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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.h>
29#include <linux/rcupdate.h>
30#include <linux/utsname.h>
31#include <linux/workqueue.h>
32#include <linux/in.h>
33#include <linux/in6.h>
34#include <linux/un.h>
35
36#include <linux/sunrpc/clnt.h>
37#include <linux/sunrpc/addr.h>
38#include <linux/sunrpc/rpc_pipe_fs.h>
39#include <linux/sunrpc/metrics.h>
40#include <linux/sunrpc/bc_xprt.h>
41#include <trace/events/sunrpc.h>
42
43#include "sunrpc.h"
44#include "netns.h"
45
46#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
47# define RPCDBG_FACILITY RPCDBG_CALL
48#endif
49
50#define dprint_status(t) \
51 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
52 __func__, t->tk_status)
53
54/*
55 * All RPC clients are linked into this list
56 */
57
58static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
59
60
61static void call_start(struct rpc_task *task);
62static void call_reserve(struct rpc_task *task);
63static void call_reserveresult(struct rpc_task *task);
64static void call_allocate(struct rpc_task *task);
65static void call_encode(struct rpc_task *task);
66static void call_decode(struct rpc_task *task);
67static void call_bind(struct rpc_task *task);
68static void call_bind_status(struct rpc_task *task);
69static void call_transmit(struct rpc_task *task);
70static void call_status(struct rpc_task *task);
71static void call_transmit_status(struct rpc_task *task);
72static void call_refresh(struct rpc_task *task);
73static void call_refreshresult(struct rpc_task *task);
74static void call_connect(struct rpc_task *task);
75static void call_connect_status(struct rpc_task *task);
76
77static int rpc_encode_header(struct rpc_task *task,
78 struct xdr_stream *xdr);
79static int rpc_decode_header(struct rpc_task *task,
80 struct xdr_stream *xdr);
81static int rpc_ping(struct rpc_clnt *clnt);
82static void rpc_check_timeout(struct rpc_task *task);
83
84static void rpc_register_client(struct rpc_clnt *clnt)
85{
86 struct net *net = rpc_net_ns(clnt);
87 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
88
89 spin_lock(&sn->rpc_client_lock);
90 list_add(&clnt->cl_clients, &sn->all_clients);
91 spin_unlock(&sn->rpc_client_lock);
92}
93
94static void rpc_unregister_client(struct rpc_clnt *clnt)
95{
96 struct net *net = rpc_net_ns(clnt);
97 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
98
99 spin_lock(&sn->rpc_client_lock);
100 list_del(&clnt->cl_clients);
101 spin_unlock(&sn->rpc_client_lock);
102}
103
104static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
105{
106 rpc_remove_client_dir(clnt);
107}
108
109static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
110{
111 struct net *net = rpc_net_ns(clnt);
112 struct super_block *pipefs_sb;
113
114 pipefs_sb = rpc_get_sb_net(net);
115 if (pipefs_sb) {
116 __rpc_clnt_remove_pipedir(clnt);
117 rpc_put_sb_net(net);
118 }
119}
120
121static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
122 struct rpc_clnt *clnt)
123{
124 static uint32_t clntid;
125 const char *dir_name = clnt->cl_program->pipe_dir_name;
126 char name[15];
127 struct dentry *dir, *dentry;
128
129 dir = rpc_d_lookup_sb(sb, dir_name);
130 if (dir == NULL) {
131 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
132 return dir;
133 }
134 for (;;) {
135 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
136 name[sizeof(name) - 1] = '\0';
137 dentry = rpc_create_client_dir(dir, name, clnt);
138 if (!IS_ERR(dentry))
139 break;
140 if (dentry == ERR_PTR(-EEXIST))
141 continue;
142 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
143 " %s/%s, error %ld\n",
144 dir_name, name, PTR_ERR(dentry));
145 break;
146 }
147 dput(dir);
148 return dentry;
149}
150
151static int
152rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
153{
154 struct dentry *dentry;
155
156 if (clnt->cl_program->pipe_dir_name != NULL) {
157 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
158 if (IS_ERR(dentry))
159 return PTR_ERR(dentry);
160 }
161 return 0;
162}
163
164static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
165{
166 if (clnt->cl_program->pipe_dir_name == NULL)
167 return 1;
168
169 switch (event) {
170 case RPC_PIPEFS_MOUNT:
171 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
172 return 1;
173 if (atomic_read(&clnt->cl_count) == 0)
174 return 1;
175 break;
176 case RPC_PIPEFS_UMOUNT:
177 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
178 return 1;
179 break;
180 }
181 return 0;
182}
183
184static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
185 struct super_block *sb)
186{
187 struct dentry *dentry;
188
189 switch (event) {
190 case RPC_PIPEFS_MOUNT:
191 dentry = rpc_setup_pipedir_sb(sb, clnt);
192 if (!dentry)
193 return -ENOENT;
194 if (IS_ERR(dentry))
195 return PTR_ERR(dentry);
196 break;
197 case RPC_PIPEFS_UMOUNT:
198 __rpc_clnt_remove_pipedir(clnt);
199 break;
200 default:
201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
202 return -ENOTSUPP;
203 }
204 return 0;
205}
206
207static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
208 struct super_block *sb)
209{
210 int error = 0;
211
212 for (;; clnt = clnt->cl_parent) {
213 if (!rpc_clnt_skip_event(clnt, event))
214 error = __rpc_clnt_handle_event(clnt, event, sb);
215 if (error || clnt == clnt->cl_parent)
216 break;
217 }
218 return error;
219}
220
221static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
222{
223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
224 struct rpc_clnt *clnt;
225
226 spin_lock(&sn->rpc_client_lock);
227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
228 if (rpc_clnt_skip_event(clnt, event))
229 continue;
230 spin_unlock(&sn->rpc_client_lock);
231 return clnt;
232 }
233 spin_unlock(&sn->rpc_client_lock);
234 return NULL;
235}
236
237static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
238 void *ptr)
239{
240 struct super_block *sb = ptr;
241 struct rpc_clnt *clnt;
242 int error = 0;
243
244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
245 error = __rpc_pipefs_event(clnt, event, sb);
246 if (error)
247 break;
248 }
249 return error;
250}
251
252static struct notifier_block rpc_clients_block = {
253 .notifier_call = rpc_pipefs_event,
254 .priority = SUNRPC_PIPEFS_RPC_PRIO,
255};
256
257int rpc_clients_notifier_register(void)
258{
259 return rpc_pipefs_notifier_register(&rpc_clients_block);
260}
261
262void rpc_clients_notifier_unregister(void)
263{
264 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
265}
266
267static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
268 struct rpc_xprt *xprt,
269 const struct rpc_timeout *timeout)
270{
271 struct rpc_xprt *old;
272
273 spin_lock(&clnt->cl_lock);
274 old = rcu_dereference_protected(clnt->cl_xprt,
275 lockdep_is_held(&clnt->cl_lock));
276
277 if (!xprt_bound(xprt))
278 clnt->cl_autobind = 1;
279
280 clnt->cl_timeout = timeout;
281 rcu_assign_pointer(clnt->cl_xprt, xprt);
282 spin_unlock(&clnt->cl_lock);
283
284 return old;
285}
286
287static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
288{
289 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
290 nodename, sizeof(clnt->cl_nodename));
291}
292
293static int rpc_client_register(struct rpc_clnt *clnt,
294 rpc_authflavor_t pseudoflavor,
295 const char *client_name)
296{
297 struct rpc_auth_create_args auth_args = {
298 .pseudoflavor = pseudoflavor,
299 .target_name = client_name,
300 };
301 struct rpc_auth *auth;
302 struct net *net = rpc_net_ns(clnt);
303 struct super_block *pipefs_sb;
304 int err;
305
306 rpc_clnt_debugfs_register(clnt);
307
308 pipefs_sb = rpc_get_sb_net(net);
309 if (pipefs_sb) {
310 err = rpc_setup_pipedir(pipefs_sb, clnt);
311 if (err)
312 goto out;
313 }
314
315 rpc_register_client(clnt);
316 if (pipefs_sb)
317 rpc_put_sb_net(net);
318
319 auth = rpcauth_create(&auth_args, clnt);
320 if (IS_ERR(auth)) {
321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
322 pseudoflavor);
323 err = PTR_ERR(auth);
324 goto err_auth;
325 }
326 return 0;
327err_auth:
328 pipefs_sb = rpc_get_sb_net(net);
329 rpc_unregister_client(clnt);
330 __rpc_clnt_remove_pipedir(clnt);
331out:
332 if (pipefs_sb)
333 rpc_put_sb_net(net);
334 rpc_clnt_debugfs_unregister(clnt);
335 return err;
336}
337
338static DEFINE_IDA(rpc_clids);
339
340void rpc_cleanup_clids(void)
341{
342 ida_destroy(&rpc_clids);
343}
344
345static int rpc_alloc_clid(struct rpc_clnt *clnt)
346{
347 int clid;
348
349 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
350 if (clid < 0)
351 return clid;
352 clnt->cl_clid = clid;
353 return 0;
354}
355
356static void rpc_free_clid(struct rpc_clnt *clnt)
357{
358 ida_simple_remove(&rpc_clids, clnt->cl_clid);
359}
360
361static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
362 struct rpc_xprt_switch *xps,
363 struct rpc_xprt *xprt,
364 struct rpc_clnt *parent)
365{
366 const struct rpc_program *program = args->program;
367 const struct rpc_version *version;
368 struct rpc_clnt *clnt = NULL;
369 const struct rpc_timeout *timeout;
370 const char *nodename = args->nodename;
371 int err;
372
373 err = rpciod_up();
374 if (err)
375 goto out_no_rpciod;
376
377 err = -EINVAL;
378 if (args->version >= program->nrvers)
379 goto out_err;
380 version = program->version[args->version];
381 if (version == NULL)
382 goto out_err;
383
384 err = -ENOMEM;
385 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
386 if (!clnt)
387 goto out_err;
388 clnt->cl_parent = parent ? : clnt;
389
390 err = rpc_alloc_clid(clnt);
391 if (err)
392 goto out_no_clid;
393
394 clnt->cl_cred = get_cred(args->cred);
395 clnt->cl_procinfo = version->procs;
396 clnt->cl_maxproc = version->nrprocs;
397 clnt->cl_prog = args->prognumber ? : program->number;
398 clnt->cl_vers = version->number;
399 clnt->cl_stats = program->stats;
400 clnt->cl_metrics = rpc_alloc_iostats(clnt);
401 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
402 err = -ENOMEM;
403 if (clnt->cl_metrics == NULL)
404 goto out_no_stats;
405 clnt->cl_program = program;
406 INIT_LIST_HEAD(&clnt->cl_tasks);
407 spin_lock_init(&clnt->cl_lock);
408
409 timeout = xprt->timeout;
410 if (args->timeout != NULL) {
411 memcpy(&clnt->cl_timeout_default, args->timeout,
412 sizeof(clnt->cl_timeout_default));
413 timeout = &clnt->cl_timeout_default;
414 }
415
416 rpc_clnt_set_transport(clnt, xprt, timeout);
417 xprt_iter_init(&clnt->cl_xpi, xps);
418 xprt_switch_put(xps);
419
420 clnt->cl_rtt = &clnt->cl_rtt_default;
421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
422
423 atomic_set(&clnt->cl_count, 1);
424
425 if (nodename == NULL)
426 nodename = utsname()->nodename;
427 /* save the nodename */
428 rpc_clnt_set_nodename(clnt, nodename);
429
430 err = rpc_client_register(clnt, args->authflavor, args->client_name);
431 if (err)
432 goto out_no_path;
433 if (parent)
434 atomic_inc(&parent->cl_count);
435
436 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
437 return clnt;
438
439out_no_path:
440 rpc_free_iostats(clnt->cl_metrics);
441out_no_stats:
442 put_cred(clnt->cl_cred);
443 rpc_free_clid(clnt);
444out_no_clid:
445 kfree(clnt);
446out_err:
447 rpciod_down();
448out_no_rpciod:
449 xprt_switch_put(xps);
450 xprt_put(xprt);
451 trace_rpc_clnt_new_err(program->name, args->servername, err);
452 return ERR_PTR(err);
453}
454
455static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
456 struct rpc_xprt *xprt)
457{
458 struct rpc_clnt *clnt = NULL;
459 struct rpc_xprt_switch *xps;
460
461 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
462 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
463 xps = args->bc_xprt->xpt_bc_xps;
464 xprt_switch_get(xps);
465 } else {
466 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
467 if (xps == NULL) {
468 xprt_put(xprt);
469 return ERR_PTR(-ENOMEM);
470 }
471 if (xprt->bc_xprt) {
472 xprt_switch_get(xps);
473 xprt->bc_xprt->xpt_bc_xps = xps;
474 }
475 }
476 clnt = rpc_new_client(args, xps, xprt, NULL);
477 if (IS_ERR(clnt))
478 return clnt;
479
480 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
481 int err = rpc_ping(clnt);
482 if (err != 0) {
483 rpc_shutdown_client(clnt);
484 return ERR_PTR(err);
485 }
486 }
487
488 clnt->cl_softrtry = 1;
489 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
490 clnt->cl_softrtry = 0;
491 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
492 clnt->cl_softerr = 1;
493 }
494
495 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
496 clnt->cl_autobind = 1;
497 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
498 clnt->cl_noretranstimeo = 1;
499 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
500 clnt->cl_discrtry = 1;
501 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
502 clnt->cl_chatty = 1;
503
504 return clnt;
505}
506
507/**
508 * rpc_create - create an RPC client and transport with one call
509 * @args: rpc_clnt create argument structure
510 *
511 * Creates and initializes an RPC transport and an RPC client.
512 *
513 * It can ping the server in order to determine if it is up, and to see if
514 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
515 * this behavior so asynchronous tasks can also use rpc_create.
516 */
517struct rpc_clnt *rpc_create(struct rpc_create_args *args)
518{
519 struct rpc_xprt *xprt;
520 struct xprt_create xprtargs = {
521 .net = args->net,
522 .ident = args->protocol,
523 .srcaddr = args->saddress,
524 .dstaddr = args->address,
525 .addrlen = args->addrsize,
526 .servername = args->servername,
527 .bc_xprt = args->bc_xprt,
528 };
529 char servername[48];
530 struct rpc_clnt *clnt;
531 int i;
532
533 if (args->bc_xprt) {
534 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
535 xprt = args->bc_xprt->xpt_bc_xprt;
536 if (xprt) {
537 xprt_get(xprt);
538 return rpc_create_xprt(args, xprt);
539 }
540 }
541
542 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
543 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
544 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
545 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
546 /*
547 * If the caller chooses not to specify a hostname, whip
548 * up a string representation of the passed-in address.
549 */
550 if (xprtargs.servername == NULL) {
551 struct sockaddr_un *sun =
552 (struct sockaddr_un *)args->address;
553 struct sockaddr_in *sin =
554 (struct sockaddr_in *)args->address;
555 struct sockaddr_in6 *sin6 =
556 (struct sockaddr_in6 *)args->address;
557
558 servername[0] = '\0';
559 switch (args->address->sa_family) {
560 case AF_LOCAL:
561 snprintf(servername, sizeof(servername), "%s",
562 sun->sun_path);
563 break;
564 case AF_INET:
565 snprintf(servername, sizeof(servername), "%pI4",
566 &sin->sin_addr.s_addr);
567 break;
568 case AF_INET6:
569 snprintf(servername, sizeof(servername), "%pI6",
570 &sin6->sin6_addr);
571 break;
572 default:
573 /* caller wants default server name, but
574 * address family isn't recognized. */
575 return ERR_PTR(-EINVAL);
576 }
577 xprtargs.servername = servername;
578 }
579
580 xprt = xprt_create_transport(&xprtargs);
581 if (IS_ERR(xprt))
582 return (struct rpc_clnt *)xprt;
583
584 /*
585 * By default, kernel RPC client connects from a reserved port.
586 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
587 * but it is always enabled for rpciod, which handles the connect
588 * operation.
589 */
590 xprt->resvport = 1;
591 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
592 xprt->resvport = 0;
593 xprt->reuseport = 0;
594 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
595 xprt->reuseport = 1;
596
597 clnt = rpc_create_xprt(args, xprt);
598 if (IS_ERR(clnt) || args->nconnect <= 1)
599 return clnt;
600
601 for (i = 0; i < args->nconnect - 1; i++) {
602 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
603 break;
604 }
605 return clnt;
606}
607EXPORT_SYMBOL_GPL(rpc_create);
608
609/*
610 * This function clones the RPC client structure. It allows us to share the
611 * same transport while varying parameters such as the authentication
612 * flavour.
613 */
614static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
615 struct rpc_clnt *clnt)
616{
617 struct rpc_xprt_switch *xps;
618 struct rpc_xprt *xprt;
619 struct rpc_clnt *new;
620 int err;
621
622 err = -ENOMEM;
623 rcu_read_lock();
624 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
625 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
626 rcu_read_unlock();
627 if (xprt == NULL || xps == NULL) {
628 xprt_put(xprt);
629 xprt_switch_put(xps);
630 goto out_err;
631 }
632 args->servername = xprt->servername;
633 args->nodename = clnt->cl_nodename;
634
635 new = rpc_new_client(args, xps, xprt, clnt);
636 if (IS_ERR(new))
637 return new;
638
639 /* Turn off autobind on clones */
640 new->cl_autobind = 0;
641 new->cl_softrtry = clnt->cl_softrtry;
642 new->cl_softerr = clnt->cl_softerr;
643 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
644 new->cl_discrtry = clnt->cl_discrtry;
645 new->cl_chatty = clnt->cl_chatty;
646 new->cl_principal = clnt->cl_principal;
647 return new;
648
649out_err:
650 trace_rpc_clnt_clone_err(clnt, err);
651 return ERR_PTR(err);
652}
653
654/**
655 * rpc_clone_client - Clone an RPC client structure
656 *
657 * @clnt: RPC client whose parameters are copied
658 *
659 * Returns a fresh RPC client or an ERR_PTR.
660 */
661struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
662{
663 struct rpc_create_args args = {
664 .program = clnt->cl_program,
665 .prognumber = clnt->cl_prog,
666 .version = clnt->cl_vers,
667 .authflavor = clnt->cl_auth->au_flavor,
668 .cred = clnt->cl_cred,
669 };
670 return __rpc_clone_client(&args, clnt);
671}
672EXPORT_SYMBOL_GPL(rpc_clone_client);
673
674/**
675 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
676 *
677 * @clnt: RPC client whose parameters are copied
678 * @flavor: security flavor for new client
679 *
680 * Returns a fresh RPC client or an ERR_PTR.
681 */
682struct rpc_clnt *
683rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
684{
685 struct rpc_create_args args = {
686 .program = clnt->cl_program,
687 .prognumber = clnt->cl_prog,
688 .version = clnt->cl_vers,
689 .authflavor = flavor,
690 .cred = clnt->cl_cred,
691 };
692 return __rpc_clone_client(&args, clnt);
693}
694EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
695
696/**
697 * rpc_switch_client_transport: switch the RPC transport on the fly
698 * @clnt: pointer to a struct rpc_clnt
699 * @args: pointer to the new transport arguments
700 * @timeout: pointer to the new timeout parameters
701 *
702 * This function allows the caller to switch the RPC transport for the
703 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
704 * server, for instance. It assumes that the caller has ensured that
705 * there are no active RPC tasks by using some form of locking.
706 *
707 * Returns zero if "clnt" is now using the new xprt. Otherwise a
708 * negative errno is returned, and "clnt" continues to use the old
709 * xprt.
710 */
711int rpc_switch_client_transport(struct rpc_clnt *clnt,
712 struct xprt_create *args,
713 const struct rpc_timeout *timeout)
714{
715 const struct rpc_timeout *old_timeo;
716 rpc_authflavor_t pseudoflavor;
717 struct rpc_xprt_switch *xps, *oldxps;
718 struct rpc_xprt *xprt, *old;
719 struct rpc_clnt *parent;
720 int err;
721
722 xprt = xprt_create_transport(args);
723 if (IS_ERR(xprt))
724 return PTR_ERR(xprt);
725
726 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
727 if (xps == NULL) {
728 xprt_put(xprt);
729 return -ENOMEM;
730 }
731
732 pseudoflavor = clnt->cl_auth->au_flavor;
733
734 old_timeo = clnt->cl_timeout;
735 old = rpc_clnt_set_transport(clnt, xprt, timeout);
736 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
737
738 rpc_unregister_client(clnt);
739 __rpc_clnt_remove_pipedir(clnt);
740 rpc_clnt_debugfs_unregister(clnt);
741
742 /*
743 * A new transport was created. "clnt" therefore
744 * becomes the root of a new cl_parent tree. clnt's
745 * children, if it has any, still point to the old xprt.
746 */
747 parent = clnt->cl_parent;
748 clnt->cl_parent = clnt;
749
750 /*
751 * The old rpc_auth cache cannot be re-used. GSS
752 * contexts in particular are between a single
753 * client and server.
754 */
755 err = rpc_client_register(clnt, pseudoflavor, NULL);
756 if (err)
757 goto out_revert;
758
759 synchronize_rcu();
760 if (parent != clnt)
761 rpc_release_client(parent);
762 xprt_switch_put(oldxps);
763 xprt_put(old);
764 trace_rpc_clnt_replace_xprt(clnt);
765 return 0;
766
767out_revert:
768 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
769 rpc_clnt_set_transport(clnt, old, old_timeo);
770 clnt->cl_parent = parent;
771 rpc_client_register(clnt, pseudoflavor, NULL);
772 xprt_switch_put(xps);
773 xprt_put(xprt);
774 trace_rpc_clnt_replace_xprt_err(clnt);
775 return err;
776}
777EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
778
779static
780int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
781{
782 struct rpc_xprt_switch *xps;
783
784 rcu_read_lock();
785 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
786 rcu_read_unlock();
787 if (xps == NULL)
788 return -EAGAIN;
789 xprt_iter_init_listall(xpi, xps);
790 xprt_switch_put(xps);
791 return 0;
792}
793
794/**
795 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
796 * @clnt: pointer to client
797 * @fn: function to apply
798 * @data: void pointer to function data
799 *
800 * Iterates through the list of RPC transports currently attached to the
801 * client and applies the function fn(clnt, xprt, data).
802 *
803 * On error, the iteration stops, and the function returns the error value.
804 */
805int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
806 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
807 void *data)
808{
809 struct rpc_xprt_iter xpi;
810 int ret;
811
812 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
813 if (ret)
814 return ret;
815 for (;;) {
816 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
817
818 if (!xprt)
819 break;
820 ret = fn(clnt, xprt, data);
821 xprt_put(xprt);
822 if (ret < 0)
823 break;
824 }
825 xprt_iter_destroy(&xpi);
826 return ret;
827}
828EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
829
830/*
831 * Kill all tasks for the given client.
832 * XXX: kill their descendants as well?
833 */
834void rpc_killall_tasks(struct rpc_clnt *clnt)
835{
836 struct rpc_task *rovr;
837
838
839 if (list_empty(&clnt->cl_tasks))
840 return;
841
842 /*
843 * Spin lock all_tasks to prevent changes...
844 */
845 trace_rpc_clnt_killall(clnt);
846 spin_lock(&clnt->cl_lock);
847 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
848 rpc_signal_task(rovr);
849 spin_unlock(&clnt->cl_lock);
850}
851EXPORT_SYMBOL_GPL(rpc_killall_tasks);
852
853/*
854 * Properly shut down an RPC client, terminating all outstanding
855 * requests.
856 */
857void rpc_shutdown_client(struct rpc_clnt *clnt)
858{
859 might_sleep();
860
861 trace_rpc_clnt_shutdown(clnt);
862
863 while (!list_empty(&clnt->cl_tasks)) {
864 rpc_killall_tasks(clnt);
865 wait_event_timeout(destroy_wait,
866 list_empty(&clnt->cl_tasks), 1*HZ);
867 }
868
869 rpc_release_client(clnt);
870}
871EXPORT_SYMBOL_GPL(rpc_shutdown_client);
872
873/*
874 * Free an RPC client
875 */
876static void rpc_free_client_work(struct work_struct *work)
877{
878 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
879
880 trace_rpc_clnt_free(clnt);
881
882 /* These might block on processes that might allocate memory,
883 * so they cannot be called in rpciod, so they are handled separately
884 * here.
885 */
886 rpc_clnt_debugfs_unregister(clnt);
887 rpc_free_clid(clnt);
888 rpc_clnt_remove_pipedir(clnt);
889 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
890
891 kfree(clnt);
892 rpciod_down();
893}
894static struct rpc_clnt *
895rpc_free_client(struct rpc_clnt *clnt)
896{
897 struct rpc_clnt *parent = NULL;
898
899 trace_rpc_clnt_release(clnt);
900 if (clnt->cl_parent != clnt)
901 parent = clnt->cl_parent;
902 rpc_unregister_client(clnt);
903 rpc_free_iostats(clnt->cl_metrics);
904 clnt->cl_metrics = NULL;
905 xprt_iter_destroy(&clnt->cl_xpi);
906 put_cred(clnt->cl_cred);
907
908 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
909 schedule_work(&clnt->cl_work);
910 return parent;
911}
912
913/*
914 * Free an RPC client
915 */
916static struct rpc_clnt *
917rpc_free_auth(struct rpc_clnt *clnt)
918{
919 if (clnt->cl_auth == NULL)
920 return rpc_free_client(clnt);
921
922 /*
923 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
924 * release remaining GSS contexts. This mechanism ensures
925 * that it can do so safely.
926 */
927 atomic_inc(&clnt->cl_count);
928 rpcauth_release(clnt->cl_auth);
929 clnt->cl_auth = NULL;
930 if (atomic_dec_and_test(&clnt->cl_count))
931 return rpc_free_client(clnt);
932 return NULL;
933}
934
935/*
936 * Release reference to the RPC client
937 */
938void
939rpc_release_client(struct rpc_clnt *clnt)
940{
941 do {
942 if (list_empty(&clnt->cl_tasks))
943 wake_up(&destroy_wait);
944 if (!atomic_dec_and_test(&clnt->cl_count))
945 break;
946 clnt = rpc_free_auth(clnt);
947 } while (clnt != NULL);
948}
949EXPORT_SYMBOL_GPL(rpc_release_client);
950
951/**
952 * rpc_bind_new_program - bind a new RPC program to an existing client
953 * @old: old rpc_client
954 * @program: rpc program to set
955 * @vers: rpc program version
956 *
957 * Clones the rpc client and sets up a new RPC program. This is mainly
958 * of use for enabling different RPC programs to share the same transport.
959 * The Sun NFSv2/v3 ACL protocol can do this.
960 */
961struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
962 const struct rpc_program *program,
963 u32 vers)
964{
965 struct rpc_create_args args = {
966 .program = program,
967 .prognumber = program->number,
968 .version = vers,
969 .authflavor = old->cl_auth->au_flavor,
970 .cred = old->cl_cred,
971 };
972 struct rpc_clnt *clnt;
973 int err;
974
975 clnt = __rpc_clone_client(&args, old);
976 if (IS_ERR(clnt))
977 goto out;
978 err = rpc_ping(clnt);
979 if (err != 0) {
980 rpc_shutdown_client(clnt);
981 clnt = ERR_PTR(err);
982 }
983out:
984 return clnt;
985}
986EXPORT_SYMBOL_GPL(rpc_bind_new_program);
987
988struct rpc_xprt *
989rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
990{
991 struct rpc_xprt_switch *xps;
992
993 if (!xprt)
994 return NULL;
995 rcu_read_lock();
996 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
997 atomic_long_inc(&xps->xps_queuelen);
998 rcu_read_unlock();
999 atomic_long_inc(&xprt->queuelen);
1000
1001 return xprt;
1002}
1003
1004static void
1005rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1006{
1007 struct rpc_xprt_switch *xps;
1008
1009 atomic_long_dec(&xprt->queuelen);
1010 rcu_read_lock();
1011 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1012 atomic_long_dec(&xps->xps_queuelen);
1013 rcu_read_unlock();
1014
1015 xprt_put(xprt);
1016}
1017
1018void rpc_task_release_transport(struct rpc_task *task)
1019{
1020 struct rpc_xprt *xprt = task->tk_xprt;
1021
1022 if (xprt) {
1023 task->tk_xprt = NULL;
1024 if (task->tk_client)
1025 rpc_task_release_xprt(task->tk_client, xprt);
1026 else
1027 xprt_put(xprt);
1028 }
1029}
1030EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1031
1032void rpc_task_release_client(struct rpc_task *task)
1033{
1034 struct rpc_clnt *clnt = task->tk_client;
1035
1036 rpc_task_release_transport(task);
1037 if (clnt != NULL) {
1038 /* Remove from client task list */
1039 spin_lock(&clnt->cl_lock);
1040 list_del(&task->tk_task);
1041 spin_unlock(&clnt->cl_lock);
1042 task->tk_client = NULL;
1043
1044 rpc_release_client(clnt);
1045 }
1046}
1047
1048static struct rpc_xprt *
1049rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1050{
1051 struct rpc_xprt *xprt;
1052
1053 rcu_read_lock();
1054 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1055 rcu_read_unlock();
1056 return rpc_task_get_xprt(clnt, xprt);
1057}
1058
1059static struct rpc_xprt *
1060rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1061{
1062 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1063}
1064
1065static
1066void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1067{
1068 if (task->tk_xprt)
1069 return;
1070 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1071 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1072 else
1073 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1074}
1075
1076static
1077void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1078{
1079
1080 if (clnt != NULL) {
1081 rpc_task_set_transport(task, clnt);
1082 task->tk_client = clnt;
1083 atomic_inc(&clnt->cl_count);
1084 if (clnt->cl_softrtry)
1085 task->tk_flags |= RPC_TASK_SOFT;
1086 if (clnt->cl_softerr)
1087 task->tk_flags |= RPC_TASK_TIMEOUT;
1088 if (clnt->cl_noretranstimeo)
1089 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1090 if (atomic_read(&clnt->cl_swapper))
1091 task->tk_flags |= RPC_TASK_SWAPPER;
1092 /* Add to the client's list of all tasks */
1093 spin_lock(&clnt->cl_lock);
1094 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1095 spin_unlock(&clnt->cl_lock);
1096 }
1097}
1098
1099static void
1100rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1101{
1102 if (msg != NULL) {
1103 task->tk_msg.rpc_proc = msg->rpc_proc;
1104 task->tk_msg.rpc_argp = msg->rpc_argp;
1105 task->tk_msg.rpc_resp = msg->rpc_resp;
1106 task->tk_msg.rpc_cred = msg->rpc_cred;
1107 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1108 get_cred(task->tk_msg.rpc_cred);
1109 }
1110}
1111
1112/*
1113 * Default callback for async RPC calls
1114 */
1115static void
1116rpc_default_callback(struct rpc_task *task, void *data)
1117{
1118}
1119
1120static const struct rpc_call_ops rpc_default_ops = {
1121 .rpc_call_done = rpc_default_callback,
1122};
1123
1124/**
1125 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1126 * @task_setup_data: pointer to task initialisation data
1127 */
1128struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1129{
1130 struct rpc_task *task;
1131
1132 task = rpc_new_task(task_setup_data);
1133
1134 if (!RPC_IS_ASYNC(task))
1135 task->tk_flags |= RPC_TASK_CRED_NOREF;
1136
1137 rpc_task_set_client(task, task_setup_data->rpc_client);
1138 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1139
1140 if (task->tk_action == NULL)
1141 rpc_call_start(task);
1142
1143 atomic_inc(&task->tk_count);
1144 rpc_execute(task);
1145 return task;
1146}
1147EXPORT_SYMBOL_GPL(rpc_run_task);
1148
1149/**
1150 * rpc_call_sync - Perform a synchronous RPC call
1151 * @clnt: pointer to RPC client
1152 * @msg: RPC call parameters
1153 * @flags: RPC call flags
1154 */
1155int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1156{
1157 struct rpc_task *task;
1158 struct rpc_task_setup task_setup_data = {
1159 .rpc_client = clnt,
1160 .rpc_message = msg,
1161 .callback_ops = &rpc_default_ops,
1162 .flags = flags,
1163 };
1164 int status;
1165
1166 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1167 if (flags & RPC_TASK_ASYNC) {
1168 rpc_release_calldata(task_setup_data.callback_ops,
1169 task_setup_data.callback_data);
1170 return -EINVAL;
1171 }
1172
1173 task = rpc_run_task(&task_setup_data);
1174 if (IS_ERR(task))
1175 return PTR_ERR(task);
1176 status = task->tk_status;
1177 rpc_put_task(task);
1178 return status;
1179}
1180EXPORT_SYMBOL_GPL(rpc_call_sync);
1181
1182/**
1183 * rpc_call_async - Perform an asynchronous RPC call
1184 * @clnt: pointer to RPC client
1185 * @msg: RPC call parameters
1186 * @flags: RPC call flags
1187 * @tk_ops: RPC call ops
1188 * @data: user call data
1189 */
1190int
1191rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1192 const struct rpc_call_ops *tk_ops, void *data)
1193{
1194 struct rpc_task *task;
1195 struct rpc_task_setup task_setup_data = {
1196 .rpc_client = clnt,
1197 .rpc_message = msg,
1198 .callback_ops = tk_ops,
1199 .callback_data = data,
1200 .flags = flags|RPC_TASK_ASYNC,
1201 };
1202
1203 task = rpc_run_task(&task_setup_data);
1204 if (IS_ERR(task))
1205 return PTR_ERR(task);
1206 rpc_put_task(task);
1207 return 0;
1208}
1209EXPORT_SYMBOL_GPL(rpc_call_async);
1210
1211#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1212static void call_bc_encode(struct rpc_task *task);
1213
1214/**
1215 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1216 * rpc_execute against it
1217 * @req: RPC request
1218 */
1219struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1220{
1221 struct rpc_task *task;
1222 struct rpc_task_setup task_setup_data = {
1223 .callback_ops = &rpc_default_ops,
1224 .flags = RPC_TASK_SOFTCONN |
1225 RPC_TASK_NO_RETRANS_TIMEOUT,
1226 };
1227
1228 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1229 /*
1230 * Create an rpc_task to send the data
1231 */
1232 task = rpc_new_task(&task_setup_data);
1233 xprt_init_bc_request(req, task);
1234
1235 task->tk_action = call_bc_encode;
1236 atomic_inc(&task->tk_count);
1237 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1238 rpc_execute(task);
1239
1240 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1241 return task;
1242}
1243#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1244
1245/**
1246 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1247 * @req: RPC request to prepare
1248 * @pages: vector of struct page pointers
1249 * @base: offset in first page where receive should start, in bytes
1250 * @len: expected size of the upper layer data payload, in bytes
1251 * @hdrsize: expected size of upper layer reply header, in XDR words
1252 *
1253 */
1254void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1255 unsigned int base, unsigned int len,
1256 unsigned int hdrsize)
1257{
1258 /* Subtract one to force an extra word of buffer space for the
1259 * payload's XDR pad to fall into the rcv_buf's tail iovec.
1260 */
1261 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1;
1262
1263 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1264 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1265}
1266EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1267
1268void
1269rpc_call_start(struct rpc_task *task)
1270{
1271 task->tk_action = call_start;
1272}
1273EXPORT_SYMBOL_GPL(rpc_call_start);
1274
1275/**
1276 * rpc_peeraddr - extract remote peer address from clnt's xprt
1277 * @clnt: RPC client structure
1278 * @buf: target buffer
1279 * @bufsize: length of target buffer
1280 *
1281 * Returns the number of bytes that are actually in the stored address.
1282 */
1283size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1284{
1285 size_t bytes;
1286 struct rpc_xprt *xprt;
1287
1288 rcu_read_lock();
1289 xprt = rcu_dereference(clnt->cl_xprt);
1290
1291 bytes = xprt->addrlen;
1292 if (bytes > bufsize)
1293 bytes = bufsize;
1294 memcpy(buf, &xprt->addr, bytes);
1295 rcu_read_unlock();
1296
1297 return bytes;
1298}
1299EXPORT_SYMBOL_GPL(rpc_peeraddr);
1300
1301/**
1302 * rpc_peeraddr2str - return remote peer address in printable format
1303 * @clnt: RPC client structure
1304 * @format: address format
1305 *
1306 * NB: the lifetime of the memory referenced by the returned pointer is
1307 * the same as the rpc_xprt itself. As long as the caller uses this
1308 * pointer, it must hold the RCU read lock.
1309 */
1310const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1311 enum rpc_display_format_t format)
1312{
1313 struct rpc_xprt *xprt;
1314
1315 xprt = rcu_dereference(clnt->cl_xprt);
1316
1317 if (xprt->address_strings[format] != NULL)
1318 return xprt->address_strings[format];
1319 else
1320 return "unprintable";
1321}
1322EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1323
1324static const struct sockaddr_in rpc_inaddr_loopback = {
1325 .sin_family = AF_INET,
1326 .sin_addr.s_addr = htonl(INADDR_ANY),
1327};
1328
1329static const struct sockaddr_in6 rpc_in6addr_loopback = {
1330 .sin6_family = AF_INET6,
1331 .sin6_addr = IN6ADDR_ANY_INIT,
1332};
1333
1334/*
1335 * Try a getsockname() on a connected datagram socket. Using a
1336 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1337 * This conserves the ephemeral port number space.
1338 *
1339 * Returns zero and fills in "buf" if successful; otherwise, a
1340 * negative errno is returned.
1341 */
1342static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1343 struct sockaddr *buf)
1344{
1345 struct socket *sock;
1346 int err;
1347
1348 err = __sock_create(net, sap->sa_family,
1349 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1350 if (err < 0) {
1351 dprintk("RPC: can't create UDP socket (%d)\n", err);
1352 goto out;
1353 }
1354
1355 switch (sap->sa_family) {
1356 case AF_INET:
1357 err = kernel_bind(sock,
1358 (struct sockaddr *)&rpc_inaddr_loopback,
1359 sizeof(rpc_inaddr_loopback));
1360 break;
1361 case AF_INET6:
1362 err = kernel_bind(sock,
1363 (struct sockaddr *)&rpc_in6addr_loopback,
1364 sizeof(rpc_in6addr_loopback));
1365 break;
1366 default:
1367 err = -EAFNOSUPPORT;
1368 goto out;
1369 }
1370 if (err < 0) {
1371 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1372 goto out_release;
1373 }
1374
1375 err = kernel_connect(sock, sap, salen, 0);
1376 if (err < 0) {
1377 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1378 goto out_release;
1379 }
1380
1381 err = kernel_getsockname(sock, buf);
1382 if (err < 0) {
1383 dprintk("RPC: getsockname failed (%d)\n", err);
1384 goto out_release;
1385 }
1386
1387 err = 0;
1388 if (buf->sa_family == AF_INET6) {
1389 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1390 sin6->sin6_scope_id = 0;
1391 }
1392 dprintk("RPC: %s succeeded\n", __func__);
1393
1394out_release:
1395 sock_release(sock);
1396out:
1397 return err;
1398}
1399
1400/*
1401 * Scraping a connected socket failed, so we don't have a useable
1402 * local address. Fallback: generate an address that will prevent
1403 * the server from calling us back.
1404 *
1405 * Returns zero and fills in "buf" if successful; otherwise, a
1406 * negative errno is returned.
1407 */
1408static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1409{
1410 switch (family) {
1411 case AF_INET:
1412 if (buflen < sizeof(rpc_inaddr_loopback))
1413 return -EINVAL;
1414 memcpy(buf, &rpc_inaddr_loopback,
1415 sizeof(rpc_inaddr_loopback));
1416 break;
1417 case AF_INET6:
1418 if (buflen < sizeof(rpc_in6addr_loopback))
1419 return -EINVAL;
1420 memcpy(buf, &rpc_in6addr_loopback,
1421 sizeof(rpc_in6addr_loopback));
1422 break;
1423 default:
1424 dprintk("RPC: %s: address family not supported\n",
1425 __func__);
1426 return -EAFNOSUPPORT;
1427 }
1428 dprintk("RPC: %s: succeeded\n", __func__);
1429 return 0;
1430}
1431
1432/**
1433 * rpc_localaddr - discover local endpoint address for an RPC client
1434 * @clnt: RPC client structure
1435 * @buf: target buffer
1436 * @buflen: size of target buffer, in bytes
1437 *
1438 * Returns zero and fills in "buf" and "buflen" if successful;
1439 * otherwise, a negative errno is returned.
1440 *
1441 * This works even if the underlying transport is not currently connected,
1442 * or if the upper layer never previously provided a source address.
1443 *
1444 * The result of this function call is transient: multiple calls in
1445 * succession may give different results, depending on how local
1446 * networking configuration changes over time.
1447 */
1448int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1449{
1450 struct sockaddr_storage address;
1451 struct sockaddr *sap = (struct sockaddr *)&address;
1452 struct rpc_xprt *xprt;
1453 struct net *net;
1454 size_t salen;
1455 int err;
1456
1457 rcu_read_lock();
1458 xprt = rcu_dereference(clnt->cl_xprt);
1459 salen = xprt->addrlen;
1460 memcpy(sap, &xprt->addr, salen);
1461 net = get_net(xprt->xprt_net);
1462 rcu_read_unlock();
1463
1464 rpc_set_port(sap, 0);
1465 err = rpc_sockname(net, sap, salen, buf);
1466 put_net(net);
1467 if (err != 0)
1468 /* Couldn't discover local address, return ANYADDR */
1469 return rpc_anyaddr(sap->sa_family, buf, buflen);
1470 return 0;
1471}
1472EXPORT_SYMBOL_GPL(rpc_localaddr);
1473
1474void
1475rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1476{
1477 struct rpc_xprt *xprt;
1478
1479 rcu_read_lock();
1480 xprt = rcu_dereference(clnt->cl_xprt);
1481 if (xprt->ops->set_buffer_size)
1482 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1483 rcu_read_unlock();
1484}
1485EXPORT_SYMBOL_GPL(rpc_setbufsize);
1486
1487/**
1488 * rpc_net_ns - Get the network namespace for this RPC client
1489 * @clnt: RPC client to query
1490 *
1491 */
1492struct net *rpc_net_ns(struct rpc_clnt *clnt)
1493{
1494 struct net *ret;
1495
1496 rcu_read_lock();
1497 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1498 rcu_read_unlock();
1499 return ret;
1500}
1501EXPORT_SYMBOL_GPL(rpc_net_ns);
1502
1503/**
1504 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1505 * @clnt: RPC client to query
1506 *
1507 * For stream transports, this is one RPC record fragment (see RFC
1508 * 1831), as we don't support multi-record requests yet. For datagram
1509 * transports, this is the size of an IP packet minus the IP, UDP, and
1510 * RPC header sizes.
1511 */
1512size_t rpc_max_payload(struct rpc_clnt *clnt)
1513{
1514 size_t ret;
1515
1516 rcu_read_lock();
1517 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1518 rcu_read_unlock();
1519 return ret;
1520}
1521EXPORT_SYMBOL_GPL(rpc_max_payload);
1522
1523/**
1524 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1525 * @clnt: RPC client to query
1526 */
1527size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1528{
1529 struct rpc_xprt *xprt;
1530 size_t ret;
1531
1532 rcu_read_lock();
1533 xprt = rcu_dereference(clnt->cl_xprt);
1534 ret = xprt->ops->bc_maxpayload(xprt);
1535 rcu_read_unlock();
1536 return ret;
1537}
1538EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1539
1540unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1541{
1542 struct rpc_xprt *xprt;
1543 unsigned int ret;
1544
1545 rcu_read_lock();
1546 xprt = rcu_dereference(clnt->cl_xprt);
1547 ret = xprt->ops->bc_num_slots(xprt);
1548 rcu_read_unlock();
1549 return ret;
1550}
1551EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1552
1553/**
1554 * rpc_force_rebind - force transport to check that remote port is unchanged
1555 * @clnt: client to rebind
1556 *
1557 */
1558void rpc_force_rebind(struct rpc_clnt *clnt)
1559{
1560 if (clnt->cl_autobind) {
1561 rcu_read_lock();
1562 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1563 rcu_read_unlock();
1564 }
1565}
1566EXPORT_SYMBOL_GPL(rpc_force_rebind);
1567
1568static int
1569__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1570{
1571 task->tk_status = 0;
1572 task->tk_rpc_status = 0;
1573 task->tk_action = action;
1574 return 1;
1575}
1576
1577/*
1578 * Restart an (async) RPC call. Usually called from within the
1579 * exit handler.
1580 */
1581int
1582rpc_restart_call(struct rpc_task *task)
1583{
1584 return __rpc_restart_call(task, call_start);
1585}
1586EXPORT_SYMBOL_GPL(rpc_restart_call);
1587
1588/*
1589 * Restart an (async) RPC call from the call_prepare state.
1590 * Usually called from within the exit handler.
1591 */
1592int
1593rpc_restart_call_prepare(struct rpc_task *task)
1594{
1595 if (task->tk_ops->rpc_call_prepare != NULL)
1596 return __rpc_restart_call(task, rpc_prepare_task);
1597 return rpc_restart_call(task);
1598}
1599EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1600
1601const char
1602*rpc_proc_name(const struct rpc_task *task)
1603{
1604 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1605
1606 if (proc) {
1607 if (proc->p_name)
1608 return proc->p_name;
1609 else
1610 return "NULL";
1611 } else
1612 return "no proc";
1613}
1614
1615static void
1616__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1617{
1618 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1619 task->tk_rpc_status = rpc_status;
1620 rpc_exit(task, tk_status);
1621}
1622
1623static void
1624rpc_call_rpcerror(struct rpc_task *task, int status)
1625{
1626 __rpc_call_rpcerror(task, status, status);
1627}
1628
1629/*
1630 * 0. Initial state
1631 *
1632 * Other FSM states can be visited zero or more times, but
1633 * this state is visited exactly once for each RPC.
1634 */
1635static void
1636call_start(struct rpc_task *task)
1637{
1638 struct rpc_clnt *clnt = task->tk_client;
1639 int idx = task->tk_msg.rpc_proc->p_statidx;
1640
1641 trace_rpc_request(task);
1642 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1643 clnt->cl_program->name, clnt->cl_vers,
1644 rpc_proc_name(task),
1645 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1646
1647 /* Increment call count (version might not be valid for ping) */
1648 if (clnt->cl_program->version[clnt->cl_vers])
1649 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1650 clnt->cl_stats->rpccnt++;
1651 task->tk_action = call_reserve;
1652 rpc_task_set_transport(task, clnt);
1653}
1654
1655/*
1656 * 1. Reserve an RPC call slot
1657 */
1658static void
1659call_reserve(struct rpc_task *task)
1660{
1661 dprint_status(task);
1662
1663 task->tk_status = 0;
1664 task->tk_action = call_reserveresult;
1665 xprt_reserve(task);
1666}
1667
1668static void call_retry_reserve(struct rpc_task *task);
1669
1670/*
1671 * 1b. Grok the result of xprt_reserve()
1672 */
1673static void
1674call_reserveresult(struct rpc_task *task)
1675{
1676 int status = task->tk_status;
1677
1678 dprint_status(task);
1679
1680 /*
1681 * After a call to xprt_reserve(), we must have either
1682 * a request slot or else an error status.
1683 */
1684 task->tk_status = 0;
1685 if (status >= 0) {
1686 if (task->tk_rqstp) {
1687 task->tk_action = call_refresh;
1688 return;
1689 }
1690
1691 rpc_call_rpcerror(task, -EIO);
1692 return;
1693 }
1694
1695 /*
1696 * Even though there was an error, we may have acquired
1697 * a request slot somehow. Make sure not to leak it.
1698 */
1699 if (task->tk_rqstp)
1700 xprt_release(task);
1701
1702 switch (status) {
1703 case -ENOMEM:
1704 rpc_delay(task, HZ >> 2);
1705 fallthrough;
1706 case -EAGAIN: /* woken up; retry */
1707 task->tk_action = call_retry_reserve;
1708 return;
1709 default:
1710 rpc_call_rpcerror(task, status);
1711 }
1712}
1713
1714/*
1715 * 1c. Retry reserving an RPC call slot
1716 */
1717static void
1718call_retry_reserve(struct rpc_task *task)
1719{
1720 dprint_status(task);
1721
1722 task->tk_status = 0;
1723 task->tk_action = call_reserveresult;
1724 xprt_retry_reserve(task);
1725}
1726
1727/*
1728 * 2. Bind and/or refresh the credentials
1729 */
1730static void
1731call_refresh(struct rpc_task *task)
1732{
1733 dprint_status(task);
1734
1735 task->tk_action = call_refreshresult;
1736 task->tk_status = 0;
1737 task->tk_client->cl_stats->rpcauthrefresh++;
1738 rpcauth_refreshcred(task);
1739}
1740
1741/*
1742 * 2a. Process the results of a credential refresh
1743 */
1744static void
1745call_refreshresult(struct rpc_task *task)
1746{
1747 int status = task->tk_status;
1748
1749 dprint_status(task);
1750
1751 task->tk_status = 0;
1752 task->tk_action = call_refresh;
1753 switch (status) {
1754 case 0:
1755 if (rpcauth_uptodatecred(task)) {
1756 task->tk_action = call_allocate;
1757 return;
1758 }
1759 /* Use rate-limiting and a max number of retries if refresh
1760 * had status 0 but failed to update the cred.
1761 */
1762 fallthrough;
1763 case -ETIMEDOUT:
1764 rpc_delay(task, 3*HZ);
1765 fallthrough;
1766 case -EAGAIN:
1767 status = -EACCES;
1768 fallthrough;
1769 case -EKEYEXPIRED:
1770 if (!task->tk_cred_retry)
1771 break;
1772 task->tk_cred_retry--;
1773 dprintk("RPC: %5u %s: retry refresh creds\n",
1774 task->tk_pid, __func__);
1775 return;
1776 }
1777 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1778 task->tk_pid, __func__, status);
1779 rpc_call_rpcerror(task, status);
1780}
1781
1782/*
1783 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1784 * (Note: buffer memory is freed in xprt_release).
1785 */
1786static void
1787call_allocate(struct rpc_task *task)
1788{
1789 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1790 struct rpc_rqst *req = task->tk_rqstp;
1791 struct rpc_xprt *xprt = req->rq_xprt;
1792 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1793 int status;
1794
1795 dprint_status(task);
1796
1797 task->tk_status = 0;
1798 task->tk_action = call_encode;
1799
1800 if (req->rq_buffer)
1801 return;
1802
1803 if (proc->p_proc != 0) {
1804 BUG_ON(proc->p_arglen == 0);
1805 if (proc->p_decode != NULL)
1806 BUG_ON(proc->p_replen == 0);
1807 }
1808
1809 /*
1810 * Calculate the size (in quads) of the RPC call
1811 * and reply headers, and convert both values
1812 * to byte sizes.
1813 */
1814 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1815 proc->p_arglen;
1816 req->rq_callsize <<= 2;
1817 /*
1818 * Note: the reply buffer must at minimum allocate enough space
1819 * for the 'struct accepted_reply' from RFC5531.
1820 */
1821 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1822 max_t(size_t, proc->p_replen, 2);
1823 req->rq_rcvsize <<= 2;
1824
1825 status = xprt->ops->buf_alloc(task);
1826 xprt_inject_disconnect(xprt);
1827 if (status == 0)
1828 return;
1829 if (status != -ENOMEM) {
1830 rpc_call_rpcerror(task, status);
1831 return;
1832 }
1833
1834 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1835
1836 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1837 task->tk_action = call_allocate;
1838 rpc_delay(task, HZ>>4);
1839 return;
1840 }
1841
1842 rpc_call_rpcerror(task, -ERESTARTSYS);
1843}
1844
1845static int
1846rpc_task_need_encode(struct rpc_task *task)
1847{
1848 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1849 (!(task->tk_flags & RPC_TASK_SENT) ||
1850 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1851 xprt_request_need_retransmit(task));
1852}
1853
1854static void
1855rpc_xdr_encode(struct rpc_task *task)
1856{
1857 struct rpc_rqst *req = task->tk_rqstp;
1858 struct xdr_stream xdr;
1859
1860 xdr_buf_init(&req->rq_snd_buf,
1861 req->rq_buffer,
1862 req->rq_callsize);
1863 xdr_buf_init(&req->rq_rcv_buf,
1864 req->rq_rbuffer,
1865 req->rq_rcvsize);
1866
1867 req->rq_reply_bytes_recvd = 0;
1868 req->rq_snd_buf.head[0].iov_len = 0;
1869 xdr_init_encode(&xdr, &req->rq_snd_buf,
1870 req->rq_snd_buf.head[0].iov_base, req);
1871 xdr_free_bvec(&req->rq_snd_buf);
1872 if (rpc_encode_header(task, &xdr))
1873 return;
1874
1875 task->tk_status = rpcauth_wrap_req(task, &xdr);
1876}
1877
1878/*
1879 * 3. Encode arguments of an RPC call
1880 */
1881static void
1882call_encode(struct rpc_task *task)
1883{
1884 if (!rpc_task_need_encode(task))
1885 goto out;
1886 dprint_status(task);
1887 /* Dequeue task from the receive queue while we're encoding */
1888 xprt_request_dequeue_xprt(task);
1889 /* Encode here so that rpcsec_gss can use correct sequence number. */
1890 rpc_xdr_encode(task);
1891 /* Did the encode result in an error condition? */
1892 if (task->tk_status != 0) {
1893 /* Was the error nonfatal? */
1894 switch (task->tk_status) {
1895 case -EAGAIN:
1896 case -ENOMEM:
1897 rpc_delay(task, HZ >> 4);
1898 break;
1899 case -EKEYEXPIRED:
1900 if (!task->tk_cred_retry) {
1901 rpc_exit(task, task->tk_status);
1902 } else {
1903 task->tk_action = call_refresh;
1904 task->tk_cred_retry--;
1905 dprintk("RPC: %5u %s: retry refresh creds\n",
1906 task->tk_pid, __func__);
1907 }
1908 break;
1909 default:
1910 rpc_call_rpcerror(task, task->tk_status);
1911 }
1912 return;
1913 }
1914
1915 /* Add task to reply queue before transmission to avoid races */
1916 if (rpc_reply_expected(task))
1917 xprt_request_enqueue_receive(task);
1918 xprt_request_enqueue_transmit(task);
1919out:
1920 task->tk_action = call_transmit;
1921 /* Check that the connection is OK */
1922 if (!xprt_bound(task->tk_xprt))
1923 task->tk_action = call_bind;
1924 else if (!xprt_connected(task->tk_xprt))
1925 task->tk_action = call_connect;
1926}
1927
1928/*
1929 * Helpers to check if the task was already transmitted, and
1930 * to take action when that is the case.
1931 */
1932static bool
1933rpc_task_transmitted(struct rpc_task *task)
1934{
1935 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1936}
1937
1938static void
1939rpc_task_handle_transmitted(struct rpc_task *task)
1940{
1941 xprt_end_transmit(task);
1942 task->tk_action = call_transmit_status;
1943}
1944
1945/*
1946 * 4. Get the server port number if not yet set
1947 */
1948static void
1949call_bind(struct rpc_task *task)
1950{
1951 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1952
1953 if (rpc_task_transmitted(task)) {
1954 rpc_task_handle_transmitted(task);
1955 return;
1956 }
1957
1958 if (xprt_bound(xprt)) {
1959 task->tk_action = call_connect;
1960 return;
1961 }
1962
1963 dprint_status(task);
1964
1965 task->tk_action = call_bind_status;
1966 if (!xprt_prepare_transmit(task))
1967 return;
1968
1969 xprt->ops->rpcbind(task);
1970}
1971
1972/*
1973 * 4a. Sort out bind result
1974 */
1975static void
1976call_bind_status(struct rpc_task *task)
1977{
1978 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1979 int status = -EIO;
1980
1981 if (rpc_task_transmitted(task)) {
1982 rpc_task_handle_transmitted(task);
1983 return;
1984 }
1985
1986 dprint_status(task);
1987 trace_rpc_bind_status(task);
1988 if (task->tk_status >= 0)
1989 goto out_next;
1990 if (xprt_bound(xprt)) {
1991 task->tk_status = 0;
1992 goto out_next;
1993 }
1994
1995 switch (task->tk_status) {
1996 case -ENOMEM:
1997 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1998 rpc_delay(task, HZ >> 2);
1999 goto retry_timeout;
2000 case -EACCES:
2001 dprintk("RPC: %5u remote rpcbind: RPC program/version "
2002 "unavailable\n", task->tk_pid);
2003 /* fail immediately if this is an RPC ping */
2004 if (task->tk_msg.rpc_proc->p_proc == 0) {
2005 status = -EOPNOTSUPP;
2006 break;
2007 }
2008 if (task->tk_rebind_retry == 0)
2009 break;
2010 task->tk_rebind_retry--;
2011 rpc_delay(task, 3*HZ);
2012 goto retry_timeout;
2013 case -ENOBUFS:
2014 rpc_delay(task, HZ >> 2);
2015 goto retry_timeout;
2016 case -EAGAIN:
2017 goto retry_timeout;
2018 case -ETIMEDOUT:
2019 dprintk("RPC: %5u rpcbind request timed out\n",
2020 task->tk_pid);
2021 goto retry_timeout;
2022 case -EPFNOSUPPORT:
2023 /* server doesn't support any rpcbind version we know of */
2024 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
2025 task->tk_pid);
2026 break;
2027 case -EPROTONOSUPPORT:
2028 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
2029 task->tk_pid);
2030 goto retry_timeout;
2031 case -ECONNREFUSED: /* connection problems */
2032 case -ECONNRESET:
2033 case -ECONNABORTED:
2034 case -ENOTCONN:
2035 case -EHOSTDOWN:
2036 case -ENETDOWN:
2037 case -EHOSTUNREACH:
2038 case -ENETUNREACH:
2039 case -EPIPE:
2040 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
2041 task->tk_pid, task->tk_status);
2042 if (!RPC_IS_SOFTCONN(task)) {
2043 rpc_delay(task, 5*HZ);
2044 goto retry_timeout;
2045 }
2046 status = task->tk_status;
2047 break;
2048 default:
2049 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
2050 task->tk_pid, -task->tk_status);
2051 }
2052
2053 rpc_call_rpcerror(task, status);
2054 return;
2055out_next:
2056 task->tk_action = call_connect;
2057 return;
2058retry_timeout:
2059 task->tk_status = 0;
2060 task->tk_action = call_bind;
2061 rpc_check_timeout(task);
2062}
2063
2064/*
2065 * 4b. Connect to the RPC server
2066 */
2067static void
2068call_connect(struct rpc_task *task)
2069{
2070 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2071
2072 if (rpc_task_transmitted(task)) {
2073 rpc_task_handle_transmitted(task);
2074 return;
2075 }
2076
2077 if (xprt_connected(xprt)) {
2078 task->tk_action = call_transmit;
2079 return;
2080 }
2081
2082 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
2083 task->tk_pid, xprt,
2084 (xprt_connected(xprt) ? "is" : "is not"));
2085
2086 task->tk_action = call_connect_status;
2087 if (task->tk_status < 0)
2088 return;
2089 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2090 rpc_call_rpcerror(task, -ENOTCONN);
2091 return;
2092 }
2093 if (!xprt_prepare_transmit(task))
2094 return;
2095 xprt_connect(task);
2096}
2097
2098/*
2099 * 4c. Sort out connect result
2100 */
2101static void
2102call_connect_status(struct rpc_task *task)
2103{
2104 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2105 struct rpc_clnt *clnt = task->tk_client;
2106 int status = task->tk_status;
2107
2108 if (rpc_task_transmitted(task)) {
2109 rpc_task_handle_transmitted(task);
2110 return;
2111 }
2112
2113 dprint_status(task);
2114 trace_rpc_connect_status(task);
2115
2116 if (task->tk_status == 0) {
2117 clnt->cl_stats->netreconn++;
2118 goto out_next;
2119 }
2120 if (xprt_connected(xprt)) {
2121 task->tk_status = 0;
2122 goto out_next;
2123 }
2124
2125 task->tk_status = 0;
2126 switch (status) {
2127 case -ECONNREFUSED:
2128 /* A positive refusal suggests a rebind is needed. */
2129 if (RPC_IS_SOFTCONN(task))
2130 break;
2131 if (clnt->cl_autobind) {
2132 rpc_force_rebind(clnt);
2133 goto out_retry;
2134 }
2135 fallthrough;
2136 case -ECONNRESET:
2137 case -ECONNABORTED:
2138 case -ENETDOWN:
2139 case -ENETUNREACH:
2140 case -EHOSTUNREACH:
2141 case -EPIPE:
2142 case -EPROTO:
2143 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2144 task->tk_rqstp->rq_connect_cookie);
2145 if (RPC_IS_SOFTCONN(task))
2146 break;
2147 /* retry with existing socket, after a delay */
2148 rpc_delay(task, 3*HZ);
2149 fallthrough;
2150 case -EADDRINUSE:
2151 case -ENOTCONN:
2152 case -EAGAIN:
2153 case -ETIMEDOUT:
2154 goto out_retry;
2155 case -ENOBUFS:
2156 rpc_delay(task, HZ >> 2);
2157 goto out_retry;
2158 }
2159 rpc_call_rpcerror(task, status);
2160 return;
2161out_next:
2162 task->tk_action = call_transmit;
2163 return;
2164out_retry:
2165 /* Check for timeouts before looping back to call_bind */
2166 task->tk_action = call_bind;
2167 rpc_check_timeout(task);
2168}
2169
2170/*
2171 * 5. Transmit the RPC request, and wait for reply
2172 */
2173static void
2174call_transmit(struct rpc_task *task)
2175{
2176 if (rpc_task_transmitted(task)) {
2177 rpc_task_handle_transmitted(task);
2178 return;
2179 }
2180
2181 dprint_status(task);
2182
2183 task->tk_action = call_transmit_status;
2184 if (!xprt_prepare_transmit(task))
2185 return;
2186 task->tk_status = 0;
2187 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2188 if (!xprt_connected(task->tk_xprt)) {
2189 task->tk_status = -ENOTCONN;
2190 return;
2191 }
2192 xprt_transmit(task);
2193 }
2194 xprt_end_transmit(task);
2195}
2196
2197/*
2198 * 5a. Handle cleanup after a transmission
2199 */
2200static void
2201call_transmit_status(struct rpc_task *task)
2202{
2203 task->tk_action = call_status;
2204
2205 /*
2206 * Common case: success. Force the compiler to put this
2207 * test first.
2208 */
2209 if (rpc_task_transmitted(task)) {
2210 task->tk_status = 0;
2211 xprt_request_wait_receive(task);
2212 return;
2213 }
2214
2215 switch (task->tk_status) {
2216 default:
2217 dprint_status(task);
2218 break;
2219 case -EBADMSG:
2220 task->tk_status = 0;
2221 task->tk_action = call_encode;
2222 break;
2223 /*
2224 * Special cases: if we've been waiting on the
2225 * socket's write_space() callback, or if the
2226 * socket just returned a connection error,
2227 * then hold onto the transport lock.
2228 */
2229 case -ENOBUFS:
2230 rpc_delay(task, HZ>>2);
2231 fallthrough;
2232 case -EBADSLT:
2233 case -EAGAIN:
2234 task->tk_action = call_transmit;
2235 task->tk_status = 0;
2236 break;
2237 case -ECONNREFUSED:
2238 case -EHOSTDOWN:
2239 case -ENETDOWN:
2240 case -EHOSTUNREACH:
2241 case -ENETUNREACH:
2242 case -EPERM:
2243 if (RPC_IS_SOFTCONN(task)) {
2244 if (!task->tk_msg.rpc_proc->p_proc)
2245 trace_xprt_ping(task->tk_xprt,
2246 task->tk_status);
2247 rpc_call_rpcerror(task, task->tk_status);
2248 return;
2249 }
2250 fallthrough;
2251 case -ECONNRESET:
2252 case -ECONNABORTED:
2253 case -EADDRINUSE:
2254 case -ENOTCONN:
2255 case -EPIPE:
2256 task->tk_action = call_bind;
2257 task->tk_status = 0;
2258 break;
2259 }
2260 rpc_check_timeout(task);
2261}
2262
2263#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2264static void call_bc_transmit(struct rpc_task *task);
2265static void call_bc_transmit_status(struct rpc_task *task);
2266
2267static void
2268call_bc_encode(struct rpc_task *task)
2269{
2270 xprt_request_enqueue_transmit(task);
2271 task->tk_action = call_bc_transmit;
2272}
2273
2274/*
2275 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2276 * addition, disconnect on connectivity errors.
2277 */
2278static void
2279call_bc_transmit(struct rpc_task *task)
2280{
2281 task->tk_action = call_bc_transmit_status;
2282 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2283 if (!xprt_prepare_transmit(task))
2284 return;
2285 task->tk_status = 0;
2286 xprt_transmit(task);
2287 }
2288 xprt_end_transmit(task);
2289}
2290
2291static void
2292call_bc_transmit_status(struct rpc_task *task)
2293{
2294 struct rpc_rqst *req = task->tk_rqstp;
2295
2296 if (rpc_task_transmitted(task))
2297 task->tk_status = 0;
2298
2299 dprint_status(task);
2300
2301 switch (task->tk_status) {
2302 case 0:
2303 /* Success */
2304 case -ENETDOWN:
2305 case -EHOSTDOWN:
2306 case -EHOSTUNREACH:
2307 case -ENETUNREACH:
2308 case -ECONNRESET:
2309 case -ECONNREFUSED:
2310 case -EADDRINUSE:
2311 case -ENOTCONN:
2312 case -EPIPE:
2313 break;
2314 case -ENOBUFS:
2315 rpc_delay(task, HZ>>2);
2316 fallthrough;
2317 case -EBADSLT:
2318 case -EAGAIN:
2319 task->tk_status = 0;
2320 task->tk_action = call_bc_transmit;
2321 return;
2322 case -ETIMEDOUT:
2323 /*
2324 * Problem reaching the server. Disconnect and let the
2325 * forechannel reestablish the connection. The server will
2326 * have to retransmit the backchannel request and we'll
2327 * reprocess it. Since these ops are idempotent, there's no
2328 * need to cache our reply at this time.
2329 */
2330 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2331 "error: %d\n", task->tk_status);
2332 xprt_conditional_disconnect(req->rq_xprt,
2333 req->rq_connect_cookie);
2334 break;
2335 default:
2336 /*
2337 * We were unable to reply and will have to drop the
2338 * request. The server should reconnect and retransmit.
2339 */
2340 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2341 "error: %d\n", task->tk_status);
2342 break;
2343 }
2344 task->tk_action = rpc_exit_task;
2345}
2346#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2347
2348/*
2349 * 6. Sort out the RPC call status
2350 */
2351static void
2352call_status(struct rpc_task *task)
2353{
2354 struct rpc_clnt *clnt = task->tk_client;
2355 int status;
2356
2357 if (!task->tk_msg.rpc_proc->p_proc)
2358 trace_xprt_ping(task->tk_xprt, task->tk_status);
2359
2360 dprint_status(task);
2361
2362 status = task->tk_status;
2363 if (status >= 0) {
2364 task->tk_action = call_decode;
2365 return;
2366 }
2367
2368 trace_rpc_call_status(task);
2369 task->tk_status = 0;
2370 switch(status) {
2371 case -EHOSTDOWN:
2372 case -ENETDOWN:
2373 case -EHOSTUNREACH:
2374 case -ENETUNREACH:
2375 case -EPERM:
2376 if (RPC_IS_SOFTCONN(task))
2377 goto out_exit;
2378 /*
2379 * Delay any retries for 3 seconds, then handle as if it
2380 * were a timeout.
2381 */
2382 rpc_delay(task, 3*HZ);
2383 fallthrough;
2384 case -ETIMEDOUT:
2385 break;
2386 case -ECONNREFUSED:
2387 case -ECONNRESET:
2388 case -ECONNABORTED:
2389 case -ENOTCONN:
2390 rpc_force_rebind(clnt);
2391 break;
2392 case -EADDRINUSE:
2393 rpc_delay(task, 3*HZ);
2394 fallthrough;
2395 case -EPIPE:
2396 case -EAGAIN:
2397 break;
2398 case -EIO:
2399 /* shutdown or soft timeout */
2400 goto out_exit;
2401 default:
2402 if (clnt->cl_chatty)
2403 printk("%s: RPC call returned error %d\n",
2404 clnt->cl_program->name, -status);
2405 goto out_exit;
2406 }
2407 task->tk_action = call_encode;
2408 rpc_check_timeout(task);
2409 return;
2410out_exit:
2411 rpc_call_rpcerror(task, status);
2412}
2413
2414static bool
2415rpc_check_connected(const struct rpc_rqst *req)
2416{
2417 /* No allocated request or transport? return true */
2418 if (!req || !req->rq_xprt)
2419 return true;
2420 return xprt_connected(req->rq_xprt);
2421}
2422
2423static void
2424rpc_check_timeout(struct rpc_task *task)
2425{
2426 struct rpc_clnt *clnt = task->tk_client;
2427
2428 if (RPC_SIGNALLED(task)) {
2429 rpc_call_rpcerror(task, -ERESTARTSYS);
2430 return;
2431 }
2432
2433 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2434 return;
2435
2436 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2437 task->tk_timeouts++;
2438
2439 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2440 rpc_call_rpcerror(task, -ETIMEDOUT);
2441 return;
2442 }
2443
2444 if (RPC_IS_SOFT(task)) {
2445 /*
2446 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2447 * been sent, it should time out only if the transport
2448 * connection gets terminally broken.
2449 */
2450 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2451 rpc_check_connected(task->tk_rqstp))
2452 return;
2453
2454 if (clnt->cl_chatty) {
2455 pr_notice_ratelimited(
2456 "%s: server %s not responding, timed out\n",
2457 clnt->cl_program->name,
2458 task->tk_xprt->servername);
2459 }
2460 if (task->tk_flags & RPC_TASK_TIMEOUT)
2461 rpc_call_rpcerror(task, -ETIMEDOUT);
2462 else
2463 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2464 return;
2465 }
2466
2467 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2468 task->tk_flags |= RPC_CALL_MAJORSEEN;
2469 if (clnt->cl_chatty) {
2470 pr_notice_ratelimited(
2471 "%s: server %s not responding, still trying\n",
2472 clnt->cl_program->name,
2473 task->tk_xprt->servername);
2474 }
2475 }
2476 rpc_force_rebind(clnt);
2477 /*
2478 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2479 * event? RFC2203 requires the server to drop all such requests.
2480 */
2481 rpcauth_invalcred(task);
2482}
2483
2484/*
2485 * 7. Decode the RPC reply
2486 */
2487static void
2488call_decode(struct rpc_task *task)
2489{
2490 struct rpc_clnt *clnt = task->tk_client;
2491 struct rpc_rqst *req = task->tk_rqstp;
2492 struct xdr_stream xdr;
2493 int err;
2494
2495 dprint_status(task);
2496
2497 if (!task->tk_msg.rpc_proc->p_decode) {
2498 task->tk_action = rpc_exit_task;
2499 return;
2500 }
2501
2502 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2503 if (clnt->cl_chatty) {
2504 pr_notice_ratelimited("%s: server %s OK\n",
2505 clnt->cl_program->name,
2506 task->tk_xprt->servername);
2507 }
2508 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2509 }
2510
2511 /*
2512 * Ensure that we see all writes made by xprt_complete_rqst()
2513 * before it changed req->rq_reply_bytes_recvd.
2514 */
2515 smp_rmb();
2516
2517 /*
2518 * Did we ever call xprt_complete_rqst()? If not, we should assume
2519 * the message is incomplete.
2520 */
2521 err = -EAGAIN;
2522 if (!req->rq_reply_bytes_recvd)
2523 goto out;
2524
2525 req->rq_rcv_buf.len = req->rq_private_buf.len;
2526 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2527
2528 /* Check that the softirq receive buffer is valid */
2529 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2530 sizeof(req->rq_rcv_buf)) != 0);
2531
2532 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2533 req->rq_rcv_buf.head[0].iov_base, req);
2534 err = rpc_decode_header(task, &xdr);
2535out:
2536 switch (err) {
2537 case 0:
2538 task->tk_action = rpc_exit_task;
2539 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2540 dprintk("RPC: %5u %s result %d\n",
2541 task->tk_pid, __func__, task->tk_status);
2542 return;
2543 case -EAGAIN:
2544 task->tk_status = 0;
2545 if (task->tk_client->cl_discrtry)
2546 xprt_conditional_disconnect(req->rq_xprt,
2547 req->rq_connect_cookie);
2548 task->tk_action = call_encode;
2549 rpc_check_timeout(task);
2550 break;
2551 case -EKEYREJECTED:
2552 task->tk_action = call_reserve;
2553 rpc_check_timeout(task);
2554 rpcauth_invalcred(task);
2555 /* Ensure we obtain a new XID if we retry! */
2556 xprt_release(task);
2557 }
2558}
2559
2560static int
2561rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2562{
2563 struct rpc_clnt *clnt = task->tk_client;
2564 struct rpc_rqst *req = task->tk_rqstp;
2565 __be32 *p;
2566 int error;
2567
2568 error = -EMSGSIZE;
2569 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2570 if (!p)
2571 goto out_fail;
2572 *p++ = req->rq_xid;
2573 *p++ = rpc_call;
2574 *p++ = cpu_to_be32(RPC_VERSION);
2575 *p++ = cpu_to_be32(clnt->cl_prog);
2576 *p++ = cpu_to_be32(clnt->cl_vers);
2577 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2578
2579 error = rpcauth_marshcred(task, xdr);
2580 if (error < 0)
2581 goto out_fail;
2582 return 0;
2583out_fail:
2584 trace_rpc_bad_callhdr(task);
2585 rpc_call_rpcerror(task, error);
2586 return error;
2587}
2588
2589static noinline int
2590rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2591{
2592 struct rpc_clnt *clnt = task->tk_client;
2593 int error;
2594 __be32 *p;
2595
2596 /* RFC-1014 says that the representation of XDR data must be a
2597 * multiple of four bytes
2598 * - if it isn't pointer subtraction in the NFS client may give
2599 * undefined results
2600 */
2601 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2602 goto out_unparsable;
2603
2604 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2605 if (!p)
2606 goto out_unparsable;
2607 p++; /* skip XID */
2608 if (*p++ != rpc_reply)
2609 goto out_unparsable;
2610 if (*p++ != rpc_msg_accepted)
2611 goto out_msg_denied;
2612
2613 error = rpcauth_checkverf(task, xdr);
2614 if (error)
2615 goto out_verifier;
2616
2617 p = xdr_inline_decode(xdr, sizeof(*p));
2618 if (!p)
2619 goto out_unparsable;
2620 switch (*p) {
2621 case rpc_success:
2622 return 0;
2623 case rpc_prog_unavail:
2624 trace_rpc__prog_unavail(task);
2625 error = -EPFNOSUPPORT;
2626 goto out_err;
2627 case rpc_prog_mismatch:
2628 trace_rpc__prog_mismatch(task);
2629 error = -EPROTONOSUPPORT;
2630 goto out_err;
2631 case rpc_proc_unavail:
2632 trace_rpc__proc_unavail(task);
2633 error = -EOPNOTSUPP;
2634 goto out_err;
2635 case rpc_garbage_args:
2636 case rpc_system_err:
2637 trace_rpc__garbage_args(task);
2638 error = -EIO;
2639 break;
2640 default:
2641 goto out_unparsable;
2642 }
2643
2644out_garbage:
2645 clnt->cl_stats->rpcgarbage++;
2646 if (task->tk_garb_retry) {
2647 task->tk_garb_retry--;
2648 task->tk_action = call_encode;
2649 return -EAGAIN;
2650 }
2651out_err:
2652 rpc_call_rpcerror(task, error);
2653 return error;
2654
2655out_unparsable:
2656 trace_rpc__unparsable(task);
2657 error = -EIO;
2658 goto out_garbage;
2659
2660out_verifier:
2661 trace_rpc_bad_verifier(task);
2662 goto out_garbage;
2663
2664out_msg_denied:
2665 error = -EACCES;
2666 p = xdr_inline_decode(xdr, sizeof(*p));
2667 if (!p)
2668 goto out_unparsable;
2669 switch (*p++) {
2670 case rpc_auth_error:
2671 break;
2672 case rpc_mismatch:
2673 trace_rpc__mismatch(task);
2674 error = -EPROTONOSUPPORT;
2675 goto out_err;
2676 default:
2677 goto out_unparsable;
2678 }
2679
2680 p = xdr_inline_decode(xdr, sizeof(*p));
2681 if (!p)
2682 goto out_unparsable;
2683 switch (*p++) {
2684 case rpc_autherr_rejectedcred:
2685 case rpc_autherr_rejectedverf:
2686 case rpcsec_gsserr_credproblem:
2687 case rpcsec_gsserr_ctxproblem:
2688 if (!task->tk_cred_retry)
2689 break;
2690 task->tk_cred_retry--;
2691 trace_rpc__stale_creds(task);
2692 return -EKEYREJECTED;
2693 case rpc_autherr_badcred:
2694 case rpc_autherr_badverf:
2695 /* possibly garbled cred/verf? */
2696 if (!task->tk_garb_retry)
2697 break;
2698 task->tk_garb_retry--;
2699 trace_rpc__bad_creds(task);
2700 task->tk_action = call_encode;
2701 return -EAGAIN;
2702 case rpc_autherr_tooweak:
2703 trace_rpc__auth_tooweak(task);
2704 pr_warn("RPC: server %s requires stronger authentication.\n",
2705 task->tk_xprt->servername);
2706 break;
2707 default:
2708 goto out_unparsable;
2709 }
2710 goto out_err;
2711}
2712
2713static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2714 const void *obj)
2715{
2716}
2717
2718static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2719 void *obj)
2720{
2721 return 0;
2722}
2723
2724static const struct rpc_procinfo rpcproc_null = {
2725 .p_encode = rpcproc_encode_null,
2726 .p_decode = rpcproc_decode_null,
2727};
2728
2729static int rpc_ping(struct rpc_clnt *clnt)
2730{
2731 struct rpc_message msg = {
2732 .rpc_proc = &rpcproc_null,
2733 };
2734 int err;
2735 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2736 RPC_TASK_NULLCREDS);
2737 return err;
2738}
2739
2740static
2741struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2742 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2743 const struct rpc_call_ops *ops, void *data)
2744{
2745 struct rpc_message msg = {
2746 .rpc_proc = &rpcproc_null,
2747 };
2748 struct rpc_task_setup task_setup_data = {
2749 .rpc_client = clnt,
2750 .rpc_xprt = xprt,
2751 .rpc_message = &msg,
2752 .rpc_op_cred = cred,
2753 .callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
2754 .callback_data = data,
2755 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2756 RPC_TASK_NULLCREDS,
2757 };
2758
2759 return rpc_run_task(&task_setup_data);
2760}
2761
2762struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2763{
2764 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2765}
2766EXPORT_SYMBOL_GPL(rpc_call_null);
2767
2768struct rpc_cb_add_xprt_calldata {
2769 struct rpc_xprt_switch *xps;
2770 struct rpc_xprt *xprt;
2771};
2772
2773static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2774{
2775 struct rpc_cb_add_xprt_calldata *data = calldata;
2776
2777 if (task->tk_status == 0)
2778 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2779}
2780
2781static void rpc_cb_add_xprt_release(void *calldata)
2782{
2783 struct rpc_cb_add_xprt_calldata *data = calldata;
2784
2785 xprt_put(data->xprt);
2786 xprt_switch_put(data->xps);
2787 kfree(data);
2788}
2789
2790static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2791 .rpc_call_done = rpc_cb_add_xprt_done,
2792 .rpc_release = rpc_cb_add_xprt_release,
2793};
2794
2795/**
2796 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2797 * @clnt: pointer to struct rpc_clnt
2798 * @xps: pointer to struct rpc_xprt_switch,
2799 * @xprt: pointer struct rpc_xprt
2800 * @dummy: unused
2801 */
2802int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2803 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2804 void *dummy)
2805{
2806 struct rpc_cb_add_xprt_calldata *data;
2807 struct rpc_task *task;
2808
2809 data = kmalloc(sizeof(*data), GFP_NOFS);
2810 if (!data)
2811 return -ENOMEM;
2812 data->xps = xprt_switch_get(xps);
2813 data->xprt = xprt_get(xprt);
2814 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2815 rpc_cb_add_xprt_release(data);
2816 goto success;
2817 }
2818
2819 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2820 &rpc_cb_add_xprt_call_ops, data);
2821
2822 rpc_put_task(task);
2823success:
2824 return 1;
2825}
2826EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2827
2828/**
2829 * rpc_clnt_setup_test_and_add_xprt()
2830 *
2831 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2832 * 1) caller of the test function must dereference the rpc_xprt_switch
2833 * and the rpc_xprt.
2834 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2835 * the rpc_call_done routine.
2836 *
2837 * Upon success (return of 1), the test function adds the new
2838 * transport to the rpc_clnt xprt switch
2839 *
2840 * @clnt: struct rpc_clnt to get the new transport
2841 * @xps: the rpc_xprt_switch to hold the new transport
2842 * @xprt: the rpc_xprt to test
2843 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2844 * and test function call data
2845 */
2846int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2847 struct rpc_xprt_switch *xps,
2848 struct rpc_xprt *xprt,
2849 void *data)
2850{
2851 struct rpc_task *task;
2852 struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
2853 int status = -EADDRINUSE;
2854
2855 xprt = xprt_get(xprt);
2856 xprt_switch_get(xps);
2857
2858 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2859 goto out_err;
2860
2861 /* Test the connection */
2862 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2863 if (IS_ERR(task)) {
2864 status = PTR_ERR(task);
2865 goto out_err;
2866 }
2867 status = task->tk_status;
2868 rpc_put_task(task);
2869
2870 if (status < 0)
2871 goto out_err;
2872
2873 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2874 xtest->add_xprt_test(clnt, xprt, xtest->data);
2875
2876 xprt_put(xprt);
2877 xprt_switch_put(xps);
2878
2879 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
2880 return 1;
2881out_err:
2882 xprt_put(xprt);
2883 xprt_switch_put(xps);
2884 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n",
2885 status, xprt->address_strings[RPC_DISPLAY_ADDR]);
2886 return status;
2887}
2888EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
2889
2890/**
2891 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
2892 * @clnt: pointer to struct rpc_clnt
2893 * @xprtargs: pointer to struct xprt_create
2894 * @setup: callback to test and/or set up the connection
2895 * @data: pointer to setup function data
2896 *
2897 * Creates a new transport using the parameters set in args and
2898 * adds it to clnt.
2899 * If ping is set, then test that connectivity succeeds before
2900 * adding the new transport.
2901 *
2902 */
2903int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
2904 struct xprt_create *xprtargs,
2905 int (*setup)(struct rpc_clnt *,
2906 struct rpc_xprt_switch *,
2907 struct rpc_xprt *,
2908 void *),
2909 void *data)
2910{
2911 struct rpc_xprt_switch *xps;
2912 struct rpc_xprt *xprt;
2913 unsigned long connect_timeout;
2914 unsigned long reconnect_timeout;
2915 unsigned char resvport, reuseport;
2916 int ret = 0;
2917
2918 rcu_read_lock();
2919 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2920 xprt = xprt_iter_xprt(&clnt->cl_xpi);
2921 if (xps == NULL || xprt == NULL) {
2922 rcu_read_unlock();
2923 xprt_switch_put(xps);
2924 return -EAGAIN;
2925 }
2926 resvport = xprt->resvport;
2927 reuseport = xprt->reuseport;
2928 connect_timeout = xprt->connect_timeout;
2929 reconnect_timeout = xprt->max_reconnect_timeout;
2930 rcu_read_unlock();
2931
2932 xprt = xprt_create_transport(xprtargs);
2933 if (IS_ERR(xprt)) {
2934 ret = PTR_ERR(xprt);
2935 goto out_put_switch;
2936 }
2937 xprt->resvport = resvport;
2938 xprt->reuseport = reuseport;
2939 if (xprt->ops->set_connect_timeout != NULL)
2940 xprt->ops->set_connect_timeout(xprt,
2941 connect_timeout,
2942 reconnect_timeout);
2943
2944 rpc_xprt_switch_set_roundrobin(xps);
2945 if (setup) {
2946 ret = setup(clnt, xps, xprt, data);
2947 if (ret != 0)
2948 goto out_put_xprt;
2949 }
2950 rpc_xprt_switch_add_xprt(xps, xprt);
2951out_put_xprt:
2952 xprt_put(xprt);
2953out_put_switch:
2954 xprt_switch_put(xps);
2955 return ret;
2956}
2957EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
2958
2959struct connect_timeout_data {
2960 unsigned long connect_timeout;
2961 unsigned long reconnect_timeout;
2962};
2963
2964static int
2965rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
2966 struct rpc_xprt *xprt,
2967 void *data)
2968{
2969 struct connect_timeout_data *timeo = data;
2970
2971 if (xprt->ops->set_connect_timeout)
2972 xprt->ops->set_connect_timeout(xprt,
2973 timeo->connect_timeout,
2974 timeo->reconnect_timeout);
2975 return 0;
2976}
2977
2978void
2979rpc_set_connect_timeout(struct rpc_clnt *clnt,
2980 unsigned long connect_timeout,
2981 unsigned long reconnect_timeout)
2982{
2983 struct connect_timeout_data timeout = {
2984 .connect_timeout = connect_timeout,
2985 .reconnect_timeout = reconnect_timeout,
2986 };
2987 rpc_clnt_iterate_for_each_xprt(clnt,
2988 rpc_xprt_set_connect_timeout,
2989 &timeout);
2990}
2991EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
2992
2993void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
2994{
2995 rcu_read_lock();
2996 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2997 rcu_read_unlock();
2998}
2999EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
3000
3001void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3002{
3003 rcu_read_lock();
3004 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3005 xprt);
3006 rcu_read_unlock();
3007}
3008EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3009
3010bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3011 const struct sockaddr *sap)
3012{
3013 struct rpc_xprt_switch *xps;
3014 bool ret;
3015
3016 rcu_read_lock();
3017 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3018 ret = rpc_xprt_switch_has_addr(xps, sap);
3019 rcu_read_unlock();
3020 return ret;
3021}
3022EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3023
3024#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3025static void rpc_show_header(void)
3026{
3027 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3028 "-timeout ---ops--\n");
3029}
3030
3031static void rpc_show_task(const struct rpc_clnt *clnt,
3032 const struct rpc_task *task)
3033{
3034 const char *rpc_waitq = "none";
3035
3036 if (RPC_IS_QUEUED(task))
3037 rpc_waitq = rpc_qname(task->tk_waitqueue);
3038
3039 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3040 task->tk_pid, task->tk_flags, task->tk_status,
3041 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3042 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3043 task->tk_action, rpc_waitq);
3044}
3045
3046void rpc_show_tasks(struct net *net)
3047{
3048 struct rpc_clnt *clnt;
3049 struct rpc_task *task;
3050 int header = 0;
3051 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3052
3053 spin_lock(&sn->rpc_client_lock);
3054 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3055 spin_lock(&clnt->cl_lock);
3056 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3057 if (!header) {
3058 rpc_show_header();
3059 header++;
3060 }
3061 rpc_show_task(clnt, task);
3062 }
3063 spin_unlock(&clnt->cl_lock);
3064 }
3065 spin_unlock(&sn->rpc_client_lock);
3066}
3067#endif
3068
3069#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3070static int
3071rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3072 struct rpc_xprt *xprt,
3073 void *dummy)
3074{
3075 return xprt_enable_swap(xprt);
3076}
3077
3078int
3079rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3080{
3081 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3082 return rpc_clnt_iterate_for_each_xprt(clnt,
3083 rpc_clnt_swap_activate_callback, NULL);
3084 return 0;
3085}
3086EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3087
3088static int
3089rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3090 struct rpc_xprt *xprt,
3091 void *dummy)
3092{
3093 xprt_disable_swap(xprt);
3094 return 0;
3095}
3096
3097void
3098rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3099{
3100 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3101 rpc_clnt_iterate_for_each_xprt(clnt,
3102 rpc_clnt_swap_deactivate_callback, NULL);
3103}
3104EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3105#endif /* CONFIG_SUNRPC_SWAP */
1// 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 __rpc_clnt_remove_pipedir(clnt);
115 rpc_put_sb_net(net);
116 }
117}
118
119static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
120 struct rpc_clnt *clnt)
121{
122 static uint32_t clntid;
123 const char *dir_name = clnt->cl_program->pipe_dir_name;
124 char name[15];
125 struct dentry *dir, *dentry;
126
127 dir = rpc_d_lookup_sb(sb, dir_name);
128 if (dir == NULL) {
129 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
130 return dir;
131 }
132 for (;;) {
133 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
134 name[sizeof(name) - 1] = '\0';
135 dentry = rpc_create_client_dir(dir, name, clnt);
136 if (!IS_ERR(dentry))
137 break;
138 if (dentry == ERR_PTR(-EEXIST))
139 continue;
140 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
141 " %s/%s, error %ld\n",
142 dir_name, name, PTR_ERR(dentry));
143 break;
144 }
145 dput(dir);
146 return dentry;
147}
148
149static int
150rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
151{
152 struct dentry *dentry;
153
154 if (clnt->cl_program->pipe_dir_name != NULL) {
155 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
156 if (IS_ERR(dentry))
157 return PTR_ERR(dentry);
158 }
159 return 0;
160}
161
162static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
163{
164 if (clnt->cl_program->pipe_dir_name == NULL)
165 return 1;
166
167 switch (event) {
168 case RPC_PIPEFS_MOUNT:
169 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
170 return 1;
171 if (refcount_read(&clnt->cl_count) == 0)
172 return 1;
173 break;
174 case RPC_PIPEFS_UMOUNT:
175 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
176 return 1;
177 break;
178 }
179 return 0;
180}
181
182static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
183 struct super_block *sb)
184{
185 struct dentry *dentry;
186
187 switch (event) {
188 case RPC_PIPEFS_MOUNT:
189 dentry = rpc_setup_pipedir_sb(sb, clnt);
190 if (!dentry)
191 return -ENOENT;
192 if (IS_ERR(dentry))
193 return PTR_ERR(dentry);
194 break;
195 case RPC_PIPEFS_UMOUNT:
196 __rpc_clnt_remove_pipedir(clnt);
197 break;
198 default:
199 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
200 return -ENOTSUPP;
201 }
202 return 0;
203}
204
205static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
206 struct super_block *sb)
207{
208 int error = 0;
209
210 for (;; clnt = clnt->cl_parent) {
211 if (!rpc_clnt_skip_event(clnt, event))
212 error = __rpc_clnt_handle_event(clnt, event, sb);
213 if (error || clnt == clnt->cl_parent)
214 break;
215 }
216 return error;
217}
218
219static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
220{
221 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
222 struct rpc_clnt *clnt;
223
224 spin_lock(&sn->rpc_client_lock);
225 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
226 if (rpc_clnt_skip_event(clnt, event))
227 continue;
228 spin_unlock(&sn->rpc_client_lock);
229 return clnt;
230 }
231 spin_unlock(&sn->rpc_client_lock);
232 return NULL;
233}
234
235static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
236 void *ptr)
237{
238 struct super_block *sb = ptr;
239 struct rpc_clnt *clnt;
240 int error = 0;
241
242 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
243 error = __rpc_pipefs_event(clnt, event, sb);
244 if (error)
245 break;
246 }
247 return error;
248}
249
250static struct notifier_block rpc_clients_block = {
251 .notifier_call = rpc_pipefs_event,
252 .priority = SUNRPC_PIPEFS_RPC_PRIO,
253};
254
255int rpc_clients_notifier_register(void)
256{
257 return rpc_pipefs_notifier_register(&rpc_clients_block);
258}
259
260void rpc_clients_notifier_unregister(void)
261{
262 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
263}
264
265static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
266 struct rpc_xprt *xprt,
267 const struct rpc_timeout *timeout)
268{
269 struct rpc_xprt *old;
270
271 spin_lock(&clnt->cl_lock);
272 old = rcu_dereference_protected(clnt->cl_xprt,
273 lockdep_is_held(&clnt->cl_lock));
274
275 if (!xprt_bound(xprt))
276 clnt->cl_autobind = 1;
277
278 clnt->cl_timeout = timeout;
279 rcu_assign_pointer(clnt->cl_xprt, xprt);
280 spin_unlock(&clnt->cl_lock);
281
282 return old;
283}
284
285static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
286{
287 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
288 nodename, sizeof(clnt->cl_nodename));
289}
290
291static int rpc_client_register(struct rpc_clnt *clnt,
292 rpc_authflavor_t pseudoflavor,
293 const char *client_name)
294{
295 struct rpc_auth_create_args auth_args = {
296 .pseudoflavor = pseudoflavor,
297 .target_name = client_name,
298 };
299 struct rpc_auth *auth;
300 struct net *net = rpc_net_ns(clnt);
301 struct super_block *pipefs_sb;
302 int err;
303
304 rpc_clnt_debugfs_register(clnt);
305
306 pipefs_sb = rpc_get_sb_net(net);
307 if (pipefs_sb) {
308 err = rpc_setup_pipedir(pipefs_sb, clnt);
309 if (err)
310 goto out;
311 }
312
313 rpc_register_client(clnt);
314 if (pipefs_sb)
315 rpc_put_sb_net(net);
316
317 auth = rpcauth_create(&auth_args, clnt);
318 if (IS_ERR(auth)) {
319 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
320 pseudoflavor);
321 err = PTR_ERR(auth);
322 goto err_auth;
323 }
324 return 0;
325err_auth:
326 pipefs_sb = rpc_get_sb_net(net);
327 rpc_unregister_client(clnt);
328 __rpc_clnt_remove_pipedir(clnt);
329out:
330 if (pipefs_sb)
331 rpc_put_sb_net(net);
332 rpc_sysfs_client_destroy(clnt);
333 rpc_clnt_debugfs_unregister(clnt);
334 return err;
335}
336
337static DEFINE_IDA(rpc_clids);
338
339void rpc_cleanup_clids(void)
340{
341 ida_destroy(&rpc_clids);
342}
343
344static int rpc_alloc_clid(struct rpc_clnt *clnt)
345{
346 int clid;
347
348 clid = ida_alloc(&rpc_clids, GFP_KERNEL);
349 if (clid < 0)
350 return clid;
351 clnt->cl_clid = clid;
352 return 0;
353}
354
355static void rpc_free_clid(struct rpc_clnt *clnt)
356{
357 ida_free(&rpc_clids, clnt->cl_clid);
358}
359
360static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
361 struct rpc_xprt_switch *xps,
362 struct rpc_xprt *xprt,
363 struct rpc_clnt *parent)
364{
365 const struct rpc_program *program = args->program;
366 const struct rpc_version *version;
367 struct rpc_clnt *clnt = NULL;
368 const struct rpc_timeout *timeout;
369 const char *nodename = args->nodename;
370 int err;
371
372 err = rpciod_up();
373 if (err)
374 goto out_no_rpciod;
375
376 err = -EINVAL;
377 if (args->version >= program->nrvers)
378 goto out_err;
379 version = program->version[args->version];
380 if (version == NULL)
381 goto out_err;
382
383 err = -ENOMEM;
384 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
385 if (!clnt)
386 goto out_err;
387 clnt->cl_parent = parent ? : clnt;
388
389 err = rpc_alloc_clid(clnt);
390 if (err)
391 goto out_no_clid;
392
393 clnt->cl_cred = get_cred(args->cred);
394 clnt->cl_procinfo = version->procs;
395 clnt->cl_maxproc = version->nrprocs;
396 clnt->cl_prog = args->prognumber ? : program->number;
397 clnt->cl_vers = version->number;
398 clnt->cl_stats = program->stats;
399 clnt->cl_metrics = rpc_alloc_iostats(clnt);
400 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
401 err = -ENOMEM;
402 if (clnt->cl_metrics == NULL)
403 goto out_no_stats;
404 clnt->cl_program = program;
405 INIT_LIST_HEAD(&clnt->cl_tasks);
406 spin_lock_init(&clnt->cl_lock);
407
408 timeout = xprt->timeout;
409 if (args->timeout != NULL) {
410 memcpy(&clnt->cl_timeout_default, args->timeout,
411 sizeof(clnt->cl_timeout_default));
412 timeout = &clnt->cl_timeout_default;
413 }
414
415 rpc_clnt_set_transport(clnt, xprt, timeout);
416 xprt->main = true;
417 xprt_iter_init(&clnt->cl_xpi, xps);
418 xprt_switch_put(xps);
419
420 clnt->cl_rtt = &clnt->cl_rtt_default;
421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
422
423 refcount_set(&clnt->cl_count, 1);
424
425 if (nodename == NULL)
426 nodename = utsname()->nodename;
427 /* save the nodename */
428 rpc_clnt_set_nodename(clnt, nodename);
429
430 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
431 err = rpc_client_register(clnt, args->authflavor, args->client_name);
432 if (err)
433 goto out_no_path;
434 if (parent)
435 refcount_inc(&parent->cl_count);
436
437 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
438 return clnt;
439
440out_no_path:
441 rpc_free_iostats(clnt->cl_metrics);
442out_no_stats:
443 put_cred(clnt->cl_cred);
444 rpc_free_clid(clnt);
445out_no_clid:
446 kfree(clnt);
447out_err:
448 rpciod_down();
449out_no_rpciod:
450 xprt_switch_put(xps);
451 xprt_put(xprt);
452 trace_rpc_clnt_new_err(program->name, args->servername, err);
453 return ERR_PTR(err);
454}
455
456static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
457 struct rpc_xprt *xprt)
458{
459 struct rpc_clnt *clnt = NULL;
460 struct rpc_xprt_switch *xps;
461
462 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
463 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
464 xps = args->bc_xprt->xpt_bc_xps;
465 xprt_switch_get(xps);
466 } else {
467 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
468 if (xps == NULL) {
469 xprt_put(xprt);
470 return ERR_PTR(-ENOMEM);
471 }
472 if (xprt->bc_xprt) {
473 xprt_switch_get(xps);
474 xprt->bc_xprt->xpt_bc_xps = xps;
475 }
476 }
477 clnt = rpc_new_client(args, xps, xprt, NULL);
478 if (IS_ERR(clnt))
479 return clnt;
480
481 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
482 int err = rpc_ping(clnt);
483 if (err != 0) {
484 rpc_shutdown_client(clnt);
485 return ERR_PTR(err);
486 }
487 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
488 int err = rpc_ping_noreply(clnt);
489 if (err != 0) {
490 rpc_shutdown_client(clnt);
491 return ERR_PTR(err);
492 }
493 }
494
495 clnt->cl_softrtry = 1;
496 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
497 clnt->cl_softrtry = 0;
498 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
499 clnt->cl_softerr = 1;
500 }
501
502 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
503 clnt->cl_autobind = 1;
504 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
505 clnt->cl_noretranstimeo = 1;
506 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
507 clnt->cl_discrtry = 1;
508 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
509 clnt->cl_chatty = 1;
510
511 return clnt;
512}
513
514/**
515 * rpc_create - create an RPC client and transport with one call
516 * @args: rpc_clnt create argument structure
517 *
518 * Creates and initializes an RPC transport and an RPC client.
519 *
520 * It can ping the server in order to determine if it is up, and to see if
521 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
522 * this behavior so asynchronous tasks can also use rpc_create.
523 */
524struct rpc_clnt *rpc_create(struct rpc_create_args *args)
525{
526 struct rpc_xprt *xprt;
527 struct xprt_create xprtargs = {
528 .net = args->net,
529 .ident = args->protocol,
530 .srcaddr = args->saddress,
531 .dstaddr = args->address,
532 .addrlen = args->addrsize,
533 .servername = args->servername,
534 .bc_xprt = args->bc_xprt,
535 };
536 char servername[48];
537 struct rpc_clnt *clnt;
538 int i;
539
540 if (args->bc_xprt) {
541 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
542 xprt = args->bc_xprt->xpt_bc_xprt;
543 if (xprt) {
544 xprt_get(xprt);
545 return rpc_create_xprt(args, xprt);
546 }
547 }
548
549 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
550 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
551 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
552 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
553 /*
554 * If the caller chooses not to specify a hostname, whip
555 * up a string representation of the passed-in address.
556 */
557 if (xprtargs.servername == NULL) {
558 struct sockaddr_un *sun =
559 (struct sockaddr_un *)args->address;
560 struct sockaddr_in *sin =
561 (struct sockaddr_in *)args->address;
562 struct sockaddr_in6 *sin6 =
563 (struct sockaddr_in6 *)args->address;
564
565 servername[0] = '\0';
566 switch (args->address->sa_family) {
567 case AF_LOCAL:
568 snprintf(servername, sizeof(servername), "%s",
569 sun->sun_path);
570 break;
571 case AF_INET:
572 snprintf(servername, sizeof(servername), "%pI4",
573 &sin->sin_addr.s_addr);
574 break;
575 case AF_INET6:
576 snprintf(servername, sizeof(servername), "%pI6",
577 &sin6->sin6_addr);
578 break;
579 default:
580 /* caller wants default server name, but
581 * address family isn't recognized. */
582 return ERR_PTR(-EINVAL);
583 }
584 xprtargs.servername = servername;
585 }
586
587 xprt = xprt_create_transport(&xprtargs);
588 if (IS_ERR(xprt))
589 return (struct rpc_clnt *)xprt;
590
591 /*
592 * By default, kernel RPC client connects from a reserved port.
593 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
594 * but it is always enabled for rpciod, which handles the connect
595 * operation.
596 */
597 xprt->resvport = 1;
598 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
599 xprt->resvport = 0;
600 xprt->reuseport = 0;
601 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
602 xprt->reuseport = 1;
603
604 clnt = rpc_create_xprt(args, xprt);
605 if (IS_ERR(clnt) || args->nconnect <= 1)
606 return clnt;
607
608 for (i = 0; i < args->nconnect - 1; i++) {
609 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
610 break;
611 }
612 return clnt;
613}
614EXPORT_SYMBOL_GPL(rpc_create);
615
616/*
617 * This function clones the RPC client structure. It allows us to share the
618 * same transport while varying parameters such as the authentication
619 * flavour.
620 */
621static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
622 struct rpc_clnt *clnt)
623{
624 struct rpc_xprt_switch *xps;
625 struct rpc_xprt *xprt;
626 struct rpc_clnt *new;
627 int err;
628
629 err = -ENOMEM;
630 rcu_read_lock();
631 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
632 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
633 rcu_read_unlock();
634 if (xprt == NULL || xps == NULL) {
635 xprt_put(xprt);
636 xprt_switch_put(xps);
637 goto out_err;
638 }
639 args->servername = xprt->servername;
640 args->nodename = clnt->cl_nodename;
641
642 new = rpc_new_client(args, xps, xprt, clnt);
643 if (IS_ERR(new))
644 return new;
645
646 /* Turn off autobind on clones */
647 new->cl_autobind = 0;
648 new->cl_softrtry = clnt->cl_softrtry;
649 new->cl_softerr = clnt->cl_softerr;
650 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
651 new->cl_discrtry = clnt->cl_discrtry;
652 new->cl_chatty = clnt->cl_chatty;
653 new->cl_principal = clnt->cl_principal;
654 new->cl_max_connect = clnt->cl_max_connect;
655 return new;
656
657out_err:
658 trace_rpc_clnt_clone_err(clnt, err);
659 return ERR_PTR(err);
660}
661
662/**
663 * rpc_clone_client - Clone an RPC client structure
664 *
665 * @clnt: RPC client whose parameters are copied
666 *
667 * Returns a fresh RPC client or an ERR_PTR.
668 */
669struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
670{
671 struct rpc_create_args args = {
672 .program = clnt->cl_program,
673 .prognumber = clnt->cl_prog,
674 .version = clnt->cl_vers,
675 .authflavor = clnt->cl_auth->au_flavor,
676 .cred = clnt->cl_cred,
677 };
678 return __rpc_clone_client(&args, clnt);
679}
680EXPORT_SYMBOL_GPL(rpc_clone_client);
681
682/**
683 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
684 *
685 * @clnt: RPC client whose parameters are copied
686 * @flavor: security flavor for new client
687 *
688 * Returns a fresh RPC client or an ERR_PTR.
689 */
690struct rpc_clnt *
691rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
692{
693 struct rpc_create_args args = {
694 .program = clnt->cl_program,
695 .prognumber = clnt->cl_prog,
696 .version = clnt->cl_vers,
697 .authflavor = flavor,
698 .cred = clnt->cl_cred,
699 };
700 return __rpc_clone_client(&args, clnt);
701}
702EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
703
704/**
705 * rpc_switch_client_transport: switch the RPC transport on the fly
706 * @clnt: pointer to a struct rpc_clnt
707 * @args: pointer to the new transport arguments
708 * @timeout: pointer to the new timeout parameters
709 *
710 * This function allows the caller to switch the RPC transport for the
711 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
712 * server, for instance. It assumes that the caller has ensured that
713 * there are no active RPC tasks by using some form of locking.
714 *
715 * Returns zero if "clnt" is now using the new xprt. Otherwise a
716 * negative errno is returned, and "clnt" continues to use the old
717 * xprt.
718 */
719int rpc_switch_client_transport(struct rpc_clnt *clnt,
720 struct xprt_create *args,
721 const struct rpc_timeout *timeout)
722{
723 const struct rpc_timeout *old_timeo;
724 rpc_authflavor_t pseudoflavor;
725 struct rpc_xprt_switch *xps, *oldxps;
726 struct rpc_xprt *xprt, *old;
727 struct rpc_clnt *parent;
728 int err;
729
730 xprt = xprt_create_transport(args);
731 if (IS_ERR(xprt))
732 return PTR_ERR(xprt);
733
734 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
735 if (xps == NULL) {
736 xprt_put(xprt);
737 return -ENOMEM;
738 }
739
740 pseudoflavor = clnt->cl_auth->au_flavor;
741
742 old_timeo = clnt->cl_timeout;
743 old = rpc_clnt_set_transport(clnt, xprt, timeout);
744 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
745
746 rpc_unregister_client(clnt);
747 __rpc_clnt_remove_pipedir(clnt);
748 rpc_sysfs_client_destroy(clnt);
749 rpc_clnt_debugfs_unregister(clnt);
750
751 /*
752 * A new transport was created. "clnt" therefore
753 * becomes the root of a new cl_parent tree. clnt's
754 * children, if it has any, still point to the old xprt.
755 */
756 parent = clnt->cl_parent;
757 clnt->cl_parent = clnt;
758
759 /*
760 * The old rpc_auth cache cannot be re-used. GSS
761 * contexts in particular are between a single
762 * client and server.
763 */
764 err = rpc_client_register(clnt, pseudoflavor, NULL);
765 if (err)
766 goto out_revert;
767
768 synchronize_rcu();
769 if (parent != clnt)
770 rpc_release_client(parent);
771 xprt_switch_put(oldxps);
772 xprt_put(old);
773 trace_rpc_clnt_replace_xprt(clnt);
774 return 0;
775
776out_revert:
777 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
778 rpc_clnt_set_transport(clnt, old, old_timeo);
779 clnt->cl_parent = parent;
780 rpc_client_register(clnt, pseudoflavor, NULL);
781 xprt_switch_put(xps);
782 xprt_put(xprt);
783 trace_rpc_clnt_replace_xprt_err(clnt);
784 return err;
785}
786EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
787
788static
789int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
790 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
791{
792 struct rpc_xprt_switch *xps;
793
794 rcu_read_lock();
795 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
796 rcu_read_unlock();
797 if (xps == NULL)
798 return -EAGAIN;
799 func(xpi, xps);
800 xprt_switch_put(xps);
801 return 0;
802}
803
804static
805int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
806{
807 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
808}
809
810static
811int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
812 struct rpc_xprt_iter *xpi)
813{
814 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
815}
816
817/**
818 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
819 * @clnt: pointer to client
820 * @fn: function to apply
821 * @data: void pointer to function data
822 *
823 * Iterates through the list of RPC transports currently attached to the
824 * client and applies the function fn(clnt, xprt, data).
825 *
826 * On error, the iteration stops, and the function returns the error value.
827 */
828int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
829 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
830 void *data)
831{
832 struct rpc_xprt_iter xpi;
833 int ret;
834
835 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
836 if (ret)
837 return ret;
838 for (;;) {
839 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
840
841 if (!xprt)
842 break;
843 ret = fn(clnt, xprt, data);
844 xprt_put(xprt);
845 if (ret < 0)
846 break;
847 }
848 xprt_iter_destroy(&xpi);
849 return ret;
850}
851EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
852
853/*
854 * Kill all tasks for the given client.
855 * XXX: kill their descendants as well?
856 */
857void rpc_killall_tasks(struct rpc_clnt *clnt)
858{
859 struct rpc_task *rovr;
860
861
862 if (list_empty(&clnt->cl_tasks))
863 return;
864
865 /*
866 * Spin lock all_tasks to prevent changes...
867 */
868 trace_rpc_clnt_killall(clnt);
869 spin_lock(&clnt->cl_lock);
870 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
871 rpc_signal_task(rovr);
872 spin_unlock(&clnt->cl_lock);
873}
874EXPORT_SYMBOL_GPL(rpc_killall_tasks);
875
876/**
877 * rpc_cancel_tasks - try to cancel a set of RPC tasks
878 * @clnt: Pointer to RPC client
879 * @error: RPC task error value to set
880 * @fnmatch: Pointer to selector function
881 * @data: User data
882 *
883 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
884 * The argument @error must be a negative error value.
885 */
886unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
887 bool (*fnmatch)(const struct rpc_task *,
888 const void *),
889 const void *data)
890{
891 struct rpc_task *task;
892 unsigned long count = 0;
893
894 if (list_empty(&clnt->cl_tasks))
895 return 0;
896 /*
897 * Spin lock all_tasks to prevent changes...
898 */
899 spin_lock(&clnt->cl_lock);
900 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
901 if (!RPC_IS_ACTIVATED(task))
902 continue;
903 if (!fnmatch(task, data))
904 continue;
905 rpc_task_try_cancel(task, error);
906 count++;
907 }
908 spin_unlock(&clnt->cl_lock);
909 return count;
910}
911EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
912
913static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
914 struct rpc_xprt *xprt, void *dummy)
915{
916 if (xprt_connected(xprt))
917 xprt_force_disconnect(xprt);
918 return 0;
919}
920
921void rpc_clnt_disconnect(struct rpc_clnt *clnt)
922{
923 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
924}
925EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
926
927/*
928 * Properly shut down an RPC client, terminating all outstanding
929 * requests.
930 */
931void rpc_shutdown_client(struct rpc_clnt *clnt)
932{
933 might_sleep();
934
935 trace_rpc_clnt_shutdown(clnt);
936
937 while (!list_empty(&clnt->cl_tasks)) {
938 rpc_killall_tasks(clnt);
939 wait_event_timeout(destroy_wait,
940 list_empty(&clnt->cl_tasks), 1*HZ);
941 }
942
943 rpc_release_client(clnt);
944}
945EXPORT_SYMBOL_GPL(rpc_shutdown_client);
946
947/*
948 * Free an RPC client
949 */
950static void rpc_free_client_work(struct work_struct *work)
951{
952 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
953
954 trace_rpc_clnt_free(clnt);
955
956 /* These might block on processes that might allocate memory,
957 * so they cannot be called in rpciod, so they are handled separately
958 * here.
959 */
960 rpc_sysfs_client_destroy(clnt);
961 rpc_clnt_debugfs_unregister(clnt);
962 rpc_free_clid(clnt);
963 rpc_clnt_remove_pipedir(clnt);
964 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
965
966 kfree(clnt);
967 rpciod_down();
968}
969static struct rpc_clnt *
970rpc_free_client(struct rpc_clnt *clnt)
971{
972 struct rpc_clnt *parent = NULL;
973
974 trace_rpc_clnt_release(clnt);
975 if (clnt->cl_parent != clnt)
976 parent = clnt->cl_parent;
977 rpc_unregister_client(clnt);
978 rpc_free_iostats(clnt->cl_metrics);
979 clnt->cl_metrics = NULL;
980 xprt_iter_destroy(&clnt->cl_xpi);
981 put_cred(clnt->cl_cred);
982
983 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
984 schedule_work(&clnt->cl_work);
985 return parent;
986}
987
988/*
989 * Free an RPC client
990 */
991static struct rpc_clnt *
992rpc_free_auth(struct rpc_clnt *clnt)
993{
994 /*
995 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
996 * release remaining GSS contexts. This mechanism ensures
997 * that it can do so safely.
998 */
999 if (clnt->cl_auth != NULL) {
1000 rpcauth_release(clnt->cl_auth);
1001 clnt->cl_auth = NULL;
1002 }
1003 if (refcount_dec_and_test(&clnt->cl_count))
1004 return rpc_free_client(clnt);
1005 return NULL;
1006}
1007
1008/*
1009 * Release reference to the RPC client
1010 */
1011void
1012rpc_release_client(struct rpc_clnt *clnt)
1013{
1014 do {
1015 if (list_empty(&clnt->cl_tasks))
1016 wake_up(&destroy_wait);
1017 if (refcount_dec_not_one(&clnt->cl_count))
1018 break;
1019 clnt = rpc_free_auth(clnt);
1020 } while (clnt != NULL);
1021}
1022EXPORT_SYMBOL_GPL(rpc_release_client);
1023
1024/**
1025 * rpc_bind_new_program - bind a new RPC program to an existing client
1026 * @old: old rpc_client
1027 * @program: rpc program to set
1028 * @vers: rpc program version
1029 *
1030 * Clones the rpc client and sets up a new RPC program. This is mainly
1031 * of use for enabling different RPC programs to share the same transport.
1032 * The Sun NFSv2/v3 ACL protocol can do this.
1033 */
1034struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1035 const struct rpc_program *program,
1036 u32 vers)
1037{
1038 struct rpc_create_args args = {
1039 .program = program,
1040 .prognumber = program->number,
1041 .version = vers,
1042 .authflavor = old->cl_auth->au_flavor,
1043 .cred = old->cl_cred,
1044 };
1045 struct rpc_clnt *clnt;
1046 int err;
1047
1048 clnt = __rpc_clone_client(&args, old);
1049 if (IS_ERR(clnt))
1050 goto out;
1051 err = rpc_ping(clnt);
1052 if (err != 0) {
1053 rpc_shutdown_client(clnt);
1054 clnt = ERR_PTR(err);
1055 }
1056out:
1057 return clnt;
1058}
1059EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1060
1061struct rpc_xprt *
1062rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1063{
1064 struct rpc_xprt_switch *xps;
1065
1066 if (!xprt)
1067 return NULL;
1068 rcu_read_lock();
1069 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1070 atomic_long_inc(&xps->xps_queuelen);
1071 rcu_read_unlock();
1072 atomic_long_inc(&xprt->queuelen);
1073
1074 return xprt;
1075}
1076
1077static void
1078rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1079{
1080 struct rpc_xprt_switch *xps;
1081
1082 atomic_long_dec(&xprt->queuelen);
1083 rcu_read_lock();
1084 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1085 atomic_long_dec(&xps->xps_queuelen);
1086 rcu_read_unlock();
1087
1088 xprt_put(xprt);
1089}
1090
1091void rpc_task_release_transport(struct rpc_task *task)
1092{
1093 struct rpc_xprt *xprt = task->tk_xprt;
1094
1095 if (xprt) {
1096 task->tk_xprt = NULL;
1097 if (task->tk_client)
1098 rpc_task_release_xprt(task->tk_client, xprt);
1099 else
1100 xprt_put(xprt);
1101 }
1102}
1103EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1104
1105void rpc_task_release_client(struct rpc_task *task)
1106{
1107 struct rpc_clnt *clnt = task->tk_client;
1108
1109 rpc_task_release_transport(task);
1110 if (clnt != NULL) {
1111 /* Remove from client task list */
1112 spin_lock(&clnt->cl_lock);
1113 list_del(&task->tk_task);
1114 spin_unlock(&clnt->cl_lock);
1115 task->tk_client = NULL;
1116
1117 rpc_release_client(clnt);
1118 }
1119}
1120
1121static struct rpc_xprt *
1122rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1123{
1124 struct rpc_xprt *xprt;
1125
1126 rcu_read_lock();
1127 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1128 rcu_read_unlock();
1129 return rpc_task_get_xprt(clnt, xprt);
1130}
1131
1132static struct rpc_xprt *
1133rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1134{
1135 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1136}
1137
1138static
1139void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1140{
1141 if (task->tk_xprt) {
1142 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1143 (task->tk_flags & RPC_TASK_MOVEABLE)))
1144 return;
1145 xprt_release(task);
1146 xprt_put(task->tk_xprt);
1147 }
1148 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1149 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1150 else
1151 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1152}
1153
1154static
1155void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1156{
1157 rpc_task_set_transport(task, clnt);
1158 task->tk_client = clnt;
1159 refcount_inc(&clnt->cl_count);
1160 if (clnt->cl_softrtry)
1161 task->tk_flags |= RPC_TASK_SOFT;
1162 if (clnt->cl_softerr)
1163 task->tk_flags |= RPC_TASK_TIMEOUT;
1164 if (clnt->cl_noretranstimeo)
1165 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1166 /* Add to the client's list of all tasks */
1167 spin_lock(&clnt->cl_lock);
1168 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1169 spin_unlock(&clnt->cl_lock);
1170}
1171
1172static void
1173rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1174{
1175 if (msg != NULL) {
1176 task->tk_msg.rpc_proc = msg->rpc_proc;
1177 task->tk_msg.rpc_argp = msg->rpc_argp;
1178 task->tk_msg.rpc_resp = msg->rpc_resp;
1179 task->tk_msg.rpc_cred = msg->rpc_cred;
1180 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1181 get_cred(task->tk_msg.rpc_cred);
1182 }
1183}
1184
1185/*
1186 * Default callback for async RPC calls
1187 */
1188static void
1189rpc_default_callback(struct rpc_task *task, void *data)
1190{
1191}
1192
1193static const struct rpc_call_ops rpc_default_ops = {
1194 .rpc_call_done = rpc_default_callback,
1195};
1196
1197/**
1198 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1199 * @task_setup_data: pointer to task initialisation data
1200 */
1201struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1202{
1203 struct rpc_task *task;
1204
1205 task = rpc_new_task(task_setup_data);
1206 if (IS_ERR(task))
1207 return task;
1208
1209 if (!RPC_IS_ASYNC(task))
1210 task->tk_flags |= RPC_TASK_CRED_NOREF;
1211
1212 rpc_task_set_client(task, task_setup_data->rpc_client);
1213 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1214
1215 if (task->tk_action == NULL)
1216 rpc_call_start(task);
1217
1218 atomic_inc(&task->tk_count);
1219 rpc_execute(task);
1220 return task;
1221}
1222EXPORT_SYMBOL_GPL(rpc_run_task);
1223
1224/**
1225 * rpc_call_sync - Perform a synchronous RPC call
1226 * @clnt: pointer to RPC client
1227 * @msg: RPC call parameters
1228 * @flags: RPC call flags
1229 */
1230int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1231{
1232 struct rpc_task *task;
1233 struct rpc_task_setup task_setup_data = {
1234 .rpc_client = clnt,
1235 .rpc_message = msg,
1236 .callback_ops = &rpc_default_ops,
1237 .flags = flags,
1238 };
1239 int status;
1240
1241 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1242 if (flags & RPC_TASK_ASYNC) {
1243 rpc_release_calldata(task_setup_data.callback_ops,
1244 task_setup_data.callback_data);
1245 return -EINVAL;
1246 }
1247
1248 task = rpc_run_task(&task_setup_data);
1249 if (IS_ERR(task))
1250 return PTR_ERR(task);
1251 status = task->tk_status;
1252 rpc_put_task(task);
1253 return status;
1254}
1255EXPORT_SYMBOL_GPL(rpc_call_sync);
1256
1257/**
1258 * rpc_call_async - Perform an asynchronous RPC call
1259 * @clnt: pointer to RPC client
1260 * @msg: RPC call parameters
1261 * @flags: RPC call flags
1262 * @tk_ops: RPC call ops
1263 * @data: user call data
1264 */
1265int
1266rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1267 const struct rpc_call_ops *tk_ops, void *data)
1268{
1269 struct rpc_task *task;
1270 struct rpc_task_setup task_setup_data = {
1271 .rpc_client = clnt,
1272 .rpc_message = msg,
1273 .callback_ops = tk_ops,
1274 .callback_data = data,
1275 .flags = flags|RPC_TASK_ASYNC,
1276 };
1277
1278 task = rpc_run_task(&task_setup_data);
1279 if (IS_ERR(task))
1280 return PTR_ERR(task);
1281 rpc_put_task(task);
1282 return 0;
1283}
1284EXPORT_SYMBOL_GPL(rpc_call_async);
1285
1286#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1287static void call_bc_encode(struct rpc_task *task);
1288
1289/**
1290 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1291 * rpc_execute against it
1292 * @req: RPC request
1293 */
1294struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1295{
1296 struct rpc_task *task;
1297 struct rpc_task_setup task_setup_data = {
1298 .callback_ops = &rpc_default_ops,
1299 .flags = RPC_TASK_SOFTCONN |
1300 RPC_TASK_NO_RETRANS_TIMEOUT,
1301 };
1302
1303 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1304 /*
1305 * Create an rpc_task to send the data
1306 */
1307 task = rpc_new_task(&task_setup_data);
1308 if (IS_ERR(task)) {
1309 xprt_free_bc_request(req);
1310 return task;
1311 }
1312
1313 xprt_init_bc_request(req, task);
1314
1315 task->tk_action = call_bc_encode;
1316 atomic_inc(&task->tk_count);
1317 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1318 rpc_execute(task);
1319
1320 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1321 return task;
1322}
1323#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1324
1325/**
1326 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1327 * @req: RPC request to prepare
1328 * @pages: vector of struct page pointers
1329 * @base: offset in first page where receive should start, in bytes
1330 * @len: expected size of the upper layer data payload, in bytes
1331 * @hdrsize: expected size of upper layer reply header, in XDR words
1332 *
1333 */
1334void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1335 unsigned int base, unsigned int len,
1336 unsigned int hdrsize)
1337{
1338 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1339
1340 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1341 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1342}
1343EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1344
1345void
1346rpc_call_start(struct rpc_task *task)
1347{
1348 task->tk_action = call_start;
1349}
1350EXPORT_SYMBOL_GPL(rpc_call_start);
1351
1352/**
1353 * rpc_peeraddr - extract remote peer address from clnt's xprt
1354 * @clnt: RPC client structure
1355 * @buf: target buffer
1356 * @bufsize: length of target buffer
1357 *
1358 * Returns the number of bytes that are actually in the stored address.
1359 */
1360size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1361{
1362 size_t bytes;
1363 struct rpc_xprt *xprt;
1364
1365 rcu_read_lock();
1366 xprt = rcu_dereference(clnt->cl_xprt);
1367
1368 bytes = xprt->addrlen;
1369 if (bytes > bufsize)
1370 bytes = bufsize;
1371 memcpy(buf, &xprt->addr, bytes);
1372 rcu_read_unlock();
1373
1374 return bytes;
1375}
1376EXPORT_SYMBOL_GPL(rpc_peeraddr);
1377
1378/**
1379 * rpc_peeraddr2str - return remote peer address in printable format
1380 * @clnt: RPC client structure
1381 * @format: address format
1382 *
1383 * NB: the lifetime of the memory referenced by the returned pointer is
1384 * the same as the rpc_xprt itself. As long as the caller uses this
1385 * pointer, it must hold the RCU read lock.
1386 */
1387const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1388 enum rpc_display_format_t format)
1389{
1390 struct rpc_xprt *xprt;
1391
1392 xprt = rcu_dereference(clnt->cl_xprt);
1393
1394 if (xprt->address_strings[format] != NULL)
1395 return xprt->address_strings[format];
1396 else
1397 return "unprintable";
1398}
1399EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1400
1401static const struct sockaddr_in rpc_inaddr_loopback = {
1402 .sin_family = AF_INET,
1403 .sin_addr.s_addr = htonl(INADDR_ANY),
1404};
1405
1406static const struct sockaddr_in6 rpc_in6addr_loopback = {
1407 .sin6_family = AF_INET6,
1408 .sin6_addr = IN6ADDR_ANY_INIT,
1409};
1410
1411/*
1412 * Try a getsockname() on a connected datagram socket. Using a
1413 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1414 * This conserves the ephemeral port number space.
1415 *
1416 * Returns zero and fills in "buf" if successful; otherwise, a
1417 * negative errno is returned.
1418 */
1419static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1420 struct sockaddr *buf)
1421{
1422 struct socket *sock;
1423 int err;
1424
1425 err = __sock_create(net, sap->sa_family,
1426 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1427 if (err < 0) {
1428 dprintk("RPC: can't create UDP socket (%d)\n", err);
1429 goto out;
1430 }
1431
1432 switch (sap->sa_family) {
1433 case AF_INET:
1434 err = kernel_bind(sock,
1435 (struct sockaddr *)&rpc_inaddr_loopback,
1436 sizeof(rpc_inaddr_loopback));
1437 break;
1438 case AF_INET6:
1439 err = kernel_bind(sock,
1440 (struct sockaddr *)&rpc_in6addr_loopback,
1441 sizeof(rpc_in6addr_loopback));
1442 break;
1443 default:
1444 err = -EAFNOSUPPORT;
1445 goto out_release;
1446 }
1447 if (err < 0) {
1448 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1449 goto out_release;
1450 }
1451
1452 err = kernel_connect(sock, sap, salen, 0);
1453 if (err < 0) {
1454 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1455 goto out_release;
1456 }
1457
1458 err = kernel_getsockname(sock, buf);
1459 if (err < 0) {
1460 dprintk("RPC: getsockname failed (%d)\n", err);
1461 goto out_release;
1462 }
1463
1464 err = 0;
1465 if (buf->sa_family == AF_INET6) {
1466 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1467 sin6->sin6_scope_id = 0;
1468 }
1469 dprintk("RPC: %s succeeded\n", __func__);
1470
1471out_release:
1472 sock_release(sock);
1473out:
1474 return err;
1475}
1476
1477/*
1478 * Scraping a connected socket failed, so we don't have a useable
1479 * local address. Fallback: generate an address that will prevent
1480 * the server from calling us back.
1481 *
1482 * Returns zero and fills in "buf" if successful; otherwise, a
1483 * negative errno is returned.
1484 */
1485static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1486{
1487 switch (family) {
1488 case AF_INET:
1489 if (buflen < sizeof(rpc_inaddr_loopback))
1490 return -EINVAL;
1491 memcpy(buf, &rpc_inaddr_loopback,
1492 sizeof(rpc_inaddr_loopback));
1493 break;
1494 case AF_INET6:
1495 if (buflen < sizeof(rpc_in6addr_loopback))
1496 return -EINVAL;
1497 memcpy(buf, &rpc_in6addr_loopback,
1498 sizeof(rpc_in6addr_loopback));
1499 break;
1500 default:
1501 dprintk("RPC: %s: address family not supported\n",
1502 __func__);
1503 return -EAFNOSUPPORT;
1504 }
1505 dprintk("RPC: %s: succeeded\n", __func__);
1506 return 0;
1507}
1508
1509/**
1510 * rpc_localaddr - discover local endpoint address for an RPC client
1511 * @clnt: RPC client structure
1512 * @buf: target buffer
1513 * @buflen: size of target buffer, in bytes
1514 *
1515 * Returns zero and fills in "buf" and "buflen" if successful;
1516 * otherwise, a negative errno is returned.
1517 *
1518 * This works even if the underlying transport is not currently connected,
1519 * or if the upper layer never previously provided a source address.
1520 *
1521 * The result of this function call is transient: multiple calls in
1522 * succession may give different results, depending on how local
1523 * networking configuration changes over time.
1524 */
1525int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1526{
1527 struct sockaddr_storage address;
1528 struct sockaddr *sap = (struct sockaddr *)&address;
1529 struct rpc_xprt *xprt;
1530 struct net *net;
1531 size_t salen;
1532 int err;
1533
1534 rcu_read_lock();
1535 xprt = rcu_dereference(clnt->cl_xprt);
1536 salen = xprt->addrlen;
1537 memcpy(sap, &xprt->addr, salen);
1538 net = get_net(xprt->xprt_net);
1539 rcu_read_unlock();
1540
1541 rpc_set_port(sap, 0);
1542 err = rpc_sockname(net, sap, salen, buf);
1543 put_net(net);
1544 if (err != 0)
1545 /* Couldn't discover local address, return ANYADDR */
1546 return rpc_anyaddr(sap->sa_family, buf, buflen);
1547 return 0;
1548}
1549EXPORT_SYMBOL_GPL(rpc_localaddr);
1550
1551void
1552rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1553{
1554 struct rpc_xprt *xprt;
1555
1556 rcu_read_lock();
1557 xprt = rcu_dereference(clnt->cl_xprt);
1558 if (xprt->ops->set_buffer_size)
1559 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1560 rcu_read_unlock();
1561}
1562EXPORT_SYMBOL_GPL(rpc_setbufsize);
1563
1564/**
1565 * rpc_net_ns - Get the network namespace for this RPC client
1566 * @clnt: RPC client to query
1567 *
1568 */
1569struct net *rpc_net_ns(struct rpc_clnt *clnt)
1570{
1571 struct net *ret;
1572
1573 rcu_read_lock();
1574 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1575 rcu_read_unlock();
1576 return ret;
1577}
1578EXPORT_SYMBOL_GPL(rpc_net_ns);
1579
1580/**
1581 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1582 * @clnt: RPC client to query
1583 *
1584 * For stream transports, this is one RPC record fragment (see RFC
1585 * 1831), as we don't support multi-record requests yet. For datagram
1586 * transports, this is the size of an IP packet minus the IP, UDP, and
1587 * RPC header sizes.
1588 */
1589size_t rpc_max_payload(struct rpc_clnt *clnt)
1590{
1591 size_t ret;
1592
1593 rcu_read_lock();
1594 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1595 rcu_read_unlock();
1596 return ret;
1597}
1598EXPORT_SYMBOL_GPL(rpc_max_payload);
1599
1600/**
1601 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1602 * @clnt: RPC client to query
1603 */
1604size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1605{
1606 struct rpc_xprt *xprt;
1607 size_t ret;
1608
1609 rcu_read_lock();
1610 xprt = rcu_dereference(clnt->cl_xprt);
1611 ret = xprt->ops->bc_maxpayload(xprt);
1612 rcu_read_unlock();
1613 return ret;
1614}
1615EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1616
1617unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1618{
1619 struct rpc_xprt *xprt;
1620 unsigned int ret;
1621
1622 rcu_read_lock();
1623 xprt = rcu_dereference(clnt->cl_xprt);
1624 ret = xprt->ops->bc_num_slots(xprt);
1625 rcu_read_unlock();
1626 return ret;
1627}
1628EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1629
1630/**
1631 * rpc_force_rebind - force transport to check that remote port is unchanged
1632 * @clnt: client to rebind
1633 *
1634 */
1635void rpc_force_rebind(struct rpc_clnt *clnt)
1636{
1637 if (clnt->cl_autobind) {
1638 rcu_read_lock();
1639 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1640 rcu_read_unlock();
1641 }
1642}
1643EXPORT_SYMBOL_GPL(rpc_force_rebind);
1644
1645static int
1646__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1647{
1648 task->tk_status = 0;
1649 task->tk_rpc_status = 0;
1650 task->tk_action = action;
1651 return 1;
1652}
1653
1654/*
1655 * Restart an (async) RPC call. Usually called from within the
1656 * exit handler.
1657 */
1658int
1659rpc_restart_call(struct rpc_task *task)
1660{
1661 return __rpc_restart_call(task, call_start);
1662}
1663EXPORT_SYMBOL_GPL(rpc_restart_call);
1664
1665/*
1666 * Restart an (async) RPC call from the call_prepare state.
1667 * Usually called from within the exit handler.
1668 */
1669int
1670rpc_restart_call_prepare(struct rpc_task *task)
1671{
1672 if (task->tk_ops->rpc_call_prepare != NULL)
1673 return __rpc_restart_call(task, rpc_prepare_task);
1674 return rpc_restart_call(task);
1675}
1676EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1677
1678const char
1679*rpc_proc_name(const struct rpc_task *task)
1680{
1681 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1682
1683 if (proc) {
1684 if (proc->p_name)
1685 return proc->p_name;
1686 else
1687 return "NULL";
1688 } else
1689 return "no proc";
1690}
1691
1692static void
1693__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1694{
1695 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1696 rpc_task_set_rpc_status(task, rpc_status);
1697 rpc_exit(task, tk_status);
1698}
1699
1700static void
1701rpc_call_rpcerror(struct rpc_task *task, int status)
1702{
1703 __rpc_call_rpcerror(task, status, status);
1704}
1705
1706/*
1707 * 0. Initial state
1708 *
1709 * Other FSM states can be visited zero or more times, but
1710 * this state is visited exactly once for each RPC.
1711 */
1712static void
1713call_start(struct rpc_task *task)
1714{
1715 struct rpc_clnt *clnt = task->tk_client;
1716 int idx = task->tk_msg.rpc_proc->p_statidx;
1717
1718 trace_rpc_request(task);
1719
1720 /* Increment call count (version might not be valid for ping) */
1721 if (clnt->cl_program->version[clnt->cl_vers])
1722 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1723 clnt->cl_stats->rpccnt++;
1724 task->tk_action = call_reserve;
1725 rpc_task_set_transport(task, clnt);
1726}
1727
1728/*
1729 * 1. Reserve an RPC call slot
1730 */
1731static void
1732call_reserve(struct rpc_task *task)
1733{
1734 task->tk_status = 0;
1735 task->tk_action = call_reserveresult;
1736 xprt_reserve(task);
1737}
1738
1739static void call_retry_reserve(struct rpc_task *task);
1740
1741/*
1742 * 1b. Grok the result of xprt_reserve()
1743 */
1744static void
1745call_reserveresult(struct rpc_task *task)
1746{
1747 int status = task->tk_status;
1748
1749 /*
1750 * After a call to xprt_reserve(), we must have either
1751 * a request slot or else an error status.
1752 */
1753 task->tk_status = 0;
1754 if (status >= 0) {
1755 if (task->tk_rqstp) {
1756 task->tk_action = call_refresh;
1757 return;
1758 }
1759
1760 rpc_call_rpcerror(task, -EIO);
1761 return;
1762 }
1763
1764 switch (status) {
1765 case -ENOMEM:
1766 rpc_delay(task, HZ >> 2);
1767 fallthrough;
1768 case -EAGAIN: /* woken up; retry */
1769 task->tk_action = call_retry_reserve;
1770 return;
1771 default:
1772 rpc_call_rpcerror(task, status);
1773 }
1774}
1775
1776/*
1777 * 1c. Retry reserving an RPC call slot
1778 */
1779static void
1780call_retry_reserve(struct rpc_task *task)
1781{
1782 task->tk_status = 0;
1783 task->tk_action = call_reserveresult;
1784 xprt_retry_reserve(task);
1785}
1786
1787/*
1788 * 2. Bind and/or refresh the credentials
1789 */
1790static void
1791call_refresh(struct rpc_task *task)
1792{
1793 task->tk_action = call_refreshresult;
1794 task->tk_status = 0;
1795 task->tk_client->cl_stats->rpcauthrefresh++;
1796 rpcauth_refreshcred(task);
1797}
1798
1799/*
1800 * 2a. Process the results of a credential refresh
1801 */
1802static void
1803call_refreshresult(struct rpc_task *task)
1804{
1805 int status = task->tk_status;
1806
1807 task->tk_status = 0;
1808 task->tk_action = call_refresh;
1809 switch (status) {
1810 case 0:
1811 if (rpcauth_uptodatecred(task)) {
1812 task->tk_action = call_allocate;
1813 return;
1814 }
1815 /* Use rate-limiting and a max number of retries if refresh
1816 * had status 0 but failed to update the cred.
1817 */
1818 fallthrough;
1819 case -ETIMEDOUT:
1820 rpc_delay(task, 3*HZ);
1821 fallthrough;
1822 case -EAGAIN:
1823 status = -EACCES;
1824 fallthrough;
1825 case -EKEYEXPIRED:
1826 if (!task->tk_cred_retry)
1827 break;
1828 task->tk_cred_retry--;
1829 trace_rpc_retry_refresh_status(task);
1830 return;
1831 case -ENOMEM:
1832 rpc_delay(task, HZ >> 4);
1833 return;
1834 }
1835 trace_rpc_refresh_status(task);
1836 rpc_call_rpcerror(task, status);
1837}
1838
1839/*
1840 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1841 * (Note: buffer memory is freed in xprt_release).
1842 */
1843static void
1844call_allocate(struct rpc_task *task)
1845{
1846 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1847 struct rpc_rqst *req = task->tk_rqstp;
1848 struct rpc_xprt *xprt = req->rq_xprt;
1849 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1850 int status;
1851
1852 task->tk_status = 0;
1853 task->tk_action = call_encode;
1854
1855 if (req->rq_buffer)
1856 return;
1857
1858 if (proc->p_proc != 0) {
1859 BUG_ON(proc->p_arglen == 0);
1860 if (proc->p_decode != NULL)
1861 BUG_ON(proc->p_replen == 0);
1862 }
1863
1864 /*
1865 * Calculate the size (in quads) of the RPC call
1866 * and reply headers, and convert both values
1867 * to byte sizes.
1868 */
1869 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1870 proc->p_arglen;
1871 req->rq_callsize <<= 2;
1872 /*
1873 * Note: the reply buffer must at minimum allocate enough space
1874 * for the 'struct accepted_reply' from RFC5531.
1875 */
1876 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1877 max_t(size_t, proc->p_replen, 2);
1878 req->rq_rcvsize <<= 2;
1879
1880 status = xprt->ops->buf_alloc(task);
1881 trace_rpc_buf_alloc(task, status);
1882 if (status == 0)
1883 return;
1884 if (status != -ENOMEM) {
1885 rpc_call_rpcerror(task, status);
1886 return;
1887 }
1888
1889 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1890 task->tk_action = call_allocate;
1891 rpc_delay(task, HZ>>4);
1892 return;
1893 }
1894
1895 rpc_call_rpcerror(task, -ERESTARTSYS);
1896}
1897
1898static int
1899rpc_task_need_encode(struct rpc_task *task)
1900{
1901 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1902 (!(task->tk_flags & RPC_TASK_SENT) ||
1903 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1904 xprt_request_need_retransmit(task));
1905}
1906
1907static void
1908rpc_xdr_encode(struct rpc_task *task)
1909{
1910 struct rpc_rqst *req = task->tk_rqstp;
1911 struct xdr_stream xdr;
1912
1913 xdr_buf_init(&req->rq_snd_buf,
1914 req->rq_buffer,
1915 req->rq_callsize);
1916 xdr_buf_init(&req->rq_rcv_buf,
1917 req->rq_rbuffer,
1918 req->rq_rcvsize);
1919
1920 req->rq_reply_bytes_recvd = 0;
1921 req->rq_snd_buf.head[0].iov_len = 0;
1922 xdr_init_encode(&xdr, &req->rq_snd_buf,
1923 req->rq_snd_buf.head[0].iov_base, req);
1924 if (rpc_encode_header(task, &xdr))
1925 return;
1926
1927 task->tk_status = rpcauth_wrap_req(task, &xdr);
1928}
1929
1930/*
1931 * 3. Encode arguments of an RPC call
1932 */
1933static void
1934call_encode(struct rpc_task *task)
1935{
1936 if (!rpc_task_need_encode(task))
1937 goto out;
1938
1939 /* Dequeue task from the receive queue while we're encoding */
1940 xprt_request_dequeue_xprt(task);
1941 /* Encode here so that rpcsec_gss can use correct sequence number. */
1942 rpc_xdr_encode(task);
1943 /* Add task to reply queue before transmission to avoid races */
1944 if (task->tk_status == 0 && rpc_reply_expected(task))
1945 task->tk_status = xprt_request_enqueue_receive(task);
1946 /* Did the encode result in an error condition? */
1947 if (task->tk_status != 0) {
1948 /* Was the error nonfatal? */
1949 switch (task->tk_status) {
1950 case -EAGAIN:
1951 case -ENOMEM:
1952 rpc_delay(task, HZ >> 4);
1953 break;
1954 case -EKEYEXPIRED:
1955 if (!task->tk_cred_retry) {
1956 rpc_call_rpcerror(task, task->tk_status);
1957 } else {
1958 task->tk_action = call_refresh;
1959 task->tk_cred_retry--;
1960 trace_rpc_retry_refresh_status(task);
1961 }
1962 break;
1963 default:
1964 rpc_call_rpcerror(task, task->tk_status);
1965 }
1966 return;
1967 }
1968
1969 xprt_request_enqueue_transmit(task);
1970out:
1971 task->tk_action = call_transmit;
1972 /* Check that the connection is OK */
1973 if (!xprt_bound(task->tk_xprt))
1974 task->tk_action = call_bind;
1975 else if (!xprt_connected(task->tk_xprt))
1976 task->tk_action = call_connect;
1977}
1978
1979/*
1980 * Helpers to check if the task was already transmitted, and
1981 * to take action when that is the case.
1982 */
1983static bool
1984rpc_task_transmitted(struct rpc_task *task)
1985{
1986 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1987}
1988
1989static void
1990rpc_task_handle_transmitted(struct rpc_task *task)
1991{
1992 xprt_end_transmit(task);
1993 task->tk_action = call_transmit_status;
1994}
1995
1996/*
1997 * 4. Get the server port number if not yet set
1998 */
1999static void
2000call_bind(struct rpc_task *task)
2001{
2002 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2003
2004 if (rpc_task_transmitted(task)) {
2005 rpc_task_handle_transmitted(task);
2006 return;
2007 }
2008
2009 if (xprt_bound(xprt)) {
2010 task->tk_action = call_connect;
2011 return;
2012 }
2013
2014 task->tk_action = call_bind_status;
2015 if (!xprt_prepare_transmit(task))
2016 return;
2017
2018 xprt->ops->rpcbind(task);
2019}
2020
2021/*
2022 * 4a. Sort out bind result
2023 */
2024static void
2025call_bind_status(struct rpc_task *task)
2026{
2027 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2028 int status = -EIO;
2029
2030 if (rpc_task_transmitted(task)) {
2031 rpc_task_handle_transmitted(task);
2032 return;
2033 }
2034
2035 if (task->tk_status >= 0)
2036 goto out_next;
2037 if (xprt_bound(xprt)) {
2038 task->tk_status = 0;
2039 goto out_next;
2040 }
2041
2042 switch (task->tk_status) {
2043 case -ENOMEM:
2044 rpc_delay(task, HZ >> 2);
2045 goto retry_timeout;
2046 case -EACCES:
2047 trace_rpcb_prog_unavail_err(task);
2048 /* fail immediately if this is an RPC ping */
2049 if (task->tk_msg.rpc_proc->p_proc == 0) {
2050 status = -EOPNOTSUPP;
2051 break;
2052 }
2053 if (task->tk_rebind_retry == 0)
2054 break;
2055 task->tk_rebind_retry--;
2056 rpc_delay(task, 3*HZ);
2057 goto retry_timeout;
2058 case -ENOBUFS:
2059 rpc_delay(task, HZ >> 2);
2060 goto retry_timeout;
2061 case -EAGAIN:
2062 goto retry_timeout;
2063 case -ETIMEDOUT:
2064 trace_rpcb_timeout_err(task);
2065 goto retry_timeout;
2066 case -EPFNOSUPPORT:
2067 /* server doesn't support any rpcbind version we know of */
2068 trace_rpcb_bind_version_err(task);
2069 break;
2070 case -EPROTONOSUPPORT:
2071 trace_rpcb_bind_version_err(task);
2072 goto retry_timeout;
2073 case -ECONNREFUSED: /* connection problems */
2074 case -ECONNRESET:
2075 case -ECONNABORTED:
2076 case -ENOTCONN:
2077 case -EHOSTDOWN:
2078 case -ENETDOWN:
2079 case -EHOSTUNREACH:
2080 case -ENETUNREACH:
2081 case -EPIPE:
2082 trace_rpcb_unreachable_err(task);
2083 if (!RPC_IS_SOFTCONN(task)) {
2084 rpc_delay(task, 5*HZ);
2085 goto retry_timeout;
2086 }
2087 status = task->tk_status;
2088 break;
2089 default:
2090 trace_rpcb_unrecognized_err(task);
2091 }
2092
2093 rpc_call_rpcerror(task, status);
2094 return;
2095out_next:
2096 task->tk_action = call_connect;
2097 return;
2098retry_timeout:
2099 task->tk_status = 0;
2100 task->tk_action = call_bind;
2101 rpc_check_timeout(task);
2102}
2103
2104/*
2105 * 4b. Connect to the RPC server
2106 */
2107static void
2108call_connect(struct rpc_task *task)
2109{
2110 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2111
2112 if (rpc_task_transmitted(task)) {
2113 rpc_task_handle_transmitted(task);
2114 return;
2115 }
2116
2117 if (xprt_connected(xprt)) {
2118 task->tk_action = call_transmit;
2119 return;
2120 }
2121
2122 task->tk_action = call_connect_status;
2123 if (task->tk_status < 0)
2124 return;
2125 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2126 rpc_call_rpcerror(task, -ENOTCONN);
2127 return;
2128 }
2129 if (!xprt_prepare_transmit(task))
2130 return;
2131 xprt_connect(task);
2132}
2133
2134/*
2135 * 4c. Sort out connect result
2136 */
2137static void
2138call_connect_status(struct rpc_task *task)
2139{
2140 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2141 struct rpc_clnt *clnt = task->tk_client;
2142 int status = task->tk_status;
2143
2144 if (rpc_task_transmitted(task)) {
2145 rpc_task_handle_transmitted(task);
2146 return;
2147 }
2148
2149 trace_rpc_connect_status(task);
2150
2151 if (task->tk_status == 0) {
2152 clnt->cl_stats->netreconn++;
2153 goto out_next;
2154 }
2155 if (xprt_connected(xprt)) {
2156 task->tk_status = 0;
2157 goto out_next;
2158 }
2159
2160 task->tk_status = 0;
2161 switch (status) {
2162 case -ECONNREFUSED:
2163 /* A positive refusal suggests a rebind is needed. */
2164 if (RPC_IS_SOFTCONN(task))
2165 break;
2166 if (clnt->cl_autobind) {
2167 rpc_force_rebind(clnt);
2168 goto out_retry;
2169 }
2170 fallthrough;
2171 case -ECONNRESET:
2172 case -ECONNABORTED:
2173 case -ENETDOWN:
2174 case -ENETUNREACH:
2175 case -EHOSTUNREACH:
2176 case -EPIPE:
2177 case -EPROTO:
2178 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2179 task->tk_rqstp->rq_connect_cookie);
2180 if (RPC_IS_SOFTCONN(task))
2181 break;
2182 /* retry with existing socket, after a delay */
2183 rpc_delay(task, 3*HZ);
2184 fallthrough;
2185 case -EADDRINUSE:
2186 case -ENOTCONN:
2187 case -EAGAIN:
2188 case -ETIMEDOUT:
2189 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2190 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2191 test_bit(XPRT_REMOVE, &xprt->state)) {
2192 struct rpc_xprt *saved = task->tk_xprt;
2193 struct rpc_xprt_switch *xps;
2194
2195 rcu_read_lock();
2196 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2197 rcu_read_unlock();
2198 if (xps->xps_nxprts > 1) {
2199 long value;
2200
2201 xprt_release(task);
2202 value = atomic_long_dec_return(&xprt->queuelen);
2203 if (value == 0)
2204 rpc_xprt_switch_remove_xprt(xps, saved,
2205 true);
2206 xprt_put(saved);
2207 task->tk_xprt = NULL;
2208 task->tk_action = call_start;
2209 }
2210 xprt_switch_put(xps);
2211 if (!task->tk_xprt)
2212 return;
2213 }
2214 goto out_retry;
2215 case -ENOBUFS:
2216 rpc_delay(task, HZ >> 2);
2217 goto out_retry;
2218 }
2219 rpc_call_rpcerror(task, status);
2220 return;
2221out_next:
2222 task->tk_action = call_transmit;
2223 return;
2224out_retry:
2225 /* Check for timeouts before looping back to call_bind */
2226 task->tk_action = call_bind;
2227 rpc_check_timeout(task);
2228}
2229
2230/*
2231 * 5. Transmit the RPC request, and wait for reply
2232 */
2233static void
2234call_transmit(struct rpc_task *task)
2235{
2236 if (rpc_task_transmitted(task)) {
2237 rpc_task_handle_transmitted(task);
2238 return;
2239 }
2240
2241 task->tk_action = call_transmit_status;
2242 if (!xprt_prepare_transmit(task))
2243 return;
2244 task->tk_status = 0;
2245 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2246 if (!xprt_connected(task->tk_xprt)) {
2247 task->tk_status = -ENOTCONN;
2248 return;
2249 }
2250 xprt_transmit(task);
2251 }
2252 xprt_end_transmit(task);
2253}
2254
2255/*
2256 * 5a. Handle cleanup after a transmission
2257 */
2258static void
2259call_transmit_status(struct rpc_task *task)
2260{
2261 task->tk_action = call_status;
2262
2263 /*
2264 * Common case: success. Force the compiler to put this
2265 * test first.
2266 */
2267 if (rpc_task_transmitted(task)) {
2268 task->tk_status = 0;
2269 xprt_request_wait_receive(task);
2270 return;
2271 }
2272
2273 switch (task->tk_status) {
2274 default:
2275 break;
2276 case -EBADMSG:
2277 task->tk_status = 0;
2278 task->tk_action = call_encode;
2279 break;
2280 /*
2281 * Special cases: if we've been waiting on the
2282 * socket's write_space() callback, or if the
2283 * socket just returned a connection error,
2284 * then hold onto the transport lock.
2285 */
2286 case -ENOMEM:
2287 case -ENOBUFS:
2288 rpc_delay(task, HZ>>2);
2289 fallthrough;
2290 case -EBADSLT:
2291 case -EAGAIN:
2292 task->tk_action = call_transmit;
2293 task->tk_status = 0;
2294 break;
2295 case -ECONNREFUSED:
2296 case -EHOSTDOWN:
2297 case -ENETDOWN:
2298 case -EHOSTUNREACH:
2299 case -ENETUNREACH:
2300 case -EPERM:
2301 if (RPC_IS_SOFTCONN(task)) {
2302 if (!task->tk_msg.rpc_proc->p_proc)
2303 trace_xprt_ping(task->tk_xprt,
2304 task->tk_status);
2305 rpc_call_rpcerror(task, task->tk_status);
2306 return;
2307 }
2308 fallthrough;
2309 case -ECONNRESET:
2310 case -ECONNABORTED:
2311 case -EADDRINUSE:
2312 case -ENOTCONN:
2313 case -EPIPE:
2314 task->tk_action = call_bind;
2315 task->tk_status = 0;
2316 break;
2317 }
2318 rpc_check_timeout(task);
2319}
2320
2321#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2322static void call_bc_transmit(struct rpc_task *task);
2323static void call_bc_transmit_status(struct rpc_task *task);
2324
2325static void
2326call_bc_encode(struct rpc_task *task)
2327{
2328 xprt_request_enqueue_transmit(task);
2329 task->tk_action = call_bc_transmit;
2330}
2331
2332/*
2333 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2334 * addition, disconnect on connectivity errors.
2335 */
2336static void
2337call_bc_transmit(struct rpc_task *task)
2338{
2339 task->tk_action = call_bc_transmit_status;
2340 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2341 if (!xprt_prepare_transmit(task))
2342 return;
2343 task->tk_status = 0;
2344 xprt_transmit(task);
2345 }
2346 xprt_end_transmit(task);
2347}
2348
2349static void
2350call_bc_transmit_status(struct rpc_task *task)
2351{
2352 struct rpc_rqst *req = task->tk_rqstp;
2353
2354 if (rpc_task_transmitted(task))
2355 task->tk_status = 0;
2356
2357 switch (task->tk_status) {
2358 case 0:
2359 /* Success */
2360 case -ENETDOWN:
2361 case -EHOSTDOWN:
2362 case -EHOSTUNREACH:
2363 case -ENETUNREACH:
2364 case -ECONNRESET:
2365 case -ECONNREFUSED:
2366 case -EADDRINUSE:
2367 case -ENOTCONN:
2368 case -EPIPE:
2369 break;
2370 case -ENOMEM:
2371 case -ENOBUFS:
2372 rpc_delay(task, HZ>>2);
2373 fallthrough;
2374 case -EBADSLT:
2375 case -EAGAIN:
2376 task->tk_status = 0;
2377 task->tk_action = call_bc_transmit;
2378 return;
2379 case -ETIMEDOUT:
2380 /*
2381 * Problem reaching the server. Disconnect and let the
2382 * forechannel reestablish the connection. The server will
2383 * have to retransmit the backchannel request and we'll
2384 * reprocess it. Since these ops are idempotent, there's no
2385 * need to cache our reply at this time.
2386 */
2387 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2388 "error: %d\n", task->tk_status);
2389 xprt_conditional_disconnect(req->rq_xprt,
2390 req->rq_connect_cookie);
2391 break;
2392 default:
2393 /*
2394 * We were unable to reply and will have to drop the
2395 * request. The server should reconnect and retransmit.
2396 */
2397 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2398 "error: %d\n", task->tk_status);
2399 break;
2400 }
2401 task->tk_action = rpc_exit_task;
2402}
2403#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2404
2405/*
2406 * 6. Sort out the RPC call status
2407 */
2408static void
2409call_status(struct rpc_task *task)
2410{
2411 struct rpc_clnt *clnt = task->tk_client;
2412 int status;
2413
2414 if (!task->tk_msg.rpc_proc->p_proc)
2415 trace_xprt_ping(task->tk_xprt, task->tk_status);
2416
2417 status = task->tk_status;
2418 if (status >= 0) {
2419 task->tk_action = call_decode;
2420 return;
2421 }
2422
2423 trace_rpc_call_status(task);
2424 task->tk_status = 0;
2425 switch(status) {
2426 case -EHOSTDOWN:
2427 case -ENETDOWN:
2428 case -EHOSTUNREACH:
2429 case -ENETUNREACH:
2430 case -EPERM:
2431 if (RPC_IS_SOFTCONN(task))
2432 goto out_exit;
2433 /*
2434 * Delay any retries for 3 seconds, then handle as if it
2435 * were a timeout.
2436 */
2437 rpc_delay(task, 3*HZ);
2438 fallthrough;
2439 case -ETIMEDOUT:
2440 break;
2441 case -ECONNREFUSED:
2442 case -ECONNRESET:
2443 case -ECONNABORTED:
2444 case -ENOTCONN:
2445 rpc_force_rebind(clnt);
2446 break;
2447 case -EADDRINUSE:
2448 rpc_delay(task, 3*HZ);
2449 fallthrough;
2450 case -EPIPE:
2451 case -EAGAIN:
2452 break;
2453 case -ENFILE:
2454 case -ENOBUFS:
2455 case -ENOMEM:
2456 rpc_delay(task, HZ>>2);
2457 break;
2458 case -EIO:
2459 /* shutdown or soft timeout */
2460 goto out_exit;
2461 default:
2462 if (clnt->cl_chatty)
2463 printk("%s: RPC call returned error %d\n",
2464 clnt->cl_program->name, -status);
2465 goto out_exit;
2466 }
2467 task->tk_action = call_encode;
2468 if (status != -ECONNRESET && status != -ECONNABORTED)
2469 rpc_check_timeout(task);
2470 return;
2471out_exit:
2472 rpc_call_rpcerror(task, status);
2473}
2474
2475static bool
2476rpc_check_connected(const struct rpc_rqst *req)
2477{
2478 /* No allocated request or transport? return true */
2479 if (!req || !req->rq_xprt)
2480 return true;
2481 return xprt_connected(req->rq_xprt);
2482}
2483
2484static void
2485rpc_check_timeout(struct rpc_task *task)
2486{
2487 struct rpc_clnt *clnt = task->tk_client;
2488
2489 if (RPC_SIGNALLED(task))
2490 return;
2491
2492 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2493 return;
2494
2495 trace_rpc_timeout_status(task);
2496 task->tk_timeouts++;
2497
2498 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2499 rpc_call_rpcerror(task, -ETIMEDOUT);
2500 return;
2501 }
2502
2503 if (RPC_IS_SOFT(task)) {
2504 /*
2505 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2506 * been sent, it should time out only if the transport
2507 * connection gets terminally broken.
2508 */
2509 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2510 rpc_check_connected(task->tk_rqstp))
2511 return;
2512
2513 if (clnt->cl_chatty) {
2514 pr_notice_ratelimited(
2515 "%s: server %s not responding, timed out\n",
2516 clnt->cl_program->name,
2517 task->tk_xprt->servername);
2518 }
2519 if (task->tk_flags & RPC_TASK_TIMEOUT)
2520 rpc_call_rpcerror(task, -ETIMEDOUT);
2521 else
2522 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2523 return;
2524 }
2525
2526 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2527 task->tk_flags |= RPC_CALL_MAJORSEEN;
2528 if (clnt->cl_chatty) {
2529 pr_notice_ratelimited(
2530 "%s: server %s not responding, still trying\n",
2531 clnt->cl_program->name,
2532 task->tk_xprt->servername);
2533 }
2534 }
2535 rpc_force_rebind(clnt);
2536 /*
2537 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2538 * event? RFC2203 requires the server to drop all such requests.
2539 */
2540 rpcauth_invalcred(task);
2541}
2542
2543/*
2544 * 7. Decode the RPC reply
2545 */
2546static void
2547call_decode(struct rpc_task *task)
2548{
2549 struct rpc_clnt *clnt = task->tk_client;
2550 struct rpc_rqst *req = task->tk_rqstp;
2551 struct xdr_stream xdr;
2552 int err;
2553
2554 if (!task->tk_msg.rpc_proc->p_decode) {
2555 task->tk_action = rpc_exit_task;
2556 return;
2557 }
2558
2559 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2560 if (clnt->cl_chatty) {
2561 pr_notice_ratelimited("%s: server %s OK\n",
2562 clnt->cl_program->name,
2563 task->tk_xprt->servername);
2564 }
2565 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2566 }
2567
2568 /*
2569 * Did we ever call xprt_complete_rqst()? If not, we should assume
2570 * the message is incomplete.
2571 */
2572 err = -EAGAIN;
2573 if (!req->rq_reply_bytes_recvd)
2574 goto out;
2575
2576 /* Ensure that we see all writes made by xprt_complete_rqst()
2577 * before it changed req->rq_reply_bytes_recvd.
2578 */
2579 smp_rmb();
2580
2581 req->rq_rcv_buf.len = req->rq_private_buf.len;
2582 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2583
2584 /* Check that the softirq receive buffer is valid */
2585 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2586 sizeof(req->rq_rcv_buf)) != 0);
2587
2588 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2589 req->rq_rcv_buf.head[0].iov_base, req);
2590 err = rpc_decode_header(task, &xdr);
2591out:
2592 switch (err) {
2593 case 0:
2594 task->tk_action = rpc_exit_task;
2595 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2596 return;
2597 case -EAGAIN:
2598 task->tk_status = 0;
2599 if (task->tk_client->cl_discrtry)
2600 xprt_conditional_disconnect(req->rq_xprt,
2601 req->rq_connect_cookie);
2602 task->tk_action = call_encode;
2603 rpc_check_timeout(task);
2604 break;
2605 case -EKEYREJECTED:
2606 task->tk_action = call_reserve;
2607 rpc_check_timeout(task);
2608 rpcauth_invalcred(task);
2609 /* Ensure we obtain a new XID if we retry! */
2610 xprt_release(task);
2611 }
2612}
2613
2614static int
2615rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2616{
2617 struct rpc_clnt *clnt = task->tk_client;
2618 struct rpc_rqst *req = task->tk_rqstp;
2619 __be32 *p;
2620 int error;
2621
2622 error = -EMSGSIZE;
2623 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2624 if (!p)
2625 goto out_fail;
2626 *p++ = req->rq_xid;
2627 *p++ = rpc_call;
2628 *p++ = cpu_to_be32(RPC_VERSION);
2629 *p++ = cpu_to_be32(clnt->cl_prog);
2630 *p++ = cpu_to_be32(clnt->cl_vers);
2631 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2632
2633 error = rpcauth_marshcred(task, xdr);
2634 if (error < 0)
2635 goto out_fail;
2636 return 0;
2637out_fail:
2638 trace_rpc_bad_callhdr(task);
2639 rpc_call_rpcerror(task, error);
2640 return error;
2641}
2642
2643static noinline int
2644rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2645{
2646 struct rpc_clnt *clnt = task->tk_client;
2647 int error;
2648 __be32 *p;
2649
2650 /* RFC-1014 says that the representation of XDR data must be a
2651 * multiple of four bytes
2652 * - if it isn't pointer subtraction in the NFS client may give
2653 * undefined results
2654 */
2655 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2656 goto out_unparsable;
2657
2658 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2659 if (!p)
2660 goto out_unparsable;
2661 p++; /* skip XID */
2662 if (*p++ != rpc_reply)
2663 goto out_unparsable;
2664 if (*p++ != rpc_msg_accepted)
2665 goto out_msg_denied;
2666
2667 error = rpcauth_checkverf(task, xdr);
2668 if (error)
2669 goto out_verifier;
2670
2671 p = xdr_inline_decode(xdr, sizeof(*p));
2672 if (!p)
2673 goto out_unparsable;
2674 switch (*p) {
2675 case rpc_success:
2676 return 0;
2677 case rpc_prog_unavail:
2678 trace_rpc__prog_unavail(task);
2679 error = -EPFNOSUPPORT;
2680 goto out_err;
2681 case rpc_prog_mismatch:
2682 trace_rpc__prog_mismatch(task);
2683 error = -EPROTONOSUPPORT;
2684 goto out_err;
2685 case rpc_proc_unavail:
2686 trace_rpc__proc_unavail(task);
2687 error = -EOPNOTSUPP;
2688 goto out_err;
2689 case rpc_garbage_args:
2690 case rpc_system_err:
2691 trace_rpc__garbage_args(task);
2692 error = -EIO;
2693 break;
2694 default:
2695 goto out_unparsable;
2696 }
2697
2698out_garbage:
2699 clnt->cl_stats->rpcgarbage++;
2700 if (task->tk_garb_retry) {
2701 task->tk_garb_retry--;
2702 task->tk_action = call_encode;
2703 return -EAGAIN;
2704 }
2705out_err:
2706 rpc_call_rpcerror(task, error);
2707 return error;
2708
2709out_unparsable:
2710 trace_rpc__unparsable(task);
2711 error = -EIO;
2712 goto out_garbage;
2713
2714out_verifier:
2715 trace_rpc_bad_verifier(task);
2716 goto out_err;
2717
2718out_msg_denied:
2719 error = -EACCES;
2720 p = xdr_inline_decode(xdr, sizeof(*p));
2721 if (!p)
2722 goto out_unparsable;
2723 switch (*p++) {
2724 case rpc_auth_error:
2725 break;
2726 case rpc_mismatch:
2727 trace_rpc__mismatch(task);
2728 error = -EPROTONOSUPPORT;
2729 goto out_err;
2730 default:
2731 goto out_unparsable;
2732 }
2733
2734 p = xdr_inline_decode(xdr, sizeof(*p));
2735 if (!p)
2736 goto out_unparsable;
2737 switch (*p++) {
2738 case rpc_autherr_rejectedcred:
2739 case rpc_autherr_rejectedverf:
2740 case rpcsec_gsserr_credproblem:
2741 case rpcsec_gsserr_ctxproblem:
2742 if (!task->tk_cred_retry)
2743 break;
2744 task->tk_cred_retry--;
2745 trace_rpc__stale_creds(task);
2746 return -EKEYREJECTED;
2747 case rpc_autherr_badcred:
2748 case rpc_autherr_badverf:
2749 /* possibly garbled cred/verf? */
2750 if (!task->tk_garb_retry)
2751 break;
2752 task->tk_garb_retry--;
2753 trace_rpc__bad_creds(task);
2754 task->tk_action = call_encode;
2755 return -EAGAIN;
2756 case rpc_autherr_tooweak:
2757 trace_rpc__auth_tooweak(task);
2758 pr_warn("RPC: server %s requires stronger authentication.\n",
2759 task->tk_xprt->servername);
2760 break;
2761 default:
2762 goto out_unparsable;
2763 }
2764 goto out_err;
2765}
2766
2767static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2768 const void *obj)
2769{
2770}
2771
2772static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2773 void *obj)
2774{
2775 return 0;
2776}
2777
2778static const struct rpc_procinfo rpcproc_null = {
2779 .p_encode = rpcproc_encode_null,
2780 .p_decode = rpcproc_decode_null,
2781};
2782
2783static const struct rpc_procinfo rpcproc_null_noreply = {
2784 .p_encode = rpcproc_encode_null,
2785};
2786
2787static void
2788rpc_null_call_prepare(struct rpc_task *task, void *data)
2789{
2790 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2791 rpc_call_start(task);
2792}
2793
2794static const struct rpc_call_ops rpc_null_ops = {
2795 .rpc_call_prepare = rpc_null_call_prepare,
2796 .rpc_call_done = rpc_default_callback,
2797};
2798
2799static
2800struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2801 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2802 const struct rpc_call_ops *ops, void *data)
2803{
2804 struct rpc_message msg = {
2805 .rpc_proc = &rpcproc_null,
2806 };
2807 struct rpc_task_setup task_setup_data = {
2808 .rpc_client = clnt,
2809 .rpc_xprt = xprt,
2810 .rpc_message = &msg,
2811 .rpc_op_cred = cred,
2812 .callback_ops = ops ?: &rpc_null_ops,
2813 .callback_data = data,
2814 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2815 RPC_TASK_NULLCREDS,
2816 };
2817
2818 return rpc_run_task(&task_setup_data);
2819}
2820
2821struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2822{
2823 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2824}
2825EXPORT_SYMBOL_GPL(rpc_call_null);
2826
2827static int rpc_ping(struct rpc_clnt *clnt)
2828{
2829 struct rpc_task *task;
2830 int status;
2831
2832 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2833 if (IS_ERR(task))
2834 return PTR_ERR(task);
2835 status = task->tk_status;
2836 rpc_put_task(task);
2837 return status;
2838}
2839
2840static int rpc_ping_noreply(struct rpc_clnt *clnt)
2841{
2842 struct rpc_message msg = {
2843 .rpc_proc = &rpcproc_null_noreply,
2844 };
2845 struct rpc_task_setup task_setup_data = {
2846 .rpc_client = clnt,
2847 .rpc_message = &msg,
2848 .callback_ops = &rpc_null_ops,
2849 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2850 };
2851 struct rpc_task *task;
2852 int status;
2853
2854 task = rpc_run_task(&task_setup_data);
2855 if (IS_ERR(task))
2856 return PTR_ERR(task);
2857 status = task->tk_status;
2858 rpc_put_task(task);
2859 return status;
2860}
2861
2862struct rpc_cb_add_xprt_calldata {
2863 struct rpc_xprt_switch *xps;
2864 struct rpc_xprt *xprt;
2865};
2866
2867static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2868{
2869 struct rpc_cb_add_xprt_calldata *data = calldata;
2870
2871 if (task->tk_status == 0)
2872 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2873}
2874
2875static void rpc_cb_add_xprt_release(void *calldata)
2876{
2877 struct rpc_cb_add_xprt_calldata *data = calldata;
2878
2879 xprt_put(data->xprt);
2880 xprt_switch_put(data->xps);
2881 kfree(data);
2882}
2883
2884static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2885 .rpc_call_prepare = rpc_null_call_prepare,
2886 .rpc_call_done = rpc_cb_add_xprt_done,
2887 .rpc_release = rpc_cb_add_xprt_release,
2888};
2889
2890/**
2891 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2892 * @clnt: pointer to struct rpc_clnt
2893 * @xps: pointer to struct rpc_xprt_switch,
2894 * @xprt: pointer struct rpc_xprt
2895 * @dummy: unused
2896 */
2897int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2898 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2899 void *dummy)
2900{
2901 struct rpc_cb_add_xprt_calldata *data;
2902 struct rpc_task *task;
2903
2904 if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) {
2905 rcu_read_lock();
2906 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2907 "transport to server: %s\n", clnt->cl_max_connect,
2908 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2909 rcu_read_unlock();
2910 return -EINVAL;
2911 }
2912
2913 data = kmalloc(sizeof(*data), GFP_KERNEL);
2914 if (!data)
2915 return -ENOMEM;
2916 data->xps = xprt_switch_get(xps);
2917 data->xprt = xprt_get(xprt);
2918 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2919 rpc_cb_add_xprt_release(data);
2920 goto success;
2921 }
2922
2923 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2924 &rpc_cb_add_xprt_call_ops, data);
2925 if (IS_ERR(task))
2926 return PTR_ERR(task);
2927
2928 data->xps->xps_nunique_destaddr_xprts++;
2929 rpc_put_task(task);
2930success:
2931 return 1;
2932}
2933EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2934
2935static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2936 struct rpc_xprt *xprt,
2937 struct rpc_add_xprt_test *data)
2938{
2939 struct rpc_task *task;
2940 int status = -EADDRINUSE;
2941
2942 /* Test the connection */
2943 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2944 if (IS_ERR(task))
2945 return PTR_ERR(task);
2946
2947 status = task->tk_status;
2948 rpc_put_task(task);
2949
2950 if (status < 0)
2951 return status;
2952
2953 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2954 data->add_xprt_test(clnt, xprt, data->data);
2955
2956 return 0;
2957}
2958
2959/**
2960 * rpc_clnt_setup_test_and_add_xprt()
2961 *
2962 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2963 * 1) caller of the test function must dereference the rpc_xprt_switch
2964 * and the rpc_xprt.
2965 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2966 * the rpc_call_done routine.
2967 *
2968 * Upon success (return of 1), the test function adds the new
2969 * transport to the rpc_clnt xprt switch
2970 *
2971 * @clnt: struct rpc_clnt to get the new transport
2972 * @xps: the rpc_xprt_switch to hold the new transport
2973 * @xprt: the rpc_xprt to test
2974 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2975 * and test function call data
2976 */
2977int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2978 struct rpc_xprt_switch *xps,
2979 struct rpc_xprt *xprt,
2980 void *data)
2981{
2982 int status = -EADDRINUSE;
2983
2984 xprt = xprt_get(xprt);
2985 xprt_switch_get(xps);
2986
2987 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2988 goto out_err;
2989
2990 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
2991 if (status < 0)
2992 goto out_err;
2993
2994 status = 1;
2995out_err:
2996 xprt_put(xprt);
2997 xprt_switch_put(xps);
2998 if (status < 0)
2999 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3000 "added\n", status,
3001 xprt->address_strings[RPC_DISPLAY_ADDR]);
3002 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3003 return status;
3004}
3005EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3006
3007/**
3008 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3009 * @clnt: pointer to struct rpc_clnt
3010 * @xprtargs: pointer to struct xprt_create
3011 * @setup: callback to test and/or set up the connection
3012 * @data: pointer to setup function data
3013 *
3014 * Creates a new transport using the parameters set in args and
3015 * adds it to clnt.
3016 * If ping is set, then test that connectivity succeeds before
3017 * adding the new transport.
3018 *
3019 */
3020int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3021 struct xprt_create *xprtargs,
3022 int (*setup)(struct rpc_clnt *,
3023 struct rpc_xprt_switch *,
3024 struct rpc_xprt *,
3025 void *),
3026 void *data)
3027{
3028 struct rpc_xprt_switch *xps;
3029 struct rpc_xprt *xprt;
3030 unsigned long connect_timeout;
3031 unsigned long reconnect_timeout;
3032 unsigned char resvport, reuseport;
3033 int ret = 0, ident;
3034
3035 rcu_read_lock();
3036 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3037 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3038 if (xps == NULL || xprt == NULL) {
3039 rcu_read_unlock();
3040 xprt_switch_put(xps);
3041 return -EAGAIN;
3042 }
3043 resvport = xprt->resvport;
3044 reuseport = xprt->reuseport;
3045 connect_timeout = xprt->connect_timeout;
3046 reconnect_timeout = xprt->max_reconnect_timeout;
3047 ident = xprt->xprt_class->ident;
3048 rcu_read_unlock();
3049
3050 if (!xprtargs->ident)
3051 xprtargs->ident = ident;
3052 xprt = xprt_create_transport(xprtargs);
3053 if (IS_ERR(xprt)) {
3054 ret = PTR_ERR(xprt);
3055 goto out_put_switch;
3056 }
3057 xprt->resvport = resvport;
3058 xprt->reuseport = reuseport;
3059 if (xprt->ops->set_connect_timeout != NULL)
3060 xprt->ops->set_connect_timeout(xprt,
3061 connect_timeout,
3062 reconnect_timeout);
3063
3064 rpc_xprt_switch_set_roundrobin(xps);
3065 if (setup) {
3066 ret = setup(clnt, xps, xprt, data);
3067 if (ret != 0)
3068 goto out_put_xprt;
3069 }
3070 rpc_xprt_switch_add_xprt(xps, xprt);
3071out_put_xprt:
3072 xprt_put(xprt);
3073out_put_switch:
3074 xprt_switch_put(xps);
3075 return ret;
3076}
3077EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3078
3079static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3080 struct rpc_xprt *xprt,
3081 struct rpc_add_xprt_test *data)
3082{
3083 struct rpc_xprt_switch *xps;
3084 struct rpc_xprt *main_xprt;
3085 int status = 0;
3086
3087 xprt_get(xprt);
3088
3089 rcu_read_lock();
3090 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3091 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3092 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3093 (struct sockaddr *)&main_xprt->addr);
3094 rcu_read_unlock();
3095 xprt_put(main_xprt);
3096 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3097 goto out;
3098
3099 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3100out:
3101 xprt_put(xprt);
3102 xprt_switch_put(xps);
3103 return status;
3104}
3105
3106/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3107 * @clnt rpc_clnt structure
3108 *
3109 * For each offlined transport found in the rpc_clnt structure call
3110 * the function rpc_xprt_probe_trunked() which will determine if this
3111 * transport still belongs to the trunking group.
3112 */
3113void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3114 struct rpc_add_xprt_test *data)
3115{
3116 struct rpc_xprt_iter xpi;
3117 int ret;
3118
3119 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3120 if (ret)
3121 return;
3122 for (;;) {
3123 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3124
3125 if (!xprt)
3126 break;
3127 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3128 xprt_put(xprt);
3129 if (ret < 0)
3130 break;
3131 xprt_iter_rewind(&xpi);
3132 }
3133 xprt_iter_destroy(&xpi);
3134}
3135EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3136
3137static int rpc_xprt_offline(struct rpc_clnt *clnt,
3138 struct rpc_xprt *xprt,
3139 void *data)
3140{
3141 struct rpc_xprt *main_xprt;
3142 struct rpc_xprt_switch *xps;
3143 int err = 0;
3144
3145 xprt_get(xprt);
3146
3147 rcu_read_lock();
3148 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3149 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3150 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3151 (struct sockaddr *)&main_xprt->addr);
3152 rcu_read_unlock();
3153 xprt_put(main_xprt);
3154 if (err)
3155 goto out;
3156
3157 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3158 err = -EINTR;
3159 goto out;
3160 }
3161 xprt_set_offline_locked(xprt, xps);
3162
3163 xprt_release_write(xprt, NULL);
3164out:
3165 xprt_put(xprt);
3166 xprt_switch_put(xps);
3167 return err;
3168}
3169
3170/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3171 * @clnt rpc_clnt structure
3172 *
3173 * For each active transport found in the rpc_clnt structure call
3174 * the function rpc_xprt_offline() which will identify trunked transports
3175 * and will mark them offline.
3176 */
3177void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3178{
3179 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3180}
3181EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3182
3183struct connect_timeout_data {
3184 unsigned long connect_timeout;
3185 unsigned long reconnect_timeout;
3186};
3187
3188static int
3189rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3190 struct rpc_xprt *xprt,
3191 void *data)
3192{
3193 struct connect_timeout_data *timeo = data;
3194
3195 if (xprt->ops->set_connect_timeout)
3196 xprt->ops->set_connect_timeout(xprt,
3197 timeo->connect_timeout,
3198 timeo->reconnect_timeout);
3199 return 0;
3200}
3201
3202void
3203rpc_set_connect_timeout(struct rpc_clnt *clnt,
3204 unsigned long connect_timeout,
3205 unsigned long reconnect_timeout)
3206{
3207 struct connect_timeout_data timeout = {
3208 .connect_timeout = connect_timeout,
3209 .reconnect_timeout = reconnect_timeout,
3210 };
3211 rpc_clnt_iterate_for_each_xprt(clnt,
3212 rpc_xprt_set_connect_timeout,
3213 &timeout);
3214}
3215EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3216
3217void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
3218{
3219 rcu_read_lock();
3220 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3221 rcu_read_unlock();
3222}
3223EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
3224
3225void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3226{
3227 struct rpc_xprt_switch *xps;
3228
3229 rcu_read_lock();
3230 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3231 rcu_read_unlock();
3232 xprt_set_online_locked(xprt, xps);
3233}
3234
3235void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3236{
3237 if (rpc_clnt_xprt_switch_has_addr(clnt,
3238 (const struct sockaddr *)&xprt->addr)) {
3239 return rpc_clnt_xprt_set_online(clnt, xprt);
3240 }
3241 rcu_read_lock();
3242 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3243 xprt);
3244 rcu_read_unlock();
3245}
3246EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3247
3248void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3249{
3250 struct rpc_xprt_switch *xps;
3251
3252 rcu_read_lock();
3253 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3254 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3255 xprt, 0);
3256 xps->xps_nunique_destaddr_xprts--;
3257 rcu_read_unlock();
3258}
3259EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3260
3261bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3262 const struct sockaddr *sap)
3263{
3264 struct rpc_xprt_switch *xps;
3265 bool ret;
3266
3267 rcu_read_lock();
3268 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3269 ret = rpc_xprt_switch_has_addr(xps, sap);
3270 rcu_read_unlock();
3271 return ret;
3272}
3273EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3274
3275#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3276static void rpc_show_header(void)
3277{
3278 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3279 "-timeout ---ops--\n");
3280}
3281
3282static void rpc_show_task(const struct rpc_clnt *clnt,
3283 const struct rpc_task *task)
3284{
3285 const char *rpc_waitq = "none";
3286
3287 if (RPC_IS_QUEUED(task))
3288 rpc_waitq = rpc_qname(task->tk_waitqueue);
3289
3290 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3291 task->tk_pid, task->tk_flags, task->tk_status,
3292 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3293 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3294 task->tk_action, rpc_waitq);
3295}
3296
3297void rpc_show_tasks(struct net *net)
3298{
3299 struct rpc_clnt *clnt;
3300 struct rpc_task *task;
3301 int header = 0;
3302 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3303
3304 spin_lock(&sn->rpc_client_lock);
3305 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3306 spin_lock(&clnt->cl_lock);
3307 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3308 if (!header) {
3309 rpc_show_header();
3310 header++;
3311 }
3312 rpc_show_task(clnt, task);
3313 }
3314 spin_unlock(&clnt->cl_lock);
3315 }
3316 spin_unlock(&sn->rpc_client_lock);
3317}
3318#endif
3319
3320#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3321static int
3322rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3323 struct rpc_xprt *xprt,
3324 void *dummy)
3325{
3326 return xprt_enable_swap(xprt);
3327}
3328
3329int
3330rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3331{
3332 while (clnt != clnt->cl_parent)
3333 clnt = clnt->cl_parent;
3334 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3335 return rpc_clnt_iterate_for_each_xprt(clnt,
3336 rpc_clnt_swap_activate_callback, NULL);
3337 return 0;
3338}
3339EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3340
3341static int
3342rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3343 struct rpc_xprt *xprt,
3344 void *dummy)
3345{
3346 xprt_disable_swap(xprt);
3347 return 0;
3348}
3349
3350void
3351rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3352{
3353 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3354 rpc_clnt_iterate_for_each_xprt(clnt,
3355 rpc_clnt_swap_deactivate_callback, NULL);
3356}
3357EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3358#endif /* CONFIG_SUNRPC_SWAP */