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drm/tests: hdmi: Fix memory leaks in drm_display_mode_from_cea_vic()
[drm/drm-misc.git] / net / sunrpc / clnt.c
blob0090162ee8c350568c91f1bcd951675ac3ae141c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/net/sunrpc/clnt.c
4 *
5 * This file contains the high-level RPC interface.
6 * It is modeled as a finite state machine to support both synchronous
7 * and asynchronous requests.
8 *
9 * - RPC header generation and argument serialization.
10 * - Credential refresh.
11 * - TCP connect handling.
12 * - Retry of operation when it is suspected the operation failed because
13 * of uid squashing on the server, or when the credentials were stale
14 * and need to be refreshed, or when a packet was damaged in transit.
15 * This may be have to be moved to the VFS layer.
16 *
17 * Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
18 * Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
19 */
20
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/kallsyms.h>
25 #include <linux/mm.h>
26 #include <linux/namei.h>
27 #include <linux/mount.h>
28 #include <linux/slab.h>
29 #include <linux/rcupdate.h>
30 #include <linux/utsname.h>
31 #include <linux/workqueue.h>
32 #include <linux/in.h>
33 #include <linux/in6.h>
34 #include <linux/un.h>
35
36 #include <linux/sunrpc/clnt.h>
37 #include <linux/sunrpc/addr.h>
38 #include <linux/sunrpc/rpc_pipe_fs.h>
39 #include <linux/sunrpc/metrics.h>
40 #include <linux/sunrpc/bc_xprt.h>
41 #include <trace/events/sunrpc.h>
42
43 #include "sunrpc.h"
44 #include "sysfs.h"
45 #include "netns.h"
46
47 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
48 # define RPCDBG_FACILITY RPCDBG_CALL
49 #endif
50
51 static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
52
53 static void call_start(struct rpc_task *task);
54 static void call_reserve(struct rpc_task *task);
55 static void call_reserveresult(struct rpc_task *task);
56 static void call_allocate(struct rpc_task *task);
57 static void call_encode(struct rpc_task *task);
58 static void call_decode(struct rpc_task *task);
59 static void call_bind(struct rpc_task *task);
60 static void call_bind_status(struct rpc_task *task);
61 static void call_transmit(struct rpc_task *task);
62 static void call_status(struct rpc_task *task);
63 static void call_transmit_status(struct rpc_task *task);
64 static void call_refresh(struct rpc_task *task);
65 static void call_refreshresult(struct rpc_task *task);
66 static void call_connect(struct rpc_task *task);
67 static void call_connect_status(struct rpc_task *task);
68
69 static int rpc_encode_header(struct rpc_task *task,
70 struct xdr_stream *xdr);
71 static int rpc_decode_header(struct rpc_task *task,
72 struct xdr_stream *xdr);
73 static int rpc_ping(struct rpc_clnt *clnt);
74 static int rpc_ping_noreply(struct rpc_clnt *clnt);
75 static void rpc_check_timeout(struct rpc_task *task);
76
77 static void rpc_register_client(struct rpc_clnt *clnt)
78 {
79 struct net *net = rpc_net_ns(clnt);
80 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
81
82 spin_lock(&sn->rpc_client_lock);
83 list_add(&clnt->cl_clients, &sn->all_clients);
84 spin_unlock(&sn->rpc_client_lock);
85 }
86
87 static void rpc_unregister_client(struct rpc_clnt *clnt)
88 {
89 struct net *net = rpc_net_ns(clnt);
90 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
91
92 spin_lock(&sn->rpc_client_lock);
93 list_del(&clnt->cl_clients);
94 spin_unlock(&sn->rpc_client_lock);
95 }
96
97 static void __rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
98 {
99 rpc_remove_client_dir(clnt);
100 }
101
102 static void rpc_clnt_remove_pipedir(struct rpc_clnt *clnt)
103 {
104 struct net *net = rpc_net_ns(clnt);
105 struct super_block *pipefs_sb;
106
107 pipefs_sb = rpc_get_sb_net(net);
108 if (pipefs_sb) {
109 if (pipefs_sb == clnt->pipefs_sb)
110 __rpc_clnt_remove_pipedir(clnt);
111 rpc_put_sb_net(net);
112 }
113 }
114
115 static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
116 struct rpc_clnt *clnt)
117 {
118 static uint32_t clntid;
119 const char *dir_name = clnt->cl_program->pipe_dir_name;
120 char name[15];
121 struct dentry *dir, *dentry;
122
123 dir = rpc_d_lookup_sb(sb, dir_name);
124 if (dir == NULL) {
125 pr_info("RPC: pipefs directory doesn't exist: %s\n", dir_name);
126 return dir;
127 }
128 for (;;) {
129 snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
130 name[sizeof(name) - 1] = '\0';
131 dentry = rpc_create_client_dir(dir, name, clnt);
132 if (!IS_ERR(dentry))
133 break;
134 if (dentry == ERR_PTR(-EEXIST))
135 continue;
136 printk(KERN_INFO "RPC: Couldn't create pipefs entry"
137 " %s/%s, error %ld\n",
138 dir_name, name, PTR_ERR(dentry));
139 break;
140 }
141 dput(dir);
142 return dentry;
143 }
144
145 static int
146 rpc_setup_pipedir(struct super_block *pipefs_sb, struct rpc_clnt *clnt)
147 {
148 struct dentry *dentry;
149
150 clnt->pipefs_sb = pipefs_sb;
151
152 if (clnt->cl_program->pipe_dir_name != NULL) {
153 dentry = rpc_setup_pipedir_sb(pipefs_sb, clnt);
154 if (IS_ERR(dentry))
155 return PTR_ERR(dentry);
156 }
157 return 0;
158 }
159
160 static int rpc_clnt_skip_event(struct rpc_clnt *clnt, unsigned long event)
161 {
162 if (clnt->cl_program->pipe_dir_name == NULL)
163 return 1;
164
165 switch (event) {
166 case RPC_PIPEFS_MOUNT:
167 if (clnt->cl_pipedir_objects.pdh_dentry != NULL)
168 return 1;
169 if (refcount_read(&clnt->cl_count) == 0)
170 return 1;
171 break;
172 case RPC_PIPEFS_UMOUNT:
173 if (clnt->cl_pipedir_objects.pdh_dentry == NULL)
174 return 1;
175 break;
176 }
177 return 0;
178 }
179
180 static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
181 struct super_block *sb)
182 {
183 struct dentry *dentry;
184
185 switch (event) {
186 case RPC_PIPEFS_MOUNT:
187 dentry = rpc_setup_pipedir_sb(sb, clnt);
188 if (!dentry)
189 return -ENOENT;
190 if (IS_ERR(dentry))
191 return PTR_ERR(dentry);
192 break;
193 case RPC_PIPEFS_UMOUNT:
194 __rpc_clnt_remove_pipedir(clnt);
195 break;
196 default:
197 printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
198 return -ENOTSUPP;
199 }
200 return 0;
201 }
202
203 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
204 struct super_block *sb)
205 {
206 int error = 0;
207
208 for (;; clnt = clnt->cl_parent) {
209 if (!rpc_clnt_skip_event(clnt, event))
210 error = __rpc_clnt_handle_event(clnt, event, sb);
211 if (error || clnt == clnt->cl_parent)
212 break;
213 }
214 return error;
215 }
216
217 static struct rpc_clnt *rpc_get_client_for_event(struct net *net, int event)
218 {
219 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
220 struct rpc_clnt *clnt;
221
222 spin_lock(&sn->rpc_client_lock);
223 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
224 if (rpc_clnt_skip_event(clnt, event))
225 continue;
226 spin_unlock(&sn->rpc_client_lock);
227 return clnt;
228 }
229 spin_unlock(&sn->rpc_client_lock);
230 return NULL;
231 }
232
233 static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
234 void *ptr)
235 {
236 struct super_block *sb = ptr;
237 struct rpc_clnt *clnt;
238 int error = 0;
239
240 while ((clnt = rpc_get_client_for_event(sb->s_fs_info, event))) {
241 error = __rpc_pipefs_event(clnt, event, sb);
242 if (error)
243 break;
244 }
245 return error;
246 }
247
248 static struct notifier_block rpc_clients_block = {
249 .notifier_call = rpc_pipefs_event,
250 .priority = SUNRPC_PIPEFS_RPC_PRIO,
251 };
252
253 int rpc_clients_notifier_register(void)
254 {
255 return rpc_pipefs_notifier_register(&rpc_clients_block);
256 }
257
258 void rpc_clients_notifier_unregister(void)
259 {
260 return rpc_pipefs_notifier_unregister(&rpc_clients_block);
261 }
262
263 static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
264 struct rpc_xprt *xprt,
265 const struct rpc_timeout *timeout)
266 {
267 struct rpc_xprt *old;
268
269 spin_lock(&clnt->cl_lock);
270 old = rcu_dereference_protected(clnt->cl_xprt,
271 lockdep_is_held(&clnt->cl_lock));
272
273 if (!xprt_bound(xprt))
274 clnt->cl_autobind = 1;
275
276 clnt->cl_timeout = timeout;
277 rcu_assign_pointer(clnt->cl_xprt, xprt);
278 spin_unlock(&clnt->cl_lock);
279
280 return old;
281 }
282
283 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
284 {
285 ssize_t copied;
286
287 copied = strscpy(clnt->cl_nodename,
288 nodename, sizeof(clnt->cl_nodename));
289
290 clnt->cl_nodelen = copied < 0
291 ? sizeof(clnt->cl_nodename) - 1
292 : copied;
293 }
294
295 static int rpc_client_register(struct rpc_clnt *clnt,
296 rpc_authflavor_t pseudoflavor,
297 const char *client_name)
298 {
299 struct rpc_auth_create_args auth_args = {
300 .pseudoflavor = pseudoflavor,
301 .target_name = client_name,
302 };
303 struct rpc_auth *auth;
304 struct net *net = rpc_net_ns(clnt);
305 struct super_block *pipefs_sb;
306 int err;
307
308 rpc_clnt_debugfs_register(clnt);
309
310 pipefs_sb = rpc_get_sb_net(net);
311 if (pipefs_sb) {
312 err = rpc_setup_pipedir(pipefs_sb, clnt);
313 if (err)
314 goto out;
315 }
316
317 rpc_register_client(clnt);
318 if (pipefs_sb)
319 rpc_put_sb_net(net);
320
321 auth = rpcauth_create(&auth_args, clnt);
322 if (IS_ERR(auth)) {
323 dprintk("RPC: Couldn't create auth handle (flavor %u)\n",
324 pseudoflavor);
325 err = PTR_ERR(auth);
326 goto err_auth;
327 }
328 return 0;
329 err_auth:
330 pipefs_sb = rpc_get_sb_net(net);
331 rpc_unregister_client(clnt);
332 __rpc_clnt_remove_pipedir(clnt);
333 out:
334 if (pipefs_sb)
335 rpc_put_sb_net(net);
336 rpc_sysfs_client_destroy(clnt);
337 rpc_clnt_debugfs_unregister(clnt);
338 return err;
339 }
340
341 static DEFINE_IDA(rpc_clids);
342
343 void rpc_cleanup_clids(void)
344 {
345 ida_destroy(&rpc_clids);
346 }
347
348 static int rpc_alloc_clid(struct rpc_clnt *clnt)
349 {
350 int clid;
351
352 clid = ida_alloc(&rpc_clids, GFP_KERNEL);
353 if (clid < 0)
354 return clid;
355 clnt->cl_clid = clid;
356 return 0;
357 }
358
359 static void rpc_free_clid(struct rpc_clnt *clnt)
360 {
361 ida_free(&rpc_clids, clnt->cl_clid);
362 }
363
364 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
365 struct rpc_xprt_switch *xps,
366 struct rpc_xprt *xprt,
367 struct rpc_clnt *parent)
368 {
369 const struct rpc_program *program = args->program;
370 const struct rpc_version *version;
371 struct rpc_clnt *clnt = NULL;
372 const struct rpc_timeout *timeout;
373 const char *nodename = args->nodename;
374 int err;
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 clnt->cl_xprtsec = args->xprtsec;
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 = args->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->main = true;
422 xprt_iter_init(&clnt->cl_xpi, xps);
423 xprt_switch_put(xps);
424
425 clnt->cl_rtt = &clnt->cl_rtt_default;
426 rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
427
428 refcount_set(&clnt->cl_count, 1);
429
430 if (nodename == NULL)
431 nodename = utsname()->nodename;
432 /* save the nodename */
433 rpc_clnt_set_nodename(clnt, nodename);
434
435 rpc_sysfs_client_setup(clnt, xps, rpc_net_ns(clnt));
436 err = rpc_client_register(clnt, args->authflavor, args->client_name);
437 if (err)
438 goto out_no_path;
439 if (parent)
440 refcount_inc(&parent->cl_count);
441
442 trace_rpc_clnt_new(clnt, xprt, args);
443 return clnt;
444
445 out_no_path:
446 rpc_free_iostats(clnt->cl_metrics);
447 out_no_stats:
448 put_cred(clnt->cl_cred);
449 rpc_free_clid(clnt);
450 out_no_clid:
451 kfree(clnt);
452 out_err:
453 rpciod_down();
454 out_no_rpciod:
455 xprt_switch_put(xps);
456 xprt_put(xprt);
457 trace_rpc_clnt_new_err(program->name, args->servername, err);
458 return ERR_PTR(err);
459 }
460
461 static struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
462 struct rpc_xprt *xprt)
463 {
464 struct rpc_clnt *clnt = NULL;
465 struct rpc_xprt_switch *xps;
466
467 if (args->bc_xprt && args->bc_xprt->xpt_bc_xps) {
468 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
469 xps = args->bc_xprt->xpt_bc_xps;
470 xprt_switch_get(xps);
471 } else {
472 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
473 if (xps == NULL) {
474 xprt_put(xprt);
475 return ERR_PTR(-ENOMEM);
476 }
477 if (xprt->bc_xprt) {
478 xprt_switch_get(xps);
479 xprt->bc_xprt->xpt_bc_xps = xps;
480 }
481 }
482 clnt = rpc_new_client(args, xps, xprt, NULL);
483 if (IS_ERR(clnt))
484 return clnt;
485
486 if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
487 int err = rpc_ping(clnt);
488 if (err != 0) {
489 rpc_shutdown_client(clnt);
490 return ERR_PTR(err);
491 }
492 } else if (args->flags & RPC_CLNT_CREATE_CONNECTED) {
493 int err = rpc_ping_noreply(clnt);
494 if (err != 0) {
495 rpc_shutdown_client(clnt);
496 return ERR_PTR(err);
497 }
498 }
499
500 clnt->cl_softrtry = 1;
501 if (args->flags & (RPC_CLNT_CREATE_HARDRTRY|RPC_CLNT_CREATE_SOFTERR)) {
502 clnt->cl_softrtry = 0;
503 if (args->flags & RPC_CLNT_CREATE_SOFTERR)
504 clnt->cl_softerr = 1;
505 }
506
507 if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
508 clnt->cl_autobind = 1;
509 if (args->flags & RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT)
510 clnt->cl_noretranstimeo = 1;
511 if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
512 clnt->cl_discrtry = 1;
513 if (!(args->flags & RPC_CLNT_CREATE_QUIET))
514 clnt->cl_chatty = 1;
515
516 return clnt;
517 }
518
519 /**
520 * rpc_create - create an RPC client and transport with one call
521 * @args: rpc_clnt create argument structure
522 *
523 * Creates and initializes an RPC transport and an RPC client.
524 *
525 * It can ping the server in order to determine if it is up, and to see if
526 * it supports this program and version. RPC_CLNT_CREATE_NOPING disables
527 * this behavior so asynchronous tasks can also use rpc_create.
528 */
529 struct rpc_clnt *rpc_create(struct rpc_create_args *args)
530 {
531 struct rpc_xprt *xprt;
532 struct xprt_create xprtargs = {
533 .net = args->net,
534 .ident = args->protocol,
535 .srcaddr = args->saddress,
536 .dstaddr = args->address,
537 .addrlen = args->addrsize,
538 .servername = args->servername,
539 .bc_xprt = args->bc_xprt,
540 .xprtsec = args->xprtsec,
541 .connect_timeout = args->connect_timeout,
542 .reconnect_timeout = args->reconnect_timeout,
543 };
544 char servername[RPC_MAXNETNAMELEN];
545 struct rpc_clnt *clnt;
546 int i;
547
548 if (args->bc_xprt) {
549 WARN_ON_ONCE(!(args->protocol & XPRT_TRANSPORT_BC));
550 xprt = args->bc_xprt->xpt_bc_xprt;
551 if (xprt) {
552 xprt_get(xprt);
553 return rpc_create_xprt(args, xprt);
554 }
555 }
556
557 if (args->flags & RPC_CLNT_CREATE_INFINITE_SLOTS)
558 xprtargs.flags |= XPRT_CREATE_INFINITE_SLOTS;
559 if (args->flags & RPC_CLNT_CREATE_NO_IDLE_TIMEOUT)
560 xprtargs.flags |= XPRT_CREATE_NO_IDLE_TIMEOUT;
561 /*
562 * If the caller chooses not to specify a hostname, whip
563 * up a string representation of the passed-in address.
564 */
565 if (xprtargs.servername == NULL) {
566 struct sockaddr_un *sun =
567 (struct sockaddr_un *)args->address;
568 struct sockaddr_in *sin =
569 (struct sockaddr_in *)args->address;
570 struct sockaddr_in6 *sin6 =
571 (struct sockaddr_in6 *)args->address;
572
573 servername[0] = '\0';
574 switch (args->address->sa_family) {
575 case AF_LOCAL:
576 if (sun->sun_path[0])
577 snprintf(servername, sizeof(servername), "%s",
578 sun->sun_path);
579 else
580 snprintf(servername, sizeof(servername), "@%s",
581 sun->sun_path+1);
582 break;
583 case AF_INET:
584 snprintf(servername, sizeof(servername), "%pI4",
585 &sin->sin_addr.s_addr);
586 break;
587 case AF_INET6:
588 snprintf(servername, sizeof(servername), "%pI6",
589 &sin6->sin6_addr);
590 break;
591 default:
592 /* caller wants default server name, but
593 * address family isn't recognized. */
594 return ERR_PTR(-EINVAL);
595 }
596 xprtargs.servername = servername;
597 }
598
599 xprt = xprt_create_transport(&xprtargs);
600 if (IS_ERR(xprt))
601 return (struct rpc_clnt *)xprt;
602
603 /*
604 * By default, kernel RPC client connects from a reserved port.
605 * CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
606 * but it is always enabled for rpciod, which handles the connect
607 * operation.
608 */
609 xprt->resvport = 1;
610 if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
611 xprt->resvport = 0;
612 xprt->reuseport = 0;
613 if (args->flags & RPC_CLNT_CREATE_REUSEPORT)
614 xprt->reuseport = 1;
615
616 clnt = rpc_create_xprt(args, xprt);
617 if (IS_ERR(clnt) || args->nconnect <= 1)
618 return clnt;
619
620 for (i = 0; i < args->nconnect - 1; i++) {
621 if (rpc_clnt_add_xprt(clnt, &xprtargs, NULL, NULL) < 0)
622 break;
623 }
624 return clnt;
625 }
626 EXPORT_SYMBOL_GPL(rpc_create);
627
628 /*
629 * This function clones the RPC client structure. It allows us to share the
630 * same transport while varying parameters such as the authentication
631 * flavour.
632 */
633 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
634 struct rpc_clnt *clnt)
635 {
636 struct rpc_xprt_switch *xps;
637 struct rpc_xprt *xprt;
638 struct rpc_clnt *new;
639 int err;
640
641 err = -ENOMEM;
642 rcu_read_lock();
643 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
644 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
645 rcu_read_unlock();
646 if (xprt == NULL || xps == NULL) {
647 xprt_put(xprt);
648 xprt_switch_put(xps);
649 goto out_err;
650 }
651 args->servername = xprt->servername;
652 args->nodename = clnt->cl_nodename;
653
654 new = rpc_new_client(args, xps, xprt, clnt);
655 if (IS_ERR(new))
656 return new;
657
658 /* Turn off autobind on clones */
659 new->cl_autobind = 0;
660 new->cl_softrtry = clnt->cl_softrtry;
661 new->cl_softerr = clnt->cl_softerr;
662 new->cl_noretranstimeo = clnt->cl_noretranstimeo;
663 new->cl_discrtry = clnt->cl_discrtry;
664 new->cl_chatty = clnt->cl_chatty;
665 new->cl_principal = clnt->cl_principal;
666 new->cl_max_connect = clnt->cl_max_connect;
667 return new;
668
669 out_err:
670 trace_rpc_clnt_clone_err(clnt, err);
671 return ERR_PTR(err);
672 }
673
674 /**
675 * rpc_clone_client - Clone an RPC client structure
676 *
677 * @clnt: RPC client whose parameters are copied
678 *
679 * Returns a fresh RPC client or an ERR_PTR.
680 */
681 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *clnt)
682 {
683 struct rpc_create_args args = {
684 .program = clnt->cl_program,
685 .prognumber = clnt->cl_prog,
686 .version = clnt->cl_vers,
687 .authflavor = clnt->cl_auth->au_flavor,
688 .cred = clnt->cl_cred,
689 .stats = clnt->cl_stats,
690 };
691 return __rpc_clone_client(&args, clnt);
692 }
693 EXPORT_SYMBOL_GPL(rpc_clone_client);
694
695 /**
696 * rpc_clone_client_set_auth - Clone an RPC client structure and set its auth
697 *
698 * @clnt: RPC client whose parameters are copied
699 * @flavor: security flavor for new client
700 *
701 * Returns a fresh RPC client or an ERR_PTR.
702 */
703 struct rpc_clnt *
704 rpc_clone_client_set_auth(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
705 {
706 struct rpc_create_args args = {
707 .program = clnt->cl_program,
708 .prognumber = clnt->cl_prog,
709 .version = clnt->cl_vers,
710 .authflavor = flavor,
711 .cred = clnt->cl_cred,
712 .stats = clnt->cl_stats,
713 };
714 return __rpc_clone_client(&args, clnt);
715 }
716 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
717
718 /**
719 * rpc_switch_client_transport: switch the RPC transport on the fly
720 * @clnt: pointer to a struct rpc_clnt
721 * @args: pointer to the new transport arguments
722 * @timeout: pointer to the new timeout parameters
723 *
724 * This function allows the caller to switch the RPC transport for the
725 * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
726 * server, for instance. It assumes that the caller has ensured that
727 * there are no active RPC tasks by using some form of locking.
728 *
729 * Returns zero if "clnt" is now using the new xprt. Otherwise a
730 * negative errno is returned, and "clnt" continues to use the old
731 * xprt.
732 */
733 int rpc_switch_client_transport(struct rpc_clnt *clnt,
734 struct xprt_create *args,
735 const struct rpc_timeout *timeout)
736 {
737 const struct rpc_timeout *old_timeo;
738 rpc_authflavor_t pseudoflavor;
739 struct rpc_xprt_switch *xps, *oldxps;
740 struct rpc_xprt *xprt, *old;
741 struct rpc_clnt *parent;
742 int err;
743
744 args->xprtsec = clnt->cl_xprtsec;
745 xprt = xprt_create_transport(args);
746 if (IS_ERR(xprt))
747 return PTR_ERR(xprt);
748
749 xps = xprt_switch_alloc(xprt, GFP_KERNEL);
750 if (xps == NULL) {
751 xprt_put(xprt);
752 return -ENOMEM;
753 }
754
755 pseudoflavor = clnt->cl_auth->au_flavor;
756
757 old_timeo = clnt->cl_timeout;
758 old = rpc_clnt_set_transport(clnt, xprt, timeout);
759 oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
760
761 rpc_unregister_client(clnt);
762 __rpc_clnt_remove_pipedir(clnt);
763 rpc_sysfs_client_destroy(clnt);
764 rpc_clnt_debugfs_unregister(clnt);
765
766 /*
767 * A new transport was created. "clnt" therefore
768 * becomes the root of a new cl_parent tree. clnt's
769 * children, if it has any, still point to the old xprt.
770 */
771 parent = clnt->cl_parent;
772 clnt->cl_parent = clnt;
773
774 /*
775 * The old rpc_auth cache cannot be re-used. GSS
776 * contexts in particular are between a single
777 * client and server.
778 */
779 err = rpc_client_register(clnt, pseudoflavor, NULL);
780 if (err)
781 goto out_revert;
782
783 synchronize_rcu();
784 if (parent != clnt)
785 rpc_release_client(parent);
786 xprt_switch_put(oldxps);
787 xprt_put(old);
788 trace_rpc_clnt_replace_xprt(clnt);
789 return 0;
790
791 out_revert:
792 xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
793 rpc_clnt_set_transport(clnt, old, old_timeo);
794 clnt->cl_parent = parent;
795 rpc_client_register(clnt, pseudoflavor, NULL);
796 xprt_switch_put(xps);
797 xprt_put(xprt);
798 trace_rpc_clnt_replace_xprt_err(clnt);
799 return err;
800 }
801 EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
802
803 static struct rpc_xprt_switch *rpc_clnt_xprt_switch_get(struct rpc_clnt *clnt)
804 {
805 struct rpc_xprt_switch *xps;
806
807 rcu_read_lock();
808 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
809 rcu_read_unlock();
810
811 return xps;
812 }
813
814 static
815 int _rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi,
816 void func(struct rpc_xprt_iter *xpi, struct rpc_xprt_switch *xps))
817 {
818 struct rpc_xprt_switch *xps;
819
820 xps = rpc_clnt_xprt_switch_get(clnt);
821 if (xps == NULL)
822 return -EAGAIN;
823 func(xpi, xps);
824 xprt_switch_put(xps);
825 return 0;
826 }
827
828 static
829 int rpc_clnt_xprt_iter_init(struct rpc_clnt *clnt, struct rpc_xprt_iter *xpi)
830 {
831 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listall);
832 }
833
834 static
835 int rpc_clnt_xprt_iter_offline_init(struct rpc_clnt *clnt,
836 struct rpc_xprt_iter *xpi)
837 {
838 return _rpc_clnt_xprt_iter_init(clnt, xpi, xprt_iter_init_listoffline);
839 }
840
841 /**
842 * rpc_clnt_iterate_for_each_xprt - Apply a function to all transports
843 * @clnt: pointer to client
844 * @fn: function to apply
845 * @data: void pointer to function data
846 *
847 * Iterates through the list of RPC transports currently attached to the
848 * client and applies the function fn(clnt, xprt, data).
849 *
850 * On error, the iteration stops, and the function returns the error value.
851 */
852 int rpc_clnt_iterate_for_each_xprt(struct rpc_clnt *clnt,
853 int (*fn)(struct rpc_clnt *, struct rpc_xprt *, void *),
854 void *data)
855 {
856 struct rpc_xprt_iter xpi;
857 int ret;
858
859 ret = rpc_clnt_xprt_iter_init(clnt, &xpi);
860 if (ret)
861 return ret;
862 for (;;) {
863 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
864
865 if (!xprt)
866 break;
867 ret = fn(clnt, xprt, data);
868 xprt_put(xprt);
869 if (ret < 0)
870 break;
871 }
872 xprt_iter_destroy(&xpi);
873 return ret;
874 }
875 EXPORT_SYMBOL_GPL(rpc_clnt_iterate_for_each_xprt);
876
877 /*
878 * Kill all tasks for the given client.
879 * XXX: kill their descendants as well?
880 */
881 void rpc_killall_tasks(struct rpc_clnt *clnt)
882 {
883 struct rpc_task *rovr;
884
885
886 if (list_empty(&clnt->cl_tasks))
887 return;
888
889 /*
890 * Spin lock all_tasks to prevent changes...
891 */
892 trace_rpc_clnt_killall(clnt);
893 spin_lock(&clnt->cl_lock);
894 list_for_each_entry(rovr, &clnt->cl_tasks, tk_task)
895 rpc_signal_task(rovr);
896 spin_unlock(&clnt->cl_lock);
897 }
898 EXPORT_SYMBOL_GPL(rpc_killall_tasks);
899
900 /**
901 * rpc_cancel_tasks - try to cancel a set of RPC tasks
902 * @clnt: Pointer to RPC client
903 * @error: RPC task error value to set
904 * @fnmatch: Pointer to selector function
905 * @data: User data
906 *
907 * Uses @fnmatch to define a set of RPC tasks that are to be cancelled.
908 * The argument @error must be a negative error value.
909 */
910 unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
911 bool (*fnmatch)(const struct rpc_task *,
912 const void *),
913 const void *data)
914 {
915 struct rpc_task *task;
916 unsigned long count = 0;
917
918 if (list_empty(&clnt->cl_tasks))
919 return 0;
920 /*
921 * Spin lock all_tasks to prevent changes...
922 */
923 spin_lock(&clnt->cl_lock);
924 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
925 if (!RPC_IS_ACTIVATED(task))
926 continue;
927 if (!fnmatch(task, data))
928 continue;
929 rpc_task_try_cancel(task, error);
930 count++;
931 }
932 spin_unlock(&clnt->cl_lock);
933 return count;
934 }
935 EXPORT_SYMBOL_GPL(rpc_cancel_tasks);
936
937 static int rpc_clnt_disconnect_xprt(struct rpc_clnt *clnt,
938 struct rpc_xprt *xprt, void *dummy)
939 {
940 if (xprt_connected(xprt))
941 xprt_force_disconnect(xprt);
942 return 0;
943 }
944
945 void rpc_clnt_disconnect(struct rpc_clnt *clnt)
946 {
947 rpc_clnt_iterate_for_each_xprt(clnt, rpc_clnt_disconnect_xprt, NULL);
948 }
949 EXPORT_SYMBOL_GPL(rpc_clnt_disconnect);
950
951 /*
952 * Properly shut down an RPC client, terminating all outstanding
953 * requests.
954 */
955 void rpc_shutdown_client(struct rpc_clnt *clnt)
956 {
957 might_sleep();
958
959 trace_rpc_clnt_shutdown(clnt);
960
961 while (!list_empty(&clnt->cl_tasks)) {
962 rpc_killall_tasks(clnt);
963 wait_event_timeout(destroy_wait,
964 list_empty(&clnt->cl_tasks), 1*HZ);
965 }
966
967 rpc_release_client(clnt);
968 }
969 EXPORT_SYMBOL_GPL(rpc_shutdown_client);
970
971 /*
972 * Free an RPC client
973 */
974 static void rpc_free_client_work(struct work_struct *work)
975 {
976 struct rpc_clnt *clnt = container_of(work, struct rpc_clnt, cl_work);
977
978 trace_rpc_clnt_free(clnt);
979
980 /* These might block on processes that might allocate memory,
981 * so they cannot be called in rpciod, so they are handled separately
982 * here.
983 */
984 rpc_sysfs_client_destroy(clnt);
985 rpc_clnt_debugfs_unregister(clnt);
986 rpc_free_clid(clnt);
987 rpc_clnt_remove_pipedir(clnt);
988 xprt_put(rcu_dereference_raw(clnt->cl_xprt));
989
990 kfree(clnt);
991 rpciod_down();
992 }
993 static struct rpc_clnt *
994 rpc_free_client(struct rpc_clnt *clnt)
995 {
996 struct rpc_clnt *parent = NULL;
997
998 trace_rpc_clnt_release(clnt);
999 if (clnt->cl_parent != clnt)
1000 parent = clnt->cl_parent;
1001 rpc_unregister_client(clnt);
1002 rpc_free_iostats(clnt->cl_metrics);
1003 clnt->cl_metrics = NULL;
1004 xprt_iter_destroy(&clnt->cl_xpi);
1005 put_cred(clnt->cl_cred);
1006
1007 INIT_WORK(&clnt->cl_work, rpc_free_client_work);
1008 schedule_work(&clnt->cl_work);
1009 return parent;
1010 }
1011
1012 /*
1013 * Free an RPC client
1014 */
1015 static struct rpc_clnt *
1016 rpc_free_auth(struct rpc_clnt *clnt)
1017 {
1018 /*
1019 * Note: RPCSEC_GSS may need to send NULL RPC calls in order to
1020 * release remaining GSS contexts. This mechanism ensures
1021 * that it can do so safely.
1022 */
1023 if (clnt->cl_auth != NULL) {
1024 rpcauth_release(clnt->cl_auth);
1025 clnt->cl_auth = NULL;
1026 }
1027 if (refcount_dec_and_test(&clnt->cl_count))
1028 return rpc_free_client(clnt);
1029 return NULL;
1030 }
1031
1032 /*
1033 * Release reference to the RPC client
1034 */
1035 void
1036 rpc_release_client(struct rpc_clnt *clnt)
1037 {
1038 do {
1039 if (list_empty(&clnt->cl_tasks))
1040 wake_up(&destroy_wait);
1041 if (refcount_dec_not_one(&clnt->cl_count))
1042 break;
1043 clnt = rpc_free_auth(clnt);
1044 } while (clnt != NULL);
1045 }
1046 EXPORT_SYMBOL_GPL(rpc_release_client);
1047
1048 /**
1049 * rpc_bind_new_program - bind a new RPC program to an existing client
1050 * @old: old rpc_client
1051 * @program: rpc program to set
1052 * @vers: rpc program version
1053 *
1054 * Clones the rpc client and sets up a new RPC program. This is mainly
1055 * of use for enabling different RPC programs to share the same transport.
1056 * The Sun NFSv2/v3 ACL protocol can do this.
1057 */
1058 struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
1059 const struct rpc_program *program,
1060 u32 vers)
1061 {
1062 struct rpc_create_args args = {
1063 .program = program,
1064 .prognumber = program->number,
1065 .version = vers,
1066 .authflavor = old->cl_auth->au_flavor,
1067 .cred = old->cl_cred,
1068 .stats = old->cl_stats,
1069 .timeout = old->cl_timeout,
1070 };
1071 struct rpc_clnt *clnt;
1072 int err;
1073
1074 clnt = __rpc_clone_client(&args, old);
1075 if (IS_ERR(clnt))
1076 goto out;
1077 err = rpc_ping(clnt);
1078 if (err != 0) {
1079 rpc_shutdown_client(clnt);
1080 clnt = ERR_PTR(err);
1081 }
1082 out:
1083 return clnt;
1084 }
1085 EXPORT_SYMBOL_GPL(rpc_bind_new_program);
1086
1087 struct rpc_xprt *
1088 rpc_task_get_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1089 {
1090 struct rpc_xprt_switch *xps;
1091
1092 if (!xprt)
1093 return NULL;
1094 rcu_read_lock();
1095 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1096 atomic_long_inc(&xps->xps_queuelen);
1097 rcu_read_unlock();
1098 atomic_long_inc(&xprt->queuelen);
1099
1100 return xprt;
1101 }
1102
1103 static void
1104 rpc_task_release_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
1105 {
1106 struct rpc_xprt_switch *xps;
1107
1108 atomic_long_dec(&xprt->queuelen);
1109 rcu_read_lock();
1110 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
1111 atomic_long_dec(&xps->xps_queuelen);
1112 rcu_read_unlock();
1113
1114 xprt_put(xprt);
1115 }
1116
1117 void rpc_task_release_transport(struct rpc_task *task)
1118 {
1119 struct rpc_xprt *xprt = task->tk_xprt;
1120
1121 if (xprt) {
1122 task->tk_xprt = NULL;
1123 if (task->tk_client)
1124 rpc_task_release_xprt(task->tk_client, xprt);
1125 else
1126 xprt_put(xprt);
1127 }
1128 }
1129 EXPORT_SYMBOL_GPL(rpc_task_release_transport);
1130
1131 void rpc_task_release_client(struct rpc_task *task)
1132 {
1133 struct rpc_clnt *clnt = task->tk_client;
1134
1135 rpc_task_release_transport(task);
1136 if (clnt != NULL) {
1137 /* Remove from client task list */
1138 spin_lock(&clnt->cl_lock);
1139 list_del(&task->tk_task);
1140 spin_unlock(&clnt->cl_lock);
1141 task->tk_client = NULL;
1142
1143 rpc_release_client(clnt);
1144 }
1145 }
1146
1147 static struct rpc_xprt *
1148 rpc_task_get_first_xprt(struct rpc_clnt *clnt)
1149 {
1150 struct rpc_xprt *xprt;
1151
1152 rcu_read_lock();
1153 xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
1154 rcu_read_unlock();
1155 return rpc_task_get_xprt(clnt, xprt);
1156 }
1157
1158 static struct rpc_xprt *
1159 rpc_task_get_next_xprt(struct rpc_clnt *clnt)
1160 {
1161 return rpc_task_get_xprt(clnt, xprt_iter_get_next(&clnt->cl_xpi));
1162 }
1163
1164 static
1165 void rpc_task_set_transport(struct rpc_task *task, struct rpc_clnt *clnt)
1166 {
1167 if (task->tk_xprt) {
1168 if (!(test_bit(XPRT_OFFLINE, &task->tk_xprt->state) &&
1169 (task->tk_flags & RPC_TASK_MOVEABLE)))
1170 return;
1171 xprt_release(task);
1172 xprt_put(task->tk_xprt);
1173 }
1174 if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
1175 task->tk_xprt = rpc_task_get_first_xprt(clnt);
1176 else
1177 task->tk_xprt = rpc_task_get_next_xprt(clnt);
1178 }
1179
1180 static
1181 void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
1182 {
1183 rpc_task_set_transport(task, clnt);
1184 task->tk_client = clnt;
1185 refcount_inc(&clnt->cl_count);
1186 if (clnt->cl_softrtry)
1187 task->tk_flags |= RPC_TASK_SOFT;
1188 if (clnt->cl_softerr)
1189 task->tk_flags |= RPC_TASK_TIMEOUT;
1190 if (clnt->cl_noretranstimeo)
1191 task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
1192 /* Add to the client's list of all tasks */
1193 spin_lock(&clnt->cl_lock);
1194 list_add_tail(&task->tk_task, &clnt->cl_tasks);
1195 spin_unlock(&clnt->cl_lock);
1196 }
1197
1198 static void
1199 rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
1200 {
1201 if (msg != NULL) {
1202 task->tk_msg.rpc_proc = msg->rpc_proc;
1203 task->tk_msg.rpc_argp = msg->rpc_argp;
1204 task->tk_msg.rpc_resp = msg->rpc_resp;
1205 task->tk_msg.rpc_cred = msg->rpc_cred;
1206 if (!(task->tk_flags & RPC_TASK_CRED_NOREF))
1207 get_cred(task->tk_msg.rpc_cred);
1208 }
1209 }
1210
1211 /*
1212 * Default callback for async RPC calls
1213 */
1214 static void
1215 rpc_default_callback(struct rpc_task *task, void *data)
1216 {
1217 }
1218
1219 static const struct rpc_call_ops rpc_default_ops = {
1220 .rpc_call_done = rpc_default_callback,
1221 };
1222
1223 /**
1224 * rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
1225 * @task_setup_data: pointer to task initialisation data
1226 */
1227 struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
1228 {
1229 struct rpc_task *task;
1230
1231 task = rpc_new_task(task_setup_data);
1232 if (IS_ERR(task))
1233 return task;
1234
1235 if (!RPC_IS_ASYNC(task))
1236 task->tk_flags |= RPC_TASK_CRED_NOREF;
1237
1238 rpc_task_set_client(task, task_setup_data->rpc_client);
1239 rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
1240
1241 if (task->tk_action == NULL)
1242 rpc_call_start(task);
1243
1244 atomic_inc(&task->tk_count);
1245 rpc_execute(task);
1246 return task;
1247 }
1248 EXPORT_SYMBOL_GPL(rpc_run_task);
1249
1250 /**
1251 * rpc_call_sync - Perform a synchronous RPC call
1252 * @clnt: pointer to RPC client
1253 * @msg: RPC call parameters
1254 * @flags: RPC call flags
1255 */
1256 int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
1257 {
1258 struct rpc_task *task;
1259 struct rpc_task_setup task_setup_data = {
1260 .rpc_client = clnt,
1261 .rpc_message = msg,
1262 .callback_ops = &rpc_default_ops,
1263 .flags = flags,
1264 };
1265 int status;
1266
1267 WARN_ON_ONCE(flags & RPC_TASK_ASYNC);
1268 if (flags & RPC_TASK_ASYNC) {
1269 rpc_release_calldata(task_setup_data.callback_ops,
1270 task_setup_data.callback_data);
1271 return -EINVAL;
1272 }
1273
1274 task = rpc_run_task(&task_setup_data);
1275 if (IS_ERR(task))
1276 return PTR_ERR(task);
1277 status = task->tk_status;
1278 rpc_put_task(task);
1279 return status;
1280 }
1281 EXPORT_SYMBOL_GPL(rpc_call_sync);
1282
1283 /**
1284 * rpc_call_async - Perform an asynchronous RPC call
1285 * @clnt: pointer to RPC client
1286 * @msg: RPC call parameters
1287 * @flags: RPC call flags
1288 * @tk_ops: RPC call ops
1289 * @data: user call data
1290 */
1291 int
1292 rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
1293 const struct rpc_call_ops *tk_ops, void *data)
1294 {
1295 struct rpc_task *task;
1296 struct rpc_task_setup task_setup_data = {
1297 .rpc_client = clnt,
1298 .rpc_message = msg,
1299 .callback_ops = tk_ops,
1300 .callback_data = data,
1301 .flags = flags|RPC_TASK_ASYNC,
1302 };
1303
1304 task = rpc_run_task(&task_setup_data);
1305 if (IS_ERR(task))
1306 return PTR_ERR(task);
1307 rpc_put_task(task);
1308 return 0;
1309 }
1310 EXPORT_SYMBOL_GPL(rpc_call_async);
1311
1312 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
1313 static void call_bc_encode(struct rpc_task *task);
1314
1315 /**
1316 * rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
1317 * rpc_execute against it
1318 * @req: RPC request
1319 * @timeout: timeout values to use for this task
1320 */
1321 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
1322 struct rpc_timeout *timeout)
1323 {
1324 struct rpc_task *task;
1325 struct rpc_task_setup task_setup_data = {
1326 .callback_ops = &rpc_default_ops,
1327 .flags = RPC_TASK_SOFTCONN |
1328 RPC_TASK_NO_RETRANS_TIMEOUT,
1329 };
1330
1331 dprintk("RPC: rpc_run_bc_task req= %p\n", req);
1332 /*
1333 * Create an rpc_task to send the data
1334 */
1335 task = rpc_new_task(&task_setup_data);
1336 if (IS_ERR(task)) {
1337 xprt_free_bc_request(req);
1338 return task;
1339 }
1340
1341 xprt_init_bc_request(req, task, timeout);
1342
1343 task->tk_action = call_bc_encode;
1344 atomic_inc(&task->tk_count);
1345 WARN_ON_ONCE(atomic_read(&task->tk_count) != 2);
1346 rpc_execute(task);
1347
1348 dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
1349 return task;
1350 }
1351 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
1352
1353 /**
1354 * rpc_prepare_reply_pages - Prepare to receive a reply data payload into pages
1355 * @req: RPC request to prepare
1356 * @pages: vector of struct page pointers
1357 * @base: offset in first page where receive should start, in bytes
1358 * @len: expected size of the upper layer data payload, in bytes
1359 * @hdrsize: expected size of upper layer reply header, in XDR words
1360 *
1361 */
1362 void rpc_prepare_reply_pages(struct rpc_rqst *req, struct page **pages,
1363 unsigned int base, unsigned int len,
1364 unsigned int hdrsize)
1365 {
1366 hdrsize += RPC_REPHDRSIZE + req->rq_cred->cr_auth->au_ralign;
1367
1368 xdr_inline_pages(&req->rq_rcv_buf, hdrsize << 2, pages, base, len);
1369 trace_rpc_xdr_reply_pages(req->rq_task, &req->rq_rcv_buf);
1370 }
1371 EXPORT_SYMBOL_GPL(rpc_prepare_reply_pages);
1372
1373 void
1374 rpc_call_start(struct rpc_task *task)
1375 {
1376 task->tk_action = call_start;
1377 }
1378 EXPORT_SYMBOL_GPL(rpc_call_start);
1379
1380 /**
1381 * rpc_peeraddr - extract remote peer address from clnt's xprt
1382 * @clnt: RPC client structure
1383 * @buf: target buffer
1384 * @bufsize: length of target buffer
1385 *
1386 * Returns the number of bytes that are actually in the stored address.
1387 */
1388 size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
1389 {
1390 size_t bytes;
1391 struct rpc_xprt *xprt;
1392
1393 rcu_read_lock();
1394 xprt = rcu_dereference(clnt->cl_xprt);
1395
1396 bytes = xprt->addrlen;
1397 if (bytes > bufsize)
1398 bytes = bufsize;
1399 memcpy(buf, &xprt->addr, bytes);
1400 rcu_read_unlock();
1401
1402 return bytes;
1403 }
1404 EXPORT_SYMBOL_GPL(rpc_peeraddr);
1405
1406 /**
1407 * rpc_peeraddr2str - return remote peer address in printable format
1408 * @clnt: RPC client structure
1409 * @format: address format
1410 *
1411 * NB: the lifetime of the memory referenced by the returned pointer is
1412 * the same as the rpc_xprt itself. As long as the caller uses this
1413 * pointer, it must hold the RCU read lock.
1414 */
1415 const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
1416 enum rpc_display_format_t format)
1417 {
1418 struct rpc_xprt *xprt;
1419
1420 xprt = rcu_dereference(clnt->cl_xprt);
1421
1422 if (xprt->address_strings[format] != NULL)
1423 return xprt->address_strings[format];
1424 else
1425 return "unprintable";
1426 }
1427 EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
1428
1429 static const struct sockaddr_in rpc_inaddr_loopback = {
1430 .sin_family = AF_INET,
1431 .sin_addr.s_addr = htonl(INADDR_ANY),
1432 };
1433
1434 static const struct sockaddr_in6 rpc_in6addr_loopback = {
1435 .sin6_family = AF_INET6,
1436 .sin6_addr = IN6ADDR_ANY_INIT,
1437 };
1438
1439 /*
1440 * Try a getsockname() on a connected datagram socket. Using a
1441 * connected datagram socket prevents leaving a socket in TIME_WAIT.
1442 * This conserves the ephemeral port number space.
1443 *
1444 * Returns zero and fills in "buf" if successful; otherwise, a
1445 * negative errno is returned.
1446 */
1447 static int rpc_sockname(struct net *net, struct sockaddr *sap, size_t salen,
1448 struct sockaddr *buf)
1449 {
1450 struct socket *sock;
1451 int err;
1452
1453 err = __sock_create(net, sap->sa_family,
1454 SOCK_DGRAM, IPPROTO_UDP, &sock, 1);
1455 if (err < 0) {
1456 dprintk("RPC: can't create UDP socket (%d)\n", err);
1457 goto out;
1458 }
1459
1460 switch (sap->sa_family) {
1461 case AF_INET:
1462 err = kernel_bind(sock,
1463 (struct sockaddr *)&rpc_inaddr_loopback,
1464 sizeof(rpc_inaddr_loopback));
1465 break;
1466 case AF_INET6:
1467 err = kernel_bind(sock,
1468 (struct sockaddr *)&rpc_in6addr_loopback,
1469 sizeof(rpc_in6addr_loopback));
1470 break;
1471 default:
1472 err = -EAFNOSUPPORT;
1473 goto out_release;
1474 }
1475 if (err < 0) {
1476 dprintk("RPC: can't bind UDP socket (%d)\n", err);
1477 goto out_release;
1478 }
1479
1480 err = kernel_connect(sock, sap, salen, 0);
1481 if (err < 0) {
1482 dprintk("RPC: can't connect UDP socket (%d)\n", err);
1483 goto out_release;
1484 }
1485
1486 err = kernel_getsockname(sock, buf);
1487 if (err < 0) {
1488 dprintk("RPC: getsockname failed (%d)\n", err);
1489 goto out_release;
1490 }
1491
1492 err = 0;
1493 if (buf->sa_family == AF_INET6) {
1494 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)buf;
1495 sin6->sin6_scope_id = 0;
1496 }
1497 dprintk("RPC: %s succeeded\n", __func__);
1498
1499 out_release:
1500 sock_release(sock);
1501 out:
1502 return err;
1503 }
1504
1505 /*
1506 * Scraping a connected socket failed, so we don't have a useable
1507 * local address. Fallback: generate an address that will prevent
1508 * the server from calling us back.
1509 *
1510 * Returns zero and fills in "buf" if successful; otherwise, a
1511 * negative errno is returned.
1512 */
1513 static int rpc_anyaddr(int family, struct sockaddr *buf, size_t buflen)
1514 {
1515 switch (family) {
1516 case AF_INET:
1517 if (buflen < sizeof(rpc_inaddr_loopback))
1518 return -EINVAL;
1519 memcpy(buf, &rpc_inaddr_loopback,
1520 sizeof(rpc_inaddr_loopback));
1521 break;
1522 case AF_INET6:
1523 if (buflen < sizeof(rpc_in6addr_loopback))
1524 return -EINVAL;
1525 memcpy(buf, &rpc_in6addr_loopback,
1526 sizeof(rpc_in6addr_loopback));
1527 break;
1528 default:
1529 dprintk("RPC: %s: address family not supported\n",
1530 __func__);
1531 return -EAFNOSUPPORT;
1532 }
1533 dprintk("RPC: %s: succeeded\n", __func__);
1534 return 0;
1535 }
1536
1537 /**
1538 * rpc_localaddr - discover local endpoint address for an RPC client
1539 * @clnt: RPC client structure
1540 * @buf: target buffer
1541 * @buflen: size of target buffer, in bytes
1542 *
1543 * Returns zero and fills in "buf" and "buflen" if successful;
1544 * otherwise, a negative errno is returned.
1545 *
1546 * This works even if the underlying transport is not currently connected,
1547 * or if the upper layer never previously provided a source address.
1548 *
1549 * The result of this function call is transient: multiple calls in
1550 * succession may give different results, depending on how local
1551 * networking configuration changes over time.
1552 */
1553 int rpc_localaddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t buflen)
1554 {
1555 struct sockaddr_storage address;
1556 struct sockaddr *sap = (struct sockaddr *)&address;
1557 struct rpc_xprt *xprt;
1558 struct net *net;
1559 size_t salen;
1560 int err;
1561
1562 rcu_read_lock();
1563 xprt = rcu_dereference(clnt->cl_xprt);
1564 salen = xprt->addrlen;
1565 memcpy(sap, &xprt->addr, salen);
1566 net = get_net(xprt->xprt_net);
1567 rcu_read_unlock();
1568
1569 rpc_set_port(sap, 0);
1570 err = rpc_sockname(net, sap, salen, buf);
1571 put_net(net);
1572 if (err != 0)
1573 /* Couldn't discover local address, return ANYADDR */
1574 return rpc_anyaddr(sap->sa_family, buf, buflen);
1575 return 0;
1576 }
1577 EXPORT_SYMBOL_GPL(rpc_localaddr);
1578
1579 void
1580 rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
1581 {
1582 struct rpc_xprt *xprt;
1583
1584 rcu_read_lock();
1585 xprt = rcu_dereference(clnt->cl_xprt);
1586 if (xprt->ops->set_buffer_size)
1587 xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
1588 rcu_read_unlock();
1589 }
1590 EXPORT_SYMBOL_GPL(rpc_setbufsize);
1591
1592 /**
1593 * rpc_net_ns - Get the network namespace for this RPC client
1594 * @clnt: RPC client to query
1595 *
1596 */
1597 struct net *rpc_net_ns(struct rpc_clnt *clnt)
1598 {
1599 struct net *ret;
1600
1601 rcu_read_lock();
1602 ret = rcu_dereference(clnt->cl_xprt)->xprt_net;
1603 rcu_read_unlock();
1604 return ret;
1605 }
1606 EXPORT_SYMBOL_GPL(rpc_net_ns);
1607
1608 /**
1609 * rpc_max_payload - Get maximum payload size for a transport, in bytes
1610 * @clnt: RPC client to query
1611 *
1612 * For stream transports, this is one RPC record fragment (see RFC
1613 * 1831), as we don't support multi-record requests yet. For datagram
1614 * transports, this is the size of an IP packet minus the IP, UDP, and
1615 * RPC header sizes.
1616 */
1617 size_t rpc_max_payload(struct rpc_clnt *clnt)
1618 {
1619 size_t ret;
1620
1621 rcu_read_lock();
1622 ret = rcu_dereference(clnt->cl_xprt)->max_payload;
1623 rcu_read_unlock();
1624 return ret;
1625 }
1626 EXPORT_SYMBOL_GPL(rpc_max_payload);
1627
1628 /**
1629 * rpc_max_bc_payload - Get maximum backchannel payload size, in bytes
1630 * @clnt: RPC client to query
1631 */
1632 size_t rpc_max_bc_payload(struct rpc_clnt *clnt)
1633 {
1634 struct rpc_xprt *xprt;
1635 size_t ret;
1636
1637 rcu_read_lock();
1638 xprt = rcu_dereference(clnt->cl_xprt);
1639 ret = xprt->ops->bc_maxpayload(xprt);
1640 rcu_read_unlock();
1641 return ret;
1642 }
1643 EXPORT_SYMBOL_GPL(rpc_max_bc_payload);
1644
1645 unsigned int rpc_num_bc_slots(struct rpc_clnt *clnt)
1646 {
1647 struct rpc_xprt *xprt;
1648 unsigned int ret;
1649
1650 rcu_read_lock();
1651 xprt = rcu_dereference(clnt->cl_xprt);
1652 ret = xprt->ops->bc_num_slots(xprt);
1653 rcu_read_unlock();
1654 return ret;
1655 }
1656 EXPORT_SYMBOL_GPL(rpc_num_bc_slots);
1657
1658 /**
1659 * rpc_force_rebind - force transport to check that remote port is unchanged
1660 * @clnt: client to rebind
1661 *
1662 */
1663 void rpc_force_rebind(struct rpc_clnt *clnt)
1664 {
1665 if (clnt->cl_autobind) {
1666 rcu_read_lock();
1667 xprt_clear_bound(rcu_dereference(clnt->cl_xprt));
1668 rcu_read_unlock();
1669 }
1670 }
1671 EXPORT_SYMBOL_GPL(rpc_force_rebind);
1672
1673 static int
1674 __rpc_restart_call(struct rpc_task *task, void (*action)(struct rpc_task *))
1675 {
1676 task->tk_status = 0;
1677 task->tk_rpc_status = 0;
1678 task->tk_action = action;
1679 return 1;
1680 }
1681
1682 /*
1683 * Restart an (async) RPC call. Usually called from within the
1684 * exit handler.
1685 */
1686 int
1687 rpc_restart_call(struct rpc_task *task)
1688 {
1689 return __rpc_restart_call(task, call_start);
1690 }
1691 EXPORT_SYMBOL_GPL(rpc_restart_call);
1692
1693 /*
1694 * Restart an (async) RPC call from the call_prepare state.
1695 * Usually called from within the exit handler.
1696 */
1697 int
1698 rpc_restart_call_prepare(struct rpc_task *task)
1699 {
1700 if (task->tk_ops->rpc_call_prepare != NULL)
1701 return __rpc_restart_call(task, rpc_prepare_task);
1702 return rpc_restart_call(task);
1703 }
1704 EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
1705
1706 const char
1707 *rpc_proc_name(const struct rpc_task *task)
1708 {
1709 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1710
1711 if (proc) {
1712 if (proc->p_name)
1713 return proc->p_name;
1714 else
1715 return "NULL";
1716 } else
1717 return "no proc";
1718 }
1719
1720 static void
1721 __rpc_call_rpcerror(struct rpc_task *task, int tk_status, int rpc_status)
1722 {
1723 trace_rpc_call_rpcerror(task, tk_status, rpc_status);
1724 rpc_task_set_rpc_status(task, rpc_status);
1725 rpc_exit(task, tk_status);
1726 }
1727
1728 static void
1729 rpc_call_rpcerror(struct rpc_task *task, int status)
1730 {
1731 __rpc_call_rpcerror(task, status, status);
1732 }
1733
1734 /*
1735 * 0. Initial state
1736 *
1737 * Other FSM states can be visited zero or more times, but
1738 * this state is visited exactly once for each RPC.
1739 */
1740 static void
1741 call_start(struct rpc_task *task)
1742 {
1743 struct rpc_clnt *clnt = task->tk_client;
1744 int idx = task->tk_msg.rpc_proc->p_statidx;
1745
1746 trace_rpc_request(task);
1747
1748 if (task->tk_client->cl_shutdown) {
1749 rpc_call_rpcerror(task, -EIO);
1750 return;
1751 }
1752
1753 /* Increment call count (version might not be valid for ping) */
1754 if (clnt->cl_program->version[clnt->cl_vers])
1755 clnt->cl_program->version[clnt->cl_vers]->counts[idx]++;
1756 clnt->cl_stats->rpccnt++;
1757 task->tk_action = call_reserve;
1758 rpc_task_set_transport(task, clnt);
1759 }
1760
1761 /*
1762 * 1. Reserve an RPC call slot
1763 */
1764 static void
1765 call_reserve(struct rpc_task *task)
1766 {
1767 task->tk_status = 0;
1768 task->tk_action = call_reserveresult;
1769 xprt_reserve(task);
1770 }
1771
1772 static void call_retry_reserve(struct rpc_task *task);
1773
1774 /*
1775 * 1b. Grok the result of xprt_reserve()
1776 */
1777 static void
1778 call_reserveresult(struct rpc_task *task)
1779 {
1780 int status = task->tk_status;
1781
1782 /*
1783 * After a call to xprt_reserve(), we must have either
1784 * a request slot or else an error status.
1785 */
1786 task->tk_status = 0;
1787 if (status >= 0) {
1788 if (task->tk_rqstp) {
1789 task->tk_action = call_refresh;
1790 return;
1791 }
1792
1793 rpc_call_rpcerror(task, -EIO);
1794 return;
1795 }
1796
1797 switch (status) {
1798 case -ENOMEM:
1799 rpc_delay(task, HZ >> 2);
1800 fallthrough;
1801 case -EAGAIN: /* woken up; retry */
1802 task->tk_action = call_retry_reserve;
1803 return;
1804 default:
1805 rpc_call_rpcerror(task, status);
1806 }
1807 }
1808
1809 /*
1810 * 1c. Retry reserving an RPC call slot
1811 */
1812 static void
1813 call_retry_reserve(struct rpc_task *task)
1814 {
1815 task->tk_status = 0;
1816 task->tk_action = call_reserveresult;
1817 xprt_retry_reserve(task);
1818 }
1819
1820 /*
1821 * 2. Bind and/or refresh the credentials
1822 */
1823 static void
1824 call_refresh(struct rpc_task *task)
1825 {
1826 task->tk_action = call_refreshresult;
1827 task->tk_status = 0;
1828 task->tk_client->cl_stats->rpcauthrefresh++;
1829 rpcauth_refreshcred(task);
1830 }
1831
1832 /*
1833 * 2a. Process the results of a credential refresh
1834 */
1835 static void
1836 call_refreshresult(struct rpc_task *task)
1837 {
1838 int status = task->tk_status;
1839
1840 task->tk_status = 0;
1841 task->tk_action = call_refresh;
1842 switch (status) {
1843 case 0:
1844 if (rpcauth_uptodatecred(task)) {
1845 task->tk_action = call_allocate;
1846 return;
1847 }
1848 /* Use rate-limiting and a max number of retries if refresh
1849 * had status 0 but failed to update the cred.
1850 */
1851 fallthrough;
1852 case -ETIMEDOUT:
1853 rpc_delay(task, 3*HZ);
1854 fallthrough;
1855 case -EAGAIN:
1856 status = -EACCES;
1857 fallthrough;
1858 case -EKEYEXPIRED:
1859 if (!task->tk_cred_retry)
1860 break;
1861 task->tk_cred_retry--;
1862 trace_rpc_retry_refresh_status(task);
1863 return;
1864 case -ENOMEM:
1865 rpc_delay(task, HZ >> 4);
1866 return;
1867 }
1868 trace_rpc_refresh_status(task);
1869 rpc_call_rpcerror(task, status);
1870 }
1871
1872 /*
1873 * 2b. Allocate the buffer. For details, see sched.c:rpc_malloc.
1874 * (Note: buffer memory is freed in xprt_release).
1875 */
1876 static void
1877 call_allocate(struct rpc_task *task)
1878 {
1879 const struct rpc_auth *auth = task->tk_rqstp->rq_cred->cr_auth;
1880 struct rpc_rqst *req = task->tk_rqstp;
1881 struct rpc_xprt *xprt = req->rq_xprt;
1882 const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
1883 int status;
1884
1885 task->tk_status = 0;
1886 task->tk_action = call_encode;
1887
1888 if (req->rq_buffer)
1889 return;
1890
1891 /*
1892 * Calculate the size (in quads) of the RPC call
1893 * and reply headers, and convert both values
1894 * to byte sizes.
1895 */
1896 req->rq_callsize = RPC_CALLHDRSIZE + (auth->au_cslack << 1) +
1897 proc->p_arglen;
1898 req->rq_callsize <<= 2;
1899 /*
1900 * Note: the reply buffer must at minimum allocate enough space
1901 * for the 'struct accepted_reply' from RFC5531.
1902 */
1903 req->rq_rcvsize = RPC_REPHDRSIZE + auth->au_rslack + \
1904 max_t(size_t, proc->p_replen, 2);
1905 req->rq_rcvsize <<= 2;
1906
1907 status = xprt->ops->buf_alloc(task);
1908 trace_rpc_buf_alloc(task, status);
1909 if (status == 0)
1910 return;
1911 if (status != -ENOMEM) {
1912 rpc_call_rpcerror(task, status);
1913 return;
1914 }
1915
1916 if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
1917 task->tk_action = call_allocate;
1918 rpc_delay(task, HZ>>4);
1919 return;
1920 }
1921
1922 rpc_call_rpcerror(task, -ERESTARTSYS);
1923 }
1924
1925 static int
1926 rpc_task_need_encode(struct rpc_task *task)
1927 {
1928 return test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate) == 0 &&
1929 (!(task->tk_flags & RPC_TASK_SENT) ||
1930 !(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) ||
1931 xprt_request_need_retransmit(task));
1932 }
1933
1934 static void
1935 rpc_xdr_encode(struct rpc_task *task)
1936 {
1937 struct rpc_rqst *req = task->tk_rqstp;
1938 struct xdr_stream xdr;
1939
1940 xdr_buf_init(&req->rq_snd_buf,
1941 req->rq_buffer,
1942 req->rq_callsize);
1943 xdr_buf_init(&req->rq_rcv_buf,
1944 req->rq_rbuffer,
1945 req->rq_rcvsize);
1946
1947 req->rq_reply_bytes_recvd = 0;
1948 req->rq_snd_buf.head[0].iov_len = 0;
1949 xdr_init_encode(&xdr, &req->rq_snd_buf,
1950 req->rq_snd_buf.head[0].iov_base, req);
1951 if (rpc_encode_header(task, &xdr))
1952 return;
1953
1954 task->tk_status = rpcauth_wrap_req(task, &xdr);
1955 }
1956
1957 /*
1958 * 3. Encode arguments of an RPC call
1959 */
1960 static void
1961 call_encode(struct rpc_task *task)
1962 {
1963 if (!rpc_task_need_encode(task))
1964 goto out;
1965
1966 /* Dequeue task from the receive queue while we're encoding */
1967 xprt_request_dequeue_xprt(task);
1968 /* Encode here so that rpcsec_gss can use correct sequence number. */
1969 rpc_xdr_encode(task);
1970 /* Add task to reply queue before transmission to avoid races */
1971 if (task->tk_status == 0 && rpc_reply_expected(task))
1972 task->tk_status = xprt_request_enqueue_receive(task);
1973 /* Did the encode result in an error condition? */
1974 if (task->tk_status != 0) {
1975 /* Was the error nonfatal? */
1976 switch (task->tk_status) {
1977 case -EAGAIN:
1978 case -ENOMEM:
1979 rpc_delay(task, HZ >> 4);
1980 break;
1981 case -EKEYEXPIRED:
1982 if (!task->tk_cred_retry) {
1983 rpc_call_rpcerror(task, task->tk_status);
1984 } else {
1985 task->tk_action = call_refresh;
1986 task->tk_cred_retry--;
1987 trace_rpc_retry_refresh_status(task);
1988 }
1989 break;
1990 default:
1991 rpc_call_rpcerror(task, task->tk_status);
1992 }
1993 return;
1994 }
1995
1996 xprt_request_enqueue_transmit(task);
1997 out:
1998 task->tk_action = call_transmit;
1999 /* Check that the connection is OK */
2000 if (!xprt_bound(task->tk_xprt))
2001 task->tk_action = call_bind;
2002 else if (!xprt_connected(task->tk_xprt))
2003 task->tk_action = call_connect;
2004 }
2005
2006 /*
2007 * Helpers to check if the task was already transmitted, and
2008 * to take action when that is the case.
2009 */
2010 static bool
2011 rpc_task_transmitted(struct rpc_task *task)
2012 {
2013 return !test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate);
2014 }
2015
2016 static void
2017 rpc_task_handle_transmitted(struct rpc_task *task)
2018 {
2019 xprt_end_transmit(task);
2020 task->tk_action = call_transmit_status;
2021 }
2022
2023 /*
2024 * 4. Get the server port number if not yet set
2025 */
2026 static void
2027 call_bind(struct rpc_task *task)
2028 {
2029 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2030
2031 if (rpc_task_transmitted(task)) {
2032 rpc_task_handle_transmitted(task);
2033 return;
2034 }
2035
2036 if (xprt_bound(xprt)) {
2037 task->tk_action = call_connect;
2038 return;
2039 }
2040
2041 task->tk_action = call_bind_status;
2042 if (!xprt_prepare_transmit(task))
2043 return;
2044
2045 xprt->ops->rpcbind(task);
2046 }
2047
2048 /*
2049 * 4a. Sort out bind result
2050 */
2051 static void
2052 call_bind_status(struct rpc_task *task)
2053 {
2054 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2055 int status = -EIO;
2056
2057 if (rpc_task_transmitted(task)) {
2058 rpc_task_handle_transmitted(task);
2059 return;
2060 }
2061
2062 if (task->tk_status >= 0)
2063 goto out_next;
2064 if (xprt_bound(xprt)) {
2065 task->tk_status = 0;
2066 goto out_next;
2067 }
2068
2069 switch (task->tk_status) {
2070 case -ENOMEM:
2071 rpc_delay(task, HZ >> 2);
2072 goto retry_timeout;
2073 case -EACCES:
2074 trace_rpcb_prog_unavail_err(task);
2075 /* fail immediately if this is an RPC ping */
2076 if (task->tk_msg.rpc_proc->p_proc == 0) {
2077 status = -EOPNOTSUPP;
2078 break;
2079 }
2080 rpc_delay(task, 3*HZ);
2081 goto retry_timeout;
2082 case -ENOBUFS:
2083 rpc_delay(task, HZ >> 2);
2084 goto retry_timeout;
2085 case -EAGAIN:
2086 goto retry_timeout;
2087 case -ETIMEDOUT:
2088 trace_rpcb_timeout_err(task);
2089 goto retry_timeout;
2090 case -EPFNOSUPPORT:
2091 /* server doesn't support any rpcbind version we know of */
2092 trace_rpcb_bind_version_err(task);
2093 break;
2094 case -EPROTONOSUPPORT:
2095 trace_rpcb_bind_version_err(task);
2096 goto retry_timeout;
2097 case -ECONNREFUSED: /* connection problems */
2098 case -ECONNRESET:
2099 case -ECONNABORTED:
2100 case -ENOTCONN:
2101 case -EHOSTDOWN:
2102 case -ENETDOWN:
2103 case -EHOSTUNREACH:
2104 case -ENETUNREACH:
2105 case -EPIPE:
2106 trace_rpcb_unreachable_err(task);
2107 if (!RPC_IS_SOFTCONN(task)) {
2108 rpc_delay(task, 5*HZ);
2109 goto retry_timeout;
2110 }
2111 status = task->tk_status;
2112 break;
2113 default:
2114 trace_rpcb_unrecognized_err(task);
2115 }
2116
2117 rpc_call_rpcerror(task, status);
2118 return;
2119 out_next:
2120 task->tk_action = call_connect;
2121 return;
2122 retry_timeout:
2123 task->tk_status = 0;
2124 task->tk_action = call_bind;
2125 rpc_check_timeout(task);
2126 }
2127
2128 /*
2129 * 4b. Connect to the RPC server
2130 */
2131 static void
2132 call_connect(struct rpc_task *task)
2133 {
2134 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2135
2136 if (rpc_task_transmitted(task)) {
2137 rpc_task_handle_transmitted(task);
2138 return;
2139 }
2140
2141 if (xprt_connected(xprt)) {
2142 task->tk_action = call_transmit;
2143 return;
2144 }
2145
2146 task->tk_action = call_connect_status;
2147 if (task->tk_status < 0)
2148 return;
2149 if (task->tk_flags & RPC_TASK_NOCONNECT) {
2150 rpc_call_rpcerror(task, -ENOTCONN);
2151 return;
2152 }
2153 if (!xprt_prepare_transmit(task))
2154 return;
2155 xprt_connect(task);
2156 }
2157
2158 /*
2159 * 4c. Sort out connect result
2160 */
2161 static void
2162 call_connect_status(struct rpc_task *task)
2163 {
2164 struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt;
2165 struct rpc_clnt *clnt = task->tk_client;
2166 int status = task->tk_status;
2167
2168 if (rpc_task_transmitted(task)) {
2169 rpc_task_handle_transmitted(task);
2170 return;
2171 }
2172
2173 trace_rpc_connect_status(task);
2174
2175 if (task->tk_status == 0) {
2176 clnt->cl_stats->netreconn++;
2177 goto out_next;
2178 }
2179 if (xprt_connected(xprt)) {
2180 task->tk_status = 0;
2181 goto out_next;
2182 }
2183
2184 task->tk_status = 0;
2185 switch (status) {
2186 case -ECONNREFUSED:
2187 case -ECONNRESET:
2188 /* A positive refusal suggests a rebind is needed. */
2189 if (RPC_IS_SOFTCONN(task))
2190 break;
2191 if (clnt->cl_autobind) {
2192 rpc_force_rebind(clnt);
2193 goto out_retry;
2194 }
2195 fallthrough;
2196 case -ECONNABORTED:
2197 case -ENETDOWN:
2198 case -ENETUNREACH:
2199 case -EHOSTUNREACH:
2200 case -EPIPE:
2201 case -EPROTO:
2202 xprt_conditional_disconnect(task->tk_rqstp->rq_xprt,
2203 task->tk_rqstp->rq_connect_cookie);
2204 if (RPC_IS_SOFTCONN(task))
2205 break;
2206 /* retry with existing socket, after a delay */
2207 rpc_delay(task, 3*HZ);
2208 fallthrough;
2209 case -EADDRINUSE:
2210 case -ENOTCONN:
2211 case -EAGAIN:
2212 case -ETIMEDOUT:
2213 if (!(task->tk_flags & RPC_TASK_NO_ROUND_ROBIN) &&
2214 (task->tk_flags & RPC_TASK_MOVEABLE) &&
2215 test_bit(XPRT_REMOVE, &xprt->state)) {
2216 struct rpc_xprt *saved = task->tk_xprt;
2217 struct rpc_xprt_switch *xps;
2218
2219 xps = rpc_clnt_xprt_switch_get(clnt);
2220 if (xps->xps_nxprts > 1) {
2221 long value;
2222
2223 xprt_release(task);
2224 value = atomic_long_dec_return(&xprt->queuelen);
2225 if (value == 0)
2226 rpc_xprt_switch_remove_xprt(xps, saved,
2227 true);
2228 xprt_put(saved);
2229 task->tk_xprt = NULL;
2230 task->tk_action = call_start;
2231 }
2232 xprt_switch_put(xps);
2233 if (!task->tk_xprt)
2234 goto out;
2235 }
2236 goto out_retry;
2237 case -ENOBUFS:
2238 rpc_delay(task, HZ >> 2);
2239 goto out_retry;
2240 }
2241 rpc_call_rpcerror(task, status);
2242 return;
2243 out_next:
2244 task->tk_action = call_transmit;
2245 return;
2246 out_retry:
2247 /* Check for timeouts before looping back to call_bind */
2248 task->tk_action = call_bind;
2249 out:
2250 rpc_check_timeout(task);
2251 }
2252
2253 /*
2254 * 5. Transmit the RPC request, and wait for reply
2255 */
2256 static void
2257 call_transmit(struct rpc_task *task)
2258 {
2259 if (rpc_task_transmitted(task)) {
2260 rpc_task_handle_transmitted(task);
2261 return;
2262 }
2263
2264 task->tk_action = call_transmit_status;
2265 if (!xprt_prepare_transmit(task))
2266 return;
2267 task->tk_status = 0;
2268 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2269 if (!xprt_connected(task->tk_xprt)) {
2270 task->tk_status = -ENOTCONN;
2271 return;
2272 }
2273 xprt_transmit(task);
2274 }
2275 xprt_end_transmit(task);
2276 }
2277
2278 /*
2279 * 5a. Handle cleanup after a transmission
2280 */
2281 static void
2282 call_transmit_status(struct rpc_task *task)
2283 {
2284 task->tk_action = call_status;
2285
2286 /*
2287 * Common case: success. Force the compiler to put this
2288 * test first.
2289 */
2290 if (rpc_task_transmitted(task)) {
2291 task->tk_status = 0;
2292 xprt_request_wait_receive(task);
2293 return;
2294 }
2295
2296 switch (task->tk_status) {
2297 default:
2298 break;
2299 case -EBADMSG:
2300 task->tk_status = 0;
2301 task->tk_action = call_encode;
2302 break;
2303 /*
2304 * Special cases: if we've been waiting on the
2305 * socket's write_space() callback, or if the
2306 * socket just returned a connection error,
2307 * then hold onto the transport lock.
2308 */
2309 case -ENOMEM:
2310 case -ENOBUFS:
2311 rpc_delay(task, HZ>>2);
2312 fallthrough;
2313 case -EBADSLT:
2314 case -EAGAIN:
2315 task->tk_action = call_transmit;
2316 task->tk_status = 0;
2317 break;
2318 case -EHOSTDOWN:
2319 case -ENETDOWN:
2320 case -EHOSTUNREACH:
2321 case -ENETUNREACH:
2322 case -EPERM:
2323 break;
2324 case -ECONNREFUSED:
2325 if (RPC_IS_SOFTCONN(task)) {
2326 if (!task->tk_msg.rpc_proc->p_proc)
2327 trace_xprt_ping(task->tk_xprt,
2328 task->tk_status);
2329 rpc_call_rpcerror(task, task->tk_status);
2330 return;
2331 }
2332 fallthrough;
2333 case -ECONNRESET:
2334 case -ECONNABORTED:
2335 case -EADDRINUSE:
2336 case -ENOTCONN:
2337 case -EPIPE:
2338 task->tk_action = call_bind;
2339 task->tk_status = 0;
2340 break;
2341 }
2342 rpc_check_timeout(task);
2343 }
2344
2345 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
2346 static void call_bc_transmit(struct rpc_task *task);
2347 static void call_bc_transmit_status(struct rpc_task *task);
2348
2349 static void
2350 call_bc_encode(struct rpc_task *task)
2351 {
2352 xprt_request_enqueue_transmit(task);
2353 task->tk_action = call_bc_transmit;
2354 }
2355
2356 /*
2357 * 5b. Send the backchannel RPC reply. On error, drop the reply. In
2358 * addition, disconnect on connectivity errors.
2359 */
2360 static void
2361 call_bc_transmit(struct rpc_task *task)
2362 {
2363 task->tk_action = call_bc_transmit_status;
2364 if (test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
2365 if (!xprt_prepare_transmit(task))
2366 return;
2367 task->tk_status = 0;
2368 xprt_transmit(task);
2369 }
2370 xprt_end_transmit(task);
2371 }
2372
2373 static void
2374 call_bc_transmit_status(struct rpc_task *task)
2375 {
2376 struct rpc_rqst *req = task->tk_rqstp;
2377
2378 if (rpc_task_transmitted(task))
2379 task->tk_status = 0;
2380
2381 switch (task->tk_status) {
2382 case 0:
2383 /* Success */
2384 case -ENETDOWN:
2385 case -EHOSTDOWN:
2386 case -EHOSTUNREACH:
2387 case -ENETUNREACH:
2388 case -ECONNRESET:
2389 case -ECONNREFUSED:
2390 case -EADDRINUSE:
2391 case -ENOTCONN:
2392 case -EPIPE:
2393 break;
2394 case -ENOMEM:
2395 case -ENOBUFS:
2396 rpc_delay(task, HZ>>2);
2397 fallthrough;
2398 case -EBADSLT:
2399 case -EAGAIN:
2400 task->tk_status = 0;
2401 task->tk_action = call_bc_transmit;
2402 return;
2403 case -ETIMEDOUT:
2404 /*
2405 * Problem reaching the server. Disconnect and let the
2406 * forechannel reestablish the connection. The server will
2407 * have to retransmit the backchannel request and we'll
2408 * reprocess it. Since these ops are idempotent, there's no
2409 * need to cache our reply at this time.
2410 */
2411 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2412 "error: %d\n", task->tk_status);
2413 xprt_conditional_disconnect(req->rq_xprt,
2414 req->rq_connect_cookie);
2415 break;
2416 default:
2417 /*
2418 * We were unable to reply and will have to drop the
2419 * request. The server should reconnect and retransmit.
2420 */
2421 printk(KERN_NOTICE "RPC: Could not send backchannel reply "
2422 "error: %d\n", task->tk_status);
2423 break;
2424 }
2425 task->tk_action = rpc_exit_task;
2426 }
2427 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
2428
2429 /*
2430 * 6. Sort out the RPC call status
2431 */
2432 static void
2433 call_status(struct rpc_task *task)
2434 {
2435 struct rpc_clnt *clnt = task->tk_client;
2436 int status;
2437
2438 if (!task->tk_msg.rpc_proc->p_proc)
2439 trace_xprt_ping(task->tk_xprt, task->tk_status);
2440
2441 status = task->tk_status;
2442 if (status >= 0) {
2443 task->tk_action = call_decode;
2444 return;
2445 }
2446
2447 trace_rpc_call_status(task);
2448 task->tk_status = 0;
2449 switch(status) {
2450 case -EHOSTDOWN:
2451 case -ENETDOWN:
2452 case -EHOSTUNREACH:
2453 case -ENETUNREACH:
2454 case -EPERM:
2455 if (RPC_IS_SOFTCONN(task))
2456 goto out_exit;
2457 /*
2458 * Delay any retries for 3 seconds, then handle as if it
2459 * were a timeout.
2460 */
2461 rpc_delay(task, 3*HZ);
2462 fallthrough;
2463 case -ETIMEDOUT:
2464 break;
2465 case -ECONNREFUSED:
2466 case -ECONNRESET:
2467 case -ECONNABORTED:
2468 case -ENOTCONN:
2469 rpc_force_rebind(clnt);
2470 break;
2471 case -EADDRINUSE:
2472 rpc_delay(task, 3*HZ);
2473 fallthrough;
2474 case -EPIPE:
2475 case -EAGAIN:
2476 break;
2477 case -ENFILE:
2478 case -ENOBUFS:
2479 case -ENOMEM:
2480 rpc_delay(task, HZ>>2);
2481 break;
2482 case -EIO:
2483 /* shutdown or soft timeout */
2484 goto out_exit;
2485 default:
2486 if (clnt->cl_chatty)
2487 printk("%s: RPC call returned error %d\n",
2488 clnt->cl_program->name, -status);
2489 goto out_exit;
2490 }
2491 task->tk_action = call_encode;
2492 rpc_check_timeout(task);
2493 return;
2494 out_exit:
2495 rpc_call_rpcerror(task, status);
2496 }
2497
2498 static bool
2499 rpc_check_connected(const struct rpc_rqst *req)
2500 {
2501 /* No allocated request or transport? return true */
2502 if (!req || !req->rq_xprt)
2503 return true;
2504 return xprt_connected(req->rq_xprt);
2505 }
2506
2507 static void
2508 rpc_check_timeout(struct rpc_task *task)
2509 {
2510 struct rpc_clnt *clnt = task->tk_client;
2511
2512 if (RPC_SIGNALLED(task))
2513 return;
2514
2515 if (xprt_adjust_timeout(task->tk_rqstp) == 0)
2516 return;
2517
2518 trace_rpc_timeout_status(task);
2519 task->tk_timeouts++;
2520
2521 if (RPC_IS_SOFTCONN(task) && !rpc_check_connected(task->tk_rqstp)) {
2522 rpc_call_rpcerror(task, -ETIMEDOUT);
2523 return;
2524 }
2525
2526 if (RPC_IS_SOFT(task)) {
2527 /*
2528 * Once a "no retrans timeout" soft tasks (a.k.a NFSv4) has
2529 * been sent, it should time out only if the transport
2530 * connection gets terminally broken.
2531 */
2532 if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) &&
2533 rpc_check_connected(task->tk_rqstp))
2534 return;
2535
2536 if (clnt->cl_chatty) {
2537 pr_notice_ratelimited(
2538 "%s: server %s not responding, timed out\n",
2539 clnt->cl_program->name,
2540 task->tk_xprt->servername);
2541 }
2542 if (task->tk_flags & RPC_TASK_TIMEOUT)
2543 rpc_call_rpcerror(task, -ETIMEDOUT);
2544 else
2545 __rpc_call_rpcerror(task, -EIO, -ETIMEDOUT);
2546 return;
2547 }
2548
2549 if (!(task->tk_flags & RPC_CALL_MAJORSEEN)) {
2550 task->tk_flags |= RPC_CALL_MAJORSEEN;
2551 if (clnt->cl_chatty) {
2552 pr_notice_ratelimited(
2553 "%s: server %s not responding, still trying\n",
2554 clnt->cl_program->name,
2555 task->tk_xprt->servername);
2556 }
2557 }
2558 rpc_force_rebind(clnt);
2559 /*
2560 * Did our request time out due to an RPCSEC_GSS out-of-sequence
2561 * event? RFC2203 requires the server to drop all such requests.
2562 */
2563 rpcauth_invalcred(task);
2564 }
2565
2566 /*
2567 * 7. Decode the RPC reply
2568 */
2569 static void
2570 call_decode(struct rpc_task *task)
2571 {
2572 struct rpc_clnt *clnt = task->tk_client;
2573 struct rpc_rqst *req = task->tk_rqstp;
2574 struct xdr_stream xdr;
2575 int err;
2576
2577 if (!task->tk_msg.rpc_proc->p_decode) {
2578 task->tk_action = rpc_exit_task;
2579 return;
2580 }
2581
2582 if (task->tk_flags & RPC_CALL_MAJORSEEN) {
2583 if (clnt->cl_chatty) {
2584 pr_notice_ratelimited("%s: server %s OK\n",
2585 clnt->cl_program->name,
2586 task->tk_xprt->servername);
2587 }
2588 task->tk_flags &= ~RPC_CALL_MAJORSEEN;
2589 }
2590
2591 /*
2592 * Did we ever call xprt_complete_rqst()? If not, we should assume
2593 * the message is incomplete.
2594 */
2595 err = -EAGAIN;
2596 if (!req->rq_reply_bytes_recvd)
2597 goto out;
2598
2599 /* Ensure that we see all writes made by xprt_complete_rqst()
2600 * before it changed req->rq_reply_bytes_recvd.
2601 */
2602 smp_rmb();
2603
2604 req->rq_rcv_buf.len = req->rq_private_buf.len;
2605 trace_rpc_xdr_recvfrom(task, &req->rq_rcv_buf);
2606
2607 /* Check that the softirq receive buffer is valid */
2608 WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
2609 sizeof(req->rq_rcv_buf)) != 0);
2610
2611 xdr_init_decode(&xdr, &req->rq_rcv_buf,
2612 req->rq_rcv_buf.head[0].iov_base, req);
2613 err = rpc_decode_header(task, &xdr);
2614 out:
2615 switch (err) {
2616 case 0:
2617 task->tk_action = rpc_exit_task;
2618 task->tk_status = rpcauth_unwrap_resp(task, &xdr);
2619 xdr_finish_decode(&xdr);
2620 return;
2621 case -EAGAIN:
2622 task->tk_status = 0;
2623 if (task->tk_client->cl_discrtry)
2624 xprt_conditional_disconnect(req->rq_xprt,
2625 req->rq_connect_cookie);
2626 task->tk_action = call_encode;
2627 rpc_check_timeout(task);
2628 break;
2629 case -EKEYREJECTED:
2630 task->tk_action = call_reserve;
2631 rpc_check_timeout(task);
2632 rpcauth_invalcred(task);
2633 /* Ensure we obtain a new XID if we retry! */
2634 xprt_release(task);
2635 }
2636 }
2637
2638 static int
2639 rpc_encode_header(struct rpc_task *task, struct xdr_stream *xdr)
2640 {
2641 struct rpc_clnt *clnt = task->tk_client;
2642 struct rpc_rqst *req = task->tk_rqstp;
2643 __be32 *p;
2644 int error;
2645
2646 error = -EMSGSIZE;
2647 p = xdr_reserve_space(xdr, RPC_CALLHDRSIZE << 2);
2648 if (!p)
2649 goto out_fail;
2650 *p++ = req->rq_xid;
2651 *p++ = rpc_call;
2652 *p++ = cpu_to_be32(RPC_VERSION);
2653 *p++ = cpu_to_be32(clnt->cl_prog);
2654 *p++ = cpu_to_be32(clnt->cl_vers);
2655 *p = cpu_to_be32(task->tk_msg.rpc_proc->p_proc);
2656
2657 error = rpcauth_marshcred(task, xdr);
2658 if (error < 0)
2659 goto out_fail;
2660 return 0;
2661 out_fail:
2662 trace_rpc_bad_callhdr(task);
2663 rpc_call_rpcerror(task, error);
2664 return error;
2665 }
2666
2667 static noinline int
2668 rpc_decode_header(struct rpc_task *task, struct xdr_stream *xdr)
2669 {
2670 struct rpc_clnt *clnt = task->tk_client;
2671 int error;
2672 __be32 *p;
2673
2674 /* RFC-1014 says that the representation of XDR data must be a
2675 * multiple of four bytes
2676 * - if it isn't pointer subtraction in the NFS client may give
2677 * undefined results
2678 */
2679 if (task->tk_rqstp->rq_rcv_buf.len & 3)
2680 goto out_unparsable;
2681
2682 p = xdr_inline_decode(xdr, 3 * sizeof(*p));
2683 if (!p)
2684 goto out_unparsable;
2685 p++; /* skip XID */
2686 if (*p++ != rpc_reply)
2687 goto out_unparsable;
2688 if (*p++ != rpc_msg_accepted)
2689 goto out_msg_denied;
2690
2691 error = rpcauth_checkverf(task, xdr);
2692 if (error) {
2693 struct rpc_cred *cred = task->tk_rqstp->rq_cred;
2694
2695 if (!test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
2696 rpcauth_invalcred(task);
2697 if (!task->tk_cred_retry)
2698 goto out_err;
2699 task->tk_cred_retry--;
2700 trace_rpc__stale_creds(task);
2701 return -EKEYREJECTED;
2702 }
2703 goto out_verifier;
2704 }
2705
2706 p = xdr_inline_decode(xdr, sizeof(*p));
2707 if (!p)
2708 goto out_unparsable;
2709 switch (*p) {
2710 case rpc_success:
2711 return 0;
2712 case rpc_prog_unavail:
2713 trace_rpc__prog_unavail(task);
2714 error = -EPFNOSUPPORT;
2715 goto out_err;
2716 case rpc_prog_mismatch:
2717 trace_rpc__prog_mismatch(task);
2718 error = -EPROTONOSUPPORT;
2719 goto out_err;
2720 case rpc_proc_unavail:
2721 trace_rpc__proc_unavail(task);
2722 error = -EOPNOTSUPP;
2723 goto out_err;
2724 case rpc_garbage_args:
2725 case rpc_system_err:
2726 trace_rpc__garbage_args(task);
2727 error = -EIO;
2728 break;
2729 default:
2730 goto out_unparsable;
2731 }
2732
2733 out_garbage:
2734 clnt->cl_stats->rpcgarbage++;
2735 if (task->tk_garb_retry) {
2736 task->tk_garb_retry--;
2737 task->tk_action = call_encode;
2738 return -EAGAIN;
2739 }
2740 out_err:
2741 rpc_call_rpcerror(task, error);
2742 return error;
2743
2744 out_unparsable:
2745 trace_rpc__unparsable(task);
2746 error = -EIO;
2747 goto out_garbage;
2748
2749 out_verifier:
2750 trace_rpc_bad_verifier(task);
2751 switch (error) {
2752 case -EPROTONOSUPPORT:
2753 goto out_err;
2754 case -EACCES:
2755 /* Re-encode with a fresh cred */
2756 fallthrough;
2757 default:
2758 goto out_garbage;
2759 }
2760
2761 out_msg_denied:
2762 error = -EACCES;
2763 p = xdr_inline_decode(xdr, sizeof(*p));
2764 if (!p)
2765 goto out_unparsable;
2766 switch (*p++) {
2767 case rpc_auth_error:
2768 break;
2769 case rpc_mismatch:
2770 trace_rpc__mismatch(task);
2771 error = -EPROTONOSUPPORT;
2772 goto out_err;
2773 default:
2774 goto out_unparsable;
2775 }
2776
2777 p = xdr_inline_decode(xdr, sizeof(*p));
2778 if (!p)
2779 goto out_unparsable;
2780 switch (*p++) {
2781 case rpc_autherr_rejectedcred:
2782 case rpc_autherr_rejectedverf:
2783 case rpcsec_gsserr_credproblem:
2784 case rpcsec_gsserr_ctxproblem:
2785 rpcauth_invalcred(task);
2786 if (!task->tk_cred_retry)
2787 break;
2788 task->tk_cred_retry--;
2789 trace_rpc__stale_creds(task);
2790 return -EKEYREJECTED;
2791 case rpc_autherr_badcred:
2792 case rpc_autherr_badverf:
2793 /* possibly garbled cred/verf? */
2794 if (!task->tk_garb_retry)
2795 break;
2796 task->tk_garb_retry--;
2797 trace_rpc__bad_creds(task);
2798 task->tk_action = call_encode;
2799 return -EAGAIN;
2800 case rpc_autherr_tooweak:
2801 trace_rpc__auth_tooweak(task);
2802 pr_warn("RPC: server %s requires stronger authentication.\n",
2803 task->tk_xprt->servername);
2804 break;
2805 default:
2806 goto out_unparsable;
2807 }
2808 goto out_err;
2809 }
2810
2811 static void rpcproc_encode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2812 const void *obj)
2813 {
2814 }
2815
2816 static int rpcproc_decode_null(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
2817 void *obj)
2818 {
2819 return 0;
2820 }
2821
2822 static const struct rpc_procinfo rpcproc_null = {
2823 .p_encode = rpcproc_encode_null,
2824 .p_decode = rpcproc_decode_null,
2825 };
2826
2827 static const struct rpc_procinfo rpcproc_null_noreply = {
2828 .p_encode = rpcproc_encode_null,
2829 };
2830
2831 static void
2832 rpc_null_call_prepare(struct rpc_task *task, void *data)
2833 {
2834 task->tk_flags &= ~RPC_TASK_NO_RETRANS_TIMEOUT;
2835 rpc_call_start(task);
2836 }
2837
2838 static const struct rpc_call_ops rpc_null_ops = {
2839 .rpc_call_prepare = rpc_null_call_prepare,
2840 .rpc_call_done = rpc_default_callback,
2841 };
2842
2843 static
2844 struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
2845 struct rpc_xprt *xprt, struct rpc_cred *cred, int flags,
2846 const struct rpc_call_ops *ops, void *data)
2847 {
2848 struct rpc_message msg = {
2849 .rpc_proc = &rpcproc_null,
2850 };
2851 struct rpc_task_setup task_setup_data = {
2852 .rpc_client = clnt,
2853 .rpc_xprt = xprt,
2854 .rpc_message = &msg,
2855 .rpc_op_cred = cred,
2856 .callback_ops = ops ?: &rpc_null_ops,
2857 .callback_data = data,
2858 .flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
2859 RPC_TASK_NULLCREDS,
2860 };
2861
2862 return rpc_run_task(&task_setup_data);
2863 }
2864
2865 struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred, int flags)
2866 {
2867 return rpc_call_null_helper(clnt, NULL, cred, flags, NULL, NULL);
2868 }
2869 EXPORT_SYMBOL_GPL(rpc_call_null);
2870
2871 static int rpc_ping(struct rpc_clnt *clnt)
2872 {
2873 struct rpc_task *task;
2874 int status;
2875
2876 if (clnt->cl_auth->au_ops->ping)
2877 return clnt->cl_auth->au_ops->ping(clnt);
2878
2879 task = rpc_call_null_helper(clnt, NULL, NULL, 0, NULL, NULL);
2880 if (IS_ERR(task))
2881 return PTR_ERR(task);
2882 status = task->tk_status;
2883 rpc_put_task(task);
2884 return status;
2885 }
2886
2887 static int rpc_ping_noreply(struct rpc_clnt *clnt)
2888 {
2889 struct rpc_message msg = {
2890 .rpc_proc = &rpcproc_null_noreply,
2891 };
2892 struct rpc_task_setup task_setup_data = {
2893 .rpc_client = clnt,
2894 .rpc_message = &msg,
2895 .callback_ops = &rpc_null_ops,
2896 .flags = RPC_TASK_SOFT | RPC_TASK_SOFTCONN | RPC_TASK_NULLCREDS,
2897 };
2898 struct rpc_task *task;
2899 int status;
2900
2901 task = rpc_run_task(&task_setup_data);
2902 if (IS_ERR(task))
2903 return PTR_ERR(task);
2904 status = task->tk_status;
2905 rpc_put_task(task);
2906 return status;
2907 }
2908
2909 struct rpc_cb_add_xprt_calldata {
2910 struct rpc_xprt_switch *xps;
2911 struct rpc_xprt *xprt;
2912 };
2913
2914 static void rpc_cb_add_xprt_done(struct rpc_task *task, void *calldata)
2915 {
2916 struct rpc_cb_add_xprt_calldata *data = calldata;
2917
2918 if (task->tk_status == 0)
2919 rpc_xprt_switch_add_xprt(data->xps, data->xprt);
2920 }
2921
2922 static void rpc_cb_add_xprt_release(void *calldata)
2923 {
2924 struct rpc_cb_add_xprt_calldata *data = calldata;
2925
2926 xprt_put(data->xprt);
2927 xprt_switch_put(data->xps);
2928 kfree(data);
2929 }
2930
2931 static const struct rpc_call_ops rpc_cb_add_xprt_call_ops = {
2932 .rpc_call_prepare = rpc_null_call_prepare,
2933 .rpc_call_done = rpc_cb_add_xprt_done,
2934 .rpc_release = rpc_cb_add_xprt_release,
2935 };
2936
2937 /**
2938 * rpc_clnt_test_and_add_xprt - Test and add a new transport to a rpc_clnt
2939 * @clnt: pointer to struct rpc_clnt
2940 * @xps: pointer to struct rpc_xprt_switch,
2941 * @xprt: pointer struct rpc_xprt
2942 * @in_max_connect: pointer to the max_connect value for the passed in xprt transport
2943 */
2944 int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
2945 struct rpc_xprt_switch *xps, struct rpc_xprt *xprt,
2946 void *in_max_connect)
2947 {
2948 struct rpc_cb_add_xprt_calldata *data;
2949 struct rpc_task *task;
2950 int max_connect = clnt->cl_max_connect;
2951
2952 if (in_max_connect)
2953 max_connect = *(int *)in_max_connect;
2954 if (xps->xps_nunique_destaddr_xprts + 1 > max_connect) {
2955 rcu_read_lock();
2956 pr_warn("SUNRPC: reached max allowed number (%d) did not add "
2957 "transport to server: %s\n", max_connect,
2958 rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
2959 rcu_read_unlock();
2960 return -EINVAL;
2961 }
2962
2963 data = kmalloc(sizeof(*data), GFP_KERNEL);
2964 if (!data)
2965 return -ENOMEM;
2966 data->xps = xprt_switch_get(xps);
2967 data->xprt = xprt_get(xprt);
2968 if (rpc_xprt_switch_has_addr(data->xps, (struct sockaddr *)&xprt->addr)) {
2969 rpc_cb_add_xprt_release(data);
2970 goto success;
2971 }
2972
2973 task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
2974 &rpc_cb_add_xprt_call_ops, data);
2975 if (IS_ERR(task))
2976 return PTR_ERR(task);
2977
2978 data->xps->xps_nunique_destaddr_xprts++;
2979 rpc_put_task(task);
2980 success:
2981 return 1;
2982 }
2983 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
2984
2985 static int rpc_clnt_add_xprt_helper(struct rpc_clnt *clnt,
2986 struct rpc_xprt *xprt,
2987 struct rpc_add_xprt_test *data)
2988 {
2989 struct rpc_task *task;
2990 int status = -EADDRINUSE;
2991
2992 /* Test the connection */
2993 task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
2994 if (IS_ERR(task))
2995 return PTR_ERR(task);
2996
2997 status = task->tk_status;
2998 rpc_put_task(task);
2999
3000 if (status < 0)
3001 return status;
3002
3003 /* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
3004 data->add_xprt_test(clnt, xprt, data->data);
3005
3006 return 0;
3007 }
3008
3009 /**
3010 * rpc_clnt_setup_test_and_add_xprt()
3011 *
3012 * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
3013 * 1) caller of the test function must dereference the rpc_xprt_switch
3014 * and the rpc_xprt.
3015 * 2) test function must call rpc_xprt_switch_add_xprt, usually in
3016 * the rpc_call_done routine.
3017 *
3018 * Upon success (return of 1), the test function adds the new
3019 * transport to the rpc_clnt xprt switch
3020 *
3021 * @clnt: struct rpc_clnt to get the new transport
3022 * @xps: the rpc_xprt_switch to hold the new transport
3023 * @xprt: the rpc_xprt to test
3024 * @data: a struct rpc_add_xprt_test pointer that holds the test function
3025 * and test function call data
3026 */
3027 int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
3028 struct rpc_xprt_switch *xps,
3029 struct rpc_xprt *xprt,
3030 void *data)
3031 {
3032 int status = -EADDRINUSE;
3033
3034 xprt = xprt_get(xprt);
3035 xprt_switch_get(xps);
3036
3037 if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
3038 goto out_err;
3039
3040 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3041 if (status < 0)
3042 goto out_err;
3043
3044 status = 1;
3045 out_err:
3046 xprt_put(xprt);
3047 xprt_switch_put(xps);
3048 if (status < 0)
3049 pr_info("RPC: rpc_clnt_test_xprt failed: %d addr %s not "
3050 "added\n", status,
3051 xprt->address_strings[RPC_DISPLAY_ADDR]);
3052 /* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
3053 return status;
3054 }
3055 EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
3056
3057 /**
3058 * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
3059 * @clnt: pointer to struct rpc_clnt
3060 * @xprtargs: pointer to struct xprt_create
3061 * @setup: callback to test and/or set up the connection
3062 * @data: pointer to setup function data
3063 *
3064 * Creates a new transport using the parameters set in args and
3065 * adds it to clnt.
3066 * If ping is set, then test that connectivity succeeds before
3067 * adding the new transport.
3068 *
3069 */
3070 int rpc_clnt_add_xprt(struct rpc_clnt *clnt,
3071 struct xprt_create *xprtargs,
3072 int (*setup)(struct rpc_clnt *,
3073 struct rpc_xprt_switch *,
3074 struct rpc_xprt *,
3075 void *),
3076 void *data)
3077 {
3078 struct rpc_xprt_switch *xps;
3079 struct rpc_xprt *xprt;
3080 unsigned long connect_timeout;
3081 unsigned long reconnect_timeout;
3082 unsigned char resvport, reuseport;
3083 int ret = 0, ident;
3084
3085 rcu_read_lock();
3086 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3087 xprt = xprt_iter_xprt(&clnt->cl_xpi);
3088 if (xps == NULL || xprt == NULL) {
3089 rcu_read_unlock();
3090 xprt_switch_put(xps);
3091 return -EAGAIN;
3092 }
3093 resvport = xprt->resvport;
3094 reuseport = xprt->reuseport;
3095 connect_timeout = xprt->connect_timeout;
3096 reconnect_timeout = xprt->max_reconnect_timeout;
3097 ident = xprt->xprt_class->ident;
3098 rcu_read_unlock();
3099
3100 if (!xprtargs->ident)
3101 xprtargs->ident = ident;
3102 xprtargs->xprtsec = clnt->cl_xprtsec;
3103 xprt = xprt_create_transport(xprtargs);
3104 if (IS_ERR(xprt)) {
3105 ret = PTR_ERR(xprt);
3106 goto out_put_switch;
3107 }
3108 xprt->resvport = resvport;
3109 xprt->reuseport = reuseport;
3110
3111 if (xprtargs->connect_timeout)
3112 connect_timeout = xprtargs->connect_timeout;
3113 if (xprtargs->reconnect_timeout)
3114 reconnect_timeout = xprtargs->reconnect_timeout;
3115 if (xprt->ops->set_connect_timeout != NULL)
3116 xprt->ops->set_connect_timeout(xprt,
3117 connect_timeout,
3118 reconnect_timeout);
3119
3120 rpc_xprt_switch_set_roundrobin(xps);
3121 if (setup) {
3122 ret = setup(clnt, xps, xprt, data);
3123 if (ret != 0)
3124 goto out_put_xprt;
3125 }
3126 rpc_xprt_switch_add_xprt(xps, xprt);
3127 out_put_xprt:
3128 xprt_put(xprt);
3129 out_put_switch:
3130 xprt_switch_put(xps);
3131 return ret;
3132 }
3133 EXPORT_SYMBOL_GPL(rpc_clnt_add_xprt);
3134
3135 static int rpc_xprt_probe_trunked(struct rpc_clnt *clnt,
3136 struct rpc_xprt *xprt,
3137 struct rpc_add_xprt_test *data)
3138 {
3139 struct rpc_xprt *main_xprt;
3140 int status = 0;
3141
3142 xprt_get(xprt);
3143
3144 rcu_read_lock();
3145 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3146 status = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3147 (struct sockaddr *)&main_xprt->addr);
3148 rcu_read_unlock();
3149 xprt_put(main_xprt);
3150 if (status || !test_bit(XPRT_OFFLINE, &xprt->state))
3151 goto out;
3152
3153 status = rpc_clnt_add_xprt_helper(clnt, xprt, data);
3154 out:
3155 xprt_put(xprt);
3156 return status;
3157 }
3158
3159 /* rpc_clnt_probe_trunked_xprt -- probe offlined transport for session trunking
3160 * @clnt rpc_clnt structure
3161 *
3162 * For each offlined transport found in the rpc_clnt structure call
3163 * the function rpc_xprt_probe_trunked() which will determine if this
3164 * transport still belongs to the trunking group.
3165 */
3166 void rpc_clnt_probe_trunked_xprts(struct rpc_clnt *clnt,
3167 struct rpc_add_xprt_test *data)
3168 {
3169 struct rpc_xprt_iter xpi;
3170 int ret;
3171
3172 ret = rpc_clnt_xprt_iter_offline_init(clnt, &xpi);
3173 if (ret)
3174 return;
3175 for (;;) {
3176 struct rpc_xprt *xprt = xprt_iter_get_next(&xpi);
3177
3178 if (!xprt)
3179 break;
3180 ret = rpc_xprt_probe_trunked(clnt, xprt, data);
3181 xprt_put(xprt);
3182 if (ret < 0)
3183 break;
3184 xprt_iter_rewind(&xpi);
3185 }
3186 xprt_iter_destroy(&xpi);
3187 }
3188 EXPORT_SYMBOL_GPL(rpc_clnt_probe_trunked_xprts);
3189
3190 static int rpc_xprt_offline(struct rpc_clnt *clnt,
3191 struct rpc_xprt *xprt,
3192 void *data)
3193 {
3194 struct rpc_xprt *main_xprt;
3195 struct rpc_xprt_switch *xps;
3196 int err = 0;
3197
3198 xprt_get(xprt);
3199
3200 rcu_read_lock();
3201 main_xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
3202 xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
3203 err = rpc_cmp_addr_port((struct sockaddr *)&xprt->addr,
3204 (struct sockaddr *)&main_xprt->addr);
3205 rcu_read_unlock();
3206 xprt_put(main_xprt);
3207 if (err)
3208 goto out;
3209
3210 if (wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_KILLABLE)) {
3211 err = -EINTR;
3212 goto out;
3213 }
3214 xprt_set_offline_locked(xprt, xps);
3215
3216 xprt_release_write(xprt, NULL);
3217 out:
3218 xprt_put(xprt);
3219 xprt_switch_put(xps);
3220 return err;
3221 }
3222
3223 /* rpc_clnt_manage_trunked_xprts -- offline trunked transports
3224 * @clnt rpc_clnt structure
3225 *
3226 * For each active transport found in the rpc_clnt structure call
3227 * the function rpc_xprt_offline() which will identify trunked transports
3228 * and will mark them offline.
3229 */
3230 void rpc_clnt_manage_trunked_xprts(struct rpc_clnt *clnt)
3231 {
3232 rpc_clnt_iterate_for_each_xprt(clnt, rpc_xprt_offline, NULL);
3233 }
3234 EXPORT_SYMBOL_GPL(rpc_clnt_manage_trunked_xprts);
3235
3236 struct connect_timeout_data {
3237 unsigned long connect_timeout;
3238 unsigned long reconnect_timeout;
3239 };
3240
3241 static int
3242 rpc_xprt_set_connect_timeout(struct rpc_clnt *clnt,
3243 struct rpc_xprt *xprt,
3244 void *data)
3245 {
3246 struct connect_timeout_data *timeo = data;
3247
3248 if (xprt->ops->set_connect_timeout)
3249 xprt->ops->set_connect_timeout(xprt,
3250 timeo->connect_timeout,
3251 timeo->reconnect_timeout);
3252 return 0;
3253 }
3254
3255 void
3256 rpc_set_connect_timeout(struct rpc_clnt *clnt,
3257 unsigned long connect_timeout,
3258 unsigned long reconnect_timeout)
3259 {
3260 struct connect_timeout_data timeout = {
3261 .connect_timeout = connect_timeout,
3262 .reconnect_timeout = reconnect_timeout,
3263 };
3264 rpc_clnt_iterate_for_each_xprt(clnt,
3265 rpc_xprt_set_connect_timeout,
3266 &timeout);
3267 }
3268 EXPORT_SYMBOL_GPL(rpc_set_connect_timeout);
3269
3270 void rpc_clnt_xprt_set_online(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3271 {
3272 struct rpc_xprt_switch *xps;
3273
3274 xps = rpc_clnt_xprt_switch_get(clnt);
3275 xprt_set_online_locked(xprt, xps);
3276 xprt_switch_put(xps);
3277 }
3278
3279 void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3280 {
3281 struct rpc_xprt_switch *xps;
3282
3283 if (rpc_clnt_xprt_switch_has_addr(clnt,
3284 (const struct sockaddr *)&xprt->addr)) {
3285 return rpc_clnt_xprt_set_online(clnt, xprt);
3286 }
3287
3288 xps = rpc_clnt_xprt_switch_get(clnt);
3289 rpc_xprt_switch_add_xprt(xps, xprt);
3290 xprt_switch_put(xps);
3291 }
3292 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
3293
3294 void rpc_clnt_xprt_switch_remove_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
3295 {
3296 struct rpc_xprt_switch *xps;
3297
3298 rcu_read_lock();
3299 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3300 rpc_xprt_switch_remove_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
3301 xprt, 0);
3302 xps->xps_nunique_destaddr_xprts--;
3303 rcu_read_unlock();
3304 }
3305 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_remove_xprt);
3306
3307 bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
3308 const struct sockaddr *sap)
3309 {
3310 struct rpc_xprt_switch *xps;
3311 bool ret;
3312
3313 rcu_read_lock();
3314 xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
3315 ret = rpc_xprt_switch_has_addr(xps, sap);
3316 rcu_read_unlock();
3317 return ret;
3318 }
3319 EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
3320
3321 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
3322 static void rpc_show_header(void)
3323 {
3324 printk(KERN_INFO "-pid- flgs status -client- --rqstp- "
3325 "-timeout ---ops--\n");
3326 }
3327
3328 static void rpc_show_task(const struct rpc_clnt *clnt,
3329 const struct rpc_task *task)
3330 {
3331 const char *rpc_waitq = "none";
3332
3333 if (RPC_IS_QUEUED(task))
3334 rpc_waitq = rpc_qname(task->tk_waitqueue);
3335
3336 printk(KERN_INFO "%5u %04x %6d %8p %8p %8ld %8p %sv%u %s a:%ps q:%s\n",
3337 task->tk_pid, task->tk_flags, task->tk_status,
3338 clnt, task->tk_rqstp, rpc_task_timeout(task), task->tk_ops,
3339 clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
3340 task->tk_action, rpc_waitq);
3341 }
3342
3343 void rpc_show_tasks(struct net *net)
3344 {
3345 struct rpc_clnt *clnt;
3346 struct rpc_task *task;
3347 int header = 0;
3348 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
3349
3350 spin_lock(&sn->rpc_client_lock);
3351 list_for_each_entry(clnt, &sn->all_clients, cl_clients) {
3352 spin_lock(&clnt->cl_lock);
3353 list_for_each_entry(task, &clnt->cl_tasks, tk_task) {
3354 if (!header) {
3355 rpc_show_header();
3356 header++;
3357 }
3358 rpc_show_task(clnt, task);
3359 }
3360 spin_unlock(&clnt->cl_lock);
3361 }
3362 spin_unlock(&sn->rpc_client_lock);
3363 }
3364 #endif
3365
3366 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
3367 static int
3368 rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
3369 struct rpc_xprt *xprt,
3370 void *dummy)
3371 {
3372 return xprt_enable_swap(xprt);
3373 }
3374
3375 int
3376 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
3377 {
3378 while (clnt != clnt->cl_parent)
3379 clnt = clnt->cl_parent;
3380 if (atomic_inc_return(&clnt->cl_swapper) == 1)
3381 return rpc_clnt_iterate_for_each_xprt(clnt,
3382 rpc_clnt_swap_activate_callback, NULL);
3383 return 0;
3384 }
3385 EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);
3386
3387 static int
3388 rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
3389 struct rpc_xprt *xprt,
3390 void *dummy)
3391 {
3392 xprt_disable_swap(xprt);
3393 return 0;
3394 }
3395
3396 void
3397 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
3398 {
3399 while (clnt != clnt->cl_parent)
3400 clnt = clnt->cl_parent;
3401 if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
3402 rpc_clnt_iterate_for_each_xprt(clnt,
3403 rpc_clnt_swap_deactivate_callback, NULL);
3404 }
3405 EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
3406 #endif /* CONFIG_SUNRPC_SWAP */
Kernel DRM miscellaneous fixes and cross-tree changes