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
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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/seq_file.h>
50 #include <linux/uio.h>
51 #include <linux/net.h>
52 #include <linux/netdevice.h>
53 #include <linux/socket.h>
54 #include <linux/if_arp.h>
55 #include <linux/skbuff.h>
56 #include <linux/can.h>
57 #include <linux/can/core.h>
58 #include <linux/can/bcm.h>
59 #include <linux/slab.h>
61 #include <net/net_namespace.h>
64 * To send multiple CAN frame content within TX_SETUP or to filter
65 * CAN messages with multiplex index within RX_SETUP, the number of
66 * different filters is limited to 256 due to the one byte index value.
68 #define MAX_NFRAMES 256
70 /* use of last_frames[index].can_dlc */
71 #define RX_RECV 0x40 /* received data for this element */
72 #define RX_THR 0x80 /* element not been sent due to throttle feature */
73 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
75 /* get best masking value for can_rx_register() for a given single can_id */
76 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
77 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
78 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
80 #define CAN_BCM_VERSION CAN_VERSION
81 static __initdata
const char banner
[] = KERN_INFO
82 "can: broadcast manager protocol (rev " CAN_BCM_VERSION
" t)\n";
84 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
85 MODULE_LICENSE("Dual BSD/GPL");
86 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
87 MODULE_ALIAS("can-proto-2");
89 /* easy access to can_frame payload */
90 static inline u64
GET_U64(const struct can_frame
*cp
)
92 return *(u64
*)cp
->data
;
96 struct list_head list
;
100 unsigned long frames_abs
, frames_filtered
;
101 struct timeval ival1
, ival2
;
102 struct hrtimer timer
, thrtimer
;
103 struct tasklet_struct tsklet
, thrtsklet
;
104 ktime_t rx_stamp
, kt_ival1
, kt_ival2
, kt_lastmsg
;
109 struct can_frame
*frames
;
110 struct can_frame
*last_frames
;
111 struct can_frame sframe
;
112 struct can_frame last_sframe
;
114 struct net_device
*rx_reg_dev
;
117 static struct proc_dir_entry
*proc_dir
;
123 struct notifier_block notifier
;
124 struct list_head rx_ops
;
125 struct list_head tx_ops
;
126 unsigned long dropped_usr_msgs
;
127 struct proc_dir_entry
*bcm_proc_read
;
128 char procname
[32]; /* inode number in decimal with \0 */
131 static inline struct bcm_sock
*bcm_sk(const struct sock
*sk
)
133 return (struct bcm_sock
*)sk
;
136 #define CFSIZ sizeof(struct can_frame)
137 #define OPSIZ sizeof(struct bcm_op)
138 #define MHSIZ sizeof(struct bcm_msg_head)
143 static char *bcm_proc_getifname(char *result
, int ifindex
)
145 struct net_device
*dev
;
151 dev
= dev_get_by_index_rcu(&init_net
, ifindex
);
153 strcpy(result
, dev
->name
);
155 strcpy(result
, "???");
161 static int bcm_proc_show(struct seq_file
*m
, void *v
)
163 char ifname
[IFNAMSIZ
];
164 struct sock
*sk
= (struct sock
*)m
->private;
165 struct bcm_sock
*bo
= bcm_sk(sk
);
168 seq_printf(m
, ">>> socket %pK", sk
->sk_socket
);
169 seq_printf(m
, " / sk %pK", sk
);
170 seq_printf(m
, " / bo %pK", bo
);
171 seq_printf(m
, " / dropped %lu", bo
->dropped_usr_msgs
);
172 seq_printf(m
, " / bound %s", bcm_proc_getifname(ifname
, bo
->ifindex
));
173 seq_printf(m
, " <<<\n");
175 list_for_each_entry(op
, &bo
->rx_ops
, list
) {
177 unsigned long reduction
;
179 /* print only active entries & prevent division by zero */
183 seq_printf(m
, "rx_op: %03X %-5s ",
184 op
->can_id
, bcm_proc_getifname(ifname
, op
->ifindex
));
185 seq_printf(m
, "[%u]%c ", op
->nframes
,
186 (op
->flags
& RX_CHECK_DLC
)?'d':' ');
187 if (op
->kt_ival1
.tv64
)
188 seq_printf(m
, "timeo=%lld ",
190 ktime_to_us(op
->kt_ival1
));
192 if (op
->kt_ival2
.tv64
)
193 seq_printf(m
, "thr=%lld ",
195 ktime_to_us(op
->kt_ival2
));
197 seq_printf(m
, "# recv %ld (%ld) => reduction: ",
198 op
->frames_filtered
, op
->frames_abs
);
200 reduction
= 100 - (op
->frames_filtered
* 100) / op
->frames_abs
;
202 seq_printf(m
, "%s%ld%%\n",
203 (reduction
== 100)?"near ":"", reduction
);
206 list_for_each_entry(op
, &bo
->tx_ops
, list
) {
208 seq_printf(m
, "tx_op: %03X %s [%u] ",
210 bcm_proc_getifname(ifname
, op
->ifindex
),
213 if (op
->kt_ival1
.tv64
)
214 seq_printf(m
, "t1=%lld ",
215 (long long) ktime_to_us(op
->kt_ival1
));
217 if (op
->kt_ival2
.tv64
)
218 seq_printf(m
, "t2=%lld ",
219 (long long) ktime_to_us(op
->kt_ival2
));
221 seq_printf(m
, "# sent %ld\n", op
->frames_abs
);
227 static int bcm_proc_open(struct inode
*inode
, struct file
*file
)
229 return single_open(file
, bcm_proc_show
, PDE(inode
)->data
);
232 static const struct file_operations bcm_proc_fops
= {
233 .owner
= THIS_MODULE
,
234 .open
= bcm_proc_open
,
237 .release
= single_release
,
241 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
242 * of the given bcm tx op
244 static void bcm_can_tx(struct bcm_op
*op
)
247 struct net_device
*dev
;
248 struct can_frame
*cf
= &op
->frames
[op
->currframe
];
250 /* no target device? => exit */
254 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
256 /* RFC: should this bcm_op remove itself here? */
260 skb
= alloc_skb(CFSIZ
, gfp_any());
264 memcpy(skb_put(skb
, CFSIZ
), cf
, CFSIZ
);
266 /* send with loopback */
271 /* update statistics */
275 /* reached last frame? */
276 if (op
->currframe
>= op
->nframes
)
283 * bcm_send_to_user - send a BCM message to the userspace
284 * (consisting of bcm_msg_head + x CAN frames)
286 static void bcm_send_to_user(struct bcm_op
*op
, struct bcm_msg_head
*head
,
287 struct can_frame
*frames
, int has_timestamp
)
290 struct can_frame
*firstframe
;
291 struct sockaddr_can
*addr
;
292 struct sock
*sk
= op
->sk
;
293 unsigned int datalen
= head
->nframes
* CFSIZ
;
296 skb
= alloc_skb(sizeof(*head
) + datalen
, gfp_any());
300 memcpy(skb_put(skb
, sizeof(*head
)), head
, sizeof(*head
));
303 /* can_frames starting here */
304 firstframe
= (struct can_frame
*)skb_tail_pointer(skb
);
306 memcpy(skb_put(skb
, datalen
), frames
, datalen
);
309 * the BCM uses the can_dlc-element of the can_frame
310 * structure for internal purposes. This is only
311 * relevant for updates that are generated by the
312 * BCM, where nframes is 1
314 if (head
->nframes
== 1)
315 firstframe
->can_dlc
&= BCM_CAN_DLC_MASK
;
319 /* restore rx timestamp */
320 skb
->tstamp
= op
->rx_stamp
;
324 * Put the datagram to the queue so that bcm_recvmsg() can
325 * get it from there. We need to pass the interface index to
326 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
327 * containing the interface index.
330 BUILD_BUG_ON(sizeof(skb
->cb
) < sizeof(struct sockaddr_can
));
331 addr
= (struct sockaddr_can
*)skb
->cb
;
332 memset(addr
, 0, sizeof(*addr
));
333 addr
->can_family
= AF_CAN
;
334 addr
->can_ifindex
= op
->rx_ifindex
;
336 err
= sock_queue_rcv_skb(sk
, skb
);
338 struct bcm_sock
*bo
= bcm_sk(sk
);
341 /* don't care about overflows in this statistic */
342 bo
->dropped_usr_msgs
++;
346 static void bcm_tx_timeout_tsklet(unsigned long data
)
348 struct bcm_op
*op
= (struct bcm_op
*)data
;
349 struct bcm_msg_head msg_head
;
351 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
354 if (!op
->count
&& (op
->flags
& TX_COUNTEVT
)) {
356 /* create notification to user */
357 msg_head
.opcode
= TX_EXPIRED
;
358 msg_head
.flags
= op
->flags
;
359 msg_head
.count
= op
->count
;
360 msg_head
.ival1
= op
->ival1
;
361 msg_head
.ival2
= op
->ival2
;
362 msg_head
.can_id
= op
->can_id
;
363 msg_head
.nframes
= 0;
365 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
368 /* send (next) frame */
370 hrtimer_start(&op
->timer
,
371 ktime_add(ktime_get(), op
->kt_ival1
),
375 if (op
->kt_ival2
.tv64
) {
377 /* send (next) frame */
379 hrtimer_start(&op
->timer
,
380 ktime_add(ktime_get(), op
->kt_ival2
),
387 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
389 static enum hrtimer_restart
bcm_tx_timeout_handler(struct hrtimer
*hrtimer
)
391 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
393 tasklet_schedule(&op
->tsklet
);
395 return HRTIMER_NORESTART
;
399 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
401 static void bcm_rx_changed(struct bcm_op
*op
, struct can_frame
*data
)
403 struct bcm_msg_head head
;
405 /* update statistics */
406 op
->frames_filtered
++;
408 /* prevent statistics overflow */
409 if (op
->frames_filtered
> ULONG_MAX
/100)
410 op
->frames_filtered
= op
->frames_abs
= 0;
412 /* this element is not throttled anymore */
413 data
->can_dlc
&= (BCM_CAN_DLC_MASK
|RX_RECV
);
415 head
.opcode
= RX_CHANGED
;
416 head
.flags
= op
->flags
;
417 head
.count
= op
->count
;
418 head
.ival1
= op
->ival1
;
419 head
.ival2
= op
->ival2
;
420 head
.can_id
= op
->can_id
;
423 bcm_send_to_user(op
, &head
, data
, 1);
427 * bcm_rx_update_and_send - process a detected relevant receive content change
428 * 1. update the last received data
429 * 2. send a notification to the user (if possible)
431 static void bcm_rx_update_and_send(struct bcm_op
*op
,
432 struct can_frame
*lastdata
,
433 const struct can_frame
*rxdata
)
435 memcpy(lastdata
, rxdata
, CFSIZ
);
437 /* mark as used and throttled by default */
438 lastdata
->can_dlc
|= (RX_RECV
|RX_THR
);
440 /* throtteling mode inactive ? */
441 if (!op
->kt_ival2
.tv64
) {
442 /* send RX_CHANGED to the user immediately */
443 bcm_rx_changed(op
, lastdata
);
447 /* with active throttling timer we are just done here */
448 if (hrtimer_active(&op
->thrtimer
))
451 /* first receiption with enabled throttling mode */
452 if (!op
->kt_lastmsg
.tv64
)
453 goto rx_changed_settime
;
455 /* got a second frame inside a potential throttle period? */
456 if (ktime_us_delta(ktime_get(), op
->kt_lastmsg
) <
457 ktime_to_us(op
->kt_ival2
)) {
458 /* do not send the saved data - only start throttle timer */
459 hrtimer_start(&op
->thrtimer
,
460 ktime_add(op
->kt_lastmsg
, op
->kt_ival2
),
465 /* the gap was that big, that throttling was not needed here */
467 bcm_rx_changed(op
, lastdata
);
468 op
->kt_lastmsg
= ktime_get();
472 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
473 * received data stored in op->last_frames[]
475 static void bcm_rx_cmp_to_index(struct bcm_op
*op
, unsigned int index
,
476 const struct can_frame
*rxdata
)
479 * no one uses the MSBs of can_dlc for comparation,
480 * so we use it here to detect the first time of reception
483 if (!(op
->last_frames
[index
].can_dlc
& RX_RECV
)) {
484 /* received data for the first time => send update to user */
485 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
489 /* do a real check in can_frame data section */
491 if ((GET_U64(&op
->frames
[index
]) & GET_U64(rxdata
)) !=
492 (GET_U64(&op
->frames
[index
]) & GET_U64(&op
->last_frames
[index
]))) {
493 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
497 if (op
->flags
& RX_CHECK_DLC
) {
498 /* do a real check in can_frame dlc */
499 if (rxdata
->can_dlc
!= (op
->last_frames
[index
].can_dlc
&
501 bcm_rx_update_and_send(op
, &op
->last_frames
[index
],
509 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
511 static void bcm_rx_starttimer(struct bcm_op
*op
)
513 if (op
->flags
& RX_NO_AUTOTIMER
)
516 if (op
->kt_ival1
.tv64
)
517 hrtimer_start(&op
->timer
, op
->kt_ival1
, HRTIMER_MODE_REL
);
520 static void bcm_rx_timeout_tsklet(unsigned long data
)
522 struct bcm_op
*op
= (struct bcm_op
*)data
;
523 struct bcm_msg_head msg_head
;
525 /* create notification to user */
526 msg_head
.opcode
= RX_TIMEOUT
;
527 msg_head
.flags
= op
->flags
;
528 msg_head
.count
= op
->count
;
529 msg_head
.ival1
= op
->ival1
;
530 msg_head
.ival2
= op
->ival2
;
531 msg_head
.can_id
= op
->can_id
;
532 msg_head
.nframes
= 0;
534 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
538 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
540 static enum hrtimer_restart
bcm_rx_timeout_handler(struct hrtimer
*hrtimer
)
542 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
544 /* schedule before NET_RX_SOFTIRQ */
545 tasklet_hi_schedule(&op
->tsklet
);
547 /* no restart of the timer is done here! */
549 /* if user wants to be informed, when cyclic CAN-Messages come back */
550 if ((op
->flags
& RX_ANNOUNCE_RESUME
) && op
->last_frames
) {
551 /* clear received can_frames to indicate 'nothing received' */
552 memset(op
->last_frames
, 0, op
->nframes
* CFSIZ
);
555 return HRTIMER_NORESTART
;
559 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
561 static inline int bcm_rx_do_flush(struct bcm_op
*op
, int update
,
564 if ((op
->last_frames
) && (op
->last_frames
[index
].can_dlc
& RX_THR
)) {
566 bcm_rx_changed(op
, &op
->last_frames
[index
]);
573 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
575 * update == 0 : just check if throttled data is available (any irq context)
576 * update == 1 : check and send throttled data to userspace (soft_irq context)
578 static int bcm_rx_thr_flush(struct bcm_op
*op
, int update
)
582 if (op
->nframes
> 1) {
585 /* for MUX filter we start at index 1 */
586 for (i
= 1; i
< op
->nframes
; i
++)
587 updated
+= bcm_rx_do_flush(op
, update
, i
);
590 /* for RX_FILTER_ID and simple filter */
591 updated
+= bcm_rx_do_flush(op
, update
, 0);
597 static void bcm_rx_thr_tsklet(unsigned long data
)
599 struct bcm_op
*op
= (struct bcm_op
*)data
;
601 /* push the changed data to the userspace */
602 bcm_rx_thr_flush(op
, 1);
606 * bcm_rx_thr_handler - the time for blocked content updates is over now:
607 * Check for throttled data and send it to the userspace
609 static enum hrtimer_restart
bcm_rx_thr_handler(struct hrtimer
*hrtimer
)
611 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, thrtimer
);
613 tasklet_schedule(&op
->thrtsklet
);
615 if (bcm_rx_thr_flush(op
, 0)) {
616 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
617 return HRTIMER_RESTART
;
619 /* rearm throttle handling */
620 op
->kt_lastmsg
= ktime_set(0, 0);
621 return HRTIMER_NORESTART
;
626 * bcm_rx_handler - handle a CAN frame receiption
628 static void bcm_rx_handler(struct sk_buff
*skb
, void *data
)
630 struct bcm_op
*op
= (struct bcm_op
*)data
;
631 const struct can_frame
*rxframe
= (struct can_frame
*)skb
->data
;
634 /* disable timeout */
635 hrtimer_cancel(&op
->timer
);
637 if (op
->can_id
!= rxframe
->can_id
)
640 /* save rx timestamp */
641 op
->rx_stamp
= skb
->tstamp
;
642 /* save originator for recvfrom() */
643 op
->rx_ifindex
= skb
->dev
->ifindex
;
644 /* update statistics */
647 if (op
->flags
& RX_RTR_FRAME
) {
648 /* send reply for RTR-request (placed in op->frames[0]) */
653 if (op
->flags
& RX_FILTER_ID
) {
654 /* the easiest case */
655 bcm_rx_update_and_send(op
, &op
->last_frames
[0], rxframe
);
659 if (op
->nframes
== 1) {
660 /* simple compare with index 0 */
661 bcm_rx_cmp_to_index(op
, 0, rxframe
);
665 if (op
->nframes
> 1) {
669 * find the first multiplex mask that fits.
670 * Remark: The MUX-mask is stored in index 0
673 for (i
= 1; i
< op
->nframes
; i
++) {
674 if ((GET_U64(&op
->frames
[0]) & GET_U64(rxframe
)) ==
675 (GET_U64(&op
->frames
[0]) &
676 GET_U64(&op
->frames
[i
]))) {
677 bcm_rx_cmp_to_index(op
, i
, rxframe
);
684 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
);
723 static void bcm_rx_unreg(struct net_device
*dev
, struct bcm_op
*op
)
725 if (op
->rx_reg_dev
== dev
) {
726 can_rx_unregister(dev
, op
->can_id
, REGMASK(op
->can_id
),
729 /* mark as removed subscription */
730 op
->rx_reg_dev
= NULL
;
732 printk(KERN_ERR
"can-bcm: bcm_rx_unreg: registered device "
733 "mismatch %p %p\n", op
->rx_reg_dev
, dev
);
737 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
739 static int bcm_delete_rx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
741 struct bcm_op
*op
, *n
;
743 list_for_each_entry_safe(op
, n
, ops
, list
) {
744 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
747 * Don't care if we're bound or not (due to netdev
748 * problems) can_rx_unregister() is always a save
753 * Only remove subscriptions that had not
754 * been removed due to NETDEV_UNREGISTER
757 if (op
->rx_reg_dev
) {
758 struct net_device
*dev
;
760 dev
= dev_get_by_index(&init_net
,
763 bcm_rx_unreg(dev
, op
);
768 can_rx_unregister(NULL
, op
->can_id
,
778 return 0; /* not found */
782 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
784 static int bcm_delete_tx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
786 struct bcm_op
*op
, *n
;
788 list_for_each_entry_safe(op
, n
, ops
, list
) {
789 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
796 return 0; /* not found */
800 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
802 static int bcm_read_op(struct list_head
*ops
, struct bcm_msg_head
*msg_head
,
805 struct bcm_op
*op
= bcm_find_op(ops
, msg_head
->can_id
, ifindex
);
810 /* put current values into msg_head */
811 msg_head
->flags
= op
->flags
;
812 msg_head
->count
= op
->count
;
813 msg_head
->ival1
= op
->ival1
;
814 msg_head
->ival2
= op
->ival2
;
815 msg_head
->nframes
= op
->nframes
;
817 bcm_send_to_user(op
, msg_head
, op
->frames
, 0);
823 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
825 static int bcm_tx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
826 int ifindex
, struct sock
*sk
)
828 struct bcm_sock
*bo
= bcm_sk(sk
);
833 /* we need a real device to send frames */
837 /* check nframes boundaries - we need at least one can_frame */
838 if (msg_head
->nframes
< 1 || msg_head
->nframes
> MAX_NFRAMES
)
841 /* check the given can_id */
842 op
= bcm_find_op(&bo
->tx_ops
, msg_head
->can_id
, ifindex
);
845 /* update existing BCM operation */
848 * Do we need more space for the can_frames than currently
849 * allocated? -> This is a _really_ unusual use-case and
850 * therefore (complexity / locking) it is not supported.
852 if (msg_head
->nframes
> op
->nframes
)
855 /* update can_frames content */
856 for (i
= 0; i
< msg_head
->nframes
; i
++) {
857 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
858 msg
->msg_iov
, CFSIZ
);
860 if (op
->frames
[i
].can_dlc
> 8)
866 if (msg_head
->flags
& TX_CP_CAN_ID
) {
867 /* copy can_id into frame */
868 op
->frames
[i
].can_id
= msg_head
->can_id
;
873 /* insert new BCM operation for the given can_id */
875 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
879 op
->can_id
= msg_head
->can_id
;
881 /* create array for can_frames and copy the data */
882 if (msg_head
->nframes
> 1) {
883 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
890 op
->frames
= &op
->sframe
;
892 for (i
= 0; i
< msg_head
->nframes
; i
++) {
893 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
894 msg
->msg_iov
, CFSIZ
);
896 if (op
->frames
[i
].can_dlc
> 8)
900 if (op
->frames
!= &op
->sframe
)
906 if (msg_head
->flags
& TX_CP_CAN_ID
) {
907 /* copy can_id into frame */
908 op
->frames
[i
].can_id
= msg_head
->can_id
;
912 /* tx_ops never compare with previous received messages */
913 op
->last_frames
= NULL
;
915 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
917 op
->ifindex
= ifindex
;
919 /* initialize uninitialized (kzalloc) structure */
920 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
921 op
->timer
.function
= bcm_tx_timeout_handler
;
923 /* initialize tasklet for tx countevent notification */
924 tasklet_init(&op
->tsklet
, bcm_tx_timeout_tsklet
,
927 /* currently unused in tx_ops */
928 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
930 /* add this bcm_op to the list of the tx_ops */
931 list_add(&op
->list
, &bo
->tx_ops
);
933 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
935 if (op
->nframes
!= msg_head
->nframes
) {
936 op
->nframes
= msg_head
->nframes
;
937 /* start multiple frame transmission with index 0 */
943 op
->flags
= msg_head
->flags
;
945 if (op
->flags
& TX_RESET_MULTI_IDX
) {
946 /* start multiple frame transmission with index 0 */
950 if (op
->flags
& SETTIMER
) {
951 /* set timer values */
952 op
->count
= msg_head
->count
;
953 op
->ival1
= msg_head
->ival1
;
954 op
->ival2
= msg_head
->ival2
;
955 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
956 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
958 /* disable an active timer due to zero values? */
959 if (!op
->kt_ival1
.tv64
&& !op
->kt_ival2
.tv64
)
960 hrtimer_cancel(&op
->timer
);
963 if ((op
->flags
& STARTTIMER
) &&
964 ((op
->kt_ival1
.tv64
&& op
->count
) || op
->kt_ival2
.tv64
)) {
966 /* spec: send can_frame when starting timer */
967 op
->flags
|= TX_ANNOUNCE
;
969 /* only start timer when having more frames than sent below */
970 if (op
->kt_ival1
.tv64
&& (op
->count
> 1)) {
971 /* op->count-- is done in bcm_tx_timeout_tsklet */
972 hrtimer_start(&op
->timer
, op
->kt_ival1
,
975 hrtimer_start(&op
->timer
, op
->kt_ival2
,
979 if (op
->flags
& TX_ANNOUNCE
) {
981 if (op
->kt_ival1
.tv64
&& (op
->count
> 0))
985 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
989 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
991 static int bcm_rx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
992 int ifindex
, struct sock
*sk
)
994 struct bcm_sock
*bo
= bcm_sk(sk
);
999 if ((msg_head
->flags
& RX_FILTER_ID
) || (!(msg_head
->nframes
))) {
1000 /* be robust against wrong usage ... */
1001 msg_head
->flags
|= RX_FILTER_ID
;
1002 /* ignore trailing garbage */
1003 msg_head
->nframes
= 0;
1006 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1007 if (msg_head
->nframes
> MAX_NFRAMES
+ 1)
1010 if ((msg_head
->flags
& RX_RTR_FRAME
) &&
1011 ((msg_head
->nframes
!= 1) ||
1012 (!(msg_head
->can_id
& CAN_RTR_FLAG
))))
1015 /* check the given can_id */
1016 op
= bcm_find_op(&bo
->rx_ops
, msg_head
->can_id
, ifindex
);
1018 /* update existing BCM operation */
1021 * Do we need more space for the can_frames than currently
1022 * allocated? -> This is a _really_ unusual use-case and
1023 * therefore (complexity / locking) it is not supported.
1025 if (msg_head
->nframes
> op
->nframes
)
1028 if (msg_head
->nframes
) {
1029 /* update can_frames content */
1030 err
= memcpy_fromiovec((u8
*)op
->frames
,
1032 msg_head
->nframes
* CFSIZ
);
1036 /* clear last_frames to indicate 'nothing received' */
1037 memset(op
->last_frames
, 0, msg_head
->nframes
* CFSIZ
);
1040 op
->nframes
= msg_head
->nframes
;
1042 /* Only an update -> do not call can_rx_register() */
1046 /* insert new BCM operation for the given can_id */
1047 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
1051 op
->can_id
= msg_head
->can_id
;
1052 op
->nframes
= msg_head
->nframes
;
1054 if (msg_head
->nframes
> 1) {
1055 /* create array for can_frames and copy the data */
1056 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
1063 /* create and init array for received can_frames */
1064 op
->last_frames
= kzalloc(msg_head
->nframes
* CFSIZ
,
1066 if (!op
->last_frames
) {
1073 op
->frames
= &op
->sframe
;
1074 op
->last_frames
= &op
->last_sframe
;
1077 if (msg_head
->nframes
) {
1078 err
= memcpy_fromiovec((u8
*)op
->frames
, msg
->msg_iov
,
1079 msg_head
->nframes
* CFSIZ
);
1081 if (op
->frames
!= &op
->sframe
)
1083 if (op
->last_frames
!= &op
->last_sframe
)
1084 kfree(op
->last_frames
);
1090 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1092 op
->ifindex
= ifindex
;
1094 /* initialize uninitialized (kzalloc) structure */
1095 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1096 op
->timer
.function
= bcm_rx_timeout_handler
;
1098 /* initialize tasklet for rx timeout notification */
1099 tasklet_init(&op
->tsklet
, bcm_rx_timeout_tsklet
,
1100 (unsigned long) op
);
1102 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1103 op
->thrtimer
.function
= bcm_rx_thr_handler
;
1105 /* initialize tasklet for rx throttle handling */
1106 tasklet_init(&op
->thrtsklet
, bcm_rx_thr_tsklet
,
1107 (unsigned long) op
);
1109 /* add this bcm_op to the list of the rx_ops */
1110 list_add(&op
->list
, &bo
->rx_ops
);
1112 /* call can_rx_register() */
1115 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1118 op
->flags
= msg_head
->flags
;
1120 if (op
->flags
& RX_RTR_FRAME
) {
1122 /* no timers in RTR-mode */
1123 hrtimer_cancel(&op
->thrtimer
);
1124 hrtimer_cancel(&op
->timer
);
1127 * funny feature in RX(!)_SETUP only for RTR-mode:
1128 * copy can_id into frame BUT without RTR-flag to
1129 * prevent a full-load-loopback-test ... ;-]
1131 if ((op
->flags
& TX_CP_CAN_ID
) ||
1132 (op
->frames
[0].can_id
== op
->can_id
))
1133 op
->frames
[0].can_id
= op
->can_id
& ~CAN_RTR_FLAG
;
1136 if (op
->flags
& SETTIMER
) {
1138 /* set timer value */
1139 op
->ival1
= msg_head
->ival1
;
1140 op
->ival2
= msg_head
->ival2
;
1141 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
1142 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
1144 /* disable an active timer due to zero value? */
1145 if (!op
->kt_ival1
.tv64
)
1146 hrtimer_cancel(&op
->timer
);
1149 * In any case cancel the throttle timer, flush
1150 * potentially blocked msgs and reset throttle handling
1152 op
->kt_lastmsg
= ktime_set(0, 0);
1153 hrtimer_cancel(&op
->thrtimer
);
1154 bcm_rx_thr_flush(op
, 1);
1157 if ((op
->flags
& STARTTIMER
) && op
->kt_ival1
.tv64
)
1158 hrtimer_start(&op
->timer
, op
->kt_ival1
,
1162 /* now we can register for can_ids, if we added a new bcm_op */
1163 if (do_rx_register
) {
1165 struct net_device
*dev
;
1167 dev
= dev_get_by_index(&init_net
, ifindex
);
1169 err
= can_rx_register(dev
, op
->can_id
,
1170 REGMASK(op
->can_id
),
1174 op
->rx_reg_dev
= dev
;
1179 err
= can_rx_register(NULL
, op
->can_id
,
1180 REGMASK(op
->can_id
),
1181 bcm_rx_handler
, op
, "bcm");
1183 /* this bcm rx op is broken -> remove it */
1184 list_del(&op
->list
);
1190 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
1194 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1196 static int bcm_tx_send(struct msghdr
*msg
, int ifindex
, struct sock
*sk
)
1198 struct sk_buff
*skb
;
1199 struct net_device
*dev
;
1202 /* we need a real device to send frames */
1206 skb
= alloc_skb(CFSIZ
, GFP_KERNEL
);
1211 err
= memcpy_fromiovec(skb_put(skb
, CFSIZ
), msg
->msg_iov
, CFSIZ
);
1217 dev
= dev_get_by_index(&init_net
, ifindex
);
1225 err
= can_send(skb
, 1); /* send with loopback */
1231 return CFSIZ
+ MHSIZ
;
1235 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1237 static int bcm_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1238 struct msghdr
*msg
, size_t size
)
1240 struct sock
*sk
= sock
->sk
;
1241 struct bcm_sock
*bo
= bcm_sk(sk
);
1242 int ifindex
= bo
->ifindex
; /* default ifindex for this bcm_op */
1243 struct bcm_msg_head msg_head
;
1244 int ret
; /* read bytes or error codes as return value */
1249 /* check for valid message length from userspace */
1250 if (size
< MHSIZ
|| (size
- MHSIZ
) % CFSIZ
)
1253 /* check for alternative ifindex for this bcm_op */
1255 if (!ifindex
&& msg
->msg_name
) {
1256 /* no bound device as default => check msg_name */
1257 struct sockaddr_can
*addr
=
1258 (struct sockaddr_can
*)msg
->msg_name
;
1260 if (msg
->msg_namelen
< sizeof(*addr
))
1263 if (addr
->can_family
!= AF_CAN
)
1266 /* ifindex from sendto() */
1267 ifindex
= addr
->can_ifindex
;
1270 struct net_device
*dev
;
1272 dev
= dev_get_by_index(&init_net
, ifindex
);
1276 if (dev
->type
!= ARPHRD_CAN
) {
1285 /* read message head information */
1287 ret
= memcpy_fromiovec((u8
*)&msg_head
, msg
->msg_iov
, MHSIZ
);
1293 switch (msg_head
.opcode
) {
1296 ret
= bcm_tx_setup(&msg_head
, msg
, ifindex
, sk
);
1300 ret
= bcm_rx_setup(&msg_head
, msg
, ifindex
, sk
);
1304 if (bcm_delete_tx_op(&bo
->tx_ops
, msg_head
.can_id
, ifindex
))
1311 if (bcm_delete_rx_op(&bo
->rx_ops
, msg_head
.can_id
, ifindex
))
1318 /* reuse msg_head for the reply to TX_READ */
1319 msg_head
.opcode
= TX_STATUS
;
1320 ret
= bcm_read_op(&bo
->tx_ops
, &msg_head
, ifindex
);
1324 /* reuse msg_head for the reply to RX_READ */
1325 msg_head
.opcode
= RX_STATUS
;
1326 ret
= bcm_read_op(&bo
->rx_ops
, &msg_head
, ifindex
);
1330 /* we need exactly one can_frame behind the msg head */
1331 if ((msg_head
.nframes
!= 1) || (size
!= CFSIZ
+ MHSIZ
))
1334 ret
= bcm_tx_send(msg
, ifindex
, sk
);
1348 * notification handler for netdevice status changes
1350 static int bcm_notifier(struct notifier_block
*nb
, unsigned long msg
,
1353 struct net_device
*dev
= (struct net_device
*)data
;
1354 struct bcm_sock
*bo
= container_of(nb
, struct bcm_sock
, notifier
);
1355 struct sock
*sk
= &bo
->sk
;
1357 int notify_enodev
= 0;
1359 if (!net_eq(dev_net(dev
), &init_net
))
1362 if (dev
->type
!= ARPHRD_CAN
)
1367 case NETDEV_UNREGISTER
:
1370 /* remove device specific receive entries */
1371 list_for_each_entry(op
, &bo
->rx_ops
, list
)
1372 if (op
->rx_reg_dev
== dev
)
1373 bcm_rx_unreg(dev
, op
);
1375 /* remove device reference, if this is our bound device */
1376 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1384 if (notify_enodev
) {
1385 sk
->sk_err
= ENODEV
;
1386 if (!sock_flag(sk
, SOCK_DEAD
))
1387 sk
->sk_error_report(sk
);
1392 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1393 sk
->sk_err
= ENETDOWN
;
1394 if (!sock_flag(sk
, SOCK_DEAD
))
1395 sk
->sk_error_report(sk
);
1403 * initial settings for all BCM sockets to be set at socket creation time
1405 static int bcm_init(struct sock
*sk
)
1407 struct bcm_sock
*bo
= bcm_sk(sk
);
1411 bo
->dropped_usr_msgs
= 0;
1412 bo
->bcm_proc_read
= NULL
;
1414 INIT_LIST_HEAD(&bo
->tx_ops
);
1415 INIT_LIST_HEAD(&bo
->rx_ops
);
1418 bo
->notifier
.notifier_call
= bcm_notifier
;
1420 register_netdevice_notifier(&bo
->notifier
);
1426 * standard socket functions
1428 static int bcm_release(struct socket
*sock
)
1430 struct sock
*sk
= sock
->sk
;
1431 struct bcm_sock
*bo
;
1432 struct bcm_op
*op
, *next
;
1439 /* remove bcm_ops, timer, rx_unregister(), etc. */
1441 unregister_netdevice_notifier(&bo
->notifier
);
1445 list_for_each_entry_safe(op
, next
, &bo
->tx_ops
, list
)
1448 list_for_each_entry_safe(op
, next
, &bo
->rx_ops
, list
) {
1450 * Don't care if we're bound or not (due to netdev problems)
1451 * can_rx_unregister() is always a save thing to do here.
1455 * Only remove subscriptions that had not
1456 * been removed due to NETDEV_UNREGISTER
1459 if (op
->rx_reg_dev
) {
1460 struct net_device
*dev
;
1462 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
1464 bcm_rx_unreg(dev
, op
);
1469 can_rx_unregister(NULL
, op
->can_id
,
1470 REGMASK(op
->can_id
),
1471 bcm_rx_handler
, op
);
1476 /* remove procfs entry */
1477 if (proc_dir
&& bo
->bcm_proc_read
)
1478 remove_proc_entry(bo
->procname
, proc_dir
);
1480 /* remove device reference */
1495 static int bcm_connect(struct socket
*sock
, struct sockaddr
*uaddr
, int len
,
1498 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
1499 struct sock
*sk
= sock
->sk
;
1500 struct bcm_sock
*bo
= bcm_sk(sk
);
1502 if (len
< sizeof(*addr
))
1508 /* bind a device to this socket */
1509 if (addr
->can_ifindex
) {
1510 struct net_device
*dev
;
1512 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
1516 if (dev
->type
!= ARPHRD_CAN
) {
1521 bo
->ifindex
= dev
->ifindex
;
1525 /* no interface reference for ifindex = 0 ('any' CAN device) */
1532 /* unique socket address as filename */
1533 sprintf(bo
->procname
, "%lu", sock_i_ino(sk
));
1534 bo
->bcm_proc_read
= proc_create_data(bo
->procname
, 0644,
1536 &bcm_proc_fops
, sk
);
1542 static int bcm_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1543 struct msghdr
*msg
, size_t size
, int flags
)
1545 struct sock
*sk
= sock
->sk
;
1546 struct sk_buff
*skb
;
1551 noblock
= flags
& MSG_DONTWAIT
;
1552 flags
&= ~MSG_DONTWAIT
;
1553 skb
= skb_recv_datagram(sk
, flags
, noblock
, &error
);
1557 if (skb
->len
< size
)
1560 err
= memcpy_toiovec(msg
->msg_iov
, skb
->data
, size
);
1562 skb_free_datagram(sk
, skb
);
1566 sock_recv_ts_and_drops(msg
, sk
, skb
);
1568 if (msg
->msg_name
) {
1569 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
1570 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
1573 skb_free_datagram(sk
, skb
);
1578 static const struct proto_ops bcm_ops
= {
1580 .release
= bcm_release
,
1581 .bind
= sock_no_bind
,
1582 .connect
= bcm_connect
,
1583 .socketpair
= sock_no_socketpair
,
1584 .accept
= sock_no_accept
,
1585 .getname
= sock_no_getname
,
1586 .poll
= datagram_poll
,
1587 .ioctl
= can_ioctl
, /* use can_ioctl() from af_can.c */
1588 .listen
= sock_no_listen
,
1589 .shutdown
= sock_no_shutdown
,
1590 .setsockopt
= sock_no_setsockopt
,
1591 .getsockopt
= sock_no_getsockopt
,
1592 .sendmsg
= bcm_sendmsg
,
1593 .recvmsg
= bcm_recvmsg
,
1594 .mmap
= sock_no_mmap
,
1595 .sendpage
= sock_no_sendpage
,
1598 static struct proto bcm_proto __read_mostly
= {
1600 .owner
= THIS_MODULE
,
1601 .obj_size
= sizeof(struct bcm_sock
),
1605 static const struct can_proto bcm_can_proto
= {
1607 .protocol
= CAN_BCM
,
1612 static int __init
bcm_module_init(void)
1618 err
= can_proto_register(&bcm_can_proto
);
1620 printk(KERN_ERR
"can: registration of bcm protocol failed\n");
1624 /* create /proc/net/can-bcm directory */
1625 proc_dir
= proc_mkdir("can-bcm", init_net
.proc_net
);
1629 static void __exit
bcm_module_exit(void)
1631 can_proto_unregister(&bcm_can_proto
);
1634 proc_net_remove(&init_net
, "can-bcm");
1637 module_init(bcm_module_init
);
1638 module_exit(bcm_module_exit
);