Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 896 insertions, 0 deletions

diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
new file mode 100644
index 00000000000..4eeaf88c1e9
--- /dev/null
+++ b/arch/um/drivers/net_kern.c
@@ -0,0 +1,896 @@
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include "linux/config.h"
+#include "linux/kernel.h"
+#include "linux/netdevice.h"
+#include "linux/rtnetlink.h"
+#include "linux/skbuff.h"
+#include "linux/socket.h"
+#include "linux/spinlock.h"
+#include "linux/module.h"
+#include "linux/init.h"
+#include "linux/etherdevice.h"
+#include "linux/list.h"
+#include "linux/inetdevice.h"
+#include "linux/ctype.h"
+#include "linux/bootmem.h"
+#include "linux/ethtool.h"
+#include "asm/uaccess.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "mconsole_kern.h"
+#include "init.h"
+#include "irq_user.h"
+#include "irq_kern.h"
+
+#define DRIVER_NAME "uml-netdev"
+
+static DEFINE_SPINLOCK(opened_lock);
+LIST_HEAD(opened);
+
+static int uml_net_rx(struct net_device *dev)
+{
+	struct uml_net_private *lp = dev->priv;
+	int pkt_len;
+	struct sk_buff *skb;
+
+	/* If we can't allocate memory, try again next round. */
+	skb = dev_alloc_skb(dev->mtu);
+	if (skb == NULL) {
+		lp->stats.rx_dropped++;
+		return 0;
+	}
+
+	skb->dev = dev;
+	skb_put(skb, dev->mtu);
+	skb->mac.raw = skb->data;
+	pkt_len = (*lp->read)(lp->fd, &skb, lp);
+
+	if (pkt_len > 0) {
+		skb_trim(skb, pkt_len);
+		skb->protocol = (*lp->protocol)(skb);
+		netif_rx(skb);
+
+		lp->stats.rx_bytes += skb->len;
+		lp->stats.rx_packets++;
+		return pkt_len;
+	}
+
+	kfree_skb(skb);
+	return pkt_len;
+}
+
+irqreturn_t uml_net_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct net_device *dev = dev_id;
+	struct uml_net_private *lp = dev->priv;
+	int err;
+
+	if(!netif_running(dev))
+		return(IRQ_NONE);
+
+	spin_lock(&lp->lock);
+	while((err = uml_net_rx(dev)) > 0) ;
+	if(err < 0) {
+		printk(KERN_ERR 
+		       "Device '%s' read returned %d, shutting it down\n", 
+		       dev->name, err);
+		dev_close(dev);
+		goto out;
+	}
+	reactivate_fd(lp->fd, UM_ETH_IRQ);
+
+ out:
+	spin_unlock(&lp->lock);
+	return(IRQ_HANDLED);
+}
+
+static int uml_net_open(struct net_device *dev)
+{
+	struct uml_net_private *lp = dev->priv;
+	char addr[sizeof("255.255.255.255\0")];
+	int err;
+
+	spin_lock(&lp->lock);
+
+	if(lp->fd >= 0){
+		err = -ENXIO;
+		goto out;
+	}
+
+	if(!lp->have_mac){
+ 		dev_ip_addr(dev, addr, &lp->mac[2]);
+ 		set_ether_mac(dev, lp->mac);
+	}
+
+	lp->fd = (*lp->open)(&lp->user);
+	if(lp->fd < 0){
+		err = lp->fd;
+		goto out;
+	}
+
+	err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
+			     SA_INTERRUPT | SA_SHIRQ, dev->name, dev);
+	if(err != 0){
+		printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
+		if(lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
+		lp->fd = -1;
+		err = -ENETUNREACH;
+	}
+
+	lp->tl.data = (unsigned long) &lp->user;
+	netif_start_queue(dev);
+
+	/* clear buffer - it can happen that the host side of the interface
+	 * is full when we get here.  In this case, new data is never queued,
+	 * SIGIOs never arrive, and the net never works.
+	 */
+	while((err = uml_net_rx(dev)) > 0) ;
+
+ out:
+	spin_unlock(&lp->lock);
+	return(err);
+}
+
+static int uml_net_close(struct net_device *dev)
+{
+	struct uml_net_private *lp = dev->priv;
+	
+	netif_stop_queue(dev);
+	spin_lock(&lp->lock);
+
+	free_irq_by_irq_and_dev(dev->irq, dev);
+	free_irq(dev->irq, dev);
+	if(lp->close != NULL)
+		(*lp->close)(lp->fd, &lp->user);
+	lp->fd = -1;
+
+	spin_unlock(&lp->lock);
+	return 0;
+}
+
+static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct uml_net_private *lp = dev->priv;
+	unsigned long flags;
+	int len;
+
+	netif_stop_queue(dev);
+
+	spin_lock_irqsave(&lp->lock, flags);
+
+	len = (*lp->write)(lp->fd, &skb, lp);
+
+	if(len == skb->len) {
+		lp->stats.tx_packets++;
+		lp->stats.tx_bytes += skb->len;
+		dev->trans_start = jiffies;
+		netif_start_queue(dev);
+
+		/* this is normally done in the interrupt when tx finishes */
+		netif_wake_queue(dev);
+	} 
+	else if(len == 0){
+		netif_start_queue(dev);
+		lp->stats.tx_dropped++;
+	}
+	else {
+		netif_start_queue(dev);
+		printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
+	}
+
+	spin_unlock_irqrestore(&lp->lock, flags);
+
+	dev_kfree_skb(skb);
+
+	return 0;
+}
+
+static struct net_device_stats *uml_net_get_stats(struct net_device *dev)
+{
+	struct uml_net_private *lp = dev->priv;
+	return &lp->stats;
+}
+
+static void uml_net_set_multicast_list(struct net_device *dev)
+{
+	if (dev->flags & IFF_PROMISC) return;
+	else if (dev->mc_count)	dev->flags |= IFF_ALLMULTI;
+	else dev->flags &= ~IFF_ALLMULTI;
+}
+
+static void uml_net_tx_timeout(struct net_device *dev)
+{
+	dev->trans_start = jiffies;
+	netif_wake_queue(dev);
+}
+
+static int uml_net_set_mac(struct net_device *dev, void *addr)
+{
+	struct uml_net_private *lp = dev->priv;
+	struct sockaddr *hwaddr = addr;
+
+	spin_lock(&lp->lock);
+	memcpy(dev->dev_addr, hwaddr->sa_data, ETH_ALEN);
+	spin_unlock(&lp->lock);
+
+	return(0);
+}
+
+static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct uml_net_private *lp = dev->priv;
+	int err = 0;
+
+	spin_lock(&lp->lock);
+
+	new_mtu = (*lp->set_mtu)(new_mtu, &lp->user);
+	if(new_mtu < 0){
+		err = new_mtu;
+		goto out;
+	}
+
+	dev->mtu = new_mtu;
+
+ out:
+	spin_unlock(&lp->lock);
+	return err;
+}
+
+static int uml_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	static const struct ethtool_drvinfo info = {
+		.cmd     = ETHTOOL_GDRVINFO,
+		.driver  = DRIVER_NAME,
+		.version = "42",
+	};
+	void *useraddr;
+	u32 ethcmd;
+
+	switch (cmd) {
+	case SIOCETHTOOL:
+		useraddr = ifr->ifr_data;
+		if (copy_from_user(&ethcmd, useraddr, sizeof(ethcmd)))
+			return -EFAULT;
+		switch (ethcmd) {
+		case ETHTOOL_GDRVINFO:
+			if (copy_to_user(useraddr, &info, sizeof(info)))
+				return -EFAULT;
+			return 0;
+		default:
+			return -EOPNOTSUPP;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+void uml_net_user_timer_expire(unsigned long _conn)
+{
+#ifdef undef
+	struct connection *conn = (struct connection *)_conn;
+
+	dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
+	do_connect(conn);
+#endif
+}
+
+static DEFINE_SPINLOCK(devices_lock);
+static struct list_head devices = LIST_HEAD_INIT(devices);
+
+static struct device_driver uml_net_driver = {
+	.name  = DRIVER_NAME,
+	.bus   = &platform_bus_type,
+};
+static int driver_registered;
+
+static int eth_configure(int n, void *init, char *mac,
+			 struct transport *transport)
+{
+	struct uml_net *device;
+	struct net_device *dev;
+	struct uml_net_private *lp;
+	int save, err, size;
+
+	size = transport->private_size + sizeof(struct uml_net_private) + 
+		sizeof(((struct uml_net_private *) 0)->user);
+
+	device = kmalloc(sizeof(*device), GFP_KERNEL);
+	if (device == NULL) {
+		printk(KERN_ERR "eth_configure failed to allocate uml_net\n");
+		return(1);
+	}
+
+	memset(device, 0, sizeof(*device));
+	INIT_LIST_HEAD(&device->list);
+	device->index = n;
+
+	spin_lock(&devices_lock);
+	list_add(&device->list, &devices);
+	spin_unlock(&devices_lock);
+
+	if (setup_etheraddr(mac, device->mac))
+		device->have_mac = 1;
+
+	printk(KERN_INFO "Netdevice %d ", n);
+	if (device->have_mac)
+		printk("(%02x:%02x:%02x:%02x:%02x:%02x) ",
+		       device->mac[0], device->mac[1],
+		       device->mac[2], device->mac[3],
+		       device->mac[4], device->mac[5]);
+	printk(": ");
+	dev = alloc_etherdev(size);
+	if (dev == NULL) {
+		printk(KERN_ERR "eth_configure: failed to allocate device\n");
+		return 1;
+	}
+
+	/* sysfs register */
+	if (!driver_registered) {
+		driver_register(&uml_net_driver);
+		driver_registered = 1;
+	}
+	device->pdev.id = n;
+	device->pdev.name = DRIVER_NAME;
+	platform_device_register(&device->pdev);
+	SET_NETDEV_DEV(dev,&device->pdev.dev);
+
+	/* If this name ends up conflicting with an existing registered
+	 * netdevice, that is OK, register_netdev{,ice}() will notice this
+	 * and fail.
+	 */
+	snprintf(dev->name, sizeof(dev->name), "eth%d", n);
+	device->dev = dev;
+
+	(*transport->kern->init)(dev, init);
+
+	dev->mtu = transport->user->max_packet;
+	dev->open = uml_net_open;
+	dev->hard_start_xmit = uml_net_start_xmit;
+	dev->stop = uml_net_close;
+	dev->get_stats = uml_net_get_stats;
+	dev->set_multicast_list = uml_net_set_multicast_list;
+	dev->tx_timeout = uml_net_tx_timeout;
+	dev->set_mac_address = uml_net_set_mac;
+	dev->change_mtu = uml_net_change_mtu;
+	dev->do_ioctl = uml_net_ioctl;
+	dev->watchdog_timeo = (HZ >> 1);
+	dev->irq = UM_ETH_IRQ;
+
+	rtnl_lock();
+	err = register_netdevice(dev);
+	rtnl_unlock();
+	if (err) {
+		device->dev = NULL;
+		/* XXX: should we call ->remove() here? */
+		free_netdev(dev);
+		return 1;
+	}
+	lp = dev->priv;
+
+	/* lp.user is the first four bytes of the transport data, which
+	 * has already been initialized.  This structure assignment will
+	 * overwrite that, so we make sure that .user gets overwritten with
+	 * what it already has.
+	 */
+	save = lp->user[0];
+	*lp = ((struct uml_net_private)
+		{ .list  		= LIST_HEAD_INIT(lp->list),
+		  .dev 			= dev,
+		  .fd 			= -1,
+		  .mac 			= { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
+		  .have_mac 		= device->have_mac,
+		  .protocol 		= transport->kern->protocol,
+		  .open 		= transport->user->open,
+		  .close 		= transport->user->close,
+		  .remove 		= transport->user->remove,
+		  .read 		= transport->kern->read,
+		  .write 		= transport->kern->write,
+		  .add_address 		= transport->user->add_address,
+		  .delete_address  	= transport->user->delete_address,
+		  .set_mtu 		= transport->user->set_mtu,
+		  .user  		= { save } });
+
+	init_timer(&lp->tl);
+	spin_lock_init(&lp->lock);
+	lp->tl.function = uml_net_user_timer_expire;
+	if (lp->have_mac)
+		memcpy(lp->mac, device->mac, sizeof(lp->mac));
+
+	if (transport->user->init) 
+		(*transport->user->init)(&lp->user, dev);
+
+	if (device->have_mac)
+		set_ether_mac(dev, device->mac);
+
+	spin_lock(&opened_lock);
+	list_add(&lp->list, &opened);
+	spin_unlock(&opened_lock);
+
+	return(0);
+}
+
+static struct uml_net *find_device(int n)
+{
+	struct uml_net *device;
+	struct list_head *ele;
+
+	spin_lock(&devices_lock);
+	list_for_each(ele, &devices){
+		device = list_entry(ele, struct uml_net, list);
+		if(device->index == n)
+			goto out;
+	}
+	device = NULL;
+ out:
+	spin_unlock(&devices_lock);
+	return(device);
+}
+
+static int eth_parse(char *str, int *index_out, char **str_out)
+{
+	char *end;
+	int n;
+
+	n = simple_strtoul(str, &end, 0);
+	if(end == str){
+		printk(KERN_ERR "eth_setup: Failed to parse '%s'\n", str);
+		return(1);
+	}
+	if(n < 0){
+		printk(KERN_ERR "eth_setup: device %d is negative\n", n);
+		return(1);
+	}
+	str = end;
+	if(*str != '='){
+		printk(KERN_ERR 
+		       "eth_setup: expected '=' after device number\n");
+		return(1);
+	}
+	str++;
+	if(find_device(n)){
+		printk(KERN_ERR "eth_setup: Device %d already configured\n",
+		       n);
+		return(1);
+	}
+	if(index_out) *index_out = n;
+	*str_out = str;
+	return(0);
+}
+
+struct eth_init {
+	struct list_head list;
+	char *init;
+	int index;
+};
+
+/* Filled in at boot time.  Will need locking if the transports become
+ * modular.
+ */
+struct list_head transports = LIST_HEAD_INIT(transports);
+
+/* Filled in during early boot */
+struct list_head eth_cmd_line = LIST_HEAD_INIT(eth_cmd_line);
+
+static int check_transport(struct transport *transport, char *eth, int n,
+			   void **init_out, char **mac_out)
+{
+	int len;
+
+	len = strlen(transport->name);
+	if(strncmp(eth, transport->name, len))
+		return(0);
+
+	eth += len;
+	if(*eth == ',')
+		eth++;
+	else if(*eth != '\0')
+		return(0);
+
+	*init_out = kmalloc(transport->setup_size, GFP_KERNEL);
+	if(*init_out == NULL)
+		return(1);
+
+	if(!transport->setup(eth, mac_out, *init_out)){
+		kfree(*init_out);
+		*init_out = NULL;
+	}
+	return(1);
+}
+
+void register_transport(struct transport *new)
+{
+	struct list_head *ele, *next;
+	struct eth_init *eth;
+	void *init;
+	char *mac = NULL;
+	int match;
+
+	list_add(&new->list, &transports);
+
+	list_for_each_safe(ele, next, &eth_cmd_line){
+		eth = list_entry(ele, struct eth_init, list);
+		match = check_transport(new, eth->init, eth->index, &init,
+					&mac);
+		if(!match)
+			continue;
+		else if(init != NULL){
+			eth_configure(eth->index, init, mac, new);
+			kfree(init);
+		}
+		list_del(&eth->list);
+	}
+}
+
+static int eth_setup_common(char *str, int index)
+{
+	struct list_head *ele;
+	struct transport *transport;
+	void *init;
+	char *mac = NULL;
+
+	list_for_each(ele, &transports){
+		transport = list_entry(ele, struct transport, list);
+	        if(!check_transport(transport, str, index, &init, &mac))
+			continue;
+		if(init != NULL){
+			eth_configure(index, init, mac, transport);
+			kfree(init);
+		}
+		return(1);
+	}
+	return(0);
+}
+
+static int eth_setup(char *str)
+{
+	struct eth_init *new;
+	int n, err;
+
+	err = eth_parse(str, &n, &str);
+	if(err) return(1);
+
+	new = alloc_bootmem(sizeof(new));
+	if (new == NULL){
+		printk("eth_init : alloc_bootmem failed\n");
+		return(1);
+	}
+
+	INIT_LIST_HEAD(&new->list);
+	new->index = n;
+	new->init = str;
+
+	list_add_tail(&new->list, &eth_cmd_line);
+	return(1);
+}
+
+__setup("eth", eth_setup);
+__uml_help(eth_setup,
+"eth[0-9]+=<transport>,<options>\n"
+"    Configure a network device.\n\n"
+);
+
+#if 0
+static int eth_init(void)
+{
+	struct list_head *ele, *next;
+	struct eth_init *eth;
+
+	list_for_each_safe(ele, next, &eth_cmd_line){
+		eth = list_entry(ele, struct eth_init, list);
+
+		if(eth_setup_common(eth->init, eth->index))
+			list_del(&eth->list);
+	}
+	
+	return(1);
+}
+__initcall(eth_init);
+#endif
+
+static int net_config(char *str)
+{
+	int n, err;
+
+	err = eth_parse(str, &n, &str);
+	if(err) return(err);
+
+	str = uml_strdup(str);
+	if(str == NULL){
+		printk(KERN_ERR "net_config failed to strdup string\n");
+		return(-1);
+	}
+	err = !eth_setup_common(str, n);
+	if(err) 
+		kfree(str);
+	return(err);
+}
+
+static int net_remove(char *str)
+{
+	struct uml_net *device;
+	struct net_device *dev;
+	struct uml_net_private *lp;
+	char *end;
+	int n;
+
+	n = simple_strtoul(str, &end, 0);
+	if((*end != '\0') || (end == str))
+		return(-1);
+
+	device = find_device(n);
+	if(device == NULL)
+		return(0);
+
+	dev = device->dev;
+	lp = dev->priv;
+	if(lp->fd > 0) return(-1);
+	if(lp->remove != NULL) (*lp->remove)(&lp->user);
+	unregister_netdev(dev);
+	platform_device_unregister(&device->pdev);
+
+	list_del(&device->list);
+	kfree(device);
+	free_netdev(dev);
+	return(0);
+}
+
+static struct mc_device net_mc = {
+	.name		= "eth",
+	.config		= net_config,
+	.get_config	= NULL,
+	.remove		= net_remove,
+};
+
+static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
+			      void *ptr)
+{
+	struct in_ifaddr *ifa = ptr;
+	u32 addr = ifa->ifa_address;
+	u32 netmask = ifa->ifa_mask;
+	struct net_device *dev = ifa->ifa_dev->dev;
+	struct uml_net_private *lp;
+	void (*proc)(unsigned char *, unsigned char *, void *);
+	unsigned char addr_buf[4], netmask_buf[4];
+
+	if(dev->open != uml_net_open) return(NOTIFY_DONE);
+
+	lp = dev->priv;
+
+	proc = NULL;
+	switch (event){
+	case NETDEV_UP:
+		proc = lp->add_address;
+		break;
+	case NETDEV_DOWN:
+		proc = lp->delete_address;
+		break;
+	}
+	if(proc != NULL){
+		addr_buf[0] = addr & 0xff;
+		addr_buf[1] = (addr >> 8) & 0xff;
+		addr_buf[2] = (addr >> 16) & 0xff;
+		addr_buf[3] = addr >> 24;
+		netmask_buf[0] = netmask & 0xff;
+		netmask_buf[1] = (netmask >> 8) & 0xff;
+		netmask_buf[2] = (netmask >> 16) & 0xff;
+		netmask_buf[3] = netmask >> 24;
+		(*proc)(addr_buf, netmask_buf, &lp->user);
+	}
+	return(NOTIFY_DONE);
+}
+
+struct notifier_block uml_inetaddr_notifier = {
+	.notifier_call		= uml_inetaddr_event,
+};
+
+static int uml_net_init(void)
+{
+	struct list_head *ele;
+	struct uml_net_private *lp;	
+	struct in_device *ip;
+	struct in_ifaddr *in;
+
+	mconsole_register_dev(&net_mc);
+	register_inetaddr_notifier(&uml_inetaddr_notifier);
+
+	/* Devices may have been opened already, so the uml_inetaddr_notifier
+	 * didn't get a chance to run for them.  This fakes it so that
+	 * addresses which have already been set up get handled properly.
+	 */
+	list_for_each(ele, &opened){
+		lp = list_entry(ele, struct uml_net_private, list);
+		ip = lp->dev->ip_ptr;
+		if(ip == NULL) continue;
+		in = ip->ifa_list;
+		while(in != NULL){
+			uml_inetaddr_event(NULL, NETDEV_UP, in);
+			in = in->ifa_next;
+		}
+	}	
+
+	return(0);
+}
+
+__initcall(uml_net_init);
+
+static void close_devices(void)
+{
+	struct list_head *ele;
+	struct uml_net_private *lp;
+
+	list_for_each(ele, &opened){
+		lp = list_entry(ele, struct uml_net_private, list);
+		if((lp->close != NULL) && (lp->fd >= 0))
+			(*lp->close)(lp->fd, &lp->user);
+		if(lp->remove != NULL) (*lp->remove)(&lp->user);
+	}
+}
+
+__uml_exitcall(close_devices);
+
+int setup_etheraddr(char *str, unsigned char *addr)
+{
+	char *end;
+	int i;
+
+	if(str == NULL)
+		return(0);
+	for(i=0;i<6;i++){
+		addr[i] = simple_strtoul(str, &end, 16);
+		if((end == str) ||
+		   ((*end != ':') && (*end != ',') && (*end != '\0'))){
+			printk(KERN_ERR 
+			       "setup_etheraddr: failed to parse '%s' "
+			       "as an ethernet address\n", str);
+			return(0);
+		}
+		str = end + 1;
+	}
+	if(addr[0] & 1){
+		printk(KERN_ERR 
+		       "Attempt to assign a broadcast ethernet address to a "
+		       "device disallowed\n");
+		return(0);
+	}
+	return(1);
+}
+
+void dev_ip_addr(void *d, char *buf, char *bin_buf)
+{
+	struct net_device *dev = d;
+	struct in_device *ip = dev->ip_ptr;
+	struct in_ifaddr *in;
+	u32 addr;
+
+	if((ip == NULL) || ((in = ip->ifa_list) == NULL)){
+		printk(KERN_WARNING "dev_ip_addr - device not assigned an "
+		       "IP address\n");
+		return;
+	}
+	addr = in->ifa_address;
+	sprintf(buf, "%d.%d.%d.%d", addr & 0xff, (addr >> 8) & 0xff, 
+		(addr >> 16) & 0xff, addr >> 24);
+	if(bin_buf){
+		bin_buf[0] = addr & 0xff;
+		bin_buf[1] = (addr >> 8) & 0xff;
+		bin_buf[2] = (addr >> 16) & 0xff;
+		bin_buf[3] = addr >> 24;
+	}
+}
+
+void set_ether_mac(void *d, unsigned char *addr)
+{
+	struct net_device *dev = d;
+
+	memcpy(dev->dev_addr, addr, ETH_ALEN);	
+}
+
+struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra)
+{
+	if((skb != NULL) && (skb_tailroom(skb) < extra)){
+	  	struct sk_buff *skb2;
+
+		skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC);
+		dev_kfree_skb(skb);
+		skb = skb2;
+	}
+	if(skb != NULL) skb_put(skb, extra);
+	return(skb);
+}
+
+void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *, 
+					void *), 
+		    void *arg)
+{
+	struct net_device *dev = d;
+	struct in_device *ip = dev->ip_ptr;
+	struct in_ifaddr *in;
+	unsigned char address[4], netmask[4];
+
+	if(ip == NULL) return;
+	in = ip->ifa_list;
+	while(in != NULL){
+		address[0] = in->ifa_address & 0xff;
+		address[1] = (in->ifa_address >> 8) & 0xff;
+		address[2] = (in->ifa_address >> 16) & 0xff;
+		address[3] = in->ifa_address >> 24;
+		netmask[0] = in->ifa_mask & 0xff;
+		netmask[1] = (in->ifa_mask >> 8) & 0xff;
+		netmask[2] = (in->ifa_mask >> 16) & 0xff;
+		netmask[3] = in->ifa_mask >> 24;
+		(*cb)(address, netmask, arg);
+		in = in->ifa_next;
+	}
+}
+
+int dev_netmask(void *d, void *m)
+{
+	struct net_device *dev = d;
+	struct in_device *ip = dev->ip_ptr;
+	struct in_ifaddr *in;
+	__u32 *mask_out = m;
+
+	if(ip == NULL) 
+		return(1);
+
+	in = ip->ifa_list;
+	if(in == NULL) 
+		return(1);
+
+	*mask_out = in->ifa_mask;
+	return(0);
+}
+
+void *get_output_buffer(int *len_out)
+{
+	void *ret;
+
+	ret = (void *) __get_free_pages(GFP_KERNEL, 0);
+	if(ret) *len_out = PAGE_SIZE;
+	else *len_out = 0;
+	return(ret);
+}
+
+void free_output_buffer(void *buffer)
+{
+	free_pages((unsigned long) buffer, 0);
+}
+
+int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out, 
+		     char **gate_addr)
+{
+	char *remain;
+
+	remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
+	if(remain != NULL){
+		printk("tap_setup_common - Extra garbage on specification : "
+		       "'%s'\n", remain);
+		return(1);
+	}
+
+	return(0);
+}
+
+unsigned short eth_protocol(struct sk_buff *skb)
+{
+	return(eth_type_trans(skb, skb->dev));
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */