net/8021q/vlan_dev.c

   1 /* -*- linux-c -*-
   2  * INET         802.1Q VLAN
   3  *              Ethernet-type device handling.
   4  *
   5  * Authors:     Ben Greear <greearb@candelatech.com>
   6  *              Please send support related email to: netdev@vger.kernel.org
   7  *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
   8  *
   9  * Fixes:       Mar 22 2001: Martin Bokaemper <mbokaemper@unispherenetworks.com>
  10  *                - reset skb->pkt_type on incoming packets when MAC was changed
  11  *                - see that changed MAC is saddr for outgoing packets
  12  *              Oct 20, 2001:  Ard van Breeman:
  13  *                - Fix MC-list, finally.
  14  *                - Flush MC-list on VLAN destroy.
  15  *
  16  *
  17  *              This program is free software; you can redistribute it and/or
  18  *              modify it under the terms of the GNU General Public License
  19  *              as published by the Free Software Foundation; either version
  20  *              2 of the License, or (at your option) any later version.
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/mm.h>
  25 #include <linux/in.h>
  26 #include <linux/init.h>
  27 #include <asm/uaccess.h> /* for copy_from_user */
  28 #include <linux/skbuff.h>
  29 #include <linux/netdevice.h>
  30 #include <linux/etherdevice.h>
  31 #include <net/datalink.h>
  32 #include <net/p8022.h>
  33 #include <net/arp.h>
  34
  35 #include "vlan.h"
  36 #include "vlanproc.h"
  37 #include <linux/if_vlan.h>
  38 #include <net/ip.h>
  39
  40 /*
  41  *      Rebuild the Ethernet MAC header. This is called after an ARP
  42  *      (or in future other address resolution) has completed on this
  43  *      sk_buff. We now let ARP fill in the other fields.
  44  *
  45  *      This routine CANNOT use cached dst->neigh!
  46  *      Really, it is used only when dst->neigh is wrong.
  47  *
  48  * TODO:  This needs a checkup, I'm ignorant here. --BLG
  49  */
  50 static int vlan_dev_rebuild_header(struct sk_buff *skb)
  51 {
  52         struct net_device *dev = skb->dev;
  53         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
  54
  55         switch (veth->h_vlan_encapsulated_proto) {
  56 #ifdef CONFIG_INET
  57         case __constant_htons(ETH_P_IP):
  58
  59                 /* TODO:  Confirm this will work with VLAN headers... */
  60                 return arp_find(veth->h_dest, skb);
  61 #endif
  62         default:
  63                 pr_debug("%s: unable to resolve type %X addresses.\n",
  64                          dev->name, ntohs(veth->h_vlan_encapsulated_proto));
  65
  66                 memcpy(veth->h_source, dev->dev_addr, ETH_ALEN);
  67                 break;
  68         }
  69
  70         return 0;
  71 }
  72
  73 static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
  74 {
  75         if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
  76                 if (skb_shared(skb) || skb_cloned(skb)) {
  77                         struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
  78                         kfree_skb(skb);
  79                         skb = nskb;
  80                 }
  81                 if (skb) {
  82                         /* Lifted from Gleb's VLAN code... */
  83                         memmove(skb->data - ETH_HLEN,
  84                                 skb->data - VLAN_ETH_HLEN, 12);
  85                         skb->mac_header += VLAN_HLEN;
  86                 }
  87         }
  88
  89         return skb;
  90 }
  91
  92 static inline void vlan_set_encap_proto(struct sk_buff *skb,
  93                 struct vlan_hdr *vhdr)
  94 {
  95         __be16 proto;
  96         unsigned char *rawp;
  97
  98         /*
  99          * Was a VLAN packet, grab the encapsulated protocol, which the layer
 100          * three protocols care about.
 101          */
 102
 103         proto = vhdr->h_vlan_encapsulated_proto;
 104         if (ntohs(proto) >= 1536) {
 105                 skb->protocol = proto;
 106                 return;
 107         }
 108
 109         rawp = skb->data;
 110         if (*(unsigned short *)rawp == 0xFFFF)
 111                 /*
 112                  * This is a magic hack to spot IPX packets. Older Novell
 113                  * breaks the protocol design and runs IPX over 802.3 without
 114                  * an 802.2 LLC layer. We look for FFFF which isn't a used
 115                  * 802.2 SSAP/DSAP. This won't work for fault tolerant netware
 116                  * but does for the rest.
 117                  */
 118                 skb->protocol = htons(ETH_P_802_3);
 119         else
 120                 /*
 121                  * Real 802.2 LLC
 122                  */
 123                 skb->protocol = htons(ETH_P_802_2);
 124 }
 125
 126 /*
 127  *      Determine the packet's protocol ID. The rule here is that we
 128  *      assume 802.3 if the type field is short enough to be a length.
 129  *      This is normal practice and works for any 'now in use' protocol.
 130  *
 131  *  Also, at this point we assume that we ARE dealing exclusively with
 132  *  VLAN packets, or packets that should be made into VLAN packets based
 133  *  on a default VLAN ID.
 134  *
 135  *  NOTE:  Should be similar to ethernet/eth.c.
 136  *
 137  *  SANITY NOTE:  This method is called when a packet is moving up the stack
 138  *                towards userland.  To get here, it would have already passed
 139  *                through the ethernet/eth.c eth_type_trans() method.
 140  *  SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
 141  *                 stored UNALIGNED in the memory.  RISC systems don't like
 142  *                 such cases very much...
 143  *  SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be
 144  *                  aligned, so there doesn't need to be any of the unaligned
 145  *                  stuff.  It has been commented out now...  --Ben
 146  *
 147  */
 148 int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
 149                   struct packet_type *ptype, struct net_device *orig_dev)
 150 {
 151         struct vlan_hdr *vhdr;
 152         unsigned short vid;
 153         struct net_device_stats *stats;
 154         unsigned short vlan_TCI;
 155
 156         if (dev->nd_net != &init_net)
 157                 goto err_free;
 158
 159         skb = skb_share_check(skb, GFP_ATOMIC);
 160         if (skb == NULL)
 161                 goto err_free;
 162
 163         if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
 164                 goto err_free;
 165
 166         vhdr = (struct vlan_hdr *)skb->data;
 167         vlan_TCI = ntohs(vhdr->h_vlan_TCI);
 168         vid = (vlan_TCI & VLAN_VID_MASK);
 169
 170         rcu_read_lock();
 171         skb->dev = __find_vlan_dev(dev, vid);
 172         if (!skb->dev) {
 173                 pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
 174                          __FUNCTION__, (unsigned int)vid, dev->name);
 175                 goto err_unlock;
 176         }
 177
 178         skb->dev->last_rx = jiffies;
 179
 180         stats = &skb->dev->stats;
 181         stats->rx_packets++;
 182         stats->rx_bytes += skb->len;
 183
 184         skb_pull_rcsum(skb, VLAN_HLEN);
 185
 186         skb->priority = vlan_get_ingress_priority(skb->dev,
 187                                                   ntohs(vhdr->h_vlan_TCI));
 188
 189         pr_debug("%s: priority: %u for TCI: %hu\n",
 190                  __FUNCTION__, skb->priority, ntohs(vhdr->h_vlan_TCI));
 191
 192         switch (skb->pkt_type) {
 193         case PACKET_BROADCAST: /* Yeah, stats collect these together.. */
 194                 /* stats->broadcast ++; // no such counter :-( */
 195                 break;
 196
 197         case PACKET_MULTICAST:
 198                 stats->multicast++;
 199                 break;
 200
 201         case PACKET_OTHERHOST:
 202                 /* Our lower layer thinks this is not local, let's make sure.
 203                  * This allows the VLAN to have a different MAC than the
 204                  * underlying device, and still route correctly.
 205                  */
 206                 if (!compare_ether_addr(eth_hdr(skb)->h_dest,
 207                                         skb->dev->dev_addr))
 208                         skb->pkt_type = PACKET_HOST;
 209                 break;
 210         default:
 211                 break;
 212         }
 213
 214         vlan_set_encap_proto(skb, vhdr);
 215
 216         skb = vlan_check_reorder_header(skb);
 217         if (!skb) {
 218                 stats->rx_errors++;
 219                 goto err_unlock;
 220         }
 221
 222         netif_rx(skb);
 223         rcu_read_unlock();
 224         return NET_RX_SUCCESS;
 225
 226 err_unlock:
 227         rcu_read_unlock();
 228 err_free:
 229         kfree_skb(skb);
 230         return NET_RX_DROP;
 231 }
 232
 233 static inline unsigned short
 234 vlan_dev_get_egress_qos_mask(struct net_device *dev, struct sk_buff *skb)
 235 {
 236         struct vlan_priority_tci_mapping *mp;
 237
 238         mp = vlan_dev_info(dev)->egress_priority_map[(skb->priority & 0xF)];
 239         while (mp) {
 240                 if (mp->priority == skb->priority) {
 241                         return mp->vlan_qos; /* This should already be shifted
 242                                               * to mask correctly with the
 243                                               * VLAN's TCI */
 244                 }
 245                 mp = mp->next;
 246         }
 247         return 0;
 248 }
 249
 250 /*
 251  *      Create the VLAN header for an arbitrary protocol layer
 252  *
 253  *      saddr=NULL      means use device source address
 254  *      daddr=NULL      means leave destination address (eg unresolved arp)
 255  *
 256  *  This is called when the SKB is moving down the stack towards the
 257  *  physical devices.
 258  */
 259 static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev,
 260                                 unsigned short type,
 261                                 const void *daddr, const void *saddr,
 262                                 unsigned int len)
 263 {
 264         struct vlan_hdr *vhdr;
 265         unsigned short veth_TCI = 0;
 266         int rc = 0;
 267         int build_vlan_header = 0;
 268         struct net_device *vdev = dev;
 269
 270         pr_debug("%s: skb: %p type: %hx len: %u vlan_id: %hx, daddr: %p\n",
 271                  __FUNCTION__, skb, type, len, vlan_dev_info(dev)->vlan_id,
 272                  daddr);
 273
 274         /* build vlan header only if re_order_header flag is NOT set.  This
 275          * fixes some programs that get confused when they see a VLAN device
 276          * sending a frame that is VLAN encoded (the consensus is that the VLAN
 277          * device should look completely like an Ethernet device when the
 278          * REORDER_HEADER flag is set)  The drawback to this is some extra
 279          * header shuffling in the hard_start_xmit.  Users can turn off this
 280          * REORDER behaviour with the vconfig tool.
 281          */
 282         if (!(vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR))
 283                 build_vlan_header = 1;
 284
 285         if (build_vlan_header) {
 286                 vhdr = (struct vlan_hdr *) skb_push(skb, VLAN_HLEN);
 287
 288                 /* build the four bytes that make this a VLAN header. */
 289
 290                 /* Now, construct the second two bytes. This field looks
 291                  * something like:
 292                  * usr_priority: 3 bits  (high bits)
 293                  * CFI           1 bit
 294                  * VLAN ID       12 bits (low bits)
 295                  *
 296                  */
 297                 veth_TCI = vlan_dev_info(dev)->vlan_id;
 298                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 299
 300                 vhdr->h_vlan_TCI = htons(veth_TCI);
 301
 302                 /*
 303                  *  Set the protocol type. For a packet of type ETH_P_802_3 we
 304                  *  put the length in here instead. It is up to the 802.2
 305                  *  layer to carry protocol information.
 306                  */
 307
 308                 if (type != ETH_P_802_3)
 309                         vhdr->h_vlan_encapsulated_proto = htons(type);
 310                 else
 311                         vhdr->h_vlan_encapsulated_proto = htons(len);
 312
 313                 skb->protocol = htons(ETH_P_8021Q);
 314                 skb_reset_network_header(skb);
 315         }
 316
 317         /* Before delegating work to the lower layer, enter our MAC-address */
 318         if (saddr == NULL)
 319                 saddr = dev->dev_addr;
 320
 321         dev = vlan_dev_info(dev)->real_dev;
 322
 323         /* MPLS can send us skbuffs w/out enough space. This check will grow
 324          * the skb if it doesn't have enough headroom. Not a beautiful solution,
 325          * so I'll tick a counter so that users can know it's happening...
 326          * If they care...
 327          */
 328
 329         /* NOTE: This may still break if the underlying device is not the final
 330          * device (and thus there are more headers to add...) It should work for
 331          * good-ole-ethernet though.
 332          */
 333         if (skb_headroom(skb) < dev->hard_header_len) {
 334                 struct sk_buff *sk_tmp = skb;
 335                 skb = skb_realloc_headroom(sk_tmp, dev->hard_header_len);
 336                 kfree_skb(sk_tmp);
 337                 if (skb == NULL) {
 338                         struct net_device_stats *stats = &vdev->stats;
 339                         stats->tx_dropped++;
 340                         return -ENOMEM;
 341                 }
 342                 vlan_dev_info(vdev)->cnt_inc_headroom_on_tx++;
 343                 pr_debug("%s: %s: had to grow skb\n", __FUNCTION__, vdev->name);
 344         }
 345
 346         if (build_vlan_header) {
 347                 /* Now make the underlying real hard header */
 348                 rc = dev_hard_header(skb, dev, ETH_P_8021Q, daddr, saddr,
 349                                      len + VLAN_HLEN);
 350                 if (rc > 0)
 351                         rc += VLAN_HLEN;
 352                 else if (rc < 0)
 353                         rc -= VLAN_HLEN;
 354         } else
 355                 /* If here, then we'll just make a normal looking ethernet
 356                  * frame, but, the hard_start_xmit method will insert the tag
 357                  * (it has to be able to do this for bridged and other skbs
 358                  * that don't come down the protocol stack in an orderly manner.
 359                  */
 360                 rc = dev_hard_header(skb, dev, type, daddr, saddr, len);
 361
 362         return rc;
 363 }
 364
 365 static int vlan_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
 366 {
 367         struct net_device_stats *stats = &dev->stats;
 368         struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
 369
 370         /* Handle non-VLAN frames if they are sent to us, for example by DHCP.
 371          *
 372          * NOTE: THIS ASSUMES DIX ETHERNET, SPECIFICALLY NOT SUPPORTING
 373          * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
 374          */
 375
 376         if (veth->h_vlan_proto != htons(ETH_P_8021Q) ||
 377                 vlan_dev_info(dev)->flags & VLAN_FLAG_REORDER_HDR) {
 378                 int orig_headroom = skb_headroom(skb);
 379                 unsigned short veth_TCI;
 380
 381                 /* This is not a VLAN frame...but we can fix that! */
 382                 vlan_dev_info(dev)->cnt_encap_on_xmit++;
 383
 384                 pr_debug("%s: proto to encap: 0x%hx\n",
 385                          __FUNCTION__, htons(veth->h_vlan_proto));
 386                 /* Construct the second two bytes. This field looks something
 387                  * like:
 388                  * usr_priority: 3 bits  (high bits)
 389                  * CFI           1 bit
 390                  * VLAN ID       12 bits (low bits)
 391                  */
 392                 veth_TCI = vlan_dev_info(dev)->vlan_id;
 393                 veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 394
 395                 skb = __vlan_put_tag(skb, veth_TCI);
 396                 if (!skb) {
 397                         stats->tx_dropped++;
 398                         return 0;
 399                 }
 400
 401                 if (orig_headroom < VLAN_HLEN)
 402                         vlan_dev_info(dev)->cnt_inc_headroom_on_tx++;
 403         }
 404
 405         pr_debug("%s: about to send skb: %p to dev: %s\n",
 406                 __FUNCTION__, skb, skb->dev->name);
 407         pr_debug("  " MAC_FMT " " MAC_FMT " %4hx %4hx %4hx\n",
 408                  veth->h_dest[0], veth->h_dest[1], veth->h_dest[2],
 409                  veth->h_dest[3], veth->h_dest[4], veth->h_dest[5],
 410                  veth->h_source[0], veth->h_source[1], veth->h_source[2],
 411                  veth->h_source[3], veth->h_source[4], veth->h_source[5],
 412                  veth->h_vlan_proto, veth->h_vlan_TCI,
 413                  veth->h_vlan_encapsulated_proto);
 414
 415         stats->tx_packets++; /* for statics only */
 416         stats->tx_bytes += skb->len;
 417
 418         skb->dev = vlan_dev_info(dev)->real_dev;
 419         dev_queue_xmit(skb);
 420
 421         return 0;
 422 }
 423
 424 static int vlan_dev_hwaccel_hard_start_xmit(struct sk_buff *skb,
 425                                             struct net_device *dev)
 426 {
 427         struct net_device_stats *stats = &dev->stats;
 428         unsigned short veth_TCI;
 429
 430         /* Construct the second two bytes. This field looks something
 431          * like:
 432          * usr_priority: 3 bits  (high bits)
 433          * CFI           1 bit
 434          * VLAN ID       12 bits (low bits)
 435          */
 436         veth_TCI = vlan_dev_info(dev)->vlan_id;
 437         veth_TCI |= vlan_dev_get_egress_qos_mask(dev, skb);
 438         skb = __vlan_hwaccel_put_tag(skb, veth_TCI);
 439
 440         stats->tx_packets++;
 441         stats->tx_bytes += skb->len;
 442
 443         skb->dev = vlan_dev_info(dev)->real_dev;
 444         dev_queue_xmit(skb);
 445
 446         return 0;
 447 }
 448
 449 static int vlan_dev_change_mtu(struct net_device *dev, int new_mtu)
 450 {
 451         /* TODO: gotta make sure the underlying layer can handle it,
 452          * maybe an IFF_VLAN_CAPABLE flag for devices?
 453          */
 454         if (vlan_dev_info(dev)->real_dev->mtu < new_mtu)
 455                 return -ERANGE;
 456
 457         dev->mtu = new_mtu;
 458
 459         return 0;
 460 }
 461
 462 void vlan_dev_set_ingress_priority(const struct net_device *dev,
 463                                    u32 skb_prio, short vlan_prio)
 464 {
 465         struct vlan_dev_info *vlan = vlan_dev_info(dev);
 466
 467         if (vlan->ingress_priority_map[vlan_prio & 0x7] && !skb_prio)
 468                 vlan->nr_ingress_mappings--;
 469         else if (!vlan->ingress_priority_map[vlan_prio & 0x7] && skb_prio)
 470                 vlan->nr_ingress_mappings++;
 471
 472         vlan->ingress_priority_map[vlan_prio & 0x7] = skb_prio;
 473 }
 474
 475 int vlan_dev_set_egress_priority(const struct net_device *dev,
 476                                  u32 skb_prio, short vlan_prio)
 477 {
 478         struct vlan_dev_info *vlan = vlan_dev_info(dev);
 479         struct vlan_priority_tci_mapping *mp = NULL;
 480         struct vlan_priority_tci_mapping *np;
 481         u32 vlan_qos = (vlan_prio << 13) & 0xE000;
 482
 483         /* See if a priority mapping exists.. */
 484         mp = vlan->egress_priority_map[skb_prio & 0xF];
 485         while (mp) {
 486                 if (mp->priority == skb_prio) {
 487                         if (mp->vlan_qos && !vlan_qos)
 488                                 vlan->nr_egress_mappings--;
 489                         else if (!mp->vlan_qos && vlan_qos)
 490                                 vlan->nr_egress_mappings++;
 491                         mp->vlan_qos = vlan_qos;
 492                         return 0;
 493                 }
 494                 mp = mp->next;
 495         }
 496
 497         /* Create a new mapping then. */
 498         mp = vlan->egress_priority_map[skb_prio & 0xF];
 499         np = kmalloc(sizeof(struct vlan_priority_tci_mapping), GFP_KERNEL);
 500         if (!np)
 501                 return -ENOBUFS;
 502
 503         np->next = mp;
 504         np->priority = skb_prio;
 505         np->vlan_qos = vlan_qos;
 506         vlan->egress_priority_map[skb_prio & 0xF] = np;
 507         if (vlan_qos)
 508                 vlan->nr_egress_mappings++;
 509         return 0;
 510 }
 511
 512 /* Flags are defined in the vlan_flags enum in include/linux/if_vlan.h file. */
 513 int vlan_dev_set_vlan_flag(const struct net_device *dev,
 514                            u32 flag, short flag_val)
 515 {
 516         /* verify flag is supported */
 517         if (flag == VLAN_FLAG_REORDER_HDR) {
 518                 if (flag_val)
 519                         vlan_dev_info(dev)->flags |= VLAN_FLAG_REORDER_HDR;
 520                 else
 521                         vlan_dev_info(dev)->flags &= ~VLAN_FLAG_REORDER_HDR;
 522                 return 0;
 523         }
 524         return -EINVAL;
 525 }
 526
 527 void vlan_dev_get_realdev_name(const struct net_device *dev, char *result)
 528 {
 529         strncpy(result, vlan_dev_info(dev)->real_dev->name, 23);
 530 }
 531
 532 void vlan_dev_get_vid(const struct net_device *dev, unsigned short *result)
 533 {
 534         *result = vlan_dev_info(dev)->vlan_id;
 535 }
 536
 537 static int vlan_dev_open(struct net_device *dev)
 538 {
 539         struct vlan_dev_info *vlan = vlan_dev_info(dev);
 540         struct net_device *real_dev = vlan->real_dev;
 541         int err;
 542
 543         if (!(real_dev->flags & IFF_UP))
 544                 return -ENETDOWN;
 545
 546         if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) {
 547                 err = dev_unicast_add(real_dev, dev->dev_addr, ETH_ALEN);
 548                 if (err < 0)
 549                         return err;
 550         }
 551         memcpy(vlan->real_dev_addr, real_dev->dev_addr, ETH_ALEN);
 552
 553         if (dev->flags & IFF_ALLMULTI)
 554                 dev_set_allmulti(real_dev, 1);
 555         if (dev->flags & IFF_PROMISC)
 556                 dev_set_promiscuity(real_dev, 1);
 557
 558         return 0;
 559 }
 560
 561 static int vlan_dev_stop(struct net_device *dev)
 562 {
 563         struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
 564
 565         dev_mc_unsync(real_dev, dev);
 566         if (dev->flags & IFF_ALLMULTI)
 567                 dev_set_allmulti(real_dev, -1);
 568         if (dev->flags & IFF_PROMISC)
 569                 dev_set_promiscuity(real_dev, -1);
 570
 571         if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
 572                 dev_unicast_delete(real_dev, dev->dev_addr, dev->addr_len);
 573
 574         return 0;
 575 }
 576
 577 static int vlan_dev_set_mac_address(struct net_device *dev, void *p)
 578 {
 579         struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
 580         struct sockaddr *addr = p;
 581         int err;
 582
 583         if (!is_valid_ether_addr(addr->sa_data))
 584                 return -EADDRNOTAVAIL;
 585
 586         if (!(dev->flags & IFF_UP))
 587                 goto out;
 588
 589         if (compare_ether_addr(addr->sa_data, real_dev->dev_addr)) {
 590                 err = dev_unicast_add(real_dev, addr->sa_data, ETH_ALEN);
 591                 if (err < 0)
 592                         return err;
 593         }
 594
 595         if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr))
 596                 dev_unicast_delete(real_dev, dev->dev_addr, ETH_ALEN);
 597
 598 out:
 599         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 600         return 0;
 601 }
 602
 603 static int vlan_dev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 604 {
 605         struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
 606         struct ifreq ifrr;
 607         int err = -EOPNOTSUPP;
 608
 609         strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
 610         ifrr.ifr_ifru = ifr->ifr_ifru;
 611
 612         switch (cmd) {
 613         case SIOCGMIIPHY:
 614         case SIOCGMIIREG:
 615         case SIOCSMIIREG:
 616                 if (real_dev->do_ioctl && netif_device_present(real_dev))
 617                         err = real_dev->do_ioctl(real_dev, &ifrr, cmd);
 618                 break;
 619         }
 620
 621         if (!err)
 622                 ifr->ifr_ifru = ifrr.ifr_ifru;
 623
 624         return err;
 625 }
 626
 627 static void vlan_dev_change_rx_flags(struct net_device *dev, int change)
 628 {
 629         struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
 630
 631         if (change & IFF_ALLMULTI)
 632                 dev_set_allmulti(real_dev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 633         if (change & IFF_PROMISC)
 634                 dev_set_promiscuity(real_dev, dev->flags & IFF_PROMISC ? 1 : -1);
 635 }
 636
 637 static void vlan_dev_set_multicast_list(struct net_device *vlan_dev)
 638 {
 639         dev_mc_sync(vlan_dev_info(vlan_dev)->real_dev, vlan_dev);
 640 }
 641
 642 /*
 643  * vlan network devices have devices nesting below it, and are a special
 644  * "super class" of normal network devices; split their locks off into a
 645  * separate class since they always nest.
 646  */
 647 static struct lock_class_key vlan_netdev_xmit_lock_key;
 648
 649 static const struct header_ops vlan_header_ops = {
 650         .create  = vlan_dev_hard_header,
 651         .rebuild = vlan_dev_rebuild_header,
 652         .parse   = eth_header_parse,
 653 };
 654
 655 static int vlan_dev_init(struct net_device *dev)
 656 {
 657         struct net_device *real_dev = vlan_dev_info(dev)->real_dev;
 658         int subclass = 0;
 659
 660         /* IFF_BROADCAST|IFF_MULTICAST; ??? */
 661         dev->flags  = real_dev->flags & ~IFF_UP;
 662         dev->iflink = real_dev->ifindex;
 663         dev->state  = (real_dev->state & ((1<<__LINK_STATE_NOCARRIER) |
 664                                           (1<<__LINK_STATE_DORMANT))) |
 665                       (1<<__LINK_STATE_PRESENT);
 666
 667         /* ipv6 shared card related stuff */
 668         dev->dev_id = real_dev->dev_id;
 669
 670         if (is_zero_ether_addr(dev->dev_addr))
 671                 memcpy(dev->dev_addr, real_dev->dev_addr, dev->addr_len);
 672         if (is_zero_ether_addr(dev->broadcast))
 673                 memcpy(dev->broadcast, real_dev->broadcast, dev->addr_len);
 674
 675         if (real_dev->features & NETIF_F_HW_VLAN_TX) {
 676                 dev->header_ops      = real_dev->header_ops;
 677                 dev->hard_header_len = real_dev->hard_header_len;
 678                 dev->hard_start_xmit = vlan_dev_hwaccel_hard_start_xmit;
 679         } else {
 680                 dev->header_ops      = &vlan_header_ops;
 681                 dev->hard_header_len = real_dev->hard_header_len + VLAN_HLEN;
 682                 dev->hard_start_xmit = vlan_dev_hard_start_xmit;
 683         }
 684
 685         if (real_dev->priv_flags & IFF_802_1Q_VLAN)
 686                 subclass = 1;
 687
 688         lockdep_set_class_and_subclass(&dev->_xmit_lock,
 689                                 &vlan_netdev_xmit_lock_key, subclass);
 690         return 0;
 691 }
 692
 693 void vlan_setup(struct net_device *dev)
 694 {
 695         ether_setup(dev);
 696
 697         dev->priv_flags         |= IFF_802_1Q_VLAN;
 698         dev->tx_queue_len       = 0;
 699
 700         dev->change_mtu         = vlan_dev_change_mtu;
 701         dev->init               = vlan_dev_init;
 702         dev->open               = vlan_dev_open;
 703         dev->stop               = vlan_dev_stop;
 704         dev->set_mac_address    = vlan_dev_set_mac_address;
 705         dev->set_multicast_list = vlan_dev_set_multicast_list;
 706         dev->change_rx_flags    = vlan_dev_change_rx_flags;
 707         dev->do_ioctl           = vlan_dev_ioctl;
 708         dev->destructor         = free_netdev;
 709
 710         memset(dev->broadcast, 0, ETH_ALEN);
 711 }