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