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