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KEYS: add missing permission check for request_key() destination
[linux/fpc-iii.git] / net / sunrpc / clnt.c
blob710d4191e9d5e589238d1f337fe8ab6e3bc47b02
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/rcupdate.h>
29 #include <linux/utsname.h>
30 #include <linux/workqueue.h>
31 #include <linux/in.h>
32 #include <linux/in6.h>
33 #include <linux/un.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 struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
268 struct rpc_xprt *xprt,
269 const struct rpc_timeout *timeout)
270 {
271 struct rpc_xprt *old;
272
273 spin_lock(&clnt->cl_lock);
274 old = rcu_dereference_protected(clnt->cl_xprt,
275 lockdep_is_held(&clnt->cl_lock));
276
277 if (!xprt_bound(xprt))
278 clnt->cl_autobind = 1;
279
280 clnt->cl_timeout = timeout;
281 rcu_assign_pointer(clnt->cl_xprt, xprt);
282 spin_unlock(&clnt->cl_lock);
283
284 return old;
285 }
286
287 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
288 {
289 clnt->cl_nodelen = strlen(nodename);
290 if (clnt->cl_nodelen > UNX_MAXNODENAME)
291 clnt->cl_nodelen = UNX_MAXNODENAME;
292 memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen);
293 }
294
295 static int rpc_client_register(struct rpc_clnt *clnt,
296 rpc_authflavor_t pseudoflavor,
297 const char *client_name)
298 {
299 struct rpc_auth_create_args auth_args = {
300 .pseudoflavor = pseudoflavor,
301 .target_name = client_name,
302 };
303 struct rpc_auth *auth;
304 struct net *net = rpc_net_ns(clnt);
305 struct super_block *pipefs_sb;
306 int err;
307
308 pipefs_sb = rpc_get_sb_net(net);
309 if (pipefs_sb) {
310 err = rpc_setup_pipedir(pipefs_sb, clnt);
311 if (err)
312 goto out;
313 }
314
315 rpc_register_client(clnt);
316 if (pipefs_sb)
317 rpc_put_sb_net(net);
318
319 auth = rpcauth_create(&auth_args, clnt);
320 if (IS_ERR(auth)) {
321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
322 pseudoflavor);
323 err = PTR_ERR(auth);
324 goto err_auth;
325 }
326 return 0;
327 err_auth:
328 pipefs_sb = rpc_get_sb_net(net);
329 rpc_unregister_client(clnt);
330 __rpc_clnt_remove_pipedir(clnt);
331 out:
332 if (pipefs_sb)
333 rpc_put_sb_net(net);
334 return err;
335 }
336
337 static DEFINE_IDA(rpc_clids);
338
339 void rpc_cleanup_clids(void)
340 {
341 ida_destroy(&rpc_clids);
342 }
343
344 static int rpc_alloc_clid(struct rpc_clnt *clnt)
345 {
346 int clid;
347
348 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
349 if (clid < 0)
350 return clid;
351 clnt->cl_clid = clid;
352 return 0;
353 }
354
355 static void rpc_free_clid(struct rpc_clnt *clnt)
356 {
357 ida_simple_remove(&rpc_clids, clnt->cl_clid);
358 }
359
360 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
361 struct rpc_xprt *xprt,
362 struct rpc_clnt *parent)
363 {
364 const struct rpc_program *program = args->program;
365 const struct rpc_version *version;
366 struct rpc_clnt *clnt = NULL;
367 const struct rpc_timeout *timeout;
368 int err;
369
370 /* sanity check the name before trying to print it */
371 dprintk("RPC: creating %s client for %s (xprt %p)\n",
372 program->name, args->servername, xprt);
373
374 err = rpciod_up();
375 if (err)
376 goto out_no_rpciod;
377
378 err = -EINVAL;
379 if (args->version >= program->nrvers)
380 goto out_err;
381 version = program->version[args->version];
382 if (version == NULL)
383 goto out_err;
384
385 err = -ENOMEM;
386 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
387 if (!clnt)
388 goto out_err;
389 clnt->cl_parent = parent ? : clnt;
390
391 err = rpc_alloc_clid(clnt);
392 if (err)
393 goto out_no_clid;
394
395 clnt->cl_procinfo = version->procs;
396 clnt->cl_maxproc = version->nrprocs;
397 clnt->cl_prog = args->prognumber ? : program->number;
398 clnt->cl_vers = version->number;
399 clnt->cl_stats = program->stats;
400 clnt->cl_metrics = rpc_alloc_iostats(clnt);
401 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
402 err = -ENOMEM;
403 if (clnt->cl_metrics == NULL)
404 goto out_no_stats;
405 clnt->cl_program = program;
406 INIT_LIST_HEAD(&clnt->cl_tasks);
407 spin_lock_init(&clnt->cl_lock);
408
409 timeout = xprt->timeout;
410 if (args->timeout != NULL) {
411 memcpy(&clnt->cl_timeout_default, args->timeout,
412 sizeof(clnt->cl_timeout_default));
413 timeout = &clnt->cl_timeout_default;
414 }
415
416 rpc_clnt_set_transport(clnt, xprt, timeout);
417
418 clnt->cl_rtt = &clnt->cl_rtt_default;
419 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
420
421 atomic_set(&clnt->cl_count, 1);
422
423 /* save the nodename */
424 rpc_clnt_set_nodename(clnt, utsname()->nodename);
425
426 err = rpc_client_register(clnt, args->authflavor, args->client_name);
427 if (err)
428 goto out_no_path;
429 if (parent)
430 atomic_inc(&parent->cl_count);
431 return clnt;
432
433 out_no_path:
434 rpc_free_iostats(clnt->cl_metrics);
435 out_no_stats:
436 rpc_free_clid(clnt);
437 out_no_clid:
438 kfree(clnt);
439 out_err:
440 rpciod_down();
441 out_no_rpciod:
442 xprt_put(xprt);
443 return ERR_PTR(err);
444 }
445
446 struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
447 struct rpc_xprt *xprt)
448 {
449 struct rpc_clnt *clnt = NULL;
450
451 clnt = rpc_new_client(args, xprt, NULL);
452 if (IS_ERR(clnt))
453 return clnt;
454
455 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
456 int err = rpc_ping(clnt);
457 if (err != 0) {
458 rpc_shutdown_client(clnt);
459 return ERR_PTR(err);
460 }
461 }
462
463 clnt->cl_softrtry = 1;
464 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
465 clnt->cl_softrtry = 0;
466
467 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
468 clnt->cl_autobind = 1;
469 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
470 clnt->cl_noretranstimeo = 1;
471 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
472 clnt->cl_discrtry = 1;
473 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
474 clnt->cl_chatty = 1;
475
476 return clnt;
477 }
478 EXPORT_SYMBOL_GPL(rpc_create_xprt);
479
480 /**
481 * rpc_create - create an RPC client and transport with one call
482 * @args: rpc_clnt create argument structure
483 *
484 * Creates and initializes an RPC transport and an RPC client.
485 *
486 * It can ping the server in order to determine if it is up, and to see if
487 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
488 * this behavior so asynchronous tasks can also use rpc_create.
489 */
490 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
491 {
492 struct rpc_xprt *xprt;
493 struct xprt_create xprtargs = {
494 .net = args->net,
495 .ident = args->protocol,
496 .srcaddr = args->saddress,
497 .dstaddr = args->address,
498 .addrlen = args->addrsize,
499 .servername = args->servername,
500 .bc_xprt = args->bc_xprt,
501 };
502 char servername[48];
503
504 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
505 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
506 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
507 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
508 /*
509 * If the caller chooses not to specify a hostname, whip
510 * up a string representation of the passed-in address.
511 */
512 if (xprtargs.servername == NULL) {
513 struct sockaddr_un *sun =
514 (struct sockaddr_un *)args->address;
515 struct sockaddr_in *sin =
516 (struct sockaddr_in *)args->address;
517 struct sockaddr_in6 *sin6 =
518 (struct sockaddr_in6 *)args->address;
519
520 servername[0] = '\0';
521 switch (args->address->sa_family) {
522 case AF_LOCAL:
523 snprintf(servername, sizeof(servername), "%s",
524 sun->sun_path);
525 break;
526 case AF_INET:
527 snprintf(servername, sizeof(servername), "%pI4",
528 &sin->sin_addr.s_addr);
529 break;
530 case AF_INET6:
531 snprintf(servername, sizeof(servername), "%pI6",
532 &sin6->sin6_addr);
533 break;
534 default:
535 /* caller wants default server name, but
536 * address family isn't recognized. */
537 return ERR_PTR(-EINVAL);
538 }
539 xprtargs.servername = servername;
540 }
541
542 xprt = xprt_create_transport(&xprtargs);
543 if (IS_ERR(xprt))
544 return (struct rpc_clnt *)xprt;
545
546 /*
547 * By default, kernel RPC client connects from a reserved port.
548 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
549 * but it is always enabled for rpciod, which handles the connect
550 * operation.
551 */
552 xprt->resvport = 1;
553 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
554 xprt->resvport = 0;
555
556 return rpc_create_xprt(args, xprt);
557 }
558 EXPORT_SYMBOL_GPL(rpc_create);
559
560 /*
561 * This function clones the RPC client structure. It allows us to share the
562 * same transport while varying parameters such as the authentication
563 * flavour.
564 */
565 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
566 struct rpc_clnt *clnt)
567 {
568 struct rpc_xprt *xprt;
569 struct rpc_clnt *new;
570 int err;
571
572 err = -ENOMEM;
573 rcu_read_lock();
574 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
575 rcu_read_unlock();
576 if (xprt == NULL)
577 goto out_err;
578 args->servername = xprt->servername;
579
580 new = rpc_new_client(args, xprt, clnt);
581 if (IS_ERR(new)) {
582 err = PTR_ERR(new);
583 goto out_err;
584 }
585
586 /* Turn off autobind on clones */
587 new->cl_autobind = 0;
588 new->cl_softrtry = clnt->cl_softrtry;
589 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
590 new->cl_discrtry = clnt->cl_discrtry;
591 new->cl_chatty = clnt->cl_chatty;
592 return new;
593
594 out_err:
595 dprintk("RPC: %s: returned error %d\n", __func__, err);
596 return ERR_PTR(err);
597 }
598
599 /**
600 * rpc_clone_client - Clone an RPC client structure
601 *
602 * @clnt: RPC client whose parameters are copied
603 *
604 * Returns a fresh RPC client or an ERR_PTR.
605 */
606 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
607 {
608 struct rpc_create_args args = {
609 .program = clnt->cl_program,
610 .prognumber = clnt->cl_prog,
611 .version = clnt->cl_vers,
612 .authflavor = clnt->cl_auth->au_flavor,
613 };
614 return __rpc_clone_client(&args, clnt);
615 }
616 EXPORT_SYMBOL_GPL(rpc_clone_client);
617
618 /**
619 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
620 *
621 * @clnt: RPC client whose parameters are copied
622 * @flavor: security flavor for new client
623 *
624 * Returns a fresh RPC client or an ERR_PTR.
625 */
626 struct rpc_clnt *
627 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
628 {
629 struct rpc_create_args args = {
630 .program = clnt->cl_program,
631 .prognumber = clnt->cl_prog,
632 .version = clnt->cl_vers,
633 .authflavor = flavor,
634 };
635 return __rpc_clone_client(&args, clnt);
636 }
637 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
638
639 /**
640 * rpc_switch_client_transport: switch the RPC transport on the fly
641 * @clnt: pointer to a struct rpc_clnt
642 * @args: pointer to the new transport arguments
643 * @timeout: pointer to the new timeout parameters
644 *
645 * This function allows the caller to switch the RPC transport for the
646 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
647 * server, for instance. It assumes that the caller has ensured that
648 * there are no active RPC tasks by using some form of locking.
649 *
650 * Returns zero if "clnt" is now using the new xprt. Otherwise a
651 * negative errno is returned, and "clnt" continues to use the old
652 * xprt.
653 */
654 int rpc_switch_client_transport(struct rpc_clnt *clnt,
655 struct xprt_create *args,
656 const struct rpc_timeout *timeout)
657 {
658 const struct rpc_timeout *old_timeo;
659 rpc_authflavor_t pseudoflavor;
660 struct rpc_xprt *xprt, *old;
661 struct rpc_clnt *parent;
662 int err;
663
664 xprt = xprt_create_transport(args);
665 if (IS_ERR(xprt)) {
666 dprintk("RPC: failed to create new xprt for clnt %p\n",
667 clnt);
668 return PTR_ERR(xprt);
669 }
670
671 pseudoflavor = clnt->cl_auth->au_flavor;
672
673 old_timeo = clnt->cl_timeout;
674 old = rpc_clnt_set_transport(clnt, xprt, timeout);
675
676 rpc_unregister_client(clnt);
677 __rpc_clnt_remove_pipedir(clnt);
678
679 /*
680 * A new transport was created. "clnt" therefore
681 * becomes the root of a new cl_parent tree. clnt's
682 * children, if it has any, still point to the old xprt.
683 */
684 parent = clnt->cl_parent;
685 clnt->cl_parent = clnt;
686
687 /*
688 * The old rpc_auth cache cannot be re-used. GSS
689 * contexts in particular are between a single
690 * client and server.
691 */
692 err = rpc_client_register(clnt, pseudoflavor, NULL);
693 if (err)
694 goto out_revert;
695
696 synchronize_rcu();
697 if (parent != clnt)
698 rpc_release_client(parent);
699 xprt_put(old);
700 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
701 return 0;
702
703 out_revert:
704 rpc_clnt_set_transport(clnt, old, old_timeo);
705 clnt->cl_parent = parent;
706 rpc_client_register(clnt, pseudoflavor, NULL);
707 xprt_put(xprt);
708 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
709 return err;
710 }
711 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
712
713 /*
714 * Kill all tasks for the given client.
715 * XXX: kill their descendants as well?
716 */
717 void rpc_killall_tasks(struct rpc_clnt *clnt)
718 {
719 struct rpc_task *rovr;
720
721
722 if (list_empty(&clnt->cl_tasks))
723 return;
724 dprintk("RPC: killing all tasks for client %p\n", clnt);
725 /*
726 * Spin lock all_tasks to prevent changes...
727 */
728 spin_lock(&clnt->cl_lock);
729 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
730 if (!RPC_IS_ACTIVATED(rovr))
731 continue;
732 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
733 rovr->tk_flags |= RPC_TASK_KILLED;
734 rpc_exit(rovr, -EIO);
735 if (RPC_IS_QUEUED(rovr))
736 rpc_wake_up_queued_task(rovr->tk_waitqueue,
737 rovr);
738 }
739 }
740 spin_unlock(&clnt->cl_lock);
741 }
742 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
743
744 /*
745 * Properly shut down an RPC client, terminating all outstanding
746 * requests.
747 */
748 void rpc_shutdown_client(struct rpc_clnt *clnt)
749 {
750 might_sleep();
751
752 dprintk_rcu("RPC: shutting down %s client for %s\n",
753 clnt->cl_program->name,
754 rcu_dereference(clnt->cl_xprt)->servername);
755
756 while (!list_empty(&clnt->cl_tasks)) {
757 rpc_killall_tasks(clnt);
758 wait_event_timeout(destroy_wait,
759 list_empty(&clnt->cl_tasks), 1*HZ);
760 }
761
762 rpc_release_client(clnt);
763 }
764 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
765
766 /*
767 * Free an RPC client
768 */
769 static struct rpc_clnt *
770 rpc_free_client(struct rpc_clnt *clnt)
771 {
772 struct rpc_clnt *parent = NULL;
773
774 dprintk_rcu("RPC: destroying %s client for %s\n",
775 clnt->cl_program->name,
776 rcu_dereference(clnt->cl_xprt)->servername);
777 if (clnt->cl_parent != clnt)
778 parent = clnt->cl_parent;
779 rpc_clnt_remove_pipedir(clnt);
780 rpc_unregister_client(clnt);
781 rpc_free_iostats(clnt->cl_metrics);
782 clnt->cl_metrics = NULL;
783 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
784 rpciod_down();
785 rpc_free_clid(clnt);
786 kfree(clnt);
787 return parent;
788 }
789
790 /*
791 * Free an RPC client
792 */
793 static struct rpc_clnt *
794 rpc_free_auth(struct rpc_clnt *clnt)
795 {
796 if (clnt->cl_auth == NULL)
797 return rpc_free_client(clnt);
798
799 /*
800 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
801 * release remaining GSS contexts. This mechanism ensures
802 * that it can do so safely.
803 */
804 atomic_inc(&clnt->cl_count);
805 rpcauth_release(clnt->cl_auth);
806 clnt->cl_auth = NULL;
807 if (atomic_dec_and_test(&clnt->cl_count))
808 return rpc_free_client(clnt);
809 return NULL;
810 }
811
812 /*
813 * Release reference to the RPC client
814 */
815 void
816 rpc_release_client(struct rpc_clnt *clnt)
817 {
818 dprintk("RPC: rpc_release_client(%p)\n", clnt);
819
820 do {
821 if (list_empty(&clnt->cl_tasks))
822 wake_up(&destroy_wait);
823 if (!atomic_dec_and_test(&clnt->cl_count))
824 break;
825 clnt = rpc_free_auth(clnt);
826 } while (clnt != NULL);
827 }
828 EXPORT_SYMBOL_GPL(rpc_release_client);
829
830 /**
831 * rpc_bind_new_program - bind a new RPC program to an existing client
832 * @old: old rpc_client
833 * @program: rpc program to set
834 * @vers: rpc program version
835 *
836 * Clones the rpc client and sets up a new RPC program. This is mainly
837 * of use for enabling different RPC programs to share the same transport.
838 * The Sun NFSv2/v3 ACL protocol can do this.
839 */
840 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
841 const struct rpc_program *program,
842 u32 vers)
843 {
844 struct rpc_create_args args = {
845 .program = program,
846 .prognumber = program->number,
847 .version = vers,
848 .authflavor = old->cl_auth->au_flavor,
849 };
850 struct rpc_clnt *clnt;
851 int err;
852
853 clnt = __rpc_clone_client(&args, old);
854 if (IS_ERR(clnt))
855 goto out;
856 err = rpc_ping(clnt);
857 if (err != 0) {
858 rpc_shutdown_client(clnt);
859 clnt = ERR_PTR(err);
860 }
861 out:
862 return clnt;
863 }
864 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
865
866 void rpc_task_release_client(struct rpc_task *task)
867 {
868 struct rpc_clnt *clnt = task->tk_client;
869
870 if (clnt != NULL) {
871 /* Remove from client task list */
872 spin_lock(&clnt->cl_lock);
873 list_del(&task->tk_task);
874 spin_unlock(&clnt->cl_lock);
875 task->tk_client = NULL;
876
877 rpc_release_client(clnt);
878 }
879 }
880
881 static
882 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
883 {
884 if (clnt != NULL) {
885 rpc_task_release_client(task);
886 task->tk_client = clnt;
887 atomic_inc(&clnt->cl_count);
888 if (clnt->cl_softrtry)
889 task->tk_flags |= RPC_TASK_SOFT;
890 if (clnt->cl_noretranstimeo)
891 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
892 if (sk_memalloc_socks()) {
893 struct rpc_xprt *xprt;
894
895 rcu_read_lock();
896 xprt = rcu_dereference(clnt->cl_xprt);
897 if (xprt->swapper)
898 task->tk_flags |= RPC_TASK_SWAPPER;
899 rcu_read_unlock();
900 }
901 /* Add to the client's list of all tasks */
902 spin_lock(&clnt->cl_lock);
903 list_add_tail(&task->tk_task, &clnt->cl_tasks);
904 spin_unlock(&clnt->cl_lock);
905 }
906 }
907
908 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
909 {
910 rpc_task_release_client(task);
911 rpc_task_set_client(task, clnt);
912 }
913 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
914
915
916 static void
917 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
918 {
919 if (msg != NULL) {
920 task->tk_msg.rpc_proc = msg->rpc_proc;
921 task->tk_msg.rpc_argp = msg->rpc_argp;
922 task->tk_msg.rpc_resp = msg->rpc_resp;
923 if (msg->rpc_cred != NULL)
924 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
925 }
926 }
927
928 /*
929 * Default callback for async RPC calls
930 */
931 static void
932 rpc_default_callback(struct rpc_task *task, void *data)
933 {
934 }
935
936 static const struct rpc_call_ops rpc_default_ops = {
937 .rpc_call_done = rpc_default_callback,
938 };
939
940 /**
941 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
942 * @task_setup_data: pointer to task initialisation data
943 */
944 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
945 {
946 struct rpc_task *task;
947
948 task = rpc_new_task(task_setup_data);
949 if (IS_ERR(task))
950 goto out;
951
952 rpc_task_set_client(task, task_setup_data->rpc_client);
953 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
954
955 if (task->tk_action == NULL)
956 rpc_call_start(task);
957
958 atomic_inc(&task->tk_count);
959 rpc_execute(task);
960 out:
961 return task;
962 }
963 EXPORT_SYMBOL_GPL(rpc_run_task);
964
965 /**
966 * rpc_call_sync - Perform a synchronous RPC call
967 * @clnt: pointer to RPC client
968 * @msg: RPC call parameters
969 * @flags: RPC call flags
970 */
971 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
972 {
973 struct rpc_task *task;
974 struct rpc_task_setup task_setup_data = {
975 .rpc_client = clnt,
976 .rpc_message = msg,
977 .callback_ops = &rpc_default_ops,
978 .flags = flags,
979 };
980 int status;
981
982 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
983 if (flags & RPC_TASK_ASYNC) {
984 rpc_release_calldata(task_setup_data.callback_ops,
985 task_setup_data.callback_data);
986 return -EINVAL;
987 }
988
989 task = rpc_run_task(&task_setup_data);
990 if (IS_ERR(task))
991 return PTR_ERR(task);
992 status = task->tk_status;
993 rpc_put_task(task);
994 return status;
995 }
996 EXPORT_SYMBOL_GPL(rpc_call_sync);
997
998 /**
999 * rpc_call_async - Perform an asynchronous RPC call
1000 * @clnt: pointer to RPC client
1001 * @msg: RPC call parameters
1002 * @flags: RPC call flags
1003 * @tk_ops: RPC call ops
1004 * @data: user call data
1005 */
1006 int
1007 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1008 const struct rpc_call_ops *tk_ops, void *data)
1009 {
1010 struct rpc_task *task;
1011 struct rpc_task_setup task_setup_data = {
1012 .rpc_client = clnt,
1013 .rpc_message = msg,
1014 .callback_ops = tk_ops,
1015 .callback_data = data,
1016 .flags = flags|RPC_TASK_ASYNC,
1017 };
1018
1019 task = rpc_run_task(&task_setup_data);
1020 if (IS_ERR(task))
1021 return PTR_ERR(task);
1022 rpc_put_task(task);
1023 return 0;
1024 }
1025 EXPORT_SYMBOL_GPL(rpc_call_async);
1026
1027 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1028 /**
1029 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1030 * rpc_execute against it
1031 * @req: RPC request
1032 * @tk_ops: RPC call ops
1033 */
1034 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1035 const struct rpc_call_ops *tk_ops)
1036 {
1037 struct rpc_task *task;
1038 struct xdr_buf *xbufp = &req->rq_snd_buf;
1039 struct rpc_task_setup task_setup_data = {
1040 .callback_ops = tk_ops,
1041 };
1042
1043 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1044 /*
1045 * Create an rpc_task to send the data
1046 */
1047 task = rpc_new_task(&task_setup_data);
1048 if (IS_ERR(task)) {
1049 xprt_free_bc_request(req);
1050 goto out;
1051 }
1052 task->tk_rqstp = req;
1053
1054 /*
1055 * Set up the xdr_buf length.
1056 * This also indicates that the buffer is XDR encoded already.
1057 */
1058 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1059 xbufp->tail[0].iov_len;
1060
1061 task->tk_action = call_bc_transmit;
1062 atomic_inc(&task->tk_count);
1063 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1064 rpc_execute(task);
1065
1066 out:
1067 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1068 return task;
1069 }
1070 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1071
1072 void
1073 rpc_call_start(struct rpc_task *task)
1074 {
1075 task->tk_action = call_start;
1076 }
1077 EXPORT_SYMBOL_GPL(rpc_call_start);
1078
1079 /**
1080 * rpc_peeraddr - extract remote peer address from clnt's xprt
1081 * @clnt: RPC client structure
1082 * @buf: target buffer
1083 * @bufsize: length of target buffer
1084 *
1085 * Returns the number of bytes that are actually in the stored address.
1086 */
1087 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1088 {
1089 size_t bytes;
1090 struct rpc_xprt *xprt;
1091
1092 rcu_read_lock();
1093 xprt = rcu_dereference(clnt->cl_xprt);
1094
1095 bytes = xprt->addrlen;
1096 if (bytes > bufsize)
1097 bytes = bufsize;
1098 memcpy(buf, &xprt->addr, bytes);
1099 rcu_read_unlock();
1100
1101 return bytes;
1102 }
1103 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1104
1105 /**
1106 * rpc_peeraddr2str - return remote peer address in printable format
1107 * @clnt: RPC client structure
1108 * @format: address format
1109 *
1110 * NB: the lifetime of the memory referenced by the returned pointer is
1111 * the same as the rpc_xprt itself. As long as the caller uses this
1112 * pointer, it must hold the RCU read lock.
1113 */
1114 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1115 enum rpc_display_format_t format)
1116 {
1117 struct rpc_xprt *xprt;
1118
1119 xprt = rcu_dereference(clnt->cl_xprt);
1120
1121 if (xprt->address_strings[format] != NULL)
1122 return xprt->address_strings[format];
1123 else
1124 return "unprintable";
1125 }
1126 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1127
1128 static const struct sockaddr_in rpc_inaddr_loopback = {
1129 .sin_family = AF_INET,
1130 .sin_addr.s_addr = htonl(INADDR_ANY),
1131 };
1132
1133 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1134 .sin6_family = AF_INET6,
1135 .sin6_addr = IN6ADDR_ANY_INIT,
1136 };
1137
1138 /*
1139 * Try a getsockname() on a connected datagram socket. Using a
1140 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1141 * This conserves the ephemeral port number space.
1142 *
1143 * Returns zero and fills in "buf" if successful; otherwise, a
1144 * negative errno is returned.
1145 */
1146 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1147 struct sockaddr *buf, int buflen)
1148 {
1149 struct socket *sock;
1150 int err;
1151
1152 err = __sock_create(net, sap->sa_family,
1153 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1154 if (err < 0) {
1155 dprintk("RPC: can't create UDP socket (%d)\n", err);
1156 goto out;
1157 }
1158
1159 switch (sap->sa_family) {
1160 case AF_INET:
1161 err = kernel_bind(sock,
1162 (struct sockaddr *)&rpc_inaddr_loopback,
1163 sizeof(rpc_inaddr_loopback));
1164 break;
1165 case AF_INET6:
1166 err = kernel_bind(sock,
1167 (struct sockaddr *)&rpc_in6addr_loopback,
1168 sizeof(rpc_in6addr_loopback));
1169 break;
1170 default:
1171 err = -EAFNOSUPPORT;
1172 goto out;
1173 }
1174 if (err < 0) {
1175 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1176 goto out_release;
1177 }
1178
1179 err = kernel_connect(sock, sap, salen, 0);
1180 if (err < 0) {
1181 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1182 goto out_release;
1183 }
1184
1185 err = kernel_getsockname(sock, buf, &buflen);
1186 if (err < 0) {
1187 dprintk("RPC: getsockname failed (%d)\n", err);
1188 goto out_release;
1189 }
1190
1191 err = 0;
1192 if (buf->sa_family == AF_INET6) {
1193 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1194 sin6->sin6_scope_id = 0;
1195 }
1196 dprintk("RPC: %s succeeded\n", __func__);
1197
1198 out_release:
1199 sock_release(sock);
1200 out:
1201 return err;
1202 }
1203
1204 /*
1205 * Scraping a connected socket failed, so we don't have a useable
1206 * local address. Fallback: generate an address that will prevent
1207 * the server from calling us back.
1208 *
1209 * Returns zero and fills in "buf" if successful; otherwise, a
1210 * negative errno is returned.
1211 */
1212 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1213 {
1214 switch (family) {
1215 case AF_INET:
1216 if (buflen < sizeof(rpc_inaddr_loopback))
1217 return -EINVAL;
1218 memcpy(buf, &rpc_inaddr_loopback,
1219 sizeof(rpc_inaddr_loopback));
1220 break;
1221 case AF_INET6:
1222 if (buflen < sizeof(rpc_in6addr_loopback))
1223 return -EINVAL;
1224 memcpy(buf, &rpc_in6addr_loopback,
1225 sizeof(rpc_in6addr_loopback));
1226 default:
1227 dprintk("RPC: %s: address family not supported\n",
1228 __func__);
1229 return -EAFNOSUPPORT;
1230 }
1231 dprintk("RPC: %s: succeeded\n", __func__);
1232 return 0;
1233 }
1234
1235 /**
1236 * rpc_localaddr - discover local endpoint address for an RPC client
1237 * @clnt: RPC client structure
1238 * @buf: target buffer
1239 * @buflen: size of target buffer, in bytes
1240 *
1241 * Returns zero and fills in "buf" and "buflen" if successful;
1242 * otherwise, a negative errno is returned.
1243 *
1244 * This works even if the underlying transport is not currently connected,
1245 * or if the upper layer never previously provided a source address.
1246 *
1247 * The result of this function call is transient: multiple calls in
1248 * succession may give different results, depending on how local
1249 * networking configuration changes over time.
1250 */
1251 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1252 {
1253 struct sockaddr_storage address;
1254 struct sockaddr *sap = (struct sockaddr *)&address;
1255 struct rpc_xprt *xprt;
1256 struct net *net;
1257 size_t salen;
1258 int err;
1259
1260 rcu_read_lock();
1261 xprt = rcu_dereference(clnt->cl_xprt);
1262 salen = xprt->addrlen;
1263 memcpy(sap, &xprt->addr, salen);
1264 net = get_net(xprt->xprt_net);
1265 rcu_read_unlock();
1266
1267 rpc_set_port(sap, 0);
1268 err = rpc_sockname(net, sap, salen, buf, buflen);
1269 put_net(net);
1270 if (err != 0)
1271 /* Couldn't discover local address, return ANYADDR */
1272 return rpc_anyaddr(sap->sa_family, buf, buflen);
1273 return 0;
1274 }
1275 EXPORT_SYMBOL_GPL(rpc_localaddr);
1276
1277 void
1278 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1279 {
1280 struct rpc_xprt *xprt;
1281
1282 rcu_read_lock();
1283 xprt = rcu_dereference(clnt->cl_xprt);
1284 if (xprt->ops->set_buffer_size)
1285 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1286 rcu_read_unlock();
1287 }
1288 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1289
1290 /**
1291 * rpc_protocol - Get transport protocol number for an RPC client
1292 * @clnt: RPC client to query
1293 *
1294 */
1295 int rpc_protocol(struct rpc_clnt *clnt)
1296 {
1297 int protocol;
1298
1299 rcu_read_lock();
1300 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1301 rcu_read_unlock();
1302 return protocol;
1303 }
1304 EXPORT_SYMBOL_GPL(rpc_protocol);
1305
1306 /**
1307 * rpc_net_ns - Get the network namespace for this RPC client
1308 * @clnt: RPC client to query
1309 *
1310 */
1311 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1312 {
1313 struct net *ret;
1314
1315 rcu_read_lock();
1316 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1317 rcu_read_unlock();
1318 return ret;
1319 }
1320 EXPORT_SYMBOL_GPL(rpc_net_ns);
1321
1322 /**
1323 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1324 * @clnt: RPC client to query
1325 *
1326 * For stream transports, this is one RPC record fragment (see RFC
1327 * 1831), as we don't support multi-record requests yet. For datagram
1328 * transports, this is the size of an IP packet minus the IP, UDP, and
1329 * RPC header sizes.
1330 */
1331 size_t rpc_max_payload(struct rpc_clnt *clnt)
1332 {
1333 size_t ret;
1334
1335 rcu_read_lock();
1336 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1337 rcu_read_unlock();
1338 return ret;
1339 }
1340 EXPORT_SYMBOL_GPL(rpc_max_payload);
1341
1342 /**
1343 * rpc_get_timeout - Get timeout for transport in units of HZ
1344 * @clnt: RPC client to query
1345 */
1346 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1347 {
1348 unsigned long ret;
1349
1350 rcu_read_lock();
1351 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1352 rcu_read_unlock();
1353 return ret;
1354 }
1355 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1356
1357 /**
1358 * rpc_force_rebind - force transport to check that remote port is unchanged
1359 * @clnt: client to rebind
1360 *
1361 */
1362 void rpc_force_rebind(struct rpc_clnt *clnt)
1363 {
1364 if (clnt->cl_autobind) {
1365 rcu_read_lock();
1366 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1367 rcu_read_unlock();
1368 }
1369 }
1370 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1371
1372 /*
1373 * Restart an (async) RPC call from the call_prepare state.
1374 * Usually called from within the exit handler.
1375 */
1376 int
1377 rpc_restart_call_prepare(struct rpc_task *task)
1378 {
1379 if (RPC_ASSASSINATED(task))
1380 return 0;
1381 task->tk_action = call_start;
1382 task->tk_status = 0;
1383 if (task->tk_ops->rpc_call_prepare != NULL)
1384 task->tk_action = rpc_prepare_task;
1385 return 1;
1386 }
1387 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1388
1389 /*
1390 * Restart an (async) RPC call. Usually called from within the
1391 * exit handler.
1392 */
1393 int
1394 rpc_restart_call(struct rpc_task *task)
1395 {
1396 if (RPC_ASSASSINATED(task))
1397 return 0;
1398 task->tk_action = call_start;
1399 task->tk_status = 0;
1400 return 1;
1401 }
1402 EXPORT_SYMBOL_GPL(rpc_restart_call);
1403
1404 #ifdef RPC_DEBUG
1405 static const char *rpc_proc_name(const struct rpc_task *task)
1406 {
1407 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1408
1409 if (proc) {
1410 if (proc->p_name)
1411 return proc->p_name;
1412 else
1413 return "NULL";
1414 } else
1415 return "no proc";
1416 }
1417 #endif
1418
1419 /*
1420 * 0. Initial state
1421 *
1422 * Other FSM states can be visited zero or more times, but
1423 * this state is visited exactly once for each RPC.
1424 */
1425 static void
1426 call_start(struct rpc_task *task)
1427 {
1428 struct rpc_clnt *clnt = task->tk_client;
1429
1430 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1431 clnt->cl_program->name, clnt->cl_vers,
1432 rpc_proc_name(task),
1433 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1434
1435 /* Increment call count */
1436 task->tk_msg.rpc_proc->p_count++;
1437 clnt->cl_stats->rpccnt++;
1438 task->tk_action = call_reserve;
1439 }
1440
1441 /*
1442 * 1. Reserve an RPC call slot
1443 */
1444 static void
1445 call_reserve(struct rpc_task *task)
1446 {
1447 dprint_status(task);
1448
1449 task->tk_status = 0;
1450 task->tk_action = call_reserveresult;
1451 xprt_reserve(task);
1452 }
1453
1454 static void call_retry_reserve(struct rpc_task *task);
1455
1456 /*
1457 * 1b. Grok the result of xprt_reserve()
1458 */
1459 static void
1460 call_reserveresult(struct rpc_task *task)
1461 {
1462 int status = task->tk_status;
1463
1464 dprint_status(task);
1465
1466 /*
1467 * After a call to xprt_reserve(), we must have either
1468 * a request slot or else an error status.
1469 */
1470 task->tk_status = 0;
1471 if (status >= 0) {
1472 if (task->tk_rqstp) {
1473 task->tk_action = call_refresh;
1474 return;
1475 }
1476
1477 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1478 __func__, status);
1479 rpc_exit(task, -EIO);
1480 return;
1481 }
1482
1483 /*
1484 * Even though there was an error, we may have acquired
1485 * a request slot somehow. Make sure not to leak it.
1486 */
1487 if (task->tk_rqstp) {
1488 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1489 __func__, status);
1490 xprt_release(task);
1491 }
1492
1493 switch (status) {
1494 case -ENOMEM:
1495 rpc_delay(task, HZ >> 2);
1496 case -EAGAIN: /* woken up; retry */
1497 task->tk_action = call_retry_reserve;
1498 return;
1499 case -EIO: /* probably a shutdown */
1500 break;
1501 default:
1502 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1503 __func__, status);
1504 break;
1505 }
1506 rpc_exit(task, status);
1507 }
1508
1509 /*
1510 * 1c. Retry reserving an RPC call slot
1511 */
1512 static void
1513 call_retry_reserve(struct rpc_task *task)
1514 {
1515 dprint_status(task);
1516
1517 task->tk_status = 0;
1518 task->tk_action = call_reserveresult;
1519 xprt_retry_reserve(task);
1520 }
1521
1522 /*
1523 * 2. Bind and/or refresh the credentials
1524 */
1525 static void
1526 call_refresh(struct rpc_task *task)
1527 {
1528 dprint_status(task);
1529
1530 task->tk_action = call_refreshresult;
1531 task->tk_status = 0;
1532 task->tk_client->cl_stats->rpcauthrefresh++;
1533 rpcauth_refreshcred(task);
1534 }
1535
1536 /*
1537 * 2a. Process the results of a credential refresh
1538 */
1539 static void
1540 call_refreshresult(struct rpc_task *task)
1541 {
1542 int status = task->tk_status;
1543
1544 dprint_status(task);
1545
1546 task->tk_status = 0;
1547 task->tk_action = call_refresh;
1548 switch (status) {
1549 case 0:
1550 if (rpcauth_uptodatecred(task)) {
1551 task->tk_action = call_allocate;
1552 return;
1553 }
1554 /* Use rate-limiting and a max number of retries if refresh
1555 * had status 0 but failed to update the cred.
1556 */
1557 case -ETIMEDOUT:
1558 rpc_delay(task, 3*HZ);
1559 case -EAGAIN:
1560 status = -EACCES;
1561 case -EKEYEXPIRED:
1562 if (!task->tk_cred_retry)
1563 break;
1564 task->tk_cred_retry--;
1565 dprintk("RPC: %5u %s: retry refresh creds\n",
1566 task->tk_pid, __func__);
1567 return;
1568 }
1569 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1570 task->tk_pid, __func__, status);
1571 rpc_exit(task, status);
1572 }
1573
1574 /*
1575 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1576 * (Note: buffer memory is freed in xprt_release).
1577 */
1578 static void
1579 call_allocate(struct rpc_task *task)
1580 {
1581 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1582 struct rpc_rqst *req = task->tk_rqstp;
1583 struct rpc_xprt *xprt = req->rq_xprt;
1584 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1585
1586 dprint_status(task);
1587
1588 task->tk_status = 0;
1589 task->tk_action = call_bind;
1590
1591 if (req->rq_buffer)
1592 return;
1593
1594 if (proc->p_proc != 0) {
1595 BUG_ON(proc->p_arglen == 0);
1596 if (proc->p_decode != NULL)
1597 BUG_ON(proc->p_replen == 0);
1598 }
1599
1600 /*
1601 * Calculate the size (in quads) of the RPC call
1602 * and reply headers, and convert both values
1603 * to byte sizes.
1604 */
1605 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1606 req->rq_callsize <<= 2;
1607 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1608 req->rq_rcvsize <<= 2;
1609
1610 req->rq_buffer = xprt->ops->buf_alloc(task,
1611 req->rq_callsize + req->rq_rcvsize);
1612 if (req->rq_buffer != NULL)
1613 return;
1614
1615 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1616
1617 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1618 task->tk_action = call_allocate;
1619 rpc_delay(task, HZ>>4);
1620 return;
1621 }
1622
1623 rpc_exit(task, -ERESTARTSYS);
1624 }
1625
1626 static inline int
1627 rpc_task_need_encode(struct rpc_task *task)
1628 {
1629 return task->tk_rqstp->rq_snd_buf.len == 0;
1630 }
1631
1632 static inline void
1633 rpc_task_force_reencode(struct rpc_task *task)
1634 {
1635 task->tk_rqstp->rq_snd_buf.len = 0;
1636 task->tk_rqstp->rq_bytes_sent = 0;
1637 }
1638
1639 static inline void
1640 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1641 {
1642 buf->head[0].iov_base = start;
1643 buf->head[0].iov_len = len;
1644 buf->tail[0].iov_len = 0;
1645 buf->page_len = 0;
1646 buf->flags = 0;
1647 buf->len = 0;
1648 buf->buflen = len;
1649 }
1650
1651 /*
1652 * 3. Encode arguments of an RPC call
1653 */
1654 static void
1655 rpc_xdr_encode(struct rpc_task *task)
1656 {
1657 struct rpc_rqst *req = task->tk_rqstp;
1658 kxdreproc_t encode;
1659 __be32 *p;
1660
1661 dprint_status(task);
1662
1663 rpc_xdr_buf_init(&req->rq_snd_buf,
1664 req->rq_buffer,
1665 req->rq_callsize);
1666 rpc_xdr_buf_init(&req->rq_rcv_buf,
1667 (char *)req->rq_buffer + req->rq_callsize,
1668 req->rq_rcvsize);
1669
1670 p = rpc_encode_header(task);
1671 if (p == NULL) {
1672 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1673 rpc_exit(task, -EIO);
1674 return;
1675 }
1676
1677 encode = task->tk_msg.rpc_proc->p_encode;
1678 if (encode == NULL)
1679 return;
1680
1681 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1682 task->tk_msg.rpc_argp);
1683 }
1684
1685 /*
1686 * 4. Get the server port number if not yet set
1687 */
1688 static void
1689 call_bind(struct rpc_task *task)
1690 {
1691 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1692
1693 dprint_status(task);
1694
1695 task->tk_action = call_connect;
1696 if (!xprt_bound(xprt)) {
1697 task->tk_action = call_bind_status;
1698 task->tk_timeout = xprt->bind_timeout;
1699 xprt->ops->rpcbind(task);
1700 }
1701 }
1702
1703 /*
1704 * 4a. Sort out bind result
1705 */
1706 static void
1707 call_bind_status(struct rpc_task *task)
1708 {
1709 int status = -EIO;
1710
1711 if (task->tk_status >= 0) {
1712 dprint_status(task);
1713 task->tk_status = 0;
1714 task->tk_action = call_connect;
1715 return;
1716 }
1717
1718 trace_rpc_bind_status(task);
1719 switch (task->tk_status) {
1720 case -ENOMEM:
1721 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1722 rpc_delay(task, HZ >> 2);
1723 goto retry_timeout;
1724 case -EACCES:
1725 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1726 "unavailable\n", task->tk_pid);
1727 /* fail immediately if this is an RPC ping */
1728 if (task->tk_msg.rpc_proc->p_proc == 0) {
1729 status = -EOPNOTSUPP;
1730 break;
1731 }
1732 if (task->tk_rebind_retry == 0)
1733 break;
1734 task->tk_rebind_retry--;
1735 rpc_delay(task, 3*HZ);
1736 goto retry_timeout;
1737 case -ETIMEDOUT:
1738 dprintk("RPC: %5u rpcbind request timed out\n",
1739 task->tk_pid);
1740 goto retry_timeout;
1741 case -EPFNOSUPPORT:
1742 /* server doesn't support any rpcbind version we know of */
1743 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1744 task->tk_pid);
1745 break;
1746 case -EPROTONOSUPPORT:
1747 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1748 task->tk_pid);
1749 goto retry_timeout;
1750 case -ECONNREFUSED: /* connection problems */
1751 case -ECONNRESET:
1752 case -ECONNABORTED:
1753 case -ENOTCONN:
1754 case -EHOSTDOWN:
1755 case -EHOSTUNREACH:
1756 case -ENETUNREACH:
1757 case -EPIPE:
1758 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1759 task->tk_pid, task->tk_status);
1760 if (!RPC_IS_SOFTCONN(task)) {
1761 rpc_delay(task, 5*HZ);
1762 goto retry_timeout;
1763 }
1764 status = task->tk_status;
1765 break;
1766 default:
1767 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1768 task->tk_pid, -task->tk_status);
1769 }
1770
1771 rpc_exit(task, status);
1772 return;
1773
1774 retry_timeout:
1775 task->tk_status = 0;
1776 task->tk_action = call_timeout;
1777 }
1778
1779 /*
1780 * 4b. Connect to the RPC server
1781 */
1782 static void
1783 call_connect(struct rpc_task *task)
1784 {
1785 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1786
1787 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1788 task->tk_pid, xprt,
1789 (xprt_connected(xprt) ? "is" : "is not"));
1790
1791 task->tk_action = call_transmit;
1792 if (!xprt_connected(xprt)) {
1793 task->tk_action = call_connect_status;
1794 if (task->tk_status < 0)
1795 return;
1796 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1797 rpc_exit(task, -ENOTCONN);
1798 return;
1799 }
1800 xprt_connect(task);
1801 }
1802 }
1803
1804 /*
1805 * 4c. Sort out connect result
1806 */
1807 static void
1808 call_connect_status(struct rpc_task *task)
1809 {
1810 struct rpc_clnt *clnt = task->tk_client;
1811 int status = task->tk_status;
1812
1813 dprint_status(task);
1814
1815 trace_rpc_connect_status(task, status);
1816 task->tk_status = 0;
1817 switch (status) {
1818 case -ECONNREFUSED:
1819 case -ECONNRESET:
1820 case -ECONNABORTED:
1821 case -ENETUNREACH:
1822 case -EHOSTUNREACH:
1823 if (RPC_IS_SOFTCONN(task))
1824 break;
1825 /* retry with existing socket, after a delay */
1826 rpc_delay(task, 3*HZ);
1827 case -EAGAIN:
1828 /* Check for timeouts before looping back to call_bind */
1829 case -ETIMEDOUT:
1830 task->tk_action = call_timeout;
1831 return;
1832 case 0:
1833 clnt->cl_stats->netreconn++;
1834 task->tk_action = call_transmit;
1835 return;
1836 }
1837 rpc_exit(task, status);
1838 }
1839
1840 /*
1841 * 5. Transmit the RPC request, and wait for reply
1842 */
1843 static void
1844 call_transmit(struct rpc_task *task)
1845 {
1846 int is_retrans = RPC_WAS_SENT(task);
1847
1848 dprint_status(task);
1849
1850 task->tk_action = call_status;
1851 if (task->tk_status < 0)
1852 return;
1853 if (!xprt_prepare_transmit(task))
1854 return;
1855 task->tk_action = call_transmit_status;
1856 /* Encode here so that rpcsec_gss can use correct sequence number. */
1857 if (rpc_task_need_encode(task)) {
1858 rpc_xdr_encode(task);
1859 /* Did the encode result in an error condition? */
1860 if (task->tk_status != 0) {
1861 /* Was the error nonfatal? */
1862 if (task->tk_status == -EAGAIN)
1863 rpc_delay(task, HZ >> 4);
1864 else
1865 rpc_exit(task, task->tk_status);
1866 return;
1867 }
1868 }
1869 xprt_transmit(task);
1870 if (task->tk_status < 0)
1871 return;
1872 if (is_retrans)
1873 task->tk_client->cl_stats->rpcretrans++;
1874 /*
1875 * On success, ensure that we call xprt_end_transmit() before sleeping
1876 * in order to allow access to the socket to other RPC requests.
1877 */
1878 call_transmit_status(task);
1879 if (rpc_reply_expected(task))
1880 return;
1881 task->tk_action = rpc_exit_task;
1882 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1883 }
1884
1885 /*
1886 * 5a. Handle cleanup after a transmission
1887 */
1888 static void
1889 call_transmit_status(struct rpc_task *task)
1890 {
1891 task->tk_action = call_status;
1892
1893 /*
1894 * Common case: success. Force the compiler to put this
1895 * test first.
1896 */
1897 if (task->tk_status == 0) {
1898 xprt_end_transmit(task);
1899 rpc_task_force_reencode(task);
1900 return;
1901 }
1902
1903 switch (task->tk_status) {
1904 case -EAGAIN:
1905 break;
1906 default:
1907 dprint_status(task);
1908 xprt_end_transmit(task);
1909 rpc_task_force_reencode(task);
1910 break;
1911 /*
1912 * Special cases: if we've been waiting on the
1913 * socket's write_space() callback, or if the
1914 * socket just returned a connection error,
1915 * then hold onto the transport lock.
1916 */
1917 case -ECONNREFUSED:
1918 case -EHOSTDOWN:
1919 case -EHOSTUNREACH:
1920 case -ENETUNREACH:
1921 if (RPC_IS_SOFTCONN(task)) {
1922 xprt_end_transmit(task);
1923 rpc_exit(task, task->tk_status);
1924 break;
1925 }
1926 case -ECONNRESET:
1927 case -ECONNABORTED:
1928 case -ENOTCONN:
1929 case -EPIPE:
1930 rpc_task_force_reencode(task);
1931 }
1932 }
1933
1934 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1935 /*
1936 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1937 * addition, disconnect on connectivity errors.
1938 */
1939 static void
1940 call_bc_transmit(struct rpc_task *task)
1941 {
1942 struct rpc_rqst *req = task->tk_rqstp;
1943
1944 if (!xprt_prepare_transmit(task)) {
1945 /*
1946 * Could not reserve the transport. Try again after the
1947 * transport is released.
1948 */
1949 task->tk_status = 0;
1950 task->tk_action = call_bc_transmit;
1951 return;
1952 }
1953
1954 task->tk_action = rpc_exit_task;
1955 if (task->tk_status < 0) {
1956 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1957 "error: %d\n", task->tk_status);
1958 return;
1959 }
1960
1961 xprt_transmit(task);
1962 xprt_end_transmit(task);
1963 dprint_status(task);
1964 switch (task->tk_status) {
1965 case 0:
1966 /* Success */
1967 break;
1968 case -EHOSTDOWN:
1969 case -EHOSTUNREACH:
1970 case -ENETUNREACH:
1971 case -ETIMEDOUT:
1972 /*
1973 * Problem reaching the server. Disconnect and let the
1974 * forechannel reestablish the connection. The server will
1975 * have to retransmit the backchannel request and we'll
1976 * reprocess it. Since these ops are idempotent, there's no
1977 * need to cache our reply at this time.
1978 */
1979 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1980 "error: %d\n", task->tk_status);
1981 xprt_conditional_disconnect(req->rq_xprt,
1982 req->rq_connect_cookie);
1983 break;
1984 default:
1985 /*
1986 * We were unable to reply and will have to drop the
1987 * request. The server should reconnect and retransmit.
1988 */
1989 WARN_ON_ONCE(task->tk_status == -EAGAIN);
1990 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1991 "error: %d\n", task->tk_status);
1992 break;
1993 }
1994 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1995 }
1996 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1997
1998 /*
1999 * 6. Sort out the RPC call status
2000 */
2001 static void
2002 call_status(struct rpc_task *task)
2003 {
2004 struct rpc_clnt *clnt = task->tk_client;
2005 struct rpc_rqst *req = task->tk_rqstp;
2006 int status;
2007
2008 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
2009 task->tk_status = req->rq_reply_bytes_recvd;
2010
2011 dprint_status(task);
2012
2013 status = task->tk_status;
2014 if (status >= 0) {
2015 task->tk_action = call_decode;
2016 return;
2017 }
2018
2019 trace_rpc_call_status(task);
2020 task->tk_status = 0;
2021 switch(status) {
2022 case -EHOSTDOWN:
2023 case -EHOSTUNREACH:
2024 case -ENETUNREACH:
2025 if (RPC_IS_SOFTCONN(task)) {
2026 rpc_exit(task, status);
2027 break;
2028 }
2029 /*
2030 * Delay any retries for 3 seconds, then handle as if it
2031 * were a timeout.
2032 */
2033 rpc_delay(task, 3*HZ);
2034 case -ETIMEDOUT:
2035 task->tk_action = call_timeout;
2036 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2037 && task->tk_client->cl_discrtry)
2038 xprt_conditional_disconnect(req->rq_xprt,
2039 req->rq_connect_cookie);
2040 break;
2041 case -ECONNREFUSED:
2042 case -ECONNRESET:
2043 case -ECONNABORTED:
2044 rpc_force_rebind(clnt);
2045 rpc_delay(task, 3*HZ);
2046 case -EPIPE:
2047 case -ENOTCONN:
2048 task->tk_action = call_bind;
2049 break;
2050 case -EAGAIN:
2051 task->tk_action = call_transmit;
2052 break;
2053 case -EIO:
2054 /* shutdown or soft timeout */
2055 rpc_exit(task, status);
2056 break;
2057 default:
2058 if (clnt->cl_chatty)
2059 printk("%s: RPC call returned error %d\n",
2060 clnt->cl_program->name, -status);
2061 rpc_exit(task, status);
2062 }
2063 }
2064
2065 /*
2066 * 6a. Handle RPC timeout
2067 * We do not release the request slot, so we keep using the
2068 * same XID for all retransmits.
2069 */
2070 static void
2071 call_timeout(struct rpc_task *task)
2072 {
2073 struct rpc_clnt *clnt = task->tk_client;
2074
2075 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2076 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2077 goto retry;
2078 }
2079
2080 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2081 task->tk_timeouts++;
2082
2083 if (RPC_IS_SOFTCONN(task)) {
2084 rpc_exit(task, -ETIMEDOUT);
2085 return;
2086 }
2087 if (RPC_IS_SOFT(task)) {
2088 if (clnt->cl_chatty) {
2089 rcu_read_lock();
2090 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2091 clnt->cl_program->name,
2092 rcu_dereference(clnt->cl_xprt)->servername);
2093 rcu_read_unlock();
2094 }
2095 if (task->tk_flags & RPC_TASK_TIMEOUT)
2096 rpc_exit(task, -ETIMEDOUT);
2097 else
2098 rpc_exit(task, -EIO);
2099 return;
2100 }
2101
2102 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2103 task->tk_flags |= RPC_CALL_MAJORSEEN;
2104 if (clnt->cl_chatty) {
2105 rcu_read_lock();
2106 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2107 clnt->cl_program->name,
2108 rcu_dereference(clnt->cl_xprt)->servername);
2109 rcu_read_unlock();
2110 }
2111 }
2112 rpc_force_rebind(clnt);
2113 /*
2114 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2115 * event? RFC2203 requires the server to drop all such requests.
2116 */
2117 rpcauth_invalcred(task);
2118
2119 retry:
2120 task->tk_action = call_bind;
2121 task->tk_status = 0;
2122 }
2123
2124 /*
2125 * 7. Decode the RPC reply
2126 */
2127 static void
2128 call_decode(struct rpc_task *task)
2129 {
2130 struct rpc_clnt *clnt = task->tk_client;
2131 struct rpc_rqst *req = task->tk_rqstp;
2132 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2133 __be32 *p;
2134
2135 dprint_status(task);
2136
2137 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2138 if (clnt->cl_chatty) {
2139 rcu_read_lock();
2140 printk(KERN_NOTICE "%s: server %s OK\n",
2141 clnt->cl_program->name,
2142 rcu_dereference(clnt->cl_xprt)->servername);
2143 rcu_read_unlock();
2144 }
2145 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2146 }
2147
2148 /*
2149 * Ensure that we see all writes made by xprt_complete_rqst()
2150 * before it changed req->rq_reply_bytes_recvd.
2151 */
2152 smp_rmb();
2153 req->rq_rcv_buf.len = req->rq_private_buf.len;
2154
2155 /* Check that the softirq receive buffer is valid */
2156 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2157 sizeof(req->rq_rcv_buf)) != 0);
2158
2159 if (req->rq_rcv_buf.len < 12) {
2160 if (!RPC_IS_SOFT(task)) {
2161 task->tk_action = call_bind;
2162 goto out_retry;
2163 }
2164 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2165 clnt->cl_program->name, task->tk_status);
2166 task->tk_action = call_timeout;
2167 goto out_retry;
2168 }
2169
2170 p = rpc_verify_header(task);
2171 if (IS_ERR(p)) {
2172 if (p == ERR_PTR(-EAGAIN))
2173 goto out_retry;
2174 return;
2175 }
2176
2177 task->tk_action = rpc_exit_task;
2178
2179 if (decode) {
2180 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2181 task->tk_msg.rpc_resp);
2182 }
2183 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2184 task->tk_status);
2185 return;
2186 out_retry:
2187 task->tk_status = 0;
2188 /* Note: rpc_verify_header() may have freed the RPC slot */
2189 if (task->tk_rqstp == req) {
2190 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2191 if (task->tk_client->cl_discrtry)
2192 xprt_conditional_disconnect(req->rq_xprt,
2193 req->rq_connect_cookie);
2194 }
2195 }
2196
2197 static __be32 *
2198 rpc_encode_header(struct rpc_task *task)
2199 {
2200 struct rpc_clnt *clnt = task->tk_client;
2201 struct rpc_rqst *req = task->tk_rqstp;
2202 __be32 *p = req->rq_svec[0].iov_base;
2203
2204 /* FIXME: check buffer size? */
2205
2206 p = xprt_skip_transport_header(req->rq_xprt, p);
2207 *p++ = req->rq_xid; /* XID */
2208 *p++ = htonl(RPC_CALL); /* CALL */
2209 *p++ = htonl(RPC_VERSION); /* RPC version */
2210 *p++ = htonl(clnt->cl_prog); /* program number */
2211 *p++ = htonl(clnt->cl_vers); /* program version */
2212 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2213 p = rpcauth_marshcred(task, p);
2214 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2215 return p;
2216 }
2217
2218 static __be32 *
2219 rpc_verify_header(struct rpc_task *task)
2220 {
2221 struct rpc_clnt *clnt = task->tk_client;
2222 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2223 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2224 __be32 *p = iov->iov_base;
2225 u32 n;
2226 int error = -EACCES;
2227
2228 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2229 /* RFC-1014 says that the representation of XDR data must be a
2230 * multiple of four bytes
2231 * - if it isn't pointer subtraction in the NFS client may give
2232 * undefined results
2233 */
2234 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2235 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2236 task->tk_rqstp->rq_rcv_buf.len);
2237 error = -EIO;
2238 goto out_err;
2239 }
2240 if ((len -= 3) < 0)
2241 goto out_overflow;
2242
2243 p += 1; /* skip XID */
2244 if ((n = ntohl(*p++)) != RPC_REPLY) {
2245 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2246 task->tk_pid, __func__, n);
2247 error = -EIO;
2248 goto out_garbage;
2249 }
2250
2251 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2252 if (--len < 0)
2253 goto out_overflow;
2254 switch ((n = ntohl(*p++))) {
2255 case RPC_AUTH_ERROR:
2256 break;
2257 case RPC_MISMATCH:
2258 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2259 task->tk_pid, __func__);
2260 error = -EPROTONOSUPPORT;
2261 goto out_err;
2262 default:
2263 dprintk("RPC: %5u %s: RPC call rejected, "
2264 "unknown error: %x\n",
2265 task->tk_pid, __func__, n);
2266 error = -EIO;
2267 goto out_err;
2268 }
2269 if (--len < 0)
2270 goto out_overflow;
2271 switch ((n = ntohl(*p++))) {
2272 case RPC_AUTH_REJECTEDCRED:
2273 case RPC_AUTH_REJECTEDVERF:
2274 case RPCSEC_GSS_CREDPROBLEM:
2275 case RPCSEC_GSS_CTXPROBLEM:
2276 if (!task->tk_cred_retry)
2277 break;
2278 task->tk_cred_retry--;
2279 dprintk("RPC: %5u %s: retry stale creds\n",
2280 task->tk_pid, __func__);
2281 rpcauth_invalcred(task);
2282 /* Ensure we obtain a new XID! */
2283 xprt_release(task);
2284 task->tk_action = call_reserve;
2285 goto out_retry;
2286 case RPC_AUTH_BADCRED:
2287 case RPC_AUTH_BADVERF:
2288 /* possibly garbled cred/verf? */
2289 if (!task->tk_garb_retry)
2290 break;
2291 task->tk_garb_retry--;
2292 dprintk("RPC: %5u %s: retry garbled creds\n",
2293 task->tk_pid, __func__);
2294 task->tk_action = call_bind;
2295 goto out_retry;
2296 case RPC_AUTH_TOOWEAK:
2297 rcu_read_lock();
2298 printk(KERN_NOTICE "RPC: server %s requires stronger "
2299 "authentication.\n",
2300 rcu_dereference(clnt->cl_xprt)->servername);
2301 rcu_read_unlock();
2302 break;
2303 default:
2304 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2305 task->tk_pid, __func__, n);
2306 error = -EIO;
2307 }
2308 dprintk("RPC: %5u %s: call rejected %d\n",
2309 task->tk_pid, __func__, n);
2310 goto out_err;
2311 }
2312 p = rpcauth_checkverf(task, p);
2313 if (IS_ERR(p)) {
2314 error = PTR_ERR(p);
2315 dprintk("RPC: %5u %s: auth check failed with %d\n",
2316 task->tk_pid, __func__, error);
2317 goto out_garbage; /* bad verifier, retry */
2318 }
2319 len = p - (__be32 *)iov->iov_base - 1;
2320 if (len < 0)
2321 goto out_overflow;
2322 switch ((n = ntohl(*p++))) {
2323 case RPC_SUCCESS:
2324 return p;
2325 case RPC_PROG_UNAVAIL:
2326 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2327 "by server %s\n", task->tk_pid, __func__,
2328 (unsigned int)clnt->cl_prog,
2329 rcu_dereference(clnt->cl_xprt)->servername);
2330 error = -EPFNOSUPPORT;
2331 goto out_err;
2332 case RPC_PROG_MISMATCH:
2333 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2334 "by server %s\n", task->tk_pid, __func__,
2335 (unsigned int)clnt->cl_prog,
2336 (unsigned int)clnt->cl_vers,
2337 rcu_dereference(clnt->cl_xprt)->servername);
2338 error = -EPROTONOSUPPORT;
2339 goto out_err;
2340 case RPC_PROC_UNAVAIL:
2341 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2342 "version %u on server %s\n",
2343 task->tk_pid, __func__,
2344 rpc_proc_name(task),
2345 clnt->cl_prog, clnt->cl_vers,
2346 rcu_dereference(clnt->cl_xprt)->servername);
2347 error = -EOPNOTSUPP;
2348 goto out_err;
2349 case RPC_GARBAGE_ARGS:
2350 dprintk("RPC: %5u %s: server saw garbage\n",
2351 task->tk_pid, __func__);
2352 break; /* retry */
2353 default:
2354 dprintk("RPC: %5u %s: server accept status: %x\n",
2355 task->tk_pid, __func__, n);
2356 /* Also retry */
2357 }
2358
2359 out_garbage:
2360 clnt->cl_stats->rpcgarbage++;
2361 if (task->tk_garb_retry) {
2362 task->tk_garb_retry--;
2363 dprintk("RPC: %5u %s: retrying\n",
2364 task->tk_pid, __func__);
2365 task->tk_action = call_bind;
2366 out_retry:
2367 return ERR_PTR(-EAGAIN);
2368 }
2369 out_err:
2370 rpc_exit(task, error);
2371 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2372 __func__, error);
2373 return ERR_PTR(error);
2374 out_overflow:
2375 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2376 __func__);
2377 goto out_garbage;
2378 }
2379
2380 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2381 {
2382 }
2383
2384 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2385 {
2386 return 0;
2387 }
2388
2389 static struct rpc_procinfo rpcproc_null = {
2390 .p_encode = rpcproc_encode_null,
2391 .p_decode = rpcproc_decode_null,
2392 };
2393
2394 static int rpc_ping(struct rpc_clnt *clnt)
2395 {
2396 struct rpc_message msg = {
2397 .rpc_proc = &rpcproc_null,
2398 };
2399 int err;
2400 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2401 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2402 put_rpccred(msg.rpc_cred);
2403 return err;
2404 }
2405
2406 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2407 {
2408 struct rpc_message msg = {
2409 .rpc_proc = &rpcproc_null,
2410 .rpc_cred = cred,
2411 };
2412 struct rpc_task_setup task_setup_data = {
2413 .rpc_client = clnt,
2414 .rpc_message = &msg,
2415 .callback_ops = &rpc_default_ops,
2416 .flags = flags,
2417 };
2418 return rpc_run_task(&task_setup_data);
2419 }
2420 EXPORT_SYMBOL_GPL(rpc_call_null);
2421
2422 #ifdef RPC_DEBUG
2423 static void rpc_show_header(void)
2424 {
2425 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2426 "-timeout ---ops--\n");
2427 }
2428
2429 static void rpc_show_task(const struct rpc_clnt *clnt,
2430 const struct rpc_task *task)
2431 {
2432 const char *rpc_waitq = "none";
2433
2434 if (RPC_IS_QUEUED(task))
2435 rpc_waitq = rpc_qname(task->tk_waitqueue);
2436
2437 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2438 task->tk_pid, task->tk_flags, task->tk_status,
2439 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2440 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2441 task->tk_action, rpc_waitq);
2442 }
2443
2444 void rpc_show_tasks(struct net *net)
2445 {
2446 struct rpc_clnt *clnt;
2447 struct rpc_task *task;
2448 int header = 0;
2449 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2450
2451 spin_lock(&sn->rpc_client_lock);
2452 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2453 spin_lock(&clnt->cl_lock);
2454 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2455 if (!header) {
2456 rpc_show_header();
2457 header++;
2458 }
2459 rpc_show_task(clnt, task);
2460 }
2461 spin_unlock(&clnt->cl_lock);
2462 }
2463 spin_unlock(&sn->rpc_client_lock);
2464 }
2465 #endif
Linux with added FPC-III support