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                         unsigned int length = skb->len + ETH_HLEN;
 242                         int ret = dest->forward(dest->dev, skb);
 243                         macvlan_count_rx(dest, length,
 244                                          ret == NET_RX_SUCCESS, 0);
 245
 246                         return NET_XMIT_SUCCESS;
 247                 }
 248         }
 249
 250 xmit_world:
 251         skb->ip_summed = ip_summed;
 252         skb_set_dev(skb, vlan->lowerdev);
 253         return dev_queue_xmit(skb);
 254 }
 255
 256 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
 257                                struct net_device *dev)
 258 {
 259         unsigned int len = skb->len;
 260         int ret;
 261         const struct macvlan_dev *vlan = netdev_priv(dev);
 262
 263         ret = macvlan_queue_xmit(skb, dev);
 264         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 265                 struct macvlan_pcpu_stats *pcpu_stats;
 266
 267                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
 268                 u64_stats_update_begin(&pcpu_stats->syncp);
 269                 pcpu_stats->tx_packets++;
 270                 pcpu_stats->tx_bytes += len;
 271                 u64_stats_update_end(&pcpu_stats->syncp);
 272         } else {
 273                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
 274         }
 275         return ret;
 276 }
 277 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
 278
 279 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 280                                unsigned short type, const void *daddr,
 281                                const void *saddr, unsigned len)
 282 {
 283         const struct macvlan_dev *vlan = netdev_priv(dev);
 284         struct net_device *lowerdev = vlan->lowerdev;
 285
 286         return dev_hard_header(skb, lowerdev, type, daddr,
 287                                saddr ? : dev->dev_addr, len);
 288 }
 289
 290 static const struct header_ops macvlan_hard_header_ops = {
 291         .create         = macvlan_hard_header,
 292         .rebuild        = eth_rebuild_header,
 293         .parse          = eth_header_parse,
 294         .cache          = eth_header_cache,
 295         .cache_update   = eth_header_cache_update,
 296 };
 297
 298 static int macvlan_open(struct net_device *dev)
 299 {
 300         struct macvlan_dev *vlan = netdev_priv(dev);
 301         struct net_device *lowerdev = vlan->lowerdev;
 302         int err;
 303
 304         if (vlan->port->passthru) {
 305                 dev_set_promiscuity(lowerdev, 1);
 306                 goto hash_add;
 307         }
 308
 309         err = -EBUSY;
 310         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
 311                 goto out;
 312
 313         err = dev_uc_add(lowerdev, dev->dev_addr);
 314         if (err < 0)
 315                 goto out;
 316         if (dev->flags & IFF_ALLMULTI) {
 317                 err = dev_set_allmulti(lowerdev, 1);
 318                 if (err < 0)
 319                         goto del_unicast;
 320         }
 321
 322 hash_add:
 323         macvlan_hash_add(vlan);
 324         return 0;
 325
 326 del_unicast:
 327         dev_uc_del(lowerdev, dev->dev_addr);
 328 out:
 329         return err;
 330 }
 331
 332 static int macvlan_stop(struct net_device *dev)
 333 {
 334         struct macvlan_dev *vlan = netdev_priv(dev);
 335         struct net_device *lowerdev = vlan->lowerdev;
 336
 337         if (vlan->port->passthru) {
 338                 dev_set_promiscuity(lowerdev, -1);
 339                 goto hash_del;
 340         }
 341
 342         dev_mc_unsync(lowerdev, dev);
 343         if (dev->flags & IFF_ALLMULTI)
 344                 dev_set_allmulti(lowerdev, -1);
 345
 346         dev_uc_del(lowerdev, dev->dev_addr);
 347
 348 hash_del:
 349         macvlan_hash_del(vlan, !dev->dismantle);
 350         return 0;
 351 }
 352
 353 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 354 {
 355         struct macvlan_dev *vlan = netdev_priv(dev);
 356         struct net_device *lowerdev = vlan->lowerdev;
 357         struct sockaddr *addr = p;
 358         int err;
 359
 360         if (!is_valid_ether_addr(addr->sa_data))
 361                 return -EADDRNOTAVAIL;
 362
 363         if (!(dev->flags & IFF_UP)) {
 364                 /* Just copy in the new address */
 365                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 366         } else {
 367                 /* Rehash and update the device filters */
 368                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
 369                         return -EBUSY;
 370
 371                 err = dev_uc_add(lowerdev, addr->sa_data);
 372                 if (err)
 373                         return err;
 374
 375                 dev_uc_del(lowerdev, dev->dev_addr);
 376
 377                 macvlan_hash_change_addr(vlan, addr->sa_data);
 378         }
 379         return 0;
 380 }
 381
 382 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 383 {
 384         struct macvlan_dev *vlan = netdev_priv(dev);
 385         struct net_device *lowerdev = vlan->lowerdev;
 386
 387         if (change & IFF_ALLMULTI)
 388                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 389 }
 390
 391 static void macvlan_set_multicast_list(struct net_device *dev)
 392 {
 393         struct macvlan_dev *vlan = netdev_priv(dev);
 394
 395         dev_mc_sync(vlan->lowerdev, dev);
 396 }
 397
 398 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 399 {
 400         struct macvlan_dev *vlan = netdev_priv(dev);
 401
 402         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 403                 return -EINVAL;
 404         dev->mtu = new_mtu;
 405         return 0;
 406 }
 407
 408 /*
 409  * macvlan network devices have devices nesting below it and are a special
 410  * "super class" of normal network devices; split their locks off into a
 411  * separate class since they always nest.
 412  */
 413 static struct lock_class_key macvlan_netdev_xmit_lock_key;
 414 static struct lock_class_key macvlan_netdev_addr_lock_key;
 415
 416 #define MACVLAN_FEATURES \
 417         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 418          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 419          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM)
 420
 421 #define MACVLAN_STATE_MASK \
 422         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 423
 424 static void macvlan_set_lockdep_class_one(struct net_device *dev,
 425                                           struct netdev_queue *txq,
 426                                           void *_unused)
 427 {
 428         lockdep_set_class(&txq->_xmit_lock,
 429                           &macvlan_netdev_xmit_lock_key);
 430 }
 431
 432 static void macvlan_set_lockdep_class(struct net_device *dev)
 433 {
 434         lockdep_set_class(&dev->addr_list_lock,
 435                           &macvlan_netdev_addr_lock_key);
 436         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 437 }
 438
 439 static int macvlan_init(struct net_device *dev)
 440 {
 441         struct macvlan_dev *vlan = netdev_priv(dev);
 442         const struct net_device *lowerdev = vlan->lowerdev;
 443
 444         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
 445                                   (lowerdev->state & MACVLAN_STATE_MASK);
 446         dev->features           = lowerdev->features & MACVLAN_FEATURES;
 447         dev->features           |= NETIF_F_LLTX;
 448         dev->gso_max_size       = lowerdev->gso_max_size;
 449         dev->iflink             = lowerdev->ifindex;
 450         dev->hard_header_len    = lowerdev->hard_header_len;
 451
 452         macvlan_set_lockdep_class(dev);
 453
 454         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
 455         if (!vlan->pcpu_stats)
 456                 return -ENOMEM;
 457
 458         return 0;
 459 }
 460
 461 static void macvlan_uninit(struct net_device *dev)
 462 {
 463         struct macvlan_dev *vlan = netdev_priv(dev);
 464         struct macvlan_port *port = vlan->port;
 465
 466         free_percpu(vlan->pcpu_stats);
 467
 468         port->count -= 1;
 469         if (!port->count)
 470                 macvlan_port_destroy(port->dev);
 471 }
 472
 473 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
 474                                                          struct rtnl_link_stats64 *stats)
 475 {
 476         struct macvlan_dev *vlan = netdev_priv(dev);
 477
 478         if (vlan->pcpu_stats) {
 479                 struct macvlan_pcpu_stats *p;
 480                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
 481                 u32 rx_errors = 0, tx_dropped = 0;
 482                 unsigned int start;
 483                 int i;
 484
 485                 for_each_possible_cpu(i) {
 486                         p = per_cpu_ptr(vlan->pcpu_stats, i);
 487                         do {
 488                                 start = u64_stats_fetch_begin_bh(&p->syncp);
 489                                 rx_packets      = p->rx_packets;
 490                                 rx_bytes        = p->rx_bytes;
 491                                 rx_multicast    = p->rx_multicast;
 492                                 tx_packets      = p->tx_packets;
 493                                 tx_bytes        = p->tx_bytes;
 494                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
 495
 496                         stats->rx_packets       += rx_packets;
 497                         stats->rx_bytes         += rx_bytes;
 498                         stats->multicast        += rx_multicast;
 499                         stats->tx_packets       += tx_packets;
 500                         stats->tx_bytes         += tx_bytes;
 501                         /* rx_errors & tx_dropped are u32, updated
 502                          * without syncp protection.
 503                          */
 504                         rx_errors       += p->rx_errors;
 505                         tx_dropped      += p->tx_dropped;
 506                 }
 507                 stats->rx_errors        = rx_errors;
 508                 stats->rx_dropped       = rx_errors;
 509                 stats->tx_dropped       = tx_dropped;
 510         }
 511         return stats;
 512 }
 513
 514 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 515                                         struct ethtool_drvinfo *drvinfo)
 516 {
 517         snprintf(drvinfo->driver, 32, "macvlan");
 518         snprintf(drvinfo->version, 32, "0.1");
 519 }
 520
 521 static int macvlan_ethtool_get_settings(struct net_device *dev,
 522                                         struct ethtool_cmd *cmd)
 523 {
 524         const struct macvlan_dev *vlan = netdev_priv(dev);
 525         return dev_ethtool_get_settings(vlan->lowerdev, cmd);
 526 }
 527
 528 static const struct ethtool_ops macvlan_ethtool_ops = {
 529         .get_link               = ethtool_op_get_link,
 530         .get_settings           = macvlan_ethtool_get_settings,
 531         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
 532 };
 533
 534 static const struct net_device_ops macvlan_netdev_ops = {
 535         .ndo_init               = macvlan_init,
 536         .ndo_uninit             = macvlan_uninit,
 537         .ndo_open               = macvlan_open,
 538         .ndo_stop               = macvlan_stop,
 539         .ndo_start_xmit         = macvlan_start_xmit,
 540         .ndo_change_mtu         = macvlan_change_mtu,
 541         .ndo_change_rx_flags    = macvlan_change_rx_flags,
 542         .ndo_set_mac_address    = macvlan_set_mac_address,
 543         .ndo_set_multicast_list = macvlan_set_multicast_list,
 544         .ndo_get_stats64        = macvlan_dev_get_stats64,
 545         .ndo_validate_addr      = eth_validate_addr,
 546 };
 547
 548 void macvlan_common_setup(struct net_device *dev)
 549 {
 550         ether_setup(dev);
 551
 552         dev->priv_flags        &= ~IFF_XMIT_DST_RELEASE;
 553         dev->netdev_ops         = &macvlan_netdev_ops;
 554         dev->destructor         = free_netdev;
 555         dev->header_ops         = &macvlan_hard_header_ops,
 556         dev->ethtool_ops        = &macvlan_ethtool_ops;
 557 }
 558 EXPORT_SYMBOL_GPL(macvlan_common_setup);
 559
 560 static void macvlan_setup(struct net_device *dev)
 561 {
 562         macvlan_common_setup(dev);
 563         dev->tx_queue_len       = 0;
 564 }
 565
 566 static int macvlan_port_create(struct net_device *dev)
 567 {
 568         struct macvlan_port *port;
 569         unsigned int i;
 570         int err;
 571
 572         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 573                 return -EINVAL;
 574
 575         port = kzalloc(sizeof(*port), GFP_KERNEL);
 576         if (port == NULL)
 577                 return -ENOMEM;
 578
 579         port->passthru = false;
 580         port->dev = dev;
 581         INIT_LIST_HEAD(&port->vlans);
 582         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 583                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
 584
 585         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
 586         if (err)
 587                 kfree(port);
 588         else
 589                 dev->priv_flags |= IFF_MACVLAN_PORT;
 590         return err;
 591 }
 592
 593 static void macvlan_port_destroy(struct net_device *dev)
 594 {
 595         struct macvlan_port *port = macvlan_port_get(dev);
 596
 597         dev->priv_flags &= ~IFF_MACVLAN_PORT;
 598         netdev_rx_handler_unregister(dev);
 599         kfree_rcu(port, rcu);
 600 }
 601
 602 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 603 {
 604         if (tb[IFLA_ADDRESS]) {
 605                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 606                         return -EINVAL;
 607                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 608                         return -EADDRNOTAVAIL;
 609         }
 610
 611         if (data && data[IFLA_MACVLAN_MODE]) {
 612                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
 613                 case MACVLAN_MODE_PRIVATE:
 614                 case MACVLAN_MODE_VEPA:
 615                 case MACVLAN_MODE_BRIDGE:
 616                 case MACVLAN_MODE_PASSTHRU:
 617                         break;
 618                 default:
 619                         return -EINVAL;
 620                 }
 621         }
 622         return 0;
 623 }
 624
 625 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 626                            struct nlattr *tb[], struct nlattr *data[],
 627                            int (*receive)(struct sk_buff *skb),
 628                            int (*forward)(struct net_device *dev,
 629                                           struct sk_buff *skb))
 630 {
 631         struct macvlan_dev *vlan = netdev_priv(dev);
 632         struct macvlan_port *port;
 633         struct net_device *lowerdev;
 634         int err;
 635
 636         if (!tb[IFLA_LINK])
 637                 return -EINVAL;
 638
 639         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 640         if (lowerdev == NULL)
 641                 return -ENODEV;
 642
 643         /* When creating macvlans on top of other macvlans - use
 644          * the real device as the lowerdev.
 645          */
 646         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
 647                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
 648                 lowerdev = lowervlan->lowerdev;
 649         }
 650
 651         if (!tb[IFLA_MTU])
 652                 dev->mtu = lowerdev->mtu;
 653         else if (dev->mtu > lowerdev->mtu)
 654                 return -EINVAL;
 655
 656         if (!tb[IFLA_ADDRESS])
 657                 random_ether_addr(dev->dev_addr);
 658
 659         if (!macvlan_port_exists(lowerdev)) {
 660                 err = macvlan_port_create(lowerdev);
 661                 if (err < 0)
 662                         return err;
 663         }
 664         port = macvlan_port_get(lowerdev);
 665
 666         /* Only 1 macvlan device can be created in passthru mode */
 667         if (port->passthru)
 668                 return -EINVAL;
 669
 670         vlan->lowerdev = lowerdev;
 671         vlan->dev      = dev;
 672         vlan->port     = port;
 673         vlan->receive  = receive;
 674         vlan->forward  = forward;
 675
 676         vlan->mode     = MACVLAN_MODE_VEPA;
 677         if (data && data[IFLA_MACVLAN_MODE])
 678                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 679
 680         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 681                 if (port->count)
 682                         return -EINVAL;
 683                 port->passthru = true;
 684                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 685         }
 686
 687         port->count += 1;
 688         err = register_netdevice(dev);
 689         if (err < 0)
 690                 goto destroy_port;
 691
 692         list_add_tail(&vlan->list, &port->vlans);
 693         netif_stacked_transfer_operstate(lowerdev, dev);
 694
 695         return 0;
 696
 697 destroy_port:
 698         port->count -= 1;
 699         if (!port->count)
 700                 macvlan_port_destroy(lowerdev);
 701
 702         return err;
 703 }
 704 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
 705
 706 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
 707                            struct nlattr *tb[], struct nlattr *data[])
 708 {
 709         return macvlan_common_newlink(src_net, dev, tb, data,
 710                                       netif_rx,
 711                                       dev_forward_skb);
 712 }
 713
 714 void macvlan_dellink(struct net_device *dev, struct list_head *head)
 715 {
 716         struct macvlan_dev *vlan = netdev_priv(dev);
 717
 718         list_del(&vlan->list);
 719         unregister_netdevice_queue(dev, head);
 720 }
 721 EXPORT_SYMBOL_GPL(macvlan_dellink);
 722
 723 static int macvlan_changelink(struct net_device *dev,
 724                 struct nlattr *tb[], struct nlattr *data[])
 725 {
 726         struct macvlan_dev *vlan = netdev_priv(dev);
 727         if (data && data[IFLA_MACVLAN_MODE])
 728                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 729         return 0;
 730 }
 731
 732 static size_t macvlan_get_size(const struct net_device *dev)
 733 {
 734         return nla_total_size(4);
 735 }
 736
 737 static int macvlan_fill_info(struct sk_buff *skb,
 738                                 const struct net_device *dev)
 739 {
 740         struct macvlan_dev *vlan = netdev_priv(dev);
 741
 742         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
 743         return 0;
 744
 745 nla_put_failure:
 746         return -EMSGSIZE;
 747 }
 748
 749 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
 750         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
 751 };
 752
 753 int macvlan_link_register(struct rtnl_link_ops *ops)
 754 {
 755         /* common fields */
 756         ops->priv_size          = sizeof(struct macvlan_dev);
 757         ops->validate           = macvlan_validate;
 758         ops->maxtype            = IFLA_MACVLAN_MAX;
 759         ops->policy             = macvlan_policy;
 760         ops->changelink         = macvlan_changelink;
 761         ops->get_size           = macvlan_get_size;
 762         ops->fill_info          = macvlan_fill_info;
 763
 764         return rtnl_link_register(ops);
 765 };
 766 EXPORT_SYMBOL_GPL(macvlan_link_register);
 767
 768 static struct rtnl_link_ops macvlan_link_ops = {
 769         .kind           = "macvlan",
 770         .setup          = macvlan_setup,
 771         .newlink        = macvlan_newlink,
 772         .dellink        = macvlan_dellink,
 773 };
 774
 775 static int macvlan_device_event(struct notifier_block *unused,
 776                                 unsigned long event, void *ptr)
 777 {
 778         struct net_device *dev = ptr;
 779         struct macvlan_dev *vlan, *next;
 780         struct macvlan_port *port;
 781         LIST_HEAD(list_kill);
 782
 783         if (!macvlan_port_exists(dev))
 784                 return NOTIFY_DONE;
 785
 786         port = macvlan_port_get(dev);
 787
 788         switch (event) {
 789         case NETDEV_CHANGE:
 790                 list_for_each_entry(vlan, &port->vlans, list)
 791                         netif_stacked_transfer_operstate(vlan->lowerdev,
 792                                                          vlan->dev);
 793                 break;
 794         case NETDEV_FEAT_CHANGE:
 795                 list_for_each_entry(vlan, &port->vlans, list) {
 796                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
 797                         vlan->dev->gso_max_size = dev->gso_max_size;
 798                         netdev_features_change(vlan->dev);
 799                 }
 800                 break;
 801         case NETDEV_UNREGISTER:
 802                 /* twiddle thumbs on netns device moves */
 803                 if (dev->reg_state != NETREG_UNREGISTERING)
 804                         break;
 805
 806                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
 807                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
 808                 unregister_netdevice_many(&list_kill);
 809                 list_del(&list_kill);
 810                 break;
 811         case NETDEV_PRE_TYPE_CHANGE:
 812                 /* Forbid underlaying device to change its type. */
 813                 return NOTIFY_BAD;
 814         }
 815         return NOTIFY_DONE;
 816 }
 817
 818 static struct notifier_block macvlan_notifier_block __read_mostly = {
 819         .notifier_call  = macvlan_device_event,
 820 };
 821
 822 static int __init macvlan_init_module(void)
 823 {
 824         int err;
 825
 826         register_netdevice_notifier(&macvlan_notifier_block);
 827
 828         err = macvlan_link_register(&macvlan_link_ops);
 829         if (err < 0)
 830                 goto err1;
 831         return 0;
 832 err1:
 833         unregister_netdevice_notifier(&macvlan_notifier_block);
 834         return err;
 835 }
 836
 837 static void __exit macvlan_cleanup_module(void)
 838 {
 839         rtnl_link_unregister(&macvlan_link_ops);
 840         unregister_netdevice_notifier(&macvlan_notifier_block);
 841 }
 842
 843 module_init(macvlan_init_module);
 844 module_exit(macvlan_cleanup_module);
 845
 846 MODULE_LICENSE("GPL");
 847 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 848 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 849 MODULE_ALIAS_RTNL_LINK("macvlan");