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
42 #include <linux/module.h>
43 #include <linux/init.h>
44 #include <linux/interrupt.h>
45 #include <linux/hrtimer.h>
46 #include <linux/list.h>
47 #include <linux/proc_fs.h>
48 #include <linux/seq_file.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/skb.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 __initconst
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_DATA(inode
));
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
+ sizeof(struct can_skb_priv
), gfp_any());
264 can_skb_reserve(skb
);
265 can_skb_prv(skb
)->ifindex
= dev
->ifindex
;
267 memcpy(skb_put(skb
, CFSIZ
), cf
, CFSIZ
);
269 /* send with loopback */
271 can_skb_set_owner(skb
, op
->sk
);
274 /* update statistics */
278 /* reached last frame? */
279 if (op
->currframe
>= op
->nframes
)
286 * bcm_send_to_user - send a BCM message to the userspace
287 * (consisting of bcm_msg_head + x CAN frames)
289 static void bcm_send_to_user(struct bcm_op
*op
, struct bcm_msg_head
*head
,
290 struct can_frame
*frames
, int has_timestamp
)
293 struct can_frame
*firstframe
;
294 struct sockaddr_can
*addr
;
295 struct sock
*sk
= op
->sk
;
296 unsigned int datalen
= head
->nframes
* CFSIZ
;
299 skb
= alloc_skb(sizeof(*head
) + datalen
, gfp_any());
303 memcpy(skb_put(skb
, sizeof(*head
)), head
, sizeof(*head
));
306 /* can_frames starting here */
307 firstframe
= (struct can_frame
*)skb_tail_pointer(skb
);
309 memcpy(skb_put(skb
, datalen
), frames
, datalen
);
312 * the BCM uses the can_dlc-element of the can_frame
313 * structure for internal purposes. This is only
314 * relevant for updates that are generated by the
315 * BCM, where nframes is 1
317 if (head
->nframes
== 1)
318 firstframe
->can_dlc
&= BCM_CAN_DLC_MASK
;
322 /* restore rx timestamp */
323 skb
->tstamp
= op
->rx_stamp
;
327 * Put the datagram to the queue so that bcm_recvmsg() can
328 * get it from there. We need to pass the interface index to
329 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
330 * containing the interface index.
333 BUILD_BUG_ON(sizeof(skb
->cb
) < sizeof(struct sockaddr_can
));
334 addr
= (struct sockaddr_can
*)skb
->cb
;
335 memset(addr
, 0, sizeof(*addr
));
336 addr
->can_family
= AF_CAN
;
337 addr
->can_ifindex
= op
->rx_ifindex
;
339 err
= sock_queue_rcv_skb(sk
, skb
);
341 struct bcm_sock
*bo
= bcm_sk(sk
);
344 /* don't care about overflows in this statistic */
345 bo
->dropped_usr_msgs
++;
349 static void bcm_tx_start_timer(struct bcm_op
*op
)
351 if (op
->kt_ival1
.tv64
&& op
->count
)
352 hrtimer_start(&op
->timer
,
353 ktime_add(ktime_get(), op
->kt_ival1
),
355 else if (op
->kt_ival2
.tv64
)
356 hrtimer_start(&op
->timer
,
357 ktime_add(ktime_get(), op
->kt_ival2
),
361 static void bcm_tx_timeout_tsklet(unsigned long data
)
363 struct bcm_op
*op
= (struct bcm_op
*)data
;
364 struct bcm_msg_head msg_head
;
366 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
369 if (!op
->count
&& (op
->flags
& TX_COUNTEVT
)) {
371 /* create notification to user */
372 msg_head
.opcode
= TX_EXPIRED
;
373 msg_head
.flags
= op
->flags
;
374 msg_head
.count
= op
->count
;
375 msg_head
.ival1
= op
->ival1
;
376 msg_head
.ival2
= op
->ival2
;
377 msg_head
.can_id
= op
->can_id
;
378 msg_head
.nframes
= 0;
380 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
384 } else if (op
->kt_ival2
.tv64
)
387 bcm_tx_start_timer(op
);
391 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
393 static enum hrtimer_restart
bcm_tx_timeout_handler(struct hrtimer
*hrtimer
)
395 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
397 tasklet_schedule(&op
->tsklet
);
399 return HRTIMER_NORESTART
;
403 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
405 static void bcm_rx_changed(struct bcm_op
*op
, struct can_frame
*data
)
407 struct bcm_msg_head head
;
409 /* update statistics */
410 op
->frames_filtered
++;
412 /* prevent statistics overflow */
413 if (op
->frames_filtered
> ULONG_MAX
/100)
414 op
->frames_filtered
= op
->frames_abs
= 0;
416 /* this element is not throttled anymore */
417 data
->can_dlc
&= (BCM_CAN_DLC_MASK
|RX_RECV
);
419 head
.opcode
= RX_CHANGED
;
420 head
.flags
= op
->flags
;
421 head
.count
= op
->count
;
422 head
.ival1
= op
->ival1
;
423 head
.ival2
= op
->ival2
;
424 head
.can_id
= op
->can_id
;
427 bcm_send_to_user(op
, &head
, data
, 1);
431 * bcm_rx_update_and_send - process a detected relevant receive content change
432 * 1. update the last received data
433 * 2. send a notification to the user (if possible)
435 static void bcm_rx_update_and_send(struct bcm_op
*op
,
436 struct can_frame
*lastdata
,
437 const struct can_frame
*rxdata
)
439 memcpy(lastdata
, rxdata
, CFSIZ
);
441 /* mark as used and throttled by default */
442 lastdata
->can_dlc
|= (RX_RECV
|RX_THR
);
444 /* throtteling mode inactive ? */
445 if (!op
->kt_ival2
.tv64
) {
446 /* send RX_CHANGED to the user immediately */
447 bcm_rx_changed(op
, lastdata
);
451 /* with active throttling timer we are just done here */
452 if (hrtimer_active(&op
->thrtimer
))
455 /* first receiption with enabled throttling mode */
456 if (!op
->kt_lastmsg
.tv64
)
457 goto rx_changed_settime
;
459 /* got a second frame inside a potential throttle period? */
460 if (ktime_us_delta(ktime_get(), op
->kt_lastmsg
) <
461 ktime_to_us(op
->kt_ival2
)) {
462 /* do not send the saved data - only start throttle timer */
463 hrtimer_start(&op
->thrtimer
,
464 ktime_add(op
->kt_lastmsg
, op
->kt_ival2
),
469 /* the gap was that big, that throttling was not needed here */
471 bcm_rx_changed(op
, lastdata
);
472 op
->kt_lastmsg
= ktime_get();
476 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
477 * received data stored in op->last_frames[]
479 static void bcm_rx_cmp_to_index(struct bcm_op
*op
, unsigned int index
,
480 const struct can_frame
*rxdata
)
483 * no one uses the MSBs of can_dlc for comparation,
484 * so we use it here to detect the first time of reception
487 if (!(op
->last_frames
[index
].can_dlc
& RX_RECV
)) {
488 /* received data for the first time => send update to user */
489 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
493 /* do a real check in can_frame data section */
495 if ((GET_U64(&op
->frames
[index
]) & GET_U64(rxdata
)) !=
496 (GET_U64(&op
->frames
[index
]) & GET_U64(&op
->last_frames
[index
]))) {
497 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
501 if (op
->flags
& RX_CHECK_DLC
) {
502 /* do a real check in can_frame dlc */
503 if (rxdata
->can_dlc
!= (op
->last_frames
[index
].can_dlc
&
505 bcm_rx_update_and_send(op
, &op
->last_frames
[index
],
513 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption
515 static void bcm_rx_starttimer(struct bcm_op
*op
)
517 if (op
->flags
& RX_NO_AUTOTIMER
)
520 if (op
->kt_ival1
.tv64
)
521 hrtimer_start(&op
->timer
, op
->kt_ival1
, HRTIMER_MODE_REL
);
524 static void bcm_rx_timeout_tsklet(unsigned long data
)
526 struct bcm_op
*op
= (struct bcm_op
*)data
;
527 struct bcm_msg_head msg_head
;
529 /* create notification to user */
530 msg_head
.opcode
= RX_TIMEOUT
;
531 msg_head
.flags
= op
->flags
;
532 msg_head
.count
= op
->count
;
533 msg_head
.ival1
= op
->ival1
;
534 msg_head
.ival2
= op
->ival2
;
535 msg_head
.can_id
= op
->can_id
;
536 msg_head
.nframes
= 0;
538 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
542 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out
544 static enum hrtimer_restart
bcm_rx_timeout_handler(struct hrtimer
*hrtimer
)
546 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
548 /* schedule before NET_RX_SOFTIRQ */
549 tasklet_hi_schedule(&op
->tsklet
);
551 /* no restart of the timer is done here! */
553 /* if user wants to be informed, when cyclic CAN-Messages come back */
554 if ((op
->flags
& RX_ANNOUNCE_RESUME
) && op
->last_frames
) {
555 /* clear received can_frames to indicate 'nothing received' */
556 memset(op
->last_frames
, 0, op
->nframes
* CFSIZ
);
559 return HRTIMER_NORESTART
;
563 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
565 static inline int bcm_rx_do_flush(struct bcm_op
*op
, int update
,
568 if ((op
->last_frames
) && (op
->last_frames
[index
].can_dlc
& RX_THR
)) {
570 bcm_rx_changed(op
, &op
->last_frames
[index
]);
577 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
579 * update == 0 : just check if throttled data is available (any irq context)
580 * update == 1 : check and send throttled data to userspace (soft_irq context)
582 static int bcm_rx_thr_flush(struct bcm_op
*op
, int update
)
586 if (op
->nframes
> 1) {
589 /* for MUX filter we start at index 1 */
590 for (i
= 1; i
< op
->nframes
; i
++)
591 updated
+= bcm_rx_do_flush(op
, update
, i
);
594 /* for RX_FILTER_ID and simple filter */
595 updated
+= bcm_rx_do_flush(op
, update
, 0);
601 static void bcm_rx_thr_tsklet(unsigned long data
)
603 struct bcm_op
*op
= (struct bcm_op
*)data
;
605 /* push the changed data to the userspace */
606 bcm_rx_thr_flush(op
, 1);
610 * bcm_rx_thr_handler - the time for blocked content updates is over now:
611 * Check for throttled data and send it to the userspace
613 static enum hrtimer_restart
bcm_rx_thr_handler(struct hrtimer
*hrtimer
)
615 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, thrtimer
);
617 tasklet_schedule(&op
->thrtsklet
);
619 if (bcm_rx_thr_flush(op
, 0)) {
620 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
621 return HRTIMER_RESTART
;
623 /* rearm throttle handling */
624 op
->kt_lastmsg
= ktime_set(0, 0);
625 return HRTIMER_NORESTART
;
630 * bcm_rx_handler - handle a CAN frame receiption
632 static void bcm_rx_handler(struct sk_buff
*skb
, void *data
)
634 struct bcm_op
*op
= (struct bcm_op
*)data
;
635 const struct can_frame
*rxframe
= (struct can_frame
*)skb
->data
;
638 /* disable timeout */
639 hrtimer_cancel(&op
->timer
);
641 if (op
->can_id
!= rxframe
->can_id
)
644 /* save rx timestamp */
645 op
->rx_stamp
= skb
->tstamp
;
646 /* save originator for recvfrom() */
647 op
->rx_ifindex
= skb
->dev
->ifindex
;
648 /* update statistics */
651 if (op
->flags
& RX_RTR_FRAME
) {
652 /* send reply for RTR-request (placed in op->frames[0]) */
657 if (op
->flags
& RX_FILTER_ID
) {
658 /* the easiest case */
659 bcm_rx_update_and_send(op
, &op
->last_frames
[0], rxframe
);
663 if (op
->nframes
== 1) {
664 /* simple compare with index 0 */
665 bcm_rx_cmp_to_index(op
, 0, rxframe
);
669 if (op
->nframes
> 1) {
673 * find the first multiplex mask that fits.
674 * Remark: The MUX-mask is stored in index 0
677 for (i
= 1; i
< op
->nframes
; i
++) {
678 if ((GET_U64(&op
->frames
[0]) & GET_U64(rxframe
)) ==
679 (GET_U64(&op
->frames
[0]) &
680 GET_U64(&op
->frames
[i
]))) {
681 bcm_rx_cmp_to_index(op
, i
, rxframe
);
688 bcm_rx_starttimer(op
);
692 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
694 static struct bcm_op
*bcm_find_op(struct list_head
*ops
, canid_t can_id
,
699 list_for_each_entry(op
, ops
, list
) {
700 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
))
707 static void bcm_remove_op(struct bcm_op
*op
)
709 if (op
->tsklet
.func
) {
710 while (test_bit(TASKLET_STATE_SCHED
, &op
->tsklet
.state
) ||
711 test_bit(TASKLET_STATE_RUN
, &op
->tsklet
.state
) ||
712 hrtimer_active(&op
->timer
)) {
713 hrtimer_cancel(&op
->timer
);
714 tasklet_kill(&op
->tsklet
);
718 if (op
->thrtsklet
.func
) {
719 while (test_bit(TASKLET_STATE_SCHED
, &op
->thrtsklet
.state
) ||
720 test_bit(TASKLET_STATE_RUN
, &op
->thrtsklet
.state
) ||
721 hrtimer_active(&op
->thrtimer
)) {
722 hrtimer_cancel(&op
->thrtimer
);
723 tasklet_kill(&op
->thrtsklet
);
727 if ((op
->frames
) && (op
->frames
!= &op
->sframe
))
730 if ((op
->last_frames
) && (op
->last_frames
!= &op
->last_sframe
))
731 kfree(op
->last_frames
);
736 static void bcm_rx_unreg(struct net_device
*dev
, struct bcm_op
*op
)
738 if (op
->rx_reg_dev
== dev
) {
739 can_rx_unregister(dev
, op
->can_id
, REGMASK(op
->can_id
),
742 /* mark as removed subscription */
743 op
->rx_reg_dev
= NULL
;
745 printk(KERN_ERR
"can-bcm: bcm_rx_unreg: registered device "
746 "mismatch %p %p\n", op
->rx_reg_dev
, dev
);
750 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
752 static int bcm_delete_rx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
754 struct bcm_op
*op
, *n
;
756 list_for_each_entry_safe(op
, n
, ops
, list
) {
757 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
760 * Don't care if we're bound or not (due to netdev
761 * problems) can_rx_unregister() is always a save
766 * Only remove subscriptions that had not
767 * been removed due to NETDEV_UNREGISTER
770 if (op
->rx_reg_dev
) {
771 struct net_device
*dev
;
773 dev
= dev_get_by_index(&init_net
,
776 bcm_rx_unreg(dev
, op
);
781 can_rx_unregister(NULL
, op
->can_id
,
791 return 0; /* not found */
795 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
797 static int bcm_delete_tx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
799 struct bcm_op
*op
, *n
;
801 list_for_each_entry_safe(op
, n
, ops
, list
) {
802 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
809 return 0; /* not found */
813 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
815 static int bcm_read_op(struct list_head
*ops
, struct bcm_msg_head
*msg_head
,
818 struct bcm_op
*op
= bcm_find_op(ops
, msg_head
->can_id
, ifindex
);
823 /* put current values into msg_head */
824 msg_head
->flags
= op
->flags
;
825 msg_head
->count
= op
->count
;
826 msg_head
->ival1
= op
->ival1
;
827 msg_head
->ival2
= op
->ival2
;
828 msg_head
->nframes
= op
->nframes
;
830 bcm_send_to_user(op
, msg_head
, op
->frames
, 0);
836 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
838 static int bcm_tx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
839 int ifindex
, struct sock
*sk
)
841 struct bcm_sock
*bo
= bcm_sk(sk
);
846 /* we need a real device to send frames */
850 /* check nframes boundaries - we need at least one can_frame */
851 if (msg_head
->nframes
< 1 || msg_head
->nframes
> MAX_NFRAMES
)
854 /* check the given can_id */
855 op
= bcm_find_op(&bo
->tx_ops
, msg_head
->can_id
, ifindex
);
858 /* update existing BCM operation */
861 * Do we need more space for the can_frames than currently
862 * allocated? -> This is a _really_ unusual use-case and
863 * therefore (complexity / locking) it is not supported.
865 if (msg_head
->nframes
> op
->nframes
)
868 /* update can_frames content */
869 for (i
= 0; i
< msg_head
->nframes
; i
++) {
870 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
871 msg
->msg_iov
, CFSIZ
);
873 if (op
->frames
[i
].can_dlc
> 8)
879 if (msg_head
->flags
& TX_CP_CAN_ID
) {
880 /* copy can_id into frame */
881 op
->frames
[i
].can_id
= msg_head
->can_id
;
886 /* insert new BCM operation for the given can_id */
888 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
892 op
->can_id
= msg_head
->can_id
;
894 /* create array for can_frames and copy the data */
895 if (msg_head
->nframes
> 1) {
896 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
903 op
->frames
= &op
->sframe
;
905 for (i
= 0; i
< msg_head
->nframes
; i
++) {
906 err
= memcpy_fromiovec((u8
*)&op
->frames
[i
],
907 msg
->msg_iov
, CFSIZ
);
909 if (op
->frames
[i
].can_dlc
> 8)
913 if (op
->frames
!= &op
->sframe
)
919 if (msg_head
->flags
& TX_CP_CAN_ID
) {
920 /* copy can_id into frame */
921 op
->frames
[i
].can_id
= msg_head
->can_id
;
925 /* tx_ops never compare with previous received messages */
926 op
->last_frames
= NULL
;
928 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
930 op
->ifindex
= ifindex
;
932 /* initialize uninitialized (kzalloc) structure */
933 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
934 op
->timer
.function
= bcm_tx_timeout_handler
;
936 /* initialize tasklet for tx countevent notification */
937 tasklet_init(&op
->tsklet
, bcm_tx_timeout_tsklet
,
940 /* currently unused in tx_ops */
941 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
943 /* add this bcm_op to the list of the tx_ops */
944 list_add(&op
->list
, &bo
->tx_ops
);
946 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */
948 if (op
->nframes
!= msg_head
->nframes
) {
949 op
->nframes
= msg_head
->nframes
;
950 /* start multiple frame transmission with index 0 */
956 op
->flags
= msg_head
->flags
;
958 if (op
->flags
& TX_RESET_MULTI_IDX
) {
959 /* start multiple frame transmission with index 0 */
963 if (op
->flags
& SETTIMER
) {
964 /* set timer values */
965 op
->count
= msg_head
->count
;
966 op
->ival1
= msg_head
->ival1
;
967 op
->ival2
= msg_head
->ival2
;
968 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
969 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
971 /* disable an active timer due to zero values? */
972 if (!op
->kt_ival1
.tv64
&& !op
->kt_ival2
.tv64
)
973 hrtimer_cancel(&op
->timer
);
976 if (op
->flags
& STARTTIMER
) {
977 hrtimer_cancel(&op
->timer
);
978 /* spec: send can_frame when starting timer */
979 op
->flags
|= TX_ANNOUNCE
;
982 if (op
->flags
& TX_ANNOUNCE
) {
988 if (op
->flags
& STARTTIMER
)
989 bcm_tx_start_timer(op
);
991 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
995 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
997 static int bcm_rx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
998 int ifindex
, struct sock
*sk
)
1000 struct bcm_sock
*bo
= bcm_sk(sk
);
1005 if ((msg_head
->flags
& RX_FILTER_ID
) || (!(msg_head
->nframes
))) {
1006 /* be robust against wrong usage ... */
1007 msg_head
->flags
|= RX_FILTER_ID
;
1008 /* ignore trailing garbage */
1009 msg_head
->nframes
= 0;
1012 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1013 if (msg_head
->nframes
> MAX_NFRAMES
+ 1)
1016 if ((msg_head
->flags
& RX_RTR_FRAME
) &&
1017 ((msg_head
->nframes
!= 1) ||
1018 (!(msg_head
->can_id
& CAN_RTR_FLAG
))))
1021 /* check the given can_id */
1022 op
= bcm_find_op(&bo
->rx_ops
, msg_head
->can_id
, ifindex
);
1024 /* update existing BCM operation */
1027 * Do we need more space for the can_frames than currently
1028 * allocated? -> This is a _really_ unusual use-case and
1029 * therefore (complexity / locking) it is not supported.
1031 if (msg_head
->nframes
> op
->nframes
)
1034 if (msg_head
->nframes
) {
1035 /* update can_frames content */
1036 err
= memcpy_fromiovec((u8
*)op
->frames
,
1038 msg_head
->nframes
* CFSIZ
);
1042 /* clear last_frames to indicate 'nothing received' */
1043 memset(op
->last_frames
, 0, msg_head
->nframes
* CFSIZ
);
1046 op
->nframes
= msg_head
->nframes
;
1048 /* Only an update -> do not call can_rx_register() */
1052 /* insert new BCM operation for the given can_id */
1053 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
1057 op
->can_id
= msg_head
->can_id
;
1058 op
->nframes
= msg_head
->nframes
;
1060 if (msg_head
->nframes
> 1) {
1061 /* create array for can_frames and copy the data */
1062 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
1069 /* create and init array for received can_frames */
1070 op
->last_frames
= kzalloc(msg_head
->nframes
* CFSIZ
,
1072 if (!op
->last_frames
) {
1079 op
->frames
= &op
->sframe
;
1080 op
->last_frames
= &op
->last_sframe
;
1083 if (msg_head
->nframes
) {
1084 err
= memcpy_fromiovec((u8
*)op
->frames
, msg
->msg_iov
,
1085 msg_head
->nframes
* CFSIZ
);
1087 if (op
->frames
!= &op
->sframe
)
1089 if (op
->last_frames
!= &op
->last_sframe
)
1090 kfree(op
->last_frames
);
1096 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1098 op
->ifindex
= ifindex
;
1100 /* ifindex for timeout events w/o previous frame reception */
1101 op
->rx_ifindex
= ifindex
;
1103 /* initialize uninitialized (kzalloc) structure */
1104 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1105 op
->timer
.function
= bcm_rx_timeout_handler
;
1107 /* initialize tasklet for rx timeout notification */
1108 tasklet_init(&op
->tsklet
, bcm_rx_timeout_tsklet
,
1109 (unsigned long) op
);
1111 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1112 op
->thrtimer
.function
= bcm_rx_thr_handler
;
1114 /* initialize tasklet for rx throttle handling */
1115 tasklet_init(&op
->thrtsklet
, bcm_rx_thr_tsklet
,
1116 (unsigned long) op
);
1118 /* add this bcm_op to the list of the rx_ops */
1119 list_add(&op
->list
, &bo
->rx_ops
);
1121 /* call can_rx_register() */
1124 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1127 op
->flags
= msg_head
->flags
;
1129 if (op
->flags
& RX_RTR_FRAME
) {
1131 /* no timers in RTR-mode */
1132 hrtimer_cancel(&op
->thrtimer
);
1133 hrtimer_cancel(&op
->timer
);
1136 * funny feature in RX(!)_SETUP only for RTR-mode:
1137 * copy can_id into frame BUT without RTR-flag to
1138 * prevent a full-load-loopback-test ... ;-]
1140 if ((op
->flags
& TX_CP_CAN_ID
) ||
1141 (op
->frames
[0].can_id
== op
->can_id
))
1142 op
->frames
[0].can_id
= op
->can_id
& ~CAN_RTR_FLAG
;
1145 if (op
->flags
& SETTIMER
) {
1147 /* set timer value */
1148 op
->ival1
= msg_head
->ival1
;
1149 op
->ival2
= msg_head
->ival2
;
1150 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
1151 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
1153 /* disable an active timer due to zero value? */
1154 if (!op
->kt_ival1
.tv64
)
1155 hrtimer_cancel(&op
->timer
);
1158 * In any case cancel the throttle timer, flush
1159 * potentially blocked msgs and reset throttle handling
1161 op
->kt_lastmsg
= ktime_set(0, 0);
1162 hrtimer_cancel(&op
->thrtimer
);
1163 bcm_rx_thr_flush(op
, 1);
1166 if ((op
->flags
& STARTTIMER
) && op
->kt_ival1
.tv64
)
1167 hrtimer_start(&op
->timer
, op
->kt_ival1
,
1171 /* now we can register for can_ids, if we added a new bcm_op */
1172 if (do_rx_register
) {
1174 struct net_device
*dev
;
1176 dev
= dev_get_by_index(&init_net
, ifindex
);
1178 err
= can_rx_register(dev
, op
->can_id
,
1179 REGMASK(op
->can_id
),
1183 op
->rx_reg_dev
= dev
;
1188 err
= can_rx_register(NULL
, op
->can_id
,
1189 REGMASK(op
->can_id
),
1190 bcm_rx_handler
, op
, "bcm", sk
);
1192 /* this bcm rx op is broken -> remove it */
1193 list_del(&op
->list
);
1199 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
1203 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1205 static int bcm_tx_send(struct msghdr
*msg
, int ifindex
, struct sock
*sk
)
1207 struct sk_buff
*skb
;
1208 struct net_device
*dev
;
1211 /* we need a real device to send frames */
1215 skb
= alloc_skb(CFSIZ
+ sizeof(struct can_skb_priv
), GFP_KERNEL
);
1219 can_skb_reserve(skb
);
1221 err
= memcpy_fromiovec(skb_put(skb
, CFSIZ
), msg
->msg_iov
, CFSIZ
);
1227 dev
= dev_get_by_index(&init_net
, ifindex
);
1233 can_skb_prv(skb
)->ifindex
= dev
->ifindex
;
1235 can_skb_set_owner(skb
, sk
);
1236 err
= can_send(skb
, 1); /* send with loopback */
1242 return CFSIZ
+ MHSIZ
;
1246 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1248 static int bcm_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1249 struct msghdr
*msg
, size_t size
)
1251 struct sock
*sk
= sock
->sk
;
1252 struct bcm_sock
*bo
= bcm_sk(sk
);
1253 int ifindex
= bo
->ifindex
; /* default ifindex for this bcm_op */
1254 struct bcm_msg_head msg_head
;
1255 int ret
; /* read bytes or error codes as return value */
1260 /* check for valid message length from userspace */
1261 if (size
< MHSIZ
|| (size
- MHSIZ
) % CFSIZ
)
1264 /* check for alternative ifindex for this bcm_op */
1266 if (!ifindex
&& msg
->msg_name
) {
1267 /* no bound device as default => check msg_name */
1268 struct sockaddr_can
*addr
=
1269 (struct sockaddr_can
*)msg
->msg_name
;
1271 if (msg
->msg_namelen
< sizeof(*addr
))
1274 if (addr
->can_family
!= AF_CAN
)
1277 /* ifindex from sendto() */
1278 ifindex
= addr
->can_ifindex
;
1281 struct net_device
*dev
;
1283 dev
= dev_get_by_index(&init_net
, ifindex
);
1287 if (dev
->type
!= ARPHRD_CAN
) {
1296 /* read message head information */
1298 ret
= memcpy_fromiovec((u8
*)&msg_head
, msg
->msg_iov
, MHSIZ
);
1304 switch (msg_head
.opcode
) {
1307 ret
= bcm_tx_setup(&msg_head
, msg
, ifindex
, sk
);
1311 ret
= bcm_rx_setup(&msg_head
, msg
, ifindex
, sk
);
1315 if (bcm_delete_tx_op(&bo
->tx_ops
, msg_head
.can_id
, ifindex
))
1322 if (bcm_delete_rx_op(&bo
->rx_ops
, msg_head
.can_id
, ifindex
))
1329 /* reuse msg_head for the reply to TX_READ */
1330 msg_head
.opcode
= TX_STATUS
;
1331 ret
= bcm_read_op(&bo
->tx_ops
, &msg_head
, ifindex
);
1335 /* reuse msg_head for the reply to RX_READ */
1336 msg_head
.opcode
= RX_STATUS
;
1337 ret
= bcm_read_op(&bo
->rx_ops
, &msg_head
, ifindex
);
1341 /* we need exactly one can_frame behind the msg head */
1342 if ((msg_head
.nframes
!= 1) || (size
!= CFSIZ
+ MHSIZ
))
1345 ret
= bcm_tx_send(msg
, ifindex
, sk
);
1359 * notification handler for netdevice status changes
1361 static int bcm_notifier(struct notifier_block
*nb
, unsigned long msg
,
1364 struct net_device
*dev
= (struct net_device
*)data
;
1365 struct bcm_sock
*bo
= container_of(nb
, struct bcm_sock
, notifier
);
1366 struct sock
*sk
= &bo
->sk
;
1368 int notify_enodev
= 0;
1370 if (!net_eq(dev_net(dev
), &init_net
))
1373 if (dev
->type
!= ARPHRD_CAN
)
1378 case NETDEV_UNREGISTER
:
1381 /* remove device specific receive entries */
1382 list_for_each_entry(op
, &bo
->rx_ops
, list
)
1383 if (op
->rx_reg_dev
== dev
)
1384 bcm_rx_unreg(dev
, op
);
1386 /* remove device reference, if this is our bound device */
1387 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1395 if (notify_enodev
) {
1396 sk
->sk_err
= ENODEV
;
1397 if (!sock_flag(sk
, SOCK_DEAD
))
1398 sk
->sk_error_report(sk
);
1403 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1404 sk
->sk_err
= ENETDOWN
;
1405 if (!sock_flag(sk
, SOCK_DEAD
))
1406 sk
->sk_error_report(sk
);
1414 * initial settings for all BCM sockets to be set at socket creation time
1416 static int bcm_init(struct sock
*sk
)
1418 struct bcm_sock
*bo
= bcm_sk(sk
);
1422 bo
->dropped_usr_msgs
= 0;
1423 bo
->bcm_proc_read
= NULL
;
1425 INIT_LIST_HEAD(&bo
->tx_ops
);
1426 INIT_LIST_HEAD(&bo
->rx_ops
);
1429 bo
->notifier
.notifier_call
= bcm_notifier
;
1431 register_netdevice_notifier(&bo
->notifier
);
1437 * standard socket functions
1439 static int bcm_release(struct socket
*sock
)
1441 struct sock
*sk
= sock
->sk
;
1442 struct bcm_sock
*bo
;
1443 struct bcm_op
*op
, *next
;
1450 /* remove bcm_ops, timer, rx_unregister(), etc. */
1452 unregister_netdevice_notifier(&bo
->notifier
);
1456 list_for_each_entry_safe(op
, next
, &bo
->tx_ops
, list
)
1459 list_for_each_entry_safe(op
, next
, &bo
->rx_ops
, list
) {
1461 * Don't care if we're bound or not (due to netdev problems)
1462 * can_rx_unregister() is always a save thing to do here.
1466 * Only remove subscriptions that had not
1467 * been removed due to NETDEV_UNREGISTER
1470 if (op
->rx_reg_dev
) {
1471 struct net_device
*dev
;
1473 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
1475 bcm_rx_unreg(dev
, op
);
1480 can_rx_unregister(NULL
, op
->can_id
,
1481 REGMASK(op
->can_id
),
1482 bcm_rx_handler
, op
);
1487 /* remove procfs entry */
1488 if (proc_dir
&& bo
->bcm_proc_read
)
1489 remove_proc_entry(bo
->procname
, proc_dir
);
1491 /* remove device reference */
1506 static int bcm_connect(struct socket
*sock
, struct sockaddr
*uaddr
, int len
,
1509 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
1510 struct sock
*sk
= sock
->sk
;
1511 struct bcm_sock
*bo
= bcm_sk(sk
);
1514 if (len
< sizeof(*addr
))
1524 /* bind a device to this socket */
1525 if (addr
->can_ifindex
) {
1526 struct net_device
*dev
;
1528 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
1533 if (dev
->type
!= ARPHRD_CAN
) {
1539 bo
->ifindex
= dev
->ifindex
;
1543 /* no interface reference for ifindex = 0 ('any' CAN device) */
1548 /* unique socket address as filename */
1549 sprintf(bo
->procname
, "%lu", sock_i_ino(sk
));
1550 bo
->bcm_proc_read
= proc_create_data(bo
->procname
, 0644,
1552 &bcm_proc_fops
, sk
);
1553 if (!bo
->bcm_proc_read
) {
1567 static int bcm_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1568 struct msghdr
*msg
, size_t size
, int flags
)
1570 struct sock
*sk
= sock
->sk
;
1571 struct sk_buff
*skb
;
1576 noblock
= flags
& MSG_DONTWAIT
;
1577 flags
&= ~MSG_DONTWAIT
;
1578 skb
= skb_recv_datagram(sk
, flags
, noblock
, &error
);
1582 if (skb
->len
< size
)
1585 err
= memcpy_toiovec(msg
->msg_iov
, skb
->data
, size
);
1587 skb_free_datagram(sk
, skb
);
1591 sock_recv_ts_and_drops(msg
, sk
, skb
);
1593 if (msg
->msg_name
) {
1594 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
1595 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
1598 skb_free_datagram(sk
, skb
);
1603 static const struct proto_ops bcm_ops
= {
1605 .release
= bcm_release
,
1606 .bind
= sock_no_bind
,
1607 .connect
= bcm_connect
,
1608 .socketpair
= sock_no_socketpair
,
1609 .accept
= sock_no_accept
,
1610 .getname
= sock_no_getname
,
1611 .poll
= datagram_poll
,
1612 .ioctl
= can_ioctl
, /* use can_ioctl() from af_can.c */
1613 .listen
= sock_no_listen
,
1614 .shutdown
= sock_no_shutdown
,
1615 .setsockopt
= sock_no_setsockopt
,
1616 .getsockopt
= sock_no_getsockopt
,
1617 .sendmsg
= bcm_sendmsg
,
1618 .recvmsg
= bcm_recvmsg
,
1619 .mmap
= sock_no_mmap
,
1620 .sendpage
= sock_no_sendpage
,
1623 static struct proto bcm_proto __read_mostly
= {
1625 .owner
= THIS_MODULE
,
1626 .obj_size
= sizeof(struct bcm_sock
),
1630 static const struct can_proto bcm_can_proto
= {
1632 .protocol
= CAN_BCM
,
1637 static int __init
bcm_module_init(void)
1643 err
= can_proto_register(&bcm_can_proto
);
1645 printk(KERN_ERR
"can: registration of bcm protocol failed\n");
1649 /* create /proc/net/can-bcm directory */
1650 proc_dir
= proc_mkdir("can-bcm", init_net
.proc_net
);
1654 static void __exit
bcm_module_exit(void)
1656 can_proto_unregister(&bcm_can_proto
);
1659 remove_proc_entry("can-bcm", init_net
.proc_net
);
1662 module_init(bcm_module_init
);
1663 module_exit(bcm_module_exit
);