forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathbcm.c
1622 lines (1317 loc) · 39 KB
/
bcm.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
/*
* bcm.c - Broadcast Manager to filter/send (cyclic) CAN content
*
* Copyright (c) 2002-2007 Volkswagen Group Electronic Research
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Volkswagen nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* Alternatively, provided that this notice is retained in full, this
* software may be distributed under the terms of the GNU General
* Public License ("GPL") version 2, in which case the provisions of the
* GPL apply INSTEAD OF those given above.
*
* The provided data structures and external interfaces from this code
* are not restricted to be used by modules with a GPL compatible license.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* Send feedback to <socketcan-users@lists.berlios.de>
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/hrtimer.h>
#include <linux/list.h>
#include <linux/proc_fs.h>
#include <linux/uio.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/socket.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
#include <linux/can/bcm.h>
#include <net/sock.h>
#include <net/net_namespace.h>
/* use of last_frames[index].can_dlc */
#define RX_RECV 0x40 /* received data for this element */
#define RX_THR 0x80 /* element not been sent due to throttle feature */
#define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
/* get best masking value for can_rx_register() for a given single can_id */
#define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
(CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
(CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
#define CAN_BCM_VERSION CAN_VERSION
static __initdata const char banner[] = KERN_INFO
"can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
/* easy access to can_frame payload */
static inline u64 GET_U64(const struct can_frame *cp)
{
return *(u64 *)cp->data;
}
struct bcm_op {
struct list_head list;
int ifindex;
canid_t can_id;
int flags;
unsigned long frames_abs, frames_filtered;
struct timeval ival1, ival2;
struct hrtimer timer, thrtimer;
struct tasklet_struct tsklet, thrtsklet;
ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
int rx_ifindex;
int count;
int nframes;
int currframe;
struct can_frame *frames;
struct can_frame *last_frames;
struct can_frame sframe;
struct can_frame last_sframe;
struct sock *sk;
struct net_device *rx_reg_dev;
};
static struct proc_dir_entry *proc_dir;
struct bcm_sock {
struct sock sk;
int bound;
int ifindex;
struct notifier_block notifier;
struct list_head rx_ops;
struct list_head tx_ops;
unsigned long dropped_usr_msgs;
struct proc_dir_entry *bcm_proc_read;
char procname [9]; /* pointer printed in ASCII with \0 */
};
static inline struct bcm_sock *bcm_sk(const struct sock *sk)
{
return (struct bcm_sock *)sk;
}
#define CFSIZ sizeof(struct can_frame)
#define OPSIZ sizeof(struct bcm_op)
#define MHSIZ sizeof(struct bcm_msg_head)
/*
* procfs functions
*/
static char *bcm_proc_getifname(int ifindex)
{
struct net_device *dev;
if (!ifindex)
return "any";
/* no usage counting */
dev = __dev_get_by_index(&init_net, ifindex);
if (dev)
return dev->name;
return "???";
}
static int bcm_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
int len = 0;
struct sock *sk = (struct sock *)data;
struct bcm_sock *bo = bcm_sk(sk);
struct bcm_op *op;
len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
sk->sk_socket);
len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
bo->dropped_usr_msgs);
len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
bcm_proc_getifname(bo->ifindex));
len += snprintf(page + len, PAGE_SIZE - len, " <<<\n");
list_for_each_entry(op, &bo->rx_ops, list) {
unsigned long reduction;
/* print only active entries & prevent division by zero */
if (!op->frames_abs)
continue;
len += snprintf(page + len, PAGE_SIZE - len,
"rx_op: %03X %-5s ",
op->can_id, bcm_proc_getifname(op->ifindex));
len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
op->nframes,
(op->flags & RX_CHECK_DLC)?'d':' ');
if (op->kt_ival1.tv64)
len += snprintf(page + len, PAGE_SIZE - len,
"timeo=%lld ",
(long long)
ktime_to_us(op->kt_ival1));
if (op->kt_ival2.tv64)
len += snprintf(page + len, PAGE_SIZE - len,
"thr=%lld ",
(long long)
ktime_to_us(op->kt_ival2));
len += snprintf(page + len, PAGE_SIZE - len,
"# recv %ld (%ld) => reduction: ",
op->frames_filtered, op->frames_abs);
reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
(reduction == 100)?"near ":"", reduction);
if (len > PAGE_SIZE - 200) {
/* mark output cut off */
len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
break;
}
}
list_for_each_entry(op, &bo->tx_ops, list) {
len += snprintf(page + len, PAGE_SIZE - len,
"tx_op: %03X %s [%d] ",
op->can_id, bcm_proc_getifname(op->ifindex),
op->nframes);
if (op->kt_ival1.tv64)
len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ",
(long long) ktime_to_us(op->kt_ival1));
if (op->kt_ival2.tv64)
len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ",
(long long) ktime_to_us(op->kt_ival2));
len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
op->frames_abs);
if (len > PAGE_SIZE - 100) {
/* mark output cut off */
len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
break;
}
}
len += snprintf(page + len, PAGE_SIZE - len, "\n");
*eof = 1;
return len;
}
/*
* bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
* of the given bcm tx op
*/
static void bcm_can_tx(struct bcm_op *op)
{
struct sk_buff *skb;
struct net_device *dev;
struct can_frame *cf = &op->frames[op->currframe];
/* no target device? => exit */
if (!op->ifindex)
return;
dev = dev_get_by_index(&init_net, op->ifindex);
if (!dev) {
/* RFC: should this bcm_op remove itself here? */
return;
}
skb = alloc_skb(CFSIZ, gfp_any());
if (!skb)
goto out;
memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
/* send with loopback */
skb->dev = dev;
skb->sk = op->sk;
can_send(skb, 1);
/* update statistics */
op->currframe++;
op->frames_abs++;
/* reached last frame? */
if (op->currframe >= op->nframes)
op->currframe = 0;
out:
dev_put(dev);
}
/*
* bcm_send_to_user - send a BCM message to the userspace
* (consisting of bcm_msg_head + x CAN frames)
*/
static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
struct can_frame *frames, int has_timestamp)
{
struct sk_buff *skb;
struct can_frame *firstframe;
struct sockaddr_can *addr;
struct sock *sk = op->sk;
int datalen = head->nframes * CFSIZ;
int err;
skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
if (!skb)
return;
memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
if (head->nframes) {
/* can_frames starting here */
firstframe = (struct can_frame *)skb_tail_pointer(skb);
memcpy(skb_put(skb, datalen), frames, datalen);
/*
* the BCM uses the can_dlc-element of the can_frame
* structure for internal purposes. This is only
* relevant for updates that are generated by the
* BCM, where nframes is 1
*/
if (head->nframes == 1)
firstframe->can_dlc &= BCM_CAN_DLC_MASK;
}
if (has_timestamp) {
/* restore rx timestamp */
skb->tstamp = op->rx_stamp;
}
/*
* Put the datagram to the queue so that bcm_recvmsg() can
* get it from there. We need to pass the interface index to
* bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
* containing the interface index.
*/
BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
addr = (struct sockaddr_can *)skb->cb;
memset(addr, 0, sizeof(*addr));
addr->can_family = AF_CAN;
addr->can_ifindex = op->rx_ifindex;
err = sock_queue_rcv_skb(sk, skb);
if (err < 0) {
struct bcm_sock *bo = bcm_sk(sk);
kfree_skb(skb);
/* don't care about overflows in this statistic */
bo->dropped_usr_msgs++;
}
}
static void bcm_tx_timeout_tsklet(unsigned long data)
{
struct bcm_op *op = (struct bcm_op *)data;
struct bcm_msg_head msg_head;
/* create notification to user */
msg_head.opcode = TX_EXPIRED;
msg_head.flags = op->flags;
msg_head.count = op->count;
msg_head.ival1 = op->ival1;
msg_head.ival2 = op->ival2;
msg_head.can_id = op->can_id;
msg_head.nframes = 0;
bcm_send_to_user(op, &msg_head, NULL, 0);
}
/*
* bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
*/
static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
{
struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
enum hrtimer_restart ret = HRTIMER_NORESTART;
if (op->kt_ival1.tv64 && (op->count > 0)) {
op->count--;
if (!op->count && (op->flags & TX_COUNTEVT))
tasklet_schedule(&op->tsklet);
}
if (op->kt_ival1.tv64 && (op->count > 0)) {
/* send (next) frame */
bcm_can_tx(op);
hrtimer_forward(hrtimer, ktime_get(), op->kt_ival1);
ret = HRTIMER_RESTART;
} else {
if (op->kt_ival2.tv64) {
/* send (next) frame */
bcm_can_tx(op);
hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
ret = HRTIMER_RESTART;
}
}
return ret;
}
/*
* bcm_rx_changed - create a RX_CHANGED notification due to changed content
*/
static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
{
struct bcm_msg_head head;
/* update statistics */
op->frames_filtered++;
/* prevent statistics overflow */
if (op->frames_filtered > ULONG_MAX/100)
op->frames_filtered = op->frames_abs = 0;
/* this element is not throttled anymore */
data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
head.opcode = RX_CHANGED;
head.flags = op->flags;
head.count = op->count;
head.ival1 = op->ival1;
head.ival2 = op->ival2;
head.can_id = op->can_id;
head.nframes = 1;
bcm_send_to_user(op, &head, data, 1);
}
/*
* bcm_rx_update_and_send - process a detected relevant receive content change
* 1. update the last received data
* 2. send a notification to the user (if possible)
*/
static void bcm_rx_update_and_send(struct bcm_op *op,
struct can_frame *lastdata,
const struct can_frame *rxdata)
{
memcpy(lastdata, rxdata, CFSIZ);
/* mark as used and throttled by default */
lastdata->can_dlc |= (RX_RECV|RX_THR);
/* throtteling mode inactive ? */
if (!op->kt_ival2.tv64) {
/* send RX_CHANGED to the user immediately */
bcm_rx_changed(op, lastdata);
return;
}
/* with active throttling timer we are just done here */
if (hrtimer_active(&op->thrtimer))
return;
/* first receiption with enabled throttling mode */
if (!op->kt_lastmsg.tv64)
goto rx_changed_settime;
/* got a second frame inside a potential throttle period? */
if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
ktime_to_us(op->kt_ival2)) {
/* do not send the saved data - only start throttle timer */
hrtimer_start(&op->thrtimer,
ktime_add(op->kt_lastmsg, op->kt_ival2),
HRTIMER_MODE_ABS);
return;
}
/* the gap was that big, that throttling was not needed here */
rx_changed_settime:
bcm_rx_changed(op, lastdata);
op->kt_lastmsg = ktime_get();
}
/*
* bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
* received data stored in op->last_frames[]
*/
static void bcm_rx_cmp_to_index(struct bcm_op *op, int index,
const struct can_frame *rxdata)
{
/*
* no one uses the MSBs of can_dlc for comparation,
* so we use it here to detect the first time of reception
*/
if (!(op->last_frames[index].can_dlc & RX_RECV)) {
/* received data for the first time => send update to user */
bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
return;
}
/* do a real check in can_frame data section */
if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
(GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
return;
}
if (op->flags & RX_CHECK_DLC) {
/* do a real check in can_frame dlc */
if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
BCM_CAN_DLC_MASK)) {
bcm_rx_update_and_send(op, &op->last_frames[index],
rxdata);
return;
}
}
}
/*
* bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
*/
static void bcm_rx_starttimer(struct bcm_op *op)
{
if (op->flags & RX_NO_AUTOTIMER)
return;
if (op->kt_ival1.tv64)
hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
}
static void bcm_rx_timeout_tsklet(unsigned long data)
{
struct bcm_op *op = (struct bcm_op *)data;
struct bcm_msg_head msg_head;
/* create notification to user */
msg_head.opcode = RX_TIMEOUT;
msg_head.flags = op->flags;
msg_head.count = op->count;
msg_head.ival1 = op->ival1;
msg_head.ival2 = op->ival2;
msg_head.can_id = op->can_id;
msg_head.nframes = 0;
bcm_send_to_user(op, &msg_head, NULL, 0);
}
/*
* bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
*/
static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
{
struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
/* schedule before NET_RX_SOFTIRQ */
tasklet_hi_schedule(&op->tsklet);
/* no restart of the timer is done here! */
/* if user wants to be informed, when cyclic CAN-Messages come back */
if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
/* clear received can_frames to indicate 'nothing received' */
memset(op->last_frames, 0, op->nframes * CFSIZ);
}
return HRTIMER_NORESTART;
}
/*
* bcm_rx_do_flush - helper for bcm_rx_thr_flush
*/
static inline int bcm_rx_do_flush(struct bcm_op *op, int update, int index)
{
if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
if (update)
bcm_rx_changed(op, &op->last_frames[index]);
return 1;
}
return 0;
}
/*
* bcm_rx_thr_flush - Check for throttled data and send it to the userspace
*
* update == 0 : just check if throttled data is available (any irq context)
* update == 1 : check and send throttled data to userspace (soft_irq context)
*/
static int bcm_rx_thr_flush(struct bcm_op *op, int update)
{
int updated = 0;
if (op->nframes > 1) {
int i;
/* for MUX filter we start at index 1 */
for (i = 1; i < op->nframes; i++)
updated += bcm_rx_do_flush(op, update, i);
} else {
/* for RX_FILTER_ID and simple filter */
updated += bcm_rx_do_flush(op, update, 0);
}
return updated;
}
static void bcm_rx_thr_tsklet(unsigned long data)
{
struct bcm_op *op = (struct bcm_op *)data;
/* push the changed data to the userspace */
bcm_rx_thr_flush(op, 1);
}
/*
* bcm_rx_thr_handler - the time for blocked content updates is over now:
* Check for throttled data and send it to the userspace
*/
static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
{
struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
tasklet_schedule(&op->thrtsklet);
if (bcm_rx_thr_flush(op, 0)) {
hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
return HRTIMER_RESTART;
} else {
/* rearm throttle handling */
op->kt_lastmsg = ktime_set(0, 0);
return HRTIMER_NORESTART;
}
}
/*
* bcm_rx_handler - handle a CAN frame receiption
*/
static void bcm_rx_handler(struct sk_buff *skb, void *data)
{
struct bcm_op *op = (struct bcm_op *)data;
const struct can_frame *rxframe = (struct can_frame *)skb->data;
int i;
/* disable timeout */
hrtimer_cancel(&op->timer);
if (op->can_id != rxframe->can_id)
goto rx_freeskb;
/* save rx timestamp */
op->rx_stamp = skb->tstamp;
/* save originator for recvfrom() */
op->rx_ifindex = skb->dev->ifindex;
/* update statistics */
op->frames_abs++;
if (op->flags & RX_RTR_FRAME) {
/* send reply for RTR-request (placed in op->frames[0]) */
bcm_can_tx(op);
goto rx_freeskb;
}
if (op->flags & RX_FILTER_ID) {
/* the easiest case */
bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
goto rx_freeskb_starttimer;
}
if (op->nframes == 1) {
/* simple compare with index 0 */
bcm_rx_cmp_to_index(op, 0, rxframe);
goto rx_freeskb_starttimer;
}
if (op->nframes > 1) {
/*
* multiplex compare
*
* find the first multiplex mask that fits.
* Remark: The MUX-mask is stored in index 0
*/
for (i = 1; i < op->nframes; i++) {
if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
(GET_U64(&op->frames[0]) &
GET_U64(&op->frames[i]))) {
bcm_rx_cmp_to_index(op, i, rxframe);
break;
}
}
}
rx_freeskb_starttimer:
bcm_rx_starttimer(op);
rx_freeskb:
kfree_skb(skb);
}
/*
* helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
*/
static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
int ifindex)
{
struct bcm_op *op;
list_for_each_entry(op, ops, list) {
if ((op->can_id == can_id) && (op->ifindex == ifindex))
return op;
}
return NULL;
}
static void bcm_remove_op(struct bcm_op *op)
{
hrtimer_cancel(&op->timer);
hrtimer_cancel(&op->thrtimer);
if (op->tsklet.func)
tasklet_kill(&op->tsklet);
if (op->thrtsklet.func)
tasklet_kill(&op->thrtsklet);
if ((op->frames) && (op->frames != &op->sframe))
kfree(op->frames);
if ((op->last_frames) && (op->last_frames != &op->last_sframe))
kfree(op->last_frames);
kfree(op);
return;
}
static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
{
if (op->rx_reg_dev == dev) {
can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
bcm_rx_handler, op);
/* mark as removed subscription */
op->rx_reg_dev = NULL;
} else
printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
"mismatch %p %p\n", op->rx_reg_dev, dev);
}
/*
* bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
*/
static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
{
struct bcm_op *op, *n;
list_for_each_entry_safe(op, n, ops, list) {
if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
/*
* Don't care if we're bound or not (due to netdev
* problems) can_rx_unregister() is always a save
* thing to do here.
*/
if (op->ifindex) {
/*
* Only remove subscriptions that had not
* been removed due to NETDEV_UNREGISTER
* in bcm_notifier()
*/
if (op->rx_reg_dev) {
struct net_device *dev;
dev = dev_get_by_index(&init_net,
op->ifindex);
if (dev) {
bcm_rx_unreg(dev, op);
dev_put(dev);
}
}
} else
can_rx_unregister(NULL, op->can_id,
REGMASK(op->can_id),
bcm_rx_handler, op);
list_del(&op->list);
bcm_remove_op(op);
return 1; /* done */
}
}
return 0; /* not found */
}
/*
* bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
*/
static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
{
struct bcm_op *op, *n;
list_for_each_entry_safe(op, n, ops, list) {
if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
list_del(&op->list);
bcm_remove_op(op);
return 1; /* done */
}
}
return 0; /* not found */
}
/*
* bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
*/
static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
int ifindex)
{
struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
if (!op)
return -EINVAL;
/* put current values into msg_head */
msg_head->flags = op->flags;
msg_head->count = op->count;
msg_head->ival1 = op->ival1;
msg_head->ival2 = op->ival2;
msg_head->nframes = op->nframes;
bcm_send_to_user(op, msg_head, op->frames, 0);
return MHSIZ;
}
/*
* bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
*/
static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
int ifindex, struct sock *sk)
{
struct bcm_sock *bo = bcm_sk(sk);
struct bcm_op *op;
int i, err;
/* we need a real device to send frames */
if (!ifindex)
return -ENODEV;
/* we need at least one can_frame */
if (msg_head->nframes < 1)
return -EINVAL;
/* check the given can_id */
op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
if (op) {
/* update existing BCM operation */
/*
* Do we need more space for the can_frames than currently
* allocated? -> This is a _really_ unusual use-case and
* therefore (complexity / locking) it is not supported.
*/
if (msg_head->nframes > op->nframes)
return -E2BIG;
/* update can_frames content */
for (i = 0; i < msg_head->nframes; i++) {
err = memcpy_fromiovec((u8 *)&op->frames[i],
msg->msg_iov, CFSIZ);
if (op->frames[i].can_dlc > 8)
err = -EINVAL;
if (err < 0)
return err;
if (msg_head->flags & TX_CP_CAN_ID) {
/* copy can_id into frame */
op->frames[i].can_id = msg_head->can_id;
}
}
} else {
/* insert new BCM operation for the given can_id */
op = kzalloc(OPSIZ, GFP_KERNEL);
if (!op)
return -ENOMEM;
op->can_id = msg_head->can_id;
/* create array for can_frames and copy the data */
if (msg_head->nframes > 1) {
op->frames = kmalloc(msg_head->nframes * CFSIZ,
GFP_KERNEL);
if (!op->frames) {
kfree(op);
return -ENOMEM;
}
} else
op->frames = &op->sframe;
for (i = 0; i < msg_head->nframes; i++) {
err = memcpy_fromiovec((u8 *)&op->frames[i],
msg->msg_iov, CFSIZ);
if (op->frames[i].can_dlc > 8)
err = -EINVAL;
if (err < 0) {
if (op->frames != &op->sframe)
kfree(op->frames);
kfree(op);
return err;
}
if (msg_head->flags & TX_CP_CAN_ID) {
/* copy can_id into frame */
op->frames[i].can_id = msg_head->can_id;
}
}
/* tx_ops never compare with previous received messages */
op->last_frames = NULL;
/* bcm_can_tx / bcm_tx_timeout_handler needs this */
op->sk = sk;
op->ifindex = ifindex;
/* initialize uninitialized (kzalloc) structure */
hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
op->timer.function = bcm_tx_timeout_handler;
/* initialize tasklet for tx countevent notification */
tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
(unsigned long) op);
/* currently unused in tx_ops */
hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
/* add this bcm_op to the list of the tx_ops */
list_add(&op->list, &bo->tx_ops);
} /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
if (op->nframes != msg_head->nframes) {
op->nframes = msg_head->nframes;
/* start multiple frame transmission with index 0 */
op->currframe = 0;
}
/* check flags */
op->flags = msg_head->flags;
if (op->flags & TX_RESET_MULTI_IDX) {
/* start multiple frame transmission with index 0 */
op->currframe = 0;
}
if (op->flags & SETTIMER) {
/* set timer values */
op->count = msg_head->count;
op->ival1 = msg_head->ival1;
op->ival2 = msg_head->ival2;
op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
/* disable an active timer due to zero values? */
if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
hrtimer_cancel(&op->timer);
}
if ((op->flags & STARTTIMER) &&
((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) {
/* spec: send can_frame when starting timer */
op->flags |= TX_ANNOUNCE;
if (op->kt_ival1.tv64 && (op->count > 0)) {
/* op->count-- is done in bcm_tx_timeout_handler */
hrtimer_start(&op->timer, op->kt_ival1,
HRTIMER_MODE_REL);
} else
hrtimer_start(&op->timer, op->kt_ival2,
HRTIMER_MODE_REL);
}
if (op->flags & TX_ANNOUNCE)
bcm_can_tx(op);
return msg_head->nframes * CFSIZ + MHSIZ;
}
/*
* bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
*/
static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
int ifindex, struct sock *sk)
{
struct bcm_sock *bo = bcm_sk(sk);
struct bcm_op *op;
int do_rx_register;
int err = 0;
if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
/* be robust against wrong usage ... */
msg_head->flags |= RX_FILTER_ID;
/* ignore trailing garbage */
msg_head->nframes = 0;