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|
/*
* 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/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_bh(&stats->syncp);
packets = stats->packets;
bytes = stats->bytes;
} while (u64_stats_fetch_retry_bh(&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;
}
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 = alloc_percpu(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);
}
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_mac_address = eth_mac_addr,
};
#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_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
|