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
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
40 * Send feedback to <socketcan-users@lists.berlios.de>
44 #include <linux/module.h>
45 #include <linux/init.h>
46 #include <linux/hrtimer.h>
47 #include <linux/list.h>
48 #include <linux/proc_fs.h>
49 #include <linux/uio.h>
50 #include <linux/net.h>
51 #include <linux/netdevice.h>
52 #include <linux/socket.h>
53 #include <linux/if_arp.h>
54 #include <linux/skbuff.h>
55 #include <linux/can.h>
56 #include <linux/can/core.h>
57 #include <linux/can/bcm.h>
59 #include <net/net_namespace.h>
61 /* use of last_frames[index].can_dlc */
62 #define RX_RECV 0x40 /* received data for this element */
63 #define RX_THR 0x80 /* element not been sent due to throttle feature */
64 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
66 /* get best masking value for can_rx_register() for a given single can_id */
67 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
68 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
69 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
71 #define CAN_BCM_VERSION CAN_VERSION
72 static __initdata
const char banner
[] = KERN_INFO
73 "can: broadcast manager protocol (rev " CAN_BCM_VERSION
" t)\n";
75 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
76 MODULE_LICENSE("Dual BSD/GPL");
77 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
79 /* easy access to can_frame payload */
80 static inline u64
GET_U64(const struct can_frame
*cp
)
82 return *(u64
*)cp
->data
;
86 struct list_head list
;
90 unsigned long frames_abs
, frames_filtered
;
91 struct timeval ival1
, ival2
;
92 struct hrtimer timer
, thrtimer
;
93 struct tasklet_struct tsklet
, thrtsklet
;
94 ktime_t rx_stamp
, kt_ival1
, kt_ival2
, kt_lastmsg
;
99 struct can_frame
*frames
;
100 struct can_frame
*last_frames
;
101 struct can_frame sframe
;
102 struct can_frame last_sframe
;
104 struct net_device
*rx_reg_dev
;
107 static struct proc_dir_entry
*proc_dir
;
113 struct notifier_block notifier
;
114 struct list_head rx_ops
;
115 struct list_head tx_ops
;
116 unsigned long dropped_usr_msgs
;
117 struct proc_dir_entry
*bcm_proc_read
;
118 char procname
[9]; /* pointer printed in ASCII with \0 */
121 static inline struct bcm_sock
*bcm_sk(const struct sock
*sk
)
123 return (struct bcm_sock
*)sk
;
126 #define CFSIZ sizeof(struct can_frame)
127 #define OPSIZ sizeof(struct bcm_op)
128 #define MHSIZ sizeof(struct bcm_msg_head)
133 static char *bcm_proc_getifname(int ifindex
)
135 struct net_device
*dev
;
140 /* no usage counting */
141 dev
= __dev_get_by_index(&init_net
, ifindex
);
148 static int bcm_read_proc(char *page
, char **start
, off_t off
,
149 int count
, int *eof
, void *data
)
152 struct sock
*sk
= (struct sock
*)data
;
153 struct bcm_sock
*bo
= bcm_sk(sk
);
156 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, ">>> socket %p",
158 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, " / sk %p", sk
);
159 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, " / bo %p", bo
);
160 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, " / dropped %lu",
161 bo
->dropped_usr_msgs
);
162 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, " / bound %s",
163 bcm_proc_getifname(bo
->ifindex
));
164 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, " <<<\n");
166 list_for_each_entry(op
, &bo
->rx_ops
, list
) {
168 unsigned long reduction
;
170 /* print only active entries & prevent division by zero */
174 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
,
176 op
->can_id
, bcm_proc_getifname(op
->ifindex
));
177 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "[%d]%c ",
179 (op
->flags
& RX_CHECK_DLC
)?'d':' ');
180 if (op
->kt_ival1
.tv64
)
181 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
,
184 ktime_to_us(op
->kt_ival1
));
186 if (op
->kt_ival2
.tv64
)
187 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
,
190 ktime_to_us(op
->kt_ival2
));
192 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
,
193 "# recv %ld (%ld) => reduction: ",
194 op
->frames_filtered
, op
->frames_abs
);
196 reduction
= 100 - (op
->frames_filtered
* 100) / op
->frames_abs
;
198 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "%s%ld%%\n",
199 (reduction
== 100)?"near ":"", reduction
);
201 if (len
> PAGE_SIZE
- 200) {
202 /* mark output cut off */
203 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "(..)\n");
208 list_for_each_entry(op
, &bo
->tx_ops
, list
) {
210 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
,
211 "tx_op: %03X %s [%d] ",
212 op
->can_id
, bcm_proc_getifname(op
->ifindex
),
215 if (op
->kt_ival1
.tv64
)
216 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "t1=%lld ",
217 (long long) ktime_to_us(op
->kt_ival1
));
219 if (op
->kt_ival2
.tv64
)
220 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "t2=%lld ",
221 (long long) ktime_to_us(op
->kt_ival2
));
223 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "# sent %ld\n",
226 if (len
> PAGE_SIZE
- 100) {
227 /* mark output cut off */
228 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "(..)\n");
233 len
+= snprintf(page
+ len
, PAGE_SIZE
- len
, "\n");
240 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
241 * of the given bcm tx op
243 static void bcm_can_tx(struct bcm_op
*op
)
246 struct net_device
*dev
;
247 struct can_frame
*cf
= &op
->frames
[op
->currframe
];
249 /* no target device? => exit */
253 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
255 /* RFC: should this bcm_op remove itself here? */
259 skb
= alloc_skb(CFSIZ
, gfp_any());
263 memcpy(skb_put(skb
, CFSIZ
), cf
, CFSIZ
);
265 /* send with loopback */
270 /* update statistics */
274 /* reached last frame? */
275 if (op
->currframe
>= op
->nframes
)
282 * bcm_send_to_user - send a BCM message to the userspace
283 * (consisting of bcm_msg_head + x CAN frames)
285 static void bcm_send_to_user(struct bcm_op
*op
, struct bcm_msg_head
*head
,
286 struct can_frame
*frames
, int has_timestamp
)
289 struct can_frame
*firstframe
;
290 struct sockaddr_can
*addr
;
291 struct sock
*sk
= op
->sk
;
292 int datalen
= head
->nframes
* CFSIZ
;
295 skb
= alloc_skb(sizeof(*head
) + datalen
, gfp_any());
299 memcpy(skb_put(skb
, sizeof(*head
)), head
, sizeof(*head
));
302 /* can_frames starting here */
303 firstframe
= (struct can_frame
*)skb_tail_pointer(skb
);
305 memcpy(skb_put(skb
, datalen
), frames
, datalen
);
308 * the BCM uses the can_dlc-element of the can_frame
309 * structure for internal purposes. This is only
310 * relevant for updates that are generated by the
311 * BCM, where nframes is 1
313 if (head
->nframes
== 1)
314 firstframe
->can_dlc
&= BCM_CAN_DLC_MASK
;
318 /* restore rx timestamp */
319 skb
->tstamp
= op
->rx_stamp
;
323 * Put the datagram to the queue so that bcm_recvmsg() can
324 * get it from there. We need to pass the interface index to
325 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
326 * containing the interface index.
329 BUILD_BUG_ON(sizeof(skb
->cb
) < sizeof(struct sockaddr_can
));
330 addr
= (struct sockaddr_can
*)skb
->cb
;
331 memset(addr
, 0, sizeof(*addr
));
332 addr
->can_family
= AF_CAN
;
333 addr
->can_ifindex
= op
->rx_ifindex
;
335 err
= sock_queue_rcv_skb(sk
, skb
);
337 struct bcm_sock
*bo
= bcm_sk(sk
);
340 /* don't care about overflows in this statistic */
341 bo
->dropped_usr_msgs
++;
345 static void bcm_tx_timeout_tsklet(unsigned long data
)
347 struct bcm_op
*op
= (struct bcm_op
*)data
;
348 struct bcm_msg_head msg_head
;
350 /* create notification to user */
351 msg_head
.opcode
= TX_EXPIRED
;
352 msg_head
.flags
= op
->flags
;
353 msg_head
.count
= op
->count
;
354 msg_head
.ival1
= op
->ival1
;
355 msg_head
.ival2
= op
->ival2
;
356 msg_head
.can_id
= op
->can_id
;
357 msg_head
.nframes
= 0;
359 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
363 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions
365 static enum hrtimer_restart
bcm_tx_timeout_handler(struct hrtimer
*hrtimer
)
367 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
368 enum hrtimer_restart ret
= HRTIMER_NORESTART
;
370 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
373 if (!op
->count
&& (op
->flags
& TX_COUNTEVT
))
374 tasklet_schedule(&op
->tsklet
);
377 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
379 /* send (next) frame */
381 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival1
);
382 ret
= HRTIMER_RESTART
;
385 if (op
->kt_ival2
.tv64
) {
387 /* send (next) frame */
389 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
390 ret
= HRTIMER_RESTART
;
398 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
400 static void bcm_rx_changed(struct bcm_op
*op
, struct can_frame
*data
)
402 struct bcm_msg_head head
;
404 /* update statistics */
405 op
->frames_filtered
++;
407 /* prevent statistics overflow */
408 if (op
->frames_filtered
> ULONG_MAX
/100)
409 op
->frames_filtered
= op
->frames_abs
= 0;
411 /* this element is not throttled anymore */
412 data
->can_dlc
&= (BCM_CAN_DLC_MASK
|RX_RECV
);
414 head
.opcode
= RX_CHANGED
;
415 head
.flags
= op
->flags
;
416 head
.count
= op
->count
;
417 head
.ival1
= op
->ival1
;
418 head
.ival2
= op
->ival2
;
419 head
.can_id
= op
->can_id
;
422 bcm_send_to_user(op
, &head
, data
, 1);
426 * bcm_rx_update_and_send - process a detected relevant receive content change
427 * 1. update the last received data
428 * 2. send a notification to the user (if possible)
430 static void bcm_rx_update_and_send(struct bcm_op
*op
,
431 struct can_frame
*lastdata
,
432 const struct can_frame
*rxdata
)
434 memcpy(lastdata
, rxdata
, CFSIZ
);
436 /* mark as used and throttled by default */
437 lastdata
->can_dlc
|= (RX_RECV
|RX_THR
);
439 /* throtteling mode inactive ? */
440 if (!op
->kt_ival2
.tv64
) {
441 /* send RX_CHANGED to the user immediately */
442 bcm_rx_changed(op
, lastdata
);
446 /* with active throttling timer we are just done here */
447 if (hrtimer_active(&op
->thrtimer
))
450 /* first receiption with enabled throttling mode */
451 if (!op
->kt_lastmsg
.tv64
)
452 goto rx_changed_settime
;
454 /* got a second frame inside a potential throttle period? */
455 if (ktime_us_delta(ktime_get(), op
->kt_lastmsg
) <
456 ktime_to_us(op
->kt_ival2
)) {
457 /* do not send the saved data - only start throttle timer */
458 hrtimer_start(&op
->thrtimer
,
459 ktime_add(op
->kt_lastmsg
, op
->kt_ival2
),
464 /* the gap was that big, that throttling was not needed here */
466 bcm_rx_changed(op
, lastdata
);
467 op
->kt_lastmsg
= ktime_get();
471 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
472 * received data stored in op->last_frames[]
474 static void bcm_rx_cmp_to_index(struct bcm_op
*op
, int index
,
475 const struct can_frame
*rxdata
)
478 * no one uses the MSBs of can_dlc for comparation,
479 * so we use it here to detect the first time of reception
482 if (!(op
->last_frames
[index
].can_dlc
& RX_RECV
)) {
483 /* received data for the first time => send update to user */
484 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
488 /* do a real check in can_frame data section */
490 if ((GET_U64(&op
->frames
[index
]) & GET_U64(rxdata
)) !=
491 (GET_U64(&op
->frames
[index
]) & GET_U64(&op
->last_frames
[index
]))) {
492 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
496 if (op
->flags
& RX_CHECK_DLC
) {
497 /* do a real check in can_frame dlc */
498 if (rxdata
->can_dlc
!= (op
->last_frames
[index
].can_dlc
&
500 bcm_rx_update_and_send(op
, &op
->last_frames
[index
],
508 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
510 static void bcm_rx_starttimer(struct bcm_op
*op
)
512 if (op
->flags
& RX_NO_AUTOTIMER
)
515 if (op
->kt_ival1
.tv64
)
516 hrtimer_start(&op
->timer
, op
->kt_ival1
, HRTIMER_MODE_REL
);
519 static void bcm_rx_timeout_tsklet(unsigned long data
)
521 struct bcm_op
*op
= (struct bcm_op
*)data
;
522 struct bcm_msg_head msg_head
;
524 /* create notification to user */
525 msg_head
.opcode
= RX_TIMEOUT
;
526 msg_head
.flags
= op
->flags
;
527 msg_head
.count
= op
->count
;
528 msg_head
.ival1
= op
->ival1
;
529 msg_head
.ival2
= op
->ival2
;
530 msg_head
.can_id
= op
->can_id
;
531 msg_head
.nframes
= 0;
533 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
537 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
539 static enum hrtimer_restart
bcm_rx_timeout_handler(struct hrtimer
*hrtimer
)
541 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
543 /* schedule before NET_RX_SOFTIRQ */
544 tasklet_hi_schedule(&op
->tsklet
);
546 /* no restart of the timer is done here! */
548 /* if user wants to be informed, when cyclic CAN-Messages come back */
549 if ((op
->flags
& RX_ANNOUNCE_RESUME
) && op
->last_frames
) {
550 /* clear received can_frames to indicate 'nothing received' */
551 memset(op
->last_frames
, 0, op
->nframes
* CFSIZ
);
554 return HRTIMER_NORESTART
;
558 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
560 static inline int bcm_rx_do_flush(struct bcm_op
*op
, int update
, int index
)
562 if ((op
->last_frames
) && (op
->last_frames
[index
].can_dlc
& RX_THR
)) {
564 bcm_rx_changed(op
, &op
->last_frames
[index
]);
571 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
573 * update == 0 : just check if throttled data is available (any irq context)
574 * update == 1 : check and send throttled data to userspace (soft_irq context)
576 static int bcm_rx_thr_flush(struct bcm_op
*op
, int update
)
580 if (op
->nframes
> 1) {
583 /* for MUX filter we start at index 1 */
584 for (i
= 1; i
< op
->nframes
; i
++)
585 updated
+= bcm_rx_do_flush(op
, update
, i
);
588 /* for RX_FILTER_ID and simple filter */
589 updated
+= bcm_rx_do_flush(op
, update
, 0);
595 static void bcm_rx_thr_tsklet(unsigned long data
)
597 struct bcm_op
*op
= (struct bcm_op
*)data
;
599 /* push the changed data to the userspace */
600 bcm_rx_thr_flush(op
, 1);
604 * bcm_rx_thr_handler - the time for blocked content updates is over now:
605 * Check for throttled data and send it to the userspace
607 static enum hrtimer_restart
bcm_rx_thr_handler(struct hrtimer
*hrtimer
)
609 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, thrtimer
);
611 tasklet_schedule(&op
->thrtsklet
);
613 if (bcm_rx_thr_flush(op
, 0)) {
614 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
615 return HRTIMER_RESTART
;
617 /* rearm throttle handling */
618 op
->kt_lastmsg
= ktime_set(0, 0);
619 return HRTIMER_NORESTART
;
624 * bcm_rx_handler - handle a CAN frame receiption
626 static void bcm_rx_handler(struct sk_buff
*skb
, void *data
)
628 struct bcm_op
*op
= (struct bcm_op
*)data
;
629 const struct can_frame
*rxframe
= (struct can_frame
*)skb
->data
;
632 /* disable timeout */
633 hrtimer_cancel(&op
->timer
);
635 if (op
->can_id
!= rxframe
->can_id
)
638 /* save rx timestamp */
639 op
->rx_stamp
= skb
->tstamp
;
640 /* save originator for recvfrom() */
641 op
->rx_ifindex
= skb
->dev
->ifindex
;
642 /* update statistics */
645 if (op
->flags
& RX_RTR_FRAME
) {
646 /* send reply for RTR-request (placed in op->frames[0]) */
651 if (op
->flags
& RX_FILTER_ID
) {
652 /* the easiest case */
653 bcm_rx_update_and_send(op
, &op
->last_frames
[0], rxframe
);
654 goto rx_freeskb_starttimer
;
657 if (op
->nframes
== 1) {
658 /* simple compare with index 0 */
659 bcm_rx_cmp_to_index(op
, 0, rxframe
);
660 goto rx_freeskb_starttimer
;
663 if (op
->nframes
> 1) {
667 * find the first multiplex mask that fits.
668 * Remark: The MUX-mask is stored in index 0
671 for (i
= 1; i
< op
->nframes
; i
++) {
672 if ((GET_U64(&op
->frames
[0]) & GET_U64(rxframe
)) ==
673 (GET_U64(&op
->frames
[0]) &
674 GET_U64(&op
->frames
[i
]))) {
675 bcm_rx_cmp_to_index(op
, i
, rxframe
);
681 rx_freeskb_starttimer
:
682 bcm_rx_starttimer(op
);
688 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
690 static struct bcm_op
*bcm_find_op(struct list_head
*ops
, canid_t can_id
,
695 list_for_each_entry(op
, ops
, list
) {
696 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
))
703 static void bcm_remove_op(struct bcm_op
*op
)
705 hrtimer_cancel(&op
->timer
);
706 hrtimer_cancel(&op
->thrtimer
);
709 tasklet_kill(&op
->tsklet
);
711 if (op
->thrtsklet
.func
)
712 tasklet_kill(&op
->thrtsklet
);
714 if ((op
->frames
) && (op
->frames
!= &op
->sframe
))
717 if ((op
->last_frames
) && (op
->last_frames
!= &op
->last_sframe
))
718 kfree(op
->last_frames
);
725 static void bcm_rx_unreg(struct net_device
*dev
, struct bcm_op
*op
)
727 if (op
->rx_reg_dev
== dev
) {
728 can_rx_unregister(dev
, op
->can_id
, REGMASK(op
->can_id
),
731 /* mark as removed subscription */
732 op
->rx_reg_dev
= NULL
;
734 printk(KERN_ERR
"can-bcm: bcm_rx_unreg: registered device "
735 "mismatch %p %p\n", op
->rx_reg_dev
, dev
);
739 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
741 static int bcm_delete_rx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
743 struct bcm_op
*op
, *n
;
745 list_for_each_entry_safe(op
, n
, ops
, list
) {
746 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
749 * Don't care if we're bound or not (due to netdev
750 * problems) can_rx_unregister() is always a save
755 * Only remove subscriptions that had not
756 * been removed due to NETDEV_UNREGISTER
759 if (op
->rx_reg_dev
) {
760 struct net_device
*dev
;
762 dev
= dev_get_by_index(&init_net
,
765 bcm_rx_unreg(dev
, op
);
770 can_rx_unregister(NULL
, op
->can_id
,
780 return 0; /* not found */
784 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
786 static int bcm_delete_tx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
788 struct bcm_op
*op
, *n
;
790 list_for_each_entry_safe(op
, n
, ops
, list
) {
791 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
798 return 0; /* not found */
802 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
804 static int bcm_read_op(struct list_head
*ops
, struct bcm_msg_head
*msg_head
,
807 struct bcm_op
*op
= bcm_find_op(ops
, msg_head
->can_id
, ifindex
);
812 /* put current values into msg_head */
813 msg_head
->flags
= op
->flags
;
814 msg_head
->count
= op
->count
;
815 msg_head
->ival1
= op
->ival1
;
816 msg_head
->ival2
= op
->ival2
;
817 msg_head
->nframes
= op
->nframes
;
819 bcm_send_to_user(op
, msg_head
, op
->frames
, 0);
825 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
827 static int bcm_tx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
828 int ifindex
, struct sock
*sk
)
830 struct bcm_sock
*bo
= bcm_sk(sk
);
834 /* we need a real device to send frames */
838 /* we need at least one can_frame */
839 if (msg_head
->nframes
< 1)
842 /* check the given can_id */
843 op
= bcm_find_op(&bo
->tx_ops
, msg_head
->can_id
, ifindex
);
846 /* update existing BCM operation */
849 * Do we need more space for the can_frames than currently
850 * allocated? -> This is a _really_ unusual use-case and
851 * therefore (complexity / locking) it is not supported.
853 if (msg_head
->nframes
> op
->nframes
)
856 /* update can_frames content */
857 for (i
= 0; i
< msg_head
->nframes
; i
++) {
858 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
859 msg
->msg_iov
, CFSIZ
);
861 if (op
->frames
[i
].can_dlc
> 8)
867 if (msg_head
->flags
& TX_CP_CAN_ID
) {
868 /* copy can_id into frame */
869 op
->frames
[i
].can_id
= msg_head
->can_id
;
874 /* insert new BCM operation for the given can_id */
876 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
880 op
->can_id
= msg_head
->can_id
;
882 /* create array for can_frames and copy the data */
883 if (msg_head
->nframes
> 1) {
884 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
891 op
->frames
= &op
->sframe
;
893 for (i
= 0; i
< msg_head
->nframes
; i
++) {
894 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
895 msg
->msg_iov
, CFSIZ
);
897 if (op
->frames
[i
].can_dlc
> 8)
901 if (op
->frames
!= &op
->sframe
)
907 if (msg_head
->flags
& TX_CP_CAN_ID
) {
908 /* copy can_id into frame */
909 op
->frames
[i
].can_id
= msg_head
->can_id
;
913 /* tx_ops never compare with previous received messages */
914 op
->last_frames
= NULL
;
916 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
918 op
->ifindex
= ifindex
;
920 /* initialize uninitialized (kzalloc) structure */
921 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
922 op
->timer
.function
= bcm_tx_timeout_handler
;
924 /* initialize tasklet for tx countevent notification */
925 tasklet_init(&op
->tsklet
, bcm_tx_timeout_tsklet
,
928 /* currently unused in tx_ops */
929 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
931 /* add this bcm_op to the list of the tx_ops */
932 list_add(&op
->list
, &bo
->tx_ops
);
934 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
936 if (op
->nframes
!= msg_head
->nframes
) {
937 op
->nframes
= msg_head
->nframes
;
938 /* start multiple frame transmission with index 0 */
944 op
->flags
= msg_head
->flags
;
946 if (op
->flags
& TX_RESET_MULTI_IDX
) {
947 /* start multiple frame transmission with index 0 */
951 if (op
->flags
& SETTIMER
) {
952 /* set timer values */
953 op
->count
= msg_head
->count
;
954 op
->ival1
= msg_head
->ival1
;
955 op
->ival2
= msg_head
->ival2
;
956 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
957 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
959 /* disable an active timer due to zero values? */
960 if (!op
->kt_ival1
.tv64
&& !op
->kt_ival2
.tv64
)
961 hrtimer_cancel(&op
->timer
);
964 if ((op
->flags
& STARTTIMER
) &&
965 ((op
->kt_ival1
.tv64
&& op
->count
) || op
->kt_ival2
.tv64
)) {
967 /* spec: send can_frame when starting timer */
968 op
->flags
|= TX_ANNOUNCE
;
970 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
971 /* op->count-- is done in bcm_tx_timeout_handler */
972 hrtimer_start(&op
->timer
, op
->kt_ival1
,
975 hrtimer_start(&op
->timer
, op
->kt_ival2
,
979 if (op
->flags
& TX_ANNOUNCE
)
982 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
986 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
988 static int bcm_rx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
989 int ifindex
, struct sock
*sk
)
991 struct bcm_sock
*bo
= bcm_sk(sk
);
996 if ((msg_head
->flags
& RX_FILTER_ID
) || (!(msg_head
->nframes
))) {
997 /* be robust against wrong usage ... */
998 msg_head
->flags
|= RX_FILTER_ID
;
999 /* ignore trailing garbage */
1000 msg_head
->nframes
= 0;
1003 if ((msg_head
->flags
& RX_RTR_FRAME
) &&
1004 ((msg_head
->nframes
!= 1) ||
1005 (!(msg_head
->can_id
& CAN_RTR_FLAG
))))
1008 /* check the given can_id */
1009 op
= bcm_find_op(&bo
->rx_ops
, msg_head
->can_id
, ifindex
);
1011 /* update existing BCM operation */
1014 * Do we need more space for the can_frames than currently
1015 * allocated? -> This is a _really_ unusual use-case and
1016 * therefore (complexity / locking) it is not supported.
1018 if (msg_head
->nframes
> op
->nframes
)
1021 if (msg_head
->nframes
) {
1022 /* update can_frames content */
1023 err
= memcpy_fromiovec((u8
*)op
->frames
,
1025 msg_head
->nframes
* CFSIZ
);
1029 /* clear last_frames to indicate 'nothing received' */
1030 memset(op
->last_frames
, 0, msg_head
->nframes
* CFSIZ
);
1033 op
->nframes
= msg_head
->nframes
;
1035 /* Only an update -> do not call can_rx_register() */
1039 /* insert new BCM operation for the given can_id */
1040 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
1044 op
->can_id
= msg_head
->can_id
;
1045 op
->nframes
= msg_head
->nframes
;
1047 if (msg_head
->nframes
> 1) {
1048 /* create array for can_frames and copy the data */
1049 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
1056 /* create and init array for received can_frames */
1057 op
->last_frames
= kzalloc(msg_head
->nframes
* CFSIZ
,
1059 if (!op
->last_frames
) {
1066 op
->frames
= &op
->sframe
;
1067 op
->last_frames
= &op
->last_sframe
;
1070 if (msg_head
->nframes
) {
1071 err
= memcpy_fromiovec((u8
*)op
->frames
, msg
->msg_iov
,
1072 msg_head
->nframes
* CFSIZ
);
1074 if (op
->frames
!= &op
->sframe
)
1076 if (op
->last_frames
!= &op
->last_sframe
)
1077 kfree(op
->last_frames
);
1083 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1085 op
->ifindex
= ifindex
;
1087 /* initialize uninitialized (kzalloc) structure */
1088 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1089 op
->timer
.function
= bcm_rx_timeout_handler
;
1091 /* initialize tasklet for rx timeout notification */
1092 tasklet_init(&op
->tsklet
, bcm_rx_timeout_tsklet
,
1093 (unsigned long) op
);
1095 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1096 op
->thrtimer
.function
= bcm_rx_thr_handler
;
1098 /* initialize tasklet for rx throttle handling */
1099 tasklet_init(&op
->thrtsklet
, bcm_rx_thr_tsklet
,
1100 (unsigned long) op
);
1102 /* add this bcm_op to the list of the rx_ops */
1103 list_add(&op
->list
, &bo
->rx_ops
);
1105 /* call can_rx_register() */
1108 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1111 op
->flags
= msg_head
->flags
;
1113 if (op
->flags
& RX_RTR_FRAME
) {
1115 /* no timers in RTR-mode */
1116 hrtimer_cancel(&op
->thrtimer
);
1117 hrtimer_cancel(&op
->timer
);
1120 * funny feature in RX(!)_SETUP only for RTR-mode:
1121 * copy can_id into frame BUT without RTR-flag to
1122 * prevent a full-load-loopback-test ... ;-]
1124 if ((op
->flags
& TX_CP_CAN_ID
) ||
1125 (op
->frames
[0].can_id
== op
->can_id
))
1126 op
->frames
[0].can_id
= op
->can_id
& ~CAN_RTR_FLAG
;
1129 if (op
->flags
& SETTIMER
) {
1131 /* set timer value */
1132 op
->ival1
= msg_head
->ival1
;
1133 op
->ival2
= msg_head
->ival2
;
1134 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
1135 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
1137 /* disable an active timer due to zero value? */
1138 if (!op
->kt_ival1
.tv64
)
1139 hrtimer_cancel(&op
->timer
);
1142 * In any case cancel the throttle timer, flush
1143 * potentially blocked msgs and reset throttle handling
1145 op
->kt_lastmsg
= ktime_set(0, 0);
1146 hrtimer_cancel(&op
->thrtimer
);
1147 bcm_rx_thr_flush(op
, 1);
1150 if ((op
->flags
& STARTTIMER
) && op
->kt_ival1
.tv64
)
1151 hrtimer_start(&op
->timer
, op
->kt_ival1
,
1155 /* now we can register for can_ids, if we added a new bcm_op */
1156 if (do_rx_register
) {
1158 struct net_device
*dev
;
1160 dev
= dev_get_by_index(&init_net
, ifindex
);
1162 err
= can_rx_register(dev
, op
->can_id
,
1163 REGMASK(op
->can_id
),
1167 op
->rx_reg_dev
= dev
;
1172 err
= can_rx_register(NULL
, op
->can_id
,
1173 REGMASK(op
->can_id
),
1174 bcm_rx_handler
, op
, "bcm");
1176 /* this bcm rx op is broken -> remove it */
1177 list_del(&op
->list
);
1183 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
1187 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1189 static int bcm_tx_send(struct msghdr
*msg
, int ifindex
, struct sock
*sk
)
1191 struct sk_buff
*skb
;
1192 struct net_device
*dev
;
1195 /* we need a real device to send frames */
1199 skb
= alloc_skb(CFSIZ
, GFP_KERNEL
);
1204 err
= memcpy_fromiovec(skb_put(skb
, CFSIZ
), msg
->msg_iov
, CFSIZ
);
1210 dev
= dev_get_by_index(&init_net
, ifindex
);
1218 err
= can_send(skb
, 1); /* send with loopback */
1224 return CFSIZ
+ MHSIZ
;
1228 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1230 static int bcm_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1231 struct msghdr
*msg
, size_t size
)
1233 struct sock
*sk
= sock
->sk
;
1234 struct bcm_sock
*bo
= bcm_sk(sk
);
1235 int ifindex
= bo
->ifindex
; /* default ifindex for this bcm_op */
1236 struct bcm_msg_head msg_head
;
1237 int ret
; /* read bytes or error codes as return value */
1242 /* check for valid message length from userspace */
1243 if (size
< MHSIZ
|| (size
- MHSIZ
) % CFSIZ
)
1246 /* check for alternative ifindex for this bcm_op */
1248 if (!ifindex
&& msg
->msg_name
) {
1249 /* no bound device as default => check msg_name */
1250 struct sockaddr_can
*addr
=
1251 (struct sockaddr_can
*)msg
->msg_name
;
1253 if (addr
->can_family
!= AF_CAN
)
1256 /* ifindex from sendto() */
1257 ifindex
= addr
->can_ifindex
;
1260 struct net_device
*dev
;
1262 dev
= dev_get_by_index(&init_net
, ifindex
);
1266 if (dev
->type
!= ARPHRD_CAN
) {
1275 /* read message head information */
1277 ret
= memcpy_fromiovec((u8
*)&msg_head
, msg
->msg_iov
, MHSIZ
);
1283 switch (msg_head
.opcode
) {
1286 ret
= bcm_tx_setup(&msg_head
, msg
, ifindex
, sk
);
1290 ret
= bcm_rx_setup(&msg_head
, msg
, ifindex
, sk
);
1294 if (bcm_delete_tx_op(&bo
->tx_ops
, msg_head
.can_id
, ifindex
))
1301 if (bcm_delete_rx_op(&bo
->rx_ops
, msg_head
.can_id
, ifindex
))
1308 /* reuse msg_head for the reply to TX_READ */
1309 msg_head
.opcode
= TX_STATUS
;
1310 ret
= bcm_read_op(&bo
->tx_ops
, &msg_head
, ifindex
);
1314 /* reuse msg_head for the reply to RX_READ */
1315 msg_head
.opcode
= RX_STATUS
;
1316 ret
= bcm_read_op(&bo
->rx_ops
, &msg_head
, ifindex
);
1320 /* we need exactly one can_frame behind the msg head */
1321 if ((msg_head
.nframes
!= 1) || (size
!= CFSIZ
+ MHSIZ
))
1324 ret
= bcm_tx_send(msg
, ifindex
, sk
);
1338 * notification handler for netdevice status changes
1340 static int bcm_notifier(struct notifier_block
*nb
, unsigned long msg
,
1343 struct net_device
*dev
= (struct net_device
*)data
;
1344 struct bcm_sock
*bo
= container_of(nb
, struct bcm_sock
, notifier
);
1345 struct sock
*sk
= &bo
->sk
;
1347 int notify_enodev
= 0;
1349 if (!net_eq(dev_net(dev
), &init_net
))
1352 if (dev
->type
!= ARPHRD_CAN
)
1357 case NETDEV_UNREGISTER
:
1360 /* remove device specific receive entries */
1361 list_for_each_entry(op
, &bo
->rx_ops
, list
)
1362 if (op
->rx_reg_dev
== dev
)
1363 bcm_rx_unreg(dev
, op
);
1365 /* remove device reference, if this is our bound device */
1366 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1374 if (notify_enodev
) {
1375 sk
->sk_err
= ENODEV
;
1376 if (!sock_flag(sk
, SOCK_DEAD
))
1377 sk
->sk_error_report(sk
);
1382 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1383 sk
->sk_err
= ENETDOWN
;
1384 if (!sock_flag(sk
, SOCK_DEAD
))
1385 sk
->sk_error_report(sk
);
1393 * initial settings for all BCM sockets to be set at socket creation time
1395 static int bcm_init(struct sock
*sk
)
1397 struct bcm_sock
*bo
= bcm_sk(sk
);
1401 bo
->dropped_usr_msgs
= 0;
1402 bo
->bcm_proc_read
= NULL
;
1404 INIT_LIST_HEAD(&bo
->tx_ops
);
1405 INIT_LIST_HEAD(&bo
->rx_ops
);
1408 bo
->notifier
.notifier_call
= bcm_notifier
;
1410 register_netdevice_notifier(&bo
->notifier
);
1416 * standard socket functions
1418 static int bcm_release(struct socket
*sock
)
1420 struct sock
*sk
= sock
->sk
;
1421 struct bcm_sock
*bo
= bcm_sk(sk
);
1422 struct bcm_op
*op
, *next
;
1424 /* remove bcm_ops, timer, rx_unregister(), etc. */
1426 unregister_netdevice_notifier(&bo
->notifier
);
1430 list_for_each_entry_safe(op
, next
, &bo
->tx_ops
, list
)
1433 list_for_each_entry_safe(op
, next
, &bo
->rx_ops
, list
) {
1435 * Don't care if we're bound or not (due to netdev problems)
1436 * can_rx_unregister() is always a save thing to do here.
1440 * Only remove subscriptions that had not
1441 * been removed due to NETDEV_UNREGISTER
1444 if (op
->rx_reg_dev
) {
1445 struct net_device
*dev
;
1447 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
1449 bcm_rx_unreg(dev
, op
);
1454 can_rx_unregister(NULL
, op
->can_id
,
1455 REGMASK(op
->can_id
),
1456 bcm_rx_handler
, op
);
1461 /* remove procfs entry */
1462 if (proc_dir
&& bo
->bcm_proc_read
)
1463 remove_proc_entry(bo
->procname
, proc_dir
);
1465 /* remove device reference */
1477 static int bcm_connect(struct socket
*sock
, struct sockaddr
*uaddr
, int len
,
1480 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
1481 struct sock
*sk
= sock
->sk
;
1482 struct bcm_sock
*bo
= bcm_sk(sk
);
1487 /* bind a device to this socket */
1488 if (addr
->can_ifindex
) {
1489 struct net_device
*dev
;
1491 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
1495 if (dev
->type
!= ARPHRD_CAN
) {
1500 bo
->ifindex
= dev
->ifindex
;
1504 /* no interface reference for ifindex = 0 ('any' CAN device) */
1511 /* unique socket address as filename */
1512 sprintf(bo
->procname
, "%p", sock
);
1513 bo
->bcm_proc_read
= create_proc_read_entry(bo
->procname
, 0644,
1521 static int bcm_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1522 struct msghdr
*msg
, size_t size
, int flags
)
1524 struct sock
*sk
= sock
->sk
;
1525 struct sk_buff
*skb
;
1530 noblock
= flags
& MSG_DONTWAIT
;
1531 flags
&= ~MSG_DONTWAIT
;
1532 skb
= skb_recv_datagram(sk
, flags
, noblock
, &error
);
1536 if (skb
->len
< size
)
1539 err
= memcpy_toiovec(msg
->msg_iov
, skb
->data
, size
);
1541 skb_free_datagram(sk
, skb
);
1545 sock_recv_timestamp(msg
, sk
, skb
);
1547 if (msg
->msg_name
) {
1548 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
1549 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
1552 skb_free_datagram(sk
, skb
);
1557 static struct proto_ops bcm_ops __read_mostly
= {
1559 .release
= bcm_release
,
1560 .bind
= sock_no_bind
,
1561 .connect
= bcm_connect
,
1562 .socketpair
= sock_no_socketpair
,
1563 .accept
= sock_no_accept
,
1564 .getname
= sock_no_getname
,
1565 .poll
= datagram_poll
,
1566 .ioctl
= NULL
, /* use can_ioctl() from af_can.c */
1567 .listen
= sock_no_listen
,
1568 .shutdown
= sock_no_shutdown
,
1569 .setsockopt
= sock_no_setsockopt
,
1570 .getsockopt
= sock_no_getsockopt
,
1571 .sendmsg
= bcm_sendmsg
,
1572 .recvmsg
= bcm_recvmsg
,
1573 .mmap
= sock_no_mmap
,
1574 .sendpage
= sock_no_sendpage
,
1577 static struct proto bcm_proto __read_mostly
= {
1579 .owner
= THIS_MODULE
,
1580 .obj_size
= sizeof(struct bcm_sock
),
1584 static struct can_proto bcm_can_proto __read_mostly
= {
1586 .protocol
= CAN_BCM
,
1592 static int __init
bcm_module_init(void)
1598 err
= can_proto_register(&bcm_can_proto
);
1600 printk(KERN_ERR
"can: registration of bcm protocol failed\n");
1604 /* create /proc/net/can-bcm directory */
1605 proc_dir
= proc_mkdir("can-bcm", init_net
.proc_net
);
1608 proc_dir
->owner
= THIS_MODULE
;
1613 static void __exit
bcm_module_exit(void)
1615 can_proto_unregister(&bcm_can_proto
);
1618 proc_net_remove(&init_net
, "can-bcm");
1621 module_init(bcm_module_init
);
1622 module_exit(bcm_module_exit
);