arch/um/drivers/net_kern.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   4  * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
   5  * James Leu (jleu@mindspring.net).
   6  * Copyright (C) 2001 by various other people who didn't put their name here.
   7  */
   8
   9 #include <linux/memblock.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 out:
 141         spin_unlock(&lp->lock);
 142         return IRQ_HANDLED;
 143 }
 144
 145 static int uml_net_open(struct net_device *dev)
 146 {
 147         struct uml_net_private *lp = netdev_priv(dev);
 148         int err;
 149
 150         if (lp->fd >= 0) {
 151                 err = -ENXIO;
 152                 goto out;
 153         }
 154
 155         lp->fd = (*lp->open)(&lp->user);
 156         if (lp->fd < 0) {
 157                 err = lp->fd;
 158                 goto out;
 159         }
 160
 161         err = um_request_irq(dev->irq, lp->fd, IRQ_READ, uml_net_interrupt,
 162                              IRQF_SHARED, dev->name, dev);
 163         if (err != 0) {
 164                 printk(KERN_ERR "uml_net_open: failed to get irq(%d)\n", err);
 165                 err = -ENETUNREACH;
 166                 goto out_close;
 167         }
 168
 169         netif_start_queue(dev);
 170
 171         /* clear buffer - it can happen that the host side of the interface
 172          * is full when we get here.  In this case, new data is never queued,
 173          * SIGIOs never arrive, and the net never works.
 174          */
 175         while ((err = uml_net_rx(dev)) > 0) ;
 176
 177         spin_lock(&opened_lock);
 178         list_add(&lp->list, &opened);
 179         spin_unlock(&opened_lock);
 180
 181         return 0;
 182 out_close:
 183         if (lp->close != NULL) (*lp->close)(lp->fd, &lp->user);
 184         lp->fd = -1;
 185 out:
 186         return err;
 187 }
 188
 189 static int uml_net_close(struct net_device *dev)
 190 {
 191         struct uml_net_private *lp = netdev_priv(dev);
 192
 193         netif_stop_queue(dev);
 194
 195         um_free_irq(dev->irq, dev);
 196         if (lp->close != NULL)
 197                 (*lp->close)(lp->fd, &lp->user);
 198         lp->fd = -1;
 199
 200         spin_lock(&opened_lock);
 201         list_del(&lp->list);
 202         spin_unlock(&opened_lock);
 203
 204         return 0;
 205 }
 206
 207 static netdev_tx_t uml_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
 208 {
 209         struct uml_net_private *lp = netdev_priv(dev);
 210         unsigned long flags;
 211         int len;
 212
 213         netif_stop_queue(dev);
 214
 215         spin_lock_irqsave(&lp->lock, flags);
 216
 217         len = (*lp->write)(lp->fd, skb, lp);
 218         skb_tx_timestamp(skb);
 219
 220         if (len == skb->len) {
 221                 dev->stats.tx_packets++;
 222                 dev->stats.tx_bytes += skb->len;
 223                 netif_trans_update(dev);
 224                 netif_start_queue(dev);
 225
 226                 /* this is normally done in the interrupt when tx finishes */
 227                 netif_wake_queue(dev);
 228         }
 229         else if (len == 0) {
 230                 netif_start_queue(dev);
 231                 dev->stats.tx_dropped++;
 232         }
 233         else {
 234                 netif_start_queue(dev);
 235                 printk(KERN_ERR "uml_net_start_xmit: failed(%d)\n", len);
 236         }
 237
 238         spin_unlock_irqrestore(&lp->lock, flags);
 239
 240         dev_consume_skb_any(skb);
 241
 242         return NETDEV_TX_OK;
 243 }
 244
 245 static void uml_net_set_multicast_list(struct net_device *dev)
 246 {
 247         return;
 248 }
 249
 250 static void uml_net_tx_timeout(struct net_device *dev)
 251 {
 252         netif_trans_update(dev);
 253         netif_wake_queue(dev);
 254 }
 255
 256 #ifdef CONFIG_NET_POLL_CONTROLLER
 257 static void uml_net_poll_controller(struct net_device *dev)
 258 {
 259         disable_irq(dev->irq);
 260         uml_net_interrupt(dev->irq, dev);
 261         enable_irq(dev->irq);
 262 }
 263 #endif
 264
 265 static void uml_net_get_drvinfo(struct net_device *dev,
 266                                 struct ethtool_drvinfo *info)
 267 {
 268         strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
 269         strlcpy(info->version, "42", sizeof(info->version));
 270 }
 271
 272 static const struct ethtool_ops uml_net_ethtool_ops = {
 273         .get_drvinfo    = uml_net_get_drvinfo,
 274         .get_link       = ethtool_op_get_link,
 275         .get_ts_info    = ethtool_op_get_ts_info,
 276 };
 277
 278 static void uml_net_user_timer_expire(struct timer_list *t)
 279 {
 280 #ifdef undef
 281         struct uml_net_private *lp = from_timer(lp, t, tl);
 282         struct connection *conn = &lp->user;
 283
 284         dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
 285         do_connect(conn);
 286 #endif
 287 }
 288
 289 void uml_net_setup_etheraddr(struct net_device *dev, char *str)
 290 {
 291         unsigned char *addr = dev->dev_addr;
 292         char *end;
 293         int i;
 294
 295         if (str == NULL)
 296                 goto random;
 297
 298         for (i = 0; i < 6; i++) {
 299                 addr[i] = simple_strtoul(str, &end, 16);
 300                 if ((end == str) ||
 301                    ((*end != ':') && (*end != ',') && (*end != '\0'))) {
 302                         printk(KERN_ERR
 303                                "setup_etheraddr: failed to parse '%s' "
 304                                "as an ethernet address\n", str);
 305                         goto random;
 306                 }
 307                 str = end + 1;
 308         }
 309         if (is_multicast_ether_addr(addr)) {
 310                 printk(KERN_ERR
 311                        "Attempt to assign a multicast ethernet address to a "
 312                        "device disallowed\n");
 313                 goto random;
 314         }
 315         if (!is_valid_ether_addr(addr)) {
 316                 printk(KERN_ERR
 317                        "Attempt to assign an invalid ethernet address to a "
 318                        "device disallowed\n");
 319                 goto random;
 320         }
 321         if (!is_local_ether_addr(addr)) {
 322                 printk(KERN_WARNING
 323                        "Warning: Assigning a globally valid ethernet "
 324                        "address to a device\n");
 325                 printk(KERN_WARNING "You should set the 2nd rightmost bit in "
 326                        "the first byte of the MAC,\n");
 327                 printk(KERN_WARNING "i.e. %02x:%02x:%02x:%02x:%02x:%02x\n",
 328                        addr[0] | 0x02, addr[1], addr[2], addr[3], addr[4],
 329                        addr[5]);
 330         }
 331         return;
 332
 333 random:
 334         printk(KERN_INFO
 335                "Choosing a random ethernet address for device %s\n", dev->name);
 336         eth_hw_addr_random(dev);
 337 }
 338
 339 static DEFINE_SPINLOCK(devices_lock);
 340 static LIST_HEAD(devices);
 341
 342 static struct platform_driver uml_net_driver = {
 343         .driver = {
 344                 .name  = DRIVER_NAME,
 345         },
 346 };
 347
 348 static void net_device_release(struct device *dev)
 349 {
 350         struct uml_net *device = dev_get_drvdata(dev);
 351         struct net_device *netdev = device->dev;
 352         struct uml_net_private *lp = netdev_priv(netdev);
 353
 354         if (lp->remove != NULL)
 355                 (*lp->remove)(&lp->user);
 356         list_del(&device->list);
 357         kfree(device);
 358         free_netdev(netdev);
 359 }
 360
 361 static const struct net_device_ops uml_netdev_ops = {
 362         .ndo_open               = uml_net_open,
 363         .ndo_stop               = uml_net_close,
 364         .ndo_start_xmit         = uml_net_start_xmit,
 365         .ndo_set_rx_mode        = uml_net_set_multicast_list,
 366         .ndo_tx_timeout         = uml_net_tx_timeout,
 367         .ndo_set_mac_address    = eth_mac_addr,
 368         .ndo_validate_addr      = eth_validate_addr,
 369 #ifdef CONFIG_NET_POLL_CONTROLLER
 370         .ndo_poll_controller = uml_net_poll_controller,
 371 #endif
 372 };
 373
 374 /*
 375  * Ensures that platform_driver_register is called only once by
 376  * eth_configure.  Will be set in an initcall.
 377  */
 378 static int driver_registered;
 379
 380 static void eth_configure(int n, void *init, char *mac,
 381                           struct transport *transport, gfp_t gfp_mask)
 382 {
 383         struct uml_net *device;
 384         struct net_device *dev;
 385         struct uml_net_private *lp;
 386         int err, size;
 387
 388         size = transport->private_size + sizeof(struct uml_net_private);
 389
 390         device = kzalloc(sizeof(*device), gfp_mask);
 391         if (device == NULL) {
 392                 printk(KERN_ERR "eth_configure failed to allocate struct "
 393                        "uml_net\n");
 394                 return;
 395         }
 396
 397         dev = alloc_etherdev(size);
 398         if (dev == NULL) {
 399                 printk(KERN_ERR "eth_configure: failed to allocate struct "
 400                        "net_device for eth%d\n", n);
 401                 goto out_free_device;
 402         }
 403
 404         INIT_LIST_HEAD(&device->list);
 405         device->index = n;
 406
 407         /* If this name ends up conflicting with an existing registered
 408          * netdevice, that is OK, register_netdev{,ice}() will notice this
 409          * and fail.
 410          */
 411         snprintf(dev->name, sizeof(dev->name), "eth%d", n);
 412
 413         uml_net_setup_etheraddr(dev, mac);
 414
 415         printk(KERN_INFO "Netdevice %d (%pM) : ", n, dev->dev_addr);
 416
 417         lp = netdev_priv(dev);
 418         /* This points to the transport private data. It's still clear, but we
 419          * must memset it to 0 *now*. Let's help the drivers. */
 420         memset(lp, 0, size);
 421         INIT_WORK(&lp->work, uml_dev_close);
 422
 423         /* sysfs register */
 424         if (!driver_registered) {
 425                 platform_driver_register(&uml_net_driver);
 426                 driver_registered = 1;
 427         }
 428         device->pdev.id = n;
 429         device->pdev.name = DRIVER_NAME;
 430         device->pdev.dev.release = net_device_release;
 431         dev_set_drvdata(&device->pdev.dev, device);
 432         if (platform_device_register(&device->pdev))
 433                 goto out_free_netdev;
 434         SET_NETDEV_DEV(dev,&device->pdev.dev);
 435
 436         device->dev = dev;
 437
 438         /*
 439          * These just fill in a data structure, so there's no failure
 440          * to be worried about.
 441          */
 442         (*transport->kern->init)(dev, init);
 443
 444         *lp = ((struct uml_net_private)
 445                 { .list                 = LIST_HEAD_INIT(lp->list),
 446                   .dev                  = dev,
 447                   .fd                   = -1,
 448                   .mac                  = { 0xfe, 0xfd, 0x0, 0x0, 0x0, 0x0},
 449                   .max_packet           = transport->user->max_packet,
 450                   .protocol             = transport->kern->protocol,
 451                   .open                 = transport->user->open,
 452                   .close                = transport->user->close,
 453                   .remove               = transport->user->remove,
 454                   .read                 = transport->kern->read,
 455                   .write                = transport->kern->write,
 456                   .add_address          = transport->user->add_address,
 457                   .delete_address       = transport->user->delete_address });
 458
 459         timer_setup(&lp->tl, uml_net_user_timer_expire, 0);
 460         spin_lock_init(&lp->lock);
 461         memcpy(lp->mac, dev->dev_addr, sizeof(lp->mac));
 462
 463         if ((transport->user->init != NULL) &&
 464             ((*transport->user->init)(&lp->user, dev) != 0))
 465                 goto out_unregister;
 466
 467         dev->mtu = transport->user->mtu;
 468         dev->netdev_ops = &uml_netdev_ops;
 469         dev->ethtool_ops = &uml_net_ethtool_ops;
 470         dev->watchdog_timeo = (HZ >> 1);
 471         dev->irq = UM_ETH_IRQ;
 472
 473         err = update_drop_skb(lp->max_packet);
 474         if (err)
 475                 goto out_undo_user_init;
 476
 477         rtnl_lock();
 478         err = register_netdevice(dev);
 479         rtnl_unlock();
 480         if (err)
 481                 goto out_undo_user_init;
 482
 483         spin_lock(&devices_lock);
 484         list_add(&device->list, &devices);
 485         spin_unlock(&devices_lock);
 486
 487         return;
 488
 489 out_undo_user_init:
 490         if (transport->user->remove != NULL)
 491                 (*transport->user->remove)(&lp->user);
 492 out_unregister:
 493         platform_device_unregister(&device->pdev);
 494         return; /* platform_device_unregister frees dev and device */
 495 out_free_netdev:
 496         free_netdev(dev);
 497 out_free_device:
 498         kfree(device);
 499 }
 500
 501 static struct uml_net *find_device(int n)
 502 {
 503         struct uml_net *device;
 504         struct list_head *ele;
 505
 506         spin_lock(&devices_lock);
 507         list_for_each(ele, &devices) {
 508                 device = list_entry(ele, struct uml_net, list);
 509                 if (device->index == n)
 510                         goto out;
 511         }
 512         device = NULL;
 513  out:
 514         spin_unlock(&devices_lock);
 515         return device;
 516 }
 517
 518 static int eth_parse(char *str, int *index_out, char **str_out,
 519                      char **error_out)
 520 {
 521         char *end;
 522         int n, err = -EINVAL;
 523
 524         n = simple_strtoul(str, &end, 0);
 525         if (end == str) {
 526                 *error_out = "Bad device number";
 527                 return err;
 528         }
 529
 530         str = end;
 531         if (*str != '=') {
 532                 *error_out = "Expected '=' after device number";
 533                 return err;
 534         }
 535
 536         str++;
 537         if (find_device(n)) {
 538                 *error_out = "Device already configured";
 539                 return err;
 540         }
 541
 542         *index_out = n;
 543         *str_out = str;
 544         return 0;
 545 }
 546
 547 struct eth_init {
 548         struct list_head list;
 549         char *init;
 550         int index;
 551 };
 552
 553 static DEFINE_SPINLOCK(transports_lock);
 554 static LIST_HEAD(transports);
 555
 556 /* Filled in during early boot */
 557 static LIST_HEAD(eth_cmd_line);
 558
 559 static int check_transport(struct transport *transport, char *eth, int n,
 560                            void **init_out, char **mac_out, gfp_t gfp_mask)
 561 {
 562         int len;
 563
 564         len = strlen(transport->name);
 565         if (strncmp(eth, transport->name, len))
 566                 return 0;
 567
 568         eth += len;
 569         if (*eth == ',')
 570                 eth++;
 571         else if (*eth != '\0')
 572                 return 0;
 573
 574         *init_out = kmalloc(transport->setup_size, gfp_mask);
 575         if (*init_out == NULL)
 576                 return 1;
 577
 578         if (!transport->setup(eth, mac_out, *init_out)) {
 579                 kfree(*init_out);
 580                 *init_out = NULL;
 581         }
 582         return 1;
 583 }
 584
 585 void register_transport(struct transport *new)
 586 {
 587         struct list_head *ele, *next;
 588         struct eth_init *eth;
 589         void *init;
 590         char *mac = NULL;
 591         int match;
 592
 593         spin_lock(&transports_lock);
 594         BUG_ON(!list_empty(&new->list));
 595         list_add(&new->list, &transports);
 596         spin_unlock(&transports_lock);
 597
 598         list_for_each_safe(ele, next, &eth_cmd_line) {
 599                 eth = list_entry(ele, struct eth_init, list);
 600                 match = check_transport(new, eth->init, eth->index, &init,
 601                                         &mac, GFP_KERNEL);
 602                 if (!match)
 603                         continue;
 604                 else if (init != NULL) {
 605                         eth_configure(eth->index, init, mac, new, GFP_KERNEL);
 606                         kfree(init);
 607                 }
 608                 list_del(&eth->list);
 609         }
 610 }
 611
 612 static int eth_setup_common(char *str, int index)
 613 {
 614         struct list_head *ele;
 615         struct transport *transport;
 616         void *init;
 617         char *mac = NULL;
 618         int found = 0;
 619
 620         spin_lock(&transports_lock);
 621         list_for_each(ele, &transports) {
 622                 transport = list_entry(ele, struct transport, list);
 623                 if (!check_transport(transport, str, index, &init,
 624                                         &mac, GFP_ATOMIC))
 625                         continue;
 626                 if (init != NULL) {
 627                         eth_configure(index, init, mac, transport, GFP_ATOMIC);
 628                         kfree(init);
 629                 }
 630                 found = 1;
 631                 break;
 632         }
 633
 634         spin_unlock(&transports_lock);
 635         return found;
 636 }
 637
 638 static int __init eth_setup(char *str)
 639 {
 640         struct eth_init *new;
 641         char *error;
 642         int n, err;
 643
 644         err = eth_parse(str, &n, &str, &error);
 645         if (err) {
 646                 printk(KERN_ERR "eth_setup - Couldn't parse '%s' : %s\n",
 647                        str, error);
 648                 return 1;
 649         }
 650
 651         new = memblock_alloc(sizeof(*new), SMP_CACHE_BYTES);
 652         if (!new)
 653                 panic("%s: Failed to allocate %zu bytes\n", __func__,
 654                       sizeof(*new));
 655
 656         INIT_LIST_HEAD(&new->list);
 657         new->index = n;
 658         new->init = str;
 659
 660         list_add_tail(&new->list, &eth_cmd_line);
 661         return 1;
 662 }
 663
 664 __setup("eth", eth_setup);
 665 __uml_help(eth_setup,
 666 "eth[0-9]+=<transport>,<options>\n"
 667 "    Configure a network device.\n\n"
 668 );
 669
 670 static int net_config(char *str, char **error_out)
 671 {
 672         int n, err;
 673
 674         err = eth_parse(str, &n, &str, error_out);
 675         if (err)
 676                 return err;
 677
 678         /* This string is broken up and the pieces used by the underlying
 679          * driver.  So, it is freed only if eth_setup_common fails.
 680          */
 681         str = kstrdup(str, GFP_KERNEL);
 682         if (str == NULL) {
 683                 *error_out = "net_config failed to strdup string";
 684                 return -ENOMEM;
 685         }
 686         err = !eth_setup_common(str, n);
 687         if (err)
 688                 kfree(str);
 689         return err;
 690 }
 691
 692 static int net_id(char **str, int *start_out, int *end_out)
 693 {
 694         char *end;
 695         int n;
 696
 697         n = simple_strtoul(*str, &end, 0);
 698         if ((*end != '\0') || (end == *str))
 699                 return -1;
 700
 701         *start_out = n;
 702         *end_out = n;
 703         *str = end;
 704         return n;
 705 }
 706
 707 static int net_remove(int n, char **error_out)
 708 {
 709         struct uml_net *device;
 710         struct net_device *dev;
 711         struct uml_net_private *lp;
 712
 713         device = find_device(n);
 714         if (device == NULL)
 715                 return -ENODEV;
 716
 717         dev = device->dev;
 718         lp = netdev_priv(dev);
 719         if (lp->fd > 0)
 720                 return -EBUSY;
 721         unregister_netdev(dev);
 722         platform_device_unregister(&device->pdev);
 723
 724         return 0;
 725 }
 726
 727 static struct mc_device net_mc = {
 728         .list           = LIST_HEAD_INIT(net_mc.list),
 729         .name           = "eth",
 730         .config         = net_config,
 731         .get_config     = NULL,
 732         .id             = net_id,
 733         .remove         = net_remove,
 734 };
 735
 736 #ifdef CONFIG_INET
 737 static int uml_inetaddr_event(struct notifier_block *this, unsigned long event,
 738                               void *ptr)
 739 {
 740         struct in_ifaddr *ifa = ptr;
 741         struct net_device *dev = ifa->ifa_dev->dev;
 742         struct uml_net_private *lp;
 743         void (*proc)(unsigned char *, unsigned char *, void *);
 744         unsigned char addr_buf[4], netmask_buf[4];
 745
 746         if (dev->netdev_ops->ndo_open != uml_net_open)
 747                 return NOTIFY_DONE;
 748
 749         lp = netdev_priv(dev);
 750
 751         proc = NULL;
 752         switch (event) {
 753         case NETDEV_UP:
 754                 proc = lp->add_address;
 755                 break;
 756         case NETDEV_DOWN:
 757                 proc = lp->delete_address;
 758                 break;
 759         }
 760         if (proc != NULL) {
 761                 memcpy(addr_buf, &ifa->ifa_address, sizeof(addr_buf));
 762                 memcpy(netmask_buf, &ifa->ifa_mask, sizeof(netmask_buf));
 763                 (*proc)(addr_buf, netmask_buf, &lp->user);
 764         }
 765         return NOTIFY_DONE;
 766 }
 767
 768 /* uml_net_init shouldn't be called twice on two CPUs at the same time */
 769 static struct notifier_block uml_inetaddr_notifier = {
 770         .notifier_call          = uml_inetaddr_event,
 771 };
 772
 773 static void inet_register(void)
 774 {
 775         struct list_head *ele;
 776         struct uml_net_private *lp;
 777         struct in_device *ip;
 778         struct in_ifaddr *in;
 779
 780         register_inetaddr_notifier(&uml_inetaddr_notifier);
 781
 782         /* Devices may have been opened already, so the uml_inetaddr_notifier
 783          * didn't get a chance to run for them.  This fakes it so that
 784          * addresses which have already been set up get handled properly.
 785          */
 786         spin_lock(&opened_lock);
 787         list_for_each(ele, &opened) {
 788                 lp = list_entry(ele, struct uml_net_private, list);
 789                 ip = lp->dev->ip_ptr;
 790                 if (ip == NULL)
 791                         continue;
 792                 in = ip->ifa_list;
 793                 while (in != NULL) {
 794                         uml_inetaddr_event(NULL, NETDEV_UP, in);
 795                         in = in->ifa_next;
 796                 }
 797         }
 798         spin_unlock(&opened_lock);
 799 }
 800 #else
 801 static inline void inet_register(void)
 802 {
 803 }
 804 #endif
 805
 806 static int uml_net_init(void)
 807 {
 808         mconsole_register_dev(&net_mc);
 809         inet_register();
 810         return 0;
 811 }
 812
 813 __initcall(uml_net_init);
 814
 815 static void close_devices(void)
 816 {
 817         struct list_head *ele;
 818         struct uml_net_private *lp;
 819
 820         spin_lock(&opened_lock);
 821         list_for_each(ele, &opened) {
 822                 lp = list_entry(ele, struct uml_net_private, list);
 823                 um_free_irq(lp->dev->irq, lp->dev);
 824                 if ((lp->close != NULL) && (lp->fd >= 0))
 825                         (*lp->close)(lp->fd, &lp->user);
 826                 if (lp->remove != NULL)
 827                         (*lp->remove)(&lp->user);
 828         }
 829         spin_unlock(&opened_lock);
 830 }
 831
 832 __uml_exitcall(close_devices);
 833
 834 void iter_addresses(void *d, void (*cb)(unsigned char *, unsigned char *,
 835                                         void *),
 836                     void *arg)
 837 {
 838         struct net_device *dev = d;
 839         struct in_device *ip = dev->ip_ptr;
 840         struct in_ifaddr *in;
 841         unsigned char address[4], netmask[4];
 842
 843         if (ip == NULL) return;
 844         in = ip->ifa_list;
 845         while (in != NULL) {
 846                 memcpy(address, &in->ifa_address, sizeof(address));
 847                 memcpy(netmask, &in->ifa_mask, sizeof(netmask));
 848                 (*cb)(address, netmask, arg);
 849                 in = in->ifa_next;
 850         }
 851 }
 852
 853 int dev_netmask(void *d, void *m)
 854 {
 855         struct net_device *dev = d;
 856         struct in_device *ip = dev->ip_ptr;
 857         struct in_ifaddr *in;
 858         __be32 *mask_out = m;
 859
 860         if (ip == NULL)
 861                 return 1;
 862
 863         in = ip->ifa_list;
 864         if (in == NULL)
 865                 return 1;
 866
 867         *mask_out = in->ifa_mask;
 868         return 0;
 869 }
 870
 871 void *get_output_buffer(int *len_out)
 872 {
 873         void *ret;
 874
 875         ret = (void *) __get_free_pages(GFP_KERNEL, 0);
 876         if (ret) *len_out = PAGE_SIZE;
 877         else *len_out = 0;
 878         return ret;
 879 }
 880
 881 void free_output_buffer(void *buffer)
 882 {
 883         free_pages((unsigned long) buffer, 0);
 884 }
 885
 886 int tap_setup_common(char *str, char *type, char **dev_name, char **mac_out,
 887                      char **gate_addr)
 888 {
 889         char *remain;
 890
 891         remain = split_if_spec(str, dev_name, mac_out, gate_addr, NULL);
 892         if (remain != NULL) {
 893                 printk(KERN_ERR "tap_setup_common - Extra garbage on "
 894                        "specification : '%s'\n", remain);
 895                 return 1;
 896         }
 897
 898         return 0;
 899 }
 900
 901 unsigned short eth_protocol(struct sk_buff *skb)
 902 {
 903         return eth_type_trans(skb, skb->dev);
 904 }