net/bridge/br_device.c - arm/linux-arm64-legacy - Git at Google

 /*
  *	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 no BH (preempt_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);

 	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))
 			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:
 	return NETDEV_TX_OK;
 }

 static int br_dev_open(struct net_device *dev)
 {
 	struct net_bridge *br = netdev_priv(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);

 	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 */
 	br->fake_rtable.dst.metrics[RTAX_MTU - 1] = 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;
 }

 #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 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,
 };

 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
 };

 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;
 }
	/*
	* 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 no BH (preempt_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);

	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))
	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:
	return NETDEV_TX_OK;
	}

	static int br_dev_open(struct net_device *dev)
	{
	struct net_bridge *br = netdev_priv(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);

	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 */
	br->fake_rtable.dst.metrics[RTAX_MTU - 1] = 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;
	}

	#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 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,
	};

	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
	};

	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;
	}