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, the following disclaimer and
13 * the referenced file 'COPYING'.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of Volkswagen nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * Alternatively, provided that this notice is retained in full, this
22 * software may be distributed under the terms of the GNU General
23 * Public License ("GPL") version 2 as distributed in the 'COPYING'
24 * file from the main directory of the linux kernel source.
26 * The provided data structures and external interfaces from this code
27 * are not restricted to be used by modules with a GPL compatible license.
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
42 * Send feedback to <socketcan-users@lists.berlios.de>
46 #include <linux/module.h>
47 #include <linux/version.h>
48 #include <linux/init.h>
49 #include <linux/kmod.h>
50 #include <linux/slab.h>
51 #include <linux/list.h>
52 #include <linux/spinlock.h>
53 #include <linux/rcupdate.h>
54 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,18)
55 #include <linux/uaccess.h>
57 #include <asm/uaccess.h>
59 #include <linux/net.h>
60 #include <linux/netdevice.h>
61 #include <linux/socket.h>
62 #include <linux/if_ether.h>
63 #include <linux/if_arp.h>
64 #include <linux/skbuff.h>
65 #include <linux/can.h>
66 #include <linux/can/core.h>
67 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
68 #include <net/net_namespace.h>
74 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
78 static __initdata const char banner[] = KERN_INFO
79 "can: controller area network core (" CAN_VERSION_STRING ")\n";
81 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
82 MODULE_LICENSE("Dual BSD/GPL");
83 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
84 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
86 MODULE_ALIAS_NETPROTO(PF_CAN);
88 static int stats_timer __read_mostly = 1;
89 module_param(stats_timer, int, S_IRUGO);
90 MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
92 #ifdef CONFIG_CAN_DEBUG_CORE
93 static int debug __read_mostly;
94 module_param(debug, int, S_IRUGO);
95 MODULE_PARM_DESC(debug, "debug print mask: 1:debug, 2:frames, 4:skbs");
98 HLIST_HEAD(rx_dev_list);
99 static struct dev_rcv_lists rx_alldev_list;
100 static DEFINE_SPINLOCK(rcv_lists_lock);
102 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
103 static struct kmem_cache *rcv_cache __read_mostly;
105 static kmem_cache_t *rcv_cache;
108 /* table of registered CAN protocols */
109 static struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
110 static DEFINE_SPINLOCK(proto_tab_lock);
112 struct timer_list stattimer; /* timer for statistics update */
113 struct s_stats stats; /* packet statistics */
114 struct s_pstats pstats; /* receive list statistics */
116 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,14)
117 static void *kzalloc(size_t size, unsigned int __nocast flags)
119 void *ret = kmalloc(size, flags);
121 memset(ret, 0, size);
127 * af_can socket functions
130 static int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
132 struct sock *sk = sock->sk;
137 return sock_get_timestamp(sk, (struct timeval __user *)arg);
140 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
143 return dev_ioctl(cmd, (void __user *)arg);
148 static void can_sock_destruct(struct sock *sk)
150 DBG("called for sock %p\n", sk);
152 skb_queue_purge(&sk->sk_receive_queue);
154 kfree(sk->sk_protinfo);
157 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
158 static int can_create(struct net *net, struct socket *sock, int protocol)
160 static int can_create(struct socket *sock, int protocol)
164 struct can_proto *cp;
165 char module_name[sizeof("can-proto-000")];
168 DBG("socket %p, type %d, proto %d\n", sock, sock->type, protocol);
170 sock->state = SS_UNCONNECTED;
172 if (protocol < 0 || protocol >= CAN_NPROTO)
175 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
176 if (net != &init_net)
177 return -EAFNOSUPPORT;
180 DBG("looking up proto %d in proto_tab[]\n", protocol);
182 /* try to load protocol module, when CONFIG_KMOD is defined */
183 if (!proto_tab[protocol]) {
184 sprintf(module_name, "can-proto-%d", protocol);
185 ret = request_module(module_name);
188 * In case of error we only print a message but don't
189 * return the error code immediately. Below we will
190 * return -EPROTONOSUPPORT
192 if (ret == -ENOSYS) {
193 if (printk_ratelimit())
194 printk(KERN_INFO "can: request_module(%s)"
195 " not implemented.\n", module_name);
197 if (printk_ratelimit())
198 printk(KERN_ERR "can: request_module(%s)"
199 " failed.\n", module_name);
203 spin_lock(&proto_tab_lock);
204 cp = proto_tab[protocol];
205 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
206 if (cp && !try_module_get(cp->prot->owner))
209 if (cp && !try_module_get(cp->owner))
212 spin_unlock(&proto_tab_lock);
214 /* check for success and correct type */
215 if (!cp || cp->type != sock->type) {
216 ret = -EPROTONOSUPPORT;
220 if (cp->capability >= 0 && !capable(cp->capability)) {
227 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
228 sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot, 1);
229 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
230 sk = sk_alloc(PF_CAN, GFP_KERNEL, cp->prot, 1);
232 sk = sk_alloc(PF_CAN, GFP_KERNEL, 1, 0);
239 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
241 sk->sk_protinfo = kmalloc(cp->obj_size, GFP_KERNEL);
242 if (!sk->sk_protinfo) {
248 sk_set_owner(sk, proto_tab[protocol]->owner);
251 sock_init_data(sock, sk);
252 sk->sk_destruct = can_sock_destruct;
254 DBG("created sock: %p\n", sk);
256 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
257 if (sk->sk_prot->init)
258 ret = sk->sk_prot->init(sk);
265 /* release sk on errors */
271 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
272 module_put(cp->prot->owner);
274 module_put(cp->owner);
284 * can_send - transmit a CAN frame (optional with local loopback)
285 * @skb: pointer to socket buffer with CAN frame in data section
286 * @loop: loopback for listeners on local CAN sockets (recommended default!)
290 * -ENETDOWN when the selected interface is down
291 * -ENOBUFS on full driver queue (see net_xmit_errno())
292 * -ENOMEM when local loopback failed at calling skb_clone()
293 * -EPERM when trying to send on a non-CAN interface
295 int can_send(struct sk_buff *skb, int loop)
299 if (skb->dev->type != ARPHRD_CAN) {
304 if (!(skb->dev->flags & IFF_UP)) {
309 skb->protocol = htons(ETH_P_CAN);
312 /* local loopback of sent CAN frames */
314 /* indication for the CAN driver: do loopback */
315 skb->pkt_type = PACKET_LOOPBACK;
318 * The reference to the originating sock may be required
319 * by the receiving socket to check whether the frame is
320 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
321 * Therefore we have to ensure that skb->sk remains the
322 * reference to the originating sock by restoring skb->sk
323 * after each skb_clone() or skb_orphan() usage.
326 if (!(skb->dev->flags & IFF_LOOPBACK)) {
328 * If the interface is not capable to do loopback
329 * itself, we do it here.
331 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
338 newskb->sk = skb->sk;
339 newskb->ip_summed = CHECKSUM_UNNECESSARY;
340 newskb->pkt_type = PACKET_BROADCAST;
344 /* indication for the CAN driver: no loopback required */
345 skb->pkt_type = PACKET_HOST;
348 /* send to netdevice */
349 err = dev_queue_xmit(skb);
351 err = net_xmit_errno(err);
353 /* update statistics */
355 stats.tx_frames_delta++;
359 EXPORT_SYMBOL(can_send);
365 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
367 struct dev_rcv_lists *d;
368 struct hlist_node *n;
371 * find receive list for this device
373 * The hlist_for_each_entry*() macros curse through the list
374 * using the pointer variable n and set d to the containing
375 * struct in each list iteration. Therefore, after list
376 * iteration, d is unmodified when the list is empty, and it
377 * points to last list element, when the list is non-empty
378 * but no match in the loop body is found. I.e. d is *not*
379 * NULL when no match is found. We can, however, use the
380 * cursor variable n to decide if a match was found.
383 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
391 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
392 struct dev_rcv_lists *d)
394 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
396 /* filter error frames */
397 if (*mask & CAN_ERR_FLAG) {
398 /* clear CAN_ERR_FLAG in list entry */
399 *mask &= CAN_ERR_MASK;
400 return &d->rx[RX_ERR];
403 /* ensure valid values in can_mask */
404 if (*mask & CAN_EFF_FLAG)
405 *mask &= (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG);
407 *mask &= (CAN_SFF_MASK | CAN_RTR_FLAG);
409 /* reduce condition testing at receive time */
412 /* inverse can_id/can_mask filter */
414 return &d->rx[RX_INV];
416 /* mask == 0 => no condition testing at receive time */
418 return &d->rx[RX_ALL];
420 /* use extra filterset for the subscription of exactly *ONE* can_id */
421 if (*can_id & CAN_EFF_FLAG) {
422 if (*mask == (CAN_EFF_MASK | CAN_EFF_FLAG)) {
423 /* RFC: a use-case for hash-tables in the future? */
424 return &d->rx[RX_EFF];
427 if (*mask == CAN_SFF_MASK)
428 return &d->rx_sff[*can_id];
431 /* default: filter via can_id/can_mask */
432 return &d->rx[RX_FIL];
436 * can_rx_register - subscribe CAN frames from a specific interface
437 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
438 * @can_id: CAN identifier (see description)
439 * @mask: CAN mask (see description)
440 * @func: callback function on filter match
441 * @data: returned parameter for callback function
442 * @ident: string for calling module indentification
445 * Invokes the callback function with the received sk_buff and the given
446 * parameter 'data' on a matching receive filter. A filter matches, when
448 * <received_can_id> & mask == can_id & mask
450 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
451 * filter for error frames (CAN_ERR_FLAG bit set in mask).
455 * -ENOMEM on missing cache mem to create subscription entry
456 * -ENODEV unknown device
458 int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
459 void (*func)(struct sk_buff *, void *), void *data,
463 struct hlist_head *rl;
464 struct dev_rcv_lists *d;
467 /* insert new receiver (dev,canid,mask) -> (func,data) */
469 DBG("dev %p (%s), id %03X, mask %03X, callback %p, data %p, "
470 "ident %s\n", dev, DNAME(dev), can_id, mask, func, data, ident);
472 r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
476 spin_lock(&rcv_lists_lock);
478 d = find_dev_rcv_lists(dev);
480 rl = find_rcv_list(&can_id, &mask, d);
489 hlist_add_head_rcu(&r->list, rl);
492 pstats.rcv_entries++;
493 if (pstats.rcv_entries_max < pstats.rcv_entries)
494 pstats.rcv_entries_max = pstats.rcv_entries;
496 DBG("receive list not found for dev %s, id %03X, mask %03X\n",
497 DNAME(dev), can_id, mask);
498 kmem_cache_free(rcv_cache, r);
502 spin_unlock(&rcv_lists_lock);
506 EXPORT_SYMBOL(can_rx_register);
509 * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
511 static void can_rx_delete_device(struct rcu_head *rp)
513 struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
515 DBG("removing dev_rcv_list at %p\n", d);
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 DBG("removing receiver at %p\n", r);
527 kmem_cache_free(rcv_cache, r);
531 * can_rx_unregister - unsubscribe CAN frames from a specific interface
532 * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
533 * @can_id: CAN identifier
535 * @func: callback function on filter match
536 * @data: returned parameter for callback function
539 * Removes subscription entry depending on given (subscription) values.
541 void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
542 void (*func)(struct sk_buff *, void *), void *data)
544 struct receiver *r = NULL;
545 struct hlist_head *rl;
546 struct hlist_node *next;
547 struct dev_rcv_lists *d;
549 DBG("dev %p (%s), id %03X, mask %03X, callback %p, data %p\n",
550 dev, DNAME(dev), can_id, mask, func, data);
552 spin_lock(&rcv_lists_lock);
554 d = find_dev_rcv_lists(dev);
556 printk(KERN_ERR "BUG: receive list not found for "
557 "dev %s, id %03X, mask %03X\n",
558 DNAME(dev), can_id, mask);
562 rl = find_rcv_list(&can_id, &mask, d);
565 * Search the receiver list for the item to delete. This should
566 * exist, since no receiver may be unregistered that hasn't
567 * been registered before.
570 hlist_for_each_entry_rcu(r, next, rl, list) {
571 if (r->can_id == can_id && r->mask == mask
572 && r->func == func && r->data == data)
577 * Check for bug in CAN protocol implementations:
578 * If no matching list item was found, the list cursor variable next
579 * will be NULL, while r will point to the last item of the list.
583 printk(KERN_ERR "BUG: receive list entry not found for "
584 "dev %s, id %03X, mask %03X\n",
585 DNAME(dev), can_id, mask);
591 hlist_del_rcu(&r->list);
594 if (pstats.rcv_entries > 0)
595 pstats.rcv_entries--;
597 /* remove device structure requested by NETDEV_UNREGISTER */
598 if (d->remove_on_zero_entries && !d->entries) {
599 DBG("removing dev_rcv_list for %s on zero entries\n",
601 hlist_del_rcu(&d->list);
606 spin_unlock(&rcv_lists_lock);
608 /* schedule the receiver item for deletion */
610 call_rcu(&r->rcu, can_rx_delete_receiver);
612 /* schedule the device structure for deletion */
614 call_rcu(&d->rcu, can_rx_delete_device);
616 EXPORT_SYMBOL(can_rx_unregister);
618 static inline void deliver(struct sk_buff *skb, struct receiver *r)
620 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
622 DBG("skbuff %p cloned to %p\n", skb, clone);
625 r->func(clone, r->data);
630 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
633 struct hlist_node *n;
635 struct can_frame *cf = (struct can_frame *)skb->data;
636 canid_t can_id = cf->can_id;
641 if (can_id & CAN_ERR_FLAG) {
642 /* check for error frame entries only */
643 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ERR], list) {
644 if (can_id & r->mask) {
645 DBG("match on rx_err skbuff %p\n", skb);
653 /* check for unfiltered entries */
654 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ALL], list) {
655 DBG("match on rx_all skbuff %p\n", skb);
660 /* check for can_id/mask entries */
661 hlist_for_each_entry_rcu(r, n, &d->rx[RX_FIL], list) {
662 if ((can_id & r->mask) == r->can_id) {
663 DBG("match on rx_fil skbuff %p\n", skb);
669 /* check for inverted can_id/mask entries */
670 hlist_for_each_entry_rcu(r, n, &d->rx[RX_INV], list) {
671 if ((can_id & r->mask) != r->can_id) {
672 DBG("match on rx_inv skbuff %p\n", skb);
678 /* check CAN_ID specific entries */
679 if (can_id & CAN_EFF_FLAG) {
680 hlist_for_each_entry_rcu(r, n, &d->rx[RX_EFF], list) {
681 if (r->can_id == can_id) {
682 DBG("match on rx_eff skbuff %p\n", skb);
688 can_id &= CAN_SFF_MASK;
689 hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
690 DBG("match on rx_sff skbuff %p\n", skb);
699 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
700 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
701 struct packet_type *pt, struct net_device *orig_dev)
703 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
704 struct packet_type *pt)
707 struct dev_rcv_lists *d;
710 DBG("received skbuff on device %s, ptype %04x\n",
711 dev->name, ntohs(pt->type));
713 DBG_FRAME("af_can: can_rcv: received CAN frame",
714 (struct can_frame *)skb->data);
716 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
717 if (dev->type != ARPHRD_CAN || dev->nd_net != &init_net) {
719 if (dev->type != ARPHRD_CAN) {
725 /* update statistics */
727 stats.rx_frames_delta++;
731 /* deliver the packet to sockets listening on all devices */
732 matches = can_rcv_filter(&rx_alldev_list, skb);
734 /* find receive list for this device */
735 d = find_dev_rcv_lists(dev);
737 matches += can_rcv_filter(d, skb);
741 /* free the skbuff allocated by the netdevice driver */
742 DBG("freeing skbuff %p\n", skb);
747 stats.matches_delta++;
754 * af_can protocol functions
758 * can_proto_register - register CAN transport protocol
759 * @cp: pointer to CAN protocol structure
763 * -EINVAL invalid (out of range) protocol number
764 * -EBUSY protocol already in use
765 * -ENOBUF if proto_register() fails
767 int can_proto_register(struct can_proto *cp)
769 int proto = cp->protocol;
772 if (proto < 0 || proto >= CAN_NPROTO) {
773 printk(KERN_ERR "can: protocol number %d out of range\n",
778 spin_lock(&proto_tab_lock);
779 if (proto_tab[proto]) {
780 printk(KERN_ERR "can: protocol %d already registered\n",
786 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
787 err = proto_register(cp->prot, 0);
792 proto_tab[proto] = cp;
794 /* use generic ioctl function if the module doesn't bring its own */
796 cp->ops->ioctl = can_ioctl;
799 spin_unlock(&proto_tab_lock);
803 EXPORT_SYMBOL(can_proto_register);
806 * can_proto_unregister - unregister CAN transport protocol
807 * @cp: pointer to CAN protocol structure
809 void can_proto_unregister(struct can_proto *cp)
811 int proto = cp->protocol;
813 spin_lock(&proto_tab_lock);
814 if (!proto_tab[proto]) {
815 printk(KERN_ERR "BUG: can: protocol %d is not registered\n",
818 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
819 proto_unregister(cp->prot);
821 proto_tab[proto] = NULL;
822 spin_unlock(&proto_tab_lock);
824 EXPORT_SYMBOL(can_proto_unregister);
827 * af_can notifier to create/remove CAN netdevice specific structs
829 static int can_notifier(struct notifier_block *nb, unsigned long msg,
832 struct net_device *dev = (struct net_device *)data;
833 struct dev_rcv_lists *d;
835 DBG("msg %ld for dev %p (%s idx %d)\n",
836 msg, dev, dev->name, dev->ifindex);
838 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
839 if (dev->nd_net != &init_net)
843 if (dev->type != ARPHRD_CAN)
848 case NETDEV_REGISTER:
851 * create new dev_rcv_lists for this device
853 * N.B. zeroing the struct is the correct initialization
854 * for the embedded hlist_head structs.
855 * Another list type, e.g. list_head, would require
856 * explicit initialization.
859 DBG("creating new dev_rcv_lists for %s\n", dev->name);
861 d = kzalloc(sizeof(*d), GFP_KERNEL);
864 "can: allocation of receive list failed\n");
869 spin_lock(&rcv_lists_lock);
870 hlist_add_head_rcu(&d->list, &rx_dev_list);
871 spin_unlock(&rcv_lists_lock);
875 case NETDEV_UNREGISTER:
876 spin_lock(&rcv_lists_lock);
878 d = find_dev_rcv_lists(dev);
880 DBG("remove dev_rcv_list for %s (%d entries)\n",
881 dev->name, d->entries);
884 d->remove_on_zero_entries = 1;
887 hlist_del_rcu(&d->list);
889 printk(KERN_ERR "can: notifier: receive list not "
890 "found for dev %s\n", dev->name);
892 spin_unlock(&rcv_lists_lock);
895 call_rcu(&d->rcu, can_rx_delete_device);
904 * af_can debugging stuff
907 #ifdef CONFIG_CAN_DEBUG_CORE
909 #define DBG_BSIZE 1024
912 * can_debug_cframe - print CAN frame
913 * @msg: pointer to message printed before the given CAN frame
914 * @cf: pointer to CAN frame
916 void can_debug_cframe(const char *msg, struct can_frame *cf, ...)
923 buf = kmalloc(DBG_BSIZE, GFP_ATOMIC);
927 len = sprintf(buf, KERN_DEBUG);
929 len += snprintf(buf + len, DBG_BSIZE - 64, msg, ap);
938 if (cf->can_id & CAN_EFF_FLAG)
939 len += sprintf(buf + len, "<%08X> [%X] ",
940 cf->can_id & CAN_EFF_MASK, dlc);
942 len += sprintf(buf + len, "<%03X> [%X] ",
943 cf->can_id & CAN_SFF_MASK, dlc);
945 for (i = 0; i < dlc; i++)
946 len += sprintf(buf + len, "%02X ", cf->data[i]);
948 if (cf->can_id & CAN_RTR_FLAG)
949 len += sprintf(buf + len, "(RTR)");
956 EXPORT_SYMBOL(can_debug_cframe);
959 * can_debug_skb - print socket buffer content to kernel log
960 * @skb: pointer to socket buffer
962 void can_debug_skb(struct sk_buff *skb)
967 buf = kmalloc(DBG_BSIZE, GFP_ATOMIC);
972 KERN_DEBUG " skbuff at %p, dev: %d, proto: %04x\n"
973 KERN_DEBUG " users: %d, dataref: %d, nr_frags: %d, "
974 "h,d,t,e,l: %p %+d %+d %+d, %d",
975 skb, skb->dev ? skb->dev->ifindex : -1,
976 ntohs(skb->protocol),
977 atomic_read(&skb->users),
978 atomic_read(&(skb_shinfo(skb)->dataref)),
979 skb_shinfo(skb)->nr_frags,
980 skb->head, skb->data - skb->head,
981 skb->tail - skb->head, skb->end - skb->head, skb->len);
982 nbytes = skb->end - skb->head;
983 for (i = 0; i < nbytes; i++) {
985 len += sprintf(buf + len, "\n" KERN_DEBUG " ");
986 if (len < DBG_BSIZE - 16) {
987 len += sprintf(buf + len, " %02x", skb->head[i]);
989 len += sprintf(buf + len, "...");
998 EXPORT_SYMBOL(can_debug_skb);
1003 * af_can module init/exit functions
1006 static struct packet_type can_packet __read_mostly = {
1007 .type = __constant_htons(ETH_P_CAN),
1012 static struct net_proto_family can_family_ops __read_mostly = {
1014 .create = can_create,
1015 .owner = THIS_MODULE,
1018 /* notifier block for netdevice event */
1019 static struct notifier_block can_netdev_notifier __read_mostly = {
1020 .notifier_call = can_notifier,
1023 static __init int can_init(void)
1027 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
1028 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
1031 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
1038 * Insert rx_alldev_list for reception on all devices.
1039 * This struct is zero initialized which is correct for the
1040 * embedded hlist heads, the dev pointer, and the entries counter.
1043 spin_lock(&rcv_lists_lock);
1044 hlist_add_head_rcu(&rx_alldev_list.list, &rx_dev_list);
1045 spin_unlock(&rcv_lists_lock);
1048 /* the statistics are updated every second (timer triggered) */
1049 init_timer(&stattimer);
1050 stattimer.function = can_stat_update;
1052 /* update every second */
1053 stattimer.expires = round_jiffies(jiffies + HZ);
1054 /* start statistics timer */
1055 add_timer(&stattimer);
1057 stattimer.function = NULL;
1062 /* protocol register */
1063 sock_register(&can_family_ops);
1064 register_netdevice_notifier(&can_netdev_notifier);
1065 dev_add_pack(&can_packet);
1070 static __exit void can_exit(void)
1072 struct dev_rcv_lists *d;
1073 struct hlist_node *n, *next;
1076 del_timer(&stattimer);
1081 /* protocol unregister */
1082 dev_remove_pack(&can_packet);
1083 unregister_netdevice_notifier(&can_netdev_notifier);
1084 sock_unregister(PF_CAN);
1086 /* remove rx_dev_list */
1087 spin_lock(&rcv_lists_lock);
1088 hlist_del(&rx_alldev_list.list);
1089 hlist_for_each_entry_safe(d, n, next, &rx_dev_list, list) {
1090 hlist_del(&d->list);
1093 spin_unlock(&rcv_lists_lock);
1095 kmem_cache_destroy(rcv_cache);
1098 module_init(can_init);
1099 module_exit(can_exit);