?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge tag 'locks-v3.16-2' of git://git.samba.org/jlayton/linux
[linux/fpc-iii.git] / net / sunrpc / clnt.c
blob2e6ab10734f6869af45a422bad6253e9de5cd580
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 struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
442 struct rpc_xprt *xprt)
443 {
444 struct rpc_clnt *clnt = NULL;
445
446 clnt = rpc_new_client(args, xprt, NULL);
447 if (IS_ERR(clnt))
448 return clnt;
449
450 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
451 int err = rpc_ping(clnt);
452 if (err != 0) {
453 rpc_shutdown_client(clnt);
454 return ERR_PTR(err);
455 }
456 }
457
458 clnt->cl_softrtry = 1;
459 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
460 clnt->cl_softrtry = 0;
461
462 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
463 clnt->cl_autobind = 1;
464 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
465 clnt->cl_discrtry = 1;
466 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
467 clnt->cl_chatty = 1;
468
469 return clnt;
470 }
471 EXPORT_SYMBOL_GPL(rpc_create_xprt);
472
473 /**
474 * rpc_create - create an RPC client and transport with one call
475 * @args: rpc_clnt create argument structure
476 *
477 * Creates and initializes an RPC transport and an RPC client.
478 *
479 * It can ping the server in order to determine if it is up, and to see if
480 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
481 * this behavior so asynchronous tasks can also use rpc_create.
482 */
483 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
484 {
485 struct rpc_xprt *xprt;
486 struct xprt_create xprtargs = {
487 .net = args->net,
488 .ident = args->protocol,
489 .srcaddr = args->saddress,
490 .dstaddr = args->address,
491 .addrlen = args->addrsize,
492 .servername = args->servername,
493 .bc_xprt = args->bc_xprt,
494 };
495 char servername[48];
496
497 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
498 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
499 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
500 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
501 /*
502 * If the caller chooses not to specify a hostname, whip
503 * up a string representation of the passed-in address.
504 */
505 if (xprtargs.servername == NULL) {
506 struct sockaddr_un *sun =
507 (struct sockaddr_un *)args->address;
508 struct sockaddr_in *sin =
509 (struct sockaddr_in *)args->address;
510 struct sockaddr_in6 *sin6 =
511 (struct sockaddr_in6 *)args->address;
512
513 servername[0] = '\0';
514 switch (args->address->sa_family) {
515 case AF_LOCAL:
516 snprintf(servername, sizeof(servername), "%s",
517 sun->sun_path);
518 break;
519 case AF_INET:
520 snprintf(servername, sizeof(servername), "%pI4",
521 &sin->sin_addr.s_addr);
522 break;
523 case AF_INET6:
524 snprintf(servername, sizeof(servername), "%pI6",
525 &sin6->sin6_addr);
526 break;
527 default:
528 /* caller wants default server name, but
529 * address family isn't recognized. */
530 return ERR_PTR(-EINVAL);
531 }
532 xprtargs.servername = servername;
533 }
534
535 xprt = xprt_create_transport(&xprtargs);
536 if (IS_ERR(xprt))
537 return (struct rpc_clnt *)xprt;
538
539 /*
540 * By default, kernel RPC client connects from a reserved port.
541 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
542 * but it is always enabled for rpciod, which handles the connect
543 * operation.
544 */
545 xprt->resvport = 1;
546 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
547 xprt->resvport = 0;
548
549 return rpc_create_xprt(args, xprt);
550 }
551 EXPORT_SYMBOL_GPL(rpc_create);
552
553 /*
554 * This function clones the RPC client structure. It allows us to share the
555 * same transport while varying parameters such as the authentication
556 * flavour.
557 */
558 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
559 struct rpc_clnt *clnt)
560 {
561 struct rpc_xprt *xprt;
562 struct rpc_clnt *new;
563 int err;
564
565 err = -ENOMEM;
566 rcu_read_lock();
567 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
568 rcu_read_unlock();
569 if (xprt == NULL)
570 goto out_err;
571 args->servername = xprt->servername;
572
573 new = rpc_new_client(args, xprt, clnt);
574 if (IS_ERR(new)) {
575 err = PTR_ERR(new);
576 goto out_err;
577 }
578
579 /* Turn off autobind on clones */
580 new->cl_autobind = 0;
581 new->cl_softrtry = clnt->cl_softrtry;
582 new->cl_discrtry = clnt->cl_discrtry;
583 new->cl_chatty = clnt->cl_chatty;
584 return new;
585
586 out_err:
587 dprintk("RPC: %s: returned error %d\n", __func__, err);
588 return ERR_PTR(err);
589 }
590
591 /**
592 * rpc_clone_client - Clone an RPC client structure
593 *
594 * @clnt: RPC client whose parameters are copied
595 *
596 * Returns a fresh RPC client or an ERR_PTR.
597 */
598 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
599 {
600 struct rpc_create_args args = {
601 .program = clnt->cl_program,
602 .prognumber = clnt->cl_prog,
603 .version = clnt->cl_vers,
604 .authflavor = clnt->cl_auth->au_flavor,
605 };
606 return __rpc_clone_client(&args, clnt);
607 }
608 EXPORT_SYMBOL_GPL(rpc_clone_client);
609
610 /**
611 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
612 *
613 * @clnt: RPC client whose parameters are copied
614 * @flavor: security flavor for new client
615 *
616 * Returns a fresh RPC client or an ERR_PTR.
617 */
618 struct rpc_clnt *
619 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
620 {
621 struct rpc_create_args args = {
622 .program = clnt->cl_program,
623 .prognumber = clnt->cl_prog,
624 .version = clnt->cl_vers,
625 .authflavor = flavor,
626 };
627 return __rpc_clone_client(&args, clnt);
628 }
629 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
630
631 /**
632 * rpc_switch_client_transport: switch the RPC transport on the fly
633 * @clnt: pointer to a struct rpc_clnt
634 * @args: pointer to the new transport arguments
635 * @timeout: pointer to the new timeout parameters
636 *
637 * This function allows the caller to switch the RPC transport for the
638 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
639 * server, for instance. It assumes that the caller has ensured that
640 * there are no active RPC tasks by using some form of locking.
641 *
642 * Returns zero if "clnt" is now using the new xprt. Otherwise a
643 * negative errno is returned, and "clnt" continues to use the old
644 * xprt.
645 */
646 int rpc_switch_client_transport(struct rpc_clnt *clnt,
647 struct xprt_create *args,
648 const struct rpc_timeout *timeout)
649 {
650 const struct rpc_timeout *old_timeo;
651 rpc_authflavor_t pseudoflavor;
652 struct rpc_xprt *xprt, *old;
653 struct rpc_clnt *parent;
654 int err;
655
656 xprt = xprt_create_transport(args);
657 if (IS_ERR(xprt)) {
658 dprintk("RPC: failed to create new xprt for clnt %p\n",
659 clnt);
660 return PTR_ERR(xprt);
661 }
662
663 pseudoflavor = clnt->cl_auth->au_flavor;
664
665 old_timeo = clnt->cl_timeout;
666 old = rpc_clnt_set_transport(clnt, xprt, timeout);
667
668 rpc_unregister_client(clnt);
669 __rpc_clnt_remove_pipedir(clnt);
670
671 /*
672 * A new transport was created. "clnt" therefore
673 * becomes the root of a new cl_parent tree. clnt's
674 * children, if it has any, still point to the old xprt.
675 */
676 parent = clnt->cl_parent;
677 clnt->cl_parent = clnt;
678
679 /*
680 * The old rpc_auth cache cannot be re-used. GSS
681 * contexts in particular are between a single
682 * client and server.
683 */
684 err = rpc_client_register(clnt, pseudoflavor, NULL);
685 if (err)
686 goto out_revert;
687
688 synchronize_rcu();
689 if (parent != clnt)
690 rpc_release_client(parent);
691 xprt_put(old);
692 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
693 return 0;
694
695 out_revert:
696 rpc_clnt_set_transport(clnt, old, old_timeo);
697 clnt->cl_parent = parent;
698 rpc_client_register(clnt, pseudoflavor, NULL);
699 xprt_put(xprt);
700 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
701 return err;
702 }
703 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
704
705 /*
706 * Kill all tasks for the given client.
707 * XXX: kill their descendants as well?
708 */
709 void rpc_killall_tasks(struct rpc_clnt *clnt)
710 {
711 struct rpc_task *rovr;
712
713
714 if (list_empty(&clnt->cl_tasks))
715 return;
716 dprintk("RPC: killing all tasks for client %p\n", clnt);
717 /*
718 * Spin lock all_tasks to prevent changes...
719 */
720 spin_lock(&clnt->cl_lock);
721 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
722 if (!RPC_IS_ACTIVATED(rovr))
723 continue;
724 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
725 rovr->tk_flags |= RPC_TASK_KILLED;
726 rpc_exit(rovr, -EIO);
727 if (RPC_IS_QUEUED(rovr))
728 rpc_wake_up_queued_task(rovr->tk_waitqueue,
729 rovr);
730 }
731 }
732 spin_unlock(&clnt->cl_lock);
733 }
734 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
735
736 /*
737 * Properly shut down an RPC client, terminating all outstanding
738 * requests.
739 */
740 void rpc_shutdown_client(struct rpc_clnt *clnt)
741 {
742 might_sleep();
743
744 dprintk_rcu("RPC: shutting down %s client for %s\n",
745 clnt->cl_program->name,
746 rcu_dereference(clnt->cl_xprt)->servername);
747
748 while (!list_empty(&clnt->cl_tasks)) {
749 rpc_killall_tasks(clnt);
750 wait_event_timeout(destroy_wait,
751 list_empty(&clnt->cl_tasks), 1*HZ);
752 }
753
754 rpc_release_client(clnt);
755 }
756 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
757
758 /*
759 * Free an RPC client
760 */
761 static struct rpc_clnt *
762 rpc_free_client(struct rpc_clnt *clnt)
763 {
764 struct rpc_clnt *parent = NULL;
765
766 dprintk_rcu("RPC: destroying %s client for %s\n",
767 clnt->cl_program->name,
768 rcu_dereference(clnt->cl_xprt)->servername);
769 if (clnt->cl_parent != clnt)
770 parent = clnt->cl_parent;
771 rpc_clnt_remove_pipedir(clnt);
772 rpc_unregister_client(clnt);
773 rpc_free_iostats(clnt->cl_metrics);
774 clnt->cl_metrics = NULL;
775 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
776 rpciod_down();
777 rpc_free_clid(clnt);
778 kfree(clnt);
779 return parent;
780 }
781
782 /*
783 * Free an RPC client
784 */
785 static struct rpc_clnt *
786 rpc_free_auth(struct rpc_clnt *clnt)
787 {
788 if (clnt->cl_auth == NULL)
789 return rpc_free_client(clnt);
790
791 /*
792 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
793 * release remaining GSS contexts. This mechanism ensures
794 * that it can do so safely.
795 */
796 atomic_inc(&clnt->cl_count);
797 rpcauth_release(clnt->cl_auth);
798 clnt->cl_auth = NULL;
799 if (atomic_dec_and_test(&clnt->cl_count))
800 return rpc_free_client(clnt);
801 return NULL;
802 }
803
804 /*
805 * Release reference to the RPC client
806 */
807 void
808 rpc_release_client(struct rpc_clnt *clnt)
809 {
810 dprintk("RPC: rpc_release_client(%p)\n", clnt);
811
812 do {
813 if (list_empty(&clnt->cl_tasks))
814 wake_up(&destroy_wait);
815 if (!atomic_dec_and_test(&clnt->cl_count))
816 break;
817 clnt = rpc_free_auth(clnt);
818 } while (clnt != NULL);
819 }
820 EXPORT_SYMBOL_GPL(rpc_release_client);
821
822 /**
823 * rpc_bind_new_program - bind a new RPC program to an existing client
824 * @old: old rpc_client
825 * @program: rpc program to set
826 * @vers: rpc program version
827 *
828 * Clones the rpc client and sets up a new RPC program. This is mainly
829 * of use for enabling different RPC programs to share the same transport.
830 * The Sun NFSv2/v3 ACL protocol can do this.
831 */
832 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
833 const struct rpc_program *program,
834 u32 vers)
835 {
836 struct rpc_create_args args = {
837 .program = program,
838 .prognumber = program->number,
839 .version = vers,
840 .authflavor = old->cl_auth->au_flavor,
841 };
842 struct rpc_clnt *clnt;
843 int err;
844
845 clnt = __rpc_clone_client(&args, old);
846 if (IS_ERR(clnt))
847 goto out;
848 err = rpc_ping(clnt);
849 if (err != 0) {
850 rpc_shutdown_client(clnt);
851 clnt = ERR_PTR(err);
852 }
853 out:
854 return clnt;
855 }
856 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
857
858 void rpc_task_release_client(struct rpc_task *task)
859 {
860 struct rpc_clnt *clnt = task->tk_client;
861
862 if (clnt != NULL) {
863 /* Remove from client task list */
864 spin_lock(&clnt->cl_lock);
865 list_del(&task->tk_task);
866 spin_unlock(&clnt->cl_lock);
867 task->tk_client = NULL;
868
869 rpc_release_client(clnt);
870 }
871 }
872
873 static
874 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
875 {
876 if (clnt != NULL) {
877 rpc_task_release_client(task);
878 task->tk_client = clnt;
879 atomic_inc(&clnt->cl_count);
880 if (clnt->cl_softrtry)
881 task->tk_flags |= RPC_TASK_SOFT;
882 if (clnt->cl_noretranstimeo)
883 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
884 if (sk_memalloc_socks()) {
885 struct rpc_xprt *xprt;
886
887 rcu_read_lock();
888 xprt = rcu_dereference(clnt->cl_xprt);
889 if (xprt->swapper)
890 task->tk_flags |= RPC_TASK_SWAPPER;
891 rcu_read_unlock();
892 }
893 /* Add to the client's list of all tasks */
894 spin_lock(&clnt->cl_lock);
895 list_add_tail(&task->tk_task, &clnt->cl_tasks);
896 spin_unlock(&clnt->cl_lock);
897 }
898 }
899
900 void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
901 {
902 rpc_task_release_client(task);
903 rpc_task_set_client(task, clnt);
904 }
905 EXPORT_SYMBOL_GPL(rpc_task_reset_client);
906
907
908 static void
909 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
910 {
911 if (msg != NULL) {
912 task->tk_msg.rpc_proc = msg->rpc_proc;
913 task->tk_msg.rpc_argp = msg->rpc_argp;
914 task->tk_msg.rpc_resp = msg->rpc_resp;
915 if (msg->rpc_cred != NULL)
916 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
917 }
918 }
919
920 /*
921 * Default callback for async RPC calls
922 */
923 static void
924 rpc_default_callback(struct rpc_task *task, void *data)
925 {
926 }
927
928 static const struct rpc_call_ops rpc_default_ops = {
929 .rpc_call_done = rpc_default_callback,
930 };
931
932 /**
933 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
934 * @task_setup_data: pointer to task initialisation data
935 */
936 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
937 {
938 struct rpc_task *task;
939
940 task = rpc_new_task(task_setup_data);
941 if (IS_ERR(task))
942 goto out;
943
944 rpc_task_set_client(task, task_setup_data->rpc_client);
945 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
946
947 if (task->tk_action == NULL)
948 rpc_call_start(task);
949
950 atomic_inc(&task->tk_count);
951 rpc_execute(task);
952 out:
953 return task;
954 }
955 EXPORT_SYMBOL_GPL(rpc_run_task);
956
957 /**
958 * rpc_call_sync - Perform a synchronous RPC call
959 * @clnt: pointer to RPC client
960 * @msg: RPC call parameters
961 * @flags: RPC call flags
962 */
963 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
964 {
965 struct rpc_task *task;
966 struct rpc_task_setup task_setup_data = {
967 .rpc_client = clnt,
968 .rpc_message = msg,
969 .callback_ops = &rpc_default_ops,
970 .flags = flags,
971 };
972 int status;
973
974 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
975 if (flags & RPC_TASK_ASYNC) {
976 rpc_release_calldata(task_setup_data.callback_ops,
977 task_setup_data.callback_data);
978 return -EINVAL;
979 }
980
981 task = rpc_run_task(&task_setup_data);
982 if (IS_ERR(task))
983 return PTR_ERR(task);
984 status = task->tk_status;
985 rpc_put_task(task);
986 return status;
987 }
988 EXPORT_SYMBOL_GPL(rpc_call_sync);
989
990 /**
991 * rpc_call_async - Perform an asynchronous RPC call
992 * @clnt: pointer to RPC client
993 * @msg: RPC call parameters
994 * @flags: RPC call flags
995 * @tk_ops: RPC call ops
996 * @data: user call data
997 */
998 int
999 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1000 const struct rpc_call_ops *tk_ops, void *data)
1001 {
1002 struct rpc_task *task;
1003 struct rpc_task_setup task_setup_data = {
1004 .rpc_client = clnt,
1005 .rpc_message = msg,
1006 .callback_ops = tk_ops,
1007 .callback_data = data,
1008 .flags = flags|RPC_TASK_ASYNC,
1009 };
1010
1011 task = rpc_run_task(&task_setup_data);
1012 if (IS_ERR(task))
1013 return PTR_ERR(task);
1014 rpc_put_task(task);
1015 return 0;
1016 }
1017 EXPORT_SYMBOL_GPL(rpc_call_async);
1018
1019 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1020 /**
1021 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1022 * rpc_execute against it
1023 * @req: RPC request
1024 * @tk_ops: RPC call ops
1025 */
1026 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1027 const struct rpc_call_ops *tk_ops)
1028 {
1029 struct rpc_task *task;
1030 struct xdr_buf *xbufp = &req->rq_snd_buf;
1031 struct rpc_task_setup task_setup_data = {
1032 .callback_ops = tk_ops,
1033 };
1034
1035 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1036 /*
1037 * Create an rpc_task to send the data
1038 */
1039 task = rpc_new_task(&task_setup_data);
1040 if (IS_ERR(task)) {
1041 xprt_free_bc_request(req);
1042 goto out;
1043 }
1044 task->tk_rqstp = req;
1045
1046 /*
1047 * Set up the xdr_buf length.
1048 * This also indicates that the buffer is XDR encoded already.
1049 */
1050 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
1051 xbufp->tail[0].iov_len;
1052
1053 task->tk_action = call_bc_transmit;
1054 atomic_inc(&task->tk_count);
1055 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1056 rpc_execute(task);
1057
1058 out:
1059 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1060 return task;
1061 }
1062 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1063
1064 void
1065 rpc_call_start(struct rpc_task *task)
1066 {
1067 task->tk_action = call_start;
1068 }
1069 EXPORT_SYMBOL_GPL(rpc_call_start);
1070
1071 /**
1072 * rpc_peeraddr - extract remote peer address from clnt's xprt
1073 * @clnt: RPC client structure
1074 * @buf: target buffer
1075 * @bufsize: length of target buffer
1076 *
1077 * Returns the number of bytes that are actually in the stored address.
1078 */
1079 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1080 {
1081 size_t bytes;
1082 struct rpc_xprt *xprt;
1083
1084 rcu_read_lock();
1085 xprt = rcu_dereference(clnt->cl_xprt);
1086
1087 bytes = xprt->addrlen;
1088 if (bytes > bufsize)
1089 bytes = bufsize;
1090 memcpy(buf, &xprt->addr, bytes);
1091 rcu_read_unlock();
1092
1093 return bytes;
1094 }
1095 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1096
1097 /**
1098 * rpc_peeraddr2str - return remote peer address in printable format
1099 * @clnt: RPC client structure
1100 * @format: address format
1101 *
1102 * NB: the lifetime of the memory referenced by the returned pointer is
1103 * the same as the rpc_xprt itself. As long as the caller uses this
1104 * pointer, it must hold the RCU read lock.
1105 */
1106 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1107 enum rpc_display_format_t format)
1108 {
1109 struct rpc_xprt *xprt;
1110
1111 xprt = rcu_dereference(clnt->cl_xprt);
1112
1113 if (xprt->address_strings[format] != NULL)
1114 return xprt->address_strings[format];
1115 else
1116 return "unprintable";
1117 }
1118 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1119
1120 static const struct sockaddr_in rpc_inaddr_loopback = {
1121 .sin_family = AF_INET,
1122 .sin_addr.s_addr = htonl(INADDR_ANY),
1123 };
1124
1125 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1126 .sin6_family = AF_INET6,
1127 .sin6_addr = IN6ADDR_ANY_INIT,
1128 };
1129
1130 /*
1131 * Try a getsockname() on a connected datagram socket. Using a
1132 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1133 * This conserves the ephemeral port number space.
1134 *
1135 * Returns zero and fills in "buf" if successful; otherwise, a
1136 * negative errno is returned.
1137 */
1138 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1139 struct sockaddr *buf, int buflen)
1140 {
1141 struct socket *sock;
1142 int err;
1143
1144 err = __sock_create(net, sap->sa_family,
1145 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1146 if (err < 0) {
1147 dprintk("RPC: can't create UDP socket (%d)\n", err);
1148 goto out;
1149 }
1150
1151 switch (sap->sa_family) {
1152 case AF_INET:
1153 err = kernel_bind(sock,
1154 (struct sockaddr *)&rpc_inaddr_loopback,
1155 sizeof(rpc_inaddr_loopback));
1156 break;
1157 case AF_INET6:
1158 err = kernel_bind(sock,
1159 (struct sockaddr *)&rpc_in6addr_loopback,
1160 sizeof(rpc_in6addr_loopback));
1161 break;
1162 default:
1163 err = -EAFNOSUPPORT;
1164 goto out;
1165 }
1166 if (err < 0) {
1167 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1168 goto out_release;
1169 }
1170
1171 err = kernel_connect(sock, sap, salen, 0);
1172 if (err < 0) {
1173 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1174 goto out_release;
1175 }
1176
1177 err = kernel_getsockname(sock, buf, &buflen);
1178 if (err < 0) {
1179 dprintk("RPC: getsockname failed (%d)\n", err);
1180 goto out_release;
1181 }
1182
1183 err = 0;
1184 if (buf->sa_family == AF_INET6) {
1185 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1186 sin6->sin6_scope_id = 0;
1187 }
1188 dprintk("RPC: %s succeeded\n", __func__);
1189
1190 out_release:
1191 sock_release(sock);
1192 out:
1193 return err;
1194 }
1195
1196 /*
1197 * Scraping a connected socket failed, so we don't have a useable
1198 * local address. Fallback: generate an address that will prevent
1199 * the server from calling us back.
1200 *
1201 * Returns zero and fills in "buf" if successful; otherwise, a
1202 * negative errno is returned.
1203 */
1204 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1205 {
1206 switch (family) {
1207 case AF_INET:
1208 if (buflen < sizeof(rpc_inaddr_loopback))
1209 return -EINVAL;
1210 memcpy(buf, &rpc_inaddr_loopback,
1211 sizeof(rpc_inaddr_loopback));
1212 break;
1213 case AF_INET6:
1214 if (buflen < sizeof(rpc_in6addr_loopback))
1215 return -EINVAL;
1216 memcpy(buf, &rpc_in6addr_loopback,
1217 sizeof(rpc_in6addr_loopback));
1218 default:
1219 dprintk("RPC: %s: address family not supported\n",
1220 __func__);
1221 return -EAFNOSUPPORT;
1222 }
1223 dprintk("RPC: %s: succeeded\n", __func__);
1224 return 0;
1225 }
1226
1227 /**
1228 * rpc_localaddr - discover local endpoint address for an RPC client
1229 * @clnt: RPC client structure
1230 * @buf: target buffer
1231 * @buflen: size of target buffer, in bytes
1232 *
1233 * Returns zero and fills in "buf" and "buflen" if successful;
1234 * otherwise, a negative errno is returned.
1235 *
1236 * This works even if the underlying transport is not currently connected,
1237 * or if the upper layer never previously provided a source address.
1238 *
1239 * The result of this function call is transient: multiple calls in
1240 * succession may give different results, depending on how local
1241 * networking configuration changes over time.
1242 */
1243 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1244 {
1245 struct sockaddr_storage address;
1246 struct sockaddr *sap = (struct sockaddr *)&address;
1247 struct rpc_xprt *xprt;
1248 struct net *net;
1249 size_t salen;
1250 int err;
1251
1252 rcu_read_lock();
1253 xprt = rcu_dereference(clnt->cl_xprt);
1254 salen = xprt->addrlen;
1255 memcpy(sap, &xprt->addr, salen);
1256 net = get_net(xprt->xprt_net);
1257 rcu_read_unlock();
1258
1259 rpc_set_port(sap, 0);
1260 err = rpc_sockname(net, sap, salen, buf, buflen);
1261 put_net(net);
1262 if (err != 0)
1263 /* Couldn't discover local address, return ANYADDR */
1264 return rpc_anyaddr(sap->sa_family, buf, buflen);
1265 return 0;
1266 }
1267 EXPORT_SYMBOL_GPL(rpc_localaddr);
1268
1269 void
1270 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1271 {
1272 struct rpc_xprt *xprt;
1273
1274 rcu_read_lock();
1275 xprt = rcu_dereference(clnt->cl_xprt);
1276 if (xprt->ops->set_buffer_size)
1277 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1278 rcu_read_unlock();
1279 }
1280 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1281
1282 /**
1283 * rpc_protocol - Get transport protocol number for an RPC client
1284 * @clnt: RPC client to query
1285 *
1286 */
1287 int rpc_protocol(struct rpc_clnt *clnt)
1288 {
1289 int protocol;
1290
1291 rcu_read_lock();
1292 protocol = rcu_dereference(clnt->cl_xprt)->prot;
1293 rcu_read_unlock();
1294 return protocol;
1295 }
1296 EXPORT_SYMBOL_GPL(rpc_protocol);
1297
1298 /**
1299 * rpc_net_ns - Get the network namespace for this RPC client
1300 * @clnt: RPC client to query
1301 *
1302 */
1303 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1304 {
1305 struct net *ret;
1306
1307 rcu_read_lock();
1308 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1309 rcu_read_unlock();
1310 return ret;
1311 }
1312 EXPORT_SYMBOL_GPL(rpc_net_ns);
1313
1314 /**
1315 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1316 * @clnt: RPC client to query
1317 *
1318 * For stream transports, this is one RPC record fragment (see RFC
1319 * 1831), as we don't support multi-record requests yet. For datagram
1320 * transports, this is the size of an IP packet minus the IP, UDP, and
1321 * RPC header sizes.
1322 */
1323 size_t rpc_max_payload(struct rpc_clnt *clnt)
1324 {
1325 size_t ret;
1326
1327 rcu_read_lock();
1328 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1329 rcu_read_unlock();
1330 return ret;
1331 }
1332 EXPORT_SYMBOL_GPL(rpc_max_payload);
1333
1334 /**
1335 * rpc_get_timeout - Get timeout for transport in units of HZ
1336 * @clnt: RPC client to query
1337 */
1338 unsigned long rpc_get_timeout(struct rpc_clnt *clnt)
1339 {
1340 unsigned long ret;
1341
1342 rcu_read_lock();
1343 ret = rcu_dereference(clnt->cl_xprt)->timeout->to_initval;
1344 rcu_read_unlock();
1345 return ret;
1346 }
1347 EXPORT_SYMBOL_GPL(rpc_get_timeout);
1348
1349 /**
1350 * rpc_force_rebind - force transport to check that remote port is unchanged
1351 * @clnt: client to rebind
1352 *
1353 */
1354 void rpc_force_rebind(struct rpc_clnt *clnt)
1355 {
1356 if (clnt->cl_autobind) {
1357 rcu_read_lock();
1358 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1359 rcu_read_unlock();
1360 }
1361 }
1362 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1363
1364 /*
1365 * Restart an (async) RPC call from the call_prepare state.
1366 * Usually called from within the exit handler.
1367 */
1368 int
1369 rpc_restart_call_prepare(struct rpc_task *task)
1370 {
1371 if (RPC_ASSASSINATED(task))
1372 return 0;
1373 task->tk_action = call_start;
1374 task->tk_status = 0;
1375 if (task->tk_ops->rpc_call_prepare != NULL)
1376 task->tk_action = rpc_prepare_task;
1377 return 1;
1378 }
1379 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1380
1381 /*
1382 * Restart an (async) RPC call. Usually called from within the
1383 * exit handler.
1384 */
1385 int
1386 rpc_restart_call(struct rpc_task *task)
1387 {
1388 if (RPC_ASSASSINATED(task))
1389 return 0;
1390 task->tk_action = call_start;
1391 task->tk_status = 0;
1392 return 1;
1393 }
1394 EXPORT_SYMBOL_GPL(rpc_restart_call);
1395
1396 #ifdef RPC_DEBUG
1397 static const char *rpc_proc_name(const struct rpc_task *task)
1398 {
1399 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1400
1401 if (proc) {
1402 if (proc->p_name)
1403 return proc->p_name;
1404 else
1405 return "NULL";
1406 } else
1407 return "no proc";
1408 }
1409 #endif
1410
1411 /*
1412 * 0. Initial state
1413 *
1414 * Other FSM states can be visited zero or more times, but
1415 * this state is visited exactly once for each RPC.
1416 */
1417 static void
1418 call_start(struct rpc_task *task)
1419 {
1420 struct rpc_clnt *clnt = task->tk_client;
1421
1422 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1423 clnt->cl_program->name, clnt->cl_vers,
1424 rpc_proc_name(task),
1425 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1426
1427 /* Increment call count */
1428 task->tk_msg.rpc_proc->p_count++;
1429 clnt->cl_stats->rpccnt++;
1430 task->tk_action = call_reserve;
1431 }
1432
1433 /*
1434 * 1. Reserve an RPC call slot
1435 */
1436 static void
1437 call_reserve(struct rpc_task *task)
1438 {
1439 dprint_status(task);
1440
1441 task->tk_status = 0;
1442 task->tk_action = call_reserveresult;
1443 xprt_reserve(task);
1444 }
1445
1446 static void call_retry_reserve(struct rpc_task *task);
1447
1448 /*
1449 * 1b. Grok the result of xprt_reserve()
1450 */
1451 static void
1452 call_reserveresult(struct rpc_task *task)
1453 {
1454 int status = task->tk_status;
1455
1456 dprint_status(task);
1457
1458 /*
1459 * After a call to xprt_reserve(), we must have either
1460 * a request slot or else an error status.
1461 */
1462 task->tk_status = 0;
1463 if (status >= 0) {
1464 if (task->tk_rqstp) {
1465 task->tk_action = call_refresh;
1466 return;
1467 }
1468
1469 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
1470 __func__, status);
1471 rpc_exit(task, -EIO);
1472 return;
1473 }
1474
1475 /*
1476 * Even though there was an error, we may have acquired
1477 * a request slot somehow. Make sure not to leak it.
1478 */
1479 if (task->tk_rqstp) {
1480 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
1481 __func__, status);
1482 xprt_release(task);
1483 }
1484
1485 switch (status) {
1486 case -ENOMEM:
1487 rpc_delay(task, HZ >> 2);
1488 case -EAGAIN: /* woken up; retry */
1489 task->tk_action = call_retry_reserve;
1490 return;
1491 case -EIO: /* probably a shutdown */
1492 break;
1493 default:
1494 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
1495 __func__, status);
1496 break;
1497 }
1498 rpc_exit(task, status);
1499 }
1500
1501 /*
1502 * 1c. Retry reserving an RPC call slot
1503 */
1504 static void
1505 call_retry_reserve(struct rpc_task *task)
1506 {
1507 dprint_status(task);
1508
1509 task->tk_status = 0;
1510 task->tk_action = call_reserveresult;
1511 xprt_retry_reserve(task);
1512 }
1513
1514 /*
1515 * 2. Bind and/or refresh the credentials
1516 */
1517 static void
1518 call_refresh(struct rpc_task *task)
1519 {
1520 dprint_status(task);
1521
1522 task->tk_action = call_refreshresult;
1523 task->tk_status = 0;
1524 task->tk_client->cl_stats->rpcauthrefresh++;
1525 rpcauth_refreshcred(task);
1526 }
1527
1528 /*
1529 * 2a. Process the results of a credential refresh
1530 */
1531 static void
1532 call_refreshresult(struct rpc_task *task)
1533 {
1534 int status = task->tk_status;
1535
1536 dprint_status(task);
1537
1538 task->tk_status = 0;
1539 task->tk_action = call_refresh;
1540 switch (status) {
1541 case 0:
1542 if (rpcauth_uptodatecred(task)) {
1543 task->tk_action = call_allocate;
1544 return;
1545 }
1546 /* Use rate-limiting and a max number of retries if refresh
1547 * had status 0 but failed to update the cred.
1548 */
1549 case -ETIMEDOUT:
1550 rpc_delay(task, 3*HZ);
1551 case -EAGAIN:
1552 status = -EACCES;
1553 case -EKEYEXPIRED:
1554 if (!task->tk_cred_retry)
1555 break;
1556 task->tk_cred_retry--;
1557 dprintk("RPC: %5u %s: retry refresh creds\n",
1558 task->tk_pid, __func__);
1559 return;
1560 }
1561 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1562 task->tk_pid, __func__, status);
1563 rpc_exit(task, status);
1564 }
1565
1566 /*
1567 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1568 * (Note: buffer memory is freed in xprt_release).
1569 */
1570 static void
1571 call_allocate(struct rpc_task *task)
1572 {
1573 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1574 struct rpc_rqst *req = task->tk_rqstp;
1575 struct rpc_xprt *xprt = req->rq_xprt;
1576 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1577
1578 dprint_status(task);
1579
1580 task->tk_status = 0;
1581 task->tk_action = call_bind;
1582
1583 if (req->rq_buffer)
1584 return;
1585
1586 if (proc->p_proc != 0) {
1587 BUG_ON(proc->p_arglen == 0);
1588 if (proc->p_decode != NULL)
1589 BUG_ON(proc->p_replen == 0);
1590 }
1591
1592 /*
1593 * Calculate the size (in quads) of the RPC call
1594 * and reply headers, and convert both values
1595 * to byte sizes.
1596 */
1597 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1598 req->rq_callsize <<= 2;
1599 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1600 req->rq_rcvsize <<= 2;
1601
1602 req->rq_buffer = xprt->ops->buf_alloc(task,
1603 req->rq_callsize + req->rq_rcvsize);
1604 if (req->rq_buffer != NULL)
1605 return;
1606
1607 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1608
1609 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1610 task->tk_action = call_allocate;
1611 rpc_delay(task, HZ>>4);
1612 return;
1613 }
1614
1615 rpc_exit(task, -ERESTARTSYS);
1616 }
1617
1618 static inline int
1619 rpc_task_need_encode(struct rpc_task *task)
1620 {
1621 return task->tk_rqstp->rq_snd_buf.len == 0;
1622 }
1623
1624 static inline void
1625 rpc_task_force_reencode(struct rpc_task *task)
1626 {
1627 task->tk_rqstp->rq_snd_buf.len = 0;
1628 task->tk_rqstp->rq_bytes_sent = 0;
1629 }
1630
1631 static inline void
1632 rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1633 {
1634 buf->head[0].iov_base = start;
1635 buf->head[0].iov_len = len;
1636 buf->tail[0].iov_len = 0;
1637 buf->page_len = 0;
1638 buf->flags = 0;
1639 buf->len = 0;
1640 buf->buflen = len;
1641 }
1642
1643 /*
1644 * 3. Encode arguments of an RPC call
1645 */
1646 static void
1647 rpc_xdr_encode(struct rpc_task *task)
1648 {
1649 struct rpc_rqst *req = task->tk_rqstp;
1650 kxdreproc_t encode;
1651 __be32 *p;
1652
1653 dprint_status(task);
1654
1655 rpc_xdr_buf_init(&req->rq_snd_buf,
1656 req->rq_buffer,
1657 req->rq_callsize);
1658 rpc_xdr_buf_init(&req->rq_rcv_buf,
1659 (char *)req->rq_buffer + req->rq_callsize,
1660 req->rq_rcvsize);
1661
1662 p = rpc_encode_header(task);
1663 if (p == NULL) {
1664 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1665 rpc_exit(task, -EIO);
1666 return;
1667 }
1668
1669 encode = task->tk_msg.rpc_proc->p_encode;
1670 if (encode == NULL)
1671 return;
1672
1673 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1674 task->tk_msg.rpc_argp);
1675 }
1676
1677 /*
1678 * 4. Get the server port number if not yet set
1679 */
1680 static void
1681 call_bind(struct rpc_task *task)
1682 {
1683 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1684
1685 dprint_status(task);
1686
1687 task->tk_action = call_connect;
1688 if (!xprt_bound(xprt)) {
1689 task->tk_action = call_bind_status;
1690 task->tk_timeout = xprt->bind_timeout;
1691 xprt->ops->rpcbind(task);
1692 }
1693 }
1694
1695 /*
1696 * 4a. Sort out bind result
1697 */
1698 static void
1699 call_bind_status(struct rpc_task *task)
1700 {
1701 int status = -EIO;
1702
1703 if (task->tk_status >= 0) {
1704 dprint_status(task);
1705 task->tk_status = 0;
1706 task->tk_action = call_connect;
1707 return;
1708 }
1709
1710 trace_rpc_bind_status(task);
1711 switch (task->tk_status) {
1712 case -ENOMEM:
1713 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1714 rpc_delay(task, HZ >> 2);
1715 goto retry_timeout;
1716 case -EACCES:
1717 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1718 "unavailable\n", task->tk_pid);
1719 /* fail immediately if this is an RPC ping */
1720 if (task->tk_msg.rpc_proc->p_proc == 0) {
1721 status = -EOPNOTSUPP;
1722 break;
1723 }
1724 if (task->tk_rebind_retry == 0)
1725 break;
1726 task->tk_rebind_retry--;
1727 rpc_delay(task, 3*HZ);
1728 goto retry_timeout;
1729 case -ETIMEDOUT:
1730 dprintk("RPC: %5u rpcbind request timed out\n",
1731 task->tk_pid);
1732 goto retry_timeout;
1733 case -EPFNOSUPPORT:
1734 /* server doesn't support any rpcbind version we know of */
1735 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1736 task->tk_pid);
1737 break;
1738 case -EPROTONOSUPPORT:
1739 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1740 task->tk_pid);
1741 goto retry_timeout;
1742 case -ECONNREFUSED: /* connection problems */
1743 case -ECONNRESET:
1744 case -ECONNABORTED:
1745 case -ENOTCONN:
1746 case -EHOSTDOWN:
1747 case -EHOSTUNREACH:
1748 case -ENETUNREACH:
1749 case -EPIPE:
1750 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1751 task->tk_pid, task->tk_status);
1752 if (!RPC_IS_SOFTCONN(task)) {
1753 rpc_delay(task, 5*HZ);
1754 goto retry_timeout;
1755 }
1756 status = task->tk_status;
1757 break;
1758 default:
1759 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1760 task->tk_pid, -task->tk_status);
1761 }
1762
1763 rpc_exit(task, status);
1764 return;
1765
1766 retry_timeout:
1767 task->tk_status = 0;
1768 task->tk_action = call_timeout;
1769 }
1770
1771 /*
1772 * 4b. Connect to the RPC server
1773 */
1774 static void
1775 call_connect(struct rpc_task *task)
1776 {
1777 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1778
1779 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1780 task->tk_pid, xprt,
1781 (xprt_connected(xprt) ? "is" : "is not"));
1782
1783 task->tk_action = call_transmit;
1784 if (!xprt_connected(xprt)) {
1785 task->tk_action = call_connect_status;
1786 if (task->tk_status < 0)
1787 return;
1788 if (task->tk_flags & RPC_TASK_NOCONNECT) {
1789 rpc_exit(task, -ENOTCONN);
1790 return;
1791 }
1792 xprt_connect(task);
1793 }
1794 }
1795
1796 /*
1797 * 4c. Sort out connect result
1798 */
1799 static void
1800 call_connect_status(struct rpc_task *task)
1801 {
1802 struct rpc_clnt *clnt = task->tk_client;
1803 int status = task->tk_status;
1804
1805 dprint_status(task);
1806
1807 trace_rpc_connect_status(task, status);
1808 task->tk_status = 0;
1809 switch (status) {
1810 case -ECONNREFUSED:
1811 case -ECONNRESET:
1812 case -ECONNABORTED:
1813 case -ENETUNREACH:
1814 case -EHOSTUNREACH:
1815 if (RPC_IS_SOFTCONN(task))
1816 break;
1817 /* retry with existing socket, after a delay */
1818 rpc_delay(task, 3*HZ);
1819 case -EAGAIN:
1820 /* Check for timeouts before looping back to call_bind */
1821 case -ETIMEDOUT:
1822 task->tk_action = call_timeout;
1823 return;
1824 case 0:
1825 clnt->cl_stats->netreconn++;
1826 task->tk_action = call_transmit;
1827 return;
1828 }
1829 rpc_exit(task, status);
1830 }
1831
1832 /*
1833 * 5. Transmit the RPC request, and wait for reply
1834 */
1835 static void
1836 call_transmit(struct rpc_task *task)
1837 {
1838 int is_retrans = RPC_WAS_SENT(task);
1839
1840 dprint_status(task);
1841
1842 task->tk_action = call_status;
1843 if (task->tk_status < 0)
1844 return;
1845 if (!xprt_prepare_transmit(task))
1846 return;
1847 task->tk_action = call_transmit_status;
1848 /* Encode here so that rpcsec_gss can use correct sequence number. */
1849 if (rpc_task_need_encode(task)) {
1850 rpc_xdr_encode(task);
1851 /* Did the encode result in an error condition? */
1852 if (task->tk_status != 0) {
1853 /* Was the error nonfatal? */
1854 if (task->tk_status == -EAGAIN)
1855 rpc_delay(task, HZ >> 4);
1856 else
1857 rpc_exit(task, task->tk_status);
1858 return;
1859 }
1860 }
1861 xprt_transmit(task);
1862 if (task->tk_status < 0)
1863 return;
1864 if (is_retrans)
1865 task->tk_client->cl_stats->rpcretrans++;
1866 /*
1867 * On success, ensure that we call xprt_end_transmit() before sleeping
1868 * in order to allow access to the socket to other RPC requests.
1869 */
1870 call_transmit_status(task);
1871 if (rpc_reply_expected(task))
1872 return;
1873 task->tk_action = rpc_exit_task;
1874 rpc_wake_up_queued_task(&task->tk_rqstp->rq_xprt->pending, task);
1875 }
1876
1877 /*
1878 * 5a. Handle cleanup after a transmission
1879 */
1880 static void
1881 call_transmit_status(struct rpc_task *task)
1882 {
1883 task->tk_action = call_status;
1884
1885 /*
1886 * Common case: success. Force the compiler to put this
1887 * test first.
1888 */
1889 if (task->tk_status == 0) {
1890 xprt_end_transmit(task);
1891 rpc_task_force_reencode(task);
1892 return;
1893 }
1894
1895 switch (task->tk_status) {
1896 case -EAGAIN:
1897 break;
1898 default:
1899 dprint_status(task);
1900 xprt_end_transmit(task);
1901 rpc_task_force_reencode(task);
1902 break;
1903 /*
1904 * Special cases: if we've been waiting on the
1905 * socket's write_space() callback, or if the
1906 * socket just returned a connection error,
1907 * then hold onto the transport lock.
1908 */
1909 case -ECONNREFUSED:
1910 case -EHOSTDOWN:
1911 case -EHOSTUNREACH:
1912 case -ENETUNREACH:
1913 if (RPC_IS_SOFTCONN(task)) {
1914 xprt_end_transmit(task);
1915 rpc_exit(task, task->tk_status);
1916 break;
1917 }
1918 case -ECONNRESET:
1919 case -ECONNABORTED:
1920 case -ENOTCONN:
1921 case -EPIPE:
1922 rpc_task_force_reencode(task);
1923 }
1924 }
1925
1926 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1927 /*
1928 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1929 * addition, disconnect on connectivity errors.
1930 */
1931 static void
1932 call_bc_transmit(struct rpc_task *task)
1933 {
1934 struct rpc_rqst *req = task->tk_rqstp;
1935
1936 if (!xprt_prepare_transmit(task)) {
1937 /*
1938 * Could not reserve the transport. Try again after the
1939 * transport is released.
1940 */
1941 task->tk_status = 0;
1942 task->tk_action = call_bc_transmit;
1943 return;
1944 }
1945
1946 task->tk_action = rpc_exit_task;
1947 if (task->tk_status < 0) {
1948 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1949 "error: %d\n", task->tk_status);
1950 return;
1951 }
1952
1953 xprt_transmit(task);
1954 xprt_end_transmit(task);
1955 dprint_status(task);
1956 switch (task->tk_status) {
1957 case 0:
1958 /* Success */
1959 break;
1960 case -EHOSTDOWN:
1961 case -EHOSTUNREACH:
1962 case -ENETUNREACH:
1963 case -ETIMEDOUT:
1964 /*
1965 * Problem reaching the server. Disconnect and let the
1966 * forechannel reestablish the connection. The server will
1967 * have to retransmit the backchannel request and we'll
1968 * reprocess it. Since these ops are idempotent, there's no
1969 * need to cache our reply at this time.
1970 */
1971 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1972 "error: %d\n", task->tk_status);
1973 xprt_conditional_disconnect(req->rq_xprt,
1974 req->rq_connect_cookie);
1975 break;
1976 default:
1977 /*
1978 * We were unable to reply and will have to drop the
1979 * request. The server should reconnect and retransmit.
1980 */
1981 WARN_ON_ONCE(task->tk_status == -EAGAIN);
1982 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1983 "error: %d\n", task->tk_status);
1984 break;
1985 }
1986 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1987 }
1988 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1989
1990 /*
1991 * 6. Sort out the RPC call status
1992 */
1993 static void
1994 call_status(struct rpc_task *task)
1995 {
1996 struct rpc_clnt *clnt = task->tk_client;
1997 struct rpc_rqst *req = task->tk_rqstp;
1998 int status;
1999
2000 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
2001 task->tk_status = req->rq_reply_bytes_recvd;
2002
2003 dprint_status(task);
2004
2005 status = task->tk_status;
2006 if (status >= 0) {
2007 task->tk_action = call_decode;
2008 return;
2009 }
2010
2011 trace_rpc_call_status(task);
2012 task->tk_status = 0;
2013 switch(status) {
2014 case -EHOSTDOWN:
2015 case -EHOSTUNREACH:
2016 case -ENETUNREACH:
2017 if (RPC_IS_SOFTCONN(task)) {
2018 rpc_exit(task, status);
2019 break;
2020 }
2021 /*
2022 * Delay any retries for 3 seconds, then handle as if it
2023 * were a timeout.
2024 */
2025 rpc_delay(task, 3*HZ);
2026 case -ETIMEDOUT:
2027 task->tk_action = call_timeout;
2028 if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
2029 && task->tk_client->cl_discrtry)
2030 xprt_conditional_disconnect(req->rq_xprt,
2031 req->rq_connect_cookie);
2032 break;
2033 case -ECONNREFUSED:
2034 case -ECONNRESET:
2035 case -ECONNABORTED:
2036 rpc_force_rebind(clnt);
2037 rpc_delay(task, 3*HZ);
2038 case -EPIPE:
2039 case -ENOTCONN:
2040 task->tk_action = call_bind;
2041 break;
2042 case -EAGAIN:
2043 task->tk_action = call_transmit;
2044 break;
2045 case -EIO:
2046 /* shutdown or soft timeout */
2047 rpc_exit(task, status);
2048 break;
2049 default:
2050 if (clnt->cl_chatty)
2051 printk("%s: RPC call returned error %d\n",
2052 clnt->cl_program->name, -status);
2053 rpc_exit(task, status);
2054 }
2055 }
2056
2057 /*
2058 * 6a. Handle RPC timeout
2059 * We do not release the request slot, so we keep using the
2060 * same XID for all retransmits.
2061 */
2062 static void
2063 call_timeout(struct rpc_task *task)
2064 {
2065 struct rpc_clnt *clnt = task->tk_client;
2066
2067 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
2068 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
2069 goto retry;
2070 }
2071
2072 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2073 task->tk_timeouts++;
2074
2075 if (RPC_IS_SOFTCONN(task)) {
2076 rpc_exit(task, -ETIMEDOUT);
2077 return;
2078 }
2079 if (RPC_IS_SOFT(task)) {
2080 if (clnt->cl_chatty) {
2081 rcu_read_lock();
2082 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
2083 clnt->cl_program->name,
2084 rcu_dereference(clnt->cl_xprt)->servername);
2085 rcu_read_unlock();
2086 }
2087 if (task->tk_flags & RPC_TASK_TIMEOUT)
2088 rpc_exit(task, -ETIMEDOUT);
2089 else
2090 rpc_exit(task, -EIO);
2091 return;
2092 }
2093
2094 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2095 task->tk_flags |= RPC_CALL_MAJORSEEN;
2096 if (clnt->cl_chatty) {
2097 rcu_read_lock();
2098 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
2099 clnt->cl_program->name,
2100 rcu_dereference(clnt->cl_xprt)->servername);
2101 rcu_read_unlock();
2102 }
2103 }
2104 rpc_force_rebind(clnt);
2105 /*
2106 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2107 * event? RFC2203 requires the server to drop all such requests.
2108 */
2109 rpcauth_invalcred(task);
2110
2111 retry:
2112 task->tk_action = call_bind;
2113 task->tk_status = 0;
2114 }
2115
2116 /*
2117 * 7. Decode the RPC reply
2118 */
2119 static void
2120 call_decode(struct rpc_task *task)
2121 {
2122 struct rpc_clnt *clnt = task->tk_client;
2123 struct rpc_rqst *req = task->tk_rqstp;
2124 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
2125 __be32 *p;
2126
2127 dprint_status(task);
2128
2129 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2130 if (clnt->cl_chatty) {
2131 rcu_read_lock();
2132 printk(KERN_NOTICE "%s: server %s OK\n",
2133 clnt->cl_program->name,
2134 rcu_dereference(clnt->cl_xprt)->servername);
2135 rcu_read_unlock();
2136 }
2137 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2138 }
2139
2140 /*
2141 * Ensure that we see all writes made by xprt_complete_rqst()
2142 * before it changed req->rq_reply_bytes_recvd.
2143 */
2144 smp_rmb();
2145 req->rq_rcv_buf.len = req->rq_private_buf.len;
2146
2147 /* Check that the softirq receive buffer is valid */
2148 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2149 sizeof(req->rq_rcv_buf)) != 0);
2150
2151 if (req->rq_rcv_buf.len < 12) {
2152 if (!RPC_IS_SOFT(task)) {
2153 task->tk_action = call_bind;
2154 goto out_retry;
2155 }
2156 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
2157 clnt->cl_program->name, task->tk_status);
2158 task->tk_action = call_timeout;
2159 goto out_retry;
2160 }
2161
2162 p = rpc_verify_header(task);
2163 if (IS_ERR(p)) {
2164 if (p == ERR_PTR(-EAGAIN))
2165 goto out_retry;
2166 return;
2167 }
2168
2169 task->tk_action = rpc_exit_task;
2170
2171 if (decode) {
2172 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
2173 task->tk_msg.rpc_resp);
2174 }
2175 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
2176 task->tk_status);
2177 return;
2178 out_retry:
2179 task->tk_status = 0;
2180 /* Note: rpc_verify_header() may have freed the RPC slot */
2181 if (task->tk_rqstp == req) {
2182 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
2183 if (task->tk_client->cl_discrtry)
2184 xprt_conditional_disconnect(req->rq_xprt,
2185 req->rq_connect_cookie);
2186 }
2187 }
2188
2189 static __be32 *
2190 rpc_encode_header(struct rpc_task *task)
2191 {
2192 struct rpc_clnt *clnt = task->tk_client;
2193 struct rpc_rqst *req = task->tk_rqstp;
2194 __be32 *p = req->rq_svec[0].iov_base;
2195
2196 /* FIXME: check buffer size? */
2197
2198 p = xprt_skip_transport_header(req->rq_xprt, p);
2199 *p++ = req->rq_xid; /* XID */
2200 *p++ = htonl(RPC_CALL); /* CALL */
2201 *p++ = htonl(RPC_VERSION); /* RPC version */
2202 *p++ = htonl(clnt->cl_prog); /* program number */
2203 *p++ = htonl(clnt->cl_vers); /* program version */
2204 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
2205 p = rpcauth_marshcred(task, p);
2206 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
2207 return p;
2208 }
2209
2210 static __be32 *
2211 rpc_verify_header(struct rpc_task *task)
2212 {
2213 struct rpc_clnt *clnt = task->tk_client;
2214 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
2215 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
2216 __be32 *p = iov->iov_base;
2217 u32 n;
2218 int error = -EACCES;
2219
2220 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
2221 /* RFC-1014 says that the representation of XDR data must be a
2222 * multiple of four bytes
2223 * - if it isn't pointer subtraction in the NFS client may give
2224 * undefined results
2225 */
2226 dprintk("RPC: %5u %s: XDR representation not a multiple of"
2227 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
2228 task->tk_rqstp->rq_rcv_buf.len);
2229 error = -EIO;
2230 goto out_err;
2231 }
2232 if ((len -= 3) < 0)
2233 goto out_overflow;
2234
2235 p += 1; /* skip XID */
2236 if ((n = ntohl(*p++)) != RPC_REPLY) {
2237 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
2238 task->tk_pid, __func__, n);
2239 error = -EIO;
2240 goto out_garbage;
2241 }
2242
2243 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
2244 if (--len < 0)
2245 goto out_overflow;
2246 switch ((n = ntohl(*p++))) {
2247 case RPC_AUTH_ERROR:
2248 break;
2249 case RPC_MISMATCH:
2250 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
2251 task->tk_pid, __func__);
2252 error = -EPROTONOSUPPORT;
2253 goto out_err;
2254 default:
2255 dprintk("RPC: %5u %s: RPC call rejected, "
2256 "unknown error: %x\n",
2257 task->tk_pid, __func__, n);
2258 error = -EIO;
2259 goto out_err;
2260 }
2261 if (--len < 0)
2262 goto out_overflow;
2263 switch ((n = ntohl(*p++))) {
2264 case RPC_AUTH_REJECTEDCRED:
2265 case RPC_AUTH_REJECTEDVERF:
2266 case RPCSEC_GSS_CREDPROBLEM:
2267 case RPCSEC_GSS_CTXPROBLEM:
2268 if (!task->tk_cred_retry)
2269 break;
2270 task->tk_cred_retry--;
2271 dprintk("RPC: %5u %s: retry stale creds\n",
2272 task->tk_pid, __func__);
2273 rpcauth_invalcred(task);
2274 /* Ensure we obtain a new XID! */
2275 xprt_release(task);
2276 task->tk_action = call_reserve;
2277 goto out_retry;
2278 case RPC_AUTH_BADCRED:
2279 case RPC_AUTH_BADVERF:
2280 /* possibly garbled cred/verf? */
2281 if (!task->tk_garb_retry)
2282 break;
2283 task->tk_garb_retry--;
2284 dprintk("RPC: %5u %s: retry garbled creds\n",
2285 task->tk_pid, __func__);
2286 task->tk_action = call_bind;
2287 goto out_retry;
2288 case RPC_AUTH_TOOWEAK:
2289 rcu_read_lock();
2290 printk(KERN_NOTICE "RPC: server %s requires stronger "
2291 "authentication.\n",
2292 rcu_dereference(clnt->cl_xprt)->servername);
2293 rcu_read_unlock();
2294 break;
2295 default:
2296 dprintk("RPC: %5u %s: unknown auth error: %x\n",
2297 task->tk_pid, __func__, n);
2298 error = -EIO;
2299 }
2300 dprintk("RPC: %5u %s: call rejected %d\n",
2301 task->tk_pid, __func__, n);
2302 goto out_err;
2303 }
2304 p = rpcauth_checkverf(task, p);
2305 if (IS_ERR(p)) {
2306 error = PTR_ERR(p);
2307 dprintk("RPC: %5u %s: auth check failed with %d\n",
2308 task->tk_pid, __func__, error);
2309 goto out_garbage; /* bad verifier, retry */
2310 }
2311 len = p - (__be32 *)iov->iov_base - 1;
2312 if (len < 0)
2313 goto out_overflow;
2314 switch ((n = ntohl(*p++))) {
2315 case RPC_SUCCESS:
2316 return p;
2317 case RPC_PROG_UNAVAIL:
2318 dprintk_rcu("RPC: %5u %s: program %u is unsupported "
2319 "by server %s\n", task->tk_pid, __func__,
2320 (unsigned int)clnt->cl_prog,
2321 rcu_dereference(clnt->cl_xprt)->servername);
2322 error = -EPFNOSUPPORT;
2323 goto out_err;
2324 case RPC_PROG_MISMATCH:
2325 dprintk_rcu("RPC: %5u %s: program %u, version %u unsupported "
2326 "by server %s\n", task->tk_pid, __func__,
2327 (unsigned int)clnt->cl_prog,
2328 (unsigned int)clnt->cl_vers,
2329 rcu_dereference(clnt->cl_xprt)->servername);
2330 error = -EPROTONOSUPPORT;
2331 goto out_err;
2332 case RPC_PROC_UNAVAIL:
2333 dprintk_rcu("RPC: %5u %s: proc %s unsupported by program %u, "
2334 "version %u on server %s\n",
2335 task->tk_pid, __func__,
2336 rpc_proc_name(task),
2337 clnt->cl_prog, clnt->cl_vers,
2338 rcu_dereference(clnt->cl_xprt)->servername);
2339 error = -EOPNOTSUPP;
2340 goto out_err;
2341 case RPC_GARBAGE_ARGS:
2342 dprintk("RPC: %5u %s: server saw garbage\n",
2343 task->tk_pid, __func__);
2344 break; /* retry */
2345 default:
2346 dprintk("RPC: %5u %s: server accept status: %x\n",
2347 task->tk_pid, __func__, n);
2348 /* Also retry */
2349 }
2350
2351 out_garbage:
2352 clnt->cl_stats->rpcgarbage++;
2353 if (task->tk_garb_retry) {
2354 task->tk_garb_retry--;
2355 dprintk("RPC: %5u %s: retrying\n",
2356 task->tk_pid, __func__);
2357 task->tk_action = call_bind;
2358 out_retry:
2359 return ERR_PTR(-EAGAIN);
2360 }
2361 out_err:
2362 rpc_exit(task, error);
2363 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
2364 __func__, error);
2365 return ERR_PTR(error);
2366 out_overflow:
2367 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
2368 __func__);
2369 goto out_garbage;
2370 }
2371
2372 static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2373 {
2374 }
2375
2376 static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
2377 {
2378 return 0;
2379 }
2380
2381 static struct rpc_procinfo rpcproc_null = {
2382 .p_encode = rpcproc_encode_null,
2383 .p_decode = rpcproc_decode_null,
2384 };
2385
2386 static int rpc_ping(struct rpc_clnt *clnt)
2387 {
2388 struct rpc_message msg = {
2389 .rpc_proc = &rpcproc_null,
2390 };
2391 int err;
2392 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
2393 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
2394 put_rpccred(msg.rpc_cred);
2395 return err;
2396 }
2397
2398 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2399 {
2400 struct rpc_message msg = {
2401 .rpc_proc = &rpcproc_null,
2402 .rpc_cred = cred,
2403 };
2404 struct rpc_task_setup task_setup_data = {
2405 .rpc_client = clnt,
2406 .rpc_message = &msg,
2407 .callback_ops = &rpc_default_ops,
2408 .flags = flags,
2409 };
2410 return rpc_run_task(&task_setup_data);
2411 }
2412 EXPORT_SYMBOL_GPL(rpc_call_null);
2413
2414 #ifdef RPC_DEBUG
2415 static void rpc_show_header(void)
2416 {
2417 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2418 "-timeout ---ops--\n");
2419 }
2420
2421 static void rpc_show_task(const struct rpc_clnt *clnt,
2422 const struct rpc_task *task)
2423 {
2424 const char *rpc_waitq = "none";
2425
2426 if (RPC_IS_QUEUED(task))
2427 rpc_waitq = rpc_qname(task->tk_waitqueue);
2428
2429 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2430 task->tk_pid, task->tk_flags, task->tk_status,
2431 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
2432 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2433 task->tk_action, rpc_waitq);
2434 }
2435
2436 void rpc_show_tasks(struct net *net)
2437 {
2438 struct rpc_clnt *clnt;
2439 struct rpc_task *task;
2440 int header = 0;
2441 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2442
2443 spin_lock(&sn->rpc_client_lock);
2444 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
2445 spin_lock(&clnt->cl_lock);
2446 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
2447 if (!header) {
2448 rpc_show_header();
2449 header++;
2450 }
2451 rpc_show_task(clnt, task);
2452 }
2453 spin_unlock(&clnt->cl_lock);
2454 }
2455 spin_unlock(&sn->rpc_client_lock);
2456 }
2457 #endif
Linux with added FPC-III support