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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.h>
29#include <linux/rcupdate.h>
30#include <linux/utsname.h>
31#include <linux/workqueue.h>
32#include <linux/in.h>
33#include <linux/in6.h>
34#include <linux/un.h>
35
36#include <linux/sunrpc/clnt.h>
37#include <linux/sunrpc/addr.h>
38#include <linux/sunrpc/rpc_pipe_fs.h>
39#include <linux/sunrpc/metrics.h>
40#include <linux/sunrpc/bc_xprt.h>
41#include <trace/events/sunrpc.h>
42
43#include "sunrpc.h"
44#include "netns.h"
45
46#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
47# define RPCDBG_FACILITY RPCDBG_CALL
48#endif
49
50#define dprint_status(t) \
51 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
52 __func__, t->tk_status)
53
54/*
55 * All RPC clients are linked into this list
56 */
57
58static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
59
60
61static void call_start(struct rpc_task *task);
62static void call_reserve(struct rpc_task *task);
63static void call_reserveresult(struct rpc_task *task);
64static void call_allocate(struct rpc_task *task);
65static void call_encode(struct rpc_task *task);
66static void call_decode(struct rpc_task *task);
67static void call_bind(struct rpc_task *task);
68static void call_bind_status(struct rpc_task *task);
69static void call_transmit(struct rpc_task *task);
70static void call_status(struct rpc_task *task);
71static void call_transmit_status(struct rpc_task *task);
72static void call_refresh(struct rpc_task *task);
73static void call_refreshresult(struct rpc_task *task);
74static void call_connect(struct rpc_task *task);
75static void call_connect_status(struct rpc_task *task);
76
77static int rpc_encode_header(struct rpc_task *task,
78 struct xdr_stream *xdr);
79static int rpc_decode_header(struct rpc_task *task,
80 struct xdr_stream *xdr);
81static int rpc_ping(struct rpc_clnt *clnt);
82static void rpc_check_timeout(struct rpc_task *task);
83
84static void rpc_register_client(struct rpc_clnt *clnt)
85{
86 struct net *net = rpc_net_ns(clnt);
87 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
88
89 spin_lock(&sn->rpc_client_lock);
90 list_add(&clnt->cl_clients, &sn->all_clients);
91 spin_unlock(&sn->rpc_client_lock);
92}
93
94static void rpc_unregister_client(struct rpc_clnt *clnt)
95{
96 struct net *net = rpc_net_ns(clnt);
97 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
98
99 spin_lock(&sn->rpc_client_lock);
100 list_del(&clnt->cl_clients);
101 spin_unlock(&sn->rpc_client_lock);
102}
103
104static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
105{
106 rpc_remove_client_dir(clnt);
107}
108
109static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
110{
111 struct net *net = rpc_net_ns(clnt);
112 struct super_block *pipefs_sb;
113
114 pipefs_sb = rpc_get_sb_net(net);
115 if (pipefs_sb) {
116 __rpc_clnt_remove_pipedir(clnt);
117 rpc_put_sb_net(net);
118 }
119}
120
121static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
122 struct rpc_clnt *clnt)
123{
124 static uint32_t clntid;
125 const char *dir_name = clnt->cl_program->pipe_dir_name;
126 char name[15];
127 struct dentry *dir, *dentry;
128
129 dir = rpc_d_lookup_sb(sb, dir_name);
130 if (dir == NULL) {
131 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
132 return dir;
133 }
134 for (;;) {
135 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
136 name[sizeof(name) - 1] = '\0';
137 dentry = rpc_create_client_dir(dir, name, clnt);
138 if (!IS_ERR(dentry))
139 break;
140 if (dentry == ERR_PTR(-EEXIST))
141 continue;
142 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
143 " %s/%s, error %ld\n",
144 dir_name, name, PTR_ERR(dentry));
145 break;
146 }
147 dput(dir);
148 return dentry;
149}
150
151static int
152rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
153{
154 struct dentry *dentry;
155
156 if (clnt->cl_program->pipe_dir_name != NULL) {
157 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
158 if (IS_ERR(dentry))
159 return PTR_ERR(dentry);
160 }
161 return 0;
162}
163
164static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
165{
166 if (clnt->cl_program->pipe_dir_name == NULL)
167 return 1;
168
169 switch (event) {
170 case RPC_PIPEFS_MOUNT:
171 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
172 return 1;
173 if (atomic_read(&clnt->cl_count) == 0)
174 return 1;
175 break;
176 case RPC_PIPEFS_UMOUNT:
177 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
178 return 1;
179 break;
180 }
181 return 0;
182}
183
184static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
185 struct super_block *sb)
186{
187 struct dentry *dentry;
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 0;
205}
206
207static 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
221static 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
237static 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
252static struct notifier_block rpc_clients_block = {
253 .notifier_call = rpc_pipefs_event,
254 .priority = SUNRPC_PIPEFS_RPC_PRIO,
255};
256
257int rpc_clients_notifier_register(void)
258{
259 return rpc_pipefs_notifier_register(&rpc_clients_block);
260}
261
262void rpc_clients_notifier_unregister(void)
263{
264 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
265}
266
267static 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
287static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
288{
289 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
290 nodename, sizeof(clnt->cl_nodename));
291}
292
293static int rpc_client_register(struct rpc_clnt *clnt,
294 rpc_authflavor_t pseudoflavor,
295 const char *client_name)
296{
297 struct rpc_auth_create_args auth_args = {
298 .pseudoflavor = pseudoflavor,
299 .target_name = client_name,
300 };
301 struct rpc_auth *auth;
302 struct net *net = rpc_net_ns(clnt);
303 struct super_block *pipefs_sb;
304 int err;
305
306 rpc_clnt_debugfs_register(clnt);
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;
327err_auth:
328 pipefs_sb = rpc_get_sb_net(net);
329 rpc_unregister_client(clnt);
330 __rpc_clnt_remove_pipedir(clnt);
331out:
332 if (pipefs_sb)
333 rpc_put_sb_net(net);
334 rpc_clnt_debugfs_unregister(clnt);
335 return err;
336}
337
338static DEFINE_IDA(rpc_clids);
339
340void rpc_cleanup_clids(void)
341{
342 ida_destroy(&rpc_clids);
343}
344
345static int rpc_alloc_clid(struct rpc_clnt *clnt)
346{
347 int clid;
348
349 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
350 if (clid < 0)
351 return clid;
352 clnt->cl_clid = clid;
353 return 0;
354}
355
356static void rpc_free_clid(struct rpc_clnt *clnt)
357{
358 ida_simple_remove(&rpc_clids, clnt->cl_clid);
359}
360
361static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
362 struct rpc_xprt_switch *xps,
363 struct rpc_xprt *xprt,
364 struct rpc_clnt *parent)
365{
366 const struct rpc_program *program = args->program;
367 const struct rpc_version *version;
368 struct rpc_clnt *clnt = NULL;
369 const struct rpc_timeout *timeout;
370 const char *nodename = args->nodename;
371 int err;
372
373 err = rpciod_up();
374 if (err)
375 goto out_no_rpciod;
376
377 err = -EINVAL;
378 if (args->version >= program->nrvers)
379 goto out_err;
380 version = program->version[args->version];
381 if (version == NULL)
382 goto out_err;
383
384 err = -ENOMEM;
385 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
386 if (!clnt)
387 goto out_err;
388 clnt->cl_parent = parent ? : clnt;
389
390 err = rpc_alloc_clid(clnt);
391 if (err)
392 goto out_no_clid;
393
394 clnt->cl_cred = get_cred(args->cred);
395 clnt->cl_procinfo = version->procs;
396 clnt->cl_maxproc = version->nrprocs;
397 clnt->cl_prog = args->prognumber ? : program->number;
398 clnt->cl_vers = version->number;
399 clnt->cl_stats = program->stats;
400 clnt->cl_metrics = rpc_alloc_iostats(clnt);
401 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
402 err = -ENOMEM;
403 if (clnt->cl_metrics == NULL)
404 goto out_no_stats;
405 clnt->cl_program = program;
406 INIT_LIST_HEAD(&clnt->cl_tasks);
407 spin_lock_init(&clnt->cl_lock);
408
409 timeout = xprt->timeout;
410 if (args->timeout != NULL) {
411 memcpy(&clnt->cl_timeout_default, args->timeout,
412 sizeof(clnt->cl_timeout_default));
413 timeout = &clnt->cl_timeout_default;
414 }
415
416 rpc_clnt_set_transport(clnt, xprt, timeout);
417 xprt_iter_init(&clnt->cl_xpi, xps);
418 xprt_switch_put(xps);
419
420 clnt->cl_rtt = &clnt->cl_rtt_default;
421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
422
423 atomic_set(&clnt->cl_count, 1);
424
425 if (nodename == NULL)
426 nodename = utsname()->nodename;
427 /* save the nodename */
428 rpc_clnt_set_nodename(clnt, nodename);
429
430 err = rpc_client_register(clnt, args->authflavor, args->client_name);
431 if (err)
432 goto out_no_path;
433 if (parent)
434 atomic_inc(&parent->cl_count);
435
436 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
437 return clnt;
438
439out_no_path:
440 rpc_free_iostats(clnt->cl_metrics);
441out_no_stats:
442 put_cred(clnt->cl_cred);
443 rpc_free_clid(clnt);
444out_no_clid:
445 kfree(clnt);
446out_err:
447 rpciod_down();
448out_no_rpciod:
449 xprt_switch_put(xps);
450 xprt_put(xprt);
451 trace_rpc_clnt_new_err(program->name, args->servername, err);
452 return ERR_PTR(err);
453}
454
455static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
456 struct rpc_xprt *xprt)
457{
458 struct rpc_clnt *clnt = NULL;
459 struct rpc_xprt_switch *xps;
460
461 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
462 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
463 xps = args->bc_xprt->xpt_bc_xps;
464 xprt_switch_get(xps);
465 } else {
466 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
467 if (xps == NULL) {
468 xprt_put(xprt);
469 return ERR_PTR(-ENOMEM);
470 }
471 if (xprt->bc_xprt) {
472 xprt_switch_get(xps);
473 xprt->bc_xprt->xpt_bc_xps = xps;
474 }
475 }
476 clnt = rpc_new_client(args, xps, xprt, NULL);
477 if (IS_ERR(clnt))
478 return clnt;
479
480 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
481 int err = rpc_ping(clnt);
482 if (err != 0) {
483 rpc_shutdown_client(clnt);
484 return ERR_PTR(err);
485 }
486 }
487
488 clnt->cl_softrtry = 1;
489 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
490 clnt->cl_softrtry = 0;
491 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
492 clnt->cl_softerr = 1;
493 }
494
495 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
496 clnt->cl_autobind = 1;
497 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
498 clnt->cl_noretranstimeo = 1;
499 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
500 clnt->cl_discrtry = 1;
501 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
502 clnt->cl_chatty = 1;
503
504 return clnt;
505}
506
507/**
508 * rpc_create - create an RPC client and transport with one call
509 * @args: rpc_clnt create argument structure
510 *
511 * Creates and initializes an RPC transport and an RPC client.
512 *
513 * It can ping the server in order to determine if it is up, and to see if
514 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
515 * this behavior so asynchronous tasks can also use rpc_create.
516 */
517struct rpc_clnt *rpc_create(struct rpc_create_args *args)
518{
519 struct rpc_xprt *xprt;
520 struct xprt_create xprtargs = {
521 .net = args->net,
522 .ident = args->protocol,
523 .srcaddr = args->saddress,
524 .dstaddr = args->address,
525 .addrlen = args->addrsize,
526 .servername = args->servername,
527 .bc_xprt = args->bc_xprt,
528 };
529 char servername[48];
530 struct rpc_clnt *clnt;
531 int i;
532
533 if (args->bc_xprt) {
534 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
535 xprt = args->bc_xprt->xpt_bc_xprt;
536 if (xprt) {
537 xprt_get(xprt);
538 return rpc_create_xprt(args, xprt);
539 }
540 }
541
542 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
543 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
544 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
545 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
546 /*
547 * If the caller chooses not to specify a hostname, whip
548 * up a string representation of the passed-in address.
549 */
550 if (xprtargs.servername == NULL) {
551 struct sockaddr_un *sun =
552 (struct sockaddr_un *)args->address;
553 struct sockaddr_in *sin =
554 (struct sockaddr_in *)args->address;
555 struct sockaddr_in6 *sin6 =
556 (struct sockaddr_in6 *)args->address;
557
558 servername[0] = '\0';
559 switch (args->address->sa_family) {
560 case AF_LOCAL:
561 snprintf(servername, sizeof(servername), "%s",
562 sun->sun_path);
563 break;
564 case AF_INET:
565 snprintf(servername, sizeof(servername), "%pI4",
566 &sin->sin_addr.s_addr);
567 break;
568 case AF_INET6:
569 snprintf(servername, sizeof(servername), "%pI6",
570 &sin6->sin6_addr);
571 break;
572 default:
573 /* caller wants default server name, but
574 * address family isn't recognized. */
575 return ERR_PTR(-EINVAL);
576 }
577 xprtargs.servername = servername;
578 }
579
580 xprt = xprt_create_transport(&xprtargs);
581 if (IS_ERR(xprt))
582 return (struct rpc_clnt *)xprt;
583
584 /*
585 * By default, kernel RPC client connects from a reserved port.
586 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
587 * but it is always enabled for rpciod, which handles the connect
588 * operation.
589 */
590 xprt->resvport = 1;
591 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
592 xprt->resvport = 0;
593 xprt->reuseport = 0;
594 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
595 xprt->reuseport = 1;
596
597 clnt = rpc_create_xprt(args, xprt);
598 if (IS_ERR(clnt) || args->nconnect <= 1)
599 return clnt;
600
601 for (i = 0; i < args->nconnect - 1; i++) {
602 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
603 break;
604 }
605 return clnt;
606}
607EXPORT_SYMBOL_GPL(rpc_create);
608
609/*
610 * This function clones the RPC client structure. It allows us to share the
611 * same transport while varying parameters such as the authentication
612 * flavour.
613 */
614static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
615 struct rpc_clnt *clnt)
616{
617 struct rpc_xprt_switch *xps;
618 struct rpc_xprt *xprt;
619 struct rpc_clnt *new;
620 int err;
621
622 err = -ENOMEM;
623 rcu_read_lock();
624 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
625 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
626 rcu_read_unlock();
627 if (xprt == NULL || xps == NULL) {
628 xprt_put(xprt);
629 xprt_switch_put(xps);
630 goto out_err;
631 }
632 args->servername = xprt->servername;
633 args->nodename = clnt->cl_nodename;
634
635 new = rpc_new_client(args, xps, xprt, clnt);
636 if (IS_ERR(new))
637 return new;
638
639 /* Turn off autobind on clones */
640 new->cl_autobind = 0;
641 new->cl_softrtry = clnt->cl_softrtry;
642 new->cl_softerr = clnt->cl_softerr;
643 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
644 new->cl_discrtry = clnt->cl_discrtry;
645 new->cl_chatty = clnt->cl_chatty;
646 new->cl_principal = clnt->cl_principal;
647 return new;
648
649out_err:
650 trace_rpc_clnt_clone_err(clnt, err);
651 return ERR_PTR(err);
652}
653
654/**
655 * rpc_clone_client - Clone an RPC client structure
656 *
657 * @clnt: RPC client whose parameters are copied
658 *
659 * Returns a fresh RPC client or an ERR_PTR.
660 */
661struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
662{
663 struct rpc_create_args args = {
664 .program = clnt->cl_program,
665 .prognumber = clnt->cl_prog,
666 .version = clnt->cl_vers,
667 .authflavor = clnt->cl_auth->au_flavor,
668 .cred = clnt->cl_cred,
669 };
670 return __rpc_clone_client(&args, clnt);
671}
672EXPORT_SYMBOL_GPL(rpc_clone_client);
673
674/**
675 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
676 *
677 * @clnt: RPC client whose parameters are copied
678 * @flavor: security flavor for new client
679 *
680 * Returns a fresh RPC client or an ERR_PTR.
681 */
682struct rpc_clnt *
683rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
684{
685 struct rpc_create_args args = {
686 .program = clnt->cl_program,
687 .prognumber = clnt->cl_prog,
688 .version = clnt->cl_vers,
689 .authflavor = flavor,
690 .cred = clnt->cl_cred,
691 };
692 return __rpc_clone_client(&args, clnt);
693}
694EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
695
696/**
697 * rpc_switch_client_transport: switch the RPC transport on the fly
698 * @clnt: pointer to a struct rpc_clnt
699 * @args: pointer to the new transport arguments
700 * @timeout: pointer to the new timeout parameters
701 *
702 * This function allows the caller to switch the RPC transport for the
703 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
704 * server, for instance. It assumes that the caller has ensured that
705 * there are no active RPC tasks by using some form of locking.
706 *
707 * Returns zero if "clnt" is now using the new xprt. Otherwise a
708 * negative errno is returned, and "clnt" continues to use the old
709 * xprt.
710 */
711int rpc_switch_client_transport(struct rpc_clnt *clnt,
712 struct xprt_create *args,
713 const struct rpc_timeout *timeout)
714{
715 const struct rpc_timeout *old_timeo;
716 rpc_authflavor_t pseudoflavor;
717 struct rpc_xprt_switch *xps, *oldxps;
718 struct rpc_xprt *xprt, *old;
719 struct rpc_clnt *parent;
720 int err;
721
722 xprt = xprt_create_transport(args);
723 if (IS_ERR(xprt))
724 return PTR_ERR(xprt);
725
726 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
727 if (xps == NULL) {
728 xprt_put(xprt);
729 return -ENOMEM;
730 }
731
732 pseudoflavor = clnt->cl_auth->au_flavor;
733
734 old_timeo = clnt->cl_timeout;
735 old = rpc_clnt_set_transport(clnt, xprt, timeout);
736 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
737
738 rpc_unregister_client(clnt);
739 __rpc_clnt_remove_pipedir(clnt);
740 rpc_clnt_debugfs_unregister(clnt);
741
742 /*
743 * A new transport was created. "clnt" therefore
744 * becomes the root of a new cl_parent tree. clnt's
745 * children, if it has any, still point to the old xprt.
746 */
747 parent = clnt->cl_parent;
748 clnt->cl_parent = clnt;
749
750 /*
751 * The old rpc_auth cache cannot be re-used. GSS
752 * contexts in particular are between a single
753 * client and server.
754 */
755 err = rpc_client_register(clnt, pseudoflavor, NULL);
756 if (err)
757 goto out_revert;
758
759 synchronize_rcu();
760 if (parent != clnt)
761 rpc_release_client(parent);
762 xprt_switch_put(oldxps);
763 xprt_put(old);
764 trace_rpc_clnt_replace_xprt(clnt);
765 return 0;
766
767out_revert:
768 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
769 rpc_clnt_set_transport(clnt, old, old_timeo);
770 clnt->cl_parent = parent;
771 rpc_client_register(clnt, pseudoflavor, NULL);
772 xprt_switch_put(xps);
773 xprt_put(xprt);
774 trace_rpc_clnt_replace_xprt_err(clnt);
775 return err;
776}
777EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
778
779static
780int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
781{
782 struct rpc_xprt_switch *xps;
783
784 rcu_read_lock();
785 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
786 rcu_read_unlock();
787 if (xps == NULL)
788 return -EAGAIN;
789 xprt_iter_init_listall(xpi, xps);
790 xprt_switch_put(xps);
791 return 0;
792}
793
794/**
795 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
796 * @clnt: pointer to client
797 * @fn: function to apply
798 * @data: void pointer to function data
799 *
800 * Iterates through the list of RPC transports currently attached to the
801 * client and applies the function fn(clnt, xprt, data).
802 *
803 * On error, the iteration stops, and the function returns the error value.
804 */
805int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
806 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
807 void *data)
808{
809 struct rpc_xprt_iter xpi;
810 int ret;
811
812 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
813 if (ret)
814 return ret;
815 for (;;) {
816 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
817
818 if (!xprt)
819 break;
820 ret = fn(clnt, xprt, data);
821 xprt_put(xprt);
822 if (ret < 0)
823 break;
824 }
825 xprt_iter_destroy(&xpi);
826 return ret;
827}
828EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
829
830/*
831 * Kill all tasks for the given client.
832 * XXX: kill their descendants as well?
833 */
834void rpc_killall_tasks(struct rpc_clnt *clnt)
835{
836 struct rpc_task *rovr;
837
838
839 if (list_empty(&clnt->cl_tasks))
840 return;
841
842 /*
843 * Spin lock all_tasks to prevent changes...
844 */
845 trace_rpc_clnt_killall(clnt);
846 spin_lock(&clnt->cl_lock);
847 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
848 rpc_signal_task(rovr);
849 spin_unlock(&clnt->cl_lock);
850}
851EXPORT_SYMBOL_GPL(rpc_killall_tasks);
852
853/*
854 * Properly shut down an RPC client, terminating all outstanding
855 * requests.
856 */
857void rpc_shutdown_client(struct rpc_clnt *clnt)
858{
859 might_sleep();
860
861 trace_rpc_clnt_shutdown(clnt);
862
863 while (!list_empty(&clnt->cl_tasks)) {
864 rpc_killall_tasks(clnt);
865 wait_event_timeout(destroy_wait,
866 list_empty(&clnt->cl_tasks), 1*HZ);
867 }
868
869 rpc_release_client(clnt);
870}
871EXPORT_SYMBOL_GPL(rpc_shutdown_client);
872
873/*
874 * Free an RPC client
875 */
876static void rpc_free_client_work(struct work_struct *work)
877{
878 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
879
880 trace_rpc_clnt_free(clnt);
881
882 /* These might block on processes that might allocate memory,
883 * so they cannot be called in rpciod, so they are handled separately
884 * here.
885 */
886 rpc_clnt_debugfs_unregister(clnt);
887 rpc_free_clid(clnt);
888 rpc_clnt_remove_pipedir(clnt);
889 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
890
891 kfree(clnt);
892 rpciod_down();
893}
894static struct rpc_clnt *
895rpc_free_client(struct rpc_clnt *clnt)
896{
897 struct rpc_clnt *parent = NULL;
898
899 trace_rpc_clnt_release(clnt);
900 if (clnt->cl_parent != clnt)
901 parent = clnt->cl_parent;
902 rpc_unregister_client(clnt);
903 rpc_free_iostats(clnt->cl_metrics);
904 clnt->cl_metrics = NULL;
905 xprt_iter_destroy(&clnt->cl_xpi);
906 put_cred(clnt->cl_cred);
907
908 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
909 schedule_work(&clnt->cl_work);
910 return parent;
911}
912
913/*
914 * Free an RPC client
915 */
916static struct rpc_clnt *
917rpc_free_auth(struct rpc_clnt *clnt)
918{
919 if (clnt->cl_auth == NULL)
920 return rpc_free_client(clnt);
921
922 /*
923 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
924 * release remaining GSS contexts. This mechanism ensures
925 * that it can do so safely.
926 */
927 atomic_inc(&clnt->cl_count);
928 rpcauth_release(clnt->cl_auth);
929 clnt->cl_auth = NULL;
930 if (atomic_dec_and_test(&clnt->cl_count))
931 return rpc_free_client(clnt);
932 return NULL;
933}
934
935/*
936 * Release reference to the RPC client
937 */
938void
939rpc_release_client(struct rpc_clnt *clnt)
940{
941 do {
942 if (list_empty(&clnt->cl_tasks))
943 wake_up(&destroy_wait);
944 if (!atomic_dec_and_test(&clnt->cl_count))
945 break;
946 clnt = rpc_free_auth(clnt);
947 } while (clnt != NULL);
948}
949EXPORT_SYMBOL_GPL(rpc_release_client);
950
951/**
952 * rpc_bind_new_program - bind a new RPC program to an existing client
953 * @old: old rpc_client
954 * @program: rpc program to set
955 * @vers: rpc program version
956 *
957 * Clones the rpc client and sets up a new RPC program. This is mainly
958 * of use for enabling different RPC programs to share the same transport.
959 * The Sun NFSv2/v3 ACL protocol can do this.
960 */
961struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
962 const struct rpc_program *program,
963 u32 vers)
964{
965 struct rpc_create_args args = {
966 .program = program,
967 .prognumber = program->number,
968 .version = vers,
969 .authflavor = old->cl_auth->au_flavor,
970 .cred = old->cl_cred,
971 };
972 struct rpc_clnt *clnt;
973 int err;
974
975 clnt = __rpc_clone_client(&args, old);
976 if (IS_ERR(clnt))
977 goto out;
978 err = rpc_ping(clnt);
979 if (err != 0) {
980 rpc_shutdown_client(clnt);
981 clnt = ERR_PTR(err);
982 }
983out:
984 return clnt;
985}
986EXPORT_SYMBOL_GPL(rpc_bind_new_program);
987
988struct rpc_xprt *
989rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
990{
991 struct rpc_xprt_switch *xps;
992
993 if (!xprt)
994 return NULL;
995 rcu_read_lock();
996 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
997 atomic_long_inc(&xps->xps_queuelen);
998 rcu_read_unlock();
999 atomic_long_inc(&xprt->queuelen);
1000
1001 return xprt;
1002}
1003
1004static void
1005rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1006{
1007 struct rpc_xprt_switch *xps;
1008
1009 atomic_long_dec(&xprt->queuelen);
1010 rcu_read_lock();
1011 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1012 atomic_long_dec(&xps->xps_queuelen);
1013 rcu_read_unlock();
1014
1015 xprt_put(xprt);
1016}
1017
1018void rpc_task_release_transport(struct rpc_task *task)
1019{
1020 struct rpc_xprt *xprt = task->tk_xprt;
1021
1022 if (xprt) {
1023 task->tk_xprt = NULL;
1024 if (task->tk_client)
1025 rpc_task_release_xprt(task->tk_client, xprt);
1026 else
1027 xprt_put(xprt);
1028 }
1029}
1030EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1031
1032void rpc_task_release_client(struct rpc_task *task)
1033{
1034 struct rpc_clnt *clnt = task->tk_client;
1035
1036 rpc_task_release_transport(task);
1037 if (clnt != NULL) {
1038 /* Remove from client task list */
1039 spin_lock(&clnt->cl_lock);
1040 list_del(&task->tk_task);
1041 spin_unlock(&clnt->cl_lock);
1042 task->tk_client = NULL;
1043
1044 rpc_release_client(clnt);
1045 }
1046}
1047
1048static struct rpc_xprt *
1049rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1050{
1051 struct rpc_xprt *xprt;
1052
1053 rcu_read_lock();
1054 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1055 rcu_read_unlock();
1056 return rpc_task_get_xprt(clnt, xprt);
1057}
1058
1059static struct rpc_xprt *
1060rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1061{
1062 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1063}
1064
1065static
1066void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1067{
1068 if (task->tk_xprt)
1069 return;
1070 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1071 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1072 else
1073 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1074}
1075
1076static
1077void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1078{
1079
1080 if (clnt != NULL) {
1081 rpc_task_set_transport(task, clnt);
1082 task->tk_client = clnt;
1083 atomic_inc(&clnt->cl_count);
1084 if (clnt->cl_softrtry)
1085 task->tk_flags |= RPC_TASK_SOFT;
1086 if (clnt->cl_softerr)
1087 task->tk_flags |= RPC_TASK_TIMEOUT;
1088 if (clnt->cl_noretranstimeo)
1089 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1090 if (atomic_read(&clnt->cl_swapper))
1091 task->tk_flags |= RPC_TASK_SWAPPER;
1092 /* Add to the client's list of all tasks */
1093 spin_lock(&clnt->cl_lock);
1094 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1095 spin_unlock(&clnt->cl_lock);
1096 }
1097}
1098
1099static void
1100rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1101{
1102 if (msg != NULL) {
1103 task->tk_msg.rpc_proc = msg->rpc_proc;
1104 task->tk_msg.rpc_argp = msg->rpc_argp;
1105 task->tk_msg.rpc_resp = msg->rpc_resp;
1106 task->tk_msg.rpc_cred = msg->rpc_cred;
1107 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1108 get_cred(task->tk_msg.rpc_cred);
1109 }
1110}
1111
1112/*
1113 * Default callback for async RPC calls
1114 */
1115static void
1116rpc_default_callback(struct rpc_task *task, void *data)
1117{
1118}
1119
1120static const struct rpc_call_ops rpc_default_ops = {
1121 .rpc_call_done = rpc_default_callback,
1122};
1123
1124/**
1125 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1126 * @task_setup_data: pointer to task initialisation data
1127 */
1128struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1129{
1130 struct rpc_task *task;
1131
1132 task = rpc_new_task(task_setup_data);
1133
1134 if (!RPC_IS_ASYNC(task))
1135 task->tk_flags |= RPC_TASK_CRED_NOREF;
1136
1137 rpc_task_set_client(task, task_setup_data->rpc_client);
1138 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1139
1140 if (task->tk_action == NULL)
1141 rpc_call_start(task);
1142
1143 atomic_inc(&task->tk_count);
1144 rpc_execute(task);
1145 return task;
1146}
1147EXPORT_SYMBOL_GPL(rpc_run_task);
1148
1149/**
1150 * rpc_call_sync - Perform a synchronous RPC call
1151 * @clnt: pointer to RPC client
1152 * @msg: RPC call parameters
1153 * @flags: RPC call flags
1154 */
1155int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1156{
1157 struct rpc_task *task;
1158 struct rpc_task_setup task_setup_data = {
1159 .rpc_client = clnt,
1160 .rpc_message = msg,
1161 .callback_ops = &rpc_default_ops,
1162 .flags = flags,
1163 };
1164 int status;
1165
1166 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1167 if (flags & RPC_TASK_ASYNC) {
1168 rpc_release_calldata(task_setup_data.callback_ops,
1169 task_setup_data.callback_data);
1170 return -EINVAL;
1171 }
1172
1173 task = rpc_run_task(&task_setup_data);
1174 if (IS_ERR(task))
1175 return PTR_ERR(task);
1176 status = task->tk_status;
1177 rpc_put_task(task);
1178 return status;
1179}
1180EXPORT_SYMBOL_GPL(rpc_call_sync);
1181
1182/**
1183 * rpc_call_async - Perform an asynchronous RPC call
1184 * @clnt: pointer to RPC client
1185 * @msg: RPC call parameters
1186 * @flags: RPC call flags
1187 * @tk_ops: RPC call ops
1188 * @data: user call data
1189 */
1190int
1191rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1192 const struct rpc_call_ops *tk_ops, void *data)
1193{
1194 struct rpc_task *task;
1195 struct rpc_task_setup task_setup_data = {
1196 .rpc_client = clnt,
1197 .rpc_message = msg,
1198 .callback_ops = tk_ops,
1199 .callback_data = data,
1200 .flags = flags|RPC_TASK_ASYNC,
1201 };
1202
1203 task = rpc_run_task(&task_setup_data);
1204 if (IS_ERR(task))
1205 return PTR_ERR(task);
1206 rpc_put_task(task);
1207 return 0;
1208}
1209EXPORT_SYMBOL_GPL(rpc_call_async);
1210
1211#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1212static void call_bc_encode(struct rpc_task *task);
1213
1214/**
1215 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1216 * rpc_execute against it
1217 * @req: RPC request
1218 */
1219struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1220{
1221 struct rpc_task *task;
1222 struct rpc_task_setup task_setup_data = {
1223 .callback_ops = &rpc_default_ops,
1224 .flags = RPC_TASK_SOFTCONN |
1225 RPC_TASK_NO_RETRANS_TIMEOUT,
1226 };
1227
1228 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1229 /*
1230 * Create an rpc_task to send the data
1231 */
1232 task = rpc_new_task(&task_setup_data);
1233 xprt_init_bc_request(req, task);
1234
1235 task->tk_action = call_bc_encode;
1236 atomic_inc(&task->tk_count);
1237 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1238 rpc_execute(task);
1239
1240 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1241 return task;
1242}
1243#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1244
1245/**
1246 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1247 * @req: RPC request to prepare
1248 * @pages: vector of struct page pointers
1249 * @base: offset in first page where receive should start, in bytes
1250 * @len: expected size of the upper layer data payload, in bytes
1251 * @hdrsize: expected size of upper layer reply header, in XDR words
1252 *
1253 */
1254void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1255 unsigned int base, unsigned int len,
1256 unsigned int hdrsize)
1257{
1258 /* Subtract one to force an extra word of buffer space for the
1259 * payload's XDR pad to fall into the rcv_buf's tail iovec.
1260 */
1261 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1;
1262
1263 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1264 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1265}
1266EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1267
1268void
1269rpc_call_start(struct rpc_task *task)
1270{
1271 task->tk_action = call_start;
1272}
1273EXPORT_SYMBOL_GPL(rpc_call_start);
1274
1275/**
1276 * rpc_peeraddr - extract remote peer address from clnt's xprt
1277 * @clnt: RPC client structure
1278 * @buf: target buffer
1279 * @bufsize: length of target buffer
1280 *
1281 * Returns the number of bytes that are actually in the stored address.
1282 */
1283size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1284{
1285 size_t bytes;
1286 struct rpc_xprt *xprt;
1287
1288 rcu_read_lock();
1289 xprt = rcu_dereference(clnt->cl_xprt);
1290
1291 bytes = xprt->addrlen;
1292 if (bytes > bufsize)
1293 bytes = bufsize;
1294 memcpy(buf, &xprt->addr, bytes);
1295 rcu_read_unlock();
1296
1297 return bytes;
1298}
1299EXPORT_SYMBOL_GPL(rpc_peeraddr);
1300
1301/**
1302 * rpc_peeraddr2str - return remote peer address in printable format
1303 * @clnt: RPC client structure
1304 * @format: address format
1305 *
1306 * NB: the lifetime of the memory referenced by the returned pointer is
1307 * the same as the rpc_xprt itself. As long as the caller uses this
1308 * pointer, it must hold the RCU read lock.
1309 */
1310const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1311 enum rpc_display_format_t format)
1312{
1313 struct rpc_xprt *xprt;
1314
1315 xprt = rcu_dereference(clnt->cl_xprt);
1316
1317 if (xprt->address_strings[format] != NULL)
1318 return xprt->address_strings[format];
1319 else
1320 return "unprintable";
1321}
1322EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1323
1324static const struct sockaddr_in rpc_inaddr_loopback = {
1325 .sin_family = AF_INET,
1326 .sin_addr.s_addr = htonl(INADDR_ANY),
1327};
1328
1329static const struct sockaddr_in6 rpc_in6addr_loopback = {
1330 .sin6_family = AF_INET6,
1331 .sin6_addr = IN6ADDR_ANY_INIT,
1332};
1333
1334/*
1335 * Try a getsockname() on a connected datagram socket. Using a
1336 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1337 * This conserves the ephemeral port number space.
1338 *
1339 * Returns zero and fills in "buf" if successful; otherwise, a
1340 * negative errno is returned.
1341 */
1342static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1343 struct sockaddr *buf)
1344{
1345 struct socket *sock;
1346 int err;
1347
1348 err = __sock_create(net, sap->sa_family,
1349 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1350 if (err < 0) {
1351 dprintk("RPC: can't create UDP socket (%d)\n", err);
1352 goto out;
1353 }
1354
1355 switch (sap->sa_family) {
1356 case AF_INET:
1357 err = kernel_bind(sock,
1358 (struct sockaddr *)&rpc_inaddr_loopback,
1359 sizeof(rpc_inaddr_loopback));
1360 break;
1361 case AF_INET6:
1362 err = kernel_bind(sock,
1363 (struct sockaddr *)&rpc_in6addr_loopback,
1364 sizeof(rpc_in6addr_loopback));
1365 break;
1366 default:
1367 err = -EAFNOSUPPORT;
1368 goto out;
1369 }
1370 if (err < 0) {
1371 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1372 goto out_release;
1373 }
1374
1375 err = kernel_connect(sock, sap, salen, 0);
1376 if (err < 0) {
1377 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1378 goto out_release;
1379 }
1380
1381 err = kernel_getsockname(sock, buf);
1382 if (err < 0) {
1383 dprintk("RPC: getsockname failed (%d)\n", err);
1384 goto out_release;
1385 }
1386
1387 err = 0;
1388 if (buf->sa_family == AF_INET6) {
1389 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1390 sin6->sin6_scope_id = 0;
1391 }
1392 dprintk("RPC: %s succeeded\n", __func__);
1393
1394out_release:
1395 sock_release(sock);
1396out:
1397 return err;
1398}
1399
1400/*
1401 * Scraping a connected socket failed, so we don't have a useable
1402 * local address. Fallback: generate an address that will prevent
1403 * the server from calling us back.
1404 *
1405 * Returns zero and fills in "buf" if successful; otherwise, a
1406 * negative errno is returned.
1407 */
1408static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1409{
1410 switch (family) {
1411 case AF_INET:
1412 if (buflen < sizeof(rpc_inaddr_loopback))
1413 return -EINVAL;
1414 memcpy(buf, &rpc_inaddr_loopback,
1415 sizeof(rpc_inaddr_loopback));
1416 break;
1417 case AF_INET6:
1418 if (buflen < sizeof(rpc_in6addr_loopback))
1419 return -EINVAL;
1420 memcpy(buf, &rpc_in6addr_loopback,
1421 sizeof(rpc_in6addr_loopback));
1422 break;
1423 default:
1424 dprintk("RPC: %s: address family not supported\n",
1425 __func__);
1426 return -EAFNOSUPPORT;
1427 }
1428 dprintk("RPC: %s: succeeded\n", __func__);
1429 return 0;
1430}
1431
1432/**
1433 * rpc_localaddr - discover local endpoint address for an RPC client
1434 * @clnt: RPC client structure
1435 * @buf: target buffer
1436 * @buflen: size of target buffer, in bytes
1437 *
1438 * Returns zero and fills in "buf" and "buflen" if successful;
1439 * otherwise, a negative errno is returned.
1440 *
1441 * This works even if the underlying transport is not currently connected,
1442 * or if the upper layer never previously provided a source address.
1443 *
1444 * The result of this function call is transient: multiple calls in
1445 * succession may give different results, depending on how local
1446 * networking configuration changes over time.
1447 */
1448int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1449{
1450 struct sockaddr_storage address;
1451 struct sockaddr *sap = (struct sockaddr *)&address;
1452 struct rpc_xprt *xprt;
1453 struct net *net;
1454 size_t salen;
1455 int err;
1456
1457 rcu_read_lock();
1458 xprt = rcu_dereference(clnt->cl_xprt);
1459 salen = xprt->addrlen;
1460 memcpy(sap, &xprt->addr, salen);
1461 net = get_net(xprt->xprt_net);
1462 rcu_read_unlock();
1463
1464 rpc_set_port(sap, 0);
1465 err = rpc_sockname(net, sap, salen, buf);
1466 put_net(net);
1467 if (err != 0)
1468 /* Couldn't discover local address, return ANYADDR */
1469 return rpc_anyaddr(sap->sa_family, buf, buflen);
1470 return 0;
1471}
1472EXPORT_SYMBOL_GPL(rpc_localaddr);
1473
1474void
1475rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1476{
1477 struct rpc_xprt *xprt;
1478
1479 rcu_read_lock();
1480 xprt = rcu_dereference(clnt->cl_xprt);
1481 if (xprt->ops->set_buffer_size)
1482 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1483 rcu_read_unlock();
1484}
1485EXPORT_SYMBOL_GPL(rpc_setbufsize);
1486
1487/**
1488 * rpc_net_ns - Get the network namespace for this RPC client
1489 * @clnt: RPC client to query
1490 *
1491 */
1492struct net *rpc_net_ns(struct rpc_clnt *clnt)
1493{
1494 struct net *ret;
1495
1496 rcu_read_lock();
1497 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1498 rcu_read_unlock();
1499 return ret;
1500}
1501EXPORT_SYMBOL_GPL(rpc_net_ns);
1502
1503/**
1504 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1505 * @clnt: RPC client to query
1506 *
1507 * For stream transports, this is one RPC record fragment (see RFC
1508 * 1831), as we don't support multi-record requests yet. For datagram
1509 * transports, this is the size of an IP packet minus the IP, UDP, and
1510 * RPC header sizes.
1511 */
1512size_t rpc_max_payload(struct rpc_clnt *clnt)
1513{
1514 size_t ret;
1515
1516 rcu_read_lock();
1517 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1518 rcu_read_unlock();
1519 return ret;
1520}
1521EXPORT_SYMBOL_GPL(rpc_max_payload);
1522
1523/**
1524 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1525 * @clnt: RPC client to query
1526 */
1527size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1528{
1529 struct rpc_xprt *xprt;
1530 size_t ret;
1531
1532 rcu_read_lock();
1533 xprt = rcu_dereference(clnt->cl_xprt);
1534 ret = xprt->ops->bc_maxpayload(xprt);
1535 rcu_read_unlock();
1536 return ret;
1537}
1538EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1539
1540unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1541{
1542 struct rpc_xprt *xprt;
1543 unsigned int ret;
1544
1545 rcu_read_lock();
1546 xprt = rcu_dereference(clnt->cl_xprt);
1547 ret = xprt->ops->bc_num_slots(xprt);
1548 rcu_read_unlock();
1549 return ret;
1550}
1551EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1552
1553/**
1554 * rpc_force_rebind - force transport to check that remote port is unchanged
1555 * @clnt: client to rebind
1556 *
1557 */
1558void rpc_force_rebind(struct rpc_clnt *clnt)
1559{
1560 if (clnt->cl_autobind) {
1561 rcu_read_lock();
1562 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1563 rcu_read_unlock();
1564 }
1565}
1566EXPORT_SYMBOL_GPL(rpc_force_rebind);
1567
1568static int
1569__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1570{
1571 task->tk_status = 0;
1572 task->tk_rpc_status = 0;
1573 task->tk_action = action;
1574 return 1;
1575}
1576
1577/*
1578 * Restart an (async) RPC call. Usually called from within the
1579 * exit handler.
1580 */
1581int
1582rpc_restart_call(struct rpc_task *task)
1583{
1584 return __rpc_restart_call(task, call_start);
1585}
1586EXPORT_SYMBOL_GPL(rpc_restart_call);
1587
1588/*
1589 * Restart an (async) RPC call from the call_prepare state.
1590 * Usually called from within the exit handler.
1591 */
1592int
1593rpc_restart_call_prepare(struct rpc_task *task)
1594{
1595 if (task->tk_ops->rpc_call_prepare != NULL)
1596 return __rpc_restart_call(task, rpc_prepare_task);
1597 return rpc_restart_call(task);
1598}
1599EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1600
1601const char
1602*rpc_proc_name(const struct rpc_task *task)
1603{
1604 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1605
1606 if (proc) {
1607 if (proc->p_name)
1608 return proc->p_name;
1609 else
1610 return "NULL";
1611 } else
1612 return "no proc";
1613}
1614
1615static void
1616__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1617{
1618 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1619 task->tk_rpc_status = rpc_status;
1620 rpc_exit(task, tk_status);
1621}
1622
1623static void
1624rpc_call_rpcerror(struct rpc_task *task, int status)
1625{
1626 __rpc_call_rpcerror(task, status, status);
1627}
1628
1629/*
1630 * 0. Initial state
1631 *
1632 * Other FSM states can be visited zero or more times, but
1633 * this state is visited exactly once for each RPC.
1634 */
1635static void
1636call_start(struct rpc_task *task)
1637{
1638 struct rpc_clnt *clnt = task->tk_client;
1639 int idx = task->tk_msg.rpc_proc->p_statidx;
1640
1641 trace_rpc_request(task);
1642 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1643 clnt->cl_program->name, clnt->cl_vers,
1644 rpc_proc_name(task),
1645 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1646
1647 /* Increment call count (version might not be valid for ping) */
1648 if (clnt->cl_program->version[clnt->cl_vers])
1649 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1650 clnt->cl_stats->rpccnt++;
1651 task->tk_action = call_reserve;
1652 rpc_task_set_transport(task, clnt);
1653}
1654
1655/*
1656 * 1. Reserve an RPC call slot
1657 */
1658static void
1659call_reserve(struct rpc_task *task)
1660{
1661 dprint_status(task);
1662
1663 task->tk_status = 0;
1664 task->tk_action = call_reserveresult;
1665 xprt_reserve(task);
1666}
1667
1668static void call_retry_reserve(struct rpc_task *task);
1669
1670/*
1671 * 1b. Grok the result of xprt_reserve()
1672 */
1673static void
1674call_reserveresult(struct rpc_task *task)
1675{
1676 int status = task->tk_status;
1677
1678 dprint_status(task);
1679
1680 /*
1681 * After a call to xprt_reserve(), we must have either
1682 * a request slot or else an error status.
1683 */
1684 task->tk_status = 0;
1685 if (status >= 0) {
1686 if (task->tk_rqstp) {
1687 task->tk_action = call_refresh;
1688 return;
1689 }
1690
1691 rpc_call_rpcerror(task, -EIO);
1692 return;
1693 }
1694
1695 /*
1696 * Even though there was an error, we may have acquired
1697 * a request slot somehow. Make sure not to leak it.
1698 */
1699 if (task->tk_rqstp)
1700 xprt_release(task);
1701
1702 switch (status) {
1703 case -ENOMEM:
1704 rpc_delay(task, HZ >> 2);
1705 fallthrough;
1706 case -EAGAIN: /* woken up; retry */
1707 task->tk_action = call_retry_reserve;
1708 return;
1709 default:
1710 rpc_call_rpcerror(task, status);
1711 }
1712}
1713
1714/*
1715 * 1c. Retry reserving an RPC call slot
1716 */
1717static void
1718call_retry_reserve(struct rpc_task *task)
1719{
1720 dprint_status(task);
1721
1722 task->tk_status = 0;
1723 task->tk_action = call_reserveresult;
1724 xprt_retry_reserve(task);
1725}
1726
1727/*
1728 * 2. Bind and/or refresh the credentials
1729 */
1730static void
1731call_refresh(struct rpc_task *task)
1732{
1733 dprint_status(task);
1734
1735 task->tk_action = call_refreshresult;
1736 task->tk_status = 0;
1737 task->tk_client->cl_stats->rpcauthrefresh++;
1738 rpcauth_refreshcred(task);
1739}
1740
1741/*
1742 * 2a. Process the results of a credential refresh
1743 */
1744static void
1745call_refreshresult(struct rpc_task *task)
1746{
1747 int status = task->tk_status;
1748
1749 dprint_status(task);
1750
1751 task->tk_status = 0;
1752 task->tk_action = call_refresh;
1753 switch (status) {
1754 case 0:
1755 if (rpcauth_uptodatecred(task)) {
1756 task->tk_action = call_allocate;
1757 return;
1758 }
1759 /* Use rate-limiting and a max number of retries if refresh
1760 * had status 0 but failed to update the cred.
1761 */
1762 fallthrough;
1763 case -ETIMEDOUT:
1764 rpc_delay(task, 3*HZ);
1765 fallthrough;
1766 case -EAGAIN:
1767 status = -EACCES;
1768 fallthrough;
1769 case -EKEYEXPIRED:
1770 if (!task->tk_cred_retry)
1771 break;
1772 task->tk_cred_retry--;
1773 dprintk("RPC: %5u %s: retry refresh creds\n",
1774 task->tk_pid, __func__);
1775 return;
1776 }
1777 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1778 task->tk_pid, __func__, status);
1779 rpc_call_rpcerror(task, status);
1780}
1781
1782/*
1783 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1784 * (Note: buffer memory is freed in xprt_release).
1785 */
1786static void
1787call_allocate(struct rpc_task *task)
1788{
1789 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1790 struct rpc_rqst *req = task->tk_rqstp;
1791 struct rpc_xprt *xprt = req->rq_xprt;
1792 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1793 int status;
1794
1795 dprint_status(task);
1796
1797 task->tk_status = 0;
1798 task->tk_action = call_encode;
1799
1800 if (req->rq_buffer)
1801 return;
1802
1803 if (proc->p_proc != 0) {
1804 BUG_ON(proc->p_arglen == 0);
1805 if (proc->p_decode != NULL)
1806 BUG_ON(proc->p_replen == 0);
1807 }
1808
1809 /*
1810 * Calculate the size (in quads) of the RPC call
1811 * and reply headers, and convert both values
1812 * to byte sizes.
1813 */
1814 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1815 proc->p_arglen;
1816 req->rq_callsize <<= 2;
1817 /*
1818 * Note: the reply buffer must at minimum allocate enough space
1819 * for the 'struct accepted_reply' from RFC5531.
1820 */
1821 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1822 max_t(size_t, proc->p_replen, 2);
1823 req->rq_rcvsize <<= 2;
1824
1825 status = xprt->ops->buf_alloc(task);
1826 xprt_inject_disconnect(xprt);
1827 if (status == 0)
1828 return;
1829 if (status != -ENOMEM) {
1830 rpc_call_rpcerror(task, status);
1831 return;
1832 }
1833
1834 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1835
1836 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1837 task->tk_action = call_allocate;
1838 rpc_delay(task, HZ>>4);
1839 return;
1840 }
1841
1842 rpc_call_rpcerror(task, -ERESTARTSYS);
1843}
1844
1845static int
1846rpc_task_need_encode(struct rpc_task *task)
1847{
1848 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1849 (!(task->tk_flags & RPC_TASK_SENT) ||
1850 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1851 xprt_request_need_retransmit(task));
1852}
1853
1854static void
1855rpc_xdr_encode(struct rpc_task *task)
1856{
1857 struct rpc_rqst *req = task->tk_rqstp;
1858 struct xdr_stream xdr;
1859
1860 xdr_buf_init(&req->rq_snd_buf,
1861 req->rq_buffer,
1862 req->rq_callsize);
1863 xdr_buf_init(&req->rq_rcv_buf,
1864 req->rq_rbuffer,
1865 req->rq_rcvsize);
1866
1867 req->rq_reply_bytes_recvd = 0;
1868 req->rq_snd_buf.head[0].iov_len = 0;
1869 xdr_init_encode(&xdr, &req->rq_snd_buf,
1870 req->rq_snd_buf.head[0].iov_base, req);
1871 xdr_free_bvec(&req->rq_snd_buf);
1872 if (rpc_encode_header(task, &xdr))
1873 return;
1874
1875 task->tk_status = rpcauth_wrap_req(task, &xdr);
1876}
1877
1878/*
1879 * 3. Encode arguments of an RPC call
1880 */
1881static void
1882call_encode(struct rpc_task *task)
1883{
1884 if (!rpc_task_need_encode(task))
1885 goto out;
1886 dprint_status(task);
1887 /* Dequeue task from the receive queue while we're encoding */
1888 xprt_request_dequeue_xprt(task);
1889 /* Encode here so that rpcsec_gss can use correct sequence number. */
1890 rpc_xdr_encode(task);
1891 /* Did the encode result in an error condition? */
1892 if (task->tk_status != 0) {
1893 /* Was the error nonfatal? */
1894 switch (task->tk_status) {
1895 case -EAGAIN:
1896 case -ENOMEM:
1897 rpc_delay(task, HZ >> 4);
1898 break;
1899 case -EKEYEXPIRED:
1900 if (!task->tk_cred_retry) {
1901 rpc_exit(task, task->tk_status);
1902 } else {
1903 task->tk_action = call_refresh;
1904 task->tk_cred_retry--;
1905 dprintk("RPC: %5u %s: retry refresh creds\n",
1906 task->tk_pid, __func__);
1907 }
1908 break;
1909 default:
1910 rpc_call_rpcerror(task, task->tk_status);
1911 }
1912 return;
1913 }
1914
1915 /* Add task to reply queue before transmission to avoid races */
1916 if (rpc_reply_expected(task))
1917 xprt_request_enqueue_receive(task);
1918 xprt_request_enqueue_transmit(task);
1919out:
1920 task->tk_action = call_transmit;
1921 /* Check that the connection is OK */
1922 if (!xprt_bound(task->tk_xprt))
1923 task->tk_action = call_bind;
1924 else if (!xprt_connected(task->tk_xprt))
1925 task->tk_action = call_connect;
1926}
1927
1928/*
1929 * Helpers to check if the task was already transmitted, and
1930 * to take action when that is the case.
1931 */
1932static bool
1933rpc_task_transmitted(struct rpc_task *task)
1934{
1935 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1936}
1937
1938static void
1939rpc_task_handle_transmitted(struct rpc_task *task)
1940{
1941 xprt_end_transmit(task);
1942 task->tk_action = call_transmit_status;
1943}
1944
1945/*
1946 * 4. Get the server port number if not yet set
1947 */
1948static void
1949call_bind(struct rpc_task *task)
1950{
1951 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1952
1953 if (rpc_task_transmitted(task)) {
1954 rpc_task_handle_transmitted(task);
1955 return;
1956 }
1957
1958 if (xprt_bound(xprt)) {
1959 task->tk_action = call_connect;
1960 return;
1961 }
1962
1963 dprint_status(task);
1964
1965 task->tk_action = call_bind_status;
1966 if (!xprt_prepare_transmit(task))
1967 return;
1968
1969 xprt->ops->rpcbind(task);
1970}
1971
1972/*
1973 * 4a. Sort out bind result
1974 */
1975static void
1976call_bind_status(struct rpc_task *task)
1977{
1978 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1979 int status = -EIO;
1980
1981 if (rpc_task_transmitted(task)) {
1982 rpc_task_handle_transmitted(task);
1983 return;
1984 }
1985
1986 dprint_status(task);
1987 trace_rpc_bind_status(task);
1988 if (task->tk_status >= 0)
1989 goto out_next;
1990 if (xprt_bound(xprt)) {
1991 task->tk_status = 0;
1992 goto out_next;
1993 }
1994
1995 switch (task->tk_status) {
1996 case -ENOMEM:
1997 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1998 rpc_delay(task, HZ >> 2);
1999 goto retry_timeout;
2000 case -EACCES:
2001 dprintk("RPC: %5u remote rpcbind: RPC program/version "
2002 "unavailable\n", task->tk_pid);
2003 /* fail immediately if this is an RPC ping */
2004 if (task->tk_msg.rpc_proc->p_proc == 0) {
2005 status = -EOPNOTSUPP;
2006 break;
2007 }
2008 if (task->tk_rebind_retry == 0)
2009 break;
2010 task->tk_rebind_retry--;
2011 rpc_delay(task, 3*HZ);
2012 goto retry_timeout;
2013 case -ENOBUFS:
2014 rpc_delay(task, HZ >> 2);
2015 goto retry_timeout;
2016 case -EAGAIN:
2017 goto retry_timeout;
2018 case -ETIMEDOUT:
2019 dprintk("RPC: %5u rpcbind request timed out\n",
2020 task->tk_pid);
2021 goto retry_timeout;
2022 case -EPFNOSUPPORT:
2023 /* server doesn't support any rpcbind version we know of */
2024 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
2025 task->tk_pid);
2026 break;
2027 case -EPROTONOSUPPORT:
2028 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
2029 task->tk_pid);
2030 goto retry_timeout;
2031 case -ECONNREFUSED: /* connection problems */
2032 case -ECONNRESET:
2033 case -ECONNABORTED:
2034 case -ENOTCONN:
2035 case -EHOSTDOWN:
2036 case -ENETDOWN:
2037 case -EHOSTUNREACH:
2038 case -ENETUNREACH:
2039 case -EPIPE:
2040 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
2041 task->tk_pid, task->tk_status);
2042 if (!RPC_IS_SOFTCONN(task)) {
2043 rpc_delay(task, 5*HZ);
2044 goto retry_timeout;
2045 }
2046 status = task->tk_status;
2047 break;
2048 default:
2049 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
2050 task->tk_pid, -task->tk_status);
2051 }
2052
2053 rpc_call_rpcerror(task, status);
2054 return;
2055out_next:
2056 task->tk_action = call_connect;
2057 return;
2058retry_timeout:
2059 task->tk_status = 0;
2060 task->tk_action = call_bind;
2061 rpc_check_timeout(task);
2062}
2063
2064/*
2065 * 4b. Connect to the RPC server
2066 */
2067static void
2068call_connect(struct rpc_task *task)
2069{
2070 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2071
2072 if (rpc_task_transmitted(task)) {
2073 rpc_task_handle_transmitted(task);
2074 return;
2075 }
2076
2077 if (xprt_connected(xprt)) {
2078 task->tk_action = call_transmit;
2079 return;
2080 }
2081
2082 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
2083 task->tk_pid, xprt,
2084 (xprt_connected(xprt) ? "is" : "is not"));
2085
2086 task->tk_action = call_connect_status;
2087 if (task->tk_status < 0)
2088 return;
2089 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2090 rpc_call_rpcerror(task, -ENOTCONN);
2091 return;
2092 }
2093 if (!xprt_prepare_transmit(task))
2094 return;
2095 xprt_connect(task);
2096}
2097
2098/*
2099 * 4c. Sort out connect result
2100 */
2101static void
2102call_connect_status(struct rpc_task *task)
2103{
2104 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2105 struct rpc_clnt *clnt = task->tk_client;
2106 int status = task->tk_status;
2107
2108 if (rpc_task_transmitted(task)) {
2109 rpc_task_handle_transmitted(task);
2110 return;
2111 }
2112
2113 dprint_status(task);
2114 trace_rpc_connect_status(task);
2115
2116 if (task->tk_status == 0) {
2117 clnt->cl_stats->netreconn++;
2118 goto out_next;
2119 }
2120 if (xprt_connected(xprt)) {
2121 task->tk_status = 0;
2122 goto out_next;
2123 }
2124
2125 task->tk_status = 0;
2126 switch (status) {
2127 case -ECONNREFUSED:
2128 /* A positive refusal suggests a rebind is needed. */
2129 if (RPC_IS_SOFTCONN(task))
2130 break;
2131 if (clnt->cl_autobind) {
2132 rpc_force_rebind(clnt);
2133 goto out_retry;
2134 }
2135 fallthrough;
2136 case -ECONNRESET:
2137 case -ECONNABORTED:
2138 case -ENETDOWN:
2139 case -ENETUNREACH:
2140 case -EHOSTUNREACH:
2141 case -EPIPE:
2142 case -EPROTO:
2143 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2144 task->tk_rqstp->rq_connect_cookie);
2145 if (RPC_IS_SOFTCONN(task))
2146 break;
2147 /* retry with existing socket, after a delay */
2148 rpc_delay(task, 3*HZ);
2149 fallthrough;
2150 case -EADDRINUSE:
2151 case -ENOTCONN:
2152 case -EAGAIN:
2153 case -ETIMEDOUT:
2154 goto out_retry;
2155 case -ENOBUFS:
2156 rpc_delay(task, HZ >> 2);
2157 goto out_retry;
2158 }
2159 rpc_call_rpcerror(task, status);
2160 return;
2161out_next:
2162 task->tk_action = call_transmit;
2163 return;
2164out_retry:
2165 /* Check for timeouts before looping back to call_bind */
2166 task->tk_action = call_bind;
2167 rpc_check_timeout(task);
2168}
2169
2170/*
2171 * 5. Transmit the RPC request, and wait for reply
2172 */
2173static void
2174call_transmit(struct rpc_task *task)
2175{
2176 if (rpc_task_transmitted(task)) {
2177 rpc_task_handle_transmitted(task);
2178 return;
2179 }
2180
2181 dprint_status(task);
2182
2183 task->tk_action = call_transmit_status;
2184 if (!xprt_prepare_transmit(task))
2185 return;
2186 task->tk_status = 0;
2187 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2188 if (!xprt_connected(task->tk_xprt)) {
2189 task->tk_status = -ENOTCONN;
2190 return;
2191 }
2192 xprt_transmit(task);
2193 }
2194 xprt_end_transmit(task);
2195}
2196
2197/*
2198 * 5a. Handle cleanup after a transmission
2199 */
2200static void
2201call_transmit_status(struct rpc_task *task)
2202{
2203 task->tk_action = call_status;
2204
2205 /*
2206 * Common case: success. Force the compiler to put this
2207 * test first.
2208 */
2209 if (rpc_task_transmitted(task)) {
2210 task->tk_status = 0;
2211 xprt_request_wait_receive(task);
2212 return;
2213 }
2214
2215 switch (task->tk_status) {
2216 default:
2217 dprint_status(task);
2218 break;
2219 case -EBADMSG:
2220 task->tk_status = 0;
2221 task->tk_action = call_encode;
2222 break;
2223 /*
2224 * Special cases: if we've been waiting on the
2225 * socket's write_space() callback, or if the
2226 * socket just returned a connection error,
2227 * then hold onto the transport lock.
2228 */
2229 case -ENOBUFS:
2230 rpc_delay(task, HZ>>2);
2231 fallthrough;
2232 case -EBADSLT:
2233 case -EAGAIN:
2234 task->tk_action = call_transmit;
2235 task->tk_status = 0;
2236 break;
2237 case -ECONNREFUSED:
2238 case -EHOSTDOWN:
2239 case -ENETDOWN:
2240 case -EHOSTUNREACH:
2241 case -ENETUNREACH:
2242 case -EPERM:
2243 if (RPC_IS_SOFTCONN(task)) {
2244 if (!task->tk_msg.rpc_proc->p_proc)
2245 trace_xprt_ping(task->tk_xprt,
2246 task->tk_status);
2247 rpc_call_rpcerror(task, task->tk_status);
2248 return;
2249 }
2250 fallthrough;
2251 case -ECONNRESET:
2252 case -ECONNABORTED:
2253 case -EADDRINUSE:
2254 case -ENOTCONN:
2255 case -EPIPE:
2256 task->tk_action = call_bind;
2257 task->tk_status = 0;
2258 break;
2259 }
2260 rpc_check_timeout(task);
2261}
2262
2263#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2264static void call_bc_transmit(struct rpc_task *task);
2265static void call_bc_transmit_status(struct rpc_task *task);
2266
2267static void
2268call_bc_encode(struct rpc_task *task)
2269{
2270 xprt_request_enqueue_transmit(task);
2271 task->tk_action = call_bc_transmit;
2272}
2273
2274/*
2275 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2276 * addition, disconnect on connectivity errors.
2277 */
2278static void
2279call_bc_transmit(struct rpc_task *task)
2280{
2281 task->tk_action = call_bc_transmit_status;
2282 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2283 if (!xprt_prepare_transmit(task))
2284 return;
2285 task->tk_status = 0;
2286 xprt_transmit(task);
2287 }
2288 xprt_end_transmit(task);
2289}
2290
2291static void
2292call_bc_transmit_status(struct rpc_task *task)
2293{
2294 struct rpc_rqst *req = task->tk_rqstp;
2295
2296 if (rpc_task_transmitted(task))
2297 task->tk_status = 0;
2298
2299 dprint_status(task);
2300
2301 switch (task->tk_status) {
2302 case 0:
2303 /* Success */
2304 case -ENETDOWN:
2305 case -EHOSTDOWN:
2306 case -EHOSTUNREACH:
2307 case -ENETUNREACH:
2308 case -ECONNRESET:
2309 case -ECONNREFUSED:
2310 case -EADDRINUSE:
2311 case -ENOTCONN:
2312 case -EPIPE:
2313 break;
2314 case -ENOBUFS:
2315 rpc_delay(task, HZ>>2);
2316 fallthrough;
2317 case -EBADSLT:
2318 case -EAGAIN:
2319 task->tk_status = 0;
2320 task->tk_action = call_bc_transmit;
2321 return;
2322 case -ETIMEDOUT:
2323 /*
2324 * Problem reaching the server. Disconnect and let the
2325 * forechannel reestablish the connection. The server will
2326 * have to retransmit the backchannel request and we'll
2327 * reprocess it. Since these ops are idempotent, there's no
2328 * need to cache our reply at this time.
2329 */
2330 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2331 "error: %d\n", task->tk_status);
2332 xprt_conditional_disconnect(req->rq_xprt,
2333 req->rq_connect_cookie);
2334 break;
2335 default:
2336 /*
2337 * We were unable to reply and will have to drop the
2338 * request. The server should reconnect and retransmit.
2339 */
2340 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2341 "error: %d\n", task->tk_status);
2342 break;
2343 }
2344 task->tk_action = rpc_exit_task;
2345}
2346#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2347
2348/*
2349 * 6. Sort out the RPC call status
2350 */
2351static void
2352call_status(struct rpc_task *task)
2353{
2354 struct rpc_clnt *clnt = task->tk_client;
2355 int status;
2356
2357 if (!task->tk_msg.rpc_proc->p_proc)
2358 trace_xprt_ping(task->tk_xprt, task->tk_status);
2359
2360 dprint_status(task);
2361
2362 status = task->tk_status;
2363 if (status >= 0) {
2364 task->tk_action = call_decode;
2365 return;
2366 }
2367
2368 trace_rpc_call_status(task);
2369 task->tk_status = 0;
2370 switch(status) {
2371 case -EHOSTDOWN:
2372 case -ENETDOWN:
2373 case -EHOSTUNREACH:
2374 case -ENETUNREACH:
2375 case -EPERM:
2376 if (RPC_IS_SOFTCONN(task))
2377 goto out_exit;
2378 /*
2379 * Delay any retries for 3 seconds, then handle as if it
2380 * were a timeout.
2381 */
2382 rpc_delay(task, 3*HZ);
2383 fallthrough;
2384 case -ETIMEDOUT:
2385 break;
2386 case -ECONNREFUSED:
2387 case -ECONNRESET:
2388 case -ECONNABORTED:
2389 case -ENOTCONN:
2390 rpc_force_rebind(clnt);
2391 break;
2392 case -EADDRINUSE:
2393 rpc_delay(task, 3*HZ);
2394 fallthrough;
2395 case -EPIPE:
2396 case -EAGAIN:
2397 break;
2398 case -EIO:
2399 /* shutdown or soft timeout */
2400 goto out_exit;
2401 default:
2402 if (clnt->cl_chatty)
2403 printk("%s: RPC call returned error %d\n",
2404 clnt->cl_program->name, -status);
2405 goto out_exit;
2406 }
2407 task->tk_action = call_encode;
2408 rpc_check_timeout(task);
2409 return;
2410out_exit:
2411 rpc_call_rpcerror(task, status);
2412}
2413
2414static bool
2415rpc_check_connected(const struct rpc_rqst *req)
2416{
2417 /* No allocated request or transport? return true */
2418 if (!req || !req->rq_xprt)
2419 return true;
2420 return xprt_connected(req->rq_xprt);
2421}
2422
2423static void
2424rpc_check_timeout(struct rpc_task *task)
2425{
2426 struct rpc_clnt *clnt = task->tk_client;
2427
2428 if (RPC_SIGNALLED(task)) {
2429 rpc_call_rpcerror(task, -ERESTARTSYS);
2430 return;
2431 }
2432
2433 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2434 return;
2435
2436 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2437 task->tk_timeouts++;
2438
2439 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2440 rpc_call_rpcerror(task, -ETIMEDOUT);
2441 return;
2442 }
2443
2444 if (RPC_IS_SOFT(task)) {
2445 /*
2446 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2447 * been sent, it should time out only if the transport
2448 * connection gets terminally broken.
2449 */
2450 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2451 rpc_check_connected(task->tk_rqstp))
2452 return;
2453
2454 if (clnt->cl_chatty) {
2455 pr_notice_ratelimited(
2456 "%s: server %s not responding, timed out\n",
2457 clnt->cl_program->name,
2458 task->tk_xprt->servername);
2459 }
2460 if (task->tk_flags & RPC_TASK_TIMEOUT)
2461 rpc_call_rpcerror(task, -ETIMEDOUT);
2462 else
2463 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2464 return;
2465 }
2466
2467 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2468 task->tk_flags |= RPC_CALL_MAJORSEEN;
2469 if (clnt->cl_chatty) {
2470 pr_notice_ratelimited(
2471 "%s: server %s not responding, still trying\n",
2472 clnt->cl_program->name,
2473 task->tk_xprt->servername);
2474 }
2475 }
2476 rpc_force_rebind(clnt);
2477 /*
2478 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2479 * event? RFC2203 requires the server to drop all such requests.
2480 */
2481 rpcauth_invalcred(task);
2482}
2483
2484/*
2485 * 7. Decode the RPC reply
2486 */
2487static void
2488call_decode(struct rpc_task *task)
2489{
2490 struct rpc_clnt *clnt = task->tk_client;
2491 struct rpc_rqst *req = task->tk_rqstp;
2492 struct xdr_stream xdr;
2493 int err;
2494
2495 dprint_status(task);
2496
2497 if (!task->tk_msg.rpc_proc->p_decode) {
2498 task->tk_action = rpc_exit_task;
2499 return;
2500 }
2501
2502 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2503 if (clnt->cl_chatty) {
2504 pr_notice_ratelimited("%s: server %s OK\n",
2505 clnt->cl_program->name,
2506 task->tk_xprt->servername);
2507 }
2508 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2509 }
2510
2511 /*
2512 * Ensure that we see all writes made by xprt_complete_rqst()
2513 * before it changed req->rq_reply_bytes_recvd.
2514 */
2515 smp_rmb();
2516
2517 /*
2518 * Did we ever call xprt_complete_rqst()? If not, we should assume
2519 * the message is incomplete.
2520 */
2521 err = -EAGAIN;
2522 if (!req->rq_reply_bytes_recvd)
2523 goto out;
2524
2525 req->rq_rcv_buf.len = req->rq_private_buf.len;
2526 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2527
2528 /* Check that the softirq receive buffer is valid */
2529 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2530 sizeof(req->rq_rcv_buf)) != 0);
2531
2532 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2533 req->rq_rcv_buf.head[0].iov_base, req);
2534 err = rpc_decode_header(task, &xdr);
2535out:
2536 switch (err) {
2537 case 0:
2538 task->tk_action = rpc_exit_task;
2539 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2540 dprintk("RPC: %5u %s result %d\n",
2541 task->tk_pid, __func__, task->tk_status);
2542 return;
2543 case -EAGAIN:
2544 task->tk_status = 0;
2545 if (task->tk_client->cl_discrtry)
2546 xprt_conditional_disconnect(req->rq_xprt,
2547 req->rq_connect_cookie);
2548 task->tk_action = call_encode;
2549 rpc_check_timeout(task);
2550 break;
2551 case -EKEYREJECTED:
2552 task->tk_action = call_reserve;
2553 rpc_check_timeout(task);
2554 rpcauth_invalcred(task);
2555 /* Ensure we obtain a new XID if we retry! */
2556 xprt_release(task);
2557 }
2558}
2559
2560static int
2561rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2562{
2563 struct rpc_clnt *clnt = task->tk_client;
2564 struct rpc_rqst *req = task->tk_rqstp;
2565 __be32 *p;
2566 int error;
2567
2568 error = -EMSGSIZE;
2569 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2570 if (!p)
2571 goto out_fail;
2572 *p++ = req->rq_xid;
2573 *p++ = rpc_call;
2574 *p++ = cpu_to_be32(RPC_VERSION);
2575 *p++ = cpu_to_be32(clnt->cl_prog);
2576 *p++ = cpu_to_be32(clnt->cl_vers);
2577 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2578
2579 error = rpcauth_marshcred(task, xdr);
2580 if (error < 0)
2581 goto out_fail;
2582 return 0;
2583out_fail:
2584 trace_rpc_bad_callhdr(task);
2585 rpc_call_rpcerror(task, error);
2586 return error;
2587}
2588
2589static noinline int
2590rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2591{
2592 struct rpc_clnt *clnt = task->tk_client;
2593 int error;
2594 __be32 *p;
2595
2596 /* RFC-1014 says that the representation of XDR data must be a
2597 * multiple of four bytes
2598 * - if it isn't pointer subtraction in the NFS client may give
2599 * undefined results
2600 */
2601 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2602 goto out_unparsable;
2603
2604 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2605 if (!p)
2606 goto out_unparsable;
2607 p++; /* skip XID */
2608 if (*p++ != rpc_reply)
2609 goto out_unparsable;
2610 if (*p++ != rpc_msg_accepted)
2611 goto out_msg_denied;
2612
2613 error = rpcauth_checkverf(task, xdr);
2614 if (error)
2615 goto out_verifier;
2616
2617 p = xdr_inline_decode(xdr, sizeof(*p));
2618 if (!p)
2619 goto out_unparsable;
2620 switch (*p) {
2621 case rpc_success:
2622 return 0;
2623 case rpc_prog_unavail:
2624 trace_rpc__prog_unavail(task);
2625 error = -EPFNOSUPPORT;
2626 goto out_err;
2627 case rpc_prog_mismatch:
2628 trace_rpc__prog_mismatch(task);
2629 error = -EPROTONOSUPPORT;
2630 goto out_err;
2631 case rpc_proc_unavail:
2632 trace_rpc__proc_unavail(task);
2633 error = -EOPNOTSUPP;
2634 goto out_err;
2635 case rpc_garbage_args:
2636 case rpc_system_err:
2637 trace_rpc__garbage_args(task);
2638 error = -EIO;
2639 break;
2640 default:
2641 goto out_unparsable;
2642 }
2643
2644out_garbage:
2645 clnt->cl_stats->rpcgarbage++;
2646 if (task->tk_garb_retry) {
2647 task->tk_garb_retry--;
2648 task->tk_action = call_encode;
2649 return -EAGAIN;
2650 }
2651out_err:
2652 rpc_call_rpcerror(task, error);
2653 return error;
2654
2655out_unparsable:
2656 trace_rpc__unparsable(task);
2657 error = -EIO;
2658 goto out_garbage;
2659
2660out_verifier:
2661 trace_rpc_bad_verifier(task);
2662 goto out_garbage;
2663
2664out_msg_denied:
2665 error = -EACCES;
2666 p = xdr_inline_decode(xdr, sizeof(*p));
2667 if (!p)
2668 goto out_unparsable;
2669 switch (*p++) {
2670 case rpc_auth_error:
2671 break;
2672 case rpc_mismatch:
2673 trace_rpc__mismatch(task);
2674 error = -EPROTONOSUPPORT;
2675 goto out_err;
2676 default:
2677 goto out_unparsable;
2678 }
2679
2680 p = xdr_inline_decode(xdr, sizeof(*p));
2681 if (!p)
2682 goto out_unparsable;
2683 switch (*p++) {
2684 case rpc_autherr_rejectedcred:
2685 case rpc_autherr_rejectedverf:
2686 case rpcsec_gsserr_credproblem:
2687 case rpcsec_gsserr_ctxproblem:
2688 if (!task->tk_cred_retry)
2689 break;
2690 task->tk_cred_retry--;
2691 trace_rpc__stale_creds(task);
2692 return -EKEYREJECTED;
2693 case rpc_autherr_badcred:
2694 case rpc_autherr_badverf:
2695 /* possibly garbled cred/verf? */
2696 if (!task->tk_garb_retry)
2697 break;
2698 task->tk_garb_retry--;
2699 trace_rpc__bad_creds(task);
2700 task->tk_action = call_encode;
2701 return -EAGAIN;
2702 case rpc_autherr_tooweak:
2703 trace_rpc__auth_tooweak(task);
2704 pr_warn("RPC: server %s requires stronger authentication.\n",
2705 task->tk_xprt->servername);
2706 break;
2707 default:
2708 goto out_unparsable;
2709 }
2710 goto out_err;
2711}
2712
2713static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2714 const void *obj)
2715{
2716}
2717
2718static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2719 void *obj)
2720{
2721 return 0;
2722}
2723
2724static const struct rpc_procinfo rpcproc_null = {
2725 .p_encode = rpcproc_encode_null,
2726 .p_decode = rpcproc_decode_null,
2727};
2728
2729static int rpc_ping(struct rpc_clnt *clnt)
2730{
2731 struct rpc_message msg = {
2732 .rpc_proc = &rpcproc_null,
2733 };
2734 int err;
2735 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2736 RPC_TASK_NULLCREDS);
2737 return err;
2738}
2739
2740static
2741struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2742 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2743 const struct rpc_call_ops *ops, void *data)
2744{
2745 struct rpc_message msg = {
2746 .rpc_proc = &rpcproc_null,
2747 };
2748 struct rpc_task_setup task_setup_data = {
2749 .rpc_client = clnt,
2750 .rpc_xprt = xprt,
2751 .rpc_message = &msg,
2752 .rpc_op_cred = cred,
2753 .callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
2754 .callback_data = data,
2755 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2756 RPC_TASK_NULLCREDS,
2757 };
2758
2759 return rpc_run_task(&task_setup_data);
2760}
2761
2762struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2763{
2764 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2765}
2766EXPORT_SYMBOL_GPL(rpc_call_null);
2767
2768struct rpc_cb_add_xprt_calldata {
2769 struct rpc_xprt_switch *xps;
2770 struct rpc_xprt *xprt;
2771};
2772
2773static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2774{
2775 struct rpc_cb_add_xprt_calldata *data = calldata;
2776
2777 if (task->tk_status == 0)
2778 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2779}
2780
2781static void rpc_cb_add_xprt_release(void *calldata)
2782{
2783 struct rpc_cb_add_xprt_calldata *data = calldata;
2784
2785 xprt_put(data->xprt);
2786 xprt_switch_put(data->xps);
2787 kfree(data);
2788}
2789
2790static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2791 .rpc_call_done = rpc_cb_add_xprt_done,
2792 .rpc_release = rpc_cb_add_xprt_release,
2793};
2794
2795/**
2796 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2797 * @clnt: pointer to struct rpc_clnt
2798 * @xps: pointer to struct rpc_xprt_switch,
2799 * @xprt: pointer struct rpc_xprt
2800 * @dummy: unused
2801 */
2802int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2803 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2804 void *dummy)
2805{
2806 struct rpc_cb_add_xprt_calldata *data;
2807 struct rpc_task *task;
2808
2809 data = kmalloc(sizeof(*data), GFP_NOFS);
2810 if (!data)
2811 return -ENOMEM;
2812 data->xps = xprt_switch_get(xps);
2813 data->xprt = xprt_get(xprt);
2814 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2815 rpc_cb_add_xprt_release(data);
2816 goto success;
2817 }
2818
2819 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2820 &rpc_cb_add_xprt_call_ops, data);
2821
2822 rpc_put_task(task);
2823success:
2824 return 1;
2825}
2826EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2827
2828/**
2829 * rpc_clnt_setup_test_and_add_xprt()
2830 *
2831 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2832 * 1) caller of the test function must dereference the rpc_xprt_switch
2833 * and the rpc_xprt.
2834 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2835 * the rpc_call_done routine.
2836 *
2837 * Upon success (return of 1), the test function adds the new
2838 * transport to the rpc_clnt xprt switch
2839 *
2840 * @clnt: struct rpc_clnt to get the new transport
2841 * @xps: the rpc_xprt_switch to hold the new transport
2842 * @xprt: the rpc_xprt to test
2843 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2844 * and test function call data
2845 */
2846int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2847 struct rpc_xprt_switch *xps,
2848 struct rpc_xprt *xprt,
2849 void *data)
2850{
2851 struct rpc_task *task;
2852 struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
2853 int status = -EADDRINUSE;
2854
2855 xprt = xprt_get(xprt);
2856 xprt_switch_get(xps);
2857
2858 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2859 goto out_err;
2860
2861 /* Test the connection */
2862 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2863 if (IS_ERR(task)) {
2864 status = PTR_ERR(task);
2865 goto out_err;
2866 }
2867 status = task->tk_status;
2868 rpc_put_task(task);
2869
2870 if (status < 0)
2871 goto out_err;
2872
2873 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2874 xtest->add_xprt_test(clnt, xprt, xtest->data);
2875
2876 xprt_put(xprt);
2877 xprt_switch_put(xps);
2878
2879 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
2880 return 1;
2881out_err:
2882 xprt_put(xprt);
2883 xprt_switch_put(xps);
2884 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n",
2885 status, xprt->address_strings[RPC_DISPLAY_ADDR]);
2886 return status;
2887}
2888EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
2889
2890/**
2891 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
2892 * @clnt: pointer to struct rpc_clnt
2893 * @xprtargs: pointer to struct xprt_create
2894 * @setup: callback to test and/or set up the connection
2895 * @data: pointer to setup function data
2896 *
2897 * Creates a new transport using the parameters set in args and
2898 * adds it to clnt.
2899 * If ping is set, then test that connectivity succeeds before
2900 * adding the new transport.
2901 *
2902 */
2903int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
2904 struct xprt_create *xprtargs,
2905 int (*setup)(struct rpc_clnt *,
2906 struct rpc_xprt_switch *,
2907 struct rpc_xprt *,
2908 void *),
2909 void *data)
2910{
2911 struct rpc_xprt_switch *xps;
2912 struct rpc_xprt *xprt;
2913 unsigned long connect_timeout;
2914 unsigned long reconnect_timeout;
2915 unsigned char resvport, reuseport;
2916 int ret = 0;
2917
2918 rcu_read_lock();
2919 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2920 xprt = xprt_iter_xprt(&clnt->cl_xpi);
2921 if (xps == NULL || xprt == NULL) {
2922 rcu_read_unlock();
2923 xprt_switch_put(xps);
2924 return -EAGAIN;
2925 }
2926 resvport = xprt->resvport;
2927 reuseport = xprt->reuseport;
2928 connect_timeout = xprt->connect_timeout;
2929 reconnect_timeout = xprt->max_reconnect_timeout;
2930 rcu_read_unlock();
2931
2932 xprt = xprt_create_transport(xprtargs);
2933 if (IS_ERR(xprt)) {
2934 ret = PTR_ERR(xprt);
2935 goto out_put_switch;
2936 }
2937 xprt->resvport = resvport;
2938 xprt->reuseport = reuseport;
2939 if (xprt->ops->set_connect_timeout != NULL)
2940 xprt->ops->set_connect_timeout(xprt,
2941 connect_timeout,
2942 reconnect_timeout);
2943
2944 rpc_xprt_switch_set_roundrobin(xps);
2945 if (setup) {
2946 ret = setup(clnt, xps, xprt, data);
2947 if (ret != 0)
2948 goto out_put_xprt;
2949 }
2950 rpc_xprt_switch_add_xprt(xps, xprt);
2951out_put_xprt:
2952 xprt_put(xprt);
2953out_put_switch:
2954 xprt_switch_put(xps);
2955 return ret;
2956}
2957EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
2958
2959struct connect_timeout_data {
2960 unsigned long connect_timeout;
2961 unsigned long reconnect_timeout;
2962};
2963
2964static int
2965rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
2966 struct rpc_xprt *xprt,
2967 void *data)
2968{
2969 struct connect_timeout_data *timeo = data;
2970
2971 if (xprt->ops->set_connect_timeout)
2972 xprt->ops->set_connect_timeout(xprt,
2973 timeo->connect_timeout,
2974 timeo->reconnect_timeout);
2975 return 0;
2976}
2977
2978void
2979rpc_set_connect_timeout(struct rpc_clnt *clnt,
2980 unsigned long connect_timeout,
2981 unsigned long reconnect_timeout)
2982{
2983 struct connect_timeout_data timeout = {
2984 .connect_timeout = connect_timeout,
2985 .reconnect_timeout = reconnect_timeout,
2986 };
2987 rpc_clnt_iterate_for_each_xprt(clnt,
2988 rpc_xprt_set_connect_timeout,
2989 &timeout);
2990}
2991EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
2992
2993void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
2994{
2995 rcu_read_lock();
2996 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2997 rcu_read_unlock();
2998}
2999EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
3000
3001void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3002{
3003 rcu_read_lock();
3004 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3005 xprt);
3006 rcu_read_unlock();
3007}
3008EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3009
3010bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3011 const struct sockaddr *sap)
3012{
3013 struct rpc_xprt_switch *xps;
3014 bool ret;
3015
3016 rcu_read_lock();
3017 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3018 ret = rpc_xprt_switch_has_addr(xps, sap);
3019 rcu_read_unlock();
3020 return ret;
3021}
3022EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3023
3024#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3025static void rpc_show_header(void)
3026{
3027 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3028 "-timeout ---ops--\n");
3029}
3030
3031static void rpc_show_task(const struct rpc_clnt *clnt,
3032 const struct rpc_task *task)
3033{
3034 const char *rpc_waitq = "none";
3035
3036 if (RPC_IS_QUEUED(task))
3037 rpc_waitq = rpc_qname(task->tk_waitqueue);
3038
3039 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3040 task->tk_pid, task->tk_flags, task->tk_status,
3041 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3042 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3043 task->tk_action, rpc_waitq);
3044}
3045
3046void rpc_show_tasks(struct net *net)
3047{
3048 struct rpc_clnt *clnt;
3049 struct rpc_task *task;
3050 int header = 0;
3051 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3052
3053 spin_lock(&sn->rpc_client_lock);
3054 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3055 spin_lock(&clnt->cl_lock);
3056 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3057 if (!header) {
3058 rpc_show_header();
3059 header++;
3060 }
3061 rpc_show_task(clnt, task);
3062 }
3063 spin_unlock(&clnt->cl_lock);
3064 }
3065 spin_unlock(&sn->rpc_client_lock);
3066}
3067#endif
3068
3069#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3070static int
3071rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3072 struct rpc_xprt *xprt,
3073 void *dummy)
3074{
3075 return xprt_enable_swap(xprt);
3076}
3077
3078int
3079rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3080{
3081 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3082 return rpc_clnt_iterate_for_each_xprt(clnt,
3083 rpc_clnt_swap_activate_callback, NULL);
3084 return 0;
3085}
3086EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3087
3088static int
3089rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3090 struct rpc_xprt *xprt,
3091 void *dummy)
3092{
3093 xprt_disable_swap(xprt);
3094 return 0;
3095}
3096
3097void
3098rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3099{
3100 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3101 rpc_clnt_iterate_for_each_xprt(clnt,
3102 rpc_clnt_swap_deactivate_callback, NULL);
3103}
3104EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3105#endif /* CONFIG_SUNRPC_SWAP */
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#include <asm/system.h>
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.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/rpc_pipe_fs.h>
37#include <linux/sunrpc/metrics.h>
38#include <linux/sunrpc/bc_xprt.h>
39
40#include "sunrpc.h"
41
42#ifdef RPC_DEBUG
43# define RPCDBG_FACILITY RPCDBG_CALL
44#endif
45
46#define dprint_status(t) \
47 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
48 __func__, t->tk_status)
49
50/*
51 * All RPC clients are linked into this list
52 */
53static LIST_HEAD(all_clients);
54static DEFINE_SPINLOCK(rpc_client_lock);
55
56static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
57
58
59static void call_start(struct rpc_task *task);
60static void call_reserve(struct rpc_task *task);
61static void call_reserveresult(struct rpc_task *task);
62static void call_allocate(struct rpc_task *task);
63static void call_decode(struct rpc_task *task);
64static void call_bind(struct rpc_task *task);
65static void call_bind_status(struct rpc_task *task);
66static void call_transmit(struct rpc_task *task);
67#if defined(CONFIG_SUNRPC_BACKCHANNEL)
68static void call_bc_transmit(struct rpc_task *task);
69#endif /* CONFIG_SUNRPC_BACKCHANNEL */
70static void call_status(struct rpc_task *task);
71static void call_transmit_status(struct rpc_task *task);
72static void call_refresh(struct rpc_task *task);
73static void call_refreshresult(struct rpc_task *task);
74static void call_timeout(struct rpc_task *task);
75static void call_connect(struct rpc_task *task);
76static void call_connect_status(struct rpc_task *task);
77
78static __be32 *rpc_encode_header(struct rpc_task *task);
79static __be32 *rpc_verify_header(struct rpc_task *task);
80static int rpc_ping(struct rpc_clnt *clnt);
81
82static void rpc_register_client(struct rpc_clnt *clnt)
83{
84 spin_lock(&rpc_client_lock);
85 list_add(&clnt->cl_clients, &all_clients);
86 spin_unlock(&rpc_client_lock);
87}
88
89static void rpc_unregister_client(struct rpc_clnt *clnt)
90{
91 spin_lock(&rpc_client_lock);
92 list_del(&clnt->cl_clients);
93 spin_unlock(&rpc_client_lock);
94}
95
96static int
97rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
98{
99 static uint32_t clntid;
100 struct path path, dir;
101 char name[15];
102 struct qstr q = {
103 .name = name,
104 };
105 int error;
106
107 clnt->cl_path.mnt = ERR_PTR(-ENOENT);
108 clnt->cl_path.dentry = ERR_PTR(-ENOENT);
109 if (dir_name == NULL)
110 return 0;
111
112 path.mnt = rpc_get_mount();
113 if (IS_ERR(path.mnt))
114 return PTR_ERR(path.mnt);
115 error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &dir);
116 if (error)
117 goto err;
118
119 for (;;) {
120 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
121 name[sizeof(name) - 1] = '\0';
122 q.hash = full_name_hash(q.name, q.len);
123 path.dentry = rpc_create_client_dir(dir.dentry, &q, clnt);
124 if (!IS_ERR(path.dentry))
125 break;
126 error = PTR_ERR(path.dentry);
127 if (error != -EEXIST) {
128 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
129 " %s/%s, error %d\n",
130 dir_name, name, error);
131 goto err_path_put;
132 }
133 }
134 path_put(&dir);
135 clnt->cl_path = path;
136 return 0;
137err_path_put:
138 path_put(&dir);
139err:
140 rpc_put_mount();
141 return error;
142}
143
144static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
145{
146 struct rpc_program *program = args->program;
147 struct rpc_version *version;
148 struct rpc_clnt *clnt = NULL;
149 struct rpc_auth *auth;
150 int err;
151 size_t len;
152
153 /* sanity check the name before trying to print it */
154 err = -EINVAL;
155 len = strlen(args->servername);
156 if (len > RPC_MAXNETNAMELEN)
157 goto out_no_rpciod;
158 len++;
159
160 dprintk("RPC: creating %s client for %s (xprt %p)\n",
161 program->name, args->servername, xprt);
162
163 err = rpciod_up();
164 if (err)
165 goto out_no_rpciod;
166 err = -EINVAL;
167 if (!xprt)
168 goto out_no_xprt;
169
170 if (args->version >= program->nrvers)
171 goto out_err;
172 version = program->version[args->version];
173 if (version == NULL)
174 goto out_err;
175
176 err = -ENOMEM;
177 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
178 if (!clnt)
179 goto out_err;
180 clnt->cl_parent = clnt;
181
182 clnt->cl_server = clnt->cl_inline_name;
183 if (len > sizeof(clnt->cl_inline_name)) {
184 char *buf = kmalloc(len, GFP_KERNEL);
185 if (buf != NULL)
186 clnt->cl_server = buf;
187 else
188 len = sizeof(clnt->cl_inline_name);
189 }
190 strlcpy(clnt->cl_server, args->servername, len);
191
192 clnt->cl_xprt = xprt;
193 clnt->cl_procinfo = version->procs;
194 clnt->cl_maxproc = version->nrprocs;
195 clnt->cl_protname = program->name;
196 clnt->cl_prog = args->prognumber ? : program->number;
197 clnt->cl_vers = version->number;
198 clnt->cl_stats = program->stats;
199 clnt->cl_metrics = rpc_alloc_iostats(clnt);
200 err = -ENOMEM;
201 if (clnt->cl_metrics == NULL)
202 goto out_no_stats;
203 clnt->cl_program = program;
204 INIT_LIST_HEAD(&clnt->cl_tasks);
205 spin_lock_init(&clnt->cl_lock);
206
207 if (!xprt_bound(clnt->cl_xprt))
208 clnt->cl_autobind = 1;
209
210 clnt->cl_timeout = xprt->timeout;
211 if (args->timeout != NULL) {
212 memcpy(&clnt->cl_timeout_default, args->timeout,
213 sizeof(clnt->cl_timeout_default));
214 clnt->cl_timeout = &clnt->cl_timeout_default;
215 }
216
217 clnt->cl_rtt = &clnt->cl_rtt_default;
218 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
219 clnt->cl_principal = NULL;
220 if (args->client_name) {
221 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
222 if (!clnt->cl_principal)
223 goto out_no_principal;
224 }
225
226 atomic_set(&clnt->cl_count, 1);
227
228 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
229 if (err < 0)
230 goto out_no_path;
231
232 auth = rpcauth_create(args->authflavor, clnt);
233 if (IS_ERR(auth)) {
234 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
235 args->authflavor);
236 err = PTR_ERR(auth);
237 goto out_no_auth;
238 }
239
240 /* save the nodename */
241 clnt->cl_nodelen = strlen(init_utsname()->nodename);
242 if (clnt->cl_nodelen > UNX_MAXNODENAME)
243 clnt->cl_nodelen = UNX_MAXNODENAME;
244 memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen);
245 rpc_register_client(clnt);
246 return clnt;
247
248out_no_auth:
249 if (!IS_ERR(clnt->cl_path.dentry)) {
250 rpc_remove_client_dir(clnt->cl_path.dentry);
251 rpc_put_mount();
252 }
253out_no_path:
254 kfree(clnt->cl_principal);
255out_no_principal:
256 rpc_free_iostats(clnt->cl_metrics);
257out_no_stats:
258 if (clnt->cl_server != clnt->cl_inline_name)
259 kfree(clnt->cl_server);
260 kfree(clnt);
261out_err:
262 xprt_put(xprt);
263out_no_xprt:
264 rpciod_down();
265out_no_rpciod:
266 return ERR_PTR(err);
267}
268
269/*
270 * rpc_create - create an RPC client and transport with one call
271 * @args: rpc_clnt create argument structure
272 *
273 * Creates and initializes an RPC transport and an RPC client.
274 *
275 * It can ping the server in order to determine if it is up, and to see if
276 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
277 * this behavior so asynchronous tasks can also use rpc_create.
278 */
279struct rpc_clnt *rpc_create(struct rpc_create_args *args)
280{
281 struct rpc_xprt *xprt;
282 struct rpc_clnt *clnt;
283 struct xprt_create xprtargs = {
284 .net = args->net,
285 .ident = args->protocol,
286 .srcaddr = args->saddress,
287 .dstaddr = args->address,
288 .addrlen = args->addrsize,
289 .bc_xprt = args->bc_xprt,
290 };
291 char servername[48];
292
293 /*
294 * If the caller chooses not to specify a hostname, whip
295 * up a string representation of the passed-in address.
296 */
297 if (args->servername == NULL) {
298 struct sockaddr_un *sun =
299 (struct sockaddr_un *)args->address;
300 struct sockaddr_in *sin =
301 (struct sockaddr_in *)args->address;
302 struct sockaddr_in6 *sin6 =
303 (struct sockaddr_in6 *)args->address;
304
305 servername[0] = '\0';
306 switch (args->address->sa_family) {
307 case AF_LOCAL:
308 snprintf(servername, sizeof(servername), "%s",
309 sun->sun_path);
310 break;
311 case AF_INET:
312 snprintf(servername, sizeof(servername), "%pI4",
313 &sin->sin_addr.s_addr);
314 break;
315 case AF_INET6:
316 snprintf(servername, sizeof(servername), "%pI6",
317 &sin6->sin6_addr);
318 break;
319 default:
320 /* caller wants default server name, but
321 * address family isn't recognized. */
322 return ERR_PTR(-EINVAL);
323 }
324 args->servername = servername;
325 }
326
327 xprt = xprt_create_transport(&xprtargs);
328 if (IS_ERR(xprt))
329 return (struct rpc_clnt *)xprt;
330
331 /*
332 * By default, kernel RPC client connects from a reserved port.
333 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
334 * but it is always enabled for rpciod, which handles the connect
335 * operation.
336 */
337 xprt->resvport = 1;
338 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
339 xprt->resvport = 0;
340
341 clnt = rpc_new_client(args, xprt);
342 if (IS_ERR(clnt))
343 return clnt;
344
345 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
346 int err = rpc_ping(clnt);
347 if (err != 0) {
348 rpc_shutdown_client(clnt);
349 return ERR_PTR(err);
350 }
351 }
352
353 clnt->cl_softrtry = 1;
354 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
355 clnt->cl_softrtry = 0;
356
357 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
358 clnt->cl_autobind = 1;
359 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
360 clnt->cl_discrtry = 1;
361 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
362 clnt->cl_chatty = 1;
363
364 return clnt;
365}
366EXPORT_SYMBOL_GPL(rpc_create);
367
368/*
369 * This function clones the RPC client structure. It allows us to share the
370 * same transport while varying parameters such as the authentication
371 * flavour.
372 */
373struct rpc_clnt *
374rpc_clone_client(struct rpc_clnt *clnt)
375{
376 struct rpc_clnt *new;
377 int err = -ENOMEM;
378
379 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
380 if (!new)
381 goto out_no_clnt;
382 new->cl_parent = clnt;
383 /* Turn off autobind on clones */
384 new->cl_autobind = 0;
385 INIT_LIST_HEAD(&new->cl_tasks);
386 spin_lock_init(&new->cl_lock);
387 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
388 new->cl_metrics = rpc_alloc_iostats(clnt);
389 if (new->cl_metrics == NULL)
390 goto out_no_stats;
391 if (clnt->cl_principal) {
392 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
393 if (new->cl_principal == NULL)
394 goto out_no_principal;
395 }
396 atomic_set(&new->cl_count, 1);
397 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
398 if (err != 0)
399 goto out_no_path;
400 if (new->cl_auth)
401 atomic_inc(&new->cl_auth->au_count);
402 xprt_get(clnt->cl_xprt);
403 atomic_inc(&clnt->cl_count);
404 rpc_register_client(new);
405 rpciod_up();
406 return new;
407out_no_path:
408 kfree(new->cl_principal);
409out_no_principal:
410 rpc_free_iostats(new->cl_metrics);
411out_no_stats:
412 kfree(new);
413out_no_clnt:
414 dprintk("RPC: %s: returned error %d\n", __func__, err);
415 return ERR_PTR(err);
416}
417EXPORT_SYMBOL_GPL(rpc_clone_client);
418
419/*
420 * Kill all tasks for the given client.
421 * XXX: kill their descendants as well?
422 */
423void rpc_killall_tasks(struct rpc_clnt *clnt)
424{
425 struct rpc_task *rovr;
426
427
428 if (list_empty(&clnt->cl_tasks))
429 return;
430 dprintk("RPC: killing all tasks for client %p\n", clnt);
431 /*
432 * Spin lock all_tasks to prevent changes...
433 */
434 spin_lock(&clnt->cl_lock);
435 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
436 if (!RPC_IS_ACTIVATED(rovr))
437 continue;
438 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
439 rovr->tk_flags |= RPC_TASK_KILLED;
440 rpc_exit(rovr, -EIO);
441 if (RPC_IS_QUEUED(rovr))
442 rpc_wake_up_queued_task(rovr->tk_waitqueue,
443 rovr);
444 }
445 }
446 spin_unlock(&clnt->cl_lock);
447}
448EXPORT_SYMBOL_GPL(rpc_killall_tasks);
449
450/*
451 * Properly shut down an RPC client, terminating all outstanding
452 * requests.
453 */
454void rpc_shutdown_client(struct rpc_clnt *clnt)
455{
456 dprintk("RPC: shutting down %s client for %s\n",
457 clnt->cl_protname, clnt->cl_server);
458
459 while (!list_empty(&clnt->cl_tasks)) {
460 rpc_killall_tasks(clnt);
461 wait_event_timeout(destroy_wait,
462 list_empty(&clnt->cl_tasks), 1*HZ);
463 }
464
465 rpc_release_client(clnt);
466}
467EXPORT_SYMBOL_GPL(rpc_shutdown_client);
468
469/*
470 * Free an RPC client
471 */
472static void
473rpc_free_client(struct rpc_clnt *clnt)
474{
475 dprintk("RPC: destroying %s client for %s\n",
476 clnt->cl_protname, clnt->cl_server);
477 if (!IS_ERR(clnt->cl_path.dentry)) {
478 rpc_remove_client_dir(clnt->cl_path.dentry);
479 rpc_put_mount();
480 }
481 if (clnt->cl_parent != clnt) {
482 rpc_release_client(clnt->cl_parent);
483 goto out_free;
484 }
485 if (clnt->cl_server != clnt->cl_inline_name)
486 kfree(clnt->cl_server);
487out_free:
488 rpc_unregister_client(clnt);
489 rpc_free_iostats(clnt->cl_metrics);
490 kfree(clnt->cl_principal);
491 clnt->cl_metrics = NULL;
492 xprt_put(clnt->cl_xprt);
493 rpciod_down();
494 kfree(clnt);
495}
496
497/*
498 * Free an RPC client
499 */
500static void
501rpc_free_auth(struct rpc_clnt *clnt)
502{
503 if (clnt->cl_auth == NULL) {
504 rpc_free_client(clnt);
505 return;
506 }
507
508 /*
509 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
510 * release remaining GSS contexts. This mechanism ensures
511 * that it can do so safely.
512 */
513 atomic_inc(&clnt->cl_count);
514 rpcauth_release(clnt->cl_auth);
515 clnt->cl_auth = NULL;
516 if (atomic_dec_and_test(&clnt->cl_count))
517 rpc_free_client(clnt);
518}
519
520/*
521 * Release reference to the RPC client
522 */
523void
524rpc_release_client(struct rpc_clnt *clnt)
525{
526 dprintk("RPC: rpc_release_client(%p)\n", clnt);
527
528 if (list_empty(&clnt->cl_tasks))
529 wake_up(&destroy_wait);
530 if (atomic_dec_and_test(&clnt->cl_count))
531 rpc_free_auth(clnt);
532}
533
534/**
535 * rpc_bind_new_program - bind a new RPC program to an existing client
536 * @old: old rpc_client
537 * @program: rpc program to set
538 * @vers: rpc program version
539 *
540 * Clones the rpc client and sets up a new RPC program. This is mainly
541 * of use for enabling different RPC programs to share the same transport.
542 * The Sun NFSv2/v3 ACL protocol can do this.
543 */
544struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
545 struct rpc_program *program,
546 u32 vers)
547{
548 struct rpc_clnt *clnt;
549 struct rpc_version *version;
550 int err;
551
552 BUG_ON(vers >= program->nrvers || !program->version[vers]);
553 version = program->version[vers];
554 clnt = rpc_clone_client(old);
555 if (IS_ERR(clnt))
556 goto out;
557 clnt->cl_procinfo = version->procs;
558 clnt->cl_maxproc = version->nrprocs;
559 clnt->cl_protname = program->name;
560 clnt->cl_prog = program->number;
561 clnt->cl_vers = version->number;
562 clnt->cl_stats = program->stats;
563 err = rpc_ping(clnt);
564 if (err != 0) {
565 rpc_shutdown_client(clnt);
566 clnt = ERR_PTR(err);
567 }
568out:
569 return clnt;
570}
571EXPORT_SYMBOL_GPL(rpc_bind_new_program);
572
573void rpc_task_release_client(struct rpc_task *task)
574{
575 struct rpc_clnt *clnt = task->tk_client;
576
577 if (clnt != NULL) {
578 /* Remove from client task list */
579 spin_lock(&clnt->cl_lock);
580 list_del(&task->tk_task);
581 spin_unlock(&clnt->cl_lock);
582 task->tk_client = NULL;
583
584 rpc_release_client(clnt);
585 }
586}
587
588static
589void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
590{
591 if (clnt != NULL) {
592 rpc_task_release_client(task);
593 task->tk_client = clnt;
594 atomic_inc(&clnt->cl_count);
595 if (clnt->cl_softrtry)
596 task->tk_flags |= RPC_TASK_SOFT;
597 /* Add to the client's list of all tasks */
598 spin_lock(&clnt->cl_lock);
599 list_add_tail(&task->tk_task, &clnt->cl_tasks);
600 spin_unlock(&clnt->cl_lock);
601 }
602}
603
604void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
605{
606 rpc_task_release_client(task);
607 rpc_task_set_client(task, clnt);
608}
609EXPORT_SYMBOL_GPL(rpc_task_reset_client);
610
611
612static void
613rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
614{
615 if (msg != NULL) {
616 task->tk_msg.rpc_proc = msg->rpc_proc;
617 task->tk_msg.rpc_argp = msg->rpc_argp;
618 task->tk_msg.rpc_resp = msg->rpc_resp;
619 if (msg->rpc_cred != NULL)
620 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
621 }
622}
623
624/*
625 * Default callback for async RPC calls
626 */
627static void
628rpc_default_callback(struct rpc_task *task, void *data)
629{
630}
631
632static const struct rpc_call_ops rpc_default_ops = {
633 .rpc_call_done = rpc_default_callback,
634};
635
636/**
637 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
638 * @task_setup_data: pointer to task initialisation data
639 */
640struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
641{
642 struct rpc_task *task;
643
644 task = rpc_new_task(task_setup_data);
645 if (IS_ERR(task))
646 goto out;
647
648 rpc_task_set_client(task, task_setup_data->rpc_client);
649 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
650
651 if (task->tk_action == NULL)
652 rpc_call_start(task);
653
654 atomic_inc(&task->tk_count);
655 rpc_execute(task);
656out:
657 return task;
658}
659EXPORT_SYMBOL_GPL(rpc_run_task);
660
661/**
662 * rpc_call_sync - Perform a synchronous RPC call
663 * @clnt: pointer to RPC client
664 * @msg: RPC call parameters
665 * @flags: RPC call flags
666 */
667int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
668{
669 struct rpc_task *task;
670 struct rpc_task_setup task_setup_data = {
671 .rpc_client = clnt,
672 .rpc_message = msg,
673 .callback_ops = &rpc_default_ops,
674 .flags = flags,
675 };
676 int status;
677
678 BUG_ON(flags & RPC_TASK_ASYNC);
679
680 task = rpc_run_task(&task_setup_data);
681 if (IS_ERR(task))
682 return PTR_ERR(task);
683 status = task->tk_status;
684 rpc_put_task(task);
685 return status;
686}
687EXPORT_SYMBOL_GPL(rpc_call_sync);
688
689/**
690 * rpc_call_async - Perform an asynchronous RPC call
691 * @clnt: pointer to RPC client
692 * @msg: RPC call parameters
693 * @flags: RPC call flags
694 * @tk_ops: RPC call ops
695 * @data: user call data
696 */
697int
698rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
699 const struct rpc_call_ops *tk_ops, void *data)
700{
701 struct rpc_task *task;
702 struct rpc_task_setup task_setup_data = {
703 .rpc_client = clnt,
704 .rpc_message = msg,
705 .callback_ops = tk_ops,
706 .callback_data = data,
707 .flags = flags|RPC_TASK_ASYNC,
708 };
709
710 task = rpc_run_task(&task_setup_data);
711 if (IS_ERR(task))
712 return PTR_ERR(task);
713 rpc_put_task(task);
714 return 0;
715}
716EXPORT_SYMBOL_GPL(rpc_call_async);
717
718#if defined(CONFIG_SUNRPC_BACKCHANNEL)
719/**
720 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
721 * rpc_execute against it
722 * @req: RPC request
723 * @tk_ops: RPC call ops
724 */
725struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
726 const struct rpc_call_ops *tk_ops)
727{
728 struct rpc_task *task;
729 struct xdr_buf *xbufp = &req->rq_snd_buf;
730 struct rpc_task_setup task_setup_data = {
731 .callback_ops = tk_ops,
732 };
733
734 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
735 /*
736 * Create an rpc_task to send the data
737 */
738 task = rpc_new_task(&task_setup_data);
739 if (IS_ERR(task)) {
740 xprt_free_bc_request(req);
741 goto out;
742 }
743 task->tk_rqstp = req;
744
745 /*
746 * Set up the xdr_buf length.
747 * This also indicates that the buffer is XDR encoded already.
748 */
749 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
750 xbufp->tail[0].iov_len;
751
752 task->tk_action = call_bc_transmit;
753 atomic_inc(&task->tk_count);
754 BUG_ON(atomic_read(&task->tk_count) != 2);
755 rpc_execute(task);
756
757out:
758 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
759 return task;
760}
761#endif /* CONFIG_SUNRPC_BACKCHANNEL */
762
763void
764rpc_call_start(struct rpc_task *task)
765{
766 task->tk_action = call_start;
767}
768EXPORT_SYMBOL_GPL(rpc_call_start);
769
770/**
771 * rpc_peeraddr - extract remote peer address from clnt's xprt
772 * @clnt: RPC client structure
773 * @buf: target buffer
774 * @bufsize: length of target buffer
775 *
776 * Returns the number of bytes that are actually in the stored address.
777 */
778size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
779{
780 size_t bytes;
781 struct rpc_xprt *xprt = clnt->cl_xprt;
782
783 bytes = sizeof(xprt->addr);
784 if (bytes > bufsize)
785 bytes = bufsize;
786 memcpy(buf, &clnt->cl_xprt->addr, bytes);
787 return xprt->addrlen;
788}
789EXPORT_SYMBOL_GPL(rpc_peeraddr);
790
791/**
792 * rpc_peeraddr2str - return remote peer address in printable format
793 * @clnt: RPC client structure
794 * @format: address format
795 *
796 */
797const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
798 enum rpc_display_format_t format)
799{
800 struct rpc_xprt *xprt = clnt->cl_xprt;
801
802 if (xprt->address_strings[format] != NULL)
803 return xprt->address_strings[format];
804 else
805 return "unprintable";
806}
807EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
808
809void
810rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
811{
812 struct rpc_xprt *xprt = clnt->cl_xprt;
813 if (xprt->ops->set_buffer_size)
814 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
815}
816EXPORT_SYMBOL_GPL(rpc_setbufsize);
817
818/*
819 * Return size of largest payload RPC client can support, in bytes
820 *
821 * For stream transports, this is one RPC record fragment (see RFC
822 * 1831), as we don't support multi-record requests yet. For datagram
823 * transports, this is the size of an IP packet minus the IP, UDP, and
824 * RPC header sizes.
825 */
826size_t rpc_max_payload(struct rpc_clnt *clnt)
827{
828 return clnt->cl_xprt->max_payload;
829}
830EXPORT_SYMBOL_GPL(rpc_max_payload);
831
832/**
833 * rpc_force_rebind - force transport to check that remote port is unchanged
834 * @clnt: client to rebind
835 *
836 */
837void rpc_force_rebind(struct rpc_clnt *clnt)
838{
839 if (clnt->cl_autobind)
840 xprt_clear_bound(clnt->cl_xprt);
841}
842EXPORT_SYMBOL_GPL(rpc_force_rebind);
843
844/*
845 * Restart an (async) RPC call from the call_prepare state.
846 * Usually called from within the exit handler.
847 */
848int
849rpc_restart_call_prepare(struct rpc_task *task)
850{
851 if (RPC_ASSASSINATED(task))
852 return 0;
853 task->tk_action = rpc_prepare_task;
854 return 1;
855}
856EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
857
858/*
859 * Restart an (async) RPC call. Usually called from within the
860 * exit handler.
861 */
862int
863rpc_restart_call(struct rpc_task *task)
864{
865 if (RPC_ASSASSINATED(task))
866 return 0;
867 task->tk_action = call_start;
868 return 1;
869}
870EXPORT_SYMBOL_GPL(rpc_restart_call);
871
872#ifdef RPC_DEBUG
873static const char *rpc_proc_name(const struct rpc_task *task)
874{
875 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
876
877 if (proc) {
878 if (proc->p_name)
879 return proc->p_name;
880 else
881 return "NULL";
882 } else
883 return "no proc";
884}
885#endif
886
887/*
888 * 0. Initial state
889 *
890 * Other FSM states can be visited zero or more times, but
891 * this state is visited exactly once for each RPC.
892 */
893static void
894call_start(struct rpc_task *task)
895{
896 struct rpc_clnt *clnt = task->tk_client;
897
898 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
899 clnt->cl_protname, clnt->cl_vers,
900 rpc_proc_name(task),
901 (RPC_IS_ASYNC(task) ? "async" : "sync"));
902
903 /* Increment call count */
904 task->tk_msg.rpc_proc->p_count++;
905 clnt->cl_stats->rpccnt++;
906 task->tk_action = call_reserve;
907}
908
909/*
910 * 1. Reserve an RPC call slot
911 */
912static void
913call_reserve(struct rpc_task *task)
914{
915 dprint_status(task);
916
917 task->tk_status = 0;
918 task->tk_action = call_reserveresult;
919 xprt_reserve(task);
920}
921
922/*
923 * 1b. Grok the result of xprt_reserve()
924 */
925static void
926call_reserveresult(struct rpc_task *task)
927{
928 int status = task->tk_status;
929
930 dprint_status(task);
931
932 /*
933 * After a call to xprt_reserve(), we must have either
934 * a request slot or else an error status.
935 */
936 task->tk_status = 0;
937 if (status >= 0) {
938 if (task->tk_rqstp) {
939 task->tk_action = call_refresh;
940 return;
941 }
942
943 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
944 __func__, status);
945 rpc_exit(task, -EIO);
946 return;
947 }
948
949 /*
950 * Even though there was an error, we may have acquired
951 * a request slot somehow. Make sure not to leak it.
952 */
953 if (task->tk_rqstp) {
954 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
955 __func__, status);
956 xprt_release(task);
957 }
958
959 switch (status) {
960 case -EAGAIN: /* woken up; retry */
961 task->tk_action = call_reserve;
962 return;
963 case -EIO: /* probably a shutdown */
964 break;
965 default:
966 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
967 __func__, status);
968 break;
969 }
970 rpc_exit(task, status);
971}
972
973/*
974 * 2. Bind and/or refresh the credentials
975 */
976static void
977call_refresh(struct rpc_task *task)
978{
979 dprint_status(task);
980
981 task->tk_action = call_refreshresult;
982 task->tk_status = 0;
983 task->tk_client->cl_stats->rpcauthrefresh++;
984 rpcauth_refreshcred(task);
985}
986
987/*
988 * 2a. Process the results of a credential refresh
989 */
990static void
991call_refreshresult(struct rpc_task *task)
992{
993 int status = task->tk_status;
994
995 dprint_status(task);
996
997 task->tk_status = 0;
998 task->tk_action = call_refresh;
999 switch (status) {
1000 case 0:
1001 if (rpcauth_uptodatecred(task))
1002 task->tk_action = call_allocate;
1003 return;
1004 case -ETIMEDOUT:
1005 rpc_delay(task, 3*HZ);
1006 case -EAGAIN:
1007 status = -EACCES;
1008 if (!task->tk_cred_retry)
1009 break;
1010 task->tk_cred_retry--;
1011 dprintk("RPC: %5u %s: retry refresh creds\n",
1012 task->tk_pid, __func__);
1013 return;
1014 }
1015 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1016 task->tk_pid, __func__, status);
1017 rpc_exit(task, status);
1018}
1019
1020/*
1021 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1022 * (Note: buffer memory is freed in xprt_release).
1023 */
1024static void
1025call_allocate(struct rpc_task *task)
1026{
1027 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1028 struct rpc_rqst *req = task->tk_rqstp;
1029 struct rpc_xprt *xprt = task->tk_xprt;
1030 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1031
1032 dprint_status(task);
1033
1034 task->tk_status = 0;
1035 task->tk_action = call_bind;
1036
1037 if (req->rq_buffer)
1038 return;
1039
1040 if (proc->p_proc != 0) {
1041 BUG_ON(proc->p_arglen == 0);
1042 if (proc->p_decode != NULL)
1043 BUG_ON(proc->p_replen == 0);
1044 }
1045
1046 /*
1047 * Calculate the size (in quads) of the RPC call
1048 * and reply headers, and convert both values
1049 * to byte sizes.
1050 */
1051 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1052 req->rq_callsize <<= 2;
1053 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1054 req->rq_rcvsize <<= 2;
1055
1056 req->rq_buffer = xprt->ops->buf_alloc(task,
1057 req->rq_callsize + req->rq_rcvsize);
1058 if (req->rq_buffer != NULL)
1059 return;
1060
1061 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1062
1063 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1064 task->tk_action = call_allocate;
1065 rpc_delay(task, HZ>>4);
1066 return;
1067 }
1068
1069 rpc_exit(task, -ERESTARTSYS);
1070}
1071
1072static inline int
1073rpc_task_need_encode(struct rpc_task *task)
1074{
1075 return task->tk_rqstp->rq_snd_buf.len == 0;
1076}
1077
1078static inline void
1079rpc_task_force_reencode(struct rpc_task *task)
1080{
1081 task->tk_rqstp->rq_snd_buf.len = 0;
1082 task->tk_rqstp->rq_bytes_sent = 0;
1083}
1084
1085static inline void
1086rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1087{
1088 buf->head[0].iov_base = start;
1089 buf->head[0].iov_len = len;
1090 buf->tail[0].iov_len = 0;
1091 buf->page_len = 0;
1092 buf->flags = 0;
1093 buf->len = 0;
1094 buf->buflen = len;
1095}
1096
1097/*
1098 * 3. Encode arguments of an RPC call
1099 */
1100static void
1101rpc_xdr_encode(struct rpc_task *task)
1102{
1103 struct rpc_rqst *req = task->tk_rqstp;
1104 kxdreproc_t encode;
1105 __be32 *p;
1106
1107 dprint_status(task);
1108
1109 rpc_xdr_buf_init(&req->rq_snd_buf,
1110 req->rq_buffer,
1111 req->rq_callsize);
1112 rpc_xdr_buf_init(&req->rq_rcv_buf,
1113 (char *)req->rq_buffer + req->rq_callsize,
1114 req->rq_rcvsize);
1115
1116 p = rpc_encode_header(task);
1117 if (p == NULL) {
1118 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1119 rpc_exit(task, -EIO);
1120 return;
1121 }
1122
1123 encode = task->tk_msg.rpc_proc->p_encode;
1124 if (encode == NULL)
1125 return;
1126
1127 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1128 task->tk_msg.rpc_argp);
1129}
1130
1131/*
1132 * 4. Get the server port number if not yet set
1133 */
1134static void
1135call_bind(struct rpc_task *task)
1136{
1137 struct rpc_xprt *xprt = task->tk_xprt;
1138
1139 dprint_status(task);
1140
1141 task->tk_action = call_connect;
1142 if (!xprt_bound(xprt)) {
1143 task->tk_action = call_bind_status;
1144 task->tk_timeout = xprt->bind_timeout;
1145 xprt->ops->rpcbind(task);
1146 }
1147}
1148
1149/*
1150 * 4a. Sort out bind result
1151 */
1152static void
1153call_bind_status(struct rpc_task *task)
1154{
1155 int status = -EIO;
1156
1157 if (task->tk_status >= 0) {
1158 dprint_status(task);
1159 task->tk_status = 0;
1160 task->tk_action = call_connect;
1161 return;
1162 }
1163
1164 switch (task->tk_status) {
1165 case -ENOMEM:
1166 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1167 rpc_delay(task, HZ >> 2);
1168 goto retry_timeout;
1169 case -EACCES:
1170 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1171 "unavailable\n", task->tk_pid);
1172 /* fail immediately if this is an RPC ping */
1173 if (task->tk_msg.rpc_proc->p_proc == 0) {
1174 status = -EOPNOTSUPP;
1175 break;
1176 }
1177 if (task->tk_rebind_retry == 0)
1178 break;
1179 task->tk_rebind_retry--;
1180 rpc_delay(task, 3*HZ);
1181 goto retry_timeout;
1182 case -ETIMEDOUT:
1183 dprintk("RPC: %5u rpcbind request timed out\n",
1184 task->tk_pid);
1185 goto retry_timeout;
1186 case -EPFNOSUPPORT:
1187 /* server doesn't support any rpcbind version we know of */
1188 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1189 task->tk_pid);
1190 break;
1191 case -EPROTONOSUPPORT:
1192 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1193 task->tk_pid);
1194 task->tk_status = 0;
1195 task->tk_action = call_bind;
1196 return;
1197 case -ECONNREFUSED: /* connection problems */
1198 case -ECONNRESET:
1199 case -ENOTCONN:
1200 case -EHOSTDOWN:
1201 case -EHOSTUNREACH:
1202 case -ENETUNREACH:
1203 case -EPIPE:
1204 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1205 task->tk_pid, task->tk_status);
1206 if (!RPC_IS_SOFTCONN(task)) {
1207 rpc_delay(task, 5*HZ);
1208 goto retry_timeout;
1209 }
1210 status = task->tk_status;
1211 break;
1212 default:
1213 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1214 task->tk_pid, -task->tk_status);
1215 }
1216
1217 rpc_exit(task, status);
1218 return;
1219
1220retry_timeout:
1221 task->tk_action = call_timeout;
1222}
1223
1224/*
1225 * 4b. Connect to the RPC server
1226 */
1227static void
1228call_connect(struct rpc_task *task)
1229{
1230 struct rpc_xprt *xprt = task->tk_xprt;
1231
1232 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1233 task->tk_pid, xprt,
1234 (xprt_connected(xprt) ? "is" : "is not"));
1235
1236 task->tk_action = call_transmit;
1237 if (!xprt_connected(xprt)) {
1238 task->tk_action = call_connect_status;
1239 if (task->tk_status < 0)
1240 return;
1241 xprt_connect(task);
1242 }
1243}
1244
1245/*
1246 * 4c. Sort out connect result
1247 */
1248static void
1249call_connect_status(struct rpc_task *task)
1250{
1251 struct rpc_clnt *clnt = task->tk_client;
1252 int status = task->tk_status;
1253
1254 dprint_status(task);
1255
1256 task->tk_status = 0;
1257 if (status >= 0 || status == -EAGAIN) {
1258 clnt->cl_stats->netreconn++;
1259 task->tk_action = call_transmit;
1260 return;
1261 }
1262
1263 switch (status) {
1264 /* if soft mounted, test if we've timed out */
1265 case -ETIMEDOUT:
1266 task->tk_action = call_timeout;
1267 break;
1268 default:
1269 rpc_exit(task, -EIO);
1270 }
1271}
1272
1273/*
1274 * 5. Transmit the RPC request, and wait for reply
1275 */
1276static void
1277call_transmit(struct rpc_task *task)
1278{
1279 dprint_status(task);
1280
1281 task->tk_action = call_status;
1282 if (task->tk_status < 0)
1283 return;
1284 task->tk_status = xprt_prepare_transmit(task);
1285 if (task->tk_status != 0)
1286 return;
1287 task->tk_action = call_transmit_status;
1288 /* Encode here so that rpcsec_gss can use correct sequence number. */
1289 if (rpc_task_need_encode(task)) {
1290 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1291 rpc_xdr_encode(task);
1292 /* Did the encode result in an error condition? */
1293 if (task->tk_status != 0) {
1294 /* Was the error nonfatal? */
1295 if (task->tk_status == -EAGAIN)
1296 rpc_delay(task, HZ >> 4);
1297 else
1298 rpc_exit(task, task->tk_status);
1299 return;
1300 }
1301 }
1302 xprt_transmit(task);
1303 if (task->tk_status < 0)
1304 return;
1305 /*
1306 * On success, ensure that we call xprt_end_transmit() before sleeping
1307 * in order to allow access to the socket to other RPC requests.
1308 */
1309 call_transmit_status(task);
1310 if (rpc_reply_expected(task))
1311 return;
1312 task->tk_action = rpc_exit_task;
1313 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1314}
1315
1316/*
1317 * 5a. Handle cleanup after a transmission
1318 */
1319static void
1320call_transmit_status(struct rpc_task *task)
1321{
1322 task->tk_action = call_status;
1323
1324 /*
1325 * Common case: success. Force the compiler to put this
1326 * test first.
1327 */
1328 if (task->tk_status == 0) {
1329 xprt_end_transmit(task);
1330 rpc_task_force_reencode(task);
1331 return;
1332 }
1333
1334 switch (task->tk_status) {
1335 case -EAGAIN:
1336 break;
1337 default:
1338 dprint_status(task);
1339 xprt_end_transmit(task);
1340 rpc_task_force_reencode(task);
1341 break;
1342 /*
1343 * Special cases: if we've been waiting on the
1344 * socket's write_space() callback, or if the
1345 * socket just returned a connection error,
1346 * then hold onto the transport lock.
1347 */
1348 case -ECONNREFUSED:
1349 case -EHOSTDOWN:
1350 case -EHOSTUNREACH:
1351 case -ENETUNREACH:
1352 if (RPC_IS_SOFTCONN(task)) {
1353 xprt_end_transmit(task);
1354 rpc_exit(task, task->tk_status);
1355 break;
1356 }
1357 case -ECONNRESET:
1358 case -ENOTCONN:
1359 case -EPIPE:
1360 rpc_task_force_reencode(task);
1361 }
1362}
1363
1364#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1365/*
1366 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1367 * addition, disconnect on connectivity errors.
1368 */
1369static void
1370call_bc_transmit(struct rpc_task *task)
1371{
1372 struct rpc_rqst *req = task->tk_rqstp;
1373
1374 BUG_ON(task->tk_status != 0);
1375 task->tk_status = xprt_prepare_transmit(task);
1376 if (task->tk_status == -EAGAIN) {
1377 /*
1378 * Could not reserve the transport. Try again after the
1379 * transport is released.
1380 */
1381 task->tk_status = 0;
1382 task->tk_action = call_bc_transmit;
1383 return;
1384 }
1385
1386 task->tk_action = rpc_exit_task;
1387 if (task->tk_status < 0) {
1388 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1389 "error: %d\n", task->tk_status);
1390 return;
1391 }
1392
1393 xprt_transmit(task);
1394 xprt_end_transmit(task);
1395 dprint_status(task);
1396 switch (task->tk_status) {
1397 case 0:
1398 /* Success */
1399 break;
1400 case -EHOSTDOWN:
1401 case -EHOSTUNREACH:
1402 case -ENETUNREACH:
1403 case -ETIMEDOUT:
1404 /*
1405 * Problem reaching the server. Disconnect and let the
1406 * forechannel reestablish the connection. The server will
1407 * have to retransmit the backchannel request and we'll
1408 * reprocess it. Since these ops are idempotent, there's no
1409 * need to cache our reply at this time.
1410 */
1411 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1412 "error: %d\n", task->tk_status);
1413 xprt_conditional_disconnect(task->tk_xprt,
1414 req->rq_connect_cookie);
1415 break;
1416 default:
1417 /*
1418 * We were unable to reply and will have to drop the
1419 * request. The server should reconnect and retransmit.
1420 */
1421 BUG_ON(task->tk_status == -EAGAIN);
1422 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1423 "error: %d\n", task->tk_status);
1424 break;
1425 }
1426 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1427}
1428#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1429
1430/*
1431 * 6. Sort out the RPC call status
1432 */
1433static void
1434call_status(struct rpc_task *task)
1435{
1436 struct rpc_clnt *clnt = task->tk_client;
1437 struct rpc_rqst *req = task->tk_rqstp;
1438 int status;
1439
1440 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1441 task->tk_status = req->rq_reply_bytes_recvd;
1442
1443 dprint_status(task);
1444
1445 status = task->tk_status;
1446 if (status >= 0) {
1447 task->tk_action = call_decode;
1448 return;
1449 }
1450
1451 task->tk_status = 0;
1452 switch(status) {
1453 case -EHOSTDOWN:
1454 case -EHOSTUNREACH:
1455 case -ENETUNREACH:
1456 /*
1457 * Delay any retries for 3 seconds, then handle as if it
1458 * were a timeout.
1459 */
1460 rpc_delay(task, 3*HZ);
1461 case -ETIMEDOUT:
1462 task->tk_action = call_timeout;
1463 if (task->tk_client->cl_discrtry)
1464 xprt_conditional_disconnect(task->tk_xprt,
1465 req->rq_connect_cookie);
1466 break;
1467 case -ECONNRESET:
1468 case -ECONNREFUSED:
1469 rpc_force_rebind(clnt);
1470 rpc_delay(task, 3*HZ);
1471 case -EPIPE:
1472 case -ENOTCONN:
1473 task->tk_action = call_bind;
1474 break;
1475 case -EAGAIN:
1476 task->tk_action = call_transmit;
1477 break;
1478 case -EIO:
1479 /* shutdown or soft timeout */
1480 rpc_exit(task, status);
1481 break;
1482 default:
1483 if (clnt->cl_chatty)
1484 printk("%s: RPC call returned error %d\n",
1485 clnt->cl_protname, -status);
1486 rpc_exit(task, status);
1487 }
1488}
1489
1490/*
1491 * 6a. Handle RPC timeout
1492 * We do not release the request slot, so we keep using the
1493 * same XID for all retransmits.
1494 */
1495static void
1496call_timeout(struct rpc_task *task)
1497{
1498 struct rpc_clnt *clnt = task->tk_client;
1499
1500 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1501 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1502 goto retry;
1503 }
1504
1505 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1506 task->tk_timeouts++;
1507
1508 if (RPC_IS_SOFTCONN(task)) {
1509 rpc_exit(task, -ETIMEDOUT);
1510 return;
1511 }
1512 if (RPC_IS_SOFT(task)) {
1513 if (clnt->cl_chatty)
1514 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1515 clnt->cl_protname, clnt->cl_server);
1516 if (task->tk_flags & RPC_TASK_TIMEOUT)
1517 rpc_exit(task, -ETIMEDOUT);
1518 else
1519 rpc_exit(task, -EIO);
1520 return;
1521 }
1522
1523 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1524 task->tk_flags |= RPC_CALL_MAJORSEEN;
1525 if (clnt->cl_chatty)
1526 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1527 clnt->cl_protname, clnt->cl_server);
1528 }
1529 rpc_force_rebind(clnt);
1530 /*
1531 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1532 * event? RFC2203 requires the server to drop all such requests.
1533 */
1534 rpcauth_invalcred(task);
1535
1536retry:
1537 clnt->cl_stats->rpcretrans++;
1538 task->tk_action = call_bind;
1539 task->tk_status = 0;
1540}
1541
1542/*
1543 * 7. Decode the RPC reply
1544 */
1545static void
1546call_decode(struct rpc_task *task)
1547{
1548 struct rpc_clnt *clnt = task->tk_client;
1549 struct rpc_rqst *req = task->tk_rqstp;
1550 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
1551 __be32 *p;
1552
1553 dprint_status(task);
1554
1555 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1556 if (clnt->cl_chatty)
1557 printk(KERN_NOTICE "%s: server %s OK\n",
1558 clnt->cl_protname, clnt->cl_server);
1559 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1560 }
1561
1562 /*
1563 * Ensure that we see all writes made by xprt_complete_rqst()
1564 * before it changed req->rq_reply_bytes_recvd.
1565 */
1566 smp_rmb();
1567 req->rq_rcv_buf.len = req->rq_private_buf.len;
1568
1569 /* Check that the softirq receive buffer is valid */
1570 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1571 sizeof(req->rq_rcv_buf)) != 0);
1572
1573 if (req->rq_rcv_buf.len < 12) {
1574 if (!RPC_IS_SOFT(task)) {
1575 task->tk_action = call_bind;
1576 clnt->cl_stats->rpcretrans++;
1577 goto out_retry;
1578 }
1579 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1580 clnt->cl_protname, task->tk_status);
1581 task->tk_action = call_timeout;
1582 goto out_retry;
1583 }
1584
1585 p = rpc_verify_header(task);
1586 if (IS_ERR(p)) {
1587 if (p == ERR_PTR(-EAGAIN))
1588 goto out_retry;
1589 return;
1590 }
1591
1592 task->tk_action = rpc_exit_task;
1593
1594 if (decode) {
1595 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1596 task->tk_msg.rpc_resp);
1597 }
1598 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1599 task->tk_status);
1600 return;
1601out_retry:
1602 task->tk_status = 0;
1603 /* Note: rpc_verify_header() may have freed the RPC slot */
1604 if (task->tk_rqstp == req) {
1605 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
1606 if (task->tk_client->cl_discrtry)
1607 xprt_conditional_disconnect(task->tk_xprt,
1608 req->rq_connect_cookie);
1609 }
1610}
1611
1612static __be32 *
1613rpc_encode_header(struct rpc_task *task)
1614{
1615 struct rpc_clnt *clnt = task->tk_client;
1616 struct rpc_rqst *req = task->tk_rqstp;
1617 __be32 *p = req->rq_svec[0].iov_base;
1618
1619 /* FIXME: check buffer size? */
1620
1621 p = xprt_skip_transport_header(task->tk_xprt, p);
1622 *p++ = req->rq_xid; /* XID */
1623 *p++ = htonl(RPC_CALL); /* CALL */
1624 *p++ = htonl(RPC_VERSION); /* RPC version */
1625 *p++ = htonl(clnt->cl_prog); /* program number */
1626 *p++ = htonl(clnt->cl_vers); /* program version */
1627 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1628 p = rpcauth_marshcred(task, p);
1629 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1630 return p;
1631}
1632
1633static __be32 *
1634rpc_verify_header(struct rpc_task *task)
1635{
1636 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1637 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1638 __be32 *p = iov->iov_base;
1639 u32 n;
1640 int error = -EACCES;
1641
1642 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1643 /* RFC-1014 says that the representation of XDR data must be a
1644 * multiple of four bytes
1645 * - if it isn't pointer subtraction in the NFS client may give
1646 * undefined results
1647 */
1648 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1649 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
1650 task->tk_rqstp->rq_rcv_buf.len);
1651 goto out_eio;
1652 }
1653 if ((len -= 3) < 0)
1654 goto out_overflow;
1655
1656 p += 1; /* skip XID */
1657 if ((n = ntohl(*p++)) != RPC_REPLY) {
1658 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1659 task->tk_pid, __func__, n);
1660 goto out_garbage;
1661 }
1662
1663 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1664 if (--len < 0)
1665 goto out_overflow;
1666 switch ((n = ntohl(*p++))) {
1667 case RPC_AUTH_ERROR:
1668 break;
1669 case RPC_MISMATCH:
1670 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
1671 task->tk_pid, __func__);
1672 error = -EPROTONOSUPPORT;
1673 goto out_err;
1674 default:
1675 dprintk("RPC: %5u %s: RPC call rejected, "
1676 "unknown error: %x\n",
1677 task->tk_pid, __func__, n);
1678 goto out_eio;
1679 }
1680 if (--len < 0)
1681 goto out_overflow;
1682 switch ((n = ntohl(*p++))) {
1683 case RPC_AUTH_REJECTEDCRED:
1684 case RPC_AUTH_REJECTEDVERF:
1685 case RPCSEC_GSS_CREDPROBLEM:
1686 case RPCSEC_GSS_CTXPROBLEM:
1687 if (!task->tk_cred_retry)
1688 break;
1689 task->tk_cred_retry--;
1690 dprintk("RPC: %5u %s: retry stale creds\n",
1691 task->tk_pid, __func__);
1692 rpcauth_invalcred(task);
1693 /* Ensure we obtain a new XID! */
1694 xprt_release(task);
1695 task->tk_action = call_reserve;
1696 goto out_retry;
1697 case RPC_AUTH_BADCRED:
1698 case RPC_AUTH_BADVERF:
1699 /* possibly garbled cred/verf? */
1700 if (!task->tk_garb_retry)
1701 break;
1702 task->tk_garb_retry--;
1703 dprintk("RPC: %5u %s: retry garbled creds\n",
1704 task->tk_pid, __func__);
1705 task->tk_action = call_bind;
1706 goto out_retry;
1707 case RPC_AUTH_TOOWEAK:
1708 printk(KERN_NOTICE "RPC: server %s requires stronger "
1709 "authentication.\n", task->tk_client->cl_server);
1710 break;
1711 default:
1712 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1713 task->tk_pid, __func__, n);
1714 error = -EIO;
1715 }
1716 dprintk("RPC: %5u %s: call rejected %d\n",
1717 task->tk_pid, __func__, n);
1718 goto out_err;
1719 }
1720 if (!(p = rpcauth_checkverf(task, p))) {
1721 dprintk("RPC: %5u %s: auth check failed\n",
1722 task->tk_pid, __func__);
1723 goto out_garbage; /* bad verifier, retry */
1724 }
1725 len = p - (__be32 *)iov->iov_base - 1;
1726 if (len < 0)
1727 goto out_overflow;
1728 switch ((n = ntohl(*p++))) {
1729 case RPC_SUCCESS:
1730 return p;
1731 case RPC_PROG_UNAVAIL:
1732 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1733 task->tk_pid, __func__,
1734 (unsigned int)task->tk_client->cl_prog,
1735 task->tk_client->cl_server);
1736 error = -EPFNOSUPPORT;
1737 goto out_err;
1738 case RPC_PROG_MISMATCH:
1739 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1740 "server %s\n", task->tk_pid, __func__,
1741 (unsigned int)task->tk_client->cl_prog,
1742 (unsigned int)task->tk_client->cl_vers,
1743 task->tk_client->cl_server);
1744 error = -EPROTONOSUPPORT;
1745 goto out_err;
1746 case RPC_PROC_UNAVAIL:
1747 dprintk("RPC: %5u %s: proc %s unsupported by program %u, "
1748 "version %u on server %s\n",
1749 task->tk_pid, __func__,
1750 rpc_proc_name(task),
1751 task->tk_client->cl_prog,
1752 task->tk_client->cl_vers,
1753 task->tk_client->cl_server);
1754 error = -EOPNOTSUPP;
1755 goto out_err;
1756 case RPC_GARBAGE_ARGS:
1757 dprintk("RPC: %5u %s: server saw garbage\n",
1758 task->tk_pid, __func__);
1759 break; /* retry */
1760 default:
1761 dprintk("RPC: %5u %s: server accept status: %x\n",
1762 task->tk_pid, __func__, n);
1763 /* Also retry */
1764 }
1765
1766out_garbage:
1767 task->tk_client->cl_stats->rpcgarbage++;
1768 if (task->tk_garb_retry) {
1769 task->tk_garb_retry--;
1770 dprintk("RPC: %5u %s: retrying\n",
1771 task->tk_pid, __func__);
1772 task->tk_action = call_bind;
1773out_retry:
1774 return ERR_PTR(-EAGAIN);
1775 }
1776out_eio:
1777 error = -EIO;
1778out_err:
1779 rpc_exit(task, error);
1780 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1781 __func__, error);
1782 return ERR_PTR(error);
1783out_overflow:
1784 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1785 __func__);
1786 goto out_garbage;
1787}
1788
1789static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
1790{
1791}
1792
1793static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
1794{
1795 return 0;
1796}
1797
1798static struct rpc_procinfo rpcproc_null = {
1799 .p_encode = rpcproc_encode_null,
1800 .p_decode = rpcproc_decode_null,
1801};
1802
1803static int rpc_ping(struct rpc_clnt *clnt)
1804{
1805 struct rpc_message msg = {
1806 .rpc_proc = &rpcproc_null,
1807 };
1808 int err;
1809 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1810 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
1811 put_rpccred(msg.rpc_cred);
1812 return err;
1813}
1814
1815struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1816{
1817 struct rpc_message msg = {
1818 .rpc_proc = &rpcproc_null,
1819 .rpc_cred = cred,
1820 };
1821 struct rpc_task_setup task_setup_data = {
1822 .rpc_client = clnt,
1823 .rpc_message = &msg,
1824 .callback_ops = &rpc_default_ops,
1825 .flags = flags,
1826 };
1827 return rpc_run_task(&task_setup_data);
1828}
1829EXPORT_SYMBOL_GPL(rpc_call_null);
1830
1831#ifdef RPC_DEBUG
1832static void rpc_show_header(void)
1833{
1834 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
1835 "-timeout ---ops--\n");
1836}
1837
1838static void rpc_show_task(const struct rpc_clnt *clnt,
1839 const struct rpc_task *task)
1840{
1841 const char *rpc_waitq = "none";
1842
1843 if (RPC_IS_QUEUED(task))
1844 rpc_waitq = rpc_qname(task->tk_waitqueue);
1845
1846 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
1847 task->tk_pid, task->tk_flags, task->tk_status,
1848 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
1849 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task),
1850 task->tk_action, rpc_waitq);
1851}
1852
1853void rpc_show_tasks(void)
1854{
1855 struct rpc_clnt *clnt;
1856 struct rpc_task *task;
1857 int header = 0;
1858
1859 spin_lock(&rpc_client_lock);
1860 list_for_each_entry(clnt, &all_clients, cl_clients) {
1861 spin_lock(&clnt->cl_lock);
1862 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
1863 if (!header) {
1864 rpc_show_header();
1865 header++;
1866 }
1867 rpc_show_task(clnt, task);
1868 }
1869 spin_unlock(&clnt->cl_lock);
1870 }
1871 spin_unlock(&rpc_client_lock);
1872}
1873#endif