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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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
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40 * Send feedback to <socketcan-users@lists.berlios.de>
44 #include <linux/module.h>
45 #include <linux/init.h>
46 #include <linux/interrupt.h>
47 #include <linux/hrtimer.h>
48 #include <linux/list.h>
49 #include <linux/proc_fs.h>
50 #include <linux/seq_file.h>
51 #include <linux/uio.h>
52 #include <linux/net.h>
53 #include <linux/netdevice.h>
54 #include <linux/socket.h>
55 #include <linux/if_arp.h>
56 #include <linux/skbuff.h>
57 #include <linux/can.h>
58 #include <linux/can/core.h>
59 #include <linux/can/bcm.h>
60 #include <linux/slab.h>
62 #include <net/net_namespace.h>
65 * To send multiple CAN frame content within TX_SETUP or to filter
66 * CAN messages with multiplex index within RX_SETUP, the number of
67 * different filters is limited to 256 due to the one byte index value.
69 #define MAX_NFRAMES 256
71 /* use of last_frames[index].can_dlc */
72 #define RX_RECV 0x40 /* received data for this element */
73 #define RX_THR 0x80 /* element not been sent due to throttle feature */
74 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */
76 /* get best masking value for can_rx_register() for a given single can_id */
77 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \
78 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
79 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
81 #define CAN_BCM_VERSION CAN_VERSION
82 static __initdata
const char banner
[] = KERN_INFO
83 "can: broadcast manager protocol (rev " CAN_BCM_VERSION
" t)\n";
85 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
86 MODULE_LICENSE("Dual BSD/GPL");
87 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
88 MODULE_ALIAS("can-proto-2");
90 /* easy access to can_frame payload */
91 static inline u64
GET_U64(const struct can_frame
*cp
)
93 return *(u64
*)cp
->data
;
97 struct list_head list
;
101 unsigned long frames_abs
, frames_filtered
;
102 struct timeval ival1
, ival2
;
103 struct hrtimer timer
, thrtimer
;
104 struct tasklet_struct tsklet
, thrtsklet
;
105 ktime_t rx_stamp
, kt_ival1
, kt_ival2
, kt_lastmsg
;
110 struct can_frame
*frames
;
111 struct can_frame
*last_frames
;
112 struct can_frame sframe
;
113 struct can_frame last_sframe
;
115 struct net_device
*rx_reg_dev
;
118 static struct proc_dir_entry
*proc_dir
;
124 struct notifier_block notifier
;
125 struct list_head rx_ops
;
126 struct list_head tx_ops
;
127 unsigned long dropped_usr_msgs
;
128 struct proc_dir_entry
*bcm_proc_read
;
129 char procname
[32]; /* inode number in decimal with \0 */
132 static inline struct bcm_sock
*bcm_sk(const struct sock
*sk
)
134 return (struct bcm_sock
*)sk
;
137 #define CFSIZ sizeof(struct can_frame)
138 #define OPSIZ sizeof(struct bcm_op)
139 #define MHSIZ sizeof(struct bcm_msg_head)
144 static char *bcm_proc_getifname(char *result
, int ifindex
)
146 struct net_device
*dev
;
152 dev
= dev_get_by_index_rcu(&init_net
, ifindex
);
154 strcpy(result
, dev
->name
);
156 strcpy(result
, "???");
162 static int bcm_proc_show(struct seq_file
*m
, void *v
)
164 char ifname
[IFNAMSIZ
];
165 struct sock
*sk
= (struct sock
*)m
->private;
166 struct bcm_sock
*bo
= bcm_sk(sk
);
169 seq_printf(m
, ">>> socket %pK", sk
->sk_socket
);
170 seq_printf(m
, " / sk %pK", sk
);
171 seq_printf(m
, " / bo %pK", bo
);
172 seq_printf(m
, " / dropped %lu", bo
->dropped_usr_msgs
);
173 seq_printf(m
, " / bound %s", bcm_proc_getifname(ifname
, bo
->ifindex
));
174 seq_printf(m
, " <<<\n");
176 list_for_each_entry(op
, &bo
->rx_ops
, list
) {
178 unsigned long reduction
;
180 /* print only active entries & prevent division by zero */
184 seq_printf(m
, "rx_op: %03X %-5s ",
185 op
->can_id
, bcm_proc_getifname(ifname
, op
->ifindex
));
186 seq_printf(m
, "[%u]%c ", op
->nframes
,
187 (op
->flags
& RX_CHECK_DLC
)?'d':' ');
188 if (op
->kt_ival1
.tv64
)
189 seq_printf(m
, "timeo=%lld ",
191 ktime_to_us(op
->kt_ival1
));
193 if (op
->kt_ival2
.tv64
)
194 seq_printf(m
, "thr=%lld ",
196 ktime_to_us(op
->kt_ival2
));
198 seq_printf(m
, "# recv %ld (%ld) => reduction: ",
199 op
->frames_filtered
, op
->frames_abs
);
201 reduction
= 100 - (op
->frames_filtered
* 100) / op
->frames_abs
;
203 seq_printf(m
, "%s%ld%%\n",
204 (reduction
== 100)?"near ":"", reduction
);
207 list_for_each_entry(op
, &bo
->tx_ops
, list
) {
209 seq_printf(m
, "tx_op: %03X %s [%u] ",
211 bcm_proc_getifname(ifname
, op
->ifindex
),
214 if (op
->kt_ival1
.tv64
)
215 seq_printf(m
, "t1=%lld ",
216 (long long) ktime_to_us(op
->kt_ival1
));
218 if (op
->kt_ival2
.tv64
)
219 seq_printf(m
, "t2=%lld ",
220 (long long) ktime_to_us(op
->kt_ival2
));
222 seq_printf(m
, "# sent %ld\n", op
->frames_abs
);
228 static int bcm_proc_open(struct inode
*inode
, struct file
*file
)
230 return single_open(file
, bcm_proc_show
, PDE(inode
)->data
);
233 static const struct file_operations bcm_proc_fops
= {
234 .owner
= THIS_MODULE
,
235 .open
= bcm_proc_open
,
238 .release
= single_release
,
242 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
243 * of the given bcm tx op
245 static void bcm_can_tx(struct bcm_op
*op
)
248 struct net_device
*dev
;
249 struct can_frame
*cf
= &op
->frames
[op
->currframe
];
251 /* no target device? => exit */
255 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
257 /* RFC: should this bcm_op remove itself here? */
261 skb
= alloc_skb(CFSIZ
, gfp_any());
265 memcpy(skb_put(skb
, CFSIZ
), cf
, CFSIZ
);
267 /* send with loopback */
272 /* update statistics */
276 /* reached last frame? */
277 if (op
->currframe
>= op
->nframes
)
284 * bcm_send_to_user - send a BCM message to the userspace
285 * (consisting of bcm_msg_head + x CAN frames)
287 static void bcm_send_to_user(struct bcm_op
*op
, struct bcm_msg_head
*head
,
288 struct can_frame
*frames
, int has_timestamp
)
291 struct can_frame
*firstframe
;
292 struct sockaddr_can
*addr
;
293 struct sock
*sk
= op
->sk
;
294 unsigned int datalen
= head
->nframes
* CFSIZ
;
297 skb
= alloc_skb(sizeof(*head
) + datalen
, gfp_any());
301 memcpy(skb_put(skb
, sizeof(*head
)), head
, sizeof(*head
));
304 /* can_frames starting here */
305 firstframe
= (struct can_frame
*)skb_tail_pointer(skb
);
307 memcpy(skb_put(skb
, datalen
), frames
, datalen
);
310 * the BCM uses the can_dlc-element of the can_frame
311 * structure for internal purposes. This is only
312 * relevant for updates that are generated by the
313 * BCM, where nframes is 1
315 if (head
->nframes
== 1)
316 firstframe
->can_dlc
&= BCM_CAN_DLC_MASK
;
320 /* restore rx timestamp */
321 skb
->tstamp
= op
->rx_stamp
;
325 * Put the datagram to the queue so that bcm_recvmsg() can
326 * get it from there. We need to pass the interface index to
327 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
328 * containing the interface index.
331 BUILD_BUG_ON(sizeof(skb
->cb
) < sizeof(struct sockaddr_can
));
332 addr
= (struct sockaddr_can
*)skb
->cb
;
333 memset(addr
, 0, sizeof(*addr
));
334 addr
->can_family
= AF_CAN
;
335 addr
->can_ifindex
= op
->rx_ifindex
;
337 err
= sock_queue_rcv_skb(sk
, skb
);
339 struct bcm_sock
*bo
= bcm_sk(sk
);
342 /* don't care about overflows in this statistic */
343 bo
->dropped_usr_msgs
++;
347 static void bcm_tx_timeout_tsklet(unsigned long data
)
349 struct bcm_op
*op
= (struct bcm_op
*)data
;
350 struct bcm_msg_head msg_head
;
352 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
355 if (!op
->count
&& (op
->flags
& TX_COUNTEVT
)) {
357 /* create notification to user */
358 msg_head
.opcode
= TX_EXPIRED
;
359 msg_head
.flags
= op
->flags
;
360 msg_head
.count
= op
->count
;
361 msg_head
.ival1
= op
->ival1
;
362 msg_head
.ival2
= op
->ival2
;
363 msg_head
.can_id
= op
->can_id
;
364 msg_head
.nframes
= 0;
366 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
369 /* send (next) frame */
371 hrtimer_start(&op
->timer
,
372 ktime_add(ktime_get(), op
->kt_ival1
),
376 if (op
->kt_ival2
.tv64
) {
378 /* send (next) frame */
380 hrtimer_start(&op
->timer
,
381 ktime_add(ktime_get(), op
->kt_ival2
),
388 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
390 static enum hrtimer_restart
bcm_tx_timeout_handler(struct hrtimer
*hrtimer
)
392 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
394 tasklet_schedule(&op
->tsklet
);
396 return HRTIMER_NORESTART
;
400 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
402 static void bcm_rx_changed(struct bcm_op
*op
, struct can_frame
*data
)
404 struct bcm_msg_head head
;
406 /* update statistics */
407 op
->frames_filtered
++;
409 /* prevent statistics overflow */
410 if (op
->frames_filtered
> ULONG_MAX
/100)
411 op
->frames_filtered
= op
->frames_abs
= 0;
413 /* this element is not throttled anymore */
414 data
->can_dlc
&= (BCM_CAN_DLC_MASK
|RX_RECV
);
416 head
.opcode
= RX_CHANGED
;
417 head
.flags
= op
->flags
;
418 head
.count
= op
->count
;
419 head
.ival1
= op
->ival1
;
420 head
.ival2
= op
->ival2
;
421 head
.can_id
= op
->can_id
;
424 bcm_send_to_user(op
, &head
, data
, 1);
428 * bcm_rx_update_and_send - process a detected relevant receive content change
429 * 1. update the last received data
430 * 2. send a notification to the user (if possible)
432 static void bcm_rx_update_and_send(struct bcm_op
*op
,
433 struct can_frame
*lastdata
,
434 const struct can_frame
*rxdata
)
436 memcpy(lastdata
, rxdata
, CFSIZ
);
438 /* mark as used and throttled by default */
439 lastdata
->can_dlc
|= (RX_RECV
|RX_THR
);
441 /* throtteling mode inactive ? */
442 if (!op
->kt_ival2
.tv64
) {
443 /* send RX_CHANGED to the user immediately */
444 bcm_rx_changed(op
, lastdata
);
448 /* with active throttling timer we are just done here */
449 if (hrtimer_active(&op
->thrtimer
))
452 /* first receiption with enabled throttling mode */
453 if (!op
->kt_lastmsg
.tv64
)
454 goto rx_changed_settime
;
456 /* got a second frame inside a potential throttle period? */
457 if (ktime_us_delta(ktime_get(), op
->kt_lastmsg
) <
458 ktime_to_us(op
->kt_ival2
)) {
459 /* do not send the saved data - only start throttle timer */
460 hrtimer_start(&op
->thrtimer
,
461 ktime_add(op
->kt_lastmsg
, op
->kt_ival2
),
466 /* the gap was that big, that throttling was not needed here */
468 bcm_rx_changed(op
, lastdata
);
469 op
->kt_lastmsg
= ktime_get();
473 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
474 * received data stored in op->last_frames[]
476 static void bcm_rx_cmp_to_index(struct bcm_op
*op
, unsigned int index
,
477 const struct can_frame
*rxdata
)
480 * no one uses the MSBs of can_dlc for comparation,
481 * so we use it here to detect the first time of reception
484 if (!(op
->last_frames
[index
].can_dlc
& RX_RECV
)) {
485 /* received data for the first time => send update to user */
486 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
490 /* do a real check in can_frame data section */
492 if ((GET_U64(&op
->frames
[index
]) & GET_U64(rxdata
)) !=
493 (GET_U64(&op
->frames
[index
]) & GET_U64(&op
->last_frames
[index
]))) {
494 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
498 if (op
->flags
& RX_CHECK_DLC
) {
499 /* do a real check in can_frame dlc */
500 if (rxdata
->can_dlc
!= (op
->last_frames
[index
].can_dlc
&
502 bcm_rx_update_and_send(op
, &op
->last_frames
[index
],
510 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
512 static void bcm_rx_starttimer(struct bcm_op
*op
)
514 if (op
->flags
& RX_NO_AUTOTIMER
)
517 if (op
->kt_ival1
.tv64
)
518 hrtimer_start(&op
->timer
, op
->kt_ival1
, HRTIMER_MODE_REL
);
521 static void bcm_rx_timeout_tsklet(unsigned long data
)
523 struct bcm_op
*op
= (struct bcm_op
*)data
;
524 struct bcm_msg_head msg_head
;
526 /* create notification to user */
527 msg_head
.opcode
= RX_TIMEOUT
;
528 msg_head
.flags
= op
->flags
;
529 msg_head
.count
= op
->count
;
530 msg_head
.ival1
= op
->ival1
;
531 msg_head
.ival2
= op
->ival2
;
532 msg_head
.can_id
= op
->can_id
;
533 msg_head
.nframes
= 0;
535 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
539 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
541 static enum hrtimer_restart
bcm_rx_timeout_handler(struct hrtimer
*hrtimer
)
543 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
545 /* schedule before NET_RX_SOFTIRQ */
546 tasklet_hi_schedule(&op
->tsklet
);
548 /* no restart of the timer is done here! */
550 /* if user wants to be informed, when cyclic CAN-Messages come back */
551 if ((op
->flags
& RX_ANNOUNCE_RESUME
) && op
->last_frames
) {
552 /* clear received can_frames to indicate 'nothing received' */
553 memset(op
->last_frames
, 0, op
->nframes
* CFSIZ
);
556 return HRTIMER_NORESTART
;
560 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
562 static inline int bcm_rx_do_flush(struct bcm_op
*op
, int update
,
565 if ((op
->last_frames
) && (op
->last_frames
[index
].can_dlc
& RX_THR
)) {
567 bcm_rx_changed(op
, &op
->last_frames
[index
]);
574 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
576 * update == 0 : just check if throttled data is available (any irq context)
577 * update == 1 : check and send throttled data to userspace (soft_irq context)
579 static int bcm_rx_thr_flush(struct bcm_op
*op
, int update
)
583 if (op
->nframes
> 1) {
586 /* for MUX filter we start at index 1 */
587 for (i
= 1; i
< op
->nframes
; i
++)
588 updated
+= bcm_rx_do_flush(op
, update
, i
);
591 /* for RX_FILTER_ID and simple filter */
592 updated
+= bcm_rx_do_flush(op
, update
, 0);
598 static void bcm_rx_thr_tsklet(unsigned long data
)
600 struct bcm_op
*op
= (struct bcm_op
*)data
;
602 /* push the changed data to the userspace */
603 bcm_rx_thr_flush(op
, 1);
607 * bcm_rx_thr_handler - the time for blocked content updates is over now:
608 * Check for throttled data and send it to the userspace
610 static enum hrtimer_restart
bcm_rx_thr_handler(struct hrtimer
*hrtimer
)
612 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, thrtimer
);
614 tasklet_schedule(&op
->thrtsklet
);
616 if (bcm_rx_thr_flush(op
, 0)) {
617 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
618 return HRTIMER_RESTART
;
620 /* rearm throttle handling */
621 op
->kt_lastmsg
= ktime_set(0, 0);
622 return HRTIMER_NORESTART
;
627 * bcm_rx_handler - handle a CAN frame receiption
629 static void bcm_rx_handler(struct sk_buff
*skb
, void *data
)
631 struct bcm_op
*op
= (struct bcm_op
*)data
;
632 const struct can_frame
*rxframe
= (struct can_frame
*)skb
->data
;
635 /* disable timeout */
636 hrtimer_cancel(&op
->timer
);
638 if (op
->can_id
!= rxframe
->can_id
)
641 /* save rx timestamp */
642 op
->rx_stamp
= skb
->tstamp
;
643 /* save originator for recvfrom() */
644 op
->rx_ifindex
= skb
->dev
->ifindex
;
645 /* update statistics */
648 if (op
->flags
& RX_RTR_FRAME
) {
649 /* send reply for RTR-request (placed in op->frames[0]) */
654 if (op
->flags
& RX_FILTER_ID
) {
655 /* the easiest case */
656 bcm_rx_update_and_send(op
, &op
->last_frames
[0], rxframe
);
660 if (op
->nframes
== 1) {
661 /* simple compare with index 0 */
662 bcm_rx_cmp_to_index(op
, 0, rxframe
);
666 if (op
->nframes
> 1) {
670 * find the first multiplex mask that fits.
671 * Remark: The MUX-mask is stored in index 0
674 for (i
= 1; i
< op
->nframes
; i
++) {
675 if ((GET_U64(&op
->frames
[0]) & GET_U64(rxframe
)) ==
676 (GET_U64(&op
->frames
[0]) &
677 GET_U64(&op
->frames
[i
]))) {
678 bcm_rx_cmp_to_index(op
, i
, rxframe
);
685 bcm_rx_starttimer(op
);
689 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
691 static struct bcm_op
*bcm_find_op(struct list_head
*ops
, canid_t can_id
,
696 list_for_each_entry(op
, ops
, list
) {
697 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
))
704 static void bcm_remove_op(struct bcm_op
*op
)
706 hrtimer_cancel(&op
->timer
);
707 hrtimer_cancel(&op
->thrtimer
);
710 tasklet_kill(&op
->tsklet
);
712 if (op
->thrtsklet
.func
)
713 tasklet_kill(&op
->thrtsklet
);
715 if ((op
->frames
) && (op
->frames
!= &op
->sframe
))
718 if ((op
->last_frames
) && (op
->last_frames
!= &op
->last_sframe
))
719 kfree(op
->last_frames
);
724 static void bcm_rx_unreg(struct net_device
*dev
, struct bcm_op
*op
)
726 if (op
->rx_reg_dev
== dev
) {
727 can_rx_unregister(dev
, op
->can_id
, REGMASK(op
->can_id
),
730 /* mark as removed subscription */
731 op
->rx_reg_dev
= NULL
;
733 printk(KERN_ERR
"can-bcm: bcm_rx_unreg: registered device "
734 "mismatch %p %p\n", op
->rx_reg_dev
, dev
);
738 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
740 static int bcm_delete_rx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
742 struct bcm_op
*op
, *n
;
744 list_for_each_entry_safe(op
, n
, ops
, list
) {
745 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
748 * Don't care if we're bound or not (due to netdev
749 * problems) can_rx_unregister() is always a save
754 * Only remove subscriptions that had not
755 * been removed due to NETDEV_UNREGISTER
758 if (op
->rx_reg_dev
) {
759 struct net_device
*dev
;
761 dev
= dev_get_by_index(&init_net
,
764 bcm_rx_unreg(dev
, op
);
769 can_rx_unregister(NULL
, op
->can_id
,
779 return 0; /* not found */
783 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
785 static int bcm_delete_tx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
787 struct bcm_op
*op
, *n
;
789 list_for_each_entry_safe(op
, n
, ops
, list
) {
790 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
797 return 0; /* not found */
801 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
803 static int bcm_read_op(struct list_head
*ops
, struct bcm_msg_head
*msg_head
,
806 struct bcm_op
*op
= bcm_find_op(ops
, msg_head
->can_id
, ifindex
);
811 /* put current values into msg_head */
812 msg_head
->flags
= op
->flags
;
813 msg_head
->count
= op
->count
;
814 msg_head
->ival1
= op
->ival1
;
815 msg_head
->ival2
= op
->ival2
;
816 msg_head
->nframes
= op
->nframes
;
818 bcm_send_to_user(op
, msg_head
, op
->frames
, 0);
824 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
826 static int bcm_tx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
827 int ifindex
, struct sock
*sk
)
829 struct bcm_sock
*bo
= bcm_sk(sk
);
834 /* we need a real device to send frames */
838 /* check nframes boundaries - we need at least one can_frame */
839 if (msg_head
->nframes
< 1 || msg_head
->nframes
> MAX_NFRAMES
)
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 /* only start timer when having more frames than sent below */
971 if (op
->kt_ival1
.tv64
&& (op
->count
> 1)) {
972 /* op->count-- is done in bcm_tx_timeout_tsklet */
973 hrtimer_start(&op
->timer
, op
->kt_ival1
,
976 hrtimer_start(&op
->timer
, op
->kt_ival2
,
980 if (op
->flags
& TX_ANNOUNCE
) {
982 if (op
->kt_ival1
.tv64
&& (op
->count
> 0))
986 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
990 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
992 static int bcm_rx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
993 int ifindex
, struct sock
*sk
)
995 struct bcm_sock
*bo
= bcm_sk(sk
);
1000 if ((msg_head
->flags
& RX_FILTER_ID
) || (!(msg_head
->nframes
))) {
1001 /* be robust against wrong usage ... */
1002 msg_head
->flags
|= RX_FILTER_ID
;
1003 /* ignore trailing garbage */
1004 msg_head
->nframes
= 0;
1007 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1008 if (msg_head
->nframes
> MAX_NFRAMES
+ 1)
1011 if ((msg_head
->flags
& RX_RTR_FRAME
) &&
1012 ((msg_head
->nframes
!= 1) ||
1013 (!(msg_head
->can_id
& CAN_RTR_FLAG
))))
1016 /* check the given can_id */
1017 op
= bcm_find_op(&bo
->rx_ops
, msg_head
->can_id
, ifindex
);
1019 /* update existing BCM operation */
1022 * Do we need more space for the can_frames than currently
1023 * allocated? -> This is a _really_ unusual use-case and
1024 * therefore (complexity / locking) it is not supported.
1026 if (msg_head
->nframes
> op
->nframes
)
1029 if (msg_head
->nframes
) {
1030 /* update can_frames content */
1031 err
= memcpy_fromiovec((u8
*)op
->frames
,
1033 msg_head
->nframes
* CFSIZ
);
1037 /* clear last_frames to indicate 'nothing received' */
1038 memset(op
->last_frames
, 0, msg_head
->nframes
* CFSIZ
);
1041 op
->nframes
= msg_head
->nframes
;
1043 /* Only an update -> do not call can_rx_register() */
1047 /* insert new BCM operation for the given can_id */
1048 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
1052 op
->can_id
= msg_head
->can_id
;
1053 op
->nframes
= msg_head
->nframes
;
1055 if (msg_head
->nframes
> 1) {
1056 /* create array for can_frames and copy the data */
1057 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
1064 /* create and init array for received can_frames */
1065 op
->last_frames
= kzalloc(msg_head
->nframes
* CFSIZ
,
1067 if (!op
->last_frames
) {
1074 op
->frames
= &op
->sframe
;
1075 op
->last_frames
= &op
->last_sframe
;
1078 if (msg_head
->nframes
) {
1079 err
= memcpy_fromiovec((u8
*)op
->frames
, msg
->msg_iov
,
1080 msg_head
->nframes
* CFSIZ
);
1082 if (op
->frames
!= &op
->sframe
)
1084 if (op
->last_frames
!= &op
->last_sframe
)
1085 kfree(op
->last_frames
);
1091 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1093 op
->ifindex
= ifindex
;
1095 /* initialize uninitialized (kzalloc) structure */
1096 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1097 op
->timer
.function
= bcm_rx_timeout_handler
;
1099 /* initialize tasklet for rx timeout notification */
1100 tasklet_init(&op
->tsklet
, bcm_rx_timeout_tsklet
,
1101 (unsigned long) op
);
1103 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1104 op
->thrtimer
.function
= bcm_rx_thr_handler
;
1106 /* initialize tasklet for rx throttle handling */
1107 tasklet_init(&op
->thrtsklet
, bcm_rx_thr_tsklet
,
1108 (unsigned long) op
);
1110 /* add this bcm_op to the list of the rx_ops */
1111 list_add(&op
->list
, &bo
->rx_ops
);
1113 /* call can_rx_register() */
1116 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1119 op
->flags
= msg_head
->flags
;
1121 if (op
->flags
& RX_RTR_FRAME
) {
1123 /* no timers in RTR-mode */
1124 hrtimer_cancel(&op
->thrtimer
);
1125 hrtimer_cancel(&op
->timer
);
1128 * funny feature in RX(!)_SETUP only for RTR-mode:
1129 * copy can_id into frame BUT without RTR-flag to
1130 * prevent a full-load-loopback-test ... ;-]
1132 if ((op
->flags
& TX_CP_CAN_ID
) ||
1133 (op
->frames
[0].can_id
== op
->can_id
))
1134 op
->frames
[0].can_id
= op
->can_id
& ~CAN_RTR_FLAG
;
1137 if (op
->flags
& SETTIMER
) {
1139 /* set timer value */
1140 op
->ival1
= msg_head
->ival1
;
1141 op
->ival2
= msg_head
->ival2
;
1142 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
1143 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
1145 /* disable an active timer due to zero value? */
1146 if (!op
->kt_ival1
.tv64
)
1147 hrtimer_cancel(&op
->timer
);
1150 * In any case cancel the throttle timer, flush
1151 * potentially blocked msgs and reset throttle handling
1153 op
->kt_lastmsg
= ktime_set(0, 0);
1154 hrtimer_cancel(&op
->thrtimer
);
1155 bcm_rx_thr_flush(op
, 1);
1158 if ((op
->flags
& STARTTIMER
) && op
->kt_ival1
.tv64
)
1159 hrtimer_start(&op
->timer
, op
->kt_ival1
,
1163 /* now we can register for can_ids, if we added a new bcm_op */
1164 if (do_rx_register
) {
1166 struct net_device
*dev
;
1168 dev
= dev_get_by_index(&init_net
, ifindex
);
1170 err
= can_rx_register(dev
, op
->can_id
,
1171 REGMASK(op
->can_id
),
1175 op
->rx_reg_dev
= dev
;
1180 err
= can_rx_register(NULL
, op
->can_id
,
1181 REGMASK(op
->can_id
),
1182 bcm_rx_handler
, op
, "bcm");
1184 /* this bcm rx op is broken -> remove it */
1185 list_del(&op
->list
);
1191 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
1195 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1197 static int bcm_tx_send(struct msghdr
*msg
, int ifindex
, struct sock
*sk
)
1199 struct sk_buff
*skb
;
1200 struct net_device
*dev
;
1203 /* we need a real device to send frames */
1207 skb
= alloc_skb(CFSIZ
, GFP_KERNEL
);
1212 err
= memcpy_fromiovec(skb_put(skb
, CFSIZ
), msg
->msg_iov
, CFSIZ
);
1218 dev
= dev_get_by_index(&init_net
, ifindex
);
1226 err
= can_send(skb
, 1); /* send with loopback */
1232 return CFSIZ
+ MHSIZ
;
1236 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1238 static int bcm_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1239 struct msghdr
*msg
, size_t size
)
1241 struct sock
*sk
= sock
->sk
;
1242 struct bcm_sock
*bo
= bcm_sk(sk
);
1243 int ifindex
= bo
->ifindex
; /* default ifindex for this bcm_op */
1244 struct bcm_msg_head msg_head
;
1245 int ret
; /* read bytes or error codes as return value */
1250 /* check for valid message length from userspace */
1251 if (size
< MHSIZ
|| (size
- MHSIZ
) % CFSIZ
)
1254 /* check for alternative ifindex for this bcm_op */
1256 if (!ifindex
&& msg
->msg_name
) {
1257 /* no bound device as default => check msg_name */
1258 struct sockaddr_can
*addr
=
1259 (struct sockaddr_can
*)msg
->msg_name
;
1261 if (msg
->msg_namelen
< sizeof(*addr
))
1264 if (addr
->can_family
!= AF_CAN
)
1267 /* ifindex from sendto() */
1268 ifindex
= addr
->can_ifindex
;
1271 struct net_device
*dev
;
1273 dev
= dev_get_by_index(&init_net
, ifindex
);
1277 if (dev
->type
!= ARPHRD_CAN
) {
1286 /* read message head information */
1288 ret
= memcpy_fromiovec((u8
*)&msg_head
, msg
->msg_iov
, MHSIZ
);
1294 switch (msg_head
.opcode
) {
1297 ret
= bcm_tx_setup(&msg_head
, msg
, ifindex
, sk
);
1301 ret
= bcm_rx_setup(&msg_head
, msg
, ifindex
, sk
);
1305 if (bcm_delete_tx_op(&bo
->tx_ops
, msg_head
.can_id
, ifindex
))
1312 if (bcm_delete_rx_op(&bo
->rx_ops
, msg_head
.can_id
, ifindex
))
1319 /* reuse msg_head for the reply to TX_READ */
1320 msg_head
.opcode
= TX_STATUS
;
1321 ret
= bcm_read_op(&bo
->tx_ops
, &msg_head
, ifindex
);
1325 /* reuse msg_head for the reply to RX_READ */
1326 msg_head
.opcode
= RX_STATUS
;
1327 ret
= bcm_read_op(&bo
->rx_ops
, &msg_head
, ifindex
);
1331 /* we need exactly one can_frame behind the msg head */
1332 if ((msg_head
.nframes
!= 1) || (size
!= CFSIZ
+ MHSIZ
))
1335 ret
= bcm_tx_send(msg
, ifindex
, sk
);
1349 * notification handler for netdevice status changes
1351 static int bcm_notifier(struct notifier_block
*nb
, unsigned long msg
,
1354 struct net_device
*dev
= (struct net_device
*)data
;
1355 struct bcm_sock
*bo
= container_of(nb
, struct bcm_sock
, notifier
);
1356 struct sock
*sk
= &bo
->sk
;
1358 int notify_enodev
= 0;
1360 if (!net_eq(dev_net(dev
), &init_net
))
1363 if (dev
->type
!= ARPHRD_CAN
)
1368 case NETDEV_UNREGISTER
:
1371 /* remove device specific receive entries */
1372 list_for_each_entry(op
, &bo
->rx_ops
, list
)
1373 if (op
->rx_reg_dev
== dev
)
1374 bcm_rx_unreg(dev
, op
);
1376 /* remove device reference, if this is our bound device */
1377 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1385 if (notify_enodev
) {
1386 sk
->sk_err
= ENODEV
;
1387 if (!sock_flag(sk
, SOCK_DEAD
))
1388 sk
->sk_error_report(sk
);
1393 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1394 sk
->sk_err
= ENETDOWN
;
1395 if (!sock_flag(sk
, SOCK_DEAD
))
1396 sk
->sk_error_report(sk
);
1404 * initial settings for all BCM sockets to be set at socket creation time
1406 static int bcm_init(struct sock
*sk
)
1408 struct bcm_sock
*bo
= bcm_sk(sk
);
1412 bo
->dropped_usr_msgs
= 0;
1413 bo
->bcm_proc_read
= NULL
;
1415 INIT_LIST_HEAD(&bo
->tx_ops
);
1416 INIT_LIST_HEAD(&bo
->rx_ops
);
1419 bo
->notifier
.notifier_call
= bcm_notifier
;
1421 register_netdevice_notifier(&bo
->notifier
);
1427 * standard socket functions
1429 static int bcm_release(struct socket
*sock
)
1431 struct sock
*sk
= sock
->sk
;
1432 struct bcm_sock
*bo
;
1433 struct bcm_op
*op
, *next
;
1440 /* remove bcm_ops, timer, rx_unregister(), etc. */
1442 unregister_netdevice_notifier(&bo
->notifier
);
1446 list_for_each_entry_safe(op
, next
, &bo
->tx_ops
, list
)
1449 list_for_each_entry_safe(op
, next
, &bo
->rx_ops
, list
) {
1451 * Don't care if we're bound or not (due to netdev problems)
1452 * can_rx_unregister() is always a save thing to do here.
1456 * Only remove subscriptions that had not
1457 * been removed due to NETDEV_UNREGISTER
1460 if (op
->rx_reg_dev
) {
1461 struct net_device
*dev
;
1463 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
1465 bcm_rx_unreg(dev
, op
);
1470 can_rx_unregister(NULL
, op
->can_id
,
1471 REGMASK(op
->can_id
),
1472 bcm_rx_handler
, op
);
1477 /* remove procfs entry */
1478 if (proc_dir
&& bo
->bcm_proc_read
)
1479 remove_proc_entry(bo
->procname
, proc_dir
);
1481 /* remove device reference */
1496 static int bcm_connect(struct socket
*sock
, struct sockaddr
*uaddr
, int len
,
1499 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
1500 struct sock
*sk
= sock
->sk
;
1501 struct bcm_sock
*bo
= bcm_sk(sk
);
1503 if (len
< sizeof(*addr
))
1509 /* bind a device to this socket */
1510 if (addr
->can_ifindex
) {
1511 struct net_device
*dev
;
1513 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
1517 if (dev
->type
!= ARPHRD_CAN
) {
1522 bo
->ifindex
= dev
->ifindex
;
1526 /* no interface reference for ifindex = 0 ('any' CAN device) */
1533 /* unique socket address as filename */
1534 sprintf(bo
->procname
, "%lu", sock_i_ino(sk
));
1535 bo
->bcm_proc_read
= proc_create_data(bo
->procname
, 0644,
1537 &bcm_proc_fops
, sk
);
1543 static int bcm_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1544 struct msghdr
*msg
, size_t size
, int flags
)
1546 struct sock
*sk
= sock
->sk
;
1547 struct sk_buff
*skb
;
1552 noblock
= flags
& MSG_DONTWAIT
;
1553 flags
&= ~MSG_DONTWAIT
;
1554 skb
= skb_recv_datagram(sk
, flags
, noblock
, &error
);
1558 if (skb
->len
< size
)
1561 err
= memcpy_toiovec(msg
->msg_iov
, skb
->data
, size
);
1563 skb_free_datagram(sk
, skb
);
1567 sock_recv_ts_and_drops(msg
, sk
, skb
);
1569 if (msg
->msg_name
) {
1570 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
1571 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
1574 skb_free_datagram(sk
, skb
);
1579 static const struct proto_ops bcm_ops
= {
1581 .release
= bcm_release
,
1582 .bind
= sock_no_bind
,
1583 .connect
= bcm_connect
,
1584 .socketpair
= sock_no_socketpair
,
1585 .accept
= sock_no_accept
,
1586 .getname
= sock_no_getname
,
1587 .poll
= datagram_poll
,
1588 .ioctl
= can_ioctl
, /* use can_ioctl() from af_can.c */
1589 .listen
= sock_no_listen
,
1590 .shutdown
= sock_no_shutdown
,
1591 .setsockopt
= sock_no_setsockopt
,
1592 .getsockopt
= sock_no_getsockopt
,
1593 .sendmsg
= bcm_sendmsg
,
1594 .recvmsg
= bcm_recvmsg
,
1595 .mmap
= sock_no_mmap
,
1596 .sendpage
= sock_no_sendpage
,
1599 static struct proto bcm_proto __read_mostly
= {
1601 .owner
= THIS_MODULE
,
1602 .obj_size
= sizeof(struct bcm_sock
),
1606 static const struct can_proto bcm_can_proto
= {
1608 .protocol
= CAN_BCM
,
1613 static int __init
bcm_module_init(void)
1619 err
= can_proto_register(&bcm_can_proto
);
1621 printk(KERN_ERR
"can: registration of bcm protocol failed\n");
1625 /* create /proc/net/can-bcm directory */
1626 proc_dir
= proc_mkdir("can-bcm", init_net
.proc_net
);
1630 static void __exit
bcm_module_exit(void)
1632 can_proto_unregister(&bcm_can_proto
);
1635 proc_net_remove(&init_net
, "can-bcm");
1638 module_init(bcm_module_init
);
1639 module_exit(bcm_module_exit
);