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Merge tag 'mm-hotfixes-stable-2025-07-11-16-16' of git://git.kernel.org/pub/scm/linux...
[linux-block.git] / net / sunrpc / clnt.c
... / ...
CommitLineData
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
51static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
52
53static void call_start(struct rpc_task *task);
54static void call_reserve(struct rpc_task *task);
55static void call_reserveresult(struct rpc_task *task);
56static void call_allocate(struct rpc_task *task);
57static void call_encode(struct rpc_task *task);
58static void call_decode(struct rpc_task *task);
59static void call_bind(struct rpc_task *task);
60static void call_bind_status(struct rpc_task *task);
61static void call_transmit(struct rpc_task *task);
62static void call_status(struct rpc_task *task);
63static void call_transmit_status(struct rpc_task *task);
64static void call_refresh(struct rpc_task *task);
65static void call_refreshresult(struct rpc_task *task);
66static void call_connect(struct rpc_task *task);
67static void call_connect_status(struct rpc_task *task);
68
69static int rpc_encode_header(struct rpc_task *task,
70 struct xdr_stream *xdr);
71static int rpc_decode_header(struct rpc_task *task,
72 struct xdr_stream *xdr);
73static int rpc_ping(struct rpc_clnt *clnt);
74static int rpc_ping_noreply(struct rpc_clnt *clnt);
75static void rpc_check_timeout(struct rpc_task *task);
76
77static void rpc_register_client(struct rpc_clnt *clnt)
78{
79 struct net *net = rpc_net_ns(clnt);
80 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
81
82 spin_lock(&sn->rpc_client_lock);
83 list_add(&clnt->cl_clients, &sn->all_clients);
84 spin_unlock(&sn->rpc_client_lock);
85}
86
87static void rpc_unregister_client(struct rpc_clnt *clnt)
88{
89 struct net *net = rpc_net_ns(clnt);
90 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
91
92 spin_lock(&sn->rpc_client_lock);
93 list_del(&clnt->cl_clients);
94 spin_unlock(&sn->rpc_client_lock);
95}
96
97static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
98{
99 rpc_remove_client_dir(clnt);
100}
101
102static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103{
104 struct net *net = rpc_net_ns(clnt);
105 struct super_block *pipefs_sb;
106
107 pipefs_sb = rpc_get_sb_net(net);
108 if (pipefs_sb) {
109 if (pipefs_sb == clnt->pipefs_sb)
110 __rpc_clnt_remove_pipedir(clnt);
111 rpc_put_sb_net(net);
112 }
113}
114
115static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
116 struct rpc_clnt *clnt)
117{
118 static uint32_t clntid;
119 const char *dir_name = clnt->cl_program->pipe_dir_name;
120 char name[15];
121 struct dentry *dir, *dentry;
122
123 dir = rpc_d_lookup_sb(sb, dir_name);
124 if (dir == NULL) {
125 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
126 return dir;
127 }
128 for (;;) {
129 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
130 name[sizeof(name) - 1] = '\0';
131 dentry = rpc_create_client_dir(dir, name, clnt);
132 if (!IS_ERR(dentry))
133 break;
134 if (dentry == ERR_PTR(-EEXIST))
135 continue;
136 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
137 " %s/%s, error %ld\n",
138 dir_name, name, PTR_ERR(dentry));
139 break;
140 }
141 dput(dir);
142 return dentry;
143}
144
145static int
146rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
147{
148 struct dentry *dentry;
149
150 clnt->pipefs_sb = pipefs_sb;
151
152 if (clnt->cl_program->pipe_dir_name != NULL) {
153 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
154 if (IS_ERR(dentry))
155 return PTR_ERR(dentry);
156 }
157 return 0;
158}
159
160static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
161{
162 if (clnt->cl_program->pipe_dir_name == NULL)
163 return 1;
164
165 switch (event) {
166 case RPC_PIPEFS_MOUNT:
167 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
168 return 1;
169 if (refcount_read(&clnt->cl_count) == 0)
170 return 1;
171 break;
172 case RPC_PIPEFS_UMOUNT:
173 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
174 return 1;
175 break;
176 }
177 return 0;
178}
179
180static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
181 struct super_block *sb)
182{
183 struct dentry *dentry;
184
185 switch (event) {
186 case RPC_PIPEFS_MOUNT:
187 dentry = rpc_setup_pipedir_sb(sb, clnt);
188 if (!dentry)
189 return -ENOENT;
190 if (IS_ERR(dentry))
191 return PTR_ERR(dentry);
192 break;
193 case RPC_PIPEFS_UMOUNT:
194 __rpc_clnt_remove_pipedir(clnt);
195 break;
196 default:
197 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
198 return -ENOTSUPP;
199 }
200 return 0;
201}
202
203static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
204 struct super_block *sb)
205{
206 int error = 0;
207
208 for (;; clnt = clnt->cl_parent) {
209 if (!rpc_clnt_skip_event(clnt, event))
210 error = __rpc_clnt_handle_event(clnt, event, sb);
211 if (error || clnt == clnt->cl_parent)
212 break;
213 }
214 return error;
215}
216
217static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
218{
219 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
220 struct rpc_clnt *clnt;
221
222 spin_lock(&sn->rpc_client_lock);
223 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
224 if (rpc_clnt_skip_event(clnt, event))
225 continue;
226 spin_unlock(&sn->rpc_client_lock);
227 return clnt;
228 }
229 spin_unlock(&sn->rpc_client_lock);
230 return NULL;
231}
232
233static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
234 void *ptr)
235{
236 struct super_block *sb = ptr;
237 struct rpc_clnt *clnt;
238 int error = 0;
239
240 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
241 error = __rpc_pipefs_event(clnt, event, sb);
242 if (error)
243 break;
244 }
245 return error;
246}
247
248static struct notifier_block rpc_clients_block = {
249 .notifier_call = rpc_pipefs_event,
250 .priority = SUNRPC_PIPEFS_RPC_PRIO,
251};
252
253int rpc_clients_notifier_register(void)
254{
255 return rpc_pipefs_notifier_register(&rpc_clients_block);
256}
257
258void rpc_clients_notifier_unregister(void)
259{
260 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
261}
262
263static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
264 struct rpc_xprt *xprt,
265 const struct rpc_timeout *timeout)
266{
267 struct rpc_xprt *old;
268
269 spin_lock(&clnt->cl_lock);
270 old = rcu_dereference_protected(clnt->cl_xprt,
271 lockdep_is_held(&clnt->cl_lock));
272
273 clnt->cl_timeout = timeout;
274 rcu_assign_pointer(clnt->cl_xprt, xprt);
275 spin_unlock(&clnt->cl_lock);
276
277 return old;
278}
279
280static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
281{
282 ssize_t copied;
283
284 copied = strscpy(clnt->cl_nodename,
285 nodename, sizeof(clnt->cl_nodename));
286
287 clnt->cl_nodelen = copied < 0
288 ? sizeof(clnt->cl_nodename) - 1
289 : copied;
290}
291
292static int rpc_client_register(struct rpc_clnt *clnt,
293 rpc_authflavor_t pseudoflavor,
294 const char *client_name)
295{
296 struct rpc_auth_create_args auth_args = {
297 .pseudoflavor = pseudoflavor,
298 .target_name = client_name,
299 };
300 struct rpc_auth *auth;
301 struct net *net = rpc_net_ns(clnt);
302 struct super_block *pipefs_sb;
303 int err;
304
305 rpc_clnt_debugfs_register(clnt);
306
307 pipefs_sb = rpc_get_sb_net(net);
308 if (pipefs_sb) {
309 err = rpc_setup_pipedir(pipefs_sb, clnt);
310 if (err)
311 goto out;
312 }
313
314 rpc_register_client(clnt);
315 if (pipefs_sb)
316 rpc_put_sb_net(net);
317
318 auth = rpcauth_create(&auth_args, clnt);
319 if (IS_ERR(auth)) {
320 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
321 pseudoflavor);
322 err = PTR_ERR(auth);
323 goto err_auth;
324 }
325 return 0;
326err_auth:
327 pipefs_sb = rpc_get_sb_net(net);
328 rpc_unregister_client(clnt);
329 __rpc_clnt_remove_pipedir(clnt);
330out:
331 if (pipefs_sb)
332 rpc_put_sb_net(net);
333 rpc_sysfs_client_destroy(clnt);
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_alloc(&rpc_clids, 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_free(&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 clnt->cl_xprtsec = args->xprtsec;
390
391 err = rpc_alloc_clid(clnt);
392 if (err)
393 goto out_no_clid;
394
395 clnt->cl_cred = get_cred(args->cred);
396 clnt->cl_procinfo = version->procs;
397 clnt->cl_maxproc = version->nrprocs;
398 clnt->cl_prog = args->prognumber ? : program->number;
399 clnt->cl_vers = version->number;
400 clnt->cl_stats = args->stats ? : program->stats;
401 clnt->cl_metrics = rpc_alloc_iostats(clnt);
402 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
403 err = -ENOMEM;
404 if (clnt->cl_metrics == NULL)
405 goto out_no_stats;
406 clnt->cl_program = program;
407 INIT_LIST_HEAD(&clnt->cl_tasks);
408 spin_lock_init(&clnt->cl_lock);
409
410 timeout = xprt->timeout;
411 if (args->timeout != NULL) {
412 memcpy(&clnt->cl_timeout_default, args->timeout,
413 sizeof(clnt->cl_timeout_default));
414 timeout = &clnt->cl_timeout_default;
415 }
416
417 rpc_clnt_set_transport(clnt, xprt, timeout);
418 xprt->main = true;
419 xprt_iter_init(&clnt->cl_xpi, xps);
420 xprt_switch_put(xps);
421
422 clnt->cl_rtt = &clnt->cl_rtt_default;
423 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
424
425 refcount_set(&clnt->cl_count, 1);
426
427 if (nodename == NULL)
428 nodename = utsname()->nodename;
429 /* save the nodename */
430 rpc_clnt_set_nodename(clnt, nodename);
431
432 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
433 err = rpc_client_register(clnt, args->authflavor, args->client_name);
434 if (err)
435 goto out_no_path;
436 if (parent)
437 refcount_inc(&parent->cl_count);
438
439 trace_rpc_clnt_new(clnt, xprt, args);
440 return clnt;
441
442out_no_path:
443 rpc_free_iostats(clnt->cl_metrics);
444out_no_stats:
445 put_cred(clnt->cl_cred);
446 rpc_free_clid(clnt);
447out_no_clid:
448 kfree(clnt);
449out_err:
450 rpciod_down();
451out_no_rpciod:
452 xprt_switch_put(xps);
453 xprt_put(xprt);
454 trace_rpc_clnt_new_err(program->name, args->servername, err);
455 return ERR_PTR(err);
456}
457
458static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
459 struct rpc_xprt *xprt)
460{
461 struct rpc_clnt *clnt = NULL;
462 struct rpc_xprt_switch *xps;
463
464 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
465 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
466 xps = args->bc_xprt->xpt_bc_xps;
467 xprt_switch_get(xps);
468 } else {
469 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
470 if (xps == NULL) {
471 xprt_put(xprt);
472 return ERR_PTR(-ENOMEM);
473 }
474 if (xprt->bc_xprt) {
475 xprt_switch_get(xps);
476 xprt->bc_xprt->xpt_bc_xps = xps;
477 }
478 }
479 clnt = rpc_new_client(args, xps, xprt, NULL);
480 if (IS_ERR(clnt))
481 return clnt;
482
483 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
484 int err = rpc_ping(clnt);
485 if (err != 0) {
486 rpc_shutdown_client(clnt);
487 return ERR_PTR(err);
488 }
489 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
490 int err = rpc_ping_noreply(clnt);
491 if (err != 0) {
492 rpc_shutdown_client(clnt);
493 return ERR_PTR(err);
494 }
495 }
496
497 clnt->cl_softrtry = 1;
498 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
499 clnt->cl_softrtry = 0;
500 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
501 clnt->cl_softerr = 1;
502 }
503
504 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
505 clnt->cl_autobind = 1;
506 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
507 clnt->cl_noretranstimeo = 1;
508 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
509 clnt->cl_discrtry = 1;
510 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
511 clnt->cl_chatty = 1;
512 if (args->flags & RPC_CLNT_CREATE_NETUNREACH_FATAL)
513 clnt->cl_netunreach_fatal = 1;
514
515 return clnt;
516}
517
518/**
519 * rpc_create - create an RPC client and transport with one call
520 * @args: rpc_clnt create argument structure
521 *
522 * Creates and initializes an RPC transport and an RPC client.
523 *
524 * It can ping the server in order to determine if it is up, and to see if
525 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
526 * this behavior so asynchronous tasks can also use rpc_create.
527 */
528struct rpc_clnt *rpc_create(struct rpc_create_args *args)
529{
530 struct rpc_xprt *xprt;
531 struct xprt_create xprtargs = {
532 .net = args->net,
533 .ident = args->protocol,
534 .srcaddr = args->saddress,
535 .dstaddr = args->address,
536 .addrlen = args->addrsize,
537 .servername = args->servername,
538 .bc_xprt = args->bc_xprt,
539 .xprtsec = args->xprtsec,
540 .connect_timeout = args->connect_timeout,
541 .reconnect_timeout = args->reconnect_timeout,
542 };
543 char servername[RPC_MAXNETNAMELEN];
544 struct rpc_clnt *clnt;
545 int i;
546
547 if (args->bc_xprt) {
548 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
549 xprt = args->bc_xprt->xpt_bc_xprt;
550 if (xprt) {
551 xprt_get(xprt);
552 return rpc_create_xprt(args, xprt);
553 }
554 }
555
556 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
557 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
558 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
559 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
560 /*
561 * If the caller chooses not to specify a hostname, whip
562 * up a string representation of the passed-in address.
563 */
564 if (xprtargs.servername == NULL) {
565 struct sockaddr_un *sun =
566 (struct sockaddr_un *)args->address;
567 struct sockaddr_in *sin =
568 (struct sockaddr_in *)args->address;
569 struct sockaddr_in6 *sin6 =
570 (struct sockaddr_in6 *)args->address;
571
572 servername[0] = '\0';
573 switch (args->address->sa_family) {
574 case AF_LOCAL:
575 if (sun->sun_path[0])
576 snprintf(servername, sizeof(servername), "%s",
577 sun->sun_path);
578 else
579 snprintf(servername, sizeof(servername), "@%s",
580 sun->sun_path+1);
581 break;
582 case AF_INET:
583 snprintf(servername, sizeof(servername), "%pI4",
584 &sin->sin_addr.s_addr);
585 break;
586 case AF_INET6:
587 snprintf(servername, sizeof(servername), "%pI6",
588 &sin6->sin6_addr);
589 break;
590 default:
591 /* caller wants default server name, but
592 * address family isn't recognized. */
593 return ERR_PTR(-EINVAL);
594 }
595 xprtargs.servername = servername;
596 }
597
598 xprt = xprt_create_transport(&xprtargs);
599 if (IS_ERR(xprt))
600 return (struct rpc_clnt *)xprt;
601
602 /*
603 * By default, kernel RPC client connects from a reserved port.
604 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
605 * but it is always enabled for rpciod, which handles the connect
606 * operation.
607 */
608 xprt->resvport = 1;
609 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
610 xprt->resvport = 0;
611 xprt->reuseport = 0;
612 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
613 xprt->reuseport = 1;
614
615 clnt = rpc_create_xprt(args, xprt);
616 if (IS_ERR(clnt) || args->nconnect <= 1)
617 return clnt;
618
619 for (i = 0; i < args->nconnect - 1; i++) {
620 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
621 break;
622 }
623 return clnt;
624}
625EXPORT_SYMBOL_GPL(rpc_create);
626
627/*
628 * This function clones the RPC client structure. It allows us to share the
629 * same transport while varying parameters such as the authentication
630 * flavour.
631 */
632static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
633 struct rpc_clnt *clnt)
634{
635 struct rpc_xprt_switch *xps;
636 struct rpc_xprt *xprt;
637 struct rpc_clnt *new;
638 int err;
639
640 err = -ENOMEM;
641 rcu_read_lock();
642 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
643 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
644 rcu_read_unlock();
645 if (xprt == NULL || xps == NULL) {
646 xprt_put(xprt);
647 xprt_switch_put(xps);
648 goto out_err;
649 }
650 args->servername = xprt->servername;
651 args->nodename = clnt->cl_nodename;
652
653 new = rpc_new_client(args, xps, xprt, clnt);
654 if (IS_ERR(new))
655 return new;
656
657 /* Turn off autobind on clones */
658 new->cl_autobind = 0;
659 new->cl_softrtry = clnt->cl_softrtry;
660 new->cl_softerr = clnt->cl_softerr;
661 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
662 new->cl_discrtry = clnt->cl_discrtry;
663 new->cl_chatty = clnt->cl_chatty;
664 new->cl_netunreach_fatal = clnt->cl_netunreach_fatal;
665 new->cl_principal = clnt->cl_principal;
666 new->cl_max_connect = clnt->cl_max_connect;
667 return new;
668
669out_err:
670 trace_rpc_clnt_clone_err(clnt, err);
671 return ERR_PTR(err);
672}
673
674/**
675 * rpc_clone_client - Clone an RPC client structure
676 *
677 * @clnt: RPC client whose parameters are copied
678 *
679 * Returns a fresh RPC client or an ERR_PTR.
680 */
681struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
682{
683 struct rpc_create_args args = {
684 .program = clnt->cl_program,
685 .prognumber = clnt->cl_prog,
686 .version = clnt->cl_vers,
687 .authflavor = clnt->cl_auth->au_flavor,
688 .cred = clnt->cl_cred,
689 .stats = clnt->cl_stats,
690 };
691 return __rpc_clone_client(&args, clnt);
692}
693EXPORT_SYMBOL_GPL(rpc_clone_client);
694
695/**
696 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
697 *
698 * @clnt: RPC client whose parameters are copied
699 * @flavor: security flavor for new client
700 *
701 * Returns a fresh RPC client or an ERR_PTR.
702 */
703struct rpc_clnt *
704rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
705{
706 struct rpc_create_args args = {
707 .program = clnt->cl_program,
708 .prognumber = clnt->cl_prog,
709 .version = clnt->cl_vers,
710 .authflavor = flavor,
711 .cred = clnt->cl_cred,
712 .stats = clnt->cl_stats,
713 };
714 return __rpc_clone_client(&args, clnt);
715}
716EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
717
718/**
719 * rpc_switch_client_transport: switch the RPC transport on the fly
720 * @clnt: pointer to a struct rpc_clnt
721 * @args: pointer to the new transport arguments
722 * @timeout: pointer to the new timeout parameters
723 *
724 * This function allows the caller to switch the RPC transport for the
725 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
726 * server, for instance. It assumes that the caller has ensured that
727 * there are no active RPC tasks by using some form of locking.
728 *
729 * Returns zero if "clnt" is now using the new xprt. Otherwise a
730 * negative errno is returned, and "clnt" continues to use the old
731 * xprt.
732 */
733int rpc_switch_client_transport(struct rpc_clnt *clnt,
734 struct xprt_create *args,
735 const struct rpc_timeout *timeout)
736{
737 const struct rpc_timeout *old_timeo;
738 rpc_authflavor_t pseudoflavor;
739 struct rpc_xprt_switch *xps, *oldxps;
740 struct rpc_xprt *xprt, *old;
741 struct rpc_clnt *parent;
742 int err;
743
744 args->xprtsec = clnt->cl_xprtsec;
745 xprt = xprt_create_transport(args);
746 if (IS_ERR(xprt))
747 return PTR_ERR(xprt);
748
749 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
750 if (xps == NULL) {
751 xprt_put(xprt);
752 return -ENOMEM;
753 }
754
755 pseudoflavor = clnt->cl_auth->au_flavor;
756
757 old_timeo = clnt->cl_timeout;
758 old = rpc_clnt_set_transport(clnt, xprt, timeout);
759 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
760
761 rpc_unregister_client(clnt);
762 __rpc_clnt_remove_pipedir(clnt);
763 rpc_sysfs_client_destroy(clnt);
764 rpc_clnt_debugfs_unregister(clnt);
765
766 /*
767 * A new transport was created. "clnt" therefore
768 * becomes the root of a new cl_parent tree. clnt's
769 * children, if it has any, still point to the old xprt.
770 */
771 parent = clnt->cl_parent;
772 clnt->cl_parent = clnt;
773
774 /*
775 * The old rpc_auth cache cannot be re-used. GSS
776 * contexts in particular are between a single
777 * client and server.
778 */
779 err = rpc_client_register(clnt, pseudoflavor, NULL);
780 if (err)
781 goto out_revert;
782
783 synchronize_rcu();
784 if (parent != clnt)
785 rpc_release_client(parent);
786 xprt_switch_put(oldxps);
787 xprt_put(old);
788 trace_rpc_clnt_replace_xprt(clnt);
789 return 0;
790
791out_revert:
792 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
793 rpc_clnt_set_transport(clnt, old, old_timeo);
794 clnt->cl_parent = parent;
795 rpc_client_register(clnt, pseudoflavor, NULL);
796 xprt_switch_put(xps);
797 xprt_put(xprt);
798 trace_rpc_clnt_replace_xprt_err(clnt);
799 return err;
800}
801EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
802
803static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt)
804{
805 struct rpc_xprt_switch *xps;
806
807 rcu_read_lock();
808 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
809 rcu_read_unlock();
810
811 return xps;
812}
813
814static
815int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
816 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
817{
818 struct rpc_xprt_switch *xps;
819
820 xps = rpc_clnt_xprt_switch_get(clnt);
821 if (xps == NULL)
822 return -EAGAIN;
823 func(xpi, xps);
824 xprt_switch_put(xps);
825 return 0;
826}
827
828static
829int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
830{
831 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
832}
833
834static
835int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
836 struct rpc_xprt_iter *xpi)
837{
838 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
839}
840
841/**
842 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
843 * @clnt: pointer to client
844 * @fn: function to apply
845 * @data: void pointer to function data
846 *
847 * Iterates through the list of RPC transports currently attached to the
848 * client and applies the function fn(clnt, xprt, data).
849 *
850 * On error, the iteration stops, and the function returns the error value.
851 */
852int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
853 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
854 void *data)
855{
856 struct rpc_xprt_iter xpi;
857 int ret;
858
859 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
860 if (ret)
861 return ret;
862 for (;;) {
863 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
864
865 if (!xprt)
866 break;
867 ret = fn(clnt, xprt, data);
868 xprt_put(xprt);
869 if (ret < 0)
870 break;
871 }
872 xprt_iter_destroy(&xpi);
873 return ret;
874}
875EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
876
877/*
878 * Kill all tasks for the given client.
879 * XXX: kill their descendants as well?
880 */
881void rpc_killall_tasks(struct rpc_clnt *clnt)
882{
883 struct rpc_task *rovr;
884
885
886 if (list_empty(&clnt->cl_tasks))
887 return;
888
889 /*
890 * Spin lock all_tasks to prevent changes...
891 */
892 trace_rpc_clnt_killall(clnt);
893 spin_lock(&clnt->cl_lock);
894 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
895 rpc_signal_task(rovr);
896 spin_unlock(&clnt->cl_lock);
897}
898EXPORT_SYMBOL_GPL(rpc_killall_tasks);
899
900/**
901 * rpc_cancel_tasks - try to cancel a set of RPC tasks
902 * @clnt: Pointer to RPC client
903 * @error: RPC task error value to set
904 * @fnmatch: Pointer to selector function
905 * @data: User data
906 *
907 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
908 * The argument @error must be a negative error value.
909 */
910unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
911 bool (*fnmatch)(const struct rpc_task *,
912 const void *),
913 const void *data)
914{
915 struct rpc_task *task;
916 unsigned long count = 0;
917
918 if (list_empty(&clnt->cl_tasks))
919 return 0;
920 /*
921 * Spin lock all_tasks to prevent changes...
922 */
923 spin_lock(&clnt->cl_lock);
924 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
925 if (!RPC_IS_ACTIVATED(task))
926 continue;
927 if (!fnmatch(task, data))
928 continue;
929 rpc_task_try_cancel(task, error);
930 count++;
931 }
932 spin_unlock(&clnt->cl_lock);
933 return count;
934}
935EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
936
937static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
938 struct rpc_xprt *xprt, void *dummy)
939{
940 if (xprt_connected(xprt))
941 xprt_force_disconnect(xprt);
942 return 0;
943}
944
945void rpc_clnt_disconnect(struct rpc_clnt *clnt)
946{
947 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
948}
949EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
950
951/*
952 * Properly shut down an RPC client, terminating all outstanding
953 * requests.
954 */
955void rpc_shutdown_client(struct rpc_clnt *clnt)
956{
957 might_sleep();
958
959 trace_rpc_clnt_shutdown(clnt);
960
961 clnt->cl_shutdown = 1;
962 while (!list_empty(&clnt->cl_tasks)) {
963 rpc_killall_tasks(clnt);
964 wait_event_timeout(destroy_wait,
965 list_empty(&clnt->cl_tasks), 1*HZ);
966 }
967
968 /* wait for tasks still in workqueue or waitqueue */
969 wait_event_timeout(destroy_wait,
970 atomic_read(&clnt->cl_task_count) == 0, 1 * HZ);
971
972 rpc_release_client(clnt);
973}
974EXPORT_SYMBOL_GPL(rpc_shutdown_client);
975
976/*
977 * Free an RPC client
978 */
979static void rpc_free_client_work(struct work_struct *work)
980{
981 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
982
983 trace_rpc_clnt_free(clnt);
984
985 /* These might block on processes that might allocate memory,
986 * so they cannot be called in rpciod, so they are handled separately
987 * here.
988 */
989 rpc_sysfs_client_destroy(clnt);
990 rpc_clnt_debugfs_unregister(clnt);
991 rpc_free_clid(clnt);
992 rpc_clnt_remove_pipedir(clnt);
993 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
994
995 kfree(clnt);
996 rpciod_down();
997}
998static struct rpc_clnt *
999rpc_free_client(struct rpc_clnt *clnt)
1000{
1001 struct rpc_clnt *parent = NULL;
1002
1003 trace_rpc_clnt_release(clnt);
1004 if (clnt->cl_parent != clnt)
1005 parent = clnt->cl_parent;
1006 rpc_unregister_client(clnt);
1007 rpc_free_iostats(clnt->cl_metrics);
1008 clnt->cl_metrics = NULL;
1009 xprt_iter_destroy(&clnt->cl_xpi);
1010 put_cred(clnt->cl_cred);
1011
1012 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
1013 schedule_work(&clnt->cl_work);
1014 return parent;
1015}
1016
1017/*
1018 * Free an RPC client
1019 */
1020static struct rpc_clnt *
1021rpc_free_auth(struct rpc_clnt *clnt)
1022{
1023 /*
1024 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
1025 * release remaining GSS contexts. This mechanism ensures
1026 * that it can do so safely.
1027 */
1028 if (clnt->cl_auth != NULL) {
1029 rpcauth_release(clnt->cl_auth);
1030 clnt->cl_auth = NULL;
1031 }
1032 if (refcount_dec_and_test(&clnt->cl_count))
1033 return rpc_free_client(clnt);
1034 return NULL;
1035}
1036
1037/*
1038 * Release reference to the RPC client
1039 */
1040void
1041rpc_release_client(struct rpc_clnt *clnt)
1042{
1043 do {
1044 if (list_empty(&clnt->cl_tasks))
1045 wake_up(&destroy_wait);
1046 if (refcount_dec_not_one(&clnt->cl_count))
1047 break;
1048 clnt = rpc_free_auth(clnt);
1049 } while (clnt != NULL);
1050}
1051EXPORT_SYMBOL_GPL(rpc_release_client);
1052
1053/**
1054 * rpc_bind_new_program - bind a new RPC program to an existing client
1055 * @old: old rpc_client
1056 * @program: rpc program to set
1057 * @vers: rpc program version
1058 *
1059 * Clones the rpc client and sets up a new RPC program. This is mainly
1060 * of use for enabling different RPC programs to share the same transport.
1061 * The Sun NFSv2/v3 ACL protocol can do this.
1062 */
1063struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1064 const struct rpc_program *program,
1065 u32 vers)
1066{
1067 struct rpc_create_args args = {
1068 .program = program,
1069 .prognumber = program->number,
1070 .version = vers,
1071 .authflavor = old->cl_auth->au_flavor,
1072 .cred = old->cl_cred,
1073 .stats = old->cl_stats,
1074 .timeout = old->cl_timeout,
1075 };
1076 struct rpc_clnt *clnt;
1077 int err;
1078
1079 clnt = __rpc_clone_client(&args, old);
1080 if (IS_ERR(clnt))
1081 goto out;
1082 err = rpc_ping(clnt);
1083 if (err != 0) {
1084 rpc_shutdown_client(clnt);
1085 clnt = ERR_PTR(err);
1086 }
1087out:
1088 return clnt;
1089}
1090EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1091
1092struct rpc_xprt *
1093rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1094{
1095 struct rpc_xprt_switch *xps;
1096
1097 if (!xprt)
1098 return NULL;
1099 rcu_read_lock();
1100 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1101 atomic_long_inc(&xps->xps_queuelen);
1102 rcu_read_unlock();
1103 atomic_long_inc(&xprt->queuelen);
1104
1105 return xprt;
1106}
1107
1108static void
1109rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1110{
1111 struct rpc_xprt_switch *xps;
1112
1113 atomic_long_dec(&xprt->queuelen);
1114 rcu_read_lock();
1115 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1116 atomic_long_dec(&xps->xps_queuelen);
1117 rcu_read_unlock();
1118
1119 xprt_put(xprt);
1120}
1121
1122void rpc_task_release_transport(struct rpc_task *task)
1123{
1124 struct rpc_xprt *xprt = task->tk_xprt;
1125
1126 if (xprt) {
1127 task->tk_xprt = NULL;
1128 if (task->tk_client)
1129 rpc_task_release_xprt(task->tk_client, xprt);
1130 else
1131 xprt_put(xprt);
1132 }
1133}
1134EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1135
1136void rpc_task_release_client(struct rpc_task *task)
1137{
1138 struct rpc_clnt *clnt = task->tk_client;
1139
1140 rpc_task_release_transport(task);
1141 if (clnt != NULL) {
1142 /* Remove from client task list */
1143 spin_lock(&clnt->cl_lock);
1144 list_del(&task->tk_task);
1145 spin_unlock(&clnt->cl_lock);
1146 task->tk_client = NULL;
1147 atomic_dec(&clnt->cl_task_count);
1148
1149 rpc_release_client(clnt);
1150 }
1151}
1152
1153static struct rpc_xprt *
1154rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1155{
1156 struct rpc_xprt *xprt;
1157
1158 rcu_read_lock();
1159 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1160 rcu_read_unlock();
1161 return rpc_task_get_xprt(clnt, xprt);
1162}
1163
1164static struct rpc_xprt *
1165rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1166{
1167 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1168}
1169
1170static
1171void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1172{
1173 if (task->tk_xprt) {
1174 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1175 (task->tk_flags & RPC_TASK_MOVEABLE)))
1176 return;
1177 xprt_release(task);
1178 xprt_put(task->tk_xprt);
1179 }
1180 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1181 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1182 else
1183 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1184}
1185
1186static
1187void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1188{
1189 rpc_task_set_transport(task, clnt);
1190 task->tk_client = clnt;
1191 refcount_inc(&clnt->cl_count);
1192 if (clnt->cl_softrtry)
1193 task->tk_flags |= RPC_TASK_SOFT;
1194 if (clnt->cl_softerr)
1195 task->tk_flags |= RPC_TASK_TIMEOUT;
1196 if (clnt->cl_noretranstimeo)
1197 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1198 if (clnt->cl_netunreach_fatal)
1199 task->tk_flags |= RPC_TASK_NETUNREACH_FATAL;
1200 atomic_inc(&clnt->cl_task_count);
1201}
1202
1203static void
1204rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1205{
1206 if (msg != NULL) {
1207 task->tk_msg.rpc_proc = msg->rpc_proc;
1208 task->tk_msg.rpc_argp = msg->rpc_argp;
1209 task->tk_msg.rpc_resp = msg->rpc_resp;
1210 task->tk_msg.rpc_cred = msg->rpc_cred;
1211 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1212 get_cred(task->tk_msg.rpc_cred);
1213 }
1214}
1215
1216/*
1217 * Default callback for async RPC calls
1218 */
1219static void
1220rpc_default_callback(struct rpc_task *task, void *data)
1221{
1222}
1223
1224static const struct rpc_call_ops rpc_default_ops = {
1225 .rpc_call_done = rpc_default_callback,
1226};
1227
1228/**
1229 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1230 * @task_setup_data: pointer to task initialisation data
1231 */
1232struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1233{
1234 struct rpc_task *task;
1235
1236 task = rpc_new_task(task_setup_data);
1237 if (IS_ERR(task))
1238 return task;
1239
1240 if (!RPC_IS_ASYNC(task))
1241 task->tk_flags |= RPC_TASK_CRED_NOREF;
1242
1243 rpc_task_set_client(task, task_setup_data->rpc_client);
1244 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1245
1246 if (task->tk_action == NULL)
1247 rpc_call_start(task);
1248
1249 atomic_inc(&task->tk_count);
1250 rpc_execute(task);
1251 return task;
1252}
1253EXPORT_SYMBOL_GPL(rpc_run_task);
1254
1255/**
1256 * rpc_call_sync - Perform a synchronous RPC call
1257 * @clnt: pointer to RPC client
1258 * @msg: RPC call parameters
1259 * @flags: RPC call flags
1260 */
1261int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1262{
1263 struct rpc_task *task;
1264 struct rpc_task_setup task_setup_data = {
1265 .rpc_client = clnt,
1266 .rpc_message = msg,
1267 .callback_ops = &rpc_default_ops,
1268 .flags = flags,
1269 };
1270 int status;
1271
1272 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1273 if (flags & RPC_TASK_ASYNC) {
1274 rpc_release_calldata(task_setup_data.callback_ops,
1275 task_setup_data.callback_data);
1276 return -EINVAL;
1277 }
1278
1279 task = rpc_run_task(&task_setup_data);
1280 if (IS_ERR(task))
1281 return PTR_ERR(task);
1282 status = task->tk_status;
1283 rpc_put_task(task);
1284 return status;
1285}
1286EXPORT_SYMBOL_GPL(rpc_call_sync);
1287
1288/**
1289 * rpc_call_async - Perform an asynchronous RPC call
1290 * @clnt: pointer to RPC client
1291 * @msg: RPC call parameters
1292 * @flags: RPC call flags
1293 * @tk_ops: RPC call ops
1294 * @data: user call data
1295 */
1296int
1297rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1298 const struct rpc_call_ops *tk_ops, void *data)
1299{
1300 struct rpc_task *task;
1301 struct rpc_task_setup task_setup_data = {
1302 .rpc_client = clnt,
1303 .rpc_message = msg,
1304 .callback_ops = tk_ops,
1305 .callback_data = data,
1306 .flags = flags|RPC_TASK_ASYNC,
1307 };
1308
1309 task = rpc_run_task(&task_setup_data);
1310 if (IS_ERR(task))
1311 return PTR_ERR(task);
1312 rpc_put_task(task);
1313 return 0;
1314}
1315EXPORT_SYMBOL_GPL(rpc_call_async);
1316
1317#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1318static void call_bc_encode(struct rpc_task *task);
1319
1320/**
1321 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1322 * rpc_execute against it
1323 * @req: RPC request
1324 * @timeout: timeout values to use for this task
1325 */
1326struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1327 struct rpc_timeout *timeout)
1328{
1329 struct rpc_task *task;
1330 struct rpc_task_setup task_setup_data = {
1331 .callback_ops = &rpc_default_ops,
1332 .flags = RPC_TASK_SOFTCONN |
1333 RPC_TASK_NO_RETRANS_TIMEOUT,
1334 };
1335
1336 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1337 /*
1338 * Create an rpc_task to send the data
1339 */
1340 task = rpc_new_task(&task_setup_data);
1341 if (IS_ERR(task)) {
1342 xprt_free_bc_request(req);
1343 return task;
1344 }
1345
1346 xprt_init_bc_request(req, task, timeout);
1347
1348 task->tk_action = call_bc_encode;
1349 atomic_inc(&task->tk_count);
1350 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1351 rpc_execute(task);
1352
1353 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1354 return task;
1355}
1356#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1357
1358/**
1359 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1360 * @req: RPC request to prepare
1361 * @pages: vector of struct page pointers
1362 * @base: offset in first page where receive should start, in bytes
1363 * @len: expected size of the upper layer data payload, in bytes
1364 * @hdrsize: expected size of upper layer reply header, in XDR words
1365 *
1366 */
1367void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1368 unsigned int base, unsigned int len,
1369 unsigned int hdrsize)
1370{
1371 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1372
1373 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1374 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1375}
1376EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1377
1378void
1379rpc_call_start(struct rpc_task *task)
1380{
1381 task->tk_action = call_start;
1382}
1383EXPORT_SYMBOL_GPL(rpc_call_start);
1384
1385/**
1386 * rpc_peeraddr - extract remote peer address from clnt's xprt
1387 * @clnt: RPC client structure
1388 * @buf: target buffer
1389 * @bufsize: length of target buffer
1390 *
1391 * Returns the number of bytes that are actually in the stored address.
1392 */
1393size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1394{
1395 size_t bytes;
1396 struct rpc_xprt *xprt;
1397
1398 rcu_read_lock();
1399 xprt = rcu_dereference(clnt->cl_xprt);
1400
1401 bytes = xprt->addrlen;
1402 if (bytes > bufsize)
1403 bytes = bufsize;
1404 memcpy(buf, &xprt->addr, bytes);
1405 rcu_read_unlock();
1406
1407 return bytes;
1408}
1409EXPORT_SYMBOL_GPL(rpc_peeraddr);
1410
1411/**
1412 * rpc_peeraddr2str - return remote peer address in printable format
1413 * @clnt: RPC client structure
1414 * @format: address format
1415 *
1416 * NB: the lifetime of the memory referenced by the returned pointer is
1417 * the same as the rpc_xprt itself. As long as the caller uses this
1418 * pointer, it must hold the RCU read lock.
1419 */
1420const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1421 enum rpc_display_format_t format)
1422{
1423 struct rpc_xprt *xprt;
1424
1425 xprt = rcu_dereference(clnt->cl_xprt);
1426
1427 if (xprt->address_strings[format] != NULL)
1428 return xprt->address_strings[format];
1429 else
1430 return "unprintable";
1431}
1432EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1433
1434static const struct sockaddr_in rpc_inaddr_loopback = {
1435 .sin_family = AF_INET,
1436 .sin_addr.s_addr = htonl(INADDR_ANY),
1437};
1438
1439static const struct sockaddr_in6 rpc_in6addr_loopback = {
1440 .sin6_family = AF_INET6,
1441 .sin6_addr = IN6ADDR_ANY_INIT,
1442};
1443
1444/*
1445 * Try a getsockname() on a connected datagram socket. Using a
1446 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1447 * This conserves the ephemeral port number space.
1448 *
1449 * Returns zero and fills in "buf" if successful; otherwise, a
1450 * negative errno is returned.
1451 */
1452static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1453 struct sockaddr *buf)
1454{
1455 struct socket *sock;
1456 int err;
1457
1458 err = __sock_create(net, sap->sa_family,
1459 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1460 if (err < 0) {
1461 dprintk("RPC: can't create UDP socket (%d)\n", err);
1462 goto out;
1463 }
1464
1465 switch (sap->sa_family) {
1466 case AF_INET:
1467 err = kernel_bind(sock,
1468 (struct sockaddr *)&rpc_inaddr_loopback,
1469 sizeof(rpc_inaddr_loopback));
1470 break;
1471 case AF_INET6:
1472 err = kernel_bind(sock,
1473 (struct sockaddr *)&rpc_in6addr_loopback,
1474 sizeof(rpc_in6addr_loopback));
1475 break;
1476 default:
1477 err = -EAFNOSUPPORT;
1478 goto out_release;
1479 }
1480 if (err < 0) {
1481 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1482 goto out_release;
1483 }
1484
1485 err = kernel_connect(sock, sap, salen, 0);
1486 if (err < 0) {
1487 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1488 goto out_release;
1489 }
1490
1491 err = kernel_getsockname(sock, buf);
1492 if (err < 0) {
1493 dprintk("RPC: getsockname failed (%d)\n", err);
1494 goto out_release;
1495 }
1496
1497 err = 0;
1498 if (buf->sa_family == AF_INET6) {
1499 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1500 sin6->sin6_scope_id = 0;
1501 }
1502 dprintk("RPC: %s succeeded\n", __func__);
1503
1504out_release:
1505 sock_release(sock);
1506out:
1507 return err;
1508}
1509
1510/*
1511 * Scraping a connected socket failed, so we don't have a useable
1512 * local address. Fallback: generate an address that will prevent
1513 * the server from calling us back.
1514 *
1515 * Returns zero and fills in "buf" if successful; otherwise, a
1516 * negative errno is returned.
1517 */
1518static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1519{
1520 switch (family) {
1521 case AF_INET:
1522 if (buflen < sizeof(rpc_inaddr_loopback))
1523 return -EINVAL;
1524 memcpy(buf, &rpc_inaddr_loopback,
1525 sizeof(rpc_inaddr_loopback));
1526 break;
1527 case AF_INET6:
1528 if (buflen < sizeof(rpc_in6addr_loopback))
1529 return -EINVAL;
1530 memcpy(buf, &rpc_in6addr_loopback,
1531 sizeof(rpc_in6addr_loopback));
1532 break;
1533 default:
1534 dprintk("RPC: %s: address family not supported\n",
1535 __func__);
1536 return -EAFNOSUPPORT;
1537 }
1538 dprintk("RPC: %s: succeeded\n", __func__);
1539 return 0;
1540}
1541
1542/**
1543 * rpc_localaddr - discover local endpoint address for an RPC client
1544 * @clnt: RPC client structure
1545 * @buf: target buffer
1546 * @buflen: size of target buffer, in bytes
1547 *
1548 * Returns zero and fills in "buf" and "buflen" if successful;
1549 * otherwise, a negative errno is returned.
1550 *
1551 * This works even if the underlying transport is not currently connected,
1552 * or if the upper layer never previously provided a source address.
1553 *
1554 * The result of this function call is transient: multiple calls in
1555 * succession may give different results, depending on how local
1556 * networking configuration changes over time.
1557 */
1558int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1559{
1560 struct sockaddr_storage address;
1561 struct sockaddr *sap = (struct sockaddr *)&address;
1562 struct rpc_xprt *xprt;
1563 struct net *net;
1564 size_t salen;
1565 int err;
1566
1567 rcu_read_lock();
1568 xprt = rcu_dereference(clnt->cl_xprt);
1569 salen = xprt->addrlen;
1570 memcpy(sap, &xprt->addr, salen);
1571 net = get_net(xprt->xprt_net);
1572 rcu_read_unlock();
1573
1574 rpc_set_port(sap, 0);
1575 err = rpc_sockname(net, sap, salen, buf);
1576 put_net(net);
1577 if (err != 0)
1578 /* Couldn't discover local address, return ANYADDR */
1579 return rpc_anyaddr(sap->sa_family, buf, buflen);
1580 return 0;
1581}
1582EXPORT_SYMBOL_GPL(rpc_localaddr);
1583
1584void
1585rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1586{
1587 struct rpc_xprt *xprt;
1588
1589 rcu_read_lock();
1590 xprt = rcu_dereference(clnt->cl_xprt);
1591 if (xprt->ops->set_buffer_size)
1592 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1593 rcu_read_unlock();
1594}
1595EXPORT_SYMBOL_GPL(rpc_setbufsize);
1596
1597/**
1598 * rpc_net_ns - Get the network namespace for this RPC client
1599 * @clnt: RPC client to query
1600 *
1601 */
1602struct net *rpc_net_ns(struct rpc_clnt *clnt)
1603{
1604 struct net *ret;
1605
1606 rcu_read_lock();
1607 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1608 rcu_read_unlock();
1609 return ret;
1610}
1611EXPORT_SYMBOL_GPL(rpc_net_ns);
1612
1613/**
1614 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1615 * @clnt: RPC client to query
1616 *
1617 * For stream transports, this is one RPC record fragment (see RFC
1618 * 1831), as we don't support multi-record requests yet. For datagram
1619 * transports, this is the size of an IP packet minus the IP, UDP, and
1620 * RPC header sizes.
1621 */
1622size_t rpc_max_payload(struct rpc_clnt *clnt)
1623{
1624 size_t ret;
1625
1626 rcu_read_lock();
1627 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1628 rcu_read_unlock();
1629 return ret;
1630}
1631EXPORT_SYMBOL_GPL(rpc_max_payload);
1632
1633/**
1634 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1635 * @clnt: RPC client to query
1636 */
1637size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1638{
1639 struct rpc_xprt *xprt;
1640 size_t ret;
1641
1642 rcu_read_lock();
1643 xprt = rcu_dereference(clnt->cl_xprt);
1644 ret = xprt->ops->bc_maxpayload(xprt);
1645 rcu_read_unlock();
1646 return ret;
1647}
1648EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1649
1650unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1651{
1652 struct rpc_xprt *xprt;
1653 unsigned int ret;
1654
1655 rcu_read_lock();
1656 xprt = rcu_dereference(clnt->cl_xprt);
1657 ret = xprt->ops->bc_num_slots(xprt);
1658 rcu_read_unlock();
1659 return ret;
1660}
1661EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1662
1663/**
1664 * rpc_force_rebind - force transport to check that remote port is unchanged
1665 * @clnt: client to rebind
1666 *
1667 */
1668void rpc_force_rebind(struct rpc_clnt *clnt)
1669{
1670 if (clnt->cl_autobind) {
1671 rcu_read_lock();
1672 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1673 rcu_read_unlock();
1674 }
1675}
1676EXPORT_SYMBOL_GPL(rpc_force_rebind);
1677
1678static int
1679__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1680{
1681 task->tk_status = 0;
1682 task->tk_rpc_status = 0;
1683 task->tk_action = action;
1684 return 1;
1685}
1686
1687/*
1688 * Restart an (async) RPC call. Usually called from within the
1689 * exit handler.
1690 */
1691int
1692rpc_restart_call(struct rpc_task *task)
1693{
1694 return __rpc_restart_call(task, call_start);
1695}
1696EXPORT_SYMBOL_GPL(rpc_restart_call);
1697
1698/*
1699 * Restart an (async) RPC call from the call_prepare state.
1700 * Usually called from within the exit handler.
1701 */
1702int
1703rpc_restart_call_prepare(struct rpc_task *task)
1704{
1705 if (task->tk_ops->rpc_call_prepare != NULL)
1706 return __rpc_restart_call(task, rpc_prepare_task);
1707 return rpc_restart_call(task);
1708}
1709EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1710
1711const char
1712*rpc_proc_name(const struct rpc_task *task)
1713{
1714 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1715
1716 if (proc) {
1717 if (proc->p_name)
1718 return proc->p_name;
1719 else
1720 return "NULL";
1721 } else
1722 return "no proc";
1723}
1724
1725static void
1726__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1727{
1728 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1729 rpc_task_set_rpc_status(task, rpc_status);
1730 rpc_exit(task, tk_status);
1731}
1732
1733static void
1734rpc_call_rpcerror(struct rpc_task *task, int status)
1735{
1736 __rpc_call_rpcerror(task, status, status);
1737}
1738
1739/*
1740 * 0. Initial state
1741 *
1742 * Other FSM states can be visited zero or more times, but
1743 * this state is visited exactly once for each RPC.
1744 */
1745static void
1746call_start(struct rpc_task *task)
1747{
1748 struct rpc_clnt *clnt = task->tk_client;
1749 int idx = task->tk_msg.rpc_proc->p_statidx;
1750
1751 trace_rpc_request(task);
1752
1753 if (task->tk_client->cl_shutdown) {
1754 rpc_call_rpcerror(task, -EIO);
1755 return;
1756 }
1757
1758 /* Increment call count (version might not be valid for ping) */
1759 if (clnt->cl_program->version[clnt->cl_vers])
1760 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1761 clnt->cl_stats->rpccnt++;
1762 task->tk_action = call_reserve;
1763 rpc_task_set_transport(task, clnt);
1764}
1765
1766/*
1767 * 1. Reserve an RPC call slot
1768 */
1769static void
1770call_reserve(struct rpc_task *task)
1771{
1772 task->tk_status = 0;
1773 task->tk_action = call_reserveresult;
1774 xprt_reserve(task);
1775}
1776
1777static void call_retry_reserve(struct rpc_task *task);
1778
1779/*
1780 * 1b. Grok the result of xprt_reserve()
1781 */
1782static void
1783call_reserveresult(struct rpc_task *task)
1784{
1785 int status = task->tk_status;
1786
1787 /*
1788 * After a call to xprt_reserve(), we must have either
1789 * a request slot or else an error status.
1790 */
1791 task->tk_status = 0;
1792 if (status >= 0) {
1793 if (task->tk_rqstp) {
1794 task->tk_action = call_refresh;
1795
1796 /* Add to the client's list of all tasks */
1797 spin_lock(&task->tk_client->cl_lock);
1798 if (list_empty(&task->tk_task))
1799 list_add_tail(&task->tk_task, &task->tk_client->cl_tasks);
1800 spin_unlock(&task->tk_client->cl_lock);
1801 return;
1802 }
1803 rpc_call_rpcerror(task, -EIO);
1804 return;
1805 }
1806
1807 switch (status) {
1808 case -ENOMEM:
1809 rpc_delay(task, HZ >> 2);
1810 fallthrough;
1811 case -EAGAIN: /* woken up; retry */
1812 task->tk_action = call_retry_reserve;
1813 return;
1814 default:
1815 rpc_call_rpcerror(task, status);
1816 }
1817}
1818
1819/*
1820 * 1c. Retry reserving an RPC call slot
1821 */
1822static void
1823call_retry_reserve(struct rpc_task *task)
1824{
1825 task->tk_status = 0;
1826 task->tk_action = call_reserveresult;
1827 xprt_retry_reserve(task);
1828}
1829
1830/*
1831 * 2. Bind and/or refresh the credentials
1832 */
1833static void
1834call_refresh(struct rpc_task *task)
1835{
1836 task->tk_action = call_refreshresult;
1837 task->tk_status = 0;
1838 task->tk_client->cl_stats->rpcauthrefresh++;
1839 rpcauth_refreshcred(task);
1840}
1841
1842/*
1843 * 2a. Process the results of a credential refresh
1844 */
1845static void
1846call_refreshresult(struct rpc_task *task)
1847{
1848 int status = task->tk_status;
1849
1850 task->tk_status = 0;
1851 task->tk_action = call_refresh;
1852 switch (status) {
1853 case 0:
1854 if (rpcauth_uptodatecred(task)) {
1855 task->tk_action = call_allocate;
1856 return;
1857 }
1858 /* Use rate-limiting and a max number of retries if refresh
1859 * had status 0 but failed to update the cred.
1860 */
1861 fallthrough;
1862 case -ETIMEDOUT:
1863 rpc_delay(task, 3*HZ);
1864 fallthrough;
1865 case -EAGAIN:
1866 status = -EACCES;
1867 if (!task->tk_cred_retry)
1868 break;
1869 task->tk_cred_retry--;
1870 trace_rpc_retry_refresh_status(task);
1871 return;
1872 case -EKEYEXPIRED:
1873 break;
1874 case -ENOMEM:
1875 rpc_delay(task, HZ >> 4);
1876 return;
1877 }
1878 trace_rpc_refresh_status(task);
1879 rpc_call_rpcerror(task, status);
1880}
1881
1882/*
1883 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1884 * (Note: buffer memory is freed in xprt_release).
1885 */
1886static void
1887call_allocate(struct rpc_task *task)
1888{
1889 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1890 struct rpc_rqst *req = task->tk_rqstp;
1891 struct rpc_xprt *xprt = req->rq_xprt;
1892 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1893 int status;
1894
1895 task->tk_status = 0;
1896 task->tk_action = call_encode;
1897
1898 if (req->rq_buffer)
1899 return;
1900
1901 /*
1902 * Calculate the size (in quads) of the RPC call
1903 * and reply headers, and convert both values
1904 * to byte sizes.
1905 */
1906 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1907 proc->p_arglen;
1908 req->rq_callsize <<= 2;
1909 /*
1910 * Note: the reply buffer must at minimum allocate enough space
1911 * for the 'struct accepted_reply' from RFC5531.
1912 */
1913 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1914 max_t(size_t, proc->p_replen, 2);
1915 req->rq_rcvsize <<= 2;
1916
1917 status = xprt->ops->buf_alloc(task);
1918 trace_rpc_buf_alloc(task, status);
1919 if (status == 0)
1920 return;
1921 if (status != -ENOMEM) {
1922 rpc_call_rpcerror(task, status);
1923 return;
1924 }
1925
1926 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1927 task->tk_action = call_allocate;
1928 rpc_delay(task, HZ>>4);
1929 return;
1930 }
1931
1932 rpc_call_rpcerror(task, -ERESTARTSYS);
1933}
1934
1935static int
1936rpc_task_need_encode(struct rpc_task *task)
1937{
1938 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1939 (!(task->tk_flags & RPC_TASK_SENT) ||
1940 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1941 xprt_request_need_retransmit(task));
1942}
1943
1944static void
1945rpc_xdr_encode(struct rpc_task *task)
1946{
1947 struct rpc_rqst *req = task->tk_rqstp;
1948 struct xdr_stream xdr;
1949
1950 xdr_buf_init(&req->rq_snd_buf,
1951 req->rq_buffer,
1952 req->rq_callsize);
1953 xdr_buf_init(&req->rq_rcv_buf,
1954 req->rq_rbuffer,
1955 req->rq_rcvsize);
1956
1957 req->rq_reply_bytes_recvd = 0;
1958 req->rq_snd_buf.head[0].iov_len = 0;
1959 xdr_init_encode(&xdr, &req->rq_snd_buf,
1960 req->rq_snd_buf.head[0].iov_base, req);
1961 if (rpc_encode_header(task, &xdr))
1962 return;
1963
1964 task->tk_status = rpcauth_wrap_req(task, &xdr);
1965}
1966
1967/*
1968 * 3. Encode arguments of an RPC call
1969 */
1970static void
1971call_encode(struct rpc_task *task)
1972{
1973 if (!rpc_task_need_encode(task))
1974 goto out;
1975
1976 /* Dequeue task from the receive queue while we're encoding */
1977 xprt_request_dequeue_xprt(task);
1978 /* Encode here so that rpcsec_gss can use correct sequence number. */
1979 rpc_xdr_encode(task);
1980 /* Add task to reply queue before transmission to avoid races */
1981 if (task->tk_status == 0 && rpc_reply_expected(task))
1982 task->tk_status = xprt_request_enqueue_receive(task);
1983 /* Did the encode result in an error condition? */
1984 if (task->tk_status != 0) {
1985 /* Was the error nonfatal? */
1986 switch (task->tk_status) {
1987 case -EAGAIN:
1988 case -ENOMEM:
1989 rpc_delay(task, HZ >> 4);
1990 break;
1991 case -EKEYEXPIRED:
1992 if (!task->tk_cred_retry) {
1993 rpc_call_rpcerror(task, task->tk_status);
1994 } else {
1995 task->tk_action = call_refresh;
1996 task->tk_cred_retry--;
1997 trace_rpc_retry_refresh_status(task);
1998 }
1999 break;
2000 default:
2001 rpc_call_rpcerror(task, task->tk_status);
2002 }
2003 return;
2004 }
2005
2006 xprt_request_enqueue_transmit(task);
2007out:
2008 task->tk_action = call_transmit;
2009 /* Check that the connection is OK */
2010 if (!xprt_bound(task->tk_xprt))
2011 task->tk_action = call_bind;
2012 else if (!xprt_connected(task->tk_xprt))
2013 task->tk_action = call_connect;
2014}
2015
2016/*
2017 * Helpers to check if the task was already transmitted, and
2018 * to take action when that is the case.
2019 */
2020static bool
2021rpc_task_transmitted(struct rpc_task *task)
2022{
2023 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
2024}
2025
2026static void
2027rpc_task_handle_transmitted(struct rpc_task *task)
2028{
2029 xprt_end_transmit(task);
2030 task->tk_action = call_transmit_status;
2031}
2032
2033/*
2034 * 4. Get the server port number if not yet set
2035 */
2036static void
2037call_bind(struct rpc_task *task)
2038{
2039 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2040
2041 if (rpc_task_transmitted(task)) {
2042 rpc_task_handle_transmitted(task);
2043 return;
2044 }
2045
2046 if (xprt_bound(xprt)) {
2047 task->tk_action = call_connect;
2048 return;
2049 }
2050
2051 task->tk_action = call_bind_status;
2052 if (!xprt_prepare_transmit(task))
2053 return;
2054
2055 xprt->ops->rpcbind(task);
2056}
2057
2058/*
2059 * 4a. Sort out bind result
2060 */
2061static void
2062call_bind_status(struct rpc_task *task)
2063{
2064 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2065 int status = -EIO;
2066
2067 if (rpc_task_transmitted(task)) {
2068 rpc_task_handle_transmitted(task);
2069 return;
2070 }
2071
2072 if (task->tk_status >= 0)
2073 goto out_next;
2074 if (xprt_bound(xprt)) {
2075 task->tk_status = 0;
2076 goto out_next;
2077 }
2078
2079 switch (task->tk_status) {
2080 case -ENOMEM:
2081 rpc_delay(task, HZ >> 2);
2082 goto retry_timeout;
2083 case -EACCES:
2084 trace_rpcb_prog_unavail_err(task);
2085 /* fail immediately if this is an RPC ping */
2086 if (task->tk_msg.rpc_proc->p_proc == 0) {
2087 status = -EOPNOTSUPP;
2088 break;
2089 }
2090 rpc_delay(task, 3*HZ);
2091 goto retry_timeout;
2092 case -ENOBUFS:
2093 rpc_delay(task, HZ >> 2);
2094 goto retry_timeout;
2095 case -EAGAIN:
2096 goto retry_timeout;
2097 case -ETIMEDOUT:
2098 trace_rpcb_timeout_err(task);
2099 goto retry_timeout;
2100 case -EPFNOSUPPORT:
2101 /* server doesn't support any rpcbind version we know of */
2102 trace_rpcb_bind_version_err(task);
2103 break;
2104 case -EPROTONOSUPPORT:
2105 trace_rpcb_bind_version_err(task);
2106 goto retry_timeout;
2107 case -ENETDOWN:
2108 case -ENETUNREACH:
2109 if (task->tk_flags & RPC_TASK_NETUNREACH_FATAL)
2110 break;
2111 fallthrough;
2112 case -ECONNREFUSED: /* connection problems */
2113 case -ECONNRESET:
2114 case -ECONNABORTED:
2115 case -ENOTCONN:
2116 case -EHOSTDOWN:
2117 case -EHOSTUNREACH:
2118 case -EPIPE:
2119 trace_rpcb_unreachable_err(task);
2120 if (!RPC_IS_SOFTCONN(task)) {
2121 rpc_delay(task, 5*HZ);
2122 goto retry_timeout;
2123 }
2124 status = task->tk_status;
2125 break;
2126 default:
2127 trace_rpcb_unrecognized_err(task);
2128 }
2129
2130 rpc_call_rpcerror(task, status);
2131 return;
2132out_next:
2133 task->tk_action = call_connect;
2134 return;
2135retry_timeout:
2136 task->tk_status = 0;
2137 task->tk_action = call_bind;
2138 rpc_check_timeout(task);
2139}
2140
2141/*
2142 * 4b. Connect to the RPC server
2143 */
2144static void
2145call_connect(struct rpc_task *task)
2146{
2147 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2148
2149 if (rpc_task_transmitted(task)) {
2150 rpc_task_handle_transmitted(task);
2151 return;
2152 }
2153
2154 if (xprt_connected(xprt)) {
2155 task->tk_action = call_transmit;
2156 return;
2157 }
2158
2159 task->tk_action = call_connect_status;
2160 if (task->tk_status < 0)
2161 return;
2162 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2163 rpc_call_rpcerror(task, -ENOTCONN);
2164 return;
2165 }
2166 if (!xprt_prepare_transmit(task))
2167 return;
2168 xprt_connect(task);
2169}
2170
2171/*
2172 * 4c. Sort out connect result
2173 */
2174static void
2175call_connect_status(struct rpc_task *task)
2176{
2177 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2178 struct rpc_clnt *clnt = task->tk_client;
2179 int status = task->tk_status;
2180
2181 if (rpc_task_transmitted(task)) {
2182 rpc_task_handle_transmitted(task);
2183 return;
2184 }
2185
2186 trace_rpc_connect_status(task);
2187
2188 if (task->tk_status == 0) {
2189 clnt->cl_stats->netreconn++;
2190 goto out_next;
2191 }
2192 if (xprt_connected(xprt)) {
2193 task->tk_status = 0;
2194 goto out_next;
2195 }
2196
2197 task->tk_status = 0;
2198 switch (status) {
2199 case -ENETDOWN:
2200 case -ENETUNREACH:
2201 if (task->tk_flags & RPC_TASK_NETUNREACH_FATAL)
2202 break;
2203 fallthrough;
2204 case -ECONNREFUSED:
2205 case -ECONNRESET:
2206 /* A positive refusal suggests a rebind is needed. */
2207 if (clnt->cl_autobind) {
2208 rpc_force_rebind(clnt);
2209 if (RPC_IS_SOFTCONN(task))
2210 break;
2211 goto out_retry;
2212 }
2213 fallthrough;
2214 case -ECONNABORTED:
2215 case -EHOSTUNREACH:
2216 case -EPIPE:
2217 case -EPROTO:
2218 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2219 task->tk_rqstp->rq_connect_cookie);
2220 if (RPC_IS_SOFTCONN(task))
2221 break;
2222 /* retry with existing socket, after a delay */
2223 rpc_delay(task, 3*HZ);
2224 fallthrough;
2225 case -EADDRINUSE:
2226 case -ENOTCONN:
2227 case -EAGAIN:
2228 case -ETIMEDOUT:
2229 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2230 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2231 test_bit(XPRT_REMOVE, &xprt->state)) {
2232 struct rpc_xprt *saved = task->tk_xprt;
2233 struct rpc_xprt_switch *xps;
2234
2235 xps = rpc_clnt_xprt_switch_get(clnt);
2236 if (xps->xps_nxprts > 1) {
2237 long value;
2238
2239 xprt_release(task);
2240 value = atomic_long_dec_return(&xprt->queuelen);
2241 if (value == 0)
2242 rpc_xprt_switch_remove_xprt(xps, saved,
2243 true);
2244 xprt_put(saved);
2245 task->tk_xprt = NULL;
2246 task->tk_action = call_start;
2247 }
2248 xprt_switch_put(xps);
2249 if (!task->tk_xprt)
2250 goto out;
2251 }
2252 goto out_retry;
2253 case -ENOBUFS:
2254 rpc_delay(task, HZ >> 2);
2255 goto out_retry;
2256 }
2257 rpc_call_rpcerror(task, status);
2258 return;
2259out_next:
2260 task->tk_action = call_transmit;
2261 return;
2262out_retry:
2263 /* Check for timeouts before looping back to call_bind */
2264 task->tk_action = call_bind;
2265out:
2266 rpc_check_timeout(task);
2267}
2268
2269/*
2270 * 5. Transmit the RPC request, and wait for reply
2271 */
2272static void
2273call_transmit(struct rpc_task *task)
2274{
2275 if (rpc_task_transmitted(task)) {
2276 rpc_task_handle_transmitted(task);
2277 return;
2278 }
2279
2280 task->tk_action = call_transmit_status;
2281 if (!xprt_prepare_transmit(task))
2282 return;
2283 task->tk_status = 0;
2284 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2285 if (!xprt_connected(task->tk_xprt)) {
2286 task->tk_status = -ENOTCONN;
2287 return;
2288 }
2289 xprt_transmit(task);
2290 }
2291 xprt_end_transmit(task);
2292}
2293
2294/*
2295 * 5a. Handle cleanup after a transmission
2296 */
2297static void
2298call_transmit_status(struct rpc_task *task)
2299{
2300 task->tk_action = call_status;
2301
2302 /*
2303 * Common case: success. Force the compiler to put this
2304 * test first.
2305 */
2306 if (rpc_task_transmitted(task)) {
2307 task->tk_status = 0;
2308 xprt_request_wait_receive(task);
2309 return;
2310 }
2311
2312 switch (task->tk_status) {
2313 default:
2314 break;
2315 case -EBADMSG:
2316 task->tk_status = 0;
2317 task->tk_action = call_encode;
2318 break;
2319 /*
2320 * Special cases: if we've been waiting on the
2321 * socket's write_space() callback, or if the
2322 * socket just returned a connection error,
2323 * then hold onto the transport lock.
2324 */
2325 case -ENOMEM:
2326 case -ENOBUFS:
2327 rpc_delay(task, HZ>>2);
2328 fallthrough;
2329 case -EBADSLT:
2330 case -EAGAIN:
2331 task->tk_action = call_transmit;
2332 task->tk_status = 0;
2333 break;
2334 case -EHOSTDOWN:
2335 case -ENETDOWN:
2336 case -EHOSTUNREACH:
2337 case -ENETUNREACH:
2338 case -EPERM:
2339 break;
2340 case -ECONNREFUSED:
2341 if (RPC_IS_SOFTCONN(task)) {
2342 if (!task->tk_msg.rpc_proc->p_proc)
2343 trace_xprt_ping(task->tk_xprt,
2344 task->tk_status);
2345 rpc_call_rpcerror(task, task->tk_status);
2346 return;
2347 }
2348 fallthrough;
2349 case -ECONNRESET:
2350 case -ECONNABORTED:
2351 case -EADDRINUSE:
2352 case -ENOTCONN:
2353 case -EPIPE:
2354 task->tk_action = call_bind;
2355 task->tk_status = 0;
2356 break;
2357 }
2358 rpc_check_timeout(task);
2359}
2360
2361#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2362static void call_bc_transmit(struct rpc_task *task);
2363static void call_bc_transmit_status(struct rpc_task *task);
2364
2365static void
2366call_bc_encode(struct rpc_task *task)
2367{
2368 xprt_request_enqueue_transmit(task);
2369 task->tk_action = call_bc_transmit;
2370}
2371
2372/*
2373 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2374 * addition, disconnect on connectivity errors.
2375 */
2376static void
2377call_bc_transmit(struct rpc_task *task)
2378{
2379 task->tk_action = call_bc_transmit_status;
2380 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2381 if (!xprt_prepare_transmit(task))
2382 return;
2383 task->tk_status = 0;
2384 xprt_transmit(task);
2385 }
2386 xprt_end_transmit(task);
2387}
2388
2389static void
2390call_bc_transmit_status(struct rpc_task *task)
2391{
2392 struct rpc_rqst *req = task->tk_rqstp;
2393
2394 if (rpc_task_transmitted(task))
2395 task->tk_status = 0;
2396
2397 switch (task->tk_status) {
2398 case 0:
2399 /* Success */
2400 case -ENETDOWN:
2401 case -EHOSTDOWN:
2402 case -EHOSTUNREACH:
2403 case -ENETUNREACH:
2404 case -ECONNRESET:
2405 case -ECONNREFUSED:
2406 case -EADDRINUSE:
2407 case -ENOTCONN:
2408 case -EPIPE:
2409 break;
2410 case -ENOMEM:
2411 case -ENOBUFS:
2412 rpc_delay(task, HZ>>2);
2413 fallthrough;
2414 case -EBADSLT:
2415 case -EAGAIN:
2416 task->tk_status = 0;
2417 task->tk_action = call_bc_transmit;
2418 return;
2419 case -ETIMEDOUT:
2420 /*
2421 * Problem reaching the server. Disconnect and let the
2422 * forechannel reestablish the connection. The server will
2423 * have to retransmit the backchannel request and we'll
2424 * reprocess it. Since these ops are idempotent, there's no
2425 * need to cache our reply at this time.
2426 */
2427 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2428 "error: %d\n", task->tk_status);
2429 xprt_conditional_disconnect(req->rq_xprt,
2430 req->rq_connect_cookie);
2431 break;
2432 default:
2433 /*
2434 * We were unable to reply and will have to drop the
2435 * request. The server should reconnect and retransmit.
2436 */
2437 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2438 "error: %d\n", task->tk_status);
2439 break;
2440 }
2441 task->tk_action = rpc_exit_task;
2442}
2443#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2444
2445/*
2446 * 6. Sort out the RPC call status
2447 */
2448static void
2449call_status(struct rpc_task *task)
2450{
2451 struct rpc_clnt *clnt = task->tk_client;
2452 int status;
2453
2454 if (!task->tk_msg.rpc_proc->p_proc)
2455 trace_xprt_ping(task->tk_xprt, task->tk_status);
2456
2457 status = task->tk_status;
2458 if (status >= 0) {
2459 task->tk_action = call_decode;
2460 return;
2461 }
2462
2463 trace_rpc_call_status(task);
2464 task->tk_status = 0;
2465 switch(status) {
2466 case -ENETDOWN:
2467 case -ENETUNREACH:
2468 if (task->tk_flags & RPC_TASK_NETUNREACH_FATAL)
2469 goto out_exit;
2470 fallthrough;
2471 case -EHOSTDOWN:
2472 case -EHOSTUNREACH:
2473 case -EPERM:
2474 if (RPC_IS_SOFTCONN(task))
2475 goto out_exit;
2476 /*
2477 * Delay any retries for 3 seconds, then handle as if it
2478 * were a timeout.
2479 */
2480 rpc_delay(task, 3*HZ);
2481 fallthrough;
2482 case -ETIMEDOUT:
2483 break;
2484 case -ECONNREFUSED:
2485 case -ECONNRESET:
2486 case -ECONNABORTED:
2487 case -ENOTCONN:
2488 rpc_force_rebind(clnt);
2489 break;
2490 case -EADDRINUSE:
2491 rpc_delay(task, 3*HZ);
2492 fallthrough;
2493 case -EPIPE:
2494 case -EAGAIN:
2495 break;
2496 case -ENFILE:
2497 case -ENOBUFS:
2498 case -ENOMEM:
2499 rpc_delay(task, HZ>>2);
2500 break;
2501 case -EIO:
2502 /* shutdown or soft timeout */
2503 goto out_exit;
2504 default:
2505 if (clnt->cl_chatty)
2506 printk("%s: RPC call returned error %d\n",
2507 clnt->cl_program->name, -status);
2508 goto out_exit;
2509 }
2510 task->tk_action = call_encode;
2511 rpc_check_timeout(task);
2512 return;
2513out_exit:
2514 rpc_call_rpcerror(task, status);
2515}
2516
2517static bool
2518rpc_check_connected(const struct rpc_rqst *req)
2519{
2520 /* No allocated request or transport? return true */
2521 if (!req || !req->rq_xprt)
2522 return true;
2523 return xprt_connected(req->rq_xprt);
2524}
2525
2526static void
2527rpc_check_timeout(struct rpc_task *task)
2528{
2529 struct rpc_clnt *clnt = task->tk_client;
2530
2531 if (RPC_SIGNALLED(task))
2532 return;
2533
2534 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2535 return;
2536
2537 trace_rpc_timeout_status(task);
2538 task->tk_timeouts++;
2539
2540 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2541 rpc_call_rpcerror(task, -ETIMEDOUT);
2542 return;
2543 }
2544
2545 if (RPC_IS_SOFT(task)) {
2546 /*
2547 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2548 * been sent, it should time out only if the transport
2549 * connection gets terminally broken.
2550 */
2551 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2552 rpc_check_connected(task->tk_rqstp))
2553 return;
2554
2555 if (clnt->cl_chatty) {
2556 pr_notice_ratelimited(
2557 "%s: server %s not responding, timed out\n",
2558 clnt->cl_program->name,
2559 task->tk_xprt->servername);
2560 }
2561 if (task->tk_flags & RPC_TASK_TIMEOUT)
2562 rpc_call_rpcerror(task, -ETIMEDOUT);
2563 else
2564 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2565 return;
2566 }
2567
2568 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2569 task->tk_flags |= RPC_CALL_MAJORSEEN;
2570 if (clnt->cl_chatty) {
2571 pr_notice_ratelimited(
2572 "%s: server %s not responding, still trying\n",
2573 clnt->cl_program->name,
2574 task->tk_xprt->servername);
2575 }
2576 }
2577 rpc_force_rebind(clnt);
2578 /*
2579 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2580 * event? RFC2203 requires the server to drop all such requests.
2581 */
2582 rpcauth_invalcred(task);
2583}
2584
2585/*
2586 * 7. Decode the RPC reply
2587 */
2588static void
2589call_decode(struct rpc_task *task)
2590{
2591 struct rpc_clnt *clnt = task->tk_client;
2592 struct rpc_rqst *req = task->tk_rqstp;
2593 struct xdr_stream xdr;
2594 int err;
2595
2596 if (!task->tk_msg.rpc_proc->p_decode) {
2597 task->tk_action = rpc_exit_task;
2598 return;
2599 }
2600
2601 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2602 if (clnt->cl_chatty) {
2603 pr_notice_ratelimited("%s: server %s OK\n",
2604 clnt->cl_program->name,
2605 task->tk_xprt->servername);
2606 }
2607 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2608 }
2609
2610 /*
2611 * Did we ever call xprt_complete_rqst()? If not, we should assume
2612 * the message is incomplete.
2613 */
2614 err = -EAGAIN;
2615 if (!req->rq_reply_bytes_recvd)
2616 goto out;
2617
2618 /* Ensure that we see all writes made by xprt_complete_rqst()
2619 * before it changed req->rq_reply_bytes_recvd.
2620 */
2621 smp_rmb();
2622
2623 req->rq_rcv_buf.len = req->rq_private_buf.len;
2624 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2625
2626 /* Check that the softirq receive buffer is valid */
2627 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2628 sizeof(req->rq_rcv_buf)) != 0);
2629
2630 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2631 req->rq_rcv_buf.head[0].iov_base, req);
2632 err = rpc_decode_header(task, &xdr);
2633out:
2634 switch (err) {
2635 case 0:
2636 task->tk_action = rpc_exit_task;
2637 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2638 xdr_finish_decode(&xdr);
2639 return;
2640 case -EAGAIN:
2641 task->tk_status = 0;
2642 if (task->tk_client->cl_discrtry)
2643 xprt_conditional_disconnect(req->rq_xprt,
2644 req->rq_connect_cookie);
2645 task->tk_action = call_encode;
2646 rpc_check_timeout(task);
2647 break;
2648 case -EKEYREJECTED:
2649 task->tk_action = call_reserve;
2650 rpc_check_timeout(task);
2651 rpcauth_invalcred(task);
2652 /* Ensure we obtain a new XID if we retry! */
2653 xprt_release(task);
2654 }
2655}
2656
2657static int
2658rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2659{
2660 struct rpc_clnt *clnt = task->tk_client;
2661 struct rpc_rqst *req = task->tk_rqstp;
2662 __be32 *p;
2663 int error;
2664
2665 error = -EMSGSIZE;
2666 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2667 if (!p)
2668 goto out_fail;
2669 *p++ = req->rq_xid;
2670 *p++ = rpc_call;
2671 *p++ = cpu_to_be32(RPC_VERSION);
2672 *p++ = cpu_to_be32(clnt->cl_prog);
2673 *p++ = cpu_to_be32(clnt->cl_vers);
2674 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2675
2676 error = rpcauth_marshcred(task, xdr);
2677 if (error < 0)
2678 goto out_fail;
2679 return 0;
2680out_fail:
2681 trace_rpc_bad_callhdr(task);
2682 rpc_call_rpcerror(task, error);
2683 return error;
2684}
2685
2686static noinline int
2687rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2688{
2689 struct rpc_clnt *clnt = task->tk_client;
2690 int error;
2691 __be32 *p;
2692
2693 /* RFC-1014 says that the representation of XDR data must be a
2694 * multiple of four bytes
2695 * - if it isn't pointer subtraction in the NFS client may give
2696 * undefined results
2697 */
2698 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2699 goto out_unparsable;
2700
2701 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2702 if (!p)
2703 goto out_unparsable;
2704 p++; /* skip XID */
2705 if (*p++ != rpc_reply)
2706 goto out_unparsable;
2707 if (*p++ != rpc_msg_accepted)
2708 goto out_msg_denied;
2709
2710 error = rpcauth_checkverf(task, xdr);
2711 if (error) {
2712 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
2713
2714 if (!test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
2715 rpcauth_invalcred(task);
2716 if (!task->tk_cred_retry)
2717 goto out_err;
2718 task->tk_cred_retry--;
2719 trace_rpc__stale_creds(task);
2720 return -EKEYREJECTED;
2721 }
2722 goto out_verifier;
2723 }
2724
2725 p = xdr_inline_decode(xdr, sizeof(*p));
2726 if (!p)
2727 goto out_unparsable;
2728 switch (*p) {
2729 case rpc_success:
2730 return 0;
2731 case rpc_prog_unavail:
2732 trace_rpc__prog_unavail(task);
2733 error = -EPFNOSUPPORT;
2734 goto out_err;
2735 case rpc_prog_mismatch:
2736 trace_rpc__prog_mismatch(task);
2737 error = -EPROTONOSUPPORT;
2738 goto out_err;
2739 case rpc_proc_unavail:
2740 trace_rpc__proc_unavail(task);
2741 error = -EOPNOTSUPP;
2742 goto out_err;
2743 case rpc_garbage_args:
2744 case rpc_system_err:
2745 trace_rpc__garbage_args(task);
2746 error = -EIO;
2747 break;
2748 default:
2749 goto out_unparsable;
2750 }
2751
2752out_garbage:
2753 clnt->cl_stats->rpcgarbage++;
2754 if (task->tk_garb_retry) {
2755 task->tk_garb_retry--;
2756 task->tk_action = call_encode;
2757 return -EAGAIN;
2758 }
2759out_err:
2760 rpc_call_rpcerror(task, error);
2761 return error;
2762
2763out_unparsable:
2764 trace_rpc__unparsable(task);
2765 error = -EIO;
2766 goto out_garbage;
2767
2768out_verifier:
2769 trace_rpc_bad_verifier(task);
2770 switch (error) {
2771 case -EPROTONOSUPPORT:
2772 goto out_err;
2773 case -EACCES:
2774 /* possible RPCSEC_GSS out-of-sequence event (RFC2203),
2775 * reset recv state and keep waiting, don't retransmit
2776 */
2777 task->tk_rqstp->rq_reply_bytes_recvd = 0;
2778 task->tk_status = xprt_request_enqueue_receive(task);
2779 task->tk_action = call_transmit_status;
2780 return -EBADMSG;
2781 default:
2782 goto out_garbage;
2783 }
2784
2785out_msg_denied:
2786 error = -EACCES;
2787 p = xdr_inline_decode(xdr, sizeof(*p));
2788 if (!p)
2789 goto out_unparsable;
2790 switch (*p++) {
2791 case rpc_auth_error:
2792 break;
2793 case rpc_mismatch:
2794 trace_rpc__mismatch(task);
2795 error = -EPROTONOSUPPORT;
2796 goto out_err;
2797 default:
2798 goto out_unparsable;
2799 }
2800
2801 p = xdr_inline_decode(xdr, sizeof(*p));
2802 if (!p)
2803 goto out_unparsable;
2804 switch (*p++) {
2805 case rpc_autherr_rejectedcred:
2806 case rpc_autherr_rejectedverf:
2807 case rpcsec_gsserr_credproblem:
2808 case rpcsec_gsserr_ctxproblem:
2809 rpcauth_invalcred(task);
2810 if (!task->tk_cred_retry)
2811 break;
2812 task->tk_cred_retry--;
2813 trace_rpc__stale_creds(task);
2814 return -EKEYREJECTED;
2815 case rpc_autherr_badcred:
2816 case rpc_autherr_badverf:
2817 /* possibly garbled cred/verf? */
2818 if (!task->tk_garb_retry)
2819 break;
2820 task->tk_garb_retry--;
2821 trace_rpc__bad_creds(task);
2822 task->tk_action = call_encode;
2823 return -EAGAIN;
2824 case rpc_autherr_tooweak:
2825 trace_rpc__auth_tooweak(task);
2826 pr_warn("RPC: server %s requires stronger authentication.\n",
2827 task->tk_xprt->servername);
2828 break;
2829 default:
2830 goto out_unparsable;
2831 }
2832 goto out_err;
2833}
2834
2835static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2836 const void *obj)
2837{
2838}
2839
2840static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2841 void *obj)
2842{
2843 return 0;
2844}
2845
2846static const struct rpc_procinfo rpcproc_null = {
2847 .p_encode = rpcproc_encode_null,
2848 .p_decode = rpcproc_decode_null,
2849};
2850
2851static const struct rpc_procinfo rpcproc_null_noreply = {
2852 .p_encode = rpcproc_encode_null,
2853};
2854
2855static void
2856rpc_null_call_prepare(struct rpc_task *task, void *data)
2857{
2858 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2859 rpc_call_start(task);
2860}
2861
2862static const struct rpc_call_ops rpc_null_ops = {
2863 .rpc_call_prepare = rpc_null_call_prepare,
2864 .rpc_call_done = rpc_default_callback,
2865};
2866
2867static
2868struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2869 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2870 const struct rpc_call_ops *ops, void *data)
2871{
2872 struct rpc_message msg = {
2873 .rpc_proc = &rpcproc_null,
2874 };
2875 struct rpc_task_setup task_setup_data = {
2876 .rpc_client = clnt,
2877 .rpc_xprt = xprt,
2878 .rpc_message = &msg,
2879 .rpc_op_cred = cred,
2880 .callback_ops = ops ?: &rpc_null_ops,
2881 .callback_data = data,
2882 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2883 RPC_TASK_NULLCREDS,
2884 };
2885
2886 return rpc_run_task(&task_setup_data);
2887}
2888
2889struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2890{
2891 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2892}
2893EXPORT_SYMBOL_GPL(rpc_call_null);
2894
2895static int rpc_ping(struct rpc_clnt *clnt)
2896{
2897 struct rpc_task *task;
2898 int status;
2899
2900 if (clnt->cl_auth->au_ops->ping)
2901 return clnt->cl_auth->au_ops->ping(clnt);
2902
2903 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2904 if (IS_ERR(task))
2905 return PTR_ERR(task);
2906 status = task->tk_status;
2907 rpc_put_task(task);
2908 return status;
2909}
2910
2911static int rpc_ping_noreply(struct rpc_clnt *clnt)
2912{
2913 struct rpc_message msg = {
2914 .rpc_proc = &rpcproc_null_noreply,
2915 };
2916 struct rpc_task_setup task_setup_data = {
2917 .rpc_client = clnt,
2918 .rpc_message = &msg,
2919 .callback_ops = &rpc_null_ops,
2920 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2921 };
2922 struct rpc_task *task;
2923 int status;
2924
2925 task = rpc_run_task(&task_setup_data);
2926 if (IS_ERR(task))
2927 return PTR_ERR(task);
2928 status = task->tk_status;
2929 rpc_put_task(task);
2930 return status;
2931}
2932
2933struct rpc_cb_add_xprt_calldata {
2934 struct rpc_xprt_switch *xps;
2935 struct rpc_xprt *xprt;
2936};
2937
2938static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2939{
2940 struct rpc_cb_add_xprt_calldata *data = calldata;
2941
2942 if (task->tk_status == 0)
2943 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2944}
2945
2946static void rpc_cb_add_xprt_release(void *calldata)
2947{
2948 struct rpc_cb_add_xprt_calldata *data = calldata;
2949
2950 xprt_put(data->xprt);
2951 xprt_switch_put(data->xps);
2952 kfree(data);
2953}
2954
2955static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2956 .rpc_call_prepare = rpc_null_call_prepare,
2957 .rpc_call_done = rpc_cb_add_xprt_done,
2958 .rpc_release = rpc_cb_add_xprt_release,
2959};
2960
2961/**
2962 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2963 * @clnt: pointer to struct rpc_clnt
2964 * @xps: pointer to struct rpc_xprt_switch,
2965 * @xprt: pointer struct rpc_xprt
2966 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport
2967 */
2968int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2969 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2970 void *in_max_connect)
2971{
2972 struct rpc_cb_add_xprt_calldata *data;
2973 struct rpc_task *task;
2974 int max_connect = clnt->cl_max_connect;
2975
2976 if (in_max_connect)
2977 max_connect = *(int *)in_max_connect;
2978 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) {
2979 rcu_read_lock();
2980 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2981 "transport to server: %s\n", max_connect,
2982 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2983 rcu_read_unlock();
2984 return -EINVAL;
2985 }
2986
2987 data = kmalloc(sizeof(*data), GFP_KERNEL);
2988 if (!data)
2989 return -ENOMEM;
2990 data->xps = xprt_switch_get(xps);
2991 data->xprt = xprt_get(xprt);
2992 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2993 rpc_cb_add_xprt_release(data);
2994 goto success;
2995 }
2996
2997 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2998 &rpc_cb_add_xprt_call_ops, data);
2999 if (IS_ERR(task))
3000 return PTR_ERR(task);
3001
3002 data->xps->xps_nunique_destaddr_xprts++;
3003 rpc_put_task(task);
3004success:
3005 return 1;
3006}
3007EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
3008
3009static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
3010 struct rpc_xprt *xprt,
3011 struct rpc_add_xprt_test *data)
3012{
3013 struct rpc_task *task;
3014 int status = -EADDRINUSE;
3015
3016 /* Test the connection */
3017 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
3018 if (IS_ERR(task))
3019 return PTR_ERR(task);
3020
3021 status = task->tk_status;
3022 rpc_put_task(task);
3023
3024 if (status < 0)
3025 return status;
3026
3027 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
3028 data->add_xprt_test(clnt, xprt, data->data);
3029
3030 return 0;
3031}
3032
3033/**
3034 * rpc_clnt_setup_test_and_add_xprt()
3035 *
3036 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
3037 * 1) caller of the test function must dereference the rpc_xprt_switch
3038 * and the rpc_xprt.
3039 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
3040 * the rpc_call_done routine.
3041 *
3042 * Upon success (return of 1), the test function adds the new
3043 * transport to the rpc_clnt xprt switch
3044 *
3045 * @clnt: struct rpc_clnt to get the new transport
3046 * @xps: the rpc_xprt_switch to hold the new transport
3047 * @xprt: the rpc_xprt to test
3048 * @data: a struct rpc_add_xprt_test pointer that holds the test function
3049 * and test function call data
3050 */
3051int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
3052 struct rpc_xprt_switch *xps,
3053 struct rpc_xprt *xprt,
3054 void *data)
3055{
3056 int status = -EADDRINUSE;
3057
3058 xprt = xprt_get(xprt);
3059 xprt_switch_get(xps);
3060
3061 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
3062 goto out_err;
3063
3064 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3065 if (status < 0)
3066 goto out_err;
3067
3068 status = 1;
3069out_err:
3070 xprt_put(xprt);
3071 xprt_switch_put(xps);
3072 if (status < 0)
3073 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3074 "added\n", status,
3075 xprt->address_strings[RPC_DISPLAY_ADDR]);
3076 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3077 return status;
3078}
3079EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3080
3081/**
3082 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3083 * @clnt: pointer to struct rpc_clnt
3084 * @xprtargs: pointer to struct xprt_create
3085 * @setup: callback to test and/or set up the connection
3086 * @data: pointer to setup function data
3087 *
3088 * Creates a new transport using the parameters set in args and
3089 * adds it to clnt.
3090 * If ping is set, then test that connectivity succeeds before
3091 * adding the new transport.
3092 *
3093 */
3094int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3095 struct xprt_create *xprtargs,
3096 int (*setup)(struct rpc_clnt *,
3097 struct rpc_xprt_switch *,
3098 struct rpc_xprt *,
3099 void *),
3100 void *data)
3101{
3102 struct rpc_xprt_switch *xps;
3103 struct rpc_xprt *xprt;
3104 unsigned long connect_timeout;
3105 unsigned long reconnect_timeout;
3106 unsigned char resvport, reuseport;
3107 int ret = 0, ident;
3108
3109 rcu_read_lock();
3110 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3111 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3112 if (xps == NULL || xprt == NULL) {
3113 rcu_read_unlock();
3114 xprt_switch_put(xps);
3115 return -EAGAIN;
3116 }
3117 resvport = xprt->resvport;
3118 reuseport = xprt->reuseport;
3119 connect_timeout = xprt->connect_timeout;
3120 reconnect_timeout = xprt->max_reconnect_timeout;
3121 ident = xprt->xprt_class->ident;
3122 rcu_read_unlock();
3123
3124 if (!xprtargs->ident)
3125 xprtargs->ident = ident;
3126 xprtargs->xprtsec = clnt->cl_xprtsec;
3127 xprt = xprt_create_transport(xprtargs);
3128 if (IS_ERR(xprt)) {
3129 ret = PTR_ERR(xprt);
3130 goto out_put_switch;
3131 }
3132 xprt->resvport = resvport;
3133 xprt->reuseport = reuseport;
3134
3135 if (xprtargs->connect_timeout)
3136 connect_timeout = xprtargs->connect_timeout;
3137 if (xprtargs->reconnect_timeout)
3138 reconnect_timeout = xprtargs->reconnect_timeout;
3139 if (xprt->ops->set_connect_timeout != NULL)
3140 xprt->ops->set_connect_timeout(xprt,
3141 connect_timeout,
3142 reconnect_timeout);
3143
3144 rpc_xprt_switch_set_roundrobin(xps);
3145 if (setup) {
3146 ret = setup(clnt, xps, xprt, data);
3147 if (ret != 0)
3148 goto out_put_xprt;
3149 }
3150 rpc_xprt_switch_add_xprt(xps, xprt);
3151out_put_xprt:
3152 xprt_put(xprt);
3153out_put_switch:
3154 xprt_switch_put(xps);
3155 return ret;
3156}
3157EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3158
3159static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3160 struct rpc_xprt *xprt,
3161 struct rpc_add_xprt_test *data)
3162{
3163 struct rpc_xprt *main_xprt;
3164 int status = 0;
3165
3166 xprt_get(xprt);
3167
3168 rcu_read_lock();
3169 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3170 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3171 (struct sockaddr *)&main_xprt->addr);
3172 rcu_read_unlock();
3173 xprt_put(main_xprt);
3174 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3175 goto out;
3176
3177 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3178out:
3179 xprt_put(xprt);
3180 return status;
3181}
3182
3183/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3184 * @clnt rpc_clnt structure
3185 *
3186 * For each offlined transport found in the rpc_clnt structure call
3187 * the function rpc_xprt_probe_trunked() which will determine if this
3188 * transport still belongs to the trunking group.
3189 */
3190void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3191 struct rpc_add_xprt_test *data)
3192{
3193 struct rpc_xprt_iter xpi;
3194 int ret;
3195
3196 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3197 if (ret)
3198 return;
3199 for (;;) {
3200 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3201
3202 if (!xprt)
3203 break;
3204 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3205 xprt_put(xprt);
3206 if (ret < 0)
3207 break;
3208 xprt_iter_rewind(&xpi);
3209 }
3210 xprt_iter_destroy(&xpi);
3211}
3212EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3213
3214static int rpc_xprt_offline(struct rpc_clnt *clnt,
3215 struct rpc_xprt *xprt,
3216 void *data)
3217{
3218 struct rpc_xprt *main_xprt;
3219 struct rpc_xprt_switch *xps;
3220 int err = 0;
3221
3222 xprt_get(xprt);
3223
3224 rcu_read_lock();
3225 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3226 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3227 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3228 (struct sockaddr *)&main_xprt->addr);
3229 rcu_read_unlock();
3230 xprt_put(main_xprt);
3231 if (err)
3232 goto out;
3233
3234 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3235 err = -EINTR;
3236 goto out;
3237 }
3238 xprt_set_offline_locked(xprt, xps);
3239
3240 xprt_release_write(xprt, NULL);
3241out:
3242 xprt_put(xprt);
3243 xprt_switch_put(xps);
3244 return err;
3245}
3246
3247/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3248 * @clnt rpc_clnt structure
3249 *
3250 * For each active transport found in the rpc_clnt structure call
3251 * the function rpc_xprt_offline() which will identify trunked transports
3252 * and will mark them offline.
3253 */
3254void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3255{
3256 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3257}
3258EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3259
3260struct connect_timeout_data {
3261 unsigned long connect_timeout;
3262 unsigned long reconnect_timeout;
3263};
3264
3265static int
3266rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3267 struct rpc_xprt *xprt,
3268 void *data)
3269{
3270 struct connect_timeout_data *timeo = data;
3271
3272 if (xprt->ops->set_connect_timeout)
3273 xprt->ops->set_connect_timeout(xprt,
3274 timeo->connect_timeout,
3275 timeo->reconnect_timeout);
3276 return 0;
3277}
3278
3279void
3280rpc_set_connect_timeout(struct rpc_clnt *clnt,
3281 unsigned long connect_timeout,
3282 unsigned long reconnect_timeout)
3283{
3284 struct connect_timeout_data timeout = {
3285 .connect_timeout = connect_timeout,
3286 .reconnect_timeout = reconnect_timeout,
3287 };
3288 rpc_clnt_iterate_for_each_xprt(clnt,
3289 rpc_xprt_set_connect_timeout,
3290 &timeout);
3291}
3292EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3293
3294void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3295{
3296 struct rpc_xprt_switch *xps;
3297
3298 xps = rpc_clnt_xprt_switch_get(clnt);
3299 xprt_set_online_locked(xprt, xps);
3300 xprt_switch_put(xps);
3301}
3302
3303void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3304{
3305 struct rpc_xprt_switch *xps;
3306
3307 if (rpc_clnt_xprt_switch_has_addr(clnt,
3308 (const struct sockaddr *)&xprt->addr)) {
3309 return rpc_clnt_xprt_set_online(clnt, xprt);
3310 }
3311
3312 xps = rpc_clnt_xprt_switch_get(clnt);
3313 rpc_xprt_switch_add_xprt(xps, xprt);
3314 xprt_switch_put(xps);
3315}
3316EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3317
3318void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3319{
3320 struct rpc_xprt_switch *xps;
3321
3322 rcu_read_lock();
3323 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3324 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3325 xprt, 0);
3326 xps->xps_nunique_destaddr_xprts--;
3327 rcu_read_unlock();
3328}
3329EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3330
3331bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3332 const struct sockaddr *sap)
3333{
3334 struct rpc_xprt_switch *xps;
3335 bool ret;
3336
3337 rcu_read_lock();
3338 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3339 ret = rpc_xprt_switch_has_addr(xps, sap);
3340 rcu_read_unlock();
3341 return ret;
3342}
3343EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3344
3345#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3346static void rpc_show_header(struct rpc_clnt *clnt)
3347{
3348 printk(KERN_INFO "clnt[%pISpc] RPC tasks[%d]\n",
3349 (struct sockaddr *)&clnt->cl_xprt->addr,
3350 atomic_read(&clnt->cl_task_count));
3351 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3352 "-timeout ---ops--\n");
3353}
3354
3355static void rpc_show_task(const struct rpc_clnt *clnt,
3356 const struct rpc_task *task)
3357{
3358 const char *rpc_waitq = "none";
3359
3360 if (RPC_IS_QUEUED(task))
3361 rpc_waitq = rpc_qname(task->tk_waitqueue);
3362
3363 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3364 task->tk_pid, task->tk_flags, task->tk_status,
3365 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3366 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3367 task->tk_action, rpc_waitq);
3368}
3369
3370void rpc_show_tasks(struct net *net)
3371{
3372 struct rpc_clnt *clnt;
3373 struct rpc_task *task;
3374 int header = 0;
3375 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3376
3377 spin_lock(&sn->rpc_client_lock);
3378 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3379 spin_lock(&clnt->cl_lock);
3380 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3381 if (!header) {
3382 rpc_show_header(clnt);
3383 header++;
3384 }
3385 rpc_show_task(clnt, task);
3386 }
3387 spin_unlock(&clnt->cl_lock);
3388 }
3389 spin_unlock(&sn->rpc_client_lock);
3390}
3391#endif
3392
3393#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3394static int
3395rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3396 struct rpc_xprt *xprt,
3397 void *dummy)
3398{
3399 return xprt_enable_swap(xprt);
3400}
3401
3402int
3403rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3404{
3405 while (clnt != clnt->cl_parent)
3406 clnt = clnt->cl_parent;
3407 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3408 return rpc_clnt_iterate_for_each_xprt(clnt,
3409 rpc_clnt_swap_activate_callback, NULL);
3410 return 0;
3411}
3412EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3413
3414static int
3415rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3416 struct rpc_xprt *xprt,
3417 void *dummy)
3418{
3419 xprt_disable_swap(xprt);
3420 return 0;
3421}
3422
3423void
3424rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3425{
3426 while (clnt != clnt->cl_parent)
3427 clnt = clnt->cl_parent;
3428 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3429 rpc_clnt_iterate_for_each_xprt(clnt,
3430 rpc_clnt_swap_deactivate_callback, NULL);
3431}
3432EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3433#endif /* CONFIG_SUNRPC_SWAP */
Linux 6.x block layer and io_uring tree(s)