2 * af_can.c - Protocol family CAN core module
3 * (used by different CAN protocol modules)
5 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of Volkswagen nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * Alternatively, provided that this notice is retained in full, this
21 * software may be distributed under the terms of the GNU General
22 * Public License ("GPL") version 2, in which case the provisions of the
23 * GPL apply INSTEAD OF those given above.
25 * The provided data structures and external interfaces from this code
26 * are not restricted to be used by modules with a GPL compatible license.
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
43 #include <linux/module.h>
44 #include <linux/stddef.h>
45 #include <linux/init.h>
46 #include <linux/kmod.h>
47 #include <linux/slab.h>
48 #include <linux/list.h>
49 #include <linux/spinlock.h>
50 #include <linux/rcupdate.h>
51 #include <linux/uaccess.h>
52 #include <linux/net.h>
53 #include <linux/netdevice.h>
54 #include <linux/socket.h>
55 #include <linux/if_ether.h>
56 #include <linux/if_arp.h>
57 #include <linux/skbuff.h>
58 #include <linux/can.h>
59 #include <linux/can/core.h>
60 #include <linux/can/skb.h>
61 #include <linux/ratelimit.h>
62 #include <net/net_namespace.h>
67 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
68 MODULE_LICENSE("Dual BSD/GPL");
69 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
70 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
72 MODULE_ALIAS_NETPROTO(PF_CAN
);
74 static int stats_timer __read_mostly
= 1;
75 module_param(stats_timer
, int, S_IRUGO
);
76 MODULE_PARM_DESC(stats_timer
, "enable timer for statistics (default:on)");
78 /* receive filters subscribed for 'all' CAN devices */
79 struct dev_rcv_lists can_rx_alldev_list
;
80 static DEFINE_SPINLOCK(can_rcvlists_lock
);
82 static struct kmem_cache
*rcv_cache __read_mostly
;
84 /* table of registered CAN protocols */
85 static const struct can_proto
*proto_tab
[CAN_NPROTO
] __read_mostly
;
86 static DEFINE_MUTEX(proto_tab_lock
);
88 struct timer_list can_stattimer
; /* timer for statistics update */
89 struct s_stats can_stats
; /* packet statistics */
90 struct s_pstats can_pstats
; /* receive list statistics */
93 * af_can socket functions
96 int can_ioctl(struct socket
*sock
, unsigned int cmd
, unsigned long arg
)
98 struct sock
*sk
= sock
->sk
;
103 return sock_get_timestamp(sk
, (struct timeval __user
*)arg
);
109 EXPORT_SYMBOL(can_ioctl
);
111 static void can_sock_destruct(struct sock
*sk
)
113 skb_queue_purge(&sk
->sk_receive_queue
);
116 static const struct can_proto
*can_get_proto(int protocol
)
118 const struct can_proto
*cp
;
121 cp
= rcu_dereference(proto_tab
[protocol
]);
122 if (cp
&& !try_module_get(cp
->prot
->owner
))
129 static inline void can_put_proto(const struct can_proto
*cp
)
131 module_put(cp
->prot
->owner
);
134 static int can_create(struct net
*net
, struct socket
*sock
, int protocol
,
138 const struct can_proto
*cp
;
141 sock
->state
= SS_UNCONNECTED
;
143 if (protocol
< 0 || protocol
>= CAN_NPROTO
)
146 if (!net_eq(net
, &init_net
))
147 return -EAFNOSUPPORT
;
149 cp
= can_get_proto(protocol
);
151 #ifdef CONFIG_MODULES
153 /* try to load protocol module if kernel is modular */
155 err
= request_module("can-proto-%d", protocol
);
158 * In case of error we only print a message but don't
159 * return the error code immediately. Below we will
160 * return -EPROTONOSUPPORT
163 printk_ratelimited(KERN_ERR
"can: request_module "
164 "(can-proto-%d) failed.\n", protocol
);
166 cp
= can_get_proto(protocol
);
170 /* check for available protocol and correct usage */
173 return -EPROTONOSUPPORT
;
175 if (cp
->type
!= sock
->type
) {
182 sk
= sk_alloc(net
, PF_CAN
, GFP_KERNEL
, cp
->prot
, kern
);
188 sock_init_data(sock
, sk
);
189 sk
->sk_destruct
= can_sock_destruct
;
191 if (sk
->sk_prot
->init
)
192 err
= sk
->sk_prot
->init(sk
);
195 /* release sk on errors */
210 * can_send - transmit a CAN frame (optional with local loopback)
211 * @skb: pointer to socket buffer with CAN frame in data section
212 * @loop: loopback for listeners on local CAN sockets (recommended default!)
214 * Due to the loopback this routine must not be called from hardirq context.
218 * -ENETDOWN when the selected interface is down
219 * -ENOBUFS on full driver queue (see net_xmit_errno())
220 * -ENOMEM when local loopback failed at calling skb_clone()
221 * -EPERM when trying to send on a non-CAN interface
222 * -EMSGSIZE CAN frame size is bigger than CAN interface MTU
223 * -EINVAL when the skb->data does not contain a valid CAN frame
225 int can_send(struct sk_buff
*skb
, int loop
)
227 struct sk_buff
*newskb
= NULL
;
228 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
231 if (skb
->len
== CAN_MTU
) {
232 skb
->protocol
= htons(ETH_P_CAN
);
233 if (unlikely(cfd
->len
> CAN_MAX_DLEN
))
235 } else if (skb
->len
== CANFD_MTU
) {
236 skb
->protocol
= htons(ETH_P_CANFD
);
237 if (unlikely(cfd
->len
> CANFD_MAX_DLEN
))
243 * Make sure the CAN frame can pass the selected CAN netdevice.
244 * As structs can_frame and canfd_frame are similar, we can provide
245 * CAN FD frames to legacy CAN drivers as long as the length is <= 8
247 if (unlikely(skb
->len
> skb
->dev
->mtu
&& cfd
->len
> CAN_MAX_DLEN
)) {
252 if (unlikely(skb
->dev
->type
!= ARPHRD_CAN
)) {
257 if (unlikely(!(skb
->dev
->flags
& IFF_UP
))) {
262 skb
->ip_summed
= CHECKSUM_UNNECESSARY
;
264 skb_reset_mac_header(skb
);
265 skb_reset_network_header(skb
);
266 skb_reset_transport_header(skb
);
269 /* local loopback of sent CAN frames */
271 /* indication for the CAN driver: do loopback */
272 skb
->pkt_type
= PACKET_LOOPBACK
;
275 * The reference to the originating sock may be required
276 * by the receiving socket to check whether the frame is
277 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
278 * Therefore we have to ensure that skb->sk remains the
279 * reference to the originating sock by restoring skb->sk
280 * after each skb_clone() or skb_orphan() usage.
283 if (!(skb
->dev
->flags
& IFF_ECHO
)) {
285 * If the interface is not capable to do loopback
286 * itself, we do it here.
288 newskb
= skb_clone(skb
, GFP_ATOMIC
);
294 can_skb_set_owner(newskb
, skb
->sk
);
295 newskb
->ip_summed
= CHECKSUM_UNNECESSARY
;
296 newskb
->pkt_type
= PACKET_BROADCAST
;
299 /* indication for the CAN driver: no loopback required */
300 skb
->pkt_type
= PACKET_HOST
;
303 /* send to netdevice */
304 err
= dev_queue_xmit(skb
);
306 err
= net_xmit_errno(err
);
314 if (!(newskb
->tstamp
.tv64
))
315 __net_timestamp(newskb
);
320 /* update statistics */
321 can_stats
.tx_frames
++;
322 can_stats
.tx_frames_delta
++;
330 EXPORT_SYMBOL(can_send
);
336 static struct dev_rcv_lists
*find_dev_rcv_lists(struct net_device
*dev
)
339 return &can_rx_alldev_list
;
341 return (struct dev_rcv_lists
*)dev
->ml_priv
;
345 * effhash - hash function for 29 bit CAN identifier reduction
346 * @can_id: 29 bit CAN identifier
349 * To reduce the linear traversal in one linked list of _single_ EFF CAN
350 * frame subscriptions the 29 bit identifier is mapped to 10 bits.
351 * (see CAN_EFF_RCV_HASH_BITS definition)
354 * Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask )
356 static unsigned int effhash(canid_t can_id
)
361 hash
^= can_id
>> CAN_EFF_RCV_HASH_BITS
;
362 hash
^= can_id
>> (2 * CAN_EFF_RCV_HASH_BITS
);
364 return hash
& ((1 << CAN_EFF_RCV_HASH_BITS
) - 1);
368 * find_rcv_list - determine optimal filterlist inside device filter struct
369 * @can_id: pointer to CAN identifier of a given can_filter
370 * @mask: pointer to CAN mask of a given can_filter
371 * @d: pointer to the device filter struct
374 * Returns the optimal filterlist to reduce the filter handling in the
375 * receive path. This function is called by service functions that need
376 * to register or unregister a can_filter in the filter lists.
378 * A filter matches in general, when
380 * <received_can_id> & mask == can_id & mask
382 * so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe
383 * relevant bits for the filter.
385 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
386 * filter for error messages (CAN_ERR_FLAG bit set in mask). For error msg
387 * frames there is a special filterlist and a special rx path filter handling.
390 * Pointer to optimal filterlist for the given can_id/mask pair.
391 * Constistency checked mask.
392 * Reduced can_id to have a preprocessed filter compare value.
394 static struct hlist_head
*find_rcv_list(canid_t
*can_id
, canid_t
*mask
,
395 struct dev_rcv_lists
*d
)
397 canid_t inv
= *can_id
& CAN_INV_FILTER
; /* save flag before masking */
399 /* filter for error message frames in extra filterlist */
400 if (*mask
& CAN_ERR_FLAG
) {
401 /* clear CAN_ERR_FLAG in filter entry */
402 *mask
&= CAN_ERR_MASK
;
403 return &d
->rx
[RX_ERR
];
406 /* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */
408 #define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG)
410 /* ensure valid values in can_mask for 'SFF only' frame filtering */
411 if ((*mask
& CAN_EFF_FLAG
) && !(*can_id
& CAN_EFF_FLAG
))
412 *mask
&= (CAN_SFF_MASK
| CAN_EFF_RTR_FLAGS
);
414 /* reduce condition testing at receive time */
417 /* inverse can_id/can_mask filter */
419 return &d
->rx
[RX_INV
];
421 /* mask == 0 => no condition testing at receive time */
423 return &d
->rx
[RX_ALL
];
425 /* extra filterlists for the subscription of a single non-RTR can_id */
426 if (((*mask
& CAN_EFF_RTR_FLAGS
) == CAN_EFF_RTR_FLAGS
) &&
427 !(*can_id
& CAN_RTR_FLAG
)) {
429 if (*can_id
& CAN_EFF_FLAG
) {
430 if (*mask
== (CAN_EFF_MASK
| CAN_EFF_RTR_FLAGS
))
431 return &d
->rx_eff
[effhash(*can_id
)];
433 if (*mask
== (CAN_SFF_MASK
| CAN_EFF_RTR_FLAGS
))
434 return &d
->rx_sff
[*can_id
];
438 /* default: filter via can_id/can_mask */
439 return &d
->rx
[RX_FIL
];
443 * can_rx_register - subscribe CAN frames from a specific interface
444 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
445 * @can_id: CAN identifier (see description)
446 * @mask: CAN mask (see description)
447 * @func: callback function on filter match
448 * @data: returned parameter for callback function
449 * @ident: string for calling module identification
452 * Invokes the callback function with the received sk_buff and the given
453 * parameter 'data' on a matching receive filter. A filter matches, when
455 * <received_can_id> & mask == can_id & mask
457 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
458 * filter for error message frames (CAN_ERR_FLAG bit set in mask).
460 * The provided pointer to the sk_buff is guaranteed to be valid as long as
461 * the callback function is running. The callback function must *not* free
462 * the given sk_buff while processing it's task. When the given sk_buff is
463 * needed after the end of the callback function it must be cloned inside
464 * the callback function with skb_clone().
468 * -ENOMEM on missing cache mem to create subscription entry
469 * -ENODEV unknown device
471 int can_rx_register(struct net_device
*dev
, canid_t can_id
, canid_t mask
,
472 void (*func
)(struct sk_buff
*, void *), void *data
,
476 struct hlist_head
*rl
;
477 struct dev_rcv_lists
*d
;
480 /* insert new receiver (dev,canid,mask) -> (func,data) */
482 if (dev
&& dev
->type
!= ARPHRD_CAN
)
485 r
= kmem_cache_alloc(rcv_cache
, GFP_KERNEL
);
489 spin_lock(&can_rcvlists_lock
);
491 d
= find_dev_rcv_lists(dev
);
493 rl
= find_rcv_list(&can_id
, &mask
, d
);
502 hlist_add_head_rcu(&r
->list
, rl
);
505 can_pstats
.rcv_entries
++;
506 if (can_pstats
.rcv_entries_max
< can_pstats
.rcv_entries
)
507 can_pstats
.rcv_entries_max
= can_pstats
.rcv_entries
;
509 kmem_cache_free(rcv_cache
, r
);
513 spin_unlock(&can_rcvlists_lock
);
517 EXPORT_SYMBOL(can_rx_register
);
520 * can_rx_delete_receiver - rcu callback for single receiver entry removal
522 static void can_rx_delete_receiver(struct rcu_head
*rp
)
524 struct receiver
*r
= container_of(rp
, struct receiver
, rcu
);
526 kmem_cache_free(rcv_cache
, r
);
530 * can_rx_unregister - unsubscribe CAN frames from a specific interface
531 * @dev: pointer to netdevice (NULL => unsubscribe from 'all' CAN devices list)
532 * @can_id: CAN identifier
534 * @func: callback function on filter match
535 * @data: returned parameter for callback function
538 * Removes subscription entry depending on given (subscription) values.
540 void can_rx_unregister(struct net_device
*dev
, canid_t can_id
, canid_t mask
,
541 void (*func
)(struct sk_buff
*, void *), void *data
)
543 struct receiver
*r
= NULL
;
544 struct hlist_head
*rl
;
545 struct dev_rcv_lists
*d
;
547 if (dev
&& dev
->type
!= ARPHRD_CAN
)
550 spin_lock(&can_rcvlists_lock
);
552 d
= find_dev_rcv_lists(dev
);
554 pr_err("BUG: receive list not found for "
555 "dev %s, id %03X, mask %03X\n",
556 DNAME(dev
), can_id
, mask
);
560 rl
= find_rcv_list(&can_id
, &mask
, d
);
563 * Search the receiver list for the item to delete. This should
564 * exist, since no receiver may be unregistered that hasn't
565 * been registered before.
568 hlist_for_each_entry_rcu(r
, rl
, list
) {
569 if (r
->can_id
== can_id
&& r
->mask
== mask
&&
570 r
->func
== func
&& r
->data
== data
)
575 * Check for bugs in CAN protocol implementations using af_can.c:
576 * 'r' will be NULL if no matching list item was found for removal.
580 WARN(1, "BUG: receive list entry not found for dev %s, "
581 "id %03X, mask %03X\n", DNAME(dev
), can_id
, mask
);
585 hlist_del_rcu(&r
->list
);
588 if (can_pstats
.rcv_entries
> 0)
589 can_pstats
.rcv_entries
--;
591 /* remove device structure requested by NETDEV_UNREGISTER */
592 if (d
->remove_on_zero_entries
&& !d
->entries
) {
598 spin_unlock(&can_rcvlists_lock
);
600 /* schedule the receiver item for deletion */
602 call_rcu(&r
->rcu
, can_rx_delete_receiver
);
604 EXPORT_SYMBOL(can_rx_unregister
);
606 static inline void deliver(struct sk_buff
*skb
, struct receiver
*r
)
608 r
->func(skb
, r
->data
);
612 static int can_rcv_filter(struct dev_rcv_lists
*d
, struct sk_buff
*skb
)
616 struct can_frame
*cf
= (struct can_frame
*)skb
->data
;
617 canid_t can_id
= cf
->can_id
;
622 if (can_id
& CAN_ERR_FLAG
) {
623 /* check for error message frame entries only */
624 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_ERR
], list
) {
625 if (can_id
& r
->mask
) {
633 /* check for unfiltered entries */
634 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_ALL
], list
) {
639 /* check for can_id/mask entries */
640 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_FIL
], list
) {
641 if ((can_id
& r
->mask
) == r
->can_id
) {
647 /* check for inverted can_id/mask entries */
648 hlist_for_each_entry_rcu(r
, &d
->rx
[RX_INV
], list
) {
649 if ((can_id
& r
->mask
) != r
->can_id
) {
655 /* check filterlists for single non-RTR can_ids */
656 if (can_id
& CAN_RTR_FLAG
)
659 if (can_id
& CAN_EFF_FLAG
) {
660 hlist_for_each_entry_rcu(r
, &d
->rx_eff
[effhash(can_id
)], list
) {
661 if (r
->can_id
== can_id
) {
667 can_id
&= CAN_SFF_MASK
;
668 hlist_for_each_entry_rcu(r
, &d
->rx_sff
[can_id
], list
) {
677 static void can_receive(struct sk_buff
*skb
, struct net_device
*dev
)
679 struct dev_rcv_lists
*d
;
682 /* update statistics */
683 can_stats
.rx_frames
++;
684 can_stats
.rx_frames_delta
++;
688 /* deliver the packet to sockets listening on all devices */
689 matches
= can_rcv_filter(&can_rx_alldev_list
, skb
);
691 /* find receive list for this device */
692 d
= find_dev_rcv_lists(dev
);
694 matches
+= can_rcv_filter(d
, skb
);
698 /* consume the skbuff allocated by the netdevice driver */
703 can_stats
.matches_delta
++;
707 static int can_rcv(struct sk_buff
*skb
, struct net_device
*dev
,
708 struct packet_type
*pt
, struct net_device
*orig_dev
)
710 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
712 if (unlikely(!net_eq(dev_net(dev
), &init_net
)))
715 if (WARN_ONCE(dev
->type
!= ARPHRD_CAN
||
716 skb
->len
!= CAN_MTU
||
717 cfd
->len
> CAN_MAX_DLEN
,
718 "PF_CAN: dropped non conform CAN skbuf: "
719 "dev type %d, len %d, datalen %d\n",
720 dev
->type
, skb
->len
, cfd
->len
))
723 can_receive(skb
, dev
);
724 return NET_RX_SUCCESS
;
731 static int canfd_rcv(struct sk_buff
*skb
, struct net_device
*dev
,
732 struct packet_type
*pt
, struct net_device
*orig_dev
)
734 struct canfd_frame
*cfd
= (struct canfd_frame
*)skb
->data
;
736 if (unlikely(!net_eq(dev_net(dev
), &init_net
)))
739 if (WARN_ONCE(dev
->type
!= ARPHRD_CAN
||
740 skb
->len
!= CANFD_MTU
||
741 cfd
->len
> CANFD_MAX_DLEN
,
742 "PF_CAN: dropped non conform CAN FD skbuf: "
743 "dev type %d, len %d, datalen %d\n",
744 dev
->type
, skb
->len
, cfd
->len
))
747 can_receive(skb
, dev
);
748 return NET_RX_SUCCESS
;
756 * af_can protocol functions
760 * can_proto_register - register CAN transport protocol
761 * @cp: pointer to CAN protocol structure
765 * -EINVAL invalid (out of range) protocol number
766 * -EBUSY protocol already in use
767 * -ENOBUF if proto_register() fails
769 int can_proto_register(const struct can_proto
*cp
)
771 int proto
= cp
->protocol
;
774 if (proto
< 0 || proto
>= CAN_NPROTO
) {
775 pr_err("can: protocol number %d out of range\n", proto
);
779 err
= proto_register(cp
->prot
, 0);
783 mutex_lock(&proto_tab_lock
);
785 if (proto_tab
[proto
]) {
786 pr_err("can: protocol %d already registered\n", proto
);
789 RCU_INIT_POINTER(proto_tab
[proto
], cp
);
791 mutex_unlock(&proto_tab_lock
);
794 proto_unregister(cp
->prot
);
798 EXPORT_SYMBOL(can_proto_register
);
801 * can_proto_unregister - unregister CAN transport protocol
802 * @cp: pointer to CAN protocol structure
804 void can_proto_unregister(const struct can_proto
*cp
)
806 int proto
= cp
->protocol
;
808 mutex_lock(&proto_tab_lock
);
809 BUG_ON(proto_tab
[proto
] != cp
);
810 RCU_INIT_POINTER(proto_tab
[proto
], NULL
);
811 mutex_unlock(&proto_tab_lock
);
815 proto_unregister(cp
->prot
);
817 EXPORT_SYMBOL(can_proto_unregister
);
820 * af_can notifier to create/remove CAN netdevice specific structs
822 static int can_notifier(struct notifier_block
*nb
, unsigned long msg
,
825 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
826 struct dev_rcv_lists
*d
;
828 if (!net_eq(dev_net(dev
), &init_net
))
831 if (dev
->type
!= ARPHRD_CAN
)
836 case NETDEV_REGISTER
:
838 /* create new dev_rcv_lists for this device */
839 d
= kzalloc(sizeof(*d
), GFP_KERNEL
);
842 BUG_ON(dev
->ml_priv
);
847 case NETDEV_UNREGISTER
:
848 spin_lock(&can_rcvlists_lock
);
853 d
->remove_on_zero_entries
= 1;
859 pr_err("can: notifier: receive list not found for dev "
862 spin_unlock(&can_rcvlists_lock
);
871 * af_can module init/exit functions
874 static struct packet_type can_packet __read_mostly
= {
875 .type
= cpu_to_be16(ETH_P_CAN
),
879 static struct packet_type canfd_packet __read_mostly
= {
880 .type
= cpu_to_be16(ETH_P_CANFD
),
884 static const struct net_proto_family can_family_ops
= {
886 .create
= can_create
,
887 .owner
= THIS_MODULE
,
890 /* notifier block for netdevice event */
891 static struct notifier_block can_netdev_notifier __read_mostly
= {
892 .notifier_call
= can_notifier
,
895 static __init
int can_init(void)
897 /* check for correct padding to be able to use the structs similarly */
898 BUILD_BUG_ON(offsetof(struct can_frame
, can_dlc
) !=
899 offsetof(struct canfd_frame
, len
) ||
900 offsetof(struct can_frame
, data
) !=
901 offsetof(struct canfd_frame
, data
));
903 pr_info("can: controller area network core (" CAN_VERSION_STRING
")\n");
905 memset(&can_rx_alldev_list
, 0, sizeof(can_rx_alldev_list
));
907 rcv_cache
= kmem_cache_create("can_receiver", sizeof(struct receiver
),
913 /* the statistics are updated every second (timer triggered) */
914 setup_timer(&can_stattimer
, can_stat_update
, 0);
915 mod_timer(&can_stattimer
, round_jiffies(jiffies
+ HZ
));
917 can_stattimer
.function
= NULL
;
921 /* protocol register */
922 sock_register(&can_family_ops
);
923 register_netdevice_notifier(&can_netdev_notifier
);
924 dev_add_pack(&can_packet
);
925 dev_add_pack(&canfd_packet
);
930 static __exit
void can_exit(void)
932 struct net_device
*dev
;
935 del_timer_sync(&can_stattimer
);
939 /* protocol unregister */
940 dev_remove_pack(&canfd_packet
);
941 dev_remove_pack(&can_packet
);
942 unregister_netdevice_notifier(&can_netdev_notifier
);
943 sock_unregister(PF_CAN
);
945 /* remove created dev_rcv_lists from still registered CAN devices */
947 for_each_netdev_rcu(&init_net
, dev
) {
948 if (dev
->type
== ARPHRD_CAN
&& dev
->ml_priv
) {
950 struct dev_rcv_lists
*d
= dev
->ml_priv
;
959 rcu_barrier(); /* Wait for completion of call_rcu()'s */
961 kmem_cache_destroy(rcv_cache
);
964 module_init(can_init
);
965 module_exit(can_exit
);