Btrfs: tweak the delayed inode reservations again
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / can / af_can.c
blob9b0c32a2690c3f168eb78b5193b80fa12c72f53f
1 /*
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
6 * All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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
39 * DAMAGE.
41 * Send feedback to <socketcan-users@lists.berlios.de>
45 #include <linux/module.h>
46 #include <linux/init.h>
47 #include <linux/kmod.h>
48 #include <linux/slab.h>
49 #include <linux/list.h>
50 #include <linux/spinlock.h>
51 #include <linux/rcupdate.h>
52 #include <linux/uaccess.h>
53 #include <linux/net.h>
54 #include <linux/netdevice.h>
55 #include <linux/socket.h>
56 #include <linux/if_ether.h>
57 #include <linux/if_arp.h>
58 #include <linux/skbuff.h>
59 #include <linux/can.h>
60 #include <linux/can/core.h>
61 #include <linux/ratelimit.h>
62 #include <net/net_namespace.h>
63 #include <net/sock.h>
65 #include "af_can.h"
67 static __initdata const char banner[] = KERN_INFO
68 "can: controller area network core (" CAN_VERSION_STRING ")\n";
70 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
71 MODULE_LICENSE("Dual BSD/GPL");
72 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
73 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
75 MODULE_ALIAS_NETPROTO(PF_CAN);
77 static int stats_timer __read_mostly = 1;
78 module_param(stats_timer, int, S_IRUGO);
79 MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
81 /* receive filters subscribed for 'all' CAN devices */
82 struct dev_rcv_lists can_rx_alldev_list;
83 static DEFINE_SPINLOCK(can_rcvlists_lock);
85 static struct kmem_cache *rcv_cache __read_mostly;
87 /* table of registered CAN protocols */
88 static const struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
89 static DEFINE_MUTEX(proto_tab_lock);
91 struct timer_list can_stattimer; /* timer for statistics update */
92 struct s_stats can_stats; /* packet statistics */
93 struct s_pstats can_pstats; /* receive list statistics */
96 * af_can socket functions
99 int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
101 struct sock *sk = sock->sk;
103 switch (cmd) {
105 case SIOCGSTAMP:
106 return sock_get_timestamp(sk, (struct timeval __user *)arg);
108 default:
109 return -ENOIOCTLCMD;
112 EXPORT_SYMBOL(can_ioctl);
114 static void can_sock_destruct(struct sock *sk)
116 skb_queue_purge(&sk->sk_receive_queue);
119 static const struct can_proto *can_get_proto(int protocol)
121 const struct can_proto *cp;
123 rcu_read_lock();
124 cp = rcu_dereference(proto_tab[protocol]);
125 if (cp && !try_module_get(cp->prot->owner))
126 cp = NULL;
127 rcu_read_unlock();
129 return cp;
132 static inline void can_put_proto(const struct can_proto *cp)
134 module_put(cp->prot->owner);
137 static int can_create(struct net *net, struct socket *sock, int protocol,
138 int kern)
140 struct sock *sk;
141 const struct can_proto *cp;
142 int err = 0;
144 sock->state = SS_UNCONNECTED;
146 if (protocol < 0 || protocol >= CAN_NPROTO)
147 return -EINVAL;
149 if (!net_eq(net, &init_net))
150 return -EAFNOSUPPORT;
152 cp = can_get_proto(protocol);
154 #ifdef CONFIG_MODULES
155 if (!cp) {
156 /* try to load protocol module if kernel is modular */
158 err = request_module("can-proto-%d", protocol);
161 * In case of error we only print a message but don't
162 * return the error code immediately. Below we will
163 * return -EPROTONOSUPPORT
165 if (err)
166 printk_ratelimited(KERN_ERR "can: request_module "
167 "(can-proto-%d) failed.\n", protocol);
169 cp = can_get_proto(protocol);
171 #endif
173 /* check for available protocol and correct usage */
175 if (!cp)
176 return -EPROTONOSUPPORT;
178 if (cp->type != sock->type) {
179 err = -EPROTOTYPE;
180 goto errout;
183 sock->ops = cp->ops;
185 sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
186 if (!sk) {
187 err = -ENOMEM;
188 goto errout;
191 sock_init_data(sock, sk);
192 sk->sk_destruct = can_sock_destruct;
194 if (sk->sk_prot->init)
195 err = sk->sk_prot->init(sk);
197 if (err) {
198 /* release sk on errors */
199 sock_orphan(sk);
200 sock_put(sk);
203 errout:
204 can_put_proto(cp);
205 return err;
209 * af_can tx path
213 * can_send - transmit a CAN frame (optional with local loopback)
214 * @skb: pointer to socket buffer with CAN frame in data section
215 * @loop: loopback for listeners on local CAN sockets (recommended default!)
217 * Due to the loopback this routine must not be called from hardirq context.
219 * Return:
220 * 0 on success
221 * -ENETDOWN when the selected interface is down
222 * -ENOBUFS on full driver queue (see net_xmit_errno())
223 * -ENOMEM when local loopback failed at calling skb_clone()
224 * -EPERM when trying to send on a non-CAN interface
225 * -EINVAL when the skb->data does not contain a valid CAN frame
227 int can_send(struct sk_buff *skb, int loop)
229 struct sk_buff *newskb = NULL;
230 struct can_frame *cf = (struct can_frame *)skb->data;
231 int err;
233 if (skb->len != sizeof(struct can_frame) || cf->can_dlc > 8) {
234 kfree_skb(skb);
235 return -EINVAL;
238 if (skb->dev->type != ARPHRD_CAN) {
239 kfree_skb(skb);
240 return -EPERM;
243 if (!(skb->dev->flags & IFF_UP)) {
244 kfree_skb(skb);
245 return -ENETDOWN;
248 skb->protocol = htons(ETH_P_CAN);
249 skb_reset_network_header(skb);
250 skb_reset_transport_header(skb);
252 if (loop) {
253 /* local loopback of sent CAN frames */
255 /* indication for the CAN driver: do loopback */
256 skb->pkt_type = PACKET_LOOPBACK;
259 * The reference to the originating sock may be required
260 * by the receiving socket to check whether the frame is
261 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
262 * Therefore we have to ensure that skb->sk remains the
263 * reference to the originating sock by restoring skb->sk
264 * after each skb_clone() or skb_orphan() usage.
267 if (!(skb->dev->flags & IFF_ECHO)) {
269 * If the interface is not capable to do loopback
270 * itself, we do it here.
272 newskb = skb_clone(skb, GFP_ATOMIC);
273 if (!newskb) {
274 kfree_skb(skb);
275 return -ENOMEM;
278 newskb->sk = skb->sk;
279 newskb->ip_summed = CHECKSUM_UNNECESSARY;
280 newskb->pkt_type = PACKET_BROADCAST;
282 } else {
283 /* indication for the CAN driver: no loopback required */
284 skb->pkt_type = PACKET_HOST;
287 /* send to netdevice */
288 err = dev_queue_xmit(skb);
289 if (err > 0)
290 err = net_xmit_errno(err);
292 if (err) {
293 kfree_skb(newskb);
294 return err;
297 if (newskb)
298 netif_rx_ni(newskb);
300 /* update statistics */
301 can_stats.tx_frames++;
302 can_stats.tx_frames_delta++;
304 return 0;
306 EXPORT_SYMBOL(can_send);
309 * af_can rx path
312 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
314 if (!dev)
315 return &can_rx_alldev_list;
316 else
317 return (struct dev_rcv_lists *)dev->ml_priv;
321 * find_rcv_list - determine optimal filterlist inside device filter struct
322 * @can_id: pointer to CAN identifier of a given can_filter
323 * @mask: pointer to CAN mask of a given can_filter
324 * @d: pointer to the device filter struct
326 * Description:
327 * Returns the optimal filterlist to reduce the filter handling in the
328 * receive path. This function is called by service functions that need
329 * to register or unregister a can_filter in the filter lists.
331 * A filter matches in general, when
333 * <received_can_id> & mask == can_id & mask
335 * so every bit set in the mask (even CAN_EFF_FLAG, CAN_RTR_FLAG) describe
336 * relevant bits for the filter.
338 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
339 * filter for error frames (CAN_ERR_FLAG bit set in mask). For error frames
340 * there is a special filterlist and a special rx path filter handling.
342 * Return:
343 * Pointer to optimal filterlist for the given can_id/mask pair.
344 * Constistency checked mask.
345 * Reduced can_id to have a preprocessed filter compare value.
347 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
348 struct dev_rcv_lists *d)
350 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
352 /* filter for error frames in extra filterlist */
353 if (*mask & CAN_ERR_FLAG) {
354 /* clear CAN_ERR_FLAG in filter entry */
355 *mask &= CAN_ERR_MASK;
356 return &d->rx[RX_ERR];
359 /* with cleared CAN_ERR_FLAG we have a simple mask/value filterpair */
361 #define CAN_EFF_RTR_FLAGS (CAN_EFF_FLAG | CAN_RTR_FLAG)
363 /* ensure valid values in can_mask for 'SFF only' frame filtering */
364 if ((*mask & CAN_EFF_FLAG) && !(*can_id & CAN_EFF_FLAG))
365 *mask &= (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS);
367 /* reduce condition testing at receive time */
368 *can_id &= *mask;
370 /* inverse can_id/can_mask filter */
371 if (inv)
372 return &d->rx[RX_INV];
374 /* mask == 0 => no condition testing at receive time */
375 if (!(*mask))
376 return &d->rx[RX_ALL];
378 /* extra filterlists for the subscription of a single non-RTR can_id */
379 if (((*mask & CAN_EFF_RTR_FLAGS) == CAN_EFF_RTR_FLAGS) &&
380 !(*can_id & CAN_RTR_FLAG)) {
382 if (*can_id & CAN_EFF_FLAG) {
383 if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) {
384 /* RFC: a future use-case for hash-tables? */
385 return &d->rx[RX_EFF];
387 } else {
388 if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS))
389 return &d->rx_sff[*can_id];
393 /* default: filter via can_id/can_mask */
394 return &d->rx[RX_FIL];
398 * can_rx_register - subscribe CAN frames from a specific interface
399 * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
400 * @can_id: CAN identifier (see description)
401 * @mask: CAN mask (see description)
402 * @func: callback function on filter match
403 * @data: returned parameter for callback function
404 * @ident: string for calling module indentification
406 * Description:
407 * Invokes the callback function with the received sk_buff and the given
408 * parameter 'data' on a matching receive filter. A filter matches, when
410 * <received_can_id> & mask == can_id & mask
412 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
413 * filter for error frames (CAN_ERR_FLAG bit set in mask).
415 * The provided pointer to the sk_buff is guaranteed to be valid as long as
416 * the callback function is running. The callback function must *not* free
417 * the given sk_buff while processing it's task. When the given sk_buff is
418 * needed after the end of the callback function it must be cloned inside
419 * the callback function with skb_clone().
421 * Return:
422 * 0 on success
423 * -ENOMEM on missing cache mem to create subscription entry
424 * -ENODEV unknown device
426 int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
427 void (*func)(struct sk_buff *, void *), void *data,
428 char *ident)
430 struct receiver *r;
431 struct hlist_head *rl;
432 struct dev_rcv_lists *d;
433 int err = 0;
435 /* insert new receiver (dev,canid,mask) -> (func,data) */
437 if (dev && dev->type != ARPHRD_CAN)
438 return -ENODEV;
440 r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
441 if (!r)
442 return -ENOMEM;
444 spin_lock(&can_rcvlists_lock);
446 d = find_dev_rcv_lists(dev);
447 if (d) {
448 rl = find_rcv_list(&can_id, &mask, d);
450 r->can_id = can_id;
451 r->mask = mask;
452 r->matches = 0;
453 r->func = func;
454 r->data = data;
455 r->ident = ident;
457 hlist_add_head_rcu(&r->list, rl);
458 d->entries++;
460 can_pstats.rcv_entries++;
461 if (can_pstats.rcv_entries_max < can_pstats.rcv_entries)
462 can_pstats.rcv_entries_max = can_pstats.rcv_entries;
463 } else {
464 kmem_cache_free(rcv_cache, r);
465 err = -ENODEV;
468 spin_unlock(&can_rcvlists_lock);
470 return err;
472 EXPORT_SYMBOL(can_rx_register);
475 * can_rx_delete_receiver - rcu callback for single receiver entry removal
477 static void can_rx_delete_receiver(struct rcu_head *rp)
479 struct receiver *r = container_of(rp, struct receiver, rcu);
481 kmem_cache_free(rcv_cache, r);
485 * can_rx_unregister - unsubscribe CAN frames from a specific interface
486 * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
487 * @can_id: CAN identifier
488 * @mask: CAN mask
489 * @func: callback function on filter match
490 * @data: returned parameter for callback function
492 * Description:
493 * Removes subscription entry depending on given (subscription) values.
495 void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
496 void (*func)(struct sk_buff *, void *), void *data)
498 struct receiver *r = NULL;
499 struct hlist_head *rl;
500 struct hlist_node *next;
501 struct dev_rcv_lists *d;
503 if (dev && dev->type != ARPHRD_CAN)
504 return;
506 spin_lock(&can_rcvlists_lock);
508 d = find_dev_rcv_lists(dev);
509 if (!d) {
510 printk(KERN_ERR "BUG: receive list not found for "
511 "dev %s, id %03X, mask %03X\n",
512 DNAME(dev), can_id, mask);
513 goto out;
516 rl = find_rcv_list(&can_id, &mask, d);
519 * Search the receiver list for the item to delete. This should
520 * exist, since no receiver may be unregistered that hasn't
521 * been registered before.
524 hlist_for_each_entry_rcu(r, next, rl, list) {
525 if (r->can_id == can_id && r->mask == mask &&
526 r->func == func && r->data == data)
527 break;
531 * Check for bugs in CAN protocol implementations:
532 * If no matching list item was found, the list cursor variable next
533 * will be NULL, while r will point to the last item of the list.
536 if (!next) {
537 printk(KERN_ERR "BUG: receive list entry not found for "
538 "dev %s, id %03X, mask %03X\n",
539 DNAME(dev), can_id, mask);
540 r = NULL;
541 goto out;
544 hlist_del_rcu(&r->list);
545 d->entries--;
547 if (can_pstats.rcv_entries > 0)
548 can_pstats.rcv_entries--;
550 /* remove device structure requested by NETDEV_UNREGISTER */
551 if (d->remove_on_zero_entries && !d->entries) {
552 kfree(d);
553 dev->ml_priv = NULL;
556 out:
557 spin_unlock(&can_rcvlists_lock);
559 /* schedule the receiver item for deletion */
560 if (r)
561 call_rcu(&r->rcu, can_rx_delete_receiver);
563 EXPORT_SYMBOL(can_rx_unregister);
565 static inline void deliver(struct sk_buff *skb, struct receiver *r)
567 r->func(skb, r->data);
568 r->matches++;
571 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
573 struct receiver *r;
574 struct hlist_node *n;
575 int matches = 0;
576 struct can_frame *cf = (struct can_frame *)skb->data;
577 canid_t can_id = cf->can_id;
579 if (d->entries == 0)
580 return 0;
582 if (can_id & CAN_ERR_FLAG) {
583 /* check for error frame entries only */
584 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ERR], list) {
585 if (can_id & r->mask) {
586 deliver(skb, r);
587 matches++;
590 return matches;
593 /* check for unfiltered entries */
594 hlist_for_each_entry_rcu(r, n, &d->rx[RX_ALL], list) {
595 deliver(skb, r);
596 matches++;
599 /* check for can_id/mask entries */
600 hlist_for_each_entry_rcu(r, n, &d->rx[RX_FIL], list) {
601 if ((can_id & r->mask) == r->can_id) {
602 deliver(skb, r);
603 matches++;
607 /* check for inverted can_id/mask entries */
608 hlist_for_each_entry_rcu(r, n, &d->rx[RX_INV], list) {
609 if ((can_id & r->mask) != r->can_id) {
610 deliver(skb, r);
611 matches++;
615 /* check filterlists for single non-RTR can_ids */
616 if (can_id & CAN_RTR_FLAG)
617 return matches;
619 if (can_id & CAN_EFF_FLAG) {
620 hlist_for_each_entry_rcu(r, n, &d->rx[RX_EFF], list) {
621 if (r->can_id == can_id) {
622 deliver(skb, r);
623 matches++;
626 } else {
627 can_id &= CAN_SFF_MASK;
628 hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
629 deliver(skb, r);
630 matches++;
634 return matches;
637 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
638 struct packet_type *pt, struct net_device *orig_dev)
640 struct dev_rcv_lists *d;
641 struct can_frame *cf = (struct can_frame *)skb->data;
642 int matches;
644 if (!net_eq(dev_net(dev), &init_net))
645 goto drop;
647 if (WARN_ONCE(dev->type != ARPHRD_CAN ||
648 skb->len != sizeof(struct can_frame) ||
649 cf->can_dlc > 8,
650 "PF_CAN: dropped non conform skbuf: "
651 "dev type %d, len %d, can_dlc %d\n",
652 dev->type, skb->len, cf->can_dlc))
653 goto drop;
655 /* update statistics */
656 can_stats.rx_frames++;
657 can_stats.rx_frames_delta++;
659 rcu_read_lock();
661 /* deliver the packet to sockets listening on all devices */
662 matches = can_rcv_filter(&can_rx_alldev_list, skb);
664 /* find receive list for this device */
665 d = find_dev_rcv_lists(dev);
666 if (d)
667 matches += can_rcv_filter(d, skb);
669 rcu_read_unlock();
671 /* consume the skbuff allocated by the netdevice driver */
672 consume_skb(skb);
674 if (matches > 0) {
675 can_stats.matches++;
676 can_stats.matches_delta++;
679 return NET_RX_SUCCESS;
681 drop:
682 kfree_skb(skb);
683 return NET_RX_DROP;
687 * af_can protocol functions
691 * can_proto_register - register CAN transport protocol
692 * @cp: pointer to CAN protocol structure
694 * Return:
695 * 0 on success
696 * -EINVAL invalid (out of range) protocol number
697 * -EBUSY protocol already in use
698 * -ENOBUF if proto_register() fails
700 int can_proto_register(const struct can_proto *cp)
702 int proto = cp->protocol;
703 int err = 0;
705 if (proto < 0 || proto >= CAN_NPROTO) {
706 printk(KERN_ERR "can: protocol number %d out of range\n",
707 proto);
708 return -EINVAL;
711 err = proto_register(cp->prot, 0);
712 if (err < 0)
713 return err;
715 mutex_lock(&proto_tab_lock);
717 if (proto_tab[proto]) {
718 printk(KERN_ERR "can: protocol %d already registered\n",
719 proto);
720 err = -EBUSY;
721 } else
722 rcu_assign_pointer(proto_tab[proto], cp);
724 mutex_unlock(&proto_tab_lock);
726 if (err < 0)
727 proto_unregister(cp->prot);
729 return err;
731 EXPORT_SYMBOL(can_proto_register);
734 * can_proto_unregister - unregister CAN transport protocol
735 * @cp: pointer to CAN protocol structure
737 void can_proto_unregister(const struct can_proto *cp)
739 int proto = cp->protocol;
741 mutex_lock(&proto_tab_lock);
742 BUG_ON(proto_tab[proto] != cp);
743 rcu_assign_pointer(proto_tab[proto], NULL);
744 mutex_unlock(&proto_tab_lock);
746 synchronize_rcu();
748 proto_unregister(cp->prot);
750 EXPORT_SYMBOL(can_proto_unregister);
753 * af_can notifier to create/remove CAN netdevice specific structs
755 static int can_notifier(struct notifier_block *nb, unsigned long msg,
756 void *data)
758 struct net_device *dev = (struct net_device *)data;
759 struct dev_rcv_lists *d;
761 if (!net_eq(dev_net(dev), &init_net))
762 return NOTIFY_DONE;
764 if (dev->type != ARPHRD_CAN)
765 return NOTIFY_DONE;
767 switch (msg) {
769 case NETDEV_REGISTER:
771 /* create new dev_rcv_lists for this device */
772 d = kzalloc(sizeof(*d), GFP_KERNEL);
773 if (!d) {
774 printk(KERN_ERR
775 "can: allocation of receive list failed\n");
776 return NOTIFY_DONE;
778 BUG_ON(dev->ml_priv);
779 dev->ml_priv = d;
781 break;
783 case NETDEV_UNREGISTER:
784 spin_lock(&can_rcvlists_lock);
786 d = dev->ml_priv;
787 if (d) {
788 if (d->entries)
789 d->remove_on_zero_entries = 1;
790 else {
791 kfree(d);
792 dev->ml_priv = NULL;
794 } else
795 printk(KERN_ERR "can: notifier: receive list not "
796 "found for dev %s\n", dev->name);
798 spin_unlock(&can_rcvlists_lock);
800 break;
803 return NOTIFY_DONE;
807 * af_can module init/exit functions
810 static struct packet_type can_packet __read_mostly = {
811 .type = cpu_to_be16(ETH_P_CAN),
812 .dev = NULL,
813 .func = can_rcv,
816 static const struct net_proto_family can_family_ops = {
817 .family = PF_CAN,
818 .create = can_create,
819 .owner = THIS_MODULE,
822 /* notifier block for netdevice event */
823 static struct notifier_block can_netdev_notifier __read_mostly = {
824 .notifier_call = can_notifier,
827 static __init int can_init(void)
829 printk(banner);
831 memset(&can_rx_alldev_list, 0, sizeof(can_rx_alldev_list));
833 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
834 0, 0, NULL);
835 if (!rcv_cache)
836 return -ENOMEM;
838 if (stats_timer) {
839 /* the statistics are updated every second (timer triggered) */
840 setup_timer(&can_stattimer, can_stat_update, 0);
841 mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
842 } else
843 can_stattimer.function = NULL;
845 can_init_proc();
847 /* protocol register */
848 sock_register(&can_family_ops);
849 register_netdevice_notifier(&can_netdev_notifier);
850 dev_add_pack(&can_packet);
852 return 0;
855 static __exit void can_exit(void)
857 struct net_device *dev;
859 if (stats_timer)
860 del_timer_sync(&can_stattimer);
862 can_remove_proc();
864 /* protocol unregister */
865 dev_remove_pack(&can_packet);
866 unregister_netdevice_notifier(&can_netdev_notifier);
867 sock_unregister(PF_CAN);
869 /* remove created dev_rcv_lists from still registered CAN devices */
870 rcu_read_lock();
871 for_each_netdev_rcu(&init_net, dev) {
872 if (dev->type == ARPHRD_CAN && dev->ml_priv){
874 struct dev_rcv_lists *d = dev->ml_priv;
876 BUG_ON(d->entries);
877 kfree(d);
878 dev->ml_priv = NULL;
881 rcu_read_unlock();
883 rcu_barrier(); /* Wait for completion of call_rcu()'s */
885 kmem_cache_destroy(rcv_cache);
888 module_init(can_init);
889 module_exit(can_exit);