linux/net/bridge/br_device.c
stephen hemminger 1faa4356a3 bridge: control carrier based on ports online
This makes the bridge device behave like a physical device.
In earlier releases the bridge always asserted carrier. This
changes the behavior so that bridge device carrier is on only
if one or more ports are in the forwarding state. This
should help IPv6 autoconfiguration, DHCP, and routing daemons.

I did brief testing with Network and Virt manager and they
seem fine, but since this changes behavior of bridge, it should
wait until net-next (2.6.39).

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Tested-By: Adam Majer <adamm@zombino.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-14 14:29:02 -07:00

375 lines
8.1 KiB
C

/*
* Device handling code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/netpoll.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/list.h>
#include <linux/netfilter_bridge.h>
#include <asm/uaccess.h>
#include "br_private.h"
/* net device transmit always called with BH disabled */
netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
const unsigned char *dest = skb->data;
struct net_bridge_fdb_entry *dst;
struct net_bridge_mdb_entry *mdst;
struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats);
#ifdef CONFIG_BRIDGE_NETFILTER
if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
br_nf_pre_routing_finish_bridge_slow(skb);
return NETDEV_TX_OK;
}
#endif
u64_stats_update_begin(&brstats->syncp);
brstats->tx_packets++;
brstats->tx_bytes += skb->len;
u64_stats_update_end(&brstats->syncp);
BR_INPUT_SKB_CB(skb)->brdev = dev;
skb_reset_mac_header(skb);
skb_pull(skb, ETH_HLEN);
rcu_read_lock();
if (is_multicast_ether_addr(dest)) {
if (unlikely(netpoll_tx_running(dev))) {
br_flood_deliver(br, skb);
goto out;
}
if (br_multicast_rcv(br, NULL, skb)) {
kfree_skb(skb);
goto out;
}
mdst = br_mdb_get(br, skb);
if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb))
br_multicast_deliver(mdst, skb);
else
br_flood_deliver(br, skb);
} else if ((dst = __br_fdb_get(br, dest)) != NULL)
br_deliver(dst->dst, skb);
else
br_flood_deliver(br, skb);
out:
rcu_read_unlock();
return NETDEV_TX_OK;
}
static int br_dev_open(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
netif_carrier_off(dev);
br_features_recompute(br);
netif_start_queue(dev);
br_stp_enable_bridge(br);
br_multicast_open(br);
return 0;
}
static void br_dev_set_multicast_list(struct net_device *dev)
{
}
static int br_dev_stop(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
netif_carrier_off(dev);
br_stp_disable_bridge(br);
br_multicast_stop(br);
netif_stop_queue(dev);
return 0;
}
static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev,
struct rtnl_link_stats64 *stats)
{
struct net_bridge *br = netdev_priv(dev);
struct br_cpu_netstats tmp, sum = { 0 };
unsigned int cpu;
for_each_possible_cpu(cpu) {
unsigned int start;
const struct br_cpu_netstats *bstats
= per_cpu_ptr(br->stats, cpu);
do {
start = u64_stats_fetch_begin(&bstats->syncp);
memcpy(&tmp, bstats, sizeof(tmp));
} while (u64_stats_fetch_retry(&bstats->syncp, start));
sum.tx_bytes += tmp.tx_bytes;
sum.tx_packets += tmp.tx_packets;
sum.rx_bytes += tmp.rx_bytes;
sum.rx_packets += tmp.rx_packets;
}
stats->tx_bytes = sum.tx_bytes;
stats->tx_packets = sum.tx_packets;
stats->rx_bytes = sum.rx_bytes;
stats->rx_packets = sum.rx_packets;
return stats;
}
static int br_change_mtu(struct net_device *dev, int new_mtu)
{
struct net_bridge *br = netdev_priv(dev);
if (new_mtu < 68 || new_mtu > br_min_mtu(br))
return -EINVAL;
dev->mtu = new_mtu;
#ifdef CONFIG_BRIDGE_NETFILTER
/* remember the MTU in the rtable for PMTU */
dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu);
#endif
return 0;
}
/* Allow setting mac address to any valid ethernet address. */
static int br_set_mac_address(struct net_device *dev, void *p)
{
struct net_bridge *br = netdev_priv(dev);
struct sockaddr *addr = p;
if (!is_valid_ether_addr(addr->sa_data))
return -EINVAL;
spin_lock_bh(&br->lock);
memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
br_stp_change_bridge_id(br, addr->sa_data);
br->flags |= BR_SET_MAC_ADDR;
spin_unlock_bh(&br->lock);
return 0;
}
static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
{
strcpy(info->driver, "bridge");
strcpy(info->version, BR_VERSION);
strcpy(info->fw_version, "N/A");
strcpy(info->bus_info, "N/A");
}
static int br_set_sg(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_SG;
else
br->feature_mask &= ~NETIF_F_SG;
br_features_recompute(br);
return 0;
}
static int br_set_tso(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_TSO;
else
br->feature_mask &= ~NETIF_F_TSO;
br_features_recompute(br);
return 0;
}
static int br_set_tx_csum(struct net_device *dev, u32 data)
{
struct net_bridge *br = netdev_priv(dev);
if (data)
br->feature_mask |= NETIF_F_NO_CSUM;
else
br->feature_mask &= ~NETIF_F_ALL_CSUM;
br_features_recompute(br);
return 0;
}
static int br_set_flags(struct net_device *netdev, u32 data)
{
return ethtool_op_set_flags(netdev, data, ETH_FLAG_TXVLAN);
}
#ifdef CONFIG_NET_POLL_CONTROLLER
static void br_poll_controller(struct net_device *br_dev)
{
}
static void br_netpoll_cleanup(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
struct net_bridge_port *p, *n;
list_for_each_entry_safe(p, n, &br->port_list, list) {
br_netpoll_disable(p);
}
}
static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
{
struct net_bridge *br = netdev_priv(dev);
struct net_bridge_port *p, *n;
int err = 0;
list_for_each_entry_safe(p, n, &br->port_list, list) {
if (!p->dev)
continue;
err = br_netpoll_enable(p);
if (err)
goto fail;
}
out:
return err;
fail:
br_netpoll_cleanup(dev);
goto out;
}
int br_netpoll_enable(struct net_bridge_port *p)
{
struct netpoll *np;
int err = 0;
np = kzalloc(sizeof(*p->np), GFP_KERNEL);
err = -ENOMEM;
if (!np)
goto out;
np->dev = p->dev;
err = __netpoll_setup(np);
if (err) {
kfree(np);
goto out;
}
p->np = np;
out:
return err;
}
void br_netpoll_disable(struct net_bridge_port *p)
{
struct netpoll *np = p->np;
if (!np)
return;
p->np = NULL;
/* Wait for transmitting packets to finish before freeing. */
synchronize_rcu_bh();
__netpoll_cleanup(np);
kfree(np);
}
#endif
static int br_add_slave(struct net_device *dev, struct net_device *slave_dev)
{
struct net_bridge *br = netdev_priv(dev);
return br_add_if(br, slave_dev);
}
static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
{
struct net_bridge *br = netdev_priv(dev);
return br_del_if(br, slave_dev);
}
static const struct ethtool_ops br_ethtool_ops = {
.get_drvinfo = br_getinfo,
.get_link = ethtool_op_get_link,
.get_tx_csum = ethtool_op_get_tx_csum,
.set_tx_csum = br_set_tx_csum,
.get_sg = ethtool_op_get_sg,
.set_sg = br_set_sg,
.get_tso = ethtool_op_get_tso,
.set_tso = br_set_tso,
.get_ufo = ethtool_op_get_ufo,
.set_ufo = ethtool_op_set_ufo,
.get_flags = ethtool_op_get_flags,
.set_flags = br_set_flags,
};
static const struct net_device_ops br_netdev_ops = {
.ndo_open = br_dev_open,
.ndo_stop = br_dev_stop,
.ndo_start_xmit = br_dev_xmit,
.ndo_get_stats64 = br_get_stats64,
.ndo_set_mac_address = br_set_mac_address,
.ndo_set_multicast_list = br_dev_set_multicast_list,
.ndo_change_mtu = br_change_mtu,
.ndo_do_ioctl = br_dev_ioctl,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_netpoll_setup = br_netpoll_setup,
.ndo_netpoll_cleanup = br_netpoll_cleanup,
.ndo_poll_controller = br_poll_controller,
#endif
.ndo_add_slave = br_add_slave,
.ndo_del_slave = br_del_slave,
};
static void br_dev_free(struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
free_percpu(br->stats);
free_netdev(dev);
}
void br_dev_setup(struct net_device *dev)
{
random_ether_addr(dev->dev_addr);
ether_setup(dev);
dev->netdev_ops = &br_netdev_ops;
dev->destructor = br_dev_free;
SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
dev->tx_queue_len = 0;
dev->priv_flags = IFF_EBRIDGE;
dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
NETIF_F_NETNS_LOCAL | NETIF_F_GSO | NETIF_F_HW_VLAN_TX;
}