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/arch/um/drivers/net_kern.c

https://bitbucket.org/evzijst/gittest
C | 896 lines | 714 code | 141 blank | 41 comment | 127 complexity | 8bba134a9a9eec68e534342a26a429e8 MD5 | raw file
  1/*
  2 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
  3 * James Leu (jleu@mindspring.net).
  4 * Copyright (C) 2001 by various other people who didn't put their name here.
  5 * Licensed under the GPL.
  6 */
  7
  8#include "linux/config.h"
  9#include "linux/kernel.h"
 10#include "linux/netdevice.h"
 11#include "linux/rtnetlink.h"
 12#include "linux/skbuff.h"
 13#include "linux/socket.h"
 14#include "linux/spinlock.h"
 15#include "linux/module.h"
 16#include "linux/init.h"
 17#include "linux/etherdevice.h"
 18#include "linux/list.h"
 19#include "linux/inetdevice.h"
 20#include "linux/ctype.h"
 21#include "linux/bootmem.h"
 22#include "linux/ethtool.h"
 23#include "asm/uaccess.h"
 24#include "user_util.h"
 25#include "kern_util.h"
 26#include "net_kern.h"
 27#include "net_user.h"
 28#include "mconsole_kern.h"
 29#include "init.h"
 30#include "irq_user.h"
 31#include "irq_kern.h"
 32
 33#define DRIVER_NAME "uml-netdev"
 34
 35static DEFINE_SPINLOCK(opened_lock);
 36LIST_HEAD(opened);
 37
 38static int uml_net_rx(struct net_device *dev)
 39{
 40	struct uml_net_private *lp = dev->priv;
 41	int pkt_len;
 42	struct sk_buff *skb;
 43
 44	/* If we can't allocate memory, try again next round. */
 45	skb = dev_alloc_skb(dev->mtu);
 46	if (skb == NULL) {
 47		lp->stats.rx_dropped++;
 48		return 0;
 49	}
 50
 51	skb->dev = dev;
 52	skb_put(skb, dev->mtu);
 53	skb->mac.raw = skb->data;
 54	pkt_len = (*lp->read)(lp->fd, &skb, lp);
 55
 56	if (pkt_len > 0) {
 57		skb_trim(skb, pkt_len);
 58		skb->protocol = (*lp->protocol)(skb);
 59		netif_rx(skb);
 60
 61		lp->stats.rx_bytes += skb->len;
 62		lp->stats.rx_packets++;
 63		return pkt_len;
 64	}
 65
 66	kfree_skb(skb);
 67	return pkt_len;
 68}
 69
 70irqreturn_t uml_net_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 71{
 72	struct net_device *dev = dev_id;
 73	struct uml_net_private *lp = dev->priv;
 74	int err;
 75
 76	if(!netif_running(dev))
 77		return(IRQ_NONE);
 78
 79	spin_lock(&lp->lock);
 80	while((err = uml_net_rx(dev)) > 0) ;
 81	if(err < 0) {
 82		printk(KERN_ERR 
 83		       "Device '%s' read returned %d, shutting it down\n", 
 84		       dev->name, err);
 85		dev_close(dev);
 86		goto out;
 87	}
 88	reactivate_fd(lp->fd, UM_ETH_IRQ);
 89
 90 out:
 91	spin_unlock(&lp->lock);
 92	return(IRQ_HANDLED);
 93}
 94
 95static int uml_net_open(struct net_device *dev)
 96{
 97	struct uml_net_private *lp = dev->priv;
 98	char addr[sizeof("255.255.255.255\0")];
 99	int err;
100
101	spin_lock(&lp->lock);
102
103	if(lp->fd >= 0){
104		err = -ENXIO;
105		goto out;
106	}
107
108	if(!lp->have_mac){
109 		dev_ip_addr(dev, addr, &lp->mac[2]);
110 		set_ether_mac(dev, lp->mac);
111	}
112
113	lp->fd = (*lp->open)(&lp->user);
114	if(lp->fd < 0){
115		err = lp->fd;
116		goto out;
117	}
118
119	err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
120			     SA_INTERRUPT | SA_SHIRQ, dev->name, dev);
121	if(err != 0){
122		printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
123		if(lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
124		lp->fd = -1;
125		err = -ENETUNREACH;
126	}
127
128	lp->tl.data = (unsigned long) &lp->user;
129	netif_start_queue(dev);
130
131	/* clear buffer - it can happen that the host side of the interface
132	 * is full when we get here.  In this case, new data is never queued,
133	 * SIGIOs never arrive, and the net never works.
134	 */
135	while((err = uml_net_rx(dev)) > 0) ;
136
137 out:
138	spin_unlock(&lp->lock);
139	return(err);
140}
141
142static int uml_net_close(struct net_device *dev)
143{
144	struct uml_net_private *lp = dev->priv;
145	
146	netif_stop_queue(dev);
147	spin_lock(&lp->lock);
148
149	free_irq_by_irq_and_dev(dev->irq, dev);
150	free_irq(dev->irq, dev);
151	if(lp->close != NULL)
152		(*lp->close)(lp->fd, &lp->user);
153	lp->fd = -1;
154
155	spin_unlock(&lp->lock);
156	return 0;
157}
158
159static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
160{
161	struct uml_net_private *lp = dev->priv;
162	unsigned long flags;
163	int len;
164
165	netif_stop_queue(dev);
166
167	spin_lock_irqsave(&lp->lock, flags);
168
169	len = (*lp->write)(lp->fd, &skb, lp);
170
171	if(len == skb->len) {
172		lp->stats.tx_packets++;
173		lp->stats.tx_bytes += skb->len;
174		dev->trans_start = jiffies;
175		netif_start_queue(dev);
176
177		/* this is normally done in the interrupt when tx finishes */
178		netif_wake_queue(dev);
179	} 
180	else if(len == 0){
181		netif_start_queue(dev);
182		lp->stats.tx_dropped++;
183	}
184	else {
185		netif_start_queue(dev);
186		printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
187	}
188
189	spin_unlock_irqrestore(&lp->lock, flags);
190
191	dev_kfree_skb(skb);
192
193	return 0;
194}
195
196static struct net_device_stats *uml_net_get_stats(struct net_device *dev)
197{
198	struct uml_net_private *lp = dev->priv;
199	return &lp->stats;
200}
201
202static void uml_net_set_multicast_list(struct net_device *dev)
203{
204	if (dev->flags & IFF_PROMISC) return;
205	else if (dev->mc_count)	dev->flags |= IFF_ALLMULTI;
206	else dev->flags &= ~IFF_ALLMULTI;
207}
208
209static void uml_net_tx_timeout(struct net_device *dev)
210{
211	dev->trans_start = jiffies;
212	netif_wake_queue(dev);
213}
214
215static int uml_net_set_mac(struct net_device *dev, void *addr)
216{
217	struct uml_net_private *lp = dev->priv;
218	struct sockaddr *hwaddr = addr;
219
220	spin_lock(&lp->lock);
221	memcpy(dev->dev_addr, hwaddr->sa_data, ETH_ALEN);
222	spin_unlock(&lp->lock);
223
224	return(0);
225}
226
227static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
228{
229	struct uml_net_private *lp = dev->priv;
230	int err = 0;
231
232	spin_lock(&lp->lock);
233
234	new_mtu = (*lp->set_mtu)(new_mtu, &lp->user);
235	if(new_mtu < 0){
236		err = new_mtu;
237		goto out;
238	}
239
240	dev->mtu = new_mtu;
241
242 out:
243	spin_unlock(&lp->lock);
244	return err;
245}
246
247static int uml_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
248{
249	static const struct ethtool_drvinfo info = {
250		.cmd     = ETHTOOL_GDRVINFO,
251		.driver  = DRIVER_NAME,
252		.version = "42",
253	};
254	void *useraddr;
255	u32 ethcmd;
256
257	switch (cmd) {
258	case SIOCETHTOOL:
259		useraddr = ifr->ifr_data;
260		if (copy_from_user(&ethcmd, useraddr, sizeof(ethcmd)))
261			return -EFAULT;
262		switch (ethcmd) {
263		case ETHTOOL_GDRVINFO:
264			if (copy_to_user(useraddr, &info, sizeof(info)))
265				return -EFAULT;
266			return 0;
267		default:
268			return -EOPNOTSUPP;
269		}
270	default:
271		return -EINVAL;
272	}
273}
274
275void uml_net_user_timer_expire(unsigned long _conn)
276{
277#ifdef undef
278	struct connection *conn = (struct connection *)_conn;
279
280	dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
281	do_connect(conn);
282#endif
283}
284
285static DEFINE_SPINLOCK(devices_lock);
286static struct list_head devices = LIST_HEAD_INIT(devices);
287
288static struct device_driver uml_net_driver = {
289	.name  = DRIVER_NAME,
290	.bus   = &platform_bus_type,
291};
292static int driver_registered;
293
294static int eth_configure(int n, void *init, char *mac,
295			 struct transport *transport)
296{
297	struct uml_net *device;
298	struct net_device *dev;
299	struct uml_net_private *lp;
300	int save, err, size;
301
302	size = transport->private_size + sizeof(struct uml_net_private) + 
303		sizeof(((struct uml_net_private *) 0)->user);
304
305	device = kmalloc(sizeof(*device), GFP_KERNEL);
306	if (device == NULL) {
307		printk(KERN_ERR "eth_configure failed to allocate uml_net\n");
308		return(1);
309	}
310
311	memset(device, 0, sizeof(*device));
312	INIT_LIST_HEAD(&device->list);
313	device->index = n;
314
315	spin_lock(&devices_lock);
316	list_add(&device->list, &devices);
317	spin_unlock(&devices_lock);
318
319	if (setup_etheraddr(mac, device->mac))
320		device->have_mac = 1;
321
322	printk(KERN_INFO "Netdevice %d ", n);
323	if (device->have_mac)
324		printk("(%02x:%02x:%02x:%02x:%02x:%02x) ",
325		       device->mac[0], device->mac[1],
326		       device->mac[2], device->mac[3],
327		       device->mac[4], device->mac[5]);
328	printk(": ");
329	dev = alloc_etherdev(size);
330	if (dev == NULL) {
331		printk(KERN_ERR "eth_configure: failed to allocate device\n");
332		return 1;
333	}
334
335	/* sysfs register */
336	if (!driver_registered) {
337		driver_register(&uml_net_driver);
338		driver_registered = 1;
339	}
340	device->pdev.id = n;
341	device->pdev.name = DRIVER_NAME;
342	platform_device_register(&device->pdev);
343	SET_NETDEV_DEV(dev,&device->pdev.dev);
344
345	/* If this name ends up conflicting with an existing registered
346	 * netdevice, that is OK, register_netdev{,ice}() will notice this
347	 * and fail.
348	 */
349	snprintf(dev->name, sizeof(dev->name), "eth%d", n);
350	device->dev = dev;
351
352	(*transport->kern->init)(dev, init);
353
354	dev->mtu = transport->user->max_packet;
355	dev->open = uml_net_open;
356	dev->hard_start_xmit = uml_net_start_xmit;
357	dev->stop = uml_net_close;
358	dev->get_stats = uml_net_get_stats;
359	dev->set_multicast_list = uml_net_set_multicast_list;
360	dev->tx_timeout = uml_net_tx_timeout;
361	dev->set_mac_address = uml_net_set_mac;
362	dev->change_mtu = uml_net_change_mtu;
363	dev->do_ioctl = uml_net_ioctl;
364	dev->watchdog_timeo = (HZ >> 1);
365	dev->irq = UM_ETH_IRQ;
366
367	rtnl_lock();
368	err = register_netdevice(dev);
369	rtnl_unlock();
370	if (err) {
371		device->dev = NULL;
372		/* XXX: should we call ->remove() here? */
373		free_netdev(dev);
374		return 1;
375	}
376	lp = dev->priv;
377
378	/* lp.user is the first four bytes of the transport data, which
379	 * has already been initialized.  This structure assignment will
380	 * overwrite that, so we make sure that .user gets overwritten with
381	 * what it already has.
382	 */
383	save = lp->user[0];
384	*lp = ((struct uml_net_private)
385		{ .list  		= LIST_HEAD_INIT(lp->list),
386		  .dev 			= dev,
387		  .fd 			= -1,
388		  .mac 			= { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
389		  .have_mac 		= device->have_mac,
390		  .protocol 		= transport->kern->protocol,
391		  .open 		= transport->user->open,
392		  .close 		= transport->user->close,
393		  .remove 		= transport->user->remove,
394		  .read 		= transport->kern->read,
395		  .write 		= transport->kern->write,
396		  .add_address 		= transport->user->add_address,
397		  .delete_address  	= transport->user->delete_address,
398		  .set_mtu 		= transport->user->set_mtu,
399		  .user  		= { save } });
400
401	init_timer(&lp->tl);
402	spin_lock_init(&lp->lock);
403	lp->tl.function = uml_net_user_timer_expire;
404	if (lp->have_mac)
405		memcpy(lp->mac, device->mac, sizeof(lp->mac));
406
407	if (transport->user->init) 
408		(*transport->user->init)(&lp->user, dev);
409
410	if (device->have_mac)
411		set_ether_mac(dev, device->mac);
412
413	spin_lock(&opened_lock);
414	list_add(&lp->list, &opened);
415	spin_unlock(&opened_lock);
416
417	return(0);
418}
419
420static struct uml_net *find_device(int n)
421{
422	struct uml_net *device;
423	struct list_head *ele;
424
425	spin_lock(&devices_lock);
426	list_for_each(ele, &devices){
427		device = list_entry(ele, struct uml_net, list);
428		if(device->index == n)
429			goto out;
430	}
431	device = NULL;
432 out:
433	spin_unlock(&devices_lock);
434	return(device);
435}
436
437static int eth_parse(char *str, int *index_out, char **str_out)
438{
439	char *end;
440	int n;
441
442	n = simple_strtoul(str, &end, 0);
443	if(end == str){
444		printk(KERN_ERR "eth_setup: Failed to parse '%s'\n", str);
445		return(1);
446	}
447	if(n < 0){
448		printk(KERN_ERR "eth_setup: device %d is negative\n", n);
449		return(1);
450	}
451	str = end;
452	if(*str != '='){
453		printk(KERN_ERR 
454		       "eth_setup: expected '=' after device number\n");
455		return(1);
456	}
457	str++;
458	if(find_device(n)){
459		printk(KERN_ERR "eth_setup: Device %d already configured\n",
460		       n);
461		return(1);
462	}
463	if(index_out) *index_out = n;
464	*str_out = str;
465	return(0);
466}
467
468struct eth_init {
469	struct list_head list;
470	char *init;
471	int index;
472};
473
474/* Filled in at boot time.  Will need locking if the transports become
475 * modular.
476 */
477struct list_head transports = LIST_HEAD_INIT(transports);
478
479/* Filled in during early boot */
480struct list_head eth_cmd_line = LIST_HEAD_INIT(eth_cmd_line);
481
482static int check_transport(struct transport *transport, char *eth, int n,
483			   void **init_out, char **mac_out)
484{
485	int len;
486
487	len = strlen(transport->name);
488	if(strncmp(eth, transport->name, len))
489		return(0);
490
491	eth += len;
492	if(*eth == ',')
493		eth++;
494	else if(*eth != '\0')
495		return(0);
496
497	*init_out = kmalloc(transport->setup_size, GFP_KERNEL);
498	if(*init_out == NULL)
499		return(1);
500
501	if(!transport->setup(eth, mac_out, *init_out)){
502		kfree(*init_out);
503		*init_out = NULL;
504	}
505	return(1);
506}
507
508void register_transport(struct transport *new)
509{
510	struct list_head *ele, *next;
511	struct eth_init *eth;
512	void *init;
513	char *mac = NULL;
514	int match;
515
516	list_add(&new->list, &transports);
517
518	list_for_each_safe(ele, next, &eth_cmd_line){
519		eth = list_entry(ele, struct eth_init, list);
520		match = check_transport(new, eth->init, eth->index, &init,
521					&mac);
522		if(!match)
523			continue;
524		else if(init != NULL){
525			eth_configure(eth->index, init, mac, new);
526			kfree(init);
527		}
528		list_del(&eth->list);
529	}
530}
531
532static int eth_setup_common(char *str, int index)
533{
534	struct list_head *ele;
535	struct transport *transport;
536	void *init;
537	char *mac = NULL;
538
539	list_for_each(ele, &transports){
540		transport = list_entry(ele, struct transport, list);
541	        if(!check_transport(transport, str, index, &init, &mac))
542			continue;
543		if(init != NULL){
544			eth_configure(index, init, mac, transport);
545			kfree(init);
546		}
547		return(1);
548	}
549	return(0);
550}
551
552static int eth_setup(char *str)
553{
554	struct eth_init *new;
555	int n, err;
556
557	err = eth_parse(str, &n, &str);
558	if(err) return(1);
559
560	new = alloc_bootmem(sizeof(new));
561	if (new == NULL){
562		printk("eth_init : alloc_bootmem failed\n");
563		return(1);
564	}
565
566	INIT_LIST_HEAD(&new->list);
567	new->index = n;
568	new->init = str;
569
570	list_add_tail(&new->list, &eth_cmd_line);
571	return(1);
572}
573
574__setup("eth", eth_setup);
575__uml_help(eth_setup,
576"eth[0-9]+=<transport>,<options>\n"
577"    Configure a network device.\n\n"
578);
579
580#if 0
581static int eth_init(void)
582{
583	struct list_head *ele, *next;
584	struct eth_init *eth;
585
586	list_for_each_safe(ele, next, &eth_cmd_line){
587		eth = list_entry(ele, struct eth_init, list);
588
589		if(eth_setup_common(eth->init, eth->index))
590			list_del(&eth->list);
591	}
592	
593	return(1);
594}
595__initcall(eth_init);
596#endif
597
598static int net_config(char *str)
599{
600	int n, err;
601
602	err = eth_parse(str, &n, &str);
603	if(err) return(err);
604
605	str = uml_strdup(str);
606	if(str == NULL){
607		printk(KERN_ERR "net_config failed to strdup string\n");
608		return(-1);
609	}
610	err = !eth_setup_common(str, n);
611	if(err) 
612		kfree(str);
613	return(err);
614}
615
616static int net_remove(char *str)
617{
618	struct uml_net *device;
619	struct net_device *dev;
620	struct uml_net_private *lp;
621	char *end;
622	int n;
623
624	n = simple_strtoul(str, &end, 0);
625	if((*end != '\0') || (end == str))
626		return(-1);
627
628	device = find_device(n);
629	if(device == NULL)
630		return(0);
631
632	dev = device->dev;
633	lp = dev->priv;
634	if(lp->fd > 0) return(-1);
635	if(lp->remove != NULL) (*lp->remove)(&lp->user);
636	unregister_netdev(dev);
637	platform_device_unregister(&device->pdev);
638
639	list_del(&device->list);
640	kfree(device);
641	free_netdev(dev);
642	return(0);
643}
644
645static struct mc_device net_mc = {
646	.name		= "eth",
647	.config		= net_config,
648	.get_config	= NULL,
649	.remove		= net_remove,
650};
651
652static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
653			      void *ptr)
654{
655	struct in_ifaddr *ifa = ptr;
656	u32 addr = ifa->ifa_address;
657	u32 netmask = ifa->ifa_mask;
658	struct net_device *dev = ifa->ifa_dev->dev;
659	struct uml_net_private *lp;
660	void (*proc)(unsigned char *, unsigned char *, void *);
661	unsigned char addr_buf[4], netmask_buf[4];
662
663	if(dev->open != uml_net_open) return(NOTIFY_DONE);
664
665	lp = dev->priv;
666
667	proc = NULL;
668	switch (event){
669	case NETDEV_UP:
670		proc = lp->add_address;
671		break;
672	case NETDEV_DOWN:
673		proc = lp->delete_address;
674		break;
675	}
676	if(proc != NULL){
677		addr_buf[0] = addr & 0xff;
678		addr_buf[1] = (addr >> 8) & 0xff;
679		addr_buf[2] = (addr >> 16) & 0xff;
680		addr_buf[3] = addr >> 24;
681		netmask_buf[0] = netmask & 0xff;
682		netmask_buf[1] = (netmask >> 8) & 0xff;
683		netmask_buf[2] = (netmask >> 16) & 0xff;
684		netmask_buf[3] = netmask >> 24;
685		(*proc)(addr_buf, netmask_buf, &lp->user);
686	}
687	return(NOTIFY_DONE);
688}
689
690struct notifier_block uml_inetaddr_notifier = {
691	.notifier_call		= uml_inetaddr_event,
692};
693
694static int uml_net_init(void)
695{
696	struct list_head *ele;
697	struct uml_net_private *lp;	
698	struct in_device *ip;
699	struct in_ifaddr *in;
700
701	mconsole_register_dev(&net_mc);
702	register_inetaddr_notifier(&uml_inetaddr_notifier);
703
704	/* Devices may have been opened already, so the uml_inetaddr_notifier
705	 * didn't get a chance to run for them.  This fakes it so that
706	 * addresses which have already been set up get handled properly.
707	 */
708	list_for_each(ele, &opened){
709		lp = list_entry(ele, struct uml_net_private, list);
710		ip = lp->dev->ip_ptr;
711		if(ip == NULL) continue;
712		in = ip->ifa_list;
713		while(in != NULL){
714			uml_inetaddr_event(NULL, NETDEV_UP, in);
715			in = in->ifa_next;
716		}
717	}	
718
719	return(0);
720}
721
722__initcall(uml_net_init);
723
724static void close_devices(void)
725{
726	struct list_head *ele;
727	struct uml_net_private *lp;
728
729	list_for_each(ele, &opened){
730		lp = list_entry(ele, struct uml_net_private, list);
731		if((lp->close != NULL) && (lp->fd >= 0))
732			(*lp->close)(lp->fd, &lp->user);
733		if(lp->remove != NULL) (*lp->remove)(&lp->user);
734	}
735}
736
737__uml_exitcall(close_devices);
738
739int setup_etheraddr(char *str, unsigned char *addr)
740{
741	char *end;
742	int i;
743
744	if(str == NULL)
745		return(0);
746	for(i=0;i<6;i++){
747		addr[i] = simple_strtoul(str, &end, 16);
748		if((end == str) ||
749		   ((*end != ':') && (*end != ',') && (*end != '\0'))){
750			printk(KERN_ERR 
751			       "setup_etheraddr: failed to parse '%s' "
752			       "as an ethernet address\n", str);
753			return(0);
754		}
755		str = end + 1;
756	}
757	if(addr[0] & 1){
758		printk(KERN_ERR 
759		       "Attempt to assign a broadcast ethernet address to a "
760		       "device disallowed\n");
761		return(0);
762	}
763	return(1);
764}
765
766void dev_ip_addr(void *d, char *buf, char *bin_buf)
767{
768	struct net_device *dev = d;
769	struct in_device *ip = dev->ip_ptr;
770	struct in_ifaddr *in;
771	u32 addr;
772
773	if((ip == NULL) || ((in = ip->ifa_list) == NULL)){
774		printk(KERN_WARNING "dev_ip_addr - device not assigned an "
775		       "IP address\n");
776		return;
777	}
778	addr = in->ifa_address;
779	sprintf(buf, "%d.%d.%d.%d", addr & 0xff, (addr >> 8) & 0xff, 
780		(addr >> 16) & 0xff, addr >> 24);
781	if(bin_buf){
782		bin_buf[0] = addr & 0xff;
783		bin_buf[1] = (addr >> 8) & 0xff;
784		bin_buf[2] = (addr >> 16) & 0xff;
785		bin_buf[3] = addr >> 24;
786	}
787}
788
789void set_ether_mac(void *d, unsigned char *addr)
790{
791	struct net_device *dev = d;
792
793	memcpy(dev->dev_addr, addr, ETH_ALEN);	
794}
795
796struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra)
797{
798	if((skb != NULL) && (skb_tailroom(skb) < extra)){
799	  	struct sk_buff *skb2;
800
801		skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC);
802		dev_kfree_skb(skb);
803		skb = skb2;
804	}
805	if(skb != NULL) skb_put(skb, extra);
806	return(skb);
807}
808
809void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *, 
810					void *), 
811		    void *arg)
812{
813	struct net_device *dev = d;
814	struct in_device *ip = dev->ip_ptr;
815	struct in_ifaddr *in;
816	unsigned char address[4], netmask[4];
817
818	if(ip == NULL) return;
819	in = ip->ifa_list;
820	while(in != NULL){
821		address[0] = in->ifa_address & 0xff;
822		address[1] = (in->ifa_address >> 8) & 0xff;
823		address[2] = (in->ifa_address >> 16) & 0xff;
824		address[3] = in->ifa_address >> 24;
825		netmask[0] = in->ifa_mask & 0xff;
826		netmask[1] = (in->ifa_mask >> 8) & 0xff;
827		netmask[2] = (in->ifa_mask >> 16) & 0xff;
828		netmask[3] = in->ifa_mask >> 24;
829		(*cb)(address, netmask, arg);
830		in = in->ifa_next;
831	}
832}
833
834int dev_netmask(void *d, void *m)
835{
836	struct net_device *dev = d;
837	struct in_device *ip = dev->ip_ptr;
838	struct in_ifaddr *in;
839	__u32 *mask_out = m;
840
841	if(ip == NULL) 
842		return(1);
843
844	in = ip->ifa_list;
845	if(in == NULL) 
846		return(1);
847
848	*mask_out = in->ifa_mask;
849	return(0);
850}
851
852void *get_output_buffer(int *len_out)
853{
854	void *ret;
855
856	ret = (void *) __get_free_pages(GFP_KERNEL, 0);
857	if(ret) *len_out = PAGE_SIZE;
858	else *len_out = 0;
859	return(ret);
860}
861
862void free_output_buffer(void *buffer)
863{
864	free_pages((unsigned long) buffer, 0);
865}
866
867int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out, 
868		     char **gate_addr)
869{
870	char *remain;
871
872	remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
873	if(remain != NULL){
874		printk("tap_setup_common - Extra garbage on specification : "
875		       "'%s'\n", remain);
876		return(1);
877	}
878
879	return(0);
880}
881
882unsigned short eth_protocol(struct sk_buff *skb)
883{
884	return(eth_type_trans(skb, skb->dev));
885}
886
887/*
888 * Overrides for Emacs so that we follow Linus's tabbing style.
889 * Emacs will notice this stuff at the end of the file and automatically
890 * adjust the settings for this buffer only.  This must remain at the end
891 * of the file.
892 * ---------------------------------------------------------------------------
893 * Local variables:
894 * c-file-style: "linux"
895 * End:
896 */