bonding: gratuitous ARP

Add support for generating gratuitous ARPs in bonding
active-backup mode when failovers occur.  Includes support for VLAN
tagging the ARPs as needed.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
This commit is contained in:
Jay Vosburgh 2005-06-26 17:52:20 -04:00 committed by Jeff Garzik
parent 12755c16a9
commit c3ade5cad0
2 changed files with 255 additions and 34 deletions

View File

@ -475,7 +475,10 @@
* Solution is to move call to dev_remove_pack outside of the
* spinlock.
* Set version to 2.6.1.
*
* 2005/06/05 - Jay Vosburgh <fubar@us.ibm.com>
* - Support for generating gratuitous ARPs in active-backup mode.
* Includes support for VLAN tagging all bonding-generated ARPs
* as needed. Set version to 2.6.2.
*/
//#define BONDING_DEBUG 1
@ -519,6 +522,7 @@
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/if_bonding.h>
#include <net/route.h>
#include "bonding.h"
#include "bond_3ad.h"
#include "bond_alb.h"
@ -574,7 +578,6 @@ static struct proc_dir_entry *bond_proc_dir = NULL;
static u32 arp_target[BOND_MAX_ARP_TARGETS] = { 0, } ;
static int arp_ip_count = 0;
static u32 my_ip = 0;
static int bond_mode = BOND_MODE_ROUNDROBIN;
static int lacp_fast = 0;
static int app_abi_ver = 0;
@ -611,6 +614,7 @@ static struct bond_parm_tbl bond_mode_tbl[] = {
/*-------------------------- Forward declarations ---------------------------*/
static inline void bond_set_mode_ops(struct net_device *bond_dev, int mode);
static void bond_send_gratuitous_arp(struct bonding *bond);
/*---------------------------- General routines -----------------------------*/
@ -659,6 +663,7 @@ static int bond_add_vlan(struct bonding *bond, unsigned short vlan_id)
INIT_LIST_HEAD(&vlan->vlan_list);
vlan->vlan_id = vlan_id;
vlan->vlan_ip = 0;
write_lock_bh(&bond->lock);
@ -1468,16 +1473,6 @@ static void bond_change_active_slave(struct bonding *bond, struct slave *new_act
}
}
if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
if (old_active) {
bond_set_slave_inactive_flags(old_active);
}
if (new_active) {
bond_set_slave_active_flags(new_active);
}
}
if (USES_PRIMARY(bond->params.mode)) {
bond_mc_swap(bond, new_active, old_active);
}
@ -1488,6 +1483,17 @@ static void bond_change_active_slave(struct bonding *bond, struct slave *new_act
} else {
bond->curr_active_slave = new_active;
}
if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
if (old_active) {
bond_set_slave_inactive_flags(old_active);
}
if (new_active) {
bond_set_slave_active_flags(new_active);
}
bond_send_gratuitous_arp(bond);
}
}
/**
@ -2694,15 +2700,180 @@ out:
read_unlock(&bond->lock);
}
static u32 bond_glean_dev_ip(struct net_device *dev)
{
struct in_device *idev;
struct in_ifaddr *ifa;
u32 addr = 0;
if (!dev)
return 0;
rcu_read_lock();
idev = __in_dev_get(dev);
if (!idev)
goto out;
ifa = idev->ifa_list;
if (!ifa)
goto out;
addr = ifa->ifa_local;
out:
rcu_read_unlock();
return addr;
}
static int bond_has_ip(struct bonding *bond)
{
struct vlan_entry *vlan, *vlan_next;
if (bond->master_ip)
return 1;
if (list_empty(&bond->vlan_list))
return 0;
list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
vlan_list) {
if (vlan->vlan_ip)
return 1;
}
return 0;
}
/*
* We go to the (large) trouble of VLAN tagging ARP frames because
* switches in VLAN mode (especially if ports are configured as
* "native" to a VLAN) might not pass non-tagged frames.
*/
static void bond_arp_send(struct net_device *slave_dev, int arp_op, u32 dest_ip, u32 src_ip, unsigned short vlan_id)
{
struct sk_buff *skb;
dprintk("arp %d on slave %s: dst %x src %x vid %d\n", arp_op,
slave_dev->name, dest_ip, src_ip, vlan_id);
skb = arp_create(arp_op, ETH_P_ARP, dest_ip, slave_dev, src_ip,
NULL, slave_dev->dev_addr, NULL);
if (!skb) {
printk(KERN_ERR DRV_NAME ": ARP packet allocation failed\n");
return;
}
if (vlan_id) {
skb = vlan_put_tag(skb, vlan_id);
if (!skb) {
printk(KERN_ERR DRV_NAME ": failed to insert VLAN tag\n");
return;
}
}
arp_xmit(skb);
}
static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
{
int i;
int i, vlan_id, rv;
u32 *targets = bond->params.arp_targets;
struct vlan_entry *vlan, *vlan_next;
struct net_device *vlan_dev;
struct flowi fl;
struct rtable *rt;
for (i = 0; (i < BOND_MAX_ARP_TARGETS) && targets[i]; i++) {
arp_send(ARPOP_REQUEST, ETH_P_ARP, targets[i], slave->dev,
my_ip, NULL, slave->dev->dev_addr,
NULL);
dprintk("basa: target %x\n", targets[i]);
if (list_empty(&bond->vlan_list)) {
dprintk("basa: empty vlan: arp_send\n");
bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
bond->master_ip, 0);
continue;
}
/*
* If VLANs are configured, we do a route lookup to
* determine which VLAN interface would be used, so we
* can tag the ARP with the proper VLAN tag.
*/
memset(&fl, 0, sizeof(fl));
fl.fl4_dst = targets[i];
fl.fl4_tos = RTO_ONLINK;
rv = ip_route_output_key(&rt, &fl);
if (rv) {
if (net_ratelimit()) {
printk(KERN_WARNING DRV_NAME
": %s: no route to arp_ip_target %u.%u.%u.%u\n",
bond->dev->name, NIPQUAD(fl.fl4_dst));
}
continue;
}
/*
* This target is not on a VLAN
*/
if (rt->u.dst.dev == bond->dev) {
dprintk("basa: rtdev == bond->dev: arp_send\n");
bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
bond->master_ip, 0);
continue;
}
vlan_id = 0;
list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
vlan_list) {
vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
if (vlan_dev == rt->u.dst.dev) {
vlan_id = vlan->vlan_id;
dprintk("basa: vlan match on %s %d\n",
vlan_dev->name, vlan_id);
break;
}
}
if (vlan_id) {
bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
vlan->vlan_ip, vlan_id);
continue;
}
if (net_ratelimit()) {
printk(KERN_WARNING DRV_NAME
": %s: no path to arp_ip_target %u.%u.%u.%u via rt.dev %s\n",
bond->dev->name, NIPQUAD(fl.fl4_dst),
rt->u.dst.dev ? rt->u.dst.dev->name : "NULL");
}
}
}
/*
* Kick out a gratuitous ARP for an IP on the bonding master plus one
* for each VLAN above us.
*/
static void bond_send_gratuitous_arp(struct bonding *bond)
{
struct slave *slave = bond->curr_active_slave;
struct vlan_entry *vlan;
struct net_device *vlan_dev;
dprintk("bond_send_grat_arp: bond %s slave %s\n", bond->dev->name,
slave ? slave->dev->name : "NULL");
if (!slave)
return;
if (bond->master_ip) {
bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
bond->master_ip, 0);
}
list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
if (vlan->vlan_ip) {
bond_arp_send(slave->dev, ARPOP_REPLY, vlan->vlan_ip,
vlan->vlan_ip, vlan->vlan_id);
}
}
}
@ -2781,7 +2952,7 @@ static void bond_loadbalance_arp_mon(struct net_device *bond_dev)
*/
if (((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
(((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
my_ip)) {
bond_has_ip(bond))) {
slave->link = BOND_LINK_DOWN;
slave->state = BOND_STATE_BACKUP;
@ -2920,7 +3091,7 @@ static void bond_activebackup_arp_mon(struct net_device *bond_dev)
if ((slave != bond->curr_active_slave) &&
(!bond->current_arp_slave) &&
(((jiffies - slave->dev->last_rx) >= 3*delta_in_ticks) &&
my_ip)) {
bond_has_ip(bond))) {
/* a backup slave has gone down; three times
* the delta allows the current slave to be
* taken out before the backup slave.
@ -2966,8 +3137,8 @@ static void bond_activebackup_arp_mon(struct net_device *bond_dev)
* if it is up and needs to take over as the curr_active_slave
*/
if ((((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
(((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
my_ip)) &&
(((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
bond_has_ip(bond))) &&
((jiffies - slave->jiffies) >= 2*delta_in_ticks)) {
slave->link = BOND_LINK_DOWN;
@ -3019,7 +3190,7 @@ static void bond_activebackup_arp_mon(struct net_device *bond_dev)
/* the current slave must tx an arp to ensure backup slaves
* rx traffic
*/
if (slave && my_ip) {
if (slave && bond_has_ip(bond)) {
bond_arp_send_all(bond, slave);
}
}
@ -3471,10 +3642,67 @@ static int bond_netdev_event(struct notifier_block *this, unsigned long event, v
return NOTIFY_DONE;
}
/*
* bond_inetaddr_event: handle inetaddr notifier chain events.
*
* We keep track of device IPs primarily to use as source addresses in
* ARP monitor probes (rather than spewing out broadcasts all the time).
*
* We track one IP for the main device (if it has one), plus one per VLAN.
*/
static int bond_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
{
struct in_ifaddr *ifa = ptr;
struct net_device *vlan_dev, *event_dev = ifa->ifa_dev->dev;
struct bonding *bond, *bond_next;
struct vlan_entry *vlan, *vlan_next;
list_for_each_entry_safe(bond, bond_next, &bond_dev_list, bond_list) {
if (bond->dev == event_dev) {
switch (event) {
case NETDEV_UP:
bond->master_ip = ifa->ifa_local;
return NOTIFY_OK;
case NETDEV_DOWN:
bond->master_ip = bond_glean_dev_ip(bond->dev);
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
}
if (list_empty(&bond->vlan_list))
continue;
list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
vlan_list) {
vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
if (vlan_dev == event_dev) {
switch (event) {
case NETDEV_UP:
vlan->vlan_ip = ifa->ifa_local;
return NOTIFY_OK;
case NETDEV_DOWN:
vlan->vlan_ip =
bond_glean_dev_ip(vlan_dev);
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
}
}
}
return NOTIFY_DONE;
}
static struct notifier_block bond_netdev_notifier = {
.notifier_call = bond_netdev_event,
};
static struct notifier_block bond_inetaddr_notifier = {
.notifier_call = bond_inetaddr_event,
};
/*-------------------------- Packet type handling ---------------------------*/
/* register to receive lacpdus on a bond */
@ -4060,17 +4288,6 @@ static int bond_xmit_activebackup(struct sk_buff *skb, struct net_device *bond_d
struct bonding *bond = bond_dev->priv;
int res = 1;
/* if we are sending arp packets, try to at least
identify our own ip address */
if (bond->params.arp_interval && !my_ip &&
(skb->protocol == __constant_htons(ETH_P_ARP))) {
char *the_ip = (char *)skb->data +
sizeof(struct ethhdr) +
sizeof(struct arphdr) +
ETH_ALEN;
memcpy(&my_ip, the_ip, 4);
}
read_lock(&bond->lock);
read_lock(&bond->curr_slave_lock);
@ -4669,6 +4886,7 @@ static int __init bonding_init(void)
rtnl_unlock();
register_netdevice_notifier(&bond_netdev_notifier);
register_inetaddr_notifier(&bond_inetaddr_notifier);
return 0;
@ -4684,6 +4902,7 @@ out_err:
static void __exit bonding_exit(void)
{
unregister_netdevice_notifier(&bond_netdev_notifier);
unregister_inetaddr_notifier(&bond_inetaddr_notifier);
rtnl_lock();
bond_free_all();

View File

@ -36,8 +36,8 @@
#include "bond_3ad.h"
#include "bond_alb.h"
#define DRV_VERSION "2.6.1"
#define DRV_RELDATE "October 29, 2004"
#define DRV_VERSION "2.6.2"
#define DRV_RELDATE "June 5, 2005"
#define DRV_NAME "bonding"
#define DRV_DESCRIPTION "Ethernet Channel Bonding Driver"
@ -149,6 +149,7 @@ struct bond_params {
struct vlan_entry {
struct list_head vlan_list;
u32 vlan_ip;
unsigned short vlan_id;
};
@ -197,6 +198,7 @@ struct bonding {
#endif /* CONFIG_PROC_FS */
struct list_head bond_list;
struct dev_mc_list *mc_list;
u32 master_ip;
u16 flags;
struct ad_bond_info ad_info;
struct alb_bond_info alb_info;