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fix a kmap leak in virtio_console
[linux/fpc-iii.git] / net / sunrpc / clnt.c
blob0edada973434e4df883f63a85173f4a7a1de0885
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 static int rpc_alloc_clid(struct rpc_clnt *clnt)
340 {
341 int clid;
342
343 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
344 if (clid < 0)
345 return clid;
346 clnt->cl_clid = clid;
347 return 0;
348 }
349
350 static void rpc_free_clid(struct rpc_clnt *clnt)
351 {
352 ida_simple_remove(&rpc_clids, clnt->cl_clid);
353 }
354
355 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
356 struct rpc_xprt *xprt,
357 struct rpc_clnt *parent)
358 {
359 const struct rpc_program *program = args->program;
360 const struct rpc_version *version;
361 struct rpc_clnt *clnt = NULL;
362 const struct rpc_timeout *timeout;
363 int err;
364
365 /* sanity check the name before trying to print it */
366 dprintk("RPC: creating %s client for %s (xprt %p)\n",
367 program->name, args->servername, xprt);
368
369 err = rpciod_up();
370 if (err)
371 goto out_no_rpciod;
372
373 err = -EINVAL;
374 if (args->version >= program->nrvers)
375 goto out_err;
376 version = program->version[args->version];
377 if (version == NULL)
378 goto out_err;
379
380 err = -ENOMEM;
381 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
382 if (!clnt)
383 goto out_err;
384 clnt->cl_parent = parent ? : clnt;
385
386 err = rpc_alloc_clid(clnt);
387 if (err)
388 goto out_no_clid;
389
390 clnt->cl_procinfo = version->procs;
391 clnt->cl_maxproc = version->nrprocs;
392 clnt->cl_prog = args->prognumber ? : program->number;
393 clnt->cl_vers = version->number;
394 clnt->cl_stats = program->stats;
395 clnt->cl_metrics = rpc_alloc_iostats(clnt);
396 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
397 err = -ENOMEM;
398 if (clnt->cl_metrics == NULL)
399 goto out_no_stats;
400 clnt->cl_program = program;
401 INIT_LIST_HEAD(&clnt->cl_tasks);
402 spin_lock_init(&clnt->cl_lock);
403
404 timeout = xprt->timeout;
405 if (args->timeout != NULL) {
406 memcpy(&clnt->cl_timeout_default, args->timeout,
407 sizeof(clnt->cl_timeout_default));
408 timeout = &clnt->cl_timeout_default;
409 }
410
411 rpc_clnt_set_transport(clnt, xprt, timeout);
412
413 clnt->cl_rtt = &clnt->cl_rtt_default;
414 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
415
416 atomic_set(&clnt->cl_count, 1);
417
418 /* save the nodename */
419 rpc_clnt_set_nodename(clnt, utsname()->nodename);
420
421 err = rpc_client_register(clnt, args->authflavor, args->client_name);
422 if (err)
423 goto out_no_path;
424 if (parent)
425 atomic_inc(&parent->cl_count);
426 return clnt;
427
428 out_no_path:
429 rpc_free_iostats(clnt->cl_metrics);
430 out_no_stats:
431 rpc_free_clid(clnt);
432 out_no_clid:
433 kfree(clnt);
434 out_err:
435 rpciod_down();
436 out_no_rpciod:
437 xprt_put(xprt);
438 return ERR_PTR(err);
439 }
440
441 /**
442 * rpc_create - create an RPC client and transport with one call
443 * @args: rpc_clnt create argument structure
444 *
445 * Creates and initializes an RPC transport and an RPC client.
446 *
447 * It can ping the server in order to determine if it is up, and to see if
448 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
449 * this behavior so asynchronous tasks can also use rpc_create.
450 */
451 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
452 {
453 struct rpc_xprt *xprt;
454 struct rpc_clnt *clnt;
455 struct xprt_create xprtargs = {
456 .net = args->net,
457 .ident = args->protocol,
458 .srcaddr = args->saddress,
459 .dstaddr = args->address,
460 .addrlen = args->addrsize,
461 .servername = args->servername,
462 .bc_xprt = args->bc_xprt,
463 };
464 char servername[48];
465
466 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
467 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
468 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
469 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
470 /*
471 * If the caller chooses not to specify a hostname, whip
472 * up a string representation of the passed-in address.
473 */
474 if (xprtargs.servername == NULL) {
475 struct sockaddr_un *sun =
476 (struct sockaddr_un *)args->address;
477 struct sockaddr_in *sin =
478 (struct sockaddr_in *)args->address;
479 struct sockaddr_in6 *sin6 =
480 (struct sockaddr_in6 *)args->address;
481
482 servername[0] = '\0';
483 switch (args->address->sa_family) {
484 case AF_LOCAL:
485 snprintf(servername, sizeof(servername), "%s",
486 sun->sun_path);
487 break;
488 case AF_INET:
489 snprintf(servername, sizeof(servername), "%pI4",
490 &sin->sin_addr.s_addr);
491 break;
492 case AF_INET6:
493 snprintf(servername, sizeof(servername), "%pI6",
494 &sin6->sin6_addr);
495 break;
496 default:
497 /* caller wants default server name, but
498 * address family isn't recognized. */
499 return ERR_PTR(-EINVAL);
500 }
501 xprtargs.servername = servername;
502 }
503
504 xprt = xprt_create_transport(&xprtargs);
505 if (IS_ERR(xprt))
506 return (struct rpc_clnt *)xprt;
507
508 /*
509 * By default, kernel RPC client connects from a reserved port.
510 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
511 * but it is always enabled for rpciod, which handles the connect
512 * operation.
513 */
514 xprt->resvport = 1;
515 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
516 xprt->resvport = 0;
517
518 clnt = rpc_new_client(args, xprt, NULL);
519 if (IS_ERR(clnt))
520 return clnt;
521
522 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
523 int err = rpc_ping(clnt);
524 if (err != 0) {
525 rpc_shutdown_client(clnt);
526 return ERR_PTR(err);
527 }
528 }
529
530 clnt->cl_softrtry = 1;
531 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
532 clnt->cl_softrtry = 0;
533
534 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
535 clnt->cl_autobind = 1;
536 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
537 clnt->cl_discrtry = 1;
538 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
539 clnt->cl_chatty = 1;
540
541 return clnt;
542 }
543 EXPORT_SYMBOL_GPL(rpc_create);
544
545 /*
546 * This function clones the RPC client structure. It allows us to share the
547 * same transport while varying parameters such as the authentication
548 * flavour.
549 */
550 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
551 struct rpc_clnt *clnt)
552 {
553 struct rpc_xprt *xprt;
554 struct rpc_clnt *new;
555 int err;
556
557 err = -ENOMEM;
558 rcu_read_lock();
559 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
560 rcu_read_unlock();
561 if (xprt == NULL)
562 goto out_err;
563 args->servername = xprt->servername;
564
565 new = rpc_new_client(args, xprt, clnt);
566 if (IS_ERR(new)) {
567 err = PTR_ERR(new);
568 goto out_err;
569 }
570
571 /* Turn off autobind on clones */
572 new->cl_autobind = 0;
573 new->cl_softrtry = clnt->cl_softrtry;
574 new->cl_discrtry = clnt->cl_discrtry;
575 new->cl_chatty = clnt->cl_chatty;
576 return new;
577
578 out_err:
579 dprintk("RPC: %s: returned error %d\n", __func__, err);
580 return ERR_PTR(err);
581 }
582
583 /**
584 * rpc_clone_client - Clone an RPC client structure
585 *
586 * @clnt: RPC client whose parameters are copied
587 *
588 * Returns a fresh RPC client or an ERR_PTR.
589 */
590 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
591 {
592 struct rpc_create_args args = {
593 .program = clnt->cl_program,
594 .prognumber = clnt->cl_prog,
595 .version = clnt->cl_vers,
596 .authflavor = clnt->cl_auth->au_flavor,
597 };
598 return __rpc_clone_client(&args, clnt);
599 }
600 EXPORT_SYMBOL_GPL(rpc_clone_client);
601
602 /**
603 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
604 *
605 * @clnt: RPC client whose parameters are copied
606 * @flavor: security flavor for new client
607 *
608 * Returns a fresh RPC client or an ERR_PTR.
609 */
610 struct rpc_clnt *
611 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
612 {
613 struct rpc_create_args args = {
614 .program = clnt->cl_program,
615 .prognumber = clnt->cl_prog,
616 .version = clnt->cl_vers,
617 .authflavor = flavor,
618 };
619 return __rpc_clone_client(&args, clnt);
620 }
621 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
622
623 /**
624 * rpc_switch_client_transport: switch the RPC transport on the fly
625 * @clnt: pointer to a struct rpc_clnt
626 * @args: pointer to the new transport arguments
627 * @timeout: pointer to the new timeout parameters
628 *
629 * This function allows the caller to switch the RPC transport for the
630 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
631 * server, for instance. It assumes that the caller has ensured that
632 * there are no active RPC tasks by using some form of locking.
633 *
634 * Returns zero if "clnt" is now using the new xprt. Otherwise a
635 * negative errno is returned, and "clnt" continues to use the old
636 * xprt.
637 */
638 int rpc_switch_client_transport(struct rpc_clnt *clnt,
639 struct xprt_create *args,
640 const struct rpc_timeout *timeout)
641 {
642 const struct rpc_timeout *old_timeo;
643 rpc_authflavor_t pseudoflavor;
644 struct rpc_xprt *xprt, *old;
645 struct rpc_clnt *parent;
646 int err;
647
648 xprt = xprt_create_transport(args);
649 if (IS_ERR(xprt)) {
650 dprintk("RPC: failed to create new xprt for clnt %p\n",
651 clnt);
652 return PTR_ERR(xprt);
653 }
654
655 pseudoflavor = clnt->cl_auth->au_flavor;
656
657 old_timeo = clnt->cl_timeout;
658 old = rpc_clnt_set_transport(clnt, xprt, timeout);
659
660 rpc_unregister_client(clnt);
661 __rpc_clnt_remove_pipedir(clnt);
662
663 /*
664 * A new transport was created. "clnt" therefore
665 * becomes the root of a new cl_parent tree. clnt's
666 * children, if it has any, still point to the old xprt.
667 */
668 parent = clnt->cl_parent;
669 clnt->cl_parent = clnt;
670
671 /*
672 * The old rpc_auth cache cannot be re-used. GSS
673 * contexts in particular are between a single
674 * client and server.
675 */
676 err = rpc_client_register(clnt, pseudoflavor, NULL);
677 if (err)
678 goto out_revert;
679
680 synchronize_rcu();
681 if (parent != clnt)
682 rpc_release_client(parent);
683 xprt_put(old);
684 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
685 return 0;
686
687 out_revert:
688 rpc_clnt_set_transport(clnt, old, old_timeo);
689 clnt->cl_parent = parent;
690 rpc_client_register(clnt, pseudoflavor, NULL);
691 xprt_put(xprt);
692 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
693 return err;
694 }
695 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
696
697 /*
698 * Kill all tasks for the given client.
699 * XXX: kill their descendants as well?
700 */
701 void rpc_killall_tasks(struct rpc_clnt *clnt)
702 {
703 struct rpc_task *rovr;
704
705
706 if (list_empty(&clnt->cl_tasks))
707 return;
708 dprintk("RPC: killing all tasks for client %p\n", clnt);
709 /*
710 * Spin lock all_tasks to prevent changes...
711 */
712 spin_lock(&clnt->cl_lock);
713 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
714 if (!RPC_IS_ACTIVATED(rovr))
715 continue;
716 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
717 rovr->tk_flags |= RPC_TASK_KILLED;
718 rpc_exit(rovr, -EIO);
719 if (RPC_IS_QUEUED(rovr))
720 rpc_wake_up_queued_task(rovr->tk_waitqueue,
721 rovr);
722 }
723 }
724 spin_unlock(&clnt->cl_lock);
725 }
726 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
727
728 /*
729 * Properly shut down an RPC client, terminating all outstanding
730 * requests.
731 */
732 void rpc_shutdown_client(struct rpc_clnt *clnt)
733 {
734 might_sleep();
735
736 dprintk_rcu("RPC: shutting down %s client for %s\n",
737 clnt->cl_program->name,
738 rcu_dereference(clnt->cl_xprt)->servername);
739
740 while (!list_empty(&clnt->cl_tasks)) {
741 rpc_killall_tasks(clnt);
742 wait_event_timeout(destroy_wait,
743 list_empty(&clnt->cl_tasks), 1*HZ);
744 }
745
746 rpc_release_client(clnt);
747 }
748 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
749
750 /*
751 * Free an RPC client
752 */
753 static struct rpc_clnt *
754 rpc_free_client(struct rpc_clnt *clnt)
755 {
756 struct rpc_clnt *parent = NULL;
757
758 dprintk_rcu("RPC: destroying %s client for %s\n",
759 clnt->cl_program->name,
760 rcu_dereference(clnt->cl_xprt)->servername);
761 if (clnt->cl_parent != clnt)
762 parent = clnt->cl_parent;
763 rpc_clnt_remove_pipedir(clnt);
764 rpc_unregister_client(clnt);
765 rpc_free_iostats(clnt->cl_metrics);
766 clnt->cl_metrics = NULL;
767 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
768 rpciod_down();
769 rpc_free_clid(clnt);
770 kfree(clnt);
771 return parent;
772 }
773
774 /*
775 * Free an RPC client
776 */
777 static struct rpc_clnt *
778 rpc_free_auth(struct rpc_clnt *clnt)
779 {
780 if (clnt->cl_auth == NULL)
781 return rpc_free_client(clnt);
782
783 /*
784 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
785 * release remaining GSS contexts. This mechanism ensures
786 * that it can do so safely.
787 */
788 atomic_inc(&clnt->cl_count);
789 rpcauth_release(clnt->cl_auth);
790 clnt->cl_auth = NULL;
791 if (atomic_dec_and_test(&clnt->cl_count))
792 return rpc_free_client(clnt);
793 return NULL;
794 }
795
796 /*
797 * Release reference to the RPC client
798 */
799 void
800 rpc_release_client(struct rpc_clnt *clnt)
801 {
802 dprintk("RPC: rpc_release_client(%p)\n", clnt);
803
804 do {
805 if (list_empty(&clnt->cl_tasks))
806 wake_up(&destroy_wait);
807 if (!atomic_dec_and_test(&clnt->cl_count))
808 break;
809 clnt = rpc_free_auth(clnt);
810 } while (clnt != NULL);
811 }
812 EXPORT_SYMBOL_GPL(rpc_release_client);
813
814 /**
815 * rpc_bind_new_program - bind a new RPC program to an existing client
816 * @old: old rpc_client
817 * @program: rpc program to set
818 * @vers: rpc program version
819 *
820 * Clones the rpc client and sets up a new RPC program. This is mainly
821 * of use for enabling different RPC programs to share the same transport.
822 * The Sun NFSv2/v3 ACL protocol can do this.
823 */
824 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
825 const struct rpc_program *program,
826 u32 vers)
827 {
828 struct rpc_create_args args = {
829 .program = program,
830 .prognumber = program->number,
831 .version = vers,
832 .authflavor = old->cl_auth->au_flavor,
833 };
834 struct rpc_clnt *clnt;
835 int err;
836
837 clnt = __rpc_clone_client(&args, old);
838 if (IS_ERR(clnt))
839 goto out;
840 err = rpc_ping(clnt);
841 if (err != 0) {
842 rpc_shutdown_client(clnt);
843 clnt = ERR_PTR(err);
844 }
845 out:
846 return clnt;
847 }
848 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
849
850 void rpc_task_release_client(struct rpc_task *task)
851 {
852 struct rpc_clnt *clnt = task->tk_client;
853
854 if (clnt != NULL) {
855 /* Remove from client task list */
856 spin_lock(&clnt->cl_lock);
857 list_del(&task->tk_task);
858 spin_unlock(&clnt->cl_lock);
859 task->tk_client = NULL;
860
861 rpc_release_client(clnt);
862 }
863 }
864
865 static
866 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
867 {
868 if (clnt != NULL) {
869 rpc_task_release_client(task);
870 task->tk_client = clnt;
871 atomic_inc(&clnt->cl_count);
872 if (clnt->cl_softrtry)
873 task->tk_flags |= RPC_TASK_SOFT;
874 if (clnt->cl_noretranstimeo)
875 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
876 if (sk_memalloc_socks()) {
877 struct rpc_xprt *xprt;
878
879 rcu_read_lock();
880 xprt = rcu_dereference(clnt->cl_xprt);
881 if (xprt->swapper)
882 task->tk_flags |= RPC_TASK_SWAPPER;
883 rcu_read_unlock();
884 }
885 /* Add to the client's list of all tasks */
886 spin_lock(&clnt->cl_lock);
887 list_add_tail(&task->tk_task, &clnt->cl_tasks);
888 spin_unlock(&clnt->cl_lock);
889 }
890 }
891
892 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
893 {
894 rpc_task_release_client(task);
895 rpc_task_set_client(task, clnt);
896 }
897 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
898
899
900 static void
901 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
902 {
903 if (msg != NULL) {
904 task->tk_msg.rpc_proc = msg->rpc_proc;
905 task->tk_msg.rpc_argp = msg->rpc_argp;
906 task->tk_msg.rpc_resp = msg->rpc_resp;
907 if (msg->rpc_cred != NULL)
908 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
909 }
910 }
911
912 /*
913 * Default callback for async RPC calls
914 */
915 static void
916 rpc_default_callback(struct rpc_task *task, void *data)
917 {
918 }
919
920 static const struct rpc_call_ops rpc_default_ops = {
921 .rpc_call_done = rpc_default_callback,
922 };
923
924 /**
925 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
926 * @task_setup_data: pointer to task initialisation data
927 */
928 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
929 {
930 struct rpc_task *task;
931
932 task = rpc_new_task(task_setup_data);
933 if (IS_ERR(task))
934 goto out;
935
936 rpc_task_set_client(task, task_setup_data->rpc_client);
937 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
938
939 if (task->tk_action == NULL)
940 rpc_call_start(task);
941
942 atomic_inc(&task->tk_count);
943 rpc_execute(task);
944 out:
945 return task;
946 }
947 EXPORT_SYMBOL_GPL(rpc_run_task);
948
949 /**
950 * rpc_call_sync - Perform a synchronous RPC call
951 * @clnt: pointer to RPC client
952 * @msg: RPC call parameters
953 * @flags: RPC call flags
954 */
955 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
956 {
957 struct rpc_task *task;
958 struct rpc_task_setup task_setup_data = {
959 .rpc_client = clnt,
960 .rpc_message = msg,
961 .callback_ops = &rpc_default_ops,
962 .flags = flags,
963 };
964 int status;
965
966 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
967 if (flags & RPC_TASK_ASYNC) {
968 rpc_release_calldata(task_setup_data.callback_ops,
969 task_setup_data.callback_data);
970 return -EINVAL;
971 }
972
973 task = rpc_run_task(&task_setup_data);
974 if (IS_ERR(task))
975 return PTR_ERR(task);
976 status = task->tk_status;
977 rpc_put_task(task);
978 return status;
979 }
980 EXPORT_SYMBOL_GPL(rpc_call_sync);
981
982 /**
983 * rpc_call_async - Perform an asynchronous RPC call
984 * @clnt: pointer to RPC client
985 * @msg: RPC call parameters
986 * @flags: RPC call flags
987 * @tk_ops: RPC call ops
988 * @data: user call data
989 */
990 int
991 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
992 const struct rpc_call_ops *tk_ops, void *data)
993 {
994 struct rpc_task *task;
995 struct rpc_task_setup task_setup_data = {
996 .rpc_client = clnt,
997 .rpc_message = msg,
998 .callback_ops = tk_ops,
999 .callback_data = data,
1000 .flags = flags|RPC_TASK_ASYNC,
1001 };
1002
1003 task = rpc_run_task(&task_setup_data);
1004 if (IS_ERR(task))
1005 return PTR_ERR(task);
1006 rpc_put_task(task);
1007 return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(rpc_call_async);
1010
1011 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1012 /**
1013 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1014 * rpc_execute against it
1015 * @req: RPC request
1016 * @tk_ops: RPC call ops
1017 */
1018 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1019 const struct rpc_call_ops *tk_ops)
1020 {
1021 struct rpc_task *task;
1022 struct xdr_buf *xbufp = &req->rq_snd_buf;
1023 struct rpc_task_setup task_setup_data = {
1024 .callback_ops = tk_ops,
1025 };
1026
1027 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1028 /*
1029 * Create an rpc_task to send the data
1030 */
1031 task = rpc_new_task(&task_setup_data);
1032 if (IS_ERR(task)) {
1033 xprt_free_bc_request(req);
1034 goto out;
1035 }
1036 task->tk_rqstp = req;
1037
1038 /*
1039 * Set up the xdr_buf length.
1040 * This also indicates that the buffer is XDR encoded already.
1041 */
1042 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1043 xbufp->tail[0].iov_len;
1044
1045 task->tk_action = call_bc_transmit;
1046 atomic_inc(&task->tk_count);
1047 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1048 rpc_execute(task);
1049
1050 out:
1051 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1052 return task;
1053 }
1054 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1055
1056 void
1057 rpc_call_start(struct rpc_task *task)
1058 {
1059 task->tk_action = call_start;
1060 }
1061 EXPORT_SYMBOL_GPL(rpc_call_start);
1062
1063 /**
1064 * rpc_peeraddr - extract remote peer address from clnt's xprt
1065 * @clnt: RPC client structure
1066 * @buf: target buffer
1067 * @bufsize: length of target buffer
1068 *
1069 * Returns the number of bytes that are actually in the stored address.
1070 */
1071 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1072 {
1073 size_t bytes;
1074 struct rpc_xprt *xprt;
1075
1076 rcu_read_lock();
1077 xprt = rcu_dereference(clnt->cl_xprt);
1078
1079 bytes = xprt->addrlen;
1080 if (bytes > bufsize)
1081 bytes = bufsize;
1082 memcpy(buf, &xprt->addr, bytes);
1083 rcu_read_unlock();
1084
1085 return bytes;
1086 }
1087 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1088
1089 /**
1090 * rpc_peeraddr2str - return remote peer address in printable format
1091 * @clnt: RPC client structure
1092 * @format: address format
1093 *
1094 * NB: the lifetime of the memory referenced by the returned pointer is
1095 * the same as the rpc_xprt itself. As long as the caller uses this
1096 * pointer, it must hold the RCU read lock.
1097 */
1098 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1099 enum rpc_display_format_t format)
1100 {
1101 struct rpc_xprt *xprt;
1102
1103 xprt = rcu_dereference(clnt->cl_xprt);
1104
1105 if (xprt->address_strings[format] != NULL)
1106 return xprt->address_strings[format];
1107 else
1108 return "unprintable";
1109 }
1110 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1111
1112 static const struct sockaddr_in rpc_inaddr_loopback = {
1113 .sin_family = AF_INET,
1114 .sin_addr.s_addr = htonl(INADDR_ANY),
1115 };
1116
1117 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1118 .sin6_family = AF_INET6,
1119 .sin6_addr = IN6ADDR_ANY_INIT,
1120 };
1121
1122 /*
1123 * Try a getsockname() on a connected datagram socket. Using a
1124 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1125 * This conserves the ephemeral port number space.
1126 *
1127 * Returns zero and fills in "buf" if successful; otherwise, a
1128 * negative errno is returned.
1129 */
1130 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1131 struct sockaddr *buf, int buflen)
1132 {
1133 struct socket *sock;
1134 int err;
1135
1136 err = __sock_create(net, sap->sa_family,
1137 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1138 if (err < 0) {
1139 dprintk("RPC: can't create UDP socket (%d)\n", err);
1140 goto out;
1141 }
1142
1143 switch (sap->sa_family) {
1144 case AF_INET:
1145 err = kernel_bind(sock,
1146 (struct sockaddr *)&rpc_inaddr_loopback,
1147 sizeof(rpc_inaddr_loopback));
1148 break;
1149 case AF_INET6:
1150 err = kernel_bind(sock,
1151 (struct sockaddr *)&rpc_in6addr_loopback,
1152 sizeof(rpc_in6addr_loopback));
1153 break;
1154 default:
1155 err = -EAFNOSUPPORT;
1156 goto out;
1157 }
1158 if (err < 0) {
1159 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1160 goto out_release;
1161 }
1162
1163 err = kernel_connect(sock, sap, salen, 0);
1164 if (err < 0) {
1165 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1166 goto out_release;
1167 }
1168
1169 err = kernel_getsockname(sock, buf, &buflen);
1170 if (err < 0) {
1171 dprintk("RPC: getsockname failed (%d)\n", err);
1172 goto out_release;
1173 }
1174
1175 err = 0;
1176 if (buf->sa_family == AF_INET6) {
1177 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1178 sin6->sin6_scope_id = 0;
1179 }
1180 dprintk("RPC: %s succeeded\n", __func__);
1181
1182 out_release:
1183 sock_release(sock);
1184 out:
1185 return err;
1186 }
1187
1188 /*
1189 * Scraping a connected socket failed, so we don't have a useable
1190 * local address. Fallback: generate an address that will prevent
1191 * the server from calling us back.
1192 *
1193 * Returns zero and fills in "buf" if successful; otherwise, a
1194 * negative errno is returned.
1195 */
1196 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1197 {
1198 switch (family) {
1199 case AF_INET:
1200 if (buflen < sizeof(rpc_inaddr_loopback))
1201 return -EINVAL;
1202 memcpy(buf, &rpc_inaddr_loopback,
1203 sizeof(rpc_inaddr_loopback));
1204 break;
1205 case AF_INET6:
1206 if (buflen < sizeof(rpc_in6addr_loopback))
1207 return -EINVAL;
1208 memcpy(buf, &rpc_in6addr_loopback,
1209 sizeof(rpc_in6addr_loopback));
1210 default:
1211 dprintk("RPC: %s: address family not supported\n",
1212 __func__);
1213 return -EAFNOSUPPORT;
1214 }
1215 dprintk("RPC: %s: succeeded\n", __func__);
1216 return 0;
1217 }
1218
1219 /**
1220 * rpc_localaddr - discover local endpoint address for an RPC client
1221 * @clnt: RPC client structure
1222 * @buf: target buffer
1223 * @buflen: size of target buffer, in bytes
1224 *
1225 * Returns zero and fills in "buf" and "buflen" if successful;
1226 * otherwise, a negative errno is returned.
1227 *
1228 * This works even if the underlying transport is not currently connected,
1229 * or if the upper layer never previously provided a source address.
1230 *
1231 * The result of this function call is transient: multiple calls in
1232 * succession may give different results, depending on how local
1233 * networking configuration changes over time.
1234 */
1235 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1236 {
1237 struct sockaddr_storage address;
1238 struct sockaddr *sap = (struct sockaddr *)&address;
1239 struct rpc_xprt *xprt;
1240 struct net *net;
1241 size_t salen;
1242 int err;
1243
1244 rcu_read_lock();
1245 xprt = rcu_dereference(clnt->cl_xprt);
1246 salen = xprt->addrlen;
1247 memcpy(sap, &xprt->addr, salen);
1248 net = get_net(xprt->xprt_net);
1249 rcu_read_unlock();
1250
1251 rpc_set_port(sap, 0);
1252 err = rpc_sockname(net, sap, salen, buf, buflen);
1253 put_net(net);
1254 if (err != 0)
1255 /* Couldn't discover local address, return ANYADDR */
1256 return rpc_anyaddr(sap->sa_family, buf, buflen);
1257 return 0;
1258 }
1259 EXPORT_SYMBOL_GPL(rpc_localaddr);
1260
1261 void
1262 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1263 {
1264 struct rpc_xprt *xprt;
1265
1266 rcu_read_lock();
1267 xprt = rcu_dereference(clnt->cl_xprt);
1268 if (xprt->ops->set_buffer_size)
1269 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1270 rcu_read_unlock();
1271 }
1272 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1273
1274 /**
1275 * rpc_protocol - Get transport protocol number for an RPC client
1276 * @clnt: RPC client to query
1277 *
1278 */
1279 int rpc_protocol(struct rpc_clnt *clnt)
1280 {
1281 int protocol;
1282
1283 rcu_read_lock();
1284 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1285 rcu_read_unlock();
1286 return protocol;
1287 }
1288 EXPORT_SYMBOL_GPL(rpc_protocol);
1289
1290 /**
1291 * rpc_net_ns - Get the network namespace for this RPC client
1292 * @clnt: RPC client to query
1293 *
1294 */
1295 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1296 {
1297 struct net *ret;
1298
1299 rcu_read_lock();
1300 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1301 rcu_read_unlock();
1302 return ret;
1303 }
1304 EXPORT_SYMBOL_GPL(rpc_net_ns);
1305
1306 /**
1307 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1308 * @clnt: RPC client to query
1309 *
1310 * For stream transports, this is one RPC record fragment (see RFC
1311 * 1831), as we don't support multi-record requests yet. For datagram
1312 * transports, this is the size of an IP packet minus the IP, UDP, and
1313 * RPC header sizes.
1314 */
1315 size_t rpc_max_payload(struct rpc_clnt *clnt)
1316 {
1317 size_t ret;
1318
1319 rcu_read_lock();
1320 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1321 rcu_read_unlock();
1322 return ret;
1323 }
1324 EXPORT_SYMBOL_GPL(rpc_max_payload);
1325
1326 /**
1327 * rpc_get_timeout - Get timeout for transport in units of HZ
1328 * @clnt: RPC client to query
1329 */
1330 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1331 {
1332 unsigned long ret;
1333
1334 rcu_read_lock();
1335 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1336 rcu_read_unlock();
1337 return ret;
1338 }
1339 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1340
1341 /**
1342 * rpc_force_rebind - force transport to check that remote port is unchanged
1343 * @clnt: client to rebind
1344 *
1345 */
1346 void rpc_force_rebind(struct rpc_clnt *clnt)
1347 {
1348 if (clnt->cl_autobind) {
1349 rcu_read_lock();
1350 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1351 rcu_read_unlock();
1352 }
1353 }
1354 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1355
1356 /*
1357 * Restart an (async) RPC call from the call_prepare state.
1358 * Usually called from within the exit handler.
1359 */
1360 int
1361 rpc_restart_call_prepare(struct rpc_task *task)
1362 {
1363 if (RPC_ASSASSINATED(task))
1364 return 0;
1365 task->tk_action = call_start;
1366 if (task->tk_ops->rpc_call_prepare != NULL)
1367 task->tk_action = rpc_prepare_task;
1368 return 1;
1369 }
1370 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1371
1372 /*
1373 * Restart an (async) RPC call. Usually called from within the
1374 * exit handler.
1375 */
1376 int
1377 rpc_restart_call(struct rpc_task *task)
1378 {
1379 if (RPC_ASSASSINATED(task))
1380 return 0;
1381 task->tk_action = call_start;
1382 return 1;
1383 }
1384 EXPORT_SYMBOL_GPL(rpc_restart_call);
1385
1386 #ifdef RPC_DEBUG
1387 static const char *rpc_proc_name(const struct rpc_task *task)
1388 {
1389 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1390
1391 if (proc) {
1392 if (proc->p_name)
1393 return proc->p_name;
1394 else
1395 return "NULL";
1396 } else
1397 return "no proc";
1398 }
1399 #endif
1400
1401 /*
1402 * 0. Initial state
1403 *
1404 * Other FSM states can be visited zero or more times, but
1405 * this state is visited exactly once for each RPC.
1406 */
1407 static void
1408 call_start(struct rpc_task *task)
1409 {
1410 struct rpc_clnt *clnt = task->tk_client;
1411
1412 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1413 clnt->cl_program->name, clnt->cl_vers,
1414 rpc_proc_name(task),
1415 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1416
1417 /* Increment call count */
1418 task->tk_msg.rpc_proc->p_count++;
1419 clnt->cl_stats->rpccnt++;
1420 task->tk_action = call_reserve;
1421 }
1422
1423 /*
1424 * 1. Reserve an RPC call slot
1425 */
1426 static void
1427 call_reserve(struct rpc_task *task)
1428 {
1429 dprint_status(task);
1430
1431 task->tk_status = 0;
1432 task->tk_action = call_reserveresult;
1433 xprt_reserve(task);
1434 }
1435
1436 static void call_retry_reserve(struct rpc_task *task);
1437
1438 /*
1439 * 1b. Grok the result of xprt_reserve()
1440 */
1441 static void
1442 call_reserveresult(struct rpc_task *task)
1443 {
1444 int status = task->tk_status;
1445
1446 dprint_status(task);
1447
1448 /*
1449 * After a call to xprt_reserve(), we must have either
1450 * a request slot or else an error status.
1451 */
1452 task->tk_status = 0;
1453 if (status >= 0) {
1454 if (task->tk_rqstp) {
1455 task->tk_action = call_refresh;
1456 return;
1457 }
1458
1459 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1460 __func__, status);
1461 rpc_exit(task, -EIO);
1462 return;
1463 }
1464
1465 /*
1466 * Even though there was an error, we may have acquired
1467 * a request slot somehow. Make sure not to leak it.
1468 */
1469 if (task->tk_rqstp) {
1470 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1471 __func__, status);
1472 xprt_release(task);
1473 }
1474
1475 switch (status) {
1476 case -ENOMEM:
1477 rpc_delay(task, HZ >> 2);
1478 case -EAGAIN: /* woken up; retry */
1479 task->tk_action = call_retry_reserve;
1480 return;
1481 case -EIO: /* probably a shutdown */
1482 break;
1483 default:
1484 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1485 __func__, status);
1486 break;
1487 }
1488 rpc_exit(task, status);
1489 }
1490
1491 /*
1492 * 1c. Retry reserving an RPC call slot
1493 */
1494 static void
1495 call_retry_reserve(struct rpc_task *task)
1496 {
1497 dprint_status(task);
1498
1499 task->tk_status = 0;
1500 task->tk_action = call_reserveresult;
1501 xprt_retry_reserve(task);
1502 }
1503
1504 /*
1505 * 2. Bind and/or refresh the credentials
1506 */
1507 static void
1508 call_refresh(struct rpc_task *task)
1509 {
1510 dprint_status(task);
1511
1512 task->tk_action = call_refreshresult;
1513 task->tk_status = 0;
1514 task->tk_client->cl_stats->rpcauthrefresh++;
1515 rpcauth_refreshcred(task);
1516 }
1517
1518 /*
1519 * 2a. Process the results of a credential refresh
1520 */
1521 static void
1522 call_refreshresult(struct rpc_task *task)
1523 {
1524 int status = task->tk_status;
1525
1526 dprint_status(task);
1527
1528 task->tk_status = 0;
1529 task->tk_action = call_refresh;
1530 switch (status) {
1531 case 0:
1532 if (rpcauth_uptodatecred(task)) {
1533 task->tk_action = call_allocate;
1534 return;
1535 }
1536 /* Use rate-limiting and a max number of retries if refresh
1537 * had status 0 but failed to update the cred.
1538 */
1539 case -ETIMEDOUT:
1540 rpc_delay(task, 3*HZ);
1541 case -EAGAIN:
1542 status = -EACCES;
1543 case -EKEYEXPIRED:
1544 if (!task->tk_cred_retry)
1545 break;
1546 task->tk_cred_retry--;
1547 dprintk("RPC: %5u %s: retry refresh creds\n",
1548 task->tk_pid, __func__);
1549 return;
1550 }
1551 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1552 task->tk_pid, __func__, status);
1553 rpc_exit(task, status);
1554 }
1555
1556 /*
1557 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1558 * (Note: buffer memory is freed in xprt_release).
1559 */
1560 static void
1561 call_allocate(struct rpc_task *task)
1562 {
1563 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1564 struct rpc_rqst *req = task->tk_rqstp;
1565 struct rpc_xprt *xprt = req->rq_xprt;
1566 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1567
1568 dprint_status(task);
1569
1570 task->tk_status = 0;
1571 task->tk_action = call_bind;
1572
1573 if (req->rq_buffer)
1574 return;
1575
1576 if (proc->p_proc != 0) {
1577 BUG_ON(proc->p_arglen == 0);
1578 if (proc->p_decode != NULL)
1579 BUG_ON(proc->p_replen == 0);
1580 }
1581
1582 /*
1583 * Calculate the size (in quads) of the RPC call
1584 * and reply headers, and convert both values
1585 * to byte sizes.
1586 */
1587 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1588 req->rq_callsize <<= 2;
1589 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1590 req->rq_rcvsize <<= 2;
1591
1592 req->rq_buffer = xprt->ops->buf_alloc(task,
1593 req->rq_callsize + req->rq_rcvsize);
1594 if (req->rq_buffer != NULL)
1595 return;
1596
1597 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1598
1599 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1600 task->tk_action = call_allocate;
1601 rpc_delay(task, HZ>>4);
1602 return;
1603 }
1604
1605 rpc_exit(task, -ERESTARTSYS);
1606 }
1607
1608 static inline int
1609 rpc_task_need_encode(struct rpc_task *task)
1610 {
1611 return task->tk_rqstp->rq_snd_buf.len == 0;
1612 }
1613
1614 static inline void
1615 rpc_task_force_reencode(struct rpc_task *task)
1616 {
1617 task->tk_rqstp->rq_snd_buf.len = 0;
1618 task->tk_rqstp->rq_bytes_sent = 0;
1619 }
1620
1621 static inline void
1622 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1623 {
1624 buf->head[0].iov_base = start;
1625 buf->head[0].iov_len = len;
1626 buf->tail[0].iov_len = 0;
1627 buf->page_len = 0;
1628 buf->flags = 0;
1629 buf->len = 0;
1630 buf->buflen = len;
1631 }
1632
1633 /*
1634 * 3. Encode arguments of an RPC call
1635 */
1636 static void
1637 rpc_xdr_encode(struct rpc_task *task)
1638 {
1639 struct rpc_rqst *req = task->tk_rqstp;
1640 kxdreproc_t encode;
1641 __be32 *p;
1642
1643 dprint_status(task);
1644
1645 rpc_xdr_buf_init(&req->rq_snd_buf,
1646 req->rq_buffer,
1647 req->rq_callsize);
1648 rpc_xdr_buf_init(&req->rq_rcv_buf,
1649 (char *)req->rq_buffer + req->rq_callsize,
1650 req->rq_rcvsize);
1651
1652 p = rpc_encode_header(task);
1653 if (p == NULL) {
1654 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1655 rpc_exit(task, -EIO);
1656 return;
1657 }
1658
1659 encode = task->tk_msg.rpc_proc->p_encode;
1660 if (encode == NULL)
1661 return;
1662
1663 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1664 task->tk_msg.rpc_argp);
1665 }
1666
1667 /*
1668 * 4. Get the server port number if not yet set
1669 */
1670 static void
1671 call_bind(struct rpc_task *task)
1672 {
1673 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1674
1675 dprint_status(task);
1676
1677 task->tk_action = call_connect;
1678 if (!xprt_bound(xprt)) {
1679 task->tk_action = call_bind_status;
1680 task->tk_timeout = xprt->bind_timeout;
1681 xprt->ops->rpcbind(task);
1682 }
1683 }
1684
1685 /*
1686 * 4a. Sort out bind result
1687 */
1688 static void
1689 call_bind_status(struct rpc_task *task)
1690 {
1691 int status = -EIO;
1692
1693 if (task->tk_status >= 0) {
1694 dprint_status(task);
1695 task->tk_status = 0;
1696 task->tk_action = call_connect;
1697 return;
1698 }
1699
1700 trace_rpc_bind_status(task);
1701 switch (task->tk_status) {
1702 case -ENOMEM:
1703 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1704 rpc_delay(task, HZ >> 2);
1705 goto retry_timeout;
1706 case -EACCES:
1707 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1708 "unavailable\n", task->tk_pid);
1709 /* fail immediately if this is an RPC ping */
1710 if (task->tk_msg.rpc_proc->p_proc == 0) {
1711 status = -EOPNOTSUPP;
1712 break;
1713 }
1714 if (task->tk_rebind_retry == 0)
1715 break;
1716 task->tk_rebind_retry--;
1717 rpc_delay(task, 3*HZ);
1718 goto retry_timeout;
1719 case -ETIMEDOUT:
1720 dprintk("RPC: %5u rpcbind request timed out\n",
1721 task->tk_pid);
1722 goto retry_timeout;
1723 case -EPFNOSUPPORT:
1724 /* server doesn't support any rpcbind version we know of */
1725 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1726 task->tk_pid);
1727 break;
1728 case -EPROTONOSUPPORT:
1729 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1730 task->tk_pid);
1731 task->tk_status = 0;
1732 task->tk_action = call_bind;
1733 return;
1734 case -ECONNREFUSED: /* connection problems */
1735 case -ECONNRESET:
1736 case -ECONNABORTED:
1737 case -ENOTCONN:
1738 case -EHOSTDOWN:
1739 case -EHOSTUNREACH:
1740 case -ENETUNREACH:
1741 case -EPIPE:
1742 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1743 task->tk_pid, task->tk_status);
1744 if (!RPC_IS_SOFTCONN(task)) {
1745 rpc_delay(task, 5*HZ);
1746 goto retry_timeout;
1747 }
1748 status = task->tk_status;
1749 break;
1750 default:
1751 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1752 task->tk_pid, -task->tk_status);
1753 }
1754
1755 rpc_exit(task, status);
1756 return;
1757
1758 retry_timeout:
1759 task->tk_action = call_timeout;
1760 }
1761
1762 /*
1763 * 4b. Connect to the RPC server
1764 */
1765 static void
1766 call_connect(struct rpc_task *task)
1767 {
1768 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1769
1770 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1771 task->tk_pid, xprt,
1772 (xprt_connected(xprt) ? "is" : "is not"));
1773
1774 task->tk_action = call_transmit;
1775 if (!xprt_connected(xprt)) {
1776 task->tk_action = call_connect_status;
1777 if (task->tk_status < 0)
1778 return;
1779 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1780 rpc_exit(task, -ENOTCONN);
1781 return;
1782 }
1783 xprt_connect(task);
1784 }
1785 }
1786
1787 /*
1788 * 4c. Sort out connect result
1789 */
1790 static void
1791 call_connect_status(struct rpc_task *task)
1792 {
1793 struct rpc_clnt *clnt = task->tk_client;
1794 int status = task->tk_status;
1795
1796 dprint_status(task);
1797
1798 trace_rpc_connect_status(task, status);
1799 task->tk_status = 0;
1800 switch (status) {
1801 /* if soft mounted, test if we've timed out */
1802 case -ETIMEDOUT:
1803 task->tk_action = call_timeout;
1804 return;
1805 case -ECONNREFUSED:
1806 case -ECONNRESET:
1807 case -ECONNABORTED:
1808 case -ENETUNREACH:
1809 case -EHOSTUNREACH:
1810 /* retry with existing socket, after a delay */
1811 rpc_delay(task, 3*HZ);
1812 if (RPC_IS_SOFTCONN(task))
1813 break;
1814 case -EAGAIN:
1815 task->tk_action = call_bind;
1816 return;
1817 case 0:
1818 clnt->cl_stats->netreconn++;
1819 task->tk_action = call_transmit;
1820 return;
1821 }
1822 rpc_exit(task, status);
1823 }
1824
1825 /*
1826 * 5. Transmit the RPC request, and wait for reply
1827 */
1828 static void
1829 call_transmit(struct rpc_task *task)
1830 {
1831 int is_retrans = RPC_WAS_SENT(task);
1832
1833 dprint_status(task);
1834
1835 task->tk_action = call_status;
1836 if (task->tk_status < 0)
1837 return;
1838 if (!xprt_prepare_transmit(task))
1839 return;
1840 task->tk_action = call_transmit_status;
1841 /* Encode here so that rpcsec_gss can use correct sequence number. */
1842 if (rpc_task_need_encode(task)) {
1843 rpc_xdr_encode(task);
1844 /* Did the encode result in an error condition? */
1845 if (task->tk_status != 0) {
1846 /* Was the error nonfatal? */
1847 if (task->tk_status == -EAGAIN)
1848 rpc_delay(task, HZ >> 4);
1849 else
1850 rpc_exit(task, task->tk_status);
1851 return;
1852 }
1853 }
1854 xprt_transmit(task);
1855 if (task->tk_status < 0)
1856 return;
1857 if (is_retrans)
1858 task->tk_client->cl_stats->rpcretrans++;
1859 /*
1860 * On success, ensure that we call xprt_end_transmit() before sleeping
1861 * in order to allow access to the socket to other RPC requests.
1862 */
1863 call_transmit_status(task);
1864 if (rpc_reply_expected(task))
1865 return;
1866 task->tk_action = rpc_exit_task;
1867 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1868 }
1869
1870 /*
1871 * 5a. Handle cleanup after a transmission
1872 */
1873 static void
1874 call_transmit_status(struct rpc_task *task)
1875 {
1876 task->tk_action = call_status;
1877
1878 /*
1879 * Common case: success. Force the compiler to put this
1880 * test first.
1881 */
1882 if (task->tk_status == 0) {
1883 xprt_end_transmit(task);
1884 rpc_task_force_reencode(task);
1885 return;
1886 }
1887
1888 switch (task->tk_status) {
1889 case -EAGAIN:
1890 break;
1891 default:
1892 dprint_status(task);
1893 xprt_end_transmit(task);
1894 rpc_task_force_reencode(task);
1895 break;
1896 /*
1897 * Special cases: if we've been waiting on the
1898 * socket's write_space() callback, or if the
1899 * socket just returned a connection error,
1900 * then hold onto the transport lock.
1901 */
1902 case -ECONNREFUSED:
1903 case -EHOSTDOWN:
1904 case -EHOSTUNREACH:
1905 case -ENETUNREACH:
1906 if (RPC_IS_SOFTCONN(task)) {
1907 xprt_end_transmit(task);
1908 rpc_exit(task, task->tk_status);
1909 break;
1910 }
1911 case -ECONNRESET:
1912 case -ECONNABORTED:
1913 case -ENOTCONN:
1914 case -EPIPE:
1915 rpc_task_force_reencode(task);
1916 }
1917 }
1918
1919 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1920 /*
1921 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1922 * addition, disconnect on connectivity errors.
1923 */
1924 static void
1925 call_bc_transmit(struct rpc_task *task)
1926 {
1927 struct rpc_rqst *req = task->tk_rqstp;
1928
1929 if (!xprt_prepare_transmit(task)) {
1930 /*
1931 * Could not reserve the transport. Try again after the
1932 * transport is released.
1933 */
1934 task->tk_status = 0;
1935 task->tk_action = call_bc_transmit;
1936 return;
1937 }
1938
1939 task->tk_action = rpc_exit_task;
1940 if (task->tk_status < 0) {
1941 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1942 "error: %d\n", task->tk_status);
1943 return;
1944 }
1945
1946 xprt_transmit(task);
1947 xprt_end_transmit(task);
1948 dprint_status(task);
1949 switch (task->tk_status) {
1950 case 0:
1951 /* Success */
1952 break;
1953 case -EHOSTDOWN:
1954 case -EHOSTUNREACH:
1955 case -ENETUNREACH:
1956 case -ETIMEDOUT:
1957 /*
1958 * Problem reaching the server. Disconnect and let the
1959 * forechannel reestablish the connection. The server will
1960 * have to retransmit the backchannel request and we'll
1961 * reprocess it. Since these ops are idempotent, there's no
1962 * need to cache our reply at this time.
1963 */
1964 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1965 "error: %d\n", task->tk_status);
1966 xprt_conditional_disconnect(req->rq_xprt,
1967 req->rq_connect_cookie);
1968 break;
1969 default:
1970 /*
1971 * We were unable to reply and will have to drop the
1972 * request. The server should reconnect and retransmit.
1973 */
1974 WARN_ON_ONCE(task->tk_status == -EAGAIN);
1975 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1976 "error: %d\n", task->tk_status);
1977 break;
1978 }
1979 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1980 }
1981 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1982
1983 /*
1984 * 6. Sort out the RPC call status
1985 */
1986 static void
1987 call_status(struct rpc_task *task)
1988 {
1989 struct rpc_clnt *clnt = task->tk_client;
1990 struct rpc_rqst *req = task->tk_rqstp;
1991 int status;
1992
1993 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1994 task->tk_status = req->rq_reply_bytes_recvd;
1995
1996 dprint_status(task);
1997
1998 status = task->tk_status;
1999 if (status >= 0) {
2000 task->tk_action = call_decode;
2001 return;
2002 }
2003
2004 trace_rpc_call_status(task);
2005 task->tk_status = 0;
2006 switch(status) {
2007 case -EHOSTDOWN:
2008 case -EHOSTUNREACH:
2009 case -ENETUNREACH:
2010 /*
2011 * Delay any retries for 3 seconds, then handle as if it
2012 * were a timeout.
2013 */
2014 rpc_delay(task, 3*HZ);
2015 case -ETIMEDOUT:
2016 task->tk_action = call_timeout;
2017 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2018 && task->tk_client->cl_discrtry)
2019 xprt_conditional_disconnect(req->rq_xprt,
2020 req->rq_connect_cookie);
2021 break;
2022 case -ECONNREFUSED:
2023 case -ECONNRESET:
2024 case -ECONNABORTED:
2025 rpc_force_rebind(clnt);
2026 rpc_delay(task, 3*HZ);
2027 case -EPIPE:
2028 case -ENOTCONN:
2029 task->tk_action = call_bind;
2030 break;
2031 case -EAGAIN:
2032 task->tk_action = call_transmit;
2033 break;
2034 case -EIO:
2035 /* shutdown or soft timeout */
2036 rpc_exit(task, status);
2037 break;
2038 default:
2039 if (clnt->cl_chatty)
2040 printk("%s: RPC call returned error %d\n",
2041 clnt->cl_program->name, -status);
2042 rpc_exit(task, status);
2043 }
2044 }
2045
2046 /*
2047 * 6a. Handle RPC timeout
2048 * We do not release the request slot, so we keep using the
2049 * same XID for all retransmits.
2050 */
2051 static void
2052 call_timeout(struct rpc_task *task)
2053 {
2054 struct rpc_clnt *clnt = task->tk_client;
2055
2056 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2057 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2058 goto retry;
2059 }
2060
2061 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2062 task->tk_timeouts++;
2063
2064 if (RPC_IS_SOFTCONN(task)) {
2065 rpc_exit(task, -ETIMEDOUT);
2066 return;
2067 }
2068 if (RPC_IS_SOFT(task)) {
2069 if (clnt->cl_chatty) {
2070 rcu_read_lock();
2071 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2072 clnt->cl_program->name,
2073 rcu_dereference(clnt->cl_xprt)->servername);
2074 rcu_read_unlock();
2075 }
2076 if (task->tk_flags & RPC_TASK_TIMEOUT)
2077 rpc_exit(task, -ETIMEDOUT);
2078 else
2079 rpc_exit(task, -EIO);
2080 return;
2081 }
2082
2083 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2084 task->tk_flags |= RPC_CALL_MAJORSEEN;
2085 if (clnt->cl_chatty) {
2086 rcu_read_lock();
2087 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2088 clnt->cl_program->name,
2089 rcu_dereference(clnt->cl_xprt)->servername);
2090 rcu_read_unlock();
2091 }
2092 }
2093 rpc_force_rebind(clnt);
2094 /*
2095 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2096 * event? RFC2203 requires the server to drop all such requests.
2097 */
2098 rpcauth_invalcred(task);
2099
2100 retry:
2101 task->tk_action = call_bind;
2102 task->tk_status = 0;
2103 }
2104
2105 /*
2106 * 7. Decode the RPC reply
2107 */
2108 static void
2109 call_decode(struct rpc_task *task)
2110 {
2111 struct rpc_clnt *clnt = task->tk_client;
2112 struct rpc_rqst *req = task->tk_rqstp;
2113 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2114 __be32 *p;
2115
2116 dprint_status(task);
2117
2118 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2119 if (clnt->cl_chatty) {
2120 rcu_read_lock();
2121 printk(KERN_NOTICE "%s: server %s OK\n",
2122 clnt->cl_program->name,
2123 rcu_dereference(clnt->cl_xprt)->servername);
2124 rcu_read_unlock();
2125 }
2126 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2127 }
2128
2129 /*
2130 * Ensure that we see all writes made by xprt_complete_rqst()
2131 * before it changed req->rq_reply_bytes_recvd.
2132 */
2133 smp_rmb();
2134 req->rq_rcv_buf.len = req->rq_private_buf.len;
2135
2136 /* Check that the softirq receive buffer is valid */
2137 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2138 sizeof(req->rq_rcv_buf)) != 0);
2139
2140 if (req->rq_rcv_buf.len < 12) {
2141 if (!RPC_IS_SOFT(task)) {
2142 task->tk_action = call_bind;
2143 goto out_retry;
2144 }
2145 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2146 clnt->cl_program->name, task->tk_status);
2147 task->tk_action = call_timeout;
2148 goto out_retry;
2149 }
2150
2151 p = rpc_verify_header(task);
2152 if (IS_ERR(p)) {
2153 if (p == ERR_PTR(-EAGAIN))
2154 goto out_retry;
2155 return;
2156 }
2157
2158 task->tk_action = rpc_exit_task;
2159
2160 if (decode) {
2161 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2162 task->tk_msg.rpc_resp);
2163 }
2164 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2165 task->tk_status);
2166 return;
2167 out_retry:
2168 task->tk_status = 0;
2169 /* Note: rpc_verify_header() may have freed the RPC slot */
2170 if (task->tk_rqstp == req) {
2171 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2172 if (task->tk_client->cl_discrtry)
2173 xprt_conditional_disconnect(req->rq_xprt,
2174 req->rq_connect_cookie);
2175 }
2176 }
2177
2178 static __be32 *
2179 rpc_encode_header(struct rpc_task *task)
2180 {
2181 struct rpc_clnt *clnt = task->tk_client;
2182 struct rpc_rqst *req = task->tk_rqstp;
2183 __be32 *p = req->rq_svec[0].iov_base;
2184
2185 /* FIXME: check buffer size? */
2186
2187 p = xprt_skip_transport_header(req->rq_xprt, p);
2188 *p++ = req->rq_xid; /* XID */
2189 *p++ = htonl(RPC_CALL); /* CALL */
2190 *p++ = htonl(RPC_VERSION); /* RPC version */
2191 *p++ = htonl(clnt->cl_prog); /* program number */
2192 *p++ = htonl(clnt->cl_vers); /* program version */
2193 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2194 p = rpcauth_marshcred(task, p);
2195 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2196 return p;
2197 }
2198
2199 static __be32 *
2200 rpc_verify_header(struct rpc_task *task)
2201 {
2202 struct rpc_clnt *clnt = task->tk_client;
2203 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2204 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2205 __be32 *p = iov->iov_base;
2206 u32 n;
2207 int error = -EACCES;
2208
2209 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2210 /* RFC-1014 says that the representation of XDR data must be a
2211 * multiple of four bytes
2212 * - if it isn't pointer subtraction in the NFS client may give
2213 * undefined results
2214 */
2215 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2216 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2217 task->tk_rqstp->rq_rcv_buf.len);
2218 error = -EIO;
2219 goto out_err;
2220 }
2221 if ((len -= 3) < 0)
2222 goto out_overflow;
2223
2224 p += 1; /* skip XID */
2225 if ((n = ntohl(*p++)) != RPC_REPLY) {
2226 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2227 task->tk_pid, __func__, n);
2228 error = -EIO;
2229 goto out_garbage;
2230 }
2231
2232 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2233 if (--len < 0)
2234 goto out_overflow;
2235 switch ((n = ntohl(*p++))) {
2236 case RPC_AUTH_ERROR:
2237 break;
2238 case RPC_MISMATCH:
2239 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2240 task->tk_pid, __func__);
2241 error = -EPROTONOSUPPORT;
2242 goto out_err;
2243 default:
2244 dprintk("RPC: %5u %s: RPC call rejected, "
2245 "unknown error: %x\n",
2246 task->tk_pid, __func__, n);
2247 error = -EIO;
2248 goto out_err;
2249 }
2250 if (--len < 0)
2251 goto out_overflow;
2252 switch ((n = ntohl(*p++))) {
2253 case RPC_AUTH_REJECTEDCRED:
2254 case RPC_AUTH_REJECTEDVERF:
2255 case RPCSEC_GSS_CREDPROBLEM:
2256 case RPCSEC_GSS_CTXPROBLEM:
2257 if (!task->tk_cred_retry)
2258 break;
2259 task->tk_cred_retry--;
2260 dprintk("RPC: %5u %s: retry stale creds\n",
2261 task->tk_pid, __func__);
2262 rpcauth_invalcred(task);
2263 /* Ensure we obtain a new XID! */
2264 xprt_release(task);
2265 task->tk_action = call_reserve;
2266 goto out_retry;
2267 case RPC_AUTH_BADCRED:
2268 case RPC_AUTH_BADVERF:
2269 /* possibly garbled cred/verf? */
2270 if (!task->tk_garb_retry)
2271 break;
2272 task->tk_garb_retry--;
2273 dprintk("RPC: %5u %s: retry garbled creds\n",
2274 task->tk_pid, __func__);
2275 task->tk_action = call_bind;
2276 goto out_retry;
2277 case RPC_AUTH_TOOWEAK:
2278 rcu_read_lock();
2279 printk(KERN_NOTICE "RPC: server %s requires stronger "
2280 "authentication.\n",
2281 rcu_dereference(clnt->cl_xprt)->servername);
2282 rcu_read_unlock();
2283 break;
2284 default:
2285 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2286 task->tk_pid, __func__, n);
2287 error = -EIO;
2288 }
2289 dprintk("RPC: %5u %s: call rejected %d\n",
2290 task->tk_pid, __func__, n);
2291 goto out_err;
2292 }
2293 p = rpcauth_checkverf(task, p);
2294 if (IS_ERR(p)) {
2295 error = PTR_ERR(p);
2296 dprintk("RPC: %5u %s: auth check failed with %d\n",
2297 task->tk_pid, __func__, error);
2298 goto out_garbage; /* bad verifier, retry */
2299 }
2300 len = p - (__be32 *)iov->iov_base - 1;
2301 if (len < 0)
2302 goto out_overflow;
2303 switch ((n = ntohl(*p++))) {
2304 case RPC_SUCCESS:
2305 return p;
2306 case RPC_PROG_UNAVAIL:
2307 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2308 "by server %s\n", task->tk_pid, __func__,
2309 (unsigned int)clnt->cl_prog,
2310 rcu_dereference(clnt->cl_xprt)->servername);
2311 error = -EPFNOSUPPORT;
2312 goto out_err;
2313 case RPC_PROG_MISMATCH:
2314 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2315 "by server %s\n", task->tk_pid, __func__,
2316 (unsigned int)clnt->cl_prog,
2317 (unsigned int)clnt->cl_vers,
2318 rcu_dereference(clnt->cl_xprt)->servername);
2319 error = -EPROTONOSUPPORT;
2320 goto out_err;
2321 case RPC_PROC_UNAVAIL:
2322 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2323 "version %u on server %s\n",
2324 task->tk_pid, __func__,
2325 rpc_proc_name(task),
2326 clnt->cl_prog, clnt->cl_vers,
2327 rcu_dereference(clnt->cl_xprt)->servername);
2328 error = -EOPNOTSUPP;
2329 goto out_err;
2330 case RPC_GARBAGE_ARGS:
2331 dprintk("RPC: %5u %s: server saw garbage\n",
2332 task->tk_pid, __func__);
2333 break; /* retry */
2334 default:
2335 dprintk("RPC: %5u %s: server accept status: %x\n",
2336 task->tk_pid, __func__, n);
2337 /* Also retry */
2338 }
2339
2340 out_garbage:
2341 clnt->cl_stats->rpcgarbage++;
2342 if (task->tk_garb_retry) {
2343 task->tk_garb_retry--;
2344 dprintk("RPC: %5u %s: retrying\n",
2345 task->tk_pid, __func__);
2346 task->tk_action = call_bind;
2347 out_retry:
2348 return ERR_PTR(-EAGAIN);
2349 }
2350 out_err:
2351 rpc_exit(task, error);
2352 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2353 __func__, error);
2354 return ERR_PTR(error);
2355 out_overflow:
2356 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2357 __func__);
2358 goto out_garbage;
2359 }
2360
2361 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2362 {
2363 }
2364
2365 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2366 {
2367 return 0;
2368 }
2369
2370 static struct rpc_procinfo rpcproc_null = {
2371 .p_encode = rpcproc_encode_null,
2372 .p_decode = rpcproc_decode_null,
2373 };
2374
2375 static int rpc_ping(struct rpc_clnt *clnt)
2376 {
2377 struct rpc_message msg = {
2378 .rpc_proc = &rpcproc_null,
2379 };
2380 int err;
2381 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2382 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2383 put_rpccred(msg.rpc_cred);
2384 return err;
2385 }
2386
2387 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2388 {
2389 struct rpc_message msg = {
2390 .rpc_proc = &rpcproc_null,
2391 .rpc_cred = cred,
2392 };
2393 struct rpc_task_setup task_setup_data = {
2394 .rpc_client = clnt,
2395 .rpc_message = &msg,
2396 .callback_ops = &rpc_default_ops,
2397 .flags = flags,
2398 };
2399 return rpc_run_task(&task_setup_data);
2400 }
2401 EXPORT_SYMBOL_GPL(rpc_call_null);
2402
2403 #ifdef RPC_DEBUG
2404 static void rpc_show_header(void)
2405 {
2406 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2407 "-timeout ---ops--\n");
2408 }
2409
2410 static void rpc_show_task(const struct rpc_clnt *clnt,
2411 const struct rpc_task *task)
2412 {
2413 const char *rpc_waitq = "none";
2414
2415 if (RPC_IS_QUEUED(task))
2416 rpc_waitq = rpc_qname(task->tk_waitqueue);
2417
2418 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2419 task->tk_pid, task->tk_flags, task->tk_status,
2420 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2421 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2422 task->tk_action, rpc_waitq);
2423 }
2424
2425 void rpc_show_tasks(struct net *net)
2426 {
2427 struct rpc_clnt *clnt;
2428 struct rpc_task *task;
2429 int header = 0;
2430 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2431
2432 spin_lock(&sn->rpc_client_lock);
2433 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2434 spin_lock(&clnt->cl_lock);
2435 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2436 if (!header) {
2437 rpc_show_header();
2438 header++;
2439 }
2440 rpc_show_task(clnt, task);
2441 }
2442 spin_unlock(&clnt->cl_lock);
2443 }
2444 spin_unlock(&sn->rpc_client_lock);
2445 }
2446 #endif
Linux with added FPC-III support