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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 "sysfs.h"
45#include "netns.h"
46
47#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
48# define RPCDBG_FACILITY RPCDBG_CALL
49#endif
50
51/*
52 * All RPC clients are linked into this list
53 */
54
55static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
56
57
58static void call_start(struct rpc_task *task);
59static void call_reserve(struct rpc_task *task);
60static void call_reserveresult(struct rpc_task *task);
61static void call_allocate(struct rpc_task *task);
62static void call_encode(struct rpc_task *task);
63static void call_decode(struct rpc_task *task);
64static void call_bind(struct rpc_task *task);
65static void call_bind_status(struct rpc_task *task);
66static void call_transmit(struct rpc_task *task);
67static void call_status(struct rpc_task *task);
68static void call_transmit_status(struct rpc_task *task);
69static void call_refresh(struct rpc_task *task);
70static void call_refreshresult(struct rpc_task *task);
71static void call_connect(struct rpc_task *task);
72static void call_connect_status(struct rpc_task *task);
73
74static int rpc_encode_header(struct rpc_task *task,
75 struct xdr_stream *xdr);
76static int rpc_decode_header(struct rpc_task *task,
77 struct xdr_stream *xdr);
78static int rpc_ping(struct rpc_clnt *clnt);
79static int rpc_ping_noreply(struct rpc_clnt *clnt);
80static void rpc_check_timeout(struct rpc_task *task);
81
82static void rpc_register_client(struct rpc_clnt *clnt)
83{
84 struct net *net = rpc_net_ns(clnt);
85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
86
87 spin_lock(&sn->rpc_client_lock);
88 list_add(&clnt->cl_clients, &sn->all_clients);
89 spin_unlock(&sn->rpc_client_lock);
90}
91
92static void rpc_unregister_client(struct rpc_clnt *clnt)
93{
94 struct net *net = rpc_net_ns(clnt);
95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
96
97 spin_lock(&sn->rpc_client_lock);
98 list_del(&clnt->cl_clients);
99 spin_unlock(&sn->rpc_client_lock);
100}
101
102static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103{
104 rpc_remove_client_dir(clnt);
105}
106
107static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
108{
109 struct net *net = rpc_net_ns(clnt);
110 struct super_block *pipefs_sb;
111
112 pipefs_sb = rpc_get_sb_net(net);
113 if (pipefs_sb) {
114 if (pipefs_sb == clnt->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 clnt->pipefs_sb = pipefs_sb;
156
157 if (clnt->cl_program->pipe_dir_name != NULL) {
158 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
159 if (IS_ERR(dentry))
160 return PTR_ERR(dentry);
161 }
162 return 0;
163}
164
165static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
166{
167 if (clnt->cl_program->pipe_dir_name == NULL)
168 return 1;
169
170 switch (event) {
171 case RPC_PIPEFS_MOUNT:
172 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
173 return 1;
174 if (refcount_read(&clnt->cl_count) == 0)
175 return 1;
176 break;
177 case RPC_PIPEFS_UMOUNT:
178 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
179 return 1;
180 break;
181 }
182 return 0;
183}
184
185static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
186 struct super_block *sb)
187{
188 struct dentry *dentry;
189
190 switch (event) {
191 case RPC_PIPEFS_MOUNT:
192 dentry = rpc_setup_pipedir_sb(sb, clnt);
193 if (!dentry)
194 return -ENOENT;
195 if (IS_ERR(dentry))
196 return PTR_ERR(dentry);
197 break;
198 case RPC_PIPEFS_UMOUNT:
199 __rpc_clnt_remove_pipedir(clnt);
200 break;
201 default:
202 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
203 return -ENOTSUPP;
204 }
205 return 0;
206}
207
208static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
209 struct super_block *sb)
210{
211 int error = 0;
212
213 for (;; clnt = clnt->cl_parent) {
214 if (!rpc_clnt_skip_event(clnt, event))
215 error = __rpc_clnt_handle_event(clnt, event, sb);
216 if (error || clnt == clnt->cl_parent)
217 break;
218 }
219 return error;
220}
221
222static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
223{
224 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
225 struct rpc_clnt *clnt;
226
227 spin_lock(&sn->rpc_client_lock);
228 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
229 if (rpc_clnt_skip_event(clnt, event))
230 continue;
231 spin_unlock(&sn->rpc_client_lock);
232 return clnt;
233 }
234 spin_unlock(&sn->rpc_client_lock);
235 return NULL;
236}
237
238static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
239 void *ptr)
240{
241 struct super_block *sb = ptr;
242 struct rpc_clnt *clnt;
243 int error = 0;
244
245 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
246 error = __rpc_pipefs_event(clnt, event, sb);
247 if (error)
248 break;
249 }
250 return error;
251}
252
253static struct notifier_block rpc_clients_block = {
254 .notifier_call = rpc_pipefs_event,
255 .priority = SUNRPC_PIPEFS_RPC_PRIO,
256};
257
258int rpc_clients_notifier_register(void)
259{
260 return rpc_pipefs_notifier_register(&rpc_clients_block);
261}
262
263void rpc_clients_notifier_unregister(void)
264{
265 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
266}
267
268static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
269 struct rpc_xprt *xprt,
270 const struct rpc_timeout *timeout)
271{
272 struct rpc_xprt *old;
273
274 spin_lock(&clnt->cl_lock);
275 old = rcu_dereference_protected(clnt->cl_xprt,
276 lockdep_is_held(&clnt->cl_lock));
277
278 if (!xprt_bound(xprt))
279 clnt->cl_autobind = 1;
280
281 clnt->cl_timeout = timeout;
282 rcu_assign_pointer(clnt->cl_xprt, xprt);
283 spin_unlock(&clnt->cl_lock);
284
285 return old;
286}
287
288static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
289{
290 ssize_t copied;
291
292 copied = strscpy(clnt->cl_nodename,
293 nodename, sizeof(clnt->cl_nodename));
294
295 clnt->cl_nodelen = copied < 0
296 ? sizeof(clnt->cl_nodename) - 1
297 : copied;
298}
299
300static int rpc_client_register(struct rpc_clnt *clnt,
301 rpc_authflavor_t pseudoflavor,
302 const char *client_name)
303{
304 struct rpc_auth_create_args auth_args = {
305 .pseudoflavor = pseudoflavor,
306 .target_name = client_name,
307 };
308 struct rpc_auth *auth;
309 struct net *net = rpc_net_ns(clnt);
310 struct super_block *pipefs_sb;
311 int err;
312
313 rpc_clnt_debugfs_register(clnt);
314
315 pipefs_sb = rpc_get_sb_net(net);
316 if (pipefs_sb) {
317 err = rpc_setup_pipedir(pipefs_sb, clnt);
318 if (err)
319 goto out;
320 }
321
322 rpc_register_client(clnt);
323 if (pipefs_sb)
324 rpc_put_sb_net(net);
325
326 auth = rpcauth_create(&auth_args, clnt);
327 if (IS_ERR(auth)) {
328 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
329 pseudoflavor);
330 err = PTR_ERR(auth);
331 goto err_auth;
332 }
333 return 0;
334err_auth:
335 pipefs_sb = rpc_get_sb_net(net);
336 rpc_unregister_client(clnt);
337 __rpc_clnt_remove_pipedir(clnt);
338out:
339 if (pipefs_sb)
340 rpc_put_sb_net(net);
341 rpc_sysfs_client_destroy(clnt);
342 rpc_clnt_debugfs_unregister(clnt);
343 return err;
344}
345
346static DEFINE_IDA(rpc_clids);
347
348void rpc_cleanup_clids(void)
349{
350 ida_destroy(&rpc_clids);
351}
352
353static int rpc_alloc_clid(struct rpc_clnt *clnt)
354{
355 int clid;
356
357 clid = ida_alloc(&rpc_clids, GFP_KERNEL);
358 if (clid < 0)
359 return clid;
360 clnt->cl_clid = clid;
361 return 0;
362}
363
364static void rpc_free_clid(struct rpc_clnt *clnt)
365{
366 ida_free(&rpc_clids, clnt->cl_clid);
367}
368
369static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
370 struct rpc_xprt_switch *xps,
371 struct rpc_xprt *xprt,
372 struct rpc_clnt *parent)
373{
374 const struct rpc_program *program = args->program;
375 const struct rpc_version *version;
376 struct rpc_clnt *clnt = NULL;
377 const struct rpc_timeout *timeout;
378 const char *nodename = args->nodename;
379 int err;
380
381 err = rpciod_up();
382 if (err)
383 goto out_no_rpciod;
384
385 err = -EINVAL;
386 if (args->version >= program->nrvers)
387 goto out_err;
388 version = program->version[args->version];
389 if (version == NULL)
390 goto out_err;
391
392 err = -ENOMEM;
393 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
394 if (!clnt)
395 goto out_err;
396 clnt->cl_parent = parent ? : clnt;
397 clnt->cl_xprtsec = args->xprtsec;
398
399 err = rpc_alloc_clid(clnt);
400 if (err)
401 goto out_no_clid;
402
403 clnt->cl_cred = get_cred(args->cred);
404 clnt->cl_procinfo = version->procs;
405 clnt->cl_maxproc = version->nrprocs;
406 clnt->cl_prog = args->prognumber ? : program->number;
407 clnt->cl_vers = version->number;
408 clnt->cl_stats = program->stats;
409 clnt->cl_metrics = rpc_alloc_iostats(clnt);
410 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
411 err = -ENOMEM;
412 if (clnt->cl_metrics == NULL)
413 goto out_no_stats;
414 clnt->cl_program = program;
415 INIT_LIST_HEAD(&clnt->cl_tasks);
416 spin_lock_init(&clnt->cl_lock);
417
418 timeout = xprt->timeout;
419 if (args->timeout != NULL) {
420 memcpy(&clnt->cl_timeout_default, args->timeout,
421 sizeof(clnt->cl_timeout_default));
422 timeout = &clnt->cl_timeout_default;
423 }
424
425 rpc_clnt_set_transport(clnt, xprt, timeout);
426 xprt->main = true;
427 xprt_iter_init(&clnt->cl_xpi, xps);
428 xprt_switch_put(xps);
429
430 clnt->cl_rtt = &clnt->cl_rtt_default;
431 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
432
433 refcount_set(&clnt->cl_count, 1);
434
435 if (nodename == NULL)
436 nodename = utsname()->nodename;
437 /* save the nodename */
438 rpc_clnt_set_nodename(clnt, nodename);
439
440 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
441 err = rpc_client_register(clnt, args->authflavor, args->client_name);
442 if (err)
443 goto out_no_path;
444 if (parent)
445 refcount_inc(&parent->cl_count);
446
447 trace_rpc_clnt_new(clnt, xprt, args);
448 return clnt;
449
450out_no_path:
451 rpc_free_iostats(clnt->cl_metrics);
452out_no_stats:
453 put_cred(clnt->cl_cred);
454 rpc_free_clid(clnt);
455out_no_clid:
456 kfree(clnt);
457out_err:
458 rpciod_down();
459out_no_rpciod:
460 xprt_switch_put(xps);
461 xprt_put(xprt);
462 trace_rpc_clnt_new_err(program->name, args->servername, err);
463 return ERR_PTR(err);
464}
465
466static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
467 struct rpc_xprt *xprt)
468{
469 struct rpc_clnt *clnt = NULL;
470 struct rpc_xprt_switch *xps;
471
472 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
473 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
474 xps = args->bc_xprt->xpt_bc_xps;
475 xprt_switch_get(xps);
476 } else {
477 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
478 if (xps == NULL) {
479 xprt_put(xprt);
480 return ERR_PTR(-ENOMEM);
481 }
482 if (xprt->bc_xprt) {
483 xprt_switch_get(xps);
484 xprt->bc_xprt->xpt_bc_xps = xps;
485 }
486 }
487 clnt = rpc_new_client(args, xps, xprt, NULL);
488 if (IS_ERR(clnt))
489 return clnt;
490
491 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
492 int err = rpc_ping(clnt);
493 if (err != 0) {
494 rpc_shutdown_client(clnt);
495 return ERR_PTR(err);
496 }
497 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
498 int err = rpc_ping_noreply(clnt);
499 if (err != 0) {
500 rpc_shutdown_client(clnt);
501 return ERR_PTR(err);
502 }
503 }
504
505 clnt->cl_softrtry = 1;
506 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
507 clnt->cl_softrtry = 0;
508 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
509 clnt->cl_softerr = 1;
510 }
511
512 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
513 clnt->cl_autobind = 1;
514 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
515 clnt->cl_noretranstimeo = 1;
516 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
517 clnt->cl_discrtry = 1;
518 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
519 clnt->cl_chatty = 1;
520
521 return clnt;
522}
523
524/**
525 * rpc_create - create an RPC client and transport with one call
526 * @args: rpc_clnt create argument structure
527 *
528 * Creates and initializes an RPC transport and an RPC client.
529 *
530 * It can ping the server in order to determine if it is up, and to see if
531 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
532 * this behavior so asynchronous tasks can also use rpc_create.
533 */
534struct rpc_clnt *rpc_create(struct rpc_create_args *args)
535{
536 struct rpc_xprt *xprt;
537 struct xprt_create xprtargs = {
538 .net = args->net,
539 .ident = args->protocol,
540 .srcaddr = args->saddress,
541 .dstaddr = args->address,
542 .addrlen = args->addrsize,
543 .servername = args->servername,
544 .bc_xprt = args->bc_xprt,
545 .xprtsec = args->xprtsec,
546 .connect_timeout = args->connect_timeout,
547 .reconnect_timeout = args->reconnect_timeout,
548 };
549 char servername[48];
550 struct rpc_clnt *clnt;
551 int i;
552
553 if (args->bc_xprt) {
554 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
555 xprt = args->bc_xprt->xpt_bc_xprt;
556 if (xprt) {
557 xprt_get(xprt);
558 return rpc_create_xprt(args, xprt);
559 }
560 }
561
562 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
563 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
564 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
565 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
566 /*
567 * If the caller chooses not to specify a hostname, whip
568 * up a string representation of the passed-in address.
569 */
570 if (xprtargs.servername == NULL) {
571 struct sockaddr_un *sun =
572 (struct sockaddr_un *)args->address;
573 struct sockaddr_in *sin =
574 (struct sockaddr_in *)args->address;
575 struct sockaddr_in6 *sin6 =
576 (struct sockaddr_in6 *)args->address;
577
578 servername[0] = '\0';
579 switch (args->address->sa_family) {
580 case AF_LOCAL:
581 if (sun->sun_path[0])
582 snprintf(servername, sizeof(servername), "%s",
583 sun->sun_path);
584 else
585 snprintf(servername, sizeof(servername), "@%s",
586 sun->sun_path+1);
587 break;
588 case AF_INET:
589 snprintf(servername, sizeof(servername), "%pI4",
590 &sin->sin_addr.s_addr);
591 break;
592 case AF_INET6:
593 snprintf(servername, sizeof(servername), "%pI6",
594 &sin6->sin6_addr);
595 break;
596 default:
597 /* caller wants default server name, but
598 * address family isn't recognized. */
599 return ERR_PTR(-EINVAL);
600 }
601 xprtargs.servername = servername;
602 }
603
604 xprt = xprt_create_transport(&xprtargs);
605 if (IS_ERR(xprt))
606 return (struct rpc_clnt *)xprt;
607
608 /*
609 * By default, kernel RPC client connects from a reserved port.
610 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
611 * but it is always enabled for rpciod, which handles the connect
612 * operation.
613 */
614 xprt->resvport = 1;
615 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
616 xprt->resvport = 0;
617 xprt->reuseport = 0;
618 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
619 xprt->reuseport = 1;
620
621 clnt = rpc_create_xprt(args, xprt);
622 if (IS_ERR(clnt) || args->nconnect <= 1)
623 return clnt;
624
625 for (i = 0; i < args->nconnect - 1; i++) {
626 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
627 break;
628 }
629 return clnt;
630}
631EXPORT_SYMBOL_GPL(rpc_create);
632
633/*
634 * This function clones the RPC client structure. It allows us to share the
635 * same transport while varying parameters such as the authentication
636 * flavour.
637 */
638static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
639 struct rpc_clnt *clnt)
640{
641 struct rpc_xprt_switch *xps;
642 struct rpc_xprt *xprt;
643 struct rpc_clnt *new;
644 int err;
645
646 err = -ENOMEM;
647 rcu_read_lock();
648 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
649 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
650 rcu_read_unlock();
651 if (xprt == NULL || xps == NULL) {
652 xprt_put(xprt);
653 xprt_switch_put(xps);
654 goto out_err;
655 }
656 args->servername = xprt->servername;
657 args->nodename = clnt->cl_nodename;
658
659 new = rpc_new_client(args, xps, xprt, clnt);
660 if (IS_ERR(new))
661 return new;
662
663 /* Turn off autobind on clones */
664 new->cl_autobind = 0;
665 new->cl_softrtry = clnt->cl_softrtry;
666 new->cl_softerr = clnt->cl_softerr;
667 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
668 new->cl_discrtry = clnt->cl_discrtry;
669 new->cl_chatty = clnt->cl_chatty;
670 new->cl_principal = clnt->cl_principal;
671 new->cl_max_connect = clnt->cl_max_connect;
672 return new;
673
674out_err:
675 trace_rpc_clnt_clone_err(clnt, err);
676 return ERR_PTR(err);
677}
678
679/**
680 * rpc_clone_client - Clone an RPC client structure
681 *
682 * @clnt: RPC client whose parameters are copied
683 *
684 * Returns a fresh RPC client or an ERR_PTR.
685 */
686struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
687{
688 struct rpc_create_args args = {
689 .program = clnt->cl_program,
690 .prognumber = clnt->cl_prog,
691 .version = clnt->cl_vers,
692 .authflavor = clnt->cl_auth->au_flavor,
693 .cred = clnt->cl_cred,
694 };
695 return __rpc_clone_client(&args, clnt);
696}
697EXPORT_SYMBOL_GPL(rpc_clone_client);
698
699/**
700 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
701 *
702 * @clnt: RPC client whose parameters are copied
703 * @flavor: security flavor for new client
704 *
705 * Returns a fresh RPC client or an ERR_PTR.
706 */
707struct rpc_clnt *
708rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
709{
710 struct rpc_create_args args = {
711 .program = clnt->cl_program,
712 .prognumber = clnt->cl_prog,
713 .version = clnt->cl_vers,
714 .authflavor = flavor,
715 .cred = clnt->cl_cred,
716 };
717 return __rpc_clone_client(&args, clnt);
718}
719EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
720
721/**
722 * rpc_switch_client_transport: switch the RPC transport on the fly
723 * @clnt: pointer to a struct rpc_clnt
724 * @args: pointer to the new transport arguments
725 * @timeout: pointer to the new timeout parameters
726 *
727 * This function allows the caller to switch the RPC transport for the
728 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
729 * server, for instance. It assumes that the caller has ensured that
730 * there are no active RPC tasks by using some form of locking.
731 *
732 * Returns zero if "clnt" is now using the new xprt. Otherwise a
733 * negative errno is returned, and "clnt" continues to use the old
734 * xprt.
735 */
736int rpc_switch_client_transport(struct rpc_clnt *clnt,
737 struct xprt_create *args,
738 const struct rpc_timeout *timeout)
739{
740 const struct rpc_timeout *old_timeo;
741 rpc_authflavor_t pseudoflavor;
742 struct rpc_xprt_switch *xps, *oldxps;
743 struct rpc_xprt *xprt, *old;
744 struct rpc_clnt *parent;
745 int err;
746
747 args->xprtsec = clnt->cl_xprtsec;
748 xprt = xprt_create_transport(args);
749 if (IS_ERR(xprt))
750 return PTR_ERR(xprt);
751
752 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
753 if (xps == NULL) {
754 xprt_put(xprt);
755 return -ENOMEM;
756 }
757
758 pseudoflavor = clnt->cl_auth->au_flavor;
759
760 old_timeo = clnt->cl_timeout;
761 old = rpc_clnt_set_transport(clnt, xprt, timeout);
762 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
763
764 rpc_unregister_client(clnt);
765 __rpc_clnt_remove_pipedir(clnt);
766 rpc_sysfs_client_destroy(clnt);
767 rpc_clnt_debugfs_unregister(clnt);
768
769 /*
770 * A new transport was created. "clnt" therefore
771 * becomes the root of a new cl_parent tree. clnt's
772 * children, if it has any, still point to the old xprt.
773 */
774 parent = clnt->cl_parent;
775 clnt->cl_parent = clnt;
776
777 /*
778 * The old rpc_auth cache cannot be re-used. GSS
779 * contexts in particular are between a single
780 * client and server.
781 */
782 err = rpc_client_register(clnt, pseudoflavor, NULL);
783 if (err)
784 goto out_revert;
785
786 synchronize_rcu();
787 if (parent != clnt)
788 rpc_release_client(parent);
789 xprt_switch_put(oldxps);
790 xprt_put(old);
791 trace_rpc_clnt_replace_xprt(clnt);
792 return 0;
793
794out_revert:
795 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
796 rpc_clnt_set_transport(clnt, old, old_timeo);
797 clnt->cl_parent = parent;
798 rpc_client_register(clnt, pseudoflavor, NULL);
799 xprt_switch_put(xps);
800 xprt_put(xprt);
801 trace_rpc_clnt_replace_xprt_err(clnt);
802 return err;
803}
804EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
805
806static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt)
807{
808 struct rpc_xprt_switch *xps;
809
810 rcu_read_lock();
811 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
812 rcu_read_unlock();
813
814 return xps;
815}
816
817static
818int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
819 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
820{
821 struct rpc_xprt_switch *xps;
822
823 xps = rpc_clnt_xprt_switch_get(clnt);
824 if (xps == NULL)
825 return -EAGAIN;
826 func(xpi, xps);
827 xprt_switch_put(xps);
828 return 0;
829}
830
831static
832int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
833{
834 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
835}
836
837static
838int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
839 struct rpc_xprt_iter *xpi)
840{
841 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
842}
843
844/**
845 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
846 * @clnt: pointer to client
847 * @fn: function to apply
848 * @data: void pointer to function data
849 *
850 * Iterates through the list of RPC transports currently attached to the
851 * client and applies the function fn(clnt, xprt, data).
852 *
853 * On error, the iteration stops, and the function returns the error value.
854 */
855int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
856 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
857 void *data)
858{
859 struct rpc_xprt_iter xpi;
860 int ret;
861
862 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
863 if (ret)
864 return ret;
865 for (;;) {
866 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
867
868 if (!xprt)
869 break;
870 ret = fn(clnt, xprt, data);
871 xprt_put(xprt);
872 if (ret < 0)
873 break;
874 }
875 xprt_iter_destroy(&xpi);
876 return ret;
877}
878EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
879
880/*
881 * Kill all tasks for the given client.
882 * XXX: kill their descendants as well?
883 */
884void rpc_killall_tasks(struct rpc_clnt *clnt)
885{
886 struct rpc_task *rovr;
887
888
889 if (list_empty(&clnt->cl_tasks))
890 return;
891
892 /*
893 * Spin lock all_tasks to prevent changes...
894 */
895 trace_rpc_clnt_killall(clnt);
896 spin_lock(&clnt->cl_lock);
897 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
898 rpc_signal_task(rovr);
899 spin_unlock(&clnt->cl_lock);
900}
901EXPORT_SYMBOL_GPL(rpc_killall_tasks);
902
903/**
904 * rpc_cancel_tasks - try to cancel a set of RPC tasks
905 * @clnt: Pointer to RPC client
906 * @error: RPC task error value to set
907 * @fnmatch: Pointer to selector function
908 * @data: User data
909 *
910 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
911 * The argument @error must be a negative error value.
912 */
913unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
914 bool (*fnmatch)(const struct rpc_task *,
915 const void *),
916 const void *data)
917{
918 struct rpc_task *task;
919 unsigned long count = 0;
920
921 if (list_empty(&clnt->cl_tasks))
922 return 0;
923 /*
924 * Spin lock all_tasks to prevent changes...
925 */
926 spin_lock(&clnt->cl_lock);
927 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
928 if (!RPC_IS_ACTIVATED(task))
929 continue;
930 if (!fnmatch(task, data))
931 continue;
932 rpc_task_try_cancel(task, error);
933 count++;
934 }
935 spin_unlock(&clnt->cl_lock);
936 return count;
937}
938EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
939
940static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
941 struct rpc_xprt *xprt, void *dummy)
942{
943 if (xprt_connected(xprt))
944 xprt_force_disconnect(xprt);
945 return 0;
946}
947
948void rpc_clnt_disconnect(struct rpc_clnt *clnt)
949{
950 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
951}
952EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
953
954/*
955 * Properly shut down an RPC client, terminating all outstanding
956 * requests.
957 */
958void rpc_shutdown_client(struct rpc_clnt *clnt)
959{
960 might_sleep();
961
962 trace_rpc_clnt_shutdown(clnt);
963
964 while (!list_empty(&clnt->cl_tasks)) {
965 rpc_killall_tasks(clnt);
966 wait_event_timeout(destroy_wait,
967 list_empty(&clnt->cl_tasks), 1*HZ);
968 }
969
970 rpc_release_client(clnt);
971}
972EXPORT_SYMBOL_GPL(rpc_shutdown_client);
973
974/*
975 * Free an RPC client
976 */
977static void rpc_free_client_work(struct work_struct *work)
978{
979 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
980
981 trace_rpc_clnt_free(clnt);
982
983 /* These might block on processes that might allocate memory,
984 * so they cannot be called in rpciod, so they are handled separately
985 * here.
986 */
987 rpc_sysfs_client_destroy(clnt);
988 rpc_clnt_debugfs_unregister(clnt);
989 rpc_free_clid(clnt);
990 rpc_clnt_remove_pipedir(clnt);
991 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
992
993 kfree(clnt);
994 rpciod_down();
995}
996static struct rpc_clnt *
997rpc_free_client(struct rpc_clnt *clnt)
998{
999 struct rpc_clnt *parent = NULL;
1000
1001 trace_rpc_clnt_release(clnt);
1002 if (clnt->cl_parent != clnt)
1003 parent = clnt->cl_parent;
1004 rpc_unregister_client(clnt);
1005 rpc_free_iostats(clnt->cl_metrics);
1006 clnt->cl_metrics = NULL;
1007 xprt_iter_destroy(&clnt->cl_xpi);
1008 put_cred(clnt->cl_cred);
1009
1010 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
1011 schedule_work(&clnt->cl_work);
1012 return parent;
1013}
1014
1015/*
1016 * Free an RPC client
1017 */
1018static struct rpc_clnt *
1019rpc_free_auth(struct rpc_clnt *clnt)
1020{
1021 /*
1022 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
1023 * release remaining GSS contexts. This mechanism ensures
1024 * that it can do so safely.
1025 */
1026 if (clnt->cl_auth != NULL) {
1027 rpcauth_release(clnt->cl_auth);
1028 clnt->cl_auth = NULL;
1029 }
1030 if (refcount_dec_and_test(&clnt->cl_count))
1031 return rpc_free_client(clnt);
1032 return NULL;
1033}
1034
1035/*
1036 * Release reference to the RPC client
1037 */
1038void
1039rpc_release_client(struct rpc_clnt *clnt)
1040{
1041 do {
1042 if (list_empty(&clnt->cl_tasks))
1043 wake_up(&destroy_wait);
1044 if (refcount_dec_not_one(&clnt->cl_count))
1045 break;
1046 clnt = rpc_free_auth(clnt);
1047 } while (clnt != NULL);
1048}
1049EXPORT_SYMBOL_GPL(rpc_release_client);
1050
1051/**
1052 * rpc_bind_new_program - bind a new RPC program to an existing client
1053 * @old: old rpc_client
1054 * @program: rpc program to set
1055 * @vers: rpc program version
1056 *
1057 * Clones the rpc client and sets up a new RPC program. This is mainly
1058 * of use for enabling different RPC programs to share the same transport.
1059 * The Sun NFSv2/v3 ACL protocol can do this.
1060 */
1061struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1062 const struct rpc_program *program,
1063 u32 vers)
1064{
1065 struct rpc_create_args args = {
1066 .program = program,
1067 .prognumber = program->number,
1068 .version = vers,
1069 .authflavor = old->cl_auth->au_flavor,
1070 .cred = old->cl_cred,
1071 };
1072 struct rpc_clnt *clnt;
1073 int err;
1074
1075 clnt = __rpc_clone_client(&args, old);
1076 if (IS_ERR(clnt))
1077 goto out;
1078 err = rpc_ping(clnt);
1079 if (err != 0) {
1080 rpc_shutdown_client(clnt);
1081 clnt = ERR_PTR(err);
1082 }
1083out:
1084 return clnt;
1085}
1086EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1087
1088struct rpc_xprt *
1089rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1090{
1091 struct rpc_xprt_switch *xps;
1092
1093 if (!xprt)
1094 return NULL;
1095 rcu_read_lock();
1096 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1097 atomic_long_inc(&xps->xps_queuelen);
1098 rcu_read_unlock();
1099 atomic_long_inc(&xprt->queuelen);
1100
1101 return xprt;
1102}
1103
1104static void
1105rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1106{
1107 struct rpc_xprt_switch *xps;
1108
1109 atomic_long_dec(&xprt->queuelen);
1110 rcu_read_lock();
1111 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1112 atomic_long_dec(&xps->xps_queuelen);
1113 rcu_read_unlock();
1114
1115 xprt_put(xprt);
1116}
1117
1118void rpc_task_release_transport(struct rpc_task *task)
1119{
1120 struct rpc_xprt *xprt = task->tk_xprt;
1121
1122 if (xprt) {
1123 task->tk_xprt = NULL;
1124 if (task->tk_client)
1125 rpc_task_release_xprt(task->tk_client, xprt);
1126 else
1127 xprt_put(xprt);
1128 }
1129}
1130EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1131
1132void rpc_task_release_client(struct rpc_task *task)
1133{
1134 struct rpc_clnt *clnt = task->tk_client;
1135
1136 rpc_task_release_transport(task);
1137 if (clnt != NULL) {
1138 /* Remove from client task list */
1139 spin_lock(&clnt->cl_lock);
1140 list_del(&task->tk_task);
1141 spin_unlock(&clnt->cl_lock);
1142 task->tk_client = NULL;
1143
1144 rpc_release_client(clnt);
1145 }
1146}
1147
1148static struct rpc_xprt *
1149rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1150{
1151 struct rpc_xprt *xprt;
1152
1153 rcu_read_lock();
1154 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1155 rcu_read_unlock();
1156 return rpc_task_get_xprt(clnt, xprt);
1157}
1158
1159static struct rpc_xprt *
1160rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1161{
1162 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1163}
1164
1165static
1166void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1167{
1168 if (task->tk_xprt) {
1169 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1170 (task->tk_flags & RPC_TASK_MOVEABLE)))
1171 return;
1172 xprt_release(task);
1173 xprt_put(task->tk_xprt);
1174 }
1175 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1176 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1177 else
1178 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1179}
1180
1181static
1182void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1183{
1184 rpc_task_set_transport(task, clnt);
1185 task->tk_client = clnt;
1186 refcount_inc(&clnt->cl_count);
1187 if (clnt->cl_softrtry)
1188 task->tk_flags |= RPC_TASK_SOFT;
1189 if (clnt->cl_softerr)
1190 task->tk_flags |= RPC_TASK_TIMEOUT;
1191 if (clnt->cl_noretranstimeo)
1192 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1193 /* Add to the client's list of all tasks */
1194 spin_lock(&clnt->cl_lock);
1195 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1196 spin_unlock(&clnt->cl_lock);
1197}
1198
1199static void
1200rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1201{
1202 if (msg != NULL) {
1203 task->tk_msg.rpc_proc = msg->rpc_proc;
1204 task->tk_msg.rpc_argp = msg->rpc_argp;
1205 task->tk_msg.rpc_resp = msg->rpc_resp;
1206 task->tk_msg.rpc_cred = msg->rpc_cred;
1207 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1208 get_cred(task->tk_msg.rpc_cred);
1209 }
1210}
1211
1212/*
1213 * Default callback for async RPC calls
1214 */
1215static void
1216rpc_default_callback(struct rpc_task *task, void *data)
1217{
1218}
1219
1220static const struct rpc_call_ops rpc_default_ops = {
1221 .rpc_call_done = rpc_default_callback,
1222};
1223
1224/**
1225 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1226 * @task_setup_data: pointer to task initialisation data
1227 */
1228struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1229{
1230 struct rpc_task *task;
1231
1232 task = rpc_new_task(task_setup_data);
1233 if (IS_ERR(task))
1234 return task;
1235
1236 if (!RPC_IS_ASYNC(task))
1237 task->tk_flags |= RPC_TASK_CRED_NOREF;
1238
1239 rpc_task_set_client(task, task_setup_data->rpc_client);
1240 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1241
1242 if (task->tk_action == NULL)
1243 rpc_call_start(task);
1244
1245 atomic_inc(&task->tk_count);
1246 rpc_execute(task);
1247 return task;
1248}
1249EXPORT_SYMBOL_GPL(rpc_run_task);
1250
1251/**
1252 * rpc_call_sync - Perform a synchronous RPC call
1253 * @clnt: pointer to RPC client
1254 * @msg: RPC call parameters
1255 * @flags: RPC call flags
1256 */
1257int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1258{
1259 struct rpc_task *task;
1260 struct rpc_task_setup task_setup_data = {
1261 .rpc_client = clnt,
1262 .rpc_message = msg,
1263 .callback_ops = &rpc_default_ops,
1264 .flags = flags,
1265 };
1266 int status;
1267
1268 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1269 if (flags & RPC_TASK_ASYNC) {
1270 rpc_release_calldata(task_setup_data.callback_ops,
1271 task_setup_data.callback_data);
1272 return -EINVAL;
1273 }
1274
1275 task = rpc_run_task(&task_setup_data);
1276 if (IS_ERR(task))
1277 return PTR_ERR(task);
1278 status = task->tk_status;
1279 rpc_put_task(task);
1280 return status;
1281}
1282EXPORT_SYMBOL_GPL(rpc_call_sync);
1283
1284/**
1285 * rpc_call_async - Perform an asynchronous RPC call
1286 * @clnt: pointer to RPC client
1287 * @msg: RPC call parameters
1288 * @flags: RPC call flags
1289 * @tk_ops: RPC call ops
1290 * @data: user call data
1291 */
1292int
1293rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1294 const struct rpc_call_ops *tk_ops, void *data)
1295{
1296 struct rpc_task *task;
1297 struct rpc_task_setup task_setup_data = {
1298 .rpc_client = clnt,
1299 .rpc_message = msg,
1300 .callback_ops = tk_ops,
1301 .callback_data = data,
1302 .flags = flags|RPC_TASK_ASYNC,
1303 };
1304
1305 task = rpc_run_task(&task_setup_data);
1306 if (IS_ERR(task))
1307 return PTR_ERR(task);
1308 rpc_put_task(task);
1309 return 0;
1310}
1311EXPORT_SYMBOL_GPL(rpc_call_async);
1312
1313#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1314static void call_bc_encode(struct rpc_task *task);
1315
1316/**
1317 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1318 * rpc_execute against it
1319 * @req: RPC request
1320 * @timeout: timeout values to use for this task
1321 */
1322struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1323 struct rpc_timeout *timeout)
1324{
1325 struct rpc_task *task;
1326 struct rpc_task_setup task_setup_data = {
1327 .callback_ops = &rpc_default_ops,
1328 .flags = RPC_TASK_SOFTCONN |
1329 RPC_TASK_NO_RETRANS_TIMEOUT,
1330 };
1331
1332 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1333 /*
1334 * Create an rpc_task to send the data
1335 */
1336 task = rpc_new_task(&task_setup_data);
1337 if (IS_ERR(task)) {
1338 xprt_free_bc_request(req);
1339 return task;
1340 }
1341
1342 xprt_init_bc_request(req, task, timeout);
1343
1344 task->tk_action = call_bc_encode;
1345 atomic_inc(&task->tk_count);
1346 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1347 rpc_execute(task);
1348
1349 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1350 return task;
1351}
1352#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1353
1354/**
1355 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1356 * @req: RPC request to prepare
1357 * @pages: vector of struct page pointers
1358 * @base: offset in first page where receive should start, in bytes
1359 * @len: expected size of the upper layer data payload, in bytes
1360 * @hdrsize: expected size of upper layer reply header, in XDR words
1361 *
1362 */
1363void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1364 unsigned int base, unsigned int len,
1365 unsigned int hdrsize)
1366{
1367 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1368
1369 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1370 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1371}
1372EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1373
1374void
1375rpc_call_start(struct rpc_task *task)
1376{
1377 task->tk_action = call_start;
1378}
1379EXPORT_SYMBOL_GPL(rpc_call_start);
1380
1381/**
1382 * rpc_peeraddr - extract remote peer address from clnt's xprt
1383 * @clnt: RPC client structure
1384 * @buf: target buffer
1385 * @bufsize: length of target buffer
1386 *
1387 * Returns the number of bytes that are actually in the stored address.
1388 */
1389size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1390{
1391 size_t bytes;
1392 struct rpc_xprt *xprt;
1393
1394 rcu_read_lock();
1395 xprt = rcu_dereference(clnt->cl_xprt);
1396
1397 bytes = xprt->addrlen;
1398 if (bytes > bufsize)
1399 bytes = bufsize;
1400 memcpy(buf, &xprt->addr, bytes);
1401 rcu_read_unlock();
1402
1403 return bytes;
1404}
1405EXPORT_SYMBOL_GPL(rpc_peeraddr);
1406
1407/**
1408 * rpc_peeraddr2str - return remote peer address in printable format
1409 * @clnt: RPC client structure
1410 * @format: address format
1411 *
1412 * NB: the lifetime of the memory referenced by the returned pointer is
1413 * the same as the rpc_xprt itself. As long as the caller uses this
1414 * pointer, it must hold the RCU read lock.
1415 */
1416const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1417 enum rpc_display_format_t format)
1418{
1419 struct rpc_xprt *xprt;
1420
1421 xprt = rcu_dereference(clnt->cl_xprt);
1422
1423 if (xprt->address_strings[format] != NULL)
1424 return xprt->address_strings[format];
1425 else
1426 return "unprintable";
1427}
1428EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1429
1430static const struct sockaddr_in rpc_inaddr_loopback = {
1431 .sin_family = AF_INET,
1432 .sin_addr.s_addr = htonl(INADDR_ANY),
1433};
1434
1435static const struct sockaddr_in6 rpc_in6addr_loopback = {
1436 .sin6_family = AF_INET6,
1437 .sin6_addr = IN6ADDR_ANY_INIT,
1438};
1439
1440/*
1441 * Try a getsockname() on a connected datagram socket. Using a
1442 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1443 * This conserves the ephemeral port number space.
1444 *
1445 * Returns zero and fills in "buf" if successful; otherwise, a
1446 * negative errno is returned.
1447 */
1448static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1449 struct sockaddr *buf)
1450{
1451 struct socket *sock;
1452 int err;
1453
1454 err = __sock_create(net, sap->sa_family,
1455 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1456 if (err < 0) {
1457 dprintk("RPC: can't create UDP socket (%d)\n", err);
1458 goto out;
1459 }
1460
1461 switch (sap->sa_family) {
1462 case AF_INET:
1463 err = kernel_bind(sock,
1464 (struct sockaddr *)&rpc_inaddr_loopback,
1465 sizeof(rpc_inaddr_loopback));
1466 break;
1467 case AF_INET6:
1468 err = kernel_bind(sock,
1469 (struct sockaddr *)&rpc_in6addr_loopback,
1470 sizeof(rpc_in6addr_loopback));
1471 break;
1472 default:
1473 err = -EAFNOSUPPORT;
1474 goto out_release;
1475 }
1476 if (err < 0) {
1477 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1478 goto out_release;
1479 }
1480
1481 err = kernel_connect(sock, sap, salen, 0);
1482 if (err < 0) {
1483 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1484 goto out_release;
1485 }
1486
1487 err = kernel_getsockname(sock, buf);
1488 if (err < 0) {
1489 dprintk("RPC: getsockname failed (%d)\n", err);
1490 goto out_release;
1491 }
1492
1493 err = 0;
1494 if (buf->sa_family == AF_INET6) {
1495 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1496 sin6->sin6_scope_id = 0;
1497 }
1498 dprintk("RPC: %s succeeded\n", __func__);
1499
1500out_release:
1501 sock_release(sock);
1502out:
1503 return err;
1504}
1505
1506/*
1507 * Scraping a connected socket failed, so we don't have a useable
1508 * local address. Fallback: generate an address that will prevent
1509 * the server from calling us back.
1510 *
1511 * Returns zero and fills in "buf" if successful; otherwise, a
1512 * negative errno is returned.
1513 */
1514static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1515{
1516 switch (family) {
1517 case AF_INET:
1518 if (buflen < sizeof(rpc_inaddr_loopback))
1519 return -EINVAL;
1520 memcpy(buf, &rpc_inaddr_loopback,
1521 sizeof(rpc_inaddr_loopback));
1522 break;
1523 case AF_INET6:
1524 if (buflen < sizeof(rpc_in6addr_loopback))
1525 return -EINVAL;
1526 memcpy(buf, &rpc_in6addr_loopback,
1527 sizeof(rpc_in6addr_loopback));
1528 break;
1529 default:
1530 dprintk("RPC: %s: address family not supported\n",
1531 __func__);
1532 return -EAFNOSUPPORT;
1533 }
1534 dprintk("RPC: %s: succeeded\n", __func__);
1535 return 0;
1536}
1537
1538/**
1539 * rpc_localaddr - discover local endpoint address for an RPC client
1540 * @clnt: RPC client structure
1541 * @buf: target buffer
1542 * @buflen: size of target buffer, in bytes
1543 *
1544 * Returns zero and fills in "buf" and "buflen" if successful;
1545 * otherwise, a negative errno is returned.
1546 *
1547 * This works even if the underlying transport is not currently connected,
1548 * or if the upper layer never previously provided a source address.
1549 *
1550 * The result of this function call is transient: multiple calls in
1551 * succession may give different results, depending on how local
1552 * networking configuration changes over time.
1553 */
1554int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1555{
1556 struct sockaddr_storage address;
1557 struct sockaddr *sap = (struct sockaddr *)&address;
1558 struct rpc_xprt *xprt;
1559 struct net *net;
1560 size_t salen;
1561 int err;
1562
1563 rcu_read_lock();
1564 xprt = rcu_dereference(clnt->cl_xprt);
1565 salen = xprt->addrlen;
1566 memcpy(sap, &xprt->addr, salen);
1567 net = get_net(xprt->xprt_net);
1568 rcu_read_unlock();
1569
1570 rpc_set_port(sap, 0);
1571 err = rpc_sockname(net, sap, salen, buf);
1572 put_net(net);
1573 if (err != 0)
1574 /* Couldn't discover local address, return ANYADDR */
1575 return rpc_anyaddr(sap->sa_family, buf, buflen);
1576 return 0;
1577}
1578EXPORT_SYMBOL_GPL(rpc_localaddr);
1579
1580void
1581rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1582{
1583 struct rpc_xprt *xprt;
1584
1585 rcu_read_lock();
1586 xprt = rcu_dereference(clnt->cl_xprt);
1587 if (xprt->ops->set_buffer_size)
1588 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1589 rcu_read_unlock();
1590}
1591EXPORT_SYMBOL_GPL(rpc_setbufsize);
1592
1593/**
1594 * rpc_net_ns - Get the network namespace for this RPC client
1595 * @clnt: RPC client to query
1596 *
1597 */
1598struct net *rpc_net_ns(struct rpc_clnt *clnt)
1599{
1600 struct net *ret;
1601
1602 rcu_read_lock();
1603 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1604 rcu_read_unlock();
1605 return ret;
1606}
1607EXPORT_SYMBOL_GPL(rpc_net_ns);
1608
1609/**
1610 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1611 * @clnt: RPC client to query
1612 *
1613 * For stream transports, this is one RPC record fragment (see RFC
1614 * 1831), as we don't support multi-record requests yet. For datagram
1615 * transports, this is the size of an IP packet minus the IP, UDP, and
1616 * RPC header sizes.
1617 */
1618size_t rpc_max_payload(struct rpc_clnt *clnt)
1619{
1620 size_t ret;
1621
1622 rcu_read_lock();
1623 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1624 rcu_read_unlock();
1625 return ret;
1626}
1627EXPORT_SYMBOL_GPL(rpc_max_payload);
1628
1629/**
1630 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1631 * @clnt: RPC client to query
1632 */
1633size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1634{
1635 struct rpc_xprt *xprt;
1636 size_t ret;
1637
1638 rcu_read_lock();
1639 xprt = rcu_dereference(clnt->cl_xprt);
1640 ret = xprt->ops->bc_maxpayload(xprt);
1641 rcu_read_unlock();
1642 return ret;
1643}
1644EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1645
1646unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1647{
1648 struct rpc_xprt *xprt;
1649 unsigned int ret;
1650
1651 rcu_read_lock();
1652 xprt = rcu_dereference(clnt->cl_xprt);
1653 ret = xprt->ops->bc_num_slots(xprt);
1654 rcu_read_unlock();
1655 return ret;
1656}
1657EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1658
1659/**
1660 * rpc_force_rebind - force transport to check that remote port is unchanged
1661 * @clnt: client to rebind
1662 *
1663 */
1664void rpc_force_rebind(struct rpc_clnt *clnt)
1665{
1666 if (clnt->cl_autobind) {
1667 rcu_read_lock();
1668 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1669 rcu_read_unlock();
1670 }
1671}
1672EXPORT_SYMBOL_GPL(rpc_force_rebind);
1673
1674static int
1675__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1676{
1677 task->tk_status = 0;
1678 task->tk_rpc_status = 0;
1679 task->tk_action = action;
1680 return 1;
1681}
1682
1683/*
1684 * Restart an (async) RPC call. Usually called from within the
1685 * exit handler.
1686 */
1687int
1688rpc_restart_call(struct rpc_task *task)
1689{
1690 return __rpc_restart_call(task, call_start);
1691}
1692EXPORT_SYMBOL_GPL(rpc_restart_call);
1693
1694/*
1695 * Restart an (async) RPC call from the call_prepare state.
1696 * Usually called from within the exit handler.
1697 */
1698int
1699rpc_restart_call_prepare(struct rpc_task *task)
1700{
1701 if (task->tk_ops->rpc_call_prepare != NULL)
1702 return __rpc_restart_call(task, rpc_prepare_task);
1703 return rpc_restart_call(task);
1704}
1705EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1706
1707const char
1708*rpc_proc_name(const struct rpc_task *task)
1709{
1710 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1711
1712 if (proc) {
1713 if (proc->p_name)
1714 return proc->p_name;
1715 else
1716 return "NULL";
1717 } else
1718 return "no proc";
1719}
1720
1721static void
1722__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1723{
1724 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1725 rpc_task_set_rpc_status(task, rpc_status);
1726 rpc_exit(task, tk_status);
1727}
1728
1729static void
1730rpc_call_rpcerror(struct rpc_task *task, int status)
1731{
1732 __rpc_call_rpcerror(task, status, status);
1733}
1734
1735/*
1736 * 0. Initial state
1737 *
1738 * Other FSM states can be visited zero or more times, but
1739 * this state is visited exactly once for each RPC.
1740 */
1741static void
1742call_start(struct rpc_task *task)
1743{
1744 struct rpc_clnt *clnt = task->tk_client;
1745 int idx = task->tk_msg.rpc_proc->p_statidx;
1746
1747 trace_rpc_request(task);
1748
1749 if (task->tk_client->cl_shutdown) {
1750 rpc_call_rpcerror(task, -EIO);
1751 return;
1752 }
1753
1754 /* Increment call count (version might not be valid for ping) */
1755 if (clnt->cl_program->version[clnt->cl_vers])
1756 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1757 clnt->cl_stats->rpccnt++;
1758 task->tk_action = call_reserve;
1759 rpc_task_set_transport(task, clnt);
1760}
1761
1762/*
1763 * 1. Reserve an RPC call slot
1764 */
1765static void
1766call_reserve(struct rpc_task *task)
1767{
1768 task->tk_status = 0;
1769 task->tk_action = call_reserveresult;
1770 xprt_reserve(task);
1771}
1772
1773static void call_retry_reserve(struct rpc_task *task);
1774
1775/*
1776 * 1b. Grok the result of xprt_reserve()
1777 */
1778static void
1779call_reserveresult(struct rpc_task *task)
1780{
1781 int status = task->tk_status;
1782
1783 /*
1784 * After a call to xprt_reserve(), we must have either
1785 * a request slot or else an error status.
1786 */
1787 task->tk_status = 0;
1788 if (status >= 0) {
1789 if (task->tk_rqstp) {
1790 task->tk_action = call_refresh;
1791 return;
1792 }
1793
1794 rpc_call_rpcerror(task, -EIO);
1795 return;
1796 }
1797
1798 switch (status) {
1799 case -ENOMEM:
1800 rpc_delay(task, HZ >> 2);
1801 fallthrough;
1802 case -EAGAIN: /* woken up; retry */
1803 task->tk_action = call_retry_reserve;
1804 return;
1805 default:
1806 rpc_call_rpcerror(task, status);
1807 }
1808}
1809
1810/*
1811 * 1c. Retry reserving an RPC call slot
1812 */
1813static void
1814call_retry_reserve(struct rpc_task *task)
1815{
1816 task->tk_status = 0;
1817 task->tk_action = call_reserveresult;
1818 xprt_retry_reserve(task);
1819}
1820
1821/*
1822 * 2. Bind and/or refresh the credentials
1823 */
1824static void
1825call_refresh(struct rpc_task *task)
1826{
1827 task->tk_action = call_refreshresult;
1828 task->tk_status = 0;
1829 task->tk_client->cl_stats->rpcauthrefresh++;
1830 rpcauth_refreshcred(task);
1831}
1832
1833/*
1834 * 2a. Process the results of a credential refresh
1835 */
1836static void
1837call_refreshresult(struct rpc_task *task)
1838{
1839 int status = task->tk_status;
1840
1841 task->tk_status = 0;
1842 task->tk_action = call_refresh;
1843 switch (status) {
1844 case 0:
1845 if (rpcauth_uptodatecred(task)) {
1846 task->tk_action = call_allocate;
1847 return;
1848 }
1849 /* Use rate-limiting and a max number of retries if refresh
1850 * had status 0 but failed to update the cred.
1851 */
1852 fallthrough;
1853 case -ETIMEDOUT:
1854 rpc_delay(task, 3*HZ);
1855 fallthrough;
1856 case -EAGAIN:
1857 status = -EACCES;
1858 fallthrough;
1859 case -EKEYEXPIRED:
1860 if (!task->tk_cred_retry)
1861 break;
1862 task->tk_cred_retry--;
1863 trace_rpc_retry_refresh_status(task);
1864 return;
1865 case -ENOMEM:
1866 rpc_delay(task, HZ >> 4);
1867 return;
1868 }
1869 trace_rpc_refresh_status(task);
1870 rpc_call_rpcerror(task, status);
1871}
1872
1873/*
1874 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1875 * (Note: buffer memory is freed in xprt_release).
1876 */
1877static void
1878call_allocate(struct rpc_task *task)
1879{
1880 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1881 struct rpc_rqst *req = task->tk_rqstp;
1882 struct rpc_xprt *xprt = req->rq_xprt;
1883 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1884 int status;
1885
1886 task->tk_status = 0;
1887 task->tk_action = call_encode;
1888
1889 if (req->rq_buffer)
1890 return;
1891
1892 if (proc->p_proc != 0) {
1893 BUG_ON(proc->p_arglen == 0);
1894 if (proc->p_decode != NULL)
1895 BUG_ON(proc->p_replen == 0);
1896 }
1897
1898 /*
1899 * Calculate the size (in quads) of the RPC call
1900 * and reply headers, and convert both values
1901 * to byte sizes.
1902 */
1903 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1904 proc->p_arglen;
1905 req->rq_callsize <<= 2;
1906 /*
1907 * Note: the reply buffer must at minimum allocate enough space
1908 * for the 'struct accepted_reply' from RFC5531.
1909 */
1910 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1911 max_t(size_t, proc->p_replen, 2);
1912 req->rq_rcvsize <<= 2;
1913
1914 status = xprt->ops->buf_alloc(task);
1915 trace_rpc_buf_alloc(task, status);
1916 if (status == 0)
1917 return;
1918 if (status != -ENOMEM) {
1919 rpc_call_rpcerror(task, status);
1920 return;
1921 }
1922
1923 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1924 task->tk_action = call_allocate;
1925 rpc_delay(task, HZ>>4);
1926 return;
1927 }
1928
1929 rpc_call_rpcerror(task, -ERESTARTSYS);
1930}
1931
1932static int
1933rpc_task_need_encode(struct rpc_task *task)
1934{
1935 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1936 (!(task->tk_flags & RPC_TASK_SENT) ||
1937 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1938 xprt_request_need_retransmit(task));
1939}
1940
1941static void
1942rpc_xdr_encode(struct rpc_task *task)
1943{
1944 struct rpc_rqst *req = task->tk_rqstp;
1945 struct xdr_stream xdr;
1946
1947 xdr_buf_init(&req->rq_snd_buf,
1948 req->rq_buffer,
1949 req->rq_callsize);
1950 xdr_buf_init(&req->rq_rcv_buf,
1951 req->rq_rbuffer,
1952 req->rq_rcvsize);
1953
1954 req->rq_reply_bytes_recvd = 0;
1955 req->rq_snd_buf.head[0].iov_len = 0;
1956 xdr_init_encode(&xdr, &req->rq_snd_buf,
1957 req->rq_snd_buf.head[0].iov_base, req);
1958 if (rpc_encode_header(task, &xdr))
1959 return;
1960
1961 task->tk_status = rpcauth_wrap_req(task, &xdr);
1962}
1963
1964/*
1965 * 3. Encode arguments of an RPC call
1966 */
1967static void
1968call_encode(struct rpc_task *task)
1969{
1970 if (!rpc_task_need_encode(task))
1971 goto out;
1972
1973 /* Dequeue task from the receive queue while we're encoding */
1974 xprt_request_dequeue_xprt(task);
1975 /* Encode here so that rpcsec_gss can use correct sequence number. */
1976 rpc_xdr_encode(task);
1977 /* Add task to reply queue before transmission to avoid races */
1978 if (task->tk_status == 0 && rpc_reply_expected(task))
1979 task->tk_status = xprt_request_enqueue_receive(task);
1980 /* Did the encode result in an error condition? */
1981 if (task->tk_status != 0) {
1982 /* Was the error nonfatal? */
1983 switch (task->tk_status) {
1984 case -EAGAIN:
1985 case -ENOMEM:
1986 rpc_delay(task, HZ >> 4);
1987 break;
1988 case -EKEYEXPIRED:
1989 if (!task->tk_cred_retry) {
1990 rpc_call_rpcerror(task, task->tk_status);
1991 } else {
1992 task->tk_action = call_refresh;
1993 task->tk_cred_retry--;
1994 trace_rpc_retry_refresh_status(task);
1995 }
1996 break;
1997 default:
1998 rpc_call_rpcerror(task, task->tk_status);
1999 }
2000 return;
2001 }
2002
2003 xprt_request_enqueue_transmit(task);
2004out:
2005 task->tk_action = call_transmit;
2006 /* Check that the connection is OK */
2007 if (!xprt_bound(task->tk_xprt))
2008 task->tk_action = call_bind;
2009 else if (!xprt_connected(task->tk_xprt))
2010 task->tk_action = call_connect;
2011}
2012
2013/*
2014 * Helpers to check if the task was already transmitted, and
2015 * to take action when that is the case.
2016 */
2017static bool
2018rpc_task_transmitted(struct rpc_task *task)
2019{
2020 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
2021}
2022
2023static void
2024rpc_task_handle_transmitted(struct rpc_task *task)
2025{
2026 xprt_end_transmit(task);
2027 task->tk_action = call_transmit_status;
2028}
2029
2030/*
2031 * 4. Get the server port number if not yet set
2032 */
2033static void
2034call_bind(struct rpc_task *task)
2035{
2036 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2037
2038 if (rpc_task_transmitted(task)) {
2039 rpc_task_handle_transmitted(task);
2040 return;
2041 }
2042
2043 if (xprt_bound(xprt)) {
2044 task->tk_action = call_connect;
2045 return;
2046 }
2047
2048 task->tk_action = call_bind_status;
2049 if (!xprt_prepare_transmit(task))
2050 return;
2051
2052 xprt->ops->rpcbind(task);
2053}
2054
2055/*
2056 * 4a. Sort out bind result
2057 */
2058static void
2059call_bind_status(struct rpc_task *task)
2060{
2061 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2062 int status = -EIO;
2063
2064 if (rpc_task_transmitted(task)) {
2065 rpc_task_handle_transmitted(task);
2066 return;
2067 }
2068
2069 if (task->tk_status >= 0)
2070 goto out_next;
2071 if (xprt_bound(xprt)) {
2072 task->tk_status = 0;
2073 goto out_next;
2074 }
2075
2076 switch (task->tk_status) {
2077 case -ENOMEM:
2078 rpc_delay(task, HZ >> 2);
2079 goto retry_timeout;
2080 case -EACCES:
2081 trace_rpcb_prog_unavail_err(task);
2082 /* fail immediately if this is an RPC ping */
2083 if (task->tk_msg.rpc_proc->p_proc == 0) {
2084 status = -EOPNOTSUPP;
2085 break;
2086 }
2087 rpc_delay(task, 3*HZ);
2088 goto retry_timeout;
2089 case -ENOBUFS:
2090 rpc_delay(task, HZ >> 2);
2091 goto retry_timeout;
2092 case -EAGAIN:
2093 goto retry_timeout;
2094 case -ETIMEDOUT:
2095 trace_rpcb_timeout_err(task);
2096 goto retry_timeout;
2097 case -EPFNOSUPPORT:
2098 /* server doesn't support any rpcbind version we know of */
2099 trace_rpcb_bind_version_err(task);
2100 break;
2101 case -EPROTONOSUPPORT:
2102 trace_rpcb_bind_version_err(task);
2103 goto retry_timeout;
2104 case -ECONNREFUSED: /* connection problems */
2105 case -ECONNRESET:
2106 case -ECONNABORTED:
2107 case -ENOTCONN:
2108 case -EHOSTDOWN:
2109 case -ENETDOWN:
2110 case -EHOSTUNREACH:
2111 case -ENETUNREACH:
2112 case -EPIPE:
2113 trace_rpcb_unreachable_err(task);
2114 if (!RPC_IS_SOFTCONN(task)) {
2115 rpc_delay(task, 5*HZ);
2116 goto retry_timeout;
2117 }
2118 status = task->tk_status;
2119 break;
2120 default:
2121 trace_rpcb_unrecognized_err(task);
2122 }
2123
2124 rpc_call_rpcerror(task, status);
2125 return;
2126out_next:
2127 task->tk_action = call_connect;
2128 return;
2129retry_timeout:
2130 task->tk_status = 0;
2131 task->tk_action = call_bind;
2132 rpc_check_timeout(task);
2133}
2134
2135/*
2136 * 4b. Connect to the RPC server
2137 */
2138static void
2139call_connect(struct rpc_task *task)
2140{
2141 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2142
2143 if (rpc_task_transmitted(task)) {
2144 rpc_task_handle_transmitted(task);
2145 return;
2146 }
2147
2148 if (xprt_connected(xprt)) {
2149 task->tk_action = call_transmit;
2150 return;
2151 }
2152
2153 task->tk_action = call_connect_status;
2154 if (task->tk_status < 0)
2155 return;
2156 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2157 rpc_call_rpcerror(task, -ENOTCONN);
2158 return;
2159 }
2160 if (!xprt_prepare_transmit(task))
2161 return;
2162 xprt_connect(task);
2163}
2164
2165/*
2166 * 4c. Sort out connect result
2167 */
2168static void
2169call_connect_status(struct rpc_task *task)
2170{
2171 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2172 struct rpc_clnt *clnt = task->tk_client;
2173 int status = task->tk_status;
2174
2175 if (rpc_task_transmitted(task)) {
2176 rpc_task_handle_transmitted(task);
2177 return;
2178 }
2179
2180 trace_rpc_connect_status(task);
2181
2182 if (task->tk_status == 0) {
2183 clnt->cl_stats->netreconn++;
2184 goto out_next;
2185 }
2186 if (xprt_connected(xprt)) {
2187 task->tk_status = 0;
2188 goto out_next;
2189 }
2190
2191 task->tk_status = 0;
2192 switch (status) {
2193 case -ECONNREFUSED:
2194 case -ECONNRESET:
2195 /* A positive refusal suggests a rebind is needed. */
2196 if (RPC_IS_SOFTCONN(task))
2197 break;
2198 if (clnt->cl_autobind) {
2199 rpc_force_rebind(clnt);
2200 goto out_retry;
2201 }
2202 fallthrough;
2203 case -ECONNABORTED:
2204 case -ENETDOWN:
2205 case -ENETUNREACH:
2206 case -EHOSTUNREACH:
2207 case -EPIPE:
2208 case -EPROTO:
2209 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2210 task->tk_rqstp->rq_connect_cookie);
2211 if (RPC_IS_SOFTCONN(task))
2212 break;
2213 /* retry with existing socket, after a delay */
2214 rpc_delay(task, 3*HZ);
2215 fallthrough;
2216 case -EADDRINUSE:
2217 case -ENOTCONN:
2218 case -EAGAIN:
2219 case -ETIMEDOUT:
2220 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2221 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2222 test_bit(XPRT_REMOVE, &xprt->state)) {
2223 struct rpc_xprt *saved = task->tk_xprt;
2224 struct rpc_xprt_switch *xps;
2225
2226 xps = rpc_clnt_xprt_switch_get(clnt);
2227 if (xps->xps_nxprts > 1) {
2228 long value;
2229
2230 xprt_release(task);
2231 value = atomic_long_dec_return(&xprt->queuelen);
2232 if (value == 0)
2233 rpc_xprt_switch_remove_xprt(xps, saved,
2234 true);
2235 xprt_put(saved);
2236 task->tk_xprt = NULL;
2237 task->tk_action = call_start;
2238 }
2239 xprt_switch_put(xps);
2240 if (!task->tk_xprt)
2241 goto out;
2242 }
2243 goto out_retry;
2244 case -ENOBUFS:
2245 rpc_delay(task, HZ >> 2);
2246 goto out_retry;
2247 }
2248 rpc_call_rpcerror(task, status);
2249 return;
2250out_next:
2251 task->tk_action = call_transmit;
2252 return;
2253out_retry:
2254 /* Check for timeouts before looping back to call_bind */
2255 task->tk_action = call_bind;
2256out:
2257 rpc_check_timeout(task);
2258}
2259
2260/*
2261 * 5. Transmit the RPC request, and wait for reply
2262 */
2263static void
2264call_transmit(struct rpc_task *task)
2265{
2266 if (rpc_task_transmitted(task)) {
2267 rpc_task_handle_transmitted(task);
2268 return;
2269 }
2270
2271 task->tk_action = call_transmit_status;
2272 if (!xprt_prepare_transmit(task))
2273 return;
2274 task->tk_status = 0;
2275 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2276 if (!xprt_connected(task->tk_xprt)) {
2277 task->tk_status = -ENOTCONN;
2278 return;
2279 }
2280 xprt_transmit(task);
2281 }
2282 xprt_end_transmit(task);
2283}
2284
2285/*
2286 * 5a. Handle cleanup after a transmission
2287 */
2288static void
2289call_transmit_status(struct rpc_task *task)
2290{
2291 task->tk_action = call_status;
2292
2293 /*
2294 * Common case: success. Force the compiler to put this
2295 * test first.
2296 */
2297 if (rpc_task_transmitted(task)) {
2298 task->tk_status = 0;
2299 xprt_request_wait_receive(task);
2300 return;
2301 }
2302
2303 switch (task->tk_status) {
2304 default:
2305 break;
2306 case -EBADMSG:
2307 task->tk_status = 0;
2308 task->tk_action = call_encode;
2309 break;
2310 /*
2311 * Special cases: if we've been waiting on the
2312 * socket's write_space() callback, or if the
2313 * socket just returned a connection error,
2314 * then hold onto the transport lock.
2315 */
2316 case -ENOMEM:
2317 case -ENOBUFS:
2318 rpc_delay(task, HZ>>2);
2319 fallthrough;
2320 case -EBADSLT:
2321 case -EAGAIN:
2322 task->tk_action = call_transmit;
2323 task->tk_status = 0;
2324 break;
2325 case -ECONNREFUSED:
2326 case -EHOSTDOWN:
2327 case -ENETDOWN:
2328 case -EHOSTUNREACH:
2329 case -ENETUNREACH:
2330 case -EPERM:
2331 if (RPC_IS_SOFTCONN(task)) {
2332 if (!task->tk_msg.rpc_proc->p_proc)
2333 trace_xprt_ping(task->tk_xprt,
2334 task->tk_status);
2335 rpc_call_rpcerror(task, task->tk_status);
2336 return;
2337 }
2338 fallthrough;
2339 case -ECONNRESET:
2340 case -ECONNABORTED:
2341 case -EADDRINUSE:
2342 case -ENOTCONN:
2343 case -EPIPE:
2344 task->tk_action = call_bind;
2345 task->tk_status = 0;
2346 break;
2347 }
2348 rpc_check_timeout(task);
2349}
2350
2351#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2352static void call_bc_transmit(struct rpc_task *task);
2353static void call_bc_transmit_status(struct rpc_task *task);
2354
2355static void
2356call_bc_encode(struct rpc_task *task)
2357{
2358 xprt_request_enqueue_transmit(task);
2359 task->tk_action = call_bc_transmit;
2360}
2361
2362/*
2363 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2364 * addition, disconnect on connectivity errors.
2365 */
2366static void
2367call_bc_transmit(struct rpc_task *task)
2368{
2369 task->tk_action = call_bc_transmit_status;
2370 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2371 if (!xprt_prepare_transmit(task))
2372 return;
2373 task->tk_status = 0;
2374 xprt_transmit(task);
2375 }
2376 xprt_end_transmit(task);
2377}
2378
2379static void
2380call_bc_transmit_status(struct rpc_task *task)
2381{
2382 struct rpc_rqst *req = task->tk_rqstp;
2383
2384 if (rpc_task_transmitted(task))
2385 task->tk_status = 0;
2386
2387 switch (task->tk_status) {
2388 case 0:
2389 /* Success */
2390 case -ENETDOWN:
2391 case -EHOSTDOWN:
2392 case -EHOSTUNREACH:
2393 case -ENETUNREACH:
2394 case -ECONNRESET:
2395 case -ECONNREFUSED:
2396 case -EADDRINUSE:
2397 case -ENOTCONN:
2398 case -EPIPE:
2399 break;
2400 case -ENOMEM:
2401 case -ENOBUFS:
2402 rpc_delay(task, HZ>>2);
2403 fallthrough;
2404 case -EBADSLT:
2405 case -EAGAIN:
2406 task->tk_status = 0;
2407 task->tk_action = call_bc_transmit;
2408 return;
2409 case -ETIMEDOUT:
2410 /*
2411 * Problem reaching the server. Disconnect and let the
2412 * forechannel reestablish the connection. The server will
2413 * have to retransmit the backchannel request and we'll
2414 * reprocess it. Since these ops are idempotent, there's no
2415 * need to cache our reply at this time.
2416 */
2417 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2418 "error: %d\n", task->tk_status);
2419 xprt_conditional_disconnect(req->rq_xprt,
2420 req->rq_connect_cookie);
2421 break;
2422 default:
2423 /*
2424 * We were unable to reply and will have to drop the
2425 * request. The server should reconnect and retransmit.
2426 */
2427 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2428 "error: %d\n", task->tk_status);
2429 break;
2430 }
2431 task->tk_action = rpc_exit_task;
2432}
2433#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2434
2435/*
2436 * 6. Sort out the RPC call status
2437 */
2438static void
2439call_status(struct rpc_task *task)
2440{
2441 struct rpc_clnt *clnt = task->tk_client;
2442 int status;
2443
2444 if (!task->tk_msg.rpc_proc->p_proc)
2445 trace_xprt_ping(task->tk_xprt, task->tk_status);
2446
2447 status = task->tk_status;
2448 if (status >= 0) {
2449 task->tk_action = call_decode;
2450 return;
2451 }
2452
2453 trace_rpc_call_status(task);
2454 task->tk_status = 0;
2455 switch(status) {
2456 case -EHOSTDOWN:
2457 case -ENETDOWN:
2458 case -EHOSTUNREACH:
2459 case -ENETUNREACH:
2460 case -EPERM:
2461 if (RPC_IS_SOFTCONN(task))
2462 goto out_exit;
2463 /*
2464 * Delay any retries for 3 seconds, then handle as if it
2465 * were a timeout.
2466 */
2467 rpc_delay(task, 3*HZ);
2468 fallthrough;
2469 case -ETIMEDOUT:
2470 break;
2471 case -ECONNREFUSED:
2472 case -ECONNRESET:
2473 case -ECONNABORTED:
2474 case -ENOTCONN:
2475 rpc_force_rebind(clnt);
2476 break;
2477 case -EADDRINUSE:
2478 rpc_delay(task, 3*HZ);
2479 fallthrough;
2480 case -EPIPE:
2481 case -EAGAIN:
2482 break;
2483 case -ENFILE:
2484 case -ENOBUFS:
2485 case -ENOMEM:
2486 rpc_delay(task, HZ>>2);
2487 break;
2488 case -EIO:
2489 /* shutdown or soft timeout */
2490 goto out_exit;
2491 default:
2492 if (clnt->cl_chatty)
2493 printk("%s: RPC call returned error %d\n",
2494 clnt->cl_program->name, -status);
2495 goto out_exit;
2496 }
2497 task->tk_action = call_encode;
2498 rpc_check_timeout(task);
2499 return;
2500out_exit:
2501 rpc_call_rpcerror(task, status);
2502}
2503
2504static bool
2505rpc_check_connected(const struct rpc_rqst *req)
2506{
2507 /* No allocated request or transport? return true */
2508 if (!req || !req->rq_xprt)
2509 return true;
2510 return xprt_connected(req->rq_xprt);
2511}
2512
2513static void
2514rpc_check_timeout(struct rpc_task *task)
2515{
2516 struct rpc_clnt *clnt = task->tk_client;
2517
2518 if (RPC_SIGNALLED(task))
2519 return;
2520
2521 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2522 return;
2523
2524 trace_rpc_timeout_status(task);
2525 task->tk_timeouts++;
2526
2527 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2528 rpc_call_rpcerror(task, -ETIMEDOUT);
2529 return;
2530 }
2531
2532 if (RPC_IS_SOFT(task)) {
2533 /*
2534 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2535 * been sent, it should time out only if the transport
2536 * connection gets terminally broken.
2537 */
2538 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2539 rpc_check_connected(task->tk_rqstp))
2540 return;
2541
2542 if (clnt->cl_chatty) {
2543 pr_notice_ratelimited(
2544 "%s: server %s not responding, timed out\n",
2545 clnt->cl_program->name,
2546 task->tk_xprt->servername);
2547 }
2548 if (task->tk_flags & RPC_TASK_TIMEOUT)
2549 rpc_call_rpcerror(task, -ETIMEDOUT);
2550 else
2551 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2552 return;
2553 }
2554
2555 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2556 task->tk_flags |= RPC_CALL_MAJORSEEN;
2557 if (clnt->cl_chatty) {
2558 pr_notice_ratelimited(
2559 "%s: server %s not responding, still trying\n",
2560 clnt->cl_program->name,
2561 task->tk_xprt->servername);
2562 }
2563 }
2564 rpc_force_rebind(clnt);
2565 /*
2566 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2567 * event? RFC2203 requires the server to drop all such requests.
2568 */
2569 rpcauth_invalcred(task);
2570}
2571
2572/*
2573 * 7. Decode the RPC reply
2574 */
2575static void
2576call_decode(struct rpc_task *task)
2577{
2578 struct rpc_clnt *clnt = task->tk_client;
2579 struct rpc_rqst *req = task->tk_rqstp;
2580 struct xdr_stream xdr;
2581 int err;
2582
2583 if (!task->tk_msg.rpc_proc->p_decode) {
2584 task->tk_action = rpc_exit_task;
2585 return;
2586 }
2587
2588 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2589 if (clnt->cl_chatty) {
2590 pr_notice_ratelimited("%s: server %s OK\n",
2591 clnt->cl_program->name,
2592 task->tk_xprt->servername);
2593 }
2594 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2595 }
2596
2597 /*
2598 * Did we ever call xprt_complete_rqst()? If not, we should assume
2599 * the message is incomplete.
2600 */
2601 err = -EAGAIN;
2602 if (!req->rq_reply_bytes_recvd)
2603 goto out;
2604
2605 /* Ensure that we see all writes made by xprt_complete_rqst()
2606 * before it changed req->rq_reply_bytes_recvd.
2607 */
2608 smp_rmb();
2609
2610 req->rq_rcv_buf.len = req->rq_private_buf.len;
2611 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2612
2613 /* Check that the softirq receive buffer is valid */
2614 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2615 sizeof(req->rq_rcv_buf)) != 0);
2616
2617 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2618 req->rq_rcv_buf.head[0].iov_base, req);
2619 err = rpc_decode_header(task, &xdr);
2620out:
2621 switch (err) {
2622 case 0:
2623 task->tk_action = rpc_exit_task;
2624 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2625 xdr_finish_decode(&xdr);
2626 return;
2627 case -EAGAIN:
2628 task->tk_status = 0;
2629 if (task->tk_client->cl_discrtry)
2630 xprt_conditional_disconnect(req->rq_xprt,
2631 req->rq_connect_cookie);
2632 task->tk_action = call_encode;
2633 rpc_check_timeout(task);
2634 break;
2635 case -EKEYREJECTED:
2636 task->tk_action = call_reserve;
2637 rpc_check_timeout(task);
2638 rpcauth_invalcred(task);
2639 /* Ensure we obtain a new XID if we retry! */
2640 xprt_release(task);
2641 }
2642}
2643
2644static int
2645rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2646{
2647 struct rpc_clnt *clnt = task->tk_client;
2648 struct rpc_rqst *req = task->tk_rqstp;
2649 __be32 *p;
2650 int error;
2651
2652 error = -EMSGSIZE;
2653 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2654 if (!p)
2655 goto out_fail;
2656 *p++ = req->rq_xid;
2657 *p++ = rpc_call;
2658 *p++ = cpu_to_be32(RPC_VERSION);
2659 *p++ = cpu_to_be32(clnt->cl_prog);
2660 *p++ = cpu_to_be32(clnt->cl_vers);
2661 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2662
2663 error = rpcauth_marshcred(task, xdr);
2664 if (error < 0)
2665 goto out_fail;
2666 return 0;
2667out_fail:
2668 trace_rpc_bad_callhdr(task);
2669 rpc_call_rpcerror(task, error);
2670 return error;
2671}
2672
2673static noinline int
2674rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2675{
2676 struct rpc_clnt *clnt = task->tk_client;
2677 int error;
2678 __be32 *p;
2679
2680 /* RFC-1014 says that the representation of XDR data must be a
2681 * multiple of four bytes
2682 * - if it isn't pointer subtraction in the NFS client may give
2683 * undefined results
2684 */
2685 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2686 goto out_unparsable;
2687
2688 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2689 if (!p)
2690 goto out_unparsable;
2691 p++; /* skip XID */
2692 if (*p++ != rpc_reply)
2693 goto out_unparsable;
2694 if (*p++ != rpc_msg_accepted)
2695 goto out_msg_denied;
2696
2697 error = rpcauth_checkverf(task, xdr);
2698 if (error)
2699 goto out_verifier;
2700
2701 p = xdr_inline_decode(xdr, sizeof(*p));
2702 if (!p)
2703 goto out_unparsable;
2704 switch (*p) {
2705 case rpc_success:
2706 return 0;
2707 case rpc_prog_unavail:
2708 trace_rpc__prog_unavail(task);
2709 error = -EPFNOSUPPORT;
2710 goto out_err;
2711 case rpc_prog_mismatch:
2712 trace_rpc__prog_mismatch(task);
2713 error = -EPROTONOSUPPORT;
2714 goto out_err;
2715 case rpc_proc_unavail:
2716 trace_rpc__proc_unavail(task);
2717 error = -EOPNOTSUPP;
2718 goto out_err;
2719 case rpc_garbage_args:
2720 case rpc_system_err:
2721 trace_rpc__garbage_args(task);
2722 error = -EIO;
2723 break;
2724 default:
2725 goto out_unparsable;
2726 }
2727
2728out_garbage:
2729 clnt->cl_stats->rpcgarbage++;
2730 if (task->tk_garb_retry) {
2731 task->tk_garb_retry--;
2732 task->tk_action = call_encode;
2733 return -EAGAIN;
2734 }
2735out_err:
2736 rpc_call_rpcerror(task, error);
2737 return error;
2738
2739out_unparsable:
2740 trace_rpc__unparsable(task);
2741 error = -EIO;
2742 goto out_garbage;
2743
2744out_verifier:
2745 trace_rpc_bad_verifier(task);
2746 switch (error) {
2747 case -EPROTONOSUPPORT:
2748 goto out_err;
2749 case -EACCES:
2750 /* Re-encode with a fresh cred */
2751 fallthrough;
2752 default:
2753 goto out_garbage;
2754 }
2755
2756out_msg_denied:
2757 error = -EACCES;
2758 p = xdr_inline_decode(xdr, sizeof(*p));
2759 if (!p)
2760 goto out_unparsable;
2761 switch (*p++) {
2762 case rpc_auth_error:
2763 break;
2764 case rpc_mismatch:
2765 trace_rpc__mismatch(task);
2766 error = -EPROTONOSUPPORT;
2767 goto out_err;
2768 default:
2769 goto out_unparsable;
2770 }
2771
2772 p = xdr_inline_decode(xdr, sizeof(*p));
2773 if (!p)
2774 goto out_unparsable;
2775 switch (*p++) {
2776 case rpc_autherr_rejectedcred:
2777 case rpc_autherr_rejectedverf:
2778 case rpcsec_gsserr_credproblem:
2779 case rpcsec_gsserr_ctxproblem:
2780 rpcauth_invalcred(task);
2781 if (!task->tk_cred_retry)
2782 break;
2783 task->tk_cred_retry--;
2784 trace_rpc__stale_creds(task);
2785 return -EKEYREJECTED;
2786 case rpc_autherr_badcred:
2787 case rpc_autherr_badverf:
2788 /* possibly garbled cred/verf? */
2789 if (!task->tk_garb_retry)
2790 break;
2791 task->tk_garb_retry--;
2792 trace_rpc__bad_creds(task);
2793 task->tk_action = call_encode;
2794 return -EAGAIN;
2795 case rpc_autherr_tooweak:
2796 trace_rpc__auth_tooweak(task);
2797 pr_warn("RPC: server %s requires stronger authentication.\n",
2798 task->tk_xprt->servername);
2799 break;
2800 default:
2801 goto out_unparsable;
2802 }
2803 goto out_err;
2804}
2805
2806static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2807 const void *obj)
2808{
2809}
2810
2811static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2812 void *obj)
2813{
2814 return 0;
2815}
2816
2817static const struct rpc_procinfo rpcproc_null = {
2818 .p_encode = rpcproc_encode_null,
2819 .p_decode = rpcproc_decode_null,
2820};
2821
2822static const struct rpc_procinfo rpcproc_null_noreply = {
2823 .p_encode = rpcproc_encode_null,
2824};
2825
2826static void
2827rpc_null_call_prepare(struct rpc_task *task, void *data)
2828{
2829 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2830 rpc_call_start(task);
2831}
2832
2833static const struct rpc_call_ops rpc_null_ops = {
2834 .rpc_call_prepare = rpc_null_call_prepare,
2835 .rpc_call_done = rpc_default_callback,
2836};
2837
2838static
2839struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2840 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2841 const struct rpc_call_ops *ops, void *data)
2842{
2843 struct rpc_message msg = {
2844 .rpc_proc = &rpcproc_null,
2845 };
2846 struct rpc_task_setup task_setup_data = {
2847 .rpc_client = clnt,
2848 .rpc_xprt = xprt,
2849 .rpc_message = &msg,
2850 .rpc_op_cred = cred,
2851 .callback_ops = ops ?: &rpc_null_ops,
2852 .callback_data = data,
2853 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2854 RPC_TASK_NULLCREDS,
2855 };
2856
2857 return rpc_run_task(&task_setup_data);
2858}
2859
2860struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2861{
2862 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2863}
2864EXPORT_SYMBOL_GPL(rpc_call_null);
2865
2866static int rpc_ping(struct rpc_clnt *clnt)
2867{
2868 struct rpc_task *task;
2869 int status;
2870
2871 if (clnt->cl_auth->au_ops->ping)
2872 return clnt->cl_auth->au_ops->ping(clnt);
2873
2874 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2875 if (IS_ERR(task))
2876 return PTR_ERR(task);
2877 status = task->tk_status;
2878 rpc_put_task(task);
2879 return status;
2880}
2881
2882static int rpc_ping_noreply(struct rpc_clnt *clnt)
2883{
2884 struct rpc_message msg = {
2885 .rpc_proc = &rpcproc_null_noreply,
2886 };
2887 struct rpc_task_setup task_setup_data = {
2888 .rpc_client = clnt,
2889 .rpc_message = &msg,
2890 .callback_ops = &rpc_null_ops,
2891 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2892 };
2893 struct rpc_task *task;
2894 int status;
2895
2896 task = rpc_run_task(&task_setup_data);
2897 if (IS_ERR(task))
2898 return PTR_ERR(task);
2899 status = task->tk_status;
2900 rpc_put_task(task);
2901 return status;
2902}
2903
2904struct rpc_cb_add_xprt_calldata {
2905 struct rpc_xprt_switch *xps;
2906 struct rpc_xprt *xprt;
2907};
2908
2909static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2910{
2911 struct rpc_cb_add_xprt_calldata *data = calldata;
2912
2913 if (task->tk_status == 0)
2914 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2915}
2916
2917static void rpc_cb_add_xprt_release(void *calldata)
2918{
2919 struct rpc_cb_add_xprt_calldata *data = calldata;
2920
2921 xprt_put(data->xprt);
2922 xprt_switch_put(data->xps);
2923 kfree(data);
2924}
2925
2926static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2927 .rpc_call_prepare = rpc_null_call_prepare,
2928 .rpc_call_done = rpc_cb_add_xprt_done,
2929 .rpc_release = rpc_cb_add_xprt_release,
2930};
2931
2932/**
2933 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2934 * @clnt: pointer to struct rpc_clnt
2935 * @xps: pointer to struct rpc_xprt_switch,
2936 * @xprt: pointer struct rpc_xprt
2937 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport
2938 */
2939int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2940 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2941 void *in_max_connect)
2942{
2943 struct rpc_cb_add_xprt_calldata *data;
2944 struct rpc_task *task;
2945 int max_connect = clnt->cl_max_connect;
2946
2947 if (in_max_connect)
2948 max_connect = *(int *)in_max_connect;
2949 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) {
2950 rcu_read_lock();
2951 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2952 "transport to server: %s\n", max_connect,
2953 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2954 rcu_read_unlock();
2955 return -EINVAL;
2956 }
2957
2958 data = kmalloc(sizeof(*data), GFP_KERNEL);
2959 if (!data)
2960 return -ENOMEM;
2961 data->xps = xprt_switch_get(xps);
2962 data->xprt = xprt_get(xprt);
2963 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2964 rpc_cb_add_xprt_release(data);
2965 goto success;
2966 }
2967
2968 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2969 &rpc_cb_add_xprt_call_ops, data);
2970 if (IS_ERR(task))
2971 return PTR_ERR(task);
2972
2973 data->xps->xps_nunique_destaddr_xprts++;
2974 rpc_put_task(task);
2975success:
2976 return 1;
2977}
2978EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2979
2980static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2981 struct rpc_xprt *xprt,
2982 struct rpc_add_xprt_test *data)
2983{
2984 struct rpc_task *task;
2985 int status = -EADDRINUSE;
2986
2987 /* Test the connection */
2988 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2989 if (IS_ERR(task))
2990 return PTR_ERR(task);
2991
2992 status = task->tk_status;
2993 rpc_put_task(task);
2994
2995 if (status < 0)
2996 return status;
2997
2998 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2999 data->add_xprt_test(clnt, xprt, data->data);
3000
3001 return 0;
3002}
3003
3004/**
3005 * rpc_clnt_setup_test_and_add_xprt()
3006 *
3007 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
3008 * 1) caller of the test function must dereference the rpc_xprt_switch
3009 * and the rpc_xprt.
3010 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
3011 * the rpc_call_done routine.
3012 *
3013 * Upon success (return of 1), the test function adds the new
3014 * transport to the rpc_clnt xprt switch
3015 *
3016 * @clnt: struct rpc_clnt to get the new transport
3017 * @xps: the rpc_xprt_switch to hold the new transport
3018 * @xprt: the rpc_xprt to test
3019 * @data: a struct rpc_add_xprt_test pointer that holds the test function
3020 * and test function call data
3021 */
3022int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
3023 struct rpc_xprt_switch *xps,
3024 struct rpc_xprt *xprt,
3025 void *data)
3026{
3027 int status = -EADDRINUSE;
3028
3029 xprt = xprt_get(xprt);
3030 xprt_switch_get(xps);
3031
3032 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
3033 goto out_err;
3034
3035 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3036 if (status < 0)
3037 goto out_err;
3038
3039 status = 1;
3040out_err:
3041 xprt_put(xprt);
3042 xprt_switch_put(xps);
3043 if (status < 0)
3044 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3045 "added\n", status,
3046 xprt->address_strings[RPC_DISPLAY_ADDR]);
3047 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3048 return status;
3049}
3050EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3051
3052/**
3053 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3054 * @clnt: pointer to struct rpc_clnt
3055 * @xprtargs: pointer to struct xprt_create
3056 * @setup: callback to test and/or set up the connection
3057 * @data: pointer to setup function data
3058 *
3059 * Creates a new transport using the parameters set in args and
3060 * adds it to clnt.
3061 * If ping is set, then test that connectivity succeeds before
3062 * adding the new transport.
3063 *
3064 */
3065int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3066 struct xprt_create *xprtargs,
3067 int (*setup)(struct rpc_clnt *,
3068 struct rpc_xprt_switch *,
3069 struct rpc_xprt *,
3070 void *),
3071 void *data)
3072{
3073 struct rpc_xprt_switch *xps;
3074 struct rpc_xprt *xprt;
3075 unsigned long connect_timeout;
3076 unsigned long reconnect_timeout;
3077 unsigned char resvport, reuseport;
3078 int ret = 0, ident;
3079
3080 rcu_read_lock();
3081 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3082 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3083 if (xps == NULL || xprt == NULL) {
3084 rcu_read_unlock();
3085 xprt_switch_put(xps);
3086 return -EAGAIN;
3087 }
3088 resvport = xprt->resvport;
3089 reuseport = xprt->reuseport;
3090 connect_timeout = xprt->connect_timeout;
3091 reconnect_timeout = xprt->max_reconnect_timeout;
3092 ident = xprt->xprt_class->ident;
3093 rcu_read_unlock();
3094
3095 if (!xprtargs->ident)
3096 xprtargs->ident = ident;
3097 xprtargs->xprtsec = clnt->cl_xprtsec;
3098 xprt = xprt_create_transport(xprtargs);
3099 if (IS_ERR(xprt)) {
3100 ret = PTR_ERR(xprt);
3101 goto out_put_switch;
3102 }
3103 xprt->resvport = resvport;
3104 xprt->reuseport = reuseport;
3105
3106 if (xprtargs->connect_timeout)
3107 connect_timeout = xprtargs->connect_timeout;
3108 if (xprtargs->reconnect_timeout)
3109 reconnect_timeout = xprtargs->reconnect_timeout;
3110 if (xprt->ops->set_connect_timeout != NULL)
3111 xprt->ops->set_connect_timeout(xprt,
3112 connect_timeout,
3113 reconnect_timeout);
3114
3115 rpc_xprt_switch_set_roundrobin(xps);
3116 if (setup) {
3117 ret = setup(clnt, xps, xprt, data);
3118 if (ret != 0)
3119 goto out_put_xprt;
3120 }
3121 rpc_xprt_switch_add_xprt(xps, xprt);
3122out_put_xprt:
3123 xprt_put(xprt);
3124out_put_switch:
3125 xprt_switch_put(xps);
3126 return ret;
3127}
3128EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3129
3130static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3131 struct rpc_xprt *xprt,
3132 struct rpc_add_xprt_test *data)
3133{
3134 struct rpc_xprt *main_xprt;
3135 int status = 0;
3136
3137 xprt_get(xprt);
3138
3139 rcu_read_lock();
3140 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3141 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3142 (struct sockaddr *)&main_xprt->addr);
3143 rcu_read_unlock();
3144 xprt_put(main_xprt);
3145 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3146 goto out;
3147
3148 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3149out:
3150 xprt_put(xprt);
3151 return status;
3152}
3153
3154/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3155 * @clnt rpc_clnt structure
3156 *
3157 * For each offlined transport found in the rpc_clnt structure call
3158 * the function rpc_xprt_probe_trunked() which will determine if this
3159 * transport still belongs to the trunking group.
3160 */
3161void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3162 struct rpc_add_xprt_test *data)
3163{
3164 struct rpc_xprt_iter xpi;
3165 int ret;
3166
3167 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3168 if (ret)
3169 return;
3170 for (;;) {
3171 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3172
3173 if (!xprt)
3174 break;
3175 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3176 xprt_put(xprt);
3177 if (ret < 0)
3178 break;
3179 xprt_iter_rewind(&xpi);
3180 }
3181 xprt_iter_destroy(&xpi);
3182}
3183EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3184
3185static int rpc_xprt_offline(struct rpc_clnt *clnt,
3186 struct rpc_xprt *xprt,
3187 void *data)
3188{
3189 struct rpc_xprt *main_xprt;
3190 struct rpc_xprt_switch *xps;
3191 int err = 0;
3192
3193 xprt_get(xprt);
3194
3195 rcu_read_lock();
3196 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3197 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3198 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3199 (struct sockaddr *)&main_xprt->addr);
3200 rcu_read_unlock();
3201 xprt_put(main_xprt);
3202 if (err)
3203 goto out;
3204
3205 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3206 err = -EINTR;
3207 goto out;
3208 }
3209 xprt_set_offline_locked(xprt, xps);
3210
3211 xprt_release_write(xprt, NULL);
3212out:
3213 xprt_put(xprt);
3214 xprt_switch_put(xps);
3215 return err;
3216}
3217
3218/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3219 * @clnt rpc_clnt structure
3220 *
3221 * For each active transport found in the rpc_clnt structure call
3222 * the function rpc_xprt_offline() which will identify trunked transports
3223 * and will mark them offline.
3224 */
3225void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3226{
3227 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3228}
3229EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3230
3231struct connect_timeout_data {
3232 unsigned long connect_timeout;
3233 unsigned long reconnect_timeout;
3234};
3235
3236static int
3237rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3238 struct rpc_xprt *xprt,
3239 void *data)
3240{
3241 struct connect_timeout_data *timeo = data;
3242
3243 if (xprt->ops->set_connect_timeout)
3244 xprt->ops->set_connect_timeout(xprt,
3245 timeo->connect_timeout,
3246 timeo->reconnect_timeout);
3247 return 0;
3248}
3249
3250void
3251rpc_set_connect_timeout(struct rpc_clnt *clnt,
3252 unsigned long connect_timeout,
3253 unsigned long reconnect_timeout)
3254{
3255 struct connect_timeout_data timeout = {
3256 .connect_timeout = connect_timeout,
3257 .reconnect_timeout = reconnect_timeout,
3258 };
3259 rpc_clnt_iterate_for_each_xprt(clnt,
3260 rpc_xprt_set_connect_timeout,
3261 &timeout);
3262}
3263EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3264
3265void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3266{
3267 struct rpc_xprt_switch *xps;
3268
3269 xps = rpc_clnt_xprt_switch_get(clnt);
3270 xprt_set_online_locked(xprt, xps);
3271 xprt_switch_put(xps);
3272}
3273
3274void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3275{
3276 struct rpc_xprt_switch *xps;
3277
3278 if (rpc_clnt_xprt_switch_has_addr(clnt,
3279 (const struct sockaddr *)&xprt->addr)) {
3280 return rpc_clnt_xprt_set_online(clnt, xprt);
3281 }
3282
3283 xps = rpc_clnt_xprt_switch_get(clnt);
3284 rpc_xprt_switch_add_xprt(xps, xprt);
3285 xprt_switch_put(xps);
3286}
3287EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3288
3289void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3290{
3291 struct rpc_xprt_switch *xps;
3292
3293 rcu_read_lock();
3294 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3295 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3296 xprt, 0);
3297 xps->xps_nunique_destaddr_xprts--;
3298 rcu_read_unlock();
3299}
3300EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3301
3302bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3303 const struct sockaddr *sap)
3304{
3305 struct rpc_xprt_switch *xps;
3306 bool ret;
3307
3308 rcu_read_lock();
3309 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3310 ret = rpc_xprt_switch_has_addr(xps, sap);
3311 rcu_read_unlock();
3312 return ret;
3313}
3314EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3315
3316#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3317static void rpc_show_header(void)
3318{
3319 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3320 "-timeout ---ops--\n");
3321}
3322
3323static void rpc_show_task(const struct rpc_clnt *clnt,
3324 const struct rpc_task *task)
3325{
3326 const char *rpc_waitq = "none";
3327
3328 if (RPC_IS_QUEUED(task))
3329 rpc_waitq = rpc_qname(task->tk_waitqueue);
3330
3331 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3332 task->tk_pid, task->tk_flags, task->tk_status,
3333 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3334 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3335 task->tk_action, rpc_waitq);
3336}
3337
3338void rpc_show_tasks(struct net *net)
3339{
3340 struct rpc_clnt *clnt;
3341 struct rpc_task *task;
3342 int header = 0;
3343 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3344
3345 spin_lock(&sn->rpc_client_lock);
3346 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3347 spin_lock(&clnt->cl_lock);
3348 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3349 if (!header) {
3350 rpc_show_header();
3351 header++;
3352 }
3353 rpc_show_task(clnt, task);
3354 }
3355 spin_unlock(&clnt->cl_lock);
3356 }
3357 spin_unlock(&sn->rpc_client_lock);
3358}
3359#endif
3360
3361#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3362static int
3363rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3364 struct rpc_xprt *xprt,
3365 void *dummy)
3366{
3367 return xprt_enable_swap(xprt);
3368}
3369
3370int
3371rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3372{
3373 while (clnt != clnt->cl_parent)
3374 clnt = clnt->cl_parent;
3375 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3376 return rpc_clnt_iterate_for_each_xprt(clnt,
3377 rpc_clnt_swap_activate_callback, NULL);
3378 return 0;
3379}
3380EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3381
3382static int
3383rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3384 struct rpc_xprt *xprt,
3385 void *dummy)
3386{
3387 xprt_disable_swap(xprt);
3388 return 0;
3389}
3390
3391void
3392rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3393{
3394 while (clnt != clnt->cl_parent)
3395 clnt = clnt->cl_parent;
3396 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3397 rpc_clnt_iterate_for_each_xprt(clnt,
3398 rpc_clnt_swap_deactivate_callback, NULL);
3399}
3400EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3401#endif /* CONFIG_SUNRPC_SWAP */
1/*
2 * linux/net/sunrpc/clnt.c
3 *
4 * This file contains the high-level RPC interface.
5 * It is modeled as a finite state machine to support both synchronous
6 * and asynchronous requests.
7 *
8 * - RPC header generation and argument serialization.
9 * - Credential refresh.
10 * - TCP connect handling.
11 * - Retry of operation when it is suspected the operation failed because
12 * of uid squashing on the server, or when the credentials were stale
13 * and need to be refreshed, or when a packet was damaged in transit.
14 * This may be have to be moved to the VFS layer.
15 *
16 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
17 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
18 */
19
20#include <asm/system.h>
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.h>
29#include <linux/utsname.h>
30#include <linux/workqueue.h>
31#include <linux/in.h>
32#include <linux/in6.h>
33#include <linux/un.h>
34
35#include <linux/sunrpc/clnt.h>
36#include <linux/sunrpc/rpc_pipe_fs.h>
37#include <linux/sunrpc/metrics.h>
38#include <linux/sunrpc/bc_xprt.h>
39
40#include "sunrpc.h"
41
42#ifdef RPC_DEBUG
43# define RPCDBG_FACILITY RPCDBG_CALL
44#endif
45
46#define dprint_status(t) \
47 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
48 __func__, t->tk_status)
49
50/*
51 * All RPC clients are linked into this list
52 */
53static LIST_HEAD(all_clients);
54static DEFINE_SPINLOCK(rpc_client_lock);
55
56static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
57
58
59static void call_start(struct rpc_task *task);
60static void call_reserve(struct rpc_task *task);
61static void call_reserveresult(struct rpc_task *task);
62static void call_allocate(struct rpc_task *task);
63static void call_decode(struct rpc_task *task);
64static void call_bind(struct rpc_task *task);
65static void call_bind_status(struct rpc_task *task);
66static void call_transmit(struct rpc_task *task);
67#if defined(CONFIG_SUNRPC_BACKCHANNEL)
68static void call_bc_transmit(struct rpc_task *task);
69#endif /* CONFIG_SUNRPC_BACKCHANNEL */
70static void call_status(struct rpc_task *task);
71static void call_transmit_status(struct rpc_task *task);
72static void call_refresh(struct rpc_task *task);
73static void call_refreshresult(struct rpc_task *task);
74static void call_timeout(struct rpc_task *task);
75static void call_connect(struct rpc_task *task);
76static void call_connect_status(struct rpc_task *task);
77
78static __be32 *rpc_encode_header(struct rpc_task *task);
79static __be32 *rpc_verify_header(struct rpc_task *task);
80static int rpc_ping(struct rpc_clnt *clnt);
81
82static void rpc_register_client(struct rpc_clnt *clnt)
83{
84 spin_lock(&rpc_client_lock);
85 list_add(&clnt->cl_clients, &all_clients);
86 spin_unlock(&rpc_client_lock);
87}
88
89static void rpc_unregister_client(struct rpc_clnt *clnt)
90{
91 spin_lock(&rpc_client_lock);
92 list_del(&clnt->cl_clients);
93 spin_unlock(&rpc_client_lock);
94}
95
96static int
97rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
98{
99 static uint32_t clntid;
100 struct path path, dir;
101 char name[15];
102 struct qstr q = {
103 .name = name,
104 };
105 int error;
106
107 clnt->cl_path.mnt = ERR_PTR(-ENOENT);
108 clnt->cl_path.dentry = ERR_PTR(-ENOENT);
109 if (dir_name == NULL)
110 return 0;
111
112 path.mnt = rpc_get_mount();
113 if (IS_ERR(path.mnt))
114 return PTR_ERR(path.mnt);
115 error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &dir);
116 if (error)
117 goto err;
118
119 for (;;) {
120 q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
121 name[sizeof(name) - 1] = '\0';
122 q.hash = full_name_hash(q.name, q.len);
123 path.dentry = rpc_create_client_dir(dir.dentry, &q, clnt);
124 if (!IS_ERR(path.dentry))
125 break;
126 error = PTR_ERR(path.dentry);
127 if (error != -EEXIST) {
128 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
129 " %s/%s, error %d\n",
130 dir_name, name, error);
131 goto err_path_put;
132 }
133 }
134 path_put(&dir);
135 clnt->cl_path = path;
136 return 0;
137err_path_put:
138 path_put(&dir);
139err:
140 rpc_put_mount();
141 return error;
142}
143
144static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
145{
146 struct rpc_program *program = args->program;
147 struct rpc_version *version;
148 struct rpc_clnt *clnt = NULL;
149 struct rpc_auth *auth;
150 int err;
151 size_t len;
152
153 /* sanity check the name before trying to print it */
154 err = -EINVAL;
155 len = strlen(args->servername);
156 if (len > RPC_MAXNETNAMELEN)
157 goto out_no_rpciod;
158 len++;
159
160 dprintk("RPC: creating %s client for %s (xprt %p)\n",
161 program->name, args->servername, xprt);
162
163 err = rpciod_up();
164 if (err)
165 goto out_no_rpciod;
166 err = -EINVAL;
167 if (!xprt)
168 goto out_no_xprt;
169
170 if (args->version >= program->nrvers)
171 goto out_err;
172 version = program->version[args->version];
173 if (version == NULL)
174 goto out_err;
175
176 err = -ENOMEM;
177 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
178 if (!clnt)
179 goto out_err;
180 clnt->cl_parent = clnt;
181
182 clnt->cl_server = clnt->cl_inline_name;
183 if (len > sizeof(clnt->cl_inline_name)) {
184 char *buf = kmalloc(len, GFP_KERNEL);
185 if (buf != NULL)
186 clnt->cl_server = buf;
187 else
188 len = sizeof(clnt->cl_inline_name);
189 }
190 strlcpy(clnt->cl_server, args->servername, len);
191
192 clnt->cl_xprt = xprt;
193 clnt->cl_procinfo = version->procs;
194 clnt->cl_maxproc = version->nrprocs;
195 clnt->cl_protname = program->name;
196 clnt->cl_prog = args->prognumber ? : program->number;
197 clnt->cl_vers = version->number;
198 clnt->cl_stats = program->stats;
199 clnt->cl_metrics = rpc_alloc_iostats(clnt);
200 err = -ENOMEM;
201 if (clnt->cl_metrics == NULL)
202 goto out_no_stats;
203 clnt->cl_program = program;
204 INIT_LIST_HEAD(&clnt->cl_tasks);
205 spin_lock_init(&clnt->cl_lock);
206
207 if (!xprt_bound(clnt->cl_xprt))
208 clnt->cl_autobind = 1;
209
210 clnt->cl_timeout = xprt->timeout;
211 if (args->timeout != NULL) {
212 memcpy(&clnt->cl_timeout_default, args->timeout,
213 sizeof(clnt->cl_timeout_default));
214 clnt->cl_timeout = &clnt->cl_timeout_default;
215 }
216
217 clnt->cl_rtt = &clnt->cl_rtt_default;
218 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
219 clnt->cl_principal = NULL;
220 if (args->client_name) {
221 clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
222 if (!clnt->cl_principal)
223 goto out_no_principal;
224 }
225
226 atomic_set(&clnt->cl_count, 1);
227
228 err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
229 if (err < 0)
230 goto out_no_path;
231
232 auth = rpcauth_create(args->authflavor, clnt);
233 if (IS_ERR(auth)) {
234 printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
235 args->authflavor);
236 err = PTR_ERR(auth);
237 goto out_no_auth;
238 }
239
240 /* save the nodename */
241 clnt->cl_nodelen = strlen(init_utsname()->nodename);
242 if (clnt->cl_nodelen > UNX_MAXNODENAME)
243 clnt->cl_nodelen = UNX_MAXNODENAME;
244 memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen);
245 rpc_register_client(clnt);
246 return clnt;
247
248out_no_auth:
249 if (!IS_ERR(clnt->cl_path.dentry)) {
250 rpc_remove_client_dir(clnt->cl_path.dentry);
251 rpc_put_mount();
252 }
253out_no_path:
254 kfree(clnt->cl_principal);
255out_no_principal:
256 rpc_free_iostats(clnt->cl_metrics);
257out_no_stats:
258 if (clnt->cl_server != clnt->cl_inline_name)
259 kfree(clnt->cl_server);
260 kfree(clnt);
261out_err:
262 xprt_put(xprt);
263out_no_xprt:
264 rpciod_down();
265out_no_rpciod:
266 return ERR_PTR(err);
267}
268
269/*
270 * rpc_create - create an RPC client and transport with one call
271 * @args: rpc_clnt create argument structure
272 *
273 * Creates and initializes an RPC transport and an RPC client.
274 *
275 * It can ping the server in order to determine if it is up, and to see if
276 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
277 * this behavior so asynchronous tasks can also use rpc_create.
278 */
279struct rpc_clnt *rpc_create(struct rpc_create_args *args)
280{
281 struct rpc_xprt *xprt;
282 struct rpc_clnt *clnt;
283 struct xprt_create xprtargs = {
284 .net = args->net,
285 .ident = args->protocol,
286 .srcaddr = args->saddress,
287 .dstaddr = args->address,
288 .addrlen = args->addrsize,
289 .bc_xprt = args->bc_xprt,
290 };
291 char servername[48];
292
293 /*
294 * If the caller chooses not to specify a hostname, whip
295 * up a string representation of the passed-in address.
296 */
297 if (args->servername == NULL) {
298 struct sockaddr_un *sun =
299 (struct sockaddr_un *)args->address;
300 struct sockaddr_in *sin =
301 (struct sockaddr_in *)args->address;
302 struct sockaddr_in6 *sin6 =
303 (struct sockaddr_in6 *)args->address;
304
305 servername[0] = '\0';
306 switch (args->address->sa_family) {
307 case AF_LOCAL:
308 snprintf(servername, sizeof(servername), "%s",
309 sun->sun_path);
310 break;
311 case AF_INET:
312 snprintf(servername, sizeof(servername), "%pI4",
313 &sin->sin_addr.s_addr);
314 break;
315 case AF_INET6:
316 snprintf(servername, sizeof(servername), "%pI6",
317 &sin6->sin6_addr);
318 break;
319 default:
320 /* caller wants default server name, but
321 * address family isn't recognized. */
322 return ERR_PTR(-EINVAL);
323 }
324 args->servername = servername;
325 }
326
327 xprt = xprt_create_transport(&xprtargs);
328 if (IS_ERR(xprt))
329 return (struct rpc_clnt *)xprt;
330
331 /*
332 * By default, kernel RPC client connects from a reserved port.
333 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
334 * but it is always enabled for rpciod, which handles the connect
335 * operation.
336 */
337 xprt->resvport = 1;
338 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
339 xprt->resvport = 0;
340
341 clnt = rpc_new_client(args, xprt);
342 if (IS_ERR(clnt))
343 return clnt;
344
345 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
346 int err = rpc_ping(clnt);
347 if (err != 0) {
348 rpc_shutdown_client(clnt);
349 return ERR_PTR(err);
350 }
351 }
352
353 clnt->cl_softrtry = 1;
354 if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
355 clnt->cl_softrtry = 0;
356
357 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
358 clnt->cl_autobind = 1;
359 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
360 clnt->cl_discrtry = 1;
361 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
362 clnt->cl_chatty = 1;
363
364 return clnt;
365}
366EXPORT_SYMBOL_GPL(rpc_create);
367
368/*
369 * This function clones the RPC client structure. It allows us to share the
370 * same transport while varying parameters such as the authentication
371 * flavour.
372 */
373struct rpc_clnt *
374rpc_clone_client(struct rpc_clnt *clnt)
375{
376 struct rpc_clnt *new;
377 int err = -ENOMEM;
378
379 new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
380 if (!new)
381 goto out_no_clnt;
382 new->cl_parent = clnt;
383 /* Turn off autobind on clones */
384 new->cl_autobind = 0;
385 INIT_LIST_HEAD(&new->cl_tasks);
386 spin_lock_init(&new->cl_lock);
387 rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
388 new->cl_metrics = rpc_alloc_iostats(clnt);
389 if (new->cl_metrics == NULL)
390 goto out_no_stats;
391 if (clnt->cl_principal) {
392 new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
393 if (new->cl_principal == NULL)
394 goto out_no_principal;
395 }
396 atomic_set(&new->cl_count, 1);
397 err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
398 if (err != 0)
399 goto out_no_path;
400 if (new->cl_auth)
401 atomic_inc(&new->cl_auth->au_count);
402 xprt_get(clnt->cl_xprt);
403 atomic_inc(&clnt->cl_count);
404 rpc_register_client(new);
405 rpciod_up();
406 return new;
407out_no_path:
408 kfree(new->cl_principal);
409out_no_principal:
410 rpc_free_iostats(new->cl_metrics);
411out_no_stats:
412 kfree(new);
413out_no_clnt:
414 dprintk("RPC: %s: returned error %d\n", __func__, err);
415 return ERR_PTR(err);
416}
417EXPORT_SYMBOL_GPL(rpc_clone_client);
418
419/*
420 * Kill all tasks for the given client.
421 * XXX: kill their descendants as well?
422 */
423void rpc_killall_tasks(struct rpc_clnt *clnt)
424{
425 struct rpc_task *rovr;
426
427
428 if (list_empty(&clnt->cl_tasks))
429 return;
430 dprintk("RPC: killing all tasks for client %p\n", clnt);
431 /*
432 * Spin lock all_tasks to prevent changes...
433 */
434 spin_lock(&clnt->cl_lock);
435 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
436 if (!RPC_IS_ACTIVATED(rovr))
437 continue;
438 if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
439 rovr->tk_flags |= RPC_TASK_KILLED;
440 rpc_exit(rovr, -EIO);
441 if (RPC_IS_QUEUED(rovr))
442 rpc_wake_up_queued_task(rovr->tk_waitqueue,
443 rovr);
444 }
445 }
446 spin_unlock(&clnt->cl_lock);
447}
448EXPORT_SYMBOL_GPL(rpc_killall_tasks);
449
450/*
451 * Properly shut down an RPC client, terminating all outstanding
452 * requests.
453 */
454void rpc_shutdown_client(struct rpc_clnt *clnt)
455{
456 dprintk("RPC: shutting down %s client for %s\n",
457 clnt->cl_protname, clnt->cl_server);
458
459 while (!list_empty(&clnt->cl_tasks)) {
460 rpc_killall_tasks(clnt);
461 wait_event_timeout(destroy_wait,
462 list_empty(&clnt->cl_tasks), 1*HZ);
463 }
464
465 rpc_release_client(clnt);
466}
467EXPORT_SYMBOL_GPL(rpc_shutdown_client);
468
469/*
470 * Free an RPC client
471 */
472static void
473rpc_free_client(struct rpc_clnt *clnt)
474{
475 dprintk("RPC: destroying %s client for %s\n",
476 clnt->cl_protname, clnt->cl_server);
477 if (!IS_ERR(clnt->cl_path.dentry)) {
478 rpc_remove_client_dir(clnt->cl_path.dentry);
479 rpc_put_mount();
480 }
481 if (clnt->cl_parent != clnt) {
482 rpc_release_client(clnt->cl_parent);
483 goto out_free;
484 }
485 if (clnt->cl_server != clnt->cl_inline_name)
486 kfree(clnt->cl_server);
487out_free:
488 rpc_unregister_client(clnt);
489 rpc_free_iostats(clnt->cl_metrics);
490 kfree(clnt->cl_principal);
491 clnt->cl_metrics = NULL;
492 xprt_put(clnt->cl_xprt);
493 rpciod_down();
494 kfree(clnt);
495}
496
497/*
498 * Free an RPC client
499 */
500static void
501rpc_free_auth(struct rpc_clnt *clnt)
502{
503 if (clnt->cl_auth == NULL) {
504 rpc_free_client(clnt);
505 return;
506 }
507
508 /*
509 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
510 * release remaining GSS contexts. This mechanism ensures
511 * that it can do so safely.
512 */
513 atomic_inc(&clnt->cl_count);
514 rpcauth_release(clnt->cl_auth);
515 clnt->cl_auth = NULL;
516 if (atomic_dec_and_test(&clnt->cl_count))
517 rpc_free_client(clnt);
518}
519
520/*
521 * Release reference to the RPC client
522 */
523void
524rpc_release_client(struct rpc_clnt *clnt)
525{
526 dprintk("RPC: rpc_release_client(%p)\n", clnt);
527
528 if (list_empty(&clnt->cl_tasks))
529 wake_up(&destroy_wait);
530 if (atomic_dec_and_test(&clnt->cl_count))
531 rpc_free_auth(clnt);
532}
533
534/**
535 * rpc_bind_new_program - bind a new RPC program to an existing client
536 * @old: old rpc_client
537 * @program: rpc program to set
538 * @vers: rpc program version
539 *
540 * Clones the rpc client and sets up a new RPC program. This is mainly
541 * of use for enabling different RPC programs to share the same transport.
542 * The Sun NFSv2/v3 ACL protocol can do this.
543 */
544struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
545 struct rpc_program *program,
546 u32 vers)
547{
548 struct rpc_clnt *clnt;
549 struct rpc_version *version;
550 int err;
551
552 BUG_ON(vers >= program->nrvers || !program->version[vers]);
553 version = program->version[vers];
554 clnt = rpc_clone_client(old);
555 if (IS_ERR(clnt))
556 goto out;
557 clnt->cl_procinfo = version->procs;
558 clnt->cl_maxproc = version->nrprocs;
559 clnt->cl_protname = program->name;
560 clnt->cl_prog = program->number;
561 clnt->cl_vers = version->number;
562 clnt->cl_stats = program->stats;
563 err = rpc_ping(clnt);
564 if (err != 0) {
565 rpc_shutdown_client(clnt);
566 clnt = ERR_PTR(err);
567 }
568out:
569 return clnt;
570}
571EXPORT_SYMBOL_GPL(rpc_bind_new_program);
572
573void rpc_task_release_client(struct rpc_task *task)
574{
575 struct rpc_clnt *clnt = task->tk_client;
576
577 if (clnt != NULL) {
578 /* Remove from client task list */
579 spin_lock(&clnt->cl_lock);
580 list_del(&task->tk_task);
581 spin_unlock(&clnt->cl_lock);
582 task->tk_client = NULL;
583
584 rpc_release_client(clnt);
585 }
586}
587
588static
589void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
590{
591 if (clnt != NULL) {
592 rpc_task_release_client(task);
593 task->tk_client = clnt;
594 atomic_inc(&clnt->cl_count);
595 if (clnt->cl_softrtry)
596 task->tk_flags |= RPC_TASK_SOFT;
597 /* Add to the client's list of all tasks */
598 spin_lock(&clnt->cl_lock);
599 list_add_tail(&task->tk_task, &clnt->cl_tasks);
600 spin_unlock(&clnt->cl_lock);
601 }
602}
603
604void rpc_task_reset_client(struct rpc_task *task, struct rpc_clnt *clnt)
605{
606 rpc_task_release_client(task);
607 rpc_task_set_client(task, clnt);
608}
609EXPORT_SYMBOL_GPL(rpc_task_reset_client);
610
611
612static void
613rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
614{
615 if (msg != NULL) {
616 task->tk_msg.rpc_proc = msg->rpc_proc;
617 task->tk_msg.rpc_argp = msg->rpc_argp;
618 task->tk_msg.rpc_resp = msg->rpc_resp;
619 if (msg->rpc_cred != NULL)
620 task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
621 }
622}
623
624/*
625 * Default callback for async RPC calls
626 */
627static void
628rpc_default_callback(struct rpc_task *task, void *data)
629{
630}
631
632static const struct rpc_call_ops rpc_default_ops = {
633 .rpc_call_done = rpc_default_callback,
634};
635
636/**
637 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
638 * @task_setup_data: pointer to task initialisation data
639 */
640struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
641{
642 struct rpc_task *task;
643
644 task = rpc_new_task(task_setup_data);
645 if (IS_ERR(task))
646 goto out;
647
648 rpc_task_set_client(task, task_setup_data->rpc_client);
649 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
650
651 if (task->tk_action == NULL)
652 rpc_call_start(task);
653
654 atomic_inc(&task->tk_count);
655 rpc_execute(task);
656out:
657 return task;
658}
659EXPORT_SYMBOL_GPL(rpc_run_task);
660
661/**
662 * rpc_call_sync - Perform a synchronous RPC call
663 * @clnt: pointer to RPC client
664 * @msg: RPC call parameters
665 * @flags: RPC call flags
666 */
667int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
668{
669 struct rpc_task *task;
670 struct rpc_task_setup task_setup_data = {
671 .rpc_client = clnt,
672 .rpc_message = msg,
673 .callback_ops = &rpc_default_ops,
674 .flags = flags,
675 };
676 int status;
677
678 BUG_ON(flags & RPC_TASK_ASYNC);
679
680 task = rpc_run_task(&task_setup_data);
681 if (IS_ERR(task))
682 return PTR_ERR(task);
683 status = task->tk_status;
684 rpc_put_task(task);
685 return status;
686}
687EXPORT_SYMBOL_GPL(rpc_call_sync);
688
689/**
690 * rpc_call_async - Perform an asynchronous RPC call
691 * @clnt: pointer to RPC client
692 * @msg: RPC call parameters
693 * @flags: RPC call flags
694 * @tk_ops: RPC call ops
695 * @data: user call data
696 */
697int
698rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
699 const struct rpc_call_ops *tk_ops, void *data)
700{
701 struct rpc_task *task;
702 struct rpc_task_setup task_setup_data = {
703 .rpc_client = clnt,
704 .rpc_message = msg,
705 .callback_ops = tk_ops,
706 .callback_data = data,
707 .flags = flags|RPC_TASK_ASYNC,
708 };
709
710 task = rpc_run_task(&task_setup_data);
711 if (IS_ERR(task))
712 return PTR_ERR(task);
713 rpc_put_task(task);
714 return 0;
715}
716EXPORT_SYMBOL_GPL(rpc_call_async);
717
718#if defined(CONFIG_SUNRPC_BACKCHANNEL)
719/**
720 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
721 * rpc_execute against it
722 * @req: RPC request
723 * @tk_ops: RPC call ops
724 */
725struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
726 const struct rpc_call_ops *tk_ops)
727{
728 struct rpc_task *task;
729 struct xdr_buf *xbufp = &req->rq_snd_buf;
730 struct rpc_task_setup task_setup_data = {
731 .callback_ops = tk_ops,
732 };
733
734 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
735 /*
736 * Create an rpc_task to send the data
737 */
738 task = rpc_new_task(&task_setup_data);
739 if (IS_ERR(task)) {
740 xprt_free_bc_request(req);
741 goto out;
742 }
743 task->tk_rqstp = req;
744
745 /*
746 * Set up the xdr_buf length.
747 * This also indicates that the buffer is XDR encoded already.
748 */
749 xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
750 xbufp->tail[0].iov_len;
751
752 task->tk_action = call_bc_transmit;
753 atomic_inc(&task->tk_count);
754 BUG_ON(atomic_read(&task->tk_count) != 2);
755 rpc_execute(task);
756
757out:
758 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
759 return task;
760}
761#endif /* CONFIG_SUNRPC_BACKCHANNEL */
762
763void
764rpc_call_start(struct rpc_task *task)
765{
766 task->tk_action = call_start;
767}
768EXPORT_SYMBOL_GPL(rpc_call_start);
769
770/**
771 * rpc_peeraddr - extract remote peer address from clnt's xprt
772 * @clnt: RPC client structure
773 * @buf: target buffer
774 * @bufsize: length of target buffer
775 *
776 * Returns the number of bytes that are actually in the stored address.
777 */
778size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
779{
780 size_t bytes;
781 struct rpc_xprt *xprt = clnt->cl_xprt;
782
783 bytes = sizeof(xprt->addr);
784 if (bytes > bufsize)
785 bytes = bufsize;
786 memcpy(buf, &clnt->cl_xprt->addr, bytes);
787 return xprt->addrlen;
788}
789EXPORT_SYMBOL_GPL(rpc_peeraddr);
790
791/**
792 * rpc_peeraddr2str - return remote peer address in printable format
793 * @clnt: RPC client structure
794 * @format: address format
795 *
796 */
797const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
798 enum rpc_display_format_t format)
799{
800 struct rpc_xprt *xprt = clnt->cl_xprt;
801
802 if (xprt->address_strings[format] != NULL)
803 return xprt->address_strings[format];
804 else
805 return "unprintable";
806}
807EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
808
809void
810rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
811{
812 struct rpc_xprt *xprt = clnt->cl_xprt;
813 if (xprt->ops->set_buffer_size)
814 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
815}
816EXPORT_SYMBOL_GPL(rpc_setbufsize);
817
818/*
819 * Return size of largest payload RPC client can support, in bytes
820 *
821 * For stream transports, this is one RPC record fragment (see RFC
822 * 1831), as we don't support multi-record requests yet. For datagram
823 * transports, this is the size of an IP packet minus the IP, UDP, and
824 * RPC header sizes.
825 */
826size_t rpc_max_payload(struct rpc_clnt *clnt)
827{
828 return clnt->cl_xprt->max_payload;
829}
830EXPORT_SYMBOL_GPL(rpc_max_payload);
831
832/**
833 * rpc_force_rebind - force transport to check that remote port is unchanged
834 * @clnt: client to rebind
835 *
836 */
837void rpc_force_rebind(struct rpc_clnt *clnt)
838{
839 if (clnt->cl_autobind)
840 xprt_clear_bound(clnt->cl_xprt);
841}
842EXPORT_SYMBOL_GPL(rpc_force_rebind);
843
844/*
845 * Restart an (async) RPC call from the call_prepare state.
846 * Usually called from within the exit handler.
847 */
848int
849rpc_restart_call_prepare(struct rpc_task *task)
850{
851 if (RPC_ASSASSINATED(task))
852 return 0;
853 task->tk_action = rpc_prepare_task;
854 return 1;
855}
856EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
857
858/*
859 * Restart an (async) RPC call. Usually called from within the
860 * exit handler.
861 */
862int
863rpc_restart_call(struct rpc_task *task)
864{
865 if (RPC_ASSASSINATED(task))
866 return 0;
867 task->tk_action = call_start;
868 return 1;
869}
870EXPORT_SYMBOL_GPL(rpc_restart_call);
871
872#ifdef RPC_DEBUG
873static const char *rpc_proc_name(const struct rpc_task *task)
874{
875 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
876
877 if (proc) {
878 if (proc->p_name)
879 return proc->p_name;
880 else
881 return "NULL";
882 } else
883 return "no proc";
884}
885#endif
886
887/*
888 * 0. Initial state
889 *
890 * Other FSM states can be visited zero or more times, but
891 * this state is visited exactly once for each RPC.
892 */
893static void
894call_start(struct rpc_task *task)
895{
896 struct rpc_clnt *clnt = task->tk_client;
897
898 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
899 clnt->cl_protname, clnt->cl_vers,
900 rpc_proc_name(task),
901 (RPC_IS_ASYNC(task) ? "async" : "sync"));
902
903 /* Increment call count */
904 task->tk_msg.rpc_proc->p_count++;
905 clnt->cl_stats->rpccnt++;
906 task->tk_action = call_reserve;
907}
908
909/*
910 * 1. Reserve an RPC call slot
911 */
912static void
913call_reserve(struct rpc_task *task)
914{
915 dprint_status(task);
916
917 task->tk_status = 0;
918 task->tk_action = call_reserveresult;
919 xprt_reserve(task);
920}
921
922/*
923 * 1b. Grok the result of xprt_reserve()
924 */
925static void
926call_reserveresult(struct rpc_task *task)
927{
928 int status = task->tk_status;
929
930 dprint_status(task);
931
932 /*
933 * After a call to xprt_reserve(), we must have either
934 * a request slot or else an error status.
935 */
936 task->tk_status = 0;
937 if (status >= 0) {
938 if (task->tk_rqstp) {
939 task->tk_action = call_refresh;
940 return;
941 }
942
943 printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
944 __func__, status);
945 rpc_exit(task, -EIO);
946 return;
947 }
948
949 /*
950 * Even though there was an error, we may have acquired
951 * a request slot somehow. Make sure not to leak it.
952 */
953 if (task->tk_rqstp) {
954 printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
955 __func__, status);
956 xprt_release(task);
957 }
958
959 switch (status) {
960 case -EAGAIN: /* woken up; retry */
961 task->tk_action = call_reserve;
962 return;
963 case -EIO: /* probably a shutdown */
964 break;
965 default:
966 printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
967 __func__, status);
968 break;
969 }
970 rpc_exit(task, status);
971}
972
973/*
974 * 2. Bind and/or refresh the credentials
975 */
976static void
977call_refresh(struct rpc_task *task)
978{
979 dprint_status(task);
980
981 task->tk_action = call_refreshresult;
982 task->tk_status = 0;
983 task->tk_client->cl_stats->rpcauthrefresh++;
984 rpcauth_refreshcred(task);
985}
986
987/*
988 * 2a. Process the results of a credential refresh
989 */
990static void
991call_refreshresult(struct rpc_task *task)
992{
993 int status = task->tk_status;
994
995 dprint_status(task);
996
997 task->tk_status = 0;
998 task->tk_action = call_refresh;
999 switch (status) {
1000 case 0:
1001 if (rpcauth_uptodatecred(task))
1002 task->tk_action = call_allocate;
1003 return;
1004 case -ETIMEDOUT:
1005 rpc_delay(task, 3*HZ);
1006 case -EAGAIN:
1007 status = -EACCES;
1008 if (!task->tk_cred_retry)
1009 break;
1010 task->tk_cred_retry--;
1011 dprintk("RPC: %5u %s: retry refresh creds\n",
1012 task->tk_pid, __func__);
1013 return;
1014 }
1015 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1016 task->tk_pid, __func__, status);
1017 rpc_exit(task, status);
1018}
1019
1020/*
1021 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1022 * (Note: buffer memory is freed in xprt_release).
1023 */
1024static void
1025call_allocate(struct rpc_task *task)
1026{
1027 unsigned int slack = task->tk_rqstp->rq_cred->cr_auth->au_cslack;
1028 struct rpc_rqst *req = task->tk_rqstp;
1029 struct rpc_xprt *xprt = task->tk_xprt;
1030 struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1031
1032 dprint_status(task);
1033
1034 task->tk_status = 0;
1035 task->tk_action = call_bind;
1036
1037 if (req->rq_buffer)
1038 return;
1039
1040 if (proc->p_proc != 0) {
1041 BUG_ON(proc->p_arglen == 0);
1042 if (proc->p_decode != NULL)
1043 BUG_ON(proc->p_replen == 0);
1044 }
1045
1046 /*
1047 * Calculate the size (in quads) of the RPC call
1048 * and reply headers, and convert both values
1049 * to byte sizes.
1050 */
1051 req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
1052 req->rq_callsize <<= 2;
1053 req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
1054 req->rq_rcvsize <<= 2;
1055
1056 req->rq_buffer = xprt->ops->buf_alloc(task,
1057 req->rq_callsize + req->rq_rcvsize);
1058 if (req->rq_buffer != NULL)
1059 return;
1060
1061 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1062
1063 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1064 task->tk_action = call_allocate;
1065 rpc_delay(task, HZ>>4);
1066 return;
1067 }
1068
1069 rpc_exit(task, -ERESTARTSYS);
1070}
1071
1072static inline int
1073rpc_task_need_encode(struct rpc_task *task)
1074{
1075 return task->tk_rqstp->rq_snd_buf.len == 0;
1076}
1077
1078static inline void
1079rpc_task_force_reencode(struct rpc_task *task)
1080{
1081 task->tk_rqstp->rq_snd_buf.len = 0;
1082 task->tk_rqstp->rq_bytes_sent = 0;
1083}
1084
1085static inline void
1086rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
1087{
1088 buf->head[0].iov_base = start;
1089 buf->head[0].iov_len = len;
1090 buf->tail[0].iov_len = 0;
1091 buf->page_len = 0;
1092 buf->flags = 0;
1093 buf->len = 0;
1094 buf->buflen = len;
1095}
1096
1097/*
1098 * 3. Encode arguments of an RPC call
1099 */
1100static void
1101rpc_xdr_encode(struct rpc_task *task)
1102{
1103 struct rpc_rqst *req = task->tk_rqstp;
1104 kxdreproc_t encode;
1105 __be32 *p;
1106
1107 dprint_status(task);
1108
1109 rpc_xdr_buf_init(&req->rq_snd_buf,
1110 req->rq_buffer,
1111 req->rq_callsize);
1112 rpc_xdr_buf_init(&req->rq_rcv_buf,
1113 (char *)req->rq_buffer + req->rq_callsize,
1114 req->rq_rcvsize);
1115
1116 p = rpc_encode_header(task);
1117 if (p == NULL) {
1118 printk(KERN_INFO "RPC: couldn't encode RPC header, exit EIO\n");
1119 rpc_exit(task, -EIO);
1120 return;
1121 }
1122
1123 encode = task->tk_msg.rpc_proc->p_encode;
1124 if (encode == NULL)
1125 return;
1126
1127 task->tk_status = rpcauth_wrap_req(task, encode, req, p,
1128 task->tk_msg.rpc_argp);
1129}
1130
1131/*
1132 * 4. Get the server port number if not yet set
1133 */
1134static void
1135call_bind(struct rpc_task *task)
1136{
1137 struct rpc_xprt *xprt = task->tk_xprt;
1138
1139 dprint_status(task);
1140
1141 task->tk_action = call_connect;
1142 if (!xprt_bound(xprt)) {
1143 task->tk_action = call_bind_status;
1144 task->tk_timeout = xprt->bind_timeout;
1145 xprt->ops->rpcbind(task);
1146 }
1147}
1148
1149/*
1150 * 4a. Sort out bind result
1151 */
1152static void
1153call_bind_status(struct rpc_task *task)
1154{
1155 int status = -EIO;
1156
1157 if (task->tk_status >= 0) {
1158 dprint_status(task);
1159 task->tk_status = 0;
1160 task->tk_action = call_connect;
1161 return;
1162 }
1163
1164 switch (task->tk_status) {
1165 case -ENOMEM:
1166 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1167 rpc_delay(task, HZ >> 2);
1168 goto retry_timeout;
1169 case -EACCES:
1170 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1171 "unavailable\n", task->tk_pid);
1172 /* fail immediately if this is an RPC ping */
1173 if (task->tk_msg.rpc_proc->p_proc == 0) {
1174 status = -EOPNOTSUPP;
1175 break;
1176 }
1177 if (task->tk_rebind_retry == 0)
1178 break;
1179 task->tk_rebind_retry--;
1180 rpc_delay(task, 3*HZ);
1181 goto retry_timeout;
1182 case -ETIMEDOUT:
1183 dprintk("RPC: %5u rpcbind request timed out\n",
1184 task->tk_pid);
1185 goto retry_timeout;
1186 case -EPFNOSUPPORT:
1187 /* server doesn't support any rpcbind version we know of */
1188 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
1189 task->tk_pid);
1190 break;
1191 case -EPROTONOSUPPORT:
1192 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
1193 task->tk_pid);
1194 task->tk_status = 0;
1195 task->tk_action = call_bind;
1196 return;
1197 case -ECONNREFUSED: /* connection problems */
1198 case -ECONNRESET:
1199 case -ENOTCONN:
1200 case -EHOSTDOWN:
1201 case -EHOSTUNREACH:
1202 case -ENETUNREACH:
1203 case -EPIPE:
1204 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
1205 task->tk_pid, task->tk_status);
1206 if (!RPC_IS_SOFTCONN(task)) {
1207 rpc_delay(task, 5*HZ);
1208 goto retry_timeout;
1209 }
1210 status = task->tk_status;
1211 break;
1212 default:
1213 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
1214 task->tk_pid, -task->tk_status);
1215 }
1216
1217 rpc_exit(task, status);
1218 return;
1219
1220retry_timeout:
1221 task->tk_action = call_timeout;
1222}
1223
1224/*
1225 * 4b. Connect to the RPC server
1226 */
1227static void
1228call_connect(struct rpc_task *task)
1229{
1230 struct rpc_xprt *xprt = task->tk_xprt;
1231
1232 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
1233 task->tk_pid, xprt,
1234 (xprt_connected(xprt) ? "is" : "is not"));
1235
1236 task->tk_action = call_transmit;
1237 if (!xprt_connected(xprt)) {
1238 task->tk_action = call_connect_status;
1239 if (task->tk_status < 0)
1240 return;
1241 xprt_connect(task);
1242 }
1243}
1244
1245/*
1246 * 4c. Sort out connect result
1247 */
1248static void
1249call_connect_status(struct rpc_task *task)
1250{
1251 struct rpc_clnt *clnt = task->tk_client;
1252 int status = task->tk_status;
1253
1254 dprint_status(task);
1255
1256 task->tk_status = 0;
1257 if (status >= 0 || status == -EAGAIN) {
1258 clnt->cl_stats->netreconn++;
1259 task->tk_action = call_transmit;
1260 return;
1261 }
1262
1263 switch (status) {
1264 /* if soft mounted, test if we've timed out */
1265 case -ETIMEDOUT:
1266 task->tk_action = call_timeout;
1267 break;
1268 default:
1269 rpc_exit(task, -EIO);
1270 }
1271}
1272
1273/*
1274 * 5. Transmit the RPC request, and wait for reply
1275 */
1276static void
1277call_transmit(struct rpc_task *task)
1278{
1279 dprint_status(task);
1280
1281 task->tk_action = call_status;
1282 if (task->tk_status < 0)
1283 return;
1284 task->tk_status = xprt_prepare_transmit(task);
1285 if (task->tk_status != 0)
1286 return;
1287 task->tk_action = call_transmit_status;
1288 /* Encode here so that rpcsec_gss can use correct sequence number. */
1289 if (rpc_task_need_encode(task)) {
1290 BUG_ON(task->tk_rqstp->rq_bytes_sent != 0);
1291 rpc_xdr_encode(task);
1292 /* Did the encode result in an error condition? */
1293 if (task->tk_status != 0) {
1294 /* Was the error nonfatal? */
1295 if (task->tk_status == -EAGAIN)
1296 rpc_delay(task, HZ >> 4);
1297 else
1298 rpc_exit(task, task->tk_status);
1299 return;
1300 }
1301 }
1302 xprt_transmit(task);
1303 if (task->tk_status < 0)
1304 return;
1305 /*
1306 * On success, ensure that we call xprt_end_transmit() before sleeping
1307 * in order to allow access to the socket to other RPC requests.
1308 */
1309 call_transmit_status(task);
1310 if (rpc_reply_expected(task))
1311 return;
1312 task->tk_action = rpc_exit_task;
1313 rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
1314}
1315
1316/*
1317 * 5a. Handle cleanup after a transmission
1318 */
1319static void
1320call_transmit_status(struct rpc_task *task)
1321{
1322 task->tk_action = call_status;
1323
1324 /*
1325 * Common case: success. Force the compiler to put this
1326 * test first.
1327 */
1328 if (task->tk_status == 0) {
1329 xprt_end_transmit(task);
1330 rpc_task_force_reencode(task);
1331 return;
1332 }
1333
1334 switch (task->tk_status) {
1335 case -EAGAIN:
1336 break;
1337 default:
1338 dprint_status(task);
1339 xprt_end_transmit(task);
1340 rpc_task_force_reencode(task);
1341 break;
1342 /*
1343 * Special cases: if we've been waiting on the
1344 * socket's write_space() callback, or if the
1345 * socket just returned a connection error,
1346 * then hold onto the transport lock.
1347 */
1348 case -ECONNREFUSED:
1349 case -EHOSTDOWN:
1350 case -EHOSTUNREACH:
1351 case -ENETUNREACH:
1352 if (RPC_IS_SOFTCONN(task)) {
1353 xprt_end_transmit(task);
1354 rpc_exit(task, task->tk_status);
1355 break;
1356 }
1357 case -ECONNRESET:
1358 case -ENOTCONN:
1359 case -EPIPE:
1360 rpc_task_force_reencode(task);
1361 }
1362}
1363
1364#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1365/*
1366 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
1367 * addition, disconnect on connectivity errors.
1368 */
1369static void
1370call_bc_transmit(struct rpc_task *task)
1371{
1372 struct rpc_rqst *req = task->tk_rqstp;
1373
1374 BUG_ON(task->tk_status != 0);
1375 task->tk_status = xprt_prepare_transmit(task);
1376 if (task->tk_status == -EAGAIN) {
1377 /*
1378 * Could not reserve the transport. Try again after the
1379 * transport is released.
1380 */
1381 task->tk_status = 0;
1382 task->tk_action = call_bc_transmit;
1383 return;
1384 }
1385
1386 task->tk_action = rpc_exit_task;
1387 if (task->tk_status < 0) {
1388 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1389 "error: %d\n", task->tk_status);
1390 return;
1391 }
1392
1393 xprt_transmit(task);
1394 xprt_end_transmit(task);
1395 dprint_status(task);
1396 switch (task->tk_status) {
1397 case 0:
1398 /* Success */
1399 break;
1400 case -EHOSTDOWN:
1401 case -EHOSTUNREACH:
1402 case -ENETUNREACH:
1403 case -ETIMEDOUT:
1404 /*
1405 * Problem reaching the server. Disconnect and let the
1406 * forechannel reestablish the connection. The server will
1407 * have to retransmit the backchannel request and we'll
1408 * reprocess it. Since these ops are idempotent, there's no
1409 * need to cache our reply at this time.
1410 */
1411 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1412 "error: %d\n", task->tk_status);
1413 xprt_conditional_disconnect(task->tk_xprt,
1414 req->rq_connect_cookie);
1415 break;
1416 default:
1417 /*
1418 * We were unable to reply and will have to drop the
1419 * request. The server should reconnect and retransmit.
1420 */
1421 BUG_ON(task->tk_status == -EAGAIN);
1422 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
1423 "error: %d\n", task->tk_status);
1424 break;
1425 }
1426 rpc_wake_up_queued_task(&req->rq_xprt->pending, task);
1427}
1428#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1429
1430/*
1431 * 6. Sort out the RPC call status
1432 */
1433static void
1434call_status(struct rpc_task *task)
1435{
1436 struct rpc_clnt *clnt = task->tk_client;
1437 struct rpc_rqst *req = task->tk_rqstp;
1438 int status;
1439
1440 if (req->rq_reply_bytes_recvd > 0 && !req->rq_bytes_sent)
1441 task->tk_status = req->rq_reply_bytes_recvd;
1442
1443 dprint_status(task);
1444
1445 status = task->tk_status;
1446 if (status >= 0) {
1447 task->tk_action = call_decode;
1448 return;
1449 }
1450
1451 task->tk_status = 0;
1452 switch(status) {
1453 case -EHOSTDOWN:
1454 case -EHOSTUNREACH:
1455 case -ENETUNREACH:
1456 /*
1457 * Delay any retries for 3 seconds, then handle as if it
1458 * were a timeout.
1459 */
1460 rpc_delay(task, 3*HZ);
1461 case -ETIMEDOUT:
1462 task->tk_action = call_timeout;
1463 if (task->tk_client->cl_discrtry)
1464 xprt_conditional_disconnect(task->tk_xprt,
1465 req->rq_connect_cookie);
1466 break;
1467 case -ECONNRESET:
1468 case -ECONNREFUSED:
1469 rpc_force_rebind(clnt);
1470 rpc_delay(task, 3*HZ);
1471 case -EPIPE:
1472 case -ENOTCONN:
1473 task->tk_action = call_bind;
1474 break;
1475 case -EAGAIN:
1476 task->tk_action = call_transmit;
1477 break;
1478 case -EIO:
1479 /* shutdown or soft timeout */
1480 rpc_exit(task, status);
1481 break;
1482 default:
1483 if (clnt->cl_chatty)
1484 printk("%s: RPC call returned error %d\n",
1485 clnt->cl_protname, -status);
1486 rpc_exit(task, status);
1487 }
1488}
1489
1490/*
1491 * 6a. Handle RPC timeout
1492 * We do not release the request slot, so we keep using the
1493 * same XID for all retransmits.
1494 */
1495static void
1496call_timeout(struct rpc_task *task)
1497{
1498 struct rpc_clnt *clnt = task->tk_client;
1499
1500 if (xprt_adjust_timeout(task->tk_rqstp) == 0) {
1501 dprintk("RPC: %5u call_timeout (minor)\n", task->tk_pid);
1502 goto retry;
1503 }
1504
1505 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
1506 task->tk_timeouts++;
1507
1508 if (RPC_IS_SOFTCONN(task)) {
1509 rpc_exit(task, -ETIMEDOUT);
1510 return;
1511 }
1512 if (RPC_IS_SOFT(task)) {
1513 if (clnt->cl_chatty)
1514 printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
1515 clnt->cl_protname, clnt->cl_server);
1516 if (task->tk_flags & RPC_TASK_TIMEOUT)
1517 rpc_exit(task, -ETIMEDOUT);
1518 else
1519 rpc_exit(task, -EIO);
1520 return;
1521 }
1522
1523 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
1524 task->tk_flags |= RPC_CALL_MAJORSEEN;
1525 if (clnt->cl_chatty)
1526 printk(KERN_NOTICE "%s: server %s not responding, still trying\n",
1527 clnt->cl_protname, clnt->cl_server);
1528 }
1529 rpc_force_rebind(clnt);
1530 /*
1531 * Did our request time out due to an RPCSEC_GSS out-of-sequence
1532 * event? RFC2203 requires the server to drop all such requests.
1533 */
1534 rpcauth_invalcred(task);
1535
1536retry:
1537 clnt->cl_stats->rpcretrans++;
1538 task->tk_action = call_bind;
1539 task->tk_status = 0;
1540}
1541
1542/*
1543 * 7. Decode the RPC reply
1544 */
1545static void
1546call_decode(struct rpc_task *task)
1547{
1548 struct rpc_clnt *clnt = task->tk_client;
1549 struct rpc_rqst *req = task->tk_rqstp;
1550 kxdrdproc_t decode = task->tk_msg.rpc_proc->p_decode;
1551 __be32 *p;
1552
1553 dprint_status(task);
1554
1555 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
1556 if (clnt->cl_chatty)
1557 printk(KERN_NOTICE "%s: server %s OK\n",
1558 clnt->cl_protname, clnt->cl_server);
1559 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
1560 }
1561
1562 /*
1563 * Ensure that we see all writes made by xprt_complete_rqst()
1564 * before it changed req->rq_reply_bytes_recvd.
1565 */
1566 smp_rmb();
1567 req->rq_rcv_buf.len = req->rq_private_buf.len;
1568
1569 /* Check that the softirq receive buffer is valid */
1570 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
1571 sizeof(req->rq_rcv_buf)) != 0);
1572
1573 if (req->rq_rcv_buf.len < 12) {
1574 if (!RPC_IS_SOFT(task)) {
1575 task->tk_action = call_bind;
1576 clnt->cl_stats->rpcretrans++;
1577 goto out_retry;
1578 }
1579 dprintk("RPC: %s: too small RPC reply size (%d bytes)\n",
1580 clnt->cl_protname, task->tk_status);
1581 task->tk_action = call_timeout;
1582 goto out_retry;
1583 }
1584
1585 p = rpc_verify_header(task);
1586 if (IS_ERR(p)) {
1587 if (p == ERR_PTR(-EAGAIN))
1588 goto out_retry;
1589 return;
1590 }
1591
1592 task->tk_action = rpc_exit_task;
1593
1594 if (decode) {
1595 task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
1596 task->tk_msg.rpc_resp);
1597 }
1598 dprintk("RPC: %5u call_decode result %d\n", task->tk_pid,
1599 task->tk_status);
1600 return;
1601out_retry:
1602 task->tk_status = 0;
1603 /* Note: rpc_verify_header() may have freed the RPC slot */
1604 if (task->tk_rqstp == req) {
1605 req->rq_reply_bytes_recvd = req->rq_rcv_buf.len = 0;
1606 if (task->tk_client->cl_discrtry)
1607 xprt_conditional_disconnect(task->tk_xprt,
1608 req->rq_connect_cookie);
1609 }
1610}
1611
1612static __be32 *
1613rpc_encode_header(struct rpc_task *task)
1614{
1615 struct rpc_clnt *clnt = task->tk_client;
1616 struct rpc_rqst *req = task->tk_rqstp;
1617 __be32 *p = req->rq_svec[0].iov_base;
1618
1619 /* FIXME: check buffer size? */
1620
1621 p = xprt_skip_transport_header(task->tk_xprt, p);
1622 *p++ = req->rq_xid; /* XID */
1623 *p++ = htonl(RPC_CALL); /* CALL */
1624 *p++ = htonl(RPC_VERSION); /* RPC version */
1625 *p++ = htonl(clnt->cl_prog); /* program number */
1626 *p++ = htonl(clnt->cl_vers); /* program version */
1627 *p++ = htonl(task->tk_msg.rpc_proc->p_proc); /* procedure */
1628 p = rpcauth_marshcred(task, p);
1629 req->rq_slen = xdr_adjust_iovec(&req->rq_svec[0], p);
1630 return p;
1631}
1632
1633static __be32 *
1634rpc_verify_header(struct rpc_task *task)
1635{
1636 struct kvec *iov = &task->tk_rqstp->rq_rcv_buf.head[0];
1637 int len = task->tk_rqstp->rq_rcv_buf.len >> 2;
1638 __be32 *p = iov->iov_base;
1639 u32 n;
1640 int error = -EACCES;
1641
1642 if ((task->tk_rqstp->rq_rcv_buf.len & 3) != 0) {
1643 /* RFC-1014 says that the representation of XDR data must be a
1644 * multiple of four bytes
1645 * - if it isn't pointer subtraction in the NFS client may give
1646 * undefined results
1647 */
1648 dprintk("RPC: %5u %s: XDR representation not a multiple of"
1649 " 4 bytes: 0x%x\n", task->tk_pid, __func__,
1650 task->tk_rqstp->rq_rcv_buf.len);
1651 goto out_eio;
1652 }
1653 if ((len -= 3) < 0)
1654 goto out_overflow;
1655
1656 p += 1; /* skip XID */
1657 if ((n = ntohl(*p++)) != RPC_REPLY) {
1658 dprintk("RPC: %5u %s: not an RPC reply: %x\n",
1659 task->tk_pid, __func__, n);
1660 goto out_garbage;
1661 }
1662
1663 if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
1664 if (--len < 0)
1665 goto out_overflow;
1666 switch ((n = ntohl(*p++))) {
1667 case RPC_AUTH_ERROR:
1668 break;
1669 case RPC_MISMATCH:
1670 dprintk("RPC: %5u %s: RPC call version mismatch!\n",
1671 task->tk_pid, __func__);
1672 error = -EPROTONOSUPPORT;
1673 goto out_err;
1674 default:
1675 dprintk("RPC: %5u %s: RPC call rejected, "
1676 "unknown error: %x\n",
1677 task->tk_pid, __func__, n);
1678 goto out_eio;
1679 }
1680 if (--len < 0)
1681 goto out_overflow;
1682 switch ((n = ntohl(*p++))) {
1683 case RPC_AUTH_REJECTEDCRED:
1684 case RPC_AUTH_REJECTEDVERF:
1685 case RPCSEC_GSS_CREDPROBLEM:
1686 case RPCSEC_GSS_CTXPROBLEM:
1687 if (!task->tk_cred_retry)
1688 break;
1689 task->tk_cred_retry--;
1690 dprintk("RPC: %5u %s: retry stale creds\n",
1691 task->tk_pid, __func__);
1692 rpcauth_invalcred(task);
1693 /* Ensure we obtain a new XID! */
1694 xprt_release(task);
1695 task->tk_action = call_reserve;
1696 goto out_retry;
1697 case RPC_AUTH_BADCRED:
1698 case RPC_AUTH_BADVERF:
1699 /* possibly garbled cred/verf? */
1700 if (!task->tk_garb_retry)
1701 break;
1702 task->tk_garb_retry--;
1703 dprintk("RPC: %5u %s: retry garbled creds\n",
1704 task->tk_pid, __func__);
1705 task->tk_action = call_bind;
1706 goto out_retry;
1707 case RPC_AUTH_TOOWEAK:
1708 printk(KERN_NOTICE "RPC: server %s requires stronger "
1709 "authentication.\n", task->tk_client->cl_server);
1710 break;
1711 default:
1712 dprintk("RPC: %5u %s: unknown auth error: %x\n",
1713 task->tk_pid, __func__, n);
1714 error = -EIO;
1715 }
1716 dprintk("RPC: %5u %s: call rejected %d\n",
1717 task->tk_pid, __func__, n);
1718 goto out_err;
1719 }
1720 if (!(p = rpcauth_checkverf(task, p))) {
1721 dprintk("RPC: %5u %s: auth check failed\n",
1722 task->tk_pid, __func__);
1723 goto out_garbage; /* bad verifier, retry */
1724 }
1725 len = p - (__be32 *)iov->iov_base - 1;
1726 if (len < 0)
1727 goto out_overflow;
1728 switch ((n = ntohl(*p++))) {
1729 case RPC_SUCCESS:
1730 return p;
1731 case RPC_PROG_UNAVAIL:
1732 dprintk("RPC: %5u %s: program %u is unsupported by server %s\n",
1733 task->tk_pid, __func__,
1734 (unsigned int)task->tk_client->cl_prog,
1735 task->tk_client->cl_server);
1736 error = -EPFNOSUPPORT;
1737 goto out_err;
1738 case RPC_PROG_MISMATCH:
1739 dprintk("RPC: %5u %s: program %u, version %u unsupported by "
1740 "server %s\n", task->tk_pid, __func__,
1741 (unsigned int)task->tk_client->cl_prog,
1742 (unsigned int)task->tk_client->cl_vers,
1743 task->tk_client->cl_server);
1744 error = -EPROTONOSUPPORT;
1745 goto out_err;
1746 case RPC_PROC_UNAVAIL:
1747 dprintk("RPC: %5u %s: proc %s unsupported by program %u, "
1748 "version %u on server %s\n",
1749 task->tk_pid, __func__,
1750 rpc_proc_name(task),
1751 task->tk_client->cl_prog,
1752 task->tk_client->cl_vers,
1753 task->tk_client->cl_server);
1754 error = -EOPNOTSUPP;
1755 goto out_err;
1756 case RPC_GARBAGE_ARGS:
1757 dprintk("RPC: %5u %s: server saw garbage\n",
1758 task->tk_pid, __func__);
1759 break; /* retry */
1760 default:
1761 dprintk("RPC: %5u %s: server accept status: %x\n",
1762 task->tk_pid, __func__, n);
1763 /* Also retry */
1764 }
1765
1766out_garbage:
1767 task->tk_client->cl_stats->rpcgarbage++;
1768 if (task->tk_garb_retry) {
1769 task->tk_garb_retry--;
1770 dprintk("RPC: %5u %s: retrying\n",
1771 task->tk_pid, __func__);
1772 task->tk_action = call_bind;
1773out_retry:
1774 return ERR_PTR(-EAGAIN);
1775 }
1776out_eio:
1777 error = -EIO;
1778out_err:
1779 rpc_exit(task, error);
1780 dprintk("RPC: %5u %s: call failed with error %d\n", task->tk_pid,
1781 __func__, error);
1782 return ERR_PTR(error);
1783out_overflow:
1784 dprintk("RPC: %5u %s: server reply was truncated.\n", task->tk_pid,
1785 __func__);
1786 goto out_garbage;
1787}
1788
1789static void rpcproc_encode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
1790{
1791}
1792
1793static int rpcproc_decode_null(void *rqstp, struct xdr_stream *xdr, void *obj)
1794{
1795 return 0;
1796}
1797
1798static struct rpc_procinfo rpcproc_null = {
1799 .p_encode = rpcproc_encode_null,
1800 .p_decode = rpcproc_decode_null,
1801};
1802
1803static int rpc_ping(struct rpc_clnt *clnt)
1804{
1805 struct rpc_message msg = {
1806 .rpc_proc = &rpcproc_null,
1807 };
1808 int err;
1809 msg.rpc_cred = authnull_ops.lookup_cred(NULL, NULL, 0);
1810 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN);
1811 put_rpccred(msg.rpc_cred);
1812 return err;
1813}
1814
1815struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
1816{
1817 struct rpc_message msg = {
1818 .rpc_proc = &rpcproc_null,
1819 .rpc_cred = cred,
1820 };
1821 struct rpc_task_setup task_setup_data = {
1822 .rpc_client = clnt,
1823 .rpc_message = &msg,
1824 .callback_ops = &rpc_default_ops,
1825 .flags = flags,
1826 };
1827 return rpc_run_task(&task_setup_data);
1828}
1829EXPORT_SYMBOL_GPL(rpc_call_null);
1830
1831#ifdef RPC_DEBUG
1832static void rpc_show_header(void)
1833{
1834 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
1835 "-timeout ---ops--\n");
1836}
1837
1838static void rpc_show_task(const struct rpc_clnt *clnt,
1839 const struct rpc_task *task)
1840{
1841 const char *rpc_waitq = "none";
1842
1843 if (RPC_IS_QUEUED(task))
1844 rpc_waitq = rpc_qname(task->tk_waitqueue);
1845
1846 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
1847 task->tk_pid, task->tk_flags, task->tk_status,
1848 clnt, task->tk_rqstp, task->tk_timeout, task->tk_ops,
1849 clnt->cl_protname, clnt->cl_vers, rpc_proc_name(task),
1850 task->tk_action, rpc_waitq);
1851}
1852
1853void rpc_show_tasks(void)
1854{
1855 struct rpc_clnt *clnt;
1856 struct rpc_task *task;
1857 int header = 0;
1858
1859 spin_lock(&rpc_client_lock);
1860 list_for_each_entry(clnt, &all_clients, cl_clients) {
1861 spin_lock(&clnt->cl_lock);
1862 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
1863 if (!header) {
1864 rpc_show_header();
1865 header++;
1866 }
1867 rpc_show_task(clnt, task);
1868 }
1869 spin_unlock(&clnt->cl_lock);
1870 }
1871 spin_unlock(&rpc_client_lock);
1872}
1873#endif