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