#!/bin/sh
# Only supported driver for now is r8169 ,ake it configurable in the future
driver='r8169'
sys_drv_name="$driver"'-vfnetdev'
intf='enp4s0'
 
usage() {
	echo "$0 create/destroy <interface name(optional)>. Default $intf"
	exit 1
}

[ $# -lt 1 ] && usage
[ -n "$2" ] && intf="$2"

echo "Checking for interface $intf"
if [ ! -e "/sys/class/net/$intf/device/mdev_supported_types/$sys_drv_name/create" ]; then
	echo "interface $intf has no vfio-mdev support"
	exit 1
fi

vf_create() {
	dev_uuid=$(uuidgen)
	sudo sh -c "echo $dev_uuid > /sys/class/net/$intf/device/mdev_supported_types/$sys_drv_name/create"
	#sudo sh -c "echo $dev_uuid > /sys/class/net/$intf/mdev_supported_types/net-vfnetdev/create"
	#the newly created mdev is not tied to any port of the parent deice yet
	echo "Bind $intf to the newly created mdevice $dev_uuid"
	sudo sh -c "echo $intf > /sys/bus/mdev/devices/$dev_uuid/vfnetdev/netdev"
	#ensure the IOMMU group is readble by non root program
	vfio_group=$(basename $(readlink /sys/bus/mdev/devices/$dev_uuid/iommu_group))
	user=$(whoami)
	grp=$(id -g -n $user)
	sudo chown "$user":"$grp" /dev/vfio/$vfio_group
	echo "created $dev_uuid"
	echo "Run ./r8169 $vfio_group $dev_uuid"
}

vf_destroy() {
	# FIXME only one mdev per ethernet supported for now
	echo 1 > /sys/class/mdev_bus/$intf/*/remove > /dev/null
}

case "$1" in
	create)
		vf_create
		;;
	destroy)
		vf_destroy
		;;
	*)
		usage
		;;
esac