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
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.
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/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>
61 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
64 /* use of last_frames[index].can_dlc */
65 #define RX_RECV 0x40 /* received data for this element */
66 #define RX_THR 0x80 /* element not been sent due to throttle feature */
67 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
69 /* get best masking value for can_rx_register() for a given single can_id */
70 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
71 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
72 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
74 #define CAN_BCM_VERSION CAN_VERSION
75 static __initdata const char banner[] = KERN_INFO
76 "can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n";
78 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
79 MODULE_LICENSE("Dual BSD/GPL");
80 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
82 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
83 #error This code only supports Kernel versions _below_ 2.6.22
84 #error For 2.6.22+ Kernels please use bcm.c instead of bcm-prior-2-6-22.c
87 /* easy access to can_frame payload */
88 static inline u64 GET_U64(const struct can_frame *cp)
90 return *(u64 *)cp->data;
94 struct list_head list;
98 unsigned long frames_abs, frames_filtered;
99 struct timeval ival1, ival2;
100 struct timer_list timer, thrtimer;
101 struct timeval rx_stamp;
102 unsigned long j_ival1, j_ival2, j_lastmsg;
107 struct can_frame *frames;
108 struct can_frame *last_frames;
109 struct can_frame sframe;
110 struct can_frame last_sframe;
112 struct net_device *rx_reg_dev;
115 static struct proc_dir_entry *proc_dir;
118 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
125 struct notifier_block notifier;
126 struct list_head rx_ops;
127 struct list_head tx_ops;
128 unsigned long dropped_usr_msgs;
129 struct proc_dir_entry *bcm_proc_read;
130 char procname [9]; /* pointer printed in ASCII with \0 */
133 static inline struct bcm_sock *bcm_sk(const struct sock *sk)
135 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
136 return (struct bcm_sock *)sk;
138 return (struct bcm_sock *)sk->sk_protinfo;
142 #define CFSIZ sizeof(struct can_frame)
143 #define OPSIZ sizeof(struct bcm_op)
144 #define MHSIZ sizeof(struct bcm_msg_head)
147 * rounded_tv2jif - calculate jiffies from timeval including optional up
148 * @tv: pointer to timeval
151 * Unlike timeval_to_jiffies() provided in include/linux/jiffies.h, this
152 * function is intentionally more relaxed on precise timer ticks to get
153 * exact one jiffy for requested 1000us on a 1000HZ machine.
154 * This code is to be removed when upgrading to kernel hrtimer.
157 * calculated jiffies (max: ULONG_MAX)
159 static unsigned long rounded_tv2jif(const struct timeval *tv)
161 unsigned long sec = tv->tv_sec;
162 unsigned long usec = tv->tv_usec;
165 if (sec > ULONG_MAX / HZ)
168 /* round up to get at least the requested time */
169 usec += 1000000 / HZ - 1;
171 jif = usec / (1000000 / HZ);
173 if (sec * HZ > ULONG_MAX - jif)
176 return jif + sec * HZ;
182 static char *bcm_proc_getifname(int ifindex)
184 struct net_device *dev;
189 /* no usage counting */
190 dev = __dev_get_by_index(&init_net, ifindex);
197 static int bcm_read_proc(char *page, char **start, off_t off,
198 int count, int *eof, void *data)
201 struct sock *sk = (struct sock *)data;
202 struct bcm_sock *bo = bcm_sk(sk);
205 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p",
207 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk);
208 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo);
209 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu",
210 bo->dropped_usr_msgs);
211 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s",
212 bcm_proc_getifname(bo->ifindex));
213 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n");
215 list_for_each_entry(op, &bo->rx_ops, list) {
217 unsigned long reduction;
219 /* print only active entries & prevent division by zero */
223 len += snprintf(page + len, PAGE_SIZE - len,
225 op->can_id, bcm_proc_getifname(op->ifindex));
226 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ",
228 (op->flags & RX_CHECK_DLC)?'d':' ');
230 len += snprintf(page + len, PAGE_SIZE - len,
231 "timeo=%ld ", op->j_ival1);
234 len += snprintf(page + len, PAGE_SIZE - len,
235 "thr=%ld ", op->j_ival2);
237 len += snprintf(page + len, PAGE_SIZE - len,
238 "# recv %ld (%ld) => reduction: ",
239 op->frames_filtered, op->frames_abs);
241 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs;
243 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n",
244 (reduction == 100)?"near ":"", reduction);
246 if (len > PAGE_SIZE - 200) {
247 /* mark output cut off */
248 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
253 list_for_each_entry(op, &bo->tx_ops, list) {
255 len += snprintf(page + len, PAGE_SIZE - len,
256 "tx_op: %03X %s [%d] ",
257 op->can_id, bcm_proc_getifname(op->ifindex),
261 len += snprintf(page + len, PAGE_SIZE - len, "t1=%ld ",
265 len += snprintf(page + len, PAGE_SIZE - len, "t2=%ld ",
268 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n",
271 if (len > PAGE_SIZE - 100) {
272 /* mark output cut off */
273 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n");
278 len += snprintf(page + len, PAGE_SIZE - len, "\n");
285 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
286 * of the given bcm tx op
288 static void bcm_can_tx(struct bcm_op *op)
291 struct net_device *dev;
292 struct can_frame *cf = &op->frames[op->currframe];
294 /* no target device? => exit */
298 dev = dev_get_by_index(&init_net, op->ifindex);
300 /* RFC: should this bcm_op remove itself here? */
304 skb = alloc_skb(CFSIZ, gfp_any());
308 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ);
310 /* send with loopback */
315 /* update statistics */
319 /* reached last frame? */
320 if (op->currframe >= op->nframes)
327 * bcm_send_to_user - send a BCM message to the userspace
328 * (consisting of bcm_msg_head + x CAN frames)
330 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head,
331 struct can_frame *frames, int has_timestamp)
334 struct can_frame *firstframe;
335 struct sockaddr_can *addr;
336 struct sock *sk = op->sk;
337 int datalen = head->nframes * CFSIZ;
340 skb = alloc_skb(sizeof(*head) + datalen, gfp_any());
344 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head));
347 /* can_frames starting here */
348 firstframe = (struct can_frame *)skb->tail;
350 memcpy(skb_put(skb, datalen), frames, datalen);
353 * the BCM uses the can_dlc-element of the can_frame
354 * structure for internal purposes. This is only
355 * relevant for updates that are generated by the
356 * BCM, where nframes is 1
358 if (head->nframes == 1)
359 firstframe->can_dlc &= BCM_CAN_DLC_MASK;
363 /* restore rx timestamp */
364 skb_set_timestamp(skb, &op->rx_stamp);
368 * Put the datagram to the queue so that bcm_recvmsg() can
369 * get it from there. We need to pass the interface index to
370 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
371 * containing the interface index.
374 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
375 addr = (struct sockaddr_can *)skb->cb;
376 memset(addr, 0, sizeof(*addr));
377 addr->can_family = AF_CAN;
378 addr->can_ifindex = op->rx_ifindex;
380 err = sock_queue_rcv_skb(sk, skb);
382 struct bcm_sock *bo = bcm_sk(sk);
385 /* don't care about overflows in this statistic */
386 bo->dropped_usr_msgs++;
391 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
393 static void bcm_tx_timeout_handler(unsigned long data)
395 struct bcm_op *op = (struct bcm_op *)data;
397 if (op->j_ival1 && (op->count > 0)) {
400 if (!op->count && (op->flags & TX_COUNTEVT)) {
401 struct bcm_msg_head msg_head;
403 /* create notification to user */
404 msg_head.opcode = TX_EXPIRED;
405 msg_head.flags = op->flags;
406 msg_head.count = op->count;
407 msg_head.ival1 = op->ival1;
408 msg_head.ival2 = op->ival2;
409 msg_head.can_id = op->can_id;
410 msg_head.nframes = 0;
412 bcm_send_to_user(op, &msg_head, NULL, 0);
416 if (op->j_ival1 && (op->count > 0)) {
418 /* send (next) frame */
420 mod_timer(&op->timer, jiffies + op->j_ival1);
425 /* send (next) frame */
427 mod_timer(&op->timer, jiffies + op->j_ival2);
435 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
437 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
439 struct bcm_msg_head head;
441 op->j_lastmsg = jiffies;
443 /* update statistics */
444 op->frames_filtered++;
446 /* prevent statistics overflow */
447 if (op->frames_filtered > ULONG_MAX/100)
448 op->frames_filtered = op->frames_abs = 0;
450 head.opcode = RX_CHANGED;
451 head.flags = op->flags;
452 head.count = op->count;
453 head.ival1 = op->ival1;
454 head.ival2 = op->ival2;
455 head.can_id = op->can_id;
458 bcm_send_to_user(op, &head, data, 1);
462 * bcm_rx_update_and_send - process a detected relevant receive content change
463 * 1. update the last received data
464 * 2. send a notification to the user (if possible)
466 static void bcm_rx_update_and_send(struct bcm_op *op,
467 struct can_frame *lastdata,
468 struct can_frame *rxdata)
470 unsigned long nexttx = op->j_lastmsg + op->j_ival2;
472 memcpy(lastdata, rxdata, CFSIZ);
475 lastdata->can_dlc |= RX_RECV;
477 /* throttle bcm_rx_changed ? */
478 if ((op->thrtimer.expires) ||
479 ((op->j_ival2) && (nexttx > jiffies))) {
480 /* we are already waiting OR we have to start waiting */
482 /* mark as 'throttled' */
483 lastdata->can_dlc |= RX_THR;
485 if (!(op->thrtimer.expires)) {
486 /* start the timer only the first time */
487 mod_timer(&op->thrtimer, nexttx);
491 /* send RX_CHANGED to the user immediately */
492 bcm_rx_changed(op, rxdata);
497 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
498 * received data stored in op->last_frames[]
500 static void bcm_rx_cmp_to_index(struct bcm_op *op, int index,
501 struct can_frame *rxdata)
504 * no one uses the MSBs of can_dlc for comparation,
505 * so we use it here to detect the first time of reception
508 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
509 /* received data for the first time => send update to user */
510 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
514 /* do a real check in can_frame data section */
516 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
517 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
518 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
522 if (op->flags & RX_CHECK_DLC) {
523 /* do a real check in can_frame dlc */
524 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
526 bcm_rx_update_and_send(op, &op->last_frames[index],
534 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
536 static void bcm_rx_starttimer(struct bcm_op *op)
538 if (op->flags & RX_NO_AUTOTIMER)
542 mod_timer(&op->timer, jiffies + op->j_ival1);
546 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
548 static void bcm_rx_timeout_handler(unsigned long data)
550 struct bcm_op *op = (struct bcm_op *)data;
551 struct bcm_msg_head msg_head;
553 msg_head.opcode = RX_TIMEOUT;
554 msg_head.flags = op->flags;
555 msg_head.count = op->count;
556 msg_head.ival1 = op->ival1;
557 msg_head.ival2 = op->ival2;
558 msg_head.can_id = op->can_id;
559 msg_head.nframes = 0;
561 bcm_send_to_user(op, &msg_head, NULL, 0);
563 /* no restart of the timer is done here! */
565 /* if user wants to be informed, when cyclic CAN-Messages come back */
566 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
567 /* clear received can_frames to indicate 'nothing received' */
568 memset(op->last_frames, 0, op->nframes * CFSIZ);
573 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
575 static int bcm_rx_thr_flush(struct bcm_op *op)
579 if (op->nframes > 1) {
582 /* for MUX filter we start at index 1 */
583 for (i = 1; i < op->nframes; i++) {
584 if ((op->last_frames) &&
585 (op->last_frames[i].can_dlc & RX_THR)) {
586 op->last_frames[i].can_dlc &= ~RX_THR;
587 bcm_rx_changed(op, &op->last_frames[i]);
593 /* for RX_FILTER_ID and simple filter */
594 if (op->last_frames && (op->last_frames[0].can_dlc & RX_THR)) {
595 op->last_frames[0].can_dlc &= ~RX_THR;
596 bcm_rx_changed(op, &op->last_frames[0]);
605 * bcm_rx_thr_handler - the time for blocked content updates is over now:
606 * Check for throttled data and send it to the userspace
608 static void bcm_rx_thr_handler(unsigned long data)
610 struct bcm_op *op = (struct bcm_op *)data;
612 if (bcm_rx_thr_flush(op))
613 mod_timer(&op->thrtimer, jiffies + op->j_ival2);
615 /* mark disabled / consumed timer */
616 op->thrtimer.expires = 0;
621 * bcm_rx_handler - handle a CAN frame receiption
623 static void bcm_rx_handler(struct sk_buff *skb, void *data)
625 struct bcm_op *op = (struct bcm_op *)data;
626 struct can_frame rxframe;
629 /* disable timeout */
630 del_timer(&op->timer);
632 if (skb->len == sizeof(rxframe)) {
633 memcpy(&rxframe, skb->data, sizeof(rxframe));
634 /* save rx timestamp */
635 skb_get_timestamp(skb, &op->rx_stamp);
636 /* save originator for recvfrom() */
637 op->rx_ifindex = skb->dev->ifindex;
638 /* update statistics */
647 if (op->can_id != rxframe.can_id)
650 if (op->flags & RX_RTR_FRAME) {
651 /* send reply for RTR-request (placed in op->frames[0]) */
656 if (op->flags & RX_FILTER_ID) {
657 /* the easiest case */
658 bcm_rx_update_and_send(op, &op->last_frames[0], &rxframe);
659 bcm_rx_starttimer(op);
663 if (op->nframes == 1) {
664 /* simple compare with index 0 */
665 bcm_rx_cmp_to_index(op, 0, &rxframe);
666 bcm_rx_starttimer(op);
670 if (op->nframes > 1) {
674 * find the first multiplex mask that fits.
675 * Remark: The MUX-mask is stored in index 0
678 for (i = 1; i < op->nframes; i++) {
679 if ((GET_U64(&op->frames[0]) & GET_U64(&rxframe)) ==
680 (GET_U64(&op->frames[0]) &
681 GET_U64(&op->frames[i]))) {
682 bcm_rx_cmp_to_index(op, i, &rxframe);
686 bcm_rx_starttimer(op);
691 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
693 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
698 list_for_each_entry(op, ops, list) {
699 if ((op->can_id == can_id) && (op->ifindex == ifindex))
706 static void bcm_remove_op(struct bcm_op *op)
708 del_timer(&op->timer);
709 del_timer(&op->thrtimer);
711 if ((op->frames) && (op->frames != &op->sframe))
714 if ((op->last_frames) && (op->last_frames != &op->last_sframe))
715 kfree(op->last_frames);
722 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
724 if (op->rx_reg_dev == dev) {
725 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
728 /* mark as removed subscription */
729 op->rx_reg_dev = NULL;
731 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
732 "mismatch %p %p\n", op->rx_reg_dev, dev);
736 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
738 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
740 struct bcm_op *op, *n;
742 list_for_each_entry_safe(op, n, ops, list) {
743 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
746 * Don't care if we're bound or not (due to netdev
747 * problems) can_rx_unregister() is always a save
752 * Only remove subscriptions that had not
753 * been removed due to NETDEV_UNREGISTER
756 if (op->rx_reg_dev) {
757 struct net_device *dev;
759 dev = dev_get_by_index(&init_net,
762 bcm_rx_unreg(dev, op);
767 can_rx_unregister(NULL, op->can_id,
777 return 0; /* not found */
781 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
783 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
785 struct bcm_op *op, *n;
787 list_for_each_entry_safe(op, n, ops, list) {
788 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
795 return 0; /* not found */
799 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
801 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
804 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
809 /* put current values into msg_head */
810 msg_head->flags = op->flags;
811 msg_head->count = op->count;
812 msg_head->ival1 = op->ival1;
813 msg_head->ival2 = op->ival2;
814 msg_head->nframes = op->nframes;
816 bcm_send_to_user(op, msg_head, op->frames, 0);
822 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
824 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
825 int ifindex, struct sock *sk)
827 struct bcm_sock *bo = bcm_sk(sk);
831 /* we need a real device to send frames */
835 /* we need at least one can_frame */
836 if (msg_head->nframes < 1)
839 /* check the given can_id */
840 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
843 /* update existing BCM operation */
846 * Do we need more space for the can_frames than currently
847 * allocated? -> This is a _really_ unusual use-case and
848 * therefore (complexity / locking) it is not supported.
850 if (msg_head->nframes > op->nframes)
853 /* update can_frames content */
854 for (i = 0; i < msg_head->nframes; i++) {
855 err = memcpy_fromiovec((u8 *)&op->frames[i],
856 msg->msg_iov, CFSIZ);
858 if (op->frames[i].can_dlc > 8)
864 if (msg_head->flags & TX_CP_CAN_ID) {
865 /* copy can_id into frame */
866 op->frames[i].can_id = msg_head->can_id;
871 /* insert new BCM operation for the given can_id */
873 op = kzalloc(OPSIZ, GFP_KERNEL);
877 op->can_id = msg_head->can_id;
879 /* create array for can_frames and copy the data */
880 if (msg_head->nframes > 1) {
881 op->frames = kmalloc(msg_head->nframes * CFSIZ,
888 op->frames = &op->sframe;
890 for (i = 0; i < msg_head->nframes; i++) {
891 err = memcpy_fromiovec((u8 *)&op->frames[i],
892 msg->msg_iov, CFSIZ);
894 if (op->frames[i].can_dlc > 8)
898 if (op->frames != &op->sframe)
904 if (msg_head->flags & TX_CP_CAN_ID) {
905 /* copy can_id into frame */
906 op->frames[i].can_id = msg_head->can_id;
910 /* tx_ops never compare with previous received messages */
911 op->last_frames = NULL;
913 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
915 op->ifindex = ifindex;
917 /* initialize uninitialized (kzalloc) structure */
918 setup_timer(&op->timer, bcm_tx_timeout_handler,
921 /* currently unused in tx_ops */
922 init_timer(&op->thrtimer);
924 /* add this bcm_op to the list of the tx_ops */
925 list_add(&op->list, &bo->tx_ops);
927 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
929 if (op->nframes != msg_head->nframes) {
930 op->nframes = msg_head->nframes;
931 /* start multiple frame transmission with index 0 */
937 op->flags = msg_head->flags;
939 if (op->flags & TX_RESET_MULTI_IDX) {
940 /* start multiple frame transmission with index 0 */
944 if (op->flags & SETTIMER) {
945 /* set timer values */
946 op->count = msg_head->count;
947 op->ival1 = msg_head->ival1;
948 op->ival2 = msg_head->ival2;
949 op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
950 op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
952 /* disable an active timer due to zero values? */
953 if (!op->j_ival1 && !op->j_ival2)
954 del_timer(&op->timer);
957 if ((op->flags & STARTTIMER) &&
958 ((op->j_ival1 && op->count) || op->j_ival2)) {
960 /* spec: send can_frame when starting timer */
961 op->flags |= TX_ANNOUNCE;
963 if (op->j_ival1 && (op->count > 0)) {
964 /* op->count-- is done in bcm_tx_timeout_handler */
965 mod_timer(&op->timer, jiffies + op->j_ival1);
967 mod_timer(&op->timer, jiffies + op->j_ival2);
970 if (op->flags & TX_ANNOUNCE)
973 return msg_head->nframes * CFSIZ + MHSIZ;
977 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
979 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
980 int ifindex, struct sock *sk)
982 struct bcm_sock *bo = bcm_sk(sk);
987 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
988 /* be robust against wrong usage ... */
989 msg_head->flags |= RX_FILTER_ID;
990 /* ignore trailing garbage */
991 msg_head->nframes = 0;
994 if ((msg_head->flags & RX_RTR_FRAME) &&
995 ((msg_head->nframes != 1) ||
996 (!(msg_head->can_id & CAN_RTR_FLAG))))
999 /* check the given can_id */
1000 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
1002 /* update existing BCM operation */
1005 * Do we need more space for the can_frames than currently
1006 * allocated? -> This is a _really_ unusual use-case and
1007 * therefore (complexity / locking) it is not supported.
1009 if (msg_head->nframes > op->nframes)
1012 if (msg_head->nframes) {
1013 /* update can_frames content */
1014 err = memcpy_fromiovec((u8 *)op->frames,
1016 msg_head->nframes * CFSIZ);
1020 /* clear last_frames to indicate 'nothing received' */
1021 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
1024 op->nframes = msg_head->nframes;
1026 /* Only an update -> do not call can_rx_register() */
1030 /* insert new BCM operation for the given can_id */
1031 op = kzalloc(OPSIZ, GFP_KERNEL);
1035 op->can_id = msg_head->can_id;
1036 op->nframes = msg_head->nframes;
1038 if (msg_head->nframes > 1) {
1039 /* create array for can_frames and copy the data */
1040 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1047 /* create and init array for received can_frames */
1048 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1050 if (!op->last_frames) {
1057 op->frames = &op->sframe;
1058 op->last_frames = &op->last_sframe;
1061 if (msg_head->nframes) {
1062 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1063 msg_head->nframes * CFSIZ);
1065 if (op->frames != &op->sframe)
1067 if (op->last_frames != &op->last_sframe)
1068 kfree(op->last_frames);
1074 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1076 op->ifindex = ifindex;
1078 /* initialize uninitialized (kzalloc) structure */
1079 setup_timer(&op->timer, bcm_rx_timeout_handler,
1082 /* init throttle timer for RX_CHANGED */
1083 setup_timer(&op->thrtimer, bcm_rx_thr_handler,
1086 /* mark disabled timer */
1087 op->thrtimer.expires = 0;
1089 /* add this bcm_op to the list of the rx_ops */
1090 list_add(&op->list, &bo->rx_ops);
1092 /* call can_rx_register() */
1095 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1098 op->flags = msg_head->flags;
1100 if (op->flags & RX_RTR_FRAME) {
1102 /* no timers in RTR-mode */
1103 del_timer(&op->thrtimer);
1104 del_timer(&op->timer);
1107 * funny feature in RX(!)_SETUP only for RTR-mode:
1108 * copy can_id into frame BUT without RTR-flag to
1109 * prevent a full-load-loopback-test ... ;-]
1111 if ((op->flags & TX_CP_CAN_ID) ||
1112 (op->frames[0].can_id == op->can_id))
1113 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1116 if (op->flags & SETTIMER) {
1118 /* set timer value */
1119 op->ival1 = msg_head->ival1;
1120 op->ival2 = msg_head->ival2;
1121 op->j_ival1 = rounded_tv2jif(&msg_head->ival1);
1122 op->j_ival2 = rounded_tv2jif(&msg_head->ival2);
1124 /* disable an active timer due to zero value? */
1126 del_timer(&op->timer);
1129 * In any case cancel the throttle timer, flush
1130 * potentially blocked msgs and reset throttle handling
1132 del_timer(&op->thrtimer);
1133 bcm_rx_thr_flush(op);
1134 op->thrtimer.expires = 0;
1137 if ((op->flags & STARTTIMER) && op->j_ival1)
1138 mod_timer(&op->timer, jiffies + op->j_ival1);
1141 /* now we can register for can_ids, if we added a new bcm_op */
1142 if (do_rx_register) {
1144 struct net_device *dev;
1146 dev = dev_get_by_index(&init_net, ifindex);
1148 err = can_rx_register(dev, op->can_id,
1149 REGMASK(op->can_id),
1153 op->rx_reg_dev = dev;
1158 err = can_rx_register(NULL, op->can_id,
1159 REGMASK(op->can_id),
1160 bcm_rx_handler, op, "bcm");
1162 /* this bcm rx op is broken -> remove it */
1163 list_del(&op->list);
1169 return msg_head->nframes * CFSIZ + MHSIZ;
1173 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1175 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1177 struct sk_buff *skb;
1178 struct net_device *dev;
1181 /* we need a real device to send frames */
1185 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1190 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1196 dev = dev_get_by_index(&init_net, ifindex);
1204 err = can_send(skb, 1); /* send with loopback */
1210 return CFSIZ + MHSIZ;
1214 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1216 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1217 struct msghdr *msg, size_t size)
1219 struct sock *sk = sock->sk;
1220 struct bcm_sock *bo = bcm_sk(sk);
1221 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1222 struct bcm_msg_head msg_head;
1223 int ret; /* read bytes or error codes as return value */
1228 /* check for valid message length from userspace */
1229 if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
1232 /* check for alternative ifindex for this bcm_op */
1234 if (!ifindex && msg->msg_name) {
1235 /* no bound device as default => check msg_name */
1236 struct sockaddr_can *addr =
1237 (struct sockaddr_can *)msg->msg_name;
1239 if (addr->can_family != AF_CAN)
1242 /* ifindex from sendto() */
1243 ifindex = addr->can_ifindex;
1246 struct net_device *dev;
1248 dev = dev_get_by_index(&init_net, ifindex);
1252 if (dev->type != ARPHRD_CAN) {
1261 /* read message head information */
1263 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1269 switch (msg_head.opcode) {
1272 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1276 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1280 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1287 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1294 /* reuse msg_head for the reply to TX_READ */
1295 msg_head.opcode = TX_STATUS;
1296 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1300 /* reuse msg_head for the reply to RX_READ */
1301 msg_head.opcode = RX_STATUS;
1302 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1306 /* we need exactly one can_frame behind the msg head */
1307 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
1310 ret = bcm_tx_send(msg, ifindex, sk);
1324 * notification handler for netdevice status changes
1326 static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1329 struct net_device *dev = (struct net_device *)data;
1330 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1331 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
1332 struct sock *sk = &bo->sk;
1334 struct sock *sk = bo->sk;
1337 int notify_enodev = 0;
1339 if (dev->type != ARPHRD_CAN)
1344 case NETDEV_UNREGISTER:
1347 /* remove device specific receive entries */
1348 list_for_each_entry(op, &bo->rx_ops, list)
1349 if (op->rx_reg_dev == dev)
1350 bcm_rx_unreg(dev, op);
1352 /* remove device reference, if this is our bound device */
1353 if (bo->bound && bo->ifindex == dev->ifindex) {
1361 if (notify_enodev) {
1362 sk->sk_err = ENODEV;
1363 if (!sock_flag(sk, SOCK_DEAD))
1364 sk->sk_error_report(sk);
1369 if (bo->bound && bo->ifindex == dev->ifindex) {
1370 sk->sk_err = ENETDOWN;
1371 if (!sock_flag(sk, SOCK_DEAD))
1372 sk->sk_error_report(sk);
1380 * initial settings for all BCM sockets to be set at socket creation time
1382 static int bcm_init(struct sock *sk)
1384 struct bcm_sock *bo = bcm_sk(sk);
1386 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
1391 bo->dropped_usr_msgs = 0;
1392 bo->bcm_proc_read = NULL;
1394 INIT_LIST_HEAD(&bo->tx_ops);
1395 INIT_LIST_HEAD(&bo->rx_ops);
1398 bo->notifier.notifier_call = bcm_notifier;
1400 register_netdevice_notifier(&bo->notifier);
1406 * standard socket functions
1408 static int bcm_release(struct socket *sock)
1410 struct sock *sk = sock->sk;
1411 struct bcm_sock *bo = bcm_sk(sk);
1412 struct bcm_op *op, *next;
1414 /* remove bcm_ops, timer, rx_unregister(), etc. */
1416 unregister_netdevice_notifier(&bo->notifier);
1420 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1423 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1425 * Don't care if we're bound or not (due to netdev problems)
1426 * can_rx_unregister() is always a save thing to do here.
1430 * Only remove subscriptions that had not
1431 * been removed due to NETDEV_UNREGISTER
1434 if (op->rx_reg_dev) {
1435 struct net_device *dev;
1437 dev = dev_get_by_index(&init_net, op->ifindex);
1439 bcm_rx_unreg(dev, op);
1444 can_rx_unregister(NULL, op->can_id,
1445 REGMASK(op->can_id),
1446 bcm_rx_handler, op);
1451 /* remove procfs entry */
1452 if (proc_dir && bo->bcm_proc_read)
1453 remove_proc_entry(bo->procname, proc_dir);
1455 /* remove device reference */
1467 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1470 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1471 struct sock *sk = sock->sk;
1472 struct bcm_sock *bo = bcm_sk(sk);
1477 /* bind a device to this socket */
1478 if (addr->can_ifindex) {
1479 struct net_device *dev;
1481 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1485 if (dev->type != ARPHRD_CAN) {
1490 bo->ifindex = dev->ifindex;
1494 /* no interface reference for ifindex = 0 ('any' CAN device) */
1501 /* unique socket address as filename */
1502 sprintf(bo->procname, "%p", sock);
1503 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
1511 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1512 struct msghdr *msg, size_t size, int flags)
1514 struct sock *sk = sock->sk;
1515 struct sk_buff *skb;
1520 noblock = flags & MSG_DONTWAIT;
1521 flags &= ~MSG_DONTWAIT;
1522 skb = skb_recv_datagram(sk, flags, noblock, &error);
1526 if (skb->len < size)
1529 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1531 skb_free_datagram(sk, skb);
1535 sock_recv_timestamp(msg, sk, skb);
1537 if (msg->msg_name) {
1538 msg->msg_namelen = sizeof(struct sockaddr_can);
1539 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1542 skb_free_datagram(sk, skb);
1547 static struct proto_ops bcm_ops __read_mostly = {
1549 .release = bcm_release,
1550 .bind = sock_no_bind,
1551 .connect = bcm_connect,
1552 .socketpair = sock_no_socketpair,
1553 .accept = sock_no_accept,
1554 .getname = sock_no_getname,
1555 .poll = datagram_poll,
1556 .ioctl = NULL, /* use can_ioctl() from af_can.c */
1557 .listen = sock_no_listen,
1558 .shutdown = sock_no_shutdown,
1559 .setsockopt = sock_no_setsockopt,
1560 .getsockopt = sock_no_getsockopt,
1561 .sendmsg = bcm_sendmsg,
1562 .recvmsg = bcm_recvmsg,
1563 .mmap = sock_no_mmap,
1564 .sendpage = sock_no_sendpage,
1567 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
1568 static struct proto bcm_proto __read_mostly = {
1570 .owner = THIS_MODULE,
1571 .obj_size = sizeof(struct bcm_sock),
1575 static struct can_proto bcm_can_proto __read_mostly = {
1577 .protocol = CAN_BCM,
1583 static struct can_proto bcm_can_proto __read_mostly = {
1585 .protocol = CAN_BCM,
1588 .owner = THIS_MODULE,
1589 .obj_size = sizeof(struct bcm_sock),
1594 static int __init bcm_module_init(void)
1600 err = can_proto_register(&bcm_can_proto);
1602 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1606 /* create /proc/net/can-bcm directory */
1607 proc_dir = proc_mkdir("can-bcm", proc_net);
1610 proc_dir->owner = THIS_MODULE;
1615 static void __exit bcm_module_exit(void)
1617 can_proto_unregister(&bcm_can_proto);
1620 proc_net_remove("can-bcm");
1623 module_init(bcm_module_init);
1624 module_exit(bcm_module_exit);