-
Notifications
You must be signed in to change notification settings - Fork 152
/
Copy pathclnt.c
1867 lines (1674 loc) · 44.2 KB
/
clnt.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* linux/net/sunrpc/clnt.c
*
* This file contains the high-level RPC interface.
* It is modeled as a finite state machine to support both synchronous
* and asynchronous requests.
*
* - RPC header generation and argument serialization.
* - Credential refresh.
* - TCP connect handling.
* - Retry of operation when it is suspected the operation failed because
* of uid squashing on the server, or when the credentials were stale
* and need to be refreshed, or when a packet was damaged in transit.
* This may be have to be moved to the VFS layer.
*
* NB: BSD uses a more intelligent approach to guessing when a request
* or reply has been lost by keeping the RTO estimate for each procedure.
* We currently make do with a constant timeout value.
*
* Copyright (C) 1992,1993 Rick Sladkey <jrs@world.std.com>
* Copyright (C) 1995,1996 Olaf Kirch <okir@monad.swb.de>
*/
#include <asm/system.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kallsyms.h>
#include <linux/mm.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/workqueue.h>
#include <linux/in6.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/sunrpc/metrics.h>
#include <linux/sunrpc/bc_xprt.h>
#include "sunrpc.h"
#ifdef RPC_DEBUG
# define RPCDBG_FACILITY RPCDBG_CALL
#endif
#define dprint_status(t) \
dprintk("RPC: %5u %s (status %d)\n", t->tk_pid, \
__func__, t->tk_status)
/*
* All RPC clients are linked into this list
*/
static LIST_HEAD(all_clients);
static DEFINE_SPINLOCK(rpc_client_lock);
static DECLARE_WAIT_QUEUE_HEAD(destroy_wait);
static void call_start(struct rpc_task *task);
static void call_reserve(struct rpc_task *task);
static void call_reserveresult(struct rpc_task *task);
static void call_allocate(struct rpc_task *task);
static void call_decode(struct rpc_task *task);
static void call_bind(struct rpc_task *task);
static void call_bind_status(struct rpc_task *task);
static void call_transmit(struct rpc_task *task);
#if defined(CONFIG_NFS_V4_1)
static void call_bc_transmit(struct rpc_task *task);
#endif /* CONFIG_NFS_V4_1 */
static void call_status(struct rpc_task *task);
static void call_transmit_status(struct rpc_task *task);
static void call_refresh(struct rpc_task *task);
static void call_refreshresult(struct rpc_task *task);
static void call_timeout(struct rpc_task *task);
static void call_connect(struct rpc_task *task);
static void call_connect_status(struct rpc_task *task);
static __be32 *rpc_encode_header(struct rpc_task *task);
static __be32 *rpc_verify_header(struct rpc_task *task);
static int rpc_ping(struct rpc_clnt *clnt);
static void rpc_register_client(struct rpc_clnt *clnt)
{
spin_lock(&rpc_client_lock);
list_add(&clnt->cl_clients, &all_clients);
spin_unlock(&rpc_client_lock);
}
static void rpc_unregister_client(struct rpc_clnt *clnt)
{
spin_lock(&rpc_client_lock);
list_del(&clnt->cl_clients);
spin_unlock(&rpc_client_lock);
}
static int
rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
{
static uint32_t clntid;
struct nameidata nd;
struct path path;
char name[15];
struct qstr q = {
.name = name,
};
int error;
clnt->cl_path.mnt = ERR_PTR(-ENOENT);
clnt->cl_path.dentry = ERR_PTR(-ENOENT);
if (dir_name == NULL)
return 0;
path.mnt = rpc_get_mount();
if (IS_ERR(path.mnt))
return PTR_ERR(path.mnt);
error = vfs_path_lookup(path.mnt->mnt_root, path.mnt, dir_name, 0, &nd);
if (error)
goto err;
for (;;) {
q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
name[sizeof(name) - 1] = '\0';
q.hash = full_name_hash(q.name, q.len);
path.dentry = rpc_create_client_dir(nd.path.dentry, &q, clnt);
if (!IS_ERR(path.dentry))
break;
error = PTR_ERR(path.dentry);
if (error != -EEXIST) {
printk(KERN_INFO "RPC: Couldn't create pipefs entry"
" %s/%s, error %d\n",
dir_name, name, error);
goto err_path_put;
}
}
path_put(&nd.path);
clnt->cl_path = path;
return 0;
err_path_put:
path_put(&nd.path);
err:
rpc_put_mount();
return error;
}
static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, struct rpc_xprt *xprt)
{
struct rpc_program *program = args->program;
struct rpc_version *version;
struct rpc_clnt *clnt = NULL;
struct rpc_auth *auth;
int err;
size_t len;
/* sanity check the name before trying to print it */
err = -EINVAL;
len = strlen(args->servername);
if (len > RPC_MAXNETNAMELEN)
goto out_no_rpciod;
len++;
dprintk("RPC: creating %s client for %s (xprt %p)\n",
program->name, args->servername, xprt);
err = rpciod_up();
if (err)
goto out_no_rpciod;
err = -EINVAL;
if (!xprt)
goto out_no_xprt;
if (args->version >= program->nrvers)
goto out_err;
version = program->version[args->version];
if (version == NULL)
goto out_err;
err = -ENOMEM;
clnt = kzalloc(sizeof(*clnt), GFP_KERNEL);
if (!clnt)
goto out_err;
clnt->cl_parent = clnt;
clnt->cl_server = clnt->cl_inline_name;
if (len > sizeof(clnt->cl_inline_name)) {
char *buf = kmalloc(len, GFP_KERNEL);
if (buf != NULL)
clnt->cl_server = buf;
else
len = sizeof(clnt->cl_inline_name);
}
strlcpy(clnt->cl_server, args->servername, len);
clnt->cl_xprt = xprt;
clnt->cl_procinfo = version->procs;
clnt->cl_maxproc = version->nrprocs;
clnt->cl_protname = program->name;
clnt->cl_prog = args->prognumber ? : program->number;
clnt->cl_vers = version->number;
clnt->cl_stats = program->stats;
clnt->cl_metrics = rpc_alloc_iostats(clnt);
err = -ENOMEM;
if (clnt->cl_metrics == NULL)
goto out_no_stats;
clnt->cl_program = program;
INIT_LIST_HEAD(&clnt->cl_tasks);
spin_lock_init(&clnt->cl_lock);
if (!xprt_bound(clnt->cl_xprt))
clnt->cl_autobind = 1;
clnt->cl_timeout = xprt->timeout;
if (args->timeout != NULL) {
memcpy(&clnt->cl_timeout_default, args->timeout,
sizeof(clnt->cl_timeout_default));
clnt->cl_timeout = &clnt->cl_timeout_default;
}
clnt->cl_rtt = &clnt->cl_rtt_default;
rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
clnt->cl_principal = NULL;
if (args->client_name) {
clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
if (!clnt->cl_principal)
goto out_no_principal;
}
kref_init(&clnt->cl_kref);
err = rpc_setup_pipedir(clnt, program->pipe_dir_name);
if (err < 0)
goto out_no_path;
auth = rpcauth_create(args->authflavor, clnt);
if (IS_ERR(auth)) {
printk(KERN_INFO "RPC: Couldn't create auth handle (flavor %u)\n",
args->authflavor);
err = PTR_ERR(auth);
goto out_no_auth;
}
/* save the nodename */
clnt->cl_nodelen = strlen(init_utsname()->nodename);
if (clnt->cl_nodelen > UNX_MAXNODENAME)
clnt->cl_nodelen = UNX_MAXNODENAME;
memcpy(clnt->cl_nodename, init_utsname()->nodename, clnt->cl_nodelen);
rpc_register_client(clnt);
return clnt;
out_no_auth:
if (!IS_ERR(clnt->cl_path.dentry)) {
rpc_remove_client_dir(clnt->cl_path.dentry);
rpc_put_mount();
}
out_no_path:
kfree(clnt->cl_principal);
out_no_principal:
rpc_free_iostats(clnt->cl_metrics);
out_no_stats:
if (clnt->cl_server != clnt->cl_inline_name)
kfree(clnt->cl_server);
kfree(clnt);
out_err:
xprt_put(xprt);
out_no_xprt:
rpciod_down();
out_no_rpciod:
return ERR_PTR(err);
}
/*
* rpc_create - create an RPC client and transport with one call
* @args: rpc_clnt create argument structure
*
* Creates and initializes an RPC transport and an RPC client.
*
* It can ping the server in order to determine if it is up, and to see if
* it supports this program and version. RPC_CLNT_CREATE_NOPING disables
* this behavior so asynchronous tasks can also use rpc_create.
*/
struct rpc_clnt *rpc_create(struct rpc_create_args *args)
{
struct rpc_xprt *xprt;
struct rpc_clnt *clnt;
struct xprt_create xprtargs = {
.ident = args->protocol,
.srcaddr = args->saddress,
.dstaddr = args->address,
.addrlen = args->addrsize,
.bc_xprt = args->bc_xprt,
};
char servername[48];
/*
* If the caller chooses not to specify a hostname, whip
* up a string representation of the passed-in address.
*/
if (args->servername == NULL) {
servername[0] = '\0';
switch (args->address->sa_family) {
case AF_INET: {
struct sockaddr_in *sin =
(struct sockaddr_in *)args->address;
snprintf(servername, sizeof(servername), "%pI4",
&sin->sin_addr.s_addr);
break;
}
case AF_INET6: {
struct sockaddr_in6 *sin =
(struct sockaddr_in6 *)args->address;
snprintf(servername, sizeof(servername), "%pI6",
&sin->sin6_addr);
break;
}
default:
/* caller wants default server name, but
* address family isn't recognized. */
return ERR_PTR(-EINVAL);
}
args->servername = servername;
}
xprt = xprt_create_transport(&xprtargs);
if (IS_ERR(xprt))
return (struct rpc_clnt *)xprt;
/*
* By default, kernel RPC client connects from a reserved port.
* CAP_NET_BIND_SERVICE will not be set for unprivileged requesters,
* but it is always enabled for rpciod, which handles the connect
* operation.
*/
xprt->resvport = 1;
if (args->flags & RPC_CLNT_CREATE_NONPRIVPORT)
xprt->resvport = 0;
clnt = rpc_new_client(args, xprt);
if (IS_ERR(clnt))
return clnt;
if (!(args->flags & RPC_CLNT_CREATE_NOPING)) {
int err = rpc_ping(clnt);
if (err != 0) {
rpc_shutdown_client(clnt);
return ERR_PTR(err);
}
}
clnt->cl_softrtry = 1;
if (args->flags & RPC_CLNT_CREATE_HARDRTRY)
clnt->cl_softrtry = 0;
if (args->flags & RPC_CLNT_CREATE_AUTOBIND)
clnt->cl_autobind = 1;
if (args->flags & RPC_CLNT_CREATE_DISCRTRY)
clnt->cl_discrtry = 1;
if (!(args->flags & RPC_CLNT_CREATE_QUIET))
clnt->cl_chatty = 1;
return clnt;
}
EXPORT_SYMBOL_GPL(rpc_create);
/*
* This function clones the RPC client structure. It allows us to share the
* same transport while varying parameters such as the authentication
* flavour.
*/
struct rpc_clnt *
rpc_clone_client(struct rpc_clnt *clnt)
{
struct rpc_clnt *new;
int err = -ENOMEM;
new = kmemdup(clnt, sizeof(*new), GFP_KERNEL);
if (!new)
goto out_no_clnt;
new->cl_parent = clnt;
/* Turn off autobind on clones */
new->cl_autobind = 0;
INIT_LIST_HEAD(&new->cl_tasks);
spin_lock_init(&new->cl_lock);
rpc_init_rtt(&new->cl_rtt_default, clnt->cl_timeout->to_initval);
new->cl_metrics = rpc_alloc_iostats(clnt);
if (new->cl_metrics == NULL)
goto out_no_stats;
if (clnt->cl_principal) {
new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
if (new->cl_principal == NULL)
goto out_no_principal;
}
kref_init(&new->cl_kref);
err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
if (err != 0)
goto out_no_path;
if (new->cl_auth)
atomic_inc(&new->cl_auth->au_count);
xprt_get(clnt->cl_xprt);
kref_get(&clnt->cl_kref);
rpc_register_client(new);
rpciod_up();
return new;
out_no_path:
kfree(new->cl_principal);
out_no_principal:
rpc_free_iostats(new->cl_metrics);
out_no_stats:
kfree(new);
out_no_clnt:
dprintk("RPC: %s: returned error %d\n", __func__, err);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(rpc_clone_client);
/*
* Kill all tasks for the given client.
* XXX: kill their descendants as well?
*/
void rpc_killall_tasks(struct rpc_clnt *clnt)
{
struct rpc_task *rovr;
if (list_empty(&clnt->cl_tasks))
return;
dprintk("RPC: killing all tasks for client %p\n", clnt);
/*
* Spin lock all_tasks to prevent changes...
*/
spin_lock(&clnt->cl_lock);
list_for_each_entry(rovr, &clnt->cl_tasks, tk_task) {
if (!RPC_IS_ACTIVATED(rovr))
continue;
if (!(rovr->tk_flags & RPC_TASK_KILLED)) {
rovr->tk_flags |= RPC_TASK_KILLED;
rpc_exit(rovr, -EIO);
rpc_wake_up_queued_task(rovr->tk_waitqueue, rovr);
}
}
spin_unlock(&clnt->cl_lock);
}
EXPORT_SYMBOL_GPL(rpc_killall_tasks);
/*
* Properly shut down an RPC client, terminating all outstanding
* requests.
*/
void rpc_shutdown_client(struct rpc_clnt *clnt)
{
dprintk("RPC: shutting down %s client for %s\n",
clnt->cl_protname, clnt->cl_server);
while (!list_empty(&clnt->cl_tasks)) {
rpc_killall_tasks(clnt);
wait_event_timeout(destroy_wait,
list_empty(&clnt->cl_tasks), 1*HZ);
}
rpc_release_client(clnt);
}
EXPORT_SYMBOL_GPL(rpc_shutdown_client);
/*
* Free an RPC client
*/
static void
rpc_free_client(struct kref *kref)
{
struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
dprintk("RPC: destroying %s client for %s\n",
clnt->cl_protname, clnt->cl_server);
if (!IS_ERR(clnt->cl_path.dentry)) {
rpc_remove_client_dir(clnt->cl_path.dentry);
rpc_put_mount();
}
if (clnt->cl_parent != clnt) {
rpc_release_client(clnt->cl_parent);
goto out_free;
}
if (clnt->cl_server != clnt->cl_inline_name)
kfree(clnt->cl_server);
out_free:
rpc_unregister_client(clnt);
rpc_free_iostats(clnt->cl_metrics);
kfree(clnt->cl_principal);
clnt->cl_metrics = NULL;
xprt_put(clnt->cl_xprt);
rpciod_down();
kfree(clnt);
}
/*
* Free an RPC client
*/
static void
rpc_free_auth(struct kref *kref)
{
struct rpc_clnt *clnt = container_of(kref, struct rpc_clnt, cl_kref);
if (clnt->cl_auth == NULL) {
rpc_free_client(kref);
return;
}
/*
* Note: RPCSEC_GSS may need to send NULL RPC calls in order to
* release remaining GSS contexts. This mechanism ensures
* that it can do so safely.
*/
kref_init(kref);
rpcauth_release(clnt->cl_auth);
clnt->cl_auth = NULL;
kref_put(kref, rpc_free_client);
}
/*
* Release reference to the RPC client
*/
void
rpc_release_client(struct rpc_clnt *clnt)
{
dprintk("RPC: rpc_release_client(%p)\n", clnt);
if (list_empty(&clnt->cl_tasks))
wake_up(&destroy_wait);
kref_put(&clnt->cl_kref, rpc_free_auth);
}
/**
* rpc_bind_new_program - bind a new RPC program to an existing client
* @old: old rpc_client
* @program: rpc program to set
* @vers: rpc program version
*
* Clones the rpc client and sets up a new RPC program. This is mainly
* of use for enabling different RPC programs to share the same transport.
* The Sun NFSv2/v3 ACL protocol can do this.
*/
struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old,
struct rpc_program *program,
u32 vers)
{
struct rpc_clnt *clnt;
struct rpc_version *version;
int err;
BUG_ON(vers >= program->nrvers || !program->version[vers]);
version = program->version[vers];
clnt = rpc_clone_client(old);
if (IS_ERR(clnt))
goto out;
clnt->cl_procinfo = version->procs;
clnt->cl_maxproc = version->nrprocs;
clnt->cl_protname = program->name;
clnt->cl_prog = program->number;
clnt->cl_vers = version->number;
clnt->cl_stats = program->stats;
err = rpc_ping(clnt);
if (err != 0) {
rpc_shutdown_client(clnt);
clnt = ERR_PTR(err);
}
out:
return clnt;
}
EXPORT_SYMBOL_GPL(rpc_bind_new_program);
void rpc_task_release_client(struct rpc_task *task)
{
struct rpc_clnt *clnt = task->tk_client;
if (clnt != NULL) {
/* Remove from client task list */
spin_lock(&clnt->cl_lock);
list_del(&task->tk_task);
spin_unlock(&clnt->cl_lock);
task->tk_client = NULL;
rpc_release_client(clnt);
}
}
static
void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
{
if (clnt != NULL) {
rpc_task_release_client(task);
task->tk_client = clnt;
kref_get(&clnt->cl_kref);
if (clnt->cl_softrtry)
task->tk_flags |= RPC_TASK_SOFT;
/* Add to the client's list of all tasks */
spin_lock(&clnt->cl_lock);
list_add_tail(&task->tk_task, &clnt->cl_tasks);
spin_unlock(&clnt->cl_lock);
}
}
static void
rpc_task_set_rpc_message(struct rpc_task *task, const struct rpc_message *msg)
{
if (msg != NULL) {
task->tk_msg.rpc_proc = msg->rpc_proc;
task->tk_msg.rpc_argp = msg->rpc_argp;
task->tk_msg.rpc_resp = msg->rpc_resp;
if (msg->rpc_cred != NULL)
task->tk_msg.rpc_cred = get_rpccred(msg->rpc_cred);
}
}
/*
* Default callback for async RPC calls
*/
static void
rpc_default_callback(struct rpc_task *task, void *data)
{
}
static const struct rpc_call_ops rpc_default_ops = {
.rpc_call_done = rpc_default_callback,
};
/**
* rpc_run_task - Allocate a new RPC task, then run rpc_execute against it
* @task_setup_data: pointer to task initialisation data
*/
struct rpc_task *rpc_run_task(const struct rpc_task_setup *task_setup_data)
{
struct rpc_task *task;
task = rpc_new_task(task_setup_data);
if (IS_ERR(task))
goto out;
rpc_task_set_client(task, task_setup_data->rpc_client);
rpc_task_set_rpc_message(task, task_setup_data->rpc_message);
if (task->tk_status != 0) {
int ret = task->tk_status;
rpc_put_task(task);
return ERR_PTR(ret);
}
if (task->tk_action == NULL)
rpc_call_start(task);
atomic_inc(&task->tk_count);
rpc_execute(task);
out:
return task;
}
EXPORT_SYMBOL_GPL(rpc_run_task);
/**
* rpc_call_sync - Perform a synchronous RPC call
* @clnt: pointer to RPC client
* @msg: RPC call parameters
* @flags: RPC call flags
*/
int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
{
struct rpc_task *task;
struct rpc_task_setup task_setup_data = {
.rpc_client = clnt,
.rpc_message = msg,
.callback_ops = &rpc_default_ops,
.flags = flags,
};
int status;
BUG_ON(flags & RPC_TASK_ASYNC);
task = rpc_run_task(&task_setup_data);
if (IS_ERR(task))
return PTR_ERR(task);
status = task->tk_status;
rpc_put_task(task);
return status;
}
EXPORT_SYMBOL_GPL(rpc_call_sync);
/**
* rpc_call_async - Perform an asynchronous RPC call
* @clnt: pointer to RPC client
* @msg: RPC call parameters
* @flags: RPC call flags
* @tk_ops: RPC call ops
* @data: user call data
*/
int
rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
const struct rpc_call_ops *tk_ops, void *data)
{
struct rpc_task *task;
struct rpc_task_setup task_setup_data = {
.rpc_client = clnt,
.rpc_message = msg,
.callback_ops = tk_ops,
.callback_data = data,
.flags = flags|RPC_TASK_ASYNC,
};
task = rpc_run_task(&task_setup_data);
if (IS_ERR(task))
return PTR_ERR(task);
rpc_put_task(task);
return 0;
}
EXPORT_SYMBOL_GPL(rpc_call_async);
#if defined(CONFIG_NFS_V4_1)
/**
* rpc_run_bc_task - Allocate a new RPC task for backchannel use, then run
* rpc_execute against it
* @req: RPC request
* @tk_ops: RPC call ops
*/
struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
const struct rpc_call_ops *tk_ops)
{
struct rpc_task *task;
struct xdr_buf *xbufp = &req->rq_snd_buf;
struct rpc_task_setup task_setup_data = {
.callback_ops = tk_ops,
};
dprintk("RPC: rpc_run_bc_task req= %p\n", req);
/*
* Create an rpc_task to send the data
*/
task = rpc_new_task(&task_setup_data);
if (IS_ERR(task)) {
xprt_free_bc_request(req);
goto out;
}
task->tk_rqstp = req;
/*
* Set up the xdr_buf length.
* This also indicates that the buffer is XDR encoded already.
*/
xbufp->len = xbufp->head[0].iov_len + xbufp->page_len +
xbufp->tail[0].iov_len;
task->tk_action = call_bc_transmit;
atomic_inc(&task->tk_count);
BUG_ON(atomic_read(&task->tk_count) != 2);
rpc_execute(task);
out:
dprintk("RPC: rpc_run_bc_task: task= %p\n", task);
return task;
}
#endif /* CONFIG_NFS_V4_1 */
void
rpc_call_start(struct rpc_task *task)
{
task->tk_action = call_start;
}
EXPORT_SYMBOL_GPL(rpc_call_start);
/**
* rpc_peeraddr - extract remote peer address from clnt's xprt
* @clnt: RPC client structure
* @buf: target buffer
* @bufsize: length of target buffer
*
* Returns the number of bytes that are actually in the stored address.
*/
size_t rpc_peeraddr(struct rpc_clnt *clnt, struct sockaddr *buf, size_t bufsize)
{
size_t bytes;
struct rpc_xprt *xprt = clnt->cl_xprt;
bytes = sizeof(xprt->addr);
if (bytes > bufsize)
bytes = bufsize;
memcpy(buf, &clnt->cl_xprt->addr, bytes);
return xprt->addrlen;
}
EXPORT_SYMBOL_GPL(rpc_peeraddr);
/**
* rpc_peeraddr2str - return remote peer address in printable format
* @clnt: RPC client structure
* @format: address format
*
*/
const char *rpc_peeraddr2str(struct rpc_clnt *clnt,
enum rpc_display_format_t format)
{
struct rpc_xprt *xprt = clnt->cl_xprt;
if (xprt->address_strings[format] != NULL)
return xprt->address_strings[format];
else
return "unprintable";
}
EXPORT_SYMBOL_GPL(rpc_peeraddr2str);
void
rpc_setbufsize(struct rpc_clnt *clnt, unsigned int sndsize, unsigned int rcvsize)
{
struct rpc_xprt *xprt = clnt->cl_xprt;
if (xprt->ops->set_buffer_size)
xprt->ops->set_buffer_size(xprt, sndsize, rcvsize);
}
EXPORT_SYMBOL_GPL(rpc_setbufsize);
/*
* Return size of largest payload RPC client can support, in bytes
*
* For stream transports, this is one RPC record fragment (see RFC
* 1831), as we don't support multi-record requests yet. For datagram
* transports, this is the size of an IP packet minus the IP, UDP, and
* RPC header sizes.
*/
size_t rpc_max_payload(struct rpc_clnt *clnt)
{
return clnt->cl_xprt->max_payload;
}
EXPORT_SYMBOL_GPL(rpc_max_payload);
/**
* rpc_force_rebind - force transport to check that remote port is unchanged
* @clnt: client to rebind
*
*/
void rpc_force_rebind(struct rpc_clnt *clnt)
{
if (clnt->cl_autobind)
xprt_clear_bound(clnt->cl_xprt);
}
EXPORT_SYMBOL_GPL(rpc_force_rebind);
/*
* Restart an (async) RPC call from the call_prepare state.
* Usually called from within the exit handler.
*/
int
rpc_restart_call_prepare(struct rpc_task *task)
{
if (RPC_ASSASSINATED(task))
return 0;
task->tk_action = rpc_prepare_task;
return 1;
}
EXPORT_SYMBOL_GPL(rpc_restart_call_prepare);
/*
* Restart an (async) RPC call. Usually called from within the
* exit handler.
*/
int
rpc_restart_call(struct rpc_task *task)
{
if (RPC_ASSASSINATED(task))
return 0;
task->tk_action = call_start;
return 1;
}
EXPORT_SYMBOL_GPL(rpc_restart_call);
#ifdef RPC_DEBUG
static const char *rpc_proc_name(const struct rpc_task *task)
{
const struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
if (proc) {
if (proc->p_name)
return proc->p_name;
else
return "NULL";
} else
return "no proc";
}
#endif
/*
* 0. Initial state
*
* Other FSM states can be visited zero or more times, but
* this state is visited exactly once for each RPC.
*/
static void
call_start(struct rpc_task *task)
{
struct rpc_clnt *clnt = task->tk_client;
dprintk("RPC: %5u call_start %s%d proc %s (%s)\n", task->tk_pid,
clnt->cl_protname, clnt->cl_vers,
rpc_proc_name(task),
(RPC_IS_ASYNC(task) ? "async" : "sync"));
/* Increment call count */
task->tk_msg.rpc_proc->p_count++;
clnt->cl_stats->rpccnt++;
task->tk_action = call_reserve;
}
/*
* 1. Reserve an RPC call slot
*/
static void
call_reserve(struct rpc_task *task)
{
dprint_status(task);
task->tk_status = 0;
task->tk_action = call_reserveresult;
xprt_reserve(task);
}
/*
* 1b. Grok the result of xprt_reserve()
*/
static void
call_reserveresult(struct rpc_task *task)
{
int status = task->tk_status;
dprint_status(task);
/*
* After a call to xprt_reserve(), we must have either
* a request slot or else an error status.
*/
task->tk_status = 0;
if (status >= 0) {
if (task->tk_rqstp) {
task->tk_action = call_allocate;
return;
}
printk(KERN_ERR "%s: status=%d, but no request slot, exiting\n",
__func__, status);
rpc_exit(task, -EIO);
return;
}
/*
* Even though there was an error, we may have acquired
* a request slot somehow. Make sure not to leak it.
*/
if (task->tk_rqstp) {
printk(KERN_ERR "%s: status=%d, request allocated anyway\n",
__func__, status);
xprt_release(task);
}
switch (status) {
case -EAGAIN: /* woken up; retry */
task->tk_action = call_reserve;
return;
case -EIO: /* probably a shutdown */
break;
default:
printk(KERN_ERR "%s: unrecognized error %d, exiting\n",
__func__, status);
break;
}
rpc_exit(task, status);
}
/*
* 2. Allocate the buffer. For details, see sched.c:rpc_malloc.
* (Note: buffer memory is freed in xprt_release).
*/
static void
call_allocate(struct rpc_task *task)
{
unsigned int slack = task->tk_client->cl_auth->au_cslack;
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_xprt *xprt = task->tk_xprt;
struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
dprint_status(task);
task->tk_status = 0;
task->tk_action = call_refresh;
if (req->rq_buffer)
return;
if (proc->p_proc != 0) {
BUG_ON(proc->p_arglen == 0);
if (proc->p_decode != NULL)
BUG_ON(proc->p_replen == 0);
}
/*
* Calculate the size (in quads) of the RPC call
* and reply headers, and convert both values
* to byte sizes.
*/
req->rq_callsize = RPC_CALLHDRSIZE + (slack << 1) + proc->p_arglen;
req->rq_callsize <<= 2;