diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/net/veth.c |
Initial import
Diffstat (limited to 'drivers/net/veth.c')
-rw-r--r-- | drivers/net/veth.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/drivers/net/veth.c b/drivers/net/veth.c new file mode 100644 index 000000000..c8186ffda --- /dev/null +++ b/drivers/net/veth.c @@ -0,0 +1,526 @@ +/* + * drivers/net/veth.c + * + * Copyright (C) 2007 OpenVZ http://openvz.org, SWsoft Inc + * + * Author: Pavel Emelianov <xemul@openvz.org> + * Ethtool interface from: Eric W. Biederman <ebiederm@xmission.com> + * + */ + +#include <linux/netdevice.h> +#include <linux/slab.h> +#include <linux/ethtool.h> +#include <linux/etherdevice.h> +#include <linux/u64_stats_sync.h> + +#include <net/rtnetlink.h> +#include <net/dst.h> +#include <net/xfrm.h> +#include <linux/veth.h> +#include <linux/module.h> + +#define DRV_NAME "veth" +#define DRV_VERSION "1.0" + +#define MIN_MTU 68 /* Min L3 MTU */ +#define MAX_MTU 65535 /* Max L3 MTU (arbitrary) */ + +struct pcpu_vstats { + u64 packets; + u64 bytes; + struct u64_stats_sync syncp; +}; + +struct veth_priv { + struct net_device __rcu *peer; + atomic64_t dropped; +}; + +/* + * ethtool interface + */ + +static struct { + const char string[ETH_GSTRING_LEN]; +} ethtool_stats_keys[] = { + { "peer_ifindex" }, +}; + +static int veth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd) +{ + cmd->supported = 0; + cmd->advertising = 0; + ethtool_cmd_speed_set(cmd, SPEED_10000); + cmd->duplex = DUPLEX_FULL; + cmd->port = PORT_TP; + cmd->phy_address = 0; + cmd->transceiver = XCVR_INTERNAL; + cmd->autoneg = AUTONEG_DISABLE; + cmd->maxtxpkt = 0; + cmd->maxrxpkt = 0; + return 0; +} + +static void veth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info) +{ + strlcpy(info->driver, DRV_NAME, sizeof(info->driver)); + strlcpy(info->version, DRV_VERSION, sizeof(info->version)); +} + +static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf) +{ + switch(stringset) { + case ETH_SS_STATS: + memcpy(buf, ðtool_stats_keys, sizeof(ethtool_stats_keys)); + break; + } +} + +static int veth_get_sset_count(struct net_device *dev, int sset) +{ + switch (sset) { + case ETH_SS_STATS: + return ARRAY_SIZE(ethtool_stats_keys); + default: + return -EOPNOTSUPP; + } +} + +static void veth_get_ethtool_stats(struct net_device *dev, + struct ethtool_stats *stats, u64 *data) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer = rtnl_dereference(priv->peer); + + data[0] = peer ? peer->ifindex : 0; +} + +static const struct ethtool_ops veth_ethtool_ops = { + .get_settings = veth_get_settings, + .get_drvinfo = veth_get_drvinfo, + .get_link = ethtool_op_get_link, + .get_strings = veth_get_strings, + .get_sset_count = veth_get_sset_count, + .get_ethtool_stats = veth_get_ethtool_stats, +}; + +static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *rcv; + int length = skb->len; + + rcu_read_lock(); + rcv = rcu_dereference(priv->peer); + if (unlikely(!rcv)) { + kfree_skb(skb); + goto drop; + } + /* don't change ip_summed == CHECKSUM_PARTIAL, as that + * will cause bad checksum on forwarded packets + */ + if (skb->ip_summed == CHECKSUM_NONE && + rcv->features & NETIF_F_RXCSUM) + skb->ip_summed = CHECKSUM_UNNECESSARY; + + if (likely(dev_forward_skb(rcv, skb) == NET_RX_SUCCESS)) { + struct pcpu_vstats *stats = this_cpu_ptr(dev->vstats); + + u64_stats_update_begin(&stats->syncp); + stats->bytes += length; + stats->packets++; + u64_stats_update_end(&stats->syncp); + } else { +drop: + atomic64_inc(&priv->dropped); + } + rcu_read_unlock(); + return NETDEV_TX_OK; +} + +/* + * general routines + */ + +static u64 veth_stats_one(struct pcpu_vstats *result, struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + int cpu; + + result->packets = 0; + result->bytes = 0; + for_each_possible_cpu(cpu) { + struct pcpu_vstats *stats = per_cpu_ptr(dev->vstats, cpu); + u64 packets, bytes; + unsigned int start; + + do { + start = u64_stats_fetch_begin_irq(&stats->syncp); + packets = stats->packets; + bytes = stats->bytes; + } while (u64_stats_fetch_retry_irq(&stats->syncp, start)); + result->packets += packets; + result->bytes += bytes; + } + return atomic64_read(&priv->dropped); +} + +static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev, + struct rtnl_link_stats64 *tot) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer; + struct pcpu_vstats one; + + tot->tx_dropped = veth_stats_one(&one, dev); + tot->tx_bytes = one.bytes; + tot->tx_packets = one.packets; + + rcu_read_lock(); + peer = rcu_dereference(priv->peer); + if (peer) { + tot->rx_dropped = veth_stats_one(&one, peer); + tot->rx_bytes = one.bytes; + tot->rx_packets = one.packets; + } + rcu_read_unlock(); + + return tot; +} + +/* fake multicast ability */ +static void veth_set_multicast_list(struct net_device *dev) +{ +} + +static int veth_open(struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer = rtnl_dereference(priv->peer); + + if (!peer) + return -ENOTCONN; + + if (peer->flags & IFF_UP) { + netif_carrier_on(dev); + netif_carrier_on(peer); + } + return 0; +} + +static int veth_close(struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer = rtnl_dereference(priv->peer); + + netif_carrier_off(dev); + if (peer) + netif_carrier_off(peer); + + return 0; +} + +static int is_valid_veth_mtu(int new_mtu) +{ + return new_mtu >= MIN_MTU && new_mtu <= MAX_MTU; +} + +static int veth_change_mtu(struct net_device *dev, int new_mtu) +{ + if (!is_valid_veth_mtu(new_mtu)) + return -EINVAL; + dev->mtu = new_mtu; + return 0; +} + +static int veth_dev_init(struct net_device *dev) +{ + dev->vstats = netdev_alloc_pcpu_stats(struct pcpu_vstats); + if (!dev->vstats) + return -ENOMEM; + return 0; +} + +static void veth_dev_free(struct net_device *dev) +{ + free_percpu(dev->vstats); + free_netdev(dev); +} + +#ifdef CONFIG_NET_POLL_CONTROLLER +static void veth_poll_controller(struct net_device *dev) +{ + /* veth only receives frames when its peer sends one + * Since it's a synchronous operation, we are guaranteed + * never to have pending data when we poll for it so + * there is nothing to do here. + * + * We need this though so netpoll recognizes us as an interface that + * supports polling, which enables bridge devices in virt setups to + * still use netconsole + */ +} +#endif /* CONFIG_NET_POLL_CONTROLLER */ + +static int veth_get_iflink(const struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer; + int iflink; + + rcu_read_lock(); + peer = rcu_dereference(priv->peer); + iflink = peer ? peer->ifindex : 0; + rcu_read_unlock(); + + return iflink; +} + +static const struct net_device_ops veth_netdev_ops = { + .ndo_init = veth_dev_init, + .ndo_open = veth_open, + .ndo_stop = veth_close, + .ndo_start_xmit = veth_xmit, + .ndo_change_mtu = veth_change_mtu, + .ndo_get_stats64 = veth_get_stats64, + .ndo_set_rx_mode = veth_set_multicast_list, + .ndo_set_mac_address = eth_mac_addr, +#ifdef CONFIG_NET_POLL_CONTROLLER + .ndo_poll_controller = veth_poll_controller, +#endif + .ndo_get_iflink = veth_get_iflink, +}; + +#define VETH_FEATURES (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \ + NETIF_F_HW_CSUM | NETIF_F_RXCSUM | NETIF_F_HIGHDMA | \ + NETIF_F_GSO_GRE | NETIF_F_GSO_UDP_TUNNEL | \ + NETIF_F_GSO_IPIP | NETIF_F_GSO_SIT | NETIF_F_UFO | \ + NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX | \ + NETIF_F_HW_VLAN_STAG_TX | NETIF_F_HW_VLAN_STAG_RX ) + +static void veth_setup(struct net_device *dev) +{ + ether_setup(dev); + + dev->priv_flags &= ~IFF_TX_SKB_SHARING; + dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; + + dev->netdev_ops = &veth_netdev_ops; + dev->ethtool_ops = &veth_ethtool_ops; + dev->features |= NETIF_F_LLTX; + dev->features |= VETH_FEATURES; + dev->vlan_features = dev->features & + ~(NETIF_F_HW_VLAN_CTAG_TX | + NETIF_F_HW_VLAN_STAG_TX | + NETIF_F_HW_VLAN_CTAG_RX | + NETIF_F_HW_VLAN_STAG_RX); + dev->destructor = veth_dev_free; + + dev->hw_features = VETH_FEATURES; + dev->hw_enc_features = VETH_FEATURES; +} + +/* + * netlink interface + */ + +static int veth_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + if (tb[IFLA_ADDRESS]) { + if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) + return -EINVAL; + if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) + return -EADDRNOTAVAIL; + } + if (tb[IFLA_MTU]) { + if (!is_valid_veth_mtu(nla_get_u32(tb[IFLA_MTU]))) + return -EINVAL; + } + return 0; +} + +static struct rtnl_link_ops veth_link_ops; + +static int veth_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[]) +{ + int err; + struct net_device *peer; + struct veth_priv *priv; + char ifname[IFNAMSIZ]; + struct nlattr *peer_tb[IFLA_MAX + 1], **tbp; + unsigned char name_assign_type; + struct ifinfomsg *ifmp; + struct net *net; + + /* + * create and register peer first + */ + if (data != NULL && data[VETH_INFO_PEER] != NULL) { + struct nlattr *nla_peer; + + nla_peer = data[VETH_INFO_PEER]; + ifmp = nla_data(nla_peer); + err = rtnl_nla_parse_ifla(peer_tb, + nla_data(nla_peer) + sizeof(struct ifinfomsg), + nla_len(nla_peer) - sizeof(struct ifinfomsg)); + if (err < 0) + return err; + + err = veth_validate(peer_tb, NULL); + if (err < 0) + return err; + + tbp = peer_tb; + } else { + ifmp = NULL; + tbp = tb; + } + + if (tbp[IFLA_IFNAME]) { + nla_strlcpy(ifname, tbp[IFLA_IFNAME], IFNAMSIZ); + name_assign_type = NET_NAME_USER; + } else { + snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d"); + name_assign_type = NET_NAME_ENUM; + } + + net = rtnl_link_get_net(src_net, tbp); + if (IS_ERR(net)) + return PTR_ERR(net); + + peer = rtnl_create_link(net, ifname, name_assign_type, + &veth_link_ops, tbp); + if (IS_ERR(peer)) { + put_net(net); + return PTR_ERR(peer); + } + + if (tbp[IFLA_ADDRESS] == NULL) + eth_hw_addr_random(peer); + + if (ifmp && (dev->ifindex != 0)) + peer->ifindex = ifmp->ifi_index; + + err = register_netdevice(peer); + put_net(net); + net = NULL; + if (err < 0) + goto err_register_peer; + + netif_carrier_off(peer); + + err = rtnl_configure_link(peer, ifmp); + if (err < 0) + goto err_configure_peer; + + /* + * register dev last + * + * note, that since we've registered new device the dev's name + * should be re-allocated + */ + + if (tb[IFLA_ADDRESS] == NULL) + eth_hw_addr_random(dev); + + if (tb[IFLA_IFNAME]) + nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ); + else + snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d"); + + err = register_netdevice(dev); + if (err < 0) + goto err_register_dev; + + netif_carrier_off(dev); + + /* + * tie the deviced together + */ + + priv = netdev_priv(dev); + rcu_assign_pointer(priv->peer, peer); + + priv = netdev_priv(peer); + rcu_assign_pointer(priv->peer, dev); + return 0; + +err_register_dev: + /* nothing to do */ +err_configure_peer: + unregister_netdevice(peer); + return err; + +err_register_peer: + free_netdev(peer); + return err; +} + +static void veth_dellink(struct net_device *dev, struct list_head *head) +{ + struct veth_priv *priv; + struct net_device *peer; + + priv = netdev_priv(dev); + peer = rtnl_dereference(priv->peer); + + /* Note : dellink() is called from default_device_exit_batch(), + * before a rcu_synchronize() point. The devices are guaranteed + * not being freed before one RCU grace period. + */ + RCU_INIT_POINTER(priv->peer, NULL); + unregister_netdevice_queue(dev, head); + + if (peer) { + priv = netdev_priv(peer); + RCU_INIT_POINTER(priv->peer, NULL); + unregister_netdevice_queue(peer, head); + } +} + +static const struct nla_policy veth_policy[VETH_INFO_MAX + 1] = { + [VETH_INFO_PEER] = { .len = sizeof(struct ifinfomsg) }, +}; + +static struct net *veth_get_link_net(const struct net_device *dev) +{ + struct veth_priv *priv = netdev_priv(dev); + struct net_device *peer = rtnl_dereference(priv->peer); + + return peer ? dev_net(peer) : dev_net(dev); +} + +static struct rtnl_link_ops veth_link_ops = { + .kind = DRV_NAME, + .priv_size = sizeof(struct veth_priv), + .setup = veth_setup, + .validate = veth_validate, + .newlink = veth_newlink, + .dellink = veth_dellink, + .policy = veth_policy, + .maxtype = VETH_INFO_MAX, + .get_link_net = veth_get_link_net, +}; + +/* + * init/fini + */ + +static __init int veth_init(void) +{ + return rtnl_link_register(&veth_link_ops); +} + +static __exit void veth_exit(void) +{ + rtnl_link_unregister(&veth_link_ops); +} + +module_init(veth_init); +module_exit(veth_exit); + +MODULE_DESCRIPTION("Virtual Ethernet Tunnel"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS_RTNL_LINK(DRV_NAME); |