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
82 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol");
83 MODULE_LICENSE("Dual BSD/GPL");
84 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
85 MODULE_ALIAS("can-proto-2");
87 /* easy access to can_frame payload */
88 static inline u64
GET_U64(const struct can_frame
*cp
)
90 return *(u64
*)cp
->data
;
94 struct list_head list
;
98 unsigned long frames_abs
, frames_filtered
;
99 struct timeval ival1
, ival2
;
100 struct hrtimer timer
, thrtimer
;
101 struct tasklet_struct tsklet
, thrtsklet
;
102 ktime_t rx_stamp
, kt_ival1
, kt_ival2
, kt_lastmsg
;
107 struct can_frame
*frames
;
108 struct can_frame
*last_frames
;
109 struct can_frame sframe
;
110 struct can_frame last_sframe
;
112 struct net_device
*rx_reg_dev
;
115 static struct proc_dir_entry
*proc_dir
;
121 struct notifier_block notifier
;
122 struct list_head rx_ops
;
123 struct list_head tx_ops
;
124 unsigned long dropped_usr_msgs
;
125 struct proc_dir_entry
*bcm_proc_read
;
126 char procname
[32]; /* inode number in decimal with \0 */
129 static inline struct bcm_sock
*bcm_sk(const struct sock
*sk
)
131 return (struct bcm_sock
*)sk
;
134 #define CFSIZ sizeof(struct can_frame)
135 #define OPSIZ sizeof(struct bcm_op)
136 #define MHSIZ sizeof(struct bcm_msg_head)
141 static char *bcm_proc_getifname(char *result
, int ifindex
)
143 struct net_device
*dev
;
149 dev
= dev_get_by_index_rcu(&init_net
, ifindex
);
151 strcpy(result
, dev
->name
);
153 strcpy(result
, "???");
159 static int bcm_proc_show(struct seq_file
*m
, void *v
)
161 char ifname
[IFNAMSIZ
];
162 struct sock
*sk
= (struct sock
*)m
->private;
163 struct bcm_sock
*bo
= bcm_sk(sk
);
166 seq_printf(m
, ">>> socket %pK", sk
->sk_socket
);
167 seq_printf(m
, " / sk %pK", sk
);
168 seq_printf(m
, " / bo %pK", bo
);
169 seq_printf(m
, " / dropped %lu", bo
->dropped_usr_msgs
);
170 seq_printf(m
, " / bound %s", bcm_proc_getifname(ifname
, bo
->ifindex
));
171 seq_printf(m
, " <<<\n");
173 list_for_each_entry(op
, &bo
->rx_ops
, list
) {
175 unsigned long reduction
;
177 /* print only active entries & prevent division by zero */
181 seq_printf(m
, "rx_op: %03X %-5s ",
182 op
->can_id
, bcm_proc_getifname(ifname
, op
->ifindex
));
183 seq_printf(m
, "[%u]%c ", op
->nframes
,
184 (op
->flags
& RX_CHECK_DLC
)?'d':' ');
185 if (op
->kt_ival1
.tv64
)
186 seq_printf(m
, "timeo=%lld ",
188 ktime_to_us(op
->kt_ival1
));
190 if (op
->kt_ival2
.tv64
)
191 seq_printf(m
, "thr=%lld ",
193 ktime_to_us(op
->kt_ival2
));
195 seq_printf(m
, "# recv %ld (%ld) => reduction: ",
196 op
->frames_filtered
, op
->frames_abs
);
198 reduction
= 100 - (op
->frames_filtered
* 100) / op
->frames_abs
;
200 seq_printf(m
, "%s%ld%%\n",
201 (reduction
== 100)?"near ":"", reduction
);
204 list_for_each_entry(op
, &bo
->tx_ops
, list
) {
206 seq_printf(m
, "tx_op: %03X %s [%u] ",
208 bcm_proc_getifname(ifname
, op
->ifindex
),
211 if (op
->kt_ival1
.tv64
)
212 seq_printf(m
, "t1=%lld ",
213 (long long) ktime_to_us(op
->kt_ival1
));
215 if (op
->kt_ival2
.tv64
)
216 seq_printf(m
, "t2=%lld ",
217 (long long) ktime_to_us(op
->kt_ival2
));
219 seq_printf(m
, "# sent %ld\n", op
->frames_abs
);
225 static int bcm_proc_open(struct inode
*inode
, struct file
*file
)
227 return single_open(file
, bcm_proc_show
, PDE_DATA(inode
));
230 static const struct file_operations bcm_proc_fops
= {
231 .owner
= THIS_MODULE
,
232 .open
= bcm_proc_open
,
235 .release
= single_release
,
239 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface
240 * of the given bcm tx op
242 static void bcm_can_tx(struct bcm_op
*op
)
245 struct net_device
*dev
;
246 struct can_frame
*cf
= &op
->frames
[op
->currframe
];
248 /* no target device? => exit */
252 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
254 /* RFC: should this bcm_op remove itself here? */
258 skb
= alloc_skb(CFSIZ
+ sizeof(struct can_skb_priv
), gfp_any());
262 can_skb_reserve(skb
);
263 can_skb_prv(skb
)->ifindex
= dev
->ifindex
;
265 memcpy(skb_put(skb
, CFSIZ
), cf
, CFSIZ
);
267 /* send with loopback */
269 can_skb_set_owner(skb
, op
->sk
);
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_start_timer(struct bcm_op
*op
)
349 if (op
->kt_ival1
.tv64
&& op
->count
)
350 hrtimer_start(&op
->timer
,
351 ktime_add(ktime_get(), op
->kt_ival1
),
353 else if (op
->kt_ival2
.tv64
)
354 hrtimer_start(&op
->timer
,
355 ktime_add(ktime_get(), op
->kt_ival2
),
359 static void bcm_tx_timeout_tsklet(unsigned long data
)
361 struct bcm_op
*op
= (struct bcm_op
*)data
;
362 struct bcm_msg_head msg_head
;
364 if (op
->kt_ival1
.tv64
&& (op
->count
> 0)) {
367 if (!op
->count
&& (op
->flags
& TX_COUNTEVT
)) {
369 /* create notification to user */
370 msg_head
.opcode
= TX_EXPIRED
;
371 msg_head
.flags
= op
->flags
;
372 msg_head
.count
= op
->count
;
373 msg_head
.ival1
= op
->ival1
;
374 msg_head
.ival2
= op
->ival2
;
375 msg_head
.can_id
= op
->can_id
;
376 msg_head
.nframes
= 0;
378 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
382 } else if (op
->kt_ival2
.tv64
)
385 bcm_tx_start_timer(op
);
389 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions
391 static enum hrtimer_restart
bcm_tx_timeout_handler(struct hrtimer
*hrtimer
)
393 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
395 tasklet_schedule(&op
->tsklet
);
397 return HRTIMER_NORESTART
;
401 * bcm_rx_changed - create a RX_CHANGED notification due to changed content
403 static void bcm_rx_changed(struct bcm_op
*op
, struct can_frame
*data
)
405 struct bcm_msg_head head
;
407 /* update statistics */
408 op
->frames_filtered
++;
410 /* prevent statistics overflow */
411 if (op
->frames_filtered
> ULONG_MAX
/100)
412 op
->frames_filtered
= op
->frames_abs
= 0;
414 /* this element is not throttled anymore */
415 data
->can_dlc
&= (BCM_CAN_DLC_MASK
|RX_RECV
);
417 head
.opcode
= RX_CHANGED
;
418 head
.flags
= op
->flags
;
419 head
.count
= op
->count
;
420 head
.ival1
= op
->ival1
;
421 head
.ival2
= op
->ival2
;
422 head
.can_id
= op
->can_id
;
425 bcm_send_to_user(op
, &head
, data
, 1);
429 * bcm_rx_update_and_send - process a detected relevant receive content change
430 * 1. update the last received data
431 * 2. send a notification to the user (if possible)
433 static void bcm_rx_update_and_send(struct bcm_op
*op
,
434 struct can_frame
*lastdata
,
435 const struct can_frame
*rxdata
)
437 memcpy(lastdata
, rxdata
, CFSIZ
);
439 /* mark as used and throttled by default */
440 lastdata
->can_dlc
|= (RX_RECV
|RX_THR
);
442 /* throttling mode inactive ? */
443 if (!op
->kt_ival2
.tv64
) {
444 /* send RX_CHANGED to the user immediately */
445 bcm_rx_changed(op
, lastdata
);
449 /* with active throttling timer we are just done here */
450 if (hrtimer_active(&op
->thrtimer
))
453 /* first reception with enabled throttling mode */
454 if (!op
->kt_lastmsg
.tv64
)
455 goto rx_changed_settime
;
457 /* got a second frame inside a potential throttle period? */
458 if (ktime_us_delta(ktime_get(), op
->kt_lastmsg
) <
459 ktime_to_us(op
->kt_ival2
)) {
460 /* do not send the saved data - only start throttle timer */
461 hrtimer_start(&op
->thrtimer
,
462 ktime_add(op
->kt_lastmsg
, op
->kt_ival2
),
467 /* the gap was that big, that throttling was not needed here */
469 bcm_rx_changed(op
, lastdata
);
470 op
->kt_lastmsg
= ktime_get();
474 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly
475 * received data stored in op->last_frames[]
477 static void bcm_rx_cmp_to_index(struct bcm_op
*op
, unsigned int index
,
478 const struct can_frame
*rxdata
)
481 * no one uses the MSBs of can_dlc for comparison,
482 * so we use it here to detect the first time of reception
485 if (!(op
->last_frames
[index
].can_dlc
& RX_RECV
)) {
486 /* received data for the first time => send update to user */
487 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
491 /* do a real check in can_frame data section */
493 if ((GET_U64(&op
->frames
[index
]) & GET_U64(rxdata
)) !=
494 (GET_U64(&op
->frames
[index
]) & GET_U64(&op
->last_frames
[index
]))) {
495 bcm_rx_update_and_send(op
, &op
->last_frames
[index
], rxdata
);
499 if (op
->flags
& RX_CHECK_DLC
) {
500 /* do a real check in can_frame dlc */
501 if (rxdata
->can_dlc
!= (op
->last_frames
[index
].can_dlc
&
503 bcm_rx_update_and_send(op
, &op
->last_frames
[index
],
511 * bcm_rx_starttimer - enable timeout monitoring for CAN frame reception
513 static void bcm_rx_starttimer(struct bcm_op
*op
)
515 if (op
->flags
& RX_NO_AUTOTIMER
)
518 if (op
->kt_ival1
.tv64
)
519 hrtimer_start(&op
->timer
, op
->kt_ival1
, HRTIMER_MODE_REL
);
522 static void bcm_rx_timeout_tsklet(unsigned long data
)
524 struct bcm_op
*op
= (struct bcm_op
*)data
;
525 struct bcm_msg_head msg_head
;
527 /* create notification to user */
528 msg_head
.opcode
= RX_TIMEOUT
;
529 msg_head
.flags
= op
->flags
;
530 msg_head
.count
= op
->count
;
531 msg_head
.ival1
= op
->ival1
;
532 msg_head
.ival2
= op
->ival2
;
533 msg_head
.can_id
= op
->can_id
;
534 msg_head
.nframes
= 0;
536 bcm_send_to_user(op
, &msg_head
, NULL
, 0);
540 * bcm_rx_timeout_handler - when the (cyclic) CAN frame reception timed out
542 static enum hrtimer_restart
bcm_rx_timeout_handler(struct hrtimer
*hrtimer
)
544 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, timer
);
546 /* schedule before NET_RX_SOFTIRQ */
547 tasklet_hi_schedule(&op
->tsklet
);
549 /* no restart of the timer is done here! */
551 /* if user wants to be informed, when cyclic CAN-Messages come back */
552 if ((op
->flags
& RX_ANNOUNCE_RESUME
) && op
->last_frames
) {
553 /* clear received can_frames to indicate 'nothing received' */
554 memset(op
->last_frames
, 0, op
->nframes
* CFSIZ
);
557 return HRTIMER_NORESTART
;
561 * bcm_rx_do_flush - helper for bcm_rx_thr_flush
563 static inline int bcm_rx_do_flush(struct bcm_op
*op
, int update
,
566 if ((op
->last_frames
) && (op
->last_frames
[index
].can_dlc
& RX_THR
)) {
568 bcm_rx_changed(op
, &op
->last_frames
[index
]);
575 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace
577 * update == 0 : just check if throttled data is available (any irq context)
578 * update == 1 : check and send throttled data to userspace (soft_irq context)
580 static int bcm_rx_thr_flush(struct bcm_op
*op
, int update
)
584 if (op
->nframes
> 1) {
587 /* for MUX filter we start at index 1 */
588 for (i
= 1; i
< op
->nframes
; i
++)
589 updated
+= bcm_rx_do_flush(op
, update
, i
);
592 /* for RX_FILTER_ID and simple filter */
593 updated
+= bcm_rx_do_flush(op
, update
, 0);
599 static void bcm_rx_thr_tsklet(unsigned long data
)
601 struct bcm_op
*op
= (struct bcm_op
*)data
;
603 /* push the changed data to the userspace */
604 bcm_rx_thr_flush(op
, 1);
608 * bcm_rx_thr_handler - the time for blocked content updates is over now:
609 * Check for throttled data and send it to the userspace
611 static enum hrtimer_restart
bcm_rx_thr_handler(struct hrtimer
*hrtimer
)
613 struct bcm_op
*op
= container_of(hrtimer
, struct bcm_op
, thrtimer
);
615 tasklet_schedule(&op
->thrtsklet
);
617 if (bcm_rx_thr_flush(op
, 0)) {
618 hrtimer_forward(hrtimer
, ktime_get(), op
->kt_ival2
);
619 return HRTIMER_RESTART
;
621 /* rearm throttle handling */
622 op
->kt_lastmsg
= ktime_set(0, 0);
623 return HRTIMER_NORESTART
;
628 * bcm_rx_handler - handle a CAN frame reception
630 static void bcm_rx_handler(struct sk_buff
*skb
, void *data
)
632 struct bcm_op
*op
= (struct bcm_op
*)data
;
633 const struct can_frame
*rxframe
= (struct can_frame
*)skb
->data
;
636 /* disable timeout */
637 hrtimer_cancel(&op
->timer
);
639 if (op
->can_id
!= rxframe
->can_id
)
642 /* save rx timestamp */
643 op
->rx_stamp
= skb
->tstamp
;
644 /* save originator for recvfrom() */
645 op
->rx_ifindex
= skb
->dev
->ifindex
;
646 /* update statistics */
649 if (op
->flags
& RX_RTR_FRAME
) {
650 /* send reply for RTR-request (placed in op->frames[0]) */
655 if (op
->flags
& RX_FILTER_ID
) {
656 /* the easiest case */
657 bcm_rx_update_and_send(op
, &op
->last_frames
[0], rxframe
);
661 if (op
->nframes
== 1) {
662 /* simple compare with index 0 */
663 bcm_rx_cmp_to_index(op
, 0, rxframe
);
667 if (op
->nframes
> 1) {
671 * find the first multiplex mask that fits.
672 * Remark: The MUX-mask is stored in index 0
675 for (i
= 1; i
< op
->nframes
; i
++) {
676 if ((GET_U64(&op
->frames
[0]) & GET_U64(rxframe
)) ==
677 (GET_U64(&op
->frames
[0]) &
678 GET_U64(&op
->frames
[i
]))) {
679 bcm_rx_cmp_to_index(op
, i
, rxframe
);
686 bcm_rx_starttimer(op
);
690 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements
692 static struct bcm_op
*bcm_find_op(struct list_head
*ops
, canid_t can_id
,
697 list_for_each_entry(op
, ops
, list
) {
698 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
))
705 static void bcm_remove_op(struct bcm_op
*op
)
707 hrtimer_cancel(&op
->timer
);
708 hrtimer_cancel(&op
->thrtimer
);
711 tasklet_kill(&op
->tsklet
);
713 if (op
->thrtsklet
.func
)
714 tasklet_kill(&op
->thrtsklet
);
716 if ((op
->frames
) && (op
->frames
!= &op
->sframe
))
719 if ((op
->last_frames
) && (op
->last_frames
!= &op
->last_sframe
))
720 kfree(op
->last_frames
);
725 static void bcm_rx_unreg(struct net_device
*dev
, struct bcm_op
*op
)
727 if (op
->rx_reg_dev
== dev
) {
728 can_rx_unregister(dev
, op
->can_id
, REGMASK(op
->can_id
),
731 /* mark as removed subscription */
732 op
->rx_reg_dev
= NULL
;
734 printk(KERN_ERR
"can-bcm: bcm_rx_unreg: registered device "
735 "mismatch %p %p\n", op
->rx_reg_dev
, dev
);
739 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops)
741 static int bcm_delete_rx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
743 struct bcm_op
*op
, *n
;
745 list_for_each_entry_safe(op
, n
, ops
, list
) {
746 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
749 * Don't care if we're bound or not (due to netdev
750 * problems) can_rx_unregister() is always a save
755 * Only remove subscriptions that had not
756 * been removed due to NETDEV_UNREGISTER
759 if (op
->rx_reg_dev
) {
760 struct net_device
*dev
;
762 dev
= dev_get_by_index(&init_net
,
765 bcm_rx_unreg(dev
, op
);
770 can_rx_unregister(NULL
, op
->can_id
,
780 return 0; /* not found */
784 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops)
786 static int bcm_delete_tx_op(struct list_head
*ops
, canid_t can_id
, int ifindex
)
788 struct bcm_op
*op
, *n
;
790 list_for_each_entry_safe(op
, n
, ops
, list
) {
791 if ((op
->can_id
== can_id
) && (op
->ifindex
== ifindex
)) {
798 return 0; /* not found */
802 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg)
804 static int bcm_read_op(struct list_head
*ops
, struct bcm_msg_head
*msg_head
,
807 struct bcm_op
*op
= bcm_find_op(ops
, msg_head
->can_id
, ifindex
);
812 /* put current values into msg_head */
813 msg_head
->flags
= op
->flags
;
814 msg_head
->count
= op
->count
;
815 msg_head
->ival1
= op
->ival1
;
816 msg_head
->ival2
= op
->ival2
;
817 msg_head
->nframes
= op
->nframes
;
819 bcm_send_to_user(op
, msg_head
, op
->frames
, 0);
825 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg)
827 static int bcm_tx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
828 int ifindex
, struct sock
*sk
)
830 struct bcm_sock
*bo
= bcm_sk(sk
);
835 /* we need a real device to send frames */
839 /* check nframes boundaries - we need at least one can_frame */
840 if (msg_head
->nframes
< 1 || msg_head
->nframes
> MAX_NFRAMES
)
843 /* check the given can_id */
844 op
= bcm_find_op(&bo
->tx_ops
, msg_head
->can_id
, ifindex
);
847 /* update existing BCM operation */
850 * Do we need more space for the can_frames than currently
851 * allocated? -> This is a _really_ unusual use-case and
852 * therefore (complexity / locking) it is not supported.
854 if (msg_head
->nframes
> op
->nframes
)
857 /* update can_frames content */
858 for (i
= 0; i
< msg_head
->nframes
; i
++) {
859 err
= memcpy_from_msg((u8
*)&op
->frames
[i
], msg
, 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_from_msg((u8
*)&op
->frames
[i
], msg
, 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 hrtimer_cancel(&op
->timer
);
965 /* spec: send can_frame when starting timer */
966 op
->flags
|= TX_ANNOUNCE
;
969 if (op
->flags
& TX_ANNOUNCE
) {
975 if (op
->flags
& STARTTIMER
)
976 bcm_tx_start_timer(op
);
978 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
982 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg)
984 static int bcm_rx_setup(struct bcm_msg_head
*msg_head
, struct msghdr
*msg
,
985 int ifindex
, struct sock
*sk
)
987 struct bcm_sock
*bo
= bcm_sk(sk
);
992 if ((msg_head
->flags
& RX_FILTER_ID
) || (!(msg_head
->nframes
))) {
993 /* be robust against wrong usage ... */
994 msg_head
->flags
|= RX_FILTER_ID
;
995 /* ignore trailing garbage */
996 msg_head
->nframes
= 0;
999 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */
1000 if (msg_head
->nframes
> MAX_NFRAMES
+ 1)
1003 if ((msg_head
->flags
& RX_RTR_FRAME
) &&
1004 ((msg_head
->nframes
!= 1) ||
1005 (!(msg_head
->can_id
& CAN_RTR_FLAG
))))
1008 /* check the given can_id */
1009 op
= bcm_find_op(&bo
->rx_ops
, msg_head
->can_id
, ifindex
);
1011 /* update existing BCM operation */
1014 * Do we need more space for the can_frames than currently
1015 * allocated? -> This is a _really_ unusual use-case and
1016 * therefore (complexity / locking) it is not supported.
1018 if (msg_head
->nframes
> op
->nframes
)
1021 if (msg_head
->nframes
) {
1022 /* update can_frames content */
1023 err
= memcpy_from_msg((u8
*)op
->frames
, msg
,
1024 msg_head
->nframes
* CFSIZ
);
1028 /* clear last_frames to indicate 'nothing received' */
1029 memset(op
->last_frames
, 0, msg_head
->nframes
* CFSIZ
);
1032 op
->nframes
= msg_head
->nframes
;
1034 /* Only an update -> do not call can_rx_register() */
1038 /* insert new BCM operation for the given can_id */
1039 op
= kzalloc(OPSIZ
, GFP_KERNEL
);
1043 op
->can_id
= msg_head
->can_id
;
1044 op
->nframes
= msg_head
->nframes
;
1046 if (msg_head
->nframes
> 1) {
1047 /* create array for can_frames and copy the data */
1048 op
->frames
= kmalloc(msg_head
->nframes
* CFSIZ
,
1055 /* create and init array for received can_frames */
1056 op
->last_frames
= kzalloc(msg_head
->nframes
* CFSIZ
,
1058 if (!op
->last_frames
) {
1065 op
->frames
= &op
->sframe
;
1066 op
->last_frames
= &op
->last_sframe
;
1069 if (msg_head
->nframes
) {
1070 err
= memcpy_from_msg((u8
*)op
->frames
, msg
,
1071 msg_head
->nframes
* CFSIZ
);
1073 if (op
->frames
!= &op
->sframe
)
1075 if (op
->last_frames
!= &op
->last_sframe
)
1076 kfree(op
->last_frames
);
1082 /* bcm_can_tx / bcm_tx_timeout_handler needs this */
1084 op
->ifindex
= ifindex
;
1086 /* ifindex for timeout events w/o previous frame reception */
1087 op
->rx_ifindex
= ifindex
;
1089 /* initialize uninitialized (kzalloc) structure */
1090 hrtimer_init(&op
->timer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1091 op
->timer
.function
= bcm_rx_timeout_handler
;
1093 /* initialize tasklet for rx timeout notification */
1094 tasklet_init(&op
->tsklet
, bcm_rx_timeout_tsklet
,
1095 (unsigned long) op
);
1097 hrtimer_init(&op
->thrtimer
, CLOCK_MONOTONIC
, HRTIMER_MODE_REL
);
1098 op
->thrtimer
.function
= bcm_rx_thr_handler
;
1100 /* initialize tasklet for rx throttle handling */
1101 tasklet_init(&op
->thrtsklet
, bcm_rx_thr_tsklet
,
1102 (unsigned long) op
);
1104 /* add this bcm_op to the list of the rx_ops */
1105 list_add(&op
->list
, &bo
->rx_ops
);
1107 /* call can_rx_register() */
1110 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */
1113 op
->flags
= msg_head
->flags
;
1115 if (op
->flags
& RX_RTR_FRAME
) {
1117 /* no timers in RTR-mode */
1118 hrtimer_cancel(&op
->thrtimer
);
1119 hrtimer_cancel(&op
->timer
);
1122 * funny feature in RX(!)_SETUP only for RTR-mode:
1123 * copy can_id into frame BUT without RTR-flag to
1124 * prevent a full-load-loopback-test ... ;-]
1126 if ((op
->flags
& TX_CP_CAN_ID
) ||
1127 (op
->frames
[0].can_id
== op
->can_id
))
1128 op
->frames
[0].can_id
= op
->can_id
& ~CAN_RTR_FLAG
;
1131 if (op
->flags
& SETTIMER
) {
1133 /* set timer value */
1134 op
->ival1
= msg_head
->ival1
;
1135 op
->ival2
= msg_head
->ival2
;
1136 op
->kt_ival1
= timeval_to_ktime(msg_head
->ival1
);
1137 op
->kt_ival2
= timeval_to_ktime(msg_head
->ival2
);
1139 /* disable an active timer due to zero value? */
1140 if (!op
->kt_ival1
.tv64
)
1141 hrtimer_cancel(&op
->timer
);
1144 * In any case cancel the throttle timer, flush
1145 * potentially blocked msgs and reset throttle handling
1147 op
->kt_lastmsg
= ktime_set(0, 0);
1148 hrtimer_cancel(&op
->thrtimer
);
1149 bcm_rx_thr_flush(op
, 1);
1152 if ((op
->flags
& STARTTIMER
) && op
->kt_ival1
.tv64
)
1153 hrtimer_start(&op
->timer
, op
->kt_ival1
,
1157 /* now we can register for can_ids, if we added a new bcm_op */
1158 if (do_rx_register
) {
1160 struct net_device
*dev
;
1162 dev
= dev_get_by_index(&init_net
, ifindex
);
1164 err
= can_rx_register(dev
, op
->can_id
,
1165 REGMASK(op
->can_id
),
1169 op
->rx_reg_dev
= dev
;
1174 err
= can_rx_register(NULL
, op
->can_id
,
1175 REGMASK(op
->can_id
),
1176 bcm_rx_handler
, op
, "bcm");
1178 /* this bcm rx op is broken -> remove it */
1179 list_del(&op
->list
);
1185 return msg_head
->nframes
* CFSIZ
+ MHSIZ
;
1189 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg)
1191 static int bcm_tx_send(struct msghdr
*msg
, int ifindex
, struct sock
*sk
)
1193 struct sk_buff
*skb
;
1194 struct net_device
*dev
;
1197 /* we need a real device to send frames */
1201 skb
= alloc_skb(CFSIZ
+ sizeof(struct can_skb_priv
), GFP_KERNEL
);
1205 can_skb_reserve(skb
);
1207 err
= memcpy_from_msg(skb_put(skb
, CFSIZ
), msg
, CFSIZ
);
1213 dev
= dev_get_by_index(&init_net
, ifindex
);
1219 can_skb_prv(skb
)->ifindex
= dev
->ifindex
;
1221 can_skb_set_owner(skb
, sk
);
1222 err
= can_send(skb
, 1); /* send with loopback */
1228 return CFSIZ
+ MHSIZ
;
1232 * bcm_sendmsg - process BCM commands (opcodes) from the userspace
1234 static int bcm_sendmsg(struct kiocb
*iocb
, struct socket
*sock
,
1235 struct msghdr
*msg
, size_t size
)
1237 struct sock
*sk
= sock
->sk
;
1238 struct bcm_sock
*bo
= bcm_sk(sk
);
1239 int ifindex
= bo
->ifindex
; /* default ifindex for this bcm_op */
1240 struct bcm_msg_head msg_head
;
1241 int ret
; /* read bytes or error codes as return value */
1246 /* check for valid message length from userspace */
1247 if (size
< MHSIZ
|| (size
- MHSIZ
) % CFSIZ
)
1250 /* check for alternative ifindex for this bcm_op */
1252 if (!ifindex
&& msg
->msg_name
) {
1253 /* no bound device as default => check msg_name */
1254 DECLARE_SOCKADDR(struct sockaddr_can
*, addr
, msg
->msg_name
);
1256 if (msg
->msg_namelen
< sizeof(*addr
))
1259 if (addr
->can_family
!= AF_CAN
)
1262 /* ifindex from sendto() */
1263 ifindex
= addr
->can_ifindex
;
1266 struct net_device
*dev
;
1268 dev
= dev_get_by_index(&init_net
, ifindex
);
1272 if (dev
->type
!= ARPHRD_CAN
) {
1281 /* read message head information */
1283 ret
= memcpy_from_msg((u8
*)&msg_head
, msg
, MHSIZ
);
1289 switch (msg_head
.opcode
) {
1292 ret
= bcm_tx_setup(&msg_head
, msg
, ifindex
, sk
);
1296 ret
= bcm_rx_setup(&msg_head
, msg
, ifindex
, sk
);
1300 if (bcm_delete_tx_op(&bo
->tx_ops
, msg_head
.can_id
, ifindex
))
1307 if (bcm_delete_rx_op(&bo
->rx_ops
, msg_head
.can_id
, ifindex
))
1314 /* reuse msg_head for the reply to TX_READ */
1315 msg_head
.opcode
= TX_STATUS
;
1316 ret
= bcm_read_op(&bo
->tx_ops
, &msg_head
, ifindex
);
1320 /* reuse msg_head for the reply to RX_READ */
1321 msg_head
.opcode
= RX_STATUS
;
1322 ret
= bcm_read_op(&bo
->rx_ops
, &msg_head
, ifindex
);
1326 /* we need exactly one can_frame behind the msg head */
1327 if ((msg_head
.nframes
!= 1) || (size
!= CFSIZ
+ MHSIZ
))
1330 ret
= bcm_tx_send(msg
, ifindex
, sk
);
1344 * notification handler for netdevice status changes
1346 static int bcm_notifier(struct notifier_block
*nb
, unsigned long msg
,
1349 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
1350 struct bcm_sock
*bo
= container_of(nb
, struct bcm_sock
, notifier
);
1351 struct sock
*sk
= &bo
->sk
;
1353 int notify_enodev
= 0;
1355 if (!net_eq(dev_net(dev
), &init_net
))
1358 if (dev
->type
!= ARPHRD_CAN
)
1363 case NETDEV_UNREGISTER
:
1366 /* remove device specific receive entries */
1367 list_for_each_entry(op
, &bo
->rx_ops
, list
)
1368 if (op
->rx_reg_dev
== dev
)
1369 bcm_rx_unreg(dev
, op
);
1371 /* remove device reference, if this is our bound device */
1372 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1380 if (notify_enodev
) {
1381 sk
->sk_err
= ENODEV
;
1382 if (!sock_flag(sk
, SOCK_DEAD
))
1383 sk
->sk_error_report(sk
);
1388 if (bo
->bound
&& bo
->ifindex
== dev
->ifindex
) {
1389 sk
->sk_err
= ENETDOWN
;
1390 if (!sock_flag(sk
, SOCK_DEAD
))
1391 sk
->sk_error_report(sk
);
1399 * initial settings for all BCM sockets to be set at socket creation time
1401 static int bcm_init(struct sock
*sk
)
1403 struct bcm_sock
*bo
= bcm_sk(sk
);
1407 bo
->dropped_usr_msgs
= 0;
1408 bo
->bcm_proc_read
= NULL
;
1410 INIT_LIST_HEAD(&bo
->tx_ops
);
1411 INIT_LIST_HEAD(&bo
->rx_ops
);
1414 bo
->notifier
.notifier_call
= bcm_notifier
;
1416 register_netdevice_notifier(&bo
->notifier
);
1422 * standard socket functions
1424 static int bcm_release(struct socket
*sock
)
1426 struct sock
*sk
= sock
->sk
;
1427 struct bcm_sock
*bo
;
1428 struct bcm_op
*op
, *next
;
1435 /* remove bcm_ops, timer, rx_unregister(), etc. */
1437 unregister_netdevice_notifier(&bo
->notifier
);
1441 list_for_each_entry_safe(op
, next
, &bo
->tx_ops
, list
)
1444 list_for_each_entry_safe(op
, next
, &bo
->rx_ops
, list
) {
1446 * Don't care if we're bound or not (due to netdev problems)
1447 * can_rx_unregister() is always a save thing to do here.
1451 * Only remove subscriptions that had not
1452 * been removed due to NETDEV_UNREGISTER
1455 if (op
->rx_reg_dev
) {
1456 struct net_device
*dev
;
1458 dev
= dev_get_by_index(&init_net
, op
->ifindex
);
1460 bcm_rx_unreg(dev
, op
);
1465 can_rx_unregister(NULL
, op
->can_id
,
1466 REGMASK(op
->can_id
),
1467 bcm_rx_handler
, op
);
1472 /* remove procfs entry */
1473 if (proc_dir
&& bo
->bcm_proc_read
)
1474 remove_proc_entry(bo
->procname
, proc_dir
);
1476 /* remove device reference */
1491 static int bcm_connect(struct socket
*sock
, struct sockaddr
*uaddr
, int len
,
1494 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
1495 struct sock
*sk
= sock
->sk
;
1496 struct bcm_sock
*bo
= bcm_sk(sk
);
1498 if (len
< sizeof(*addr
))
1504 /* bind a device to this socket */
1505 if (addr
->can_ifindex
) {
1506 struct net_device
*dev
;
1508 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
1512 if (dev
->type
!= ARPHRD_CAN
) {
1517 bo
->ifindex
= dev
->ifindex
;
1521 /* no interface reference for ifindex = 0 ('any' CAN device) */
1528 /* unique socket address as filename */
1529 sprintf(bo
->procname
, "%lu", sock_i_ino(sk
));
1530 bo
->bcm_proc_read
= proc_create_data(bo
->procname
, 0644,
1532 &bcm_proc_fops
, sk
);
1538 static int bcm_recvmsg(struct kiocb
*iocb
, struct socket
*sock
,
1539 struct msghdr
*msg
, size_t size
, int flags
)
1541 struct sock
*sk
= sock
->sk
;
1542 struct sk_buff
*skb
;
1547 noblock
= flags
& MSG_DONTWAIT
;
1548 flags
&= ~MSG_DONTWAIT
;
1549 skb
= skb_recv_datagram(sk
, flags
, noblock
, &error
);
1553 if (skb
->len
< size
)
1556 err
= memcpy_to_msg(msg
, skb
->data
, size
);
1558 skb_free_datagram(sk
, skb
);
1562 sock_recv_ts_and_drops(msg
, sk
, skb
);
1564 if (msg
->msg_name
) {
1565 __sockaddr_check_size(sizeof(struct sockaddr_can
));
1566 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
1567 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
1570 skb_free_datagram(sk
, skb
);
1575 static const struct proto_ops bcm_ops
= {
1577 .release
= bcm_release
,
1578 .bind
= sock_no_bind
,
1579 .connect
= bcm_connect
,
1580 .socketpair
= sock_no_socketpair
,
1581 .accept
= sock_no_accept
,
1582 .getname
= sock_no_getname
,
1583 .poll
= datagram_poll
,
1584 .ioctl
= can_ioctl
, /* use can_ioctl() from af_can.c */
1585 .listen
= sock_no_listen
,
1586 .shutdown
= sock_no_shutdown
,
1587 .setsockopt
= sock_no_setsockopt
,
1588 .getsockopt
= sock_no_getsockopt
,
1589 .sendmsg
= bcm_sendmsg
,
1590 .recvmsg
= bcm_recvmsg
,
1591 .mmap
= sock_no_mmap
,
1592 .sendpage
= sock_no_sendpage
,
1595 static struct proto bcm_proto __read_mostly
= {
1597 .owner
= THIS_MODULE
,
1598 .obj_size
= sizeof(struct bcm_sock
),
1602 static const struct can_proto bcm_can_proto
= {
1604 .protocol
= CAN_BCM
,
1609 static int __init
bcm_module_init(void)
1613 pr_info("can: broadcast manager protocol (rev " CAN_BCM_VERSION
" t)\n");
1615 err
= can_proto_register(&bcm_can_proto
);
1617 printk(KERN_ERR
"can: registration of bcm protocol failed\n");
1621 /* create /proc/net/can-bcm directory */
1622 proc_dir
= proc_mkdir("can-bcm", init_net
.proc_net
);
1626 static void __exit
bcm_module_exit(void)
1628 can_proto_unregister(&bcm_can_proto
);
1631 remove_proc_entry("can-bcm", init_net
.proc_net
);
1634 module_init(bcm_module_init
);
1635 module_exit(bcm_module_exit
);