drivers/net/macvlan.c

   1 /*
   2  * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of
   7  * the License, or (at your option) any later version.
   8  *
   9  * The code this is based on carried the following copyright notice:
  10  * ---
  11  * (C) Copyright 2001-2006
  12  * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
  13  * Re-worked by Ben Greear <greearb@candelatech.com>
  14  * ---
  15  */
  16 #include <linux/kernel.h>
  17 #include <linux/types.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/errno.h>
  21 #include <linux/slab.h>
  22 #include <linux/string.h>
  23 #include <linux/rculist.h>
  24 #include <linux/notifier.h>
  25 #include <linux/netdevice.h>
  26 #include <linux/etherdevice.h>
  27 #include <linux/ethtool.h>
  28 #include <linux/if_arp.h>
  29 #include <linux/if_link.h>
  30 #include <linux/if_macvlan.h>
  31 #include <net/rtnetlink.h>
  32 #include <net/xfrm.h>
  33
  34 #define MACVLAN_HASH_SIZE       (1 << BITS_PER_BYTE)
  35
  36 struct macvlan_port {
  37         struct net_device       *dev;
  38         struct hlist_head       vlan_hash[MACVLAN_HASH_SIZE];
  39         struct list_head        vlans;
  40         struct rcu_head         rcu;
  41         bool                    passthru;
  42         int                     count;
  43 };
  44
  45 static void macvlan_port_destroy(struct net_device *dev);
  46
  47 #define macvlan_port_get_rcu(dev) \
  48         ((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
  49 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
  50 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
  51
  52 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
  53                                                const unsigned char *addr)
  54 {
  55         struct macvlan_dev *vlan;
  56         struct hlist_node *n;
  57
  58         hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
  59                 if (!compare_ether_addr_64bits(vlan->dev->dev_addr, addr))
  60                         return vlan;
  61         }
  62         return NULL;
  63 }
  64
  65 static void macvlan_hash_add(struct macvlan_dev *vlan)
  66 {
  67         struct macvlan_port *port = vlan->port;
  68         const unsigned char *addr = vlan->dev->dev_addr;
  69
  70         hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
  71 }
  72
  73 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
  74 {
  75         hlist_del_rcu(&vlan->hlist);
  76         if (sync)
  77                 synchronize_rcu();
  78 }
  79
  80 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
  81                                         const unsigned char *addr)
  82 {
  83         macvlan_hash_del(vlan, true);
  84         /* Now that we are unhashed it is safe to change the device
  85          * address without confusing packet delivery.
  86          */
  87         memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
  88         macvlan_hash_add(vlan);
  89 }
  90
  91 static int macvlan_addr_busy(const struct macvlan_port *port,
  92                                 const unsigned char *addr)
  93 {
  94         /* Test to see if the specified multicast address is
  95          * currently in use by the underlying device or
  96          * another macvlan.
  97          */
  98         if (!compare_ether_addr_64bits(port->dev->dev_addr, addr))
  99                 return 1;
 100
 101         if (macvlan_hash_lookup(port, addr))
 102                 return 1;
 103
 104         return 0;
 105 }
 106
 107
 108 static int macvlan_broadcast_one(struct sk_buff *skb,
 109                                  const struct macvlan_dev *vlan,
 110                                  const struct ethhdr *eth, bool local)
 111 {
 112         struct net_device *dev = vlan->dev;
 113         if (!skb)
 114                 return NET_RX_DROP;
 115
 116         if (local)
 117                 return vlan->forward(dev, skb);
 118
 119         skb->dev = dev;
 120         if (!compare_ether_addr_64bits(eth->h_dest,
 121                                        dev->broadcast))
 122                 skb->pkt_type = PACKET_BROADCAST;
 123         else
 124                 skb->pkt_type = PACKET_MULTICAST;
 125
 126         return vlan->receive(skb);
 127 }
 128
 129 static void macvlan_broadcast(struct sk_buff *skb,
 130                               const struct macvlan_port *port,
 131                               struct net_device *src,
 132                               enum macvlan_mode mode)
 133 {
 134         const struct ethhdr *eth = eth_hdr(skb);
 135         const struct macvlan_dev *vlan;
 136         struct hlist_node *n;
 137         struct sk_buff *nskb;
 138         unsigned int i;
 139         int err;
 140
 141         if (skb->protocol == htons(ETH_P_PAUSE))
 142                 return;
 143
 144         for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
 145                 hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
 146                         if (vlan->dev == src || !(vlan->mode & mode))
 147                                 continue;
 148
 149                         nskb = skb_clone(skb, GFP_ATOMIC);
 150                         err = macvlan_broadcast_one(nskb, vlan, eth,
 151                                          mode == MACVLAN_MODE_BRIDGE);
 152                         macvlan_count_rx(vlan, skb->len + ETH_HLEN,
 153                                          err == NET_RX_SUCCESS, 1);
 154                 }
 155         }
 156 }
 157
 158 /* called under rcu_read_lock() from netif_receive_skb */
 159 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
 160 {
 161         struct macvlan_port *port;
 162         struct sk_buff *skb = *pskb;
 163         const struct ethhdr *eth = eth_hdr(skb);
 164         const struct macvlan_dev *vlan;
 165         const struct macvlan_dev *src;
 166         struct net_device *dev;
 167         unsigned int len = 0;
 168         int ret = NET_RX_DROP;
 169
 170         port = macvlan_port_get_rcu(skb->dev);
 171         if (is_multicast_ether_addr(eth->h_dest)) {
 172                 src = macvlan_hash_lookup(port, eth->h_source);
 173                 if (!src)
 174                         /* frame comes from an external address */
 175                         macvlan_broadcast(skb, port, NULL,
 176                                           MACVLAN_MODE_PRIVATE |
 177                                           MACVLAN_MODE_VEPA    |
 178                                           MACVLAN_MODE_PASSTHRU|
 179                                           MACVLAN_MODE_BRIDGE);
 180                 else if (src->mode == MACVLAN_MODE_VEPA)
 181                         /* flood to everyone except source */
 182                         macvlan_broadcast(skb, port, src->dev,
 183                                           MACVLAN_MODE_VEPA |
 184                                           MACVLAN_MODE_BRIDGE);
 185                 else if (src->mode == MACVLAN_MODE_BRIDGE)
 186                         /*
 187                          * flood only to VEPA ports, bridge ports
 188                          * already saw the frame on the way out.
 189                          */
 190                         macvlan_broadcast(skb, port, src->dev,
 191                                           MACVLAN_MODE_VEPA);
 192                 return RX_HANDLER_PASS;
 193         }
 194
 195         if (port->passthru)
 196                 vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
 197         else
 198                 vlan = macvlan_hash_lookup(port, eth->h_dest);
 199         if (vlan == NULL)
 200                 return RX_HANDLER_PASS;
 201
 202         dev = vlan->dev;
 203         if (unlikely(!(dev->flags & IFF_UP))) {
 204                 kfree_skb(skb);
 205                 return RX_HANDLER_CONSUMED;
 206         }
 207         len = skb->len + ETH_HLEN;
 208         skb = skb_share_check(skb, GFP_ATOMIC);
 209         if (!skb)
 210                 goto out;
 211
 212         skb->dev = dev;
 213         skb->pkt_type = PACKET_HOST;
 214
 215         ret = vlan->receive(skb);
 216
 217 out:
 218         macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
 219         return RX_HANDLER_CONSUMED;
 220 }
 221
 222 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
 223 {
 224         const struct macvlan_dev *vlan = netdev_priv(dev);
 225         const struct macvlan_port *port = vlan->port;
 226         const struct macvlan_dev *dest;
 227         __u8 ip_summed = skb->ip_summed;
 228
 229         if (vlan->mode == MACVLAN_MODE_BRIDGE) {
 230                 const struct ethhdr *eth = (void *)skb->data;
 231                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 232
 233                 /* send to other bridge ports directly */
 234                 if (is_multicast_ether_addr(eth->h_dest)) {
 235                         macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
 236                         goto xmit_world;
 237                 }
 238
 239                 dest = macvlan_hash_lookup(port, eth->h_dest);
 240                 if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
 241                         /* send to lowerdev first for its network taps */
 242                         vlan->forward(vlan->lowerdev, skb);
 243
 244                         return NET_XMIT_SUCCESS;
 245                 }
 246         }
 247
 248 xmit_world:
 249         skb->ip_summed = ip_summed;
 250         skb_set_dev(skb, vlan->lowerdev);
 251         return dev_queue_xmit(skb);
 252 }
 253
 254 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
 255                                struct net_device *dev)
 256 {
 257         unsigned int len = skb->len;
 258         int ret;
 259         const struct macvlan_dev *vlan = netdev_priv(dev);
 260
 261         ret = macvlan_queue_xmit(skb, dev);
 262         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 263                 struct macvlan_pcpu_stats *pcpu_stats;
 264
 265                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
 266                 u64_stats_update_begin(&pcpu_stats->syncp);
 267                 pcpu_stats->tx_packets++;
 268                 pcpu_stats->tx_bytes += len;
 269                 u64_stats_update_end(&pcpu_stats->syncp);
 270         } else {
 271                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
 272         }
 273         return ret;
 274 }
 275 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
 276
 277 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 278                                unsigned short type, const void *daddr,
 279                                const void *saddr, unsigned len)
 280 {
 281         const struct macvlan_dev *vlan = netdev_priv(dev);
 282         struct net_device *lowerdev = vlan->lowerdev;
 283
 284         return dev_hard_header(skb, lowerdev, type, daddr,
 285                                saddr ? : dev->dev_addr, len);
 286 }
 287
 288 static const struct header_ops macvlan_hard_header_ops = {
 289         .create         = macvlan_hard_header,
 290         .rebuild        = eth_rebuild_header,
 291         .parse          = eth_header_parse,
 292         .cache          = eth_header_cache,
 293         .cache_update   = eth_header_cache_update,
 294 };
 295
 296 static int macvlan_open(struct net_device *dev)
 297 {
 298         struct macvlan_dev *vlan = netdev_priv(dev);
 299         struct net_device *lowerdev = vlan->lowerdev;
 300         int err;
 301
 302         if (vlan->port->passthru) {
 303                 dev_set_promiscuity(lowerdev, 1);
 304                 goto hash_add;
 305         }
 306
 307         err = -EBUSY;
 308         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
 309                 goto out;
 310
 311         err = dev_uc_add(lowerdev, dev->dev_addr);
 312         if (err < 0)
 313                 goto out;
 314         if (dev->flags & IFF_ALLMULTI) {
 315                 err = dev_set_allmulti(lowerdev, 1);
 316                 if (err < 0)
 317                         goto del_unicast;
 318         }
 319
 320 hash_add:
 321         macvlan_hash_add(vlan);
 322         return 0;
 323
 324 del_unicast:
 325         dev_uc_del(lowerdev, dev->dev_addr);
 326 out:
 327         return err;
 328 }
 329
 330 static int macvlan_stop(struct net_device *dev)
 331 {
 332         struct macvlan_dev *vlan = netdev_priv(dev);
 333         struct net_device *lowerdev = vlan->lowerdev;
 334
 335         if (vlan->port->passthru) {
 336                 dev_set_promiscuity(lowerdev, -1);
 337                 goto hash_del;
 338         }
 339
 340         dev_mc_unsync(lowerdev, dev);
 341         if (dev->flags & IFF_ALLMULTI)
 342                 dev_set_allmulti(lowerdev, -1);
 343
 344         dev_uc_del(lowerdev, dev->dev_addr);
 345
 346 hash_del:
 347         macvlan_hash_del(vlan, !dev->dismantle);
 348         return 0;
 349 }
 350
 351 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 352 {
 353         struct macvlan_dev *vlan = netdev_priv(dev);
 354         struct net_device *lowerdev = vlan->lowerdev;
 355         struct sockaddr *addr = p;
 356         int err;
 357
 358         if (!is_valid_ether_addr(addr->sa_data))
 359                 return -EADDRNOTAVAIL;
 360
 361         if (!(dev->flags & IFF_UP)) {
 362                 /* Just copy in the new address */
 363                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 364         } else {
 365                 /* Rehash and update the device filters */
 366                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
 367                         return -EBUSY;
 368
 369                 err = dev_uc_add(lowerdev, addr->sa_data);
 370                 if (err)
 371                         return err;
 372
 373                 dev_uc_del(lowerdev, dev->dev_addr);
 374
 375                 macvlan_hash_change_addr(vlan, addr->sa_data);
 376         }
 377         return 0;
 378 }
 379
 380 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 381 {
 382         struct macvlan_dev *vlan = netdev_priv(dev);
 383         struct net_device *lowerdev = vlan->lowerdev;
 384
 385         if (change & IFF_ALLMULTI)
 386                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 387 }
 388
 389 static void macvlan_set_multicast_list(struct net_device *dev)
 390 {
 391         struct macvlan_dev *vlan = netdev_priv(dev);
 392
 393         dev_mc_sync(vlan->lowerdev, dev);
 394 }
 395
 396 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 397 {
 398         struct macvlan_dev *vlan = netdev_priv(dev);
 399
 400         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 401                 return -EINVAL;
 402         dev->mtu = new_mtu;
 403         return 0;
 404 }
 405
 406 /*
 407  * macvlan network devices have devices nesting below it and are a special
 408  * "super class" of normal network devices; split their locks off into a
 409  * separate class since they always nest.
 410  */
 411 static struct lock_class_key macvlan_netdev_xmit_lock_key;
 412 static struct lock_class_key macvlan_netdev_addr_lock_key;
 413
 414 #define MACVLAN_FEATURES \
 415         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 416          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 417          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM)
 418
 419 #define MACVLAN_STATE_MASK \
 420         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 421
 422 static void macvlan_set_lockdep_class_one(struct net_device *dev,
 423                                           struct netdev_queue *txq,
 424                                           void *_unused)
 425 {
 426         lockdep_set_class(&txq->_xmit_lock,
 427                           &macvlan_netdev_xmit_lock_key);
 428 }
 429
 430 static void macvlan_set_lockdep_class(struct net_device *dev)
 431 {
 432         lockdep_set_class(&dev->addr_list_lock,
 433                           &macvlan_netdev_addr_lock_key);
 434         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 435 }
 436
 437 static int macvlan_init(struct net_device *dev)
 438 {
 439         struct macvlan_dev *vlan = netdev_priv(dev);
 440         const struct net_device *lowerdev = vlan->lowerdev;
 441
 442         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
 443                                   (lowerdev->state & MACVLAN_STATE_MASK);
 444         dev->features           = lowerdev->features & MACVLAN_FEATURES;
 445         dev->features           |= NETIF_F_LLTX;
 446         dev->gso_max_size       = lowerdev->gso_max_size;
 447         dev->iflink             = lowerdev->ifindex;
 448         dev->hard_header_len    = lowerdev->hard_header_len;
 449
 450         macvlan_set_lockdep_class(dev);
 451
 452         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
 453         if (!vlan->pcpu_stats)
 454                 return -ENOMEM;
 455
 456         return 0;
 457 }
 458
 459 static void macvlan_uninit(struct net_device *dev)
 460 {
 461         struct macvlan_dev *vlan = netdev_priv(dev);
 462         struct macvlan_port *port = vlan->port;
 463
 464         free_percpu(vlan->pcpu_stats);
 465
 466         port->count -= 1;
 467         if (!port->count)
 468                 macvlan_port_destroy(port->dev);
 469 }
 470
 471 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
 472                                                          struct rtnl_link_stats64 *stats)
 473 {
 474         struct macvlan_dev *vlan = netdev_priv(dev);
 475
 476         if (vlan->pcpu_stats) {
 477                 struct macvlan_pcpu_stats *p;
 478                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
 479                 u32 rx_errors = 0, tx_dropped = 0;
 480                 unsigned int start;
 481                 int i;
 482
 483                 for_each_possible_cpu(i) {
 484                         p = per_cpu_ptr(vlan->pcpu_stats, i);
 485                         do {
 486                                 start = u64_stats_fetch_begin_bh(&p->syncp);
 487                                 rx_packets      = p->rx_packets;
 488                                 rx_bytes        = p->rx_bytes;
 489                                 rx_multicast    = p->rx_multicast;
 490                                 tx_packets      = p->tx_packets;
 491                                 tx_bytes        = p->tx_bytes;
 492                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
 493
 494                         stats->rx_packets       += rx_packets;
 495                         stats->rx_bytes         += rx_bytes;
 496                         stats->multicast        += rx_multicast;
 497                         stats->tx_packets       += tx_packets;
 498                         stats->tx_bytes         += tx_bytes;
 499                         /* rx_errors & tx_dropped are u32, updated
 500                          * without syncp protection.
 501                          */
 502                         rx_errors       += p->rx_errors;
 503                         tx_dropped      += p->tx_dropped;
 504                 }
 505                 stats->rx_errors        = rx_errors;
 506                 stats->rx_dropped       = rx_errors;
 507                 stats->tx_dropped       = tx_dropped;
 508         }
 509         return stats;
 510 }
 511
 512 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 513                                         struct ethtool_drvinfo *drvinfo)
 514 {
 515         snprintf(drvinfo->driver, 32, "macvlan");
 516         snprintf(drvinfo->version, 32, "0.1");
 517 }
 518
 519 static int macvlan_ethtool_get_settings(struct net_device *dev,
 520                                         struct ethtool_cmd *cmd)
 521 {
 522         const struct macvlan_dev *vlan = netdev_priv(dev);
 523         return dev_ethtool_get_settings(vlan->lowerdev, cmd);
 524 }
 525
 526 static const struct ethtool_ops macvlan_ethtool_ops = {
 527         .get_link               = ethtool_op_get_link,
 528         .get_settings           = macvlan_ethtool_get_settings,
 529         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
 530 };
 531
 532 static const struct net_device_ops macvlan_netdev_ops = {
 533         .ndo_init               = macvlan_init,
 534         .ndo_uninit             = macvlan_uninit,
 535         .ndo_open               = macvlan_open,
 536         .ndo_stop               = macvlan_stop,
 537         .ndo_start_xmit         = macvlan_start_xmit,
 538         .ndo_change_mtu         = macvlan_change_mtu,
 539         .ndo_change_rx_flags    = macvlan_change_rx_flags,
 540         .ndo_set_mac_address    = macvlan_set_mac_address,
 541         .ndo_set_multicast_list = macvlan_set_multicast_list,
 542         .ndo_get_stats64        = macvlan_dev_get_stats64,
 543         .ndo_validate_addr      = eth_validate_addr,
 544 };
 545
 546 void macvlan_common_setup(struct net_device *dev)
 547 {
 548         ether_setup(dev);
 549
 550         dev->priv_flags        &= ~IFF_XMIT_DST_RELEASE;
 551         dev->netdev_ops         = &macvlan_netdev_ops;
 552         dev->destructor         = free_netdev;
 553         dev->header_ops         = &macvlan_hard_header_ops,
 554         dev->ethtool_ops        = &macvlan_ethtool_ops;
 555 }
 556 EXPORT_SYMBOL_GPL(macvlan_common_setup);
 557
 558 static void macvlan_setup(struct net_device *dev)
 559 {
 560         macvlan_common_setup(dev);
 561         dev->tx_queue_len       = 0;
 562 }
 563
 564 static int macvlan_port_create(struct net_device *dev)
 565 {
 566         struct macvlan_port *port;
 567         unsigned int i;
 568         int err;
 569
 570         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 571                 return -EINVAL;
 572
 573         port = kzalloc(sizeof(*port), GFP_KERNEL);
 574         if (port == NULL)
 575                 return -ENOMEM;
 576
 577         port->passthru = false;
 578         port->dev = dev;
 579         INIT_LIST_HEAD(&port->vlans);
 580         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 581                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
 582
 583         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
 584         if (err)
 585                 kfree(port);
 586         else
 587                 dev->priv_flags |= IFF_MACVLAN_PORT;
 588         return err;
 589 }
 590
 591 static void macvlan_port_destroy(struct net_device *dev)
 592 {
 593         struct macvlan_port *port = macvlan_port_get(dev);
 594
 595         dev->priv_flags &= ~IFF_MACVLAN_PORT;
 596         netdev_rx_handler_unregister(dev);
 597         kfree_rcu(port, rcu);
 598 }
 599
 600 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 601 {
 602         if (tb[IFLA_ADDRESS]) {
 603                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 604                         return -EINVAL;
 605                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 606                         return -EADDRNOTAVAIL;
 607         }
 608
 609         if (data && data[IFLA_MACVLAN_MODE]) {
 610                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
 611                 case MACVLAN_MODE_PRIVATE:
 612                 case MACVLAN_MODE_VEPA:
 613                 case MACVLAN_MODE_BRIDGE:
 614                 case MACVLAN_MODE_PASSTHRU:
 615                         break;
 616                 default:
 617                         return -EINVAL;
 618                 }
 619         }
 620         return 0;
 621 }
 622
 623 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 624                            struct nlattr *tb[], struct nlattr *data[],
 625                            int (*receive)(struct sk_buff *skb),
 626                            int (*forward)(struct net_device *dev,
 627                                           struct sk_buff *skb))
 628 {
 629         struct macvlan_dev *vlan = netdev_priv(dev);
 630         struct macvlan_port *port;
 631         struct net_device *lowerdev;
 632         int err;
 633
 634         if (!tb[IFLA_LINK])
 635                 return -EINVAL;
 636
 637         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 638         if (lowerdev == NULL)
 639                 return -ENODEV;
 640
 641         /* When creating macvlans on top of other macvlans - use
 642          * the real device as the lowerdev.
 643          */
 644         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
 645                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
 646                 lowerdev = lowervlan->lowerdev;
 647         }
 648
 649         if (!tb[IFLA_MTU])
 650                 dev->mtu = lowerdev->mtu;
 651         else if (dev->mtu > lowerdev->mtu)
 652                 return -EINVAL;
 653
 654         if (!tb[IFLA_ADDRESS])
 655                 random_ether_addr(dev->dev_addr);
 656
 657         if (!macvlan_port_exists(lowerdev)) {
 658                 err = macvlan_port_create(lowerdev);
 659                 if (err < 0)
 660                         return err;
 661         }
 662         port = macvlan_port_get(lowerdev);
 663
 664         /* Only 1 macvlan device can be created in passthru mode */
 665         if (port->passthru)
 666                 return -EINVAL;
 667
 668         vlan->lowerdev = lowerdev;
 669         vlan->dev      = dev;
 670         vlan->port     = port;
 671         vlan->receive  = receive;
 672         vlan->forward  = forward;
 673
 674         vlan->mode     = MACVLAN_MODE_VEPA;
 675         if (data && data[IFLA_MACVLAN_MODE])
 676                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 677
 678         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 679                 if (port->count)
 680                         return -EINVAL;
 681                 port->passthru = true;
 682                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 683         }
 684
 685         port->count += 1;
 686         err = register_netdevice(dev);
 687         if (err < 0)
 688                 goto destroy_port;
 689
 690         list_add_tail(&vlan->list, &port->vlans);
 691         netif_stacked_transfer_operstate(lowerdev, dev);
 692
 693         return 0;
 694
 695 destroy_port:
 696         port->count -= 1;
 697         if (!port->count)
 698                 macvlan_port_destroy(lowerdev);
 699
 700         return err;
 701 }
 702 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
 703
 704 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
 705                            struct nlattr *tb[], struct nlattr *data[])
 706 {
 707         return macvlan_common_newlink(src_net, dev, tb, data,
 708                                       netif_rx,
 709                                       dev_forward_skb);
 710 }
 711
 712 void macvlan_dellink(struct net_device *dev, struct list_head *head)
 713 {
 714         struct macvlan_dev *vlan = netdev_priv(dev);
 715
 716         list_del(&vlan->list);
 717         unregister_netdevice_queue(dev, head);
 718 }
 719 EXPORT_SYMBOL_GPL(macvlan_dellink);
 720
 721 static int macvlan_changelink(struct net_device *dev,
 722                 struct nlattr *tb[], struct nlattr *data[])
 723 {
 724         struct macvlan_dev *vlan = netdev_priv(dev);
 725         if (data && data[IFLA_MACVLAN_MODE])
 726                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 727         return 0;
 728 }
 729
 730 static size_t macvlan_get_size(const struct net_device *dev)
 731 {
 732         return nla_total_size(4);
 733 }
 734
 735 static int macvlan_fill_info(struct sk_buff *skb,
 736                                 const struct net_device *dev)
 737 {
 738         struct macvlan_dev *vlan = netdev_priv(dev);
 739
 740         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
 741         return 0;
 742
 743 nla_put_failure:
 744         return -EMSGSIZE;
 745 }
 746
 747 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
 748         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
 749 };
 750
 751 int macvlan_link_register(struct rtnl_link_ops *ops)
 752 {
 753         /* common fields */
 754         ops->priv_size          = sizeof(struct macvlan_dev);
 755         ops->validate           = macvlan_validate;
 756         ops->maxtype            = IFLA_MACVLAN_MAX;
 757         ops->policy             = macvlan_policy;
 758         ops->changelink         = macvlan_changelink;
 759         ops->get_size           = macvlan_get_size;
 760         ops->fill_info          = macvlan_fill_info;
 761
 762         return rtnl_link_register(ops);
 763 };
 764 EXPORT_SYMBOL_GPL(macvlan_link_register);
 765
 766 static struct rtnl_link_ops macvlan_link_ops = {
 767         .kind           = "macvlan",
 768         .setup          = macvlan_setup,
 769         .newlink        = macvlan_newlink,
 770         .dellink        = macvlan_dellink,
 771 };
 772
 773 static int macvlan_device_event(struct notifier_block *unused,
 774                                 unsigned long event, void *ptr)
 775 {
 776         struct net_device *dev = ptr;
 777         struct macvlan_dev *vlan, *next;
 778         struct macvlan_port *port;
 779         LIST_HEAD(list_kill);
 780
 781         if (!macvlan_port_exists(dev))
 782                 return NOTIFY_DONE;
 783
 784         port = macvlan_port_get(dev);
 785
 786         switch (event) {
 787         case NETDEV_CHANGE:
 788                 list_for_each_entry(vlan, &port->vlans, list)
 789                         netif_stacked_transfer_operstate(vlan->lowerdev,
 790                                                          vlan->dev);
 791                 break;
 792         case NETDEV_FEAT_CHANGE:
 793                 list_for_each_entry(vlan, &port->vlans, list) {
 794                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
 795                         vlan->dev->gso_max_size = dev->gso_max_size;
 796                         netdev_features_change(vlan->dev);
 797                 }
 798                 break;
 799         case NETDEV_UNREGISTER:
 800                 /* twiddle thumbs on netns device moves */
 801                 if (dev->reg_state != NETREG_UNREGISTERING)
 802                         break;
 803
 804                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
 805                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
 806                 unregister_netdevice_many(&list_kill);
 807                 list_del(&list_kill);
 808                 break;
 809         case NETDEV_PRE_TYPE_CHANGE:
 810                 /* Forbid underlaying device to change its type. */
 811                 return NOTIFY_BAD;
 812         }
 813         return NOTIFY_DONE;
 814 }
 815
 816 static struct notifier_block macvlan_notifier_block __read_mostly = {
 817         .notifier_call  = macvlan_device_event,
 818 };
 819
 820 static int __init macvlan_init_module(void)
 821 {
 822         int err;
 823
 824         register_netdevice_notifier(&macvlan_notifier_block);
 825
 826         err = macvlan_link_register(&macvlan_link_ops);
 827         if (err < 0)
 828                 goto err1;
 829         return 0;
 830 err1:
 831         unregister_netdevice_notifier(&macvlan_notifier_block);
 832         return err;
 833 }
 834
 835 static void __exit macvlan_cleanup_module(void)
 836 {
 837         rtnl_link_unregister(&macvlan_link_ops);
 838         unregister_netdevice_notifier(&macvlan_notifier_block);
 839 }
 840
 841 module_init(macvlan_init_module);
 842 module_exit(macvlan_cleanup_module);
 843
 844 MODULE_LICENSE("GPL");
 845 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 846 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 847 MODULE_ALIAS_RTNL_LINK("macvlan");