#!/bin/sh

# Copyright (C) 2008,2009 Citrix Systems, Inc. All rights reserved.
# Copyright (C) 2009 Nicira Networks, Inc.

# CA-23900: Warning: when VIFs are added to windows guests with PV drivers the backend vif device is registered,
# unregistered and then registered again. This causes the udev event to fire twice and this script runs twice.
# Since the first invocation of the script races with the device unregistration, spurious errors are possible
# which will be logged but are safe to ignore since the second script invocation should complete the operation.
# Note that each script invocation is run synchronously from udev and so the scripts don't race with each other.

# Keep other-config/ keys in sync with device.ml:vif_udev_keys

cfg_mod="/usr/bin/ovs-cfg-mod"
dump_vif_details="/usr/share/vswitch/scripts/dump-vif-details"
service="/sbin/service"

TYPE=`echo ${XENBUS_PATH} | cut -f 2 -d '/'`
DOMID=`echo ${XENBUS_PATH} | cut -f 3 -d '/'`
DEVID=`echo ${XENBUS_PATH} | cut -f 4 -d '/'`

XAPI=/xapi/${DOMID}/hotplug/${TYPE}/${DEVID}
HOTPLUG=/xapi/${DOMID}/hotplug/${TYPE}/${DEVID}
PRIVATE=/xapi/${DOMID}/private/${TYPE}/${DEVID}
BRCTL=/usr/sbin/brctl
IP=/sbin/ip


handle_promiscuous()
{
    local arg=$(xenstore-read "${PRIVATE}/other-config/promiscuous")
    if [ $? -eq 0 -a -n "${arg}" ] ; then
        case "${arg}" in 
            true|on) logger -t script-vif "${vif}: Promiscuous ports are not supported via vSwitch." ;;
            *) ;;
        esac
    fi
}

handle_ethtool()
{
    local opt=$1
    local arg=$(xenstore-read "${PRIVATE}/other-config/ethtool-${opt}")
    if [ $? -eq 0 -a -n "${arg}" ] ; then
        case "${arg}" in
            true|on)   /sbin/ethtool -K "${vif}" "${opt}" on ;;
            false|off) /sbin/ethtool -K "${vif}" "${opt}" off ;;
            *) logger -t scripts-vif "Unknown ethtool argument ${opt}=${arg} on ${vif}/${VIFUUID}" ;;
        esac
    fi
}

handle_mtu()
{
    local mtu=$(xenstore-read "${PRIVATE}/MTU")
    if [ $? -eq 0 -a -n "${mtu}" ]; then
	echo "${mtu}" > /sys/class/net/${vif}/mtu
    fi
}

add_to_bridge()
{
    local address=$(xenstore-read "${PRIVATE}/bridge-MAC")
    if [ $? -ne 0 -o -z "${address}" ]; then
	logger -t scripts-vif "Failed to read ${PRIVATE}/bridge-MAC from xenstore"
    fi
    local bridge=$(xenstore-read "${PRIVATE}/bridge")
    if [ $? -ne 0 -o -z "${bridge}" ]; then
	logger -t scripts-vif "Failed to read ${PRIVATE}/bridge from xenstore"
    fi
    logger -t scripts-vif "Adding ${vif} to ${bridge} with address ${address}"

    vid=
    if [ -e "/var/lib/openvswitch/br-$bridge" ]; then
	. "/var/lib/openvswitch/br-$bridge"
	if [ -n "$VLAN_SLAVE" -a -n "$VLAN_VID" ]; then
	    bridge=$VLAN_SLAVE
	    vid="--add=vlan.$vif.tag=$VLAN_VID"
	fi
    fi

    ${IP} link set "${vif}" down                        || logger -t scripts-vif "Failed to ip link set ${vif} down"
    ${IP} link set "${vif}" arp off                     || logger -t scripts-vif "Failed to ip link set ${vif} arp off"
    ${IP} link set "${vif}" multicast off               || logger -t scripts-vif "Failed to ip link set ${vif} multicast off"
    ${IP} link set "${vif}" address "${address}"        || logger -t scripts-vif "Failed to ip link set ${vif} address ${address}"
    ${IP} addr flush "${vif}"                           || logger -t scripts-vif "Failed to ip addr flush ${vif}"

    local vif_details=$($dump_vif_details $DOMID $DEVID)
    if [ $? -ne 0 -o -z "${vif_details}" ]; then
	    logger -t scripts-vif "Failed to retrieve vif details for vswitch"
    fi

    $cfg_mod -F /etc/ovs-vswitchd.conf \
        --del-match="bridge.*.port=$vif" \
        --del-match="vlan.$vif.[!0-9]*" \
        --del-match="port.$vif.[!0-9]*" \
        --add="bridge.$bridge.port=$vif" \
        $vid $vif_details -c 
    $service vswitch reload

    ${IP} link set "${vif}" up                          || logger -t scripts-vif "Failed to ip link set ${vif} up"
}

echo Called as "$@" "$TYPE" "$DOMID" "$DEVID" | logger -t scripts-vif
case "$1" in
online)
	handle_ethtool rx
	handle_ethtool tx
	handle_ethtool sg
	handle_ethtool tso
	handle_ethtool ufo
	handle_ethtool gso

	handle_mtu
	add_to_bridge
	handle_promiscuous

	xenstore-write "${HOTPLUG}/vif" "${vif}"
	xenstore-write "${HOTPLUG}/hotplug" "online"

	# xs-xen.pq.hq:91e986b8e49f netback-wait-for-hotplug
	xenstore-write "/local/domain/0/backend/vif/${DOMID}/${DEVID}/hotplug-status" "connected"

	;;
remove)
	xenstore-rm "${HOTPLUG}/hotplug"
	vif=vif${DOMID}.${DEVID}
	logger -t scripts-vif "${vif} has been removed"
	$cfg_mod -vANY:console:emer -F /etc/ovs-vswitchd.conf \
	    --del-match="bridge.*.port=${vif}" \
	    --del-match="vlan.${vif}.[!0-9]*" \
	    --del-match="port.${vif}.[!0-9]*" -c
	$service vswitch reload
	;;
esac