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/seq_file.h>
50 #include <linux/uio.h>
51 #include <linux/net.h>
52 #include <linux/netdevice.h>
53 #include <linux/socket.h>
54 #include <linux/if_arp.h>
55 #include <linux/skbuff.h>
56 #include <linux/can.h>
57 #include <linux/can/core.h>
58 #include <linux/can/bcm.h>
59 #include <net/sock.h>
60 #include <net/net_namespace.h>
61
62 /*
63 * To send multiple CAN frame content within TX_SETUP or to filter
64 * CAN messages with multiplex index within RX_SETUP, the number of
65 * different filters is limited to 256 due to the one byte index value.
66 */
67 #define MAX_NFRAMES 256
68
69 /* use of last_frames[index].can_dlc */
70 #define RX_RECV 0x40 /* received data for this element */
71 #define RX_THR 0x80 /* element not been sent due to throttle feature */
72 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
73
74 /* get best masking value for can_rx_register() for a given single can_id */
75 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
76 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
77 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
78
79 #define CAN_BCM_VERSION CAN_VERSION
80 static __initdata const char banner[] = KERN_INFO
81 "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
82
83 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
84 MODULE_LICENSE("Dual BSD/GPL");
85 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
86 MODULE_ALIAS("can-proto-2");
87
88 /* easy access to can_frame payload */
89 static inline u64 GET_U64(const struct can_frame *cp)
90 {
91 return *(u64 *)cp->data;
92 }
93
94 struct bcm_op {
95 struct list_head list;
96 int ifindex;
97 canid_t can_id;
98 u32 flags;
99 unsigned long frames_abs, frames_filtered;
100 struct timeval ival1, ival2;
101 struct hrtimer timer, thrtimer;
102 struct tasklet_struct tsklet, thrtsklet;
103 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
104 int rx_ifindex;
105 u32 count;
106 u32 nframes;
107 u32 currframe;
108 struct can_frame *frames;
109 struct can_frame *last_frames;
110 struct can_frame sframe;
111 struct can_frame last_sframe;
112 struct sock *sk;
113 struct net_device *rx_reg_dev;
114 };
115
116 static struct proc_dir_entry *proc_dir;
117
118 struct bcm_sock {
119 struct sock sk;
120 int bound;
121 int ifindex;
122 struct notifier_block notifier;
123 struct list_head rx_ops;
124 struct list_head tx_ops;
125 unsigned long dropped_usr_msgs;
126 struct proc_dir_entry *bcm_proc_read;
127 char procname [32]; /* inode number in decimal with \0 */
128 };
129
130 static inline struct bcm_sock *bcm_sk(const struct sock *sk)
131 {
132 return (struct bcm_sock *)sk;
133 }
134
135 #define CFSIZ sizeof(struct can_frame)
136 #define OPSIZ sizeof(struct bcm_op)
137 #define MHSIZ sizeof(struct bcm_msg_head)
138
139 /*
140 * procfs functions
141 */
142 static char *bcm_proc_getifname(char *result, int ifindex)
143 {
144 struct net_device *dev;
145
146 if (!ifindex)
147 return "any";
148
149 read_lock(&dev_base_lock);
150 dev = __dev_get_by_index(&init_net, ifindex);
151 if (dev)
152 strcpy(result, dev->name);
153 else
154 strcpy(result, "???");
155 read_unlock(&dev_base_lock);
156
157 return result;
158 }
159
160 static int bcm_proc_show(struct seq_file *m, void *v)
161 {
162 char ifname[IFNAMSIZ];
163 struct sock *sk = (struct sock *)m->private;
164 struct bcm_sock *bo = bcm_sk(sk);
165 struct bcm_op *op;
166
167 seq_printf(m, ">>> socket %p", sk->sk_socket);
168 seq_printf(m, " / sk %p", sk);
169 seq_printf(m, " / bo %p", bo);
170 seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs);
171 seq_printf(m, " / bound %s", bcm_proc_getifname(ifname, bo->ifindex));
172 seq_printf(m, " <<<\n");
173
174 list_for_each_entry(op, &bo->rx_ops, list) {
175
176 unsigned long reduction;
177
178 /* print only active entries & prevent division by zero */
179 if (!op->frames_abs)
180 continue;
181
182 seq_printf(m, "rx_op: %03X %-5s ",
183 op->can_id, bcm_proc_getifname(ifname, op->ifindex));
184 seq_printf(m, "[%u]%c ", op->nframes,
185 (op->flags & RX_CHECK_DLC)?'d':' ');
186 if (op->kt_ival1.tv64)
187 seq_printf(m, "timeo=%lld ",
188 (long long)
189 ktime_to_us(op->kt_ival1));
190
191 if (op->kt_ival2.tv64)
192 seq_printf(m, "thr=%lld ",
193 (long long)
194 ktime_to_us(op->kt_ival2));
195
196 seq_printf(m, "# recv %ld (%ld) => reduction: ",
197 op->frames_filtered, op->frames_abs);
198
199 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
200
201 seq_printf(m, "%s%ld%%\n",
202 (reduction == 100)?"near ":"", reduction);
203 }
204
205 list_for_each_entry(op, &bo->tx_ops, list) {
206
207 seq_printf(m, "tx_op: %03X %s [%u] ",
208 op->can_id,
209 bcm_proc_getifname(ifname, op->ifindex),
210 op->nframes);
211
212 if (op->kt_ival1.tv64)
213 seq_printf(m, "t1=%lld ",
214 (long long) ktime_to_us(op->kt_ival1));
215
216 if (op->kt_ival2.tv64)
217 seq_printf(m, "t2=%lld ",
218 (long long) ktime_to_us(op->kt_ival2));
219
220 seq_printf(m, "# sent %ld\n", op->frames_abs);
221 }
222 seq_putc(m, '\n');
223 return 0;
224 }
225
226 static int bcm_proc_open(struct inode *inode, struct file *file)
227 {
228 return single_open(file, bcm_proc_show, PDE(inode)->data);
229 }
230
231 static const struct file_operations bcm_proc_fops = {
232 .owner = THIS_MODULE,
233 .open = bcm_proc_open,
234 .read = seq_read,
235 .llseek = seq_lseek,
236 .release = single_release,
237 };
238
239 /*
240 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
241 * of the given bcm tx op
242 */
243 static void bcm_can_tx(struct bcm_op *op)
244 {
245 struct sk_buff *skb;
246 struct net_device *dev;
247 struct can_frame *cf = &op->frames[op->currframe];
248
249 /* no target device? => exit */
250 if (!op->ifindex)
251 return;
252
253 dev = dev_get_by_index(&init_net, op->ifindex);
254 if (!dev) {
255 /* RFC: should this bcm_op remove itself here? */
256 return;
257 }
258
259 skb = alloc_skb(CFSIZ, gfp_any());
260 if (!skb)
261 goto out;
262
263 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
264
265 /* send with loopback */
266 skb->dev = dev;
267 skb->sk = op->sk;
268 can_send(skb, 1);
269
270 /* update statistics */
271 op->currframe++;
272 op->frames_abs++;
273
274 /* reached last frame? */
275 if (op->currframe >= op->nframes)
276 op->currframe = 0;
277 out:
278 dev_put(dev);
279 }
280
281 /*
282 * bcm_send_to_user - send a BCM message to the userspace
283 * (consisting of bcm_msg_head + x CAN frames)
284 */
285 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
286 struct can_frame *frames, int has_timestamp)
287 {
288 struct sk_buff *skb;
289 struct can_frame *firstframe;
290 struct sockaddr_can *addr;
291 struct sock *sk = op->sk;
292 unsigned int datalen = head->nframes * CFSIZ;
293 int err;
294
295 skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
296 if (!skb)
297 return;
298
299 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
300
301 if (head->nframes) {
302 /* can_frames starting here */
303 firstframe = (struct can_frame *)skb_tail_pointer(skb);
304
305 memcpy(skb_put(skb, datalen), frames, datalen);
306
307 /*
308 * the BCM uses the can_dlc-element of the can_frame
309 * structure for internal purposes. This is only
310 * relevant for updates that are generated by the
311 * BCM, where nframes is 1
312 */
313 if (head->nframes == 1)
314 firstframe->can_dlc &= BCM_CAN_DLC_MASK;
315 }
316
317 if (has_timestamp) {
318 /* restore rx timestamp */
319 skb->tstamp = op->rx_stamp;
320 }
321
322 /*
323 * Put the datagram to the queue so that bcm_recvmsg() can
324 * get it from there. We need to pass the interface index to
325 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
326 * containing the interface index.
327 */
328
329 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
330 addr = (struct sockaddr_can *)skb->cb;
331 memset(addr, 0, sizeof(*addr));
332 addr->can_family = AF_CAN;
333 addr->can_ifindex = op->rx_ifindex;
334
335 err = sock_queue_rcv_skb(sk, skb);
336 if (err < 0) {
337 struct bcm_sock *bo = bcm_sk(sk);
338
339 kfree_skb(skb);
340 /* don't care about overflows in this statistic */
341 bo->dropped_usr_msgs++;
342 }
343 }
344
345 static void bcm_tx_timeout_tsklet(unsigned long data)
346 {
347 struct bcm_op *op = (struct bcm_op *)data;
348 struct bcm_msg_head msg_head;
349
350 if (op->kt_ival1.tv64 && (op->count > 0)) {
351
352 op->count--;
353 if (!op->count && (op->flags & TX_COUNTEVT)) {
354
355 /* create notification to user */
356 msg_head.opcode = TX_EXPIRED;
357 msg_head.flags = op->flags;
358 msg_head.count = op->count;
359 msg_head.ival1 = op->ival1;
360 msg_head.ival2 = op->ival2;
361 msg_head.can_id = op->can_id;
362 msg_head.nframes = 0;
363
364 bcm_send_to_user(op, &msg_head, NULL, 0);
365 }
366 }
367
368 if (op->kt_ival1.tv64 && (op->count > 0)) {
369
370 /* send (next) frame */
371 bcm_can_tx(op);
372 hrtimer_start(&op->timer,
373 ktime_add(ktime_get(), op->kt_ival1),
374 HRTIMER_MODE_ABS);
375
376 } else {
377 if (op->kt_ival2.tv64) {
378
379 /* send (next) frame */
380 bcm_can_tx(op);
381 hrtimer_start(&op->timer,
382 ktime_add(ktime_get(), op->kt_ival2),
383 HRTIMER_MODE_ABS);
384 }
385 }
386 }
387
388 /*
389 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
390 */
391 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
392 {
393 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
394
395 tasklet_schedule(&op->tsklet);
396
397 return HRTIMER_NORESTART;
398 }
399
400 /*
401 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
402 */
403 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
404 {
405 struct bcm_msg_head head;
406
407 /* update statistics */
408 op->frames_filtered++;
409
410 /* prevent statistics overflow */
411 if (op->frames_filtered > ULONG_MAX/100)
412 op->frames_filtered = op->frames_abs = 0;
413
414 /* this element is not throttled anymore */
415 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
416
417 head.opcode = RX_CHANGED;
418 head.flags = op->flags;
419 head.count = op->count;
420 head.ival1 = op->ival1;
421 head.ival2 = op->ival2;
422 head.can_id = op->can_id;
423 head.nframes = 1;
424
425 bcm_send_to_user(op, &head, data, 1);
426 }
427
428 /*
429 * bcm_rx_update_and_send - process a detected relevant receive content change
430 * 1. update the last received data
431 * 2. send a notification to the user (if possible)
432 */
433 static void bcm_rx_update_and_send(struct bcm_op *op,
434 struct can_frame *lastdata,
435 const struct can_frame *rxdata)
436 {
437 memcpy(lastdata, rxdata, CFSIZ);
438
439 /* mark as used and throttled by default */
440 lastdata->can_dlc |= (RX_RECV|RX_THR);
441
442 /* throtteling mode inactive ? */
443 if (!op->kt_ival2.tv64) {
444 /* send RX_CHANGED to the user immediately */
445 bcm_rx_changed(op, lastdata);
446 return;
447 }
448
449 /* with active throttling timer we are just done here */
450 if (hrtimer_active(&op->thrtimer))
451 return;
452
453 /* first receiption with enabled throttling mode */
454 if (!op->kt_lastmsg.tv64)
455 goto rx_changed_settime;
456
457 /* got a second frame inside a potential throttle period? */
458 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
459 ktime_to_us(op->kt_ival2)) {
460 /* do not send the saved data - only start throttle timer */
461 hrtimer_start(&op->thrtimer,
462 ktime_add(op->kt_lastmsg, op->kt_ival2),
463 HRTIMER_MODE_ABS);
464 return;
465 }
466
467 /* the gap was that big, that throttling was not needed here */
468 rx_changed_settime:
469 bcm_rx_changed(op, lastdata);
470 op->kt_lastmsg = ktime_get();
471 }
472
473 /*
474 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
475 * received data stored in op->last_frames[]
476 */
477 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
478 const struct can_frame *rxdata)
479 {
480 /*
481 * no one uses the MSBs of can_dlc for comparation,
482 * so we use it here to detect the first time of reception
483 */
484
485 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
486 /* received data for the first time => send update to user */
487 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
488 return;
489 }
490
491 /* do a real check in can_frame data section */
492
493 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
494 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
495 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
496 return;
497 }
498
499 if (op->flags & RX_CHECK_DLC) {
500 /* do a real check in can_frame dlc */
501 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
502 BCM_CAN_DLC_MASK)) {
503 bcm_rx_update_and_send(op, &op->last_frames[index],
504 rxdata);
505 return;
506 }
507 }
508 }
509
510 /*
511 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
512 */
513 static void bcm_rx_starttimer(struct bcm_op *op)
514 {
515 if (op->flags & RX_NO_AUTOTIMER)
516 return;
517
518 if (op->kt_ival1.tv64)
519 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
520 }
521
522 static void bcm_rx_timeout_tsklet(unsigned long data)
523 {
524 struct bcm_op *op = (struct bcm_op *)data;
525 struct bcm_msg_head msg_head;
526
527 /* create notification to user */
528 msg_head.opcode = RX_TIMEOUT;
529 msg_head.flags = op->flags;
530 msg_head.count = op->count;
531 msg_head.ival1 = op->ival1;
532 msg_head.ival2 = op->ival2;
533 msg_head.can_id = op->can_id;
534 msg_head.nframes = 0;
535
536 bcm_send_to_user(op, &msg_head, NULL, 0);
537 }
538
539 /*
540 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
541 */
542 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
543 {
544 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
545
546 /* schedule before NET_RX_SOFTIRQ */
547 tasklet_hi_schedule(&op->tsklet);
548
549 /* no restart of the timer is done here! */
550
551 /* if user wants to be informed, when cyclic CAN-Messages come back */
552 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
553 /* clear received can_frames to indicate 'nothing received' */
554 memset(op->last_frames, 0, op->nframes * CFSIZ);
555 }
556
557 return HRTIMER_NORESTART;
558 }
559
560 /*
561 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
562 */
563 static inline int bcm_rx_do_flush(struct bcm_op *op, int update,
564 unsigned 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 unsigned 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 unsigned 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 unsigned int i;
835 int err;
836
837 /* we need a real device to send frames */
838 if (!ifindex)
839 return -ENODEV;
840
841 /* check nframes boundaries - we need at least one can_frame */
842 if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES)
843 return -EINVAL;
844
845 /* check the given can_id */
846 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
847
848 if (op) {
849 /* update existing BCM operation */
850
851 /*
852 * Do we need more space for the can_frames than currently
853 * allocated? -> This is a _really_ unusual use-case and
854 * therefore (complexity / locking) it is not supported.
855 */
856 if (msg_head->nframes > op->nframes)
857 return -E2BIG;
858
859 /* update can_frames content */
860 for (i = 0; i < msg_head->nframes; i++) {
861 err = memcpy_fromiovec((u8 *)&op->frames[i],
862 msg->msg_iov, CFSIZ);
863
864 if (op->frames[i].can_dlc > 8)
865 err = -EINVAL;
866
867 if (err < 0)
868 return err;
869
870 if (msg_head->flags & TX_CP_CAN_ID) {
871 /* copy can_id into frame */
872 op->frames[i].can_id = msg_head->can_id;
873 }
874 }
875
876 } else {
877 /* insert new BCM operation for the given can_id */
878
879 op = kzalloc(OPSIZ, GFP_KERNEL);
880 if (!op)
881 return -ENOMEM;
882
883 op->can_id = msg_head->can_id;
884
885 /* create array for can_frames and copy the data */
886 if (msg_head->nframes > 1) {
887 op->frames = kmalloc(msg_head->nframes * CFSIZ,
888 GFP_KERNEL);
889 if (!op->frames) {
890 kfree(op);
891 return -ENOMEM;
892 }
893 } else
894 op->frames = &op->sframe;
895
896 for (i = 0; i < msg_head->nframes; i++) {
897 err = memcpy_fromiovec((u8 *)&op->frames[i],
898 msg->msg_iov, CFSIZ);
899
900 if (op->frames[i].can_dlc > 8)
901 err = -EINVAL;
902
903 if (err < 0) {
904 if (op->frames != &op->sframe)
905 kfree(op->frames);
906 kfree(op);
907 return err;
908 }
909
910 if (msg_head->flags & TX_CP_CAN_ID) {
911 /* copy can_id into frame */
912 op->frames[i].can_id = msg_head->can_id;
913 }
914 }
915
916 /* tx_ops never compare with previous received messages */
917 op->last_frames = NULL;
918
919 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
920 op->sk = sk;
921 op->ifindex = ifindex;
922
923 /* initialize uninitialized (kzalloc) structure */
924 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
925 op->timer.function = bcm_tx_timeout_handler;
926
927 /* initialize tasklet for tx countevent notification */
928 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
929 (unsigned long) op);
930
931 /* currently unused in tx_ops */
932 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
933
934 /* add this bcm_op to the list of the tx_ops */
935 list_add(&op->list, &bo->tx_ops);
936
937 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
938
939 if (op->nframes != msg_head->nframes) {
940 op->nframes = msg_head->nframes;
941 /* start multiple frame transmission with index 0 */
942 op->currframe = 0;
943 }
944
945 /* check flags */
946
947 op->flags = msg_head->flags;
948
949 if (op->flags & TX_RESET_MULTI_IDX) {
950 /* start multiple frame transmission with index 0 */
951 op->currframe = 0;
952 }
953
954 if (op->flags & SETTIMER) {
955 /* set timer values */
956 op->count = msg_head->count;
957 op->ival1 = msg_head->ival1;
958 op->ival2 = msg_head->ival2;
959 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
960 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
961
962 /* disable an active timer due to zero values? */
963 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
964 hrtimer_cancel(&op->timer);
965 }
966
967 if ((op->flags & STARTTIMER) &&
968 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) {
969
970 /* spec: send can_frame when starting timer */
971 op->flags |= TX_ANNOUNCE;
972
973 if (op->kt_ival1.tv64 && (op->count > 0)) {
974 /* op->count-- is done in bcm_tx_timeout_handler */
975 hrtimer_start(&op->timer, op->kt_ival1,
976 HRTIMER_MODE_REL);
977 } else
978 hrtimer_start(&op->timer, op->kt_ival2,
979 HRTIMER_MODE_REL);
980 }
981
982 if (op->flags & TX_ANNOUNCE)
983 bcm_can_tx(op);
984
985 return msg_head->nframes * CFSIZ + MHSIZ;
986 }
987
988 /*
989 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
990 */
991 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
992 int ifindex, struct sock *sk)
993 {
994 struct bcm_sock *bo = bcm_sk(sk);
995 struct bcm_op *op;
996 int do_rx_register;
997 int err = 0;
998
999 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
1000 /* be robust against wrong usage ... */
1001 msg_head->flags |= RX_FILTER_ID;
1002 /* ignore trailing garbage */
1003 msg_head->nframes = 0;
1004 }
1005
1006 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1007 if (msg_head->nframes > MAX_NFRAMES + 1)
1008 return -EINVAL;
1009
1010 if ((msg_head->flags & RX_RTR_FRAME) &&
1011 ((msg_head->nframes != 1) ||
1012 (!(msg_head->can_id & CAN_RTR_FLAG))))
1013 return -EINVAL;
1014
1015 /* check the given can_id */
1016 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
1017 if (op) {
1018 /* update existing BCM operation */
1019
1020 /*
1021 * Do we need more space for the can_frames than currently
1022 * allocated? -> This is a _really_ unusual use-case and
1023 * therefore (complexity / locking) it is not supported.
1024 */
1025 if (msg_head->nframes > op->nframes)
1026 return -E2BIG;
1027
1028 if (msg_head->nframes) {
1029 /* update can_frames content */
1030 err = memcpy_fromiovec((u8 *)op->frames,
1031 msg->msg_iov,
1032 msg_head->nframes * CFSIZ);
1033 if (err < 0)
1034 return err;
1035
1036 /* clear last_frames to indicate 'nothing received' */
1037 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
1038 }
1039
1040 op->nframes = msg_head->nframes;
1041
1042 /* Only an update -> do not call can_rx_register() */
1043 do_rx_register = 0;
1044
1045 } else {
1046 /* insert new BCM operation for the given can_id */
1047 op = kzalloc(OPSIZ, GFP_KERNEL);
1048 if (!op)
1049 return -ENOMEM;
1050
1051 op->can_id = msg_head->can_id;
1052 op->nframes = msg_head->nframes;
1053
1054 if (msg_head->nframes > 1) {
1055 /* create array for can_frames and copy the data */
1056 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1057 GFP_KERNEL);
1058 if (!op->frames) {
1059 kfree(op);
1060 return -ENOMEM;
1061 }
1062
1063 /* create and init array for received can_frames */
1064 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1065 GFP_KERNEL);
1066 if (!op->last_frames) {
1067 kfree(op->frames);
1068 kfree(op);
1069 return -ENOMEM;
1070 }
1071
1072 } else {
1073 op->frames = &op->sframe;
1074 op->last_frames = &op->last_sframe;
1075 }
1076
1077 if (msg_head->nframes) {
1078 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1079 msg_head->nframes * CFSIZ);
1080 if (err < 0) {
1081 if (op->frames != &op->sframe)
1082 kfree(op->frames);
1083 if (op->last_frames != &op->last_sframe)
1084 kfree(op->last_frames);
1085 kfree(op);
1086 return err;
1087 }
1088 }
1089
1090 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1091 op->sk = sk;
1092 op->ifindex = ifindex;
1093
1094 /* initialize uninitialized (kzalloc) structure */
1095 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1096 op->timer.function = bcm_rx_timeout_handler;
1097
1098 /* initialize tasklet for rx timeout notification */
1099 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
1100 (unsigned long) op);
1101
1102 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1103 op->thrtimer.function = bcm_rx_thr_handler;
1104
1105 /* initialize tasklet for rx throttle handling */
1106 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
1107 (unsigned long) op);
1108
1109 /* add this bcm_op to the list of the rx_ops */
1110 list_add(&op->list, &bo->rx_ops);
1111
1112 /* call can_rx_register() */
1113 do_rx_register = 1;
1114
1115 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1116
1117 /* check flags */
1118 op->flags = msg_head->flags;
1119
1120 if (op->flags & RX_RTR_FRAME) {
1121
1122 /* no timers in RTR-mode */
1123 hrtimer_cancel(&op->thrtimer);
1124 hrtimer_cancel(&op->timer);
1125
1126 /*
1127 * funny feature in RX(!)_SETUP only for RTR-mode:
1128 * copy can_id into frame BUT without RTR-flag to
1129 * prevent a full-load-loopback-test ... ;-]
1130 */
1131 if ((op->flags & TX_CP_CAN_ID) ||
1132 (op->frames[0].can_id == op->can_id))
1133 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1134
1135 } else {
1136 if (op->flags & SETTIMER) {
1137
1138 /* set timer value */
1139 op->ival1 = msg_head->ival1;
1140 op->ival2 = msg_head->ival2;
1141 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1142 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1143
1144 /* disable an active timer due to zero value? */
1145 if (!op->kt_ival1.tv64)
1146 hrtimer_cancel(&op->timer);
1147
1148 /*
1149 * In any case cancel the throttle timer, flush
1150 * potentially blocked msgs and reset throttle handling
1151 */
1152 op->kt_lastmsg = ktime_set(0, 0);
1153 hrtimer_cancel(&op->thrtimer);
1154 bcm_rx_thr_flush(op, 1);
1155 }
1156
1157 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
1158 hrtimer_start(&op->timer, op->kt_ival1,
1159 HRTIMER_MODE_REL);
1160 }
1161
1162 /* now we can register for can_ids, if we added a new bcm_op */
1163 if (do_rx_register) {
1164 if (ifindex) {
1165 struct net_device *dev;
1166
1167 dev = dev_get_by_index(&init_net, ifindex);
1168 if (dev) {
1169 err = can_rx_register(dev, op->can_id,
1170 REGMASK(op->can_id),
1171 bcm_rx_handler, op,
1172 "bcm");
1173
1174 op->rx_reg_dev = dev;
1175 dev_put(dev);
1176 }
1177
1178 } else
1179 err = can_rx_register(NULL, op->can_id,
1180 REGMASK(op->can_id),
1181 bcm_rx_handler, op, "bcm");
1182 if (err) {
1183 /* this bcm rx op is broken -> remove it */
1184 list_del(&op->list);
1185 bcm_remove_op(op);
1186 return err;
1187 }
1188 }
1189
1190 return msg_head->nframes * CFSIZ + MHSIZ;
1191 }
1192
1193 /*
1194 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1195 */
1196 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1197 {
1198 struct sk_buff *skb;
1199 struct net_device *dev;
1200 int err;
1201
1202 /* we need a real device to send frames */
1203 if (!ifindex)
1204 return -ENODEV;
1205
1206 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1207
1208 if (!skb)
1209 return -ENOMEM;
1210
1211 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1212 if (err < 0) {
1213 kfree_skb(skb);
1214 return err;
1215 }
1216
1217 dev = dev_get_by_index(&init_net, ifindex);
1218 if (!dev) {
1219 kfree_skb(skb);
1220 return -ENODEV;
1221 }
1222
1223 skb->dev = dev;
1224 skb->sk = sk;
1225 err = can_send(skb, 1); /* send with loopback */
1226 dev_put(dev);
1227
1228 if (err)
1229 return err;
1230
1231 return CFSIZ + MHSIZ;
1232 }
1233
1234 /*
1235 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1236 */
1237 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1238 struct msghdr *msg, size_t size)
1239 {
1240 struct sock *sk = sock->sk;
1241 struct bcm_sock *bo = bcm_sk(sk);
1242 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1243 struct bcm_msg_head msg_head;
1244 int ret; /* read bytes or error codes as return value */
1245
1246 if (!bo->bound)
1247 return -ENOTCONN;
1248
1249 /* check for valid message length from userspace */
1250 if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
1251 return -EINVAL;
1252
1253 /* check for alternative ifindex for this bcm_op */
1254
1255 if (!ifindex && msg->msg_name) {
1256 /* no bound device as default => check msg_name */
1257 struct sockaddr_can *addr =
1258 (struct sockaddr_can *)msg->msg_name;
1259
1260 if (addr->can_family != AF_CAN)
1261 return -EINVAL;
1262
1263 /* ifindex from sendto() */
1264 ifindex = addr->can_ifindex;
1265
1266 if (ifindex) {
1267 struct net_device *dev;
1268
1269 dev = dev_get_by_index(&init_net, ifindex);
1270 if (!dev)
1271 return -ENODEV;
1272
1273 if (dev->type != ARPHRD_CAN) {
1274 dev_put(dev);
1275 return -ENODEV;
1276 }
1277
1278 dev_put(dev);
1279 }
1280 }
1281
1282 /* read message head information */
1283
1284 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1285 if (ret < 0)
1286 return ret;
1287
1288 lock_sock(sk);
1289
1290 switch (msg_head.opcode) {
1291
1292 case TX_SETUP:
1293 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1294 break;
1295
1296 case RX_SETUP:
1297 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1298 break;
1299
1300 case TX_DELETE:
1301 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1302 ret = MHSIZ;
1303 else
1304 ret = -EINVAL;
1305 break;
1306
1307 case RX_DELETE:
1308 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1309 ret = MHSIZ;
1310 else
1311 ret = -EINVAL;
1312 break;
1313
1314 case TX_READ:
1315 /* reuse msg_head for the reply to TX_READ */
1316 msg_head.opcode = TX_STATUS;
1317 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1318 break;
1319
1320 case RX_READ:
1321 /* reuse msg_head for the reply to RX_READ */
1322 msg_head.opcode = RX_STATUS;
1323 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1324 break;
1325
1326 case TX_SEND:
1327 /* we need exactly one can_frame behind the msg head */
1328 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
1329 ret = -EINVAL;
1330 else
1331 ret = bcm_tx_send(msg, ifindex, sk);
1332 break;
1333
1334 default:
1335 ret = -EINVAL;
1336 break;
1337 }
1338
1339 release_sock(sk);
1340
1341 return ret;
1342 }
1343
1344 /*
1345 * notification handler for netdevice status changes
1346 */
1347 static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1348 void *data)
1349 {
1350 struct net_device *dev = (struct net_device *)data;
1351 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1352 struct sock *sk = &bo->sk;
1353 struct bcm_op *op;
1354 int notify_enodev = 0;
1355
1356 if (!net_eq(dev_net(dev), &init_net))
1357 return NOTIFY_DONE;
1358
1359 if (dev->type != ARPHRD_CAN)
1360 return NOTIFY_DONE;
1361
1362 switch (msg) {
1363
1364 case NETDEV_UNREGISTER:
1365 lock_sock(sk);
1366
1367 /* remove device specific receive entries */
1368 list_for_each_entry(op, &bo->rx_ops, list)
1369 if (op->rx_reg_dev == dev)
1370 bcm_rx_unreg(dev, op);
1371
1372 /* remove device reference, if this is our bound device */
1373 if (bo->bound && bo->ifindex == dev->ifindex) {
1374 bo->bound = 0;
1375 bo->ifindex = 0;
1376 notify_enodev = 1;
1377 }
1378
1379 release_sock(sk);
1380
1381 if (notify_enodev) {
1382 sk->sk_err = ENODEV;
1383 if (!sock_flag(sk, SOCK_DEAD))
1384 sk->sk_error_report(sk);
1385 }
1386 break;
1387
1388 case NETDEV_DOWN:
1389 if (bo->bound && bo->ifindex == dev->ifindex) {
1390 sk->sk_err = ENETDOWN;
1391 if (!sock_flag(sk, SOCK_DEAD))
1392 sk->sk_error_report(sk);
1393 }
1394 }
1395
1396 return NOTIFY_DONE;
1397 }
1398
1399 /*
1400 * initial settings for all BCM sockets to be set at socket creation time
1401 */
1402 static int bcm_init(struct sock *sk)
1403 {
1404 struct bcm_sock *bo = bcm_sk(sk);
1405
1406 bo->bound = 0;
1407 bo->ifindex = 0;
1408 bo->dropped_usr_msgs = 0;
1409 bo->bcm_proc_read = NULL;
1410
1411 INIT_LIST_HEAD(&bo->tx_ops);
1412 INIT_LIST_HEAD(&bo->rx_ops);
1413
1414 /* set notifier */
1415 bo->notifier.notifier_call = bcm_notifier;
1416
1417 register_netdevice_notifier(&bo->notifier);
1418
1419 return 0;
1420 }
1421
1422 /*
1423 * standard socket functions
1424 */
1425 static int bcm_release(struct socket *sock)
1426 {
1427 struct sock *sk = sock->sk;
1428 struct bcm_sock *bo;
1429 struct bcm_op *op, *next;
1430
1431 if (sk == NULL)
1432 return 0;
1433
1434 bo = bcm_sk(sk);
1435
1436 /* remove bcm_ops, timer, rx_unregister(), etc. */
1437
1438 unregister_netdevice_notifier(&bo->notifier);
1439
1440 lock_sock(sk);
1441
1442 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1443 bcm_remove_op(op);
1444
1445 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1446 /*
1447 * Don't care if we're bound or not (due to netdev problems)
1448 * can_rx_unregister() is always a save thing to do here.
1449 */
1450 if (op->ifindex) {
1451 /*
1452 * Only remove subscriptions that had not
1453 * been removed due to NETDEV_UNREGISTER
1454 * in bcm_notifier()
1455 */
1456 if (op->rx_reg_dev) {
1457 struct net_device *dev;
1458
1459 dev = dev_get_by_index(&init_net, op->ifindex);
1460 if (dev) {
1461 bcm_rx_unreg(dev, op);
1462 dev_put(dev);
1463 }
1464 }
1465 } else
1466 can_rx_unregister(NULL, op->can_id,
1467 REGMASK(op->can_id),
1468 bcm_rx_handler, op);
1469
1470 bcm_remove_op(op);
1471 }
1472
1473 /* remove procfs entry */
1474 if (proc_dir && bo->bcm_proc_read)
1475 remove_proc_entry(bo->procname, proc_dir);
1476
1477 /* remove device reference */
1478 if (bo->bound) {
1479 bo->bound = 0;
1480 bo->ifindex = 0;
1481 }
1482
1483 sock_orphan(sk);
1484 sock->sk = NULL;
1485
1486 release_sock(sk);
1487 sock_put(sk);
1488
1489 return 0;
1490 }
1491
1492 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1493 int flags)
1494 {
1495 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1496 struct sock *sk = sock->sk;
1497 struct bcm_sock *bo = bcm_sk(sk);
1498
1499 if (bo->bound)
1500 return -EISCONN;
1501
1502 /* bind a device to this socket */
1503 if (addr->can_ifindex) {
1504 struct net_device *dev;
1505
1506 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1507 if (!dev)
1508 return -ENODEV;
1509
1510 if (dev->type != ARPHRD_CAN) {
1511 dev_put(dev);
1512 return -ENODEV;
1513 }
1514
1515 bo->ifindex = dev->ifindex;
1516 dev_put(dev);
1517
1518 } else {
1519 /* no interface reference for ifindex = 0 ('any' CAN device) */
1520 bo->ifindex = 0;
1521 }
1522
1523 bo->bound = 1;
1524
1525 if (proc_dir) {
1526 /* unique socket address as filename */
1527 sprintf(bo->procname, "%lu", sock_i_ino(sk));
1528 bo->bcm_proc_read = proc_create_data(bo->procname, 0644,
1529 proc_dir,
1530 &bcm_proc_fops, sk);
1531 }
1532
1533 return 0;
1534 }
1535
1536 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1537 struct msghdr *msg, size_t size, int flags)
1538 {
1539 struct sock *sk = sock->sk;
1540 struct sk_buff *skb;
1541 int error = 0;
1542 int noblock;
1543 int err;
1544
1545 noblock = flags & MSG_DONTWAIT;
1546 flags &= ~MSG_DONTWAIT;
1547 skb = skb_recv_datagram(sk, flags, noblock, &error);
1548 if (!skb)
1549 return error;
1550
1551 if (skb->len < size)
1552 size = skb->len;
1553
1554 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1555 if (err < 0) {
1556 skb_free_datagram(sk, skb);
1557 return err;
1558 }
1559
1560 sock_recv_timestamp(msg, sk, skb);
1561
1562 if (msg->msg_name) {
1563 msg->msg_namelen = sizeof(struct sockaddr_can);
1564 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1565 }
1566
1567 skb_free_datagram(sk, skb);
1568
1569 return size;
1570 }
1571
1572 static struct proto_ops bcm_ops __read_mostly = {
1573 .family = PF_CAN,
1574 .release = bcm_release,
1575 .bind = sock_no_bind,
1576 .connect = bcm_connect,
1577 .socketpair = sock_no_socketpair,
1578 .accept = sock_no_accept,
1579 .getname = sock_no_getname,
1580 .poll = datagram_poll,
1581 .ioctl = NULL, /* use can_ioctl() from af_can.c */
1582 .listen = sock_no_listen,
1583 .shutdown = sock_no_shutdown,
1584 .setsockopt = sock_no_setsockopt,
1585 .getsockopt = sock_no_getsockopt,
1586 .sendmsg = bcm_sendmsg,
1587 .recvmsg = bcm_recvmsg,
1588 .mmap = sock_no_mmap,
1589 .sendpage = sock_no_sendpage,
1590 };
1591
1592 static struct proto bcm_proto __read_mostly = {
1593 .name = "CAN_BCM",
1594 .owner = THIS_MODULE,
1595 .obj_size = sizeof(struct bcm_sock),
1596 .init = bcm_init,
1597 };
1598
1599 static struct can_proto bcm_can_proto __read_mostly = {
1600 .type = SOCK_DGRAM,
1601 .protocol = CAN_BCM,
1602 .capability = -1,
1603 .ops = &bcm_ops,
1604 .prot = &bcm_proto,
1605 };
1606
1607 static int __init bcm_module_init(void)
1608 {
1609 int err;
1610
1611 printk(banner);
1612
1613 err = can_proto_register(&bcm_can_proto);
1614 if (err < 0) {
1615 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1616 return err;
1617 }
1618
1619 /* create /proc/net/can-bcm directory */
1620 proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
1621 return 0;
1622 }
1623
1624 static void __exit bcm_module_exit(void)
1625 {
1626 can_proto_unregister(&bcm_can_proto);
1627
1628 if (proc_dir)
1629 proc_net_remove(&init_net, "can-bcm");
1630 }
1631
1632 module_init(bcm_module_init);
1633 module_exit(bcm_module_exit);
1634
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