Commit 8599b52e authored by Veaceslav Falico's avatar Veaceslav Falico Committed by David S. Miller
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bonding: add an option to fail when any of arp_ip_target is inaccessible

Currently, we fail only when all of the ips in arp_ip_target are gone.
However, in some situations we might need to fail if even one host from
arp_ip_target becomes unavailable.

All situations, obviously, rely on the idea that we need *completely*
functional network, with all interfaces/addresses working correctly.

One real world example might be:
vlans on top on bond (hybrid port). If bond and vlans have ips assigned
and we have their peers monitored via arp_ip_target - in case of switch
misconfiguration (trunk/access port), slave driver malfunction or
tagged/untagged traffic dropped on the way - we will be able to switch
to another slave.

Though any other configuration needs that if we need to have access to all

This patch adds this possibility by adding a new parameter -
arp_all_targets (both as a module parameter and as a sysfs knob). It can be
set to:

	0 or any (the default) - which works exactly as it's working now -
	the slave is up if any of the arp_ip_targets are up.

	1 or all - the slave is up if all of the arp_ip_targets are up.

This parameter can be changed on the fly (via sysfs), and requires the mode
to be active-backup and arp_validate to be enabled (it obeys the
arp_validate config on which slaves to validate).

Internally it's done through:

1) Add target_last_arp_rx[BOND_MAX_ARP_TARGETS] array to slave struct. It's
   an array of jiffies, meaning that slave->target_last_arp_rx[i] is the
   last time we've received arp from bond->params.arp_targets[i] on this

2) If we successfully validate an arp from bond->params.arp_targets[i] in
   bond_validate_arp() - update the slave->target_last_arp_rx[i] with the
   current jiffies value.

3) When getting slave's last_rx via slave_last_rx(), we return the oldest
   time when we've received an arp from any address in

If the value of arp_all_targets == 0 - we still work the same way as

Also, update the documentation to reflect the new parameter.

Kill the forgotten rtnl_unlock(), rephrase the documentation part to be
more clear, don't fail setting arp_all_targets if arp_validate is not set -
it has no effect anyway but can be easier to set up. Also, print a warning
if the last arp_ip_target is removed while the arp_interval is on, but not
the arp_validate.

Use _bh spinlock, remove useless rtnl_lock() and use jiffies for new
arp_ip_target last arp, instead of slave_last_rx(). On bond_enslave(),
use the same initialization value for target_last_arp_rx[] as is used
for the default last_arp_rx, to avoid useless interface flaps.

Also, instead of failing to remove the last arp_ip_target just print a
warning - otherwise it might break existing scripts.

Correctly handle adding/removing hosts in arp_ip_target - we need to
shift/initialize all slave's target_last_arp_rx. Also, don't fail module
loading on arp_all_targets misconfiguration, just disable it, and some
minor style fixes.
Signed-off-by: default avatarVeaceslav Falico <>
Signed-off-by: default avatarDavid S. Miller <>
parent d7d35c68
......@@ -321,6 +321,25 @@ arp_validate
This option was added in bonding version 3.1.0.
Specifies the quantity of arp_ip_targets that must be reachable
in order for the ARP monitor to consider a slave as being up.
This option affects only active-backup mode for slaves with
arp_validation enabled.
Possible values are:
any or 0
consider the slave up only when any of the arp_ip_targets
is reachable
all or 1
consider the slave up only when all of the arp_ip_targets
are reachable
Specifies the time, in milliseconds, to wait before disabling
......@@ -104,6 +104,7 @@ static char *xmit_hash_policy;
static int arp_interval = BOND_LINK_ARP_INTERV;
static char *arp_ip_target[BOND_MAX_ARP_TARGETS];
static char *arp_validate;
static char *arp_all_targets;
static char *fail_over_mac;
static int all_slaves_active = 0;
static struct bond_params bonding_defaults;
......@@ -166,6 +167,8 @@ module_param(arp_validate, charp, 0);
MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes; "
"0 for none (default), 1 for active, "
"2 for backup, 3 for all");
module_param(arp_all_targets, charp, 0);
MODULE_PARM_DESC(arp_all_targets, "fail on any/all arp targets timeout; 0 for any (default), 1 for all");
module_param(fail_over_mac, charp, 0);
MODULE_PARM_DESC(fail_over_mac, "For active-backup, do not set all slaves to "
"the same MAC; 0 for none (default), "
......@@ -216,6 +219,12 @@ const struct bond_parm_tbl xmit_hashtype_tbl[] = {
{ NULL, -1},
const struct bond_parm_tbl arp_all_targets_tbl[] = {
{ NULL, -1},
const struct bond_parm_tbl arp_validate_tbl[] = {
......@@ -1483,7 +1492,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
struct slave *new_slave = NULL;
struct sockaddr addr;
int link_reporting;
int res = 0;
int res = 0, i;
if (!bond->params.use_carrier &&
slave_dev->ethtool_ops->get_link == NULL &&
......@@ -1712,6 +1721,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
new_slave->last_arp_rx = jiffies -
(msecs_to_jiffies(bond->params.arp_interval) + 1);
for (i = 0; i < BOND_MAX_ARP_TARGETS; i++)
new_slave->target_last_arp_rx[i] = new_slave->last_arp_rx;
if (bond->params.miimon && !bond->params.use_carrier) {
link_reporting = bond_check_dev_link(bond, slave_dev, 1);
......@@ -2610,16 +2621,20 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
static void bond_validate_arp(struct bonding *bond, struct slave *slave, __be32 sip, __be32 tip)
int i;
if (!sip || !bond_has_this_ip(bond, tip)) {
pr_debug("bva: sip %pI4 tip %pI4 not found\n", &sip, &tip);
if (bond_get_targets_ip(bond->params.arp_targets, sip) == -1) {
i = bond_get_targets_ip(bond->params.arp_targets, sip);
if (i == -1) {
pr_debug("bva: sip %pI4 not found in targets\n", &sip);
slave->last_arp_rx = jiffies;
slave->target_last_arp_rx[i] = jiffies;
static int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
......@@ -4409,6 +4424,7 @@ int bond_parse_parm(const char *buf, const struct bond_parm_tbl *tbl)
static int bond_check_params(struct bond_params *params)
int arp_validate_value, fail_over_mac_value, primary_reselect_value, i;
int arp_all_targets_value;
* Convert string parameters.
......@@ -4634,6 +4650,18 @@ static int bond_check_params(struct bond_params *params)
} else
arp_validate_value = 0;
arp_all_targets_value = 0;
if (arp_all_targets) {
arp_all_targets_value = bond_parse_parm(arp_all_targets,
if (arp_all_targets_value == -1) {
pr_err("Error: invalid arp_all_targets_value \"%s\"\n",
arp_all_targets_value = 0;
if (miimon) {
pr_info("MII link monitoring set to %d ms\n", miimon);
} else if (arp_interval) {
......@@ -4698,6 +4726,7 @@ static int bond_check_params(struct bond_params *params)
params->num_peer_notif = num_peer_notif;
params->arp_interval = arp_interval;
params->arp_validate = arp_validate_value;
params->arp_all_targets = arp_all_targets_value;
params->updelay = updelay;
params->downdelay = downdelay;
params->use_carrier = use_carrier;
......@@ -443,6 +443,44 @@ static ssize_t bonding_store_arp_validate(struct device *d,
static DEVICE_ATTR(arp_validate, S_IRUGO | S_IWUSR, bonding_show_arp_validate,
* Show and set arp_all_targets.
static ssize_t bonding_show_arp_all_targets(struct device *d,
struct device_attribute *attr,
char *buf)
struct bonding *bond = to_bond(d);
int value = bond->params.arp_all_targets;
return sprintf(buf, "%s %d\n", arp_all_targets_tbl[value].modename,
static ssize_t bonding_store_arp_all_targets(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
struct bonding *bond = to_bond(d);
int new_value;
new_value = bond_parse_parm(buf, arp_all_targets_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid arp_all_targets value %s\n",
bond->dev->name, buf);
return -EINVAL;
pr_info("%s: setting arp_all_targets to %s (%d).\n",
bond->dev->name, arp_all_targets_tbl[new_value].modename,
bond->params.arp_all_targets = new_value;
return count;
static DEVICE_ATTR(arp_all_targets, S_IRUGO | S_IWUSR,
bonding_show_arp_all_targets, bonding_store_arp_all_targets);
* Show and store fail_over_mac. User only allowed to change the
......@@ -590,10 +628,11 @@ static ssize_t bonding_store_arp_targets(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
__be32 newtarget;
int i = 0, ret = -EINVAL;
struct bonding *bond = to_bond(d);
__be32 *targets;
struct slave *slave;
__be32 newtarget, *targets;
unsigned long *targets_rx;
int ind, i, j, ret = -EINVAL;
targets = bond->params.arp_targets;
newtarget = in_aton(buf + 1);
......@@ -611,8 +650,8 @@ static ssize_t bonding_store_arp_targets(struct device *d,
goto out;
i = bond_get_targets_ip(targets, 0); /* first free slot */
if (i == -1) {
ind = bond_get_targets_ip(targets, 0); /* first free slot */
if (ind == -1) {
pr_err("%s: ARP target table is full!\n",
goto out;
......@@ -620,7 +659,12 @@ static ssize_t bonding_store_arp_targets(struct device *d,
pr_info("%s: adding ARP target %pI4.\n", bond->dev->name,
targets[i] = newtarget;
/* not to race with bond_arp_rcv */
bond_for_each_slave(bond, slave, i)
slave->target_last_arp_rx[ind] = jiffies;
targets[ind] = newtarget;
} else if (buf[0] == '-') {
if ((newtarget == 0) || (newtarget == htonl(INADDR_BROADCAST))) {
pr_err("%s: invalid ARP target %pI4 specified for removal\n",
......@@ -628,18 +672,32 @@ static ssize_t bonding_store_arp_targets(struct device *d,
goto out;
i = bond_get_targets_ip(targets, newtarget);
if (i == -1) {
pr_info("%s: unable to remove nonexistent ARP target %pI4.\n",
ind = bond_get_targets_ip(targets, newtarget);
if (ind == -1) {
pr_err("%s: unable to remove nonexistent ARP target %pI4.\n",
bond->dev->name, &newtarget);
goto out;
if (ind == 0 && !targets[1] && bond->params.arp_interval)
pr_warn("%s: removing last arp target with arp_interval on\n",
pr_info("%s: removing ARP target %pI4.\n", bond->dev->name,
for (; (i < BOND_MAX_ARP_TARGETS-1) && targets[i+1]; i++)
bond_for_each_slave(bond, slave, i) {
targets_rx = slave->target_last_arp_rx;
j = ind;
for (; (j < BOND_MAX_ARP_TARGETS-1) && targets[j+1]; j++)
targets_rx[j] = targets_rx[j+1];
targets_rx[j] = 0;
for (i = ind; (i < BOND_MAX_ARP_TARGETS-1) && targets[i+1]; i++)
targets[i] = targets[i+1];
targets[i] = 0;
} else {
pr_err("no command found in arp_ip_targets file for bond %s. Use +<addr> or -<addr>.\n",
......@@ -1623,6 +1681,7 @@ static struct attribute *per_bond_attrs[] = {
......@@ -144,6 +144,7 @@ struct bond_params {
u8 num_peer_notif;
int arp_interval;
int arp_validate;
int arp_all_targets;
int use_carrier;
int fail_over_mac;
int updelay;
......@@ -179,6 +180,7 @@ struct slave {
int delay;
unsigned long jiffies;
unsigned long last_arp_rx;
unsigned long target_last_arp_rx[BOND_MAX_ARP_TARGETS];
s8 link; /* one of BOND_LINK_XXXX */
s8 new_link;
u8 backup:1, /* indicates backup slave. Value corresponds with
......@@ -322,6 +324,9 @@ static inline bool bond_is_active_slave(struct slave *slave)
......@@ -334,11 +339,31 @@ static inline int slave_do_arp_validate(struct bonding *bond,
return bond->params.arp_validate & (1 << bond_slave_state(slave));
/* Get the oldest arp which we've received on this slave for bond's
* arp_targets.
static inline unsigned long slave_oldest_target_arp_rx(struct bonding *bond,
struct slave *slave)
int i = 1;
unsigned long ret = slave->target_last_arp_rx[0];
for (; (i < BOND_MAX_ARP_TARGETS) && bond->params.arp_targets[i]; i++)
if (time_before(slave->target_last_arp_rx[i], ret))
ret = slave->target_last_arp_rx[i];
return ret;
static inline unsigned long slave_last_rx(struct bonding *bond,
struct slave *slave)
if (slave_do_arp_validate(bond, slave))
return slave->last_arp_rx;
if (slave_do_arp_validate(bond, slave)) {
if (bond->params.arp_all_targets == BOND_ARP_TARGETS_ALL)
return slave_oldest_target_arp_rx(bond, slave);
return slave->last_arp_rx;
return slave->dev->last_rx;
......@@ -486,6 +511,7 @@ extern const struct bond_parm_tbl bond_lacp_tbl[];
extern const struct bond_parm_tbl bond_mode_tbl[];
extern const struct bond_parm_tbl xmit_hashtype_tbl[];
extern const struct bond_parm_tbl arp_validate_tbl[];
extern const struct bond_parm_tbl arp_all_targets_tbl[];
extern const struct bond_parm_tbl fail_over_mac_tbl[];
extern const struct bond_parm_tbl pri_reselect_tbl[];
extern struct bond_parm_tbl ad_select_tbl[];
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