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/l3mdev.h>
  38
  39 #define RT_FL_TOS(oldflp4) \
  40         ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
  41
  42 #define DRV_NAME        "vrf"
  43 #define DRV_VERSION     "1.0"
  44
  45 #define vrf_master_get_rcu(dev) \
  46         ((struct net_device *)rcu_dereference(dev->rx_handler_data))
  47
  48 struct slave {
  49         struct list_head        list;
  50         struct net_device       *dev;
  51 };
  52
  53 struct slave_queue {
  54         struct list_head        all_slaves;
  55 };
  56
  57 struct net_vrf {
  58         struct slave_queue      queue;
  59         struct rtable           *rth;
  60         u32                     tb_id;
  61 };
  62
  63 struct pcpu_dstats {
  64         u64                     tx_pkts;
  65         u64                     tx_bytes;
  66         u64                     tx_drps;
  67         u64                     rx_pkts;
  68         u64                     rx_bytes;
  69         struct u64_stats_sync   syncp;
  70 };
  71
  72 static struct dst_entry *vrf_ip_check(struct dst_entry *dst, u32 cookie)
  73 {
  74         return dst;
  75 }
  76
  77 static int vrf_ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb)
  78 {
  79         return ip_local_out(sk, skb);
  80 }
  81
  82 static unsigned int vrf_v4_mtu(const struct dst_entry *dst)
  83 {
  84         /* TO-DO: return max ethernet size? */
  85         return dst->dev->mtu;
  86 }
  87
  88 static void vrf_dst_destroy(struct dst_entry *dst)
  89 {
  90         /* our dst lives forever - or until the device is closed */
  91 }
  92
  93 static unsigned int vrf_default_advmss(const struct dst_entry *dst)
  94 {
  95         return 65535 - 40;
  96 }
  97
  98 static struct dst_ops vrf_dst_ops = {
  99         .family         = AF_INET,
 100         .local_out      = vrf_ip_local_out,
 101         .check          = vrf_ip_check,
 102         .mtu            = vrf_v4_mtu,
 103         .destroy        = vrf_dst_destroy,
 104         .default_advmss = vrf_default_advmss,
 105 };
 106
 107 static bool is_ip_rx_frame(struct sk_buff *skb)
 108 {
 109         switch (skb->protocol) {
 110         case htons(ETH_P_IP):
 111         case htons(ETH_P_IPV6):
 112                 return true;
 113         }
 114         return false;
 115 }
 116
 117 static void vrf_tx_error(struct net_device *vrf_dev, struct sk_buff *skb)
 118 {
 119         vrf_dev->stats.tx_errors++;
 120         kfree_skb(skb);
 121 }
 122
 123 /* note: already called with rcu_read_lock */
 124 static rx_handler_result_t vrf_handle_frame(struct sk_buff **pskb)
 125 {
 126         struct sk_buff *skb = *pskb;
 127
 128         if (is_ip_rx_frame(skb)) {
 129                 struct net_device *dev = vrf_master_get_rcu(skb->dev);
 130                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 131
 132                 u64_stats_update_begin(&dstats->syncp);
 133                 dstats->rx_pkts++;
 134                 dstats->rx_bytes += skb->len;
 135                 u64_stats_update_end(&dstats->syncp);
 136
 137                 skb->dev = dev;
 138
 139                 return RX_HANDLER_ANOTHER;
 140         }
 141         return RX_HANDLER_PASS;
 142 }
 143
 144 static struct rtnl_link_stats64 *vrf_get_stats64(struct net_device *dev,
 145                                                  struct rtnl_link_stats64 *stats)
 146 {
 147         int i;
 148
 149         for_each_possible_cpu(i) {
 150                 const struct pcpu_dstats *dstats;
 151                 u64 tbytes, tpkts, tdrops, rbytes, rpkts;
 152                 unsigned int start;
 153
 154                 dstats = per_cpu_ptr(dev->dstats, i);
 155                 do {
 156                         start = u64_stats_fetch_begin_irq(&dstats->syncp);
 157                         tbytes = dstats->tx_bytes;
 158                         tpkts = dstats->tx_pkts;
 159                         tdrops = dstats->tx_drps;
 160                         rbytes = dstats->rx_bytes;
 161                         rpkts = dstats->rx_pkts;
 162                 } while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
 163                 stats->tx_bytes += tbytes;
 164                 stats->tx_packets += tpkts;
 165                 stats->tx_dropped += tdrops;
 166                 stats->rx_bytes += rbytes;
 167                 stats->rx_packets += rpkts;
 168         }
 169         return stats;
 170 }
 171
 172 static netdev_tx_t vrf_process_v6_outbound(struct sk_buff *skb,
 173                                            struct net_device *dev)
 174 {
 175         vrf_tx_error(dev, skb);
 176         return NET_XMIT_DROP;
 177 }
 178
 179 static int vrf_send_v4_prep(struct sk_buff *skb, struct flowi4 *fl4,
 180                             struct net_device *vrf_dev)
 181 {
 182         struct rtable *rt;
 183         int err = 1;
 184
 185         rt = ip_route_output_flow(dev_net(vrf_dev), fl4, NULL);
 186         if (IS_ERR(rt))
 187                 goto out;
 188
 189         /* TO-DO: what about broadcast ? */
 190         if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
 191                 ip_rt_put(rt);
 192                 goto out;
 193         }
 194
 195         skb_dst_drop(skb);
 196         skb_dst_set(skb, &rt->dst);
 197         err = 0;
 198 out:
 199         return err;
 200 }
 201
 202 static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
 203                                            struct net_device *vrf_dev)
 204 {
 205         struct iphdr *ip4h = ip_hdr(skb);
 206         int ret = NET_XMIT_DROP;
 207         struct flowi4 fl4 = {
 208                 /* needed to match OIF rule */
 209                 .flowi4_oif = vrf_dev->ifindex,
 210                 .flowi4_iif = LOOPBACK_IFINDEX,
 211                 .flowi4_tos = RT_TOS(ip4h->tos),
 212                 .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_L3MDEV_SRC |
 213                                 FLOWI_FLAG_SKIP_NH_OIF,
 214                 .daddr = ip4h->daddr,
 215         };
 216
 217         if (vrf_send_v4_prep(skb, &fl4, vrf_dev))
 218                 goto err;
 219
 220         if (!ip4h->saddr) {
 221                 ip4h->saddr = inet_select_addr(skb_dst(skb)->dev, 0,
 222                                                RT_SCOPE_LINK);
 223         }
 224
 225         ret = ip_local_out(skb->sk, skb);
 226         if (unlikely(net_xmit_eval(ret)))
 227                 vrf_dev->stats.tx_errors++;
 228         else
 229                 ret = NET_XMIT_SUCCESS;
 230
 231 out:
 232         return ret;
 233 err:
 234         vrf_tx_error(vrf_dev, skb);
 235         goto out;
 236 }
 237
 238 static netdev_tx_t is_ip_tx_frame(struct sk_buff *skb, struct net_device *dev)
 239 {
 240         /* strip the ethernet header added for pass through VRF device */
 241         __skb_pull(skb, skb_network_offset(skb));
 242
 243         switch (skb->protocol) {
 244         case htons(ETH_P_IP):
 245                 return vrf_process_v4_outbound(skb, dev);
 246         case htons(ETH_P_IPV6):
 247                 return vrf_process_v6_outbound(skb, dev);
 248         default:
 249                 vrf_tx_error(dev, skb);
 250                 return NET_XMIT_DROP;
 251         }
 252 }
 253
 254 static netdev_tx_t vrf_xmit(struct sk_buff *skb, struct net_device *dev)
 255 {
 256         netdev_tx_t ret = is_ip_tx_frame(skb, dev);
 257
 258         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 259                 struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
 260
 261                 u64_stats_update_begin(&dstats->syncp);
 262                 dstats->tx_pkts++;
 263                 dstats->tx_bytes += skb->len;
 264                 u64_stats_update_end(&dstats->syncp);
 265         } else {
 266                 this_cpu_inc(dev->dstats->tx_drps);
 267         }
 268
 269         return ret;
 270 }
 271
 272 /* modelled after ip_finish_output2 */
 273 static int vrf_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 274 {
 275         struct dst_entry *dst = skb_dst(skb);
 276         struct rtable *rt = (struct rtable *)dst;
 277         struct net_device *dev = dst->dev;
 278         unsigned int hh_len = LL_RESERVED_SPACE(dev);
 279         struct neighbour *neigh;
 280         u32 nexthop;
 281         int ret = -EINVAL;
 282
 283         /* Be paranoid, rather than too clever. */
 284         if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
 285                 struct sk_buff *skb2;
 286
 287                 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev));
 288                 if (!skb2) {
 289                         ret = -ENOMEM;
 290                         goto err;
 291                 }
 292                 if (skb->sk)
 293                         skb_set_owner_w(skb2, skb->sk);
 294
 295                 consume_skb(skb);
 296                 skb = skb2;
 297         }
 298
 299         rcu_read_lock_bh();
 300
 301         nexthop = (__force u32)rt_nexthop(rt, ip_hdr(skb)->daddr);
 302         neigh = __ipv4_neigh_lookup_noref(dev, nexthop);
 303         if (unlikely(!neigh))
 304                 neigh = __neigh_create(&arp_tbl, &nexthop, dev, false);
 305         if (!IS_ERR(neigh))
 306                 ret = dst_neigh_output(dst, neigh, skb);
 307
 308         rcu_read_unlock_bh();
 309 err:
 310         if (unlikely(ret < 0))
 311                 vrf_tx_error(skb->dev, skb);
 312         return ret;
 313 }
 314
 315 static int vrf_output(struct sock *sk, struct sk_buff *skb)
 316 {
 317         struct net_device *dev = skb_dst(skb)->dev;
 318         struct net *net = dev_net(dev);
 319
 320         IP_UPD_PO_STATS(net, IPSTATS_MIB_OUT, skb->len);
 321
 322         skb->dev = dev;
 323         skb->protocol = htons(ETH_P_IP);
 324
 325         return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
 326                             net, sk, skb, NULL, dev,
 327                             vrf_finish_output,
 328                             !(IPCB(skb)->flags & IPSKB_REROUTED));
 329 }
 330
 331 static void vrf_rtable_destroy(struct net_vrf *vrf)
 332 {
 333         struct dst_entry *dst = (struct dst_entry *)vrf->rth;
 334
 335         dst_destroy(dst);
 336         vrf->rth = NULL;
 337 }
 338
 339 static struct rtable *vrf_rtable_create(struct net_device *dev)
 340 {
 341         struct net_vrf *vrf = netdev_priv(dev);
 342         struct rtable *rth;
 343
 344         rth = dst_alloc(&vrf_dst_ops, dev, 2,
 345                         DST_OBSOLETE_NONE,
 346                         (DST_HOST | DST_NOPOLICY | DST_NOXFRM));
 347         if (rth) {
 348                 rth->dst.output = vrf_output;
 349                 rth->rt_genid   = rt_genid_ipv4(dev_net(dev));
 350                 rth->rt_flags   = 0;
 351                 rth->rt_type    = RTN_UNICAST;
 352                 rth->rt_is_input = 0;
 353                 rth->rt_iif     = 0;
 354                 rth->rt_pmtu    = 0;
 355                 rth->rt_gateway = 0;
 356                 rth->rt_uses_gateway = 0;
 357                 rth->rt_table_id = vrf->tb_id;
 358                 INIT_LIST_HEAD(&rth->rt_uncached);
 359                 rth->rt_uncached_list = NULL;
 360         }
 361
 362         return rth;
 363 }
 364
 365 /**************************** device handling ********************/
 366
 367 /* cycle interface to flush neighbor cache and move routes across tables */
 368 static void cycle_netdev(struct net_device *dev)
 369 {
 370         unsigned int flags = dev->flags;
 371         int ret;
 372
 373         if (!netif_running(dev))
 374                 return;
 375
 376         ret = dev_change_flags(dev, flags & ~IFF_UP);
 377         if (ret >= 0)
 378                 ret = dev_change_flags(dev, flags);
 379
 380         if (ret < 0) {
 381                 netdev_err(dev,
 382                            "Failed to cycle device %s; route tables might be wrong!\n",
 383                            dev->name);
 384         }
 385 }
 386
 387 static struct slave *__vrf_find_slave_dev(struct slave_queue *queue,
 388                                           struct net_device *dev)
 389 {
 390         struct list_head *head = &queue->all_slaves;
 391         struct slave *slave;
 392
 393         list_for_each_entry(slave, head, list) {
 394                 if (slave->dev == dev)
 395                         return slave;
 396         }
 397
 398         return NULL;
 399 }
 400
 401 /* inverse of __vrf_insert_slave */
 402 static void __vrf_remove_slave(struct slave_queue *queue, struct slave *slave)
 403 {
 404         list_del(&slave->list);
 405 }
 406
 407 static void __vrf_insert_slave(struct slave_queue *queue, struct slave *slave)
 408 {
 409         list_add(&slave->list, &queue->all_slaves);
 410 }
 411
 412 static int do_vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 413 {
 414         struct slave *slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 415         struct net_vrf *vrf = netdev_priv(dev);
 416         struct slave_queue *queue = &vrf->queue;
 417         int ret = -ENOMEM;
 418
 419         if (!slave)
 420                 goto out_fail;
 421
 422         slave->dev = port_dev;
 423
 424         /* register the packet handler for slave ports */
 425         ret = netdev_rx_handler_register(port_dev, vrf_handle_frame, dev);
 426         if (ret) {
 427                 netdev_err(port_dev,
 428                            "Device %s failed to register rx_handler\n",
 429                            port_dev->name);
 430                 goto out_fail;
 431         }
 432
 433         ret = netdev_master_upper_dev_link(port_dev, dev);
 434         if (ret < 0)
 435                 goto out_unregister;
 436
 437         port_dev->priv_flags |= IFF_L3MDEV_SLAVE;
 438         __vrf_insert_slave(queue, slave);
 439         cycle_netdev(port_dev);
 440
 441         return 0;
 442
 443 out_unregister:
 444         netdev_rx_handler_unregister(port_dev);
 445 out_fail:
 446         kfree(slave);
 447         return ret;
 448 }
 449
 450 static int vrf_add_slave(struct net_device *dev, struct net_device *port_dev)
 451 {
 452         if (netif_is_l3_master(port_dev) || netif_is_l3_slave(port_dev))
 453                 return -EINVAL;
 454
 455         return do_vrf_add_slave(dev, port_dev);
 456 }
 457
 458 /* inverse of do_vrf_add_slave */
 459 static int do_vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 460 {
 461         struct net_vrf *vrf = netdev_priv(dev);
 462         struct slave_queue *queue = &vrf->queue;
 463         struct slave *slave;
 464
 465         netdev_upper_dev_unlink(port_dev, dev);
 466         port_dev->priv_flags &= ~IFF_L3MDEV_SLAVE;
 467
 468         netdev_rx_handler_unregister(port_dev);
 469
 470         cycle_netdev(port_dev);
 471
 472         slave = __vrf_find_slave_dev(queue, port_dev);
 473         if (slave)
 474                 __vrf_remove_slave(queue, slave);
 475
 476         kfree(slave);
 477
 478         return 0;
 479 }
 480
 481 static int vrf_del_slave(struct net_device *dev, struct net_device *port_dev)
 482 {
 483         return do_vrf_del_slave(dev, port_dev);
 484 }
 485
 486 static void vrf_dev_uninit(struct net_device *dev)
 487 {
 488         struct net_vrf *vrf = netdev_priv(dev);
 489         struct slave_queue *queue = &vrf->queue;
 490         struct list_head *head = &queue->all_slaves;
 491         struct slave *slave, *next;
 492
 493         vrf_rtable_destroy(vrf);
 494
 495         list_for_each_entry_safe(slave, next, head, list)
 496                 vrf_del_slave(dev, slave->dev);
 497
 498         free_percpu(dev->dstats);
 499         dev->dstats = NULL;
 500 }
 501
 502 static int vrf_dev_init(struct net_device *dev)
 503 {
 504         struct net_vrf *vrf = netdev_priv(dev);
 505
 506         INIT_LIST_HEAD(&vrf->queue.all_slaves);
 507
 508         dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
 509         if (!dev->dstats)
 510                 goto out_nomem;
 511
 512         /* create the default dst which points back to us */
 513         vrf->rth = vrf_rtable_create(dev);
 514         if (!vrf->rth)
 515                 goto out_stats;
 516
 517         dev->flags = IFF_MASTER | IFF_NOARP;
 518
 519         return 0;
 520
 521 out_stats:
 522         free_percpu(dev->dstats);
 523         dev->dstats = NULL;
 524 out_nomem:
 525         return -ENOMEM;
 526 }
 527
 528 static const struct net_device_ops vrf_netdev_ops = {
 529         .ndo_init               = vrf_dev_init,
 530         .ndo_uninit             = vrf_dev_uninit,
 531         .ndo_start_xmit         = vrf_xmit,
 532         .ndo_get_stats64        = vrf_get_stats64,
 533         .ndo_add_slave          = vrf_add_slave,
 534         .ndo_del_slave          = vrf_del_slave,
 535 };
 536
 537 static u32 vrf_fib_table(const struct net_device *dev)
 538 {
 539         struct net_vrf *vrf = netdev_priv(dev);
 540
 541         return vrf->tb_id;
 542 }
 543
 544 static struct rtable *vrf_get_rtable(const struct net_device *dev,
 545                                      const struct flowi4 *fl4)
 546 {
 547         struct rtable *rth = NULL;
 548
 549         if (!(fl4->flowi4_flags & FLOWI_FLAG_L3MDEV_SRC)) {
 550                 struct net_vrf *vrf = netdev_priv(dev);
 551
 552                 rth = vrf->rth;
 553                 atomic_inc(&rth->dst.__refcnt);
 554         }
 555
 556         return rth;
 557 }
 558
 559 /* called under rcu_read_lock */
 560 static void vrf_get_saddr(struct net_device *dev, struct flowi4 *fl4)
 561 {
 562         struct fib_result res = { .tclassid = 0 };
 563         struct net *net = dev_net(dev);
 564         u32 orig_tos = fl4->flowi4_tos;
 565         u8 flags = fl4->flowi4_flags;
 566         u8 scope = fl4->flowi4_scope;
 567         u8 tos = RT_FL_TOS(fl4);
 568
 569         if (unlikely(!fl4->daddr))
 570                 return;
 571
 572         fl4->flowi4_flags |= FLOWI_FLAG_SKIP_NH_OIF;
 573         fl4->flowi4_iif = LOOPBACK_IFINDEX;
 574         fl4->flowi4_tos = tos & IPTOS_RT_MASK;
 575         fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
 576                              RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
 577
 578         if (!fib_lookup(net, fl4, &res, 0)) {
 579                 if (res.type == RTN_LOCAL)
 580                         fl4->saddr = res.fi->fib_prefsrc ? : fl4->daddr;
 581                 else
 582                         fib_select_path(net, &res, fl4, -1);
 583         }
 584
 585         fl4->flowi4_flags = flags;
 586         fl4->flowi4_tos = orig_tos;
 587         fl4->flowi4_scope = scope;
 588 }
 589
 590 static const struct l3mdev_ops vrf_l3mdev_ops = {
 591         .l3mdev_fib_table       = vrf_fib_table,
 592         .l3mdev_get_rtable      = vrf_get_rtable,
 593         .l3mdev_get_saddr       = vrf_get_saddr,
 594 };
 595
 596 static void vrf_get_drvinfo(struct net_device *dev,
 597                             struct ethtool_drvinfo *info)
 598 {
 599         strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
 600         strlcpy(info->version, DRV_VERSION, sizeof(info->version));
 601 }
 602
 603 static const struct ethtool_ops vrf_ethtool_ops = {
 604         .get_drvinfo    = vrf_get_drvinfo,
 605 };
 606
 607 static void vrf_setup(struct net_device *dev)
 608 {
 609         ether_setup(dev);
 610
 611         /* Initialize the device structure. */
 612         dev->netdev_ops = &vrf_netdev_ops;
 613         dev->l3mdev_ops = &vrf_l3mdev_ops;
 614         dev->ethtool_ops = &vrf_ethtool_ops;
 615         dev->destructor = free_netdev;
 616
 617         /* Fill in device structure with ethernet-generic values. */
 618         eth_hw_addr_random(dev);
 619
 620         /* don't acquire vrf device's netif_tx_lock when transmitting */
 621         dev->features |= NETIF_F_LLTX;
 622
 623         /* don't allow vrf devices to change network namespaces. */
 624         dev->features |= NETIF_F_NETNS_LOCAL;
 625 }
 626
 627 static int vrf_validate(struct nlattr *tb[], struct nlattr *data[])
 628 {
 629         if (tb[IFLA_ADDRESS]) {
 630                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 631                         return -EINVAL;
 632                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 633                         return -EADDRNOTAVAIL;
 634         }
 635         return 0;
 636 }
 637
 638 static void vrf_dellink(struct net_device *dev, struct list_head *head)
 639 {
 640         unregister_netdevice_queue(dev, head);
 641 }
 642
 643 static int vrf_newlink(struct net *src_net, struct net_device *dev,
 644                        struct nlattr *tb[], struct nlattr *data[])
 645 {
 646         struct net_vrf *vrf = netdev_priv(dev);
 647         int err;
 648
 649         if (!data || !data[IFLA_VRF_TABLE])
 650                 return -EINVAL;
 651
 652         vrf->tb_id = nla_get_u32(data[IFLA_VRF_TABLE]);
 653
 654         dev->priv_flags |= IFF_L3MDEV_MASTER;
 655
 656         err = register_netdevice(dev);
 657         if (err < 0)
 658                 goto out_fail;
 659
 660         return 0;
 661
 662 out_fail:
 663         free_netdev(dev);
 664         return err;
 665 }
 666
 667 static size_t vrf_nl_getsize(const struct net_device *dev)
 668 {
 669         return nla_total_size(sizeof(u32));  /* IFLA_VRF_TABLE */
 670 }
 671
 672 static int vrf_fillinfo(struct sk_buff *skb,
 673                         const struct net_device *dev)
 674 {
 675         struct net_vrf *vrf = netdev_priv(dev);
 676
 677         return nla_put_u32(skb, IFLA_VRF_TABLE, vrf->tb_id);
 678 }
 679
 680 static const struct nla_policy vrf_nl_policy[IFLA_VRF_MAX + 1] = {
 681         [IFLA_VRF_TABLE] = { .type = NLA_U32 },
 682 };
 683
 684 static struct rtnl_link_ops vrf_link_ops __read_mostly = {
 685         .kind           = DRV_NAME,
 686         .priv_size      = sizeof(struct net_vrf),
 687
 688         .get_size       = vrf_nl_getsize,
 689         .policy         = vrf_nl_policy,
 690         .validate       = vrf_validate,
 691         .fill_info      = vrf_fillinfo,
 692
 693         .newlink        = vrf_newlink,
 694         .dellink        = vrf_dellink,
 695         .setup          = vrf_setup,
 696         .maxtype        = IFLA_VRF_MAX,
 697 };
 698
 699 static int vrf_device_event(struct notifier_block *unused,
 700                             unsigned long event, void *ptr)
 701 {
 702         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 703
 704         /* only care about unregister events to drop slave references */
 705         if (event == NETDEV_UNREGISTER) {
 706                 struct net_device *vrf_dev;
 707
 708                 if (!netif_is_l3_slave(dev))
 709                         goto out;
 710
 711                 vrf_dev = netdev_master_upper_dev_get(dev);
 712                 vrf_del_slave(vrf_dev, dev);
 713         }
 714 out:
 715         return NOTIFY_DONE;
 716 }
 717
 718 static struct notifier_block vrf_notifier_block __read_mostly = {
 719         .notifier_call = vrf_device_event,
 720 };
 721
 722 static int __init vrf_init_module(void)
 723 {
 724         int rc;
 725
 726         vrf_dst_ops.kmem_cachep =
 727                 kmem_cache_create("vrf_ip_dst_cache",
 728                                   sizeof(struct rtable), 0,
 729                                   SLAB_HWCACHE_ALIGN,
 730                                   NULL);
 731
 732         if (!vrf_dst_ops.kmem_cachep)
 733                 return -ENOMEM;
 734
 735         register_netdevice_notifier(&vrf_notifier_block);
 736
 737         rc = rtnl_link_register(&vrf_link_ops);
 738         if (rc < 0)
 739                 goto error;
 740
 741         return 0;
 742
 743 error:
 744         unregister_netdevice_notifier(&vrf_notifier_block);
 745         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 746         return rc;
 747 }
 748
 749 static void __exit vrf_cleanup_module(void)
 750 {
 751         rtnl_link_unregister(&vrf_link_ops);
 752         unregister_netdevice_notifier(&vrf_notifier_block);
 753         kmem_cache_destroy(vrf_dst_ops.kmem_cachep);
 754 }
 755
 756 module_init(vrf_init_module);
 757 module_exit(vrf_cleanup_module);
 758 MODULE_AUTHOR("Shrijeet Mukherjee, David Ahern");
 759 MODULE_DESCRIPTION("Device driver to instantiate VRF domains");
 760 MODULE_LICENSE("GPL");
 761 MODULE_ALIAS_RTNL_LINK(DRV_NAME);
 762 MODULE_VERSION(DRV_VERSION);