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/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
  30 static DEFINE_SPINLOCK(opened_lock);
  31 static 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  */
  41 static DEFINE_SPINLOCK(drop_lock);
  42 static struct sk_buff *drop_skb;
  43 static int drop_max;
  44
  45 static 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;
  67 out:
  68         spin_unlock_irqrestore(&drop_lock, flags);
  69
  70         return err;
  71 }
  72
  73 static 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
 108 static 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
 115 static 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
 142 out:
 143         spin_unlock(&lp->lock);
 144         return IRQ_HANDLED;
 145 }
 146
 147 static 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_DISABLED | 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;
 185 out_close:
 186         if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
 187         lp->fd = -1;
 188 out:
 189         return err;
 190 }
 191
 192 static 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         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
 210 static 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
 247 static void uml_net_set_multicast_list(struct net_device *dev)
 248 {
 249         return;
 250 }
 251
 252 static void uml_net_tx_timeout(struct net_device *dev)
 253 {
 254         dev->trans_start = jiffies;
 255         netif_wake_queue(dev);
 256 }
 257
 258 static 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
 266 static 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
 274 static 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
 281 static const struct ethtool_ops uml_net_ethtool_ops = {
 282         .get_drvinfo    = uml_net_get_drvinfo,
 283         .get_link       = ethtool_op_get_link,
 284 };
 285
 286 static 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
 296 static void 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;
 338
 339 random:
 340         printk(KERN_INFO
 341                "Choosing a random ethernet address for device %s\n", name);
 342         random_ether_addr(addr);
 343 }
 344
 345 static DEFINE_SPINLOCK(devices_lock);
 346 static LIST_HEAD(devices);
 347
 348 static struct platform_driver uml_net_driver = {
 349         .driver = {
 350                 .name  = DRIVER_NAME,
 351         },
 352 };
 353
 354 static void net_device_release(struct device *dev)
 355 {
 356         struct uml_net *device = dev_get_drvdata(dev);
 357         struct net_device *netdev = device->dev;
 358         struct uml_net_private *lp = netdev_priv(netdev);
 359
 360         if (lp->remove != NULL)
 361                 (*lp->remove)(&lp->user);
 362         list_del(&device->list);
 363         kfree(device);
 364         free_netdev(netdev);
 365 }
 366
 367 static const struct net_device_ops uml_netdev_ops = {
 368         .ndo_open               = uml_net_open,
 369         .ndo_stop               = uml_net_close,
 370         .ndo_start_xmit         = uml_net_start_xmit,
 371         .ndo_set_rx_mode        = uml_net_set_multicast_list,
 372         .ndo_tx_timeout         = uml_net_tx_timeout,
 373         .ndo_set_mac_address    = eth_mac_addr,
 374         .ndo_change_mtu         = uml_net_change_mtu,
 375         .ndo_validate_addr      = eth_validate_addr,
 376 #ifdef CONFIG_NET_POLL_CONTROLLER
 377         .ndo_poll_controller = uml_net_poll_controller,
 378 #endif
 379 };
 380
 381 /*
 382  * Ensures that platform_driver_register is called only once by
 383  * eth_configure.  Will be set in an initcall.
 384  */
 385 static int driver_registered;
 386
 387 static void eth_configure(int n, void *init, char *mac,
 388                           struct transport *transport)
 389 {
 390         struct uml_net *device;
 391         struct net_device *dev;
 392         struct uml_net_private *lp;
 393         int err, size;
 394
 395         size = transport->private_size + sizeof(struct uml_net_private);
 396
 397         device = kzalloc(sizeof(*device), GFP_KERNEL);
 398         if (device == NULL) {
 399                 printk(KERN_ERR "eth_configure failed to allocate struct "
 400                        "uml_net\n");
 401                 return;
 402         }
 403
 404         dev = alloc_etherdev(size);
 405         if (dev == NULL) {
 406                 printk(KERN_ERR "eth_configure: failed to allocate struct "
 407                        "net_device for eth%d\n", n);
 408                 goto out_free_device;
 409         }
 410
 411         INIT_LIST_HEAD(&device->list);
 412         device->index = n;
 413
 414         /* If this name ends up conflicting with an existing registered
 415          * netdevice, that is OK, register_netdev{,ice}() will notice this
 416          * and fail.
 417          */
 418         snprintf(dev->name, sizeof(dev->name), "eth%d", n);
 419
 420         setup_etheraddr(mac, device->mac, dev->name);
 421
 422         printk(KERN_INFO "Netdevice %d (%pM) : ", n, device->mac);
 423
 424         lp = netdev_priv(dev);
 425         /* This points to the transport private data. It's still clear, but we
 426          * must memset it to 0 *now*. Let's help the drivers. */
 427         memset(lp, 0, size);
 428         INIT_WORK(&lp->work, uml_dev_close);
 429
 430         /* sysfs register */
 431         if (!driver_registered) {
 432                 platform_driver_register(&uml_net_driver);
 433                 driver_registered = 1;
 434         }
 435         device->pdev.id = n;
 436         device->pdev.name = DRIVER_NAME;
 437         device->pdev.dev.release = net_device_release;
 438         dev_set_drvdata(&device->pdev.dev, device);
 439         if (platform_device_register(&device->pdev))
 440                 goto out_free_netdev;
 441         SET_NETDEV_DEV(dev,&device->pdev.dev);
 442
 443         device->dev = dev;
 444
 445         /*
 446          * These just fill in a data structure, so there's no failure
 447          * to be worried about.
 448          */
 449         (*transport->kern->init)(dev, init);
 450
 451         *lp = ((struct uml_net_private)
 452                 { .list                 = LIST_HEAD_INIT(lp->list),
 453                   .dev                  = dev,
 454                   .fd                   = -1,
 455                   .mac                  = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
 456                   .max_packet           = transport->user->max_packet,
 457                   .protocol             = transport->kern->protocol,
 458                   .open                 = transport->user->open,
 459                   .close                = transport->user->close,
 460                   .remove               = transport->user->remove,
 461                   .read                 = transport->kern->read,
 462                   .write                = transport->kern->write,
 463                   .add_address          = transport->user->add_address,
 464                   .delete_address       = transport->user->delete_address });
 465
 466         init_timer(&lp->tl);
 467         spin_lock_init(&lp->lock);
 468         lp->tl.function = uml_net_user_timer_expire;
 469         memcpy(lp->mac, device->mac, sizeof(lp->mac));
 470
 471         if ((transport->user->init != NULL) &&
 472             ((*transport->user->init)(&lp->user, dev) != 0))
 473                 goto out_unregister;
 474
 475         /* don't use eth_mac_addr, it will not work here */
 476         memcpy(dev->dev_addr, device->mac, ETH_ALEN);
 477         dev->mtu = transport->user->mtu;
 478         dev->netdev_ops = &uml_netdev_ops;
 479         dev->ethtool_ops = &uml_net_ethtool_ops;
 480         dev->watchdog_timeo = (HZ >> 1);
 481         dev->irq = UM_ETH_IRQ;
 482
 483         err = update_drop_skb(lp->max_packet);
 484         if (err)
 485                 goto out_undo_user_init;
 486
 487         rtnl_lock();
 488         err = register_netdevice(dev);
 489         rtnl_unlock();
 490         if (err)
 491                 goto out_undo_user_init;
 492
 493         spin_lock(&devices_lock);
 494         list_add(&device->list, &devices);
 495         spin_unlock(&devices_lock);
 496
 497         return;
 498
 499 out_undo_user_init:
 500         if (transport->user->remove != NULL)
 501                 (*transport->user->remove)(&lp->user);
 502 out_unregister:
 503         platform_device_unregister(&device->pdev);
 504         return; /* platform_device_unregister frees dev and device */
 505 out_free_netdev:
 506         free_netdev(dev);
 507 out_free_device:
 508         kfree(device);
 509 }
 510
 511 static struct uml_net *find_device(int n)
 512 {
 513         struct uml_net *device;
 514         struct list_head *ele;
 515
 516         spin_lock(&devices_lock);
 517         list_for_each(ele, &devices) {
 518                 device = list_entry(ele, struct uml_net, list);
 519                 if (device->index == n)
 520                         goto out;
 521         }
 522         device = NULL;
 523  out:
 524         spin_unlock(&devices_lock);
 525         return device;
 526 }
 527
 528 static int eth_parse(char *str, int *index_out, char **str_out,
 529                      char **error_out)
 530 {
 531         char *end;
 532         int n, err = -EINVAL;
 533
 534         n = simple_strtoul(str, &end, 0);
 535         if (end == str) {
 536                 *error_out = "Bad device number";
 537                 return err;
 538         }
 539
 540         str = end;
 541         if (*str != '=') {
 542                 *error_out = "Expected '=' after device number";
 543                 return err;
 544         }
 545
 546         str++;
 547         if (find_device(n)) {
 548                 *error_out = "Device already configured";
 549                 return err;
 550         }
 551
 552         *index_out = n;
 553         *str_out = str;
 554         return 0;
 555 }
 556
 557 struct eth_init {
 558         struct list_head list;
 559         char *init;
 560         int index;
 561 };
 562
 563 static DEFINE_SPINLOCK(transports_lock);
 564 static LIST_HEAD(transports);
 565
 566 /* Filled in during early boot */
 567 static LIST_HEAD(eth_cmd_line);
 568
 569 static int check_transport(struct transport *transport, char *eth, int n,
 570                            void **init_out, char **mac_out)
 571 {
 572         int len;
 573
 574         len = strlen(transport->name);
 575         if (strncmp(eth, transport->name, len))
 576                 return 0;
 577
 578         eth += len;
 579         if (*eth == ',')
 580                 eth++;
 581         else if (*eth != '\0')
 582                 return 0;
 583
 584         *init_out = kmalloc(transport->setup_size, GFP_KERNEL);
 585         if (*init_out == NULL)
 586                 return 1;
 587
 588         if (!transport->setup(eth, mac_out, *init_out)) {
 589                 kfree(*init_out);
 590                 *init_out = NULL;
 591         }
 592         return 1;
 593 }
 594
 595 void register_transport(struct transport *new)
 596 {
 597         struct list_head *ele, *next;
 598         struct eth_init *eth;
 599         void *init;
 600         char *mac = NULL;
 601         int match;
 602
 603         spin_lock(&transports_lock);
 604         BUG_ON(!list_empty(&new->list));
 605         list_add(&new->list, &transports);
 606         spin_unlock(&transports_lock);
 607
 608         list_for_each_safe(ele, next, &eth_cmd_line) {
 609                 eth = list_entry(ele, struct eth_init, list);
 610                 match = check_transport(new, eth->init, eth->index, &init,
 611                                         &mac);
 612                 if (!match)
 613                         continue;
 614                 else if (init != NULL) {
 615                         eth_configure(eth->index, init, mac, new);
 616                         kfree(init);
 617                 }
 618                 list_del(&eth->list);
 619         }
 620 }
 621
 622 static int eth_setup_common(char *str, int index)
 623 {
 624         struct list_head *ele;
 625         struct transport *transport;
 626         void *init;
 627         char *mac = NULL;
 628         int found = 0;
 629
 630         spin_lock(&transports_lock);
 631         list_for_each(ele, &transports) {
 632                 transport = list_entry(ele, struct transport, list);
 633                 if (!check_transport(transport, str, index, &init, &mac))
 634                         continue;
 635                 if (init != NULL) {
 636                         eth_configure(index, init, mac, transport);
 637                         kfree(init);
 638                 }
 639                 found = 1;
 640                 break;
 641         }
 642
 643         spin_unlock(&transports_lock);
 644         return found;
 645 }
 646
 647 static int __init eth_setup(char *str)
 648 {
 649         struct eth_init *new;
 650         char *error;
 651         int n, err;
 652
 653         err = eth_parse(str, &n, &str, &error);
 654         if (err) {
 655                 printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
 656                        str, error);
 657                 return 1;
 658         }
 659
 660         new = alloc_bootmem(sizeof(*new));
 661         if (new == NULL) {
 662                 printk(KERN_ERR "eth_init : alloc_bootmem failed\n");
 663                 return 1;
 664         }
 665
 666         INIT_LIST_HEAD(&new->list);
 667         new->index = n;
 668         new->init = str;
 669
 670         list_add_tail(&new->list, &eth_cmd_line);
 671         return 1;
 672 }
 673
 674 __setup("eth", eth_setup);
 675 __uml_help(eth_setup,
 676 "eth[0-9]+=<transport>,<options>\n"
 677 "    Configure a network device.\n\n"
 678 );
 679
 680 static int net_config(char *str, char **error_out)
 681 {
 682         int n, err;
 683
 684         err = eth_parse(str, &n, &str, error_out);
 685         if (err)
 686                 return err;
 687
 688         /* This string is broken up and the pieces used by the underlying
 689          * driver.  So, it is freed only if eth_setup_common fails.
 690          */
 691         str = kstrdup(str, GFP_KERNEL);
 692         if (str == NULL) {
 693                 *error_out = "net_config failed to strdup string";
 694                 return -ENOMEM;
 695         }
 696         err = !eth_setup_common(str, n);
 697         if (err)
 698                 kfree(str);
 699         return err;
 700 }
 701
 702 static int net_id(char **str, int *start_out, int *end_out)
 703 {
 704         char *end;
 705         int n;
 706
 707         n = simple_strtoul(*str, &end, 0);
 708         if ((*end != '\0') || (end == *str))
 709                 return -1;
 710
 711         *start_out = n;
 712         *end_out = n;
 713         *str = end;
 714         return n;
 715 }
 716
 717 static int net_remove(int n, char **error_out)
 718 {
 719         struct uml_net *device;
 720         struct net_device *dev;
 721         struct uml_net_private *lp;
 722
 723         device = find_device(n);
 724         if (device == NULL)
 725                 return -ENODEV;
 726
 727         dev = device->dev;
 728         lp = netdev_priv(dev);
 729         if (lp->fd > 0)
 730                 return -EBUSY;
 731         unregister_netdev(dev);
 732         platform_device_unregister(&device->pdev);
 733
 734         return 0;
 735 }
 736
 737 static struct mc_device net_mc = {
 738         .list           = LIST_HEAD_INIT(net_mc.list),
 739         .name           = "eth",
 740         .config         = net_config,
 741         .get_config     = NULL,
 742         .id             = net_id,
 743         .remove         = net_remove,
 744 };
 745
 746 #ifdef CONFIG_INET
 747 static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
 748                               void *ptr)
 749 {
 750         struct in_ifaddr *ifa = ptr;
 751         struct net_device *dev = ifa->ifa_dev->dev;
 752         struct uml_net_private *lp;
 753         void (*proc)(unsigned char *, unsigned char *, void *);
 754         unsigned char addr_buf[4], netmask_buf[4];
 755
 756         if (dev->netdev_ops->ndo_open != uml_net_open)
 757                 return NOTIFY_DONE;
 758
 759         lp = netdev_priv(dev);
 760
 761         proc = NULL;
 762         switch (event) {
 763         case NETDEV_UP:
 764                 proc = lp->add_address;
 765                 break;
 766         case NETDEV_DOWN:
 767                 proc = lp->delete_address;
 768                 break;
 769         }
 770         if (proc != NULL) {
 771                 memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
 772                 memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
 773                 (*proc)(addr_buf, netmask_buf, &lp->user);
 774         }
 775         return NOTIFY_DONE;
 776 }
 777
 778 /* uml_net_init shouldn't be called twice on two CPUs at the same time */
 779 static struct notifier_block uml_inetaddr_notifier = {
 780         .notifier_call          = uml_inetaddr_event,
 781 };
 782
 783 static void inet_register(void)
 784 {
 785         struct list_head *ele;
 786         struct uml_net_private *lp;
 787         struct in_device *ip;
 788         struct in_ifaddr *in;
 789
 790         register_inetaddr_notifier(&uml_inetaddr_notifier);
 791
 792         /* Devices may have been opened already, so the uml_inetaddr_notifier
 793          * didn't get a chance to run for them.  This fakes it so that
 794          * addresses which have already been set up get handled properly.
 795          */
 796         spin_lock(&opened_lock);
 797         list_for_each(ele, &opened) {
 798                 lp = list_entry(ele, struct uml_net_private, list);
 799                 ip = lp->dev->ip_ptr;
 800                 if (ip == NULL)
 801                         continue;
 802                 in = ip->ifa_list;
 803                 while (in != NULL) {
 804                         uml_inetaddr_event(NULL, NETDEV_UP, in);
 805                         in = in->ifa_next;
 806                 }
 807         }
 808         spin_unlock(&opened_lock);
 809 }
 810 #else
 811 static inline void inet_register(void)
 812 {
 813 }
 814 #endif
 815
 816 static int uml_net_init(void)
 817 {
 818         mconsole_register_dev(&net_mc);
 819         inet_register();
 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 }