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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.h>
29#include <linux/rcupdate.h>
30#include <linux/utsname.h>
31#include <linux/workqueue.h>
32#include <linux/in.h>
33#include <linux/in6.h>
34#include <linux/un.h>
35
36#include <linux/sunrpc/clnt.h>
37#include <linux/sunrpc/addr.h>
38#include <linux/sunrpc/rpc_pipe_fs.h>
39#include <linux/sunrpc/metrics.h>
40#include <linux/sunrpc/bc_xprt.h>
41#include <trace/events/sunrpc.h>
42
43#include "sunrpc.h"
44#include "sysfs.h"
45#include "netns.h"
46
47#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
48# define RPCDBG_FACILITY RPCDBG_CALL
49#endif
50
51/*
52 * All RPC clients are linked into this list
53 */
54
55static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
56
57
58static void call_start(struct rpc_task *task);
59static void call_reserve(struct rpc_task *task);
60static void call_reserveresult(struct rpc_task *task);
61static void call_allocate(struct rpc_task *task);
62static void call_encode(struct rpc_task *task);
63static void call_decode(struct rpc_task *task);
64static void call_bind(struct rpc_task *task);
65static void call_bind_status(struct rpc_task *task);
66static void call_transmit(struct rpc_task *task);
67static void call_status(struct rpc_task *task);
68static void call_transmit_status(struct rpc_task *task);
69static void call_refresh(struct rpc_task *task);
70static void call_refreshresult(struct rpc_task *task);
71static void call_connect(struct rpc_task *task);
72static void call_connect_status(struct rpc_task *task);
73
74static int rpc_encode_header(struct rpc_task *task,
75 struct xdr_stream *xdr);
76static int rpc_decode_header(struct rpc_task *task,
77 struct xdr_stream *xdr);
78static int rpc_ping(struct rpc_clnt *clnt);
79static int rpc_ping_noreply(struct rpc_clnt *clnt);
80static void rpc_check_timeout(struct rpc_task *task);
81
82static void rpc_register_client(struct rpc_clnt *clnt)
83{
84 struct net *net = rpc_net_ns(clnt);
85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
86
87 spin_lock(&sn->rpc_client_lock);
88 list_add(&clnt->cl_clients, &sn->all_clients);
89 spin_unlock(&sn->rpc_client_lock);
90}
91
92static void rpc_unregister_client(struct rpc_clnt *clnt)
93{
94 struct net *net = rpc_net_ns(clnt);
95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
96
97 spin_lock(&sn->rpc_client_lock);
98 list_del(&clnt->cl_clients);
99 spin_unlock(&sn->rpc_client_lock);
100}
101
102static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103{
104 rpc_remove_client_dir(clnt);
105}
106
107static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
108{
109 struct net *net = rpc_net_ns(clnt);
110 struct super_block *pipefs_sb;
111
112 pipefs_sb = rpc_get_sb_net(net);
113 if (pipefs_sb) {
114 if (pipefs_sb == clnt->pipefs_sb)
115 __rpc_clnt_remove_pipedir(clnt);
116 rpc_put_sb_net(net);
117 }
118}
119
120static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
121 struct rpc_clnt *clnt)
122{
123 static uint32_t clntid;
124 const char *dir_name = clnt->cl_program->pipe_dir_name;
125 char name[15];
126 struct dentry *dir, *dentry;
127
128 dir = rpc_d_lookup_sb(sb, dir_name);
129 if (dir == NULL) {
130 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
131 return dir;
132 }
133 for (;;) {
134 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
135 name[sizeof(name) - 1] = '\0';
136 dentry = rpc_create_client_dir(dir, name, clnt);
137 if (!IS_ERR(dentry))
138 break;
139 if (dentry == ERR_PTR(-EEXIST))
140 continue;
141 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
142 " %s/%s, error %ld\n",
143 dir_name, name, PTR_ERR(dentry));
144 break;
145 }
146 dput(dir);
147 return dentry;
148}
149
150static int
151rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
152{
153 struct dentry *dentry;
154
155 clnt->pipefs_sb = pipefs_sb;
156
157 if (clnt->cl_program->pipe_dir_name != NULL) {
158 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
159 if (IS_ERR(dentry))
160 return PTR_ERR(dentry);
161 }
162 return 0;
163}
164
165static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
166{
167 if (clnt->cl_program->pipe_dir_name == NULL)
168 return 1;
169
170 switch (event) {
171 case RPC_PIPEFS_MOUNT:
172 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
173 return 1;
174 if (refcount_read(&clnt->cl_count) == 0)
175 return 1;
176 break;
177 case RPC_PIPEFS_UMOUNT:
178 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
179 return 1;
180 break;
181 }
182 return 0;
183}
184
185static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
186 struct super_block *sb)
187{
188 struct dentry *dentry;
189
190 switch (event) {
191 case RPC_PIPEFS_MOUNT:
192 dentry = rpc_setup_pipedir_sb(sb, clnt);
193 if (!dentry)
194 return -ENOENT;
195 if (IS_ERR(dentry))
196 return PTR_ERR(dentry);
197 break;
198 case RPC_PIPEFS_UMOUNT:
199 __rpc_clnt_remove_pipedir(clnt);
200 break;
201 default:
202 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
203 return -ENOTSUPP;
204 }
205 return 0;
206}
207
208static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
209 struct super_block *sb)
210{
211 int error = 0;
212
213 for (;; clnt = clnt->cl_parent) {
214 if (!rpc_clnt_skip_event(clnt, event))
215 error = __rpc_clnt_handle_event(clnt, event, sb);
216 if (error || clnt == clnt->cl_parent)
217 break;
218 }
219 return error;
220}
221
222static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
223{
224 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
225 struct rpc_clnt *clnt;
226
227 spin_lock(&sn->rpc_client_lock);
228 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
229 if (rpc_clnt_skip_event(clnt, event))
230 continue;
231 spin_unlock(&sn->rpc_client_lock);
232 return clnt;
233 }
234 spin_unlock(&sn->rpc_client_lock);
235 return NULL;
236}
237
238static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
239 void *ptr)
240{
241 struct super_block *sb = ptr;
242 struct rpc_clnt *clnt;
243 int error = 0;
244
245 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
246 error = __rpc_pipefs_event(clnt, event, sb);
247 if (error)
248 break;
249 }
250 return error;
251}
252
253static struct notifier_block rpc_clients_block = {
254 .notifier_call = rpc_pipefs_event,
255 .priority = SUNRPC_PIPEFS_RPC_PRIO,
256};
257
258int rpc_clients_notifier_register(void)
259{
260 return rpc_pipefs_notifier_register(&rpc_clients_block);
261}
262
263void rpc_clients_notifier_unregister(void)
264{
265 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
266}
267
268static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
269 struct rpc_xprt *xprt,
270 const struct rpc_timeout *timeout)
271{
272 struct rpc_xprt *old;
273
274 spin_lock(&clnt->cl_lock);
275 old = rcu_dereference_protected(clnt->cl_xprt,
276 lockdep_is_held(&clnt->cl_lock));
277
278 if (!xprt_bound(xprt))
279 clnt->cl_autobind = 1;
280
281 clnt->cl_timeout = timeout;
282 rcu_assign_pointer(clnt->cl_xprt, xprt);
283 spin_unlock(&clnt->cl_lock);
284
285 return old;
286}
287
288static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
289{
290 ssize_t copied;
291
292 copied = strscpy(clnt->cl_nodename,
293 nodename, sizeof(clnt->cl_nodename));
294
295 clnt->cl_nodelen = copied < 0
296 ? sizeof(clnt->cl_nodename) - 1
297 : copied;
298}
299
300static int rpc_client_register(struct rpc_clnt *clnt,
301 rpc_authflavor_t pseudoflavor,
302 const char *client_name)
303{
304 struct rpc_auth_create_args auth_args = {
305 .pseudoflavor = pseudoflavor,
306 .target_name = client_name,
307 };
308 struct rpc_auth *auth;
309 struct net *net = rpc_net_ns(clnt);
310 struct super_block *pipefs_sb;
311 int err;
312
313 rpc_clnt_debugfs_register(clnt);
314
315 pipefs_sb = rpc_get_sb_net(net);
316 if (pipefs_sb) {
317 err = rpc_setup_pipedir(pipefs_sb, clnt);
318 if (err)
319 goto out;
320 }
321
322 rpc_register_client(clnt);
323 if (pipefs_sb)
324 rpc_put_sb_net(net);
325
326 auth = rpcauth_create(&auth_args, clnt);
327 if (IS_ERR(auth)) {
328 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
329 pseudoflavor);
330 err = PTR_ERR(auth);
331 goto err_auth;
332 }
333 return 0;
334err_auth:
335 pipefs_sb = rpc_get_sb_net(net);
336 rpc_unregister_client(clnt);
337 __rpc_clnt_remove_pipedir(clnt);
338out:
339 if (pipefs_sb)
340 rpc_put_sb_net(net);
341 rpc_sysfs_client_destroy(clnt);
342 rpc_clnt_debugfs_unregister(clnt);
343 return err;
344}
345
346static DEFINE_IDA(rpc_clids);
347
348void rpc_cleanup_clids(void)
349{
350 ida_destroy(&rpc_clids);
351}
352
353static int rpc_alloc_clid(struct rpc_clnt *clnt)
354{
355 int clid;
356
357 clid = ida_alloc(&rpc_clids, GFP_KERNEL);
358 if (clid < 0)
359 return clid;
360 clnt->cl_clid = clid;
361 return 0;
362}
363
364static void rpc_free_clid(struct rpc_clnt *clnt)
365{
366 ida_free(&rpc_clids, clnt->cl_clid);
367}
368
369static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
370 struct rpc_xprt_switch *xps,
371 struct rpc_xprt *xprt,
372 struct rpc_clnt *parent)
373{
374 const struct rpc_program *program = args->program;
375 const struct rpc_version *version;
376 struct rpc_clnt *clnt = NULL;
377 const struct rpc_timeout *timeout;
378 const char *nodename = args->nodename;
379 int err;
380
381 err = rpciod_up();
382 if (err)
383 goto out_no_rpciod;
384
385 err = -EINVAL;
386 if (args->version >= program->nrvers)
387 goto out_err;
388 version = program->version[args->version];
389 if (version == NULL)
390 goto out_err;
391
392 err = -ENOMEM;
393 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
394 if (!clnt)
395 goto out_err;
396 clnt->cl_parent = parent ? : clnt;
397 clnt->cl_xprtsec = args->xprtsec;
398
399 err = rpc_alloc_clid(clnt);
400 if (err)
401 goto out_no_clid;
402
403 clnt->cl_cred = get_cred(args->cred);
404 clnt->cl_procinfo = version->procs;
405 clnt->cl_maxproc = version->nrprocs;
406 clnt->cl_prog = args->prognumber ? : program->number;
407 clnt->cl_vers = version->number;
408 clnt->cl_stats = program->stats;
409 clnt->cl_metrics = rpc_alloc_iostats(clnt);
410 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
411 err = -ENOMEM;
412 if (clnt->cl_metrics == NULL)
413 goto out_no_stats;
414 clnt->cl_program = program;
415 INIT_LIST_HEAD(&clnt->cl_tasks);
416 spin_lock_init(&clnt->cl_lock);
417
418 timeout = xprt->timeout;
419 if (args->timeout != NULL) {
420 memcpy(&clnt->cl_timeout_default, args->timeout,
421 sizeof(clnt->cl_timeout_default));
422 timeout = &clnt->cl_timeout_default;
423 }
424
425 rpc_clnt_set_transport(clnt, xprt, timeout);
426 xprt->main = true;
427 xprt_iter_init(&clnt->cl_xpi, xps);
428 xprt_switch_put(xps);
429
430 clnt->cl_rtt = &clnt->cl_rtt_default;
431 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
432
433 refcount_set(&clnt->cl_count, 1);
434
435 if (nodename == NULL)
436 nodename = utsname()->nodename;
437 /* save the nodename */
438 rpc_clnt_set_nodename(clnt, nodename);
439
440 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
441 err = rpc_client_register(clnt, args->authflavor, args->client_name);
442 if (err)
443 goto out_no_path;
444 if (parent)
445 refcount_inc(&parent->cl_count);
446
447 trace_rpc_clnt_new(clnt, xprt, args);
448 return clnt;
449
450out_no_path:
451 rpc_free_iostats(clnt->cl_metrics);
452out_no_stats:
453 put_cred(clnt->cl_cred);
454 rpc_free_clid(clnt);
455out_no_clid:
456 kfree(clnt);
457out_err:
458 rpciod_down();
459out_no_rpciod:
460 xprt_switch_put(xps);
461 xprt_put(xprt);
462 trace_rpc_clnt_new_err(program->name, args->servername, err);
463 return ERR_PTR(err);
464}
465
466static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
467 struct rpc_xprt *xprt)
468{
469 struct rpc_clnt *clnt = NULL;
470 struct rpc_xprt_switch *xps;
471
472 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
473 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
474 xps = args->bc_xprt->xpt_bc_xps;
475 xprt_switch_get(xps);
476 } else {
477 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
478 if (xps == NULL) {
479 xprt_put(xprt);
480 return ERR_PTR(-ENOMEM);
481 }
482 if (xprt->bc_xprt) {
483 xprt_switch_get(xps);
484 xprt->bc_xprt->xpt_bc_xps = xps;
485 }
486 }
487 clnt = rpc_new_client(args, xps, xprt, NULL);
488 if (IS_ERR(clnt))
489 return clnt;
490
491 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
492 int err = rpc_ping(clnt);
493 if (err != 0) {
494 rpc_shutdown_client(clnt);
495 return ERR_PTR(err);
496 }
497 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
498 int err = rpc_ping_noreply(clnt);
499 if (err != 0) {
500 rpc_shutdown_client(clnt);
501 return ERR_PTR(err);
502 }
503 }
504
505 clnt->cl_softrtry = 1;
506 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
507 clnt->cl_softrtry = 0;
508 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
509 clnt->cl_softerr = 1;
510 }
511
512 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
513 clnt->cl_autobind = 1;
514 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
515 clnt->cl_noretranstimeo = 1;
516 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
517 clnt->cl_discrtry = 1;
518 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
519 clnt->cl_chatty = 1;
520
521 return clnt;
522}
523
524/**
525 * rpc_create - create an RPC client and transport with one call
526 * @args: rpc_clnt create argument structure
527 *
528 * Creates and initializes an RPC transport and an RPC client.
529 *
530 * It can ping the server in order to determine if it is up, and to see if
531 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
532 * this behavior so asynchronous tasks can also use rpc_create.
533 */
534struct rpc_clnt *rpc_create(struct rpc_create_args *args)
535{
536 struct rpc_xprt *xprt;
537 struct xprt_create xprtargs = {
538 .net = args->net,
539 .ident = args->protocol,
540 .srcaddr = args->saddress,
541 .dstaddr = args->address,
542 .addrlen = args->addrsize,
543 .servername = args->servername,
544 .bc_xprt = args->bc_xprt,
545 .xprtsec = args->xprtsec,
546 .connect_timeout = args->connect_timeout,
547 .reconnect_timeout = args->reconnect_timeout,
548 };
549 char servername[48];
550 struct rpc_clnt *clnt;
551 int i;
552
553 if (args->bc_xprt) {
554 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
555 xprt = args->bc_xprt->xpt_bc_xprt;
556 if (xprt) {
557 xprt_get(xprt);
558 return rpc_create_xprt(args, xprt);
559 }
560 }
561
562 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
563 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
564 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
565 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
566 /*
567 * If the caller chooses not to specify a hostname, whip
568 * up a string representation of the passed-in address.
569 */
570 if (xprtargs.servername == NULL) {
571 struct sockaddr_un *sun =
572 (struct sockaddr_un *)args->address;
573 struct sockaddr_in *sin =
574 (struct sockaddr_in *)args->address;
575 struct sockaddr_in6 *sin6 =
576 (struct sockaddr_in6 *)args->address;
577
578 servername[0] = '\0';
579 switch (args->address->sa_family) {
580 case AF_LOCAL:
581 if (sun->sun_path[0])
582 snprintf(servername, sizeof(servername), "%s",
583 sun->sun_path);
584 else
585 snprintf(servername, sizeof(servername), "@%s",
586 sun->sun_path+1);
587 break;
588 case AF_INET:
589 snprintf(servername, sizeof(servername), "%pI4",
590 &sin->sin_addr.s_addr);
591 break;
592 case AF_INET6:
593 snprintf(servername, sizeof(servername), "%pI6",
594 &sin6->sin6_addr);
595 break;
596 default:
597 /* caller wants default server name, but
598 * address family isn't recognized. */
599 return ERR_PTR(-EINVAL);
600 }
601 xprtargs.servername = servername;
602 }
603
604 xprt = xprt_create_transport(&xprtargs);
605 if (IS_ERR(xprt))
606 return (struct rpc_clnt *)xprt;
607
608 /*
609 * By default, kernel RPC client connects from a reserved port.
610 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
611 * but it is always enabled for rpciod, which handles the connect
612 * operation.
613 */
614 xprt->resvport = 1;
615 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
616 xprt->resvport = 0;
617 xprt->reuseport = 0;
618 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
619 xprt->reuseport = 1;
620
621 clnt = rpc_create_xprt(args, xprt);
622 if (IS_ERR(clnt) || args->nconnect <= 1)
623 return clnt;
624
625 for (i = 0; i < args->nconnect - 1; i++) {
626 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
627 break;
628 }
629 return clnt;
630}
631EXPORT_SYMBOL_GPL(rpc_create);
632
633/*
634 * This function clones the RPC client structure. It allows us to share the
635 * same transport while varying parameters such as the authentication
636 * flavour.
637 */
638static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
639 struct rpc_clnt *clnt)
640{
641 struct rpc_xprt_switch *xps;
642 struct rpc_xprt *xprt;
643 struct rpc_clnt *new;
644 int err;
645
646 err = -ENOMEM;
647 rcu_read_lock();
648 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
649 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
650 rcu_read_unlock();
651 if (xprt == NULL || xps == NULL) {
652 xprt_put(xprt);
653 xprt_switch_put(xps);
654 goto out_err;
655 }
656 args->servername = xprt->servername;
657 args->nodename = clnt->cl_nodename;
658
659 new = rpc_new_client(args, xps, xprt, clnt);
660 if (IS_ERR(new))
661 return new;
662
663 /* Turn off autobind on clones */
664 new->cl_autobind = 0;
665 new->cl_softrtry = clnt->cl_softrtry;
666 new->cl_softerr = clnt->cl_softerr;
667 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
668 new->cl_discrtry = clnt->cl_discrtry;
669 new->cl_chatty = clnt->cl_chatty;
670 new->cl_principal = clnt->cl_principal;
671 new->cl_max_connect = clnt->cl_max_connect;
672 return new;
673
674out_err:
675 trace_rpc_clnt_clone_err(clnt, err);
676 return ERR_PTR(err);
677}
678
679/**
680 * rpc_clone_client - Clone an RPC client structure
681 *
682 * @clnt: RPC client whose parameters are copied
683 *
684 * Returns a fresh RPC client or an ERR_PTR.
685 */
686struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
687{
688 struct rpc_create_args args = {
689 .program = clnt->cl_program,
690 .prognumber = clnt->cl_prog,
691 .version = clnt->cl_vers,
692 .authflavor = clnt->cl_auth->au_flavor,
693 .cred = clnt->cl_cred,
694 };
695 return __rpc_clone_client(&args, clnt);
696}
697EXPORT_SYMBOL_GPL(rpc_clone_client);
698
699/**
700 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
701 *
702 * @clnt: RPC client whose parameters are copied
703 * @flavor: security flavor for new client
704 *
705 * Returns a fresh RPC client or an ERR_PTR.
706 */
707struct rpc_clnt *
708rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
709{
710 struct rpc_create_args args = {
711 .program = clnt->cl_program,
712 .prognumber = clnt->cl_prog,
713 .version = clnt->cl_vers,
714 .authflavor = flavor,
715 .cred = clnt->cl_cred,
716 };
717 return __rpc_clone_client(&args, clnt);
718}
719EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
720
721/**
722 * rpc_switch_client_transport: switch the RPC transport on the fly
723 * @clnt: pointer to a struct rpc_clnt
724 * @args: pointer to the new transport arguments
725 * @timeout: pointer to the new timeout parameters
726 *
727 * This function allows the caller to switch the RPC transport for the
728 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
729 * server, for instance. It assumes that the caller has ensured that
730 * there are no active RPC tasks by using some form of locking.
731 *
732 * Returns zero if "clnt" is now using the new xprt. Otherwise a
733 * negative errno is returned, and "clnt" continues to use the old
734 * xprt.
735 */
736int rpc_switch_client_transport(struct rpc_clnt *clnt,
737 struct xprt_create *args,
738 const struct rpc_timeout *timeout)
739{
740 const struct rpc_timeout *old_timeo;
741 rpc_authflavor_t pseudoflavor;
742 struct rpc_xprt_switch *xps, *oldxps;
743 struct rpc_xprt *xprt, *old;
744 struct rpc_clnt *parent;
745 int err;
746
747 args->xprtsec = clnt->cl_xprtsec;
748 xprt = xprt_create_transport(args);
749 if (IS_ERR(xprt))
750 return PTR_ERR(xprt);
751
752 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
753 if (xps == NULL) {
754 xprt_put(xprt);
755 return -ENOMEM;
756 }
757
758 pseudoflavor = clnt->cl_auth->au_flavor;
759
760 old_timeo = clnt->cl_timeout;
761 old = rpc_clnt_set_transport(clnt, xprt, timeout);
762 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
763
764 rpc_unregister_client(clnt);
765 __rpc_clnt_remove_pipedir(clnt);
766 rpc_sysfs_client_destroy(clnt);
767 rpc_clnt_debugfs_unregister(clnt);
768
769 /*
770 * A new transport was created. "clnt" therefore
771 * becomes the root of a new cl_parent tree. clnt's
772 * children, if it has any, still point to the old xprt.
773 */
774 parent = clnt->cl_parent;
775 clnt->cl_parent = clnt;
776
777 /*
778 * The old rpc_auth cache cannot be re-used. GSS
779 * contexts in particular are between a single
780 * client and server.
781 */
782 err = rpc_client_register(clnt, pseudoflavor, NULL);
783 if (err)
784 goto out_revert;
785
786 synchronize_rcu();
787 if (parent != clnt)
788 rpc_release_client(parent);
789 xprt_switch_put(oldxps);
790 xprt_put(old);
791 trace_rpc_clnt_replace_xprt(clnt);
792 return 0;
793
794out_revert:
795 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
796 rpc_clnt_set_transport(clnt, old, old_timeo);
797 clnt->cl_parent = parent;
798 rpc_client_register(clnt, pseudoflavor, NULL);
799 xprt_switch_put(xps);
800 xprt_put(xprt);
801 trace_rpc_clnt_replace_xprt_err(clnt);
802 return err;
803}
804EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
805
806static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt)
807{
808 struct rpc_xprt_switch *xps;
809
810 rcu_read_lock();
811 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
812 rcu_read_unlock();
813
814 return xps;
815}
816
817static
818int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
819 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
820{
821 struct rpc_xprt_switch *xps;
822
823 xps = rpc_clnt_xprt_switch_get(clnt);
824 if (xps == NULL)
825 return -EAGAIN;
826 func(xpi, xps);
827 xprt_switch_put(xps);
828 return 0;
829}
830
831static
832int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
833{
834 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
835}
836
837static
838int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
839 struct rpc_xprt_iter *xpi)
840{
841 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
842}
843
844/**
845 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
846 * @clnt: pointer to client
847 * @fn: function to apply
848 * @data: void pointer to function data
849 *
850 * Iterates through the list of RPC transports currently attached to the
851 * client and applies the function fn(clnt, xprt, data).
852 *
853 * On error, the iteration stops, and the function returns the error value.
854 */
855int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
856 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
857 void *data)
858{
859 struct rpc_xprt_iter xpi;
860 int ret;
861
862 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
863 if (ret)
864 return ret;
865 for (;;) {
866 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
867
868 if (!xprt)
869 break;
870 ret = fn(clnt, xprt, data);
871 xprt_put(xprt);
872 if (ret < 0)
873 break;
874 }
875 xprt_iter_destroy(&xpi);
876 return ret;
877}
878EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
879
880/*
881 * Kill all tasks for the given client.
882 * XXX: kill their descendants as well?
883 */
884void rpc_killall_tasks(struct rpc_clnt *clnt)
885{
886 struct rpc_task *rovr;
887
888
889 if (list_empty(&clnt->cl_tasks))
890 return;
891
892 /*
893 * Spin lock all_tasks to prevent changes...
894 */
895 trace_rpc_clnt_killall(clnt);
896 spin_lock(&clnt->cl_lock);
897 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
898 rpc_signal_task(rovr);
899 spin_unlock(&clnt->cl_lock);
900}
901EXPORT_SYMBOL_GPL(rpc_killall_tasks);
902
903/**
904 * rpc_cancel_tasks - try to cancel a set of RPC tasks
905 * @clnt: Pointer to RPC client
906 * @error: RPC task error value to set
907 * @fnmatch: Pointer to selector function
908 * @data: User data
909 *
910 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
911 * The argument @error must be a negative error value.
912 */
913unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
914 bool (*fnmatch)(const struct rpc_task *,
915 const void *),
916 const void *data)
917{
918 struct rpc_task *task;
919 unsigned long count = 0;
920
921 if (list_empty(&clnt->cl_tasks))
922 return 0;
923 /*
924 * Spin lock all_tasks to prevent changes...
925 */
926 spin_lock(&clnt->cl_lock);
927 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
928 if (!RPC_IS_ACTIVATED(task))
929 continue;
930 if (!fnmatch(task, data))
931 continue;
932 rpc_task_try_cancel(task, error);
933 count++;
934 }
935 spin_unlock(&clnt->cl_lock);
936 return count;
937}
938EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
939
940static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
941 struct rpc_xprt *xprt, void *dummy)
942{
943 if (xprt_connected(xprt))
944 xprt_force_disconnect(xprt);
945 return 0;
946}
947
948void rpc_clnt_disconnect(struct rpc_clnt *clnt)
949{
950 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
951}
952EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
953
954/*
955 * Properly shut down an RPC client, terminating all outstanding
956 * requests.
957 */
958void rpc_shutdown_client(struct rpc_clnt *clnt)
959{
960 might_sleep();
961
962 trace_rpc_clnt_shutdown(clnt);
963
964 while (!list_empty(&clnt->cl_tasks)) {
965 rpc_killall_tasks(clnt);
966 wait_event_timeout(destroy_wait,
967 list_empty(&clnt->cl_tasks), 1*HZ);
968 }
969
970 rpc_release_client(clnt);
971}
972EXPORT_SYMBOL_GPL(rpc_shutdown_client);
973
974/*
975 * Free an RPC client
976 */
977static void rpc_free_client_work(struct work_struct *work)
978{
979 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
980
981 trace_rpc_clnt_free(clnt);
982
983 /* These might block on processes that might allocate memory,
984 * so they cannot be called in rpciod, so they are handled separately
985 * here.
986 */
987 rpc_sysfs_client_destroy(clnt);
988 rpc_clnt_debugfs_unregister(clnt);
989 rpc_free_clid(clnt);
990 rpc_clnt_remove_pipedir(clnt);
991 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
992
993 kfree(clnt);
994 rpciod_down();
995}
996static struct rpc_clnt *
997rpc_free_client(struct rpc_clnt *clnt)
998{
999 struct rpc_clnt *parent = NULL;
1000
1001 trace_rpc_clnt_release(clnt);
1002 if (clnt->cl_parent != clnt)
1003 parent = clnt->cl_parent;
1004 rpc_unregister_client(clnt);
1005 rpc_free_iostats(clnt->cl_metrics);
1006 clnt->cl_metrics = NULL;
1007 xprt_iter_destroy(&clnt->cl_xpi);
1008 put_cred(clnt->cl_cred);
1009
1010 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
1011 schedule_work(&clnt->cl_work);
1012 return parent;
1013}
1014
1015/*
1016 * Free an RPC client
1017 */
1018static struct rpc_clnt *
1019rpc_free_auth(struct rpc_clnt *clnt)
1020{
1021 /*
1022 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
1023 * release remaining GSS contexts. This mechanism ensures
1024 * that it can do so safely.
1025 */
1026 if (clnt->cl_auth != NULL) {
1027 rpcauth_release(clnt->cl_auth);
1028 clnt->cl_auth = NULL;
1029 }
1030 if (refcount_dec_and_test(&clnt->cl_count))
1031 return rpc_free_client(clnt);
1032 return NULL;
1033}
1034
1035/*
1036 * Release reference to the RPC client
1037 */
1038void
1039rpc_release_client(struct rpc_clnt *clnt)
1040{
1041 do {
1042 if (list_empty(&clnt->cl_tasks))
1043 wake_up(&destroy_wait);
1044 if (refcount_dec_not_one(&clnt->cl_count))
1045 break;
1046 clnt = rpc_free_auth(clnt);
1047 } while (clnt != NULL);
1048}
1049EXPORT_SYMBOL_GPL(rpc_release_client);
1050
1051/**
1052 * rpc_bind_new_program - bind a new RPC program to an existing client
1053 * @old: old rpc_client
1054 * @program: rpc program to set
1055 * @vers: rpc program version
1056 *
1057 * Clones the rpc client and sets up a new RPC program. This is mainly
1058 * of use for enabling different RPC programs to share the same transport.
1059 * The Sun NFSv2/v3 ACL protocol can do this.
1060 */
1061struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1062 const struct rpc_program *program,
1063 u32 vers)
1064{
1065 struct rpc_create_args args = {
1066 .program = program,
1067 .prognumber = program->number,
1068 .version = vers,
1069 .authflavor = old->cl_auth->au_flavor,
1070 .cred = old->cl_cred,
1071 };
1072 struct rpc_clnt *clnt;
1073 int err;
1074
1075 clnt = __rpc_clone_client(&args, old);
1076 if (IS_ERR(clnt))
1077 goto out;
1078 err = rpc_ping(clnt);
1079 if (err != 0) {
1080 rpc_shutdown_client(clnt);
1081 clnt = ERR_PTR(err);
1082 }
1083out:
1084 return clnt;
1085}
1086EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1087
1088struct rpc_xprt *
1089rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1090{
1091 struct rpc_xprt_switch *xps;
1092
1093 if (!xprt)
1094 return NULL;
1095 rcu_read_lock();
1096 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1097 atomic_long_inc(&xps->xps_queuelen);
1098 rcu_read_unlock();
1099 atomic_long_inc(&xprt->queuelen);
1100
1101 return xprt;
1102}
1103
1104static void
1105rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1106{
1107 struct rpc_xprt_switch *xps;
1108
1109 atomic_long_dec(&xprt->queuelen);
1110 rcu_read_lock();
1111 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1112 atomic_long_dec(&xps->xps_queuelen);
1113 rcu_read_unlock();
1114
1115 xprt_put(xprt);
1116}
1117
1118void rpc_task_release_transport(struct rpc_task *task)
1119{
1120 struct rpc_xprt *xprt = task->tk_xprt;
1121
1122 if (xprt) {
1123 task->tk_xprt = NULL;
1124 if (task->tk_client)
1125 rpc_task_release_xprt(task->tk_client, xprt);
1126 else
1127 xprt_put(xprt);
1128 }
1129}
1130EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1131
1132void rpc_task_release_client(struct rpc_task *task)
1133{
1134 struct rpc_clnt *clnt = task->tk_client;
1135
1136 rpc_task_release_transport(task);
1137 if (clnt != NULL) {
1138 /* Remove from client task list */
1139 spin_lock(&clnt->cl_lock);
1140 list_del(&task->tk_task);
1141 spin_unlock(&clnt->cl_lock);
1142 task->tk_client = NULL;
1143
1144 rpc_release_client(clnt);
1145 }
1146}
1147
1148static struct rpc_xprt *
1149rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1150{
1151 struct rpc_xprt *xprt;
1152
1153 rcu_read_lock();
1154 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1155 rcu_read_unlock();
1156 return rpc_task_get_xprt(clnt, xprt);
1157}
1158
1159static struct rpc_xprt *
1160rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1161{
1162 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1163}
1164
1165static
1166void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1167{
1168 if (task->tk_xprt) {
1169 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1170 (task->tk_flags & RPC_TASK_MOVEABLE)))
1171 return;
1172 xprt_release(task);
1173 xprt_put(task->tk_xprt);
1174 }
1175 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1176 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1177 else
1178 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1179}
1180
1181static
1182void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1183{
1184 rpc_task_set_transport(task, clnt);
1185 task->tk_client = clnt;
1186 refcount_inc(&clnt->cl_count);
1187 if (clnt->cl_softrtry)
1188 task->tk_flags |= RPC_TASK_SOFT;
1189 if (clnt->cl_softerr)
1190 task->tk_flags |= RPC_TASK_TIMEOUT;
1191 if (clnt->cl_noretranstimeo)
1192 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1193 /* Add to the client's list of all tasks */
1194 spin_lock(&clnt->cl_lock);
1195 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1196 spin_unlock(&clnt->cl_lock);
1197}
1198
1199static void
1200rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1201{
1202 if (msg != NULL) {
1203 task->tk_msg.rpc_proc = msg->rpc_proc;
1204 task->tk_msg.rpc_argp = msg->rpc_argp;
1205 task->tk_msg.rpc_resp = msg->rpc_resp;
1206 task->tk_msg.rpc_cred = msg->rpc_cred;
1207 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1208 get_cred(task->tk_msg.rpc_cred);
1209 }
1210}
1211
1212/*
1213 * Default callback for async RPC calls
1214 */
1215static void
1216rpc_default_callback(struct rpc_task *task, void *data)
1217{
1218}
1219
1220static const struct rpc_call_ops rpc_default_ops = {
1221 .rpc_call_done = rpc_default_callback,
1222};
1223
1224/**
1225 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1226 * @task_setup_data: pointer to task initialisation data
1227 */
1228struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1229{
1230 struct rpc_task *task;
1231
1232 task = rpc_new_task(task_setup_data);
1233 if (IS_ERR(task))
1234 return task;
1235
1236 if (!RPC_IS_ASYNC(task))
1237 task->tk_flags |= RPC_TASK_CRED_NOREF;
1238
1239 rpc_task_set_client(task, task_setup_data->rpc_client);
1240 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1241
1242 if (task->tk_action == NULL)
1243 rpc_call_start(task);
1244
1245 atomic_inc(&task->tk_count);
1246 rpc_execute(task);
1247 return task;
1248}
1249EXPORT_SYMBOL_GPL(rpc_run_task);
1250
1251/**
1252 * rpc_call_sync - Perform a synchronous RPC call
1253 * @clnt: pointer to RPC client
1254 * @msg: RPC call parameters
1255 * @flags: RPC call flags
1256 */
1257int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1258{
1259 struct rpc_task *task;
1260 struct rpc_task_setup task_setup_data = {
1261 .rpc_client = clnt,
1262 .rpc_message = msg,
1263 .callback_ops = &rpc_default_ops,
1264 .flags = flags,
1265 };
1266 int status;
1267
1268 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1269 if (flags & RPC_TASK_ASYNC) {
1270 rpc_release_calldata(task_setup_data.callback_ops,
1271 task_setup_data.callback_data);
1272 return -EINVAL;
1273 }
1274
1275 task = rpc_run_task(&task_setup_data);
1276 if (IS_ERR(task))
1277 return PTR_ERR(task);
1278 status = task->tk_status;
1279 rpc_put_task(task);
1280 return status;
1281}
1282EXPORT_SYMBOL_GPL(rpc_call_sync);
1283
1284/**
1285 * rpc_call_async - Perform an asynchronous RPC call
1286 * @clnt: pointer to RPC client
1287 * @msg: RPC call parameters
1288 * @flags: RPC call flags
1289 * @tk_ops: RPC call ops
1290 * @data: user call data
1291 */
1292int
1293rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1294 const struct rpc_call_ops *tk_ops, void *data)
1295{
1296 struct rpc_task *task;
1297 struct rpc_task_setup task_setup_data = {
1298 .rpc_client = clnt,
1299 .rpc_message = msg,
1300 .callback_ops = tk_ops,
1301 .callback_data = data,
1302 .flags = flags|RPC_TASK_ASYNC,
1303 };
1304
1305 task = rpc_run_task(&task_setup_data);
1306 if (IS_ERR(task))
1307 return PTR_ERR(task);
1308 rpc_put_task(task);
1309 return 0;
1310}
1311EXPORT_SYMBOL_GPL(rpc_call_async);
1312
1313#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1314static void call_bc_encode(struct rpc_task *task);
1315
1316/**
1317 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1318 * rpc_execute against it
1319 * @req: RPC request
1320 * @timeout: timeout values to use for this task
1321 */
1322struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1323 struct rpc_timeout *timeout)
1324{
1325 struct rpc_task *task;
1326 struct rpc_task_setup task_setup_data = {
1327 .callback_ops = &rpc_default_ops,
1328 .flags = RPC_TASK_SOFTCONN |
1329 RPC_TASK_NO_RETRANS_TIMEOUT,
1330 };
1331
1332 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1333 /*
1334 * Create an rpc_task to send the data
1335 */
1336 task = rpc_new_task(&task_setup_data);
1337 if (IS_ERR(task)) {
1338 xprt_free_bc_request(req);
1339 return task;
1340 }
1341
1342 xprt_init_bc_request(req, task, timeout);
1343
1344 task->tk_action = call_bc_encode;
1345 atomic_inc(&task->tk_count);
1346 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1347 rpc_execute(task);
1348
1349 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1350 return task;
1351}
1352#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1353
1354/**
1355 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1356 * @req: RPC request to prepare
1357 * @pages: vector of struct page pointers
1358 * @base: offset in first page where receive should start, in bytes
1359 * @len: expected size of the upper layer data payload, in bytes
1360 * @hdrsize: expected size of upper layer reply header, in XDR words
1361 *
1362 */
1363void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1364 unsigned int base, unsigned int len,
1365 unsigned int hdrsize)
1366{
1367 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1368
1369 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1370 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1371}
1372EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1373
1374void
1375rpc_call_start(struct rpc_task *task)
1376{
1377 task->tk_action = call_start;
1378}
1379EXPORT_SYMBOL_GPL(rpc_call_start);
1380
1381/**
1382 * rpc_peeraddr - extract remote peer address from clnt's xprt
1383 * @clnt: RPC client structure
1384 * @buf: target buffer
1385 * @bufsize: length of target buffer
1386 *
1387 * Returns the number of bytes that are actually in the stored address.
1388 */
1389size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1390{
1391 size_t bytes;
1392 struct rpc_xprt *xprt;
1393
1394 rcu_read_lock();
1395 xprt = rcu_dereference(clnt->cl_xprt);
1396
1397 bytes = xprt->addrlen;
1398 if (bytes > bufsize)
1399 bytes = bufsize;
1400 memcpy(buf, &xprt->addr, bytes);
1401 rcu_read_unlock();
1402
1403 return bytes;
1404}
1405EXPORT_SYMBOL_GPL(rpc_peeraddr);
1406
1407/**
1408 * rpc_peeraddr2str - return remote peer address in printable format
1409 * @clnt: RPC client structure
1410 * @format: address format
1411 *
1412 * NB: the lifetime of the memory referenced by the returned pointer is
1413 * the same as the rpc_xprt itself. As long as the caller uses this
1414 * pointer, it must hold the RCU read lock.
1415 */
1416const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1417 enum rpc_display_format_t format)
1418{
1419 struct rpc_xprt *xprt;
1420
1421 xprt = rcu_dereference(clnt->cl_xprt);
1422
1423 if (xprt->address_strings[format] != NULL)
1424 return xprt->address_strings[format];
1425 else
1426 return "unprintable";
1427}
1428EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1429
1430static const struct sockaddr_in rpc_inaddr_loopback = {
1431 .sin_family = AF_INET,
1432 .sin_addr.s_addr = htonl(INADDR_ANY),
1433};
1434
1435static const struct sockaddr_in6 rpc_in6addr_loopback = {
1436 .sin6_family = AF_INET6,
1437 .sin6_addr = IN6ADDR_ANY_INIT,
1438};
1439
1440/*
1441 * Try a getsockname() on a connected datagram socket. Using a
1442 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1443 * This conserves the ephemeral port number space.
1444 *
1445 * Returns zero and fills in "buf" if successful; otherwise, a
1446 * negative errno is returned.
1447 */
1448static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1449 struct sockaddr *buf)
1450{
1451 struct socket *sock;
1452 int err;
1453
1454 err = __sock_create(net, sap->sa_family,
1455 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1456 if (err < 0) {
1457 dprintk("RPC: can't create UDP socket (%d)\n", err);
1458 goto out;
1459 }
1460
1461 switch (sap->sa_family) {
1462 case AF_INET:
1463 err = kernel_bind(sock,
1464 (struct sockaddr *)&rpc_inaddr_loopback,
1465 sizeof(rpc_inaddr_loopback));
1466 break;
1467 case AF_INET6:
1468 err = kernel_bind(sock,
1469 (struct sockaddr *)&rpc_in6addr_loopback,
1470 sizeof(rpc_in6addr_loopback));
1471 break;
1472 default:
1473 err = -EAFNOSUPPORT;
1474 goto out_release;
1475 }
1476 if (err < 0) {
1477 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1478 goto out_release;
1479 }
1480
1481 err = kernel_connect(sock, sap, salen, 0);
1482 if (err < 0) {
1483 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1484 goto out_release;
1485 }
1486
1487 err = kernel_getsockname(sock, buf);
1488 if (err < 0) {
1489 dprintk("RPC: getsockname failed (%d)\n", err);
1490 goto out_release;
1491 }
1492
1493 err = 0;
1494 if (buf->sa_family == AF_INET6) {
1495 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1496 sin6->sin6_scope_id = 0;
1497 }
1498 dprintk("RPC: %s succeeded\n", __func__);
1499
1500out_release:
1501 sock_release(sock);
1502out:
1503 return err;
1504}
1505
1506/*
1507 * Scraping a connected socket failed, so we don't have a useable
1508 * local address. Fallback: generate an address that will prevent
1509 * the server from calling us back.
1510 *
1511 * Returns zero and fills in "buf" if successful; otherwise, a
1512 * negative errno is returned.
1513 */
1514static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1515{
1516 switch (family) {
1517 case AF_INET:
1518 if (buflen < sizeof(rpc_inaddr_loopback))
1519 return -EINVAL;
1520 memcpy(buf, &rpc_inaddr_loopback,
1521 sizeof(rpc_inaddr_loopback));
1522 break;
1523 case AF_INET6:
1524 if (buflen < sizeof(rpc_in6addr_loopback))
1525 return -EINVAL;
1526 memcpy(buf, &rpc_in6addr_loopback,
1527 sizeof(rpc_in6addr_loopback));
1528 break;
1529 default:
1530 dprintk("RPC: %s: address family not supported\n",
1531 __func__);
1532 return -EAFNOSUPPORT;
1533 }
1534 dprintk("RPC: %s: succeeded\n", __func__);
1535 return 0;
1536}
1537
1538/**
1539 * rpc_localaddr - discover local endpoint address for an RPC client
1540 * @clnt: RPC client structure
1541 * @buf: target buffer
1542 * @buflen: size of target buffer, in bytes
1543 *
1544 * Returns zero and fills in "buf" and "buflen" if successful;
1545 * otherwise, a negative errno is returned.
1546 *
1547 * This works even if the underlying transport is not currently connected,
1548 * or if the upper layer never previously provided a source address.
1549 *
1550 * The result of this function call is transient: multiple calls in
1551 * succession may give different results, depending on how local
1552 * networking configuration changes over time.
1553 */
1554int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1555{
1556 struct sockaddr_storage address;
1557 struct sockaddr *sap = (struct sockaddr *)&address;
1558 struct rpc_xprt *xprt;
1559 struct net *net;
1560 size_t salen;
1561 int err;
1562
1563 rcu_read_lock();
1564 xprt = rcu_dereference(clnt->cl_xprt);
1565 salen = xprt->addrlen;
1566 memcpy(sap, &xprt->addr, salen);
1567 net = get_net(xprt->xprt_net);
1568 rcu_read_unlock();
1569
1570 rpc_set_port(sap, 0);
1571 err = rpc_sockname(net, sap, salen, buf);
1572 put_net(net);
1573 if (err != 0)
1574 /* Couldn't discover local address, return ANYADDR */
1575 return rpc_anyaddr(sap->sa_family, buf, buflen);
1576 return 0;
1577}
1578EXPORT_SYMBOL_GPL(rpc_localaddr);
1579
1580void
1581rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1582{
1583 struct rpc_xprt *xprt;
1584
1585 rcu_read_lock();
1586 xprt = rcu_dereference(clnt->cl_xprt);
1587 if (xprt->ops->set_buffer_size)
1588 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1589 rcu_read_unlock();
1590}
1591EXPORT_SYMBOL_GPL(rpc_setbufsize);
1592
1593/**
1594 * rpc_net_ns - Get the network namespace for this RPC client
1595 * @clnt: RPC client to query
1596 *
1597 */
1598struct net *rpc_net_ns(struct rpc_clnt *clnt)
1599{
1600 struct net *ret;
1601
1602 rcu_read_lock();
1603 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1604 rcu_read_unlock();
1605 return ret;
1606}
1607EXPORT_SYMBOL_GPL(rpc_net_ns);
1608
1609/**
1610 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1611 * @clnt: RPC client to query
1612 *
1613 * For stream transports, this is one RPC record fragment (see RFC
1614 * 1831), as we don't support multi-record requests yet. For datagram
1615 * transports, this is the size of an IP packet minus the IP, UDP, and
1616 * RPC header sizes.
1617 */
1618size_t rpc_max_payload(struct rpc_clnt *clnt)
1619{
1620 size_t ret;
1621
1622 rcu_read_lock();
1623 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1624 rcu_read_unlock();
1625 return ret;
1626}
1627EXPORT_SYMBOL_GPL(rpc_max_payload);
1628
1629/**
1630 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1631 * @clnt: RPC client to query
1632 */
1633size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1634{
1635 struct rpc_xprt *xprt;
1636 size_t ret;
1637
1638 rcu_read_lock();
1639 xprt = rcu_dereference(clnt->cl_xprt);
1640 ret = xprt->ops->bc_maxpayload(xprt);
1641 rcu_read_unlock();
1642 return ret;
1643}
1644EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1645
1646unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1647{
1648 struct rpc_xprt *xprt;
1649 unsigned int ret;
1650
1651 rcu_read_lock();
1652 xprt = rcu_dereference(clnt->cl_xprt);
1653 ret = xprt->ops->bc_num_slots(xprt);
1654 rcu_read_unlock();
1655 return ret;
1656}
1657EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1658
1659/**
1660 * rpc_force_rebind - force transport to check that remote port is unchanged
1661 * @clnt: client to rebind
1662 *
1663 */
1664void rpc_force_rebind(struct rpc_clnt *clnt)
1665{
1666 if (clnt->cl_autobind) {
1667 rcu_read_lock();
1668 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1669 rcu_read_unlock();
1670 }
1671}
1672EXPORT_SYMBOL_GPL(rpc_force_rebind);
1673
1674static int
1675__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1676{
1677 task->tk_status = 0;
1678 task->tk_rpc_status = 0;
1679 task->tk_action = action;
1680 return 1;
1681}
1682
1683/*
1684 * Restart an (async) RPC call. Usually called from within the
1685 * exit handler.
1686 */
1687int
1688rpc_restart_call(struct rpc_task *task)
1689{
1690 return __rpc_restart_call(task, call_start);
1691}
1692EXPORT_SYMBOL_GPL(rpc_restart_call);
1693
1694/*
1695 * Restart an (async) RPC call from the call_prepare state.
1696 * Usually called from within the exit handler.
1697 */
1698int
1699rpc_restart_call_prepare(struct rpc_task *task)
1700{
1701 if (task->tk_ops->rpc_call_prepare != NULL)
1702 return __rpc_restart_call(task, rpc_prepare_task);
1703 return rpc_restart_call(task);
1704}
1705EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1706
1707const char
1708*rpc_proc_name(const struct rpc_task *task)
1709{
1710 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1711
1712 if (proc) {
1713 if (proc->p_name)
1714 return proc->p_name;
1715 else
1716 return "NULL";
1717 } else
1718 return "no proc";
1719}
1720
1721static void
1722__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1723{
1724 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1725 rpc_task_set_rpc_status(task, rpc_status);
1726 rpc_exit(task, tk_status);
1727}
1728
1729static void
1730rpc_call_rpcerror(struct rpc_task *task, int status)
1731{
1732 __rpc_call_rpcerror(task, status, status);
1733}
1734
1735/*
1736 * 0. Initial state
1737 *
1738 * Other FSM states can be visited zero or more times, but
1739 * this state is visited exactly once for each RPC.
1740 */
1741static void
1742call_start(struct rpc_task *task)
1743{
1744 struct rpc_clnt *clnt = task->tk_client;
1745 int idx = task->tk_msg.rpc_proc->p_statidx;
1746
1747 trace_rpc_request(task);
1748
1749 if (task->tk_client->cl_shutdown) {
1750 rpc_call_rpcerror(task, -EIO);
1751 return;
1752 }
1753
1754 /* Increment call count (version might not be valid for ping) */
1755 if (clnt->cl_program->version[clnt->cl_vers])
1756 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1757 clnt->cl_stats->rpccnt++;
1758 task->tk_action = call_reserve;
1759 rpc_task_set_transport(task, clnt);
1760}
1761
1762/*
1763 * 1. Reserve an RPC call slot
1764 */
1765static void
1766call_reserve(struct rpc_task *task)
1767{
1768 task->tk_status = 0;
1769 task->tk_action = call_reserveresult;
1770 xprt_reserve(task);
1771}
1772
1773static void call_retry_reserve(struct rpc_task *task);
1774
1775/*
1776 * 1b. Grok the result of xprt_reserve()
1777 */
1778static void
1779call_reserveresult(struct rpc_task *task)
1780{
1781 int status = task->tk_status;
1782
1783 /*
1784 * After a call to xprt_reserve(), we must have either
1785 * a request slot or else an error status.
1786 */
1787 task->tk_status = 0;
1788 if (status >= 0) {
1789 if (task->tk_rqstp) {
1790 task->tk_action = call_refresh;
1791 return;
1792 }
1793
1794 rpc_call_rpcerror(task, -EIO);
1795 return;
1796 }
1797
1798 switch (status) {
1799 case -ENOMEM:
1800 rpc_delay(task, HZ >> 2);
1801 fallthrough;
1802 case -EAGAIN: /* woken up; retry */
1803 task->tk_action = call_retry_reserve;
1804 return;
1805 default:
1806 rpc_call_rpcerror(task, status);
1807 }
1808}
1809
1810/*
1811 * 1c. Retry reserving an RPC call slot
1812 */
1813static void
1814call_retry_reserve(struct rpc_task *task)
1815{
1816 task->tk_status = 0;
1817 task->tk_action = call_reserveresult;
1818 xprt_retry_reserve(task);
1819}
1820
1821/*
1822 * 2. Bind and/or refresh the credentials
1823 */
1824static void
1825call_refresh(struct rpc_task *task)
1826{
1827 task->tk_action = call_refreshresult;
1828 task->tk_status = 0;
1829 task->tk_client->cl_stats->rpcauthrefresh++;
1830 rpcauth_refreshcred(task);
1831}
1832
1833/*
1834 * 2a. Process the results of a credential refresh
1835 */
1836static void
1837call_refreshresult(struct rpc_task *task)
1838{
1839 int status = task->tk_status;
1840
1841 task->tk_status = 0;
1842 task->tk_action = call_refresh;
1843 switch (status) {
1844 case 0:
1845 if (rpcauth_uptodatecred(task)) {
1846 task->tk_action = call_allocate;
1847 return;
1848 }
1849 /* Use rate-limiting and a max number of retries if refresh
1850 * had status 0 but failed to update the cred.
1851 */
1852 fallthrough;
1853 case -ETIMEDOUT:
1854 rpc_delay(task, 3*HZ);
1855 fallthrough;
1856 case -EAGAIN:
1857 status = -EACCES;
1858 fallthrough;
1859 case -EKEYEXPIRED:
1860 if (!task->tk_cred_retry)
1861 break;
1862 task->tk_cred_retry--;
1863 trace_rpc_retry_refresh_status(task);
1864 return;
1865 case -ENOMEM:
1866 rpc_delay(task, HZ >> 4);
1867 return;
1868 }
1869 trace_rpc_refresh_status(task);
1870 rpc_call_rpcerror(task, status);
1871}
1872
1873/*
1874 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1875 * (Note: buffer memory is freed in xprt_release).
1876 */
1877static void
1878call_allocate(struct rpc_task *task)
1879{
1880 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1881 struct rpc_rqst *req = task->tk_rqstp;
1882 struct rpc_xprt *xprt = req->rq_xprt;
1883 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1884 int status;
1885
1886 task->tk_status = 0;
1887 task->tk_action = call_encode;
1888
1889 if (req->rq_buffer)
1890 return;
1891
1892 if (proc->p_proc != 0) {
1893 BUG_ON(proc->p_arglen == 0);
1894 if (proc->p_decode != NULL)
1895 BUG_ON(proc->p_replen == 0);
1896 }
1897
1898 /*
1899 * Calculate the size (in quads) of the RPC call
1900 * and reply headers, and convert both values
1901 * to byte sizes.
1902 */
1903 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1904 proc->p_arglen;
1905 req->rq_callsize <<= 2;
1906 /*
1907 * Note: the reply buffer must at minimum allocate enough space
1908 * for the 'struct accepted_reply' from RFC5531.
1909 */
1910 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1911 max_t(size_t, proc->p_replen, 2);
1912 req->rq_rcvsize <<= 2;
1913
1914 status = xprt->ops->buf_alloc(task);
1915 trace_rpc_buf_alloc(task, status);
1916 if (status == 0)
1917 return;
1918 if (status != -ENOMEM) {
1919 rpc_call_rpcerror(task, status);
1920 return;
1921 }
1922
1923 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1924 task->tk_action = call_allocate;
1925 rpc_delay(task, HZ>>4);
1926 return;
1927 }
1928
1929 rpc_call_rpcerror(task, -ERESTARTSYS);
1930}
1931
1932static int
1933rpc_task_need_encode(struct rpc_task *task)
1934{
1935 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1936 (!(task->tk_flags & RPC_TASK_SENT) ||
1937 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1938 xprt_request_need_retransmit(task));
1939}
1940
1941static void
1942rpc_xdr_encode(struct rpc_task *task)
1943{
1944 struct rpc_rqst *req = task->tk_rqstp;
1945 struct xdr_stream xdr;
1946
1947 xdr_buf_init(&req->rq_snd_buf,
1948 req->rq_buffer,
1949 req->rq_callsize);
1950 xdr_buf_init(&req->rq_rcv_buf,
1951 req->rq_rbuffer,
1952 req->rq_rcvsize);
1953
1954 req->rq_reply_bytes_recvd = 0;
1955 req->rq_snd_buf.head[0].iov_len = 0;
1956 xdr_init_encode(&xdr, &req->rq_snd_buf,
1957 req->rq_snd_buf.head[0].iov_base, req);
1958 if (rpc_encode_header(task, &xdr))
1959 return;
1960
1961 task->tk_status = rpcauth_wrap_req(task, &xdr);
1962}
1963
1964/*
1965 * 3. Encode arguments of an RPC call
1966 */
1967static void
1968call_encode(struct rpc_task *task)
1969{
1970 if (!rpc_task_need_encode(task))
1971 goto out;
1972
1973 /* Dequeue task from the receive queue while we're encoding */
1974 xprt_request_dequeue_xprt(task);
1975 /* Encode here so that rpcsec_gss can use correct sequence number. */
1976 rpc_xdr_encode(task);
1977 /* Add task to reply queue before transmission to avoid races */
1978 if (task->tk_status == 0 && rpc_reply_expected(task))
1979 task->tk_status = xprt_request_enqueue_receive(task);
1980 /* Did the encode result in an error condition? */
1981 if (task->tk_status != 0) {
1982 /* Was the error nonfatal? */
1983 switch (task->tk_status) {
1984 case -EAGAIN:
1985 case -ENOMEM:
1986 rpc_delay(task, HZ >> 4);
1987 break;
1988 case -EKEYEXPIRED:
1989 if (!task->tk_cred_retry) {
1990 rpc_call_rpcerror(task, task->tk_status);
1991 } else {
1992 task->tk_action = call_refresh;
1993 task->tk_cred_retry--;
1994 trace_rpc_retry_refresh_status(task);
1995 }
1996 break;
1997 default:
1998 rpc_call_rpcerror(task, task->tk_status);
1999 }
2000 return;
2001 }
2002
2003 xprt_request_enqueue_transmit(task);
2004out:
2005 task->tk_action = call_transmit;
2006 /* Check that the connection is OK */
2007 if (!xprt_bound(task->tk_xprt))
2008 task->tk_action = call_bind;
2009 else if (!xprt_connected(task->tk_xprt))
2010 task->tk_action = call_connect;
2011}
2012
2013/*
2014 * Helpers to check if the task was already transmitted, and
2015 * to take action when that is the case.
2016 */
2017static bool
2018rpc_task_transmitted(struct rpc_task *task)
2019{
2020 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
2021}
2022
2023static void
2024rpc_task_handle_transmitted(struct rpc_task *task)
2025{
2026 xprt_end_transmit(task);
2027 task->tk_action = call_transmit_status;
2028}
2029
2030/*
2031 * 4. Get the server port number if not yet set
2032 */
2033static void
2034call_bind(struct rpc_task *task)
2035{
2036 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2037
2038 if (rpc_task_transmitted(task)) {
2039 rpc_task_handle_transmitted(task);
2040 return;
2041 }
2042
2043 if (xprt_bound(xprt)) {
2044 task->tk_action = call_connect;
2045 return;
2046 }
2047
2048 task->tk_action = call_bind_status;
2049 if (!xprt_prepare_transmit(task))
2050 return;
2051
2052 xprt->ops->rpcbind(task);
2053}
2054
2055/*
2056 * 4a. Sort out bind result
2057 */
2058static void
2059call_bind_status(struct rpc_task *task)
2060{
2061 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2062 int status = -EIO;
2063
2064 if (rpc_task_transmitted(task)) {
2065 rpc_task_handle_transmitted(task);
2066 return;
2067 }
2068
2069 if (task->tk_status >= 0)
2070 goto out_next;
2071 if (xprt_bound(xprt)) {
2072 task->tk_status = 0;
2073 goto out_next;
2074 }
2075
2076 switch (task->tk_status) {
2077 case -ENOMEM:
2078 rpc_delay(task, HZ >> 2);
2079 goto retry_timeout;
2080 case -EACCES:
2081 trace_rpcb_prog_unavail_err(task);
2082 /* fail immediately if this is an RPC ping */
2083 if (task->tk_msg.rpc_proc->p_proc == 0) {
2084 status = -EOPNOTSUPP;
2085 break;
2086 }
2087 rpc_delay(task, 3*HZ);
2088 goto retry_timeout;
2089 case -ENOBUFS:
2090 rpc_delay(task, HZ >> 2);
2091 goto retry_timeout;
2092 case -EAGAIN:
2093 goto retry_timeout;
2094 case -ETIMEDOUT:
2095 trace_rpcb_timeout_err(task);
2096 goto retry_timeout;
2097 case -EPFNOSUPPORT:
2098 /* server doesn't support any rpcbind version we know of */
2099 trace_rpcb_bind_version_err(task);
2100 break;
2101 case -EPROTONOSUPPORT:
2102 trace_rpcb_bind_version_err(task);
2103 goto retry_timeout;
2104 case -ECONNREFUSED: /* connection problems */
2105 case -ECONNRESET:
2106 case -ECONNABORTED:
2107 case -ENOTCONN:
2108 case -EHOSTDOWN:
2109 case -ENETDOWN:
2110 case -EHOSTUNREACH:
2111 case -ENETUNREACH:
2112 case -EPIPE:
2113 trace_rpcb_unreachable_err(task);
2114 if (!RPC_IS_SOFTCONN(task)) {
2115 rpc_delay(task, 5*HZ);
2116 goto retry_timeout;
2117 }
2118 status = task->tk_status;
2119 break;
2120 default:
2121 trace_rpcb_unrecognized_err(task);
2122 }
2123
2124 rpc_call_rpcerror(task, status);
2125 return;
2126out_next:
2127 task->tk_action = call_connect;
2128 return;
2129retry_timeout:
2130 task->tk_status = 0;
2131 task->tk_action = call_bind;
2132 rpc_check_timeout(task);
2133}
2134
2135/*
2136 * 4b. Connect to the RPC server
2137 */
2138static void
2139call_connect(struct rpc_task *task)
2140{
2141 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2142
2143 if (rpc_task_transmitted(task)) {
2144 rpc_task_handle_transmitted(task);
2145 return;
2146 }
2147
2148 if (xprt_connected(xprt)) {
2149 task->tk_action = call_transmit;
2150 return;
2151 }
2152
2153 task->tk_action = call_connect_status;
2154 if (task->tk_status < 0)
2155 return;
2156 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2157 rpc_call_rpcerror(task, -ENOTCONN);
2158 return;
2159 }
2160 if (!xprt_prepare_transmit(task))
2161 return;
2162 xprt_connect(task);
2163}
2164
2165/*
2166 * 4c. Sort out connect result
2167 */
2168static void
2169call_connect_status(struct rpc_task *task)
2170{
2171 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2172 struct rpc_clnt *clnt = task->tk_client;
2173 int status = task->tk_status;
2174
2175 if (rpc_task_transmitted(task)) {
2176 rpc_task_handle_transmitted(task);
2177 return;
2178 }
2179
2180 trace_rpc_connect_status(task);
2181
2182 if (task->tk_status == 0) {
2183 clnt->cl_stats->netreconn++;
2184 goto out_next;
2185 }
2186 if (xprt_connected(xprt)) {
2187 task->tk_status = 0;
2188 goto out_next;
2189 }
2190
2191 task->tk_status = 0;
2192 switch (status) {
2193 case -ECONNREFUSED:
2194 case -ECONNRESET:
2195 /* A positive refusal suggests a rebind is needed. */
2196 if (RPC_IS_SOFTCONN(task))
2197 break;
2198 if (clnt->cl_autobind) {
2199 rpc_force_rebind(clnt);
2200 goto out_retry;
2201 }
2202 fallthrough;
2203 case -ECONNABORTED:
2204 case -ENETDOWN:
2205 case -ENETUNREACH:
2206 case -EHOSTUNREACH:
2207 case -EPIPE:
2208 case -EPROTO:
2209 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2210 task->tk_rqstp->rq_connect_cookie);
2211 if (RPC_IS_SOFTCONN(task))
2212 break;
2213 /* retry with existing socket, after a delay */
2214 rpc_delay(task, 3*HZ);
2215 fallthrough;
2216 case -EADDRINUSE:
2217 case -ENOTCONN:
2218 case -EAGAIN:
2219 case -ETIMEDOUT:
2220 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2221 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2222 test_bit(XPRT_REMOVE, &xprt->state)) {
2223 struct rpc_xprt *saved = task->tk_xprt;
2224 struct rpc_xprt_switch *xps;
2225
2226 xps = rpc_clnt_xprt_switch_get(clnt);
2227 if (xps->xps_nxprts > 1) {
2228 long value;
2229
2230 xprt_release(task);
2231 value = atomic_long_dec_return(&xprt->queuelen);
2232 if (value == 0)
2233 rpc_xprt_switch_remove_xprt(xps, saved,
2234 true);
2235 xprt_put(saved);
2236 task->tk_xprt = NULL;
2237 task->tk_action = call_start;
2238 }
2239 xprt_switch_put(xps);
2240 if (!task->tk_xprt)
2241 goto out;
2242 }
2243 goto out_retry;
2244 case -ENOBUFS:
2245 rpc_delay(task, HZ >> 2);
2246 goto out_retry;
2247 }
2248 rpc_call_rpcerror(task, status);
2249 return;
2250out_next:
2251 task->tk_action = call_transmit;
2252 return;
2253out_retry:
2254 /* Check for timeouts before looping back to call_bind */
2255 task->tk_action = call_bind;
2256out:
2257 rpc_check_timeout(task);
2258}
2259
2260/*
2261 * 5. Transmit the RPC request, and wait for reply
2262 */
2263static void
2264call_transmit(struct rpc_task *task)
2265{
2266 if (rpc_task_transmitted(task)) {
2267 rpc_task_handle_transmitted(task);
2268 return;
2269 }
2270
2271 task->tk_action = call_transmit_status;
2272 if (!xprt_prepare_transmit(task))
2273 return;
2274 task->tk_status = 0;
2275 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2276 if (!xprt_connected(task->tk_xprt)) {
2277 task->tk_status = -ENOTCONN;
2278 return;
2279 }
2280 xprt_transmit(task);
2281 }
2282 xprt_end_transmit(task);
2283}
2284
2285/*
2286 * 5a. Handle cleanup after a transmission
2287 */
2288static void
2289call_transmit_status(struct rpc_task *task)
2290{
2291 task->tk_action = call_status;
2292
2293 /*
2294 * Common case: success. Force the compiler to put this
2295 * test first.
2296 */
2297 if (rpc_task_transmitted(task)) {
2298 task->tk_status = 0;
2299 xprt_request_wait_receive(task);
2300 return;
2301 }
2302
2303 switch (task->tk_status) {
2304 default:
2305 break;
2306 case -EBADMSG:
2307 task->tk_status = 0;
2308 task->tk_action = call_encode;
2309 break;
2310 /*
2311 * Special cases: if we've been waiting on the
2312 * socket's write_space() callback, or if the
2313 * socket just returned a connection error,
2314 * then hold onto the transport lock.
2315 */
2316 case -ENOMEM:
2317 case -ENOBUFS:
2318 rpc_delay(task, HZ>>2);
2319 fallthrough;
2320 case -EBADSLT:
2321 case -EAGAIN:
2322 task->tk_action = call_transmit;
2323 task->tk_status = 0;
2324 break;
2325 case -ECONNREFUSED:
2326 case -EHOSTDOWN:
2327 case -ENETDOWN:
2328 case -EHOSTUNREACH:
2329 case -ENETUNREACH:
2330 case -EPERM:
2331 if (RPC_IS_SOFTCONN(task)) {
2332 if (!task->tk_msg.rpc_proc->p_proc)
2333 trace_xprt_ping(task->tk_xprt,
2334 task->tk_status);
2335 rpc_call_rpcerror(task, task->tk_status);
2336 return;
2337 }
2338 fallthrough;
2339 case -ECONNRESET:
2340 case -ECONNABORTED:
2341 case -EADDRINUSE:
2342 case -ENOTCONN:
2343 case -EPIPE:
2344 task->tk_action = call_bind;
2345 task->tk_status = 0;
2346 break;
2347 }
2348 rpc_check_timeout(task);
2349}
2350
2351#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2352static void call_bc_transmit(struct rpc_task *task);
2353static void call_bc_transmit_status(struct rpc_task *task);
2354
2355static void
2356call_bc_encode(struct rpc_task *task)
2357{
2358 xprt_request_enqueue_transmit(task);
2359 task->tk_action = call_bc_transmit;
2360}
2361
2362/*
2363 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2364 * addition, disconnect on connectivity errors.
2365 */
2366static void
2367call_bc_transmit(struct rpc_task *task)
2368{
2369 task->tk_action = call_bc_transmit_status;
2370 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2371 if (!xprt_prepare_transmit(task))
2372 return;
2373 task->tk_status = 0;
2374 xprt_transmit(task);
2375 }
2376 xprt_end_transmit(task);
2377}
2378
2379static void
2380call_bc_transmit_status(struct rpc_task *task)
2381{
2382 struct rpc_rqst *req = task->tk_rqstp;
2383
2384 if (rpc_task_transmitted(task))
2385 task->tk_status = 0;
2386
2387 switch (task->tk_status) {
2388 case 0:
2389 /* Success */
2390 case -ENETDOWN:
2391 case -EHOSTDOWN:
2392 case -EHOSTUNREACH:
2393 case -ENETUNREACH:
2394 case -ECONNRESET:
2395 case -ECONNREFUSED:
2396 case -EADDRINUSE:
2397 case -ENOTCONN:
2398 case -EPIPE:
2399 break;
2400 case -ENOMEM:
2401 case -ENOBUFS:
2402 rpc_delay(task, HZ>>2);
2403 fallthrough;
2404 case -EBADSLT:
2405 case -EAGAIN:
2406 task->tk_status = 0;
2407 task->tk_action = call_bc_transmit;
2408 return;
2409 case -ETIMEDOUT:
2410 /*
2411 * Problem reaching the server. Disconnect and let the
2412 * forechannel reestablish the connection. The server will
2413 * have to retransmit the backchannel request and we'll
2414 * reprocess it. Since these ops are idempotent, there's no
2415 * need to cache our reply at this time.
2416 */
2417 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2418 "error: %d\n", task->tk_status);
2419 xprt_conditional_disconnect(req->rq_xprt,
2420 req->rq_connect_cookie);
2421 break;
2422 default:
2423 /*
2424 * We were unable to reply and will have to drop the
2425 * request. The server should reconnect and retransmit.
2426 */
2427 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2428 "error: %d\n", task->tk_status);
2429 break;
2430 }
2431 task->tk_action = rpc_exit_task;
2432}
2433#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2434
2435/*
2436 * 6. Sort out the RPC call status
2437 */
2438static void
2439call_status(struct rpc_task *task)
2440{
2441 struct rpc_clnt *clnt = task->tk_client;
2442 int status;
2443
2444 if (!task->tk_msg.rpc_proc->p_proc)
2445 trace_xprt_ping(task->tk_xprt, task->tk_status);
2446
2447 status = task->tk_status;
2448 if (status >= 0) {
2449 task->tk_action = call_decode;
2450 return;
2451 }
2452
2453 trace_rpc_call_status(task);
2454 task->tk_status = 0;
2455 switch(status) {
2456 case -EHOSTDOWN:
2457 case -ENETDOWN:
2458 case -EHOSTUNREACH:
2459 case -ENETUNREACH:
2460 case -EPERM:
2461 if (RPC_IS_SOFTCONN(task))
2462 goto out_exit;
2463 /*
2464 * Delay any retries for 3 seconds, then handle as if it
2465 * were a timeout.
2466 */
2467 rpc_delay(task, 3*HZ);
2468 fallthrough;
2469 case -ETIMEDOUT:
2470 break;
2471 case -ECONNREFUSED:
2472 case -ECONNRESET:
2473 case -ECONNABORTED:
2474 case -ENOTCONN:
2475 rpc_force_rebind(clnt);
2476 break;
2477 case -EADDRINUSE:
2478 rpc_delay(task, 3*HZ);
2479 fallthrough;
2480 case -EPIPE:
2481 case -EAGAIN:
2482 break;
2483 case -ENFILE:
2484 case -ENOBUFS:
2485 case -ENOMEM:
2486 rpc_delay(task, HZ>>2);
2487 break;
2488 case -EIO:
2489 /* shutdown or soft timeout */
2490 goto out_exit;
2491 default:
2492 if (clnt->cl_chatty)
2493 printk("%s: RPC call returned error %d\n",
2494 clnt->cl_program->name, -status);
2495 goto out_exit;
2496 }
2497 task->tk_action = call_encode;
2498 rpc_check_timeout(task);
2499 return;
2500out_exit:
2501 rpc_call_rpcerror(task, status);
2502}
2503
2504static bool
2505rpc_check_connected(const struct rpc_rqst *req)
2506{
2507 /* No allocated request or transport? return true */
2508 if (!req || !req->rq_xprt)
2509 return true;
2510 return xprt_connected(req->rq_xprt);
2511}
2512
2513static void
2514rpc_check_timeout(struct rpc_task *task)
2515{
2516 struct rpc_clnt *clnt = task->tk_client;
2517
2518 if (RPC_SIGNALLED(task))
2519 return;
2520
2521 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2522 return;
2523
2524 trace_rpc_timeout_status(task);
2525 task->tk_timeouts++;
2526
2527 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2528 rpc_call_rpcerror(task, -ETIMEDOUT);
2529 return;
2530 }
2531
2532 if (RPC_IS_SOFT(task)) {
2533 /*
2534 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2535 * been sent, it should time out only if the transport
2536 * connection gets terminally broken.
2537 */
2538 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2539 rpc_check_connected(task->tk_rqstp))
2540 return;
2541
2542 if (clnt->cl_chatty) {
2543 pr_notice_ratelimited(
2544 "%s: server %s not responding, timed out\n",
2545 clnt->cl_program->name,
2546 task->tk_xprt->servername);
2547 }
2548 if (task->tk_flags & RPC_TASK_TIMEOUT)
2549 rpc_call_rpcerror(task, -ETIMEDOUT);
2550 else
2551 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2552 return;
2553 }
2554
2555 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2556 task->tk_flags |= RPC_CALL_MAJORSEEN;
2557 if (clnt->cl_chatty) {
2558 pr_notice_ratelimited(
2559 "%s: server %s not responding, still trying\n",
2560 clnt->cl_program->name,
2561 task->tk_xprt->servername);
2562 }
2563 }
2564 rpc_force_rebind(clnt);
2565 /*
2566 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2567 * event? RFC2203 requires the server to drop all such requests.
2568 */
2569 rpcauth_invalcred(task);
2570}
2571
2572/*
2573 * 7. Decode the RPC reply
2574 */
2575static void
2576call_decode(struct rpc_task *task)
2577{
2578 struct rpc_clnt *clnt = task->tk_client;
2579 struct rpc_rqst *req = task->tk_rqstp;
2580 struct xdr_stream xdr;
2581 int err;
2582
2583 if (!task->tk_msg.rpc_proc->p_decode) {
2584 task->tk_action = rpc_exit_task;
2585 return;
2586 }
2587
2588 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2589 if (clnt->cl_chatty) {
2590 pr_notice_ratelimited("%s: server %s OK\n",
2591 clnt->cl_program->name,
2592 task->tk_xprt->servername);
2593 }
2594 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2595 }
2596
2597 /*
2598 * Did we ever call xprt_complete_rqst()? If not, we should assume
2599 * the message is incomplete.
2600 */
2601 err = -EAGAIN;
2602 if (!req->rq_reply_bytes_recvd)
2603 goto out;
2604
2605 /* Ensure that we see all writes made by xprt_complete_rqst()
2606 * before it changed req->rq_reply_bytes_recvd.
2607 */
2608 smp_rmb();
2609
2610 req->rq_rcv_buf.len = req->rq_private_buf.len;
2611 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2612
2613 /* Check that the softirq receive buffer is valid */
2614 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2615 sizeof(req->rq_rcv_buf)) != 0);
2616
2617 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2618 req->rq_rcv_buf.head[0].iov_base, req);
2619 err = rpc_decode_header(task, &xdr);
2620out:
2621 switch (err) {
2622 case 0:
2623 task->tk_action = rpc_exit_task;
2624 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2625 xdr_finish_decode(&xdr);
2626 return;
2627 case -EAGAIN:
2628 task->tk_status = 0;
2629 if (task->tk_client->cl_discrtry)
2630 xprt_conditional_disconnect(req->rq_xprt,
2631 req->rq_connect_cookie);
2632 task->tk_action = call_encode;
2633 rpc_check_timeout(task);
2634 break;
2635 case -EKEYREJECTED:
2636 task->tk_action = call_reserve;
2637 rpc_check_timeout(task);
2638 rpcauth_invalcred(task);
2639 /* Ensure we obtain a new XID if we retry! */
2640 xprt_release(task);
2641 }
2642}
2643
2644static int
2645rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2646{
2647 struct rpc_clnt *clnt = task->tk_client;
2648 struct rpc_rqst *req = task->tk_rqstp;
2649 __be32 *p;
2650 int error;
2651
2652 error = -EMSGSIZE;
2653 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2654 if (!p)
2655 goto out_fail;
2656 *p++ = req->rq_xid;
2657 *p++ = rpc_call;
2658 *p++ = cpu_to_be32(RPC_VERSION);
2659 *p++ = cpu_to_be32(clnt->cl_prog);
2660 *p++ = cpu_to_be32(clnt->cl_vers);
2661 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2662
2663 error = rpcauth_marshcred(task, xdr);
2664 if (error < 0)
2665 goto out_fail;
2666 return 0;
2667out_fail:
2668 trace_rpc_bad_callhdr(task);
2669 rpc_call_rpcerror(task, error);
2670 return error;
2671}
2672
2673static noinline int
2674rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2675{
2676 struct rpc_clnt *clnt = task->tk_client;
2677 int error;
2678 __be32 *p;
2679
2680 /* RFC-1014 says that the representation of XDR data must be a
2681 * multiple of four bytes
2682 * - if it isn't pointer subtraction in the NFS client may give
2683 * undefined results
2684 */
2685 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2686 goto out_unparsable;
2687
2688 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2689 if (!p)
2690 goto out_unparsable;
2691 p++; /* skip XID */
2692 if (*p++ != rpc_reply)
2693 goto out_unparsable;
2694 if (*p++ != rpc_msg_accepted)
2695 goto out_msg_denied;
2696
2697 error = rpcauth_checkverf(task, xdr);
2698 if (error)
2699 goto out_verifier;
2700
2701 p = xdr_inline_decode(xdr, sizeof(*p));
2702 if (!p)
2703 goto out_unparsable;
2704 switch (*p) {
2705 case rpc_success:
2706 return 0;
2707 case rpc_prog_unavail:
2708 trace_rpc__prog_unavail(task);
2709 error = -EPFNOSUPPORT;
2710 goto out_err;
2711 case rpc_prog_mismatch:
2712 trace_rpc__prog_mismatch(task);
2713 error = -EPROTONOSUPPORT;
2714 goto out_err;
2715 case rpc_proc_unavail:
2716 trace_rpc__proc_unavail(task);
2717 error = -EOPNOTSUPP;
2718 goto out_err;
2719 case rpc_garbage_args:
2720 case rpc_system_err:
2721 trace_rpc__garbage_args(task);
2722 error = -EIO;
2723 break;
2724 default:
2725 goto out_unparsable;
2726 }
2727
2728out_garbage:
2729 clnt->cl_stats->rpcgarbage++;
2730 if (task->tk_garb_retry) {
2731 task->tk_garb_retry--;
2732 task->tk_action = call_encode;
2733 return -EAGAIN;
2734 }
2735out_err:
2736 rpc_call_rpcerror(task, error);
2737 return error;
2738
2739out_unparsable:
2740 trace_rpc__unparsable(task);
2741 error = -EIO;
2742 goto out_garbage;
2743
2744out_verifier:
2745 trace_rpc_bad_verifier(task);
2746 switch (error) {
2747 case -EPROTONOSUPPORT:
2748 goto out_err;
2749 case -EACCES:
2750 /* Re-encode with a fresh cred */
2751 fallthrough;
2752 default:
2753 goto out_garbage;
2754 }
2755
2756out_msg_denied:
2757 error = -EACCES;
2758 p = xdr_inline_decode(xdr, sizeof(*p));
2759 if (!p)
2760 goto out_unparsable;
2761 switch (*p++) {
2762 case rpc_auth_error:
2763 break;
2764 case rpc_mismatch:
2765 trace_rpc__mismatch(task);
2766 error = -EPROTONOSUPPORT;
2767 goto out_err;
2768 default:
2769 goto out_unparsable;
2770 }
2771
2772 p = xdr_inline_decode(xdr, sizeof(*p));
2773 if (!p)
2774 goto out_unparsable;
2775 switch (*p++) {
2776 case rpc_autherr_rejectedcred:
2777 case rpc_autherr_rejectedverf:
2778 case rpcsec_gsserr_credproblem:
2779 case rpcsec_gsserr_ctxproblem:
2780 rpcauth_invalcred(task);
2781 if (!task->tk_cred_retry)
2782 break;
2783 task->tk_cred_retry--;
2784 trace_rpc__stale_creds(task);
2785 return -EKEYREJECTED;
2786 case rpc_autherr_badcred:
2787 case rpc_autherr_badverf:
2788 /* possibly garbled cred/verf? */
2789 if (!task->tk_garb_retry)
2790 break;
2791 task->tk_garb_retry--;
2792 trace_rpc__bad_creds(task);
2793 task->tk_action = call_encode;
2794 return -EAGAIN;
2795 case rpc_autherr_tooweak:
2796 trace_rpc__auth_tooweak(task);
2797 pr_warn("RPC: server %s requires stronger authentication.\n",
2798 task->tk_xprt->servername);
2799 break;
2800 default:
2801 goto out_unparsable;
2802 }
2803 goto out_err;
2804}
2805
2806static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2807 const void *obj)
2808{
2809}
2810
2811static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2812 void *obj)
2813{
2814 return 0;
2815}
2816
2817static const struct rpc_procinfo rpcproc_null = {
2818 .p_encode = rpcproc_encode_null,
2819 .p_decode = rpcproc_decode_null,
2820};
2821
2822static const struct rpc_procinfo rpcproc_null_noreply = {
2823 .p_encode = rpcproc_encode_null,
2824};
2825
2826static void
2827rpc_null_call_prepare(struct rpc_task *task, void *data)
2828{
2829 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2830 rpc_call_start(task);
2831}
2832
2833static const struct rpc_call_ops rpc_null_ops = {
2834 .rpc_call_prepare = rpc_null_call_prepare,
2835 .rpc_call_done = rpc_default_callback,
2836};
2837
2838static
2839struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2840 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2841 const struct rpc_call_ops *ops, void *data)
2842{
2843 struct rpc_message msg = {
2844 .rpc_proc = &rpcproc_null,
2845 };
2846 struct rpc_task_setup task_setup_data = {
2847 .rpc_client = clnt,
2848 .rpc_xprt = xprt,
2849 .rpc_message = &msg,
2850 .rpc_op_cred = cred,
2851 .callback_ops = ops ?: &rpc_null_ops,
2852 .callback_data = data,
2853 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2854 RPC_TASK_NULLCREDS,
2855 };
2856
2857 return rpc_run_task(&task_setup_data);
2858}
2859
2860struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2861{
2862 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2863}
2864EXPORT_SYMBOL_GPL(rpc_call_null);
2865
2866static int rpc_ping(struct rpc_clnt *clnt)
2867{
2868 struct rpc_task *task;
2869 int status;
2870
2871 if (clnt->cl_auth->au_ops->ping)
2872 return clnt->cl_auth->au_ops->ping(clnt);
2873
2874 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2875 if (IS_ERR(task))
2876 return PTR_ERR(task);
2877 status = task->tk_status;
2878 rpc_put_task(task);
2879 return status;
2880}
2881
2882static int rpc_ping_noreply(struct rpc_clnt *clnt)
2883{
2884 struct rpc_message msg = {
2885 .rpc_proc = &rpcproc_null_noreply,
2886 };
2887 struct rpc_task_setup task_setup_data = {
2888 .rpc_client = clnt,
2889 .rpc_message = &msg,
2890 .callback_ops = &rpc_null_ops,
2891 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2892 };
2893 struct rpc_task *task;
2894 int status;
2895
2896 task = rpc_run_task(&task_setup_data);
2897 if (IS_ERR(task))
2898 return PTR_ERR(task);
2899 status = task->tk_status;
2900 rpc_put_task(task);
2901 return status;
2902}
2903
2904struct rpc_cb_add_xprt_calldata {
2905 struct rpc_xprt_switch *xps;
2906 struct rpc_xprt *xprt;
2907};
2908
2909static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2910{
2911 struct rpc_cb_add_xprt_calldata *data = calldata;
2912
2913 if (task->tk_status == 0)
2914 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2915}
2916
2917static void rpc_cb_add_xprt_release(void *calldata)
2918{
2919 struct rpc_cb_add_xprt_calldata *data = calldata;
2920
2921 xprt_put(data->xprt);
2922 xprt_switch_put(data->xps);
2923 kfree(data);
2924}
2925
2926static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2927 .rpc_call_prepare = rpc_null_call_prepare,
2928 .rpc_call_done = rpc_cb_add_xprt_done,
2929 .rpc_release = rpc_cb_add_xprt_release,
2930};
2931
2932/**
2933 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2934 * @clnt: pointer to struct rpc_clnt
2935 * @xps: pointer to struct rpc_xprt_switch,
2936 * @xprt: pointer struct rpc_xprt
2937 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport
2938 */
2939int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2940 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2941 void *in_max_connect)
2942{
2943 struct rpc_cb_add_xprt_calldata *data;
2944 struct rpc_task *task;
2945 int max_connect = clnt->cl_max_connect;
2946
2947 if (in_max_connect)
2948 max_connect = *(int *)in_max_connect;
2949 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) {
2950 rcu_read_lock();
2951 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2952 "transport to server: %s\n", max_connect,
2953 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2954 rcu_read_unlock();
2955 return -EINVAL;
2956 }
2957
2958 data = kmalloc(sizeof(*data), GFP_KERNEL);
2959 if (!data)
2960 return -ENOMEM;
2961 data->xps = xprt_switch_get(xps);
2962 data->xprt = xprt_get(xprt);
2963 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2964 rpc_cb_add_xprt_release(data);
2965 goto success;
2966 }
2967
2968 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2969 &rpc_cb_add_xprt_call_ops, data);
2970 if (IS_ERR(task))
2971 return PTR_ERR(task);
2972
2973 data->xps->xps_nunique_destaddr_xprts++;
2974 rpc_put_task(task);
2975success:
2976 return 1;
2977}
2978EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2979
2980static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2981 struct rpc_xprt *xprt,
2982 struct rpc_add_xprt_test *data)
2983{
2984 struct rpc_task *task;
2985 int status = -EADDRINUSE;
2986
2987 /* Test the connection */
2988 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2989 if (IS_ERR(task))
2990 return PTR_ERR(task);
2991
2992 status = task->tk_status;
2993 rpc_put_task(task);
2994
2995 if (status < 0)
2996 return status;
2997
2998 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2999 data->add_xprt_test(clnt, xprt, data->data);
3000
3001 return 0;
3002}
3003
3004/**
3005 * rpc_clnt_setup_test_and_add_xprt()
3006 *
3007 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
3008 * 1) caller of the test function must dereference the rpc_xprt_switch
3009 * and the rpc_xprt.
3010 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
3011 * the rpc_call_done routine.
3012 *
3013 * Upon success (return of 1), the test function adds the new
3014 * transport to the rpc_clnt xprt switch
3015 *
3016 * @clnt: struct rpc_clnt to get the new transport
3017 * @xps: the rpc_xprt_switch to hold the new transport
3018 * @xprt: the rpc_xprt to test
3019 * @data: a struct rpc_add_xprt_test pointer that holds the test function
3020 * and test function call data
3021 */
3022int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
3023 struct rpc_xprt_switch *xps,
3024 struct rpc_xprt *xprt,
3025 void *data)
3026{
3027 int status = -EADDRINUSE;
3028
3029 xprt = xprt_get(xprt);
3030 xprt_switch_get(xps);
3031
3032 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
3033 goto out_err;
3034
3035 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3036 if (status < 0)
3037 goto out_err;
3038
3039 status = 1;
3040out_err:
3041 xprt_put(xprt);
3042 xprt_switch_put(xps);
3043 if (status < 0)
3044 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3045 "added\n", status,
3046 xprt->address_strings[RPC_DISPLAY_ADDR]);
3047 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3048 return status;
3049}
3050EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3051
3052/**
3053 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3054 * @clnt: pointer to struct rpc_clnt
3055 * @xprtargs: pointer to struct xprt_create
3056 * @setup: callback to test and/or set up the connection
3057 * @data: pointer to setup function data
3058 *
3059 * Creates a new transport using the parameters set in args and
3060 * adds it to clnt.
3061 * If ping is set, then test that connectivity succeeds before
3062 * adding the new transport.
3063 *
3064 */
3065int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3066 struct xprt_create *xprtargs,
3067 int (*setup)(struct rpc_clnt *,
3068 struct rpc_xprt_switch *,
3069 struct rpc_xprt *,
3070 void *),
3071 void *data)
3072{
3073 struct rpc_xprt_switch *xps;
3074 struct rpc_xprt *xprt;
3075 unsigned long connect_timeout;
3076 unsigned long reconnect_timeout;
3077 unsigned char resvport, reuseport;
3078 int ret = 0, ident;
3079
3080 rcu_read_lock();
3081 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3082 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3083 if (xps == NULL || xprt == NULL) {
3084 rcu_read_unlock();
3085 xprt_switch_put(xps);
3086 return -EAGAIN;
3087 }
3088 resvport = xprt->resvport;
3089 reuseport = xprt->reuseport;
3090 connect_timeout = xprt->connect_timeout;
3091 reconnect_timeout = xprt->max_reconnect_timeout;
3092 ident = xprt->xprt_class->ident;
3093 rcu_read_unlock();
3094
3095 if (!xprtargs->ident)
3096 xprtargs->ident = ident;
3097 xprtargs->xprtsec = clnt->cl_xprtsec;
3098 xprt = xprt_create_transport(xprtargs);
3099 if (IS_ERR(xprt)) {
3100 ret = PTR_ERR(xprt);
3101 goto out_put_switch;
3102 }
3103 xprt->resvport = resvport;
3104 xprt->reuseport = reuseport;
3105
3106 if (xprtargs->connect_timeout)
3107 connect_timeout = xprtargs->connect_timeout;
3108 if (xprtargs->reconnect_timeout)
3109 reconnect_timeout = xprtargs->reconnect_timeout;
3110 if (xprt->ops->set_connect_timeout != NULL)
3111 xprt->ops->set_connect_timeout(xprt,
3112 connect_timeout,
3113 reconnect_timeout);
3114
3115 rpc_xprt_switch_set_roundrobin(xps);
3116 if (setup) {
3117 ret = setup(clnt, xps, xprt, data);
3118 if (ret != 0)
3119 goto out_put_xprt;
3120 }
3121 rpc_xprt_switch_add_xprt(xps, xprt);
3122out_put_xprt:
3123 xprt_put(xprt);
3124out_put_switch:
3125 xprt_switch_put(xps);
3126 return ret;
3127}
3128EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3129
3130static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3131 struct rpc_xprt *xprt,
3132 struct rpc_add_xprt_test *data)
3133{
3134 struct rpc_xprt *main_xprt;
3135 int status = 0;
3136
3137 xprt_get(xprt);
3138
3139 rcu_read_lock();
3140 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3141 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3142 (struct sockaddr *)&main_xprt->addr);
3143 rcu_read_unlock();
3144 xprt_put(main_xprt);
3145 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3146 goto out;
3147
3148 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3149out:
3150 xprt_put(xprt);
3151 return status;
3152}
3153
3154/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3155 * @clnt rpc_clnt structure
3156 *
3157 * For each offlined transport found in the rpc_clnt structure call
3158 * the function rpc_xprt_probe_trunked() which will determine if this
3159 * transport still belongs to the trunking group.
3160 */
3161void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3162 struct rpc_add_xprt_test *data)
3163{
3164 struct rpc_xprt_iter xpi;
3165 int ret;
3166
3167 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3168 if (ret)
3169 return;
3170 for (;;) {
3171 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3172
3173 if (!xprt)
3174 break;
3175 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3176 xprt_put(xprt);
3177 if (ret < 0)
3178 break;
3179 xprt_iter_rewind(&xpi);
3180 }
3181 xprt_iter_destroy(&xpi);
3182}
3183EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3184
3185static int rpc_xprt_offline(struct rpc_clnt *clnt,
3186 struct rpc_xprt *xprt,
3187 void *data)
3188{
3189 struct rpc_xprt *main_xprt;
3190 struct rpc_xprt_switch *xps;
3191 int err = 0;
3192
3193 xprt_get(xprt);
3194
3195 rcu_read_lock();
3196 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3197 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3198 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3199 (struct sockaddr *)&main_xprt->addr);
3200 rcu_read_unlock();
3201 xprt_put(main_xprt);
3202 if (err)
3203 goto out;
3204
3205 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3206 err = -EINTR;
3207 goto out;
3208 }
3209 xprt_set_offline_locked(xprt, xps);
3210
3211 xprt_release_write(xprt, NULL);
3212out:
3213 xprt_put(xprt);
3214 xprt_switch_put(xps);
3215 return err;
3216}
3217
3218/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3219 * @clnt rpc_clnt structure
3220 *
3221 * For each active transport found in the rpc_clnt structure call
3222 * the function rpc_xprt_offline() which will identify trunked transports
3223 * and will mark them offline.
3224 */
3225void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3226{
3227 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3228}
3229EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3230
3231struct connect_timeout_data {
3232 unsigned long connect_timeout;
3233 unsigned long reconnect_timeout;
3234};
3235
3236static int
3237rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3238 struct rpc_xprt *xprt,
3239 void *data)
3240{
3241 struct connect_timeout_data *timeo = data;
3242
3243 if (xprt->ops->set_connect_timeout)
3244 xprt->ops->set_connect_timeout(xprt,
3245 timeo->connect_timeout,
3246 timeo->reconnect_timeout);
3247 return 0;
3248}
3249
3250void
3251rpc_set_connect_timeout(struct rpc_clnt *clnt,
3252 unsigned long connect_timeout,
3253 unsigned long reconnect_timeout)
3254{
3255 struct connect_timeout_data timeout = {
3256 .connect_timeout = connect_timeout,
3257 .reconnect_timeout = reconnect_timeout,
3258 };
3259 rpc_clnt_iterate_for_each_xprt(clnt,
3260 rpc_xprt_set_connect_timeout,
3261 &timeout);
3262}
3263EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3264
3265void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3266{
3267 struct rpc_xprt_switch *xps;
3268
3269 xps = rpc_clnt_xprt_switch_get(clnt);
3270 xprt_set_online_locked(xprt, xps);
3271 xprt_switch_put(xps);
3272}
3273
3274void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3275{
3276 struct rpc_xprt_switch *xps;
3277
3278 if (rpc_clnt_xprt_switch_has_addr(clnt,
3279 (const struct sockaddr *)&xprt->addr)) {
3280 return rpc_clnt_xprt_set_online(clnt, xprt);
3281 }
3282
3283 xps = rpc_clnt_xprt_switch_get(clnt);
3284 rpc_xprt_switch_add_xprt(xps, xprt);
3285 xprt_switch_put(xps);
3286}
3287EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3288
3289void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3290{
3291 struct rpc_xprt_switch *xps;
3292
3293 rcu_read_lock();
3294 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3295 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3296 xprt, 0);
3297 xps->xps_nunique_destaddr_xprts--;
3298 rcu_read_unlock();
3299}
3300EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3301
3302bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3303 const struct sockaddr *sap)
3304{
3305 struct rpc_xprt_switch *xps;
3306 bool ret;
3307
3308 rcu_read_lock();
3309 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3310 ret = rpc_xprt_switch_has_addr(xps, sap);
3311 rcu_read_unlock();
3312 return ret;
3313}
3314EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3315
3316#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3317static void rpc_show_header(void)
3318{
3319 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3320 "-timeout ---ops--\n");
3321}
3322
3323static void rpc_show_task(const struct rpc_clnt *clnt,
3324 const struct rpc_task *task)
3325{
3326 const char *rpc_waitq = "none";
3327
3328 if (RPC_IS_QUEUED(task))
3329 rpc_waitq = rpc_qname(task->tk_waitqueue);
3330
3331 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3332 task->tk_pid, task->tk_flags, task->tk_status,
3333 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3334 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3335 task->tk_action, rpc_waitq);
3336}
3337
3338void rpc_show_tasks(struct net *net)
3339{
3340 struct rpc_clnt *clnt;
3341 struct rpc_task *task;
3342 int header = 0;
3343 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3344
3345 spin_lock(&sn->rpc_client_lock);
3346 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3347 spin_lock(&clnt->cl_lock);
3348 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3349 if (!header) {
3350 rpc_show_header();
3351 header++;
3352 }
3353 rpc_show_task(clnt, task);
3354 }
3355 spin_unlock(&clnt->cl_lock);
3356 }
3357 spin_unlock(&sn->rpc_client_lock);
3358}
3359#endif
3360
3361#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3362static int
3363rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3364 struct rpc_xprt *xprt,
3365 void *dummy)
3366{
3367 return xprt_enable_swap(xprt);
3368}
3369
3370int
3371rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3372{
3373 while (clnt != clnt->cl_parent)
3374 clnt = clnt->cl_parent;
3375 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3376 return rpc_clnt_iterate_for_each_xprt(clnt,
3377 rpc_clnt_swap_activate_callback, NULL);
3378 return 0;
3379}
3380EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3381
3382static int
3383rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3384 struct rpc_xprt *xprt,
3385 void *dummy)
3386{
3387 xprt_disable_swap(xprt);
3388 return 0;
3389}
3390
3391void
3392rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3393{
3394 while (clnt != clnt->cl_parent)
3395 clnt = clnt->cl_parent;
3396 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3397 rpc_clnt_iterate_for_each_xprt(clnt,
3398 rpc_clnt_swap_deactivate_callback, NULL);
3399}
3400EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3401#endif /* CONFIG_SUNRPC_SWAP */
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/kallsyms.h>
25#include <linux/mm.h>
26#include <linux/namei.h>
27#include <linux/mount.h>
28#include <linux/slab.h>
29#include <linux/rcupdate.h>
30#include <linux/utsname.h>
31#include <linux/workqueue.h>
32#include <linux/in.h>
33#include <linux/in6.h>
34#include <linux/un.h>
35
36#include <linux/sunrpc/clnt.h>
37#include <linux/sunrpc/addr.h>
38#include <linux/sunrpc/rpc_pipe_fs.h>
39#include <linux/sunrpc/metrics.h>
40#include <linux/sunrpc/bc_xprt.h>
41#include <trace/events/sunrpc.h>
42
43#include "sunrpc.h"
44#include "sysfs.h"
45#include "netns.h"
46
47#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
48# define RPCDBG_FACILITY RPCDBG_CALL
49#endif
50
51/*
52 * All RPC clients are linked into this list
53 */
54
55static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
56
57
58static void call_start(struct rpc_task *task);
59static void call_reserve(struct rpc_task *task);
60static void call_reserveresult(struct rpc_task *task);
61static void call_allocate(struct rpc_task *task);
62static void call_encode(struct rpc_task *task);
63static void call_decode(struct rpc_task *task);
64static void call_bind(struct rpc_task *task);
65static void call_bind_status(struct rpc_task *task);
66static void call_transmit(struct rpc_task *task);
67static void call_status(struct rpc_task *task);
68static void call_transmit_status(struct rpc_task *task);
69static void call_refresh(struct rpc_task *task);
70static void call_refreshresult(struct rpc_task *task);
71static void call_connect(struct rpc_task *task);
72static void call_connect_status(struct rpc_task *task);
73
74static int rpc_encode_header(struct rpc_task *task,
75 struct xdr_stream *xdr);
76static int rpc_decode_header(struct rpc_task *task,
77 struct xdr_stream *xdr);
78static int rpc_ping(struct rpc_clnt *clnt);
79static int rpc_ping_noreply(struct rpc_clnt *clnt);
80static void rpc_check_timeout(struct rpc_task *task);
81
82static void rpc_register_client(struct rpc_clnt *clnt)
83{
84 struct net *net = rpc_net_ns(clnt);
85 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
86
87 spin_lock(&sn->rpc_client_lock);
88 list_add(&clnt->cl_clients, &sn->all_clients);
89 spin_unlock(&sn->rpc_client_lock);
90}
91
92static void rpc_unregister_client(struct rpc_clnt *clnt)
93{
94 struct net *net = rpc_net_ns(clnt);
95 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
96
97 spin_lock(&sn->rpc_client_lock);
98 list_del(&clnt->cl_clients);
99 spin_unlock(&sn->rpc_client_lock);
100}
101
102static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103{
104 rpc_remove_client_dir(clnt);
105}
106
107static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
108{
109 struct net *net = rpc_net_ns(clnt);
110 struct super_block *pipefs_sb;
111
112 pipefs_sb = rpc_get_sb_net(net);
113 if (pipefs_sb) {
114 __rpc_clnt_remove_pipedir(clnt);
115 rpc_put_sb_net(net);
116 }
117}
118
119static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
120 struct rpc_clnt *clnt)
121{
122 static uint32_t clntid;
123 const char *dir_name = clnt->cl_program->pipe_dir_name;
124 char name[15];
125 struct dentry *dir, *dentry;
126
127 dir = rpc_d_lookup_sb(sb, dir_name);
128 if (dir == NULL) {
129 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
130 return dir;
131 }
132 for (;;) {
133 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
134 name[sizeof(name) - 1] = '\0';
135 dentry = rpc_create_client_dir(dir, name, clnt);
136 if (!IS_ERR(dentry))
137 break;
138 if (dentry == ERR_PTR(-EEXIST))
139 continue;
140 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
141 " %s/%s, error %ld\n",
142 dir_name, name, PTR_ERR(dentry));
143 break;
144 }
145 dput(dir);
146 return dentry;
147}
148
149static int
150rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
151{
152 struct dentry *dentry;
153
154 if (clnt->cl_program->pipe_dir_name != NULL) {
155 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
156 if (IS_ERR(dentry))
157 return PTR_ERR(dentry);
158 }
159 return 0;
160}
161
162static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
163{
164 if (clnt->cl_program->pipe_dir_name == NULL)
165 return 1;
166
167 switch (event) {
168 case RPC_PIPEFS_MOUNT:
169 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
170 return 1;
171 if (refcount_read(&clnt->cl_count) == 0)
172 return 1;
173 break;
174 case RPC_PIPEFS_UMOUNT:
175 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
176 return 1;
177 break;
178 }
179 return 0;
180}
181
182static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
183 struct super_block *sb)
184{
185 struct dentry *dentry;
186
187 switch (event) {
188 case RPC_PIPEFS_MOUNT:
189 dentry = rpc_setup_pipedir_sb(sb, clnt);
190 if (!dentry)
191 return -ENOENT;
192 if (IS_ERR(dentry))
193 return PTR_ERR(dentry);
194 break;
195 case RPC_PIPEFS_UMOUNT:
196 __rpc_clnt_remove_pipedir(clnt);
197 break;
198 default:
199 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
200 return -ENOTSUPP;
201 }
202 return 0;
203}
204
205static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
206 struct super_block *sb)
207{
208 int error = 0;
209
210 for (;; clnt = clnt->cl_parent) {
211 if (!rpc_clnt_skip_event(clnt, event))
212 error = __rpc_clnt_handle_event(clnt, event, sb);
213 if (error || clnt == clnt->cl_parent)
214 break;
215 }
216 return error;
217}
218
219static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
220{
221 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
222 struct rpc_clnt *clnt;
223
224 spin_lock(&sn->rpc_client_lock);
225 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
226 if (rpc_clnt_skip_event(clnt, event))
227 continue;
228 spin_unlock(&sn->rpc_client_lock);
229 return clnt;
230 }
231 spin_unlock(&sn->rpc_client_lock);
232 return NULL;
233}
234
235static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
236 void *ptr)
237{
238 struct super_block *sb = ptr;
239 struct rpc_clnt *clnt;
240 int error = 0;
241
242 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
243 error = __rpc_pipefs_event(clnt, event, sb);
244 if (error)
245 break;
246 }
247 return error;
248}
249
250static struct notifier_block rpc_clients_block = {
251 .notifier_call = rpc_pipefs_event,
252 .priority = SUNRPC_PIPEFS_RPC_PRIO,
253};
254
255int rpc_clients_notifier_register(void)
256{
257 return rpc_pipefs_notifier_register(&rpc_clients_block);
258}
259
260void rpc_clients_notifier_unregister(void)
261{
262 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
263}
264
265static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
266 struct rpc_xprt *xprt,
267 const struct rpc_timeout *timeout)
268{
269 struct rpc_xprt *old;
270
271 spin_lock(&clnt->cl_lock);
272 old = rcu_dereference_protected(clnt->cl_xprt,
273 lockdep_is_held(&clnt->cl_lock));
274
275 if (!xprt_bound(xprt))
276 clnt->cl_autobind = 1;
277
278 clnt->cl_timeout = timeout;
279 rcu_assign_pointer(clnt->cl_xprt, xprt);
280 spin_unlock(&clnt->cl_lock);
281
282 return old;
283}
284
285static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
286{
287 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
288 nodename, sizeof(clnt->cl_nodename));
289}
290
291static int rpc_client_register(struct rpc_clnt *clnt,
292 rpc_authflavor_t pseudoflavor,
293 const char *client_name)
294{
295 struct rpc_auth_create_args auth_args = {
296 .pseudoflavor = pseudoflavor,
297 .target_name = client_name,
298 };
299 struct rpc_auth *auth;
300 struct net *net = rpc_net_ns(clnt);
301 struct super_block *pipefs_sb;
302 int err;
303
304 rpc_clnt_debugfs_register(clnt);
305
306 pipefs_sb = rpc_get_sb_net(net);
307 if (pipefs_sb) {
308 err = rpc_setup_pipedir(pipefs_sb, clnt);
309 if (err)
310 goto out;
311 }
312
313 rpc_register_client(clnt);
314 if (pipefs_sb)
315 rpc_put_sb_net(net);
316
317 auth = rpcauth_create(&auth_args, clnt);
318 if (IS_ERR(auth)) {
319 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
320 pseudoflavor);
321 err = PTR_ERR(auth);
322 goto err_auth;
323 }
324 return 0;
325err_auth:
326 pipefs_sb = rpc_get_sb_net(net);
327 rpc_unregister_client(clnt);
328 __rpc_clnt_remove_pipedir(clnt);
329out:
330 if (pipefs_sb)
331 rpc_put_sb_net(net);
332 rpc_sysfs_client_destroy(clnt);
333 rpc_clnt_debugfs_unregister(clnt);
334 return err;
335}
336
337static DEFINE_IDA(rpc_clids);
338
339void rpc_cleanup_clids(void)
340{
341 ida_destroy(&rpc_clids);
342}
343
344static int rpc_alloc_clid(struct rpc_clnt *clnt)
345{
346 int clid;
347
348 clid = ida_alloc(&rpc_clids, GFP_KERNEL);
349 if (clid < 0)
350 return clid;
351 clnt->cl_clid = clid;
352 return 0;
353}
354
355static void rpc_free_clid(struct rpc_clnt *clnt)
356{
357 ida_free(&rpc_clids, clnt->cl_clid);
358}
359
360static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
361 struct rpc_xprt_switch *xps,
362 struct rpc_xprt *xprt,
363 struct rpc_clnt *parent)
364{
365 const struct rpc_program *program = args->program;
366 const struct rpc_version *version;
367 struct rpc_clnt *clnt = NULL;
368 const struct rpc_timeout *timeout;
369 const char *nodename = args->nodename;
370 int err;
371
372 err = rpciod_up();
373 if (err)
374 goto out_no_rpciod;
375
376 err = -EINVAL;
377 if (args->version >= program->nrvers)
378 goto out_err;
379 version = program->version[args->version];
380 if (version == NULL)
381 goto out_err;
382
383 err = -ENOMEM;
384 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
385 if (!clnt)
386 goto out_err;
387 clnt->cl_parent = parent ? : clnt;
388
389 err = rpc_alloc_clid(clnt);
390 if (err)
391 goto out_no_clid;
392
393 clnt->cl_cred = get_cred(args->cred);
394 clnt->cl_procinfo = version->procs;
395 clnt->cl_maxproc = version->nrprocs;
396 clnt->cl_prog = args->prognumber ? : program->number;
397 clnt->cl_vers = version->number;
398 clnt->cl_stats = program->stats;
399 clnt->cl_metrics = rpc_alloc_iostats(clnt);
400 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
401 err = -ENOMEM;
402 if (clnt->cl_metrics == NULL)
403 goto out_no_stats;
404 clnt->cl_program = program;
405 INIT_LIST_HEAD(&clnt->cl_tasks);
406 spin_lock_init(&clnt->cl_lock);
407
408 timeout = xprt->timeout;
409 if (args->timeout != NULL) {
410 memcpy(&clnt->cl_timeout_default, args->timeout,
411 sizeof(clnt->cl_timeout_default));
412 timeout = &clnt->cl_timeout_default;
413 }
414
415 rpc_clnt_set_transport(clnt, xprt, timeout);
416 xprt->main = true;
417 xprt_iter_init(&clnt->cl_xpi, xps);
418 xprt_switch_put(xps);
419
420 clnt->cl_rtt = &clnt->cl_rtt_default;
421 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
422
423 refcount_set(&clnt->cl_count, 1);
424
425 if (nodename == NULL)
426 nodename = utsname()->nodename;
427 /* save the nodename */
428 rpc_clnt_set_nodename(clnt, nodename);
429
430 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
431 err = rpc_client_register(clnt, args->authflavor, args->client_name);
432 if (err)
433 goto out_no_path;
434 if (parent)
435 refcount_inc(&parent->cl_count);
436
437 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
438 return clnt;
439
440out_no_path:
441 rpc_free_iostats(clnt->cl_metrics);
442out_no_stats:
443 put_cred(clnt->cl_cred);
444 rpc_free_clid(clnt);
445out_no_clid:
446 kfree(clnt);
447out_err:
448 rpciod_down();
449out_no_rpciod:
450 xprt_switch_put(xps);
451 xprt_put(xprt);
452 trace_rpc_clnt_new_err(program->name, args->servername, err);
453 return ERR_PTR(err);
454}
455
456static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
457 struct rpc_xprt *xprt)
458{
459 struct rpc_clnt *clnt = NULL;
460 struct rpc_xprt_switch *xps;
461
462 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
463 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
464 xps = args->bc_xprt->xpt_bc_xps;
465 xprt_switch_get(xps);
466 } else {
467 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
468 if (xps == NULL) {
469 xprt_put(xprt);
470 return ERR_PTR(-ENOMEM);
471 }
472 if (xprt->bc_xprt) {
473 xprt_switch_get(xps);
474 xprt->bc_xprt->xpt_bc_xps = xps;
475 }
476 }
477 clnt = rpc_new_client(args, xps, xprt, NULL);
478 if (IS_ERR(clnt))
479 return clnt;
480
481 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
482 int err = rpc_ping(clnt);
483 if (err != 0) {
484 rpc_shutdown_client(clnt);
485 return ERR_PTR(err);
486 }
487 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
488 int err = rpc_ping_noreply(clnt);
489 if (err != 0) {
490 rpc_shutdown_client(clnt);
491 return ERR_PTR(err);
492 }
493 }
494
495 clnt->cl_softrtry = 1;
496 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
497 clnt->cl_softrtry = 0;
498 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
499 clnt->cl_softerr = 1;
500 }
501
502 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
503 clnt->cl_autobind = 1;
504 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
505 clnt->cl_noretranstimeo = 1;
506 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
507 clnt->cl_discrtry = 1;
508 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
509 clnt->cl_chatty = 1;
510
511 return clnt;
512}
513
514/**
515 * rpc_create - create an RPC client and transport with one call
516 * @args: rpc_clnt create argument structure
517 *
518 * Creates and initializes an RPC transport and an RPC client.
519 *
520 * It can ping the server in order to determine if it is up, and to see if
521 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
522 * this behavior so asynchronous tasks can also use rpc_create.
523 */
524struct rpc_clnt *rpc_create(struct rpc_create_args *args)
525{
526 struct rpc_xprt *xprt;
527 struct xprt_create xprtargs = {
528 .net = args->net,
529 .ident = args->protocol,
530 .srcaddr = args->saddress,
531 .dstaddr = args->address,
532 .addrlen = args->addrsize,
533 .servername = args->servername,
534 .bc_xprt = args->bc_xprt,
535 };
536 char servername[48];
537 struct rpc_clnt *clnt;
538 int i;
539
540 if (args->bc_xprt) {
541 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
542 xprt = args->bc_xprt->xpt_bc_xprt;
543 if (xprt) {
544 xprt_get(xprt);
545 return rpc_create_xprt(args, xprt);
546 }
547 }
548
549 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
550 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
551 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
552 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
553 /*
554 * If the caller chooses not to specify a hostname, whip
555 * up a string representation of the passed-in address.
556 */
557 if (xprtargs.servername == NULL) {
558 struct sockaddr_un *sun =
559 (struct sockaddr_un *)args->address;
560 struct sockaddr_in *sin =
561 (struct sockaddr_in *)args->address;
562 struct sockaddr_in6 *sin6 =
563 (struct sockaddr_in6 *)args->address;
564
565 servername[0] = '\0';
566 switch (args->address->sa_family) {
567 case AF_LOCAL:
568 snprintf(servername, sizeof(servername), "%s",
569 sun->sun_path);
570 break;
571 case AF_INET:
572 snprintf(servername, sizeof(servername), "%pI4",
573 &sin->sin_addr.s_addr);
574 break;
575 case AF_INET6:
576 snprintf(servername, sizeof(servername), "%pI6",
577 &sin6->sin6_addr);
578 break;
579 default:
580 /* caller wants default server name, but
581 * address family isn't recognized. */
582 return ERR_PTR(-EINVAL);
583 }
584 xprtargs.servername = servername;
585 }
586
587 xprt = xprt_create_transport(&xprtargs);
588 if (IS_ERR(xprt))
589 return (struct rpc_clnt *)xprt;
590
591 /*
592 * By default, kernel RPC client connects from a reserved port.
593 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
594 * but it is always enabled for rpciod, which handles the connect
595 * operation.
596 */
597 xprt->resvport = 1;
598 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
599 xprt->resvport = 0;
600 xprt->reuseport = 0;
601 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
602 xprt->reuseport = 1;
603
604 clnt = rpc_create_xprt(args, xprt);
605 if (IS_ERR(clnt) || args->nconnect <= 1)
606 return clnt;
607
608 for (i = 0; i < args->nconnect - 1; i++) {
609 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
610 break;
611 }
612 return clnt;
613}
614EXPORT_SYMBOL_GPL(rpc_create);
615
616/*
617 * This function clones the RPC client structure. It allows us to share the
618 * same transport while varying parameters such as the authentication
619 * flavour.
620 */
621static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
622 struct rpc_clnt *clnt)
623{
624 struct rpc_xprt_switch *xps;
625 struct rpc_xprt *xprt;
626 struct rpc_clnt *new;
627 int err;
628
629 err = -ENOMEM;
630 rcu_read_lock();
631 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
632 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
633 rcu_read_unlock();
634 if (xprt == NULL || xps == NULL) {
635 xprt_put(xprt);
636 xprt_switch_put(xps);
637 goto out_err;
638 }
639 args->servername = xprt->servername;
640 args->nodename = clnt->cl_nodename;
641
642 new = rpc_new_client(args, xps, xprt, clnt);
643 if (IS_ERR(new))
644 return new;
645
646 /* Turn off autobind on clones */
647 new->cl_autobind = 0;
648 new->cl_softrtry = clnt->cl_softrtry;
649 new->cl_softerr = clnt->cl_softerr;
650 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
651 new->cl_discrtry = clnt->cl_discrtry;
652 new->cl_chatty = clnt->cl_chatty;
653 new->cl_principal = clnt->cl_principal;
654 new->cl_max_connect = clnt->cl_max_connect;
655 return new;
656
657out_err:
658 trace_rpc_clnt_clone_err(clnt, err);
659 return ERR_PTR(err);
660}
661
662/**
663 * rpc_clone_client - Clone an RPC client structure
664 *
665 * @clnt: RPC client whose parameters are copied
666 *
667 * Returns a fresh RPC client or an ERR_PTR.
668 */
669struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
670{
671 struct rpc_create_args args = {
672 .program = clnt->cl_program,
673 .prognumber = clnt->cl_prog,
674 .version = clnt->cl_vers,
675 .authflavor = clnt->cl_auth->au_flavor,
676 .cred = clnt->cl_cred,
677 };
678 return __rpc_clone_client(&args, clnt);
679}
680EXPORT_SYMBOL_GPL(rpc_clone_client);
681
682/**
683 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
684 *
685 * @clnt: RPC client whose parameters are copied
686 * @flavor: security flavor for new client
687 *
688 * Returns a fresh RPC client or an ERR_PTR.
689 */
690struct rpc_clnt *
691rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
692{
693 struct rpc_create_args args = {
694 .program = clnt->cl_program,
695 .prognumber = clnt->cl_prog,
696 .version = clnt->cl_vers,
697 .authflavor = flavor,
698 .cred = clnt->cl_cred,
699 };
700 return __rpc_clone_client(&args, clnt);
701}
702EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
703
704/**
705 * rpc_switch_client_transport: switch the RPC transport on the fly
706 * @clnt: pointer to a struct rpc_clnt
707 * @args: pointer to the new transport arguments
708 * @timeout: pointer to the new timeout parameters
709 *
710 * This function allows the caller to switch the RPC transport for the
711 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
712 * server, for instance. It assumes that the caller has ensured that
713 * there are no active RPC tasks by using some form of locking.
714 *
715 * Returns zero if "clnt" is now using the new xprt. Otherwise a
716 * negative errno is returned, and "clnt" continues to use the old
717 * xprt.
718 */
719int rpc_switch_client_transport(struct rpc_clnt *clnt,
720 struct xprt_create *args,
721 const struct rpc_timeout *timeout)
722{
723 const struct rpc_timeout *old_timeo;
724 rpc_authflavor_t pseudoflavor;
725 struct rpc_xprt_switch *xps, *oldxps;
726 struct rpc_xprt *xprt, *old;
727 struct rpc_clnt *parent;
728 int err;
729
730 xprt = xprt_create_transport(args);
731 if (IS_ERR(xprt))
732 return PTR_ERR(xprt);
733
734 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
735 if (xps == NULL) {
736 xprt_put(xprt);
737 return -ENOMEM;
738 }
739
740 pseudoflavor = clnt->cl_auth->au_flavor;
741
742 old_timeo = clnt->cl_timeout;
743 old = rpc_clnt_set_transport(clnt, xprt, timeout);
744 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
745
746 rpc_unregister_client(clnt);
747 __rpc_clnt_remove_pipedir(clnt);
748 rpc_sysfs_client_destroy(clnt);
749 rpc_clnt_debugfs_unregister(clnt);
750
751 /*
752 * A new transport was created. "clnt" therefore
753 * becomes the root of a new cl_parent tree. clnt's
754 * children, if it has any, still point to the old xprt.
755 */
756 parent = clnt->cl_parent;
757 clnt->cl_parent = clnt;
758
759 /*
760 * The old rpc_auth cache cannot be re-used. GSS
761 * contexts in particular are between a single
762 * client and server.
763 */
764 err = rpc_client_register(clnt, pseudoflavor, NULL);
765 if (err)
766 goto out_revert;
767
768 synchronize_rcu();
769 if (parent != clnt)
770 rpc_release_client(parent);
771 xprt_switch_put(oldxps);
772 xprt_put(old);
773 trace_rpc_clnt_replace_xprt(clnt);
774 return 0;
775
776out_revert:
777 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
778 rpc_clnt_set_transport(clnt, old, old_timeo);
779 clnt->cl_parent = parent;
780 rpc_client_register(clnt, pseudoflavor, NULL);
781 xprt_switch_put(xps);
782 xprt_put(xprt);
783 trace_rpc_clnt_replace_xprt_err(clnt);
784 return err;
785}
786EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
787
788static
789int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
790 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
791{
792 struct rpc_xprt_switch *xps;
793
794 rcu_read_lock();
795 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
796 rcu_read_unlock();
797 if (xps == NULL)
798 return -EAGAIN;
799 func(xpi, xps);
800 xprt_switch_put(xps);
801 return 0;
802}
803
804static
805int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
806{
807 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
808}
809
810static
811int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
812 struct rpc_xprt_iter *xpi)
813{
814 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
815}
816
817/**
818 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
819 * @clnt: pointer to client
820 * @fn: function to apply
821 * @data: void pointer to function data
822 *
823 * Iterates through the list of RPC transports currently attached to the
824 * client and applies the function fn(clnt, xprt, data).
825 *
826 * On error, the iteration stops, and the function returns the error value.
827 */
828int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
829 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
830 void *data)
831{
832 struct rpc_xprt_iter xpi;
833 int ret;
834
835 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
836 if (ret)
837 return ret;
838 for (;;) {
839 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
840
841 if (!xprt)
842 break;
843 ret = fn(clnt, xprt, data);
844 xprt_put(xprt);
845 if (ret < 0)
846 break;
847 }
848 xprt_iter_destroy(&xpi);
849 return ret;
850}
851EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
852
853/*
854 * Kill all tasks for the given client.
855 * XXX: kill their descendants as well?
856 */
857void rpc_killall_tasks(struct rpc_clnt *clnt)
858{
859 struct rpc_task *rovr;
860
861
862 if (list_empty(&clnt->cl_tasks))
863 return;
864
865 /*
866 * Spin lock all_tasks to prevent changes...
867 */
868 trace_rpc_clnt_killall(clnt);
869 spin_lock(&clnt->cl_lock);
870 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
871 rpc_signal_task(rovr);
872 spin_unlock(&clnt->cl_lock);
873}
874EXPORT_SYMBOL_GPL(rpc_killall_tasks);
875
876/**
877 * rpc_cancel_tasks - try to cancel a set of RPC tasks
878 * @clnt: Pointer to RPC client
879 * @error: RPC task error value to set
880 * @fnmatch: Pointer to selector function
881 * @data: User data
882 *
883 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
884 * The argument @error must be a negative error value.
885 */
886unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
887 bool (*fnmatch)(const struct rpc_task *,
888 const void *),
889 const void *data)
890{
891 struct rpc_task *task;
892 unsigned long count = 0;
893
894 if (list_empty(&clnt->cl_tasks))
895 return 0;
896 /*
897 * Spin lock all_tasks to prevent changes...
898 */
899 spin_lock(&clnt->cl_lock);
900 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
901 if (!RPC_IS_ACTIVATED(task))
902 continue;
903 if (!fnmatch(task, data))
904 continue;
905 rpc_task_try_cancel(task, error);
906 count++;
907 }
908 spin_unlock(&clnt->cl_lock);
909 return count;
910}
911EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
912
913static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
914 struct rpc_xprt *xprt, void *dummy)
915{
916 if (xprt_connected(xprt))
917 xprt_force_disconnect(xprt);
918 return 0;
919}
920
921void rpc_clnt_disconnect(struct rpc_clnt *clnt)
922{
923 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
924}
925EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
926
927/*
928 * Properly shut down an RPC client, terminating all outstanding
929 * requests.
930 */
931void rpc_shutdown_client(struct rpc_clnt *clnt)
932{
933 might_sleep();
934
935 trace_rpc_clnt_shutdown(clnt);
936
937 while (!list_empty(&clnt->cl_tasks)) {
938 rpc_killall_tasks(clnt);
939 wait_event_timeout(destroy_wait,
940 list_empty(&clnt->cl_tasks), 1*HZ);
941 }
942
943 rpc_release_client(clnt);
944}
945EXPORT_SYMBOL_GPL(rpc_shutdown_client);
946
947/*
948 * Free an RPC client
949 */
950static void rpc_free_client_work(struct work_struct *work)
951{
952 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
953
954 trace_rpc_clnt_free(clnt);
955
956 /* These might block on processes that might allocate memory,
957 * so they cannot be called in rpciod, so they are handled separately
958 * here.
959 */
960 rpc_sysfs_client_destroy(clnt);
961 rpc_clnt_debugfs_unregister(clnt);
962 rpc_free_clid(clnt);
963 rpc_clnt_remove_pipedir(clnt);
964 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
965
966 kfree(clnt);
967 rpciod_down();
968}
969static struct rpc_clnt *
970rpc_free_client(struct rpc_clnt *clnt)
971{
972 struct rpc_clnt *parent = NULL;
973
974 trace_rpc_clnt_release(clnt);
975 if (clnt->cl_parent != clnt)
976 parent = clnt->cl_parent;
977 rpc_unregister_client(clnt);
978 rpc_free_iostats(clnt->cl_metrics);
979 clnt->cl_metrics = NULL;
980 xprt_iter_destroy(&clnt->cl_xpi);
981 put_cred(clnt->cl_cred);
982
983 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
984 schedule_work(&clnt->cl_work);
985 return parent;
986}
987
988/*
989 * Free an RPC client
990 */
991static struct rpc_clnt *
992rpc_free_auth(struct rpc_clnt *clnt)
993{
994 /*
995 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
996 * release remaining GSS contexts. This mechanism ensures
997 * that it can do so safely.
998 */
999 if (clnt->cl_auth != NULL) {
1000 rpcauth_release(clnt->cl_auth);
1001 clnt->cl_auth = NULL;
1002 }
1003 if (refcount_dec_and_test(&clnt->cl_count))
1004 return rpc_free_client(clnt);
1005 return NULL;
1006}
1007
1008/*
1009 * Release reference to the RPC client
1010 */
1011void
1012rpc_release_client(struct rpc_clnt *clnt)
1013{
1014 do {
1015 if (list_empty(&clnt->cl_tasks))
1016 wake_up(&destroy_wait);
1017 if (refcount_dec_not_one(&clnt->cl_count))
1018 break;
1019 clnt = rpc_free_auth(clnt);
1020 } while (clnt != NULL);
1021}
1022EXPORT_SYMBOL_GPL(rpc_release_client);
1023
1024/**
1025 * rpc_bind_new_program - bind a new RPC program to an existing client
1026 * @old: old rpc_client
1027 * @program: rpc program to set
1028 * @vers: rpc program version
1029 *
1030 * Clones the rpc client and sets up a new RPC program. This is mainly
1031 * of use for enabling different RPC programs to share the same transport.
1032 * The Sun NFSv2/v3 ACL protocol can do this.
1033 */
1034struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1035 const struct rpc_program *program,
1036 u32 vers)
1037{
1038 struct rpc_create_args args = {
1039 .program = program,
1040 .prognumber = program->number,
1041 .version = vers,
1042 .authflavor = old->cl_auth->au_flavor,
1043 .cred = old->cl_cred,
1044 };
1045 struct rpc_clnt *clnt;
1046 int err;
1047
1048 clnt = __rpc_clone_client(&args, old);
1049 if (IS_ERR(clnt))
1050 goto out;
1051 err = rpc_ping(clnt);
1052 if (err != 0) {
1053 rpc_shutdown_client(clnt);
1054 clnt = ERR_PTR(err);
1055 }
1056out:
1057 return clnt;
1058}
1059EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1060
1061struct rpc_xprt *
1062rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1063{
1064 struct rpc_xprt_switch *xps;
1065
1066 if (!xprt)
1067 return NULL;
1068 rcu_read_lock();
1069 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1070 atomic_long_inc(&xps->xps_queuelen);
1071 rcu_read_unlock();
1072 atomic_long_inc(&xprt->queuelen);
1073
1074 return xprt;
1075}
1076
1077static void
1078rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1079{
1080 struct rpc_xprt_switch *xps;
1081
1082 atomic_long_dec(&xprt->queuelen);
1083 rcu_read_lock();
1084 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1085 atomic_long_dec(&xps->xps_queuelen);
1086 rcu_read_unlock();
1087
1088 xprt_put(xprt);
1089}
1090
1091void rpc_task_release_transport(struct rpc_task *task)
1092{
1093 struct rpc_xprt *xprt = task->tk_xprt;
1094
1095 if (xprt) {
1096 task->tk_xprt = NULL;
1097 if (task->tk_client)
1098 rpc_task_release_xprt(task->tk_client, xprt);
1099 else
1100 xprt_put(xprt);
1101 }
1102}
1103EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1104
1105void rpc_task_release_client(struct rpc_task *task)
1106{
1107 struct rpc_clnt *clnt = task->tk_client;
1108
1109 rpc_task_release_transport(task);
1110 if (clnt != NULL) {
1111 /* Remove from client task list */
1112 spin_lock(&clnt->cl_lock);
1113 list_del(&task->tk_task);
1114 spin_unlock(&clnt->cl_lock);
1115 task->tk_client = NULL;
1116
1117 rpc_release_client(clnt);
1118 }
1119}
1120
1121static struct rpc_xprt *
1122rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1123{
1124 struct rpc_xprt *xprt;
1125
1126 rcu_read_lock();
1127 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1128 rcu_read_unlock();
1129 return rpc_task_get_xprt(clnt, xprt);
1130}
1131
1132static struct rpc_xprt *
1133rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1134{
1135 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1136}
1137
1138static
1139void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1140{
1141 if (task->tk_xprt) {
1142 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1143 (task->tk_flags & RPC_TASK_MOVEABLE)))
1144 return;
1145 xprt_release(task);
1146 xprt_put(task->tk_xprt);
1147 }
1148 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1149 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1150 else
1151 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1152}
1153
1154static
1155void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1156{
1157 rpc_task_set_transport(task, clnt);
1158 task->tk_client = clnt;
1159 refcount_inc(&clnt->cl_count);
1160 if (clnt->cl_softrtry)
1161 task->tk_flags |= RPC_TASK_SOFT;
1162 if (clnt->cl_softerr)
1163 task->tk_flags |= RPC_TASK_TIMEOUT;
1164 if (clnt->cl_noretranstimeo)
1165 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1166 /* Add to the client's list of all tasks */
1167 spin_lock(&clnt->cl_lock);
1168 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1169 spin_unlock(&clnt->cl_lock);
1170}
1171
1172static void
1173rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1174{
1175 if (msg != NULL) {
1176 task->tk_msg.rpc_proc = msg->rpc_proc;
1177 task->tk_msg.rpc_argp = msg->rpc_argp;
1178 task->tk_msg.rpc_resp = msg->rpc_resp;
1179 task->tk_msg.rpc_cred = msg->rpc_cred;
1180 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1181 get_cred(task->tk_msg.rpc_cred);
1182 }
1183}
1184
1185/*
1186 * Default callback for async RPC calls
1187 */
1188static void
1189rpc_default_callback(struct rpc_task *task, void *data)
1190{
1191}
1192
1193static const struct rpc_call_ops rpc_default_ops = {
1194 .rpc_call_done = rpc_default_callback,
1195};
1196
1197/**
1198 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1199 * @task_setup_data: pointer to task initialisation data
1200 */
1201struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1202{
1203 struct rpc_task *task;
1204
1205 task = rpc_new_task(task_setup_data);
1206 if (IS_ERR(task))
1207 return task;
1208
1209 if (!RPC_IS_ASYNC(task))
1210 task->tk_flags |= RPC_TASK_CRED_NOREF;
1211
1212 rpc_task_set_client(task, task_setup_data->rpc_client);
1213 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1214
1215 if (task->tk_action == NULL)
1216 rpc_call_start(task);
1217
1218 atomic_inc(&task->tk_count);
1219 rpc_execute(task);
1220 return task;
1221}
1222EXPORT_SYMBOL_GPL(rpc_run_task);
1223
1224/**
1225 * rpc_call_sync - Perform a synchronous RPC call
1226 * @clnt: pointer to RPC client
1227 * @msg: RPC call parameters
1228 * @flags: RPC call flags
1229 */
1230int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1231{
1232 struct rpc_task *task;
1233 struct rpc_task_setup task_setup_data = {
1234 .rpc_client = clnt,
1235 .rpc_message = msg,
1236 .callback_ops = &rpc_default_ops,
1237 .flags = flags,
1238 };
1239 int status;
1240
1241 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1242 if (flags & RPC_TASK_ASYNC) {
1243 rpc_release_calldata(task_setup_data.callback_ops,
1244 task_setup_data.callback_data);
1245 return -EINVAL;
1246 }
1247
1248 task = rpc_run_task(&task_setup_data);
1249 if (IS_ERR(task))
1250 return PTR_ERR(task);
1251 status = task->tk_status;
1252 rpc_put_task(task);
1253 return status;
1254}
1255EXPORT_SYMBOL_GPL(rpc_call_sync);
1256
1257/**
1258 * rpc_call_async - Perform an asynchronous RPC call
1259 * @clnt: pointer to RPC client
1260 * @msg: RPC call parameters
1261 * @flags: RPC call flags
1262 * @tk_ops: RPC call ops
1263 * @data: user call data
1264 */
1265int
1266rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1267 const struct rpc_call_ops *tk_ops, void *data)
1268{
1269 struct rpc_task *task;
1270 struct rpc_task_setup task_setup_data = {
1271 .rpc_client = clnt,
1272 .rpc_message = msg,
1273 .callback_ops = tk_ops,
1274 .callback_data = data,
1275 .flags = flags|RPC_TASK_ASYNC,
1276 };
1277
1278 task = rpc_run_task(&task_setup_data);
1279 if (IS_ERR(task))
1280 return PTR_ERR(task);
1281 rpc_put_task(task);
1282 return 0;
1283}
1284EXPORT_SYMBOL_GPL(rpc_call_async);
1285
1286#if defined(CONFIG_SUNRPC_BACKCHANNEL)
1287static void call_bc_encode(struct rpc_task *task);
1288
1289/**
1290 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1291 * rpc_execute against it
1292 * @req: RPC request
1293 */
1294struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1295{
1296 struct rpc_task *task;
1297 struct rpc_task_setup task_setup_data = {
1298 .callback_ops = &rpc_default_ops,
1299 .flags = RPC_TASK_SOFTCONN |
1300 RPC_TASK_NO_RETRANS_TIMEOUT,
1301 };
1302
1303 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1304 /*
1305 * Create an rpc_task to send the data
1306 */
1307 task = rpc_new_task(&task_setup_data);
1308 if (IS_ERR(task)) {
1309 xprt_free_bc_request(req);
1310 return task;
1311 }
1312
1313 xprt_init_bc_request(req, task);
1314
1315 task->tk_action = call_bc_encode;
1316 atomic_inc(&task->tk_count);
1317 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1318 rpc_execute(task);
1319
1320 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1321 return task;
1322}
1323#endif /* CONFIG_SUNRPC_BACKCHANNEL */
1324
1325/**
1326 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1327 * @req: RPC request to prepare
1328 * @pages: vector of struct page pointers
1329 * @base: offset in first page where receive should start, in bytes
1330 * @len: expected size of the upper layer data payload, in bytes
1331 * @hdrsize: expected size of upper layer reply header, in XDR words
1332 *
1333 */
1334void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1335 unsigned int base, unsigned int len,
1336 unsigned int hdrsize)
1337{
1338 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1339
1340 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1341 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1342}
1343EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1344
1345void
1346rpc_call_start(struct rpc_task *task)
1347{
1348 task->tk_action = call_start;
1349}
1350EXPORT_SYMBOL_GPL(rpc_call_start);
1351
1352/**
1353 * rpc_peeraddr - extract remote peer address from clnt's xprt
1354 * @clnt: RPC client structure
1355 * @buf: target buffer
1356 * @bufsize: length of target buffer
1357 *
1358 * Returns the number of bytes that are actually in the stored address.
1359 */
1360size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1361{
1362 size_t bytes;
1363 struct rpc_xprt *xprt;
1364
1365 rcu_read_lock();
1366 xprt = rcu_dereference(clnt->cl_xprt);
1367
1368 bytes = xprt->addrlen;
1369 if (bytes > bufsize)
1370 bytes = bufsize;
1371 memcpy(buf, &xprt->addr, bytes);
1372 rcu_read_unlock();
1373
1374 return bytes;
1375}
1376EXPORT_SYMBOL_GPL(rpc_peeraddr);
1377
1378/**
1379 * rpc_peeraddr2str - return remote peer address in printable format
1380 * @clnt: RPC client structure
1381 * @format: address format
1382 *
1383 * NB: the lifetime of the memory referenced by the returned pointer is
1384 * the same as the rpc_xprt itself. As long as the caller uses this
1385 * pointer, it must hold the RCU read lock.
1386 */
1387const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1388 enum rpc_display_format_t format)
1389{
1390 struct rpc_xprt *xprt;
1391
1392 xprt = rcu_dereference(clnt->cl_xprt);
1393
1394 if (xprt->address_strings[format] != NULL)
1395 return xprt->address_strings[format];
1396 else
1397 return "unprintable";
1398}
1399EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1400
1401static const struct sockaddr_in rpc_inaddr_loopback = {
1402 .sin_family = AF_INET,
1403 .sin_addr.s_addr = htonl(INADDR_ANY),
1404};
1405
1406static const struct sockaddr_in6 rpc_in6addr_loopback = {
1407 .sin6_family = AF_INET6,
1408 .sin6_addr = IN6ADDR_ANY_INIT,
1409};
1410
1411/*
1412 * Try a getsockname() on a connected datagram socket. Using a
1413 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1414 * This conserves the ephemeral port number space.
1415 *
1416 * Returns zero and fills in "buf" if successful; otherwise, a
1417 * negative errno is returned.
1418 */
1419static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1420 struct sockaddr *buf)
1421{
1422 struct socket *sock;
1423 int err;
1424
1425 err = __sock_create(net, sap->sa_family,
1426 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1427 if (err < 0) {
1428 dprintk("RPC: can't create UDP socket (%d)\n", err);
1429 goto out;
1430 }
1431
1432 switch (sap->sa_family) {
1433 case AF_INET:
1434 err = kernel_bind(sock,
1435 (struct sockaddr *)&rpc_inaddr_loopback,
1436 sizeof(rpc_inaddr_loopback));
1437 break;
1438 case AF_INET6:
1439 err = kernel_bind(sock,
1440 (struct sockaddr *)&rpc_in6addr_loopback,
1441 sizeof(rpc_in6addr_loopback));
1442 break;
1443 default:
1444 err = -EAFNOSUPPORT;
1445 goto out_release;
1446 }
1447 if (err < 0) {
1448 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1449 goto out_release;
1450 }
1451
1452 err = kernel_connect(sock, sap, salen, 0);
1453 if (err < 0) {
1454 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1455 goto out_release;
1456 }
1457
1458 err = kernel_getsockname(sock, buf);
1459 if (err < 0) {
1460 dprintk("RPC: getsockname failed (%d)\n", err);
1461 goto out_release;
1462 }
1463
1464 err = 0;
1465 if (buf->sa_family == AF_INET6) {
1466 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1467 sin6->sin6_scope_id = 0;
1468 }
1469 dprintk("RPC: %s succeeded\n", __func__);
1470
1471out_release:
1472 sock_release(sock);
1473out:
1474 return err;
1475}
1476
1477/*
1478 * Scraping a connected socket failed, so we don't have a useable
1479 * local address. Fallback: generate an address that will prevent
1480 * the server from calling us back.
1481 *
1482 * Returns zero and fills in "buf" if successful; otherwise, a
1483 * negative errno is returned.
1484 */
1485static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1486{
1487 switch (family) {
1488 case AF_INET:
1489 if (buflen < sizeof(rpc_inaddr_loopback))
1490 return -EINVAL;
1491 memcpy(buf, &rpc_inaddr_loopback,
1492 sizeof(rpc_inaddr_loopback));
1493 break;
1494 case AF_INET6:
1495 if (buflen < sizeof(rpc_in6addr_loopback))
1496 return -EINVAL;
1497 memcpy(buf, &rpc_in6addr_loopback,
1498 sizeof(rpc_in6addr_loopback));
1499 break;
1500 default:
1501 dprintk("RPC: %s: address family not supported\n",
1502 __func__);
1503 return -EAFNOSUPPORT;
1504 }
1505 dprintk("RPC: %s: succeeded\n", __func__);
1506 return 0;
1507}
1508
1509/**
1510 * rpc_localaddr - discover local endpoint address for an RPC client
1511 * @clnt: RPC client structure
1512 * @buf: target buffer
1513 * @buflen: size of target buffer, in bytes
1514 *
1515 * Returns zero and fills in "buf" and "buflen" if successful;
1516 * otherwise, a negative errno is returned.
1517 *
1518 * This works even if the underlying transport is not currently connected,
1519 * or if the upper layer never previously provided a source address.
1520 *
1521 * The result of this function call is transient: multiple calls in
1522 * succession may give different results, depending on how local
1523 * networking configuration changes over time.
1524 */
1525int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1526{
1527 struct sockaddr_storage address;
1528 struct sockaddr *sap = (struct sockaddr *)&address;
1529 struct rpc_xprt *xprt;
1530 struct net *net;
1531 size_t salen;
1532 int err;
1533
1534 rcu_read_lock();
1535 xprt = rcu_dereference(clnt->cl_xprt);
1536 salen = xprt->addrlen;
1537 memcpy(sap, &xprt->addr, salen);
1538 net = get_net(xprt->xprt_net);
1539 rcu_read_unlock();
1540
1541 rpc_set_port(sap, 0);
1542 err = rpc_sockname(net, sap, salen, buf);
1543 put_net(net);
1544 if (err != 0)
1545 /* Couldn't discover local address, return ANYADDR */
1546 return rpc_anyaddr(sap->sa_family, buf, buflen);
1547 return 0;
1548}
1549EXPORT_SYMBOL_GPL(rpc_localaddr);
1550
1551void
1552rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1553{
1554 struct rpc_xprt *xprt;
1555
1556 rcu_read_lock();
1557 xprt = rcu_dereference(clnt->cl_xprt);
1558 if (xprt->ops->set_buffer_size)
1559 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1560 rcu_read_unlock();
1561}
1562EXPORT_SYMBOL_GPL(rpc_setbufsize);
1563
1564/**
1565 * rpc_net_ns - Get the network namespace for this RPC client
1566 * @clnt: RPC client to query
1567 *
1568 */
1569struct net *rpc_net_ns(struct rpc_clnt *clnt)
1570{
1571 struct net *ret;
1572
1573 rcu_read_lock();
1574 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1575 rcu_read_unlock();
1576 return ret;
1577}
1578EXPORT_SYMBOL_GPL(rpc_net_ns);
1579
1580/**
1581 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1582 * @clnt: RPC client to query
1583 *
1584 * For stream transports, this is one RPC record fragment (see RFC
1585 * 1831), as we don't support multi-record requests yet. For datagram
1586 * transports, this is the size of an IP packet minus the IP, UDP, and
1587 * RPC header sizes.
1588 */
1589size_t rpc_max_payload(struct rpc_clnt *clnt)
1590{
1591 size_t ret;
1592
1593 rcu_read_lock();
1594 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1595 rcu_read_unlock();
1596 return ret;
1597}
1598EXPORT_SYMBOL_GPL(rpc_max_payload);
1599
1600/**
1601 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1602 * @clnt: RPC client to query
1603 */
1604size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1605{
1606 struct rpc_xprt *xprt;
1607 size_t ret;
1608
1609 rcu_read_lock();
1610 xprt = rcu_dereference(clnt->cl_xprt);
1611 ret = xprt->ops->bc_maxpayload(xprt);
1612 rcu_read_unlock();
1613 return ret;
1614}
1615EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1616
1617unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1618{
1619 struct rpc_xprt *xprt;
1620 unsigned int ret;
1621
1622 rcu_read_lock();
1623 xprt = rcu_dereference(clnt->cl_xprt);
1624 ret = xprt->ops->bc_num_slots(xprt);
1625 rcu_read_unlock();
1626 return ret;
1627}
1628EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1629
1630/**
1631 * rpc_force_rebind - force transport to check that remote port is unchanged
1632 * @clnt: client to rebind
1633 *
1634 */
1635void rpc_force_rebind(struct rpc_clnt *clnt)
1636{
1637 if (clnt->cl_autobind) {
1638 rcu_read_lock();
1639 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1640 rcu_read_unlock();
1641 }
1642}
1643EXPORT_SYMBOL_GPL(rpc_force_rebind);
1644
1645static int
1646__rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1647{
1648 task->tk_status = 0;
1649 task->tk_rpc_status = 0;
1650 task->tk_action = action;
1651 return 1;
1652}
1653
1654/*
1655 * Restart an (async) RPC call. Usually called from within the
1656 * exit handler.
1657 */
1658int
1659rpc_restart_call(struct rpc_task *task)
1660{
1661 return __rpc_restart_call(task, call_start);
1662}
1663EXPORT_SYMBOL_GPL(rpc_restart_call);
1664
1665/*
1666 * Restart an (async) RPC call from the call_prepare state.
1667 * Usually called from within the exit handler.
1668 */
1669int
1670rpc_restart_call_prepare(struct rpc_task *task)
1671{
1672 if (task->tk_ops->rpc_call_prepare != NULL)
1673 return __rpc_restart_call(task, rpc_prepare_task);
1674 return rpc_restart_call(task);
1675}
1676EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1677
1678const char
1679*rpc_proc_name(const struct rpc_task *task)
1680{
1681 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1682
1683 if (proc) {
1684 if (proc->p_name)
1685 return proc->p_name;
1686 else
1687 return "NULL";
1688 } else
1689 return "no proc";
1690}
1691
1692static void
1693__rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1694{
1695 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1696 rpc_task_set_rpc_status(task, rpc_status);
1697 rpc_exit(task, tk_status);
1698}
1699
1700static void
1701rpc_call_rpcerror(struct rpc_task *task, int status)
1702{
1703 __rpc_call_rpcerror(task, status, status);
1704}
1705
1706/*
1707 * 0. Initial state
1708 *
1709 * Other FSM states can be visited zero or more times, but
1710 * this state is visited exactly once for each RPC.
1711 */
1712static void
1713call_start(struct rpc_task *task)
1714{
1715 struct rpc_clnt *clnt = task->tk_client;
1716 int idx = task->tk_msg.rpc_proc->p_statidx;
1717
1718 trace_rpc_request(task);
1719
1720 /* Increment call count (version might not be valid for ping) */
1721 if (clnt->cl_program->version[clnt->cl_vers])
1722 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1723 clnt->cl_stats->rpccnt++;
1724 task->tk_action = call_reserve;
1725 rpc_task_set_transport(task, clnt);
1726}
1727
1728/*
1729 * 1. Reserve an RPC call slot
1730 */
1731static void
1732call_reserve(struct rpc_task *task)
1733{
1734 task->tk_status = 0;
1735 task->tk_action = call_reserveresult;
1736 xprt_reserve(task);
1737}
1738
1739static void call_retry_reserve(struct rpc_task *task);
1740
1741/*
1742 * 1b. Grok the result of xprt_reserve()
1743 */
1744static void
1745call_reserveresult(struct rpc_task *task)
1746{
1747 int status = task->tk_status;
1748
1749 /*
1750 * After a call to xprt_reserve(), we must have either
1751 * a request slot or else an error status.
1752 */
1753 task->tk_status = 0;
1754 if (status >= 0) {
1755 if (task->tk_rqstp) {
1756 task->tk_action = call_refresh;
1757 return;
1758 }
1759
1760 rpc_call_rpcerror(task, -EIO);
1761 return;
1762 }
1763
1764 switch (status) {
1765 case -ENOMEM:
1766 rpc_delay(task, HZ >> 2);
1767 fallthrough;
1768 case -EAGAIN: /* woken up; retry */
1769 task->tk_action = call_retry_reserve;
1770 return;
1771 default:
1772 rpc_call_rpcerror(task, status);
1773 }
1774}
1775
1776/*
1777 * 1c. Retry reserving an RPC call slot
1778 */
1779static void
1780call_retry_reserve(struct rpc_task *task)
1781{
1782 task->tk_status = 0;
1783 task->tk_action = call_reserveresult;
1784 xprt_retry_reserve(task);
1785}
1786
1787/*
1788 * 2. Bind and/or refresh the credentials
1789 */
1790static void
1791call_refresh(struct rpc_task *task)
1792{
1793 task->tk_action = call_refreshresult;
1794 task->tk_status = 0;
1795 task->tk_client->cl_stats->rpcauthrefresh++;
1796 rpcauth_refreshcred(task);
1797}
1798
1799/*
1800 * 2a. Process the results of a credential refresh
1801 */
1802static void
1803call_refreshresult(struct rpc_task *task)
1804{
1805 int status = task->tk_status;
1806
1807 task->tk_status = 0;
1808 task->tk_action = call_refresh;
1809 switch (status) {
1810 case 0:
1811 if (rpcauth_uptodatecred(task)) {
1812 task->tk_action = call_allocate;
1813 return;
1814 }
1815 /* Use rate-limiting and a max number of retries if refresh
1816 * had status 0 but failed to update the cred.
1817 */
1818 fallthrough;
1819 case -ETIMEDOUT:
1820 rpc_delay(task, 3*HZ);
1821 fallthrough;
1822 case -EAGAIN:
1823 status = -EACCES;
1824 fallthrough;
1825 case -EKEYEXPIRED:
1826 if (!task->tk_cred_retry)
1827 break;
1828 task->tk_cred_retry--;
1829 trace_rpc_retry_refresh_status(task);
1830 return;
1831 case -ENOMEM:
1832 rpc_delay(task, HZ >> 4);
1833 return;
1834 }
1835 trace_rpc_refresh_status(task);
1836 rpc_call_rpcerror(task, status);
1837}
1838
1839/*
1840 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1841 * (Note: buffer memory is freed in xprt_release).
1842 */
1843static void
1844call_allocate(struct rpc_task *task)
1845{
1846 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1847 struct rpc_rqst *req = task->tk_rqstp;
1848 struct rpc_xprt *xprt = req->rq_xprt;
1849 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1850 int status;
1851
1852 task->tk_status = 0;
1853 task->tk_action = call_encode;
1854
1855 if (req->rq_buffer)
1856 return;
1857
1858 if (proc->p_proc != 0) {
1859 BUG_ON(proc->p_arglen == 0);
1860 if (proc->p_decode != NULL)
1861 BUG_ON(proc->p_replen == 0);
1862 }
1863
1864 /*
1865 * Calculate the size (in quads) of the RPC call
1866 * and reply headers, and convert both values
1867 * to byte sizes.
1868 */
1869 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1870 proc->p_arglen;
1871 req->rq_callsize <<= 2;
1872 /*
1873 * Note: the reply buffer must at minimum allocate enough space
1874 * for the 'struct accepted_reply' from RFC5531.
1875 */
1876 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1877 max_t(size_t, proc->p_replen, 2);
1878 req->rq_rcvsize <<= 2;
1879
1880 status = xprt->ops->buf_alloc(task);
1881 trace_rpc_buf_alloc(task, status);
1882 if (status == 0)
1883 return;
1884 if (status != -ENOMEM) {
1885 rpc_call_rpcerror(task, status);
1886 return;
1887 }
1888
1889 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1890 task->tk_action = call_allocate;
1891 rpc_delay(task, HZ>>4);
1892 return;
1893 }
1894
1895 rpc_call_rpcerror(task, -ERESTARTSYS);
1896}
1897
1898static int
1899rpc_task_need_encode(struct rpc_task *task)
1900{
1901 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1902 (!(task->tk_flags & RPC_TASK_SENT) ||
1903 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1904 xprt_request_need_retransmit(task));
1905}
1906
1907static void
1908rpc_xdr_encode(struct rpc_task *task)
1909{
1910 struct rpc_rqst *req = task->tk_rqstp;
1911 struct xdr_stream xdr;
1912
1913 xdr_buf_init(&req->rq_snd_buf,
1914 req->rq_buffer,
1915 req->rq_callsize);
1916 xdr_buf_init(&req->rq_rcv_buf,
1917 req->rq_rbuffer,
1918 req->rq_rcvsize);
1919
1920 req->rq_reply_bytes_recvd = 0;
1921 req->rq_snd_buf.head[0].iov_len = 0;
1922 xdr_init_encode(&xdr, &req->rq_snd_buf,
1923 req->rq_snd_buf.head[0].iov_base, req);
1924 if (rpc_encode_header(task, &xdr))
1925 return;
1926
1927 task->tk_status = rpcauth_wrap_req(task, &xdr);
1928}
1929
1930/*
1931 * 3. Encode arguments of an RPC call
1932 */
1933static void
1934call_encode(struct rpc_task *task)
1935{
1936 if (!rpc_task_need_encode(task))
1937 goto out;
1938
1939 /* Dequeue task from the receive queue while we're encoding */
1940 xprt_request_dequeue_xprt(task);
1941 /* Encode here so that rpcsec_gss can use correct sequence number. */
1942 rpc_xdr_encode(task);
1943 /* Add task to reply queue before transmission to avoid races */
1944 if (task->tk_status == 0 && rpc_reply_expected(task))
1945 task->tk_status = xprt_request_enqueue_receive(task);
1946 /* Did the encode result in an error condition? */
1947 if (task->tk_status != 0) {
1948 /* Was the error nonfatal? */
1949 switch (task->tk_status) {
1950 case -EAGAIN:
1951 case -ENOMEM:
1952 rpc_delay(task, HZ >> 4);
1953 break;
1954 case -EKEYEXPIRED:
1955 if (!task->tk_cred_retry) {
1956 rpc_call_rpcerror(task, task->tk_status);
1957 } else {
1958 task->tk_action = call_refresh;
1959 task->tk_cred_retry--;
1960 trace_rpc_retry_refresh_status(task);
1961 }
1962 break;
1963 default:
1964 rpc_call_rpcerror(task, task->tk_status);
1965 }
1966 return;
1967 }
1968
1969 xprt_request_enqueue_transmit(task);
1970out:
1971 task->tk_action = call_transmit;
1972 /* Check that the connection is OK */
1973 if (!xprt_bound(task->tk_xprt))
1974 task->tk_action = call_bind;
1975 else if (!xprt_connected(task->tk_xprt))
1976 task->tk_action = call_connect;
1977}
1978
1979/*
1980 * Helpers to check if the task was already transmitted, and
1981 * to take action when that is the case.
1982 */
1983static bool
1984rpc_task_transmitted(struct rpc_task *task)
1985{
1986 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1987}
1988
1989static void
1990rpc_task_handle_transmitted(struct rpc_task *task)
1991{
1992 xprt_end_transmit(task);
1993 task->tk_action = call_transmit_status;
1994}
1995
1996/*
1997 * 4. Get the server port number if not yet set
1998 */
1999static void
2000call_bind(struct rpc_task *task)
2001{
2002 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2003
2004 if (rpc_task_transmitted(task)) {
2005 rpc_task_handle_transmitted(task);
2006 return;
2007 }
2008
2009 if (xprt_bound(xprt)) {
2010 task->tk_action = call_connect;
2011 return;
2012 }
2013
2014 task->tk_action = call_bind_status;
2015 if (!xprt_prepare_transmit(task))
2016 return;
2017
2018 xprt->ops->rpcbind(task);
2019}
2020
2021/*
2022 * 4a. Sort out bind result
2023 */
2024static void
2025call_bind_status(struct rpc_task *task)
2026{
2027 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2028 int status = -EIO;
2029
2030 if (rpc_task_transmitted(task)) {
2031 rpc_task_handle_transmitted(task);
2032 return;
2033 }
2034
2035 if (task->tk_status >= 0)
2036 goto out_next;
2037 if (xprt_bound(xprt)) {
2038 task->tk_status = 0;
2039 goto out_next;
2040 }
2041
2042 switch (task->tk_status) {
2043 case -ENOMEM:
2044 rpc_delay(task, HZ >> 2);
2045 goto retry_timeout;
2046 case -EACCES:
2047 trace_rpcb_prog_unavail_err(task);
2048 /* fail immediately if this is an RPC ping */
2049 if (task->tk_msg.rpc_proc->p_proc == 0) {
2050 status = -EOPNOTSUPP;
2051 break;
2052 }
2053 if (task->tk_rebind_retry == 0)
2054 break;
2055 task->tk_rebind_retry--;
2056 rpc_delay(task, 3*HZ);
2057 goto retry_timeout;
2058 case -ENOBUFS:
2059 rpc_delay(task, HZ >> 2);
2060 goto retry_timeout;
2061 case -EAGAIN:
2062 goto retry_timeout;
2063 case -ETIMEDOUT:
2064 trace_rpcb_timeout_err(task);
2065 goto retry_timeout;
2066 case -EPFNOSUPPORT:
2067 /* server doesn't support any rpcbind version we know of */
2068 trace_rpcb_bind_version_err(task);
2069 break;
2070 case -EPROTONOSUPPORT:
2071 trace_rpcb_bind_version_err(task);
2072 goto retry_timeout;
2073 case -ECONNREFUSED: /* connection problems */
2074 case -ECONNRESET:
2075 case -ECONNABORTED:
2076 case -ENOTCONN:
2077 case -EHOSTDOWN:
2078 case -ENETDOWN:
2079 case -EHOSTUNREACH:
2080 case -ENETUNREACH:
2081 case -EPIPE:
2082 trace_rpcb_unreachable_err(task);
2083 if (!RPC_IS_SOFTCONN(task)) {
2084 rpc_delay(task, 5*HZ);
2085 goto retry_timeout;
2086 }
2087 status = task->tk_status;
2088 break;
2089 default:
2090 trace_rpcb_unrecognized_err(task);
2091 }
2092
2093 rpc_call_rpcerror(task, status);
2094 return;
2095out_next:
2096 task->tk_action = call_connect;
2097 return;
2098retry_timeout:
2099 task->tk_status = 0;
2100 task->tk_action = call_bind;
2101 rpc_check_timeout(task);
2102}
2103
2104/*
2105 * 4b. Connect to the RPC server
2106 */
2107static void
2108call_connect(struct rpc_task *task)
2109{
2110 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2111
2112 if (rpc_task_transmitted(task)) {
2113 rpc_task_handle_transmitted(task);
2114 return;
2115 }
2116
2117 if (xprt_connected(xprt)) {
2118 task->tk_action = call_transmit;
2119 return;
2120 }
2121
2122 task->tk_action = call_connect_status;
2123 if (task->tk_status < 0)
2124 return;
2125 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2126 rpc_call_rpcerror(task, -ENOTCONN);
2127 return;
2128 }
2129 if (!xprt_prepare_transmit(task))
2130 return;
2131 xprt_connect(task);
2132}
2133
2134/*
2135 * 4c. Sort out connect result
2136 */
2137static void
2138call_connect_status(struct rpc_task *task)
2139{
2140 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2141 struct rpc_clnt *clnt = task->tk_client;
2142 int status = task->tk_status;
2143
2144 if (rpc_task_transmitted(task)) {
2145 rpc_task_handle_transmitted(task);
2146 return;
2147 }
2148
2149 trace_rpc_connect_status(task);
2150
2151 if (task->tk_status == 0) {
2152 clnt->cl_stats->netreconn++;
2153 goto out_next;
2154 }
2155 if (xprt_connected(xprt)) {
2156 task->tk_status = 0;
2157 goto out_next;
2158 }
2159
2160 task->tk_status = 0;
2161 switch (status) {
2162 case -ECONNREFUSED:
2163 /* A positive refusal suggests a rebind is needed. */
2164 if (RPC_IS_SOFTCONN(task))
2165 break;
2166 if (clnt->cl_autobind) {
2167 rpc_force_rebind(clnt);
2168 goto out_retry;
2169 }
2170 fallthrough;
2171 case -ECONNRESET:
2172 case -ECONNABORTED:
2173 case -ENETDOWN:
2174 case -ENETUNREACH:
2175 case -EHOSTUNREACH:
2176 case -EPIPE:
2177 case -EPROTO:
2178 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2179 task->tk_rqstp->rq_connect_cookie);
2180 if (RPC_IS_SOFTCONN(task))
2181 break;
2182 /* retry with existing socket, after a delay */
2183 rpc_delay(task, 3*HZ);
2184 fallthrough;
2185 case -EADDRINUSE:
2186 case -ENOTCONN:
2187 case -EAGAIN:
2188 case -ETIMEDOUT:
2189 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2190 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2191 test_bit(XPRT_REMOVE, &xprt->state)) {
2192 struct rpc_xprt *saved = task->tk_xprt;
2193 struct rpc_xprt_switch *xps;
2194
2195 rcu_read_lock();
2196 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2197 rcu_read_unlock();
2198 if (xps->xps_nxprts > 1) {
2199 long value;
2200
2201 xprt_release(task);
2202 value = atomic_long_dec_return(&xprt->queuelen);
2203 if (value == 0)
2204 rpc_xprt_switch_remove_xprt(xps, saved,
2205 true);
2206 xprt_put(saved);
2207 task->tk_xprt = NULL;
2208 task->tk_action = call_start;
2209 }
2210 xprt_switch_put(xps);
2211 if (!task->tk_xprt)
2212 return;
2213 }
2214 goto out_retry;
2215 case -ENOBUFS:
2216 rpc_delay(task, HZ >> 2);
2217 goto out_retry;
2218 }
2219 rpc_call_rpcerror(task, status);
2220 return;
2221out_next:
2222 task->tk_action = call_transmit;
2223 return;
2224out_retry:
2225 /* Check for timeouts before looping back to call_bind */
2226 task->tk_action = call_bind;
2227 rpc_check_timeout(task);
2228}
2229
2230/*
2231 * 5. Transmit the RPC request, and wait for reply
2232 */
2233static void
2234call_transmit(struct rpc_task *task)
2235{
2236 if (rpc_task_transmitted(task)) {
2237 rpc_task_handle_transmitted(task);
2238 return;
2239 }
2240
2241 task->tk_action = call_transmit_status;
2242 if (!xprt_prepare_transmit(task))
2243 return;
2244 task->tk_status = 0;
2245 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2246 if (!xprt_connected(task->tk_xprt)) {
2247 task->tk_status = -ENOTCONN;
2248 return;
2249 }
2250 xprt_transmit(task);
2251 }
2252 xprt_end_transmit(task);
2253}
2254
2255/*
2256 * 5a. Handle cleanup after a transmission
2257 */
2258static void
2259call_transmit_status(struct rpc_task *task)
2260{
2261 task->tk_action = call_status;
2262
2263 /*
2264 * Common case: success. Force the compiler to put this
2265 * test first.
2266 */
2267 if (rpc_task_transmitted(task)) {
2268 task->tk_status = 0;
2269 xprt_request_wait_receive(task);
2270 return;
2271 }
2272
2273 switch (task->tk_status) {
2274 default:
2275 break;
2276 case -EBADMSG:
2277 task->tk_status = 0;
2278 task->tk_action = call_encode;
2279 break;
2280 /*
2281 * Special cases: if we've been waiting on the
2282 * socket's write_space() callback, or if the
2283 * socket just returned a connection error,
2284 * then hold onto the transport lock.
2285 */
2286 case -ENOMEM:
2287 case -ENOBUFS:
2288 rpc_delay(task, HZ>>2);
2289 fallthrough;
2290 case -EBADSLT:
2291 case -EAGAIN:
2292 task->tk_action = call_transmit;
2293 task->tk_status = 0;
2294 break;
2295 case -ECONNREFUSED:
2296 case -EHOSTDOWN:
2297 case -ENETDOWN:
2298 case -EHOSTUNREACH:
2299 case -ENETUNREACH:
2300 case -EPERM:
2301 if (RPC_IS_SOFTCONN(task)) {
2302 if (!task->tk_msg.rpc_proc->p_proc)
2303 trace_xprt_ping(task->tk_xprt,
2304 task->tk_status);
2305 rpc_call_rpcerror(task, task->tk_status);
2306 return;
2307 }
2308 fallthrough;
2309 case -ECONNRESET:
2310 case -ECONNABORTED:
2311 case -EADDRINUSE:
2312 case -ENOTCONN:
2313 case -EPIPE:
2314 task->tk_action = call_bind;
2315 task->tk_status = 0;
2316 break;
2317 }
2318 rpc_check_timeout(task);
2319}
2320
2321#if defined(CONFIG_SUNRPC_BACKCHANNEL)
2322static void call_bc_transmit(struct rpc_task *task);
2323static void call_bc_transmit_status(struct rpc_task *task);
2324
2325static void
2326call_bc_encode(struct rpc_task *task)
2327{
2328 xprt_request_enqueue_transmit(task);
2329 task->tk_action = call_bc_transmit;
2330}
2331
2332/*
2333 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2334 * addition, disconnect on connectivity errors.
2335 */
2336static void
2337call_bc_transmit(struct rpc_task *task)
2338{
2339 task->tk_action = call_bc_transmit_status;
2340 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2341 if (!xprt_prepare_transmit(task))
2342 return;
2343 task->tk_status = 0;
2344 xprt_transmit(task);
2345 }
2346 xprt_end_transmit(task);
2347}
2348
2349static void
2350call_bc_transmit_status(struct rpc_task *task)
2351{
2352 struct rpc_rqst *req = task->tk_rqstp;
2353
2354 if (rpc_task_transmitted(task))
2355 task->tk_status = 0;
2356
2357 switch (task->tk_status) {
2358 case 0:
2359 /* Success */
2360 case -ENETDOWN:
2361 case -EHOSTDOWN:
2362 case -EHOSTUNREACH:
2363 case -ENETUNREACH:
2364 case -ECONNRESET:
2365 case -ECONNREFUSED:
2366 case -EADDRINUSE:
2367 case -ENOTCONN:
2368 case -EPIPE:
2369 break;
2370 case -ENOMEM:
2371 case -ENOBUFS:
2372 rpc_delay(task, HZ>>2);
2373 fallthrough;
2374 case -EBADSLT:
2375 case -EAGAIN:
2376 task->tk_status = 0;
2377 task->tk_action = call_bc_transmit;
2378 return;
2379 case -ETIMEDOUT:
2380 /*
2381 * Problem reaching the server. Disconnect and let the
2382 * forechannel reestablish the connection. The server will
2383 * have to retransmit the backchannel request and we'll
2384 * reprocess it. Since these ops are idempotent, there's no
2385 * need to cache our reply at this time.
2386 */
2387 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2388 "error: %d\n", task->tk_status);
2389 xprt_conditional_disconnect(req->rq_xprt,
2390 req->rq_connect_cookie);
2391 break;
2392 default:
2393 /*
2394 * We were unable to reply and will have to drop the
2395 * request. The server should reconnect and retransmit.
2396 */
2397 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2398 "error: %d\n", task->tk_status);
2399 break;
2400 }
2401 task->tk_action = rpc_exit_task;
2402}
2403#endif /* CONFIG_SUNRPC_BACKCHANNEL */
2404
2405/*
2406 * 6. Sort out the RPC call status
2407 */
2408static void
2409call_status(struct rpc_task *task)
2410{
2411 struct rpc_clnt *clnt = task->tk_client;
2412 int status;
2413
2414 if (!task->tk_msg.rpc_proc->p_proc)
2415 trace_xprt_ping(task->tk_xprt, task->tk_status);
2416
2417 status = task->tk_status;
2418 if (status >= 0) {
2419 task->tk_action = call_decode;
2420 return;
2421 }
2422
2423 trace_rpc_call_status(task);
2424 task->tk_status = 0;
2425 switch(status) {
2426 case -EHOSTDOWN:
2427 case -ENETDOWN:
2428 case -EHOSTUNREACH:
2429 case -ENETUNREACH:
2430 case -EPERM:
2431 if (RPC_IS_SOFTCONN(task))
2432 goto out_exit;
2433 /*
2434 * Delay any retries for 3 seconds, then handle as if it
2435 * were a timeout.
2436 */
2437 rpc_delay(task, 3*HZ);
2438 fallthrough;
2439 case -ETIMEDOUT:
2440 break;
2441 case -ECONNREFUSED:
2442 case -ECONNRESET:
2443 case -ECONNABORTED:
2444 case -ENOTCONN:
2445 rpc_force_rebind(clnt);
2446 break;
2447 case -EADDRINUSE:
2448 rpc_delay(task, 3*HZ);
2449 fallthrough;
2450 case -EPIPE:
2451 case -EAGAIN:
2452 break;
2453 case -ENFILE:
2454 case -ENOBUFS:
2455 case -ENOMEM:
2456 rpc_delay(task, HZ>>2);
2457 break;
2458 case -EIO:
2459 /* shutdown or soft timeout */
2460 goto out_exit;
2461 default:
2462 if (clnt->cl_chatty)
2463 printk("%s: RPC call returned error %d\n",
2464 clnt->cl_program->name, -status);
2465 goto out_exit;
2466 }
2467 task->tk_action = call_encode;
2468 if (status != -ECONNRESET && status != -ECONNABORTED)
2469 rpc_check_timeout(task);
2470 return;
2471out_exit:
2472 rpc_call_rpcerror(task, status);
2473}
2474
2475static bool
2476rpc_check_connected(const struct rpc_rqst *req)
2477{
2478 /* No allocated request or transport? return true */
2479 if (!req || !req->rq_xprt)
2480 return true;
2481 return xprt_connected(req->rq_xprt);
2482}
2483
2484static void
2485rpc_check_timeout(struct rpc_task *task)
2486{
2487 struct rpc_clnt *clnt = task->tk_client;
2488
2489 if (RPC_SIGNALLED(task))
2490 return;
2491
2492 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2493 return;
2494
2495 trace_rpc_timeout_status(task);
2496 task->tk_timeouts++;
2497
2498 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2499 rpc_call_rpcerror(task, -ETIMEDOUT);
2500 return;
2501 }
2502
2503 if (RPC_IS_SOFT(task)) {
2504 /*
2505 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2506 * been sent, it should time out only if the transport
2507 * connection gets terminally broken.
2508 */
2509 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2510 rpc_check_connected(task->tk_rqstp))
2511 return;
2512
2513 if (clnt->cl_chatty) {
2514 pr_notice_ratelimited(
2515 "%s: server %s not responding, timed out\n",
2516 clnt->cl_program->name,
2517 task->tk_xprt->servername);
2518 }
2519 if (task->tk_flags & RPC_TASK_TIMEOUT)
2520 rpc_call_rpcerror(task, -ETIMEDOUT);
2521 else
2522 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2523 return;
2524 }
2525
2526 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2527 task->tk_flags |= RPC_CALL_MAJORSEEN;
2528 if (clnt->cl_chatty) {
2529 pr_notice_ratelimited(
2530 "%s: server %s not responding, still trying\n",
2531 clnt->cl_program->name,
2532 task->tk_xprt->servername);
2533 }
2534 }
2535 rpc_force_rebind(clnt);
2536 /*
2537 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2538 * event? RFC2203 requires the server to drop all such requests.
2539 */
2540 rpcauth_invalcred(task);
2541}
2542
2543/*
2544 * 7. Decode the RPC reply
2545 */
2546static void
2547call_decode(struct rpc_task *task)
2548{
2549 struct rpc_clnt *clnt = task->tk_client;
2550 struct rpc_rqst *req = task->tk_rqstp;
2551 struct xdr_stream xdr;
2552 int err;
2553
2554 if (!task->tk_msg.rpc_proc->p_decode) {
2555 task->tk_action = rpc_exit_task;
2556 return;
2557 }
2558
2559 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2560 if (clnt->cl_chatty) {
2561 pr_notice_ratelimited("%s: server %s OK\n",
2562 clnt->cl_program->name,
2563 task->tk_xprt->servername);
2564 }
2565 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2566 }
2567
2568 /*
2569 * Did we ever call xprt_complete_rqst()? If not, we should assume
2570 * the message is incomplete.
2571 */
2572 err = -EAGAIN;
2573 if (!req->rq_reply_bytes_recvd)
2574 goto out;
2575
2576 /* Ensure that we see all writes made by xprt_complete_rqst()
2577 * before it changed req->rq_reply_bytes_recvd.
2578 */
2579 smp_rmb();
2580
2581 req->rq_rcv_buf.len = req->rq_private_buf.len;
2582 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2583
2584 /* Check that the softirq receive buffer is valid */
2585 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2586 sizeof(req->rq_rcv_buf)) != 0);
2587
2588 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2589 req->rq_rcv_buf.head[0].iov_base, req);
2590 err = rpc_decode_header(task, &xdr);
2591out:
2592 switch (err) {
2593 case 0:
2594 task->tk_action = rpc_exit_task;
2595 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2596 return;
2597 case -EAGAIN:
2598 task->tk_status = 0;
2599 if (task->tk_client->cl_discrtry)
2600 xprt_conditional_disconnect(req->rq_xprt,
2601 req->rq_connect_cookie);
2602 task->tk_action = call_encode;
2603 rpc_check_timeout(task);
2604 break;
2605 case -EKEYREJECTED:
2606 task->tk_action = call_reserve;
2607 rpc_check_timeout(task);
2608 rpcauth_invalcred(task);
2609 /* Ensure we obtain a new XID if we retry! */
2610 xprt_release(task);
2611 }
2612}
2613
2614static int
2615rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2616{
2617 struct rpc_clnt *clnt = task->tk_client;
2618 struct rpc_rqst *req = task->tk_rqstp;
2619 __be32 *p;
2620 int error;
2621
2622 error = -EMSGSIZE;
2623 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2624 if (!p)
2625 goto out_fail;
2626 *p++ = req->rq_xid;
2627 *p++ = rpc_call;
2628 *p++ = cpu_to_be32(RPC_VERSION);
2629 *p++ = cpu_to_be32(clnt->cl_prog);
2630 *p++ = cpu_to_be32(clnt->cl_vers);
2631 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2632
2633 error = rpcauth_marshcred(task, xdr);
2634 if (error < 0)
2635 goto out_fail;
2636 return 0;
2637out_fail:
2638 trace_rpc_bad_callhdr(task);
2639 rpc_call_rpcerror(task, error);
2640 return error;
2641}
2642
2643static noinline int
2644rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2645{
2646 struct rpc_clnt *clnt = task->tk_client;
2647 int error;
2648 __be32 *p;
2649
2650 /* RFC-1014 says that the representation of XDR data must be a
2651 * multiple of four bytes
2652 * - if it isn't pointer subtraction in the NFS client may give
2653 * undefined results
2654 */
2655 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2656 goto out_unparsable;
2657
2658 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2659 if (!p)
2660 goto out_unparsable;
2661 p++; /* skip XID */
2662 if (*p++ != rpc_reply)
2663 goto out_unparsable;
2664 if (*p++ != rpc_msg_accepted)
2665 goto out_msg_denied;
2666
2667 error = rpcauth_checkverf(task, xdr);
2668 if (error)
2669 goto out_verifier;
2670
2671 p = xdr_inline_decode(xdr, sizeof(*p));
2672 if (!p)
2673 goto out_unparsable;
2674 switch (*p) {
2675 case rpc_success:
2676 return 0;
2677 case rpc_prog_unavail:
2678 trace_rpc__prog_unavail(task);
2679 error = -EPFNOSUPPORT;
2680 goto out_err;
2681 case rpc_prog_mismatch:
2682 trace_rpc__prog_mismatch(task);
2683 error = -EPROTONOSUPPORT;
2684 goto out_err;
2685 case rpc_proc_unavail:
2686 trace_rpc__proc_unavail(task);
2687 error = -EOPNOTSUPP;
2688 goto out_err;
2689 case rpc_garbage_args:
2690 case rpc_system_err:
2691 trace_rpc__garbage_args(task);
2692 error = -EIO;
2693 break;
2694 default:
2695 goto out_unparsable;
2696 }
2697
2698out_garbage:
2699 clnt->cl_stats->rpcgarbage++;
2700 if (task->tk_garb_retry) {
2701 task->tk_garb_retry--;
2702 task->tk_action = call_encode;
2703 return -EAGAIN;
2704 }
2705out_err:
2706 rpc_call_rpcerror(task, error);
2707 return error;
2708
2709out_unparsable:
2710 trace_rpc__unparsable(task);
2711 error = -EIO;
2712 goto out_garbage;
2713
2714out_verifier:
2715 trace_rpc_bad_verifier(task);
2716 goto out_err;
2717
2718out_msg_denied:
2719 error = -EACCES;
2720 p = xdr_inline_decode(xdr, sizeof(*p));
2721 if (!p)
2722 goto out_unparsable;
2723 switch (*p++) {
2724 case rpc_auth_error:
2725 break;
2726 case rpc_mismatch:
2727 trace_rpc__mismatch(task);
2728 error = -EPROTONOSUPPORT;
2729 goto out_err;
2730 default:
2731 goto out_unparsable;
2732 }
2733
2734 p = xdr_inline_decode(xdr, sizeof(*p));
2735 if (!p)
2736 goto out_unparsable;
2737 switch (*p++) {
2738 case rpc_autherr_rejectedcred:
2739 case rpc_autherr_rejectedverf:
2740 case rpcsec_gsserr_credproblem:
2741 case rpcsec_gsserr_ctxproblem:
2742 if (!task->tk_cred_retry)
2743 break;
2744 task->tk_cred_retry--;
2745 trace_rpc__stale_creds(task);
2746 return -EKEYREJECTED;
2747 case rpc_autherr_badcred:
2748 case rpc_autherr_badverf:
2749 /* possibly garbled cred/verf? */
2750 if (!task->tk_garb_retry)
2751 break;
2752 task->tk_garb_retry--;
2753 trace_rpc__bad_creds(task);
2754 task->tk_action = call_encode;
2755 return -EAGAIN;
2756 case rpc_autherr_tooweak:
2757 trace_rpc__auth_tooweak(task);
2758 pr_warn("RPC: server %s requires stronger authentication.\n",
2759 task->tk_xprt->servername);
2760 break;
2761 default:
2762 goto out_unparsable;
2763 }
2764 goto out_err;
2765}
2766
2767static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2768 const void *obj)
2769{
2770}
2771
2772static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2773 void *obj)
2774{
2775 return 0;
2776}
2777
2778static const struct rpc_procinfo rpcproc_null = {
2779 .p_encode = rpcproc_encode_null,
2780 .p_decode = rpcproc_decode_null,
2781};
2782
2783static const struct rpc_procinfo rpcproc_null_noreply = {
2784 .p_encode = rpcproc_encode_null,
2785};
2786
2787static void
2788rpc_null_call_prepare(struct rpc_task *task, void *data)
2789{
2790 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2791 rpc_call_start(task);
2792}
2793
2794static const struct rpc_call_ops rpc_null_ops = {
2795 .rpc_call_prepare = rpc_null_call_prepare,
2796 .rpc_call_done = rpc_default_callback,
2797};
2798
2799static
2800struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2801 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2802 const struct rpc_call_ops *ops, void *data)
2803{
2804 struct rpc_message msg = {
2805 .rpc_proc = &rpcproc_null,
2806 };
2807 struct rpc_task_setup task_setup_data = {
2808 .rpc_client = clnt,
2809 .rpc_xprt = xprt,
2810 .rpc_message = &msg,
2811 .rpc_op_cred = cred,
2812 .callback_ops = ops ?: &rpc_null_ops,
2813 .callback_data = data,
2814 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2815 RPC_TASK_NULLCREDS,
2816 };
2817
2818 return rpc_run_task(&task_setup_data);
2819}
2820
2821struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2822{
2823 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2824}
2825EXPORT_SYMBOL_GPL(rpc_call_null);
2826
2827static int rpc_ping(struct rpc_clnt *clnt)
2828{
2829 struct rpc_task *task;
2830 int status;
2831
2832 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2833 if (IS_ERR(task))
2834 return PTR_ERR(task);
2835 status = task->tk_status;
2836 rpc_put_task(task);
2837 return status;
2838}
2839
2840static int rpc_ping_noreply(struct rpc_clnt *clnt)
2841{
2842 struct rpc_message msg = {
2843 .rpc_proc = &rpcproc_null_noreply,
2844 };
2845 struct rpc_task_setup task_setup_data = {
2846 .rpc_client = clnt,
2847 .rpc_message = &msg,
2848 .callback_ops = &rpc_null_ops,
2849 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2850 };
2851 struct rpc_task *task;
2852 int status;
2853
2854 task = rpc_run_task(&task_setup_data);
2855 if (IS_ERR(task))
2856 return PTR_ERR(task);
2857 status = task->tk_status;
2858 rpc_put_task(task);
2859 return status;
2860}
2861
2862struct rpc_cb_add_xprt_calldata {
2863 struct rpc_xprt_switch *xps;
2864 struct rpc_xprt *xprt;
2865};
2866
2867static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2868{
2869 struct rpc_cb_add_xprt_calldata *data = calldata;
2870
2871 if (task->tk_status == 0)
2872 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2873}
2874
2875static void rpc_cb_add_xprt_release(void *calldata)
2876{
2877 struct rpc_cb_add_xprt_calldata *data = calldata;
2878
2879 xprt_put(data->xprt);
2880 xprt_switch_put(data->xps);
2881 kfree(data);
2882}
2883
2884static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2885 .rpc_call_prepare = rpc_null_call_prepare,
2886 .rpc_call_done = rpc_cb_add_xprt_done,
2887 .rpc_release = rpc_cb_add_xprt_release,
2888};
2889
2890/**
2891 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2892 * @clnt: pointer to struct rpc_clnt
2893 * @xps: pointer to struct rpc_xprt_switch,
2894 * @xprt: pointer struct rpc_xprt
2895 * @dummy: unused
2896 */
2897int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2898 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2899 void *dummy)
2900{
2901 struct rpc_cb_add_xprt_calldata *data;
2902 struct rpc_task *task;
2903
2904 if (xps->xps_nunique_destaddr_xprts + 1 > clnt->cl_max_connect) {
2905 rcu_read_lock();
2906 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2907 "transport to server: %s\n", clnt->cl_max_connect,
2908 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2909 rcu_read_unlock();
2910 return -EINVAL;
2911 }
2912
2913 data = kmalloc(sizeof(*data), GFP_KERNEL);
2914 if (!data)
2915 return -ENOMEM;
2916 data->xps = xprt_switch_get(xps);
2917 data->xprt = xprt_get(xprt);
2918 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2919 rpc_cb_add_xprt_release(data);
2920 goto success;
2921 }
2922
2923 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2924 &rpc_cb_add_xprt_call_ops, data);
2925 if (IS_ERR(task))
2926 return PTR_ERR(task);
2927
2928 data->xps->xps_nunique_destaddr_xprts++;
2929 rpc_put_task(task);
2930success:
2931 return 1;
2932}
2933EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2934
2935static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2936 struct rpc_xprt *xprt,
2937 struct rpc_add_xprt_test *data)
2938{
2939 struct rpc_task *task;
2940 int status = -EADDRINUSE;
2941
2942 /* Test the connection */
2943 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2944 if (IS_ERR(task))
2945 return PTR_ERR(task);
2946
2947 status = task->tk_status;
2948 rpc_put_task(task);
2949
2950 if (status < 0)
2951 return status;
2952
2953 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2954 data->add_xprt_test(clnt, xprt, data->data);
2955
2956 return 0;
2957}
2958
2959/**
2960 * rpc_clnt_setup_test_and_add_xprt()
2961 *
2962 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2963 * 1) caller of the test function must dereference the rpc_xprt_switch
2964 * and the rpc_xprt.
2965 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2966 * the rpc_call_done routine.
2967 *
2968 * Upon success (return of 1), the test function adds the new
2969 * transport to the rpc_clnt xprt switch
2970 *
2971 * @clnt: struct rpc_clnt to get the new transport
2972 * @xps: the rpc_xprt_switch to hold the new transport
2973 * @xprt: the rpc_xprt to test
2974 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2975 * and test function call data
2976 */
2977int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2978 struct rpc_xprt_switch *xps,
2979 struct rpc_xprt *xprt,
2980 void *data)
2981{
2982 int status = -EADDRINUSE;
2983
2984 xprt = xprt_get(xprt);
2985 xprt_switch_get(xps);
2986
2987 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2988 goto out_err;
2989
2990 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
2991 if (status < 0)
2992 goto out_err;
2993
2994 status = 1;
2995out_err:
2996 xprt_put(xprt);
2997 xprt_switch_put(xps);
2998 if (status < 0)
2999 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3000 "added\n", status,
3001 xprt->address_strings[RPC_DISPLAY_ADDR]);
3002 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3003 return status;
3004}
3005EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3006
3007/**
3008 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3009 * @clnt: pointer to struct rpc_clnt
3010 * @xprtargs: pointer to struct xprt_create
3011 * @setup: callback to test and/or set up the connection
3012 * @data: pointer to setup function data
3013 *
3014 * Creates a new transport using the parameters set in args and
3015 * adds it to clnt.
3016 * If ping is set, then test that connectivity succeeds before
3017 * adding the new transport.
3018 *
3019 */
3020int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3021 struct xprt_create *xprtargs,
3022 int (*setup)(struct rpc_clnt *,
3023 struct rpc_xprt_switch *,
3024 struct rpc_xprt *,
3025 void *),
3026 void *data)
3027{
3028 struct rpc_xprt_switch *xps;
3029 struct rpc_xprt *xprt;
3030 unsigned long connect_timeout;
3031 unsigned long reconnect_timeout;
3032 unsigned char resvport, reuseport;
3033 int ret = 0, ident;
3034
3035 rcu_read_lock();
3036 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3037 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3038 if (xps == NULL || xprt == NULL) {
3039 rcu_read_unlock();
3040 xprt_switch_put(xps);
3041 return -EAGAIN;
3042 }
3043 resvport = xprt->resvport;
3044 reuseport = xprt->reuseport;
3045 connect_timeout = xprt->connect_timeout;
3046 reconnect_timeout = xprt->max_reconnect_timeout;
3047 ident = xprt->xprt_class->ident;
3048 rcu_read_unlock();
3049
3050 if (!xprtargs->ident)
3051 xprtargs->ident = ident;
3052 xprt = xprt_create_transport(xprtargs);
3053 if (IS_ERR(xprt)) {
3054 ret = PTR_ERR(xprt);
3055 goto out_put_switch;
3056 }
3057 xprt->resvport = resvport;
3058 xprt->reuseport = reuseport;
3059 if (xprt->ops->set_connect_timeout != NULL)
3060 xprt->ops->set_connect_timeout(xprt,
3061 connect_timeout,
3062 reconnect_timeout);
3063
3064 rpc_xprt_switch_set_roundrobin(xps);
3065 if (setup) {
3066 ret = setup(clnt, xps, xprt, data);
3067 if (ret != 0)
3068 goto out_put_xprt;
3069 }
3070 rpc_xprt_switch_add_xprt(xps, xprt);
3071out_put_xprt:
3072 xprt_put(xprt);
3073out_put_switch:
3074 xprt_switch_put(xps);
3075 return ret;
3076}
3077EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3078
3079static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3080 struct rpc_xprt *xprt,
3081 struct rpc_add_xprt_test *data)
3082{
3083 struct rpc_xprt_switch *xps;
3084 struct rpc_xprt *main_xprt;
3085 int status = 0;
3086
3087 xprt_get(xprt);
3088
3089 rcu_read_lock();
3090 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3091 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3092 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3093 (struct sockaddr *)&main_xprt->addr);
3094 rcu_read_unlock();
3095 xprt_put(main_xprt);
3096 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3097 goto out;
3098
3099 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3100out:
3101 xprt_put(xprt);
3102 xprt_switch_put(xps);
3103 return status;
3104}
3105
3106/* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3107 * @clnt rpc_clnt structure
3108 *
3109 * For each offlined transport found in the rpc_clnt structure call
3110 * the function rpc_xprt_probe_trunked() which will determine if this
3111 * transport still belongs to the trunking group.
3112 */
3113void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3114 struct rpc_add_xprt_test *data)
3115{
3116 struct rpc_xprt_iter xpi;
3117 int ret;
3118
3119 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3120 if (ret)
3121 return;
3122 for (;;) {
3123 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3124
3125 if (!xprt)
3126 break;
3127 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3128 xprt_put(xprt);
3129 if (ret < 0)
3130 break;
3131 xprt_iter_rewind(&xpi);
3132 }
3133 xprt_iter_destroy(&xpi);
3134}
3135EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3136
3137static int rpc_xprt_offline(struct rpc_clnt *clnt,
3138 struct rpc_xprt *xprt,
3139 void *data)
3140{
3141 struct rpc_xprt *main_xprt;
3142 struct rpc_xprt_switch *xps;
3143 int err = 0;
3144
3145 xprt_get(xprt);
3146
3147 rcu_read_lock();
3148 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3149 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3150 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3151 (struct sockaddr *)&main_xprt->addr);
3152 rcu_read_unlock();
3153 xprt_put(main_xprt);
3154 if (err)
3155 goto out;
3156
3157 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3158 err = -EINTR;
3159 goto out;
3160 }
3161 xprt_set_offline_locked(xprt, xps);
3162
3163 xprt_release_write(xprt, NULL);
3164out:
3165 xprt_put(xprt);
3166 xprt_switch_put(xps);
3167 return err;
3168}
3169
3170/* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3171 * @clnt rpc_clnt structure
3172 *
3173 * For each active transport found in the rpc_clnt structure call
3174 * the function rpc_xprt_offline() which will identify trunked transports
3175 * and will mark them offline.
3176 */
3177void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3178{
3179 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3180}
3181EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3182
3183struct connect_timeout_data {
3184 unsigned long connect_timeout;
3185 unsigned long reconnect_timeout;
3186};
3187
3188static int
3189rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3190 struct rpc_xprt *xprt,
3191 void *data)
3192{
3193 struct connect_timeout_data *timeo = data;
3194
3195 if (xprt->ops->set_connect_timeout)
3196 xprt->ops->set_connect_timeout(xprt,
3197 timeo->connect_timeout,
3198 timeo->reconnect_timeout);
3199 return 0;
3200}
3201
3202void
3203rpc_set_connect_timeout(struct rpc_clnt *clnt,
3204 unsigned long connect_timeout,
3205 unsigned long reconnect_timeout)
3206{
3207 struct connect_timeout_data timeout = {
3208 .connect_timeout = connect_timeout,
3209 .reconnect_timeout = reconnect_timeout,
3210 };
3211 rpc_clnt_iterate_for_each_xprt(clnt,
3212 rpc_xprt_set_connect_timeout,
3213 &timeout);
3214}
3215EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3216
3217void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
3218{
3219 rcu_read_lock();
3220 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3221 rcu_read_unlock();
3222}
3223EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
3224
3225void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3226{
3227 struct rpc_xprt_switch *xps;
3228
3229 rcu_read_lock();
3230 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3231 rcu_read_unlock();
3232 xprt_set_online_locked(xprt, xps);
3233}
3234
3235void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3236{
3237 if (rpc_clnt_xprt_switch_has_addr(clnt,
3238 (const struct sockaddr *)&xprt->addr)) {
3239 return rpc_clnt_xprt_set_online(clnt, xprt);
3240 }
3241 rcu_read_lock();
3242 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3243 xprt);
3244 rcu_read_unlock();
3245}
3246EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3247
3248void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3249{
3250 struct rpc_xprt_switch *xps;
3251
3252 rcu_read_lock();
3253 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3254 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3255 xprt, 0);
3256 xps->xps_nunique_destaddr_xprts--;
3257 rcu_read_unlock();
3258}
3259EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3260
3261bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3262 const struct sockaddr *sap)
3263{
3264 struct rpc_xprt_switch *xps;
3265 bool ret;
3266
3267 rcu_read_lock();
3268 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3269 ret = rpc_xprt_switch_has_addr(xps, sap);
3270 rcu_read_unlock();
3271 return ret;
3272}
3273EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3274
3275#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3276static void rpc_show_header(void)
3277{
3278 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3279 "-timeout ---ops--\n");
3280}
3281
3282static void rpc_show_task(const struct rpc_clnt *clnt,
3283 const struct rpc_task *task)
3284{
3285 const char *rpc_waitq = "none";
3286
3287 if (RPC_IS_QUEUED(task))
3288 rpc_waitq = rpc_qname(task->tk_waitqueue);
3289
3290 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3291 task->tk_pid, task->tk_flags, task->tk_status,
3292 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3293 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3294 task->tk_action, rpc_waitq);
3295}
3296
3297void rpc_show_tasks(struct net *net)
3298{
3299 struct rpc_clnt *clnt;
3300 struct rpc_task *task;
3301 int header = 0;
3302 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3303
3304 spin_lock(&sn->rpc_client_lock);
3305 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3306 spin_lock(&clnt->cl_lock);
3307 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3308 if (!header) {
3309 rpc_show_header();
3310 header++;
3311 }
3312 rpc_show_task(clnt, task);
3313 }
3314 spin_unlock(&clnt->cl_lock);
3315 }
3316 spin_unlock(&sn->rpc_client_lock);
3317}
3318#endif
3319
3320#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3321static int
3322rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3323 struct rpc_xprt *xprt,
3324 void *dummy)
3325{
3326 return xprt_enable_swap(xprt);
3327}
3328
3329int
3330rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3331{
3332 while (clnt != clnt->cl_parent)
3333 clnt = clnt->cl_parent;
3334 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3335 return rpc_clnt_iterate_for_each_xprt(clnt,
3336 rpc_clnt_swap_activate_callback, NULL);
3337 return 0;
3338}
3339EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3340
3341static int
3342rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3343 struct rpc_xprt *xprt,
3344 void *dummy)
3345{
3346 xprt_disable_swap(xprt);
3347 return 0;
3348}
3349
3350void
3351rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3352{
3353 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3354 rpc_clnt_iterate_for_each_xprt(clnt,
3355 rpc_clnt_swap_deactivate_callback, NULL);
3356}
3357EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3358#endif /* CONFIG_SUNRPC_SWAP */