Guest-to-host

The following describes a configuration for a virtio-net vdev for a node in a guest communicating with a devnp-vdevpeer.so driver in the hypervisor host.

The figure below illustrates a peer-to-peer connection using a virtio-net vdev in a guest and the devnp-vdevpeer.so io-pkt-* driver running in the hypervisor host (see devnp-vdevpeer.so in the “Utilities and Drivers Reference” chapter).

Figure 1. Guest-to-host communication using the virtio-net vdev to a peer node provided by the devnp-vdevpeer.so io-pkt-* driver.

The following shows the virtio-net vdev configuration in the *.qvmconf file for the VM (qvm process instance) hosting the guest, along with the vdevpeer driver startup options that will enable the hypervisor host to connect to a node in the guest, and the instructions to enable the interface.

Configure a virtio-net vdev

For an QNX Neutrino 7.0 guest on an ARM board, configure a virtio-net vdev in the VM as follows:

system qnx7-arm-guest
...
# The loc and intr gic options are for ARM only. The guest
# will see the virtio-net vdev as a memory-mapped I/O device
# at the specified location.

vdev virtio-net
	loc 0x1c0c0000
	intr gic:40
	mac aa:aa:aa:aa:aa:aa
	name p2p
	peer /dev/vdevpeers/vp0

where:

qnx7-arm-guest: The guest system name, also specified by the vdevpeer peer option: peer=/dev/qvm/qnx7-arm-guest/p2p.
loc 0x1c0c0000: The base address of the device registers.
intr gic:40: The interrupt number of the current virtual device (see “Common vdev options” in the “Configuration” chapter).
mac aa:aa:aa:aa:aa:aa: The locally-assigned MAC address of the node in the guest.
name p2p: The name of the node in the guest, also specified by the vdevpeer peer option (peer=/dev/qvm/qnx7-arm-guest/p2p).
peer /dev/vdevpeers/vp0: The path to the node in the host, also specified by the vdevpeer bind option (bind=/dev/vdevpeers/vp0).

Start io-pkt-*

Start io-pkt-* in the host, specifying the following for the vdevpeer driver:

io-pkt-v6-hc \
-d vdevpeer peer=/dev/qvm/qnx7-arm-guest/p2p,bind=/dev/vdevpeers/vp0,mac=a0b0c0d0e0f0

where:

peer=: The path to a virtio-net vdev in the guest, inside the /dev/qvm/ directory. The remainder of the path is specified by the virtio-net vdev system option for the guest's directory (qnx7-arm-guest), and, inside this directory, the node in the guest, specifed by the vdev's name option (p2p).
bind=: The path to the node in the host, inside the /dev/vdevpeers/ directory. In this case the default prefix vp is used for node zero (vp0).
mac=: The universally-administered MAC address for the node in the hypervisor host. This MAC address must be a universally-administered address if the node will communicate with the outside world.

Enable the interface

Finally, assuming that you have already enabled an interface on the host. For example:

ifconfig vp0 up
ifconfig vp0 192.168.1.1

you must now enable the interface on the guest and assign it a static IP address in the same subnet as the host. For example, for a QNX Neutrino OS guest:

ifconfig vt0 192.168.1.2

where vt0 is the name of the interface on the guest, vp0 is the peer-to-peer interface on the host, and 192.168.1.2 is an address in the same subnet as the host.

For a Linux guest:

sudo ifconfig enp0s3f0 up
sudo ifconfig enp0s3f0 192.168.1.2

where enp0s3f0 is the peer-to-peer interface, and 192.168.1.2 is an address in the same subnet as the host.