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ffd980f9
OH		 1/*
2 * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content
3 *
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of Volkswagen nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * Alternatively, provided that this notice is retained in full, this
20 * software may be distributed under the terms of the GNU General
21 * Public License ("GPL") version 2, in which case the provisions of the
22 * GPL apply INSTEAD OF those given above.
23 *
24 * The provided data structures and external interfaces from this code
25 * are not restricted to be used by modules with a GPL compatible license.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
38 * DAMAGE.
39 *
40 * Send feedback to <socketcan-users@lists.berlios.de>
41 *
42 */
43
44#include <linux/module.h>
45#include <linux/init.h>
46#include <linux/list.h>
47#include <linux/proc_fs.h>
48#include <linux/uio.h>
49#include <linux/net.h>
50#include <linux/netdevice.h>
51#include <linux/socket.h>
52#include <linux/if_arp.h>
53#include <linux/skbuff.h>
54#include <linux/can.h>
55#include <linux/can/core.h>
56#include <linux/can/bcm.h>
57#include <net/sock.h>
58#include <net/net_namespace.h>
59
60/* use of last_frames[index].can_dlc */
61#define RX_RECV 0x40 /* received data for this element */
62#define RX_THR 0x80 /* element not been sent due to throttle feature */
63#define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
64
65/* get best masking value for can_rx_register() for a given single can_id */
66#define REGMASK(id) ((id & CAN_RTR_FLAG) | ((id & CAN_EFF_FLAG) ? \
67 (CAN_EFF_MASK | CAN_EFF_FLAG) : CAN_SFF_MASK))
68
69#define CAN_BCM_VERSION CAN_VERSION
70static __initdata const char banner[] = KERN_INFO
71 "can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n";
72
73MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
74MODULE_LICENSE("Dual BSD/GPL");
75MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
76
77/* easy access to can_frame payload */
78static inline u64 GET_U64(const struct can_frame *cp)
79{
80 return *(u64 *)cp->data;
81}
82
83struct bcm_op {
84 struct list_head list;
85 int ifindex;
86 canid_t can_id;
87 int flags;
88 unsigned long j_ival1, j_ival2, j_lastmsg;
89 unsigned long frames_abs, frames_filtered;
90 struct timer_list timer, thrtimer;
91 struct timeval ival1, ival2;
92 ktime_t rx_stamp;
93 int rx_ifindex;
94 int count;
95 int nframes;
96 int currframe;
97 struct can_frame *frames;
98 struct can_frame *last_frames;
99 struct can_frame sframe;
100 struct can_frame last_sframe;
101 struct sock *sk;
102 struct net_device *rx_reg_dev;
103};
104
105static struct proc_dir_entry *proc_dir;
106
107struct bcm_sock {
108 struct sock sk;
109 int bound;
110 int ifindex;
111 struct notifier_block notifier;
112 struct list_head rx_ops;
113 struct list_head tx_ops;
114 unsigned long dropped_usr_msgs;
115 struct proc_dir_entry *bcm_proc_read;
116 char procname [9]; /* pointer printed in ASCII with \0 */
117};
118
119static inline struct bcm_sock *bcm_sk(const struct sock *sk)
120{
121 return (struct bcm_sock *)sk;
122}
123
124#define CFSIZ sizeof(struct can_frame)
125#define OPSIZ sizeof(struct bcm_op)
126#define MHSIZ sizeof(struct bcm_msg_head)
127
128/*
129 * rounded_tv2jif - calculate jiffies from timeval including optional up
130 * @tv: pointer to timeval
131 *
132 * Description:
133 * Unlike timeval_to_jiffies() provided in include/linux/jiffies.h, this
134 * function is intentionally more relaxed on precise timer ticks to get
135 * exact one jiffy for requested 1000us on a 1000HZ machine.
136 * This code is to be removed when upgrading to kernel hrtimer.
137 *
138 * Return:
139 * calculated jiffies (max: ULONG_MAX)
140 */
141static unsigned long rounded_tv2jif(const struct timeval *tv)
142{
143 unsigned long sec = tv->tv_sec;
144 unsigned long usec = tv->tv_usec;
145 unsigned long jif;
146
147 if (sec > ULONG_MAX / HZ)
148 return ULONG_MAX;
149
150 /* round up to get at least the requested time */
151 usec += 1000000 / HZ - 1;
152
153 jif = usec / (1000000 / HZ);
154
155 if (sec * HZ > ULONG_MAX - jif)
156 return ULONG_MAX;
157
158 return jif + sec * HZ;
159}
160
161/*
162 * procfs functions
163 */
164static char *bcm_proc_getifname(int ifindex)
165{
166 struct net_device *dev;
167
168 if (!ifindex)
169 return "any";
170
171 /* no usage counting */
172 dev = __dev_get_by_index(&init_net, ifindex);
173 if (dev)
174 return dev->name;
175
176 return "???";
177}
178
179static int bcm_read_proc(char *page, char **start, off_t off,
180 int count, int *eof, void *data)
181{
182 int len = 0;
183 struct sock *sk = (struct sock *)data;
184 struct bcm_sock *bo = bcm_sk(sk);
185 struct bcm_op *op;
186
187 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
188 sk->sk_socket);
189 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
190 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
191 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
192 bo->dropped_usr_msgs);
193 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
194 bcm_proc_getifname(bo->ifindex));
195 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n");
196
197 list_for_each_entry(op, &bo->rx_ops, list) {
198
199 unsigned long reduction;
200
201 /* print only active entries & prevent division by zero */
202 if (!op->frames_abs)
203 continue;
204
205 len += snprintf(page + len, PAGE_SIZE - len,
206 "rx_op: %03X %-5s ",
207 op->can_id, bcm_proc_getifname(op->ifindex));
208 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
209 op->nframes,
210 (op->flags & RX_CHECK_DLC)?'d':' ');
211 if (op->j_ival1)
212 len += snprintf(page + len, PAGE_SIZE - len,
213 "timeo=%ld ", op->j_ival1);
214
215 if (op->j_ival2)
216 len += snprintf(page + len, PAGE_SIZE - len,
217 "thr=%ld ", op->j_ival2);
218
219 len += snprintf(page + len, PAGE_SIZE - len,
220 "# recv %ld (%ld) => reduction: ",
221 op->frames_filtered, op->frames_abs);
222
223 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
224
225 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
226 (reduction == 100)?"near ":"", reduction);
227
228 if (len > PAGE_SIZE - 200) {
229 /* mark output cut off */
230 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
231 break;
232 }
233 }
234
235 list_for_each_entry(op, &bo->tx_ops, list) {
236
237 len += snprintf(page + len, PAGE_SIZE - len,
238 "tx_op: %03X %s [%d] ",
239 op->can_id, bcm_proc_getifname(op->ifindex),
240 op->nframes);
241 if (op->j_ival1)
242 len += snprintf(page + len, PAGE_SIZE - len, "t1=%ld ",
243 op->j_ival1);
244
245 if (op->j_ival2)
246 len += snprintf(page + len, PAGE_SIZE - len, "t2=%ld ",
247 op->j_ival2);
248
249 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
250 op->frames_abs);
251
252 if (len > PAGE_SIZE - 100) {
253 /* mark output cut off */
254 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
255 break;
256 }
257 }
258
259 len += snprintf(page + len, PAGE_SIZE - len, "\n");
260
261 *eof = 1;
262 return len;
263}
264
265/*
266 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
267 * of the given bcm tx op
268 */
269static void bcm_can_tx(struct bcm_op *op)
270{
271 struct sk_buff *skb;
272 struct net_device *dev;
273 struct can_frame *cf = &op->frames[op->currframe];
274
275 /* no target device? => exit */
276 if (!op->ifindex)
277 return;
278
279 dev = dev_get_by_index(&init_net, op->ifindex);
280 if (!dev) {
281 /* RFC: should this bcm_op remove itself here? */
282 return;
283 }
284
285 skb = alloc_skb(CFSIZ, gfp_any());
286 if (!skb)
287 goto out;
288
289 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
290
291 /* send with loopback */
292 skb->dev = dev;
293 skb->sk = op->sk;
294 can_send(skb, 1);
295
296 /* update statistics */
297 op->currframe++;
298 op->frames_abs++;
299
300 /* reached last frame? */
301 if (op->currframe >= op->nframes)
302 op->currframe = 0;
303 out:
304 dev_put(dev);
305}
306
307/*
308 * bcm_send_to_user - send a BCM message to the userspace
309 * (consisting of bcm_msg_head + x CAN frames)
310 */
311static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
312 struct can_frame *frames, int has_timestamp)
313{
314 struct sk_buff *skb;
315 struct can_frame *firstframe;
316 struct sockaddr_can *addr;
317 struct sock *sk = op->sk;
318 int datalen = head->nframes * CFSIZ;
319 int err;
320
321 skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
322 if (!skb)
323 return;
324
325 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
326
327 if (head->nframes) {
328 /* can_frames starting here */
329 firstframe = (struct can_frame *) skb_tail_pointer(skb);
330
331 memcpy(skb_put(skb, datalen), frames, datalen);
332
333 /*
334 * the BCM uses the can_dlc-element of the can_frame
335 * structure for internal purposes. This is only
336 * relevant for updates that are generated by the
337 * BCM, where nframes is 1
338 */
339 if (head->nframes == 1)
340 firstframe->can_dlc &= BCM_CAN_DLC_MASK;
341 }
342
343 if (has_timestamp) {
344 /* restore rx timestamp */
345 skb->tstamp = op->rx_stamp;
346 }
347
348 /*
349 * Put the datagram to the queue so that bcm_recvmsg() can
350 * get it from there. We need to pass the interface index to
351 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
352 * containing the interface index.
353 */
354
355 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
356 addr = (struct sockaddr_can *)skb->cb;
357 memset(addr, 0, sizeof(*addr));
358 addr->can_family = AF_CAN;
359 addr->can_ifindex = op->rx_ifindex;
360
361 err = sock_queue_rcv_skb(sk, skb);
362 if (err < 0) {
363 struct bcm_sock *bo = bcm_sk(sk);
364
365 kfree_skb(skb);
366 /* don't care about overflows in this statistic */
367 bo->dropped_usr_msgs++;
368 }
369}
370
371/*
372 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
373 */
374static void bcm_tx_timeout_handler(unsigned long data)
375{
376 struct bcm_op *op = (struct bcm_op *)data;
377
378 if (op->j_ival1 && (op->count > 0)) {
379
380 op->count--;
381 if (!op->count && (op->flags & TX_COUNTEVT)) {
382 struct bcm_msg_head msg_head;
383
384 /* create notification to user */
385 msg_head.opcode = TX_EXPIRED;
386 msg_head.flags = op->flags;
387 msg_head.count = op->count;
388 msg_head.ival1 = op->ival1;
389 msg_head.ival2 = op->ival2;
390 msg_head.can_id = op->can_id;
391 msg_head.nframes = 0;
392
393 bcm_send_to_user(op, &msg_head, NULL, 0);
394 }
395 }
396
397 if (op->j_ival1 && (op->count > 0)) {
398
399 /* send (next) frame */
400 bcm_can_tx(op);
401 mod_timer(&op->timer, jiffies + op->j_ival1);
402
403 } else {
404 if (op->j_ival2) {
405
406 /* send (next) frame */
407 bcm_can_tx(op);
408 mod_timer(&op->timer, jiffies + op->j_ival2);
409 }
410 }
411
412 return;
413}
414
415/*
416 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
417 */
418static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
419{
420 struct bcm_msg_head head;
421
422 op->j_lastmsg = jiffies;
423
424 /* update statistics */
425 op->frames_filtered++;
426
427 /* prevent statistics overflow */
428 if (op->frames_filtered > ULONG_MAX/100)
429 op->frames_filtered = op->frames_abs = 0;
430
431 head.opcode = RX_CHANGED;
432 head.flags = op->flags;
433 head.count = op->count;
434 head.ival1 = op->ival1;
435 head.ival2 = op->ival2;
436 head.can_id = op->can_id;
437 head.nframes = 1;
438
439 bcm_send_to_user(op, &head, data, 1);
440}
441
442/*
443 * bcm_rx_update_and_send - process a detected relevant receive content change
444 * 1. update the last received data
445 * 2. send a notification to the user (if possible)
446 */
447static void bcm_rx_update_and_send(struct bcm_op *op,
448 struct can_frame *lastdata,
449 struct can_frame *rxdata)
450{
451 unsigned long nexttx = op->j_lastmsg + op->j_ival2;
452
453 memcpy(lastdata, rxdata, CFSIZ);
454
455 /* mark as used */
456 lastdata->can_dlc |= RX_RECV;
457
458 /* throttle bcm_rx_changed ? */
459 if ((op->thrtimer.expires) ||
460 ((op->j_ival2) && (nexttx > jiffies))) {
461 /* we are already waiting OR we have to start waiting */
462
463 /* mark as 'throttled' */
464 lastdata->can_dlc |= RX_THR;
465
466 if (!(op->thrtimer.expires)) {
467 /* start the timer only the first time */
468 mod_timer(&op->thrtimer, nexttx);
469 }
470
471 } else {
472 /* send RX_CHANGED to the user immediately */
473 bcm_rx_changed(op, rxdata);
474 }
475}
476
477/*
478 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
479 * received data stored in op->last_frames[]
480 */
481static void bcm_rx_cmp_to_index(struct bcm_op *op, int index,
482 struct can_frame *rxdata)
483{
484 /*
485 * no one uses the MSBs of can_dlc for comparation,
486 * so we use it here to detect the first time of reception
487 */
488
489 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
490 /* received data for the first time => send update to user */
491 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
492 return;
493 }
494
495 /* do a real check in can_frame data section */
496
497 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
498 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
499 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
500 return;
501 }
502
503 if (op->flags & RX_CHECK_DLC) {
504 /* do a real check in can_frame dlc */
505 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
506 BCM_CAN_DLC_MASK)) {
507 bcm_rx_update_and_send(op, &op->last_frames[index],
508 rxdata);
509 return;
510 }
511 }
512}
513
514/*
515 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
516 */
517static void bcm_rx_starttimer(struct bcm_op *op)
518{
519 if (op->flags & RX_NO_AUTOTIMER)
520 return;
521
522 if (op->j_ival1)
523 mod_timer(&op->timer, jiffies + op->j_ival1);
524}
525
526/*
527 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
528 */
529static void bcm_rx_timeout_handler(unsigned long data)
530{
531 struct bcm_op *op = (struct bcm_op *)data;
532 struct bcm_msg_head msg_head;
533
534 msg_head.opcode = RX_TIMEOUT;
535 msg_head.flags = op->flags;
536 msg_head.count = op->count;
537 msg_head.ival1 = op->ival1;
538 msg_head.ival2 = op->ival2;
539 msg_head.can_id = op->can_id;
540 msg_head.nframes = 0;
541
542 bcm_send_to_user(op, &msg_head, NULL, 0);
543
544 /* no restart of the timer is done here! */
545
546 /* if user wants to be informed, when cyclic CAN-Messages come back */
547 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
548 /* clear received can_frames to indicate 'nothing received' */
549 memset(op->last_frames, 0, op->nframes * CFSIZ);
550 }
551}
552
553/*
554 * bcm_rx_thr_handler - the time for blocked content updates is over now:
555 * Check for throttled data and send it to the userspace
556 */
557static void bcm_rx_thr_handler(unsigned long data)
558{
559 struct bcm_op *op = (struct bcm_op *)data;
560 int i = 0;
561
562 /* mark disabled / consumed timer */
563 op->thrtimer.expires = 0;
564
565 if (op->nframes > 1) {
566 /* for MUX filter we start at index 1 */
567 for (i = 1; i < op->nframes; i++) {
568 if ((op->last_frames) &&
569 (op->last_frames[i].can_dlc & RX_THR)) {
570 op->last_frames[i].can_dlc &= ~RX_THR;
571 bcm_rx_changed(op, &op->last_frames[i]);
572 }
573 }
574
575 } else {
576 /* for RX_FILTER_ID and simple filter */
577 if (op->last_frames && (op->last_frames[0].can_dlc & RX_THR)) {
578 op->last_frames[0].can_dlc &= ~RX_THR;
579 bcm_rx_changed(op, &op->last_frames[0]);
580 }
581 }
582}
583
584/*
585 * bcm_rx_handler - handle a CAN frame receiption
586 */
587static void bcm_rx_handler(struct sk_buff *skb, void *data)
588{
589 struct bcm_op *op = (struct bcm_op *)data;
590 struct can_frame rxframe;
591 int i;
592
593 /* disable timeout */
594 del_timer(&op->timer);
595
596 if (skb->len == sizeof(rxframe)) {
597 memcpy(&rxframe, skb->data, sizeof(rxframe));
598 /* save rx timestamp */
599 op->rx_stamp = skb->tstamp;
600 /* save originator for recvfrom() */
601 op->rx_ifindex = skb->dev->ifindex;
602 /* update statistics */
603 op->frames_abs++;
604 kfree_skb(skb);
605
606 } else {
607 kfree_skb(skb);
608 return;
609 }
610
611 if (op->can_id != rxframe.can_id)
612 return;
613
614 if (op->flags & RX_RTR_FRAME) {
615 /* send reply for RTR-request (placed in op->frames[0]) */
616 bcm_can_tx(op);
617 return;
618 }
619
620 if (op->flags & RX_FILTER_ID) {
621 /* the easiest case */
622 bcm_rx_update_and_send(op, &op->last_frames[0], &rxframe);
623 bcm_rx_starttimer(op);
624 return;
625 }
626
627 if (op->nframes == 1) {
628 /* simple compare with index 0 */
629 bcm_rx_cmp_to_index(op, 0, &rxframe);
630 bcm_rx_starttimer(op);
631 return;
632 }
633
634 if (op->nframes > 1) {
635 /*
636 * multiplex compare
637 *
638 * find the first multiplex mask that fits.
639 * Remark: The MUX-mask is stored in index 0
640 */
641
642 for (i = 1; i < op->nframes; i++) {
643 if ((GET_U64(&op->frames[0]) & GET_U64(&rxframe)) ==
644 (GET_U64(&op->frames[0]) &
645 GET_U64(&op->frames[i]))) {
646 bcm_rx_cmp_to_index(op, i, &rxframe);
647 break;
648 }
649 }
650 bcm_rx_starttimer(op);
651 }
652}
653
654/*
655 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
656 */
657static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
658 int ifindex)
659{
660 struct bcm_op *op;
661
662 list_for_each_entry(op, ops, list) {
663 if ((op->can_id == can_id) && (op->ifindex == ifindex))
664 return op;
665 }
666
667 return NULL;
668}
669
670static void bcm_remove_op(struct bcm_op *op)
671{
672 del_timer(&op->timer);
673 del_timer(&op->thrtimer);
674
675 if ((op->frames) && (op->frames != &op->sframe))
676 kfree(op->frames);
677
678 if ((op->last_frames) && (op->last_frames != &op->last_sframe))
679 kfree(op->last_frames);
680
681 kfree(op);
682
683 return;
684}
685
686static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
687{
688 if (op->rx_reg_dev == dev) {
689 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
690 bcm_rx_handler, op);
691
692 /* mark as removed subscription */
693 op->rx_reg_dev = NULL;
694 } else
695 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
696 "mismatch %p %p\n", op->rx_reg_dev, dev);
697}
698
699/*
700 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
701 */
702static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
703{
704 struct bcm_op *op, *n;
705
706 list_for_each_entry_safe(op, n, ops, list) {
707 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
708
709 /*
710 * Don't care if we're bound or not (due to netdev
711 * problems) can_rx_unregister() is always a save
712 * thing to do here.
713 */
714 if (op->ifindex) {
715 /*
716 * Only remove subscriptions that had not
717 * been removed due to NETDEV_UNREGISTER
718 * in bcm_notifier()
719 */
720 if (op->rx_reg_dev) {
721 struct net_device *dev;
722
723 dev = dev_get_by_index(&init_net,
724 op->ifindex);
725 if (dev) {
726 bcm_rx_unreg(dev, op);
727 dev_put(dev);
728 }
729 }
730 } else
731 can_rx_unregister(NULL, op->can_id,
732 REGMASK(op->can_id),
733 bcm_rx_handler, op);
734
735 list_del(&op->list);
736 bcm_remove_op(op);
737 return 1; /* done */
738 }
739 }
740
741 return 0; /* not found */
742}
743
744/*
745 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
746 */
747static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
748{
749 struct bcm_op *op, *n;
750
751 list_for_each_entry_safe(op, n, ops, list) {
752 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
753 list_del(&op->list);
754 bcm_remove_op(op);
755 return 1; /* done */
756 }
757 }
758
759 return 0; /* not found */
760}
761
762/*
763 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
764 */
765static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
766 int ifindex)
767{
768 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
769
770 if (!op)
771 return -EINVAL;
772
773 /* put current values into msg_head */
774 msg_head->flags = op->flags;
775 msg_head->count = op->count;
776 msg_head->ival1 = op->ival1;
777 msg_head->ival2 = op->ival2;
778 msg_head->nframes = op->nframes;
779
780 bcm_send_to_user(op, msg_head, op->frames, 0);
781
782 return MHSIZ;
783}
784
785/*
786 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
787 */
788static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
789 int ifindex, struct sock *sk)
790{
791 struct bcm_sock *bo = bcm_sk(sk);
792 struct bcm_op *op;
793 int i, err;
794
795 /* we need a real device to send frames */
796 if (!ifindex)
797 return -ENODEV;
798
799 /* we need at least one can_frame */
800 if (msg_head->nframes < 1)
801 return -EINVAL;
802
803 /* check the given can_id */
804 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
805
806 if (op) {
807 /* update existing BCM operation */
808
809 /*
810 * Do we need more space for the can_frames than currently
811 * allocated? -> This is a _really_ unusual use-case and
812 * therefore (complexity / locking) it is not supported.
813 */
814 if (msg_head->nframes > op->nframes)
815 return -E2BIG;
816
817 /* update can_frames content */
818 for (i = 0; i < msg_head->nframes; i++) {
819 err = memcpy_fromiovec((u8 *)&op->frames[i],
820 msg->msg_iov, CFSIZ);
821 if (err < 0)
822 return err;
823
824 if (msg_head->flags & TX_CP_CAN_ID) {
825 /* copy can_id into frame */
826 op->frames[i].can_id = msg_head->can_id;
827 }
828 }
829
830 } else {
831 /* insert new BCM operation for the given can_id */
832
833 op = kzalloc(OPSIZ, GFP_KERNEL);
834 if (!op)
835 return -ENOMEM;
836
837 op->can_id = msg_head->can_id;
838
839 /* create array for can_frames and copy the data */
840 if (msg_head->nframes > 1) {
841 op->frames = kmalloc(msg_head->nframes * CFSIZ,
842 GFP_KERNEL);
843 if (!op->frames) {
844 kfree(op);
845 return -ENOMEM;
846 }
847 } else
848 op->frames = &op->sframe;
849
850 for (i = 0; i < msg_head->nframes; i++) {
851 err = memcpy_fromiovec((u8 *)&op->frames[i],
852 msg->msg_iov, CFSIZ);
853 if (err < 0) {
854 if (op->frames != &op->sframe)
855 kfree(op->frames);
856 kfree(op);
857 return err;
858 }
859
860 if (msg_head->flags & TX_CP_CAN_ID) {
861 /* copy can_id into frame */
862 op->frames[i].can_id = msg_head->can_id;
863 }
864 }
865
866 /* tx_ops never compare with previous received messages */
867 op->last_frames = NULL;
868
869 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
870 op->sk = sk;
871 op->ifindex = ifindex;
872
873 /* initialize uninitialized (kzalloc) structure */
874 setup_timer(&op->timer, bcm_tx_timeout_handler,
875 (unsigned long)op);
876
877 /* currently unused in tx_ops */
878 init_timer(&op->thrtimer);
879
880 /* add this bcm_op to the list of the tx_ops */
881 list_add(&op->list, &bo->tx_ops);
882
883 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
884
885 if (op->nframes != msg_head->nframes) {
886 op->nframes = msg_head->nframes;
887 /* start multiple frame transmission with index 0 */
888 op->currframe = 0;
889 }
890
891 /* check flags */
892
893 op->flags = msg_head->flags;
894
895 if (op->flags & TX_RESET_MULTI_IDX) {
896 /* start multiple frame transmission with index 0 */
897 op->currframe = 0;
898 }
899
900 if (op->flags & SETTIMER) {
901 /* set timer values */
902 op->count = msg_head->count;
903 op->ival1 = msg_head->ival1;
904 op->ival2 = msg_head->ival2;
905 op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
906 op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
907
908 /* disable an active timer due to zero values? */
909 if (!op->j_ival1 && !op->j_ival2)
910 del_timer(&op->timer);
911 }
912
913 if ((op->flags & STARTTIMER) &&
914 ((op->j_ival1 && op->count) || op->j_ival2)) {
915
916 /* spec: send can_frame when starting timer */
917 op->flags |= TX_ANNOUNCE;
918
919 if (op->j_ival1 && (op->count > 0)) {
920 /* op->count-- is done in bcm_tx_timeout_handler */
921 mod_timer(&op->timer, jiffies + op->j_ival1);
922 } else
923 mod_timer(&op->timer, jiffies + op->j_ival2);
924 }
925
926 if (op->flags & TX_ANNOUNCE)
927 bcm_can_tx(op);
928
929 return msg_head->nframes * CFSIZ + MHSIZ;
930}
931
932/*
933 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
934 */
935static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
936 int ifindex, struct sock *sk)
937{
938 struct bcm_sock *bo = bcm_sk(sk);
939 struct bcm_op *op;
940 int do_rx_register;
941 int err = 0;
942
943 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
944 /* be robust against wrong usage ... */
945 msg_head->flags |= RX_FILTER_ID;
946 /* ignore trailing garbage */
947 msg_head->nframes = 0;
948 }
949
950 if ((msg_head->flags & RX_RTR_FRAME) &&
951 ((msg_head->nframes != 1) ||
952 (!(msg_head->can_id & CAN_RTR_FLAG))))
953 return -EINVAL;
954
955 /* check the given can_id */
956 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
957 if (op) {
958 /* update existing BCM operation */
959
960 /*
961 * Do we need more space for the can_frames than currently
962 * allocated? -> This is a _really_ unusual use-case and
963 * therefore (complexity / locking) it is not supported.
964 */
965 if (msg_head->nframes > op->nframes)
966 return -E2BIG;
967
968 if (msg_head->nframes) {
969 /* update can_frames content */
970 err = memcpy_fromiovec((u8 *)op->frames,
971 msg->msg_iov,
972 msg_head->nframes * CFSIZ);
973 if (err < 0)
974 return err;
975
976 /* clear last_frames to indicate 'nothing received' */
977 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
978 }
979
980 op->nframes = msg_head->nframes;
981
982 /* Only an update -> do not call can_rx_register() */
983 do_rx_register = 0;
984
985 } else {
986 /* insert new BCM operation for the given can_id */
987 op = kzalloc(OPSIZ, GFP_KERNEL);
988 if (!op)
989 return -ENOMEM;
990
991 op->can_id = msg_head->can_id;
992 op->nframes = msg_head->nframes;
993
994 if (msg_head->nframes > 1) {
995 /* create array for can_frames and copy the data */
996 op->frames = kmalloc(msg_head->nframes * CFSIZ,
997 GFP_KERNEL);
998 if (!op->frames) {
999 kfree(op);
1000 return -ENOMEM;
1001 }
1002
1003 /* create and init array for received can_frames */
1004 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1005 GFP_KERNEL);
1006 if (!op->last_frames) {
1007 kfree(op->frames);
1008 kfree(op);
1009 return -ENOMEM;
1010 }
1011
1012 } else {
1013 op->frames = &op->sframe;
1014 op->last_frames = &op->last_sframe;
1015 }
1016
1017 if (msg_head->nframes) {
1018 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1019 msg_head->nframes * CFSIZ);
1020 if (err < 0) {
1021 if (op->frames != &op->sframe)
1022 kfree(op->frames);
1023 if (op->last_frames != &op->last_sframe)
1024 kfree(op->last_frames);
1025 kfree(op);
1026 return err;
1027 }
1028 }
1029
1030 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1031 op->sk = sk;
1032 op->ifindex = ifindex;
1033
1034 /* initialize uninitialized (kzalloc) structure */
1035 setup_timer(&op->timer, bcm_rx_timeout_handler,
1036 (unsigned long)op);
1037
1038 /* init throttle timer for RX_CHANGED */
1039 setup_timer(&op->thrtimer, bcm_rx_thr_handler,
1040 (unsigned long)op);
1041
1042 /* mark disabled timer */
1043 op->thrtimer.expires = 0;
1044
1045 /* add this bcm_op to the list of the rx_ops */
1046 list_add(&op->list, &bo->rx_ops);
1047
1048 /* call can_rx_register() */
1049 do_rx_register = 1;
1050
1051 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1052
1053 /* check flags */
1054 op->flags = msg_head->flags;
1055
1056 if (op->flags & RX_RTR_FRAME) {
1057
1058 /* no timers in RTR-mode */
1059 del_timer(&op->thrtimer);
1060 del_timer(&op->timer);
1061
1062 /*
1063 * funny feature in RX(!)_SETUP only for RTR-mode:
1064 * copy can_id into frame BUT without RTR-flag to
1065 * prevent a full-load-loopback-test ... ;-]
1066 */
1067 if ((op->flags & TX_CP_CAN_ID) ||
1068 (op->frames[0].can_id == op->can_id))
1069 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1070
1071 } else {
1072 if (op->flags & SETTIMER) {
1073
1074 /* set timer value */
1075 op->ival1 = msg_head->ival1;
1076 op->ival2 = msg_head->ival2;
1077 op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
1078 op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
1079
1080 /* disable an active timer due to zero value? */
1081 if (!op->j_ival1)
1082 del_timer(&op->timer);
1083
1084 /* free currently blocked msgs ? */
1085 if (op->thrtimer.expires) {
1086 /* send blocked msgs hereafter */
1087 mod_timer(&op->thrtimer, jiffies + 2);
1088 }
1089
1090 /*
1091 * if (op->j_ival2) is zero, no (new) throttling
1092 * will happen. For details see functions
1093 * bcm_rx_update_and_send() and bcm_rx_thr_handler()
1094 */
1095 }
1096
1097 if ((op->flags & STARTTIMER) && op->j_ival1)
1098 mod_timer(&op->timer, jiffies + op->j_ival1);
1099 }
1100
1101 /* now we can register for can_ids, if we added a new bcm_op */
1102 if (do_rx_register) {
1103 if (ifindex) {
1104 struct net_device *dev;
1105
1106 dev = dev_get_by_index(&init_net, ifindex);
1107 if (dev) {
1108 err = can_rx_register(dev, op->can_id,
1109 REGMASK(op->can_id),
1110 bcm_rx_handler, op,
1111 "bcm");
1112
1113 op->rx_reg_dev = dev;
1114 dev_put(dev);
1115 }
1116
1117 } else
1118 err = can_rx_register(NULL, op->can_id,
1119 REGMASK(op->can_id),
1120 bcm_rx_handler, op, "bcm");
1121 if (err) {
1122 /* this bcm rx op is broken -> remove it */
1123 list_del(&op->list);
1124 bcm_remove_op(op);
1125 return err;
1126 }
1127 }
1128
1129 return msg_head->nframes * CFSIZ + MHSIZ;
1130}
1131
1132/*
1133 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1134 */
1135static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1136{
1137 struct sk_buff *skb;
1138 struct net_device *dev;
1139 int err;
1140
1141 /* we need a real device to send frames */
1142 if (!ifindex)
1143 return -ENODEV;
1144
1145 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1146
1147 if (!skb)
1148 return -ENOMEM;
1149
1150 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1151 if (err < 0) {
1152 kfree_skb(skb);
1153 return err;
1154 }
1155
1156 dev = dev_get_by_index(&init_net, ifindex);
1157 if (!dev) {
1158 kfree_skb(skb);
1159 return -ENODEV;
1160 }
1161
1162 skb->dev = dev;
1163 skb->sk = sk;
1164 can_send(skb, 1); /* send with loopback */
1165 dev_put(dev);
1166
1167 return CFSIZ + MHSIZ;
1168}
1169
1170/*
1171 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1172 */
1173static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1174 struct msghdr *msg, size_t size)
1175{
1176 struct sock *sk = sock->sk;
1177 struct bcm_sock *bo = bcm_sk(sk);
1178 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1179 struct bcm_msg_head msg_head;
1180 int ret; /* read bytes or error codes as return value */
1181
1182 if (!bo->bound)
1183 return -ENOTCONN;
1184
1185 /* check for alternative ifindex for this bcm_op */
1186
1187 if (!ifindex && msg->msg_name) {
1188 /* no bound device as default => check msg_name */
1189 struct sockaddr_can *addr =
1190 (struct sockaddr_can *)msg->msg_name;
1191
1192 if (addr->can_family != AF_CAN)
1193 return -EINVAL;
1194
1195 /* ifindex from sendto() */
1196 ifindex = addr->can_ifindex;
1197
1198 if (ifindex) {
1199 struct net_device *dev;
1200
1201 dev = dev_get_by_index(&init_net, ifindex);
1202 if (!dev)
1203 return -ENODEV;
1204
1205 if (dev->type != ARPHRD_CAN) {
1206 dev_put(dev);
1207 return -ENODEV;
1208 }
1209
1210 dev_put(dev);
1211 }
1212 }
1213
1214 /* read message head information */
1215
1216 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1217 if (ret < 0)
1218 return ret;
1219
1220 lock_sock(sk);
1221
1222 switch (msg_head.opcode) {
1223
1224 case TX_SETUP:
1225 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1226 break;
1227
1228 case RX_SETUP:
1229 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1230 break;
1231
1232 case TX_DELETE:
1233 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1234 ret = MHSIZ;
1235 else
1236 ret = -EINVAL;
1237 break;
1238
1239 case RX_DELETE:
1240 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1241 ret = MHSIZ;
1242 else
1243 ret = -EINVAL;
1244 break;
1245
1246 case TX_READ:
1247 /* reuse msg_head for the reply to TX_READ */
1248 msg_head.opcode = TX_STATUS;
1249 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1250 break;
1251
1252 case RX_READ:
1253 /* reuse msg_head for the reply to RX_READ */
1254 msg_head.opcode = RX_STATUS;
1255 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1256 break;
1257
1258 case TX_SEND:
1259 /* we need at least one can_frame */
1260 if (msg_head.nframes < 1)
1261 ret = -EINVAL;
1262 else
1263 ret = bcm_tx_send(msg, ifindex, sk);
1264 break;
1265
1266 default:
1267 ret = -EINVAL;
1268 break;
1269 }
1270
1271 release_sock(sk);
1272
1273 return ret;
1274}
1275
1276/*
1277 * notification handler for netdevice status changes
1278 */
1279static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1280 void *data)
1281{
1282 struct net_device *dev = (struct net_device *)data;
1283 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1284 struct sock *sk = &bo->sk;
1285 struct bcm_op *op;
1286 int notify_enodev = 0;
1287
c346dca1 1288 if (dev_net(dev) != &init_net)
ffd980f9
OH		 1289 return NOTIFY_DONE;
1290
1291 if (dev->type != ARPHRD_CAN)
1292 return NOTIFY_DONE;
1293
1294 switch (msg) {
1295
1296 case NETDEV_UNREGISTER:
1297 lock_sock(sk);
1298
1299 /* remove device specific receive entries */
1300 list_for_each_entry(op, &bo->rx_ops, list)
1301 if (op->rx_reg_dev == dev)
1302 bcm_rx_unreg(dev, op);
1303
1304 /* remove device reference, if this is our bound device */
1305 if (bo->bound && bo->ifindex == dev->ifindex) {
1306 bo->bound = 0;
1307 bo->ifindex = 0;
1308 notify_enodev = 1;
1309 }
1310
1311 release_sock(sk);
1312
1313 if (notify_enodev) {
1314 sk->sk_err = ENODEV;
1315 if (!sock_flag(sk, SOCK_DEAD))
1316 sk->sk_error_report(sk);
1317 }
1318 break;
1319
1320 case NETDEV_DOWN:
1321 if (bo->bound && bo->ifindex == dev->ifindex) {
1322 sk->sk_err = ENETDOWN;
1323 if (!sock_flag(sk, SOCK_DEAD))
1324 sk->sk_error_report(sk);
1325 }
1326 }
1327
1328 return NOTIFY_DONE;
1329}
1330
1331/*
1332 * initial settings for all BCM sockets to be set at socket creation time
1333 */
1334static int bcm_init(struct sock *sk)
1335{
1336 struct bcm_sock *bo = bcm_sk(sk);
1337
1338 bo->bound = 0;
1339 bo->ifindex = 0;
1340 bo->dropped_usr_msgs = 0;
1341 bo->bcm_proc_read = NULL;
1342
1343 INIT_LIST_HEAD(&bo->tx_ops);
1344 INIT_LIST_HEAD(&bo->rx_ops);
1345
1346 /* set notifier */
1347 bo->notifier.notifier_call = bcm_notifier;
1348
1349 register_netdevice_notifier(&bo->notifier);
1350
1351 return 0;
1352}
1353
1354/*
1355 * standard socket functions
1356 */
1357static int bcm_release(struct socket *sock)
1358{
1359 struct sock *sk = sock->sk;
1360 struct bcm_sock *bo = bcm_sk(sk);
1361 struct bcm_op *op, *next;
1362
1363 /* remove bcm_ops, timer, rx_unregister(), etc. */
1364
1365 unregister_netdevice_notifier(&bo->notifier);
1366
1367 lock_sock(sk);
1368
1369 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1370 bcm_remove_op(op);
1371
1372 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1373 /*
1374 * Don't care if we're bound or not (due to netdev problems)
1375 * can_rx_unregister() is always a save thing to do here.
1376 */
1377 if (op->ifindex) {
1378 /*
1379 * Only remove subscriptions that had not
1380 * been removed due to NETDEV_UNREGISTER
1381 * in bcm_notifier()
1382 */
1383 if (op->rx_reg_dev) {
1384 struct net_device *dev;
1385
1386 dev = dev_get_by_index(&init_net, op->ifindex);
1387 if (dev) {
1388 bcm_rx_unreg(dev, op);
1389 dev_put(dev);
1390 }
1391 }
1392 } else
1393 can_rx_unregister(NULL, op->can_id,
1394 REGMASK(op->can_id),
1395 bcm_rx_handler, op);
1396
1397 bcm_remove_op(op);
1398 }
1399
1400 /* remove procfs entry */
1401 if (proc_dir && bo->bcm_proc_read)
1402 remove_proc_entry(bo->procname, proc_dir);
1403
1404 /* remove device reference */
1405 if (bo->bound) {
1406 bo->bound = 0;
1407 bo->ifindex = 0;
1408 }
1409
1410 release_sock(sk);
1411 sock_put(sk);
1412
1413 return 0;
1414}
1415
1416static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1417 int flags)
1418{
1419 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1420 struct sock *sk = sock->sk;
1421 struct bcm_sock *bo = bcm_sk(sk);
1422
1423 if (bo->bound)
1424 return -EISCONN;
1425
1426 /* bind a device to this socket */
1427 if (addr->can_ifindex) {
1428 struct net_device *dev;
1429
1430 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1431 if (!dev)
1432 return -ENODEV;
1433
1434 if (dev->type != ARPHRD_CAN) {
1435 dev_put(dev);
1436 return -ENODEV;
1437 }
1438
1439 bo->ifindex = dev->ifindex;
1440 dev_put(dev);
1441
1442 } else {
1443 /* no interface reference for ifindex = 0 ('any' CAN device) */
1444 bo->ifindex = 0;
1445 }
1446
1447 bo->bound = 1;
1448
1449 if (proc_dir) {
1450 /* unique socket address as filename */
1451 sprintf(bo->procname, "%p", sock);
1452 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
1453 proc_dir,
1454 bcm_read_proc, sk);
1455 }
1456
1457 return 0;
1458}
1459
1460static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1461 struct msghdr *msg, size_t size, int flags)
1462{
1463 struct sock *sk = sock->sk;
1464 struct sk_buff *skb;
1465 int error = 0;
1466 int noblock;
1467 int err;
1468
1469 noblock = flags & MSG_DONTWAIT;
1470 flags &= ~MSG_DONTWAIT;
1471 skb = skb_recv_datagram(sk, flags, noblock, &error);
1472 if (!skb)
1473 return error;
1474
1475 if (skb->len < size)
1476 size = skb->len;
1477
1478 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1479 if (err < 0) {
1480 skb_free_datagram(sk, skb);
1481 return err;
1482 }
1483
1484 sock_recv_timestamp(msg, sk, skb);
1485
1486 if (msg->msg_name) {
1487 msg->msg_namelen = sizeof(struct sockaddr_can);
1488 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1489 }
1490
1491 skb_free_datagram(sk, skb);
1492
1493 return size;
1494}
1495
1496static struct proto_ops bcm_ops __read_mostly = {
1497 .family = PF_CAN,
1498 .release = bcm_release,
1499 .bind = sock_no_bind,
1500 .connect = bcm_connect,
1501 .socketpair = sock_no_socketpair,
1502 .accept = sock_no_accept,
1503 .getname = sock_no_getname,
1504 .poll = datagram_poll,
1505 .ioctl = NULL, /* use can_ioctl() from af_can.c */
1506 .listen = sock_no_listen,
1507 .shutdown = sock_no_shutdown,
1508 .setsockopt = sock_no_setsockopt,
1509 .getsockopt = sock_no_getsockopt,
1510 .sendmsg = bcm_sendmsg,
1511 .recvmsg = bcm_recvmsg,
1512 .mmap = sock_no_mmap,
1513 .sendpage = sock_no_sendpage,
1514};
1515
1516static struct proto bcm_proto __read_mostly = {
1517 .name = "CAN_BCM",
1518 .owner = THIS_MODULE,
1519 .obj_size = sizeof(struct bcm_sock),
1520 .init = bcm_init,
1521};
1522
1523static struct can_proto bcm_can_proto __read_mostly = {
1524 .type = SOCK_DGRAM,
1525 .protocol = CAN_BCM,
1526 .capability = -1,
1527 .ops = &bcm_ops,
1528 .prot = &bcm_proto,
1529};
1530
1531static int __init bcm_module_init(void)
1532{
1533 int err;
1534
1535 printk(banner);
1536
1537 err = can_proto_register(&bcm_can_proto);
1538 if (err < 0) {
1539 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1540 return err;
1541 }
1542
1543 /* create /proc/net/can-bcm directory */
1544 proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
1545
1546 if (proc_dir)
1547 proc_dir->owner = THIS_MODULE;
1548
1549 return 0;
1550}
1551
1552static void __exit bcm_module_exit(void)
1553{
1554 can_proto_unregister(&bcm_can_proto);
1555
1556 if (proc_dir)
1557 proc_net_remove(&init_net, "can-bcm");
1558}
1559
1560module_init(bcm_module_init);
1561module_exit(bcm_module_exit);
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