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authorLinus Torvalds <torvalds@linux-foundation.org>2008-01-29 22:54:01 +1100
committerLinus Torvalds <torvalds@linux-foundation.org>2008-01-29 22:54:01 +1100
commit0ba6c33bcddc64a54b5f1c25a696c4767dc76292 (patch)
tree62e616f97a4762d8e75bf732e4827af2d15d52c5 /drivers/net/can/vcan.c
parent21af0297c7e56024a5ccc4d8ad2a590f9ec371ba (diff)
parent85040bcb4643cba578839e953f25e2d1965d83d0 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.25
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.25: (1470 commits) [IPV6] ADDRLABEL: Fix double free on label deletion. [PPP]: Sparse warning fixes. [IPV4] fib_trie: remove unneeded NULL check [IPV4] fib_trie: More whitespace cleanup. [NET_SCHED]: Use nla_policy for attribute validation in ematches [NET_SCHED]: Use nla_policy for attribute validation in actions [NET_SCHED]: Use nla_policy for attribute validation in classifiers [NET_SCHED]: Use nla_policy for attribute validation in packet schedulers [NET_SCHED]: sch_api: introduce constant for rate table size [NET_SCHED]: Use typeful attribute parsing helpers [NET_SCHED]: Use typeful attribute construction helpers [NET_SCHED]: Use NLA_PUT_STRING for string dumping [NET_SCHED]: Use nla_nest_start/nla_nest_end [NET_SCHED]: Propagate nla_parse return value [NET_SCHED]: act_api: use PTR_ERR in tcf_action_init/tcf_action_get [NET_SCHED]: act_api: use nlmsg_parse [NET_SCHED]: act_api: fix netlink API conversion bug [NET_SCHED]: sch_netem: use nla_parse_nested_compat [NET_SCHED]: sch_atm: fix format string warning [NETNS]: Add namespace for ICMP replying code. ...
Diffstat (limited to 'drivers/net/can/vcan.c')
-rw-r--r--drivers/net/can/vcan.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c
new file mode 100644
index 00000000000..103f0f1df28
--- /dev/null
+++ b/drivers/net/can/vcan.c
@@ -0,0 +1,169 @@
+/*
+ * vcan.c - Virtual CAN interface
+ *
+ * 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/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/can.h>
+#include <net/rtnetlink.h>
+
+static __initdata const char banner[] =
+ KERN_INFO "vcan: Virtual CAN interface driver\n";
+
+MODULE_DESCRIPTION("virtual CAN interface");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
+
+
+/*
+ * CAN test feature:
+ * Enable the echo on driver level for testing the CAN core echo modes.
+ * See Documentation/networking/can.txt for details.
+ */
+
+static int echo; /* echo testing. Default: 0 (Off) */
+module_param(echo, bool, S_IRUGO);
+MODULE_PARM_DESC(echo, "Echo sent frames (for testing). Default: 0 (Off)");
+
+
+static void vcan_rx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct net_device_stats *stats = &dev->stats;
+
+ stats->rx_packets++;
+ stats->rx_bytes += skb->len;
+
+ skb->protocol = htons(ETH_P_CAN);
+ skb->pkt_type = PACKET_BROADCAST;
+ skb->dev = dev;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ netif_rx(skb);
+}
+
+static int vcan_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct net_device_stats *stats = &dev->stats;
+ int loop;
+
+ stats->tx_packets++;
+ stats->tx_bytes += skb->len;
+
+ /* set flag whether this packet has to be looped back */
+ loop = skb->pkt_type == PACKET_LOOPBACK;
+
+ if (!echo) {
+ /* no echo handling available inside this driver */
+
+ if (loop) {
+ /*
+ * only count the packets here, because the
+ * CAN core already did the echo for us
+ */
+ stats->rx_packets++;
+ stats->rx_bytes += skb->len;
+ }
+ kfree_skb(skb);
+ return NETDEV_TX_OK;
+ }
+
+ /* perform standard echo handling for CAN network interfaces */
+
+ if (loop) {
+ struct sock *srcsk = skb->sk;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ return NETDEV_TX_OK;
+
+ /* receive with packet counting */
+ skb->sk = srcsk;
+ vcan_rx(skb, dev);
+ } else {
+ /* no looped packets => no counting */
+ kfree_skb(skb);
+ }
+ return NETDEV_TX_OK;
+}
+
+static void vcan_setup(struct net_device *dev)
+{
+ dev->type = ARPHRD_CAN;
+ dev->mtu = sizeof(struct can_frame);
+ dev->hard_header_len = 0;
+ dev->addr_len = 0;
+ dev->tx_queue_len = 0;
+ dev->flags = IFF_NOARP;
+
+ /* set flags according to driver capabilities */
+ if (echo)
+ dev->flags |= IFF_ECHO;
+
+ dev->hard_start_xmit = vcan_tx;
+ dev->destructor = free_netdev;
+}
+
+static struct rtnl_link_ops vcan_link_ops __read_mostly = {
+ .kind = "vcan",
+ .setup = vcan_setup,
+};
+
+static __init int vcan_init_module(void)
+{
+ printk(banner);
+
+ if (echo)
+ printk(KERN_INFO "vcan: enabled echo on driver level.\n");
+
+ return rtnl_link_register(&vcan_link_ops);
+}
+
+static __exit void vcan_cleanup_module(void)
+{
+ rtnl_link_unregister(&vcan_link_ops);
+}
+
+module_init(vcan_init_module);
+module_exit(vcan_cleanup_module);