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
41 * Send feedback to <socketcan-users@lists.berlios.de>
45 #include <linux/module.h>
46 #include <linux/version.h>
47 #include <linux/init.h>
48 #include <linux/kmod.h>
49 #include <linux/slab.h>
50 #include <linux/list.h>
51 #include <linux/spinlock.h>
52 #include <linux/rcupdate.h>
53 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,18)
54 #include <linux/uaccess.h>
56 #include <asm/uaccess.h>
58 #include <linux/net.h>
59 #include <linux/netdevice.h>
60 #include <linux/socket.h>
61 #include <linux/if_ether.h>
62 #include <linux/if_arp.h>
63 #include <linux/skbuff.h>
64 #include <linux/can.h>
65 #include <linux/can/core.h>
66 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
67 #include <net/net_namespace.h>
72 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
76 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
79 static __initdata const char banner[] = KERN_INFO
80 "can: controller area network core (" CAN_VERSION_STRING ")\n";
82 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
83 MODULE_LICENSE("Dual BSD/GPL");
84 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
85 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
87 MODULE_ALIAS_NETPROTO(PF_CAN);
89 static int stats_timer __read_mostly = 1;
90 module_param(stats_timer, int, S_IRUGO);
91 MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
93 HLIST_HEAD(can_rx_dev_list);
94 static struct dev_rcv_lists can_rx_alldev_list;
95 static DEFINE_SPINLOCK(can_rcvlists_lock);
97 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
98 static struct kmem_cache *rcv_cache __read_mostly;
100 static kmem_cache_t *rcv_cache;
103 /* table of registered CAN protocols */
104 static struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
105 static DEFINE_SPINLOCK(proto_tab_lock);
107 struct timer_list can_stattimer; /* timer for statistics update */
108 struct s_stats can_stats; /* packet statistics */
109 struct s_pstats can_pstats; /* receive list statistics */
112 * af_can socket functions
115 static int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
117 struct sock *sk = sock->sk;
122 return sock_get_timestamp(sk, (struct timeval __user *)arg);
125 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
128 return dev_ioctl(cmd, (void __user *)arg);
133 static void can_sock_destruct(struct sock *sk)
135 skb_queue_purge(&sk->sk_receive_queue);
136 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
138 kfree(sk->sk_protinfo);
142 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
143 static int can_create(struct net *net, struct socket *sock, int protocol)
145 static int can_create(struct socket *sock, int protocol)
149 struct can_proto *cp;
152 sock->state = SS_UNCONNECTED;
154 if (protocol < 0 || protocol >= CAN_NPROTO)
157 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
158 if (net != &init_net)
159 return -EAFNOSUPPORT;
163 /* try to load protocol module, when CONFIG_KMOD is defined */
164 if (!proto_tab[protocol]) {
165 err = request_module("can-proto-%d", protocol);
168 * In case of error we only print a message but don't
169 * return the error code immediately. Below we will
170 * return -EPROTONOSUPPORT
172 if (err && printk_ratelimit())
173 printk(KERN_ERR "can: request_module "
174 "(can-proto-%d) failed.\n", protocol);
178 spin_lock(&proto_tab_lock);
179 cp = proto_tab[protocol];
180 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
181 if (cp && !try_module_get(cp->prot->owner))
184 if (cp && !try_module_get(cp->owner))
187 spin_unlock(&proto_tab_lock);
189 /* check for available protocol and correct usage */
192 return -EPROTONOSUPPORT;
194 if (cp->type != sock->type) {
195 err = -EPROTONOSUPPORT;
199 if (cp->capability >= 0 && !capable(cp->capability)) {
206 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
207 sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
208 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
209 sk = sk_alloc(PF_CAN, GFP_KERNEL, cp->prot, 1);
211 sk = sk_alloc(PF_CAN, GFP_KERNEL, 1, 0);
218 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
220 sk->sk_protinfo = kmalloc(cp->obj_size, GFP_KERNEL);
221 if (!sk->sk_protinfo) {
227 sk_set_owner(sk, proto_tab[protocol]->owner);
230 sock_init_data(sock, sk);
231 sk->sk_destruct = can_sock_destruct;
233 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
234 if (sk->sk_prot->init)
235 err = sk->sk_prot->init(sk);
242 /* release sk on errors */
248 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
249 module_put(cp->prot->owner);
251 module_put(cp->owner);
261 * can_send - transmit a CAN frame (optional with local loopback)
262 * @skb: pointer to socket buffer with CAN frame in data section
263 * @loop: loopback for listeners on local CAN sockets (recommended default!)
267 * -ENETDOWN when the selected interface is down
268 * -ENOBUFS on full driver queue (see net_xmit_errno())
269 * -ENOMEM when local loopback failed at calling skb_clone()
270 * -EPERM when trying to send on a non-CAN interface
272 int can_send(struct sk_buff *skb, int loop)
276 if (skb->dev->type != ARPHRD_CAN) {
281 if (!(skb->dev->flags & IFF_UP)) {
286 skb->protocol = htons(ETH_P_CAN);
287 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
288 skb_reset_network_header(skb);
289 skb_reset_transport_header(skb);
291 skb->nh.raw = skb->data;
292 skb->h.raw = skb->data;
296 /* local loopback of sent CAN frames */
298 /* indication for the CAN driver: do loopback */
299 skb->pkt_type = PACKET_LOOPBACK;
302 * The reference to the originating sock may be required
303 * by the receiving socket to check whether the frame is
304 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
305 * Therefore we have to ensure that skb->sk remains the
306 * reference to the originating sock by restoring skb->sk
307 * after each skb_clone() or skb_orphan() usage.
310 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
311 #define IFF_ECHO IFF_LOOPBACK
313 if (!(skb->dev->flags & IFF_ECHO)) {
315 * If the interface is not capable to do loopback
316 * itself, we do it here.
318 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
325 newskb->sk = skb->sk;
326 newskb->ip_summed = CHECKSUM_UNNECESSARY;
327 newskb->pkt_type = PACKET_BROADCAST;
331 /* indication for the CAN driver: no loopback required */
332 skb->pkt_type = PACKET_HOST;
335 /* send to netdevice */
336 err = dev_queue_xmit(skb);
338 err = net_xmit_errno(err);
340 /* update statistics */
341 can_stats.tx_frames++;
342 can_stats.tx_frames_delta++;
346 EXPORT_SYMBOL(can_send);
352 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
354 struct dev_rcv_lists *d = NULL;
355 struct hlist_node *n;
358 * find receive list for this device
360 * The hlist_for_each_entry*() macros curse through the list
361 * using the pointer variable n and set d to the containing
362 * struct in each list iteration. Therefore, after list
363 * iteration, d is unmodified when the list is empty, and it
364 * points to last list element, when the list is non-empty
365 * but no match in the loop body is found. I.e. d is *not*
366 * NULL when no match is found. We can, however, use the
367 * cursor variable n to decide if a match was found.
370 hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
378 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
379 struct dev_rcv_lists *d)
381 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
383 /* filter error frames */
384 if (*mask & CAN_ERR_FLAG) {
385 /* clear CAN_ERR_FLAG in list entry */
386 *mask &= CAN_ERR_MASK;
387 return &d->rx[RX_ERR];
390 /* ensure valid values in can_mask */
391 if (*mask & CAN_EFF_FLAG)
392 *mask &= (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG);
394 *mask &= (CAN_SFF_MASK | CAN_RTR_FLAG);
396 /* reduce condition testing at receive time */
399 /* inverse can_id/can_mask filter */
401 return &d->rx[RX_INV];
403 /* mask == 0 => no condition testing at receive time */
405 return &d->rx[RX_ALL];
407 /* use extra filterset for the subscription of exactly *ONE* can_id */
408 if (*can_id & CAN_EFF_FLAG) {
409 if (*mask == (CAN_EFF_MASK | CAN_EFF_FLAG)) {
410 /* RFC: a use-case for hash-tables in the future? */
411 return &d->rx[RX_EFF];
414 if (*mask == CAN_SFF_MASK)
415 return &d->rx_sff[*can_id];
418 /* default: filter via can_id/can_mask */
419 return &d->rx[RX_FIL];
423 * can_rx_register - subscribe CAN frames from a specific interface
424 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
425 * @can_id: CAN identifier (see description)
426 * @mask: CAN mask (see description)
427 * @func: callback function on filter match
428 * @data: returned parameter for callback function
429 * @ident: string for calling module indentification
432 * Invokes the callback function with the received sk_buff and the given
433 * parameter 'data' on a matching receive filter. A filter matches, when
435 * <received_can_id> & mask == can_id & mask
437 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
438 * filter for error frames (CAN_ERR_FLAG bit set in mask).
442 * -ENOMEM on missing cache mem to create subscription entry
443 * -ENODEV unknown device
445 int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
446 void (*func)(struct sk_buff *, void *), void *data,
450 struct hlist_head *rl;
451 struct dev_rcv_lists *d;
454 /* insert new receiver (dev,canid,mask) -> (func,data) */
456 r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
460 spin_lock(&can_rcvlists_lock);
462 d = find_dev_rcv_lists(dev);
464 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(&can_rcvlists_lock);
488 EXPORT_SYMBOL(can_rx_register);
491 * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
493 static void can_rx_delete_device(struct rcu_head *rp)
495 struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
501 * can_rx_delete_receiver - rcu callback for single receiver entry removal
503 static void can_rx_delete_receiver(struct rcu_head *rp)
505 struct receiver *r = container_of(rp, struct receiver, rcu);
507 kmem_cache_free(rcv_cache, r);
511 * can_rx_unregister - unsubscribe CAN frames from a specific interface
512 * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
513 * @can_id: CAN identifier
515 * @func: callback function on filter match
516 * @data: returned parameter for callback function
519 * Removes subscription entry depending on given (subscription) values.
521 void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
522 void (*func)(struct sk_buff *, void *), void *data)
524 struct receiver *r = NULL;
525 struct hlist_head *rl;
526 struct hlist_node *next;
527 struct dev_rcv_lists *d;
529 spin_lock(&can_rcvlists_lock);
531 d = find_dev_rcv_lists(dev);
533 printk(KERN_ERR "BUG: receive list not found for "
534 "dev %s, id %03X, mask %03X\n",
535 DNAME(dev), can_id, mask);
539 rl = find_rcv_list(&can_id, &mask, d);
542 * Search the receiver list for the item to delete. This should
543 * exist, since no receiver may be unregistered that hasn't
544 * been registered before.
547 hlist_for_each_entry_rcu(r, next, rl, list) {
548 if (r->can_id == can_id && r->mask == mask
549 && r->func == func && r->data == data)
554 * Check for bugs in CAN protocol implementations:
555 * If no matching list item was found, the list cursor variable next
556 * will be NULL, while r will point to the last item of the list.
560 printk(KERN_ERR "BUG: receive list entry not found for "
561 "dev %s, id %03X, mask %03X\n",
562 DNAME(dev), can_id, mask);
568 hlist_del_rcu(&r->list);
571 if (can_pstats.rcv_entries > 0)
572 can_pstats.rcv_entries--;
574 /* remove device structure requested by NETDEV_UNREGISTER */
575 if (d->remove_on_zero_entries && !d->entries)
576 hlist_del_rcu(&d->list);
581 spin_unlock(&can_rcvlists_lock);
583 /* schedule the receiver item for deletion */
585 call_rcu(&r->rcu, can_rx_delete_receiver);
587 /* schedule the device structure for deletion */
589 call_rcu(&d->rcu, can_rx_delete_device);
591 EXPORT_SYMBOL(can_rx_unregister);
593 static inline void deliver(struct sk_buff *skb, struct receiver *r)
595 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
599 r->func(clone, r->data);
604 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
607 struct hlist_node *n;
609 struct can_frame *cf = (struct can_frame *)skb->data;
610 canid_t can_id = cf->can_id;
615 if (can_id & CAN_ERR_FLAG) {
616 /* check for error frame entries only */
617 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ERR], list) {
618 if (can_id & r->mask) {
626 /* check for unfiltered entries */
627 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ALL], list) {
632 /* check for can_id/mask entries */
633 hlist_for_each_entry_rcu(r, n, &d->rx[RX_FIL], list) {
634 if ((can_id & r->mask) == r->can_id) {
640 /* check for inverted can_id/mask entries */
641 hlist_for_each_entry_rcu(r, n, &d->rx[RX_INV], list) {
642 if ((can_id & r->mask) != r->can_id) {
648 /* check CAN_ID specific entries */
649 if (can_id & CAN_EFF_FLAG) {
650 hlist_for_each_entry_rcu(r, n, &d->rx[RX_EFF], list) {
651 if (r->can_id == can_id) {
657 can_id &= CAN_SFF_MASK;
658 hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
667 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
668 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
669 struct packet_type *pt, struct net_device *orig_dev)
671 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
672 struct packet_type *pt)
675 struct dev_rcv_lists *d;
678 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
679 if (dev->type != ARPHRD_CAN || dev->nd_net != &init_net) {
681 if (dev->type != ARPHRD_CAN) {
687 /* update statistics */
688 can_stats.rx_frames++;
689 can_stats.rx_frames_delta++;
693 /* deliver the packet to sockets listening on all devices */
694 matches = can_rcv_filter(&can_rx_alldev_list, skb);
696 /* find receive list for this device */
697 d = find_dev_rcv_lists(dev);
699 matches += can_rcv_filter(d, skb);
703 /* free the skbuff allocated by the netdevice driver */
708 can_stats.matches_delta++;
715 * af_can protocol functions
719 * can_proto_register - register CAN transport protocol
720 * @cp: pointer to CAN protocol structure
724 * -EINVAL invalid (out of range) protocol number
725 * -EBUSY protocol already in use
726 * -ENOBUF if proto_register() fails
728 int can_proto_register(struct can_proto *cp)
730 int proto = cp->protocol;
733 if (proto < 0 || proto >= CAN_NPROTO) {
734 printk(KERN_ERR "can: protocol number %d out of range\n",
739 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
740 err = proto_register(cp->prot, 0);
745 spin_lock(&proto_tab_lock);
746 if (proto_tab[proto]) {
747 printk(KERN_ERR "can: protocol %d already registered\n",
751 proto_tab[proto] = cp;
753 /* use generic ioctl function if not defined by module */
755 cp->ops->ioctl = can_ioctl;
757 spin_unlock(&proto_tab_lock);
759 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
761 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(struct can_proto *cp)
774 int proto = cp->protocol;
776 spin_lock(&proto_tab_lock);
777 if (!proto_tab[proto]) {
778 printk(KERN_ERR "BUG: can: protocol %d is not registered\n",
781 proto_tab[proto] = NULL;
782 spin_unlock(&proto_tab_lock);
784 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
785 proto_unregister(cp->prot);
788 EXPORT_SYMBOL(can_proto_unregister);
791 * af_can notifier to create/remove CAN netdevice specific structs
793 static int can_notifier(struct notifier_block *nb, unsigned long msg,
796 struct net_device *dev = (struct net_device *)data;
797 struct dev_rcv_lists *d;
799 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
800 if (dev->nd_net != &init_net)
804 if (dev->type != ARPHRD_CAN)
809 case NETDEV_REGISTER:
812 * create new dev_rcv_lists for this device
814 * N.B. zeroing the struct is the correct initialization
815 * for the embedded hlist_head structs.
816 * Another list type, e.g. list_head, would require
817 * explicit initialization.
820 d = kzalloc(sizeof(*d), GFP_KERNEL);
823 "can: allocation of receive list failed\n");
828 spin_lock(&can_rcvlists_lock);
829 hlist_add_head_rcu(&d->list, &can_rx_dev_list);
830 spin_unlock(&can_rcvlists_lock);
834 case NETDEV_UNREGISTER:
835 spin_lock(&can_rcvlists_lock);
837 d = find_dev_rcv_lists(dev);
840 d->remove_on_zero_entries = 1;
843 hlist_del_rcu(&d->list);
845 printk(KERN_ERR "can: notifier: receive list not "
846 "found for dev %s\n", dev->name);
848 spin_unlock(&can_rcvlists_lock);
851 call_rcu(&d->rcu, can_rx_delete_device);
860 * af_can module init/exit functions
863 static struct packet_type can_packet __read_mostly = {
864 .type = __constant_htons(ETH_P_CAN),
869 static struct net_proto_family can_family_ops __read_mostly = {
871 .create = can_create,
872 .owner = THIS_MODULE,
875 /* notifier block for netdevice event */
876 static struct notifier_block can_netdev_notifier __read_mostly = {
877 .notifier_call = can_notifier,
880 static __init int can_init(void)
884 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
885 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
888 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
895 * Insert can_rx_alldev_list for reception on all devices.
896 * This struct is zero initialized which is correct for the
897 * embedded hlist heads, the dev pointer, and the entries counter.
900 spin_lock(&can_rcvlists_lock);
901 hlist_add_head_rcu(&can_rx_alldev_list.list, &can_rx_dev_list);
902 spin_unlock(&can_rcvlists_lock);
905 /* the statistics are updated every second (timer triggered) */
906 setup_timer(&can_stattimer, can_stat_update, 0);
907 mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
909 can_stattimer.function = NULL;
913 /* protocol register */
914 sock_register(&can_family_ops);
915 register_netdevice_notifier(&can_netdev_notifier);
916 dev_add_pack(&can_packet);
921 static __exit void can_exit(void)
923 struct dev_rcv_lists *d;
924 struct hlist_node *n, *next;
927 del_timer(&can_stattimer);
931 /* protocol unregister */
932 dev_remove_pack(&can_packet);
933 unregister_netdevice_notifier(&can_netdev_notifier);
934 sock_unregister(PF_CAN);
936 /* remove can_rx_dev_list */
937 spin_lock(&can_rcvlists_lock);
938 hlist_del(&can_rx_alldev_list.list);
939 hlist_for_each_entry_safe(d, n, next, &can_rx_dev_list, list) {
943 spin_unlock(&can_rcvlists_lock);
945 kmem_cache_destroy(rcv_cache);
948 module_init(can_init);
949 module_exit(can_exit);