arch/um/drivers/net_kern.c

   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/kernel.h"
   9 #include "linux/netdevice.h"
  10 #include "linux/rtnetlink.h"
  11 #include "linux/skbuff.h"
  12 #include "linux/socket.h"
  13 #include "linux/spinlock.h"
  14 #include "linux/module.h"
  15 #include "linux/init.h"
  16 #include "linux/etherdevice.h"
  17 #include "linux/list.h"
  18 #include "linux/inetdevice.h"
  19 #include "linux/ctype.h"
  20 #include "linux/bootmem.h"
  21 #include "linux/ethtool.h"
  22 #include "linux/platform_device.h"
  23 #include "asm/uaccess.h"
  24 #include "kern_util.h"
  25 #include "net_kern.h"
  26 #include "net_user.h"
  27 #include "mconsole_kern.h"
  28 #include "init.h"
  29 #include "irq_user.h"
  30 #include "irq_kern.h"
  31
  32 static inline void set_ether_mac(struct net_device *dev, unsigned char *addr)
  33 {
  34         memcpy(dev->dev_addr, addr, ETH_ALEN);
  35 }
  36
  37 #define DRIVER_NAME "uml-netdev"
  38
  39 static DEFINE_SPINLOCK(opened_lock);
  40 static LIST_HEAD(opened);
  41
  42 static int uml_net_rx(struct net_device *dev)
  43 {
  44         struct uml_net_private *lp = dev->priv;
  45         int pkt_len;
  46         struct sk_buff *skb;
  47
  48         /* If we can't allocate memory, try again next round. */
  49         skb = dev_alloc_skb(dev->mtu);
  50         if (skb == NULL) {
  51                 lp->stats.rx_dropped++;
  52                 return 0;
  53         }
  54
  55         skb->dev = dev;
  56         skb_put(skb, dev->mtu);
  57         skb_reset_mac_header(skb);
  58         pkt_len = (*lp->read)(lp->fd, &skb, lp);
  59
  60         if (pkt_len > 0) {
  61                 skb_trim(skb, pkt_len);
  62                 skb->protocol = (*lp->protocol)(skb);
  63                 netif_rx(skb);
  64
  65                 lp->stats.rx_bytes += skb->len;
  66                 lp->stats.rx_packets++;
  67                 return pkt_len;
  68         }
  69
  70         kfree_skb(skb);
  71         return pkt_len;
  72 }
  73
  74 static void uml_dev_close(struct work_struct *work)
  75 {
  76         struct uml_net_private *lp =
  77                 container_of(work, struct uml_net_private, work);
  78         dev_close(lp->dev);
  79 }
  80
  81 irqreturn_t uml_net_interrupt(int irq, void *dev_id)
  82 {
  83         struct net_device *dev = dev_id;
  84         struct uml_net_private *lp = dev->priv;
  85         int err;
  86
  87         if(!netif_running(dev))
  88                 return(IRQ_NONE);
  89
  90         spin_lock(&lp->lock);
  91         while((err = uml_net_rx(dev)) > 0) ;
  92         if(err < 0) {
  93                 printk(KERN_ERR
  94                        "Device '%s' read returned %d, shutting it down\n",
  95                        dev->name, err);
  96                 /* dev_close can't be called in interrupt context, and takes
  97                  * again lp->lock.
  98                  * And dev_close() can be safely called multiple times on the
  99                  * same device, since it tests for (dev->flags & IFF_UP). So
 100                  * there's no harm in delaying the device shutdown.
 101                  * Furthermore, the workqueue will not re-enqueue an already
 102                  * enqueued work item. */
 103                 schedule_work(&lp->work);
 104                 goto out;
 105         }
 106         reactivate_fd(lp->fd, UM_ETH_IRQ);
 107
 108 out:
 109         spin_unlock(&lp->lock);
 110         return IRQ_HANDLED;
 111 }
 112
 113 static int uml_net_open(struct net_device *dev)
 114 {
 115         struct uml_net_private *lp = dev->priv;
 116         int err;
 117
 118         if(lp->fd >= 0){
 119                 err = -ENXIO;
 120                 goto out;
 121         }
 122
 123         lp->fd = (*lp->open)(&lp->user);
 124         if(lp->fd < 0){
 125                 err = lp->fd;
 126                 goto out;
 127         }
 128
 129         err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
 130                              IRQF_DISABLED | IRQF_SHARED, dev->name, dev);
 131         if(err != 0){
 132                 printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
 133                 err = -ENETUNREACH;
 134                 goto out_close;
 135         }
 136
 137         lp->tl.data = (unsigned long) &lp->user;
 138         netif_start_queue(dev);
 139
 140         /* clear buffer - it can happen that the host side of the interface
 141          * is full when we get here.  In this case, new data is never queued,
 142          * SIGIOs never arrive, and the net never works.
 143          */
 144         while((err = uml_net_rx(dev)) > 0) ;
 145
 146         spin_lock(&opened_lock);
 147         list_add(&lp->list, &opened);
 148         spin_unlock(&opened_lock);
 149
 150         return 0;
 151 out_close:
 152         if(lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
 153         lp->fd = -1;
 154 out:
 155         return err;
 156 }
 157
 158 static int uml_net_close(struct net_device *dev)
 159 {
 160         struct uml_net_private *lp = dev->priv;
 161
 162         netif_stop_queue(dev);
 163
 164         free_irq(dev->irq, dev);
 165         if(lp->close != NULL)
 166                 (*lp->close)(lp->fd, &lp->user);
 167         lp->fd = -1;
 168
 169         spin_lock(&opened_lock);
 170         list_del(&lp->list);
 171         spin_unlock(&opened_lock);
 172
 173         return 0;
 174 }
 175
 176 static int uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
 177 {
 178         struct uml_net_private *lp = dev->priv;
 179         unsigned long flags;
 180         int len;
 181
 182         netif_stop_queue(dev);
 183
 184         spin_lock_irqsave(&lp->lock, flags);
 185
 186         len = (*lp->write)(lp->fd, &skb, lp);
 187
 188         if(len == skb->len) {
 189                 lp->stats.tx_packets++;
 190                 lp->stats.tx_bytes += skb->len;
 191                 dev->trans_start = jiffies;
 192                 netif_start_queue(dev);
 193
 194                 /* this is normally done in the interrupt when tx finishes */
 195                 netif_wake_queue(dev);
 196         }
 197         else if(len == 0){
 198                 netif_start_queue(dev);
 199                 lp->stats.tx_dropped++;
 200         }
 201         else {
 202                 netif_start_queue(dev);
 203                 printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
 204         }
 205
 206         spin_unlock_irqrestore(&lp->lock, flags);
 207
 208         dev_kfree_skb(skb);
 209
 210         return 0;
 211 }
 212
 213 static struct net_device_stats *uml_net_get_stats(struct net_device *dev)
 214 {
 215         struct uml_net_private *lp = dev->priv;
 216         return &lp->stats;
 217 }
 218
 219 static void uml_net_set_multicast_list(struct net_device *dev)
 220 {
 221         if (dev->flags & IFF_PROMISC) return;
 222         else if (dev->mc_count) dev->flags |= IFF_ALLMULTI;
 223         else dev->flags &= ~IFF_ALLMULTI;
 224 }
 225
 226 static void uml_net_tx_timeout(struct net_device *dev)
 227 {
 228         dev->trans_start = jiffies;
 229         netif_wake_queue(dev);
 230 }
 231
 232 static int uml_net_set_mac(struct net_device *dev, void *addr)
 233 {
 234         struct uml_net_private *lp = dev->priv;
 235         struct sockaddr *hwaddr = addr;
 236
 237         spin_lock_irq(&lp->lock);
 238         set_ether_mac(dev, hwaddr->sa_data);
 239         spin_unlock_irq(&lp->lock);
 240
 241         return 0;
 242 }
 243
 244 static int uml_net_change_mtu(struct net_device *dev, int new_mtu)
 245 {
 246         struct uml_net_private *lp = dev->priv;
 247         int err = 0;
 248
 249         spin_lock_irq(&lp->lock);
 250
 251         new_mtu = (*lp->set_mtu)(new_mtu, &lp->user);
 252         if(new_mtu < 0){
 253                 err = new_mtu;
 254                 goto out;
 255         }
 256
 257         dev->mtu = new_mtu;
 258
 259  out:
 260         spin_unlock_irq(&lp->lock);
 261         return err;
 262 }
 263
 264 static void uml_net_get_drvinfo(struct net_device *dev,
 265                                 struct ethtool_drvinfo *info)
 266 {
 267         strcpy(info->driver, DRIVER_NAME);
 268         strcpy(info->version, "42");
 269 }
 270
 271 static struct ethtool_ops uml_net_ethtool_ops = {
 272         .get_drvinfo    = uml_net_get_drvinfo,
 273         .get_link       = ethtool_op_get_link,
 274 };
 275
 276 void uml_net_user_timer_expire(unsigned long _conn)
 277 {
 278 #ifdef undef
 279         struct connection *conn = (struct connection *)_conn;
 280
 281         dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
 282         do_connect(conn);
 283 #endif
 284 }
 285
 286 static void setup_etheraddr(char *str, unsigned char *addr, char *name)
 287 {
 288         char *end;
 289         int i;
 290
 291         if(str == NULL)
 292                 goto random;
 293
 294         for(i=0;i<6;i++){
 295                 addr[i] = simple_strtoul(str, &end, 16);
 296                 if((end == str) ||
 297                    ((*end != ':') && (*end != ',') && (*end != '\0'))){
 298                         printk(KERN_ERR
 299                                "setup_etheraddr: failed to parse '%s' "
 300                                "as an ethernet address\n", str);
 301                         goto random;
 302                 }
 303                 str = end + 1;
 304         }
 305         if (is_multicast_ether_addr(addr)) {
 306                 printk(KERN_ERR
 307                        "Attempt to assign a multicast ethernet address to a "
 308                        "device disallowed\n");
 309                 goto random;
 310         }
 311         if (!is_valid_ether_addr(addr)) {
 312                 printk(KERN_ERR
 313                        "Attempt to assign an invalid ethernet address to a "
 314                        "device disallowed\n");
 315                 goto random;
 316         }
 317         if (!is_local_ether_addr(addr)) {
 318                 printk(KERN_WARNING
 319                        "Warning: attempt to assign a globally valid ethernet address to a "
 320                        "device\n");
 321                 printk(KERN_WARNING "You should better enable the 2nd rightmost bit "
 322                       "in the first byte of the MAC, i.e. "
 323                       "%02x:%02x:%02x:%02x:%02x:%02x\n",
 324                       addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4], addr[5]);
 325         }
 326         return;
 327
 328 random:
 329         printk(KERN_INFO
 330                "Choosing a random ethernet address for device %s\n", name);
 331         random_ether_addr(addr);
 332 }
 333
 334 static DEFINE_SPINLOCK(devices_lock);
 335 static LIST_HEAD(devices);
 336
 337 static struct platform_driver uml_net_driver = {
 338         .driver = {
 339                 .name  = DRIVER_NAME,
 340         },
 341 };
 342 static int driver_registered;
 343
 344 static void net_device_release(struct device *dev)
 345 {
 346         struct uml_net *device = dev->driver_data;
 347         struct net_device *netdev = device->dev;
 348         struct uml_net_private *lp = netdev->priv;
 349
 350         if(lp->remove != NULL)
 351                 (*lp->remove)(&lp->user);
 352         list_del(&device->list);
 353         kfree(device);
 354         free_netdev(netdev);
 355 }
 356
 357 static void eth_configure(int n, void *init, char *mac,
 358                           struct transport *transport)
 359 {
 360         struct uml_net *device;
 361         struct net_device *dev;
 362         struct uml_net_private *lp;
 363         int err, size;
 364
 365         size = transport->private_size + sizeof(struct uml_net_private);
 366
 367         device = kzalloc(sizeof(*device), GFP_KERNEL);
 368         if (device == NULL) {
 369                 printk(KERN_ERR "eth_configure failed to allocate struct "
 370                        "uml_net\n");
 371                 return;
 372         }
 373
 374         dev = alloc_etherdev(size);
 375         if (dev == NULL) {
 376                 printk(KERN_ERR "eth_configure: failed to allocate struct "
 377                        "net_device for eth%d\n", n);
 378                 goto out_free_device;
 379         }
 380
 381         INIT_LIST_HEAD(&device->list);
 382         device->index = n;
 383
 384         /* If this name ends up conflicting with an existing registered
 385          * netdevice, that is OK, register_netdev{,ice}() will notice this
 386          * and fail.
 387          */
 388         snprintf(dev->name, sizeof(dev->name), "eth%d", n);
 389
 390         setup_etheraddr(mac, device->mac, dev->name);
 391
 392         printk(KERN_INFO "Netdevice %d ", n);
 393         printk("(%02x:%02x:%02x:%02x:%02x:%02x) ",
 394                device->mac[0], device->mac[1],
 395                device->mac[2], device->mac[3],
 396                device->mac[4], device->mac[5]);
 397         printk(": ");
 398
 399         lp = dev->priv;
 400         /* This points to the transport private data. It's still clear, but we
 401          * must memset it to 0 *now*. Let's help the drivers. */
 402         memset(lp, 0, size);
 403         INIT_WORK(&lp->work, uml_dev_close);
 404
 405         /* sysfs register */
 406         if (!driver_registered) {
 407                 platform_driver_register(&uml_net_driver);
 408                 driver_registered = 1;
 409         }
 410         device->pdev.id = n;
 411         device->pdev.name = DRIVER_NAME;
 412         device->pdev.dev.release = net_device_release;
 413         device->pdev.dev.driver_data = device;
 414         if(platform_device_register(&device->pdev))
 415                 goto out_free_netdev;
 416         SET_NETDEV_DEV(dev,&device->pdev.dev);
 417
 418         device->dev = dev;
 419
 420         /*
 421          * These just fill in a data structure, so there's no failure
 422          * to be worried about.
 423          */
 424         (*transport->kern->init)(dev, init);
 425
 426         *lp = ((struct uml_net_private)
 427                 { .list                 = LIST_HEAD_INIT(lp->list),
 428                   .dev                  = dev,
 429                   .fd                   = -1,
 430                   .mac                  = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
 431                   .protocol             = transport->kern->protocol,
 432                   .open                 = transport->user->open,
 433                   .close                = transport->user->close,
 434                   .remove               = transport->user->remove,
 435                   .read                 = transport->kern->read,
 436                   .write                = transport->kern->write,
 437                   .add_address          = transport->user->add_address,
 438                   .delete_address       = transport->user->delete_address,
 439                   .set_mtu              = transport->user->set_mtu });
 440
 441         init_timer(&lp->tl);
 442         spin_lock_init(&lp->lock);
 443         lp->tl.function = uml_net_user_timer_expire;
 444         memcpy(lp->mac, device->mac, sizeof(lp->mac));
 445
 446         if ((transport->user->init != NULL) &&
 447             ((*transport->user->init)(&lp->user, dev) != 0))
 448                 goto out_unregister;
 449
 450         set_ether_mac(dev, device->mac);
 451         dev->mtu = transport->user->max_packet;
 452         dev->open = uml_net_open;
 453         dev->hard_start_xmit = uml_net_start_xmit;
 454         dev->stop = uml_net_close;
 455         dev->get_stats = uml_net_get_stats;
 456         dev->set_multicast_list = uml_net_set_multicast_list;
 457         dev->tx_timeout = uml_net_tx_timeout;
 458         dev->set_mac_address = uml_net_set_mac;
 459         dev->change_mtu = uml_net_change_mtu;
 460         dev->ethtool_ops = &uml_net_ethtool_ops;
 461         dev->watchdog_timeo = (HZ >> 1);
 462         dev->irq = UM_ETH_IRQ;
 463
 464         rtnl_lock();
 465         err = register_netdevice(dev);
 466         rtnl_unlock();
 467         if (err)
 468                 goto out_undo_user_init;
 469
 470         spin_lock(&devices_lock);
 471         list_add(&device->list, &devices);
 472         spin_unlock(&devices_lock);
 473
 474         return;
 475
 476 out_undo_user_init:
 477         if (transport->user->remove != NULL)
 478                 (*transport->user->remove)(&lp->user);
 479 out_unregister:
 480         platform_device_unregister(&device->pdev);
 481 out_free_netdev:
 482         free_netdev(dev);
 483 out_free_device:
 484         kfree(device);
 485 }
 486
 487 static struct uml_net *find_device(int n)
 488 {
 489         struct uml_net *device;
 490         struct list_head *ele;
 491
 492         spin_lock(&devices_lock);
 493         list_for_each(ele, &devices){
 494                 device = list_entry(ele, struct uml_net, list);
 495                 if(device->index == n)
 496                         goto out;
 497         }
 498         device = NULL;
 499  out:
 500         spin_unlock(&devices_lock);
 501         return device;
 502 }
 503
 504 static int eth_parse(char *str, int *index_out, char **str_out,
 505                      char **error_out)
 506 {
 507         char *end;
 508         int n, err = -EINVAL;;
 509
 510         n = simple_strtoul(str, &end, 0);
 511         if(end == str){
 512                 *error_out = "Bad device number";
 513                 return err;
 514         }
 515
 516         str = end;
 517         if(*str != '='){
 518                 *error_out = "Expected '=' after device number";
 519                 return err;
 520         }
 521
 522         str++;
 523         if(find_device(n)){
 524                 *error_out = "Device already configured";
 525                 return err;
 526         }
 527
 528         *index_out = n;
 529         *str_out = str;
 530         return 0;
 531 }
 532
 533 struct eth_init {
 534         struct list_head list;
 535         char *init;
 536         int index;
 537 };
 538
 539 static DEFINE_SPINLOCK(transports_lock);
 540 static LIST_HEAD(transports);
 541
 542 /* Filled in during early boot */
 543 static LIST_HEAD(eth_cmd_line);
 544
 545 static int check_transport(struct transport *transport, char *eth, int n,
 546                            void **init_out, char **mac_out)
 547 {
 548         int len;
 549
 550         len = strlen(transport->name);
 551         if(strncmp(eth, transport->name, len))
 552                 return 0;
 553
 554         eth += len;
 555         if(*eth == ',')
 556                 eth++;
 557         else if(*eth != '\0')
 558                 return 0;
 559
 560         *init_out = kmalloc(transport->setup_size, GFP_KERNEL);
 561         if(*init_out == NULL)
 562                 return 1;
 563
 564         if(!transport->setup(eth, mac_out, *init_out)){
 565                 kfree(*init_out);
 566                 *init_out = NULL;
 567         }
 568         return 1;
 569 }
 570
 571 void register_transport(struct transport *new)
 572 {
 573         struct list_head *ele, *next;
 574         struct eth_init *eth;
 575         void *init;
 576         char *mac = NULL;
 577         int match;
 578
 579         spin_lock(&transports_lock);
 580         BUG_ON(!list_empty(&new->list));
 581         list_add(&new->list, &transports);
 582         spin_unlock(&transports_lock);
 583
 584         list_for_each_safe(ele, next, &eth_cmd_line){
 585                 eth = list_entry(ele, struct eth_init, list);
 586                 match = check_transport(new, eth->init, eth->index, &init,
 587                                         &mac);
 588                 if(!match)
 589                         continue;
 590                 else if(init != NULL){
 591                         eth_configure(eth->index, init, mac, new);
 592                         kfree(init);
 593                 }
 594                 list_del(&eth->list);
 595         }
 596 }
 597
 598 static int eth_setup_common(char *str, int index)
 599 {
 600         struct list_head *ele;
 601         struct transport *transport;
 602         void *init;
 603         char *mac = NULL;
 604         int found = 0;
 605
 606         spin_lock(&transports_lock);
 607         list_for_each(ele, &transports){
 608                 transport = list_entry(ele, struct transport, list);
 609                 if(!check_transport(transport, str, index, &init, &mac))
 610                         continue;
 611                 if(init != NULL){
 612                         eth_configure(index, init, mac, transport);
 613                         kfree(init);
 614                 }
 615                 found = 1;
 616                 break;
 617         }
 618
 619         spin_unlock(&transports_lock);
 620         return found;
 621 }
 622
 623 static int eth_setup(char *str)
 624 {
 625         struct eth_init *new;
 626         char *error;
 627         int n, err;
 628
 629         err = eth_parse(str, &n, &str, &error);
 630         if(err){
 631                 printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
 632                        str, error);
 633                 return 1;
 634         }
 635
 636         new = alloc_bootmem(sizeof(*new));
 637         if (new == NULL){
 638                 printk("eth_init : alloc_bootmem failed\n");
 639                 return 1;
 640         }
 641
 642         INIT_LIST_HEAD(&new->list);
 643         new->index = n;
 644         new->init = str;
 645
 646         list_add_tail(&new->list, &eth_cmd_line);
 647         return 1;
 648 }
 649
 650 __setup("eth", eth_setup);
 651 __uml_help(eth_setup,
 652 "eth[0-9]+=<transport>,<options>\n"
 653 "    Configure a network device.\n\n"
 654 );
 655
 656 static int net_config(char *str, char **error_out)
 657 {
 658         int n, err;
 659
 660         err = eth_parse(str, &n, &str, error_out);
 661         if(err)
 662                 return err;
 663
 664         /* This string is broken up and the pieces used by the underlying
 665          * driver.  So, it is freed only if eth_setup_common fails.
 666          */
 667         str = kstrdup(str, GFP_KERNEL);
 668         if(str == NULL){
 669                 *error_out = "net_config failed to strdup string";
 670                 return -ENOMEM;
 671         }
 672         err = !eth_setup_common(str, n);
 673         if(err)
 674                 kfree(str);
 675         return(err);
 676 }
 677
 678 static int net_id(char **str, int *start_out, int *end_out)
 679 {
 680         char *end;
 681         int n;
 682
 683         n = simple_strtoul(*str, &end, 0);
 684         if((*end != '\0') || (end == *str))
 685                 return -1;
 686
 687         *start_out = n;
 688         *end_out = n;
 689         *str = end;
 690         return n;
 691 }
 692
 693 static int net_remove(int n, char **error_out)
 694 {
 695         struct uml_net *device;
 696         struct net_device *dev;
 697         struct uml_net_private *lp;
 698
 699         device = find_device(n);
 700         if(device == NULL)
 701                 return -ENODEV;
 702
 703         dev = device->dev;
 704         lp = dev->priv;
 705         if(lp->fd > 0)
 706                 return -EBUSY;
 707         unregister_netdev(dev);
 708         platform_device_unregister(&device->pdev);
 709
 710         return 0;
 711 }
 712
 713 static struct mc_device net_mc = {
 714         .list           = LIST_HEAD_INIT(net_mc.list),
 715         .name           = "eth",
 716         .config         = net_config,
 717         .get_config     = NULL,
 718         .id             = net_id,
 719         .remove         = net_remove,
 720 };
 721
 722 static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
 723                               void *ptr)
 724 {
 725         struct in_ifaddr *ifa = ptr;
 726         struct net_device *dev = ifa->ifa_dev->dev;
 727         struct uml_net_private *lp;
 728         void (*proc)(unsigned char *, unsigned char *, void *);
 729         unsigned char addr_buf[4], netmask_buf[4];
 730
 731         if(dev->open != uml_net_open)
 732                 return NOTIFY_DONE;
 733
 734         lp = dev->priv;
 735
 736         proc = NULL;
 737         switch (event){
 738         case NETDEV_UP:
 739                 proc = lp->add_address;
 740                 break;
 741         case NETDEV_DOWN:
 742                 proc = lp->delete_address;
 743                 break;
 744         }
 745         if(proc != NULL){
 746                 memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
 747                 memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
 748                 (*proc)(addr_buf, netmask_buf, &lp->user);
 749         }
 750         return NOTIFY_DONE;
 751 }
 752
 753 /* uml_net_init shouldn't be called twice on two CPUs at the same time */
 754 struct notifier_block uml_inetaddr_notifier = {
 755         .notifier_call          = uml_inetaddr_event,
 756 };
 757
 758 static int uml_net_init(void)
 759 {
 760         struct list_head *ele;
 761         struct uml_net_private *lp;
 762         struct in_device *ip;
 763         struct in_ifaddr *in;
 764
 765         mconsole_register_dev(&net_mc);
 766         register_inetaddr_notifier(&uml_inetaddr_notifier);
 767
 768         /* Devices may have been opened already, so the uml_inetaddr_notifier
 769          * didn't get a chance to run for them.  This fakes it so that
 770          * addresses which have already been set up get handled properly.
 771          */
 772         spin_lock(&opened_lock);
 773         list_for_each(ele, &opened){
 774                 lp = list_entry(ele, struct uml_net_private, list);
 775                 ip = lp->dev->ip_ptr;
 776                 if(ip == NULL)
 777                         continue;
 778                 in = ip->ifa_list;
 779                 while(in != NULL){
 780                         uml_inetaddr_event(NULL, NETDEV_UP, in);
 781                         in = in->ifa_next;
 782                 }
 783         }
 784         spin_unlock(&opened_lock);
 785
 786         return 0;
 787 }
 788
 789 __initcall(uml_net_init);
 790
 791 static void close_devices(void)
 792 {
 793         struct list_head *ele;
 794         struct uml_net_private *lp;
 795
 796         spin_lock(&opened_lock);
 797         list_for_each(ele, &opened){
 798                 lp = list_entry(ele, struct uml_net_private, list);
 799                 free_irq(lp->dev->irq, lp->dev);
 800                 if((lp->close != NULL) && (lp->fd >= 0))
 801                         (*lp->close)(lp->fd, &lp->user);
 802                 if(lp->remove != NULL)
 803                         (*lp->remove)(&lp->user);
 804         }
 805         spin_unlock(&opened_lock);
 806 }
 807
 808 __uml_exitcall(close_devices);
 809
 810 struct sk_buff *ether_adjust_skb(struct sk_buff *skb, int extra)
 811 {
 812         if((skb != NULL) && (skb_tailroom(skb) < extra)){
 813                 struct sk_buff *skb2;
 814
 815                 skb2 = skb_copy_expand(skb, 0, extra, GFP_ATOMIC);
 816                 dev_kfree_skb(skb);
 817                 skb = skb2;
 818         }
 819         if(skb != NULL) skb_put(skb, extra);
 820         return(skb);
 821 }
 822
 823 void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
 824                                         void *),
 825                     void *arg)
 826 {
 827         struct net_device *dev = d;
 828         struct in_device *ip = dev->ip_ptr;
 829         struct in_ifaddr *in;
 830         unsigned char address[4], netmask[4];
 831
 832         if(ip == NULL) return;
 833         in = ip->ifa_list;
 834         while(in != NULL){
 835                 memcpy(address, &in->ifa_address, sizeof(address));
 836                 memcpy(netmask, &in->ifa_mask, sizeof(netmask));
 837                 (*cb)(address, netmask, arg);
 838                 in = in->ifa_next;
 839         }
 840 }
 841
 842 int dev_netmask(void *d, void *m)
 843 {
 844         struct net_device *dev = d;
 845         struct in_device *ip = dev->ip_ptr;
 846         struct in_ifaddr *in;
 847         __be32 *mask_out = m;
 848
 849         if(ip == NULL)
 850                 return(1);
 851
 852         in = ip->ifa_list;
 853         if(in == NULL)
 854                 return(1);
 855
 856         *mask_out = in->ifa_mask;
 857         return(0);
 858 }
 859
 860 void *get_output_buffer(int *len_out)
 861 {
 862         void *ret;
 863
 864         ret = (void *) __get_free_pages(GFP_KERNEL, 0);
 865         if(ret) *len_out = PAGE_SIZE;
 866         else *len_out = 0;
 867         return ret;
 868 }
 869
 870 void free_output_buffer(void *buffer)
 871 {
 872         free_pages((unsigned long) buffer, 0);
 873 }
 874
 875 int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
 876                      char **gate_addr)
 877 {
 878         char *remain;
 879
 880         remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
 881         if(remain != NULL){
 882                 printk("tap_setup_common - Extra garbage on specification : "
 883                        "'%s'\n", remain);
 884                 return(1);
 885         }
 886
 887         return(0);
 888 }
 889
 890 unsigned short eth_protocol(struct sk_buff *skb)
 891 {
 892         return(eth_type_trans(skb, skb->dev));
 893 }