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/hrtimer.h>
47 #include <linux/list.h>
48 #include <linux/proc_fs.h>
49 #include <linux/uio.h>
50 #include <linux/net.h>
51 #include <linux/netdevice.h>
52 #include <linux/socket.h>
53 #include <linux/if_arp.h>
54 #include <linux/skbuff.h>
55 #include <linux/can.h>
56 #include <linux/can/core.h>
57 #include <linux/can/bcm.h>
58 #include <net/sock.h>
59 #include <net/net_namespace.h>
60
61 /* use of last_frames[index].can_dlc */
62 #define RX_RECV 0x40 /* received data for this element */
63 #define RX_THR 0x80 /* element not been sent due to throttle feature */
64 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
65
66 /* get best masking value for can_rx_register() for a given single can_id */
67 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
68 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
69 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
70
71 #define CAN_BCM_VERSION CAN_VERSION
72 static __initdata const char banner[] = KERN_INFO
73 "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
74
75 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
76 MODULE_LICENSE("Dual BSD/GPL");
77 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
78 MODULE_ALIAS("can-proto-2");
79
80 /* easy access to can_frame payload */
81 static inline u64 GET_U64(const struct can_frame *cp)
82 {
83 return *(u64 *)cp->data;
84 }
85
86 struct bcm_op {
87 struct list_head list;
88 int ifindex;
89 canid_t can_id;
90 int flags;
91 unsigned long frames_abs, frames_filtered;
92 struct timeval ival1, ival2;
93 struct hrtimer timer, thrtimer;
94 struct tasklet_struct tsklet, thrtsklet;
95 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
96 int rx_ifindex;
97 int count;
98 int nframes;
99 int currframe;
100 struct can_frame *frames;
101 struct can_frame *last_frames;
102 struct can_frame sframe;
103 struct can_frame last_sframe;
104 struct sock *sk;
105 struct net_device *rx_reg_dev;
106 };
107
108 static struct proc_dir_entry *proc_dir;
109
110 struct bcm_sock {
111 struct sock sk;
112 int bound;
113 int ifindex;
114 struct notifier_block notifier;
115 struct list_head rx_ops;
116 struct list_head tx_ops;
117 unsigned long dropped_usr_msgs;
118 struct proc_dir_entry *bcm_proc_read;
119 char procname [9]; /* pointer printed in ASCII with \0 */
120 };
121
122 static inline struct bcm_sock *bcm_sk(const struct sock *sk)
123 {
124 return (struct bcm_sock *)sk;
125 }
126
127 #define CFSIZ sizeof(struct can_frame)
128 #define OPSIZ sizeof(struct bcm_op)
129 #define MHSIZ sizeof(struct bcm_msg_head)
130
131 /*
132 * procfs functions
133 */
134 static char *bcm_proc_getifname(int ifindex)
135 {
136 struct net_device *dev;
137
138 if (!ifindex)
139 return "any";
140
141 /* no usage counting */
142 dev = __dev_get_by_index(&init_net, ifindex);
143 if (dev)
144 return dev->name;
145
146 return "???";
147 }
148
149 static int bcm_read_proc(char *page, char **start, off_t off,
150 int count, int *eof, void *data)
151 {
152 int len = 0;
153 struct sock *sk = (struct sock *)data;
154 struct bcm_sock *bo = bcm_sk(sk);
155 struct bcm_op *op;
156
157 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
158 sk->sk_socket);
159 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
160 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
161 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
162 bo->dropped_usr_msgs);
163 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
164 bcm_proc_getifname(bo->ifindex));
165 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n");
166
167 list_for_each_entry(op, &bo->rx_ops, list) {
168
169 unsigned long reduction;
170
171 /* print only active entries & prevent division by zero */
172 if (!op->frames_abs)
173 continue;
174
175 len += snprintf(page + len, PAGE_SIZE - len,
176 "rx_op: %03X %-5s ",
177 op->can_id, bcm_proc_getifname(op->ifindex));
178 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
179 op->nframes,
180 (op->flags & RX_CHECK_DLC)?'d':' ');
181 if (op->kt_ival1.tv64)
182 len += snprintf(page + len, PAGE_SIZE - len,
183 "timeo=%lld ",
184 (long long)
185 ktime_to_us(op->kt_ival1));
186
187 if (op->kt_ival2.tv64)
188 len += snprintf(page + len, PAGE_SIZE - len,
189 "thr=%lld ",
190 (long long)
191 ktime_to_us(op->kt_ival2));
192
193 len += snprintf(page + len, PAGE_SIZE - len,
194 "# recv %ld (%ld) => reduction: ",
195 op->frames_filtered, op->frames_abs);
196
197 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
198
199 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
200 (reduction == 100)?"near ":"", reduction);
201
202 if (len > PAGE_SIZE - 200) {
203 /* mark output cut off */
204 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
205 break;
206 }
207 }
208
209 list_for_each_entry(op, &bo->tx_ops, list) {
210
211 len += snprintf(page + len, PAGE_SIZE - len,
212 "tx_op: %03X %s [%d] ",
213 op->can_id, bcm_proc_getifname(op->ifindex),
214 op->nframes);
215
216 if (op->kt_ival1.tv64)
217 len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ",
218 (long long) ktime_to_us(op->kt_ival1));
219
220 if (op->kt_ival2.tv64)
221 len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ",
222 (long long) ktime_to_us(op->kt_ival2));
223
224 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
225 op->frames_abs);
226
227 if (len > PAGE_SIZE - 100) {
228 /* mark output cut off */
229 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
230 break;
231 }
232 }
233
234 len += snprintf(page + len, PAGE_SIZE - len, "\n");
235
236 *eof = 1;
237 return len;
238 }
239
240 /*
241 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
242 * of the given bcm tx op
243 */
244 static void bcm_can_tx(struct bcm_op *op)
245 {
246 struct sk_buff *skb;
247 struct net_device *dev;
248 struct can_frame *cf = &op->frames[op->currframe];
249
250 /* no target device? => exit */
251 if (!op->ifindex)
252 return;
253
254 dev = dev_get_by_index(&init_net, op->ifindex);
255 if (!dev) {
256 /* RFC: should this bcm_op remove itself here? */
257 return;
258 }
259
260 skb = alloc_skb(CFSIZ, gfp_any());
261 if (!skb)
262 goto out;
263
264 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
265
266 /* send with loopback */
267 skb->dev = dev;
268 skb->sk = op->sk;
269 can_send(skb, 1);
270
271 /* update statistics */
272 op->currframe++;
273 op->frames_abs++;
274
275 /* reached last frame? */
276 if (op->currframe >= op->nframes)
277 op->currframe = 0;
278 out:
279 dev_put(dev);
280 }
281
282 /*
283 * bcm_send_to_user - send a BCM message to the userspace
284 * (consisting of bcm_msg_head + x CAN frames)
285 */
286 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
287 struct can_frame *frames, int has_timestamp)
288 {
289 struct sk_buff *skb;
290 struct can_frame *firstframe;
291 struct sockaddr_can *addr;
292 struct sock *sk = op->sk;
293 int datalen = head->nframes * CFSIZ;
294 int err;
295
296 skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
297 if (!skb)
298 return;
299
300 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
301
302 if (head->nframes) {
303 /* can_frames starting here */
304 firstframe = (struct can_frame *)skb_tail_pointer(skb);
305
306 memcpy(skb_put(skb, datalen), frames, datalen);
307
308 /*
309 * the BCM uses the can_dlc-element of the can_frame
310 * structure for internal purposes. This is only
311 * relevant for updates that are generated by the
312 * BCM, where nframes is 1
313 */
314 if (head->nframes == 1)
315 firstframe->can_dlc &= BCM_CAN_DLC_MASK;
316 }
317
318 if (has_timestamp) {
319 /* restore rx timestamp */
320 skb->tstamp = op->rx_stamp;
321 }
322
323 /*
324 * Put the datagram to the queue so that bcm_recvmsg() can
325 * get it from there. We need to pass the interface index to
326 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
327 * containing the interface index.
328 */
329
330 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
331 addr = (struct sockaddr_can *)skb->cb;
332 memset(addr, 0, sizeof(*addr));
333 addr->can_family = AF_CAN;
334 addr->can_ifindex = op->rx_ifindex;
335
336 err = sock_queue_rcv_skb(sk, skb);
337 if (err < 0) {
338 struct bcm_sock *bo = bcm_sk(sk);
339
340 kfree_skb(skb);
341 /* don't care about overflows in this statistic */
342 bo->dropped_usr_msgs++;
343 }
344 }
345
346 static void bcm_tx_timeout_tsklet(unsigned long data)
347 {
348 struct bcm_op *op = (struct bcm_op *)data;
349 struct bcm_msg_head msg_head;
350
351 if (op->kt_ival1.tv64 && (op->count > 0)) {
352
353 op->count--;
354 if (!op->count && (op->flags & TX_COUNTEVT)) {
355
356 /* create notification to user */
357 msg_head.opcode = TX_EXPIRED;
358 msg_head.flags = op->flags;
359 msg_head.count = op->count;
360 msg_head.ival1 = op->ival1;
361 msg_head.ival2 = op->ival2;
362 msg_head.can_id = op->can_id;
363 msg_head.nframes = 0;
364
365 bcm_send_to_user(op, &msg_head, NULL, 0);
366 }
367 }
368
369 if (op->kt_ival1.tv64 && (op->count > 0)) {
370
371 /* send (next) frame */
372 bcm_can_tx(op);
373 hrtimer_start(&op->timer,
374 ktime_add(ktime_get(), op->kt_ival1),
375 HRTIMER_MODE_ABS);
376
377 } else {
378 if (op->kt_ival2.tv64) {
379
380 /* send (next) frame */
381 bcm_can_tx(op);
382 hrtimer_start(&op->timer,
383 ktime_add(ktime_get(), op->kt_ival2),
384 HRTIMER_MODE_ABS);
385 }
386 }
387 }
388
389 /*
390 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
391 */
392 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
393 {
394 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
395
396 tasklet_schedule(&op->tsklet);
397
398 return HRTIMER_NORESTART;
399 }
400
401 /*
402 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
403 */
404 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
405 {
406 struct bcm_msg_head head;
407
408 /* update statistics */
409 op->frames_filtered++;
410
411 /* prevent statistics overflow */
412 if (op->frames_filtered > ULONG_MAX/100)
413 op->frames_filtered = op->frames_abs = 0;
414
415 /* this element is not throttled anymore */
416 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
417
418 head.opcode = RX_CHANGED;
419 head.flags = op->flags;
420 head.count = op->count;
421 head.ival1 = op->ival1;
422 head.ival2 = op->ival2;
423 head.can_id = op->can_id;
424 head.nframes = 1;
425
426 bcm_send_to_user(op, &head, data, 1);
427 }
428
429 /*
430 * bcm_rx_update_and_send - process a detected relevant receive content change
431 * 1. update the last received data
432 * 2. send a notification to the user (if possible)
433 */
434 static void bcm_rx_update_and_send(struct bcm_op *op,
435 struct can_frame *lastdata,
436 const struct can_frame *rxdata)
437 {
438 memcpy(lastdata, rxdata, CFSIZ);
439
440 /* mark as used and throttled by default */
441 lastdata->can_dlc |= (RX_RECV|RX_THR);
442
443 /* throtteling mode inactive ? */
444 if (!op->kt_ival2.tv64) {
445 /* send RX_CHANGED to the user immediately */
446 bcm_rx_changed(op, lastdata);
447 return;
448 }
449
450 /* with active throttling timer we are just done here */
451 if (hrtimer_active(&op->thrtimer))
452 return;
453
454 /* first receiption with enabled throttling mode */
455 if (!op->kt_lastmsg.tv64)
456 goto rx_changed_settime;
457
458 /* got a second frame inside a potential throttle period? */
459 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
460 ktime_to_us(op->kt_ival2)) {
461 /* do not send the saved data - only start throttle timer */
462 hrtimer_start(&op->thrtimer,
463 ktime_add(op->kt_lastmsg, op->kt_ival2),
464 HRTIMER_MODE_ABS);
465 return;
466 }
467
468 /* the gap was that big, that throttling was not needed here */
469 rx_changed_settime:
470 bcm_rx_changed(op, lastdata);
471 op->kt_lastmsg = ktime_get();
472 }
473
474 /*
475 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
476 * received data stored in op->last_frames[]
477 */
478 static void bcm_rx_cmp_to_index(struct bcm_op *op, int index,
479 const struct can_frame *rxdata)
480 {
481 /*
482 * no one uses the MSBs of can_dlc for comparation,
483 * so we use it here to detect the first time of reception
484 */
485
486 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
487 /* received data for the first time => send update to user */
488 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
489 return;
490 }
491
492 /* do a real check in can_frame data section */
493
494 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
495 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
496 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
497 return;
498 }
499
500 if (op->flags & RX_CHECK_DLC) {
501 /* do a real check in can_frame dlc */
502 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
503 BCM_CAN_DLC_MASK)) {
504 bcm_rx_update_and_send(op, &op->last_frames[index],
505 rxdata);
506 return;
507 }
508 }
509 }
510
511 /*
512 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
513 */
514 static void bcm_rx_starttimer(struct bcm_op *op)
515 {
516 if (op->flags & RX_NO_AUTOTIMER)
517 return;
518
519 if (op->kt_ival1.tv64)
520 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
521 }
522
523 static void bcm_rx_timeout_tsklet(unsigned long data)
524 {
525 struct bcm_op *op = (struct bcm_op *)data;
526 struct bcm_msg_head msg_head;
527
528 /* create notification to user */
529 msg_head.opcode = RX_TIMEOUT;
530 msg_head.flags = op->flags;
531 msg_head.count = op->count;
532 msg_head.ival1 = op->ival1;
533 msg_head.ival2 = op->ival2;
534 msg_head.can_id = op->can_id;
535 msg_head.nframes = 0;
536
537 bcm_send_to_user(op, &msg_head, NULL, 0);
538 }
539
540 /*
541 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
542 */
543 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
544 {
545 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
546
547 /* schedule before NET_RX_SOFTIRQ */
548 tasklet_hi_schedule(&op->tsklet);
549
550 /* no restart of the timer is done here! */
551
552 /* if user wants to be informed, when cyclic CAN-Messages come back */
553 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
554 /* clear received can_frames to indicate 'nothing received' */
555 memset(op->last_frames, 0, op->nframes * CFSIZ);
556 }
557
558 return HRTIMER_NORESTART;
559 }
560
561 /*
562 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
563 */
564 static inline int bcm_rx_do_flush(struct bcm_op *op, int update, int index)
565 {
566 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
567 if (update)
568 bcm_rx_changed(op, &op->last_frames[index]);
569 return 1;
570 }
571 return 0;
572 }
573
574 /*
575 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
576 *
577 * update == 0 : just check if throttled data is available (any irq context)
578 * update == 1 : check and send throttled data to userspace (soft_irq context)
579 */
580 static int bcm_rx_thr_flush(struct bcm_op *op, int update)
581 {
582 int updated = 0;
583
584 if (op->nframes > 1) {
585 int i;
586
587 /* for MUX filter we start at index 1 */
588 for (i = 1; i < op->nframes; i++)
589 updated += bcm_rx_do_flush(op, update, i);
590
591 } else {
592 /* for RX_FILTER_ID and simple filter */
593 updated += bcm_rx_do_flush(op, update, 0);
594 }
595
596 return updated;
597 }
598
599 static void bcm_rx_thr_tsklet(unsigned long data)
600 {
601 struct bcm_op *op = (struct bcm_op *)data;
602
603 /* push the changed data to the userspace */
604 bcm_rx_thr_flush(op, 1);
605 }
606
607 /*
608 * bcm_rx_thr_handler - the time for blocked content updates is over now:
609 * Check for throttled data and send it to the userspace
610 */
611 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
612 {
613 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
614
615 tasklet_schedule(&op->thrtsklet);
616
617 if (bcm_rx_thr_flush(op, 0)) {
618 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
619 return HRTIMER_RESTART;
620 } else {
621 /* rearm throttle handling */
622 op->kt_lastmsg = ktime_set(0, 0);
623 return HRTIMER_NORESTART;
624 }
625 }
626
627 /*
628 * bcm_rx_handler - handle a CAN frame receiption
629 */
630 static void bcm_rx_handler(struct sk_buff *skb, void *data)
631 {
632 struct bcm_op *op = (struct bcm_op *)data;
633 const struct can_frame *rxframe = (struct can_frame *)skb->data;
634 int i;
635
636 /* disable timeout */
637 hrtimer_cancel(&op->timer);
638
639 if (op->can_id != rxframe->can_id)
640 return;
641
642 /* save rx timestamp */
643 op->rx_stamp = skb->tstamp;
644 /* save originator for recvfrom() */
645 op->rx_ifindex = skb->dev->ifindex;
646 /* update statistics */
647 op->frames_abs++;
648
649 if (op->flags & RX_RTR_FRAME) {
650 /* send reply for RTR-request (placed in op->frames[0]) */
651 bcm_can_tx(op);
652 return;
653 }
654
655 if (op->flags & RX_FILTER_ID) {
656 /* the easiest case */
657 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
658 goto rx_starttimer;
659 }
660
661 if (op->nframes == 1) {
662 /* simple compare with index 0 */
663 bcm_rx_cmp_to_index(op, 0, rxframe);
664 goto rx_starttimer;
665 }
666
667 if (op->nframes > 1) {
668 /*
669 * multiplex compare
670 *
671 * find the first multiplex mask that fits.
672 * Remark: The MUX-mask is stored in index 0
673 */
674
675 for (i = 1; i < op->nframes; i++) {
676 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
677 (GET_U64(&op->frames[0]) &
678 GET_U64(&op->frames[i]))) {
679 bcm_rx_cmp_to_index(op, i, rxframe);
680 break;
681 }
682 }
683 }
684
685 rx_starttimer:
686 bcm_rx_starttimer(op);
687 }
688
689 /*
690 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
691 */
692 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
693 int ifindex)
694 {
695 struct bcm_op *op;
696
697 list_for_each_entry(op, ops, list) {
698 if ((op->can_id == can_id) && (op->ifindex == ifindex))
699 return op;
700 }
701
702 return NULL;
703 }
704
705 static void bcm_remove_op(struct bcm_op *op)
706 {
707 hrtimer_cancel(&op->timer);
708 hrtimer_cancel(&op->thrtimer);
709
710 if (op->tsklet.func)
711 tasklet_kill(&op->tsklet);
712
713 if (op->thrtsklet.func)
714 tasklet_kill(&op->thrtsklet);
715
716 if ((op->frames) && (op->frames != &op->sframe))
717 kfree(op->frames);
718
719 if ((op->last_frames) && (op->last_frames != &op->last_sframe))
720 kfree(op->last_frames);
721
722 kfree(op);
723
724 return;
725 }
726
727 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
728 {
729 if (op->rx_reg_dev == dev) {
730 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
731 bcm_rx_handler, op);
732
733 /* mark as removed subscription */
734 op->rx_reg_dev = NULL;
735 } else
736 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
737 "mismatch %p %p\n", op->rx_reg_dev, dev);
738 }
739
740 /*
741 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
742 */
743 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
744 {
745 struct bcm_op *op, *n;
746
747 list_for_each_entry_safe(op, n, ops, list) {
748 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
749
750 /*
751 * Don't care if we're bound or not (due to netdev
752 * problems) can_rx_unregister() is always a save
753 * thing to do here.
754 */
755 if (op->ifindex) {
756 /*
757 * Only remove subscriptions that had not
758 * been removed due to NETDEV_UNREGISTER
759 * in bcm_notifier()
760 */
761 if (op->rx_reg_dev) {
762 struct net_device *dev;
763
764 dev = dev_get_by_index(&init_net,
765 op->ifindex);
766 if (dev) {
767 bcm_rx_unreg(dev, op);
768 dev_put(dev);
769 }
770 }
771 } else
772 can_rx_unregister(NULL, op->can_id,
773 REGMASK(op->can_id),
774 bcm_rx_handler, op);
775
776 list_del(&op->list);
777 bcm_remove_op(op);
778 return 1; /* done */
779 }
780 }
781
782 return 0; /* not found */
783 }
784
785 /*
786 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
787 */
788 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
789 {
790 struct bcm_op *op, *n;
791
792 list_for_each_entry_safe(op, n, ops, list) {
793 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
794 list_del(&op->list);
795 bcm_remove_op(op);
796 return 1; /* done */
797 }
798 }
799
800 return 0; /* not found */
801 }
802
803 /*
804 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
805 */
806 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
807 int ifindex)
808 {
809 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
810
811 if (!op)
812 return -EINVAL;
813
814 /* put current values into msg_head */
815 msg_head->flags = op->flags;
816 msg_head->count = op->count;
817 msg_head->ival1 = op->ival1;
818 msg_head->ival2 = op->ival2;
819 msg_head->nframes = op->nframes;
820
821 bcm_send_to_user(op, msg_head, op->frames, 0);
822
823 return MHSIZ;
824 }
825
826 /*
827 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
828 */
829 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
830 int ifindex, struct sock *sk)
831 {
832 struct bcm_sock *bo = bcm_sk(sk);
833 struct bcm_op *op;
834 int i, err;
835
836 /* we need a real device to send frames */
837 if (!ifindex)
838 return -ENODEV;
839
840 /* we need at least one can_frame */
841 if (msg_head->nframes < 1)
842 return -EINVAL;
843
844 /* check the given can_id */
845 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
846
847 if (op) {
848 /* update existing BCM operation */
849
850 /*
851 * Do we need more space for the can_frames than currently
852 * allocated? -> This is a _really_ unusual use-case and
853 * therefore (complexity / locking) it is not supported.
854 */
855 if (msg_head->nframes > op->nframes)
856 return -E2BIG;
857
858 /* update can_frames content */
859 for (i = 0; i < msg_head->nframes; i++) {
860 err = memcpy_fromiovec((u8 *)&op->frames[i],
861 msg->msg_iov, CFSIZ);
862
863 if (op->frames[i].can_dlc > 8)
864 err = -EINVAL;
865
866 if (err < 0)
867 return err;
868
869 if (msg_head->flags & TX_CP_CAN_ID) {
870 /* copy can_id into frame */
871 op->frames[i].can_id = msg_head->can_id;
872 }
873 }
874
875 } else {
876 /* insert new BCM operation for the given can_id */
877
878 op = kzalloc(OPSIZ, GFP_KERNEL);
879 if (!op)
880 return -ENOMEM;
881
882 op->can_id = msg_head->can_id;
883
884 /* create array for can_frames and copy the data */
885 if (msg_head->nframes > 1) {
886 op->frames = kmalloc(msg_head->nframes * CFSIZ,
887 GFP_KERNEL);
888 if (!op->frames) {
889 kfree(op);
890 return -ENOMEM;
891 }
892 } else
893 op->frames = &op->sframe;
894
895 for (i = 0; i < msg_head->nframes; i++) {
896 err = memcpy_fromiovec((u8 *)&op->frames[i],
897 msg->msg_iov, CFSIZ);
898
899 if (op->frames[i].can_dlc > 8)
900 err = -EINVAL;
901
902 if (err < 0) {
903 if (op->frames != &op->sframe)
904 kfree(op->frames);
905 kfree(op);
906 return err;
907 }
908
909 if (msg_head->flags & TX_CP_CAN_ID) {
910 /* copy can_id into frame */
911 op->frames[i].can_id = msg_head->can_id;
912 }
913 }
914
915 /* tx_ops never compare with previous received messages */
916 op->last_frames = NULL;
917
918 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
919 op->sk = sk;
920 op->ifindex = ifindex;
921
922 /* initialize uninitialized (kzalloc) structure */
923 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
924 op->timer.function = bcm_tx_timeout_handler;
925
926 /* initialize tasklet for tx countevent notification */
927 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
928 (unsigned long) op);
929
930 /* currently unused in tx_ops */
931 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
932
933 /* add this bcm_op to the list of the tx_ops */
934 list_add(&op->list, &bo->tx_ops);
935
936 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
937
938 if (op->nframes != msg_head->nframes) {
939 op->nframes = msg_head->nframes;
940 /* start multiple frame transmission with index 0 */
941 op->currframe = 0;
942 }
943
944 /* check flags */
945
946 op->flags = msg_head->flags;
947
948 if (op->flags & TX_RESET_MULTI_IDX) {
949 /* start multiple frame transmission with index 0 */
950 op->currframe = 0;
951 }
952
953 if (op->flags & SETTIMER) {
954 /* set timer values */
955 op->count = msg_head->count;
956 op->ival1 = msg_head->ival1;
957 op->ival2 = msg_head->ival2;
958 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
959 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
960
961 /* disable an active timer due to zero values? */
962 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
963 hrtimer_cancel(&op->timer);
964 }
965
966 if ((op->flags & STARTTIMER) &&
967 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) {
968
969 /* spec: send can_frame when starting timer */
970 op->flags |= TX_ANNOUNCE;
971
972 if (op->kt_ival1.tv64 && (op->count > 0)) {
973 /* op->count-- is done in bcm_tx_timeout_handler */
974 hrtimer_start(&op->timer, op->kt_ival1,
975 HRTIMER_MODE_REL);
976 } else
977 hrtimer_start(&op->timer, op->kt_ival2,
978 HRTIMER_MODE_REL);
979 }
980
981 if (op->flags & TX_ANNOUNCE)
982 bcm_can_tx(op);
983
984 return msg_head->nframes * CFSIZ + MHSIZ;
985 }
986
987 /*
988 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
989 */
990 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
991 int ifindex, struct sock *sk)
992 {
993 struct bcm_sock *bo = bcm_sk(sk);
994 struct bcm_op *op;
995 int do_rx_register;
996 int err = 0;
997
998 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
999 /* be robust against wrong usage ... */
1000 msg_head->flags |= RX_FILTER_ID;
1001 /* ignore trailing garbage */
1002 msg_head->nframes = 0;
1003 }
1004
1005 if ((msg_head->flags & RX_RTR_FRAME) &&
1006 ((msg_head->nframes != 1) ||
1007 (!(msg_head->can_id & CAN_RTR_FLAG))))
1008 return -EINVAL;
1009
1010 /* check the given can_id */
1011 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
1012 if (op) {
1013 /* update existing BCM operation */
1014
1015 /*
1016 * Do we need more space for the can_frames than currently
1017 * allocated? -> This is a _really_ unusual use-case and
1018 * therefore (complexity / locking) it is not supported.
1019 */
1020 if (msg_head->nframes > op->nframes)
1021 return -E2BIG;
1022
1023 if (msg_head->nframes) {
1024 /* update can_frames content */
1025 err = memcpy_fromiovec((u8 *)op->frames,
1026 msg->msg_iov,
1027 msg_head->nframes * CFSIZ);
1028 if (err < 0)
1029 return err;
1030
1031 /* clear last_frames to indicate 'nothing received' */
1032 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
1033 }
1034
1035 op->nframes = msg_head->nframes;
1036
1037 /* Only an update -> do not call can_rx_register() */
1038 do_rx_register = 0;
1039
1040 } else {
1041 /* insert new BCM operation for the given can_id */
1042 op = kzalloc(OPSIZ, GFP_KERNEL);
1043 if (!op)
1044 return -ENOMEM;
1045
1046 op->can_id = msg_head->can_id;
1047 op->nframes = msg_head->nframes;
1048
1049 if (msg_head->nframes > 1) {
1050 /* create array for can_frames and copy the data */
1051 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1052 GFP_KERNEL);
1053 if (!op->frames) {
1054 kfree(op);
1055 return -ENOMEM;
1056 }
1057
1058 /* create and init array for received can_frames */
1059 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1060 GFP_KERNEL);
1061 if (!op->last_frames) {
1062 kfree(op->frames);
1063 kfree(op);
1064 return -ENOMEM;
1065 }
1066
1067 } else {
1068 op->frames = &op->sframe;
1069 op->last_frames = &op->last_sframe;
1070 }
1071
1072 if (msg_head->nframes) {
1073 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1074 msg_head->nframes * CFSIZ);
1075 if (err < 0) {
1076 if (op->frames != &op->sframe)
1077 kfree(op->frames);
1078 if (op->last_frames != &op->last_sframe)
1079 kfree(op->last_frames);
1080 kfree(op);
1081 return err;
1082 }
1083 }
1084
1085 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1086 op->sk = sk;
1087 op->ifindex = ifindex;
1088
1089 /* initialize uninitialized (kzalloc) structure */
1090 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1091 op->timer.function = bcm_rx_timeout_handler;
1092
1093 /* initialize tasklet for rx timeout notification */
1094 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
1095 (unsigned long) op);
1096
1097 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1098 op->thrtimer.function = bcm_rx_thr_handler;
1099
1100 /* initialize tasklet for rx throttle handling */
1101 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
1102 (unsigned long) op);
1103
1104 /* add this bcm_op to the list of the rx_ops */
1105 list_add(&op->list, &bo->rx_ops);
1106
1107 /* call can_rx_register() */
1108 do_rx_register = 1;
1109
1110 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1111
1112 /* check flags */
1113 op->flags = msg_head->flags;
1114
1115 if (op->flags & RX_RTR_FRAME) {
1116
1117 /* no timers in RTR-mode */
1118 hrtimer_cancel(&op->thrtimer);
1119 hrtimer_cancel(&op->timer);
1120
1121 /*
1122 * funny feature in RX(!)_SETUP only for RTR-mode:
1123 * copy can_id into frame BUT without RTR-flag to
1124 * prevent a full-load-loopback-test ... ;-]
1125 */
1126 if ((op->flags & TX_CP_CAN_ID) ||
1127 (op->frames[0].can_id == op->can_id))
1128 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1129
1130 } else {
1131 if (op->flags & SETTIMER) {
1132
1133 /* set timer value */
1134 op->ival1 = msg_head->ival1;
1135 op->ival2 = msg_head->ival2;
1136 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1137 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1138
1139 /* disable an active timer due to zero value? */
1140 if (!op->kt_ival1.tv64)
1141 hrtimer_cancel(&op->timer);
1142
1143 /*
1144 * In any case cancel the throttle timer, flush
1145 * potentially blocked msgs and reset throttle handling
1146 */
1147 op->kt_lastmsg = ktime_set(0, 0);
1148 hrtimer_cancel(&op->thrtimer);
1149 bcm_rx_thr_flush(op, 1);
1150 }
1151
1152 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
1153 hrtimer_start(&op->timer, op->kt_ival1,
1154 HRTIMER_MODE_REL);
1155 }
1156
1157 /* now we can register for can_ids, if we added a new bcm_op */
1158 if (do_rx_register) {
1159 if (ifindex) {
1160 struct net_device *dev;
1161
1162 dev = dev_get_by_index(&init_net, ifindex);
1163 if (dev) {
1164 err = can_rx_register(dev, op->can_id,
1165 REGMASK(op->can_id),
1166 bcm_rx_handler, op,
1167 "bcm");
1168
1169 op->rx_reg_dev = dev;
1170 dev_put(dev);
1171 }
1172
1173 } else
1174 err = can_rx_register(NULL, op->can_id,
1175 REGMASK(op->can_id),
1176 bcm_rx_handler, op, "bcm");
1177 if (err) {
1178 /* this bcm rx op is broken -> remove it */
1179 list_del(&op->list);
1180 bcm_remove_op(op);
1181 return err;
1182 }
1183 }
1184
1185 return msg_head->nframes * CFSIZ + MHSIZ;
1186 }
1187
1188 /*
1189 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1190 */
1191 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1192 {
1193 struct sk_buff *skb;
1194 struct net_device *dev;
1195 int err;
1196
1197 /* we need a real device to send frames */
1198 if (!ifindex)
1199 return -ENODEV;
1200
1201 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1202
1203 if (!skb)
1204 return -ENOMEM;
1205
1206 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1207 if (err < 0) {
1208 kfree_skb(skb);
1209 return err;
1210 }
1211
1212 dev = dev_get_by_index(&init_net, ifindex);
1213 if (!dev) {
1214 kfree_skb(skb);
1215 return -ENODEV;
1216 }
1217
1218 skb->dev = dev;
1219 skb->sk = sk;
1220 err = can_send(skb, 1); /* send with loopback */
1221 dev_put(dev);
1222
1223 if (err)
1224 return err;
1225
1226 return CFSIZ + MHSIZ;
1227 }
1228
1229 /*
1230 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1231 */
1232 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1233 struct msghdr *msg, size_t size)
1234 {
1235 struct sock *sk = sock->sk;
1236 struct bcm_sock *bo = bcm_sk(sk);
1237 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1238 struct bcm_msg_head msg_head;
1239 int ret; /* read bytes or error codes as return value */
1240
1241 if (!bo->bound)
1242 return -ENOTCONN;
1243
1244 /* check for valid message length from userspace */
1245 if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
1246 return -EINVAL;
1247
1248 /* check for alternative ifindex for this bcm_op */
1249
1250 if (!ifindex && msg->msg_name) {
1251 /* no bound device as default => check msg_name */
1252 struct sockaddr_can *addr =
1253 (struct sockaddr_can *)msg->msg_name;
1254
1255 if (addr->can_family != AF_CAN)
1256 return -EINVAL;
1257
1258 /* ifindex from sendto() */
1259 ifindex = addr->can_ifindex;
1260
1261 if (ifindex) {
1262 struct net_device *dev;
1263
1264 dev = dev_get_by_index(&init_net, ifindex);
1265 if (!dev)
1266 return -ENODEV;
1267
1268 if (dev->type != ARPHRD_CAN) {
1269 dev_put(dev);
1270 return -ENODEV;
1271 }
1272
1273 dev_put(dev);
1274 }
1275 }
1276
1277 /* read message head information */
1278
1279 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1280 if (ret < 0)
1281 return ret;
1282
1283 lock_sock(sk);
1284
1285 switch (msg_head.opcode) {
1286
1287 case TX_SETUP:
1288 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1289 break;
1290
1291 case RX_SETUP:
1292 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1293 break;
1294
1295 case TX_DELETE:
1296 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1297 ret = MHSIZ;
1298 else
1299 ret = -EINVAL;
1300 break;
1301
1302 case RX_DELETE:
1303 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1304 ret = MHSIZ;
1305 else
1306 ret = -EINVAL;
1307 break;
1308
1309 case TX_READ:
1310 /* reuse msg_head for the reply to TX_READ */
1311 msg_head.opcode = TX_STATUS;
1312 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1313 break;
1314
1315 case RX_READ:
1316 /* reuse msg_head for the reply to RX_READ */
1317 msg_head.opcode = RX_STATUS;
1318 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1319 break;
1320
1321 case TX_SEND:
1322 /* we need exactly one can_frame behind the msg head */
1323 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
1324 ret = -EINVAL;
1325 else
1326 ret = bcm_tx_send(msg, ifindex, sk);
1327 break;
1328
1329 default:
1330 ret = -EINVAL;
1331 break;
1332 }
1333
1334 release_sock(sk);
1335
1336 return ret;
1337 }
1338
1339 /*
1340 * notification handler for netdevice status changes
1341 */
1342 static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1343 void *data)
1344 {
1345 struct net_device *dev = (struct net_device *)data;
1346 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1347 struct sock *sk = &bo->sk;
1348 struct bcm_op *op;
1349 int notify_enodev = 0;
1350
1351 if (!net_eq(dev_net(dev), &init_net))
1352 return NOTIFY_DONE;
1353
1354 if (dev->type != ARPHRD_CAN)
1355 return NOTIFY_DONE;
1356
1357 switch (msg) {
1358
1359 case NETDEV_UNREGISTER:
1360 lock_sock(sk);
1361
1362 /* remove device specific receive entries */
1363 list_for_each_entry(op, &bo->rx_ops, list)
1364 if (op->rx_reg_dev == dev)
1365 bcm_rx_unreg(dev, op);
1366
1367 /* remove device reference, if this is our bound device */
1368 if (bo->bound && bo->ifindex == dev->ifindex) {
1369 bo->bound = 0;
1370 bo->ifindex = 0;
1371 notify_enodev = 1;
1372 }
1373
1374 release_sock(sk);
1375
1376 if (notify_enodev) {
1377 sk->sk_err = ENODEV;
1378 if (!sock_flag(sk, SOCK_DEAD))
1379 sk->sk_error_report(sk);
1380 }
1381 break;
1382
1383 case NETDEV_DOWN:
1384 if (bo->bound && bo->ifindex == dev->ifindex) {
1385 sk->sk_err = ENETDOWN;
1386 if (!sock_flag(sk, SOCK_DEAD))
1387 sk->sk_error_report(sk);
1388 }
1389 }
1390
1391 return NOTIFY_DONE;
1392 }
1393
1394 /*
1395 * initial settings for all BCM sockets to be set at socket creation time
1396 */
1397 static int bcm_init(struct sock *sk)
1398 {
1399 struct bcm_sock *bo = bcm_sk(sk);
1400
1401 bo->bound = 0;
1402 bo->ifindex = 0;
1403 bo->dropped_usr_msgs = 0;
1404 bo->bcm_proc_read = NULL;
1405
1406 INIT_LIST_HEAD(&bo->tx_ops);
1407 INIT_LIST_HEAD(&bo->rx_ops);
1408
1409 /* set notifier */
1410 bo->notifier.notifier_call = bcm_notifier;
1411
1412 register_netdevice_notifier(&bo->notifier);
1413
1414 return 0;
1415 }
1416
1417 /*
1418 * standard socket functions
1419 */
1420 static int bcm_release(struct socket *sock)
1421 {
1422 struct sock *sk = sock->sk;
1423 struct bcm_sock *bo = bcm_sk(sk);
1424 struct bcm_op *op, *next;
1425
1426 /* remove bcm_ops, timer, rx_unregister(), etc. */
1427
1428 unregister_netdevice_notifier(&bo->notifier);
1429
1430 lock_sock(sk);
1431
1432 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1433 bcm_remove_op(op);
1434
1435 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1436 /*
1437 * Don't care if we're bound or not (due to netdev problems)
1438 * can_rx_unregister() is always a save thing to do here.
1439 */
1440 if (op->ifindex) {
1441 /*
1442 * Only remove subscriptions that had not
1443 * been removed due to NETDEV_UNREGISTER
1444 * in bcm_notifier()
1445 */
1446 if (op->rx_reg_dev) {
1447 struct net_device *dev;
1448
1449 dev = dev_get_by_index(&init_net, op->ifindex);
1450 if (dev) {
1451 bcm_rx_unreg(dev, op);
1452 dev_put(dev);
1453 }
1454 }
1455 } else
1456 can_rx_unregister(NULL, op->can_id,
1457 REGMASK(op->can_id),
1458 bcm_rx_handler, op);
1459
1460 bcm_remove_op(op);
1461 }
1462
1463 /* remove procfs entry */
1464 if (proc_dir && bo->bcm_proc_read)
1465 remove_proc_entry(bo->procname, proc_dir);
1466
1467 /* remove device reference */
1468 if (bo->bound) {
1469 bo->bound = 0;
1470 bo->ifindex = 0;
1471 }
1472
1473 sock_orphan(sk);
1474 sock->sk = NULL;
1475
1476 release_sock(sk);
1477 sock_put(sk);
1478
1479 return 0;
1480 }
1481
1482 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1483 int flags)
1484 {
1485 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1486 struct sock *sk = sock->sk;
1487 struct bcm_sock *bo = bcm_sk(sk);
1488
1489 if (bo->bound)
1490 return -EISCONN;
1491
1492 /* bind a device to this socket */
1493 if (addr->can_ifindex) {
1494 struct net_device *dev;
1495
1496 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1497 if (!dev)
1498 return -ENODEV;
1499
1500 if (dev->type != ARPHRD_CAN) {
1501 dev_put(dev);
1502 return -ENODEV;
1503 }
1504
1505 bo->ifindex = dev->ifindex;
1506 dev_put(dev);
1507
1508 } else {
1509 /* no interface reference for ifindex = 0 ('any' CAN device) */
1510 bo->ifindex = 0;
1511 }
1512
1513 bo->bound = 1;
1514
1515 if (proc_dir) {
1516 /* unique socket address as filename */
1517 sprintf(bo->procname, "%p", sock);
1518 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
1519 proc_dir,
1520 bcm_read_proc, sk);
1521 }
1522
1523 return 0;
1524 }
1525
1526 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1527 struct msghdr *msg, size_t size, int flags)
1528 {
1529 struct sock *sk = sock->sk;
1530 struct sk_buff *skb;
1531 int error = 0;
1532 int noblock;
1533 int err;
1534
1535 noblock = flags & MSG_DONTWAIT;
1536 flags &= ~MSG_DONTWAIT;
1537 skb = skb_recv_datagram(sk, flags, noblock, &error);
1538 if (!skb)
1539 return error;
1540
1541 if (skb->len < size)
1542 size = skb->len;
1543
1544 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1545 if (err < 0) {
1546 skb_free_datagram(sk, skb);
1547 return err;
1548 }
1549
1550 sock_recv_timestamp(msg, sk, skb);
1551
1552 if (msg->msg_name) {
1553 msg->msg_namelen = sizeof(struct sockaddr_can);
1554 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1555 }
1556
1557 skb_free_datagram(sk, skb);
1558
1559 return size;
1560 }
1561
1562 static struct proto_ops bcm_ops __read_mostly = {
1563 .family = PF_CAN,
1564 .release = bcm_release,
1565 .bind = sock_no_bind,
1566 .connect = bcm_connect,
1567 .socketpair = sock_no_socketpair,
1568 .accept = sock_no_accept,
1569 .getname = sock_no_getname,
1570 .poll = datagram_poll,
1571 .ioctl = NULL, /* use can_ioctl() from af_can.c */
1572 .listen = sock_no_listen,
1573 .shutdown = sock_no_shutdown,
1574 .setsockopt = sock_no_setsockopt,
1575 .getsockopt = sock_no_getsockopt,
1576 .sendmsg = bcm_sendmsg,
1577 .recvmsg = bcm_recvmsg,
1578 .mmap = sock_no_mmap,
1579 .sendpage = sock_no_sendpage,
1580 };
1581
1582 static struct proto bcm_proto __read_mostly = {
1583 .name = "CAN_BCM",
1584 .owner = THIS_MODULE,
1585 .obj_size = sizeof(struct bcm_sock),
1586 .init = bcm_init,
1587 };
1588
1589 static struct can_proto bcm_can_proto __read_mostly = {
1590 .type = SOCK_DGRAM,
1591 .protocol = CAN_BCM,
1592 .capability = -1,
1593 .ops = &bcm_ops,
1594 .prot = &bcm_proto,
1595 };
1596
1597 static int __init bcm_module_init(void)
1598 {
1599 int err;
1600
1601 printk(banner);
1602
1603 err = can_proto_register(&bcm_can_proto);
1604 if (err < 0) {
1605 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1606 return err;
1607 }
1608
1609 /* create /proc/net/can-bcm directory */
1610 proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
1611 return 0;
1612 }
1613
1614 static void __exit bcm_module_exit(void)
1615 {
1616 can_proto_unregister(&bcm_can_proto);
1617
1618 if (proc_dir)
1619 proc_net_remove(&init_net, "can-bcm");
1620 }
1621
1622 module_init(bcm_module_init);
1623 module_exit(bcm_module_exit);
1624
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