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>
73 #include <linux/can/version.h> /* for RCSID. Removed by mkpatch script */
76 static __initdata const char banner[] = KERN_INFO
77 "can: controller area network core (" CAN_VERSION_STRING ")\n";
79 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
80 MODULE_LICENSE("Dual BSD/GPL");
81 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
82 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
84 MODULE_ALIAS_NETPROTO(PF_CAN);
86 static int stats_timer __read_mostly = 1;
87 module_param(stats_timer, int, S_IRUGO);
88 MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
90 #ifdef CONFIG_CAN_DEBUG_CORE
91 #define DBG_PREFIX "can"
92 #define DBG_VAR can_debug
93 static int can_debug __read_mostly;
94 module_param_named(debug, can_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);
153 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
155 kfree(sk->sk_protinfo);
159 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
160 static int can_create(struct net *net, struct socket *sock, int protocol)
162 static int can_create(struct socket *sock, int protocol)
166 struct can_proto *cp;
167 char module_name[sizeof("can-proto-000")];
170 DBG("socket %p, type %d, proto %d\n", sock, sock->type, protocol);
172 sock->state = SS_UNCONNECTED;
174 if (protocol < 0 || protocol >= CAN_NPROTO)
177 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
178 if (net != &init_net)
179 return -EAFNOSUPPORT;
182 DBG("looking up proto %d in proto_tab[]\n", protocol);
184 /* try to load protocol module, when CONFIG_KMOD is defined */
185 if (!proto_tab[protocol]) {
186 sprintf(module_name, "can-proto-%d", protocol);
187 err = request_module(module_name);
190 * In case of error we only print a message but don't
191 * return the error code immediately. Below we will
192 * return -EPROTONOSUPPORT
194 if (err == -ENOSYS) {
195 if (printk_ratelimit())
196 printk(KERN_INFO "can: request_module(%s)"
197 " not implemented.\n", module_name);
199 if (printk_ratelimit())
200 printk(KERN_ERR "can: request_module(%s)"
201 " failed.\n", module_name);
205 spin_lock(&proto_tab_lock);
206 cp = proto_tab[protocol];
207 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
208 if (cp && !try_module_get(cp->prot->owner))
211 if (cp && !try_module_get(cp->owner))
214 spin_unlock(&proto_tab_lock);
216 /* check for available protocol and correct usage */
219 return -EPROTONOSUPPORT;
221 if (cp->type != sock->type) {
222 err = -EPROTONOSUPPORT;
226 if (cp->capability >= 0 && !capable(cp->capability)) {
233 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
234 sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
235 #elif LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
236 sk = sk_alloc(PF_CAN, GFP_KERNEL, cp->prot, 1);
238 sk = sk_alloc(PF_CAN, GFP_KERNEL, 1, 0);
245 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,12)
247 sk->sk_protinfo = kmalloc(cp->obj_size, GFP_KERNEL);
248 if (!sk->sk_protinfo) {
254 sk_set_owner(sk, proto_tab[protocol]->owner);
257 sock_init_data(sock, sk);
258 sk->sk_destruct = can_sock_destruct;
260 DBG("created sock: %p\n", sk);
262 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
263 if (sk->sk_prot->init)
264 err = sk->sk_prot->init(sk);
271 /* release sk on errors */
277 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
278 module_put(cp->prot->owner);
280 module_put(cp->owner);
290 * can_send - transmit a CAN frame (optional with local loopback)
291 * @skb: pointer to socket buffer with CAN frame in data section
292 * @loop: loopback for listeners on local CAN sockets (recommended default!)
296 * -ENETDOWN when the selected interface is down
297 * -ENOBUFS on full driver queue (see net_xmit_errno())
298 * -ENOMEM when local loopback failed at calling skb_clone()
299 * -EPERM when trying to send on a non-CAN interface
301 int can_send(struct sk_buff *skb, int loop)
305 if (skb->dev->type != ARPHRD_CAN) {
310 if (!(skb->dev->flags & IFF_UP)) {
315 skb->protocol = htons(ETH_P_CAN);
316 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
317 skb_reset_network_header(skb);
318 skb_reset_transport_header(skb);
320 skb->nh.raw = skb->data;
321 skb->h.raw = skb->data;
325 /* local loopback of sent CAN frames */
327 /* indication for the CAN driver: do loopback */
328 skb->pkt_type = PACKET_LOOPBACK;
331 * The reference to the originating sock may be required
332 * by the receiving socket to check whether the frame is
333 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
334 * Therefore we have to ensure that skb->sk remains the
335 * reference to the originating sock by restoring skb->sk
336 * after each skb_clone() or skb_orphan() usage.
339 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,25)
340 #define IFF_ECHO IFF_LOOPBACK
342 if (!(skb->dev->flags & IFF_ECHO)) {
344 * If the interface is not capable to do loopback
345 * itself, we do it here.
347 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
354 newskb->sk = skb->sk;
355 newskb->ip_summed = CHECKSUM_UNNECESSARY;
356 newskb->pkt_type = PACKET_BROADCAST;
360 /* indication for the CAN driver: no loopback required */
361 skb->pkt_type = PACKET_HOST;
364 /* send to netdevice */
365 err = dev_queue_xmit(skb);
367 err = net_xmit_errno(err);
369 /* update statistics */
371 stats.tx_frames_delta++;
375 EXPORT_SYMBOL(can_send);
381 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
383 struct dev_rcv_lists *d = NULL;
384 struct hlist_node *n;
387 * find receive list for this device
389 * The hlist_for_each_entry*() macros curse through the list
390 * using the pointer variable n and set d to the containing
391 * struct in each list iteration. Therefore, after list
392 * iteration, d is unmodified when the list is empty, and it
393 * points to last list element, when the list is non-empty
394 * but no match in the loop body is found. I.e. d is *not*
395 * NULL when no match is found. We can, however, use the
396 * cursor variable n to decide if a match was found.
399 hlist_for_each_entry_rcu(d, n, &rx_dev_list, list) {
407 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
408 struct dev_rcv_lists *d)
410 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
412 /* filter error frames */
413 if (*mask & CAN_ERR_FLAG) {
414 /* clear CAN_ERR_FLAG in list entry */
415 *mask &= CAN_ERR_MASK;
416 return &d->rx[RX_ERR];
419 /* ensure valid values in can_mask */
420 if (*mask & CAN_EFF_FLAG)
421 *mask &= (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG);
423 *mask &= (CAN_SFF_MASK | CAN_RTR_FLAG);
425 /* reduce condition testing at receive time */
428 /* inverse can_id/can_mask filter */
430 return &d->rx[RX_INV];
432 /* mask == 0 => no condition testing at receive time */
434 return &d->rx[RX_ALL];
436 /* use extra filterset for the subscription of exactly *ONE* can_id */
437 if (*can_id & CAN_EFF_FLAG) {
438 if (*mask == (CAN_EFF_MASK | CAN_EFF_FLAG)) {
439 /* RFC: a use-case for hash-tables in the future? */
440 return &d->rx[RX_EFF];
443 if (*mask == CAN_SFF_MASK)
444 return &d->rx_sff[*can_id];
447 /* default: filter via can_id/can_mask */
448 return &d->rx[RX_FIL];
452 * can_rx_register - subscribe CAN frames from a specific interface
453 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
454 * @can_id: CAN identifier (see description)
455 * @mask: CAN mask (see description)
456 * @func: callback function on filter match
457 * @data: returned parameter for callback function
458 * @ident: string for calling module indentification
461 * Invokes the callback function with the received sk_buff and the given
462 * parameter 'data' on a matching receive filter. A filter matches, when
464 * <received_can_id> & mask == can_id & mask
466 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
467 * filter for error frames (CAN_ERR_FLAG bit set in mask).
471 * -ENOMEM on missing cache mem to create subscription entry
472 * -ENODEV unknown device
474 int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
475 void (*func)(struct sk_buff *, void *), void *data,
479 struct hlist_head *rl;
480 struct dev_rcv_lists *d;
483 /* insert new receiver (dev,canid,mask) -> (func,data) */
485 DBG("dev %p (%s), id %03X, mask %03X, callback %p, data %p, "
486 "ident %s\n", dev, DNAME(dev), can_id, mask, func, data, ident);
488 r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
492 spin_lock(&rcv_lists_lock);
494 d = find_dev_rcv_lists(dev);
496 rl = find_rcv_list(&can_id, &mask, d);
505 hlist_add_head_rcu(&r->list, rl);
508 pstats.rcv_entries++;
509 if (pstats.rcv_entries_max < pstats.rcv_entries)
510 pstats.rcv_entries_max = pstats.rcv_entries;
512 DBG("receive list not found for dev %s, id %03X, mask %03X\n",
513 DNAME(dev), can_id, mask);
514 kmem_cache_free(rcv_cache, r);
518 spin_unlock(&rcv_lists_lock);
522 EXPORT_SYMBOL(can_rx_register);
525 * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
527 static void can_rx_delete_device(struct rcu_head *rp)
529 struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
531 DBG("removing dev_rcv_list at %p\n", d);
536 * can_rx_delete_receiver - rcu callback for single receiver entry removal
538 static void can_rx_delete_receiver(struct rcu_head *rp)
540 struct receiver *r = container_of(rp, struct receiver, rcu);
542 DBG("removing receiver at %p\n", r);
543 kmem_cache_free(rcv_cache, r);
547 * can_rx_unregister - unsubscribe CAN frames from a specific interface
548 * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
549 * @can_id: CAN identifier
551 * @func: callback function on filter match
552 * @data: returned parameter for callback function
555 * Removes subscription entry depending on given (subscription) values.
557 void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
558 void (*func)(struct sk_buff *, void *), void *data)
560 struct receiver *r = NULL;
561 struct hlist_head *rl;
562 struct hlist_node *next;
563 struct dev_rcv_lists *d;
565 DBG("dev %p (%s), id %03X, mask %03X, callback %p, data %p\n",
566 dev, DNAME(dev), can_id, mask, func, data);
568 spin_lock(&rcv_lists_lock);
570 d = find_dev_rcv_lists(dev);
572 printk(KERN_ERR "BUG: receive list not found for "
573 "dev %s, id %03X, mask %03X\n",
574 DNAME(dev), can_id, mask);
578 rl = find_rcv_list(&can_id, &mask, d);
581 * Search the receiver list for the item to delete. This should
582 * exist, since no receiver may be unregistered that hasn't
583 * been registered before.
586 hlist_for_each_entry_rcu(r, next, rl, list) {
587 if (r->can_id == can_id && r->mask == mask
588 && r->func == func && r->data == data)
593 * Check for bugs in CAN protocol implementations:
594 * If no matching list item was found, the list cursor variable next
595 * will be NULL, while r will point to the last item of the list.
599 printk(KERN_ERR "BUG: receive list entry not found for "
600 "dev %s, id %03X, mask %03X\n",
601 DNAME(dev), can_id, mask);
607 hlist_del_rcu(&r->list);
610 if (pstats.rcv_entries > 0)
611 pstats.rcv_entries--;
613 /* remove device structure requested by NETDEV_UNREGISTER */
614 if (d->remove_on_zero_entries && !d->entries) {
615 DBG("removing dev_rcv_list for %s on zero entries\n",
617 hlist_del_rcu(&d->list);
622 spin_unlock(&rcv_lists_lock);
624 /* schedule the receiver item for deletion */
626 call_rcu(&r->rcu, can_rx_delete_receiver);
628 /* schedule the device structure for deletion */
630 call_rcu(&d->rcu, can_rx_delete_device);
632 EXPORT_SYMBOL(can_rx_unregister);
634 static inline void deliver(struct sk_buff *skb, struct receiver *r)
636 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
638 DBG("skbuff %p cloned to %p\n", skb, clone);
641 r->func(clone, r->data);
646 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
649 struct hlist_node *n;
651 struct can_frame *cf = (struct can_frame *)skb->data;
652 canid_t can_id = cf->can_id;
657 if (can_id & CAN_ERR_FLAG) {
658 /* check for error frame entries only */
659 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ERR], list) {
660 if (can_id & r->mask) {
661 DBG("match on rx_err skbuff %p\n", skb);
669 /* check for unfiltered entries */
670 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ALL], list) {
671 DBG("match on rx_all skbuff %p\n", skb);
676 /* check for can_id/mask entries */
677 hlist_for_each_entry_rcu(r, n, &d->rx[RX_FIL], list) {
678 if ((can_id & r->mask) == r->can_id) {
679 DBG("match on rx_fil skbuff %p\n", skb);
685 /* check for inverted can_id/mask entries */
686 hlist_for_each_entry_rcu(r, n, &d->rx[RX_INV], list) {
687 if ((can_id & r->mask) != r->can_id) {
688 DBG("match on rx_inv skbuff %p\n", skb);
694 /* check CAN_ID specific entries */
695 if (can_id & CAN_EFF_FLAG) {
696 hlist_for_each_entry_rcu(r, n, &d->rx[RX_EFF], list) {
697 if (r->can_id == can_id) {
698 DBG("match on rx_eff skbuff %p\n", skb);
704 can_id &= CAN_SFF_MASK;
705 hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
706 DBG("match on rx_sff skbuff %p\n", skb);
715 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
716 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
717 struct packet_type *pt, struct net_device *orig_dev)
719 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
720 struct packet_type *pt)
723 struct dev_rcv_lists *d;
726 DBG("received skbuff on device %s, ptype %04x\n",
727 dev->name, ntohs(pt->type));
729 DBG_FRAME("can: can_rcv: received CAN frame",
730 (struct can_frame *)skb->data);
732 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
733 if (dev->type != ARPHRD_CAN || dev->nd_net != &init_net) {
735 if (dev->type != ARPHRD_CAN) {
741 /* update statistics */
743 stats.rx_frames_delta++;
747 /* deliver the packet to sockets listening on all devices */
748 matches = can_rcv_filter(&rx_alldev_list, skb);
750 /* find receive list for this device */
751 d = find_dev_rcv_lists(dev);
753 matches += can_rcv_filter(d, skb);
757 /* free the skbuff allocated by the netdevice driver */
758 DBG("freeing skbuff %p\n", skb);
763 stats.matches_delta++;
770 * af_can protocol functions
774 * can_proto_register - register CAN transport protocol
775 * @cp: pointer to CAN protocol structure
779 * -EINVAL invalid (out of range) protocol number
780 * -EBUSY protocol already in use
781 * -ENOBUF if proto_register() fails
783 int can_proto_register(struct can_proto *cp)
785 int proto = cp->protocol;
788 if (proto < 0 || proto >= CAN_NPROTO) {
789 printk(KERN_ERR "can: protocol number %d out of range\n",
794 spin_lock(&proto_tab_lock);
795 if (proto_tab[proto]) {
796 printk(KERN_ERR "can: protocol %d already registered\n",
802 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
803 err = proto_register(cp->prot, 0);
808 proto_tab[proto] = cp;
810 /* use generic ioctl function if the module doesn't bring its own */
812 cp->ops->ioctl = can_ioctl;
815 spin_unlock(&proto_tab_lock);
819 EXPORT_SYMBOL(can_proto_register);
822 * can_proto_unregister - unregister CAN transport protocol
823 * @cp: pointer to CAN protocol structure
825 void can_proto_unregister(struct can_proto *cp)
827 int proto = cp->protocol;
829 spin_lock(&proto_tab_lock);
830 if (!proto_tab[proto]) {
831 printk(KERN_ERR "BUG: can: protocol %d is not registered\n",
834 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,12)
835 proto_unregister(cp->prot);
837 proto_tab[proto] = NULL;
838 spin_unlock(&proto_tab_lock);
840 EXPORT_SYMBOL(can_proto_unregister);
843 * af_can notifier to create/remove CAN netdevice specific structs
845 static int can_notifier(struct notifier_block *nb, unsigned long msg,
848 struct net_device *dev = (struct net_device *)data;
849 struct dev_rcv_lists *d;
851 DBG("msg %ld for dev %p (%s idx %d)\n",
852 msg, dev, dev->name, dev->ifindex);
854 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,24)
855 if (dev->nd_net != &init_net)
859 if (dev->type != ARPHRD_CAN)
864 case NETDEV_REGISTER:
867 * create new dev_rcv_lists for this device
869 * N.B. zeroing the struct is the correct initialization
870 * for the embedded hlist_head structs.
871 * Another list type, e.g. list_head, would require
872 * explicit initialization.
875 DBG("creating new dev_rcv_lists for %s\n", dev->name);
877 d = kzalloc(sizeof(*d), GFP_KERNEL);
880 "can: allocation of receive list failed\n");
885 spin_lock(&rcv_lists_lock);
886 hlist_add_head_rcu(&d->list, &rx_dev_list);
887 spin_unlock(&rcv_lists_lock);
891 case NETDEV_UNREGISTER:
892 spin_lock(&rcv_lists_lock);
894 d = find_dev_rcv_lists(dev);
896 DBG("remove dev_rcv_list for %s (%d entries)\n",
897 dev->name, d->entries);
900 d->remove_on_zero_entries = 1;
903 hlist_del_rcu(&d->list);
905 printk(KERN_ERR "can: notifier: receive list not "
906 "found for dev %s\n", dev->name);
908 spin_unlock(&rcv_lists_lock);
911 call_rcu(&d->rcu, can_rx_delete_device);
920 * af_can debugging stuff
923 #ifdef CONFIG_CAN_DEBUG_CORE
926 * can_debug_cframe - print CAN frame
927 * @msg: pointer to message printed before the given CAN frame
928 * @cf: pointer to CAN frame
930 void can_debug_cframe(const char *msg, struct can_frame *cf)
940 if (cf->can_id & CAN_EFF_FLAG)
941 sprintf(idbuf, "<%08X>", cf->can_id & CAN_EFF_MASK);
943 sprintf(idbuf, "<%03X>", cf->can_id & CAN_SFF_MASK);
945 if (cf->can_id & CAN_RTR_FLAG)
946 sprintf(hexbuf, "(RTR)");
948 hex_dump_to_buffer(cf->data, dlc, 16, 1, hexbuf, 28, 0);
950 printk(KERN_DEBUG "%s: %s [%d] %s\n", msg, idbuf, dlc, hexbuf);
952 EXPORT_SYMBOL(can_debug_cframe);
955 * can_debug_skb - print socket buffer content to kernel log
956 * @skb: pointer to socket buffer
958 void can_debug_skb(struct sk_buff *skb)
960 printk(KERN_DEBUG " skbuff at %p, dev: %d, proto: %04x\n"
961 KERN_DEBUG " users: %d, dataref: %d, nr_frags: %d, "
962 "h,d,t,e,l: %p %+d %+d %+d, %d\n",
963 skb, skb->dev ? skb->dev->ifindex : -1,
964 ntohs(skb->protocol),
965 atomic_read(&skb->users),
966 atomic_read(&(skb_shinfo(skb)->dataref)),
967 skb_shinfo(skb)->nr_frags,
968 skb->head, skb->data - skb->head,
969 skb->tail - skb->head, skb->end - skb->head, skb->len);
971 print_hex_dump(KERN_DEBUG, "skb_head: ", DUMP_PREFIX_NONE,
972 16, 1, skb->head, skb->end - skb->head, 0);
974 EXPORT_SYMBOL(can_debug_skb);
979 * af_can module init/exit functions
982 static struct packet_type can_packet __read_mostly = {
983 .type = __constant_htons(ETH_P_CAN),
988 static struct net_proto_family can_family_ops __read_mostly = {
990 .create = can_create,
991 .owner = THIS_MODULE,
994 /* notifier block for netdevice event */
995 static struct notifier_block can_netdev_notifier __read_mostly = {
996 .notifier_call = can_notifier,
999 static __init int can_init(void)
1003 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23)
1004 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
1007 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
1014 * Insert rx_alldev_list for reception on all devices.
1015 * This struct is zero initialized which is correct for the
1016 * embedded hlist heads, the dev pointer, and the entries counter.
1019 spin_lock(&rcv_lists_lock);
1020 hlist_add_head_rcu(&rx_alldev_list.list, &rx_dev_list);
1021 spin_unlock(&rcv_lists_lock);
1024 /* the statistics are updated every second (timer triggered) */
1025 init_timer(&stattimer);
1026 stattimer.function = can_stat_update;
1028 /* update every second */
1029 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20)
1030 stattimer.expires = round_jiffies(jiffies + HZ);
1032 stattimer.expires = jiffies + HZ;
1034 /* start statistics timer */
1035 add_timer(&stattimer);
1037 stattimer.function = NULL;
1041 /* protocol register */
1042 sock_register(&can_family_ops);
1043 register_netdevice_notifier(&can_netdev_notifier);
1044 dev_add_pack(&can_packet);
1049 static __exit void can_exit(void)
1051 struct dev_rcv_lists *d;
1052 struct hlist_node *n, *next;
1055 del_timer(&stattimer);
1059 /* protocol unregister */
1060 dev_remove_pack(&can_packet);
1061 unregister_netdevice_notifier(&can_netdev_notifier);
1062 sock_unregister(PF_CAN);
1064 /* remove rx_dev_list */
1065 spin_lock(&rcv_lists_lock);
1066 hlist_del(&rx_alldev_list.list);
1067 hlist_for_each_entry_safe(d, n, next, &rx_dev_list, list) {
1068 hlist_del(&d->list);
1071 spin_unlock(&rcv_lists_lock);
1073 kmem_cache_destroy(rcv_cache);
1076 module_init(can_init);
1077 module_exit(can_exit);