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