1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /* af_can.c - Protocol family CAN core module
3 * (used by different CAN protocol modules)
5 * Copyright (c) 2002-2017 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, 0444);
76 MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
78 static struct kmem_cache *rcv_cache __read_mostly;
80 /* table of registered CAN protocols */
81 static const struct can_proto __rcu *proto_tab[CAN_NPROTO] __read_mostly;
82 static DEFINE_MUTEX(proto_tab_lock);
84 static atomic_t skbcounter = ATOMIC_INIT(0);
86 /* af_can socket functions */
88 static void can_sock_destruct(struct sock *sk)
90 skb_queue_purge(&sk->sk_receive_queue);
91 skb_queue_purge(&sk->sk_error_queue);
94 static const struct can_proto *can_get_proto(int protocol)
96 const struct can_proto *cp;
99 cp = rcu_dereference(proto_tab[protocol]);
100 if (cp && !try_module_get(cp->prot->owner))
107 static inline void can_put_proto(const struct can_proto *cp)
109 module_put(cp->prot->owner);
112 static int can_create(struct net *net, struct socket *sock, int protocol,
116 const struct can_proto *cp;
119 sock->state = SS_UNCONNECTED;
121 if (protocol < 0 || protocol >= CAN_NPROTO)
124 cp = can_get_proto(protocol);
126 #ifdef CONFIG_MODULES
128 /* try to load protocol module if kernel is modular */
130 err = request_module("can-proto-%d", protocol);
132 /* In case of error we only print a message but don't
133 * return the error code immediately. Below we will
134 * return -EPROTONOSUPPORT
137 pr_err_ratelimited("can: request_module (can-proto-%d) failed.\n",
140 cp = can_get_proto(protocol);
144 /* check for available protocol and correct usage */
147 return -EPROTONOSUPPORT;
149 if (cp->type != sock->type) {
156 sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot, kern);
162 sock_init_data(sock, sk);
163 sk->sk_destruct = can_sock_destruct;
165 if (sk->sk_prot->init)
166 err = sk->sk_prot->init(sk);
169 /* release sk on errors */
182 * can_send - transmit a CAN frame (optional with local loopback)
183 * @skb: pointer to socket buffer with CAN frame in data section
184 * @loop: loopback for listeners on local CAN sockets (recommended default!)
186 * Due to the loopback this routine must not be called from hardirq context.
190 * -ENETDOWN when the selected interface is down
191 * -ENOBUFS on full driver queue (see net_xmit_errno())
192 * -ENOMEM when local loopback failed at calling skb_clone()
193 * -EPERM when trying to send on a non-CAN interface
194 * -EMSGSIZE CAN frame size is bigger than CAN interface MTU
195 * -EINVAL when the skb->data does not contain a valid CAN frame
197 int can_send(struct sk_buff *skb, int loop)
199 struct sk_buff *newskb = NULL;
200 struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
201 struct s_stats *can_stats = dev_net(skb->dev)->can.can_stats;
204 if (skb->len == CAN_MTU) {
205 skb->protocol = htons(ETH_P_CAN);
206 if (unlikely(cfd->len > CAN_MAX_DLEN))
208 } else if (skb->len == CANFD_MTU) {
209 skb->protocol = htons(ETH_P_CANFD);
210 if (unlikely(cfd->len > CANFD_MAX_DLEN))
216 /* Make sure the CAN frame can pass the selected CAN netdevice.
217 * As structs can_frame and canfd_frame are similar, we can provide
218 * CAN FD frames to legacy CAN drivers as long as the length is <= 8
220 if (unlikely(skb->len > skb->dev->mtu && cfd->len > CAN_MAX_DLEN)) {
225 if (unlikely(skb->dev->type != ARPHRD_CAN)) {
230 if (unlikely(!(skb->dev->flags & IFF_UP))) {
235 skb->ip_summed = CHECKSUM_UNNECESSARY;
237 skb_reset_mac_header(skb);
238 skb_reset_network_header(skb);
239 skb_reset_transport_header(skb);
242 /* local loopback of sent CAN frames */
244 /* indication for the CAN driver: do loopback */
245 skb->pkt_type = PACKET_LOOPBACK;
247 /* The reference to the originating sock may be required
248 * by the receiving socket to check whether the frame is
249 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
250 * Therefore we have to ensure that skb->sk remains the
251 * reference to the originating sock by restoring skb->sk
252 * after each skb_clone() or skb_orphan() usage.
255 if (!(skb->dev->flags & IFF_ECHO)) {
256 /* If the interface is not capable to do loopback
257 * itself, we do it here.
259 newskb = skb_clone(skb, GFP_ATOMIC);
265 can_skb_set_owner(newskb, skb->sk);
266 newskb->ip_summed = CHECKSUM_UNNECESSARY;
267 newskb->pkt_type = PACKET_BROADCAST;
270 /* indication for the CAN driver: no loopback required */
271 skb->pkt_type = PACKET_HOST;
274 /* send to netdevice */
275 err = dev_queue_xmit(skb);
277 err = net_xmit_errno(err);
287 /* update statistics */
288 can_stats->tx_frames++;
289 can_stats->tx_frames_delta++;
297 EXPORT_SYMBOL(can_send);
301 static struct can_dev_rcv_lists *find_dev_rcv_lists(struct net *net,
302 struct net_device *dev)
305 return net->can.can_rx_alldev_list;
307 return (struct can_dev_rcv_lists *)dev->ml_priv;
311 * effhash - hash function for 29 bit CAN identifier reduction
312 * @can_id: 29 bit CAN identifier
315 * To reduce the linear traversal in one linked list of _single_ EFF CAN
316 * frame subscriptions the 29 bit identifier is mapped to 10 bits.
317 * (see CAN_EFF_RCV_HASH_BITS definition)
320 * Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask )
322 static unsigned int effhash(canid_t can_id)
327 hash ^= can_id >> CAN_EFF_RCV_HASH_BITS;
328 hash ^= can_id >> (2 * CAN_EFF_RCV_HASH_BITS);
330 return hash & ((1 << CAN_EFF_RCV_HASH_BITS) - 1);
334 * find_rcv_list - determine optimal filterlist inside device filter struct
335 * @can_id: pointer to CAN identifier of a given can_filter
336 * @mask: pointer to CAN mask of a given can_filter
337 * @d: pointer to the device filter struct
340 * Returns the optimal filterlist to reduce the filter handling in the
341 * receive path. This function is called by service functions that need
342 * to register or unregister a can_filter in the filter lists.
344 * A filter matches in general, when
346 * <received_can_id> & mask == can_id & mask
348 * so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe
349 * relevant bits for the filter.
351 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
352 * filter for error messages (CAN_ERR_FLAG bit set in mask). For error msg
353 * frames there is a special filterlist and a special rx path filter handling.
356 * Pointer to optimal filterlist for the given can_id/mask pair.
357 * Constistency checked mask.
358 * Reduced can_id to have a preprocessed filter compare value.
360 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
361 struct can_dev_rcv_lists *d)
363 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
365 /* filter for error message frames in extra filterlist */
366 if (*mask & CAN_ERR_FLAG) {
367 /* clear CAN_ERR_FLAG in filter entry */
368 *mask &= CAN_ERR_MASK;
369 return &d->rx[RX_ERR];
372 /* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */
374 #define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG)
376 /* ensure valid values in can_mask for 'SFF only' frame filtering */
377 if ((*mask & CAN_EFF_FLAG) && !(*can_id & CAN_EFF_FLAG))
378 *mask &= (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS);
380 /* reduce condition testing at receive time */
383 /* inverse can_id/can_mask filter */
385 return &d->rx[RX_INV];
387 /* mask == 0 => no condition testing at receive time */
389 return &d->rx[RX_ALL];
391 /* extra filterlists for the subscription of a single non-RTR can_id */
392 if (((*mask & CAN_EFF_RTR_FLAGS) == CAN_EFF_RTR_FLAGS) &&
393 !(*can_id & CAN_RTR_FLAG)) {
394 if (*can_id & CAN_EFF_FLAG) {
395 if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS))
396 return &d->rx_eff[effhash(*can_id)];
398 if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS))
399 return &d->rx_sff[*can_id];
403 /* default: filter via can_id/can_mask */
404 return &d->rx[RX_FIL];
408 * can_rx_register - subscribe CAN frames from a specific interface
409 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
410 * @can_id: CAN identifier (see description)
411 * @mask: CAN mask (see description)
412 * @func: callback function on filter match
413 * @data: returned parameter for callback function
414 * @ident: string for calling module identification
415 * @sk: socket pointer (might be NULL)
418 * Invokes the callback function with the received sk_buff and the given
419 * parameter 'data' on a matching receive filter. A filter matches, when
421 * <received_can_id> & mask == can_id & mask
423 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
424 * filter for error message frames (CAN_ERR_FLAG bit set in mask).
426 * The provided pointer to the sk_buff is guaranteed to be valid as long as
427 * the callback function is running. The callback function must *not* free
428 * the given sk_buff while processing it's task. When the given sk_buff is
429 * needed after the end of the callback function it must be cloned inside
430 * the callback function with skb_clone().
434 * -ENOMEM on missing cache mem to create subscription entry
435 * -ENODEV unknown device
437 int can_rx_register(struct net *net, struct net_device *dev, canid_t can_id,
438 canid_t mask, void (*func)(struct sk_buff *, void *),
439 void *data, char *ident, struct sock *sk)
442 struct hlist_head *rl;
443 struct can_dev_rcv_lists *d;
444 struct s_pstats *can_pstats = net->can.can_pstats;
447 /* insert new receiver (dev,canid,mask) -> (func,data) */
449 if (dev && dev->type != ARPHRD_CAN)
452 if (dev && !net_eq(net, dev_net(dev)))
455 r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
459 spin_lock(&net->can.can_rcvlists_lock);
461 d = find_dev_rcv_lists(net, dev);
463 rl = find_rcv_list(&can_id, &mask, d);
473 hlist_add_head_rcu(&r->list, rl);
476 can_pstats->rcv_entries++;
477 if (can_pstats->rcv_entries_max < can_pstats->rcv_entries)
478 can_pstats->rcv_entries_max = can_pstats->rcv_entries;
480 kmem_cache_free(rcv_cache, r);
484 spin_unlock(&net->can.can_rcvlists_lock);
488 EXPORT_SYMBOL(can_rx_register);
490 /* can_rx_delete_receiver - rcu callback for single receiver entry removal */
491 static void can_rx_delete_receiver(struct rcu_head *rp)
493 struct receiver *r = container_of(rp, struct receiver, rcu);
494 struct sock *sk = r->sk;
496 kmem_cache_free(rcv_cache, r);
502 * can_rx_unregister - unsubscribe CAN frames from a specific interface
503 * @dev: pointer to netdevice (NULL => unsubscribe from 'all' CAN devices list)
504 * @can_id: CAN identifier
506 * @func: callback function on filter match
507 * @data: returned parameter for callback function
510 * Removes subscription entry depending on given (subscription) values.
512 void can_rx_unregister(struct net *net, struct net_device *dev, canid_t can_id,
513 canid_t mask, void (*func)(struct sk_buff *, void *),
516 struct receiver *r = NULL;
517 struct hlist_head *rl;
518 struct s_pstats *can_pstats = net->can.can_pstats;
519 struct can_dev_rcv_lists *d;
521 if (dev && dev->type != ARPHRD_CAN)
524 if (dev && !net_eq(net, dev_net(dev)))
527 spin_lock(&net->can.can_rcvlists_lock);
529 d = find_dev_rcv_lists(net, dev);
531 pr_err("BUG: receive list not found for dev %s, id %03X, mask %03X\n",
532 DNAME(dev), can_id, mask);
536 rl = find_rcv_list(&can_id, &mask, d);
538 /* Search the receiver list for the item to delete. This should
539 * exist, since no receiver may be unregistered that hasn't
540 * been registered before.
543 hlist_for_each_entry_rcu(r, rl, list) {
544 if (r->can_id == can_id && r->mask == mask &&
545 r->func == func && r->data == data)
549 /* Check for bugs in CAN protocol implementations using af_can.c:
550 * 'r' will be NULL if no matching list item was found for removal.
554 WARN(1, "BUG: receive list entry not found for dev %s, id %03X, mask %03X\n",
555 DNAME(dev), can_id, mask);
559 hlist_del_rcu(&r->list);
562 if (can_pstats->rcv_entries > 0)
563 can_pstats->rcv_entries--;
565 /* remove device structure requested by NETDEV_UNREGISTER */
566 if (d->remove_on_zero_entries && !d->entries) {
572 spin_unlock(&net->can.can_rcvlists_lock);
574 /* schedule the receiver item for deletion */
578 call_rcu(&r->rcu, can_rx_delete_receiver);
581 EXPORT_SYMBOL(can_rx_unregister);
583 static inline void deliver(struct sk_buff *skb, struct receiver *r)
585 r->func(skb, r->data);
589 static int can_rcv_filter(struct can_dev_rcv_lists *d, struct sk_buff *skb)
593 struct can_frame *cf = (struct can_frame *)skb->data;
594 canid_t can_id = cf->can_id;
599 if (can_id & CAN_ERR_FLAG) {
600 /* check for error message frame entries only */
601 hlist_for_each_entry_rcu(r, &d->rx[RX_ERR], list) {
602 if (can_id & r->mask) {
610 /* check for unfiltered entries */
611 hlist_for_each_entry_rcu(r, &d->rx[RX_ALL], list) {
616 /* check for can_id/mask entries */
617 hlist_for_each_entry_rcu(r, &d->rx[RX_FIL], list) {
618 if ((can_id & r->mask) == r->can_id) {
624 /* check for inverted can_id/mask entries */
625 hlist_for_each_entry_rcu(r, &d->rx[RX_INV], list) {
626 if ((can_id & r->mask) != r->can_id) {
632 /* check filterlists for single non-RTR can_ids */
633 if (can_id & CAN_RTR_FLAG)
636 if (can_id & CAN_EFF_FLAG) {
637 hlist_for_each_entry_rcu(r, &d->rx_eff[effhash(can_id)], list) {
638 if (r->can_id == can_id) {
644 can_id &= CAN_SFF_MASK;
645 hlist_for_each_entry_rcu(r, &d->rx_sff[can_id], list) {
654 static void can_receive(struct sk_buff *skb, struct net_device *dev)
656 struct can_dev_rcv_lists *d;
657 struct net *net = dev_net(dev);
658 struct s_stats *can_stats = net->can.can_stats;
661 /* update statistics */
662 can_stats->rx_frames++;
663 can_stats->rx_frames_delta++;
665 /* create non-zero unique skb identifier together with *skb */
666 while (!(can_skb_prv(skb)->skbcnt))
667 can_skb_prv(skb)->skbcnt = atomic_inc_return(&skbcounter);
671 /* deliver the packet to sockets listening on all devices */
672 matches = can_rcv_filter(net->can.can_rx_alldev_list, skb);
674 /* find receive list for this device */
675 d = find_dev_rcv_lists(net, dev);
677 matches += can_rcv_filter(d, skb);
681 /* consume the skbuff allocated by the netdevice driver */
685 can_stats->matches++;
686 can_stats->matches_delta++;
690 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
691 struct packet_type *pt, struct net_device *orig_dev)
693 struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
695 if (unlikely(dev->type != ARPHRD_CAN || skb->len != CAN_MTU ||
696 cfd->len > CAN_MAX_DLEN)) {
697 pr_warn_once("PF_CAN: dropped non conform CAN skbuf: dev type %d, len %d, datalen %d\n",
698 dev->type, skb->len, cfd->len);
703 can_receive(skb, dev);
704 return NET_RX_SUCCESS;
707 static int canfd_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(dev->type != ARPHRD_CAN || skb->len != CANFD_MTU ||
713 cfd->len > CANFD_MAX_DLEN)) {
714 pr_warn_once("PF_CAN: dropped non conform CAN FD skbuf: dev type %d, len %d, datalen %d\n",
715 dev->type, skb->len, cfd->len);
720 can_receive(skb, dev);
721 return NET_RX_SUCCESS;
724 /* af_can protocol functions */
727 * can_proto_register - register CAN transport protocol
728 * @cp: pointer to CAN protocol structure
732 * -EINVAL invalid (out of range) protocol number
733 * -EBUSY protocol already in use
734 * -ENOBUF if proto_register() fails
736 int can_proto_register(const struct can_proto *cp)
738 int proto = cp->protocol;
741 if (proto < 0 || proto >= CAN_NPROTO) {
742 pr_err("can: protocol number %d out of range\n", proto);
746 err = proto_register(cp->prot, 0);
750 mutex_lock(&proto_tab_lock);
752 if (rcu_access_pointer(proto_tab[proto])) {
753 pr_err("can: protocol %d already registered\n", proto);
756 RCU_INIT_POINTER(proto_tab[proto], cp);
759 mutex_unlock(&proto_tab_lock);
762 proto_unregister(cp->prot);
766 EXPORT_SYMBOL(can_proto_register);
769 * can_proto_unregister - unregister CAN transport protocol
770 * @cp: pointer to CAN protocol structure
772 void can_proto_unregister(const struct can_proto *cp)
774 int proto = cp->protocol;
776 mutex_lock(&proto_tab_lock);
777 BUG_ON(rcu_access_pointer(proto_tab[proto]) != cp);
778 RCU_INIT_POINTER(proto_tab[proto], NULL);
779 mutex_unlock(&proto_tab_lock);
783 proto_unregister(cp->prot);
785 EXPORT_SYMBOL(can_proto_unregister);
787 /* af_can notifier to create/remove CAN netdevice specific structs */
788 static int can_notifier(struct notifier_block *nb, unsigned long msg,
791 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
792 struct can_dev_rcv_lists *d;
794 if (dev->type != ARPHRD_CAN)
798 case NETDEV_REGISTER:
800 /* create new dev_rcv_lists for this device */
801 d = kzalloc(sizeof(*d), GFP_KERNEL);
804 BUG_ON(dev->ml_priv);
809 case NETDEV_UNREGISTER:
810 spin_lock(&dev_net(dev)->can.can_rcvlists_lock);
815 d->remove_on_zero_entries = 1;
821 pr_err("can: notifier: receive list not found for dev %s\n",
825 spin_unlock(&dev_net(dev)->can.can_rcvlists_lock);
833 static int can_pernet_init(struct net *net)
835 spin_lock_init(&net->can.can_rcvlists_lock);
836 net->can.can_rx_alldev_list =
837 kzalloc(sizeof(struct can_dev_rcv_lists), GFP_KERNEL);
838 if (!net->can.can_rx_alldev_list)
840 net->can.can_stats = kzalloc(sizeof(struct s_stats), GFP_KERNEL);
841 if (!net->can.can_stats)
842 goto out_free_alldev_list;
843 net->can.can_pstats = kzalloc(sizeof(struct s_pstats), GFP_KERNEL);
844 if (!net->can.can_pstats)
845 goto out_free_can_stats;
847 if (IS_ENABLED(CONFIG_PROC_FS)) {
848 /* the statistics are updated every second (timer triggered) */
850 timer_setup(&net->can.can_stattimer, can_stat_update,
852 mod_timer(&net->can.can_stattimer,
853 round_jiffies(jiffies + HZ));
855 net->can.can_stats->jiffies_init = jiffies;
862 kfree(net->can.can_stats);
863 out_free_alldev_list:
864 kfree(net->can.can_rx_alldev_list);
869 static void can_pernet_exit(struct net *net)
871 struct net_device *dev;
873 if (IS_ENABLED(CONFIG_PROC_FS)) {
874 can_remove_proc(net);
876 del_timer_sync(&net->can.can_stattimer);
879 /* remove created dev_rcv_lists from still registered CAN devices */
881 for_each_netdev_rcu(net, dev) {
882 if (dev->type == ARPHRD_CAN && dev->ml_priv) {
883 struct can_dev_rcv_lists *d = dev->ml_priv;
892 kfree(net->can.can_rx_alldev_list);
893 kfree(net->can.can_stats);
894 kfree(net->can.can_pstats);
897 /* af_can module init/exit functions */
899 static struct packet_type can_packet __read_mostly = {
900 .type = cpu_to_be16(ETH_P_CAN),
904 static struct packet_type canfd_packet __read_mostly = {
905 .type = cpu_to_be16(ETH_P_CANFD),
909 static const struct net_proto_family can_family_ops = {
911 .create = can_create,
912 .owner = THIS_MODULE,
915 /* notifier block for netdevice event */
916 static struct notifier_block can_netdev_notifier __read_mostly = {
917 .notifier_call = can_notifier,
920 static struct pernet_operations can_pernet_ops __read_mostly = {
921 .init = can_pernet_init,
922 .exit = can_pernet_exit,
925 static __init int can_init(void)
929 /* check for correct padding to be able to use the structs similarly */
930 BUILD_BUG_ON(offsetof(struct can_frame, can_dlc) !=
931 offsetof(struct canfd_frame, len) ||
932 offsetof(struct can_frame, data) !=
933 offsetof(struct canfd_frame, data));
935 pr_info("can: controller area network core (" CAN_VERSION_STRING ")\n");
937 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
942 err = register_pernet_subsys(&can_pernet_ops);
946 /* protocol register */
947 err = sock_register(&can_family_ops);
950 err = register_netdevice_notifier(&can_netdev_notifier);
954 dev_add_pack(&can_packet);
955 dev_add_pack(&canfd_packet);
960 sock_unregister(PF_CAN);
962 unregister_pernet_subsys(&can_pernet_ops);
964 kmem_cache_destroy(rcv_cache);
969 static __exit void can_exit(void)
971 /* protocol unregister */
972 dev_remove_pack(&canfd_packet);
973 dev_remove_pack(&can_packet);
974 unregister_netdevice_notifier(&can_netdev_notifier);
975 sock_unregister(PF_CAN);
977 unregister_pernet_subsys(&can_pernet_ops);
979 rcu_barrier(); /* Wait for completion of call_rcu()'s */
981 kmem_cache_destroy(rcv_cache);
984 module_init(can_init);
985 module_exit(can_exit);