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
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11 * notice, this list of conditions and the following disclaimer.
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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_start_timer(struct bcm_op *op)
465 if (op->kt_ival1.tv64 && op->count)
466 hrtimer_start(&op->timer,
467 ktime_add(ktime_get(), op->kt_ival1),
469 else if (op->kt_ival2.tv64)
470 hrtimer_start(&op->timer,
471 ktime_add(ktime_get(), op->kt_ival2),
475 static void bcm_tx_timeout_tsklet(unsigned long data)
477 struct bcm_op *op = (struct bcm_op *)data;
478 struct bcm_msg_head msg_head;
480 if (op->kt_ival1.tv64 && (op->count > 0)) {
483 if (!op->count && (op->flags & TX_COUNTEVT)) {
485 /* create notification to user */
486 msg_head.opcode = TX_EXPIRED;
487 msg_head.flags = op->flags;
488 msg_head.count = op->count;
489 msg_head.ival1 = op->ival1;
490 msg_head.ival2 = op->ival2;
491 msg_head.can_id = op->can_id;
492 msg_head.nframes = 0;
494 bcm_send_to_user(op, &msg_head, NULL, 0);
498 } else if (op->kt_ival2.tv64)
501 bcm_tx_start_timer(op);
505 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
507 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer)
509 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
511 tasklet_schedule(&op->tsklet);
513 return HRTIMER_NORESTART;
517 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
519 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data)
521 struct bcm_msg_head head;
523 /* update statistics */
524 op->frames_filtered++;
526 /* prevent statistics overflow */
527 if (op->frames_filtered > ULONG_MAX/100)
528 op->frames_filtered = op->frames_abs = 0;
530 /* this element is not throttled anymore */
531 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV);
533 head.opcode = RX_CHANGED;
534 head.flags = op->flags;
535 head.count = op->count;
536 head.ival1 = op->ival1;
537 head.ival2 = op->ival2;
538 head.can_id = op->can_id;
541 bcm_send_to_user(op, &head, data, 1);
544 #if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,25)
545 /* is part of linux/hrtimer.h since 2.6.26 */
546 static inline int hrtimer_callback_running(struct hrtimer *timer)
548 return timer->state & HRTIMER_STATE_CALLBACK;
551 #if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,22)
552 static inline s64 ktime_us_delta(const ktime_t later, const ktime_t earlier)
554 return ktime_to_us(ktime_sub(later, earlier));
558 * bcm_rx_update_and_send - process a detected relevant receive content change
559 * 1. update the last received data
560 * 2. send a notification to the user (if possible)
562 static void bcm_rx_update_and_send(struct bcm_op *op,
563 struct can_frame *lastdata,
564 const struct can_frame *rxdata)
566 memcpy(lastdata, rxdata, CFSIZ);
568 /* mark as used and throttled by default */
569 lastdata->can_dlc |= (RX_RECV|RX_THR);
571 /* throtteling mode inactive ? */
572 if (!op->kt_ival2.tv64) {
573 /* send RX_CHANGED to the user immediately */
574 bcm_rx_changed(op, lastdata);
578 /* with active throttling timer we are just done here */
579 if (hrtimer_active(&op->thrtimer))
582 /* first receiption with enabled throttling mode */
583 if (!op->kt_lastmsg.tv64)
584 goto rx_changed_settime;
586 /* got a second frame inside a potential throttle period? */
587 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) <
588 ktime_to_us(op->kt_ival2)) {
589 /* do not send the saved data - only start throttle timer */
590 hrtimer_start(&op->thrtimer,
591 ktime_add(op->kt_lastmsg, op->kt_ival2),
596 /* the gap was that big, that throttling was not needed here */
598 bcm_rx_changed(op, lastdata);
599 op->kt_lastmsg = ktime_get();
603 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
604 * received data stored in op->last_frames[]
606 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index,
607 const struct can_frame *rxdata)
610 * no one uses the MSBs of can_dlc for comparation,
611 * so we use it here to detect the first time of reception
614 if (!(op->last_frames[index].can_dlc & RX_RECV)) {
615 /* received data for the first time => send update to user */
616 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
620 /* do a real check in can_frame data section */
622 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) !=
623 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) {
624 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata);
628 if (op->flags & RX_CHECK_DLC) {
629 /* do a real check in can_frame dlc */
630 if (rxdata->can_dlc != (op->last_frames[index].can_dlc &
632 bcm_rx_update_and_send(op, &op->last_frames[index],
640 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
642 static void bcm_rx_starttimer(struct bcm_op *op)
644 if (op->flags & RX_NO_AUTOTIMER)
647 if (op->kt_ival1.tv64)
648 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL);
651 static void bcm_rx_timeout_tsklet(unsigned long data)
653 struct bcm_op *op = (struct bcm_op *)data;
654 struct bcm_msg_head msg_head;
656 /* create notification to user */
657 msg_head.opcode = RX_TIMEOUT;
658 msg_head.flags = op->flags;
659 msg_head.count = op->count;
660 msg_head.ival1 = op->ival1;
661 msg_head.ival2 = op->ival2;
662 msg_head.can_id = op->can_id;
663 msg_head.nframes = 0;
665 bcm_send_to_user(op, &msg_head, NULL, 0);
669 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
671 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer)
673 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer);
675 /* schedule before NET_RX_SOFTIRQ */
676 tasklet_hi_schedule(&op->tsklet);
678 /* no restart of the timer is done here! */
680 /* if user wants to be informed, when cyclic CAN-Messages come back */
681 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) {
682 /* clear received can_frames to indicate 'nothing received' */
683 memset(op->last_frames, 0, op->nframes * CFSIZ);
686 return HRTIMER_NORESTART;
690 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
692 static inline int bcm_rx_do_flush(struct bcm_op *op, int update,
695 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) {
697 bcm_rx_changed(op, &op->last_frames[index]);
704 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
706 * update == 0 : just check if throttled data is available (any irq context)
707 * update == 1 : check and send throttled data to userspace (soft_irq context)
709 static int bcm_rx_thr_flush(struct bcm_op *op, int update)
713 if (op->nframes > 1) {
716 /* for MUX filter we start at index 1 */
717 for (i = 1; i < op->nframes; i++)
718 updated += bcm_rx_do_flush(op, update, i);
721 /* for RX_FILTER_ID and simple filter */
722 updated += bcm_rx_do_flush(op, update, 0);
728 static void bcm_rx_thr_tsklet(unsigned long data)
730 struct bcm_op *op = (struct bcm_op *)data;
732 /* push the changed data to the userspace */
733 bcm_rx_thr_flush(op, 1);
737 * bcm_rx_thr_handler - the time for blocked content updates is over now:
738 * Check for throttled data and send it to the userspace
740 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer)
742 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer);
744 tasklet_schedule(&op->thrtsklet);
746 if (bcm_rx_thr_flush(op, 0)) {
747 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2);
748 return HRTIMER_RESTART;
750 /* rearm throttle handling */
751 op->kt_lastmsg = ktime_set(0, 0);
752 return HRTIMER_NORESTART;
757 * bcm_rx_handler - handle a CAN frame receiption
759 static void bcm_rx_handler(struct sk_buff *skb, void *data)
761 struct bcm_op *op = (struct bcm_op *)data;
762 const struct can_frame *rxframe = (struct can_frame *)skb->data;
765 /* disable timeout */
766 hrtimer_cancel(&op->timer);
768 if (op->can_id != rxframe->can_id)
771 /* save rx timestamp */
772 op->rx_stamp = skb->tstamp;
773 /* save originator for recvfrom() */
774 op->rx_ifindex = skb->dev->ifindex;
775 /* update statistics */
778 if (op->flags & RX_RTR_FRAME) {
779 /* send reply for RTR-request (placed in op->frames[0]) */
784 if (op->flags & RX_FILTER_ID) {
785 /* the easiest case */
786 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe);
790 if (op->nframes == 1) {
791 /* simple compare with index 0 */
792 bcm_rx_cmp_to_index(op, 0, rxframe);
796 if (op->nframes > 1) {
800 * find the first multiplex mask that fits.
801 * Remark: The MUX-mask is stored in index 0
804 for (i = 1; i < op->nframes; i++) {
805 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) ==
806 (GET_U64(&op->frames[0]) &
807 GET_U64(&op->frames[i]))) {
808 bcm_rx_cmp_to_index(op, i, rxframe);
815 bcm_rx_starttimer(op);
819 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
821 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id,
826 list_for_each_entry(op, ops, list) {
827 if ((op->can_id == can_id) && (op->ifindex == ifindex))
834 static void bcm_remove_op(struct bcm_op *op)
836 hrtimer_cancel(&op->timer);
837 hrtimer_cancel(&op->thrtimer);
840 tasklet_kill(&op->tsklet);
842 if (op->thrtsklet.func)
843 tasklet_kill(&op->thrtsklet);
845 if ((op->frames) && (op->frames != &op->sframe))
848 if ((op->last_frames) && (op->last_frames != &op->last_sframe))
849 kfree(op->last_frames);
856 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op)
858 if (op->rx_reg_dev == dev) {
859 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id),
862 /* mark as removed subscription */
863 op->rx_reg_dev = NULL;
865 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device "
866 "mismatch %p %p\n", op->rx_reg_dev, dev);
870 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
872 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex)
874 struct bcm_op *op, *n;
876 list_for_each_entry_safe(op, n, ops, list) {
877 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
880 * Don't care if we're bound or not (due to netdev
881 * problems) can_rx_unregister() is always a save
886 * Only remove subscriptions that had not
887 * been removed due to NETDEV_UNREGISTER
890 if (op->rx_reg_dev) {
891 struct net_device *dev;
893 dev = dev_get_by_index(&init_net,
896 bcm_rx_unreg(dev, op);
901 can_rx_unregister(NULL, op->can_id,
911 return 0; /* not found */
915 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
917 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex)
919 struct bcm_op *op, *n;
921 list_for_each_entry_safe(op, n, ops, list) {
922 if ((op->can_id == can_id) && (op->ifindex == ifindex)) {
929 return 0; /* not found */
933 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
935 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head,
938 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex);
943 /* put current values into msg_head */
944 msg_head->flags = op->flags;
945 msg_head->count = op->count;
946 msg_head->ival1 = op->ival1;
947 msg_head->ival2 = op->ival2;
948 msg_head->nframes = op->nframes;
950 bcm_send_to_user(op, msg_head, op->frames, 0);
956 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
958 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
959 int ifindex, struct sock *sk)
961 struct bcm_sock *bo = bcm_sk(sk);
966 /* we need a real device to send frames */
970 /* check nframes boundaries - we need at least one can_frame */
971 if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES)
974 /* check the given can_id */
975 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex);
978 /* update existing BCM operation */
981 * Do we need more space for the can_frames than currently
982 * allocated? -> This is a _really_ unusual use-case and
983 * therefore (complexity / locking) it is not supported.
985 if (msg_head->nframes > op->nframes)
988 /* update can_frames content */
989 for (i = 0; i < msg_head->nframes; i++) {
990 err = memcpy_fromiovec((u8 *)&op->frames[i],
991 msg->msg_iov, CFSIZ);
993 if (op->frames[i].can_dlc > 8)
999 if (msg_head->flags & TX_CP_CAN_ID) {
1000 /* copy can_id into frame */
1001 op->frames[i].can_id = msg_head->can_id;
1006 /* insert new BCM operation for the given can_id */
1008 op = kzalloc(OPSIZ, GFP_KERNEL);
1012 op->can_id = msg_head->can_id;
1014 /* create array for can_frames and copy the data */
1015 if (msg_head->nframes > 1) {
1016 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1023 op->frames = &op->sframe;
1025 for (i = 0; i < msg_head->nframes; i++) {
1026 err = memcpy_fromiovec((u8 *)&op->frames[i],
1027 msg->msg_iov, CFSIZ);
1029 if (op->frames[i].can_dlc > 8)
1033 if (op->frames != &op->sframe)
1039 if (msg_head->flags & TX_CP_CAN_ID) {
1040 /* copy can_id into frame */
1041 op->frames[i].can_id = msg_head->can_id;
1045 /* tx_ops never compare with previous received messages */
1046 op->last_frames = NULL;
1048 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1050 op->ifindex = ifindex;
1052 /* initialize uninitialized (kzalloc) structure */
1053 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1054 op->timer.function = bcm_tx_timeout_handler;
1056 /* initialize tasklet for tx countevent notification */
1057 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet,
1058 (unsigned long) op);
1060 /* currently unused in tx_ops */
1061 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1063 /* add this bcm_op to the list of the tx_ops */
1064 list_add(&op->list, &bo->tx_ops);
1066 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
1068 if (op->nframes != msg_head->nframes) {
1069 op->nframes = msg_head->nframes;
1070 /* start multiple frame transmission with index 0 */
1076 op->flags = msg_head->flags;
1078 if (op->flags & TX_RESET_MULTI_IDX) {
1079 /* start multiple frame transmission with index 0 */
1083 if (op->flags & SETTIMER) {
1084 /* set timer values */
1085 op->count = msg_head->count;
1086 op->ival1 = msg_head->ival1;
1087 op->ival2 = msg_head->ival2;
1088 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1089 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1091 /* disable an active timer due to zero values? */
1092 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64)
1093 hrtimer_cancel(&op->timer);
1096 if (op->flags & STARTTIMER) {
1097 hrtimer_cancel(&op->timer);
1098 /* spec: send can_frame when starting timer */
1099 op->flags |= TX_ANNOUNCE;
1102 if (op->flags & TX_ANNOUNCE) {
1108 if (op->flags & STARTTIMER)
1109 bcm_tx_start_timer(op);
1111 return msg_head->nframes * CFSIZ + MHSIZ;
1115 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
1117 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg,
1118 int ifindex, struct sock *sk)
1120 struct bcm_sock *bo = bcm_sk(sk);
1125 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) {
1126 /* be robust against wrong usage ... */
1127 msg_head->flags |= RX_FILTER_ID;
1128 /* ignore trailing garbage */
1129 msg_head->nframes = 0;
1132 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1133 if (msg_head->nframes > MAX_NFRAMES + 1)
1136 if ((msg_head->flags & RX_RTR_FRAME) &&
1137 ((msg_head->nframes != 1) ||
1138 (!(msg_head->can_id & CAN_RTR_FLAG))))
1141 /* check the given can_id */
1142 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex);
1144 /* update existing BCM operation */
1147 * Do we need more space for the can_frames than currently
1148 * allocated? -> This is a _really_ unusual use-case and
1149 * therefore (complexity / locking) it is not supported.
1151 if (msg_head->nframes > op->nframes)
1154 if (msg_head->nframes) {
1155 /* update can_frames content */
1156 err = memcpy_fromiovec((u8 *)op->frames,
1158 msg_head->nframes * CFSIZ);
1162 /* clear last_frames to indicate 'nothing received' */
1163 memset(op->last_frames, 0, msg_head->nframes * CFSIZ);
1166 op->nframes = msg_head->nframes;
1168 /* Only an update -> do not call can_rx_register() */
1172 /* insert new BCM operation for the given can_id */
1173 op = kzalloc(OPSIZ, GFP_KERNEL);
1177 op->can_id = msg_head->can_id;
1178 op->nframes = msg_head->nframes;
1180 if (msg_head->nframes > 1) {
1181 /* create array for can_frames and copy the data */
1182 op->frames = kmalloc(msg_head->nframes * CFSIZ,
1189 /* create and init array for received can_frames */
1190 op->last_frames = kzalloc(msg_head->nframes * CFSIZ,
1192 if (!op->last_frames) {
1199 op->frames = &op->sframe;
1200 op->last_frames = &op->last_sframe;
1203 if (msg_head->nframes) {
1204 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov,
1205 msg_head->nframes * CFSIZ);
1207 if (op->frames != &op->sframe)
1209 if (op->last_frames != &op->last_sframe)
1210 kfree(op->last_frames);
1216 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1218 op->ifindex = ifindex;
1220 /* initialize uninitialized (kzalloc) structure */
1221 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1222 op->timer.function = bcm_rx_timeout_handler;
1224 /* initialize tasklet for rx timeout notification */
1225 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet,
1226 (unsigned long) op);
1228 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1229 op->thrtimer.function = bcm_rx_thr_handler;
1231 /* initialize tasklet for rx throttle handling */
1232 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet,
1233 (unsigned long) op);
1235 /* add this bcm_op to the list of the rx_ops */
1236 list_add(&op->list, &bo->rx_ops);
1238 /* call can_rx_register() */
1241 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1244 op->flags = msg_head->flags;
1246 if (op->flags & RX_RTR_FRAME) {
1248 /* no timers in RTR-mode */
1249 hrtimer_cancel(&op->thrtimer);
1250 hrtimer_cancel(&op->timer);
1253 * funny feature in RX(!)_SETUP only for RTR-mode:
1254 * copy can_id into frame BUT without RTR-flag to
1255 * prevent a full-load-loopback-test ... ;-]
1257 if ((op->flags & TX_CP_CAN_ID) ||
1258 (op->frames[0].can_id == op->can_id))
1259 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG;
1262 if (op->flags & SETTIMER) {
1264 /* set timer value */
1265 op->ival1 = msg_head->ival1;
1266 op->ival2 = msg_head->ival2;
1267 op->kt_ival1 = timeval_to_ktime(msg_head->ival1);
1268 op->kt_ival2 = timeval_to_ktime(msg_head->ival2);
1270 /* disable an active timer due to zero value? */
1271 if (!op->kt_ival1.tv64)
1272 hrtimer_cancel(&op->timer);
1275 * In any case cancel the throttle timer, flush
1276 * potentially blocked msgs and reset throttle handling
1278 op->kt_lastmsg = ktime_set(0, 0);
1279 hrtimer_cancel(&op->thrtimer);
1280 bcm_rx_thr_flush(op, 1);
1283 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64)
1284 hrtimer_start(&op->timer, op->kt_ival1,
1288 /* now we can register for can_ids, if we added a new bcm_op */
1289 if (do_rx_register) {
1291 struct net_device *dev;
1293 dev = dev_get_by_index(&init_net, ifindex);
1295 err = can_rx_register(dev, op->can_id,
1296 REGMASK(op->can_id),
1300 op->rx_reg_dev = dev;
1305 err = can_rx_register(NULL, op->can_id,
1306 REGMASK(op->can_id),
1307 bcm_rx_handler, op, "bcm");
1309 /* this bcm rx op is broken -> remove it */
1310 list_del(&op->list);
1316 return msg_head->nframes * CFSIZ + MHSIZ;
1320 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1322 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk)
1324 struct sk_buff *skb;
1325 struct net_device *dev;
1328 /* we need a real device to send frames */
1332 skb = alloc_skb(CFSIZ, GFP_KERNEL);
1337 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ);
1343 dev = dev_get_by_index(&init_net, ifindex);
1351 err = can_send(skb, 1); /* send with loopback */
1357 return CFSIZ + MHSIZ;
1361 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1363 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock,
1364 struct msghdr *msg, size_t size)
1366 struct sock *sk = sock->sk;
1367 struct bcm_sock *bo = bcm_sk(sk);
1368 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */
1369 struct bcm_msg_head msg_head;
1370 int ret; /* read bytes or error codes as return value */
1375 /* check for valid message length from userspace */
1376 if (size < MHSIZ || (size - MHSIZ) % CFSIZ)
1379 /* check for alternative ifindex for this bcm_op */
1381 if (!ifindex && msg->msg_name) {
1382 /* no bound device as default => check msg_name */
1383 struct sockaddr_can *addr =
1384 (struct sockaddr_can *)msg->msg_name;
1386 if (msg->msg_namelen < sizeof(*addr))
1389 if (addr->can_family != AF_CAN)
1392 /* ifindex from sendto() */
1393 ifindex = addr->can_ifindex;
1396 struct net_device *dev;
1398 dev = dev_get_by_index(&init_net, ifindex);
1402 if (dev->type != ARPHRD_CAN) {
1411 /* read message head information */
1413 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ);
1419 switch (msg_head.opcode) {
1422 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk);
1426 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk);
1430 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex))
1437 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex))
1444 /* reuse msg_head for the reply to TX_READ */
1445 msg_head.opcode = TX_STATUS;
1446 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex);
1450 /* reuse msg_head for the reply to RX_READ */
1451 msg_head.opcode = RX_STATUS;
1452 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex);
1456 /* we need exactly one can_frame behind the msg head */
1457 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ))
1460 ret = bcm_tx_send(msg, ifindex, sk);
1474 * notification handler for netdevice status changes
1476 static int bcm_notifier(struct notifier_block *nb, unsigned long msg,
1479 struct net_device *dev = (struct net_device *)data;
1480 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier);
1481 struct sock *sk = &bo->sk;
1483 int notify_enodev = 0;
1485 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
1486 if (!net_eq(dev_net(dev), &init_net))
1488 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1489 if (dev->nd_net != &init_net)
1493 if (dev->type != ARPHRD_CAN)
1498 case NETDEV_UNREGISTER:
1501 /* remove device specific receive entries */
1502 list_for_each_entry(op, &bo->rx_ops, list)
1503 if (op->rx_reg_dev == dev)
1504 bcm_rx_unreg(dev, op);
1506 /* remove device reference, if this is our bound device */
1507 if (bo->bound && bo->ifindex == dev->ifindex) {
1515 if (notify_enodev) {
1516 sk->sk_err = ENODEV;
1517 if (!sock_flag(sk, SOCK_DEAD))
1518 sk->sk_error_report(sk);
1523 if (bo->bound && bo->ifindex == dev->ifindex) {
1524 sk->sk_err = ENETDOWN;
1525 if (!sock_flag(sk, SOCK_DEAD))
1526 sk->sk_error_report(sk);
1534 * initial settings for all BCM sockets to be set at socket creation time
1536 static int bcm_init(struct sock *sk)
1538 struct bcm_sock *bo = bcm_sk(sk);
1542 bo->dropped_usr_msgs = 0;
1543 bo->bcm_proc_read = NULL;
1545 INIT_LIST_HEAD(&bo->tx_ops);
1546 INIT_LIST_HEAD(&bo->rx_ops);
1549 bo->notifier.notifier_call = bcm_notifier;
1551 register_netdevice_notifier(&bo->notifier);
1557 * standard socket functions
1559 static int bcm_release(struct socket *sock)
1561 struct sock *sk = sock->sk;
1562 struct bcm_sock *bo;
1563 struct bcm_op *op, *next;
1570 /* remove bcm_ops, timer, rx_unregister(), etc. */
1572 unregister_netdevice_notifier(&bo->notifier);
1576 list_for_each_entry_safe(op, next, &bo->tx_ops, list)
1579 list_for_each_entry_safe(op, next, &bo->rx_ops, list) {
1581 * Don't care if we're bound or not (due to netdev problems)
1582 * can_rx_unregister() is always a save thing to do here.
1586 * Only remove subscriptions that had not
1587 * been removed due to NETDEV_UNREGISTER
1590 if (op->rx_reg_dev) {
1591 struct net_device *dev;
1593 dev = dev_get_by_index(&init_net, op->ifindex);
1595 bcm_rx_unreg(dev, op);
1600 can_rx_unregister(NULL, op->can_id,
1601 REGMASK(op->can_id),
1602 bcm_rx_handler, op);
1607 /* remove procfs entry */
1608 if (proc_dir && bo->bcm_proc_read)
1609 remove_proc_entry(bo->procname, proc_dir);
1611 /* remove device reference */
1626 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
1629 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
1630 struct sock *sk = sock->sk;
1631 struct bcm_sock *bo = bcm_sk(sk);
1633 if (len < sizeof(*addr))
1639 /* bind a device to this socket */
1640 if (addr->can_ifindex) {
1641 struct net_device *dev;
1643 dev = dev_get_by_index(&init_net, addr->can_ifindex);
1647 if (dev->type != ARPHRD_CAN) {
1652 bo->ifindex = dev->ifindex;
1656 /* no interface reference for ifindex = 0 ('any' CAN device) */
1663 /* unique socket address as filename */
1664 sprintf(bo->procname, "%lu", sock_i_ino(sk));
1665 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
1666 bo->bcm_proc_read = proc_create_data(bo->procname, 0644,
1668 &bcm_proc_fops, sk);
1670 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644,
1679 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock,
1680 struct msghdr *msg, size_t size, int flags)
1682 struct sock *sk = sock->sk;
1683 struct sk_buff *skb;
1688 noblock = flags & MSG_DONTWAIT;
1689 flags &= ~MSG_DONTWAIT;
1690 skb = skb_recv_datagram(sk, flags, noblock, &error);
1694 if (skb->len < size)
1697 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
1699 skb_free_datagram(sk, skb);
1703 sock_recv_timestamp(msg, sk, skb);
1705 if (msg->msg_name) {
1706 msg->msg_namelen = sizeof(struct sockaddr_can);
1707 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1710 skb_free_datagram(sk, skb);
1715 static const struct proto_ops bcm_ops = {
1717 .release = bcm_release,
1718 .bind = sock_no_bind,
1719 .connect = bcm_connect,
1720 .socketpair = sock_no_socketpair,
1721 .accept = sock_no_accept,
1722 .getname = sock_no_getname,
1723 .poll = datagram_poll,
1724 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
1725 .listen = sock_no_listen,
1726 .shutdown = sock_no_shutdown,
1727 .setsockopt = sock_no_setsockopt,
1728 .getsockopt = sock_no_getsockopt,
1729 .sendmsg = bcm_sendmsg,
1730 .recvmsg = bcm_recvmsg,
1731 .mmap = sock_no_mmap,
1732 .sendpage = sock_no_sendpage,
1735 static struct proto bcm_proto __read_mostly = {
1737 .owner = THIS_MODULE,
1738 .obj_size = sizeof(struct bcm_sock),
1742 static const struct can_proto bcm_can_proto = {
1744 .protocol = CAN_BCM,
1745 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,33)
1752 static int __init bcm_module_init(void)
1758 err = can_proto_register(&bcm_can_proto);
1760 printk(KERN_ERR "can: registration of bcm protocol failed\n");
1764 /* create /proc/net/can-bcm directory */
1765 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1766 proc_dir = proc_mkdir("can-bcm", init_net.proc_net);
1768 proc_dir = proc_mkdir("can-bcm", proc_net);
1771 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,30)
1773 proc_dir->owner = THIS_MODULE;
1779 static void __exit bcm_module_exit(void)
1781 can_proto_unregister(&bcm_can_proto);
1784 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
1785 proc_net_remove(&init_net, "can-bcm");
1787 proc_net_remove("can-bcm");
1791 module_init(bcm_module_init);
1792 module_exit(bcm_module_exit);