linux-stable/drivers/net/veth.c
Neil Horman 550fd08c2c net: Audit drivers to identify those needing IFF_TX_SKB_SHARING cleared
After the last patch, We are left in a state in which only drivers calling
ether_setup have IFF_TX_SKB_SHARING set (we assume that drivers touching real
hardware call ether_setup for their net_devices and don't hold any state in
their skbs.  There are a handful of drivers that violate this assumption of
course, and need to be fixed up.  This patch identifies those drivers, and marks
them as not being able to support the safe transmission of skbs by clearning the
IFF_TX_SKB_SHARING flag in priv_flags

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Karsten Keil <isdn@linux-pingi.de>
CC: "David S. Miller" <davem@davemloft.net>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Patrick McHardy <kaber@trash.net>
CC: Krzysztof Halasa <khc@pm.waw.pl>
CC: "John W. Linville" <linville@tuxdriver.com>
CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: Marcel Holtmann <marcel@holtmann.org>
CC: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-27 22:39:30 -07:00

457 lines
9.5 KiB
C

/*
* 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>
#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 veth_net_stats {
u64 rx_packets;
u64 tx_packets;
u64 rx_bytes;
u64 tx_bytes;
u64 rx_dropped;
struct u64_stats_sync syncp;
};
struct veth_priv {
struct net_device *peer;
struct veth_net_stats __percpu *stats;
};
/*
* 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)
{
strcpy(info->driver, DRV_NAME);
strcpy(info->version, DRV_VERSION);
strcpy(info->fw_version, "N/A");
}
static void veth_get_strings(struct net_device *dev, u32 stringset, u8 *buf)
{
switch(stringset) {
case ETH_SS_STATS:
memcpy(buf, &ethtool_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;
priv = netdev_priv(dev);
data[0] = priv->peer->ifindex;
}
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,
};
/*
* xmit
*/
static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct net_device *rcv = NULL;
struct veth_priv *priv, *rcv_priv;
struct veth_net_stats *stats, *rcv_stats;
int length;
priv = netdev_priv(dev);
rcv = priv->peer;
rcv_priv = netdev_priv(rcv);
stats = this_cpu_ptr(priv->stats);
rcv_stats = this_cpu_ptr(rcv_priv->stats);
/* 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;
length = skb->len;
if (dev_forward_skb(rcv, skb) != NET_RX_SUCCESS)
goto rx_drop;
u64_stats_update_begin(&stats->syncp);
stats->tx_bytes += length;
stats->tx_packets++;
u64_stats_update_end(&stats->syncp);
u64_stats_update_begin(&rcv_stats->syncp);
rcv_stats->rx_bytes += length;
rcv_stats->rx_packets++;
u64_stats_update_end(&rcv_stats->syncp);
return NETDEV_TX_OK;
rx_drop:
u64_stats_update_begin(&rcv_stats->syncp);
rcv_stats->rx_dropped++;
u64_stats_update_end(&rcv_stats->syncp);
return NETDEV_TX_OK;
}
/*
* general routines
*/
static struct rtnl_link_stats64 *veth_get_stats64(struct net_device *dev,
struct rtnl_link_stats64 *tot)
{
struct veth_priv *priv = netdev_priv(dev);
int cpu;
for_each_possible_cpu(cpu) {
struct veth_net_stats *stats = per_cpu_ptr(priv->stats, cpu);
u64 rx_packets, rx_bytes, rx_dropped;
u64 tx_packets, tx_bytes;
unsigned int start;
do {
start = u64_stats_fetch_begin_bh(&stats->syncp);
rx_packets = stats->rx_packets;
tx_packets = stats->tx_packets;
rx_bytes = stats->rx_bytes;
tx_bytes = stats->tx_bytes;
rx_dropped = stats->rx_dropped;
} while (u64_stats_fetch_retry_bh(&stats->syncp, start));
tot->rx_packets += rx_packets;
tot->tx_packets += tx_packets;
tot->rx_bytes += rx_bytes;
tot->tx_bytes += tx_bytes;
tot->rx_dropped += rx_dropped;
}
return tot;
}
static int veth_open(struct net_device *dev)
{
struct veth_priv *priv;
priv = netdev_priv(dev);
if (priv->peer == NULL)
return -ENOTCONN;
if (priv->peer->flags & IFF_UP) {
netif_carrier_on(dev);
netif_carrier_on(priv->peer);
}
return 0;
}
static int veth_close(struct net_device *dev)
{
struct veth_priv *priv = netdev_priv(dev);
netif_carrier_off(dev);
netif_carrier_off(priv->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)
{
struct veth_net_stats __percpu *stats;
struct veth_priv *priv;
stats = alloc_percpu(struct veth_net_stats);
if (stats == NULL)
return -ENOMEM;
priv = netdev_priv(dev);
priv->stats = stats;
return 0;
}
static void veth_dev_free(struct net_device *dev)
{
struct veth_priv *priv;
priv = netdev_priv(dev);
free_percpu(priv->stats);
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,
};
static void veth_setup(struct net_device *dev)
{
ether_setup(dev);
dev->priv_flags &= ~IFF_TX_SKB_SHARING;
dev->netdev_ops = &veth_netdev_ops;
dev->ethtool_ops = &veth_ethtool_ops;
dev->features |= NETIF_F_LLTX;
dev->destructor = veth_dev_free;
dev->hw_features = NETIF_F_NO_CSUM | NETIF_F_SG | NETIF_F_RXCSUM;
}
/*
* 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;
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 = nla_parse(peer_tb, IFLA_MAX,
nla_data(nla_peer) + sizeof(struct ifinfomsg),
nla_len(nla_peer) - sizeof(struct ifinfomsg),
ifla_policy);
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);
else
snprintf(ifname, IFNAMSIZ, DRV_NAME "%%d");
net = rtnl_link_get_net(src_net, tbp);
if (IS_ERR(net))
return PTR_ERR(net);
peer = rtnl_create_link(src_net, net, ifname, &veth_link_ops, tbp);
if (IS_ERR(peer)) {
put_net(net);
return PTR_ERR(peer);
}
if (tbp[IFLA_ADDRESS] == NULL)
random_ether_addr(peer->dev_addr);
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)
random_ether_addr(dev->dev_addr);
if (tb[IFLA_IFNAME])
nla_strlcpy(dev->name, tb[IFLA_IFNAME], IFNAMSIZ);
else
snprintf(dev->name, IFNAMSIZ, DRV_NAME "%%d");
if (strchr(dev->name, '%')) {
err = dev_alloc_name(dev, dev->name);
if (err < 0)
goto err_alloc_name;
}
err = register_netdevice(dev);
if (err < 0)
goto err_register_dev;
netif_carrier_off(dev);
/*
* tie the deviced together
*/
priv = netdev_priv(dev);
priv->peer = peer;
priv = netdev_priv(peer);
priv->peer = dev;
return 0;
err_register_dev:
/* nothing to do */
err_alloc_name:
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 = priv->peer;
unregister_netdevice_queue(dev, head);
unregister_netdevice_queue(peer, head);
}
static const struct nla_policy veth_policy[VETH_INFO_MAX + 1];
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,
};
/*
* 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);