veth.c revision 3600cdadb7ab9ee5f4e73ed01242c3e8b8e3282c
1/* 2 * drivers/net/veth.c 3 * 4 * Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc 5 * 6 * Author: Pavel Emelianov <xemul@openvz.org> 7 * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com> 8 * 9 */ 10 11#include <linux/netdevice.h> 12#include <linux/slab.h> 13#include <linux/ethtool.h> 14#include <linux/etherdevice.h> 15#include <linux/u64_stats_sync.h> 16 17#include <net/dst.h> 18#include <net/xfrm.h> 19#include <linux/veth.h> 20 21#define DRV_NAME "veth" 22#define DRV_VERSION "1.0" 23 24#define MIN_MTU 68 /* Min L3 MTU */ 25#define MAX_MTU 65535 /* Max L3 MTU (arbitrary) */ 26 27struct veth_net_stats { 28 u64 rx_packets; 29 u64 tx_packets; 30 u64 rx_bytes; 31 u64 tx_bytes; 32 u64 rx_dropped; 33 u64 tx_dropped; 34 struct u64_stats_sync syncp; 35}; 36 37struct veth_priv { 38 struct net_device *peer; 39 struct veth_net_stats __percpu *stats; 40}; 41 42/* 43 * ethtool interface 44 */ 45 46static struct { 47 const char string[ETH_GSTRING_LEN]; 48} ethtool_stats_keys[] = { 49 { "peer_ifindex" }, 50}; 51 52static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) 53{ 54 cmd->supported = 0; 55 cmd->advertising = 0; 56 ethtool_cmd_speed_set(cmd, SPEED_10000); 57 cmd->duplex = DUPLEX_FULL; 58 cmd->port = PORT_TP; 59 cmd->phy_address = 0; 60 cmd->transceiver = XCVR_INTERNAL; 61 cmd->autoneg = AUTONEG_DISABLE; 62 cmd->maxtxpkt = 0; 63 cmd->maxrxpkt = 0; 64 return 0; 65} 66 67static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) 68{ 69 strcpy(info->driver, DRV_NAME); 70 strcpy(info->version, DRV_VERSION); 71 strcpy(info->fw_version, "N/A"); 72} 73 74static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf) 75{ 76 switch(stringset) { 77 case ETH_SS_STATS: 78 memcpy(buf, ðtool_stats_keys, sizeof(ethtool_stats_keys)); 79 break; 80 } 81} 82 83static int veth_get_sset_count(struct net_device *dev, int sset) 84{ 85 switch (sset) { 86 case ETH_SS_STATS: 87 return ARRAY_SIZE(ethtool_stats_keys); 88 default: 89 return -EOPNOTSUPP; 90 } 91} 92 93static void veth_get_ethtool_stats(struct net_device *dev, 94 struct ethtool_stats *stats, u64 *data) 95{ 96 struct veth_priv *priv; 97 98 priv = netdev_priv(dev); 99 data[0] = priv->peer->ifindex; 100} 101 102static const struct ethtool_ops veth_ethtool_ops = { 103 .get_settings = veth_get_settings, 104 .get_drvinfo = veth_get_drvinfo, 105 .get_link = ethtool_op_get_link, 106 .get_strings = veth_get_strings, 107 .get_sset_count = veth_get_sset_count, 108 .get_ethtool_stats = veth_get_ethtool_stats, 109}; 110 111/* 112 * xmit 113 */ 114 115static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev) 116{ 117 struct net_device *rcv = NULL; 118 struct veth_priv *priv, *rcv_priv; 119 struct veth_net_stats *stats, *rcv_stats; 120 int length; 121 122 priv = netdev_priv(dev); 123 rcv = priv->peer; 124 rcv_priv = netdev_priv(rcv); 125 126 stats = this_cpu_ptr(priv->stats); 127 rcv_stats = this_cpu_ptr(rcv_priv->stats); 128 129 /* don't change ip_summed == CHECKSUM_PARTIAL, as that 130 will cause bad checksum on forwarded packets */ 131 if (skb->ip_summed == CHECKSUM_NONE && 132 rcv->features & NETIF_F_RXCSUM) 133 skb->ip_summed = CHECKSUM_UNNECESSARY; 134 135 length = skb->len; 136 if (dev_forward_skb(rcv, skb) != NET_RX_SUCCESS) 137 goto rx_drop; 138 139 u64_stats_update_begin(&stats->syncp); 140 stats->tx_bytes += length; 141 stats->tx_packets++; 142 u64_stats_update_end(&stats->syncp); 143 144 u64_stats_update_begin(&rcv_stats->syncp); 145 rcv_stats->rx_bytes += length; 146 rcv_stats->rx_packets++; 147 u64_stats_update_end(&rcv_stats->syncp); 148 149 return NETDEV_TX_OK; 150 151rx_drop: 152 u64_stats_update_begin(&rcv_stats->syncp); 153 rcv_stats->rx_dropped++; 154 u64_stats_update_end(&rcv_stats->syncp); 155 return NETDEV_TX_OK; 156} 157 158/* 159 * general routines 160 */ 161 162static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev, 163 struct rtnl_link_stats64 *tot) 164{ 165 struct veth_priv *priv = netdev_priv(dev); 166 int cpu; 167 168 for_each_possible_cpu(cpu) { 169 struct veth_net_stats *stats = per_cpu_ptr(priv->stats, cpu); 170 u64 rx_packets, rx_bytes, rx_dropped; 171 u64 tx_packets, tx_bytes, tx_dropped; 172 unsigned int start; 173 174 do { 175 start = u64_stats_fetch_begin_bh(&stats->syncp); 176 rx_packets = stats->rx_packets; 177 tx_packets = stats->tx_packets; 178 rx_bytes = stats->rx_bytes; 179 tx_bytes = stats->tx_bytes; 180 rx_dropped = stats->rx_dropped; 181 tx_dropped = stats->tx_dropped; 182 } while (u64_stats_fetch_retry_bh(&stats->syncp, start)); 183 tot->rx_packets += rx_packets; 184 tot->tx_packets += tx_packets; 185 tot->rx_bytes += rx_bytes; 186 tot->tx_bytes += tx_bytes; 187 tot->rx_dropped += rx_dropped; 188 tot->tx_dropped += tx_dropped; 189 } 190 191 return tot; 192} 193 194static int veth_open(struct net_device *dev) 195{ 196 struct veth_priv *priv; 197 198 priv = netdev_priv(dev); 199 if (priv->peer == NULL) 200 return -ENOTCONN; 201 202 if (priv->peer->flags & IFF_UP) { 203 netif_carrier_on(dev); 204 netif_carrier_on(priv->peer); 205 } 206 return 0; 207} 208 209static int veth_close(struct net_device *dev) 210{ 211 struct veth_priv *priv = netdev_priv(dev); 212 213 netif_carrier_off(dev); 214 netif_carrier_off(priv->peer); 215 216 return 0; 217} 218 219static int is_valid_veth_mtu(int new_mtu) 220{ 221 return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU; 222} 223 224static int veth_change_mtu(struct net_device *dev, int new_mtu) 225{ 226 if (!is_valid_veth_mtu(new_mtu)) 227 return -EINVAL; 228 dev->mtu = new_mtu; 229 return 0; 230} 231 232static int veth_dev_init(struct net_device *dev) 233{ 234 struct veth_net_stats __percpu *stats; 235 struct veth_priv *priv; 236 237 stats = alloc_percpu(struct veth_net_stats); 238 if (stats == NULL) 239 return -ENOMEM; 240 241 priv = netdev_priv(dev); 242 priv->stats = stats; 243 return 0; 244} 245 246static void veth_dev_free(struct net_device *dev) 247{ 248 struct veth_priv *priv; 249 250 priv = netdev_priv(dev); 251 free_percpu(priv->stats); 252 free_netdev(dev); 253} 254 255static const struct net_device_ops veth_netdev_ops = { 256 .ndo_init = veth_dev_init, 257 .ndo_open = veth_open, 258 .ndo_stop = veth_close, 259 .ndo_start_xmit = veth_xmit, 260 .ndo_change_mtu = veth_change_mtu, 261 .ndo_get_stats64 = veth_get_stats64, 262 .ndo_set_mac_address = eth_mac_addr, 263}; 264 265static void veth_setup(struct net_device *dev) 266{ 267 ether_setup(dev); 268 269 dev->netdev_ops = &veth_netdev_ops; 270 dev->ethtool_ops = &veth_ethtool_ops; 271 dev->features |= NETIF_F_LLTX; 272 dev->destructor = veth_dev_free; 273 274 dev->hw_features = NETIF_F_NO_CSUM | NETIF_F_SG | NETIF_F_RXCSUM; 275} 276 277/* 278 * netlink interface 279 */ 280 281static int veth_validate(struct nlattr *tb[], struct nlattr *data[]) 282{ 283 if (tb[IFLA_ADDRESS]) { 284 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 285 return -EINVAL; 286 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 287 return -EADDRNOTAVAIL; 288 } 289 if (tb[IFLA_MTU]) { 290 if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU]))) 291 return -EINVAL; 292 } 293 return 0; 294} 295 296static struct rtnl_link_ops veth_link_ops; 297 298static int veth_newlink(struct net *src_net, struct net_device *dev, 299 struct nlattr *tb[], struct nlattr *data[]) 300{ 301 int err; 302 struct net_device *peer; 303 struct veth_priv *priv; 304 char ifname[IFNAMSIZ]; 305 struct nlattr *peer_tb[IFLA_MAX + 1], **tbp; 306 struct ifinfomsg *ifmp; 307 struct net *net; 308 309 /* 310 * create and register peer first 311 */ 312 if (data != NULL && data[VETH_INFO_PEER] != NULL) { 313 struct nlattr *nla_peer; 314 315 nla_peer = data[VETH_INFO_PEER]; 316 ifmp = nla_data(nla_peer); 317 err = nla_parse(peer_tb, IFLA_MAX, 318 nla_data(nla_peer) + sizeof(struct ifinfomsg), 319 nla_len(nla_peer) - sizeof(struct ifinfomsg), 320 ifla_policy); 321 if (err < 0) 322 return err; 323 324 err = veth_validate(peer_tb, NULL); 325 if (err < 0) 326 return err; 327 328 tbp = peer_tb; 329 } else { 330 ifmp = NULL; 331 tbp = tb; 332 } 333 334 if (tbp[IFLA_IFNAME]) 335 nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ); 336 else 337 snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d"); 338 339 net = rtnl_link_get_net(src_net, tbp); 340 if (IS_ERR(net)) 341 return PTR_ERR(net); 342 343 peer = rtnl_create_link(src_net, net, ifname, &veth_link_ops, tbp); 344 if (IS_ERR(peer)) { 345 put_net(net); 346 return PTR_ERR(peer); 347 } 348 349 if (tbp[IFLA_ADDRESS] == NULL) 350 random_ether_addr(peer->dev_addr); 351 352 err = register_netdevice(peer); 353 put_net(net); 354 net = NULL; 355 if (err < 0) 356 goto err_register_peer; 357 358 netif_carrier_off(peer); 359 360 err = rtnl_configure_link(peer, ifmp); 361 if (err < 0) 362 goto err_configure_peer; 363 364 /* 365 * register dev last 366 * 367 * note, that since we've registered new device the dev's name 368 * should be re-allocated 369 */ 370 371 if (tb[IFLA_ADDRESS] == NULL) 372 random_ether_addr(dev->dev_addr); 373 374 if (tb[IFLA_IFNAME]) 375 nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ); 376 else 377 snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d"); 378 379 if (strchr(dev->name, '%')) { 380 err = dev_alloc_name(dev, dev->name); 381 if (err < 0) 382 goto err_alloc_name; 383 } 384 385 err = register_netdevice(dev); 386 if (err < 0) 387 goto err_register_dev; 388 389 netif_carrier_off(dev); 390 391 /* 392 * tie the deviced together 393 */ 394 395 priv = netdev_priv(dev); 396 priv->peer = peer; 397 398 priv = netdev_priv(peer); 399 priv->peer = dev; 400 return 0; 401 402err_register_dev: 403 /* nothing to do */ 404err_alloc_name: 405err_configure_peer: 406 unregister_netdevice(peer); 407 return err; 408 409err_register_peer: 410 free_netdev(peer); 411 return err; 412} 413 414static void veth_dellink(struct net_device *dev, struct list_head *head) 415{ 416 struct veth_priv *priv; 417 struct net_device *peer; 418 419 priv = netdev_priv(dev); 420 peer = priv->peer; 421 422 unregister_netdevice_queue(dev, head); 423 unregister_netdevice_queue(peer, head); 424} 425 426static const struct nla_policy veth_policy[VETH_INFO_MAX + 1]; 427 428static struct rtnl_link_ops veth_link_ops = { 429 .kind = DRV_NAME, 430 .priv_size = sizeof(struct veth_priv), 431 .setup = veth_setup, 432 .validate = veth_validate, 433 .newlink = veth_newlink, 434 .dellink = veth_dellink, 435 .policy = veth_policy, 436 .maxtype = VETH_INFO_MAX, 437}; 438 439/* 440 * init/fini 441 */ 442 443static __init int veth_init(void) 444{ 445 return rtnl_link_register(&veth_link_ops); 446} 447 448static __exit void veth_exit(void) 449{ 450 rtnl_link_unregister(&veth_link_ops); 451} 452 453module_init(veth_init); 454module_exit(veth_exit); 455 456MODULE_DESCRIPTION("Virtual Ethernet Tunnel"); 457MODULE_LICENSE("GPL v2"); 458MODULE_ALIAS_RTNL_LINK(DRV_NAME); 459