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/*
* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
* James Leu (jleu@mindspring.net).
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Copyright (C) 2001 by various other people who didn't put their name here.
* Licensed under the GPL.
*/
#include "linux/init.h"
#include <linux/netdevice.h>
#include "etap.h"
#include "net_kern.h"
struct ethertap_init {
char *dev_name;
char *gate_addr;
};
static void etap_init(struct net_device *dev, void *data)
{
struct uml_net_private *pri;
struct ethertap_data *epri;
struct ethertap_init *init = data;
pri = dev->priv;
epri = (struct ethertap_data *) pri->user;
epri->dev_name = init->dev_name;
epri->gate_addr = init->gate_addr;
epri->data_fd = -1;
epri->control_fd = -1;
epri->dev = dev;
printk("ethertap backend - %s", epri->dev_name);
if (epri->gate_addr != NULL)
printk(", IP = %s", epri->gate_addr);
printk("\n");
}
static int etap_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
{
int len;
*skb = ether_adjust_skb(*skb, ETH_HEADER_ETHERTAP);
if (*skb == NULL)
return -ENOMEM;
len = net_recvfrom(fd, skb_mac_header(*skb),
(*skb)->dev->mtu + 2 * ETH_HEADER_ETHERTAP);
if (len <= 0)
return len;
skb_pull(*skb, 2);
len -= 2;
return len;
}
static int etap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
{
if (skb_headroom(*skb) < 2) {
struct sk_buff *skb2;
skb2 = skb_realloc_headroom(*skb, 2);
dev_kfree_skb(*skb);
if (skb2 == NULL)
return -ENOMEM;
*skb = skb2;
}
skb_push(*skb, 2);
return net_send(fd, (*skb)->data, (*skb)->len);
}
const struct net_kern_info ethertap_kern_info = {
.init = etap_init,
.protocol = eth_protocol,
.read = etap_read,
.write = etap_write,
};
int ethertap_setup(char *str, char **mac_out, void *data)
{
struct ethertap_init *init = data;
*init = ((struct ethertap_init)
{ .dev_name = NULL,
.gate_addr = NULL });
if (tap_setup_common(str, "ethertap", &init->dev_name, mac_out,
&init->gate_addr))
return 0;
if (init->dev_name == NULL) {
printk(KERN_ERR "ethertap_setup : Missing tap device name\n");
return 0;
}
return 1;
}
static struct transport ethertap_transport = {
.list = LIST_HEAD_INIT(ethertap_transport.list),
.name = "ethertap",
.setup = ethertap_setup,
.user = ðertap_user_info,
.kern = ðertap_kern_info,
.private_size = sizeof(struct ethertap_data),
};
static int register_ethertap(void)
{
register_transport(ðertap_transport);
return 0;
}
late_initcall(register_ethertap);
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