1 files changed, 861 insertions, 0 deletions

diff --git a/net/can/af_can.c b/net/can/af_can.c
new file mode 100644
index 000000000000..5158e886630f
--- /dev/null
+++ b/net/can/af_can.c
@@ -0,0 +1,861 @@
+/*
+ * af_can.c - Protocol family CAN core module
+ *            (used by different CAN protocol modules)
+ *
+ * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Volkswagen nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * Alternatively, provided that this notice is retained in full, this
+ * software may be distributed under the terms of the GNU General
+ * Public License ("GPL") version 2, in which case the provisions of the
+ * GPL apply INSTEAD OF those given above.
+ *
+ * The provided data structures and external interfaces from this code
+ * are not restricted to be used by modules with a GPL compatible license.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Send feedback to <socketcan-users@lists.berlios.de>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kmod.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/rcupdate.h>
+#include <linux/uaccess.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/if_ether.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <linux/can.h>
+#include <linux/can/core.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+
+#include "af_can.h"
+
+static __initdata const char banner[] = KERN_INFO
+        "can: controller area network core (" CAN_VERSION_STRING ")\n";
+
+MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
+              "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
+
+MODULE_ALIAS_NETPROTO(PF_CAN);
+
+static int stats_timer __read_mostly = 1;
+module_param(stats_timer, int, S_IRUGO);
+MODULE_PARM_DESC(stats_timer, "enable timer for statistics (default:on)");
+
+HLIST_HEAD(can_rx_dev_list);
+static struct dev_rcv_lists can_rx_alldev_list;
+static DEFINE_SPINLOCK(can_rcvlists_lock);
+
+static struct kmem_cache *rcv_cache __read_mostly;
+
+/* table of registered CAN protocols */
+static struct can_proto *proto_tab[CAN_NPROTO] __read_mostly;
+static DEFINE_SPINLOCK(proto_tab_lock);
+
+struct timer_list can_stattimer;   /* timer for statistics update */
+struct s_stats    can_stats;       /* packet statistics */
+struct s_pstats   can_pstats;      /* receive list statistics */
+
+/*
+ * af_can socket functions
+ */
+
+static int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+        struct sock *sk = sock->sk;
+
+        switch (cmd) {
+
+        case SIOCGSTAMP:
+                return sock_get_timestamp(sk, (struct timeval __user *)arg);
+
+        default:
+                return -ENOIOCTLCMD;
+        }
+}
+
+static void can_sock_destruct(struct sock *sk)
+{
+        skb_queue_purge(&sk->sk_receive_queue);
+}
+
+static int can_create(struct net *net, struct socket *sock, int protocol)
+{
+        struct sock *sk;
+        struct can_proto *cp;
+        char module_name[sizeof("can-proto-000")];
+        int err = 0;
+
+        sock->state = SS_UNCONNECTED;
+
+        if (protocol < 0 || protocol >= CAN_NPROTO)
+                return -EINVAL;
+
+        if (net != &init_net)
+                return -EAFNOSUPPORT;
+
+        /* try to load protocol module, when CONFIG_KMOD is defined */
+        if (!proto_tab[protocol]) {
+                sprintf(module_name, "can-proto-%d", protocol);
+                err = request_module(module_name);
+
+                /*
+                 * In case of error we only print a message but don't
+                 * return the error code immediately.  Below we will
+                 * return -EPROTONOSUPPORT
+                 */
+                if (err == -ENOSYS) {
+                        if (printk_ratelimit())
+                                printk(KERN_INFO "can: request_module(%s)"
+                                       " not implemented.\n", module_name);
+                } else if (err) {
+                        if (printk_ratelimit())
+                                printk(KERN_ERR "can: request_module(%s)"
+                                       " failed.\n", module_name);
+                }
+        }
+
+        spin_lock(&proto_tab_lock);
+        cp = proto_tab[protocol];
+        if (cp && !try_module_get(cp->prot->owner))
+                cp = NULL;
+        spin_unlock(&proto_tab_lock);
+
+        /* check for available protocol and correct usage */
+
+        if (!cp)
+                return -EPROTONOSUPPORT;
+
+        if (cp->type != sock->type) {
+                err = -EPROTONOSUPPORT;
+                goto errout;
+        }
+
+        if (cp->capability >= 0 && !capable(cp->capability)) {
+                err = -EPERM;
+                goto errout;
+        }
+
+        sock->ops = cp->ops;
+
+        sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
+        if (!sk) {
+                err = -ENOMEM;
+                goto errout;
+        }
+
+        sock_init_data(sock, sk);
+        sk->sk_destruct = can_sock_destruct;
+
+        if (sk->sk_prot->init)
+                err = sk->sk_prot->init(sk);
+
+        if (err) {
+                /* release sk on errors */
+                sock_orphan(sk);
+                sock_put(sk);
+        }
+
+ errout:
+        module_put(cp->prot->owner);
+        return err;
+}
+
+/*
+ * af_can tx path
+ */
+
+/**
+ * can_send - transmit a CAN frame (optional with local loopback)
+ * @skb: pointer to socket buffer with CAN frame in data section
+ * @loop: loopback for listeners on local CAN sockets (recommended default!)
+ *
+ * Return:
+ *  0 on success
+ *  -ENETDOWN when the selected interface is down
+ *  -ENOBUFS on full driver queue (see net_xmit_errno())
+ *  -ENOMEM when local loopback failed at calling skb_clone()
+ *  -EPERM when trying to send on a non-CAN interface
+ */
+int can_send(struct sk_buff *skb, int loop)
+{
+        int err;
+
+        if (skb->dev->type != ARPHRD_CAN) {
+                kfree_skb(skb);
+                return -EPERM;
+        }
+
+        if (!(skb->dev->flags & IFF_UP)) {
+                kfree_skb(skb);
+                return -ENETDOWN;
+        }
+
+        skb->protocol = htons(ETH_P_CAN);
+        skb_reset_network_header(skb);
+        skb_reset_transport_header(skb);
+
+        if (loop) {
+                /* local loopback of sent CAN frames */
+
+                /* indication for the CAN driver: do loopback */
+                skb->pkt_type = PACKET_LOOPBACK;
+
+                /*
+                 * The reference to the originating sock may be required
+                 * by the receiving socket to check whether the frame is
+                 * its own. Example: can_raw sockopt CAN_RAW_RECV_OWN_MSGS
+                 * Therefore we have to ensure that skb->sk remains the
+                 * reference to the originating sock by restoring skb->sk
+                 * after each skb_clone() or skb_orphan() usage.
+                 */
+
+                if (!(skb->dev->flags & IFF_ECHO)) {
+                        /*
+                         * If the interface is not capable to do loopback
+                         * itself, we do it here.
+                         */
+                        struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
+
+                        if (!newskb) {
+                                kfree_skb(skb);
+                                return -ENOMEM;
+                        }
+
+                        newskb->sk = skb->sk;
+                        newskb->ip_summed = CHECKSUM_UNNECESSARY;
+                        newskb->pkt_type = PACKET_BROADCAST;
+                        netif_rx(newskb);
+                }
+        } else {
+                /* indication for the CAN driver: no loopback required */
+                skb->pkt_type = PACKET_HOST;
+        }
+
+        /* send to netdevice */
+        err = dev_queue_xmit(skb);
+        if (err > 0)
+                err = net_xmit_errno(err);
+
+        /* update statistics */
+        can_stats.tx_frames++;
+        can_stats.tx_frames_delta++;
+
+        return err;
+}
+EXPORT_SYMBOL(can_send);
+
+/*
+ * af_can rx path
+ */
+
+static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
+{
+        struct dev_rcv_lists *d = NULL;
+        struct hlist_node *n;
+
+        /*
+         * find receive list for this device
+         *
+         * The hlist_for_each_entry*() macros curse through the list
+         * using the pointer variable n and set d to the containing
+         * struct in each list iteration.  Therefore, after list
+         * iteration, d is unmodified when the list is empty, and it
+         * points to last list element, when the list is non-empty
+         * but no match in the loop body is found.  I.e. d is *not*
+         * NULL when no match is found.  We can, however, use the
+         * cursor variable n to decide if a match was found.
+         */
+
+        hlist_for_each_entry_rcu(d, n, &can_rx_dev_list, list) {
+                if (d->dev == dev)
+                        break;
+        }
+
+        return n ? d : NULL;
+}
+
+static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
+                                        struct dev_rcv_lists *d)
+{
+        canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking */
+
+        /* filter error frames */
+        if (*mask & CAN_ERR_FLAG) {
+                /* clear CAN_ERR_FLAG in list entry */
+                *mask &= CAN_ERR_MASK;
+                return &d->rx[RX_ERR];
+        }
+
+        /* ensure valid values in can_mask */
+        if (*mask & CAN_EFF_FLAG)
+                *mask &= (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG);
+        else
+                *mask &= (CAN_SFF_MASK | CAN_RTR_FLAG);
+
+        /* reduce condition testing at receive time */
+        *can_id &= *mask;
+
+        /* inverse can_id/can_mask filter */
+        if (inv)
+                return &d->rx[RX_INV];
+
+        /* mask == 0 => no condition testing at receive time */
+        if (!(*mask))
+                return &d->rx[RX_ALL];
+
+        /* use extra filterset for the subscription of exactly *ONE* can_id */
+        if (*can_id & CAN_EFF_FLAG) {
+                if (*mask == (CAN_EFF_MASK | CAN_EFF_FLAG)) {
+                        /* RFC: a use-case for hash-tables in the future? */
+                        return &d->rx[RX_EFF];
+                }
+        } else {
+                if (*mask == CAN_SFF_MASK)
+                        return &d->rx_sff[*can_id];
+        }
+
+        /* default: filter via can_id/can_mask */
+        return &d->rx[RX_FIL];
+}
+
+/**
+ * can_rx_register - subscribe CAN frames from a specific interface
+ * @dev: pointer to netdevice (NULL => subcribe from 'all' CAN devices list)
+ * @can_id: CAN identifier (see description)
+ * @mask: CAN mask (see description)
+ * @func: callback function on filter match
+ * @data: returned parameter for callback function
+ * @ident: string for calling module indentification
+ *
+ * Description:
+ *  Invokes the callback function with the received sk_buff and the given
+ *  parameter 'data' on a matching receive filter. A filter matches, when
+ *
+ *          <received_can_id> & mask == can_id & mask
+ *
+ *  The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
+ *  filter for error frames (CAN_ERR_FLAG bit set in mask).
+ *
+ * Return:
+ *  0 on success
+ *  -ENOMEM on missing cache mem to create subscription entry
+ *  -ENODEV unknown device
+ */
+int can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
+                    void (*func)(struct sk_buff *, void *), void *data,
+                    char *ident)
+{
+        struct receiver *r;
+        struct hlist_head *rl;
+        struct dev_rcv_lists *d;
+        int err = 0;
+
+        /* insert new receiver  (dev,canid,mask) -> (func,data) */
+
+        r = kmem_cache_alloc(rcv_cache, GFP_KERNEL);
+        if (!r)
+                return -ENOMEM;
+
+        spin_lock(&can_rcvlists_lock);
+
+        d = find_dev_rcv_lists(dev);
+        if (d) {
+                rl = find_rcv_list(&can_id, &mask, d);
+
+                r->can_id  = can_id;
+                r->mask    = mask;
+                r->matches = 0;
+                r->func    = func;
+                r->data    = data;
+                r->ident   = ident;
+
+                hlist_add_head_rcu(&r->list, rl);
+                d->entries++;
+
+                can_pstats.rcv_entries++;
+                if (can_pstats.rcv_entries_max < can_pstats.rcv_entries)
+                        can_pstats.rcv_entries_max = can_pstats.rcv_entries;
+        } else {
+                kmem_cache_free(rcv_cache, r);
+                err = -ENODEV;
+        }
+
+        spin_unlock(&can_rcvlists_lock);
+
+        return err;
+}
+EXPORT_SYMBOL(can_rx_register);
+
+/*
+ * can_rx_delete_device - rcu callback for dev_rcv_lists structure removal
+ */
+static void can_rx_delete_device(struct rcu_head *rp)
+{
+        struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
+
+        kfree(d);
+}
+
+/*
+ * can_rx_delete_receiver - rcu callback for single receiver entry removal
+ */
+static void can_rx_delete_receiver(struct rcu_head *rp)
+{
+        struct receiver *r = container_of(rp, struct receiver, rcu);
+
+        kmem_cache_free(rcv_cache, r);
+}
+
+/**
+ * can_rx_unregister - unsubscribe CAN frames from a specific interface
+ * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
+ * @can_id: CAN identifier
+ * @mask: CAN mask
+ * @func: callback function on filter match
+ * @data: returned parameter for callback function
+ *
+ * Description:
+ *  Removes subscription entry depending on given (subscription) values.
+ */
+void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
+                       void (*func)(struct sk_buff *, void *), void *data)
+{
+        struct receiver *r = NULL;
+        struct hlist_head *rl;
+        struct hlist_node *next;
+        struct dev_rcv_lists *d;
+
+        spin_lock(&can_rcvlists_lock);
+
+        d = find_dev_rcv_lists(dev);
+        if (!d) {
+                printk(KERN_ERR "BUG: receive list not found for "
+                       "dev %s, id %03X, mask %03X\n",
+                       DNAME(dev), can_id, mask);
+                goto out;
+        }
+
+        rl = find_rcv_list(&can_id, &mask, d);
+
+        /*
+         * Search the receiver list for the item to delete.  This should
+         * exist, since no receiver may be unregistered that hasn't
+         * been registered before.
+         */
+
+        hlist_for_each_entry_rcu(r, next, rl, list) {
+                if (r->can_id == can_id && r->mask == mask
+                    && r->func == func && r->data == data)
+                        break;
+        }
+
+        /*
+         * Check for bugs in CAN protocol implementations:
+         * If no matching list item was found, the list cursor variable next
+         * will be NULL, while r will point to the last item of the list.
+         */
+
+        if (!next) {
+                printk(KERN_ERR "BUG: receive list entry not found for "
+                       "dev %s, id %03X, mask %03X\n",
+                       DNAME(dev), can_id, mask);
+                r = NULL;
+                d = NULL;
+                goto out;
+        }
+
+        hlist_del_rcu(&r->list);
+        d->entries--;
+
+        if (can_pstats.rcv_entries > 0)
+                can_pstats.rcv_entries--;
+
+        /* remove device structure requested by NETDEV_UNREGISTER */
+        if (d->remove_on_zero_entries && !d->entries)
+                hlist_del_rcu(&d->list);
+        else
+                d = NULL;
+
+ out:
+        spin_unlock(&can_rcvlists_lock);
+
+        /* schedule the receiver item for deletion */
+        if (r)
+                call_rcu(&r->rcu, can_rx_delete_receiver);
+
+        /* schedule the device structure for deletion */
+        if (d)
+                call_rcu(&d->rcu, can_rx_delete_device);
+}
+EXPORT_SYMBOL(can_rx_unregister);
+
+static inline void deliver(struct sk_buff *skb, struct receiver *r)
+{
+        struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
+
+        if (clone) {
+                clone->sk = skb->sk;
+                r->func(clone, r->data);
+                r->matches++;
+        }
+}
+
+static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
+{
+        struct receiver *r;
+        struct hlist_node *n;
+        int matches = 0;
+        struct can_frame *cf = (struct can_frame *)skb->data;
+        canid_t can_id = cf->can_id;
+
+        if (d->entries == 0)
+                return 0;
+
+        if (can_id & CAN_ERR_FLAG) {
+                /* check for error frame entries only */
+                hlist_for_each_entry_rcu(r, n, &d->rx[RX_ERR], list) {
+                        if (can_id & r->mask) {
+                                deliver(skb, r);
+                                matches++;
+                        }
+                }
+                return matches;
+        }
+
+        /* check for unfiltered entries */
+        hlist_for_each_entry_rcu(r, n, &d->rx[RX_ALL], list) {
+                deliver(skb, r);
+                matches++;
+        }
+
+        /* check for can_id/mask entries */
+        hlist_for_each_entry_rcu(r, n, &d->rx[RX_FIL], list) {
+                if ((can_id & r->mask) == r->can_id) {
+                        deliver(skb, r);
+                        matches++;
+                }
+        }
+
+        /* check for inverted can_id/mask entries */
+        hlist_for_each_entry_rcu(r, n, &d->rx[RX_INV], list) {
+                if ((can_id & r->mask) != r->can_id) {
+                        deliver(skb, r);
+                        matches++;
+                }
+        }
+
+        /* check CAN_ID specific entries */
+        if (can_id & CAN_EFF_FLAG) {
+                hlist_for_each_entry_rcu(r, n, &d->rx[RX_EFF], list) {
+                        if (r->can_id == can_id) {
+                                deliver(skb, r);
+                                matches++;
+                        }
+                }
+        } else {
+                can_id &= CAN_SFF_MASK;
+                hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
+                        deliver(skb, r);
+                        matches++;
+                }
+        }
+
+        return matches;
+}
+
+static int can_rcv(struct sk_buff *skb, struct net_device *dev,
+                   struct packet_type *pt, struct net_device *orig_dev)
+{
+        struct dev_rcv_lists *d;
+        int matches;
+
+        if (dev->type != ARPHRD_CAN || dev->nd_net != &init_net) {
+                kfree_skb(skb);
+                return 0;
+        }
+
+        /* update statistics */
+        can_stats.rx_frames++;
+        can_stats.rx_frames_delta++;
+
+        rcu_read_lock();
+
+        /* deliver the packet to sockets listening on all devices */
+        matches = can_rcv_filter(&can_rx_alldev_list, skb);
+
+        /* find receive list for this device */
+        d = find_dev_rcv_lists(dev);
+        if (d)
+                matches += can_rcv_filter(d, skb);
+
+        rcu_read_unlock();
+
+        /* free the skbuff allocated by the netdevice driver */
+        kfree_skb(skb);
+
+        if (matches > 0) {
+                can_stats.matches++;
+                can_stats.matches_delta++;
+        }
+
+        return 0;
+}
+
+/*
+ * af_can protocol functions
+ */
+
+/**
+ * can_proto_register - register CAN transport protocol
+ * @cp: pointer to CAN protocol structure
+ *
+ * Return:
+ *  0 on success
+ *  -EINVAL invalid (out of range) protocol number
+ *  -EBUSY  protocol already in use
+ *  -ENOBUF if proto_register() fails
+ */
+int can_proto_register(struct can_proto *cp)
+{
+        int proto = cp->protocol;
+        int err = 0;
+
+        if (proto < 0 || proto >= CAN_NPROTO) {
+                printk(KERN_ERR "can: protocol number %d out of range\n",
+                       proto);
+                return -EINVAL;
+        }
+
+        spin_lock(&proto_tab_lock);
+        if (proto_tab[proto]) {
+                printk(KERN_ERR "can: protocol %d already registered\n",
+                       proto);
+                err = -EBUSY;
+                goto errout;
+        }
+
+        err = proto_register(cp->prot, 0);
+        if (err < 0)
+                goto errout;
+
+        proto_tab[proto] = cp;
+
+        /* use generic ioctl function if the module doesn't bring its own */
+        if (!cp->ops->ioctl)
+                cp->ops->ioctl = can_ioctl;
+
+ errout:
+        spin_unlock(&proto_tab_lock);
+
+        return err;
+}
+EXPORT_SYMBOL(can_proto_register);
+
+/**
+ * can_proto_unregister - unregister CAN transport protocol
+ * @cp: pointer to CAN protocol structure
+ */
+void can_proto_unregister(struct can_proto *cp)
+{
+        int proto = cp->protocol;
+
+        spin_lock(&proto_tab_lock);
+        if (!proto_tab[proto]) {
+                printk(KERN_ERR "BUG: can: protocol %d is not registered\n",
+                       proto);
+        }
+        proto_unregister(cp->prot);
+        proto_tab[proto] = NULL;
+        spin_unlock(&proto_tab_lock);
+}
+EXPORT_SYMBOL(can_proto_unregister);
+
+/*
+ * af_can notifier to create/remove CAN netdevice specific structs
+ */
+static int can_notifier(struct notifier_block *nb, unsigned long msg,
+                        void *data)
+{
+        struct net_device *dev = (struct net_device *)data;
+        struct dev_rcv_lists *d;
+
+        if (dev->nd_net != &init_net)
+                return NOTIFY_DONE;
+
+        if (dev->type != ARPHRD_CAN)
+                return NOTIFY_DONE;
+
+        switch (msg) {
+
+        case NETDEV_REGISTER:
+
+                /*
+                 * create new dev_rcv_lists for this device
+                 *
+                 * N.B. zeroing the struct is the correct initialization
+                 * for the embedded hlist_head structs.
+                 * Another list type, e.g. list_head, would require
+                 * explicit initialization.
+                 */
+
+                d = kzalloc(sizeof(*d), GFP_KERNEL);
+                if (!d) {
+                        printk(KERN_ERR
+                               "can: allocation of receive list failed\n");
+                        return NOTIFY_DONE;
+                }
+                d->dev = dev;
+
+                spin_lock(&can_rcvlists_lock);
+                hlist_add_head_rcu(&d->list, &can_rx_dev_list);
+                spin_unlock(&can_rcvlists_lock);
+
+                break;
+
+        case NETDEV_UNREGISTER:
+                spin_lock(&can_rcvlists_lock);
+
+                d = find_dev_rcv_lists(dev);
+                if (d) {
+                        if (d->entries) {
+                                d->remove_on_zero_entries = 1;
+                                d = NULL;
+                        } else
+                                hlist_del_rcu(&d->list);
+                } else
+                        printk(KERN_ERR "can: notifier: receive list not "
+                               "found for dev %s\n", dev->name);
+
+                spin_unlock(&can_rcvlists_lock);
+
+                if (d)
+                        call_rcu(&d->rcu, can_rx_delete_device);
+
+                break;
+        }
+
+        return NOTIFY_DONE;
+}
+
+/*
+ * af_can module init/exit functions
+ */
+
+static struct packet_type can_packet __read_mostly = {
+        .type = __constant_htons(ETH_P_CAN),
+        .dev  = NULL,
+        .func = can_rcv,
+};
+
+static struct net_proto_family can_family_ops __read_mostly = {
+        .family = PF_CAN,
+        .create = can_create,
+        .owner  = THIS_MODULE,
+};
+
+/* notifier block for netdevice event */
+static struct notifier_block can_netdev_notifier __read_mostly = {
+        .notifier_call = can_notifier,
+};
+
+static __init int can_init(void)
+{
+        printk(banner);
+
+        rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
+                                      0, 0, NULL);
+        if (!rcv_cache)
+                return -ENOMEM;
+
+        /*
+         * Insert can_rx_alldev_list for reception on all devices.
+         * This struct is zero initialized which is correct for the
+         * embedded hlist heads, the dev pointer, and the entries counter.
+         */
+
+        spin_lock(&can_rcvlists_lock);
+        hlist_add_head_rcu(&can_rx_alldev_list.list, &can_rx_dev_list);
+        spin_unlock(&can_rcvlists_lock);
+
+        if (stats_timer) {
+                /* the statistics are updated every second (timer triggered) */
+                setup_timer(&can_stattimer, can_stat_update, 0);
+                mod_timer(&can_stattimer, round_jiffies(jiffies + HZ));
+        } else
+                can_stattimer.function = NULL;
+
+        can_init_proc();
+
+        /* protocol register */
+        sock_register(&can_family_ops);
+        register_netdevice_notifier(&can_netdev_notifier);
+        dev_add_pack(&can_packet);
+
+        return 0;
+}
+
+static __exit void can_exit(void)
+{
+        struct dev_rcv_lists *d;
+        struct hlist_node *n, *next;
+
+        if (stats_timer)
+                del_timer(&can_stattimer);
+
+        can_remove_proc();
+
+        /* protocol unregister */
+        dev_remove_pack(&can_packet);
+        unregister_netdevice_notifier(&can_netdev_notifier);
+        sock_unregister(PF_CAN);
+
+        /* remove can_rx_dev_list */
+        spin_lock(&can_rcvlists_lock);
+        hlist_del(&can_rx_alldev_list.list);
+        hlist_for_each_entry_safe(d, n, next, &can_rx_dev_list, list) {
+                hlist_del(&d->list);
+                kfree(d);
+        }
+        spin_unlock(&can_rcvlists_lock);
+
+        kmem_cache_destroy(rcv_cache);
+}
+
+module_init(can_init);
+module_exit(can_exit);