 call_timeout(struct rpc_task *task)
1937 {
1938 struct rpc_clnt *clnt = task->tk_client;
1939
1940 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1941 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1942 goto retry;
1943 }
1944
1945 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1946 task->tk_timeouts++;
1947
1948 if (RPC_IS_SOFTCONN(task)) {
1949 rpc_exit(task, -ETIMEDOUT);
1950 return;
1951 }
1952 if (RPC_IS_SOFT(task)) {
1953 if (clnt->cl_chatty) {
1954 rcu_read_lock();
1955 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1956 clnt->cl_program->name,
1957 rcu_dereference(clnt->cl_xprt)->servername);
1958 rcu_read_unlock();
1959 }
1960 if (task->tk_flags & RPC_TASK_TIMEOUT)
1961 rpc_exit(task, -ETIMEDOUT);
1962 else
1963 rpc_exit(task, -EIO);
1964 return;
1965 }
1966
1967 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1968 task->tk_flags |= RPC_CALL_MAJORSEEN;
1969 if (clnt->cl_chatty) {
1970 rcu_read_lock();
1971 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1972 clnt->cl_program->name,
1973 rcu_dereference(clnt->cl_xprt)->servername);
1974 rcu_read_unlock();
1975 }
1976 }
1977 rpc_force_rebind(clnt);
1978 /*
1979 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1980 * event? RFC2203 requires the server to drop all such requests.
1981 */
1982 rpcauth_invalcred(task);
1983
1984 retry:
1985 clnt->cl_stats->rpcretrans++;
1986 task->tk_action = call_bind;
1987 task->tk_status = 0;
1988 }
1989
1990 /*
1991 * 7. Decode the RPC reply
1992 */
1993 static void
1994 call_decode(struct rpc_task *task)
1995 {
1996 struct rpc_clnt *clnt = task->tk_client;
1997 struct rpc_rqst *req = task->tk_rqstp;
1998 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
1999 __be32 *p;
2000
2001 dprint_status(task);
2002
2003 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2004 if (clnt->cl_chatty) {
2005 rcu_read_lock();
2006 printk(KERN_NOTICE "%s: server %s OK\n",
2007 clnt->cl_program->name,
2008 rcu_dereference(clnt->cl_xprt)->servername);
2009 rcu_read_unlock();
2010 }
2011 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2012 }
2013
2014 /*
2015 * Ensure that we see all writes made by xprt_complete_rqst()
2016 * before it changed req->rq_reply_bytes_recvd.
2017 */
2018 smp_rmb();
2019 req->rq_rcv_buf.len = req->rq_private_buf.len;
2020
2021 /* Check that the softirq receive buffer is valid */
2022 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2023 sizeof(req->rq_rcv_buf)) != 0);
2024
2025 if (req->rq_rcv_buf.len < 12) {
2026 if (!RPC_IS_SOFT(task)) {
2027 task->tk_action = call_bind;
2028 clnt->cl_stats->rpcretrans++;
2029 goto out_retry;
2030 }
2031 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2032 clnt->cl_program->name, task->tk_status);
2033 task->tk_action = call_timeout;
2034 goto out_retry;
2035 }
2036
2037 p = rpc_verify_header(task);
2038 if (IS_ERR(p)) {
2039 if (p == ERR_PTR(-EAGAIN))
2040 goto out_retry;
2041 return;
2042 }
2043
2044 task->tk_action = rpc_exit_task;
2045
2046 if (decode) {
2047 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2048 task->tk_msg.rpc_resp);
2049 }
2050 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2051 task->tk_status);
2052 return;
2053 out_retry:
2054 task->tk_status = 0;
2055 /* Note: rpc_verify_header() may have freed the RPC slot */
2056 if (task->tk_rqstp == req) {
2057 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2058 if (task->tk_client->cl_discrtry)
2059 xprt_conditional_disconnect(req->rq_xprt,
2060 req->rq_connect_cookie);
2061 }
2062 }
2063
2064 static __be32 *
2065 rpc_encode_header(struct rpc_task *task)
2066 {
2067 struct rpc_clnt *clnt = task->tk_client;
2068 struct rpc_rqst *req = task->tk_rqstp;
2069 __be32 *p = req->rq_svec[0].iov_base;
2070
2071 /* FIXME: check buffer size? */
2072
2073 p = xprt_skip_transport_header(req->rq_xprt, p);
2074 *p++ = req->rq_xid; /* XID */
2075 *p++ = htonl(RPC_CALL); /* CALL */
2076 *p++ = htonl(RPC_VERSION); /* RPC version */
2077 *p++ = htonl(clnt->cl_prog); /* program number */
2078 *p++ = htonl(clnt->cl_vers); /* program version */
2079 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2080 p = rpcauth_marshcred(task, p);
2081 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2082 return p;
2083 }
2084
2085 static __be32 *
2086 rpc_verify_header(struct rpc_task *task)
2087 {
2088 struct rpc_clnt *clnt = task->tk_client;
2089 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2090 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2091 __be32 *p = iov->iov_base;
2092 u32 n;
2093 int error = -EACCES;
2094
2095 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2096 /* RFC-1014 says that the representation of XDR data must be a
2097 * multiple of four bytes
2098 * - if it isn't pointer subtraction in the NFS client may give
2099 * undefined results
2100 */
2101 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2102 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2103 task->tk_rqstp->rq_rcv_buf.len);
2104 error = -EIO;
2105 goto out_err;
2106 }
2107 if ((len -= 3) < 0)
2108 goto out_overflow;
2109
2110 p += 1; /* skip XID */
2111 if ((n = ntohl(*p++)) != RPC_REPLY) {
2112 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2113 task->tk_pid, __func__, n);
2114 error = -EIO;
2115 goto out_garbage;
2116 }
2117
2118 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2119 if (--len < 0)
2120 goto out_overflow;
2121 switch ((n = ntohl(*p++))) {
2122 case RPC_AUTH_ERROR:
2123 break;
2124 case RPC_MISMATCH:
2125 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2126 task->tk_pid, __func__);
2127 error = -EPROTONOSUPPORT;
2128 goto out_err;
2129 default:
2130 dprintk("RPC: %5u %s: RPC call rejected, "
2131 "unknown error: %x\n",
2132 task->tk_pid, __func__, n);
2133 error = -EIO;
2134 goto out_err;
2135 }
2136 if (--len < 0)
2137 goto out_overflow;
2138 switch ((n = ntohl(*p++))) {
2139 case RPC_AUTH_REJECTEDCRED:
2140 case RPC_AUTH_REJECTEDVERF:
2141 case RPCSEC_GSS_CREDPROBLEM:
2142 case RPCSEC_GSS_CTXPROBLEM:
2143 if (!task->tk_cred_retry)
2144 break;
2145 task->tk_cred_retry--;
2146 dprintk("RPC: %5u %s: retry stale creds\n",
2147 task->tk_pid, __func__);
2148 rpcauth_invalcred(task);
2149 /* Ensure we obtain a new XID! */
2150 xprt_release(task);
2151 task->tk_action = call_reserve;
2152 goto out_retry;
2153 case RPC_AUTH_BADCRED:
2154 case RPC_AUTH_BADVERF:
2155 /* possibly garbled cred/verf? */
2156 if (!task->tk_garb_retry)
2157 break;
2158 task->tk_garb_retry--;
2159 dprintk("RPC: %5u %s: retry garbled creds\n",
2160 task->tk_pid, __func__);
2161 task->tk_action = call_bind;
2162 goto out_retry;
2163 case RPC_AUTH_TOOWEAK:
2164 rcu_read_lock();
2165 printk(KERN_NOTICE "RPC: server %s requires stronger "
2166 "authentication.\n",
2167 rcu_dereference(clnt->cl_xprt)->servername);
2168 rcu_read_unlock();
2169 break;
2170 default:
2171 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2172 task->tk_pid, __func__, n);
2173 error = -EIO;
2174 }
2175 dprintk("RPC: %5u %s: call rejected %d\n",
2176 task->tk_pid, __func__, n);
2177 goto out_err;
2178 }
2179 p = rpcauth_checkverf(task, p);
2180 if (IS_ERR(p)) {
2181 error = PTR_ERR(p);
2182 dprintk("RPC: %5u %s: auth check failed with %d\n",
2183 task->tk_pid, __func__, error);
2184 goto out_garbage; /* bad verifier, retry */
2185 }
2186 len = p - (__be32 *)iov->iov_base - 1;
2187 if (len < 0)
2188 goto out_overflow;
2189 switch ((n = ntohl(*p++))) {
2190 case RPC_SUCCESS:
2191 return p;
2192 case RPC_PROG_UNAVAIL:
2193 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2194 "by server %s\n", task->tk_pid, __func__,
2195 (unsigned int)clnt->cl_prog,
2196 rcu_dereference(clnt->cl_xprt)->servername);
2197 error = -EPFNOSUPPORT;
2198 goto out_err;
2199 case RPC_PROG_MISMATCH:
2200 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2201 "by server %s\n", task->tk_pid, __func__,
2202 (unsigned int)clnt->cl_prog,
2203 (unsigned int)clnt->cl_vers,
2204 rcu_dereference(clnt->cl_xprt)->servername);
2205 error = -EPROTONOSUPPORT;
2206 goto out_err;
2207 case RPC_PROC_UNAVAIL:
2208 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2209 "version %u on server %s\n",
2210 task->tk_pid, __func__,
2211 rpc_proc_name(task),
2212 clnt->cl_prog, clnt->cl_vers,
2213 rcu_dereference(clnt->cl_xprt)->servername);
2214 error = -EOPNOTSUPP;
2215 goto out_err;
2216 case RPC_GARBAGE_ARGS:
2217 dprintk("RPC: %5u %s: server saw garbage\n",
2218 task->tk_pid, __func__);
2219 break; /* retry */
2220 default:
2221 dprintk("RPC: %5u %s: server accept status: %x\n",
2222 task->tk_pid, __func__, n);
2223 /* Also retry */
2224 }
2225
2226 out_garbage:
2227 clnt->cl_stats->rpcgarbage++;
2228 if (task->tk_garb_retry) {
2229 task->tk_garb_retry--;
2230 dprintk("RPC: %5u %s: retrying\n",
2231 task->tk_pid, __func__);
2232 task->tk_action = call_bind;
2233 out_retry:
2234 return ERR_PTR(-EAGAIN);
2235 }
2236 out_err:
2237 rpc_exit(task, error);
2238 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2239 __func__, error);
2240 return ERR_PTR(error);
2241 out_overflow:
2242 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2243 __func__);
2244 goto out_garbage;
2245 }
2246
2247 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2248 {
2249 }
2250
2251 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2252 {
2253 return 0;
2254 }
2255
2256 static struct rpc_procinfo rpcproc_null = {
2257 .p_encode = rpcproc_encode_null,
2258 .p_decode = rpcproc_decode_null,
2259 };
2260
2261 static int rpc_ping(struct rpc_clnt *clnt)
2262 {
2263 struct rpc_message msg = {
2264 .rpc_proc = &rpcproc_null,
2265 };
2266 int err;
2267 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2268 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2269 put_rpccred(msg.rpc_cred);
2270 return err;
2271 }
2272
2273 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2274 {
2275 struct rpc_message msg = {
2276 .rpc_proc = &rpcproc_null,
2277 .rpc_cred = cred,
2278 };
2279 struct rpc_task_setup task_setup_data = {
2280 .rpc_client = clnt,
2281 .rpc_message = &msg,
2282 .callback_ops = &rpc_default_ops,
2283 .flags = flags,
2284 };
2285 return rpc_run_task(&task_setup_data);
2286 }
2287 EXPORT_SYMBOL_GPL(rpc_call_null);
2288
2289 #ifdef RPC_DEBUG
2290 static void rpc_show_header(void)
2291 {
2292 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2293 "-timeout ---ops--\n");
2294 }
2295
2296 static void rpc_show_task(const struct rpc_clnt *clnt,
2297 const struct rpc_task *task)
2298 {
2299 const char *rpc_waitq = "none";
2300
2301 if (RPC_IS_QUEUED(task))
2302 rpc_waitq = rpc_qname(task->tk_waitqueue);
2303
2304 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2305 task->tk_pid, task->tk_flags, task->tk_status,
2306 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2307 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2308 task->tk_action, rpc_waitq);
2309 }
2310
2311 void rpc_show_tasks(struct net *net)
2312 {
2313 struct rpc_clnt *clnt;
2314 struct rpc_task *task;
2315 int header = 0;
2316 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2317
2318 spin_lock(&sn->rpc_client_lock);
2319 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2320 spin_lock(&clnt->cl_lock);
2321 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2322 if (!header) {
2323 rpc_show_header();
2324 header++;
2325 }
2326 rpc_show_task(clnt, task);
2327 }
2328 spin_unlock(&clnt->cl_lock);
2329 }
2330 spin_unlock(&sn->rpc_client_lock);
2331 }
2332 #endif
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