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ARM: dma-api: fix max_pfn off-by-one error in __dma_supported()
[linux/fpc-iii.git] / net / sunrpc / clnt.c
bloba3379765605d160dee186bb6743ed8e53756df07
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/kallsyms.h>
25 #include <linux/mm.h>
26 #include <linux/namei.h>
27 #include <linux/mount.h>
28 #include <linux/slab.h>
29 #include <linux/rcupdate.h>
30 #include <linux/utsname.h>
31 #include <linux/workqueue.h>
32 #include <linux/in.h>
33 #include <linux/in6.h>
34 #include <linux/un.h>
35
36 #include <linux/sunrpc/clnt.h>
37 #include <linux/sunrpc/addr.h>
38 #include <linux/sunrpc/rpc_pipe_fs.h>
39 #include <linux/sunrpc/metrics.h>
40 #include <linux/sunrpc/bc_xprt.h>
41 #include <trace/events/sunrpc.h>
42
43 #include "sunrpc.h"
44 #include "netns.h"
45
46 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
47 # define RPCDBG_FACILITY RPCDBG_CALL
48 #endif
49
50 #define dprint_status(t) \
51 dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
52 __func__, t->tk_status)
53
54 /*
55 * All RPC clients are linked into this list
56 */
57
58 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
59
60
61 static void call_start(struct rpc_task *task);
62 static void call_reserve(struct rpc_task *task);
63 static void call_reserveresult(struct rpc_task *task);
64 static void call_allocate(struct rpc_task *task);
65 static void call_encode(struct rpc_task *task);
66 static void call_decode(struct rpc_task *task);
67 static void call_bind(struct rpc_task *task);
68 static void call_bind_status(struct rpc_task *task);
69 static void call_transmit(struct rpc_task *task);
70 static void call_status(struct rpc_task *task);
71 static void call_transmit_status(struct rpc_task *task);
72 static void call_refresh(struct rpc_task *task);
73 static void call_refreshresult(struct rpc_task *task);
74 static void call_connect(struct rpc_task *task);
75 static void call_connect_status(struct rpc_task *task);
76
77 static int rpc_encode_header(struct rpc_task *task,
78 struct xdr_stream *xdr);
79 static int rpc_decode_header(struct rpc_task *task,
80 struct xdr_stream *xdr);
81 static int rpc_ping(struct rpc_clnt *clnt);
82 static void rpc_check_timeout(struct rpc_task *task);
83
84 static void rpc_register_client(struct rpc_clnt *clnt)
85 {
86 struct net *net = rpc_net_ns(clnt);
87 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
88
89 spin_lock(&sn->rpc_client_lock);
90 list_add(&clnt->cl_clients, &sn->all_clients);
91 spin_unlock(&sn->rpc_client_lock);
92 }
93
94 static void rpc_unregister_client(struct rpc_clnt *clnt)
95 {
96 struct net *net = rpc_net_ns(clnt);
97 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
98
99 spin_lock(&sn->rpc_client_lock);
100 list_del(&clnt->cl_clients);
101 spin_unlock(&sn->rpc_client_lock);
102 }
103
104 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
105 {
106 rpc_remove_client_dir(clnt);
107 }
108
109 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
110 {
111 struct net *net = rpc_net_ns(clnt);
112 struct super_block *pipefs_sb;
113
114 pipefs_sb = rpc_get_sb_net(net);
115 if (pipefs_sb) {
116 __rpc_clnt_remove_pipedir(clnt);
117 rpc_put_sb_net(net);
118 }
119 }
120
121 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
122 struct rpc_clnt *clnt)
123 {
124 static uint32_t clntid;
125 const char *dir_name = clnt->cl_program->pipe_dir_name;
126 char name[15];
127 struct dentry *dir, *dentry;
128
129 dir = rpc_d_lookup_sb(sb, dir_name);
130 if (dir == NULL) {
131 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
132 return dir;
133 }
134 for (;;) {
135 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
136 name[sizeof(name) - 1] = '\0';
137 dentry = rpc_create_client_dir(dir, name, clnt);
138 if (!IS_ERR(dentry))
139 break;
140 if (dentry == ERR_PTR(-EEXIST))
141 continue;
142 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
143 " %s/%s, error %ld\n",
144 dir_name, name, PTR_ERR(dentry));
145 break;
146 }
147 dput(dir);
148 return dentry;
149 }
150
151 static int
152 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
153 {
154 struct dentry *dentry;
155
156 if (clnt->cl_program->pipe_dir_name != NULL) {
157 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
158 if (IS_ERR(dentry))
159 return PTR_ERR(dentry);
160 }
161 return 0;
162 }
163
164 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
165 {
166 if (clnt->cl_program->pipe_dir_name == NULL)
167 return 1;
168
169 switch (event) {
170 case RPC_PIPEFS_MOUNT:
171 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
172 return 1;
173 if (atomic_read(&clnt->cl_count) == 0)
174 return 1;
175 break;
176 case RPC_PIPEFS_UMOUNT:
177 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
178 return 1;
179 break;
180 }
181 return 0;
182 }
183
184 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
185 struct super_block *sb)
186 {
187 struct dentry *dentry;
188
189 switch (event) {
190 case RPC_PIPEFS_MOUNT:
191 dentry = rpc_setup_pipedir_sb(sb, clnt);
192 if (!dentry)
193 return -ENOENT;
194 if (IS_ERR(dentry))
195 return PTR_ERR(dentry);
196 break;
197 case RPC_PIPEFS_UMOUNT:
198 __rpc_clnt_remove_pipedir(clnt);
199 break;
200 default:
201 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
202 return -ENOTSUPP;
203 }
204 return 0;
205 }
206
207 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
208 struct super_block *sb)
209 {
210 int error = 0;
211
212 for (;; clnt = clnt->cl_parent) {
213 if (!rpc_clnt_skip_event(clnt, event))
214 error = __rpc_clnt_handle_event(clnt, event, sb);
215 if (error || clnt == clnt->cl_parent)
216 break;
217 }
218 return error;
219 }
220
221 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
222 {
223 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
224 struct rpc_clnt *clnt;
225
226 spin_lock(&sn->rpc_client_lock);
227 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
228 if (rpc_clnt_skip_event(clnt, event))
229 continue;
230 spin_unlock(&sn->rpc_client_lock);
231 return clnt;
232 }
233 spin_unlock(&sn->rpc_client_lock);
234 return NULL;
235 }
236
237 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
238 void *ptr)
239 {
240 struct super_block *sb = ptr;
241 struct rpc_clnt *clnt;
242 int error = 0;
243
244 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
245 error = __rpc_pipefs_event(clnt, event, sb);
246 if (error)
247 break;
248 }
249 return error;
250 }
251
252 static struct notifier_block rpc_clients_block = {
253 .notifier_call = rpc_pipefs_event,
254 .priority = SUNRPC_PIPEFS_RPC_PRIO,
255 };
256
257 int rpc_clients_notifier_register(void)
258 {
259 return rpc_pipefs_notifier_register(&rpc_clients_block);
260 }
261
262 void rpc_clients_notifier_unregister(void)
263 {
264 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
265 }
266
267 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
268 struct rpc_xprt *xprt,
269 const struct rpc_timeout *timeout)
270 {
271 struct rpc_xprt *old;
272
273 spin_lock(&clnt->cl_lock);
274 old = rcu_dereference_protected(clnt->cl_xprt,
275 lockdep_is_held(&clnt->cl_lock));
276
277 if (!xprt_bound(xprt))
278 clnt->cl_autobind = 1;
279
280 clnt->cl_timeout = timeout;
281 rcu_assign_pointer(clnt->cl_xprt, xprt);
282 spin_unlock(&clnt->cl_lock);
283
284 return old;
285 }
286
287 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
288 {
289 clnt->cl_nodelen = strlcpy(clnt->cl_nodename,
290 nodename, sizeof(clnt->cl_nodename));
291 }
292
293 static int rpc_client_register(struct rpc_clnt *clnt,
294 rpc_authflavor_t pseudoflavor,
295 const char *client_name)
296 {
297 struct rpc_auth_create_args auth_args = {
298 .pseudoflavor = pseudoflavor,
299 .target_name = client_name,
300 };
301 struct rpc_auth *auth;
302 struct net *net = rpc_net_ns(clnt);
303 struct super_block *pipefs_sb;
304 int err;
305
306 rpc_clnt_debugfs_register(clnt);
307
308 pipefs_sb = rpc_get_sb_net(net);
309 if (pipefs_sb) {
310 err = rpc_setup_pipedir(pipefs_sb, clnt);
311 if (err)
312 goto out;
313 }
314
315 rpc_register_client(clnt);
316 if (pipefs_sb)
317 rpc_put_sb_net(net);
318
319 auth = rpcauth_create(&auth_args, clnt);
320 if (IS_ERR(auth)) {
321 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
322 pseudoflavor);
323 err = PTR_ERR(auth);
324 goto err_auth;
325 }
326 return 0;
327 err_auth:
328 pipefs_sb = rpc_get_sb_net(net);
329 rpc_unregister_client(clnt);
330 __rpc_clnt_remove_pipedir(clnt);
331 out:
332 if (pipefs_sb)
333 rpc_put_sb_net(net);
334 rpc_clnt_debugfs_unregister(clnt);
335 return err;
336 }
337
338 static DEFINE_IDA(rpc_clids);
339
340 void rpc_cleanup_clids(void)
341 {
342 ida_destroy(&rpc_clids);
343 }
344
345 static int rpc_alloc_clid(struct rpc_clnt *clnt)
346 {
347 int clid;
348
349 clid = ida_simple_get(&rpc_clids, 0, 0, GFP_KERNEL);
350 if (clid < 0)
351 return clid;
352 clnt->cl_clid = clid;
353 return 0;
354 }
355
356 static void rpc_free_clid(struct rpc_clnt *clnt)
357 {
358 ida_simple_remove(&rpc_clids, clnt->cl_clid);
359 }
360
361 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
362 struct rpc_xprt_switch *xps,
363 struct rpc_xprt *xprt,
364 struct rpc_clnt *parent)
365 {
366 const struct rpc_program *program = args->program;
367 const struct rpc_version *version;
368 struct rpc_clnt *clnt = NULL;
369 const struct rpc_timeout *timeout;
370 const char *nodename = args->nodename;
371 int err;
372
373 /* sanity check the name before trying to print it */
374 dprintk("RPC: creating %s client for %s (xprt %p)\n",
375 program->name, args->servername, xprt);
376
377 err = rpciod_up();
378 if (err)
379 goto out_no_rpciod;
380
381 err = -EINVAL;
382 if (args->version >= program->nrvers)
383 goto out_err;
384 version = program->version[args->version];
385 if (version == NULL)
386 goto out_err;
387
388 err = -ENOMEM;
389 clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
390 if (!clnt)
391 goto out_err;
392 clnt->cl_parent = parent ? : clnt;
393
394 err = rpc_alloc_clid(clnt);
395 if (err)
396 goto out_no_clid;
397
398 clnt->cl_cred = get_cred(args->cred);
399 clnt->cl_procinfo = version->procs;
400 clnt->cl_maxproc = version->nrprocs;
401 clnt->cl_prog = args->prognumber ? : program->number;
402 clnt->cl_vers = version->number;
403 clnt->cl_stats = program->stats;
404 clnt->cl_metrics = rpc_alloc_iostats(clnt);
405 rpc_init_pipe_dir_head(&clnt->cl_pipedir_objects);
406 err = -ENOMEM;
407 if (clnt->cl_metrics == NULL)
408 goto out_no_stats;
409 clnt->cl_program = program;
410 INIT_LIST_HEAD(&clnt->cl_tasks);
411 spin_lock_init(&clnt->cl_lock);
412
413 timeout = xprt->timeout;
414 if (args->timeout != NULL) {
415 memcpy(&clnt->cl_timeout_default, args->timeout,
416 sizeof(clnt->cl_timeout_default));
417 timeout = &clnt->cl_timeout_default;
418 }
419
420 rpc_clnt_set_transport(clnt, xprt, timeout);
421 xprt_iter_init(&clnt->cl_xpi, xps);
422 xprt_switch_put(xps);
423
424 clnt->cl_rtt = &clnt->cl_rtt_default;
425 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
426
427 atomic_set(&clnt->cl_count, 1);
428
429 if (nodename == NULL)
430 nodename = utsname()->nodename;
431 /* save the nodename */
432 rpc_clnt_set_nodename(clnt, nodename);
433
434 err = rpc_client_register(clnt, args->authflavor, args->client_name);
435 if (err)
436 goto out_no_path;
437 if (parent)
438 atomic_inc(&parent->cl_count);
439 return clnt;
440
441 out_no_path:
442 rpc_free_iostats(clnt->cl_metrics);
443 out_no_stats:
444 put_cred(clnt->cl_cred);
445 rpc_free_clid(clnt);
446 out_no_clid:
447 kfree(clnt);
448 out_err:
449 rpciod_down();
450 out_no_rpciod:
451 xprt_switch_put(xps);
452 xprt_put(xprt);
453 return ERR_PTR(err);
454 }
455
456 static 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 }
488
489 clnt->cl_softrtry = 1;
490 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
491 clnt->cl_softrtry = 0;
492 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
493 clnt->cl_softerr = 1;
494 }
495
496 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
497 clnt->cl_autobind = 1;
498 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
499 clnt->cl_noretranstimeo = 1;
500 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
501 clnt->cl_discrtry = 1;
502 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
503 clnt->cl_chatty = 1;
504
505 return clnt;
506 }
507
508 /**
509 * rpc_create - create an RPC client and transport with one call
510 * @args: rpc_clnt create argument structure
511 *
512 * Creates and initializes an RPC transport and an RPC client.
513 *
514 * It can ping the server in order to determine if it is up, and to see if
515 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
516 * this behavior so asynchronous tasks can also use rpc_create.
517 */
518 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
519 {
520 struct rpc_xprt *xprt;
521 struct xprt_create xprtargs = {
522 .net = args->net,
523 .ident = args->protocol,
524 .srcaddr = args->saddress,
525 .dstaddr = args->address,
526 .addrlen = args->addrsize,
527 .servername = args->servername,
528 .bc_xprt = args->bc_xprt,
529 };
530 char servername[48];
531 struct rpc_clnt *clnt;
532 int i;
533
534 if (args->bc_xprt) {
535 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
536 xprt = args->bc_xprt->xpt_bc_xprt;
537 if (xprt) {
538 xprt_get(xprt);
539 return rpc_create_xprt(args, xprt);
540 }
541 }
542
543 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
544 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
545 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
546 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
547 /*
548 * If the caller chooses not to specify a hostname, whip
549 * up a string representation of the passed-in address.
550 */
551 if (xprtargs.servername == NULL) {
552 struct sockaddr_un *sun =
553 (struct sockaddr_un *)args->address;
554 struct sockaddr_in *sin =
555 (struct sockaddr_in *)args->address;
556 struct sockaddr_in6 *sin6 =
557 (struct sockaddr_in6 *)args->address;
558
559 servername[0] = '\0';
560 switch (args->address->sa_family) {
561 case AF_LOCAL:
562 snprintf(servername, sizeof(servername), "%s",
563 sun->sun_path);
564 break;
565 case AF_INET:
566 snprintf(servername, sizeof(servername), "%pI4",
567 &sin->sin_addr.s_addr);
568 break;
569 case AF_INET6:
570 snprintf(servername, sizeof(servername), "%pI6",
571 &sin6->sin6_addr);
572 break;
573 default:
574 /* caller wants default server name, but
575 * address family isn't recognized. */
576 return ERR_PTR(-EINVAL);
577 }
578 xprtargs.servername = servername;
579 }
580
581 xprt = xprt_create_transport(&xprtargs);
582 if (IS_ERR(xprt))
583 return (struct rpc_clnt *)xprt;
584
585 /*
586 * By default, kernel RPC client connects from a reserved port.
587 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
588 * but it is always enabled for rpciod, which handles the connect
589 * operation.
590 */
591 xprt->resvport = 1;
592 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
593 xprt->resvport = 0;
594 xprt->reuseport = 0;
595 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
596 xprt->reuseport = 1;
597
598 clnt = rpc_create_xprt(args, xprt);
599 if (IS_ERR(clnt) || args->nconnect <= 1)
600 return clnt;
601
602 for (i = 0; i < args->nconnect - 1; i++) {
603 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
604 break;
605 }
606 return clnt;
607 }
608 EXPORT_SYMBOL_GPL(rpc_create);
609
610 /*
611 * This function clones the RPC client structure. It allows us to share the
612 * same transport while varying parameters such as the authentication
613 * flavour.
614 */
615 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
616 struct rpc_clnt *clnt)
617 {
618 struct rpc_xprt_switch *xps;
619 struct rpc_xprt *xprt;
620 struct rpc_clnt *new;
621 int err;
622
623 err = -ENOMEM;
624 rcu_read_lock();
625 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
626 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
627 rcu_read_unlock();
628 if (xprt == NULL || xps == NULL) {
629 xprt_put(xprt);
630 xprt_switch_put(xps);
631 goto out_err;
632 }
633 args->servername = xprt->servername;
634 args->nodename = clnt->cl_nodename;
635
636 new = rpc_new_client(args, xps, xprt, clnt);
637 if (IS_ERR(new)) {
638 err = PTR_ERR(new);
639 goto out_err;
640 }
641
642 /* Turn off autobind on clones */
643 new->cl_autobind = 0;
644 new->cl_softrtry = clnt->cl_softrtry;
645 new->cl_softerr = clnt->cl_softerr;
646 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
647 new->cl_discrtry = clnt->cl_discrtry;
648 new->cl_chatty = clnt->cl_chatty;
649 new->cl_principal = clnt->cl_principal;
650 return new;
651
652 out_err:
653 dprintk("RPC: %s: returned error %d\n", __func__, err);
654 return ERR_PTR(err);
655 }
656
657 /**
658 * rpc_clone_client - Clone an RPC client structure
659 *
660 * @clnt: RPC client whose parameters are copied
661 *
662 * Returns a fresh RPC client or an ERR_PTR.
663 */
664 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
665 {
666 struct rpc_create_args args = {
667 .program = clnt->cl_program,
668 .prognumber = clnt->cl_prog,
669 .version = clnt->cl_vers,
670 .authflavor = clnt->cl_auth->au_flavor,
671 .cred = clnt->cl_cred,
672 };
673 return __rpc_clone_client(&args, clnt);
674 }
675 EXPORT_SYMBOL_GPL(rpc_clone_client);
676
677 /**
678 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
679 *
680 * @clnt: RPC client whose parameters are copied
681 * @flavor: security flavor for new client
682 *
683 * Returns a fresh RPC client or an ERR_PTR.
684 */
685 struct rpc_clnt *
686 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
687 {
688 struct rpc_create_args args = {
689 .program = clnt->cl_program,
690 .prognumber = clnt->cl_prog,
691 .version = clnt->cl_vers,
692 .authflavor = flavor,
693 .cred = clnt->cl_cred,
694 };
695 return __rpc_clone_client(&args, clnt);
696 }
697 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
698
699 /**
700 * rpc_switch_client_transport: switch the RPC transport on the fly
701 * @clnt: pointer to a struct rpc_clnt
702 * @args: pointer to the new transport arguments
703 * @timeout: pointer to the new timeout parameters
704 *
705 * This function allows the caller to switch the RPC transport for the
706 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
707 * server, for instance. It assumes that the caller has ensured that
708 * there are no active RPC tasks by using some form of locking.
709 *
710 * Returns zero if "clnt" is now using the new xprt. Otherwise a
711 * negative errno is returned, and "clnt" continues to use the old
712 * xprt.
713 */
714 int rpc_switch_client_transport(struct rpc_clnt *clnt,
715 struct xprt_create *args,
716 const struct rpc_timeout *timeout)
717 {
718 const struct rpc_timeout *old_timeo;
719 rpc_authflavor_t pseudoflavor;
720 struct rpc_xprt_switch *xps, *oldxps;
721 struct rpc_xprt *xprt, *old;
722 struct rpc_clnt *parent;
723 int err;
724
725 xprt = xprt_create_transport(args);
726 if (IS_ERR(xprt)) {
727 dprintk("RPC: failed to create new xprt for clnt %p\n",
728 clnt);
729 return PTR_ERR(xprt);
730 }
731
732 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
733 if (xps == NULL) {
734 xprt_put(xprt);
735 return -ENOMEM;
736 }
737
738 pseudoflavor = clnt->cl_auth->au_flavor;
739
740 old_timeo = clnt->cl_timeout;
741 old = rpc_clnt_set_transport(clnt, xprt, timeout);
742 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
743
744 rpc_unregister_client(clnt);
745 __rpc_clnt_remove_pipedir(clnt);
746 rpc_clnt_debugfs_unregister(clnt);
747
748 /*
749 * A new transport was created. "clnt" therefore
750 * becomes the root of a new cl_parent tree. clnt's
751 * children, if it has any, still point to the old xprt.
752 */
753 parent = clnt->cl_parent;
754 clnt->cl_parent = clnt;
755
756 /*
757 * The old rpc_auth cache cannot be re-used. GSS
758 * contexts in particular are between a single
759 * client and server.
760 */
761 err = rpc_client_register(clnt, pseudoflavor, NULL);
762 if (err)
763 goto out_revert;
764
765 synchronize_rcu();
766 if (parent != clnt)
767 rpc_release_client(parent);
768 xprt_switch_put(oldxps);
769 xprt_put(old);
770 dprintk("RPC: replaced xprt for clnt %p\n", clnt);
771 return 0;
772
773 out_revert:
774 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
775 rpc_clnt_set_transport(clnt, old, old_timeo);
776 clnt->cl_parent = parent;
777 rpc_client_register(clnt, pseudoflavor, NULL);
778 xprt_switch_put(xps);
779 xprt_put(xprt);
780 dprintk("RPC: failed to switch xprt for clnt %p\n", clnt);
781 return err;
782 }
783 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
784
785 static
786 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
787 {
788 struct rpc_xprt_switch *xps;
789
790 rcu_read_lock();
791 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
792 rcu_read_unlock();
793 if (xps == NULL)
794 return -EAGAIN;
795 xprt_iter_init_listall(xpi, xps);
796 xprt_switch_put(xps);
797 return 0;
798 }
799
800 /**
801 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
802 * @clnt: pointer to client
803 * @fn: function to apply
804 * @data: void pointer to function data
805 *
806 * Iterates through the list of RPC transports currently attached to the
807 * client and applies the function fn(clnt, xprt, data).
808 *
809 * On error, the iteration stops, and the function returns the error value.
810 */
811 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
812 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
813 void *data)
814 {
815 struct rpc_xprt_iter xpi;
816 int ret;
817
818 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
819 if (ret)
820 return ret;
821 for (;;) {
822 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
823
824 if (!xprt)
825 break;
826 ret = fn(clnt, xprt, data);
827 xprt_put(xprt);
828 if (ret < 0)
829 break;
830 }
831 xprt_iter_destroy(&xpi);
832 return ret;
833 }
834 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
835
836 /*
837 * Kill all tasks for the given client.
838 * XXX: kill their descendants as well?
839 */
840 void rpc_killall_tasks(struct rpc_clnt *clnt)
841 {
842 struct rpc_task *rovr;
843
844
845 if (list_empty(&clnt->cl_tasks))
846 return;
847 dprintk("RPC: killing all tasks for client %p\n", clnt);
848 /*
849 * Spin lock all_tasks to prevent changes...
850 */
851 spin_lock(&clnt->cl_lock);
852 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
853 rpc_signal_task(rovr);
854 spin_unlock(&clnt->cl_lock);
855 }
856 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
857
858 /*
859 * Properly shut down an RPC client, terminating all outstanding
860 * requests.
861 */
862 void rpc_shutdown_client(struct rpc_clnt *clnt)
863 {
864 might_sleep();
865
866 dprintk_rcu("RPC: shutting down %s client for %s\n",
867 clnt->cl_program->name,
868 rcu_dereference(clnt->cl_xprt)->servername);
869
870 while (!list_empty(&clnt->cl_tasks)) {
871 rpc_killall_tasks(clnt);
872 wait_event_timeout(destroy_wait,
873 list_empty(&clnt->cl_tasks), 1*HZ);
874 }
875
876 rpc_release_client(clnt);
877 }
878 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
879
880 /*
881 * Free an RPC client
882 */
883 static struct rpc_clnt *
884 rpc_free_client(struct rpc_clnt *clnt)
885 {
886 struct rpc_clnt *parent = NULL;
887
888 dprintk_rcu("RPC: destroying %s client for %s\n",
889 clnt->cl_program->name,
890 rcu_dereference(clnt->cl_xprt)->servername);
891 if (clnt->cl_parent != clnt)
892 parent = clnt->cl_parent;
893 rpc_clnt_debugfs_unregister(clnt);
894 rpc_clnt_remove_pipedir(clnt);
895 rpc_unregister_client(clnt);
896 rpc_free_iostats(clnt->cl_metrics);
897 clnt->cl_metrics = NULL;
898 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
899 xprt_iter_destroy(&clnt->cl_xpi);
900 rpciod_down();
901 put_cred(clnt->cl_cred);
902 rpc_free_clid(clnt);
903 kfree(clnt);
904 return parent;
905 }
906
907 /*
908 * Free an RPC client
909 */
910 static struct rpc_clnt *
911 rpc_free_auth(struct rpc_clnt *clnt)
912 {
913 if (clnt->cl_auth == NULL)
914 return rpc_free_client(clnt);
915
916 /*
917 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
918 * release remaining GSS contexts. This mechanism ensures
919 * that it can do so safely.
920 */
921 atomic_inc(&clnt->cl_count);
922 rpcauth_release(clnt->cl_auth);
923 clnt->cl_auth = NULL;
924 if (atomic_dec_and_test(&clnt->cl_count))
925 return rpc_free_client(clnt);
926 return NULL;
927 }
928
929 /*
930 * Release reference to the RPC client
931 */
932 void
933 rpc_release_client(struct rpc_clnt *clnt)
934 {
935 dprintk("RPC: rpc_release_client(%p)\n", 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 if (msg->rpc_cred != NULL)
1103 task->tk_msg.rpc_cred = get_cred(msg->rpc_cred);
1104 }
1105 }
1106
1107 /*
1108 * Default callback for async RPC calls
1109 */
1110 static void
1111 rpc_default_callback(struct rpc_task *task, void *data)
1112 {
1113 }
1114
1115 static const struct rpc_call_ops rpc_default_ops = {
1116 .rpc_call_done = rpc_default_callback,
1117 };
1118
1119 /**
1120 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1121 * @task_setup_data: pointer to task initialisation data
1122 */
1123 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1124 {
1125 struct rpc_task *task;
1126
1127 task = rpc_new_task(task_setup_data);
1128
1129 rpc_task_set_client(task, task_setup_data->rpc_client);
1130 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1131
1132 if (task->tk_action == NULL)
1133 rpc_call_start(task);
1134
1135 atomic_inc(&task->tk_count);
1136 rpc_execute(task);
1137 return task;
1138 }
1139 EXPORT_SYMBOL_GPL(rpc_run_task);
1140
1141 /**
1142 * rpc_call_sync - Perform a synchronous RPC call
1143 * @clnt: pointer to RPC client
1144 * @msg: RPC call parameters
1145 * @flags: RPC call flags
1146 */
1147 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1148 {
1149 struct rpc_task *task;
1150 struct rpc_task_setup task_setup_data = {
1151 .rpc_client = clnt,
1152 .rpc_message = msg,
1153 .callback_ops = &rpc_default_ops,
1154 .flags = flags,
1155 };
1156 int status;
1157
1158 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1159 if (flags & RPC_TASK_ASYNC) {
1160 rpc_release_calldata(task_setup_data.callback_ops,
1161 task_setup_data.callback_data);
1162 return -EINVAL;
1163 }
1164
1165 task = rpc_run_task(&task_setup_data);
1166 if (IS_ERR(task))
1167 return PTR_ERR(task);
1168 status = task->tk_status;
1169 rpc_put_task(task);
1170 return status;
1171 }
1172 EXPORT_SYMBOL_GPL(rpc_call_sync);
1173
1174 /**
1175 * rpc_call_async - Perform an asynchronous RPC call
1176 * @clnt: pointer to RPC client
1177 * @msg: RPC call parameters
1178 * @flags: RPC call flags
1179 * @tk_ops: RPC call ops
1180 * @data: user call data
1181 */
1182 int
1183 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1184 const struct rpc_call_ops *tk_ops, void *data)
1185 {
1186 struct rpc_task *task;
1187 struct rpc_task_setup task_setup_data = {
1188 .rpc_client = clnt,
1189 .rpc_message = msg,
1190 .callback_ops = tk_ops,
1191 .callback_data = data,
1192 .flags = flags|RPC_TASK_ASYNC,
1193 };
1194
1195 task = rpc_run_task(&task_setup_data);
1196 if (IS_ERR(task))
1197 return PTR_ERR(task);
1198 rpc_put_task(task);
1199 return 0;
1200 }
1201 EXPORT_SYMBOL_GPL(rpc_call_async);
1202
1203 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1204 static void call_bc_encode(struct rpc_task *task);
1205
1206 /**
1207 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1208 * rpc_execute against it
1209 * @req: RPC request
1210 */
1211 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req)
1212 {
1213 struct rpc_task *task;
1214 struct rpc_task_setup task_setup_data = {
1215 .callback_ops = &rpc_default_ops,
1216 .flags = RPC_TASK_SOFTCONN |
1217 RPC_TASK_NO_RETRANS_TIMEOUT,
1218 };
1219
1220 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1221 /*
1222 * Create an rpc_task to send the data
1223 */
1224 task = rpc_new_task(&task_setup_data);
1225 xprt_init_bc_request(req, task);
1226
1227 task->tk_action = call_bc_encode;
1228 atomic_inc(&task->tk_count);
1229 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1230 rpc_execute(task);
1231
1232 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1233 return task;
1234 }
1235 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1236
1237 /**
1238 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1239 * @req: RPC request to prepare
1240 * @pages: vector of struct page pointers
1241 * @base: offset in first page where receive should start, in bytes
1242 * @len: expected size of the upper layer data payload, in bytes
1243 * @hdrsize: expected size of upper layer reply header, in XDR words
1244 *
1245 */
1246 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1247 unsigned int base, unsigned int len,
1248 unsigned int hdrsize)
1249 {
1250 /* Subtract one to force an extra word of buffer space for the
1251 * payload's XDR pad to fall into the rcv_buf's tail iovec.
1252 */
1253 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign - 1;
1254
1255 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1256 trace_rpc_reply_pages(req);
1257 }
1258 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1259
1260 void
1261 rpc_call_start(struct rpc_task *task)
1262 {
1263 task->tk_action = call_start;
1264 }
1265 EXPORT_SYMBOL_GPL(rpc_call_start);
1266
1267 /**
1268 * rpc_peeraddr - extract remote peer address from clnt's xprt
1269 * @clnt: RPC client structure
1270 * @buf: target buffer
1271 * @bufsize: length of target buffer
1272 *
1273 * Returns the number of bytes that are actually in the stored address.
1274 */
1275 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1276 {
1277 size_t bytes;
1278 struct rpc_xprt *xprt;
1279
1280 rcu_read_lock();
1281 xprt = rcu_dereference(clnt->cl_xprt);
1282
1283 bytes = xprt->addrlen;
1284 if (bytes > bufsize)
1285 bytes = bufsize;
1286 memcpy(buf, &xprt->addr, bytes);
1287 rcu_read_unlock();
1288
1289 return bytes;
1290 }
1291 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1292
1293 /**
1294 * rpc_peeraddr2str - return remote peer address in printable format
1295 * @clnt: RPC client structure
1296 * @format: address format
1297 *
1298 * NB: the lifetime of the memory referenced by the returned pointer is
1299 * the same as the rpc_xprt itself. As long as the caller uses this
1300 * pointer, it must hold the RCU read lock.
1301 */
1302 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1303 enum rpc_display_format_t format)
1304 {
1305 struct rpc_xprt *xprt;
1306
1307 xprt = rcu_dereference(clnt->cl_xprt);
1308
1309 if (xprt->address_strings[format] != NULL)
1310 return xprt->address_strings[format];
1311 else
1312 return "unprintable";
1313 }
1314 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1315
1316 static const struct sockaddr_in rpc_inaddr_loopback = {
1317 .sin_family = AF_INET,
1318 .sin_addr.s_addr = htonl(INADDR_ANY),
1319 };
1320
1321 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1322 .sin6_family = AF_INET6,
1323 .sin6_addr = IN6ADDR_ANY_INIT,
1324 };
1325
1326 /*
1327 * Try a getsockname() on a connected datagram socket. Using a
1328 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1329 * This conserves the ephemeral port number space.
1330 *
1331 * Returns zero and fills in "buf" if successful; otherwise, a
1332 * negative errno is returned.
1333 */
1334 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1335 struct sockaddr *buf)
1336 {
1337 struct socket *sock;
1338 int err;
1339
1340 err = __sock_create(net, sap->sa_family,
1341 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1342 if (err < 0) {
1343 dprintk("RPC: can't create UDP socket (%d)\n", err);
1344 goto out;
1345 }
1346
1347 switch (sap->sa_family) {
1348 case AF_INET:
1349 err = kernel_bind(sock,
1350 (struct sockaddr *)&rpc_inaddr_loopback,
1351 sizeof(rpc_inaddr_loopback));
1352 break;
1353 case AF_INET6:
1354 err = kernel_bind(sock,
1355 (struct sockaddr *)&rpc_in6addr_loopback,
1356 sizeof(rpc_in6addr_loopback));
1357 break;
1358 default:
1359 err = -EAFNOSUPPORT;
1360 goto out;
1361 }
1362 if (err < 0) {
1363 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1364 goto out_release;
1365 }
1366
1367 err = kernel_connect(sock, sap, salen, 0);
1368 if (err < 0) {
1369 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1370 goto out_release;
1371 }
1372
1373 err = kernel_getsockname(sock, buf);
1374 if (err < 0) {
1375 dprintk("RPC: getsockname failed (%d)\n", err);
1376 goto out_release;
1377 }
1378
1379 err = 0;
1380 if (buf->sa_family == AF_INET6) {
1381 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1382 sin6->sin6_scope_id = 0;
1383 }
1384 dprintk("RPC: %s succeeded\n", __func__);
1385
1386 out_release:
1387 sock_release(sock);
1388 out:
1389 return err;
1390 }
1391
1392 /*
1393 * Scraping a connected socket failed, so we don't have a useable
1394 * local address. Fallback: generate an address that will prevent
1395 * the server from calling us back.
1396 *
1397 * Returns zero and fills in "buf" if successful; otherwise, a
1398 * negative errno is returned.
1399 */
1400 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1401 {
1402 switch (family) {
1403 case AF_INET:
1404 if (buflen < sizeof(rpc_inaddr_loopback))
1405 return -EINVAL;
1406 memcpy(buf, &rpc_inaddr_loopback,
1407 sizeof(rpc_inaddr_loopback));
1408 break;
1409 case AF_INET6:
1410 if (buflen < sizeof(rpc_in6addr_loopback))
1411 return -EINVAL;
1412 memcpy(buf, &rpc_in6addr_loopback,
1413 sizeof(rpc_in6addr_loopback));
1414 break;
1415 default:
1416 dprintk("RPC: %s: address family not supported\n",
1417 __func__);
1418 return -EAFNOSUPPORT;
1419 }
1420 dprintk("RPC: %s: succeeded\n", __func__);
1421 return 0;
1422 }
1423
1424 /**
1425 * rpc_localaddr - discover local endpoint address for an RPC client
1426 * @clnt: RPC client structure
1427 * @buf: target buffer
1428 * @buflen: size of target buffer, in bytes
1429 *
1430 * Returns zero and fills in "buf" and "buflen" if successful;
1431 * otherwise, a negative errno is returned.
1432 *
1433 * This works even if the underlying transport is not currently connected,
1434 * or if the upper layer never previously provided a source address.
1435 *
1436 * The result of this function call is transient: multiple calls in
1437 * succession may give different results, depending on how local
1438 * networking configuration changes over time.
1439 */
1440 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1441 {
1442 struct sockaddr_storage address;
1443 struct sockaddr *sap = (struct sockaddr *)&address;
1444 struct rpc_xprt *xprt;
1445 struct net *net;
1446 size_t salen;
1447 int err;
1448
1449 rcu_read_lock();
1450 xprt = rcu_dereference(clnt->cl_xprt);
1451 salen = xprt->addrlen;
1452 memcpy(sap, &xprt->addr, salen);
1453 net = get_net(xprt->xprt_net);
1454 rcu_read_unlock();
1455
1456 rpc_set_port(sap, 0);
1457 err = rpc_sockname(net, sap, salen, buf);
1458 put_net(net);
1459 if (err != 0)
1460 /* Couldn't discover local address, return ANYADDR */
1461 return rpc_anyaddr(sap->sa_family, buf, buflen);
1462 return 0;
1463 }
1464 EXPORT_SYMBOL_GPL(rpc_localaddr);
1465
1466 void
1467 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1468 {
1469 struct rpc_xprt *xprt;
1470
1471 rcu_read_lock();
1472 xprt = rcu_dereference(clnt->cl_xprt);
1473 if (xprt->ops->set_buffer_size)
1474 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1475 rcu_read_unlock();
1476 }
1477 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1478
1479 /**
1480 * rpc_net_ns - Get the network namespace for this RPC client
1481 * @clnt: RPC client to query
1482 *
1483 */
1484 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1485 {
1486 struct net *ret;
1487
1488 rcu_read_lock();
1489 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1490 rcu_read_unlock();
1491 return ret;
1492 }
1493 EXPORT_SYMBOL_GPL(rpc_net_ns);
1494
1495 /**
1496 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1497 * @clnt: RPC client to query
1498 *
1499 * For stream transports, this is one RPC record fragment (see RFC
1500 * 1831), as we don't support multi-record requests yet. For datagram
1501 * transports, this is the size of an IP packet minus the IP, UDP, and
1502 * RPC header sizes.
1503 */
1504 size_t rpc_max_payload(struct rpc_clnt *clnt)
1505 {
1506 size_t ret;
1507
1508 rcu_read_lock();
1509 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1510 rcu_read_unlock();
1511 return ret;
1512 }
1513 EXPORT_SYMBOL_GPL(rpc_max_payload);
1514
1515 /**
1516 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1517 * @clnt: RPC client to query
1518 */
1519 size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1520 {
1521 struct rpc_xprt *xprt;
1522 size_t ret;
1523
1524 rcu_read_lock();
1525 xprt = rcu_dereference(clnt->cl_xprt);
1526 ret = xprt->ops->bc_maxpayload(xprt);
1527 rcu_read_unlock();
1528 return ret;
1529 }
1530 EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1531
1532 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1533 {
1534 struct rpc_xprt *xprt;
1535 unsigned int ret;
1536
1537 rcu_read_lock();
1538 xprt = rcu_dereference(clnt->cl_xprt);
1539 ret = xprt->ops->bc_num_slots(xprt);
1540 rcu_read_unlock();
1541 return ret;
1542 }
1543 EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1544
1545 /**
1546 * rpc_force_rebind - force transport to check that remote port is unchanged
1547 * @clnt: client to rebind
1548 *
1549 */
1550 void rpc_force_rebind(struct rpc_clnt *clnt)
1551 {
1552 if (clnt->cl_autobind) {
1553 rcu_read_lock();
1554 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1555 rcu_read_unlock();
1556 }
1557 }
1558 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1559
1560 static int
1561 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1562 {
1563 task->tk_status = 0;
1564 task->tk_rpc_status = 0;
1565 task->tk_action = action;
1566 return 1;
1567 }
1568
1569 /*
1570 * Restart an (async) RPC call. Usually called from within the
1571 * exit handler.
1572 */
1573 int
1574 rpc_restart_call(struct rpc_task *task)
1575 {
1576 return __rpc_restart_call(task, call_start);
1577 }
1578 EXPORT_SYMBOL_GPL(rpc_restart_call);
1579
1580 /*
1581 * Restart an (async) RPC call from the call_prepare state.
1582 * Usually called from within the exit handler.
1583 */
1584 int
1585 rpc_restart_call_prepare(struct rpc_task *task)
1586 {
1587 if (task->tk_ops->rpc_call_prepare != NULL)
1588 return __rpc_restart_call(task, rpc_prepare_task);
1589 return rpc_restart_call(task);
1590 }
1591 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1592
1593 const char
1594 *rpc_proc_name(const struct rpc_task *task)
1595 {
1596 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1597
1598 if (proc) {
1599 if (proc->p_name)
1600 return proc->p_name;
1601 else
1602 return "NULL";
1603 } else
1604 return "no proc";
1605 }
1606
1607 static void
1608 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1609 {
1610 task->tk_rpc_status = rpc_status;
1611 rpc_exit(task, tk_status);
1612 }
1613
1614 static void
1615 rpc_call_rpcerror(struct rpc_task *task, int status)
1616 {
1617 __rpc_call_rpcerror(task, status, status);
1618 }
1619
1620 /*
1621 * 0. Initial state
1622 *
1623 * Other FSM states can be visited zero or more times, but
1624 * this state is visited exactly once for each RPC.
1625 */
1626 static void
1627 call_start(struct rpc_task *task)
1628 {
1629 struct rpc_clnt *clnt = task->tk_client;
1630 int idx = task->tk_msg.rpc_proc->p_statidx;
1631
1632 trace_rpc_request(task);
1633 dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
1634 clnt->cl_program->name, clnt->cl_vers,
1635 rpc_proc_name(task),
1636 (RPC_IS_ASYNC(task) ? "async" : "sync"));
1637
1638 /* Increment call count (version might not be valid for ping) */
1639 if (clnt->cl_program->version[clnt->cl_vers])
1640 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1641 clnt->cl_stats->rpccnt++;
1642 task->tk_action = call_reserve;
1643 rpc_task_set_transport(task, clnt);
1644 }
1645
1646 /*
1647 * 1. Reserve an RPC call slot
1648 */
1649 static void
1650 call_reserve(struct rpc_task *task)
1651 {
1652 dprint_status(task);
1653
1654 task->tk_status = 0;
1655 task->tk_action = call_reserveresult;
1656 xprt_reserve(task);
1657 }
1658
1659 static void call_retry_reserve(struct rpc_task *task);
1660
1661 /*
1662 * 1b. Grok the result of xprt_reserve()
1663 */
1664 static void
1665 call_reserveresult(struct rpc_task *task)
1666 {
1667 int status = task->tk_status;
1668
1669 dprint_status(task);
1670
1671 /*
1672 * After a call to xprt_reserve(), we must have either
1673 * a request slot or else an error status.
1674 */
1675 task->tk_status = 0;
1676 if (status >= 0) {
1677 if (task->tk_rqstp) {
1678 task->tk_action = call_refresh;
1679 return;
1680 }
1681
1682 rpc_call_rpcerror(task, -EIO);
1683 return;
1684 }
1685
1686 /*
1687 * Even though there was an error, we may have acquired
1688 * a request slot somehow. Make sure not to leak it.
1689 */
1690 if (task->tk_rqstp)
1691 xprt_release(task);
1692
1693 switch (status) {
1694 case -ENOMEM:
1695 rpc_delay(task, HZ >> 2);
1696 /* fall through */
1697 case -EAGAIN: /* woken up; retry */
1698 task->tk_action = call_retry_reserve;
1699 return;
1700 default:
1701 rpc_call_rpcerror(task, status);
1702 }
1703 }
1704
1705 /*
1706 * 1c. Retry reserving an RPC call slot
1707 */
1708 static void
1709 call_retry_reserve(struct rpc_task *task)
1710 {
1711 dprint_status(task);
1712
1713 task->tk_status = 0;
1714 task->tk_action = call_reserveresult;
1715 xprt_retry_reserve(task);
1716 }
1717
1718 /*
1719 * 2. Bind and/or refresh the credentials
1720 */
1721 static void
1722 call_refresh(struct rpc_task *task)
1723 {
1724 dprint_status(task);
1725
1726 task->tk_action = call_refreshresult;
1727 task->tk_status = 0;
1728 task->tk_client->cl_stats->rpcauthrefresh++;
1729 rpcauth_refreshcred(task);
1730 }
1731
1732 /*
1733 * 2a. Process the results of a credential refresh
1734 */
1735 static void
1736 call_refreshresult(struct rpc_task *task)
1737 {
1738 int status = task->tk_status;
1739
1740 dprint_status(task);
1741
1742 task->tk_status = 0;
1743 task->tk_action = call_refresh;
1744 switch (status) {
1745 case 0:
1746 if (rpcauth_uptodatecred(task)) {
1747 task->tk_action = call_allocate;
1748 return;
1749 }
1750 /* Use rate-limiting and a max number of retries if refresh
1751 * had status 0 but failed to update the cred.
1752 */
1753 /* fall through */
1754 case -ETIMEDOUT:
1755 rpc_delay(task, 3*HZ);
1756 /* fall through */
1757 case -EAGAIN:
1758 status = -EACCES;
1759 /* fall through */
1760 case -EKEYEXPIRED:
1761 if (!task->tk_cred_retry)
1762 break;
1763 task->tk_cred_retry--;
1764 dprintk("RPC: %5u %s: retry refresh creds\n",
1765 task->tk_pid, __func__);
1766 return;
1767 }
1768 dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
1769 task->tk_pid, __func__, status);
1770 rpc_call_rpcerror(task, status);
1771 }
1772
1773 /*
1774 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1775 * (Note: buffer memory is freed in xprt_release).
1776 */
1777 static void
1778 call_allocate(struct rpc_task *task)
1779 {
1780 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1781 struct rpc_rqst *req = task->tk_rqstp;
1782 struct rpc_xprt *xprt = req->rq_xprt;
1783 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1784 int status;
1785
1786 dprint_status(task);
1787
1788 task->tk_status = 0;
1789 task->tk_action = call_encode;
1790
1791 if (req->rq_buffer)
1792 return;
1793
1794 if (proc->p_proc != 0) {
1795 BUG_ON(proc->p_arglen == 0);
1796 if (proc->p_decode != NULL)
1797 BUG_ON(proc->p_replen == 0);
1798 }
1799
1800 /*
1801 * Calculate the size (in quads) of the RPC call
1802 * and reply headers, and convert both values
1803 * to byte sizes.
1804 */
1805 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1806 proc->p_arglen;
1807 req->rq_callsize <<= 2;
1808 /*
1809 * Note: the reply buffer must at minimum allocate enough space
1810 * for the 'struct accepted_reply' from RFC5531.
1811 */
1812 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1813 max_t(size_t, proc->p_replen, 2);
1814 req->rq_rcvsize <<= 2;
1815
1816 status = xprt->ops->buf_alloc(task);
1817 xprt_inject_disconnect(xprt);
1818 if (status == 0)
1819 return;
1820 if (status != -ENOMEM) {
1821 rpc_call_rpcerror(task, status);
1822 return;
1823 }
1824
1825 dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
1826
1827 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1828 task->tk_action = call_allocate;
1829 rpc_delay(task, HZ>>4);
1830 return;
1831 }
1832
1833 rpc_call_rpcerror(task, -ERESTARTSYS);
1834 }
1835
1836 static int
1837 rpc_task_need_encode(struct rpc_task *task)
1838 {
1839 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1840 (!(task->tk_flags & RPC_TASK_SENT) ||
1841 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1842 xprt_request_need_retransmit(task));
1843 }
1844
1845 static void
1846 rpc_xdr_encode(struct rpc_task *task)
1847 {
1848 struct rpc_rqst *req = task->tk_rqstp;
1849 struct xdr_stream xdr;
1850
1851 xdr_buf_init(&req->rq_snd_buf,
1852 req->rq_buffer,
1853 req->rq_callsize);
1854 xdr_buf_init(&req->rq_rcv_buf,
1855 req->rq_rbuffer,
1856 req->rq_rcvsize);
1857
1858 req->rq_reply_bytes_recvd = 0;
1859 req->rq_snd_buf.head[0].iov_len = 0;
1860 xdr_init_encode(&xdr, &req->rq_snd_buf,
1861 req->rq_snd_buf.head[0].iov_base, req);
1862 xdr_free_bvec(&req->rq_snd_buf);
1863 if (rpc_encode_header(task, &xdr))
1864 return;
1865
1866 task->tk_status = rpcauth_wrap_req(task, &xdr);
1867 }
1868
1869 /*
1870 * 3. Encode arguments of an RPC call
1871 */
1872 static void
1873 call_encode(struct rpc_task *task)
1874 {
1875 if (!rpc_task_need_encode(task))
1876 goto out;
1877 dprint_status(task);
1878 /* Dequeue task from the receive queue while we're encoding */
1879 xprt_request_dequeue_xprt(task);
1880 /* Encode here so that rpcsec_gss can use correct sequence number. */
1881 rpc_xdr_encode(task);
1882 /* Did the encode result in an error condition? */
1883 if (task->tk_status != 0) {
1884 /* Was the error nonfatal? */
1885 switch (task->tk_status) {
1886 case -EAGAIN:
1887 case -ENOMEM:
1888 rpc_delay(task, HZ >> 4);
1889 break;
1890 case -EKEYEXPIRED:
1891 if (!task->tk_cred_retry) {
1892 rpc_exit(task, task->tk_status);
1893 } else {
1894 task->tk_action = call_refresh;
1895 task->tk_cred_retry--;
1896 dprintk("RPC: %5u %s: retry refresh creds\n",
1897 task->tk_pid, __func__);
1898 }
1899 break;
1900 default:
1901 rpc_call_rpcerror(task, task->tk_status);
1902 }
1903 return;
1904 }
1905
1906 /* Add task to reply queue before transmission to avoid races */
1907 if (rpc_reply_expected(task))
1908 xprt_request_enqueue_receive(task);
1909 xprt_request_enqueue_transmit(task);
1910 out:
1911 task->tk_action = call_transmit;
1912 /* Check that the connection is OK */
1913 if (!xprt_bound(task->tk_xprt))
1914 task->tk_action = call_bind;
1915 else if (!xprt_connected(task->tk_xprt))
1916 task->tk_action = call_connect;
1917 }
1918
1919 /*
1920 * Helpers to check if the task was already transmitted, and
1921 * to take action when that is the case.
1922 */
1923 static bool
1924 rpc_task_transmitted(struct rpc_task *task)
1925 {
1926 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
1927 }
1928
1929 static void
1930 rpc_task_handle_transmitted(struct rpc_task *task)
1931 {
1932 xprt_end_transmit(task);
1933 task->tk_action = call_transmit_status;
1934 }
1935
1936 /*
1937 * 4. Get the server port number if not yet set
1938 */
1939 static void
1940 call_bind(struct rpc_task *task)
1941 {
1942 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1943
1944 if (rpc_task_transmitted(task)) {
1945 rpc_task_handle_transmitted(task);
1946 return;
1947 }
1948
1949 if (xprt_bound(xprt)) {
1950 task->tk_action = call_connect;
1951 return;
1952 }
1953
1954 dprint_status(task);
1955
1956 task->tk_action = call_bind_status;
1957 if (!xprt_prepare_transmit(task))
1958 return;
1959
1960 xprt->ops->rpcbind(task);
1961 }
1962
1963 /*
1964 * 4a. Sort out bind result
1965 */
1966 static void
1967 call_bind_status(struct rpc_task *task)
1968 {
1969 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
1970 int status = -EIO;
1971
1972 if (rpc_task_transmitted(task)) {
1973 rpc_task_handle_transmitted(task);
1974 return;
1975 }
1976
1977 dprint_status(task);
1978 trace_rpc_bind_status(task);
1979 if (task->tk_status >= 0)
1980 goto out_next;
1981 if (xprt_bound(xprt)) {
1982 task->tk_status = 0;
1983 goto out_next;
1984 }
1985
1986 switch (task->tk_status) {
1987 case -ENOMEM:
1988 dprintk("RPC: %5u rpcbind out of memory\n", task->tk_pid);
1989 rpc_delay(task, HZ >> 2);
1990 goto retry_timeout;
1991 case -EACCES:
1992 dprintk("RPC: %5u remote rpcbind: RPC program/version "
1993 "unavailable\n", task->tk_pid);
1994 /* fail immediately if this is an RPC ping */
1995 if (task->tk_msg.rpc_proc->p_proc == 0) {
1996 status = -EOPNOTSUPP;
1997 break;
1998 }
1999 if (task->tk_rebind_retry == 0)
2000 break;
2001 task->tk_rebind_retry--;
2002 rpc_delay(task, 3*HZ);
2003 goto retry_timeout;
2004 case -ENOBUFS:
2005 rpc_delay(task, HZ >> 2);
2006 goto retry_timeout;
2007 case -EAGAIN:
2008 goto retry_timeout;
2009 case -ETIMEDOUT:
2010 dprintk("RPC: %5u rpcbind request timed out\n",
2011 task->tk_pid);
2012 goto retry_timeout;
2013 case -EPFNOSUPPORT:
2014 /* server doesn't support any rpcbind version we know of */
2015 dprintk("RPC: %5u unrecognized remote rpcbind service\n",
2016 task->tk_pid);
2017 break;
2018 case -EPROTONOSUPPORT:
2019 dprintk("RPC: %5u remote rpcbind version unavailable, retrying\n",
2020 task->tk_pid);
2021 goto retry_timeout;
2022 case -ECONNREFUSED: /* connection problems */
2023 case -ECONNRESET:
2024 case -ECONNABORTED:
2025 case -ENOTCONN:
2026 case -EHOSTDOWN:
2027 case -ENETDOWN:
2028 case -EHOSTUNREACH:
2029 case -ENETUNREACH:
2030 case -EPIPE:
2031 dprintk("RPC: %5u remote rpcbind unreachable: %d\n",
2032 task->tk_pid, task->tk_status);
2033 if (!RPC_IS_SOFTCONN(task)) {
2034 rpc_delay(task, 5*HZ);
2035 goto retry_timeout;
2036 }
2037 status = task->tk_status;
2038 break;
2039 default:
2040 dprintk("RPC: %5u unrecognized rpcbind error (%d)\n",
2041 task->tk_pid, -task->tk_status);
2042 }
2043
2044 rpc_call_rpcerror(task, status);
2045 return;
2046 out_next:
2047 task->tk_action = call_connect;
2048 return;
2049 retry_timeout:
2050 task->tk_status = 0;
2051 task->tk_action = call_bind;
2052 rpc_check_timeout(task);
2053 }
2054
2055 /*
2056 * 4b. Connect to the RPC server
2057 */
2058 static void
2059 call_connect(struct rpc_task *task)
2060 {
2061 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2062
2063 if (rpc_task_transmitted(task)) {
2064 rpc_task_handle_transmitted(task);
2065 return;
2066 }
2067
2068 if (xprt_connected(xprt)) {
2069 task->tk_action = call_transmit;
2070 return;
2071 }
2072
2073 dprintk("RPC: %5u call_connect xprt %p %s connected\n",
2074 task->tk_pid, xprt,
2075 (xprt_connected(xprt) ? "is" : "is not"));
2076
2077 task->tk_action = call_connect_status;
2078 if (task->tk_status < 0)
2079 return;
2080 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2081 rpc_call_rpcerror(task, -ENOTCONN);
2082 return;
2083 }
2084 if (!xprt_prepare_transmit(task))
2085 return;
2086 xprt_connect(task);
2087 }
2088
2089 /*
2090 * 4c. Sort out connect result
2091 */
2092 static void
2093 call_connect_status(struct rpc_task *task)
2094 {
2095 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2096 struct rpc_clnt *clnt = task->tk_client;
2097 int status = task->tk_status;
2098
2099 if (rpc_task_transmitted(task)) {
2100 rpc_task_handle_transmitted(task);
2101 return;
2102 }
2103
2104 dprint_status(task);
2105 trace_rpc_connect_status(task);
2106
2107 if (task->tk_status == 0) {
2108 clnt->cl_stats->netreconn++;
2109 goto out_next;
2110 }
2111 if (xprt_connected(xprt)) {
2112 task->tk_status = 0;
2113 goto out_next;
2114 }
2115
2116 task->tk_status = 0;
2117 switch (status) {
2118 case -ECONNREFUSED:
2119 /* A positive refusal suggests a rebind is needed. */
2120 if (RPC_IS_SOFTCONN(task))
2121 break;
2122 if (clnt->cl_autobind) {
2123 rpc_force_rebind(clnt);
2124 goto out_retry;
2125 }
2126 /* fall through */
2127 case -ECONNRESET:
2128 case -ECONNABORTED:
2129 case -ENETDOWN:
2130 case -ENETUNREACH:
2131 case -EHOSTUNREACH:
2132 case -EPIPE:
2133 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2134 task->tk_rqstp->rq_connect_cookie);
2135 if (RPC_IS_SOFTCONN(task))
2136 break;
2137 /* retry with existing socket, after a delay */
2138 rpc_delay(task, 3*HZ);
2139 /* fall through */
2140 case -EADDRINUSE:
2141 case -ENOTCONN:
2142 case -EAGAIN:
2143 case -ETIMEDOUT:
2144 goto out_retry;
2145 case -ENOBUFS:
2146 rpc_delay(task, HZ >> 2);
2147 goto out_retry;
2148 }
2149 rpc_call_rpcerror(task, status);
2150 return;
2151 out_next:
2152 task->tk_action = call_transmit;
2153 return;
2154 out_retry:
2155 /* Check for timeouts before looping back to call_bind */
2156 task->tk_action = call_bind;
2157 rpc_check_timeout(task);
2158 }
2159
2160 /*
2161 * 5. Transmit the RPC request, and wait for reply
2162 */
2163 static void
2164 call_transmit(struct rpc_task *task)
2165 {
2166 if (rpc_task_transmitted(task)) {
2167 rpc_task_handle_transmitted(task);
2168 return;
2169 }
2170
2171 dprint_status(task);
2172
2173 task->tk_action = call_transmit_status;
2174 if (!xprt_prepare_transmit(task))
2175 return;
2176 task->tk_status = 0;
2177 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2178 if (!xprt_connected(task->tk_xprt)) {
2179 task->tk_status = -ENOTCONN;
2180 return;
2181 }
2182 xprt_transmit(task);
2183 }
2184 xprt_end_transmit(task);
2185 }
2186
2187 /*
2188 * 5a. Handle cleanup after a transmission
2189 */
2190 static void
2191 call_transmit_status(struct rpc_task *task)
2192 {
2193 task->tk_action = call_status;
2194
2195 /*
2196 * Common case: success. Force the compiler to put this
2197 * test first.
2198 */
2199 if (rpc_task_transmitted(task)) {
2200 task->tk_status = 0;
2201 xprt_request_wait_receive(task);
2202 return;
2203 }
2204
2205 switch (task->tk_status) {
2206 default:
2207 dprint_status(task);
2208 break;
2209 case -EBADMSG:
2210 task->tk_status = 0;
2211 task->tk_action = call_encode;
2212 break;
2213 /*
2214 * Special cases: if we've been waiting on the
2215 * socket's write_space() callback, or if the
2216 * socket just returned a connection error,
2217 * then hold onto the transport lock.
2218 */
2219 case -ENOBUFS:
2220 rpc_delay(task, HZ>>2);
2221 /* fall through */
2222 case -EBADSLT:
2223 case -EAGAIN:
2224 task->tk_action = call_transmit;
2225 task->tk_status = 0;
2226 break;
2227 case -ECONNREFUSED:
2228 case -EHOSTDOWN:
2229 case -ENETDOWN:
2230 case -EHOSTUNREACH:
2231 case -ENETUNREACH:
2232 case -EPERM:
2233 if (RPC_IS_SOFTCONN(task)) {
2234 if (!task->tk_msg.rpc_proc->p_proc)
2235 trace_xprt_ping(task->tk_xprt,
2236 task->tk_status);
2237 rpc_call_rpcerror(task, task->tk_status);
2238 return;
2239 }
2240 /* fall through */
2241 case -ECONNRESET:
2242 case -ECONNABORTED:
2243 case -EADDRINUSE:
2244 case -ENOTCONN:
2245 case -EPIPE:
2246 task->tk_action = call_bind;
2247 task->tk_status = 0;
2248 break;
2249 }
2250 rpc_check_timeout(task);
2251 }
2252
2253 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
2254 static void call_bc_transmit(struct rpc_task *task);
2255 static void call_bc_transmit_status(struct rpc_task *task);
2256
2257 static void
2258 call_bc_encode(struct rpc_task *task)
2259 {
2260 xprt_request_enqueue_transmit(task);
2261 task->tk_action = call_bc_transmit;
2262 }
2263
2264 /*
2265 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2266 * addition, disconnect on connectivity errors.
2267 */
2268 static void
2269 call_bc_transmit(struct rpc_task *task)
2270 {
2271 task->tk_action = call_bc_transmit_status;
2272 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2273 if (!xprt_prepare_transmit(task))
2274 return;
2275 task->tk_status = 0;
2276 xprt_transmit(task);
2277 }
2278 xprt_end_transmit(task);
2279 }
2280
2281 static void
2282 call_bc_transmit_status(struct rpc_task *task)
2283 {
2284 struct rpc_rqst *req = task->tk_rqstp;
2285
2286 if (rpc_task_transmitted(task))
2287 task->tk_status = 0;
2288
2289 dprint_status(task);
2290
2291 switch (task->tk_status) {
2292 case 0:
2293 /* Success */
2294 case -ENETDOWN:
2295 case -EHOSTDOWN:
2296 case -EHOSTUNREACH:
2297 case -ENETUNREACH:
2298 case -ECONNRESET:
2299 case -ECONNREFUSED:
2300 case -EADDRINUSE:
2301 case -ENOTCONN:
2302 case -EPIPE:
2303 break;
2304 case -ENOBUFS:
2305 rpc_delay(task, HZ>>2);
2306 /* fall through */
2307 case -EBADSLT:
2308 case -EAGAIN:
2309 task->tk_status = 0;
2310 task->tk_action = call_bc_transmit;
2311 return;
2312 case -ETIMEDOUT:
2313 /*
2314 * Problem reaching the server. Disconnect and let the
2315 * forechannel reestablish the connection. The server will
2316 * have to retransmit the backchannel request and we'll
2317 * reprocess it. Since these ops are idempotent, there's no
2318 * need to cache our reply at this time.
2319 */
2320 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2321 "error: %d\n", task->tk_status);
2322 xprt_conditional_disconnect(req->rq_xprt,
2323 req->rq_connect_cookie);
2324 break;
2325 default:
2326 /*
2327 * We were unable to reply and will have to drop the
2328 * request. The server should reconnect and retransmit.
2329 */
2330 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2331 "error: %d\n", task->tk_status);
2332 break;
2333 }
2334 task->tk_action = rpc_exit_task;
2335 }
2336 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2337
2338 /*
2339 * 6. Sort out the RPC call status
2340 */
2341 static void
2342 call_status(struct rpc_task *task)
2343 {
2344 struct rpc_clnt *clnt = task->tk_client;
2345 int status;
2346
2347 if (!task->tk_msg.rpc_proc->p_proc)
2348 trace_xprt_ping(task->tk_xprt, task->tk_status);
2349
2350 dprint_status(task);
2351
2352 status = task->tk_status;
2353 if (status >= 0) {
2354 task->tk_action = call_decode;
2355 return;
2356 }
2357
2358 trace_rpc_call_status(task);
2359 task->tk_status = 0;
2360 switch(status) {
2361 case -EHOSTDOWN:
2362 case -ENETDOWN:
2363 case -EHOSTUNREACH:
2364 case -ENETUNREACH:
2365 case -EPERM:
2366 if (RPC_IS_SOFTCONN(task))
2367 goto out_exit;
2368 /*
2369 * Delay any retries for 3 seconds, then handle as if it
2370 * were a timeout.
2371 */
2372 rpc_delay(task, 3*HZ);
2373 /* fall through */
2374 case -ETIMEDOUT:
2375 break;
2376 case -ECONNREFUSED:
2377 case -ECONNRESET:
2378 case -ECONNABORTED:
2379 case -ENOTCONN:
2380 rpc_force_rebind(clnt);
2381 break;
2382 case -EADDRINUSE:
2383 rpc_delay(task, 3*HZ);
2384 /* fall through */
2385 case -EPIPE:
2386 case -EAGAIN:
2387 break;
2388 case -EIO:
2389 /* shutdown or soft timeout */
2390 goto out_exit;
2391 default:
2392 if (clnt->cl_chatty)
2393 printk("%s: RPC call returned error %d\n",
2394 clnt->cl_program->name, -status);
2395 goto out_exit;
2396 }
2397 task->tk_action = call_encode;
2398 rpc_check_timeout(task);
2399 return;
2400 out_exit:
2401 rpc_call_rpcerror(task, status);
2402 }
2403
2404 static bool
2405 rpc_check_connected(const struct rpc_rqst *req)
2406 {
2407 /* No allocated request or transport? return true */
2408 if (!req || !req->rq_xprt)
2409 return true;
2410 return xprt_connected(req->rq_xprt);
2411 }
2412
2413 static void
2414 rpc_check_timeout(struct rpc_task *task)
2415 {
2416 struct rpc_clnt *clnt = task->tk_client;
2417
2418 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2419 return;
2420
2421 dprintk("RPC: %5u call_timeout (major)\n", task->tk_pid);
2422 task->tk_timeouts++;
2423
2424 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2425 rpc_call_rpcerror(task, -ETIMEDOUT);
2426 return;
2427 }
2428
2429 if (RPC_IS_SOFT(task)) {
2430 /*
2431 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2432 * been sent, it should time out only if the transport
2433 * connection gets terminally broken.
2434 */
2435 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2436 rpc_check_connected(task->tk_rqstp))
2437 return;
2438
2439 if (clnt->cl_chatty) {
2440 pr_notice_ratelimited(
2441 "%s: server %s not responding, timed out\n",
2442 clnt->cl_program->name,
2443 task->tk_xprt->servername);
2444 }
2445 if (task->tk_flags & RPC_TASK_TIMEOUT)
2446 rpc_call_rpcerror(task, -ETIMEDOUT);
2447 else
2448 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2449 return;
2450 }
2451
2452 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2453 task->tk_flags |= RPC_CALL_MAJORSEEN;
2454 if (clnt->cl_chatty) {
2455 pr_notice_ratelimited(
2456 "%s: server %s not responding, still trying\n",
2457 clnt->cl_program->name,
2458 task->tk_xprt->servername);
2459 }
2460 }
2461 rpc_force_rebind(clnt);
2462 /*
2463 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2464 * event? RFC2203 requires the server to drop all such requests.
2465 */
2466 rpcauth_invalcred(task);
2467 }
2468
2469 /*
2470 * 7. Decode the RPC reply
2471 */
2472 static void
2473 call_decode(struct rpc_task *task)
2474 {
2475 struct rpc_clnt *clnt = task->tk_client;
2476 struct rpc_rqst *req = task->tk_rqstp;
2477 struct xdr_stream xdr;
2478 int err;
2479
2480 dprint_status(task);
2481
2482 if (!task->tk_msg.rpc_proc->p_decode) {
2483 task->tk_action = rpc_exit_task;
2484 return;
2485 }
2486
2487 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2488 if (clnt->cl_chatty) {
2489 pr_notice_ratelimited("%s: server %s OK\n",
2490 clnt->cl_program->name,
2491 task->tk_xprt->servername);
2492 }
2493 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2494 }
2495
2496 /*
2497 * Ensure that we see all writes made by xprt_complete_rqst()
2498 * before it changed req->rq_reply_bytes_recvd.
2499 */
2500 smp_rmb();
2501
2502 /*
2503 * Did we ever call xprt_complete_rqst()? If not, we should assume
2504 * the message is incomplete.
2505 */
2506 err = -EAGAIN;
2507 if (!req->rq_reply_bytes_recvd)
2508 goto out;
2509
2510 req->rq_rcv_buf.len = req->rq_private_buf.len;
2511
2512 /* Check that the softirq receive buffer is valid */
2513 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2514 sizeof(req->rq_rcv_buf)) != 0);
2515
2516 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2517 req->rq_rcv_buf.head[0].iov_base, req);
2518 err = rpc_decode_header(task, &xdr);
2519 out:
2520 switch (err) {
2521 case 0:
2522 task->tk_action = rpc_exit_task;
2523 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2524 dprintk("RPC: %5u %s result %d\n",
2525 task->tk_pid, __func__, task->tk_status);
2526 return;
2527 case -EAGAIN:
2528 task->tk_status = 0;
2529 if (task->tk_client->cl_discrtry)
2530 xprt_conditional_disconnect(req->rq_xprt,
2531 req->rq_connect_cookie);
2532 task->tk_action = call_encode;
2533 rpc_check_timeout(task);
2534 break;
2535 case -EKEYREJECTED:
2536 task->tk_action = call_reserve;
2537 rpc_check_timeout(task);
2538 rpcauth_invalcred(task);
2539 /* Ensure we obtain a new XID if we retry! */
2540 xprt_release(task);
2541 }
2542 }
2543
2544 static int
2545 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2546 {
2547 struct rpc_clnt *clnt = task->tk_client;
2548 struct rpc_rqst *req = task->tk_rqstp;
2549 __be32 *p;
2550 int error;
2551
2552 error = -EMSGSIZE;
2553 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2554 if (!p)
2555 goto out_fail;
2556 *p++ = req->rq_xid;
2557 *p++ = rpc_call;
2558 *p++ = cpu_to_be32(RPC_VERSION);
2559 *p++ = cpu_to_be32(clnt->cl_prog);
2560 *p++ = cpu_to_be32(clnt->cl_vers);
2561 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2562
2563 error = rpcauth_marshcred(task, xdr);
2564 if (error < 0)
2565 goto out_fail;
2566 return 0;
2567 out_fail:
2568 trace_rpc_bad_callhdr(task);
2569 rpc_call_rpcerror(task, error);
2570 return error;
2571 }
2572
2573 static noinline int
2574 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2575 {
2576 struct rpc_clnt *clnt = task->tk_client;
2577 int error;
2578 __be32 *p;
2579
2580 /* RFC-1014 says that the representation of XDR data must be a
2581 * multiple of four bytes
2582 * - if it isn't pointer subtraction in the NFS client may give
2583 * undefined results
2584 */
2585 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2586 goto out_unparsable;
2587
2588 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2589 if (!p)
2590 goto out_unparsable;
2591 p++; /* skip XID */
2592 if (*p++ != rpc_reply)
2593 goto out_unparsable;
2594 if (*p++ != rpc_msg_accepted)
2595 goto out_msg_denied;
2596
2597 error = rpcauth_checkverf(task, xdr);
2598 if (error)
2599 goto out_verifier;
2600
2601 p = xdr_inline_decode(xdr, sizeof(*p));
2602 if (!p)
2603 goto out_unparsable;
2604 switch (*p) {
2605 case rpc_success:
2606 return 0;
2607 case rpc_prog_unavail:
2608 trace_rpc__prog_unavail(task);
2609 error = -EPFNOSUPPORT;
2610 goto out_err;
2611 case rpc_prog_mismatch:
2612 trace_rpc__prog_mismatch(task);
2613 error = -EPROTONOSUPPORT;
2614 goto out_err;
2615 case rpc_proc_unavail:
2616 trace_rpc__proc_unavail(task);
2617 error = -EOPNOTSUPP;
2618 goto out_err;
2619 case rpc_garbage_args:
2620 case rpc_system_err:
2621 trace_rpc__garbage_args(task);
2622 error = -EIO;
2623 break;
2624 default:
2625 goto out_unparsable;
2626 }
2627
2628 out_garbage:
2629 clnt->cl_stats->rpcgarbage++;
2630 if (task->tk_garb_retry) {
2631 task->tk_garb_retry--;
2632 task->tk_action = call_encode;
2633 return -EAGAIN;
2634 }
2635 out_err:
2636 rpc_call_rpcerror(task, error);
2637 return error;
2638
2639 out_unparsable:
2640 trace_rpc__unparsable(task);
2641 error = -EIO;
2642 goto out_garbage;
2643
2644 out_verifier:
2645 trace_rpc_bad_verifier(task);
2646 goto out_garbage;
2647
2648 out_msg_denied:
2649 error = -EACCES;
2650 p = xdr_inline_decode(xdr, sizeof(*p));
2651 if (!p)
2652 goto out_unparsable;
2653 switch (*p++) {
2654 case rpc_auth_error:
2655 break;
2656 case rpc_mismatch:
2657 trace_rpc__mismatch(task);
2658 error = -EPROTONOSUPPORT;
2659 goto out_err;
2660 default:
2661 goto out_unparsable;
2662 }
2663
2664 p = xdr_inline_decode(xdr, sizeof(*p));
2665 if (!p)
2666 goto out_unparsable;
2667 switch (*p++) {
2668 case rpc_autherr_rejectedcred:
2669 case rpc_autherr_rejectedverf:
2670 case rpcsec_gsserr_credproblem:
2671 case rpcsec_gsserr_ctxproblem:
2672 if (!task->tk_cred_retry)
2673 break;
2674 task->tk_cred_retry--;
2675 trace_rpc__stale_creds(task);
2676 return -EKEYREJECTED;
2677 case rpc_autherr_badcred:
2678 case rpc_autherr_badverf:
2679 /* possibly garbled cred/verf? */
2680 if (!task->tk_garb_retry)
2681 break;
2682 task->tk_garb_retry--;
2683 trace_rpc__bad_creds(task);
2684 task->tk_action = call_encode;
2685 return -EAGAIN;
2686 case rpc_autherr_tooweak:
2687 trace_rpc__auth_tooweak(task);
2688 pr_warn("RPC: server %s requires stronger authentication.\n",
2689 task->tk_xprt->servername);
2690 break;
2691 default:
2692 goto out_unparsable;
2693 }
2694 goto out_err;
2695 }
2696
2697 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2698 const void *obj)
2699 {
2700 }
2701
2702 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2703 void *obj)
2704 {
2705 return 0;
2706 }
2707
2708 static const struct rpc_procinfo rpcproc_null = {
2709 .p_encode = rpcproc_encode_null,
2710 .p_decode = rpcproc_decode_null,
2711 };
2712
2713 static int rpc_ping(struct rpc_clnt *clnt)
2714 {
2715 struct rpc_message msg = {
2716 .rpc_proc = &rpcproc_null,
2717 };
2718 int err;
2719 err = rpc_call_sync(clnt, &msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2720 RPC_TASK_NULLCREDS);
2721 return err;
2722 }
2723
2724 static
2725 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2726 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2727 const struct rpc_call_ops *ops, void *data)
2728 {
2729 struct rpc_message msg = {
2730 .rpc_proc = &rpcproc_null,
2731 };
2732 struct rpc_task_setup task_setup_data = {
2733 .rpc_client = clnt,
2734 .rpc_xprt = xprt,
2735 .rpc_message = &msg,
2736 .rpc_op_cred = cred,
2737 .callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
2738 .callback_data = data,
2739 .flags = flags | RPC_TASK_NULLCREDS,
2740 };
2741
2742 return rpc_run_task(&task_setup_data);
2743 }
2744
2745 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2746 {
2747 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2748 }
2749 EXPORT_SYMBOL_GPL(rpc_call_null);
2750
2751 struct rpc_cb_add_xprt_calldata {
2752 struct rpc_xprt_switch *xps;
2753 struct rpc_xprt *xprt;
2754 };
2755
2756 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2757 {
2758 struct rpc_cb_add_xprt_calldata *data = calldata;
2759
2760 if (task->tk_status == 0)
2761 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2762 }
2763
2764 static void rpc_cb_add_xprt_release(void *calldata)
2765 {
2766 struct rpc_cb_add_xprt_calldata *data = calldata;
2767
2768 xprt_put(data->xprt);
2769 xprt_switch_put(data->xps);
2770 kfree(data);
2771 }
2772
2773 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2774 .rpc_call_done = rpc_cb_add_xprt_done,
2775 .rpc_release = rpc_cb_add_xprt_release,
2776 };
2777
2778 /**
2779 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2780 * @clnt: pointer to struct rpc_clnt
2781 * @xps: pointer to struct rpc_xprt_switch,
2782 * @xprt: pointer struct rpc_xprt
2783 * @dummy: unused
2784 */
2785 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2786 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2787 void *dummy)
2788 {
2789 struct rpc_cb_add_xprt_calldata *data;
2790 struct rpc_task *task;
2791
2792 data = kmalloc(sizeof(*data), GFP_NOFS);
2793 if (!data)
2794 return -ENOMEM;
2795 data->xps = xprt_switch_get(xps);
2796 data->xprt = xprt_get(xprt);
2797 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2798 rpc_cb_add_xprt_release(data);
2799 goto success;
2800 }
2801
2802 task = rpc_call_null_helper(clnt, xprt, NULL,
2803 RPC_TASK_SOFT|RPC_TASK_SOFTCONN|RPC_TASK_ASYNC|RPC_TASK_NULLCREDS,
2804 &rpc_cb_add_xprt_call_ops, data);
2805 if (IS_ERR(task))
2806 return PTR_ERR(task);
2807 rpc_put_task(task);
2808 success:
2809 return 1;
2810 }
2811 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2812
2813 /**
2814 * rpc_clnt_setup_test_and_add_xprt()
2815 *
2816 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
2817 * 1) caller of the test function must dereference the rpc_xprt_switch
2818 * and the rpc_xprt.
2819 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
2820 * the rpc_call_done routine.
2821 *
2822 * Upon success (return of 1), the test function adds the new
2823 * transport to the rpc_clnt xprt switch
2824 *
2825 * @clnt: struct rpc_clnt to get the new transport
2826 * @xps: the rpc_xprt_switch to hold the new transport
2827 * @xprt: the rpc_xprt to test
2828 * @data: a struct rpc_add_xprt_test pointer that holds the test function
2829 * and test function call data
2830 */
2831 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
2832 struct rpc_xprt_switch *xps,
2833 struct rpc_xprt *xprt,
2834 void *data)
2835 {
2836 struct rpc_task *task;
2837 struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
2838 int status = -EADDRINUSE;
2839
2840 xprt = xprt_get(xprt);
2841 xprt_switch_get(xps);
2842
2843 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
2844 goto out_err;
2845
2846 /* Test the connection */
2847 task = rpc_call_null_helper(clnt, xprt, NULL,
2848 RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2849 NULL, NULL);
2850 if (IS_ERR(task)) {
2851 status = PTR_ERR(task);
2852 goto out_err;
2853 }
2854 status = task->tk_status;
2855 rpc_put_task(task);
2856
2857 if (status < 0)
2858 goto out_err;
2859
2860 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
2861 xtest->add_xprt_test(clnt, xprt, xtest->data);
2862
2863 xprt_put(xprt);
2864 xprt_switch_put(xps);
2865
2866 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
2867 return 1;
2868 out_err:
2869 xprt_put(xprt);
2870 xprt_switch_put(xps);
2871 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not added\n",
2872 status, xprt->address_strings[RPC_DISPLAY_ADDR]);
2873 return status;
2874 }
2875 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
2876
2877 /**
2878 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
2879 * @clnt: pointer to struct rpc_clnt
2880 * @xprtargs: pointer to struct xprt_create
2881 * @setup: callback to test and/or set up the connection
2882 * @data: pointer to setup function data
2883 *
2884 * Creates a new transport using the parameters set in args and
2885 * adds it to clnt.
2886 * If ping is set, then test that connectivity succeeds before
2887 * adding the new transport.
2888 *
2889 */
2890 int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
2891 struct xprt_create *xprtargs,
2892 int (*setup)(struct rpc_clnt *,
2893 struct rpc_xprt_switch *,
2894 struct rpc_xprt *,
2895 void *),
2896 void *data)
2897 {
2898 struct rpc_xprt_switch *xps;
2899 struct rpc_xprt *xprt;
2900 unsigned long connect_timeout;
2901 unsigned long reconnect_timeout;
2902 unsigned char resvport, reuseport;
2903 int ret = 0;
2904
2905 rcu_read_lock();
2906 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2907 xprt = xprt_iter_xprt(&clnt->cl_xpi);
2908 if (xps == NULL || xprt == NULL) {
2909 rcu_read_unlock();
2910 xprt_switch_put(xps);
2911 return -EAGAIN;
2912 }
2913 resvport = xprt->resvport;
2914 reuseport = xprt->reuseport;
2915 connect_timeout = xprt->connect_timeout;
2916 reconnect_timeout = xprt->max_reconnect_timeout;
2917 rcu_read_unlock();
2918
2919 xprt = xprt_create_transport(xprtargs);
2920 if (IS_ERR(xprt)) {
2921 ret = PTR_ERR(xprt);
2922 goto out_put_switch;
2923 }
2924 xprt->resvport = resvport;
2925 xprt->reuseport = reuseport;
2926 if (xprt->ops->set_connect_timeout != NULL)
2927 xprt->ops->set_connect_timeout(xprt,
2928 connect_timeout,
2929 reconnect_timeout);
2930
2931 rpc_xprt_switch_set_roundrobin(xps);
2932 if (setup) {
2933 ret = setup(clnt, xps, xprt, data);
2934 if (ret != 0)
2935 goto out_put_xprt;
2936 }
2937 rpc_xprt_switch_add_xprt(xps, xprt);
2938 out_put_xprt:
2939 xprt_put(xprt);
2940 out_put_switch:
2941 xprt_switch_put(xps);
2942 return ret;
2943 }
2944 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
2945
2946 struct connect_timeout_data {
2947 unsigned long connect_timeout;
2948 unsigned long reconnect_timeout;
2949 };
2950
2951 static int
2952 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
2953 struct rpc_xprt *xprt,
2954 void *data)
2955 {
2956 struct connect_timeout_data *timeo = data;
2957
2958 if (xprt->ops->set_connect_timeout)
2959 xprt->ops->set_connect_timeout(xprt,
2960 timeo->connect_timeout,
2961 timeo->reconnect_timeout);
2962 return 0;
2963 }
2964
2965 void
2966 rpc_set_connect_timeout(struct rpc_clnt *clnt,
2967 unsigned long connect_timeout,
2968 unsigned long reconnect_timeout)
2969 {
2970 struct connect_timeout_data timeout = {
2971 .connect_timeout = connect_timeout,
2972 .reconnect_timeout = reconnect_timeout,
2973 };
2974 rpc_clnt_iterate_for_each_xprt(clnt,
2975 rpc_xprt_set_connect_timeout,
2976 &timeout);
2977 }
2978 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
2979
2980 void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
2981 {
2982 rcu_read_lock();
2983 xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
2984 rcu_read_unlock();
2985 }
2986 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
2987
2988 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
2989 {
2990 rcu_read_lock();
2991 rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
2992 xprt);
2993 rcu_read_unlock();
2994 }
2995 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
2996
2997 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
2998 const struct sockaddr *sap)
2999 {
3000 struct rpc_xprt_switch *xps;
3001 bool ret;
3002
3003 rcu_read_lock();
3004 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3005 ret = rpc_xprt_switch_has_addr(xps, sap);
3006 rcu_read_unlock();
3007 return ret;
3008 }
3009 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3010
3011 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3012 static void rpc_show_header(void)
3013 {
3014 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3015 "-timeout ---ops--\n");
3016 }
3017
3018 static void rpc_show_task(const struct rpc_clnt *clnt,
3019 const struct rpc_task *task)
3020 {
3021 const char *rpc_waitq = "none";
3022
3023 if (RPC_IS_QUEUED(task))
3024 rpc_waitq = rpc_qname(task->tk_waitqueue);
3025
3026 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3027 task->tk_pid, task->tk_flags, task->tk_status,
3028 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3029 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3030 task->tk_action, rpc_waitq);
3031 }
3032
3033 void rpc_show_tasks(struct net *net)
3034 {
3035 struct rpc_clnt *clnt;
3036 struct rpc_task *task;
3037 int header = 0;
3038 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3039
3040 spin_lock(&sn->rpc_client_lock);
3041 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3042 spin_lock(&clnt->cl_lock);
3043 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3044 if (!header) {
3045 rpc_show_header();
3046 header++;
3047 }
3048 rpc_show_task(clnt, task);
3049 }
3050 spin_unlock(&clnt->cl_lock);
3051 }
3052 spin_unlock(&sn->rpc_client_lock);
3053 }
3054 #endif
3055
3056 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3057 static int
3058 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3059 struct rpc_xprt *xprt,
3060 void *dummy)
3061 {
3062 return xprt_enable_swap(xprt);
3063 }
3064
3065 int
3066 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3067 {
3068 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3069 return rpc_clnt_iterate_for_each_xprt(clnt,
3070 rpc_clnt_swap_activate_callback, NULL);
3071 return 0;
3072 }
3073 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3074
3075 static int
3076 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3077 struct rpc_xprt *xprt,
3078 void *dummy)
3079 {
3080 xprt_disable_swap(xprt);
3081 return 0;
3082 }
3083
3084 void
3085 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3086 {
3087 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3088 rpc_clnt_iterate_for_each_xprt(clnt,
3089 rpc_clnt_swap_deactivate_callback, NULL);
3090 }
3091 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3092 #endif /* CONFIG_SUNRPC_SWAP */
Linux with added FPC-III support