linux-toradex.git/drivers/net/bonding/bond_sysfs.c, branch v3.11

bonding: add an option to fail when any of arp_ip_target is inaccessible

2013-06-25T23:58:38+00:00

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
arp_ip_targets.

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
   slave.

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
   bond->params.arp_targets[].

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

Also, update the documentation to reflect the new parameter.

v3->v4:
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.

v2->v3:
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.

v1->v2:
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: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: add helper function bond_get_targets_ip(targets, ip)

2013-06-25T23:58:37+00:00

Add function bond_get_targets_ip(targets, ip) which searches through
targets array of ips (arp_targets) and returns the position of first
match. If ip == 0, returns the first free slot. On failure to find the
ip or free slot, return -1.

Use it to verify if the arp we've received is valid and in sysfs.

v1->v2:
Fix "[2/6] bonding: add helper function bond_get_targets_ip(targets, ip)",
per Nikolay's advice, to verify if source ip != 0.0.0.0, otherwise we might
update 'null' arp_ip_targets' last_rx. Also, address style.

Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: trivial: update the comments to reflect the reality

2013-05-29T06:57:23+00:00

Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: allow xmit hash policy change while bond dev is up

2013-05-28T06:27:14+00:00

Since the xmit_hash_policy pointer is always valid and not dependent on
anything, we can change it while the bond device is up and running. The
only downside would be the out of order packets but that is a small price
to pay.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bonding: fix multiple 3ad mode sysfs race conditions

2013-05-20T06:25:49+00:00

When bond_3ad_get_active_agg_info() is used in all show_ad_ functions
it is not protected against slave manipulation and since it walks over
the slaves and uses them, this can easily result in NULL pointer
dereference or use of freed memory. Both the new wrapper and the
internal function are exported to the bonding as they're needed in
different places.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bonding: fix set mode race conditions

2013-05-20T06:25:49+00:00

Changing the mode without any locking can result in multiple races (e.g.
upping a bond, enslaving/releasing). Depending on which race is hit the
impact can vary from incosistent bond state to kernel crash.
Use RTNL to synchronize the mode setting with the dangerous races.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bonding: fix disabling of arp_interval and miimon

2013-03-29T19:02:49+00:00

Currently if either arp_interval or miimon is disabled, they both get
disabled, and upon disabling they get executed once more which is not
the proper behaviour. Also when doing a no-op and disabling an already
disabled one, the other again gets disabled.
Also fix the error messages with the proper valid ranges, and a small
typo fix in the up delay error message (outputting "down delay", instead
of "up delay").

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bonding: remove already created master sysfs link on failure

2013-03-26T17:00:02+00:00

If slave sysfs symlink failes to be created - we end up without removing
the master sysfs symlink. Remove it in case of failure.

Signed-off-by: Veaceslav Falico 
Signed-off-by: David S. Miller

bonding: unset primary slave via sysfs

2013-01-29T20:43:35+00:00

When bonding module is loaded with primary parameter and one decides to unset
primary slave using sysfs these settings are not preserved during bond device
restart. Primary slave is only unset once and it's not remembered in
bond->params structure. Below is example of recreation.

 grep OPTS /etc/sysconfig/network-scripts/ifcfg-bond0
BONDING_OPTS="mode=active-backup miimon=100 primary=eth01"
 grep "Primary Slave" /proc/net/bonding/bond0
Primary Slave: eth01 (primary_reselect always)

 echo "" > /sys/class/net/bond0/bonding/primary
 grep "Primary Slave" /proc/net/bonding/bond0
Primary Slave: None

 sed -i -e 's/primary=eth01//' /etc/sysconfig/network-scripts/ifcfg-bond0
 grep OPTS /etc/sysconfig/network-scripts/ifcfg-bond
BONDING_OPTS="mode=active-backup miimon=100 "
 ifdown bond0 && ifup bond0

without patch:
 grep "Primary Slave" /proc/net/bonding/bond0
Primary Slave: eth01 (primary_reselect always)

with patch:
 grep "Primary Slave" /proc/net/bonding/bond0
Primary Slave: None

Reviewed-by: Jiri Pirko 
Signed-off-by: Milos Vyletel 
Signed-off-by: Jay Vosburgh 
Signed-off-by: David S. Miller

bonding: fix race condition in bonding_store_slaves_active

2012-11-29T18:13:15+00:00

Race between bonding_store_slaves_active() and slave manipulation
 functions. The bond_for_each_slave use in bonding_store_slaves_active()
 is not protected by any synchronization mechanism.
 NULL pointer dereference is easy to reach.
 Fixed by acquiring the bond->lock for the slave walk.

 v2: Make description text < 75 columns

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: Jay Vosburgh 
Signed-off-by: David S. Miller