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WIP FPC-III support
[linux/fpc-iii.git] / net / sunrpc / clnt.c
blob612f0a641f4cf62eb20e1259cb2efe106b9f7823
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/kallsyms.h>
25 #include <linux/mm.h>
26 #include <linux/namei.h>
27 #include <linux/mount.h>
28 #include <linux/slab.h>
29 #include <linux/rcupdate.h>
30 #include <linux/utsname.h>
31 #include <linux/workqueue.h>
32 #include <linux/in.h>
33 #include <linux/in6.h>
34 #include <linux/un.h>
35
36 #include <linux/sunrpc/clnt.h>
37 #include <linux/sunrpc/addr.h>
38 #include <linux/sunrpc/rpc_pipe_fs.h>
39 #include <linux/sunrpc/metrics.h>
40 #include <linux/sunrpc/bc_xprt.h>
41 #include <trace/events/sunrpc.h>
42
43 #include "sunrpc.h"
44 #include "netns.h"
45
46 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
47 # define RPCDBG_FACILITY RPCDBG_CALL
48 #endif
49
50 /*
51 * All RPC clients are linked into this list
52 */
53
54 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
55
56
57 static void call_start(struct rpc_task *task);
58 static void call_reserve(struct rpc_task *task);
59 static void call_reserveresult(struct rpc_task *task);
60 static void call_allocate(struct rpc_task *task);
61 static void call_encode(struct rpc_task *task);
62 static void call_decode(struct rpc_task *task);
63 static void call_bind(struct rpc_task *task);
64 static void call_bind_status(struct rpc_task *task);
65 static void call_transmit(struct rpc_task *task);
66 static void call_status(struct rpc_task *task);
67 static void call_transmit_status(struct rpc_task *task);
68 static void call_refresh(struct rpc_task *task);
69 static void call_refreshresult(struct rpc_task *task);
70 static void call_connect(struct rpc_task *task);
71 static void call_connect_status(struct rpc_task *task);
72
73 static int rpc_encode_header(struct rpc_task *task,
74 struct xdr_stream *xdr);
75 static int rpc_decode_header(struct rpc_task *task,
76 struct xdr_stream *xdr);
77 static int rpc_ping(struct rpc_clnt *clnt);
78 static void rpc_check_timeout(struct rpc_task *task);
79
80 static void rpc_register_client(struct rpc_clnt *clnt)
81 {
82 struct net *net = rpc_net_ns(clnt);
83 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
84
85 spin_lock(&sn->rpc_client_lock);
86 list_add(&clnt->cl_clients, &sn->all_clients);
87 spin_unlock(&sn->rpc_client_lock);
88 }
89
90 static void rpc_unregister_client(struct rpc_clnt *clnt)
91 {
92 struct net *net = rpc_net_ns(clnt);
93 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
94
95 spin_lock(&sn->rpc_client_lock);
96 list_del(&clnt->cl_clients);
97 spin_unlock(&sn->rpc_client_lock);
98 }
99
100 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
101 {
102 rpc_remove_client_dir(clnt);
103 }
104
105 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
106 {
107 struct net *net = rpc_net_ns(clnt);
108 struct super_block *pipefs_sb;
109
110 pipefs_sb = rpc_get_sb_net(net);
111 if (pipefs_sb) {
112 __rpc_clnt_remove_pipedir(clnt);
113 rpc_put_sb_net(net);
114 }
115 }
116
117 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
118 struct rpc_clnt *clnt)
119 {
120 static uint32_t clntid;
121 const char *dir_name = clnt->cl_program->pipe_dir_name;
122 char name[15];
123 struct dentry *dir, *dentry;
124
125 dir = rpc_d_lookup_sb(sb, dir_name);
126 if (dir == NULL) {
127 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
128 return dir;
129 }
130 for (;;) {
131 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
132 name[sizeof(name) - 1] = '\0';
133 dentry = rpc_create_client_dir(dir, name, clnt);
134 if (!IS_ERR(dentry))
135 break;
136 if (dentry == ERR_PTR(-EEXIST))
137 continue;
138 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
139 " %s/%s, error %ld\n",
140 dir_name, name, PTR_ERR(dentry));
141 break;
142 }
143 dput(dir);
144 return dentry;
145 }
146
147 static int
148 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
149 {
150 struct dentry *dentry;
151
152 if (clnt->cl_program->pipe_dir_name != NULL) {
153 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
154 if (IS_ERR(dentry))
155 return PTR_ERR(dentry);
156 }
157 return 0;
158 }
159
160 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
161 {
162 if (clnt->cl_program->pipe_dir_name == NULL)
163 return 1;
164
165 switch (event) {
166 case RPC_PIPEFS_MOUNT:
167 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
168 return 1;
169 if (atomic_read(&clnt->cl_count) == 0)
170 return 1;
171 break;
172 case RPC_PIPEFS_UMOUNT:
173 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
174 return 1;
175 break;
176 }
177 return 0;
178 }
179
180 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
181 struct super_block *sb)
182 {
183 struct dentry *dentry;
184
185 switch (event) {
186 case RPC_PIPEFS_MOUNT:
187 dentry = rpc_setup_pipedir_sb(sb, clnt);
188 if (!dentry)
189 return -ENOENT;
190 if (IS_ERR(dentry))
191 return PTR_ERR(dentry);
192 break;
193 case RPC_PIPEFS_UMOUNT:
194 __rpc_clnt_remove_pipedir(clnt);
195 break;
196 default:
197 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
198 return -ENOTSUPP;
199 }
200 return 0;
201 }
202
203 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
204 struct super_block *sb)
205 {
206 int error = 0;
207
208 for (;; clnt = clnt->cl_parent) {
209 if (!rpc_clnt_skip_event(clnt, event))
210 error = __rpc_clnt_handle_event(clnt, event, sb);
211 if (error || clnt == clnt->cl_parent)
212 break;
213 }
214 return error;
215 }
216
217 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
218 {
219 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
220 struct rpc_clnt *clnt;
221
222 spin_lock(&sn->rpc_client_lock);
223 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
224 if (rpc_clnt_skip_event(clnt, event))
225 continue;
226 spin_unlock(&sn->rpc_client_lock);
227 return clnt;
228 }
229 spin_unlock(&sn->rpc_client_lock);
230 return NULL;
231 }
232
233 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
234 void *ptr)
235 {
236 struct super_block *sb = ptr;
237 struct rpc_clnt *clnt;
238 int error = 0;
239
240 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
241 error = __rpc_pipefs_event(clnt, event, sb);
242 if (error)
243 break;
244 }
245 return error;
246 }
247
248 static struct notifier_block rpc_clients_block = {
249 .notifier_call = rpc_pipefs_event,
250 .priority = SUNRPC_PIPEFS_RPC_PRIO,
251 };
252
253 int rpc_clients_notifier_register(void)
254 {
255 return rpc_pipefs_notifier_register(&rpc_clients_block);
256 }
257
258 void rpc_clients_notifier_unregister(void)
259 {
260 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
261 }
262
263 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
264 struct rpc_xprt *xprt,
265 const struct rpc_timeout *timeout)
266 {
267 struct rpc_xprt *old;
268
269 spin_lock(&clnt->cl_lock);
270 old = rcu_dereference_protected(clnt->cl_xprt,
271 lockdep_is_held(&clnt->cl_lock));
272
273 if (!xprt_bound(xprt))
274 clnt->cl_autobind = 1;
275
276 clnt->cl_timeout = timeout;
277 rcu_assign_pointer(clnt->cl_xprt, xprt);
278 spin_unlock(&clnt->cl_lock);
279
280 return old;
281 }
282
283 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
284 {
285 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
286 nodename, sizeof(clnt->cl_nodename));
287 }
288
289 static int rpc_client_register(struct rpc_clnt *clnt,
290 rpc_authflavor_t pseudoflavor,
291 const char *client_name)
292 {
293 struct rpc_auth_create_args auth_args = {
294 .pseudoflavor = pseudoflavor,
295 .target_name = client_name,
296 };
297 struct rpc_auth *auth;
298 struct net *net = rpc_net_ns(clnt);
299 struct super_block *pipefs_sb;
300 int err;
301
302 rpc_clnt_debugfs_register(clnt);
303
304 pipefs_sb = rpc_get_sb_net(net);
305 if (pipefs_sb) {
306 err = rpc_setup_pipedir(pipefs_sb, clnt);
307 if (err)
308 goto out;
309 }
310
311 rpc_register_client(clnt);
312 if (pipefs_sb)
313 rpc_put_sb_net(net);
314
315 auth = rpcauth_create(&auth_args, clnt);
316 if (IS_ERR(auth)) {
317 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
318 pseudoflavor);
319 err = PTR_ERR(auth);
320 goto err_auth;
321 }
322 return 0;
323 err_auth:
324 pipefs_sb = rpc_get_sb_net(net);
325 rpc_unregister_client(clnt);
326 __rpc_clnt_remove_pipedir(clnt);
327 out:
328 if (pipefs_sb)
329 rpc_put_sb_net(net);
330 rpc_clnt_debugfs_unregister(clnt);
331 return err;
332 }
333
334 static DEFINE_IDA(rpc_clids);
335
336 void rpc_cleanup_clids(void)
337 {
338 ida_destroy(&rpc_clids);
339 }
340
341 static int rpc_alloc_clid(struct rpc_clnt *clnt)
342 {
343 int clid;
344
345 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
346 if (clid < 0)
347 return clid;
348 clnt->cl_clid = clid;
349 return 0;
350 }
351
352 static void rpc_free_clid(struct rpc_clnt *clnt)
353 {
354 ida_simple_remove(&rpc_clids, clnt->cl_clid);
355 }
356
357 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
358 struct rpc_xprt_switch *xps,
359 struct rpc_xprt *xprt,
360 struct rpc_clnt *parent)
361 {
362 const struct rpc_program *program = args->program;
363 const struct rpc_version *version;
364 struct rpc_clnt *clnt = NULL;
365 const struct rpc_timeout *timeout;
366 const char *nodename = args->nodename;
367 int err;
368
369 err = rpciod_up();
370 if (err)
371 goto out_no_rpciod;
372
373 err = -EINVAL;
374 if (args->version >= program->nrvers)
375 goto out_err;
376 version = program->version[args->version];
377 if (version == NULL)
378 goto out_err;
379
380 err = -ENOMEM;
381 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
382 if (!clnt)
383 goto out_err;
384 clnt->cl_parent = parent ? : clnt;
385
386 err = rpc_alloc_clid(clnt);
387 if (err)
388 goto out_no_clid;
389
390 clnt->cl_cred = get_cred(args->cred);
391 clnt->cl_procinfo = version->procs;
392 clnt->cl_maxproc = version->nrprocs;
393 clnt->cl_prog = args->prognumber ? : program->number;
394 clnt->cl_vers = version->number;
395 clnt->cl_stats = program->stats;
396 clnt->cl_metrics = rpc_alloc_iostats(clnt);
397 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
398 err = -ENOMEM;
399 if (clnt->cl_metrics == NULL)
400 goto out_no_stats;
401 clnt->cl_program = program;
402 INIT_LIST_HEAD(&clnt->cl_tasks);
403 spin_lock_init(&clnt->cl_lock);
404
405 timeout = xprt->timeout;
406 if (args->timeout != NULL) {
407 memcpy(&clnt->cl_timeout_default, args->timeout,
408 sizeof(clnt->cl_timeout_default));
409 timeout = &clnt->cl_timeout_default;
410 }
411
412 rpc_clnt_set_transport(clnt, xprt, timeout);
413 xprt_iter_init(&clnt->cl_xpi, xps);
414 xprt_switch_put(xps);
415
416 clnt->cl_rtt = &clnt->cl_rtt_default;
417 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
418
419 atomic_set(&clnt->cl_count, 1);
420
421 if (nodename == NULL)
422 nodename = utsname()->nodename;
423 /* save the nodename */
424 rpc_clnt_set_nodename(clnt, nodename);
425
426 err = rpc_client_register(clnt, args->authflavor, args->client_name);
427 if (err)
428 goto out_no_path;
429 if (parent)
430 atomic_inc(&parent->cl_count);
431
432 trace_rpc_clnt_new(clnt, xprt, program->name, args->servername);
433 return clnt;
434
435 out_no_path:
436 rpc_free_iostats(clnt->cl_metrics);
437 out_no_stats:
438 put_cred(clnt->cl_cred);
439 rpc_free_clid(clnt);
440 out_no_clid:
441 kfree(clnt);
442 out_err:
443 rpciod_down();
444 out_no_rpciod:
445 xprt_switch_put(xps);
446 xprt_put(xprt);
447 trace_rpc_clnt_new_err(program->name, args->servername, err);
448 return ERR_PTR(err);
449 }
450
451 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
452 struct rpc_xprt *xprt)
453 {
454 struct rpc_clnt *clnt = NULL;
455 struct rpc_xprt_switch *xps;
456
457 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
458 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
459 xps = args->bc_xprt->xpt_bc_xps;
460 xprt_switch_get(xps);
461 } else {
462 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
463 if (xps == NULL) {
464 xprt_put(xprt);
465 return ERR_PTR(-ENOMEM);
466 }
467 if (xprt->bc_xprt) {
468 xprt_switch_get(xps);
469 xprt->bc_xprt->xpt_bc_xps = xps;
470 }
471 }
472 clnt = rpc_new_client(args, xps, xprt, NULL);
473 if (IS_ERR(clnt))
474 return clnt;
475
476 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
477 int err = rpc_ping(clnt);
478 if (err != 0) {
479 rpc_shutdown_client(clnt);
480 return ERR_PTR(err);
481 }
482 }
483
484 clnt->cl_softrtry = 1;
485 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
486 clnt->cl_softrtry = 0;
487 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
488 clnt->cl_softerr = 1;
489 }
490
491 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
492 clnt->cl_autobind = 1;
493 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
494 clnt->cl_noretranstimeo = 1;
495 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
496 clnt->cl_discrtry = 1;
497 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
498 clnt->cl_chatty = 1;
499
500 return clnt;
501 }
502
503 /**
504 * rpc_create - create an RPC client and transport with one call
505 * @args: rpc_clnt create argument structure
506 *
507 * Creates and initializes an RPC transport and an RPC client.
508 *
509 * It can ping the server in order to determine if it is up, and to see if
510 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
511 * this behavior so asynchronous tasks can also use rpc_create.
512 */
513 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
514 {
515 struct rpc_xprt *xprt;
516 struct xprt_create xprtargs = {
517 .net = args->net,
518 .ident = args->protocol,
519 .srcaddr = args->saddress,
520 .dstaddr = args->address,
521 .addrlen = args->addrsize,
522 .servername = args->servername,
523 .bc_xprt = args->bc_xprt,
524 };
525 char servername[48];
526 struct rpc_clnt *clnt;
527 int i;
528
529 if (args->bc_xprt) {
530 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
531 xprt = args->bc_xprt->xpt_bc_xprt;
532 if (xprt) {
533 xprt_get(xprt);
534 return rpc_create_xprt(args, xprt);
535 }
536 }
537
538 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
539 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
540 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
541 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
542 /*
543 * If the caller chooses not to specify a hostname, whip
544 * up a string representation of the passed-in address.
545 */
546 if (xprtargs.servername == NULL) {
547 struct sockaddr_un *sun =
548 (struct sockaddr_un *)args->address;
549 struct sockaddr_in *sin =
550 (struct sockaddr_in *)args->address;
551 struct sockaddr_in6 *sin6 =
552 (struct sockaddr_in6 *)args->address;
553
554 servername[0] = '\0';
555 switch (args->address->sa_family) {
556 case AF_LOCAL:
557 snprintf(servername, sizeof(servername), "%s",
558 sun->sun_path);
559 break;
560 case AF_INET:
561 snprintf(servername, sizeof(servername), "%pI4",
562 &sin->sin_addr.s_addr);
563 break;
564 case AF_INET6:
565 snprintf(servername, sizeof(servername), "%pI6",
566 &sin6->sin6_addr);
567 break;
568 default:
569 /* caller wants default server name, but
570 * address family isn't recognized. */
571 return ERR_PTR(-EINVAL);
572 }
573 xprtargs.servername = servername;
574 }
575
576 xprt = xprt_create_transport(&xprtargs);
577 if (IS_ERR(xprt))
578 return (struct rpc_clnt *)xprt;
579
580 /*
581 * By default, kernel RPC client connects from a reserved port.
582 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
583 * but it is always enabled for rpciod, which handles the connect
584 * operation.
585 */
586 xprt->resvport = 1;
587 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
588 xprt->resvport = 0;
589 xprt->reuseport = 0;
590 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
591 xprt->reuseport = 1;
592
593 clnt = rpc_create_xprt(args, xprt);
594 if (IS_ERR(clnt) || args->nconnect <= 1)
595 return clnt;
596
597 for (i = 0; i < args->nconnect - 1; i++) {
598 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
599 break;
600 }
601 return clnt;
602 }
603 EXPORT_SYMBOL_GPL(rpc_create);
604
605 /*
606 * This function clones the RPC client structure. It allows us to share the
607 * same transport while varying parameters such as the authentication
608 * flavour.
609 */
610 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
611 struct rpc_clnt *clnt)
612 {
613 struct rpc_xprt_switch *xps;
614 struct rpc_xprt *xprt;
615 struct rpc_clnt *new;
616 int err;
617
618 err = -ENOMEM;
619 rcu_read_lock();
620 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
621 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
622 rcu_read_unlock();
623 if (xprt == NULL || xps == NULL) {
624 xprt_put(xprt);
625 xprt_switch_put(xps);
626 goto out_err;
627 }
628 args->servername = xprt->servername;
629 args->nodename = clnt->cl_nodename;
630
631 new = rpc_new_client(args, xps, xprt, clnt);
632 if (IS_ERR(new))
633 return new;
634
635 /* Turn off autobind on clones */
636 new->cl_autobind = 0;
637 new->cl_softrtry = clnt->cl_softrtry;
638 new->cl_softerr = clnt->cl_softerr;
639 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
640 new->cl_discrtry = clnt->cl_discrtry;
641 new->cl_chatty = clnt->cl_chatty;
642 new->cl_principal = clnt->cl_principal;
643 return new;
644
645 out_err:
646 trace_rpc_clnt_clone_err(clnt, err);
647 return ERR_PTR(err);
648 }
649
650 /**
651 * rpc_clone_client - Clone an RPC client structure
652 *
653 * @clnt: RPC client whose parameters are copied
654 *
655 * Returns a fresh RPC client or an ERR_PTR.
656 */
657 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
658 {
659 struct rpc_create_args args = {
660 .program = clnt->cl_program,
661 .prognumber = clnt->cl_prog,
662 .version = clnt->cl_vers,
663 .authflavor = clnt->cl_auth->au_flavor,
664 .cred = clnt->cl_cred,
665 };
666 return __rpc_clone_client(&args, clnt);
667 }
668 EXPORT_SYMBOL_GPL(rpc_clone_client);
669
670 /**
671 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
672 *
673 * @clnt: RPC client whose parameters are copied
674 * @flavor: security flavor for new client
675 *
676 * Returns a fresh RPC client or an ERR_PTR.
677 */
678 struct rpc_clnt *
679 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
680 {
681 struct rpc_create_args args = {
682 .program = clnt->cl_program,
683 .prognumber = clnt->cl_prog,
684 .version = clnt->cl_vers,
685 .authflavor = flavor,
686 .cred = clnt->cl_cred,
687 };
688 return __rpc_clone_client(&args, clnt);
689 }
690 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
691
692 /**
693 * rpc_switch_client_transport: switch the RPC transport on the fly
694 * @clnt: pointer to a struct rpc_clnt
695 * @args: pointer to the new transport arguments
696 * @timeout: pointer to the new timeout parameters
697 *
698 * This function allows the caller to switch the RPC transport for the
699 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
700 * server, for instance. It assumes that the caller has ensured that
701 * there are no active RPC tasks by using some form of locking.
702 *
703 * Returns zero if "clnt" is now using the new xprt. Otherwise a
704 * negative errno is returned, and "clnt" continues to use the old
705 * xprt.
706 */
707 int rpc_switch_client_transport(struct rpc_clnt *clnt,
708 struct xprt_create *args,
709 const struct rpc_timeout *timeout)
710 {
711 const struct rpc_timeout *old_timeo;
712 rpc_authflavor_t pseudoflavor;
713 struct rpc_xprt_switch *xps, *oldxps;
714 struct rpc_xprt *xprt, *old;
715 struct rpc_clnt *parent;
716 int err;
717
718 xprt = xprt_create_transport(args);
719 if (IS_ERR(xprt))
720 return PTR_ERR(xprt);
721
722 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
723 if (xps == NULL) {
724 xprt_put(xprt);
725 return -ENOMEM;
726 }
727
728 pseudoflavor = clnt->cl_auth->au_flavor;
729
730 old_timeo = clnt->cl_timeout;
731 old = rpc_clnt_set_transport(clnt, xprt, timeout);
732 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
733
734 rpc_unregister_client(clnt);
735 __rpc_clnt_remove_pipedir(clnt);
736 rpc_clnt_debugfs_unregister(clnt);
737
738 /*
739 * A new transport was created. "clnt" therefore
740 * becomes the root of a new cl_parent tree. clnt's
741 * children, if it has any, still point to the old xprt.
742 */
743 parent = clnt->cl_parent;
744 clnt->cl_parent = clnt;
745
746 /*
747 * The old rpc_auth cache cannot be re-used. GSS
748 * contexts in particular are between a single
749 * client and server.
750 */
751 err = rpc_client_register(clnt, pseudoflavor, NULL);
752 if (err)
753 goto out_revert;
754
755 synchronize_rcu();
756 if (parent != clnt)
757 rpc_release_client(parent);
758 xprt_switch_put(oldxps);
759 xprt_put(old);
760 trace_rpc_clnt_replace_xprt(clnt);
761 return 0;
762
763 out_revert:
764 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
765 rpc_clnt_set_transport(clnt, old, old_timeo);
766 clnt->cl_parent = parent;
767 rpc_client_register(clnt, pseudoflavor, NULL);
768 xprt_switch_put(xps);
769 xprt_put(xprt);
770 trace_rpc_clnt_replace_xprt_err(clnt);
771 return err;
772 }
773 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
774
775 static
776 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
777 {
778 struct rpc_xprt_switch *xps;
779
780 rcu_read_lock();
781 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
782 rcu_read_unlock();
783 if (xps == NULL)
784 return -EAGAIN;
785 xprt_iter_init_listall(xpi, xps);
786 xprt_switch_put(xps);
787 return 0;
788 }
789
790 /**
791 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
792 * @clnt: pointer to client
793 * @fn: function to apply
794 * @data: void pointer to function data
795 *
796 * Iterates through the list of RPC transports currently attached to the
797 * client and applies the function fn(clnt, xprt, data).
798 *
799 * On error, the iteration stops, and the function returns the error value.
800 */
801 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
802 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
803 void *data)
804 {
805 struct rpc_xprt_iter xpi;
806 int ret;
807
808 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
809 if (ret)
810 return ret;
811 for (;;) {
812 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
813
814 if (!xprt)
815 break;
816 ret = fn(clnt, xprt, data);
817 xprt_put(xprt);
818 if (ret < 0)
819 break;
820 }
821 xprt_iter_destroy(&xpi);
822 return ret;
823 }
824 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
825
826 /*
827 * Kill all tasks for the given client.
828 * XXX: kill their descendants as well?
829 */
830 void rpc_killall_tasks(struct rpc_clnt *clnt)
831 {
832 struct rpc_task *rovr;
833
834
835 if (list_empty(&clnt->cl_tasks))
836 return;
837
838 /*
839 * Spin lock all_tasks to prevent changes...
840 */
841 trace_rpc_clnt_killall(clnt);
842 spin_lock(&clnt->cl_lock);
843 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
844 rpc_signal_task(rovr);
845 spin_unlock(&clnt->cl_lock);
846 }
847 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
848
849 /*
850 * Properly shut down an RPC client, terminating all outstanding
851 * requests.
852 */
853 void rpc_shutdown_client(struct rpc_clnt *clnt)
854 {
855 might_sleep();
856
857 trace_rpc_clnt_shutdown(clnt);
858
859 while (!list_empty(&clnt->cl_tasks)) {
860 rpc_killall_tasks(clnt);
861 wait_event_timeout(destroy_wait,
862 list_empty(&clnt->cl_tasks), 1*HZ);
863 }
864
865 rpc_release_client(clnt);
866 }
867 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
868
869 /*
870 * Free an RPC client
871 */
872 static void rpc_free_client_work(struct work_struct *work)
873 {
874 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
875
876 trace_rpc_clnt_free(clnt);
877
878 /* These might block on processes that might allocate memory,
879 * so they cannot be called in rpciod, so they are handled separately
880 * here.
881 */
882 rpc_clnt_debugfs_unregister(clnt);
883 rpc_free_clid(clnt);
884 rpc_clnt_remove_pipedir(clnt);
885 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
886
887 kfree(clnt);
888 rpciod_down();
889 }
890 static struct rpc_clnt *
891 rpc_free_client(struct rpc_clnt *clnt)
892 {
893 struct rpc_clnt *parent = NULL;
894
895 trace_rpc_clnt_release(clnt);
896 if (clnt->cl_parent != clnt)
897 parent = clnt->cl_parent;
898 rpc_unregister_client(clnt);
899 rpc_free_iostats(clnt->cl_metrics);
900 clnt->cl_metrics = NULL;
901 xprt_iter_destroy(&clnt->cl_xpi);
902 put_cred(clnt->cl_cred);
903
904 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
905 schedule_work(&clnt->cl_work);
906 return parent;
907 }
908
909 /*
910 * Free an RPC client
911 */
912 static struct rpc_clnt *
913 rpc_free_auth(struct rpc_clnt *clnt)
914 {
915 if (clnt->cl_auth == NULL)
916 return rpc_free_client(clnt);
917
918 /*
919 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
920 * release remaining GSS contexts. This mechanism ensures
921 * that it can do so safely.
922 */
923 atomic_inc(&clnt->cl_count);
924 rpcauth_release(clnt->cl_auth);
925 clnt->cl_auth = NULL;
926 if (atomic_dec_and_test(&clnt->cl_count))
927 return rpc_free_client(clnt);
928 return NULL;
929 }
930
931 /*
932 * Release reference to the RPC client
933 */
934 void
935 rpc_release_client(struct rpc_clnt *clnt)
936 {
937 do {
938 if (list_empty(&clnt->cl_tasks))
939 wake_up(&destroy_wait);
940 if (!atomic_dec_and_test(&clnt->cl_count))
941 break;
942 clnt = rpc_free_auth(clnt);
943 } while (clnt != NULL);
944 }
945 EXPORT_SYMBOL_GPL(rpc_release_client);
946
947 /**
948 * rpc_bind_new_program - bind a new RPC program to an existing client
949 * @old: old rpc_client
950 * @program: rpc program to set
951 * @vers: rpc program version
952 *
953 * Clones the rpc client and sets up a new RPC program. This is mainly
954 * of use for enabling different RPC programs to share the same transport.
955 * The Sun NFSv2/v3 ACL protocol can do this.
956 */
957 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
958 const struct rpc_program *program,
959 u32 vers)
960 {
961 struct rpc_create_args args = {
962 .program = program,
963 .prognumber = program->number,
964 .version = vers,
965 .authflavor = old->cl_auth->au_flavor,
966 .cred = old->cl_cred,
967 };
968 struct rpc_clnt *clnt;
969 int err;
970
971 clnt = __rpc_clone_client(&args, old);
972 if (IS_ERR(clnt))
973 goto out;
974 err = rpc_ping(clnt);
975 if (err != 0) {
976 rpc_shutdown_client(clnt);
977 clnt = ERR_PTR(err);
978 }
979 out:
980 return clnt;
981 }
982 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
983
984 struct rpc_xprt *
985 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
986 {
987 struct rpc_xprt_switch *xps;
988
989 if (!xprt)
990 return NULL;
991 rcu_read_lock();
992 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
993 atomic_long_inc(&xps->xps_queuelen);
994 rcu_read_unlock();
995 atomic_long_inc(&xprt->queuelen);
996
997 return xprt;
998 }
999
1000 static void
1001 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1002 {
1003 struct rpc_xprt_switch *xps;
1004
1005 atomic_long_dec(&xprt->queuelen);
1006 rcu_read_lock();
1007 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1008 atomic_long_dec(&xps->xps_queuelen);
1009 rcu_read_unlock();
1010
1011 xprt_put(xprt);
1012 }
1013
1014 void rpc_task_release_transport(struct rpc_task *task)
1015 {
1016 struct rpc_xprt *xprt = task->tk_xprt;
1017
1018 if (xprt) {
1019 task->tk_xprt = NULL;
1020 if (task->tk_client)
1021 rpc_task_release_xprt(task->tk_client, xprt);
1022 else
1023 xprt_put(xprt);
1024 }
1025 }
1026 EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1027
1028 void rpc_task_release_client(struct rpc_task *task)
1029 {
1030 struct rpc_clnt *clnt = task->tk_client;
1031
1032 rpc_task_release_transport(task);
1033 if (clnt != NULL) {
1034 /* Remove from client task list */
1035 spin_lock(&clnt->cl_lock);
1036 list_del(&task->tk_task);
1037 spin_unlock(&clnt->cl_lock);
1038 task->tk_client = NULL;
1039
1040 rpc_release_client(clnt);
1041 }
1042 }
1043
1044 static struct rpc_xprt *
1045 rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1046 {
1047 struct rpc_xprt *xprt;
1048
1049 rcu_read_lock();
1050 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1051 rcu_read_unlock();
1052 return rpc_task_get_xprt(clnt, xprt);
1053 }
1054
1055 static struct rpc_xprt *
1056 rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1057 {
1058 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1059 }
1060
1061 static
1062 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1063 {
1064 if (task->tk_xprt)
1065 return;
1066 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1067 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1068 else
1069 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1070 }
1071
1072 static
1073 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1074 {
1075
1076 if (clnt != NULL) {
1077 rpc_task_set_transport(task, clnt);
1078 task->tk_client = clnt;
1079 atomic_inc(&clnt->cl_count);
1080 if (clnt->cl_softrtry)
1081 task->tk_flags |= RPC_TASK_SOFT;
1082 if (clnt->cl_softerr)
1083 task->tk_flags |= RPC_TASK_TIMEOUT;
1084 if (clnt->cl_noretranstimeo)
1085 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1086 if (atomic_read(&clnt->cl_swapper))
1087 task->tk_flags |= RPC_TASK_SWAPPER;
1088 /* Add to the client's list of all tasks */
1089 spin_lock(&clnt->cl_lock);
1090 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1091 spin_unlock(&clnt->cl_lock);
1092 }
1093 }
1094
1095 static void
1096 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1097 {
1098 if (msg != NULL) {
1099 task->tk_msg.rpc_proc = msg->rpc_proc;
1100 task->tk_msg.rpc_argp = msg->rpc_argp;
1101 task->tk_msg.rpc_resp = msg->rpc_resp;
1102 task->tk_msg.rpc_cred = msg->rpc_cred;
1103 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1104 get_cred(task->tk_msg.rpc_cred);
1105 }
1106 }
1107
1108 /*
1109 * Default callback for async RPC calls
1110 */
1111 static void
1112 rpc_default_callback(struct rpc_task *task, void *data)
1113 {
1114 }
1115
1116 static const struct rpc_call_ops rpc_default_ops = {
1117 .rpc_call_done = rpc_default_callback,
1118 };
1119
1120 /**
1121 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1122 * @task_setup_data: pointer to task initialisation data
1123 */
1124 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1125 {
1126 struct rpc_task *task;
1127
1128 task = rpc_new_task(task_setup_data);
1129
1130 if (!RPC_IS_ASYNC(task))
1131 task->tk_flags |= RPC_TASK_CRED_NOREF;
1132
1133 rpc_task_set_client(task, task_setup_data->rpc_client);
1134 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1135
1136 if (task->tk_action == NULL)
1137 rpc_call_start(task);
1138
1139 atomic_inc(&task->tk_count);
1140 rpc_execute(task);
1141 return task;
1142 }
1143 EXPORT_SYMBOL_GPL(rpc_run_task);
1144
1145 /**
1146 * rpc_call_sync - Perform a synchronous RPC call
1147 * @clnt: pointer to RPC client
1148 * @msg: RPC call parameters
1149 * @flags: RPC call flags
1150 */
1151 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1152 {
1153 struct rpc_task *task;
1154 struct rpc_task_setup task_setup_data = {
1155 .rpc_client = clnt,
1156 .rpc_message = msg,
1157 .callback_ops = &rpc_default_ops,
1158 .flags = flags,
1159 };
1160 int status;
1161
1162 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1163 if (flags & RPC_TASK_ASYNC) {
1164 rpc_release_calldata(task_setup_data.callback_ops,
1165 task_setup_data.callback_data);
1166 return -EINVAL;
1167 }
1168
1169 task = rpc_run_task(&task_setup_data);
1170 if (IS_ERR(task))
1171 return PTR_ERR(task);
1172 status = task->tk_status;
1173 rpc_put_task(task);
1174 return status;
1175 }
1176 EXPORT_SYMBOL_GPL(rpc_call_sync);
1177
1178 /**
1179 * rpc_call_async - Perform an asynchronous RPC call
1180 * @clnt: pointer to RPC client
1181 * @msg: RPC call parameters
1182 * @flags: RPC call flags
1183 * @tk_ops: RPC call ops
1184 * @data: user call data
1185 */
1186 int
1187 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1188 const struct rpc_call_ops *tk_ops, void *data)
1189 {
1190 struct rpc_task *task;
1191 struct rpc_task_setup task_setup_data = {
1192 .rpc_client = clnt,
1193 .rpc_message = msg,
1194 .callback_ops = tk_ops,
1195 .callback_data = data,
1196 .flags = flags|RPC_TASK_ASYNC,
1197 };
1198
1199 task = rpc_run_task(&task_setup_data);
1200 if (IS_ERR(task))
1201 return PTR_ERR(task);
1202 rpc_put_task(task);
1203 return 0;
1204 }
1205 EXPORT_SYMBOL_GPL(rpc_call_async);
1206
1207 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1208 static void call_bc_encode(struct rpc_task *task);
1209
1210 /**
1211 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1212 * rpc_execute against it
1213 * @req: RPC request
1214 */
1215 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1216 {
1217 struct rpc_task *task;
1218 struct rpc_task_setup task_setup_data = {
1219 .callback_ops = &rpc_default_ops,
1220 .flags = RPC_TASK_SOFTCONN |
1221 RPC_TASK_NO_RETRANS_TIMEOUT,
1222 };
1223
1224 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1225 /*
1226 * Create an rpc_task to send the data
1227 */
1228 task = rpc_new_task(&task_setup_data);
1229 xprt_init_bc_request(req, task);
1230
1231 task->tk_action = call_bc_encode;
1232 atomic_inc(&task->tk_count);
1233 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1234 rpc_execute(task);
1235
1236 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1237 return task;
1238 }
1239 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1240
1241 /**
1242 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1243 * @req: RPC request to prepare
1244 * @pages: vector of struct page pointers
1245 * @base: offset in first page where receive should start, in bytes
1246 * @len: expected size of the upper layer data payload, in bytes
1247 * @hdrsize: expected size of upper layer reply header, in XDR words
1248 *
1249 */
1250 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1251 unsigned int base, unsigned int len,
1252 unsigned int hdrsize)
1253 {
1254 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1255
1256 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1257 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1258 }
1259 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1260
1261 void
1262 rpc_call_start(struct rpc_task *task)
1263 {
1264 task->tk_action = call_start;
1265 }
1266 EXPORT_SYMBOL_GPL(rpc_call_start);
1267
1268 /**
1269 * rpc_peeraddr - extract remote peer address from clnt's xprt
1270 * @clnt: RPC client structure
1271 * @buf: target buffer
1272 * @bufsize: length of target buffer
1273 *
1274 * Returns the number of bytes that are actually in the stored address.
1275 */
1276 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1277 {
1278 size_t bytes;
1279 struct rpc_xprt *xprt;
1280
1281 rcu_read_lock();
1282 xprt = rcu_dereference(clnt->cl_xprt);
1283
1284 bytes = xprt->addrlen;
1285 if (bytes > bufsize)
1286 bytes = bufsize;
1287 memcpy(buf, &xprt->addr, bytes);
1288 rcu_read_unlock();
1289
1290 return bytes;
1291 }
1292 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1293
1294 /**
1295 * rpc_peeraddr2str - return remote peer address in printable format
1296 * @clnt: RPC client structure
1297 * @format: address format
1298 *
1299 * NB: the lifetime of the memory referenced by the returned pointer is
1300 * the same as the rpc_xprt itself. As long as the caller uses this
1301 * pointer, it must hold the RCU read lock.
1302 */
1303 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1304 enum rpc_display_format_t format)
1305 {
1306 struct rpc_xprt *xprt;
1307
1308 xprt = rcu_dereference(clnt->cl_xprt);
1309
1310 if (xprt->address_strings[format] != NULL)
1311 return xprt->address_strings[format];
1312 else
1313 return "unprintable";
1314 }
1315 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1316
1317 static const struct sockaddr_in rpc_inaddr_loopback = {
1318 .sin_family = AF_INET,
1319 .sin_addr.s_addr = htonl(INADDR_ANY),
1320 };
1321
1322 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1323 .sin6_family = AF_INET6,
1324 .sin6_addr = IN6ADDR_ANY_INIT,
1325 };
1326
1327 /*
1328 * Try a getsockname() on a connected datagram socket. Using a
1329 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1330 * This conserves the ephemeral port number space.
1331 *
1332 * Returns zero and fills in "buf" if successful; otherwise, a
1333 * negative errno is returned.
1334 */
1335 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1336 struct sockaddr *buf)
1337 {
1338 struct socket *sock;
1339 int err;
1340
1341 err = __sock_create(net, sap->sa_family,
1342 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1343 if (err < 0) {
1344 dprintk("RPC: can't create UDP socket (%d)\n", err);
1345 goto out;
1346 }
1347
1348 switch (sap->sa_family) {
1349 case AF_INET:
1350 err = kernel_bind(sock,
1351 (struct sockaddr *)&rpc_inaddr_loopback,
1352 sizeof(rpc_inaddr_loopback));
1353 break;
1354 case AF_INET6:
1355 err = kernel_bind(sock,
1356 (struct sockaddr *)&rpc_in6addr_loopback,
1357 sizeof(rpc_in6addr_loopback));
1358 break;
1359 default:
1360 err = -EAFNOSUPPORT;
1361 goto out;
1362 }
1363 if (err < 0) {
1364 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1365 goto out_release;
1366 }
1367
1368 err = kernel_connect(sock, sap, salen, 0);
1369 if (err < 0) {
1370 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1371 goto out_release;
1372 }
1373
1374 err = kernel_getsockname(sock, buf);
1375 if (err < 0) {
1376 dprintk("RPC: getsockname failed (%d)\n", err);
1377 goto out_release;
1378 }
1379
1380 err = 0;
1381 if (buf->sa_family == AF_INET6) {
1382 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1383 sin6->sin6_scope_id = 0;
1384 }
1385 dprintk("RPC: %s succeeded\n", __func__);
1386
1387 out_release:
1388 sock_release(sock);
1389 out:
1390 return err;
1391 }
1392
1393 /*
1394 * Scraping a connected socket failed, so we don't have a useable
1395 * local address. Fallback: generate an address that will prevent
1396 * the server from calling us back.
1397 *
1398 * Returns zero and fills in "buf" if successful; otherwise, a
1399 * negative errno is returned.
1400 */
1401 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1402 {
1403 switch (family) {
1404 case AF_INET:
1405 if (buflen < sizeof(rpc_inaddr_loopback))
1406 return -EINVAL;
1407 memcpy(buf, &rpc_inaddr_loopback,
1408 sizeof(rpc_inaddr_loopback));
1409 break;
1410 case AF_INET6:
1411 if (buflen < sizeof(rpc_in6addr_loopback))
1412 return -EINVAL;
1413 memcpy(buf, &rpc_in6addr_loopback,
1414 sizeof(rpc_in6addr_loopback));
1415 break;
1416 default:
1417 dprintk("RPC: %s: address family not supported\n",
1418 __func__);
1419 return -EAFNOSUPPORT;
1420 }
1421 dprintk("RPC: %s: succeeded\n", __func__);
1422 return 0;
1423 }
1424
1425 /**
1426 * rpc_localaddr - discover local endpoint address for an RPC client
1427 * @clnt: RPC client structure
1428 * @buf: target buffer
1429 * @buflen: size of target buffer, in bytes
1430 *
1431 * Returns zero and fills in "buf" and "buflen" if successful;
1432 * otherwise, a negative errno is returned.
1433 *
1434 * This works even if the underlying transport is not currently connected,
1435 * or if the upper layer never previously provided a source address.
1436 *
1437 * The result of this function call is transient: multiple calls in
1438 * succession may give different results, depending on how local
1439 * networking configuration changes over time.
1440 */
1441 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1442 {
1443 struct sockaddr_storage address;
1444 struct sockaddr *sap = (struct sockaddr *)&address;
1445 struct rpc_xprt *xprt;
1446 struct net *net;
1447 size_t salen;
1448 int err;
1449
1450 rcu_read_lock();
1451 xprt = rcu_dereference(clnt->cl_xprt);
1452 salen = xprt->addrlen;
1453 memcpy(sap, &xprt->addr, salen);
1454 net = get_net(xprt->xprt_net);
1455 rcu_read_unlock();
1456
1457 rpc_set_port(sap, 0);
1458 err = rpc_sockname(net, sap, salen, buf);
1459 put_net(net);
1460 if (err != 0)
1461 /* Couldn't discover local address, return ANYADDR */
1462 return rpc_anyaddr(sap->sa_family, buf, buflen);
1463 return 0;
1464 }
1465 EXPORT_SYMBOL_GPL(rpc_localaddr);
1466
1467 void
1468 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1469 {
1470 struct rpc_xprt *xprt;
1471
1472 rcu_read_lock();
1473 xprt = rcu_dereference(clnt->cl_xprt);
1474 if (xprt->ops->set_buffer_size)
1475 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1476 rcu_read_unlock();
1477 }
1478 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1479
1480 /**
1481 * rpc_net_ns - Get the network namespace for this RPC client
1482 * @clnt: RPC client to query
1483 *
1484 */
1485 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1486 {
1487 struct net *ret;
1488
1489 rcu_read_lock();
1490 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1491 rcu_read_unlock();
1492 return ret;
1493 }
1494 EXPORT_SYMBOL_GPL(rpc_net_ns);
1495
1496 /**
1497 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1498 * @clnt: RPC client to query
1499 *
1500 * For stream transports, this is one RPC record fragment (see RFC
1501 * 1831), as we don't support multi-record requests yet. For datagram
1502 * transports, this is the size of an IP packet minus the IP, UDP, and
1503 * RPC header sizes.
1504 */
1505 size_t rpc_max_payload(struct rpc_clnt *clnt)
1506 {
1507 size_t ret;
1508
1509 rcu_read_lock();
1510 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1511 rcu_read_unlock();
1512 return ret;
1513 }
1514 EXPORT_SYMBOL_GPL(rpc_max_payload);
1515
1516 /**
1517 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1518 * @clnt: RPC client to query
1519 */
1520 size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1521 {
1522 struct rpc_xprt *xprt;
1523 size_t ret;
1524
1525 rcu_read_lock();
1526 xprt = rcu_dereference(clnt->cl_xprt);
1527 ret = xprt->ops->bc_maxpayload(xprt);
1528 rcu_read_unlock();
1529 return ret;
1530 }
1531 EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1532
1533 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1534 {
1535 struct rpc_xprt *xprt;
1536 unsigned int ret;
1537
1538 rcu_read_lock();
1539 xprt = rcu_dereference(clnt->cl_xprt);
1540 ret = xprt->ops->bc_num_slots(xprt);
1541 rcu_read_unlock();
1542 return ret;
1543 }
1544 EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1545
1546 /**
1547 * rpc_force_rebind - force transport to check that remote port is unchanged
1548 * @clnt: client to rebind
1549 *
1550 */
1551 void rpc_force_rebind(struct rpc_clnt *clnt)
1552 {
1553 if (clnt->cl_autobind) {
1554 rcu_read_lock();
1555 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1556 rcu_read_unlock();
1557 }
1558 }
1559 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1560
1561 static int
1562 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1563 {
1564 task->tk_status = 0;
1565 task->tk_rpc_status = 0;
1566 task->tk_action = action;
1567 return 1;
1568 }
1569
1570 /*
1571 * Restart an (async) RPC call. Usually called from within the
1572 * exit handler.
1573 */
1574 int
1575 rpc_restart_call(struct rpc_task *task)
1576 {
1577 return __rpc_restart_call(task, call_start);
1578 }
1579 EXPORT_SYMBOL_GPL(rpc_restart_call);
1580
1581 /*
1582 * Restart an (async) RPC call from the call_prepare state.
1583 * Usually called from within the exit handler.
1584 */
1585 int
1586 rpc_restart_call_prepare(struct rpc_task *task)
1587 {
1588 if (task->tk_ops->rpc_call_prepare != NULL)
1589 return __rpc_restart_call(task, rpc_prepare_task);
1590 return rpc_restart_call(task);
1591 }
1592 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1593
1594 const char
1595 *rpc_proc_name(const struct rpc_task *task)
1596 {
1597 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1598
1599 if (proc) {
1600 if (proc->p_name)
1601 return proc->p_name;
1602 else
1603 return "NULL";
1604 } else
1605 return "no proc";
1606 }
1607
1608 static void
1609 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1610 {
1611 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1612 task->tk_rpc_status = rpc_status;
1613 rpc_exit(task, tk_status);
1614 }
1615
1616 static void
1617 rpc_call_rpcerror(struct rpc_task *task, int status)
1618 {
1619 __rpc_call_rpcerror(task, status, status);
1620 }
1621
1622 /*
1623 * 0. Initial state
1624 *
1625 * Other FSM states can be visited zero or more times, but
1626 * this state is visited exactly once for each RPC.
1627 */
1628 static void
1629 call_start(struct rpc_task *task)
1630 {
1631 struct rpc_clnt *clnt = task->tk_client;
1632 int idx = task->tk_msg.rpc_proc->p_statidx;
1633
1634 trace_rpc_request(task);
1635
1636 /* Increment call count (version might not be valid for ping) */
1637 if (clnt->cl_program->version[clnt->cl_vers])
1638 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1639 clnt->cl_stats->rpccnt++;
1640 task->tk_action = call_reserve;
1641 rpc_task_set_transport(task, clnt);
1642 }
1643
1644 /*
1645 * 1. Reserve an RPC call slot
1646 */
1647 static void
1648 call_reserve(struct rpc_task *task)
1649 {
1650 task->tk_status = 0;
1651 task->tk_action = call_reserveresult;
1652 xprt_reserve(task);
1653 }
1654
1655 static void call_retry_reserve(struct rpc_task *task);
1656
1657 /*
1658 * 1b. Grok the result of xprt_reserve()
1659 */
1660 static void
1661 call_reserveresult(struct rpc_task *task)
1662 {
1663 int status = task->tk_status;
1664
1665 /*
1666 * After a call to xprt_reserve(), we must have either
1667 * a request slot or else an error status.
1668 */
1669 task->tk_status = 0;
1670 if (status >= 0) {
1671 if (task->tk_rqstp) {
1672 task->tk_action = call_refresh;
1673 return;
1674 }
1675
1676 rpc_call_rpcerror(task, -EIO);
1677 return;
1678 }
1679
1680 /*
1681 * Even though there was an error, we may have acquired
1682 * a request slot somehow. Make sure not to leak it.
1683 */
1684 if (task->tk_rqstp)
1685 xprt_release(task);
1686
1687 switch (status) {
1688 case -ENOMEM:
1689 rpc_delay(task, HZ >> 2);
1690 fallthrough;
1691 case -EAGAIN: /* woken up; retry */
1692 task->tk_action = call_retry_reserve;
1693 return;
1694 default:
1695 rpc_call_rpcerror(task, status);
1696 }
1697 }
1698
1699 /*
1700 * 1c. Retry reserving an RPC call slot
1701 */
1702 static void
1703 call_retry_reserve(struct rpc_task *task)
1704 {
1705 task->tk_status = 0;
1706 task->tk_action = call_reserveresult;
1707 xprt_retry_reserve(task);
1708 }
1709
1710 /*
1711 * 2. Bind and/or refresh the credentials
1712 */
1713 static void
1714 call_refresh(struct rpc_task *task)
1715 {
1716 task->tk_action = call_refreshresult;
1717 task->tk_status = 0;
1718 task->tk_client->cl_stats->rpcauthrefresh++;
1719 rpcauth_refreshcred(task);
1720 }
1721
1722 /*
1723 * 2a. Process the results of a credential refresh
1724 */
1725 static void
1726 call_refreshresult(struct rpc_task *task)
1727 {
1728 int status = task->tk_status;
1729
1730 task->tk_status = 0;
1731 task->tk_action = call_refresh;
1732 switch (status) {
1733 case 0:
1734 if (rpcauth_uptodatecred(task)) {
1735 task->tk_action = call_allocate;
1736 return;
1737 }
1738 /* Use rate-limiting and a max number of retries if refresh
1739 * had status 0 but failed to update the cred.
1740 */
1741 fallthrough;
1742 case -ETIMEDOUT:
1743 rpc_delay(task, 3*HZ);
1744 fallthrough;
1745 case -EAGAIN:
1746 status = -EACCES;
1747 fallthrough;
1748 case -EKEYEXPIRED:
1749 if (!task->tk_cred_retry)
1750 break;
1751 task->tk_cred_retry--;
1752 trace_rpc_retry_refresh_status(task);
1753 return;
1754 }
1755 trace_rpc_refresh_status(task);
1756 rpc_call_rpcerror(task, status);
1757 }
1758
1759 /*
1760 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1761 * (Note: buffer memory is freed in xprt_release).
1762 */
1763 static void
1764 call_allocate(struct rpc_task *task)
1765 {
1766 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1767 struct rpc_rqst *req = task->tk_rqstp;
1768 struct rpc_xprt *xprt = req->rq_xprt;
1769 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1770 int status;
1771
1772 task->tk_status = 0;
1773 task->tk_action = call_encode;
1774
1775 if (req->rq_buffer)
1776 return;
1777
1778 if (proc->p_proc != 0) {
1779 BUG_ON(proc->p_arglen == 0);
1780 if (proc->p_decode != NULL)
1781 BUG_ON(proc->p_replen == 0);
1782 }
1783
1784 /*
1785 * Calculate the size (in quads) of the RPC call
1786 * and reply headers, and convert both values
1787 * to byte sizes.
1788 */
1789 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1790 proc->p_arglen;
1791 req->rq_callsize <<= 2;
1792 /*
1793 * Note: the reply buffer must at minimum allocate enough space
1794 * for the 'struct accepted_reply' from RFC5531.
1795 */
1796 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1797 max_t(size_t, proc->p_replen, 2);
1798 req->rq_rcvsize <<= 2;
1799
1800 status = xprt->ops->buf_alloc(task);
1801 trace_rpc_buf_alloc(task, status);
1802 xprt_inject_disconnect(xprt);
1803 if (status == 0)
1804 return;
1805 if (status != -ENOMEM) {
1806 rpc_call_rpcerror(task, status);
1807 return;
1808 }
1809
1810 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1811 task->tk_action = call_allocate;
1812 rpc_delay(task, HZ>>4);
1813 return;
1814 }
1815
1816 rpc_call_rpcerror(task, -ERESTARTSYS);
1817 }
1818
1819 static int
1820 rpc_task_need_encode(struct rpc_task *task)
1821 {
1822 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1823 (!(task->tk_flags & RPC_TASK_SENT) ||
1824 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1825 xprt_request_need_retransmit(task));
1826 }
1827
1828 static void
1829 rpc_xdr_encode(struct rpc_task *task)
1830 {
1831 struct rpc_rqst *req = task->tk_rqstp;
1832 struct xdr_stream xdr;
1833
1834 xdr_buf_init(&req->rq_snd_buf,
1835 req->rq_buffer,
1836 req->rq_callsize);
1837 xdr_buf_init(&req->rq_rcv_buf,
1838 req->rq_rbuffer,
1839 req->rq_rcvsize);
1840
1841 req->rq_reply_bytes_recvd = 0;
1842 req->rq_snd_buf.head[0].iov_len = 0;
1843 xdr_init_encode(&xdr, &req->rq_snd_buf,
1844 req->rq_snd_buf.head[0].iov_base, req);
1845 xdr_free_bvec(&req->rq_snd_buf);
1846 if (rpc_encode_header(task, &xdr))
1847 return;
1848
1849 task->tk_status = rpcauth_wrap_req(task, &xdr);
1850 }
1851
1852 /*
1853 * 3. Encode arguments of an RPC call
1854 */
1855 static void
1856 call_encode(struct rpc_task *task)
1857 {
1858 if (!rpc_task_need_encode(task))
1859 goto out;
1860
1861 /* Dequeue task from the receive queue while we're encoding */
1862 xprt_request_dequeue_xprt(task);
1863 /* Encode here so that rpcsec_gss can use correct sequence number. */
1864 rpc_xdr_encode(task);
1865 /* Did the encode result in an error condition? */
1866 if (task->tk_status != 0) {
1867 /* Was the error nonfatal? */
1868 switch (task->tk_status) {
1869 case -EAGAIN:
1870 case -ENOMEM:
1871 rpc_delay(task, HZ >> 4);
1872 break;
1873 case -EKEYEXPIRED:
1874 if (!task->tk_cred_retry) {
1875 rpc_exit(task, task->tk_status);
1876 } else {
1877 task->tk_action = call_refresh;
1878 task->tk_cred_retry--;
1879 trace_rpc_retry_refresh_status(task);
1880 }
1881 break;
1882 default:
1883 rpc_call_rpcerror(task, task->tk_status);
1884 }
1885 return;
1886 }
1887
1888 /* Add task to reply queue before transmission to avoid races */
1889 if (rpc_reply_expected(task))
1890 xprt_request_enqueue_receive(task);
1891 xprt_request_enqueue_transmit(task);
1892 out:
1893 task->tk_action = call_transmit;
1894 /* Check that the connection is OK */
1895 if (!xprt_bound(task->tk_xprt))
1896 task->tk_action = call_bind;
1897 else if (!xprt_connected(task->tk_xprt))
1898 task->tk_action = call_connect;
1899 }
1900
1901 /*
1902 * Helpers to check if the task was already transmitted, and
1903 * to take action when that is the case.
1904 */
1905 static bool
1906 rpc_task_transmitted(struct rpc_task *task)
1907 {
1908 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1909 }
1910
1911 static void
1912 rpc_task_handle_transmitted(struct rpc_task *task)
1913 {
1914 xprt_end_transmit(task);
1915 task->tk_action = call_transmit_status;
1916 }
1917
1918 /*
1919 * 4. Get the server port number if not yet set
1920 */
1921 static void
1922 call_bind(struct rpc_task *task)
1923 {
1924 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1925
1926 if (rpc_task_transmitted(task)) {
1927 rpc_task_handle_transmitted(task);
1928 return;
1929 }
1930
1931 if (xprt_bound(xprt)) {
1932 task->tk_action = call_connect;
1933 return;
1934 }
1935
1936 task->tk_action = call_bind_status;
1937 if (!xprt_prepare_transmit(task))
1938 return;
1939
1940 xprt->ops->rpcbind(task);
1941 }
1942
1943 /*
1944 * 4a. Sort out bind result
1945 */
1946 static void
1947 call_bind_status(struct rpc_task *task)
1948 {
1949 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1950 int status = -EIO;
1951
1952 if (rpc_task_transmitted(task)) {
1953 rpc_task_handle_transmitted(task);
1954 return;
1955 }
1956
1957 if (task->tk_status >= 0)
1958 goto out_next;
1959 if (xprt_bound(xprt)) {
1960 task->tk_status = 0;
1961 goto out_next;
1962 }
1963
1964 switch (task->tk_status) {
1965 case -ENOMEM:
1966 rpc_delay(task, HZ >> 2);
1967 goto retry_timeout;
1968 case -EACCES:
1969 trace_rpcb_prog_unavail_err(task);
1970 /* fail immediately if this is an RPC ping */
1971 if (task->tk_msg.rpc_proc->p_proc == 0) {
1972 status = -EOPNOTSUPP;
1973 break;
1974 }
1975 if (task->tk_rebind_retry == 0)
1976 break;
1977 task->tk_rebind_retry--;
1978 rpc_delay(task, 3*HZ);
1979 goto retry_timeout;
1980 case -ENOBUFS:
1981 rpc_delay(task, HZ >> 2);
1982 goto retry_timeout;
1983 case -EAGAIN:
1984 goto retry_timeout;
1985 case -ETIMEDOUT:
1986 trace_rpcb_timeout_err(task);
1987 goto retry_timeout;
1988 case -EPFNOSUPPORT:
1989 /* server doesn't support any rpcbind version we know of */
1990 trace_rpcb_bind_version_err(task);
1991 break;
1992 case -EPROTONOSUPPORT:
1993 trace_rpcb_bind_version_err(task);
1994 goto retry_timeout;
1995 case -ECONNREFUSED: /* connection problems */
1996 case -ECONNRESET:
1997 case -ECONNABORTED:
1998 case -ENOTCONN:
1999 case -EHOSTDOWN:
2000 case -ENETDOWN:
2001 case -EHOSTUNREACH:
2002 case -ENETUNREACH:
2003 case -EPIPE:
2004 trace_rpcb_unreachable_err(task);
2005 if (!RPC_IS_SOFTCONN(task)) {
2006 rpc_delay(task, 5*HZ);
2007 goto retry_timeout;
2008 }
2009 status = task->tk_status;
2010 break;
2011 default:
2012 trace_rpcb_unrecognized_err(task);
2013 }
2014
2015 rpc_call_rpcerror(task, status);
2016 return;
2017 out_next:
2018 task->tk_action = call_connect;
2019 return;
2020 retry_timeout:
2021 task->tk_status = 0;
2022 task->tk_action = call_bind;
2023 rpc_check_timeout(task);
2024 }
2025
2026 /*
2027 * 4b. Connect to the RPC server
2028 */
2029 static void
2030 call_connect(struct rpc_task *task)
2031 {
2032 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2033
2034 if (rpc_task_transmitted(task)) {
2035 rpc_task_handle_transmitted(task);
2036 return;
2037 }
2038
2039 if (xprt_connected(xprt)) {
2040 task->tk_action = call_transmit;
2041 return;
2042 }
2043
2044 task->tk_action = call_connect_status;
2045 if (task->tk_status < 0)
2046 return;
2047 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2048 rpc_call_rpcerror(task, -ENOTCONN);
2049 return;
2050 }
2051 if (!xprt_prepare_transmit(task))
2052 return;
2053 xprt_connect(task);
2054 }
2055
2056 /*
2057 * 4c. Sort out connect result
2058 */
2059 static void
2060 call_connect_status(struct rpc_task *task)
2061 {
2062 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2063 struct rpc_clnt *clnt = task->tk_client;
2064 int status = task->tk_status;
2065
2066 if (rpc_task_transmitted(task)) {
2067 rpc_task_handle_transmitted(task);
2068 return;
2069 }
2070
2071 trace_rpc_connect_status(task);
2072
2073 if (task->tk_status == 0) {
2074 clnt->cl_stats->netreconn++;
2075 goto out_next;
2076 }
2077 if (xprt_connected(xprt)) {
2078 task->tk_status = 0;
2079 goto out_next;
2080 }
2081
2082 task->tk_status = 0;
2083 switch (status) {
2084 case -ECONNREFUSED:
2085 /* A positive refusal suggests a rebind is needed. */
2086 if (RPC_IS_SOFTCONN(task))
2087 break;
2088 if (clnt->cl_autobind) {
2089 rpc_force_rebind(clnt);
2090 goto out_retry;
2091 }
2092 fallthrough;
2093 case -ECONNRESET:
2094 case -ECONNABORTED:
2095 case -ENETDOWN:
2096 case -ENETUNREACH:
2097 case -EHOSTUNREACH:
2098 case -EPIPE:
2099 case -EPROTO:
2100 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2101 task->tk_rqstp->rq_connect_cookie);
2102 if (RPC_IS_SOFTCONN(task))
2103 break;
2104 /* retry with existing socket, after a delay */
2105 rpc_delay(task, 3*HZ);
2106 fallthrough;
2107 case -EADDRINUSE:
2108 case -ENOTCONN:
2109 case -EAGAIN:
2110 case -ETIMEDOUT:
2111 goto out_retry;
2112 case -ENOBUFS:
2113 rpc_delay(task, HZ >> 2);
2114 goto out_retry;
2115 }
2116 rpc_call_rpcerror(task, status);
2117 return;
2118 out_next:
2119 task->tk_action = call_transmit;
2120 return;
2121 out_retry:
2122 /* Check for timeouts before looping back to call_bind */
2123 task->tk_action = call_bind;
2124 rpc_check_timeout(task);
2125 }
2126
2127 /*
2128 * 5. Transmit the RPC request, and wait for reply
2129 */
2130 static void
2131 call_transmit(struct rpc_task *task)
2132 {
2133 if (rpc_task_transmitted(task)) {
2134 rpc_task_handle_transmitted(task);
2135 return;
2136 }
2137
2138 task->tk_action = call_transmit_status;
2139 if (!xprt_prepare_transmit(task))
2140 return;
2141 task->tk_status = 0;
2142 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2143 if (!xprt_connected(task->tk_xprt)) {
2144 task->tk_status = -ENOTCONN;
2145 return;
2146 }
2147 xprt_transmit(task);
2148 }
2149 xprt_end_transmit(task);
2150 }
2151
2152 /*
2153 * 5a. Handle cleanup after a transmission
2154 */
2155 static void
2156 call_transmit_status(struct rpc_task *task)
2157 {
2158 task->tk_action = call_status;
2159
2160 /*
2161 * Common case: success. Force the compiler to put this
2162 * test first.
2163 */
2164 if (rpc_task_transmitted(task)) {
2165 task->tk_status = 0;
2166 xprt_request_wait_receive(task);
2167 return;
2168 }
2169
2170 switch (task->tk_status) {
2171 default:
2172 break;
2173 case -EBADMSG:
2174 task->tk_status = 0;
2175 task->tk_action = call_encode;
2176 break;
2177 /*
2178 * Special cases: if we've been waiting on the
2179 * socket's write_space() callback, or if the
2180 * socket just returned a connection error,
2181 * then hold onto the transport lock.
2182 */
2183 case -ENOBUFS:
2184 rpc_delay(task, HZ>>2);
2185 fallthrough;
2186 case -EBADSLT:
2187 case -EAGAIN:
2188 task->tk_action = call_transmit;
2189 task->tk_status = 0;
2190 break;
2191 case -ECONNREFUSED:
2192 case -EHOSTDOWN:
2193 case -ENETDOWN:
2194 case -EHOSTUNREACH:
2195 case -ENETUNREACH:
2196 case -EPERM:
2197 if (RPC_IS_SOFTCONN(task)) {
2198 if (!task->tk_msg.rpc_proc->p_proc)
2199 trace_xprt_ping(task->tk_xprt,
2200 task->tk_status);
2201 rpc_call_rpcerror(task, task->tk_status);
2202 return;
2203 }
2204 fallthrough;
2205 case -ECONNRESET:
2206 case -ECONNABORTED:
2207 case -EADDRINUSE:
2208 case -ENOTCONN:
2209 case -EPIPE:
2210 task->tk_action = call_bind;
2211 task->tk_status = 0;
2212 break;
2213 }
2214 rpc_check_timeout(task);
2215 }
2216
2217 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
2218 static void call_bc_transmit(struct rpc_task *task);
2219 static void call_bc_transmit_status(struct rpc_task *task);
2220
2221 static void
2222 call_bc_encode(struct rpc_task *task)
2223 {
2224 xprt_request_enqueue_transmit(task);
2225 task->tk_action = call_bc_transmit;
2226 }
2227
2228 /*
2229 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2230 * addition, disconnect on connectivity errors.
2231 */
2232 static void
2233 call_bc_transmit(struct rpc_task *task)
2234 {
2235 task->tk_action = call_bc_transmit_status;
2236 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2237 if (!xprt_prepare_transmit(task))
2238 return;
2239 task->tk_status = 0;
2240 xprt_transmit(task);
2241 }
2242 xprt_end_transmit(task);
2243 }
2244
2245 static void
2246 call_bc_transmit_status(struct rpc_task *task)
2247 {
2248 struct rpc_rqst *req = task->tk_rqstp;
2249
2250 if (rpc_task_transmitted(task))
2251 task->tk_status = 0;
2252
2253 switch (task->tk_status) {
2254 case 0:
2255 /* Success */
2256 case -ENETDOWN:
2257 case -EHOSTDOWN:
2258 case -EHOSTUNREACH:
2259 case -ENETUNREACH:
2260 case -ECONNRESET:
2261 case -ECONNREFUSED:
2262 case -EADDRINUSE:
2263 case -ENOTCONN:
2264 case -EPIPE:
2265 break;
2266 case -ENOBUFS:
2267 rpc_delay(task, HZ>>2);
2268 fallthrough;
2269 case -EBADSLT:
2270 case -EAGAIN:
2271 task->tk_status = 0;
2272 task->tk_action = call_bc_transmit;
2273 return;
2274 case -ETIMEDOUT:
2275 /*
2276 * Problem reaching the server. Disconnect and let the
2277 * forechannel reestablish the connection. The server will
2278 * have to retransmit the backchannel request and we'll
2279 * reprocess it. Since these ops are idempotent, there's no
2280 * need to cache our reply at this time.
2281 */
2282 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2283 "error: %d\n", task->tk_status);
2284 xprt_conditional_disconnect(req->rq_xprt,
2285 req->rq_connect_cookie);
2286 break;
2287 default:
2288 /*
2289 * We were unable to reply and will have to drop the
2290 * request. The server should reconnect and retransmit.
2291 */
2292 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2293 "error: %d\n", task->tk_status);
2294 break;
2295 }
2296 task->tk_action = rpc_exit_task;
2297 }
2298 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2299
2300 /*
2301 * 6. Sort out the RPC call status
2302 */
2303 static void
2304 call_status(struct rpc_task *task)
2305 {
2306 struct rpc_clnt *clnt = task->tk_client;
2307 int status;
2308
2309 if (!task->tk_msg.rpc_proc->p_proc)
2310 trace_xprt_ping(task->tk_xprt, task->tk_status);
2311
2312 status = task->tk_status;
2313 if (status >= 0) {
2314 task->tk_action = call_decode;
2315 return;
2316 }
2317
2318 trace_rpc_call_status(task);
2319 task->tk_status = 0;
2320 switch(status) {
2321 case -EHOSTDOWN:
2322 case -ENETDOWN:
2323 case -EHOSTUNREACH:
2324 case -ENETUNREACH:
2325 case -EPERM:
2326 if (RPC_IS_SOFTCONN(task))
2327 goto out_exit;
2328 /*
2329 * Delay any retries for 3 seconds, then handle as if it
2330 * were a timeout.
2331 */
2332 rpc_delay(task, 3*HZ);
2333 fallthrough;
2334 case -ETIMEDOUT:
2335 break;
2336 case -ECONNREFUSED:
2337 case -ECONNRESET:
2338 case -ECONNABORTED:
2339 case -ENOTCONN:
2340 rpc_force_rebind(clnt);
2341 break;
2342 case -EADDRINUSE:
2343 rpc_delay(task, 3*HZ);
2344 fallthrough;
2345 case -EPIPE:
2346 case -EAGAIN:
2347 break;
2348 case -EIO:
2349 /* shutdown or soft timeout */
2350 goto out_exit;
2351 default:
2352 if (clnt->cl_chatty)
2353 printk("%s: RPC call returned error %d\n",
2354 clnt->cl_program->name, -status);
2355 goto out_exit;
2356 }
2357 task->tk_action = call_encode;
2358 if (status != -ECONNRESET && status != -ECONNABORTED)
2359 rpc_check_timeout(task);
2360 return;
2361 out_exit:
2362 rpc_call_rpcerror(task, status);
2363 }
2364
2365 static bool
2366 rpc_check_connected(const struct rpc_rqst *req)
2367 {
2368 /* No allocated request or transport? return true */
2369 if (!req || !req->rq_xprt)
2370 return true;
2371 return xprt_connected(req->rq_xprt);
2372 }
2373
2374 static void
2375 rpc_check_timeout(struct rpc_task *task)
2376 {
2377 struct rpc_clnt *clnt = task->tk_client;
2378
2379 if (RPC_SIGNALLED(task)) {
2380 rpc_call_rpcerror(task, -ERESTARTSYS);
2381 return;
2382 }
2383
2384 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2385 return;
2386
2387 trace_rpc_timeout_status(task);
2388 task->tk_timeouts++;
2389
2390 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2391 rpc_call_rpcerror(task, -ETIMEDOUT);
2392 return;
2393 }
2394
2395 if (RPC_IS_SOFT(task)) {
2396 /*
2397 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2398 * been sent, it should time out only if the transport
2399 * connection gets terminally broken.
2400 */
2401 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2402 rpc_check_connected(task->tk_rqstp))
2403 return;
2404
2405 if (clnt->cl_chatty) {
2406 pr_notice_ratelimited(
2407 "%s: server %s not responding, timed out\n",
2408 clnt->cl_program->name,
2409 task->tk_xprt->servername);
2410 }
2411 if (task->tk_flags & RPC_TASK_TIMEOUT)
2412 rpc_call_rpcerror(task, -ETIMEDOUT);
2413 else
2414 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2415 return;
2416 }
2417
2418 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2419 task->tk_flags |= RPC_CALL_MAJORSEEN;
2420 if (clnt->cl_chatty) {
2421 pr_notice_ratelimited(
2422 "%s: server %s not responding, still trying\n",
2423 clnt->cl_program->name,
2424 task->tk_xprt->servername);
2425 }
2426 }
2427 rpc_force_rebind(clnt);
2428 /*
2429 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2430 * event? RFC2203 requires the server to drop all such requests.
2431 */
2432 rpcauth_invalcred(task);
2433 }
2434
2435 /*
2436 * 7. Decode the RPC reply
2437 */
2438 static void
2439 call_decode(struct rpc_task *task)
2440 {
2441 struct rpc_clnt *clnt = task->tk_client;
2442 struct rpc_rqst *req = task->tk_rqstp;
2443 struct xdr_stream xdr;
2444 int err;
2445
2446 if (!task->tk_msg.rpc_proc->p_decode) {
2447 task->tk_action = rpc_exit_task;
2448 return;
2449 }
2450
2451 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2452 if (clnt->cl_chatty) {
2453 pr_notice_ratelimited("%s: server %s OK\n",
2454 clnt->cl_program->name,
2455 task->tk_xprt->servername);
2456 }
2457 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2458 }
2459
2460 /*
2461 * Ensure that we see all writes made by xprt_complete_rqst()
2462 * before it changed req->rq_reply_bytes_recvd.
2463 */
2464 smp_rmb();
2465
2466 /*
2467 * Did we ever call xprt_complete_rqst()? If not, we should assume
2468 * the message is incomplete.
2469 */
2470 err = -EAGAIN;
2471 if (!req->rq_reply_bytes_recvd)
2472 goto out;
2473
2474 req->rq_rcv_buf.len = req->rq_private_buf.len;
2475 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2476
2477 /* Check that the softirq receive buffer is valid */
2478 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2479 sizeof(req->rq_rcv_buf)) != 0);
2480
2481 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2482 req->rq_rcv_buf.head[0].iov_base, req);
2483 err = rpc_decode_header(task, &xdr);
2484 out:
2485 switch (err) {
2486 case 0:
2487 task->tk_action = rpc_exit_task;
2488 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2489 return;
2490 case -EAGAIN:
2491 task->tk_status = 0;
2492 if (task->tk_client->cl_discrtry)
2493 xprt_conditional_disconnect(req->rq_xprt,
2494 req->rq_connect_cookie);
2495 task->tk_action = call_encode;
2496 rpc_check_timeout(task);
2497 break;
2498 case -EKEYREJECTED:
2499 task->tk_action = call_reserve;
2500 rpc_check_timeout(task);
2501 rpcauth_invalcred(task);
2502 /* Ensure we obtain a new XID if we retry! */
2503 xprt_release(task);
2504 }
2505 }
2506
2507 static int
2508 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2509 {
2510 struct rpc_clnt *clnt = task->tk_client;
2511 struct rpc_rqst *req = task->tk_rqstp;
2512 __be32 *p;
2513 int error;
2514
2515 error = -EMSGSIZE;
2516 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2517 if (!p)
2518 goto out_fail;
2519 *p++ = req->rq_xid;
2520 *p++ = rpc_call;
2521 *p++ = cpu_to_be32(RPC_VERSION);
2522 *p++ = cpu_to_be32(clnt->cl_prog);
2523 *p++ = cpu_to_be32(clnt->cl_vers);
2524 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2525
2526 error = rpcauth_marshcred(task, xdr);
2527 if (error < 0)
2528 goto out_fail;
2529 return 0;
2530 out_fail:
2531 trace_rpc_bad_callhdr(task);
2532 rpc_call_rpcerror(task, error);
2533 return error;
2534 }
2535
2536 static noinline int
2537 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2538 {
2539 struct rpc_clnt *clnt = task->tk_client;
2540 int error;
2541 __be32 *p;
2542
2543 /* RFC-1014 says that the representation of XDR data must be a
2544 * multiple of four bytes
2545 * - if it isn't pointer subtraction in the NFS client may give
2546 * undefined results
2547 */
2548 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2549 goto out_unparsable;
2550
2551 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2552 if (!p)
2553 goto out_unparsable;
2554 p++; /* skip XID */
2555 if (*p++ != rpc_reply)
2556 goto out_unparsable;
2557 if (*p++ != rpc_msg_accepted)
2558 goto out_msg_denied;
2559
2560 error = rpcauth_checkverf(task, xdr);
2561 if (error)
2562 goto out_verifier;
2563
2564 p = xdr_inline_decode(xdr, sizeof(*p));
2565 if (!p)
2566 goto out_unparsable;
2567 switch (*p) {
2568 case rpc_success:
2569 return 0;
2570 case rpc_prog_unavail:
2571 trace_rpc__prog_unavail(task);
2572 error = -EPFNOSUPPORT;
2573 goto out_err;
2574 case rpc_prog_mismatch:
2575 trace_rpc__prog_mismatch(task);
2576 error = -EPROTONOSUPPORT;
2577 goto out_err;
2578 case rpc_proc_unavail:
2579 trace_rpc__proc_unavail(task);
2580 error = -EOPNOTSUPP;
2581 goto out_err;
2582 case rpc_garbage_args:
2583 case rpc_system_err:
2584 trace_rpc__garbage_args(task);
2585 error = -EIO;
2586 break;
2587 default:
2588 goto out_unparsable;
2589 }
2590
2591 out_garbage:
2592 clnt->cl_stats->rpcgarbage++;
2593 if (task->tk_garb_retry) {
2594 task->tk_garb_retry--;
2595 task->tk_action = call_encode;
2596 return -EAGAIN;
2597 }
2598 out_err:
2599 rpc_call_rpcerror(task, error);
2600 return error;
2601
2602 out_unparsable:
2603 trace_rpc__unparsable(task);
2604 error = -EIO;
2605 goto out_garbage;
2606
2607 out_verifier:
2608 trace_rpc_bad_verifier(task);
2609 goto out_garbage;
2610
2611 out_msg_denied:
2612 error = -EACCES;
2613 p = xdr_inline_decode(xdr, sizeof(*p));
2614 if (!p)
2615 goto out_unparsable;
2616 switch (*p++) {
2617 case rpc_auth_error:
2618 break;
2619 case rpc_mismatch:
2620 trace_rpc__mismatch(task);
2621 error = -EPROTONOSUPPORT;
2622 goto out_err;
2623 default:
2624 goto out_unparsable;
2625 }
2626
2627 p = xdr_inline_decode(xdr, sizeof(*p));
2628 if (!p)
2629 goto out_unparsable;
2630 switch (*p++) {
2631 case rpc_autherr_rejectedcred:
2632 case rpc_autherr_rejectedverf:
2633 case rpcsec_gsserr_credproblem:
2634 case rpcsec_gsserr_ctxproblem:
2635 if (!task->tk_cred_retry)
2636 break;
2637 task->tk_cred_retry--;
2638 trace_rpc__stale_creds(task);
2639 return -EKEYREJECTED;
2640 case rpc_autherr_badcred:
2641 case rpc_autherr_badverf:
2642 /* possibly garbled cred/verf? */
2643 if (!task->tk_garb_retry)
2644 break;
2645 task->tk_garb_retry--;
2646 trace_rpc__bad_creds(task);
2647 task->tk_action = call_encode;
2648 return -EAGAIN;
2649 case rpc_autherr_tooweak:
2650 trace_rpc__auth_tooweak(task);
2651 pr_warn("RPC: server %s requires stronger authentication.\n",
2652 task->tk_xprt->servername);
2653 break;
2654 default:
2655 goto out_unparsable;
2656 }
2657 goto out_err;
2658 }
2659
2660 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2661 const void *obj)
2662 {
2663 }
2664
2665 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2666 void *obj)
2667 {
2668 return 0;
2669 }
2670
2671 static const struct rpc_procinfo rpcproc_null = {
2672 .p_encode = rpcproc_encode_null,
2673 .p_decode = rpcproc_decode_null,
2674 };
2675
2676 static int rpc_ping(struct rpc_clnt *clnt)
2677 {
2678 struct rpc_message msg = {
2679 .rpc_proc = &rpcproc_null,
2680 };
2681 int err;
2682 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2683 RPC_TASK_NULLCREDS);
2684 return err;
2685 }
2686
2687 static
2688 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2689 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2690 const struct rpc_call_ops *ops, void *data)
2691 {
2692 struct rpc_message msg = {
2693 .rpc_proc = &rpcproc_null,
2694 };
2695 struct rpc_task_setup task_setup_data = {
2696 .rpc_client = clnt,
2697 .rpc_xprt = xprt,
2698 .rpc_message = &msg,
2699 .rpc_op_cred = cred,
2700 .callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
2701 .callback_data = data,
2702 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2703 RPC_TASK_NULLCREDS,
2704 };
2705
2706 return rpc_run_task(&task_setup_data);
2707 }
2708
2709 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2710 {
2711 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2712 }
2713 EXPORT_SYMBOL_GPL(rpc_call_null);
2714
2715 struct rpc_cb_add_xprt_calldata {
2716 struct rpc_xprt_switch *xps;
2717 struct rpc_xprt *xprt;
2718 };
2719
2720 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2721 {
2722 struct rpc_cb_add_xprt_calldata *data = calldata;
2723
2724 if (task->tk_status == 0)
2725 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2726 }
2727
2728 static void rpc_cb_add_xprt_release(void *calldata)
2729 {
2730 struct rpc_cb_add_xprt_calldata *data = calldata;
2731
2732 xprt_put(data->xprt);
2733 xprt_switch_put(data->xps);
2734 kfree(data);
2735 }
2736
2737 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2738 .rpc_call_done = rpc_cb_add_xprt_done,
2739 .rpc_release = rpc_cb_add_xprt_release,
2740 };
2741
2742 /**
2743 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2744 * @clnt: pointer to struct rpc_clnt
2745 * @xps: pointer to struct rpc_xprt_switch,
2746 * @xprt: pointer struct rpc_xprt
2747 * @dummy: unused
2748 */
2749 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2750 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2751 void *dummy)
2752 {
2753 struct rpc_cb_add_xprt_calldata *data;
2754 struct rpc_task *task;
2755
2756 data = kmalloc(sizeof(*data), GFP_NOFS);
2757 if (!data)
2758 return -ENOMEM;
2759 data->xps = xprt_switch_get(xps);
2760 data->xprt = xprt_get(xprt);
2761 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2762 rpc_cb_add_xprt_release(data);
2763 goto success;
2764 }
2765
2766 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2767 &rpc_cb_add_xprt_call_ops, data);
2768
2769 rpc_put_task(task);
2770 success:
2771 return 1;
2772 }
2773 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2774
2775 /**
2776 * rpc_clnt_setup_test_and_add_xprt()
2777 *
2778 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2779 * 1) caller of the test function must dereference the rpc_xprt_switch
2780 * and the rpc_xprt.
2781 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2782 * the rpc_call_done routine.
2783 *
2784 * Upon success (return of 1), the test function adds the new
2785 * transport to the rpc_clnt xprt switch
2786 *
2787 * @clnt: struct rpc_clnt to get the new transport
2788 * @xps: the rpc_xprt_switch to hold the new transport
2789 * @xprt: the rpc_xprt to test
2790 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2791 * and test function call data
2792 */
2793 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2794 struct rpc_xprt_switch *xps,
2795 struct rpc_xprt *xprt,
2796 void *data)
2797 {
2798 struct rpc_task *task;
2799 struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
2800 int status = -EADDRINUSE;
2801
2802 xprt = xprt_get(xprt);
2803 xprt_switch_get(xps);
2804
2805 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2806 goto out_err;
2807
2808 /* Test the connection */
2809 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2810 if (IS_ERR(task)) {
2811 status = PTR_ERR(task);
2812 goto out_err;
2813 }
2814 status = task->tk_status;
2815 rpc_put_task(task);
2816
2817 if (status < 0)
2818 goto out_err;
2819
2820 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2821 xtest->add_xprt_test(clnt, xprt, xtest->data);
2822
2823 xprt_put(xprt);
2824 xprt_switch_put(xps);
2825
2826 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
2827 return 1;
2828 out_err:
2829 xprt_put(xprt);
2830 xprt_switch_put(xps);
2831 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n",
2832 status, xprt->address_strings[RPC_DISPLAY_ADDR]);
2833 return status;
2834 }
2835 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
2836
2837 /**
2838 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
2839 * @clnt: pointer to struct rpc_clnt
2840 * @xprtargs: pointer to struct xprt_create
2841 * @setup: callback to test and/or set up the connection
2842 * @data: pointer to setup function data
2843 *
2844 * Creates a new transport using the parameters set in args and
2845 * adds it to clnt.
2846 * If ping is set, then test that connectivity succeeds before
2847 * adding the new transport.
2848 *
2849 */
2850 int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
2851 struct xprt_create *xprtargs,
2852 int (*setup)(struct rpc_clnt *,
2853 struct rpc_xprt_switch *,
2854 struct rpc_xprt *,
2855 void *),
2856 void *data)
2857 {
2858 struct rpc_xprt_switch *xps;
2859 struct rpc_xprt *xprt;
2860 unsigned long connect_timeout;
2861 unsigned long reconnect_timeout;
2862 unsigned char resvport, reuseport;
2863 int ret = 0;
2864
2865 rcu_read_lock();
2866 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2867 xprt = xprt_iter_xprt(&clnt->cl_xpi);
2868 if (xps == NULL || xprt == NULL) {
2869 rcu_read_unlock();
2870 xprt_switch_put(xps);
2871 return -EAGAIN;
2872 }
2873 resvport = xprt->resvport;
2874 reuseport = xprt->reuseport;
2875 connect_timeout = xprt->connect_timeout;
2876 reconnect_timeout = xprt->max_reconnect_timeout;
2877 rcu_read_unlock();
2878
2879 xprt = xprt_create_transport(xprtargs);
2880 if (IS_ERR(xprt)) {
2881 ret = PTR_ERR(xprt);
2882 goto out_put_switch;
2883 }
2884 xprt->resvport = resvport;
2885 xprt->reuseport = reuseport;
2886 if (xprt->ops->set_connect_timeout != NULL)
2887 xprt->ops->set_connect_timeout(xprt,
2888 connect_timeout,
2889 reconnect_timeout);
2890
2891 rpc_xprt_switch_set_roundrobin(xps);
2892 if (setup) {
2893 ret = setup(clnt, xps, xprt, data);
2894 if (ret != 0)
2895 goto out_put_xprt;
2896 }
2897 rpc_xprt_switch_add_xprt(xps, xprt);
2898 out_put_xprt:
2899 xprt_put(xprt);
2900 out_put_switch:
2901 xprt_switch_put(xps);
2902 return ret;
2903 }
2904 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
2905
2906 struct connect_timeout_data {
2907 unsigned long connect_timeout;
2908 unsigned long reconnect_timeout;
2909 };
2910
2911 static int
2912 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
2913 struct rpc_xprt *xprt,
2914 void *data)
2915 {
2916 struct connect_timeout_data *timeo = data;
2917
2918 if (xprt->ops->set_connect_timeout)
2919 xprt->ops->set_connect_timeout(xprt,
2920 timeo->connect_timeout,
2921 timeo->reconnect_timeout);
2922 return 0;
2923 }
2924
2925 void
2926 rpc_set_connect_timeout(struct rpc_clnt *clnt,
2927 unsigned long connect_timeout,
2928 unsigned long reconnect_timeout)
2929 {
2930 struct connect_timeout_data timeout = {
2931 .connect_timeout = connect_timeout,
2932 .reconnect_timeout = reconnect_timeout,
2933 };
2934 rpc_clnt_iterate_for_each_xprt(clnt,
2935 rpc_xprt_set_connect_timeout,
2936 &timeout);
2937 }
2938 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
2939
2940 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
2941 {
2942 rcu_read_lock();
2943 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2944 rcu_read_unlock();
2945 }
2946 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
2947
2948 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
2949 {
2950 rcu_read_lock();
2951 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
2952 xprt);
2953 rcu_read_unlock();
2954 }
2955 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
2956
2957 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
2958 const struct sockaddr *sap)
2959 {
2960 struct rpc_xprt_switch *xps;
2961 bool ret;
2962
2963 rcu_read_lock();
2964 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
2965 ret = rpc_xprt_switch_has_addr(xps, sap);
2966 rcu_read_unlock();
2967 return ret;
2968 }
2969 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
2970
2971 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
2972 static void rpc_show_header(void)
2973 {
2974 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
2975 "-timeout ---ops--\n");
2976 }
2977
2978 static void rpc_show_task(const struct rpc_clnt *clnt,
2979 const struct rpc_task *task)
2980 {
2981 const char *rpc_waitq = "none";
2982
2983 if (RPC_IS_QUEUED(task))
2984 rpc_waitq = rpc_qname(task->tk_waitqueue);
2985
2986 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
2987 task->tk_pid, task->tk_flags, task->tk_status,
2988 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
2989 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
2990 task->tk_action, rpc_waitq);
2991 }
2992
2993 void rpc_show_tasks(struct net *net)
2994 {
2995 struct rpc_clnt *clnt;
2996 struct rpc_task *task;
2997 int header = 0;
2998 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
2999
3000 spin_lock(&sn->rpc_client_lock);
3001 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3002 spin_lock(&clnt->cl_lock);
3003 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3004 if (!header) {
3005 rpc_show_header();
3006 header++;
3007 }
3008 rpc_show_task(clnt, task);
3009 }
3010 spin_unlock(&clnt->cl_lock);
3011 }
3012 spin_unlock(&sn->rpc_client_lock);
3013 }
3014 #endif
3015
3016 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3017 static int
3018 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3019 struct rpc_xprt *xprt,
3020 void *dummy)
3021 {
3022 return xprt_enable_swap(xprt);
3023 }
3024
3025 int
3026 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3027 {
3028 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3029 return rpc_clnt_iterate_for_each_xprt(clnt,
3030 rpc_clnt_swap_activate_callback, NULL);
3031 return 0;
3032 }
3033 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3034
3035 static int
3036 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3037 struct rpc_xprt *xprt,
3038 void *dummy)
3039 {
3040 xprt_disable_swap(xprt);
3041 return 0;
3042 }
3043
3044 void
3045 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3046 {
3047 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3048 rpc_clnt_iterate_for_each_xprt(clnt,
3049 rpc_clnt_swap_deactivate_callback, NULL);
3050 }
3051 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3052 #endif /* CONFIG_SUNRPC_SWAP */
Linux with added FPC-III support