2.6.25-rc7

 net

 can

diff --git a/net/can/af_can.c b/net/can/af_can.c
new file mode 100644
index 0000000..36b9f22
--- /dev/null
+++ b/net/can/af_can.c
@@ -0,0 +1,856 @@
+/*
+ * 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;
+   int err = 0;
+
+   sock->state = SS_UNCONNECTED;
+
+   if (protocol < 0 || protocol >= CAN_NPROTO)
+      return -EINVAL;
+
+   if (net != &init_net)
+      return -EAFNOSUPPORT;
+
+#ifdef CONFIG_KMOD
+   /* try to load protocol module, when CONFIG_KMOD is defined */
+   if (!proto_tab[protocol]) {
+      err = request_module("can-proto-%d", protocol);
+
+      /*
+       * In case of error we only print a message but don't
+       * return the error code immediately.  Below we will
+       * return -EPROTONOSUPPORT
+       */
+      if (err && printk_ratelimit())
+         printk(KERN_ERR "can: request_module "
+                "(can-proto-%d) failed.\n", protocol);
+   }
+#endif
+
+   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;
+   }
+
+   err = proto_register(cp->prot, 0);
+   if (err < 0)
+      return err;
+
+   spin_lock(&proto_tab_lock);
+   if (proto_tab[proto]) {
+      printk(KERN_ERR "can: protocol %d already registered\n",
+             proto);
+      err = -EBUSY;
+   } else {
+      proto_tab[proto] = cp;
+
+      /* use generic ioctl function if not defined by module */
+      if (!cp->ops->ioctl)
+         cp->ops->ioctl = can_ioctl;
+   }
+   spin_unlock(&proto_tab_lock);
+
+   if (err < 0)
+      proto_unregister(cp->prot);
+
+   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_tab[proto] = NULL;
+   spin_unlock(&proto_tab_lock);
+
+   proto_unregister(cp->prot);
+}
+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);