2 * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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
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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.
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.
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.
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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40 * Send feedback to <socketcan-users@lists.berlios.de>
44 #include <linux/module.h>
45 #include <linux/version.h>
46 #include <linux/init.h>
47 #include <linux/interrupt.h>
48 #include <linux/hrtimer.h>
49 #include <linux/list.h>
50 #include <linux/proc_fs.h>
51 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
52 #include <linux/seq_file.h>
54 #include <linux/uio.h>
55 #include <linux/net.h>
56 #include <linux/netdevice.h>
57 #include <linux/socket.h>
58 #include <linux/if_arp.h>
59 #include <linux/skbuff.h>
60 #include <socketcan/can.h>
61 #include <socketcan/can/core.h>
62 #include <socketcan/can/bcm.h>
64 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
65 #include <net/net_namespace.h>
67 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
71 #include <socketcan/can/version.h> /* for RCSID. Removed by mkpatch script */
75 * To send multiple CAN frame content within TX_SETUP or to filter
76 * CAN messages with multiplex index within RX_SETUP, the number of
77 * different filters is limited to 256 due to the one byte index value.
79 #define MAX_NFRAMES 256
81 /* use of last_frames[index].can_dlc */
82 #define RX_RECV 0x40 /* received data for this element */
83 #define RX_THR 0x80 /* element not been sent due to throttle feature */
84 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
86 /* get best masking value for can_rx_register() for a given single can_id */
87 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
88 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
89 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
91 #define CAN_BCM_VERSION CAN_VERSION
92 static __initdata const char banner[] = KERN_INFO
93 "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n";
95 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
96 MODULE_LICENSE("Dual BSD/GPL");
97 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
98 MODULE_ALIAS("can-proto-2");
100 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,22)
101 #error This code only supports Kernel versions 2.6.22+
102 #error For older 2.6 Kernels please use bcm-prior-2-6-22.c instead of bcm.c
105 /* easy access to can_frame payload */
106 static inline u64 GET_U64(const struct can_frame *cp)
108 return *(u64 *)cp->data;
112 struct list_head list;
116 unsigned long frames_abs, frames_filtered;
117 struct timeval ival1, ival2;
118 struct hrtimer timer, thrtimer;
119 struct tasklet_struct tsklet, thrtsklet;
120 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg;
125 struct can_frame *frames;
126 struct can_frame *last_frames;
127 struct can_frame sframe;
128 struct can_frame last_sframe;
130 struct net_device *rx_reg_dev;
133 static struct proc_dir_entry *proc_dir;
139 struct notifier_block notifier;
140 struct list_head rx_ops;
141 struct list_head tx_ops;
142 unsigned long dropped_usr_msgs;
143 struct proc_dir_entry *bcm_proc_read;
144 char procname [32]; /* inode number in decimal with \0 */
147 static inline struct bcm_sock *bcm_sk(const struct sock *sk)
149 return (struct bcm_sock *)sk;
152 #define CFSIZ sizeof(struct can_frame)
153 #define OPSIZ sizeof(struct bcm_op)
154 #define MHSIZ sizeof(struct bcm_msg_head)
159 static char *bcm_proc_getifname(char *result, int ifindex)
161 struct net_device *dev;
166 read_lock(&dev_base_lock);
167 dev = __dev_get_by_index(&init_net, ifindex);
169 strcpy(result, dev->name);
171 strcpy(result, "???");
172 read_unlock(&dev_base_lock);
177 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
178 static int bcm_proc_show(struct seq_file *m, void *v)
180 char ifname[IFNAMSIZ];
181 struct sock *sk = (struct sock *)m->private;
182 struct bcm_sock *bo = bcm_sk(sk);
185 #if LINUX_VERSION_CODE < KERNEL_VERSION(3,0,0)
186 seq_printf(m, ">>> socket %p", sk->sk_socket);
187 seq_printf(m, " / sk %p", sk);
188 seq_printf(m, " / bo %p", bo);
190 seq_printf(m, ">>> socket %pK", sk->sk_socket);
191 seq_printf(m, " / sk %pK", sk);
192 seq_printf(m, " / bo %pK", bo);
194 seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs);
195 seq_printf(m, " / bound %s", bcm_proc_getifname(ifname, bo->ifindex));
196 seq_printf(m, " <<<\n");
198 list_for_each_entry(op, &bo->rx_ops, list) {
200 unsigned long reduction;
202 /* print only active entries & prevent division by zero */
206 seq_printf(m, "rx_op: %03X %-5s ",
207 op->can_id, bcm_proc_getifname(ifname, op->ifindex));
208 seq_printf(m, "[%u]%c ", op->nframes,
209 (op->flags & RX_CHECK_DLC)?'d':' ');
210 if (op->kt_ival1.tv64)
211 seq_printf(m, "timeo=%lld ",
213 ktime_to_us(op->kt_ival1));
215 if (op->kt_ival2.tv64)
216 seq_printf(m, "thr=%lld ",
218 ktime_to_us(op->kt_ival2));
220 seq_printf(m, "# recv %ld (%ld) => reduction: ",
221 op->frames_filtered, op->frames_abs);
223 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
225 seq_printf(m, "%s%ld%%\n",
226 (reduction == 100)?"near ":"", reduction);
229 list_for_each_entry(op, &bo->tx_ops, list) {
231 seq_printf(m, "tx_op: %03X %s [%u] ",
233 bcm_proc_getifname(ifname, op->ifindex),
236 if (op->kt_ival1.tv64)
237 seq_printf(m, "t1=%lld ",
238 (long long) ktime_to_us(op->kt_ival1));
240 if (op->kt_ival2.tv64)
241 seq_printf(m, "t2=%lld ",
242 (long long) ktime_to_us(op->kt_ival2));
244 seq_printf(m, "# sent %ld\n", op->frames_abs);
250 static int bcm_proc_open(struct inode *inode, struct file *file)
252 return single_open(file, bcm_proc_show, PDE(inode)->data);
255 static const struct file_operations bcm_proc_fops = {
256 .owner = THIS_MODULE,
257 .open = bcm_proc_open,
260 .release = single_release,
263 static int bcm_read_proc(char *page, char **start, off_t off,
264 int count, int *eof, void *data)
266 char ifname[IFNAMSIZ];
268 struct sock *sk = (struct sock *)data;
269 struct bcm_sock *bo = bcm_sk(sk);
272 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
274 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
275 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
276 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
277 bo->dropped_usr_msgs);
278 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
279 bcm_proc_getifname(ifname, bo->ifindex));
280 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n");
282 list_for_each_entry(op, &bo->rx_ops, list) {
284 unsigned long reduction;
286 /* print only active entries & prevent division by zero */
290 len += snprintf(page + len, PAGE_SIZE - len,
292 op->can_id, bcm_proc_getifname(ifname, op->ifindex));
293 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
295 (op->flags & RX_CHECK_DLC)?'d':' ');
296 if (op->kt_ival1.tv64)
297 len += snprintf(page + len, PAGE_SIZE - len,
300 ktime_to_us(op->kt_ival1));
302 if (op->kt_ival2.tv64)
303 len += snprintf(page + len, PAGE_SIZE - len,
306 ktime_to_us(op->kt_ival2));
308 len += snprintf(page + len, PAGE_SIZE - len,
309 "# recv %ld (%ld) => reduction: ",
310 op->frames_filtered, op->frames_abs);
312 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
314 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
315 (reduction == 100)?"near ":"", reduction);
317 if (len > PAGE_SIZE - 200) {
318 /* mark output cut off */
319 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
324 list_for_each_entry(op, &bo->tx_ops, list) {
326 len += snprintf(page + len, PAGE_SIZE - len,
327 "tx_op: %03X %s [%d] ",
329 bcm_proc_getifname(ifname, op->ifindex),
332 if (op->kt_ival1.tv64)
333 len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ",
334 (long long) ktime_to_us(op->kt_ival1));
336 if (op->kt_ival2.tv64)
337 len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ",
338 (long long) ktime_to_us(op->kt_ival2));
340 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
343 if (len > PAGE_SIZE - 100) {
344 /* mark output cut off */
345 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
350 len += snprintf(page + len, PAGE_SIZE - len, "\n");
358 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
359 * of the given bcm tx op
361 static void bcm_can_tx(struct bcm_op *op)
364 struct net_device *dev;
365 struct can_frame *cf = &op->frames[op->currframe];
367 /* no target device? => exit */
371 dev = dev_get_by_index(&init_net, op->ifindex);
373 /* RFC: should this bcm_op remove itself here? */
377 skb = alloc_skb(CFSIZ, gfp_any());
381 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
383 /* send with loopback */
388 /* update statistics */
392 /* reached last frame? */
393 if (op->currframe >= op->nframes)
400 * bcm_send_to_user - send a BCM message to the userspace
401 * (consisting of bcm_msg_head + x CAN frames)
403 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
404 struct can_frame *frames, int has_timestamp)
407 struct can_frame *firstframe;
408 struct sockaddr_can *addr;
409 struct sock *sk = op->sk;
410 unsigned int datalen = head->nframes * CFSIZ;
413 skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
417 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
420 /* can_frames starting here */
421 firstframe = (struct can_frame *)skb_tail_pointer(skb);
423 memcpy(skb_put(skb, datalen), frames, datalen);
426 * the BCM uses the can_dlc-element of the can_frame
427 * structure for internal purposes. This is only
428 * relevant for updates that are generated by the
429 * BCM, where nframes is 1
431 if (head->nframes == 1)
432 firstframe->can_dlc &= BCM_CAN_DLC_MASK;
436 /* restore rx timestamp */
437 skb->tstamp = op->rx_stamp;
441 * Put the datagram to the queue so that bcm_recvmsg() can
442 * get it from there. We need to pass the interface index to
443 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
444 * containing the interface index.
447 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
448 addr = (struct sockaddr_can *)skb->cb;
449 memset(addr, 0, sizeof(*addr));
450 addr->can_family = AF_CAN;
451 addr->can_ifindex = op->rx_ifindex;
453 err = sock_queue_rcv_skb(sk, skb);
455 struct bcm_sock *bo = bcm_sk(sk);
458 /* don't care about overflows in this statistic */
459 bo->dropped_usr_msgs++;
463 static void bcm_tx_timeout_tsklet(unsigned long data)
465 struct bcm_op *op = (struct bcm_op *)data;
466 struct bcm_msg_head msg_head;
468 if (op->kt_ival1.tv64 && (op->count > 0)) {
471 if (!op->count && (op->flags & TX_COUNTEVT)) {
473 /* create notification to user */
474 msg_head.opcode = TX_EXPIRED;
475 msg_head.flags = op->flags;
476 msg_head.count = op->count;
477 msg_head.ival1 = op->ival1;
478 msg_head.ival2 = op->ival2;
479 msg_head.can_id = op->can_id;
480 msg_head.nframes = 0;
482 bcm_send_to_user(op, &msg_head, NULL, 0);
485 /* send (next) frame */
487 hrtimer_start(&op->timer,
488 ktime_add(ktime_get(), op->kt_ival1),
492 if (op->kt_ival2.tv64) {
494 /* send (next) frame */
496 hrtimer_start(&op->timer,
497 ktime_add(ktime_get(), op->kt_ival2),
504 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
506 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
508 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
510 tasklet_schedule(&op->tsklet);
512 return HRTIMER_NORESTART;
516 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
518 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
520 struct bcm_msg_head head;
522 /* update statistics */
523 op->frames_filtered++;
525 /* prevent statistics overflow */
526 if (op->frames_filtered > ULONG_MAX/100)
527 op->frames_filtered = op->frames_abs = 0;
529 /* this element is not throttled anymore */
530 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
532 head.opcode = RX_CHANGED;
533 head.flags = op->flags;
534 head.count = op->count;
535 head.ival1 = op->ival1;
536 head.ival2 = op->ival2;
537 head.can_id = op->can_id;
540 bcm_send_to_user(op, &head, data, 1);
543 #if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,25)
544 /* is part of linux/hrtimer.h since 2.6.26 */
545 static inline int hrtimer_callback_running(struct hrtimer *timer)
547 return timer->state & HRTIMER_STATE_CALLBACK;
550 #if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,22)
551 static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier)
553 return ktime_to_us(ktime_sub(later, earlier));
557 * bcm_rx_update_and_send - process a detected relevant receive content change
558 * 1. update the last received data
559 * 2. send a notification to the user (if possible)
561 static void bcm_rx_update_and_send(struct bcm_op *op,
562 struct can_frame *lastdata,
563 const struct can_frame *rxdata)
565 memcpy(lastdata, rxdata, CFSIZ);
567 /* mark as used and throttled by default */
568 lastdata->can_dlc |= (RX_RECV|RX_THR);
570 /* throtteling mode inactive ? */
571 if (!op->kt_ival2.tv64) {
572 /* send RX_CHANGED to the user immediately */
573 bcm_rx_changed(op, lastdata);
577 /* with active throttling timer we are just done here */
578 if (hrtimer_active(&op->thrtimer))
581 /* first receiption with enabled throttling mode */
582 if (!op->kt_lastmsg.tv64)
583 goto rx_changed_settime;
585 /* got a second frame inside a potential throttle period? */
586 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
587 ktime_to_us(op->kt_ival2)) {
588 /* do not send the saved data - only start throttle timer */
589 hrtimer_start(&op->thrtimer,
590 ktime_add(op->kt_lastmsg, op->kt_ival2),
595 /* the gap was that big, that throttling was not needed here */
597 bcm_rx_changed(op, lastdata);
598 op->kt_lastmsg = ktime_get();
602 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
603 * received data stored in op->last_frames[]
605 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
606 const struct can_frame *rxdata)
609 * no one uses the MSBs of can_dlc for comparation,
610 * so we use it here to detect the first time of reception
613 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
614 /* received data for the first time => send update to user */
615 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
619 /* do a real check in can_frame data section */
621 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
622 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
623 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
627 if (op->flags & RX_CHECK_DLC) {
628 /* do a real check in can_frame dlc */
629 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
631 bcm_rx_update_and_send(op, &op->last_frames[index],
639 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
641 static void bcm_rx_starttimer(struct bcm_op *op)
643 if (op->flags & RX_NO_AUTOTIMER)
646 if (op->kt_ival1.tv64)
647 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
650 static void bcm_rx_timeout_tsklet(unsigned long data)
652 struct bcm_op *op = (struct bcm_op *)data;
653 struct bcm_msg_head msg_head;
655 /* create notification to user */
656 msg_head.opcode = RX_TIMEOUT;
657 msg_head.flags = op->flags;
658 msg_head.count = op->count;
659 msg_head.ival1 = op->ival1;
660 msg_head.ival2 = op->ival2;
661 msg_head.can_id = op->can_id;
662 msg_head.nframes = 0;
664 bcm_send_to_user(op, &msg_head, NULL, 0);
668 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
670 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
672 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
674 /* schedule before NET_RX_SOFTIRQ */
675 tasklet_hi_schedule(&op->tsklet);
677 /* no restart of the timer is done here! */
679 /* if user wants to be informed, when cyclic CAN-Messages come back */
680 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
681 /* clear received can_frames to indicate 'nothing received' */
682 memset(op->last_frames, 0, op->nframes * CFSIZ);
685 return HRTIMER_NORESTART;
689 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
691 static inline int bcm_rx_do_flush(struct bcm_op *op, int update,
694 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
696 bcm_rx_changed(op, &op->last_frames[index]);
703 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
705 * update == 0 : just check if throttled data is available (any irq context)
706 * update == 1 : check and send throttled data to userspace (soft_irq context)
708 static int bcm_rx_thr_flush(struct bcm_op *op, int update)
712 if (op->nframes > 1) {
715 /* for MUX filter we start at index 1 */
716 for (i = 1; i < op->nframes; i++)
717 updated += bcm_rx_do_flush(op, update, i);
720 /* for RX_FILTER_ID and simple filter */
721 updated += bcm_rx_do_flush(op, update, 0);
727 static void bcm_rx_thr_tsklet(unsigned long data)
729 struct bcm_op *op = (struct bcm_op *)data;
731 /* push the changed data to the userspace */
732 bcm_rx_thr_flush(op, 1);
736 * bcm_rx_thr_handler - the time for blocked content updates is over now:
737 * Check for throttled data and send it to the userspace
739 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
741 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
743 tasklet_schedule(&op->thrtsklet);
745 if (bcm_rx_thr_flush(op, 0)) {
746 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
747 return HRTIMER_RESTART;
749 /* rearm throttle handling */
750 op->kt_lastmsg = ktime_set(0, 0);
751 return HRTIMER_NORESTART;
756 * bcm_rx_handler - handle a CAN frame receiption
758 static void bcm_rx_handler(struct sk_buff *skb, void *data)
760 struct bcm_op *op = (struct bcm_op *)data;
761 const struct can_frame *rxframe = (struct can_frame *)skb->data;
764 /* disable timeout */
765 hrtimer_cancel(&op->timer);
767 if (op->can_id != rxframe->can_id)
770 /* save rx timestamp */
771 op->rx_stamp = skb->tstamp;
772 /* save originator for recvfrom() */
773 op->rx_ifindex = skb->dev->ifindex;
774 /* update statistics */
777 if (op->flags & RX_RTR_FRAME) {
778 /* send reply for RTR-request (placed in op->frames[0]) */
783 if (op->flags & RX_FILTER_ID) {
784 /* the easiest case */
785 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
789 if (op->nframes == 1) {
790 /* simple compare with index 0 */
791 bcm_rx_cmp_to_index(op, 0, rxframe);
795 if (op->nframes > 1) {
799 * find the first multiplex mask that fits.
800 * Remark: The MUX-mask is stored in index 0
803 for (i = 1; i < op->nframes; i++) {
804 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
805 (GET_U64(&op->frames[0]) &
806 GET_U64(&op->frames[i]))) {
807 bcm_rx_cmp_to_index(op, i, rxframe);
814 bcm_rx_starttimer(op);
818 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
820 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
825 list_for_each_entry(op, ops, list) {
826 if ((op->can_id == can_id) && (op->ifindex == ifindex))
833 static void bcm_remove_op(struct bcm_op *op)
835 hrtimer_cancel(&op->timer);
836 hrtimer_cancel(&op->thrtimer);
839 tasklet_kill(&op->tsklet);
841 if (op->thrtsklet.func)
842 tasklet_kill(&op->thrtsklet);
844 if ((op->frames) && (op->frames != &op->sframe))
847 if ((op->last_frames) && (op->last_frames != &op->last_sframe))
848 kfree(op->last_frames);
855 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
857 if (op->rx_reg_dev == dev) {
858 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
861 /* mark as removed subscription */
862 op->rx_reg_dev = NULL;
864 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
865 "mismatch %p %p\n", op->rx_reg_dev, dev);
869 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
871 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
873 struct bcm_op *op, *n;
875 list_for_each_entry_safe(op, n, ops, list) {
876 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
879 * Don't care if we're bound or not (due to netdev
880 * problems) can_rx_unregister() is always a save
885 * Only remove subscriptions that had not
886 * been removed due to NETDEV_UNREGISTER
889 if (op->rx_reg_dev) {
890 struct net_device *dev;
892 dev = dev_get_by_index(&init_net,
895 bcm_rx_unreg(dev, op);
900 can_rx_unregister(NULL, op->can_id,
910 return 0; /* not found */
914 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
916 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
918 struct bcm_op *op, *n;
920 list_for_each_entry_safe(op, n, ops, list) {
921 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
928 return 0; /* not found */
932 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
934 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
937 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
942 /* put current values into msg_head */
943 msg_head->flags = op->flags;
944 msg_head->count = op->count;
945 msg_head->ival1 = op->ival1;
946 msg_head->ival2 = op->ival2;
947 msg_head->nframes = op->nframes;
949 bcm_send_to_user(op, msg_head, op->frames, 0);
955 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
957 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
958 int ifindex, struct sock *sk)
960 struct bcm_sock *bo = bcm_sk(sk);
965 /* we need a real device to send frames */
969 /* check nframes boundaries - we need at least one can_frame */
970 if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES)
973 /* check the given can_id */
974 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
977 /* update existing BCM operation */
980 * Do we need more space for the can_frames than currently
981 * allocated? -> This is a _really_ unusual use-case and
982 * therefore (complexity / locking) it is not supported.
984 if (msg_head->nframes > op->nframes)
987 /* update can_frames content */
988 for (i = 0; i < msg_head->nframes; i++) {
989 err = memcpy_fromiovec((u8 *)&op->frames[i],
990 msg->msg_iov, CFSIZ);
992 if (op->frames[i].can_dlc > 8)
998 if (msg_head->flags & TX_CP_CAN_ID) {
999 /* copy can_id into frame */
1000 op->frames[i].can_id = msg_head->can_id;
1005 /* insert new BCM operation for the given can_id */
1007 op = kzalloc(OPSIZ, GFP_KERNEL);
1011 op->can_id = msg_head->can_id;
1013 /* create array for can_frames and copy the data */
1014 if (msg_head->nframes > 1) {
1015 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1022 op->frames = &op->sframe;
1024 for (i = 0; i < msg_head->nframes; i++) {
1025 err = memcpy_fromiovec((u8 *)&op->frames[i],
1026 msg->msg_iov, CFSIZ);
1028 if (op->frames[i].can_dlc > 8)
1032 if (op->frames != &op->sframe)
1038 if (msg_head->flags & TX_CP_CAN_ID) {
1039 /* copy can_id into frame */
1040 op->frames[i].can_id = msg_head->can_id;
1044 /* tx_ops never compare with previous received messages */
1045 op->last_frames = NULL;
1047 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1049 op->ifindex = ifindex;
1051 /* initialize uninitialized (kzalloc) structure */
1052 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1053 op->timer.function = bcm_tx_timeout_handler;
1055 /* initialize tasklet for tx countevent notification */
1056 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
1057 (unsigned long) op);
1059 /* currently unused in tx_ops */
1060 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1062 /* add this bcm_op to the list of the tx_ops */
1063 list_add(&op->list, &bo->tx_ops);
1065 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
1067 if (op->nframes != msg_head->nframes) {
1068 op->nframes = msg_head->nframes;
1069 /* start multiple frame transmission with index 0 */
1075 op->flags = msg_head->flags;
1077 if (op->flags & TX_RESET_MULTI_IDX) {
1078 /* start multiple frame transmission with index 0 */
1082 if (op->flags & SETTIMER) {
1083 /* set timer values */
1084 op->count = msg_head->count;
1085 op->ival1 = msg_head->ival1;
1086 op->ival2 = msg_head->ival2;
1087 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1088 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1090 /* disable an active timer due to zero values? */
1091 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
1092 hrtimer_cancel(&op->timer);
1095 if ((op->flags & STARTTIMER) &&
1096 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) {
1098 /* spec: send can_frame when starting timer */
1099 op->flags |= TX_ANNOUNCE;
1101 /* only start timer when having more frames than sent below */
1102 if (op->kt_ival1.tv64 && (op->count > 1)) {
1103 /* op->count-- is done in bcm_tx_timeout_tsklet */
1104 hrtimer_start(&op->timer, op->kt_ival1,
1107 hrtimer_start(&op->timer, op->kt_ival2,
1111 if (op->flags & TX_ANNOUNCE) {
1113 if (op->kt_ival1.tv64 && (op->count > 0))
1117 return msg_head->nframes * CFSIZ + MHSIZ;
1121 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
1123 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
1124 int ifindex, struct sock *sk)
1126 struct bcm_sock *bo = bcm_sk(sk);
1131 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
1132 /* be robust against wrong usage ... */
1133 msg_head->flags |= RX_FILTER_ID;
1134 /* ignore trailing garbage */
1135 msg_head->nframes = 0;
1138 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1139 if (msg_head->nframes > MAX_NFRAMES + 1)
1142 if ((msg_head->flags & RX_RTR_FRAME) &&
1143 ((msg_head->nframes != 1) ||
1144 (!(msg_head->can_id & CAN_RTR_FLAG))))
1147 /* check the given can_id */
1148 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
1150 /* update existing BCM operation */
1153 * Do we need more space for the can_frames than currently
1154 * allocated? -> This is a _really_ unusual use-case and
1155 * therefore (complexity / locking) it is not supported.
1157 if (msg_head->nframes > op->nframes)
1160 if (msg_head->nframes) {
1161 /* update can_frames content */
1162 err = memcpy_fromiovec((u8 *)op->frames,
1164 msg_head->nframes * CFSIZ);
1168 /* clear last_frames to indicate 'nothing received' */
1169 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
1172 op->nframes = msg_head->nframes;
1174 /* Only an update -> do not call can_rx_register() */
1178 /* insert new BCM operation for the given can_id */
1179 op = kzalloc(OPSIZ, GFP_KERNEL);
1183 op->can_id = msg_head->can_id;
1184 op->nframes = msg_head->nframes;
1186 if (msg_head->nframes > 1) {
1187 /* create array for can_frames and copy the data */
1188 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1195 /* create and init array for received can_frames */
1196 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1198 if (!op->last_frames) {
1205 op->frames = &op->sframe;
1206 op->last_frames = &op->last_sframe;
1209 if (msg_head->nframes) {
1210 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1211 msg_head->nframes * CFSIZ);
1213 if (op->frames != &op->sframe)
1215 if (op->last_frames != &op->last_sframe)
1216 kfree(op->last_frames);
1222 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1224 op->ifindex = ifindex;
1226 /* initialize uninitialized (kzalloc) structure */
1227 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1228 op->timer.function = bcm_rx_timeout_handler;
1230 /* initialize tasklet for rx timeout notification */
1231 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
1232 (unsigned long) op);
1234 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1235 op->thrtimer.function = bcm_rx_thr_handler;
1237 /* initialize tasklet for rx throttle handling */
1238 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
1239 (unsigned long) op);
1241 /* add this bcm_op to the list of the rx_ops */
1242 list_add(&op->list, &bo->rx_ops);
1244 /* call can_rx_register() */
1247 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1250 op->flags = msg_head->flags;
1252 if (op->flags & RX_RTR_FRAME) {
1254 /* no timers in RTR-mode */
1255 hrtimer_cancel(&op->thrtimer);
1256 hrtimer_cancel(&op->timer);
1259 * funny feature in RX(!)_SETUP only for RTR-mode:
1260 * copy can_id into frame BUT without RTR-flag to
1261 * prevent a full-load-loopback-test ... ;-]
1263 if ((op->flags & TX_CP_CAN_ID) ||
1264 (op->frames[0].can_id == op->can_id))
1265 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1268 if (op->flags & SETTIMER) {
1270 /* set timer value */
1271 op->ival1 = msg_head->ival1;
1272 op->ival2 = msg_head->ival2;
1273 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1274 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1276 /* disable an active timer due to zero value? */
1277 if (!op->kt_ival1.tv64)
1278 hrtimer_cancel(&op->timer);
1281 * In any case cancel the throttle timer, flush
1282 * potentially blocked msgs and reset throttle handling
1284 op->kt_lastmsg = ktime_set(0, 0);
1285 hrtimer_cancel(&op->thrtimer);
1286 bcm_rx_thr_flush(op, 1);
1289 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
1290 hrtimer_start(&op->timer, op->kt_ival1,
1294 /* now we can register for can_ids, if we added a new bcm_op */
1295 if (do_rx_register) {
1297 struct net_device *dev;
1299 dev = dev_get_by_index(&init_net, ifindex);
1301 err = can_rx_register(dev, op->can_id,
1302 REGMASK(op->can_id),
1306 op->rx_reg_dev = dev;
1311 err = can_rx_register(NULL, op->can_id,
1312 REGMASK(op->can_id),
1313 bcm_rx_handler, op, "bcm");
1315 /* this bcm rx op is broken -> remove it */
1316 list_del(&op->list);
1322 return msg_head->nframes * CFSIZ + MHSIZ;
1326 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1328 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1330 struct sk_buff *skb;
1331 struct net_device *dev;
1334 /* we need a real device to send frames */
1338 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1343 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1349 dev = dev_get_by_index(&init_net, ifindex);
1357 err = can_send(skb, 1); /* send with loopback */
1363 return CFSIZ + MHSIZ;
1367 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1369 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1370 struct msghdr *msg, size_t size)
1372 struct sock *sk = sock->sk;
1373 struct bcm_sock *bo = bcm_sk(sk);
1374 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1375 struct bcm_msg_head msg_head;
1376 int ret; /* read bytes or error codes as return value */
1381 /* check for valid message length from userspace */
1382 if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
1385 /* check for alternative ifindex for this bcm_op */
1387 if (!ifindex && msg->msg_name) {
1388 /* no bound device as default => check msg_name */
1389 struct sockaddr_can *addr =
1390 (struct sockaddr_can *)msg->msg_name;
1392 if (msg->msg_namelen < sizeof(*addr))
1395 if (addr->can_family != AF_CAN)
1398 /* ifindex from sendto() */
1399 ifindex = addr->can_ifindex;
1402 struct net_device *dev;
1404 dev = dev_get_by_index(&init_net, ifindex);
1408 if (dev->type != ARPHRD_CAN) {
1417 /* read message head information */
1419 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1425 switch (msg_head.opcode) {
1428 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1432 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1436 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1443 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1450 /* reuse msg_head for the reply to TX_READ */
1451 msg_head.opcode = TX_STATUS;
1452 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1456 /* reuse msg_head for the reply to RX_READ */
1457 msg_head.opcode = RX_STATUS;
1458 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1462 /* we need exactly one can_frame behind the msg head */
1463 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
1466 ret = bcm_tx_send(msg, ifindex, sk);
1480 * notification handler for netdevice status changes
1482 static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1485 struct net_device *dev = (struct net_device *)data;
1486 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1487 struct sock *sk = &bo->sk;
1489 int notify_enodev = 0;
1491 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
1492 if (!net_eq(dev_net(dev), &init_net))
1494 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1495 if (dev->nd_net != &init_net)
1499 if (dev->type != ARPHRD_CAN)
1504 case NETDEV_UNREGISTER:
1507 /* remove device specific receive entries */
1508 list_for_each_entry(op, &bo->rx_ops, list)
1509 if (op->rx_reg_dev == dev)
1510 bcm_rx_unreg(dev, op);
1512 /* remove device reference, if this is our bound device */
1513 if (bo->bound && bo->ifindex == dev->ifindex) {
1521 if (notify_enodev) {
1522 sk->sk_err = ENODEV;
1523 if (!sock_flag(sk, SOCK_DEAD))
1524 sk->sk_error_report(sk);
1529 if (bo->bound && bo->ifindex == dev->ifindex) {
1530 sk->sk_err = ENETDOWN;
1531 if (!sock_flag(sk, SOCK_DEAD))
1532 sk->sk_error_report(sk);
1540 * initial settings for all BCM sockets to be set at socket creation time
1542 static int bcm_init(struct sock *sk)
1544 struct bcm_sock *bo = bcm_sk(sk);
1548 bo->dropped_usr_msgs = 0;
1549 bo->bcm_proc_read = NULL;
1551 INIT_LIST_HEAD(&bo->tx_ops);
1552 INIT_LIST_HEAD(&bo->rx_ops);
1555 bo->notifier.notifier_call = bcm_notifier;
1557 register_netdevice_notifier(&bo->notifier);
1563 * standard socket functions
1565 static int bcm_release(struct socket *sock)
1567 struct sock *sk = sock->sk;
1568 struct bcm_sock *bo;
1569 struct bcm_op *op, *next;
1576 /* remove bcm_ops, timer, rx_unregister(), etc. */
1578 unregister_netdevice_notifier(&bo->notifier);
1582 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1585 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1587 * Don't care if we're bound or not (due to netdev problems)
1588 * can_rx_unregister() is always a save thing to do here.
1592 * Only remove subscriptions that had not
1593 * been removed due to NETDEV_UNREGISTER
1596 if (op->rx_reg_dev) {
1597 struct net_device *dev;
1599 dev = dev_get_by_index(&init_net, op->ifindex);
1601 bcm_rx_unreg(dev, op);
1606 can_rx_unregister(NULL, op->can_id,
1607 REGMASK(op->can_id),
1608 bcm_rx_handler, op);
1613 /* remove procfs entry */
1614 if (proc_dir && bo->bcm_proc_read)
1615 remove_proc_entry(bo->procname, proc_dir);
1617 /* remove device reference */
1632 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1635 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1636 struct sock *sk = sock->sk;
1637 struct bcm_sock *bo = bcm_sk(sk);
1639 if (len < sizeof(*addr))
1645 /* bind a device to this socket */
1646 if (addr->can_ifindex) {
1647 struct net_device *dev;
1649 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1653 if (dev->type != ARPHRD_CAN) {
1658 bo->ifindex = dev->ifindex;
1662 /* no interface reference for ifindex = 0 ('any' CAN device) */
1669 /* unique socket address as filename */
1670 sprintf(bo->procname, "%lu", sock_i_ino(sk));
1671 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
1672 bo->bcm_proc_read = proc_create_data(bo->procname, 0644,
1674 &bcm_proc_fops, sk);
1676 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
1685 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1686 struct msghdr *msg, size_t size, int flags)
1688 struct sock *sk = sock->sk;
1689 struct sk_buff *skb;
1694 noblock = flags & MSG_DONTWAIT;
1695 flags &= ~MSG_DONTWAIT;
1696 skb = skb_recv_datagram(sk, flags, noblock, &error);
1700 if (skb->len < size)
1703 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1705 skb_free_datagram(sk, skb);
1709 sock_recv_timestamp(msg, sk, skb);
1711 if (msg->msg_name) {
1712 msg->msg_namelen = sizeof(struct sockaddr_can);
1713 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1716 skb_free_datagram(sk, skb);
1721 static const struct proto_ops bcm_ops = {
1723 .release = bcm_release,
1724 .bind = sock_no_bind,
1725 .connect = bcm_connect,
1726 .socketpair = sock_no_socketpair,
1727 .accept = sock_no_accept,
1728 .getname = sock_no_getname,
1729 .poll = datagram_poll,
1730 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
1731 .listen = sock_no_listen,
1732 .shutdown = sock_no_shutdown,
1733 .setsockopt = sock_no_setsockopt,
1734 .getsockopt = sock_no_getsockopt,
1735 .sendmsg = bcm_sendmsg,
1736 .recvmsg = bcm_recvmsg,
1737 .mmap = sock_no_mmap,
1738 .sendpage = sock_no_sendpage,
1741 static struct proto bcm_proto __read_mostly = {
1743 .owner = THIS_MODULE,
1744 .obj_size = sizeof(struct bcm_sock),
1748 static const struct can_proto bcm_can_proto = {
1750 .protocol = CAN_BCM,
1751 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,33)
1758 static int __init bcm_module_init(void)
1764 err = can_proto_register(&bcm_can_proto);
1766 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1770 /* create /proc/net/can-bcm directory */
1771 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1772 proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
1774 proc_dir = proc_mkdir("can-bcm", proc_net);
1777 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,30)
1779 proc_dir->owner = THIS_MODULE;
1785 static void __exit bcm_module_exit(void)
1787 can_proto_unregister(&bcm_can_proto);
1790 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1791 proc_net_remove(&init_net, "can-bcm");
1793 proc_net_remove("can-bcm");
1797 module_init(bcm_module_init);
1798 module_exit(bcm_module_exit);