drivers/net/vrf.c

   1 /*
   2  * vrf.c: device driver to encapsulate a VRF space
   3  *
   4  * Copyright (c) 2015 Cumulus Networks. All rights reserved.
   5  * Copyright (c) 2015 Shrijeet Mukherjee <shm@cumulusnetworks.com>
   6  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
   7  *
   8  * Based on dummy, team and ipvlan drivers
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/etherdevice.h>
  20 #include <linux/ip.h>
  21 #include <linux/init.h>
  22 #include <linux/moduleparam.h>
  23 #include <linux/netfilter.h>
  24 #include <linux/rtnetlink.h>
  25 #include <net/rtnetlink.h>
  26 #include <linux/u64_stats_sync.h>
  27 #include <linux/hashtable.h>
  28
  29 #include <linux/inetdevice.h>
  30 #include <net/arp.h>
  31 #include <net/ip.h>
  32 #include <net/ip_fib.h>
  33 #include <net/ip6_route.h>
  34 #include <net/rtnetlink.h>
  35 #include <net/route.h>
  36 #include <net/addrconf.h>
  37 #include <net/vrf.h>
  38
  39 #define DRV_NAME        "vrf"
  40 #define DRV_VERSION     "1.0"
  41
  42 #define vrf_is_slave(dev)   ((dev)->flags & IFF_SLAVE)
  43
  44 #define vrf_master_get_rcu(dev) \
  45         ((struct net_device *)rcu_dereference(dev->rx_handler_data))
  46
  47 struct pcpu_dstats {
  48         u64                     tx_pkts;
  49         u64                     tx_bytes;
  50         u64                     tx_drps;
  51         u64                     rx_pkts;
  52         u64                     rx_bytes;
  53         struct u64_stats_sync   syncp;
  54 };
  55
  56 static struct dst_entry *vrf_ip_check(struct dst_entry *dst, u32 cookie)
  57 {
  58         return dst;
  59 }
  60
  61 static int vrf_ip_local_out(struct sk_buff *skb)
  62 {
  63         return ip_local_out(skb);
  64 }
  65
  66 static unsigned int vrf_v4_mtu(const struct dst_entry *dst)
  67 {
  68         /* TO-DO: return max ethernet size? */
  69         return dst->dev->mtu;
  70 }
  71
  72 static void vrf_dst_destroy(struct dst_entry *dst)
  73 {
  74         /* our dst lives forever - or until the device is closed */
  75 }
  76
  77 static unsigned int vrf_default_advmss(const struct dst_entry *dst)
  78 {
  79         return 65535 - 40;
  80 }
  81
  82 static struct dst_ops vrf_dst_ops = {
  83         .family         = AF_INET,
  84         .local_out      = vrf_ip_local_out,
  85         .check          = vrf_ip_check,
  86         .mtu            = vrf_v4_mtu,
  87         .destroy        = vrf_dst_destroy,
  88         .default_advmss = vrf_default_advmss,
  89 };
  90
  91 static bool is_ip_rx_frame(struct sk_buff *skb)
  92 {
  93         switch (skb->protocol) {
  94         case htons(ETH_P_IP):
  95         case htons(ETH_P_IPV6):
  96                 return true;
  97         }
  98         return false;
  99 }
 100
 101 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
 102 {
 103         vrf_dev->stats.tx_errors++;
 104         kfree_skb(skb);
 105 }
 106
 107 /* note: already called with rcu_read_lock */
 108 static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
 109 {
 110         struct sk_buff *skb = *pskb;
 111
 112         if (is_ip_rx_frame(skb)) {
 113                 struct net_device *dev = vrf_master_get_rcu(skb->dev);
 114                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 115
 116                 u64_stats_update_begin(&dstats->syncp);
 117                 dstats->rx_pkts++;
 118                 dstats->rx_bytes += skb->len;
 119                 u64_stats_update_end(&dstats->syncp);
 120
 121                 skb->dev = dev;
 122
 123                 return RX_HANDLER_ANOTHER;
 124         }
 125         return RX_HANDLER_PASS;
 126 }
 127
 128 static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
 129                                                  struct rtnl_link_stats64 *stats)
 130 {
 131         int i;
 132
 133         for_each_possible_cpu(i) {
 134                 const struct pcpu_dstats *dstats;
 135                 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
 136                 unsigned int start;
 137
 138                 dstats = per_cpu_ptr(dev->dstats, i);
 139                 do {
 140                         start = u64_stats_fetch_begin_irq(&dstats->syncp);
 141                         tbytes = dstats->tx_bytes;
 142                         tpkts = dstats->tx_pkts;
 143                         tdrops = dstats->tx_drps;
 144                         rbytes = dstats->rx_bytes;
 145                         rpkts = dstats->rx_pkts;
 146                 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
 147                 stats->tx_bytes += tbytes;
 148                 stats->tx_packets += tpkts;
 149                 stats->tx_dropped += tdrops;
 150                 stats->rx_bytes += rbytes;
 151                 stats->rx_packets += rpkts;
 152         }
 153         return stats;
 154 }
 155
 156 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 157                                            struct net_device *dev)
 158 {
 159         vrf_tx_error(dev, skb);
 160         return NET_XMIT_DROP;
 161 }
 162
 163 static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
 164                             struct net_device *vrf_dev)
 165 {
 166         struct rtable *rt;
 167         int err = 1;
 168
 169         rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
 170         if (IS_ERR(rt))
 171                 goto out;
 172
 173         /* TO-DO: what about broadcast ? */
 174         if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
 175                 ip_rt_put(rt);
 176                 goto out;
 177         }
 178
 179         skb_dst_drop(skb);
 180         skb_dst_set(skb, &rt->dst);
 181         err = 0;
 182 out:
 183         return err;
 184 }
 185
 186 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
 187                                            struct net_device *vrf_dev)
 188 {
 189         struct iphdr *ip4h = ip_hdr(skb);
 190         int ret = NET_XMIT_DROP;
 191         struct flowi4 fl4 = {
 192                 /* needed to match OIF rule */
 193                 .flowi4_oif = vrf_dev->ifindex,
 194                 .flowi4_iif = LOOPBACK_IFINDEX,
 195                 .flowi4_tos = RT_TOS(ip4h->tos),
 196                 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_VRFSRC |
 197                                 FLOWI_FLAG_SKIP_NH_OIF,
 198                 .daddr = ip4h->daddr,
 199         };
 200
 201         if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
 202                 goto err;
 203
 204         if (!ip4h->saddr) {
 205                 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
 206                                                RT_SCOPE_LINK);
 207         }
 208
 209         ret = ip_local_out(skb);
 210         if (unlikely(net_xmit_eval(ret)))
 211                 vrf_dev->stats.tx_errors++;
 212         else
 213                 ret = NET_XMIT_SUCCESS;
 214
 215 out:
 216         return ret;
 217 err:
 218         vrf_tx_error(vrf_dev, skb);
 219         goto out;
 220 }
 221
 222 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
 223 {
 224         /* strip the ethernet header added for pass through VRF device */
 225         __skb_pull(skb, skb_network_offset(skb));
 226
 227         switch (skb->protocol) {
 228         case htons(ETH_P_IP):
 229                 return vrf_process_v4_outbound(skb, dev);
 230         case htons(ETH_P_IPV6):
 231                 return vrf_process_v6_outbound(skb, dev);
 232         default:
 233                 vrf_tx_error(dev, skb);
 234                 return NET_XMIT_DROP;
 235         }
 236 }
 237
 238 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
 239 {
 240         netdev_tx_t ret = is_ip_tx_frame(skb, dev);
 241
 242         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 243                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 244
 245                 u64_stats_update_begin(&dstats->syncp);
 246                 dstats->tx_pkts++;
 247                 dstats->tx_bytes += skb->len;
 248                 u64_stats_update_end(&dstats->syncp);
 249         } else {
 250                 this_cpu_inc(dev->dstats->tx_drps);
 251         }
 252
 253         return ret;
 254 }
 255
 256 /* modelled after ip_finish_output2 */
 257 static int vrf_finish_output(struct sock *sk, struct sk_buff *skb)
 258 {
 259         struct dst_entry *dst = skb_dst(skb);
 260         struct rtable *rt = (struct rtable *)dst;
 261         struct net_device *dev = dst->dev;
 262         unsigned int hh_len = LL_RESERVED_SPACE(dev);
 263         struct neighbour *neigh;
 264         u32 nexthop;
 265         int ret = -EINVAL;
 266
 267         /* Be paranoid, rather than too clever. */
 268         if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
 269                 struct sk_buff *skb2;
 270
 271                 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
 272                 if (!skb2) {
 273                         ret = -ENOMEM;
 274                         goto err;
 275                 }
 276                 if (skb->sk)
 277                         skb_set_owner_w(skb2, skb->sk);
 278
 279                 consume_skb(skb);
 280                 skb = skb2;
 281         }
 282
 283         rcu_read_lock_bh();
 284
 285         nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
 286         neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
 287         if (unlikely(!neigh))
 288                 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
 289         if (!IS_ERR(neigh))
 290                 ret = dst_neigh_output(dst, neigh, skb);
 291
 292         rcu_read_unlock_bh();
 293 err:
 294         if (unlikely(ret < 0))
 295                 vrf_tx_error(skb->dev, skb);
 296         return ret;
 297 }
 298
 299 static int vrf_output(struct sock *sk, struct sk_buff *skb)
 300 {
 301         struct net_device *dev = skb_dst(skb)->dev;
 302
 303         IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
 304
 305         skb->dev = dev;
 306         skb->protocol = htons(ETH_P_IP);
 307
 308         return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING, sk, skb,
 309                             NULL, dev,
 310                             vrf_finish_output,
 311                             !(IPCB(skb)->flags & IPSKB_REROUTED));
 312 }
 313
 314 static void vrf_rtable_destroy(struct net_vrf *vrf)
 315 {
 316         struct dst_entry *dst = (struct dst_entry *)vrf->rth;
 317
 318         dst_destroy(dst);
 319         vrf->rth = NULL;
 320 }
 321
 322 static struct rtable *vrf_rtable_create(struct net_device *dev)
 323 {
 324         struct rtable *rth;
 325
 326         rth = dst_alloc(&vrf_dst_ops, dev, 2,
 327                         DST_OBSOLETE_NONE,
 328                         (DST_HOST | DST_NOPOLICY | DST_NOXFRM));
 329         if (rth) {
 330                 rth->dst.output = vrf_output;
 331                 rth->rt_genid   = rt_genid_ipv4(dev_net(dev));
 332                 rth->rt_flags   = 0;
 333                 rth->rt_type    = RTN_UNICAST;
 334                 rth->rt_is_input = 0;
 335                 rth->rt_iif     = 0;
 336                 rth->rt_pmtu    = 0;
 337                 rth->rt_gateway = 0;
 338                 rth->rt_uses_gateway = 0;
 339                 INIT_LIST_HEAD(&rth->rt_uncached);
 340                 rth->rt_uncached_list = NULL;
 341         }
 342
 343         return rth;
 344 }
 345
 346 /**************************** device handling ********************/
 347
 348 /* cycle interface to flush neighbor cache and move routes across tables */
 349 static void cycle_netdev(struct net_device *dev)
 350 {
 351         unsigned int flags = dev->flags;
 352         int ret;
 353
 354         if (!netif_running(dev))
 355                 return;
 356
 357         ret = dev_change_flags(dev, flags & ~IFF_UP);
 358         if (ret >= 0)
 359                 ret = dev_change_flags(dev, flags);
 360
 361         if (ret < 0) {
 362                 netdev_err(dev,
 363                            "Failed to cycle device %s; route tables might be wrong!\n",
 364                            dev->name);
 365         }
 366 }
 367
 368 static struct slave *__vrf_find_slave_dev(struct slave_queue *queue,
 369                                           struct net_device *dev)
 370 {
 371         struct list_head *head = &queue->all_slaves;
 372         struct slave *slave;
 373
 374         list_for_each_entry(slave, head, list) {
 375                 if (slave->dev == dev)
 376                         return slave;
 377         }
 378
 379         return NULL;
 380 }
 381
 382 /* inverse of __vrf_insert_slave */
 383 static void __vrf_remove_slave(struct slave_queue *queue, struct slave *slave)
 384 {
 385         list_del(&slave->list);
 386 }
 387
 388 static void __vrf_insert_slave(struct slave_queue *queue, struct slave *slave)
 389 {
 390         list_add(&slave->list, &queue->all_slaves);
 391 }
 392
 393 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 394 {
 395         struct net_vrf_dev *vrf_ptr = kmalloc(sizeof(*vrf_ptr), GFP_KERNEL);
 396         struct slave *slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 397         struct net_vrf *vrf = netdev_priv(dev);
 398         struct slave_queue *queue = &vrf->queue;
 399         int ret = -ENOMEM;
 400
 401         if (!slave || !vrf_ptr)
 402                 goto out_fail;
 403
 404         slave->dev = port_dev;
 405         vrf_ptr->ifindex = dev->ifindex;
 406         vrf_ptr->tb_id = vrf->tb_id;
 407
 408         /* register the packet handler for slave ports */
 409         ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
 410         if (ret) {
 411                 netdev_err(port_dev,
 412                            "Device %s failed to register rx_handler\n",
 413                            port_dev->name);
 414                 goto out_fail;
 415         }
 416
 417         ret = netdev_master_upper_dev_link(port_dev, dev);
 418         if (ret < 0)
 419                 goto out_unregister;
 420
 421         port_dev->flags |= IFF_SLAVE;
 422         __vrf_insert_slave(queue, slave);
 423         rcu_assign_pointer(port_dev->vrf_ptr, vrf_ptr);
 424         cycle_netdev(port_dev);
 425
 426         return 0;
 427
 428 out_unregister:
 429         netdev_rx_handler_unregister(port_dev);
 430 out_fail:
 431         kfree(vrf_ptr);
 432         kfree(slave);
 433         return ret;
 434 }
 435
 436 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 437 {
 438         if (netif_is_vrf(port_dev) || vrf_is_slave(port_dev))
 439                 return -EINVAL;
 440
 441         return do_vrf_add_slave(dev, port_dev);
 442 }
 443
 444 /* inverse of do_vrf_add_slave */
 445 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 446 {
 447         struct net_vrf_dev *vrf_ptr = rtnl_dereference(port_dev->vrf_ptr);
 448         struct net_vrf *vrf = netdev_priv(dev);
 449         struct slave_queue *queue = &vrf->queue;
 450         struct slave *slave;
 451
 452         RCU_INIT_POINTER(port_dev->vrf_ptr, NULL);
 453
 454         netdev_upper_dev_unlink(port_dev, dev);
 455         port_dev->flags &= ~IFF_SLAVE;
 456
 457         netdev_rx_handler_unregister(port_dev);
 458
 459         /* after netdev_rx_handler_unregister for synchronize_rcu */
 460         kfree(vrf_ptr);
 461
 462         cycle_netdev(port_dev);
 463
 464         slave = __vrf_find_slave_dev(queue, port_dev);
 465         if (slave)
 466                 __vrf_remove_slave(queue, slave);
 467
 468         kfree(slave);
 469
 470         return 0;
 471 }
 472
 473 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 474 {
 475         return do_vrf_del_slave(dev, port_dev);
 476 }
 477
 478 static void vrf_dev_uninit(struct net_device *dev)
 479 {
 480         struct net_vrf *vrf = netdev_priv(dev);
 481         struct slave_queue *queue = &vrf->queue;
 482         struct list_head *head = &queue->all_slaves;
 483         struct slave *slave, *next;
 484
 485         vrf_rtable_destroy(vrf);
 486
 487         list_for_each_entry_safe(slave, next, head, list)
 488                 vrf_del_slave(dev, slave->dev);
 489
 490         free_percpu(dev->dstats);
 491         dev->dstats = NULL;
 492 }
 493
 494 static int vrf_dev_init(struct net_device *dev)
 495 {
 496         struct net_vrf *vrf = netdev_priv(dev);
 497
 498         INIT_LIST_HEAD(&vrf->queue.all_slaves);
 499
 500         dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
 501         if (!dev->dstats)
 502                 goto out_nomem;
 503
 504         /* create the default dst which points back to us */
 505         vrf->rth = vrf_rtable_create(dev);
 506         if (!vrf->rth)
 507                 goto out_stats;
 508
 509         dev->flags = IFF_MASTER | IFF_NOARP;
 510
 511         return 0;
 512
 513 out_stats:
 514         free_percpu(dev->dstats);
 515         dev->dstats = NULL;
 516 out_nomem:
 517         return -ENOMEM;
 518 }
 519
 520 static const struct net_device_ops vrf_netdev_ops = {
 521         .ndo_init               = vrf_dev_init,
 522         .ndo_uninit             = vrf_dev_uninit,
 523         .ndo_start_xmit         = vrf_xmit,
 524         .ndo_get_stats64        = vrf_get_stats64,
 525         .ndo_add_slave          = vrf_add_slave,
 526         .ndo_del_slave          = vrf_del_slave,
 527 };
 528
 529 static void vrf_get_drvinfo(struct net_device *dev,
 530                             struct ethtool_drvinfo *info)
 531 {
 532         strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
 533         strlcpy(info->version, DRV_VERSION, sizeof(info->version));
 534 }
 535
 536 static const struct ethtool_ops vrf_ethtool_ops = {
 537         .get_drvinfo    = vrf_get_drvinfo,
 538 };
 539
 540 static void vrf_setup(struct net_device *dev)
 541 {
 542         ether_setup(dev);
 543
 544         /* Initialize the device structure. */
 545         dev->netdev_ops = &vrf_netdev_ops;
 546         dev->ethtool_ops = &vrf_ethtool_ops;
 547         dev->destructor = free_netdev;
 548
 549         /* Fill in device structure with ethernet-generic values. */
 550         eth_hw_addr_random(dev);
 551
 552         /* don't acquire vrf device's netif_tx_lock when transmitting */
 553         dev->features |= NETIF_F_LLTX;
 554
 555         /* don't allow vrf devices to change network namespaces. */
 556         dev->features |= NETIF_F_NETNS_LOCAL;
 557 }
 558
 559 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
 560 {
 561         if (tb[IFLA_ADDRESS]) {
 562                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 563                         return -EINVAL;
 564                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 565                         return -EADDRNOTAVAIL;
 566         }
 567         return 0;
 568 }
 569
 570 static void vrf_dellink(struct net_device *dev, struct list_head *head)
 571 {
 572         struct net_vrf_dev *vrf_ptr = rtnl_dereference(dev->vrf_ptr);
 573
 574         RCU_INIT_POINTER(dev->vrf_ptr, NULL);
 575         kfree_rcu(vrf_ptr, rcu);
 576         unregister_netdevice_queue(dev, head);
 577 }
 578
 579 static int vrf_newlink(struct net *src_net, struct net_device *dev,
 580                        struct nlattr *tb[], struct nlattr *data[])
 581 {
 582         struct net_vrf *vrf = netdev_priv(dev);
 583         struct net_vrf_dev *vrf_ptr;
 584         int err;
 585
 586         if (!data || !data[IFLA_VRF_TABLE])
 587                 return -EINVAL;
 588
 589         vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
 590
 591         dev->priv_flags |= IFF_VRF_MASTER;
 592
 593         err = -ENOMEM;
 594         vrf_ptr = kmalloc(sizeof(*dev->vrf_ptr), GFP_KERNEL);
 595         if (!vrf_ptr)
 596                 goto out_fail;
 597
 598         vrf_ptr->ifindex = dev->ifindex;
 599         vrf_ptr->tb_id = vrf->tb_id;
 600
 601         err = register_netdevice(dev);
 602         if (err < 0)
 603                 goto out_fail;
 604
 605         rcu_assign_pointer(dev->vrf_ptr, vrf_ptr);
 606
 607         return 0;
 608
 609 out_fail:
 610         kfree(vrf_ptr);
 611         free_netdev(dev);
 612         return err;
 613 }
 614
 615 static size_t vrf_nl_getsize(const struct net_device *dev)
 616 {
 617         return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
 618 }
 619
 620 static int vrf_fillinfo(struct sk_buff *skb,
 621                         const struct net_device *dev)
 622 {
 623         struct net_vrf *vrf = netdev_priv(dev);
 624
 625         return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
 626 }
 627
 628 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
 629         [IFLA_VRF_TABLE] = { .type = NLA_U32 },
 630 };
 631
 632 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
 633         .kind           = DRV_NAME,
 634         .priv_size      = sizeof(struct net_vrf),
 635
 636         .get_size       = vrf_nl_getsize,
 637         .policy         = vrf_nl_policy,
 638         .validate       = vrf_validate,
 639         .fill_info      = vrf_fillinfo,
 640
 641         .newlink        = vrf_newlink,
 642         .dellink        = vrf_dellink,
 643         .setup          = vrf_setup,
 644         .maxtype        = IFLA_VRF_MAX,
 645 };
 646
 647 static int vrf_device_event(struct notifier_block *unused,
 648                             unsigned long event, void *ptr)
 649 {
 650         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 651
 652         /* only care about unregister events to drop slave references */
 653         if (event == NETDEV_UNREGISTER) {
 654                 struct net_vrf_dev *vrf_ptr = rtnl_dereference(dev->vrf_ptr);
 655                 struct net_device *vrf_dev;
 656
 657                 if (!vrf_ptr || netif_is_vrf(dev))
 658                         goto out;
 659
 660                 vrf_dev = netdev_master_upper_dev_get(dev);
 661                 vrf_del_slave(vrf_dev, dev);
 662         }
 663 out:
 664         return NOTIFY_DONE;
 665 }
 666
 667 static struct notifier_block vrf_notifier_block __read_mostly = {
 668         .notifier_call = vrf_device_event,
 669 };
 670
 671 static int __init vrf_init_module(void)
 672 {
 673         int rc;
 674
 675         vrf_dst_ops.kmem_cachep =
 676                 kmem_cache_create("vrf_ip_dst_cache",
 677                                   sizeof(struct rtable), 0,
 678                                   SLAB_HWCACHE_ALIGN,
 679                                   NULL);
 680
 681         if (!vrf_dst_ops.kmem_cachep)
 682                 return -ENOMEM;
 683
 684         register_netdevice_notifier(&vrf_notifier_block);
 685
 686         rc = rtnl_link_register(&vrf_link_ops);
 687         if (rc < 0)
 688                 goto error;
 689
 690         return 0;
 691
 692 error:
 693         unregister_netdevice_notifier(&vrf_notifier_block);
 694         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 695         return rc;
 696 }
 697
 698 static void __exit vrf_cleanup_module(void)
 699 {
 700         rtnl_link_unregister(&vrf_link_ops);
 701         unregister_netdevice_notifier(&vrf_notifier_block);
 702         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 703 }
 704
 705 module_init(vrf_init_module);
 706 module_exit(vrf_cleanup_module);
 707 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
 708 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
 709 MODULE_LICENSE("GPL");
 710 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
 711 MODULE_VERSION(DRV_VERSION);