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v3.5.6
  1/*
  2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  3 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
  4 * James Leu (jleu@mindspring.net).
  5 * Copyright (C) 2001 by various other people who didn't put their name here.
  6 * Licensed under the GPL.
  7 */
  8
  9#include <linux/bootmem.h>
 10#include <linux/etherdevice.h>
 11#include <linux/ethtool.h>
 12#include <linux/inetdevice.h>
 13#include <linux/init.h>
 14#include <linux/list.h>
 15#include <linux/netdevice.h>
 16#include <linux/platform_device.h>
 17#include <linux/rtnetlink.h>
 18#include <linux/skbuff.h>
 19#include <linux/slab.h>
 20#include <linux/spinlock.h>
 21#include "init.h"
 22#include "irq_kern.h"
 23#include "irq_user.h"
 24#include "mconsole_kern.h"
 25#include "net_kern.h"
 26#include "net_user.h"
 27
 28#define DRIVER_NAME "uml-netdev"
 29
 30static DEFINE_SPINLOCK(opened_lock);
 31static LIST_HEAD(opened);
 32
 33/*
 34 * The drop_skb is used when we can't allocate an skb.  The
 35 * packet is read into drop_skb in order to get the data off the
 36 * connection to the host.
 37 * It is reallocated whenever a maximum packet size is seen which is
 38 * larger than any seen before.  update_drop_skb is called from
 39 * eth_configure when a new interface is added.
 40 */
 41static DEFINE_SPINLOCK(drop_lock);
 42static struct sk_buff *drop_skb;
 43static int drop_max;
 44
 45static int update_drop_skb(int max)
 46{
 47	struct sk_buff *new;
 48	unsigned long flags;
 49	int err = 0;
 50
 51	spin_lock_irqsave(&drop_lock, flags);
 52
 53	if (max <= drop_max)
 54		goto out;
 55
 56	err = -ENOMEM;
 57	new = dev_alloc_skb(max);
 58	if (new == NULL)
 59		goto out;
 60
 61	skb_put(new, max);
 62
 63	kfree_skb(drop_skb);
 64	drop_skb = new;
 65	drop_max = max;
 66	err = 0;
 67out:
 68	spin_unlock_irqrestore(&drop_lock, flags);
 69
 70	return err;
 71}
 72
 73static int uml_net_rx(struct net_device *dev)
 74{
 75	struct uml_net_private *lp = netdev_priv(dev);
 76	int pkt_len;
 77	struct sk_buff *skb;
 78
 79	/* If we can't allocate memory, try again next round. */
 80	skb = dev_alloc_skb(lp->max_packet);
 81	if (skb == NULL) {
 82		drop_skb->dev = dev;
 83		/* Read a packet into drop_skb and don't do anything with it. */
 84		(*lp->read)(lp->fd, drop_skb, lp);
 85		dev->stats.rx_dropped++;
 86		return 0;
 87	}
 88
 89	skb->dev = dev;
 90	skb_put(skb, lp->max_packet);
 91	skb_reset_mac_header(skb);
 92	pkt_len = (*lp->read)(lp->fd, skb, lp);
 93
 94	if (pkt_len > 0) {
 95		skb_trim(skb, pkt_len);
 96		skb->protocol = (*lp->protocol)(skb);
 97
 98		dev->stats.rx_bytes += skb->len;
 99		dev->stats.rx_packets++;
100		netif_rx(skb);
101		return pkt_len;
102	}
103
104	kfree_skb(skb);
105	return pkt_len;
106}
107
108static void uml_dev_close(struct work_struct *work)
109{
110	struct uml_net_private *lp =
111		container_of(work, struct uml_net_private, work);
112	dev_close(lp->dev);
113}
114
115static irqreturn_t uml_net_interrupt(int irq, void *dev_id)
116{
117	struct net_device *dev = dev_id;
118	struct uml_net_private *lp = netdev_priv(dev);
119	int err;
120
121	if (!netif_running(dev))
122		return IRQ_NONE;
123
124	spin_lock(&lp->lock);
125	while ((err = uml_net_rx(dev)) > 0) ;
126	if (err < 0) {
127		printk(KERN_ERR
128		       "Device '%s' read returned %d, shutting it down\n",
129		       dev->name, err);
130		/* dev_close can't be called in interrupt context, and takes
131		 * again lp->lock.
132		 * And dev_close() can be safely called multiple times on the
133		 * same device, since it tests for (dev->flags & IFF_UP). So
134		 * there's no harm in delaying the device shutdown.
135		 * Furthermore, the workqueue will not re-enqueue an already
136		 * enqueued work item. */
137		schedule_work(&lp->work);
138		goto out;
139	}
140	reactivate_fd(lp->fd, UM_ETH_IRQ);
141
142out:
143	spin_unlock(&lp->lock);
144	return IRQ_HANDLED;
145}
146
147static int uml_net_open(struct net_device *dev)
148{
149	struct uml_net_private *lp = netdev_priv(dev);
150	int err;
151
152	if (lp->fd >= 0) {
153		err = -ENXIO;
154		goto out;
155	}
156
157	lp->fd = (*lp->open)(&lp->user);
158	if (lp->fd < 0) {
159		err = lp->fd;
160		goto out;
161	}
162
163	err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
164			     IRQF_SHARED, dev->name, dev);
165	if (err != 0) {
166		printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
167		err = -ENETUNREACH;
168		goto out_close;
169	}
170
171	lp->tl.data = (unsigned long) &lp->user;
172	netif_start_queue(dev);
173
174	/* clear buffer - it can happen that the host side of the interface
175	 * is full when we get here.  In this case, new data is never queued,
176	 * SIGIOs never arrive, and the net never works.
177	 */
178	while ((err = uml_net_rx(dev)) > 0) ;
179
180	spin_lock(&opened_lock);
181	list_add(&lp->list, &opened);
182	spin_unlock(&opened_lock);
183
184	return 0;
185out_close:
186	if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
187	lp->fd = -1;
188out:
189	return err;
190}
191
192static int uml_net_close(struct net_device *dev)
193{
194	struct uml_net_private *lp = netdev_priv(dev);
195
196	netif_stop_queue(dev);
197
198	um_free_irq(dev->irq, dev);
199	if (lp->close != NULL)
200		(*lp->close)(lp->fd, &lp->user);
201	lp->fd = -1;
202
203	spin_lock(&opened_lock);
204	list_del(&lp->list);
205	spin_unlock(&opened_lock);
206
207	return 0;
208}
209
210static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
211{
212	struct uml_net_private *lp = netdev_priv(dev);
213	unsigned long flags;
214	int len;
215
216	netif_stop_queue(dev);
217
218	spin_lock_irqsave(&lp->lock, flags);
219
220	len = (*lp->write)(lp->fd, skb, lp);
 
221
222	if (len == skb->len) {
223		dev->stats.tx_packets++;
224		dev->stats.tx_bytes += skb->len;
225		dev->trans_start = jiffies;
226		netif_start_queue(dev);
227
228		/* this is normally done in the interrupt when tx finishes */
229		netif_wake_queue(dev);
230	}
231	else if (len == 0) {
232		netif_start_queue(dev);
233		dev->stats.tx_dropped++;
234	}
235	else {
236		netif_start_queue(dev);
237		printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
238	}
239
240	spin_unlock_irqrestore(&lp->lock, flags);
241
242	dev_kfree_skb(skb);
243
244	return NETDEV_TX_OK;
245}
246
247static void uml_net_set_multicast_list(struct net_device *dev)
248{
249	return;
250}
251
252static void uml_net_tx_timeout(struct net_device *dev)
253{
254	dev->trans_start = jiffies;
255	netif_wake_queue(dev);
256}
257
258static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
259{
260	dev->mtu = new_mtu;
261
262	return 0;
263}
264
265#ifdef CONFIG_NET_POLL_CONTROLLER
266static void uml_net_poll_controller(struct net_device *dev)
267{
268	disable_irq(dev->irq);
269	uml_net_interrupt(dev->irq, dev);
270	enable_irq(dev->irq);
271}
272#endif
273
274static void uml_net_get_drvinfo(struct net_device *dev,
275				struct ethtool_drvinfo *info)
276{
277	strcpy(info->driver, DRIVER_NAME);
278	strcpy(info->version, "42");
279}
280
281static const struct ethtool_ops uml_net_ethtool_ops = {
282	.get_drvinfo	= uml_net_get_drvinfo,
283	.get_link	= ethtool_op_get_link,
 
284};
285
286static void uml_net_user_timer_expire(unsigned long _conn)
287{
288#ifdef undef
289	struct connection *conn = (struct connection *)_conn;
 
290
291	dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
292	do_connect(conn);
293#endif
294}
295
296static int setup_etheraddr(char *str, unsigned char *addr, char *name)
297{
 
298	char *end;
299	int i;
300
301	if (str == NULL)
302		goto random;
303
304	for (i = 0; i < 6; i++) {
305		addr[i] = simple_strtoul(str, &end, 16);
306		if ((end == str) ||
307		   ((*end != ':') && (*end != ',') && (*end != '\0'))) {
308			printk(KERN_ERR
309			       "setup_etheraddr: failed to parse '%s' "
310			       "as an ethernet address\n", str);
311			goto random;
312		}
313		str = end + 1;
314	}
315	if (is_multicast_ether_addr(addr)) {
316		printk(KERN_ERR
317		       "Attempt to assign a multicast ethernet address to a "
318		       "device disallowed\n");
319		goto random;
320	}
321	if (!is_valid_ether_addr(addr)) {
322		printk(KERN_ERR
323		       "Attempt to assign an invalid ethernet address to a "
324		       "device disallowed\n");
325		goto random;
326	}
327	if (!is_local_ether_addr(addr)) {
328		printk(KERN_WARNING
329		       "Warning: Assigning a globally valid ethernet "
330		       "address to a device\n");
331		printk(KERN_WARNING "You should set the 2nd rightmost bit in "
332		       "the first byte of the MAC,\n");
333		printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n",
334		       addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4],
335		       addr[5]);
336	}
337	return 0;
338
339random:
340	printk(KERN_INFO
341	       "Choosing a random ethernet address for device %s\n", name);
342	random_ether_addr(addr);
343	return 1;
344}
345
346static DEFINE_SPINLOCK(devices_lock);
347static LIST_HEAD(devices);
348
349static struct platform_driver uml_net_driver = {
350	.driver = {
351		.name  = DRIVER_NAME,
352	},
353};
354
355static void net_device_release(struct device *dev)
356{
357	struct uml_net *device = dev_get_drvdata(dev);
358	struct net_device *netdev = device->dev;
359	struct uml_net_private *lp = netdev_priv(netdev);
360
361	if (lp->remove != NULL)
362		(*lp->remove)(&lp->user);
363	list_del(&device->list);
364	kfree(device);
365	free_netdev(netdev);
366}
367
368static const struct net_device_ops uml_netdev_ops = {
369	.ndo_open 		= uml_net_open,
370	.ndo_stop 		= uml_net_close,
371	.ndo_start_xmit 	= uml_net_start_xmit,
372	.ndo_set_rx_mode	= uml_net_set_multicast_list,
373	.ndo_tx_timeout 	= uml_net_tx_timeout,
374	.ndo_set_mac_address	= eth_mac_addr,
375	.ndo_change_mtu 	= uml_net_change_mtu,
376	.ndo_validate_addr	= eth_validate_addr,
377#ifdef CONFIG_NET_POLL_CONTROLLER
378	.ndo_poll_controller = uml_net_poll_controller,
379#endif
380};
381
382/*
383 * Ensures that platform_driver_register is called only once by
384 * eth_configure.  Will be set in an initcall.
385 */
386static int driver_registered;
387
388static void eth_configure(int n, void *init, char *mac,
389			  struct transport *transport)
390{
391	struct uml_net *device;
392	struct net_device *dev;
393	struct uml_net_private *lp;
394	int err, size;
395	int random_mac;
396
397	size = transport->private_size + sizeof(struct uml_net_private);
398
399	device = kzalloc(sizeof(*device), GFP_KERNEL);
400	if (device == NULL) {
401		printk(KERN_ERR "eth_configure failed to allocate struct "
402		       "uml_net\n");
403		return;
404	}
405
406	dev = alloc_etherdev(size);
407	if (dev == NULL) {
408		printk(KERN_ERR "eth_configure: failed to allocate struct "
409		       "net_device for eth%d\n", n);
410		goto out_free_device;
411	}
412
413	INIT_LIST_HEAD(&device->list);
414	device->index = n;
415
416	/* If this name ends up conflicting with an existing registered
417	 * netdevice, that is OK, register_netdev{,ice}() will notice this
418	 * and fail.
419	 */
420	snprintf(dev->name, sizeof(dev->name), "eth%d", n);
421
422	random_mac = setup_etheraddr(mac, device->mac, dev->name);
423
424	printk(KERN_INFO "Netdevice %d (%pM) : ", n, device->mac);
425
426	lp = netdev_priv(dev);
427	/* This points to the transport private data. It's still clear, but we
428	 * must memset it to 0 *now*. Let's help the drivers. */
429	memset(lp, 0, size);
430	INIT_WORK(&lp->work, uml_dev_close);
431
432	/* sysfs register */
433	if (!driver_registered) {
434		platform_driver_register(&uml_net_driver);
435		driver_registered = 1;
436	}
437	device->pdev.id = n;
438	device->pdev.name = DRIVER_NAME;
439	device->pdev.dev.release = net_device_release;
440	dev_set_drvdata(&device->pdev.dev, device);
441	if (platform_device_register(&device->pdev))
442		goto out_free_netdev;
443	SET_NETDEV_DEV(dev,&device->pdev.dev);
444
445	device->dev = dev;
446
447	/*
448	 * These just fill in a data structure, so there's no failure
449	 * to be worried about.
450	 */
451	(*transport->kern->init)(dev, init);
452
453	*lp = ((struct uml_net_private)
454		{ .list  		= LIST_HEAD_INIT(lp->list),
455		  .dev 			= dev,
456		  .fd 			= -1,
457		  .mac 			= { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
458		  .max_packet		= transport->user->max_packet,
459		  .protocol 		= transport->kern->protocol,
460		  .open 		= transport->user->open,
461		  .close 		= transport->user->close,
462		  .remove 		= transport->user->remove,
463		  .read 		= transport->kern->read,
464		  .write 		= transport->kern->write,
465		  .add_address 		= transport->user->add_address,
466		  .delete_address  	= transport->user->delete_address });
467
468	init_timer(&lp->tl);
469	spin_lock_init(&lp->lock);
470	lp->tl.function = uml_net_user_timer_expire;
471	memcpy(lp->mac, device->mac, sizeof(lp->mac));
472
473	if ((transport->user->init != NULL) &&
474	    ((*transport->user->init)(&lp->user, dev) != 0))
475		goto out_unregister;
476
477	/* don't use eth_mac_addr, it will not work here */
478	memcpy(dev->dev_addr, device->mac, ETH_ALEN);
479	if (random_mac)
480		dev->addr_assign_type |= NET_ADDR_RANDOM;
481
482	dev->mtu = transport->user->mtu;
483	dev->netdev_ops = &uml_netdev_ops;
484	dev->ethtool_ops = &uml_net_ethtool_ops;
485	dev->watchdog_timeo = (HZ >> 1);
486	dev->irq = UM_ETH_IRQ;
487
488	err = update_drop_skb(lp->max_packet);
489	if (err)
490		goto out_undo_user_init;
491
492	rtnl_lock();
493	err = register_netdevice(dev);
494	rtnl_unlock();
495	if (err)
496		goto out_undo_user_init;
497
498	spin_lock(&devices_lock);
499	list_add(&device->list, &devices);
500	spin_unlock(&devices_lock);
501
502	return;
503
504out_undo_user_init:
505	if (transport->user->remove != NULL)
506		(*transport->user->remove)(&lp->user);
507out_unregister:
508	platform_device_unregister(&device->pdev);
509	return; /* platform_device_unregister frees dev and device */
510out_free_netdev:
511	free_netdev(dev);
512out_free_device:
513	kfree(device);
514}
515
516static struct uml_net *find_device(int n)
517{
518	struct uml_net *device;
519	struct list_head *ele;
520
521	spin_lock(&devices_lock);
522	list_for_each(ele, &devices) {
523		device = list_entry(ele, struct uml_net, list);
524		if (device->index == n)
525			goto out;
526	}
527	device = NULL;
528 out:
529	spin_unlock(&devices_lock);
530	return device;
531}
532
533static int eth_parse(char *str, int *index_out, char **str_out,
534		     char **error_out)
535{
536	char *end;
537	int n, err = -EINVAL;
538
539	n = simple_strtoul(str, &end, 0);
540	if (end == str) {
541		*error_out = "Bad device number";
542		return err;
543	}
544
545	str = end;
546	if (*str != '=') {
547		*error_out = "Expected '=' after device number";
548		return err;
549	}
550
551	str++;
552	if (find_device(n)) {
553		*error_out = "Device already configured";
554		return err;
555	}
556
557	*index_out = n;
558	*str_out = str;
559	return 0;
560}
561
562struct eth_init {
563	struct list_head list;
564	char *init;
565	int index;
566};
567
568static DEFINE_SPINLOCK(transports_lock);
569static LIST_HEAD(transports);
570
571/* Filled in during early boot */
572static LIST_HEAD(eth_cmd_line);
573
574static int check_transport(struct transport *transport, char *eth, int n,
575			   void **init_out, char **mac_out)
576{
577	int len;
578
579	len = strlen(transport->name);
580	if (strncmp(eth, transport->name, len))
581		return 0;
582
583	eth += len;
584	if (*eth == ',')
585		eth++;
586	else if (*eth != '\0')
587		return 0;
588
589	*init_out = kmalloc(transport->setup_size, GFP_KERNEL);
590	if (*init_out == NULL)
591		return 1;
592
593	if (!transport->setup(eth, mac_out, *init_out)) {
594		kfree(*init_out);
595		*init_out = NULL;
596	}
597	return 1;
598}
599
600void register_transport(struct transport *new)
601{
602	struct list_head *ele, *next;
603	struct eth_init *eth;
604	void *init;
605	char *mac = NULL;
606	int match;
607
608	spin_lock(&transports_lock);
609	BUG_ON(!list_empty(&new->list));
610	list_add(&new->list, &transports);
611	spin_unlock(&transports_lock);
612
613	list_for_each_safe(ele, next, &eth_cmd_line) {
614		eth = list_entry(ele, struct eth_init, list);
615		match = check_transport(new, eth->init, eth->index, &init,
616					&mac);
617		if (!match)
618			continue;
619		else if (init != NULL) {
620			eth_configure(eth->index, init, mac, new);
621			kfree(init);
622		}
623		list_del(&eth->list);
624	}
625}
626
627static int eth_setup_common(char *str, int index)
628{
629	struct list_head *ele;
630	struct transport *transport;
631	void *init;
632	char *mac = NULL;
633	int found = 0;
634
635	spin_lock(&transports_lock);
636	list_for_each(ele, &transports) {
637		transport = list_entry(ele, struct transport, list);
638	        if (!check_transport(transport, str, index, &init, &mac))
 
639			continue;
640		if (init != NULL) {
641			eth_configure(index, init, mac, transport);
642			kfree(init);
643		}
644		found = 1;
645		break;
646	}
647
648	spin_unlock(&transports_lock);
649	return found;
650}
651
652static int __init eth_setup(char *str)
653{
654	struct eth_init *new;
655	char *error;
656	int n, err;
657
658	err = eth_parse(str, &n, &str, &error);
659	if (err) {
660		printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
661		       str, error);
662		return 1;
663	}
664
665	new = alloc_bootmem(sizeof(*new));
666	if (new == NULL) {
667		printk(KERN_ERR "eth_init : alloc_bootmem failed\n");
668		return 1;
669	}
670
671	INIT_LIST_HEAD(&new->list);
672	new->index = n;
673	new->init = str;
674
675	list_add_tail(&new->list, &eth_cmd_line);
676	return 1;
677}
678
679__setup("eth", eth_setup);
680__uml_help(eth_setup,
681"eth[0-9]+=<transport>,<options>\n"
682"    Configure a network device.\n\n"
683);
684
685static int net_config(char *str, char **error_out)
686{
687	int n, err;
688
689	err = eth_parse(str, &n, &str, error_out);
690	if (err)
691		return err;
692
693	/* This string is broken up and the pieces used by the underlying
694	 * driver.  So, it is freed only if eth_setup_common fails.
695	 */
696	str = kstrdup(str, GFP_KERNEL);
697	if (str == NULL) {
698	        *error_out = "net_config failed to strdup string";
699		return -ENOMEM;
700	}
701	err = !eth_setup_common(str, n);
702	if (err)
703		kfree(str);
704	return err;
705}
706
707static int net_id(char **str, int *start_out, int *end_out)
708{
709	char *end;
710	int n;
711
712	n = simple_strtoul(*str, &end, 0);
713	if ((*end != '\0') || (end == *str))
714		return -1;
715
716	*start_out = n;
717	*end_out = n;
718	*str = end;
719	return n;
720}
721
722static int net_remove(int n, char **error_out)
723{
724	struct uml_net *device;
725	struct net_device *dev;
726	struct uml_net_private *lp;
727
728	device = find_device(n);
729	if (device == NULL)
730		return -ENODEV;
731
732	dev = device->dev;
733	lp = netdev_priv(dev);
734	if (lp->fd > 0)
735		return -EBUSY;
736	unregister_netdev(dev);
737	platform_device_unregister(&device->pdev);
738
739	return 0;
740}
741
742static struct mc_device net_mc = {
743	.list		= LIST_HEAD_INIT(net_mc.list),
744	.name		= "eth",
745	.config		= net_config,
746	.get_config	= NULL,
747	.id		= net_id,
748	.remove		= net_remove,
749};
750
751#ifdef CONFIG_INET
752static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
753			      void *ptr)
754{
755	struct in_ifaddr *ifa = ptr;
756	struct net_device *dev = ifa->ifa_dev->dev;
757	struct uml_net_private *lp;
758	void (*proc)(unsigned char *, unsigned char *, void *);
759	unsigned char addr_buf[4], netmask_buf[4];
760
761	if (dev->netdev_ops->ndo_open != uml_net_open)
762		return NOTIFY_DONE;
763
764	lp = netdev_priv(dev);
765
766	proc = NULL;
767	switch (event) {
768	case NETDEV_UP:
769		proc = lp->add_address;
770		break;
771	case NETDEV_DOWN:
772		proc = lp->delete_address;
773		break;
774	}
775	if (proc != NULL) {
776		memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
777		memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
778		(*proc)(addr_buf, netmask_buf, &lp->user);
779	}
780	return NOTIFY_DONE;
781}
782
783/* uml_net_init shouldn't be called twice on two CPUs at the same time */
784static struct notifier_block uml_inetaddr_notifier = {
785	.notifier_call		= uml_inetaddr_event,
786};
787
788static void inet_register(void)
789{
790	struct list_head *ele;
791	struct uml_net_private *lp;
792	struct in_device *ip;
793	struct in_ifaddr *in;
794
795	register_inetaddr_notifier(&uml_inetaddr_notifier);
796
797	/* Devices may have been opened already, so the uml_inetaddr_notifier
798	 * didn't get a chance to run for them.  This fakes it so that
799	 * addresses which have already been set up get handled properly.
800	 */
801	spin_lock(&opened_lock);
802	list_for_each(ele, &opened) {
803		lp = list_entry(ele, struct uml_net_private, list);
804		ip = lp->dev->ip_ptr;
805		if (ip == NULL)
806			continue;
807		in = ip->ifa_list;
808		while (in != NULL) {
809			uml_inetaddr_event(NULL, NETDEV_UP, in);
810			in = in->ifa_next;
811		}
812	}
813	spin_unlock(&opened_lock);
814}
815#else
816static inline void inet_register(void)
817{
818}
819#endif
820
821static int uml_net_init(void)
822{
823	mconsole_register_dev(&net_mc);
824	inet_register();
825	return 0;
826}
827
828__initcall(uml_net_init);
829
830static void close_devices(void)
831{
832	struct list_head *ele;
833	struct uml_net_private *lp;
834
835	spin_lock(&opened_lock);
836	list_for_each(ele, &opened) {
837		lp = list_entry(ele, struct uml_net_private, list);
838		um_free_irq(lp->dev->irq, lp->dev);
839		if ((lp->close != NULL) && (lp->fd >= 0))
840			(*lp->close)(lp->fd, &lp->user);
841		if (lp->remove != NULL)
842			(*lp->remove)(&lp->user);
843	}
844	spin_unlock(&opened_lock);
845}
846
847__uml_exitcall(close_devices);
848
849void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
850					void *),
851		    void *arg)
852{
853	struct net_device *dev = d;
854	struct in_device *ip = dev->ip_ptr;
855	struct in_ifaddr *in;
856	unsigned char address[4], netmask[4];
857
858	if (ip == NULL) return;
859	in = ip->ifa_list;
860	while (in != NULL) {
861		memcpy(address, &in->ifa_address, sizeof(address));
862		memcpy(netmask, &in->ifa_mask, sizeof(netmask));
863		(*cb)(address, netmask, arg);
864		in = in->ifa_next;
865	}
866}
867
868int dev_netmask(void *d, void *m)
869{
870	struct net_device *dev = d;
871	struct in_device *ip = dev->ip_ptr;
872	struct in_ifaddr *in;
873	__be32 *mask_out = m;
874
875	if (ip == NULL)
876		return 1;
877
878	in = ip->ifa_list;
879	if (in == NULL)
880		return 1;
881
882	*mask_out = in->ifa_mask;
883	return 0;
884}
885
886void *get_output_buffer(int *len_out)
887{
888	void *ret;
889
890	ret = (void *) __get_free_pages(GFP_KERNEL, 0);
891	if (ret) *len_out = PAGE_SIZE;
892	else *len_out = 0;
893	return ret;
894}
895
896void free_output_buffer(void *buffer)
897{
898	free_pages((unsigned long) buffer, 0);
899}
900
901int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
902		     char **gate_addr)
903{
904	char *remain;
905
906	remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
907	if (remain != NULL) {
908		printk(KERN_ERR "tap_setup_common - Extra garbage on "
909		       "specification : '%s'\n", remain);
910		return 1;
911	}
912
913	return 0;
914}
915
916unsigned short eth_protocol(struct sk_buff *skb)
917{
918	return eth_type_trans(skb, skb->dev);
919}
v4.17
  1/*
  2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  3 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
  4 * James Leu (jleu@mindspring.net).
  5 * Copyright (C) 2001 by various other people who didn't put their name here.
  6 * Licensed under the GPL.
  7 */
  8
  9#include <linux/bootmem.h>
 10#include <linux/etherdevice.h>
 11#include <linux/ethtool.h>
 12#include <linux/inetdevice.h>
 13#include <linux/init.h>
 14#include <linux/list.h>
 15#include <linux/netdevice.h>
 16#include <linux/platform_device.h>
 17#include <linux/rtnetlink.h>
 18#include <linux/skbuff.h>
 19#include <linux/slab.h>
 20#include <linux/spinlock.h>
 21#include <init.h>
 22#include <irq_kern.h>
 23#include <irq_user.h>
 24#include "mconsole_kern.h"
 25#include <net_kern.h>
 26#include <net_user.h>
 27
 28#define DRIVER_NAME "uml-netdev"
 29
 30static DEFINE_SPINLOCK(opened_lock);
 31static LIST_HEAD(opened);
 32
 33/*
 34 * The drop_skb is used when we can't allocate an skb.  The
 35 * packet is read into drop_skb in order to get the data off the
 36 * connection to the host.
 37 * It is reallocated whenever a maximum packet size is seen which is
 38 * larger than any seen before.  update_drop_skb is called from
 39 * eth_configure when a new interface is added.
 40 */
 41static DEFINE_SPINLOCK(drop_lock);
 42static struct sk_buff *drop_skb;
 43static int drop_max;
 44
 45static int update_drop_skb(int max)
 46{
 47	struct sk_buff *new;
 48	unsigned long flags;
 49	int err = 0;
 50
 51	spin_lock_irqsave(&drop_lock, flags);
 52
 53	if (max <= drop_max)
 54		goto out;
 55
 56	err = -ENOMEM;
 57	new = dev_alloc_skb(max);
 58	if (new == NULL)
 59		goto out;
 60
 61	skb_put(new, max);
 62
 63	kfree_skb(drop_skb);
 64	drop_skb = new;
 65	drop_max = max;
 66	err = 0;
 67out:
 68	spin_unlock_irqrestore(&drop_lock, flags);
 69
 70	return err;
 71}
 72
 73static int uml_net_rx(struct net_device *dev)
 74{
 75	struct uml_net_private *lp = netdev_priv(dev);
 76	int pkt_len;
 77	struct sk_buff *skb;
 78
 79	/* If we can't allocate memory, try again next round. */
 80	skb = dev_alloc_skb(lp->max_packet);
 81	if (skb == NULL) {
 82		drop_skb->dev = dev;
 83		/* Read a packet into drop_skb and don't do anything with it. */
 84		(*lp->read)(lp->fd, drop_skb, lp);
 85		dev->stats.rx_dropped++;
 86		return 0;
 87	}
 88
 89	skb->dev = dev;
 90	skb_put(skb, lp->max_packet);
 91	skb_reset_mac_header(skb);
 92	pkt_len = (*lp->read)(lp->fd, skb, lp);
 93
 94	if (pkt_len > 0) {
 95		skb_trim(skb, pkt_len);
 96		skb->protocol = (*lp->protocol)(skb);
 97
 98		dev->stats.rx_bytes += skb->len;
 99		dev->stats.rx_packets++;
100		netif_rx(skb);
101		return pkt_len;
102	}
103
104	kfree_skb(skb);
105	return pkt_len;
106}
107
108static void uml_dev_close(struct work_struct *work)
109{
110	struct uml_net_private *lp =
111		container_of(work, struct uml_net_private, work);
112	dev_close(lp->dev);
113}
114
115static irqreturn_t uml_net_interrupt(int irq, void *dev_id)
116{
117	struct net_device *dev = dev_id;
118	struct uml_net_private *lp = netdev_priv(dev);
119	int err;
120
121	if (!netif_running(dev))
122		return IRQ_NONE;
123
124	spin_lock(&lp->lock);
125	while ((err = uml_net_rx(dev)) > 0) ;
126	if (err < 0) {
127		printk(KERN_ERR
128		       "Device '%s' read returned %d, shutting it down\n",
129		       dev->name, err);
130		/* dev_close can't be called in interrupt context, and takes
131		 * again lp->lock.
132		 * And dev_close() can be safely called multiple times on the
133		 * same device, since it tests for (dev->flags & IFF_UP). So
134		 * there's no harm in delaying the device shutdown.
135		 * Furthermore, the workqueue will not re-enqueue an already
136		 * enqueued work item. */
137		schedule_work(&lp->work);
138		goto out;
139	}
140	reactivate_fd(lp->fd, UM_ETH_IRQ);
141
142out:
143	spin_unlock(&lp->lock);
144	return IRQ_HANDLED;
145}
146
147static int uml_net_open(struct net_device *dev)
148{
149	struct uml_net_private *lp = netdev_priv(dev);
150	int err;
151
152	if (lp->fd >= 0) {
153		err = -ENXIO;
154		goto out;
155	}
156
157	lp->fd = (*lp->open)(&lp->user);
158	if (lp->fd < 0) {
159		err = lp->fd;
160		goto out;
161	}
162
163	err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
164			     IRQF_SHARED, dev->name, dev);
165	if (err != 0) {
166		printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
167		err = -ENETUNREACH;
168		goto out_close;
169	}
170
 
171	netif_start_queue(dev);
172
173	/* clear buffer - it can happen that the host side of the interface
174	 * is full when we get here.  In this case, new data is never queued,
175	 * SIGIOs never arrive, and the net never works.
176	 */
177	while ((err = uml_net_rx(dev)) > 0) ;
178
179	spin_lock(&opened_lock);
180	list_add(&lp->list, &opened);
181	spin_unlock(&opened_lock);
182
183	return 0;
184out_close:
185	if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
186	lp->fd = -1;
187out:
188	return err;
189}
190
191static int uml_net_close(struct net_device *dev)
192{
193	struct uml_net_private *lp = netdev_priv(dev);
194
195	netif_stop_queue(dev);
196
197	um_free_irq(dev->irq, dev);
198	if (lp->close != NULL)
199		(*lp->close)(lp->fd, &lp->user);
200	lp->fd = -1;
201
202	spin_lock(&opened_lock);
203	list_del(&lp->list);
204	spin_unlock(&opened_lock);
205
206	return 0;
207}
208
209static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
210{
211	struct uml_net_private *lp = netdev_priv(dev);
212	unsigned long flags;
213	int len;
214
215	netif_stop_queue(dev);
216
217	spin_lock_irqsave(&lp->lock, flags);
218
219	len = (*lp->write)(lp->fd, skb, lp);
220	skb_tx_timestamp(skb);
221
222	if (len == skb->len) {
223		dev->stats.tx_packets++;
224		dev->stats.tx_bytes += skb->len;
225		netif_trans_update(dev);
226		netif_start_queue(dev);
227
228		/* this is normally done in the interrupt when tx finishes */
229		netif_wake_queue(dev);
230	}
231	else if (len == 0) {
232		netif_start_queue(dev);
233		dev->stats.tx_dropped++;
234	}
235	else {
236		netif_start_queue(dev);
237		printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
238	}
239
240	spin_unlock_irqrestore(&lp->lock, flags);
241
242	dev_consume_skb_any(skb);
243
244	return NETDEV_TX_OK;
245}
246
247static void uml_net_set_multicast_list(struct net_device *dev)
248{
249	return;
250}
251
252static void uml_net_tx_timeout(struct net_device *dev)
253{
254	netif_trans_update(dev);
255	netif_wake_queue(dev);
256}
257
 
 
 
 
 
 
 
258#ifdef CONFIG_NET_POLL_CONTROLLER
259static void uml_net_poll_controller(struct net_device *dev)
260{
261	disable_irq(dev->irq);
262	uml_net_interrupt(dev->irq, dev);
263	enable_irq(dev->irq);
264}
265#endif
266
267static void uml_net_get_drvinfo(struct net_device *dev,
268				struct ethtool_drvinfo *info)
269{
270	strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
271	strlcpy(info->version, "42", sizeof(info->version));
272}
273
274static const struct ethtool_ops uml_net_ethtool_ops = {
275	.get_drvinfo	= uml_net_get_drvinfo,
276	.get_link	= ethtool_op_get_link,
277	.get_ts_info	= ethtool_op_get_ts_info,
278};
279
280static void uml_net_user_timer_expire(struct timer_list *t)
281{
282#ifdef undef
283	struct uml_net_private *lp = from_timer(lp, t, tl);
284	struct connection *conn = &lp->user;
285
286	dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
287	do_connect(conn);
288#endif
289}
290
291void uml_net_setup_etheraddr(struct net_device *dev, char *str)
292{
293	unsigned char *addr = dev->dev_addr;
294	char *end;
295	int i;
296
297	if (str == NULL)
298		goto random;
299
300	for (i = 0; i < 6; i++) {
301		addr[i] = simple_strtoul(str, &end, 16);
302		if ((end == str) ||
303		   ((*end != ':') && (*end != ',') && (*end != '\0'))) {
304			printk(KERN_ERR
305			       "setup_etheraddr: failed to parse '%s' "
306			       "as an ethernet address\n", str);
307			goto random;
308		}
309		str = end + 1;
310	}
311	if (is_multicast_ether_addr(addr)) {
312		printk(KERN_ERR
313		       "Attempt to assign a multicast ethernet address to a "
314		       "device disallowed\n");
315		goto random;
316	}
317	if (!is_valid_ether_addr(addr)) {
318		printk(KERN_ERR
319		       "Attempt to assign an invalid ethernet address to a "
320		       "device disallowed\n");
321		goto random;
322	}
323	if (!is_local_ether_addr(addr)) {
324		printk(KERN_WARNING
325		       "Warning: Assigning a globally valid ethernet "
326		       "address to a device\n");
327		printk(KERN_WARNING "You should set the 2nd rightmost bit in "
328		       "the first byte of the MAC,\n");
329		printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n",
330		       addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4],
331		       addr[5]);
332	}
333	return;
334
335random:
336	printk(KERN_INFO
337	       "Choosing a random ethernet address for device %s\n", dev->name);
338	eth_hw_addr_random(dev);
 
339}
340
341static DEFINE_SPINLOCK(devices_lock);
342static LIST_HEAD(devices);
343
344static struct platform_driver uml_net_driver = {
345	.driver = {
346		.name  = DRIVER_NAME,
347	},
348};
349
350static void net_device_release(struct device *dev)
351{
352	struct uml_net *device = dev_get_drvdata(dev);
353	struct net_device *netdev = device->dev;
354	struct uml_net_private *lp = netdev_priv(netdev);
355
356	if (lp->remove != NULL)
357		(*lp->remove)(&lp->user);
358	list_del(&device->list);
359	kfree(device);
360	free_netdev(netdev);
361}
362
363static const struct net_device_ops uml_netdev_ops = {
364	.ndo_open 		= uml_net_open,
365	.ndo_stop 		= uml_net_close,
366	.ndo_start_xmit 	= uml_net_start_xmit,
367	.ndo_set_rx_mode	= uml_net_set_multicast_list,
368	.ndo_tx_timeout 	= uml_net_tx_timeout,
369	.ndo_set_mac_address	= eth_mac_addr,
 
370	.ndo_validate_addr	= eth_validate_addr,
371#ifdef CONFIG_NET_POLL_CONTROLLER
372	.ndo_poll_controller = uml_net_poll_controller,
373#endif
374};
375
376/*
377 * Ensures that platform_driver_register is called only once by
378 * eth_configure.  Will be set in an initcall.
379 */
380static int driver_registered;
381
382static void eth_configure(int n, void *init, char *mac,
383			  struct transport *transport, gfp_t gfp_mask)
384{
385	struct uml_net *device;
386	struct net_device *dev;
387	struct uml_net_private *lp;
388	int err, size;
 
389
390	size = transport->private_size + sizeof(struct uml_net_private);
391
392	device = kzalloc(sizeof(*device), gfp_mask);
393	if (device == NULL) {
394		printk(KERN_ERR "eth_configure failed to allocate struct "
395		       "uml_net\n");
396		return;
397	}
398
399	dev = alloc_etherdev(size);
400	if (dev == NULL) {
401		printk(KERN_ERR "eth_configure: failed to allocate struct "
402		       "net_device for eth%d\n", n);
403		goto out_free_device;
404	}
405
406	INIT_LIST_HEAD(&device->list);
407	device->index = n;
408
409	/* If this name ends up conflicting with an existing registered
410	 * netdevice, that is OK, register_netdev{,ice}() will notice this
411	 * and fail.
412	 */
413	snprintf(dev->name, sizeof(dev->name), "eth%d", n);
414
415	uml_net_setup_etheraddr(dev, mac);
416
417	printk(KERN_INFO "Netdevice %d (%pM) : ", n, dev->dev_addr);
418
419	lp = netdev_priv(dev);
420	/* This points to the transport private data. It's still clear, but we
421	 * must memset it to 0 *now*. Let's help the drivers. */
422	memset(lp, 0, size);
423	INIT_WORK(&lp->work, uml_dev_close);
424
425	/* sysfs register */
426	if (!driver_registered) {
427		platform_driver_register(&uml_net_driver);
428		driver_registered = 1;
429	}
430	device->pdev.id = n;
431	device->pdev.name = DRIVER_NAME;
432	device->pdev.dev.release = net_device_release;
433	dev_set_drvdata(&device->pdev.dev, device);
434	if (platform_device_register(&device->pdev))
435		goto out_free_netdev;
436	SET_NETDEV_DEV(dev,&device->pdev.dev);
437
438	device->dev = dev;
439
440	/*
441	 * These just fill in a data structure, so there's no failure
442	 * to be worried about.
443	 */
444	(*transport->kern->init)(dev, init);
445
446	*lp = ((struct uml_net_private)
447		{ .list  		= LIST_HEAD_INIT(lp->list),
448		  .dev 			= dev,
449		  .fd 			= -1,
450		  .mac 			= { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
451		  .max_packet		= transport->user->max_packet,
452		  .protocol 		= transport->kern->protocol,
453		  .open 		= transport->user->open,
454		  .close 		= transport->user->close,
455		  .remove 		= transport->user->remove,
456		  .read 		= transport->kern->read,
457		  .write 		= transport->kern->write,
458		  .add_address 		= transport->user->add_address,
459		  .delete_address  	= transport->user->delete_address });
460
461	timer_setup(&lp->tl, uml_net_user_timer_expire, 0);
462	spin_lock_init(&lp->lock);
463	memcpy(lp->mac, dev->dev_addr, sizeof(lp->mac));
 
464
465	if ((transport->user->init != NULL) &&
466	    ((*transport->user->init)(&lp->user, dev) != 0))
467		goto out_unregister;
468
 
 
 
 
 
469	dev->mtu = transport->user->mtu;
470	dev->netdev_ops = &uml_netdev_ops;
471	dev->ethtool_ops = &uml_net_ethtool_ops;
472	dev->watchdog_timeo = (HZ >> 1);
473	dev->irq = UM_ETH_IRQ;
474
475	err = update_drop_skb(lp->max_packet);
476	if (err)
477		goto out_undo_user_init;
478
479	rtnl_lock();
480	err = register_netdevice(dev);
481	rtnl_unlock();
482	if (err)
483		goto out_undo_user_init;
484
485	spin_lock(&devices_lock);
486	list_add(&device->list, &devices);
487	spin_unlock(&devices_lock);
488
489	return;
490
491out_undo_user_init:
492	if (transport->user->remove != NULL)
493		(*transport->user->remove)(&lp->user);
494out_unregister:
495	platform_device_unregister(&device->pdev);
496	return; /* platform_device_unregister frees dev and device */
497out_free_netdev:
498	free_netdev(dev);
499out_free_device:
500	kfree(device);
501}
502
503static struct uml_net *find_device(int n)
504{
505	struct uml_net *device;
506	struct list_head *ele;
507
508	spin_lock(&devices_lock);
509	list_for_each(ele, &devices) {
510		device = list_entry(ele, struct uml_net, list);
511		if (device->index == n)
512			goto out;
513	}
514	device = NULL;
515 out:
516	spin_unlock(&devices_lock);
517	return device;
518}
519
520static int eth_parse(char *str, int *index_out, char **str_out,
521		     char **error_out)
522{
523	char *end;
524	int n, err = -EINVAL;
525
526	n = simple_strtoul(str, &end, 0);
527	if (end == str) {
528		*error_out = "Bad device number";
529		return err;
530	}
531
532	str = end;
533	if (*str != '=') {
534		*error_out = "Expected '=' after device number";
535		return err;
536	}
537
538	str++;
539	if (find_device(n)) {
540		*error_out = "Device already configured";
541		return err;
542	}
543
544	*index_out = n;
545	*str_out = str;
546	return 0;
547}
548
549struct eth_init {
550	struct list_head list;
551	char *init;
552	int index;
553};
554
555static DEFINE_SPINLOCK(transports_lock);
556static LIST_HEAD(transports);
557
558/* Filled in during early boot */
559static LIST_HEAD(eth_cmd_line);
560
561static int check_transport(struct transport *transport, char *eth, int n,
562			   void **init_out, char **mac_out, gfp_t gfp_mask)
563{
564	int len;
565
566	len = strlen(transport->name);
567	if (strncmp(eth, transport->name, len))
568		return 0;
569
570	eth += len;
571	if (*eth == ',')
572		eth++;
573	else if (*eth != '\0')
574		return 0;
575
576	*init_out = kmalloc(transport->setup_size, gfp_mask);
577	if (*init_out == NULL)
578		return 1;
579
580	if (!transport->setup(eth, mac_out, *init_out)) {
581		kfree(*init_out);
582		*init_out = NULL;
583	}
584	return 1;
585}
586
587void register_transport(struct transport *new)
588{
589	struct list_head *ele, *next;
590	struct eth_init *eth;
591	void *init;
592	char *mac = NULL;
593	int match;
594
595	spin_lock(&transports_lock);
596	BUG_ON(!list_empty(&new->list));
597	list_add(&new->list, &transports);
598	spin_unlock(&transports_lock);
599
600	list_for_each_safe(ele, next, &eth_cmd_line) {
601		eth = list_entry(ele, struct eth_init, list);
602		match = check_transport(new, eth->init, eth->index, &init,
603					&mac, GFP_KERNEL);
604		if (!match)
605			continue;
606		else if (init != NULL) {
607			eth_configure(eth->index, init, mac, new, GFP_KERNEL);
608			kfree(init);
609		}
610		list_del(&eth->list);
611	}
612}
613
614static int eth_setup_common(char *str, int index)
615{
616	struct list_head *ele;
617	struct transport *transport;
618	void *init;
619	char *mac = NULL;
620	int found = 0;
621
622	spin_lock(&transports_lock);
623	list_for_each(ele, &transports) {
624		transport = list_entry(ele, struct transport, list);
625	        if (!check_transport(transport, str, index, &init,
626					&mac, GFP_ATOMIC))
627			continue;
628		if (init != NULL) {
629			eth_configure(index, init, mac, transport, GFP_ATOMIC);
630			kfree(init);
631		}
632		found = 1;
633		break;
634	}
635
636	spin_unlock(&transports_lock);
637	return found;
638}
639
640static int __init eth_setup(char *str)
641{
642	struct eth_init *new;
643	char *error;
644	int n, err;
645
646	err = eth_parse(str, &n, &str, &error);
647	if (err) {
648		printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
649		       str, error);
650		return 1;
651	}
652
653	new = alloc_bootmem(sizeof(*new));
 
 
 
 
654
655	INIT_LIST_HEAD(&new->list);
656	new->index = n;
657	new->init = str;
658
659	list_add_tail(&new->list, &eth_cmd_line);
660	return 1;
661}
662
663__setup("eth", eth_setup);
664__uml_help(eth_setup,
665"eth[0-9]+=<transport>,<options>\n"
666"    Configure a network device.\n\n"
667);
668
669static int net_config(char *str, char **error_out)
670{
671	int n, err;
672
673	err = eth_parse(str, &n, &str, error_out);
674	if (err)
675		return err;
676
677	/* This string is broken up and the pieces used by the underlying
678	 * driver.  So, it is freed only if eth_setup_common fails.
679	 */
680	str = kstrdup(str, GFP_KERNEL);
681	if (str == NULL) {
682	        *error_out = "net_config failed to strdup string";
683		return -ENOMEM;
684	}
685	err = !eth_setup_common(str, n);
686	if (err)
687		kfree(str);
688	return err;
689}
690
691static int net_id(char **str, int *start_out, int *end_out)
692{
693	char *end;
694	int n;
695
696	n = simple_strtoul(*str, &end, 0);
697	if ((*end != '\0') || (end == *str))
698		return -1;
699
700	*start_out = n;
701	*end_out = n;
702	*str = end;
703	return n;
704}
705
706static int net_remove(int n, char **error_out)
707{
708	struct uml_net *device;
709	struct net_device *dev;
710	struct uml_net_private *lp;
711
712	device = find_device(n);
713	if (device == NULL)
714		return -ENODEV;
715
716	dev = device->dev;
717	lp = netdev_priv(dev);
718	if (lp->fd > 0)
719		return -EBUSY;
720	unregister_netdev(dev);
721	platform_device_unregister(&device->pdev);
722
723	return 0;
724}
725
726static struct mc_device net_mc = {
727	.list		= LIST_HEAD_INIT(net_mc.list),
728	.name		= "eth",
729	.config		= net_config,
730	.get_config	= NULL,
731	.id		= net_id,
732	.remove		= net_remove,
733};
734
735#ifdef CONFIG_INET
736static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
737			      void *ptr)
738{
739	struct in_ifaddr *ifa = ptr;
740	struct net_device *dev = ifa->ifa_dev->dev;
741	struct uml_net_private *lp;
742	void (*proc)(unsigned char *, unsigned char *, void *);
743	unsigned char addr_buf[4], netmask_buf[4];
744
745	if (dev->netdev_ops->ndo_open != uml_net_open)
746		return NOTIFY_DONE;
747
748	lp = netdev_priv(dev);
749
750	proc = NULL;
751	switch (event) {
752	case NETDEV_UP:
753		proc = lp->add_address;
754		break;
755	case NETDEV_DOWN:
756		proc = lp->delete_address;
757		break;
758	}
759	if (proc != NULL) {
760		memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
761		memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
762		(*proc)(addr_buf, netmask_buf, &lp->user);
763	}
764	return NOTIFY_DONE;
765}
766
767/* uml_net_init shouldn't be called twice on two CPUs at the same time */
768static struct notifier_block uml_inetaddr_notifier = {
769	.notifier_call		= uml_inetaddr_event,
770};
771
772static void inet_register(void)
773{
774	struct list_head *ele;
775	struct uml_net_private *lp;
776	struct in_device *ip;
777	struct in_ifaddr *in;
778
779	register_inetaddr_notifier(&uml_inetaddr_notifier);
780
781	/* Devices may have been opened already, so the uml_inetaddr_notifier
782	 * didn't get a chance to run for them.  This fakes it so that
783	 * addresses which have already been set up get handled properly.
784	 */
785	spin_lock(&opened_lock);
786	list_for_each(ele, &opened) {
787		lp = list_entry(ele, struct uml_net_private, list);
788		ip = lp->dev->ip_ptr;
789		if (ip == NULL)
790			continue;
791		in = ip->ifa_list;
792		while (in != NULL) {
793			uml_inetaddr_event(NULL, NETDEV_UP, in);
794			in = in->ifa_next;
795		}
796	}
797	spin_unlock(&opened_lock);
798}
799#else
800static inline void inet_register(void)
801{
802}
803#endif
804
805static int uml_net_init(void)
806{
807	mconsole_register_dev(&net_mc);
808	inet_register();
809	return 0;
810}
811
812__initcall(uml_net_init);
813
814static void close_devices(void)
815{
816	struct list_head *ele;
817	struct uml_net_private *lp;
818
819	spin_lock(&opened_lock);
820	list_for_each(ele, &opened) {
821		lp = list_entry(ele, struct uml_net_private, list);
822		um_free_irq(lp->dev->irq, lp->dev);
823		if ((lp->close != NULL) && (lp->fd >= 0))
824			(*lp->close)(lp->fd, &lp->user);
825		if (lp->remove != NULL)
826			(*lp->remove)(&lp->user);
827	}
828	spin_unlock(&opened_lock);
829}
830
831__uml_exitcall(close_devices);
832
833void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
834					void *),
835		    void *arg)
836{
837	struct net_device *dev = d;
838	struct in_device *ip = dev->ip_ptr;
839	struct in_ifaddr *in;
840	unsigned char address[4], netmask[4];
841
842	if (ip == NULL) return;
843	in = ip->ifa_list;
844	while (in != NULL) {
845		memcpy(address, &in->ifa_address, sizeof(address));
846		memcpy(netmask, &in->ifa_mask, sizeof(netmask));
847		(*cb)(address, netmask, arg);
848		in = in->ifa_next;
849	}
850}
851
852int dev_netmask(void *d, void *m)
853{
854	struct net_device *dev = d;
855	struct in_device *ip = dev->ip_ptr;
856	struct in_ifaddr *in;
857	__be32 *mask_out = m;
858
859	if (ip == NULL)
860		return 1;
861
862	in = ip->ifa_list;
863	if (in == NULL)
864		return 1;
865
866	*mask_out = in->ifa_mask;
867	return 0;
868}
869
870void *get_output_buffer(int *len_out)
871{
872	void *ret;
873
874	ret = (void *) __get_free_pages(GFP_KERNEL, 0);
875	if (ret) *len_out = PAGE_SIZE;
876	else *len_out = 0;
877	return ret;
878}
879
880void free_output_buffer(void *buffer)
881{
882	free_pages((unsigned long) buffer, 0);
883}
884
885int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
886		     char **gate_addr)
887{
888	char *remain;
889
890	remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
891	if (remain != NULL) {
892		printk(KERN_ERR "tap_setup_common - Extra garbage on "
893		       "specification : '%s'\n", remain);
894		return 1;
895	}
896
897	return 0;
898}
899
900unsigned short eth_protocol(struct sk_buff *skb)
901{
902	return eth_type_trans(skb, skb->dev);
903}