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 #include <net/l3mdev.h>
  39
  40 #define DRV_NAME        "vrf"
  41 #define DRV_VERSION     "1.0"
  42
  43 #define vrf_is_slave(dev)   ((dev)->flags & IFF_SLAVE)
  44
  45 #define vrf_master_get_rcu(dev) \
  46         ((struct net_device *)rcu_dereference(dev->rx_handler_data))
  47
  48 struct pcpu_dstats {
  49         u64                     tx_pkts;
  50         u64                     tx_bytes;
  51         u64                     tx_drps;
  52         u64                     rx_pkts;
  53         u64                     rx_bytes;
  54         struct u64_stats_sync   syncp;
  55 };
  56
  57 static struct dst_entry *vrf_ip_check(struct dst_entry *dst, u32 cookie)
  58 {
  59         return dst;
  60 }
  61
  62 static int vrf_ip_local_out(struct sk_buff *skb)
  63 {
  64         return ip_local_out(skb);
  65 }
  66
  67 static unsigned int vrf_v4_mtu(const struct dst_entry *dst)
  68 {
  69         /* TO-DO: return max ethernet size? */
  70         return dst->dev->mtu;
  71 }
  72
  73 static void vrf_dst_destroy(struct dst_entry *dst)
  74 {
  75         /* our dst lives forever - or until the device is closed */
  76 }
  77
  78 static unsigned int vrf_default_advmss(const struct dst_entry *dst)
  79 {
  80         return 65535 - 40;
  81 }
  82
  83 static struct dst_ops vrf_dst_ops = {
  84         .family         = AF_INET,
  85         .local_out      = vrf_ip_local_out,
  86         .check          = vrf_ip_check,
  87         .mtu            = vrf_v4_mtu,
  88         .destroy        = vrf_dst_destroy,
  89         .default_advmss = vrf_default_advmss,
  90 };
  91
  92 static bool is_ip_rx_frame(struct sk_buff *skb)
  93 {
  94         switch (skb->protocol) {
  95         case htons(ETH_P_IP):
  96         case htons(ETH_P_IPV6):
  97                 return true;
  98         }
  99         return false;
 100 }
 101
 102 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
 103 {
 104         vrf_dev->stats.tx_errors++;
 105         kfree_skb(skb);
 106 }
 107
 108 /* note: already called with rcu_read_lock */
 109 static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
 110 {
 111         struct sk_buff *skb = *pskb;
 112
 113         if (is_ip_rx_frame(skb)) {
 114                 struct net_device *dev = vrf_master_get_rcu(skb->dev);
 115                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 116
 117                 u64_stats_update_begin(&dstats->syncp);
 118                 dstats->rx_pkts++;
 119                 dstats->rx_bytes += skb->len;
 120                 u64_stats_update_end(&dstats->syncp);
 121
 122                 skb->dev = dev;
 123
 124                 return RX_HANDLER_ANOTHER;
 125         }
 126         return RX_HANDLER_PASS;
 127 }
 128
 129 static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
 130                                                  struct rtnl_link_stats64 *stats)
 131 {
 132         int i;
 133
 134         for_each_possible_cpu(i) {
 135                 const struct pcpu_dstats *dstats;
 136                 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
 137                 unsigned int start;
 138
 139                 dstats = per_cpu_ptr(dev->dstats, i);
 140                 do {
 141                         start = u64_stats_fetch_begin_irq(&dstats->syncp);
 142                         tbytes = dstats->tx_bytes;
 143                         tpkts = dstats->tx_pkts;
 144                         tdrops = dstats->tx_drps;
 145                         rbytes = dstats->rx_bytes;
 146                         rpkts = dstats->rx_pkts;
 147                 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
 148                 stats->tx_bytes += tbytes;
 149                 stats->tx_packets += tpkts;
 150                 stats->tx_dropped += tdrops;
 151                 stats->rx_bytes += rbytes;
 152                 stats->rx_packets += rpkts;
 153         }
 154         return stats;
 155 }
 156
 157 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 158                                            struct net_device *dev)
 159 {
 160         vrf_tx_error(dev, skb);
 161         return NET_XMIT_DROP;
 162 }
 163
 164 static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
 165                             struct net_device *vrf_dev)
 166 {
 167         struct rtable *rt;
 168         int err = 1;
 169
 170         rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
 171         if (IS_ERR(rt))
 172                 goto out;
 173
 174         /* TO-DO: what about broadcast ? */
 175         if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
 176                 ip_rt_put(rt);
 177                 goto out;
 178         }
 179
 180         skb_dst_drop(skb);
 181         skb_dst_set(skb, &rt->dst);
 182         err = 0;
 183 out:
 184         return err;
 185 }
 186
 187 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
 188                                            struct net_device *vrf_dev)
 189 {
 190         struct iphdr *ip4h = ip_hdr(skb);
 191         int ret = NET_XMIT_DROP;
 192         struct flowi4 fl4 = {
 193                 /* needed to match OIF rule */
 194                 .flowi4_oif = vrf_dev->ifindex,
 195                 .flowi4_iif = LOOPBACK_IFINDEX,
 196                 .flowi4_tos = RT_TOS(ip4h->tos),
 197                 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_VRFSRC |
 198                                 FLOWI_FLAG_SKIP_NH_OIF,
 199                 .daddr = ip4h->daddr,
 200         };
 201
 202         if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
 203                 goto err;
 204
 205         if (!ip4h->saddr) {
 206                 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
 207                                                RT_SCOPE_LINK);
 208         }
 209
 210         ret = ip_local_out(skb);
 211         if (unlikely(net_xmit_eval(ret)))
 212                 vrf_dev->stats.tx_errors++;
 213         else
 214                 ret = NET_XMIT_SUCCESS;
 215
 216 out:
 217         return ret;
 218 err:
 219         vrf_tx_error(vrf_dev, skb);
 220         goto out;
 221 }
 222
 223 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
 224 {
 225         /* strip the ethernet header added for pass through VRF device */
 226         __skb_pull(skb, skb_network_offset(skb));
 227
 228         switch (skb->protocol) {
 229         case htons(ETH_P_IP):
 230                 return vrf_process_v4_outbound(skb, dev);
 231         case htons(ETH_P_IPV6):
 232                 return vrf_process_v6_outbound(skb, dev);
 233         default:
 234                 vrf_tx_error(dev, skb);
 235                 return NET_XMIT_DROP;
 236         }
 237 }
 238
 239 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
 240 {
 241         netdev_tx_t ret = is_ip_tx_frame(skb, dev);
 242
 243         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 244                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 245
 246                 u64_stats_update_begin(&dstats->syncp);
 247                 dstats->tx_pkts++;
 248                 dstats->tx_bytes += skb->len;
 249                 u64_stats_update_end(&dstats->syncp);
 250         } else {
 251                 this_cpu_inc(dev->dstats->tx_drps);
 252         }
 253
 254         return ret;
 255 }
 256
 257 /* modelled after ip_finish_output2 */
 258 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 259 {
 260         struct dst_entry *dst = skb_dst(skb);
 261         struct rtable *rt = (struct rtable *)dst;
 262         struct net_device *dev = dst->dev;
 263         unsigned int hh_len = LL_RESERVED_SPACE(dev);
 264         struct neighbour *neigh;
 265         u32 nexthop;
 266         int ret = -EINVAL;
 267
 268         /* Be paranoid, rather than too clever. */
 269         if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
 270                 struct sk_buff *skb2;
 271
 272                 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
 273                 if (!skb2) {
 274                         ret = -ENOMEM;
 275                         goto err;
 276                 }
 277                 if (skb->sk)
 278                         skb_set_owner_w(skb2, skb->sk);
 279
 280                 consume_skb(skb);
 281                 skb = skb2;
 282         }
 283
 284         rcu_read_lock_bh();
 285
 286         nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
 287         neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
 288         if (unlikely(!neigh))
 289                 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
 290         if (!IS_ERR(neigh))
 291                 ret = dst_neigh_output(dst, neigh, skb);
 292
 293         rcu_read_unlock_bh();
 294 err:
 295         if (unlikely(ret < 0))
 296                 vrf_tx_error(skb->dev, skb);
 297         return ret;
 298 }
 299
 300 static int vrf_output(struct sock *sk, struct sk_buff *skb)
 301 {
 302         struct net_device *dev = skb_dst(skb)->dev;
 303         struct net *net = dev_net(dev);
 304
 305         IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
 306
 307         skb->dev = dev;
 308         skb->protocol = htons(ETH_P_IP);
 309
 310         return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
 311                             net, sk, skb, NULL, dev,
 312                             vrf_finish_output,
 313                             !(IPCB(skb)->flags & IPSKB_REROUTED));
 314 }
 315
 316 static void vrf_rtable_destroy(struct net_vrf *vrf)
 317 {
 318         struct dst_entry *dst = (struct dst_entry *)vrf->rth;
 319
 320         dst_destroy(dst);
 321         vrf->rth = NULL;
 322 }
 323
 324 static struct rtable *vrf_rtable_create(struct net_device *dev)
 325 {
 326         struct net_vrf *vrf = netdev_priv(dev);
 327         struct rtable *rth;
 328
 329         rth = dst_alloc(&vrf_dst_ops, dev, 2,
 330                         DST_OBSOLETE_NONE,
 331                         (DST_HOST | DST_NOPOLICY | DST_NOXFRM));
 332         if (rth) {
 333                 rth->dst.output = vrf_output;
 334                 rth->rt_genid   = rt_genid_ipv4(dev_net(dev));
 335                 rth->rt_flags   = 0;
 336                 rth->rt_type    = RTN_UNICAST;
 337                 rth->rt_is_input = 0;
 338                 rth->rt_iif     = 0;
 339                 rth->rt_pmtu    = 0;
 340                 rth->rt_gateway = 0;
 341                 rth->rt_uses_gateway = 0;
 342                 rth->rt_table_id = vrf->tb_id;
 343                 INIT_LIST_HEAD(&rth->rt_uncached);
 344                 rth->rt_uncached_list = NULL;
 345         }
 346
 347         return rth;
 348 }
 349
 350 /**************************** device handling ********************/
 351
 352 /* cycle interface to flush neighbor cache and move routes across tables */
 353 static void cycle_netdev(struct net_device *dev)
 354 {
 355         unsigned int flags = dev->flags;
 356         int ret;
 357
 358         if (!netif_running(dev))
 359                 return;
 360
 361         ret = dev_change_flags(dev, flags & ~IFF_UP);
 362         if (ret >= 0)
 363                 ret = dev_change_flags(dev, flags);
 364
 365         if (ret < 0) {
 366                 netdev_err(dev,
 367                            "Failed to cycle device %s; route tables might be wrong!\n",
 368                            dev->name);
 369         }
 370 }
 371
 372 static struct slave *__vrf_find_slave_dev(struct slave_queue *queue,
 373                                           struct net_device *dev)
 374 {
 375         struct list_head *head = &queue->all_slaves;
 376         struct slave *slave;
 377
 378         list_for_each_entry(slave, head, list) {
 379                 if (slave->dev == dev)
 380                         return slave;
 381         }
 382
 383         return NULL;
 384 }
 385
 386 /* inverse of __vrf_insert_slave */
 387 static void __vrf_remove_slave(struct slave_queue *queue, struct slave *slave)
 388 {
 389         list_del(&slave->list);
 390 }
 391
 392 static void __vrf_insert_slave(struct slave_queue *queue, struct slave *slave)
 393 {
 394         list_add(&slave->list, &queue->all_slaves);
 395 }
 396
 397 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 398 {
 399         struct slave *slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 400         struct net_vrf *vrf = netdev_priv(dev);
 401         struct slave_queue *queue = &vrf->queue;
 402         int ret = -ENOMEM;
 403
 404         if (!slave)
 405                 goto out_fail;
 406
 407         slave->dev = port_dev;
 408
 409         /* register the packet handler for slave ports */
 410         ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
 411         if (ret) {
 412                 netdev_err(port_dev,
 413                            "Device %s failed to register rx_handler\n",
 414                            port_dev->name);
 415                 goto out_fail;
 416         }
 417
 418         ret = netdev_master_upper_dev_link(port_dev, dev);
 419         if (ret < 0)
 420                 goto out_unregister;
 421
 422         port_dev->flags |= IFF_SLAVE;
 423         __vrf_insert_slave(queue, slave);
 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(slave);
 432         return ret;
 433 }
 434
 435 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 436 {
 437         if (netif_is_l3_master(port_dev) || vrf_is_slave(port_dev))
 438                 return -EINVAL;
 439
 440         return do_vrf_add_slave(dev, port_dev);
 441 }
 442
 443 /* inverse of do_vrf_add_slave */
 444 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 445 {
 446         struct net_vrf *vrf = netdev_priv(dev);
 447         struct slave_queue *queue = &vrf->queue;
 448         struct slave *slave;
 449
 450         netdev_upper_dev_unlink(port_dev, dev);
 451         port_dev->flags &= ~IFF_SLAVE;
 452
 453         netdev_rx_handler_unregister(port_dev);
 454
 455         cycle_netdev(port_dev);
 456
 457         slave = __vrf_find_slave_dev(queue, port_dev);
 458         if (slave)
 459                 __vrf_remove_slave(queue, slave);
 460
 461         kfree(slave);
 462
 463         return 0;
 464 }
 465
 466 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 467 {
 468         return do_vrf_del_slave(dev, port_dev);
 469 }
 470
 471 static void vrf_dev_uninit(struct net_device *dev)
 472 {
 473         struct net_vrf *vrf = netdev_priv(dev);
 474         struct slave_queue *queue = &vrf->queue;
 475         struct list_head *head = &queue->all_slaves;
 476         struct slave *slave, *next;
 477
 478         vrf_rtable_destroy(vrf);
 479
 480         list_for_each_entry_safe(slave, next, head, list)
 481                 vrf_del_slave(dev, slave->dev);
 482
 483         free_percpu(dev->dstats);
 484         dev->dstats = NULL;
 485 }
 486
 487 static int vrf_dev_init(struct net_device *dev)
 488 {
 489         struct net_vrf *vrf = netdev_priv(dev);
 490
 491         INIT_LIST_HEAD(&vrf->queue.all_slaves);
 492
 493         dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
 494         if (!dev->dstats)
 495                 goto out_nomem;
 496
 497         /* create the default dst which points back to us */
 498         vrf->rth = vrf_rtable_create(dev);
 499         if (!vrf->rth)
 500                 goto out_stats;
 501
 502         dev->flags = IFF_MASTER | IFF_NOARP;
 503
 504         return 0;
 505
 506 out_stats:
 507         free_percpu(dev->dstats);
 508         dev->dstats = NULL;
 509 out_nomem:
 510         return -ENOMEM;
 511 }
 512
 513 static const struct net_device_ops vrf_netdev_ops = {
 514         .ndo_init               = vrf_dev_init,
 515         .ndo_uninit             = vrf_dev_uninit,
 516         .ndo_start_xmit         = vrf_xmit,
 517         .ndo_get_stats64        = vrf_get_stats64,
 518         .ndo_add_slave          = vrf_add_slave,
 519         .ndo_del_slave          = vrf_del_slave,
 520 };
 521
 522 static u32 vrf_fib_table(const struct net_device *dev)
 523 {
 524         struct net_vrf *vrf = netdev_priv(dev);
 525
 526         return vrf->tb_id;
 527 }
 528
 529 static struct rtable *vrf_get_rtable(const struct net_device *dev,
 530                                      const struct flowi4 *fl4)
 531 {
 532         struct rtable *rth = NULL;
 533
 534         if (!(fl4->flowi4_flags & FLOWI_FLAG_VRFSRC)) {
 535                 struct net_vrf *vrf = netdev_priv(dev);
 536
 537                 rth = vrf->rth;
 538                 atomic_inc(&rth->dst.__refcnt);
 539         }
 540
 541         return rth;
 542 }
 543
 544 static const struct l3mdev_ops vrf_l3mdev_ops = {
 545         .l3mdev_fib_table       = vrf_fib_table,
 546         .l3mdev_get_rtable      = vrf_get_rtable,
 547 };
 548
 549 static void vrf_get_drvinfo(struct net_device *dev,
 550                             struct ethtool_drvinfo *info)
 551 {
 552         strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
 553         strlcpy(info->version, DRV_VERSION, sizeof(info->version));
 554 }
 555
 556 static const struct ethtool_ops vrf_ethtool_ops = {
 557         .get_drvinfo    = vrf_get_drvinfo,
 558 };
 559
 560 static void vrf_setup(struct net_device *dev)
 561 {
 562         ether_setup(dev);
 563
 564         /* Initialize the device structure. */
 565         dev->netdev_ops = &vrf_netdev_ops;
 566         dev->l3mdev_ops = &vrf_l3mdev_ops;
 567         dev->ethtool_ops = &vrf_ethtool_ops;
 568         dev->destructor = free_netdev;
 569
 570         /* Fill in device structure with ethernet-generic values. */
 571         eth_hw_addr_random(dev);
 572
 573         /* don't acquire vrf device's netif_tx_lock when transmitting */
 574         dev->features |= NETIF_F_LLTX;
 575
 576         /* don't allow vrf devices to change network namespaces. */
 577         dev->features |= NETIF_F_NETNS_LOCAL;
 578 }
 579
 580 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
 581 {
 582         if (tb[IFLA_ADDRESS]) {
 583                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 584                         return -EINVAL;
 585                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 586                         return -EADDRNOTAVAIL;
 587         }
 588         return 0;
 589 }
 590
 591 static void vrf_dellink(struct net_device *dev, struct list_head *head)
 592 {
 593         unregister_netdevice_queue(dev, head);
 594 }
 595
 596 static int vrf_newlink(struct net *src_net, struct net_device *dev,
 597                        struct nlattr *tb[], struct nlattr *data[])
 598 {
 599         struct net_vrf *vrf = netdev_priv(dev);
 600         int err;
 601
 602         if (!data || !data[IFLA_VRF_TABLE])
 603                 return -EINVAL;
 604
 605         vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
 606
 607         dev->priv_flags |= IFF_L3MDEV_MASTER;
 608
 609         err = register_netdevice(dev);
 610         if (err < 0)
 611                 goto out_fail;
 612
 613         return 0;
 614
 615 out_fail:
 616         free_netdev(dev);
 617         return err;
 618 }
 619
 620 static size_t vrf_nl_getsize(const struct net_device *dev)
 621 {
 622         return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
 623 }
 624
 625 static int vrf_fillinfo(struct sk_buff *skb,
 626                         const struct net_device *dev)
 627 {
 628         struct net_vrf *vrf = netdev_priv(dev);
 629
 630         return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
 631 }
 632
 633 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
 634         [IFLA_VRF_TABLE] = { .type = NLA_U32 },
 635 };
 636
 637 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
 638         .kind           = DRV_NAME,
 639         .priv_size      = sizeof(struct net_vrf),
 640
 641         .get_size       = vrf_nl_getsize,
 642         .policy         = vrf_nl_policy,
 643         .validate       = vrf_validate,
 644         .fill_info      = vrf_fillinfo,
 645
 646         .newlink        = vrf_newlink,
 647         .dellink        = vrf_dellink,
 648         .setup          = vrf_setup,
 649         .maxtype        = IFLA_VRF_MAX,
 650 };
 651
 652 static int vrf_device_event(struct notifier_block *unused,
 653                             unsigned long event, void *ptr)
 654 {
 655         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 656
 657         /* only care about unregister events to drop slave references */
 658         if (event == NETDEV_UNREGISTER) {
 659                 struct net_device *vrf_dev;
 660
 661                 if (netif_is_l3_master(dev))
 662                         goto out;
 663
 664                 vrf_dev = netdev_master_upper_dev_get(dev);
 665                 vrf_del_slave(vrf_dev, dev);
 666         }
 667 out:
 668         return NOTIFY_DONE;
 669 }
 670
 671 static struct notifier_block vrf_notifier_block __read_mostly = {
 672         .notifier_call = vrf_device_event,
 673 };
 674
 675 static int __init vrf_init_module(void)
 676 {
 677         int rc;
 678
 679         vrf_dst_ops.kmem_cachep =
 680                 kmem_cache_create("vrf_ip_dst_cache",
 681                                   sizeof(struct rtable), 0,
 682                                   SLAB_HWCACHE_ALIGN,
 683                                   NULL);
 684
 685         if (!vrf_dst_ops.kmem_cachep)
 686                 return -ENOMEM;
 687
 688         register_netdevice_notifier(&vrf_notifier_block);
 689
 690         rc = rtnl_link_register(&vrf_link_ops);
 691         if (rc < 0)
 692                 goto error;
 693
 694         return 0;
 695
 696 error:
 697         unregister_netdevice_notifier(&vrf_notifier_block);
 698         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 699         return rc;
 700 }
 701
 702 static void __exit vrf_cleanup_module(void)
 703 {
 704         rtnl_link_unregister(&vrf_link_ops);
 705         unregister_netdevice_notifier(&vrf_notifier_block);
 706         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 707 }
 708
 709 module_init(vrf_init_module);
 710 module_exit(vrf_cleanup_module);
 711 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
 712 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
 713 MODULE_LICENSE("GPL");
 714 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
 715 MODULE_VERSION(DRV_VERSION);