uml: correctly handle skb allocation failures
[safe/jmp/linux-2.6] / arch / um / drivers / net_kern.c
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/spinlock.h>
20 #include "init.h"
21 #include "irq_kern.h"
22 #include "irq_user.h"
23 #include "mconsole_kern.h"
24 #include "net_kern.h"
25 #include "net_user.h"
26
27 static inline void set_ether_mac(struct net_device *dev, unsigned char *addr)
28 {
29         memcpy(dev->dev_addr, addr, ETH_ALEN);
30 }
31
32 #define DRIVER_NAME "uml-netdev"
33
34 static DEFINE_SPINLOCK(opened_lock);
35 static LIST_HEAD(opened);
36
37 /*
38  * The drop_skb is used when we can't allocate an skb.  The
39  * packet is read into drop_skb in order to get the data off the
40  * connection to the host.
41  * It is reallocated whenever a maximum packet size is seen which is
42  * larger than any seen before.  update_drop_skb is called from
43  * eth_configure when a new interface is added.
44  */
45 static DEFINE_SPINLOCK(drop_lock);
46 static struct sk_buff *drop_skb;
47 static int drop_max;
48
49 static int update_drop_skb(int max)
50 {
51         struct sk_buff *new;
52         unsigned long flags;
53         int err = 0;
54
55         spin_lock_irqsave(&drop_lock, flags);
56
57         if (max <= drop_max)
58                 goto out;
59
60         err = -ENOMEM;
61         new = dev_alloc_skb(max);
62         if (new == NULL)
63                 goto out;
64
65         skb_put(new, max);
66
67         kfree_skb(drop_skb);
68         drop_skb = new;
69         drop_max = max;
70         err = 0;
71 out:
72         spin_unlock_irqrestore(&drop_lock, flags);
73
74         return err;
75 }
76
77 static int uml_net_rx(struct net_device *dev)
78 {
79         struct uml_net_private *lp = dev->priv;
80         int pkt_len;
81         struct sk_buff *skb;
82
83         /* If we can't allocate memory, try again next round. */
84         skb = dev_alloc_skb(lp->max_packet);
85         if (skb == NULL) {
86                 drop_skb->dev = dev;
87                 /* Read a packet into drop_skb and don't do anything with it. */
88                 (*lp->read)(lp->fd, drop_skb, lp);
89                 lp->stats.rx_dropped++;
90                 return 0;
91         }
92
93         skb->dev = dev;
94         skb_put(skb, lp->max_packet);
95         skb_reset_mac_header(skb);
96         pkt_len = (*lp->read)(lp->fd, skb, lp);
97
98         if (pkt_len > 0) {
99                 skb_trim(skb, pkt_len);
100                 skb->protocol = (*lp->protocol)(skb);
101                 netif_rx(skb);
102
103                 lp->stats.rx_bytes += skb->len;
104                 lp->stats.rx_packets++;
105                 return pkt_len;
106         }
107
108         kfree_skb(skb);
109         return pkt_len;
110 }
111
112 static void uml_dev_close(struct work_struct *work)
113 {
114         struct uml_net_private *lp =
115                 container_of(work, struct uml_net_private, work);
116         dev_close(lp->dev);
117 }
118
119 irqreturn_t uml_net_interrupt(int irq, void *dev_id)
120 {
121         struct net_device *dev = dev_id;
122         struct uml_net_private *lp = dev->priv;
123         int err;
124
125         if (!netif_running(dev))
126                 return IRQ_NONE;
127
128         spin_lock(&lp->lock);
129         while ((err = uml_net_rx(dev)) > 0) ;
130         if (err < 0) {
131                 printk(KERN_ERR
132                        "Device '%s' read returned %d, shutting it down\n",
133                        dev->name, err);
134                 /* dev_close can't be called in interrupt context, and takes
135                  * again lp->lock.
136                  * And dev_close() can be safely called multiple times on the
137                  * same device, since it tests for (dev->flags & IFF_UP). So
138                  * there's no harm in delaying the device shutdown.
139                  * Furthermore, the workqueue will not re-enqueue an already
140                  * enqueued work item. */
141                 schedule_work(&lp->work);
142                 goto out;
143         }
144         reactivate_fd(lp->fd, UM_ETH_IRQ);
145
146 out:
147         spin_unlock(&lp->lock);
148         return IRQ_HANDLED;
149 }
150
151 static int uml_net_open(struct net_device *dev)
152 {
153         struct uml_net_private *lp = dev->priv;
154         int err;
155
156         if (lp->fd >= 0) {
157                 err = -ENXIO;
158                 goto out;
159         }
160
161         lp->fd = (*lp->open)(&lp->user);
162         if (lp->fd < 0) {
163                 err = lp->fd;
164                 goto out;
165         }
166
167         err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
168                              IRQF_DISABLED | IRQF_SHARED, dev->name, dev);
169         if (err != 0) {
170                 printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
171                 err = -ENETUNREACH;
172                 goto out_close;
173         }
174
175         lp->tl.data = (unsigned long) &lp->user;
176         netif_start_queue(dev);
177
178         /* clear buffer - it can happen that the host side of the interface
179          * is full when we get here.  In this case, new data is never queued,
180          * SIGIOs never arrive, and the net never works.
181          */
182         while ((err = uml_net_rx(dev)) > 0) ;
183
184         spin_lock(&opened_lock);
185         list_add(&lp->list, &opened);
186         spin_unlock(&opened_lock);
187
188         return 0;
189 out_close:
190         if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
191         lp->fd = -1;
192 out:
193         return err;
194 }
195
196 static int uml_net_close(struct net_device *dev)
197 {
198         struct uml_net_private *lp = dev->priv;
199
200         netif_stop_queue(dev);
201
202         free_irq(dev->irq, dev);
203         if (lp->close != NULL)
204                 (*lp->close)(lp->fd, &lp->user);
205         lp->fd = -1;
206
207         spin_lock(&opened_lock);
208         list_del(&lp->list);
209         spin_unlock(&opened_lock);
210
211         return 0;
212 }
213
214 static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
215 {
216         struct uml_net_private *lp = dev->priv;
217         unsigned long flags;
218         int len;
219
220         netif_stop_queue(dev);
221
222         spin_lock_irqsave(&lp->lock, flags);
223
224         len = (*lp->write)(lp->fd, skb, lp);
225
226         if (len == skb->len) {
227                 lp->stats.tx_packets++;
228                 lp->stats.tx_bytes += skb->len;
229                 dev->trans_start = jiffies;
230                 netif_start_queue(dev);
231
232                 /* this is normally done in the interrupt when tx finishes */
233                 netif_wake_queue(dev);
234         }
235         else if (len == 0) {
236                 netif_start_queue(dev);
237                 lp->stats.tx_dropped++;
238         }
239         else {
240                 netif_start_queue(dev);
241                 printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
242         }
243
244         spin_unlock_irqrestore(&lp->lock, flags);
245
246         dev_kfree_skb(skb);
247
248         return 0;
249 }
250
251 static struct net_device_stats *uml_net_get_stats(struct net_device *dev)
252 {
253         struct uml_net_private *lp = dev->priv;
254         return &lp->stats;
255 }
256
257 static void uml_net_set_multicast_list(struct net_device *dev)
258 {
259         if (dev->flags & IFF_PROMISC)
260                 return;
261         else if (dev->mc_count)
262                 dev->flags |= IFF_ALLMULTI;
263         else dev->flags &= ~IFF_ALLMULTI;
264 }
265
266 static void uml_net_tx_timeout(struct net_device *dev)
267 {
268         dev->trans_start = jiffies;
269         netif_wake_queue(dev);
270 }
271
272 static int uml_net_set_mac(struct net_device *dev, void *addr)
273 {
274         struct uml_net_private *lp = dev->priv;
275         struct sockaddr *hwaddr = addr;
276
277         spin_lock_irq(&lp->lock);
278         set_ether_mac(dev, hwaddr->sa_data);
279         spin_unlock_irq(&lp->lock);
280
281         return 0;
282 }
283
284 static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
285 {
286         dev->mtu = new_mtu;
287
288         return 0;
289 }
290
291 static void uml_net_get_drvinfo(struct net_device *dev,
292                                 struct ethtool_drvinfo *info)
293 {
294         strcpy(info->driver, DRIVER_NAME);
295         strcpy(info->version, "42");
296 }
297
298 static struct ethtool_ops uml_net_ethtool_ops = {
299         .get_drvinfo    = uml_net_get_drvinfo,
300         .get_link       = ethtool_op_get_link,
301 };
302
303 void uml_net_user_timer_expire(unsigned long _conn)
304 {
305 #ifdef undef
306         struct connection *conn = (struct connection *)_conn;
307
308         dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
309         do_connect(conn);
310 #endif
311 }
312
313 static void setup_etheraddr(char *str, unsigned char *addr, char *name)
314 {
315         char *end;
316         int i;
317
318         if (str == NULL)
319                 goto random;
320
321         for (i = 0;i < 6; i++) {
322                 addr[i] = simple_strtoul(str, &end, 16);
323                 if ((end == str) ||
324                    ((*end != ':') && (*end != ',') && (*end != '\0'))) {
325                         printk(KERN_ERR
326                                "setup_etheraddr: failed to parse '%s' "
327                                "as an ethernet address\n", str);
328                         goto random;
329                 }
330                 str = end + 1;
331         }
332         if (is_multicast_ether_addr(addr)) {
333                 printk(KERN_ERR
334                        "Attempt to assign a multicast ethernet address to a "
335                        "device disallowed\n");
336                 goto random;
337         }
338         if (!is_valid_ether_addr(addr)) {
339                 printk(KERN_ERR
340                        "Attempt to assign an invalid ethernet address to a "
341                        "device disallowed\n");
342                 goto random;
343         }
344         if (!is_local_ether_addr(addr)) {
345                 printk(KERN_WARNING
346                        "Warning: attempt to assign a globally valid ethernet "
347                        "address to a device\n");
348                 printk(KERN_WARNING "You should better enable the 2nd "
349                        "rightmost bit in the first byte of the MAC,\n");
350                 printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n",
351                        addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4],
352                        addr[5]);
353                 goto random;
354         }
355         return;
356
357 random:
358         printk(KERN_INFO
359                "Choosing a random ethernet address for device %s\n", name);
360         random_ether_addr(addr);
361 }
362
363 static DEFINE_SPINLOCK(devices_lock);
364 static LIST_HEAD(devices);
365
366 static struct platform_driver uml_net_driver = {
367         .driver = {
368                 .name  = DRIVER_NAME,
369         },
370 };
371 static int driver_registered;
372
373 static void net_device_release(struct device *dev)
374 {
375         struct uml_net *device = dev->driver_data;
376         struct net_device *netdev = device->dev;
377         struct uml_net_private *lp = netdev->priv;
378
379         if (lp->remove != NULL)
380                 (*lp->remove)(&lp->user);
381         list_del(&device->list);
382         kfree(device);
383         free_netdev(netdev);
384 }
385
386 static void eth_configure(int n, void *init, char *mac,
387                           struct transport *transport)
388 {
389         struct uml_net *device;
390         struct net_device *dev;
391         struct uml_net_private *lp;
392         int err, size;
393
394         size = transport->private_size + sizeof(struct uml_net_private);
395
396         device = kzalloc(sizeof(*device), GFP_KERNEL);
397         if (device == NULL) {
398                 printk(KERN_ERR "eth_configure failed to allocate struct "
399                        "uml_net\n");
400                 return;
401         }
402
403         dev = alloc_etherdev(size);
404         if (dev == NULL) {
405                 printk(KERN_ERR "eth_configure: failed to allocate struct "
406                        "net_device for eth%d\n", n);
407                 goto out_free_device;
408         }
409
410         INIT_LIST_HEAD(&device->list);
411         device->index = n;
412
413         /* If this name ends up conflicting with an existing registered
414          * netdevice, that is OK, register_netdev{,ice}() will notice this
415          * and fail.
416          */
417         snprintf(dev->name, sizeof(dev->name), "eth%d", n);
418
419         setup_etheraddr(mac, device->mac, dev->name);
420
421         printk(KERN_INFO "Netdevice %d ", n);
422         printk("(%02x:%02x:%02x:%02x:%02x:%02x) ",
423                device->mac[0], device->mac[1],
424                device->mac[2], device->mac[3],
425                device->mac[4], device->mac[5]);
426         printk(": ");
427
428         lp = dev->priv;
429         /* This points to the transport private data. It's still clear, but we
430          * must memset it to 0 *now*. Let's help the drivers. */
431         memset(lp, 0, size);
432         INIT_WORK(&lp->work, uml_dev_close);
433
434         /* sysfs register */
435         if (!driver_registered) {
436                 platform_driver_register(&uml_net_driver);
437                 driver_registered = 1;
438         }
439         device->pdev.id = n;
440         device->pdev.name = DRIVER_NAME;
441         device->pdev.dev.release = net_device_release;
442         device->pdev.dev.driver_data = device;
443         if (platform_device_register(&device->pdev))
444                 goto out_free_netdev;
445         SET_NETDEV_DEV(dev,&device->pdev.dev);
446
447         device->dev = dev;
448
449         /*
450          * These just fill in a data structure, so there's no failure
451          * to be worried about.
452          */
453         (*transport->kern->init)(dev, init);
454
455         *lp = ((struct uml_net_private)
456                 { .list                 = LIST_HEAD_INIT(lp->list),
457                   .dev                  = dev,
458                   .fd                   = -1,
459                   .mac                  = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
460                   .max_packet           = transport->user->max_packet,
461                   .protocol             = transport->kern->protocol,
462                   .open                 = transport->user->open,
463                   .close                = transport->user->close,
464                   .remove               = transport->user->remove,
465                   .read                 = transport->kern->read,
466                   .write                = transport->kern->write,
467                   .add_address          = transport->user->add_address,
468                   .delete_address       = transport->user->delete_address });
469
470         init_timer(&lp->tl);
471         spin_lock_init(&lp->lock);
472         lp->tl.function = uml_net_user_timer_expire;
473         memcpy(lp->mac, device->mac, sizeof(lp->mac));
474
475         if ((transport->user->init != NULL) &&
476             ((*transport->user->init)(&lp->user, dev) != 0))
477                 goto out_unregister;
478
479         set_ether_mac(dev, device->mac);
480         dev->mtu = transport->user->mtu;
481         dev->open = uml_net_open;
482         dev->hard_start_xmit = uml_net_start_xmit;
483         dev->stop = uml_net_close;
484         dev->get_stats = uml_net_get_stats;
485         dev->set_multicast_list = uml_net_set_multicast_list;
486         dev->tx_timeout = uml_net_tx_timeout;
487         dev->set_mac_address = uml_net_set_mac;
488         dev->change_mtu = uml_net_change_mtu;
489         dev->ethtool_ops = &uml_net_ethtool_ops;
490         dev->watchdog_timeo = (HZ >> 1);
491         dev->irq = UM_ETH_IRQ;
492
493         err = update_drop_skb(lp->max_packet);
494         if (err)
495                 goto out_undo_user_init;
496
497         rtnl_lock();
498         err = register_netdevice(dev);
499         rtnl_unlock();
500         if (err)
501                 goto out_undo_user_init;
502
503         spin_lock(&devices_lock);
504         list_add(&device->list, &devices);
505         spin_unlock(&devices_lock);
506
507         return;
508
509 out_undo_user_init:
510         if (transport->user->remove != NULL)
511                 (*transport->user->remove)(&lp->user);
512 out_unregister:
513         platform_device_unregister(&device->pdev);
514         return; /* platform_device_unregister frees dev and device */
515 out_free_netdev:
516         free_netdev(dev);
517 out_free_device:
518         kfree(device);
519 }
520
521 static struct uml_net *find_device(int n)
522 {
523         struct uml_net *device;
524         struct list_head *ele;
525
526         spin_lock(&devices_lock);
527         list_for_each(ele, &devices) {
528                 device = list_entry(ele, struct uml_net, list);
529                 if (device->index == n)
530                         goto out;
531         }
532         device = NULL;
533  out:
534         spin_unlock(&devices_lock);
535         return device;
536 }
537
538 static int eth_parse(char *str, int *index_out, char **str_out,
539                      char **error_out)
540 {
541         char *end;
542         int n, err = -EINVAL;;
543
544         n = simple_strtoul(str, &end, 0);
545         if (end == str) {
546                 *error_out = "Bad device number";
547                 return err;
548         }
549
550         str = end;
551         if (*str != '=') {
552                 *error_out = "Expected '=' after device number";
553                 return err;
554         }
555
556         str++;
557         if (find_device(n)) {
558                 *error_out = "Device already configured";
559                 return err;
560         }
561
562         *index_out = n;
563         *str_out = str;
564         return 0;
565 }
566
567 struct eth_init {
568         struct list_head list;
569         char *init;
570         int index;
571 };
572
573 static DEFINE_SPINLOCK(transports_lock);
574 static LIST_HEAD(transports);
575
576 /* Filled in during early boot */
577 static LIST_HEAD(eth_cmd_line);
578
579 static int check_transport(struct transport *transport, char *eth, int n,
580                            void **init_out, char **mac_out)
581 {
582         int len;
583
584         len = strlen(transport->name);
585         if (strncmp(eth, transport->name, len))
586                 return 0;
587
588         eth += len;
589         if (*eth == ',')
590                 eth++;
591         else if (*eth != '\0')
592                 return 0;
593
594         *init_out = kmalloc(transport->setup_size, GFP_KERNEL);
595         if (*init_out == NULL)
596                 return 1;
597
598         if (!transport->setup(eth, mac_out, *init_out)) {
599                 kfree(*init_out);
600                 *init_out = NULL;
601         }
602         return 1;
603 }
604
605 void register_transport(struct transport *new)
606 {
607         struct list_head *ele, *next;
608         struct eth_init *eth;
609         void *init;
610         char *mac = NULL;
611         int match;
612
613         spin_lock(&transports_lock);
614         BUG_ON(!list_empty(&new->list));
615         list_add(&new->list, &transports);
616         spin_unlock(&transports_lock);
617
618         list_for_each_safe(ele, next, &eth_cmd_line) {
619                 eth = list_entry(ele, struct eth_init, list);
620                 match = check_transport(new, eth->init, eth->index, &init,
621                                         &mac);
622                 if (!match)
623                         continue;
624                 else if (init != NULL) {
625                         eth_configure(eth->index, init, mac, new);
626                         kfree(init);
627                 }
628                 list_del(&eth->list);
629         }
630 }
631
632 static int eth_setup_common(char *str, int index)
633 {
634         struct list_head *ele;
635         struct transport *transport;
636         void *init;
637         char *mac = NULL;
638         int found = 0;
639
640         spin_lock(&transports_lock);
641         list_for_each(ele, &transports) {
642                 transport = list_entry(ele, struct transport, list);
643                 if (!check_transport(transport, str, index, &init, &mac))
644                         continue;
645                 if (init != NULL) {
646                         eth_configure(index, init, mac, transport);
647                         kfree(init);
648                 }
649                 found = 1;
650                 break;
651         }
652
653         spin_unlock(&transports_lock);
654         return found;
655 }
656
657 static int __init eth_setup(char *str)
658 {
659         struct eth_init *new;
660         char *error;
661         int n, err;
662
663         err = eth_parse(str, &n, &str, &error);
664         if (err) {
665                 printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
666                        str, error);
667                 return 1;
668         }
669
670         new = alloc_bootmem(sizeof(*new));
671         if (new == NULL) {
672                 printk(KERN_ERR "eth_init : alloc_bootmem failed\n");
673                 return 1;
674         }
675
676         INIT_LIST_HEAD(&new->list);
677         new->index = n;
678         new->init = str;
679
680         list_add_tail(&new->list, &eth_cmd_line);
681         return 1;
682 }
683
684 __setup("eth", eth_setup);
685 __uml_help(eth_setup,
686 "eth[0-9]+=<transport>,<options>\n"
687 "    Configure a network device.\n\n"
688 );
689
690 static int net_config(char *str, char **error_out)
691 {
692         int n, err;
693
694         err = eth_parse(str, &n, &str, error_out);
695         if (err)
696                 return err;
697
698         /* This string is broken up and the pieces used by the underlying
699          * driver.  So, it is freed only if eth_setup_common fails.
700          */
701         str = kstrdup(str, GFP_KERNEL);
702         if (str == NULL) {
703                 *error_out = "net_config failed to strdup string";
704                 return -ENOMEM;
705         }
706         err = !eth_setup_common(str, n);
707         if (err)
708                 kfree(str);
709         return err;
710 }
711
712 static int net_id(char **str, int *start_out, int *end_out)
713 {
714         char *end;
715         int n;
716
717         n = simple_strtoul(*str, &end, 0);
718         if ((*end != '\0') || (end == *str))
719                 return -1;
720
721         *start_out = n;
722         *end_out = n;
723         *str = end;
724         return n;
725 }
726
727 static int net_remove(int n, char **error_out)
728 {
729         struct uml_net *device;
730         struct net_device *dev;
731         struct uml_net_private *lp;
732
733         device = find_device(n);
734         if (device == NULL)
735                 return -ENODEV;
736
737         dev = device->dev;
738         lp = dev->priv;
739         if (lp->fd > 0)
740                 return -EBUSY;
741         unregister_netdev(dev);
742         platform_device_unregister(&device->pdev);
743
744         return 0;
745 }
746
747 static struct mc_device net_mc = {
748         .list           = LIST_HEAD_INIT(net_mc.list),
749         .name           = "eth",
750         .config         = net_config,
751         .get_config     = NULL,
752         .id             = net_id,
753         .remove         = net_remove,
754 };
755
756 static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
757                               void *ptr)
758 {
759         struct in_ifaddr *ifa = ptr;
760         struct net_device *dev = ifa->ifa_dev->dev;
761         struct uml_net_private *lp;
762         void (*proc)(unsigned char *, unsigned char *, void *);
763         unsigned char addr_buf[4], netmask_buf[4];
764
765         if (dev->open != uml_net_open)
766                 return NOTIFY_DONE;
767
768         lp = dev->priv;
769
770         proc = NULL;
771         switch (event) {
772         case NETDEV_UP:
773                 proc = lp->add_address;
774                 break;
775         case NETDEV_DOWN:
776                 proc = lp->delete_address;
777                 break;
778         }
779         if (proc != NULL) {
780                 memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
781                 memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
782                 (*proc)(addr_buf, netmask_buf, &lp->user);
783         }
784         return NOTIFY_DONE;
785 }
786
787 /* uml_net_init shouldn't be called twice on two CPUs at the same time */
788 struct notifier_block uml_inetaddr_notifier = {
789         .notifier_call          = uml_inetaddr_event,
790 };
791
792 static int uml_net_init(void)
793 {
794         struct list_head *ele;
795         struct uml_net_private *lp;
796         struct in_device *ip;
797         struct in_ifaddr *in;
798
799         mconsole_register_dev(&net_mc);
800         register_inetaddr_notifier(&uml_inetaddr_notifier);
801
802         /* Devices may have been opened already, so the uml_inetaddr_notifier
803          * didn't get a chance to run for them.  This fakes it so that
804          * addresses which have already been set up get handled properly.
805          */
806         spin_lock(&opened_lock);
807         list_for_each(ele, &opened) {
808                 lp = list_entry(ele, struct uml_net_private, list);
809                 ip = lp->dev->ip_ptr;
810                 if (ip == NULL)
811                         continue;
812                 in = ip->ifa_list;
813                 while (in != NULL) {
814                         uml_inetaddr_event(NULL, NETDEV_UP, in);
815                         in = in->ifa_next;
816                 }
817         }
818         spin_unlock(&opened_lock);
819
820         return 0;
821 }
822
823 __initcall(uml_net_init);
824
825 static void close_devices(void)
826 {
827         struct list_head *ele;
828         struct uml_net_private *lp;
829
830         spin_lock(&opened_lock);
831         list_for_each(ele, &opened) {
832                 lp = list_entry(ele, struct uml_net_private, list);
833                 free_irq(lp->dev->irq, lp->dev);
834                 if ((lp->close != NULL) && (lp->fd >= 0))
835                         (*lp->close)(lp->fd, &lp->user);
836                 if (lp->remove != NULL)
837                         (*lp->remove)(&lp->user);
838         }
839         spin_unlock(&opened_lock);
840 }
841
842 __uml_exitcall(close_devices);
843
844 void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
845                                         void *),
846                     void *arg)
847 {
848         struct net_device *dev = d;
849         struct in_device *ip = dev->ip_ptr;
850         struct in_ifaddr *in;
851         unsigned char address[4], netmask[4];
852
853         if (ip == NULL) return;
854         in = ip->ifa_list;
855         while (in != NULL) {
856                 memcpy(address, &in->ifa_address, sizeof(address));
857                 memcpy(netmask, &in->ifa_mask, sizeof(netmask));
858                 (*cb)(address, netmask, arg);
859                 in = in->ifa_next;
860         }
861 }
862
863 int dev_netmask(void *d, void *m)
864 {
865         struct net_device *dev = d;
866         struct in_device *ip = dev->ip_ptr;
867         struct in_ifaddr *in;
868         __be32 *mask_out = m;
869
870         if (ip == NULL)
871                 return 1;
872
873         in = ip->ifa_list;
874         if (in == NULL)
875                 return 1;
876
877         *mask_out = in->ifa_mask;
878         return 0;
879 }
880
881 void *get_output_buffer(int *len_out)
882 {
883         void *ret;
884
885         ret = (void *) __get_free_pages(GFP_KERNEL, 0);
886         if (ret) *len_out = PAGE_SIZE;
887         else *len_out = 0;
888         return ret;
889 }
890
891 void free_output_buffer(void *buffer)
892 {
893         free_pages((unsigned long) buffer, 0);
894 }
895
896 int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
897                      char **gate_addr)
898 {
899         char *remain;
900
901         remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
902         if (remain != NULL) {
903                 printk(KERN_ERR "tap_setup_common - Extra garbage on "
904                        "specification : '%s'\n", remain);
905                 return 1;
906         }
907
908         return 0;
909 }
910
911 unsigned short eth_protocol(struct sk_buff *skb)
912 {
913         return eth_type_trans(skb, skb->dev);
914 }