kvmtool: Add minimal support for macvtap
In order to be useable by kvmtool, a macvtap interface requires
some minimal configuration (basically setting up the offload bits).
This requires skipping some of the low level TUN/TAP setup.
To avoid adding yet another option, we extend the 'tapif' option
to detect the use of a file (such as /dev/tap23).
Assuming you've run the following as root:
# ip link add link eth0 name kvmtap0 type macvtap mode bridge
# chgrp kvm /dev/tap$(< /sys/class/net/kvmtap0/ifindex)
# chmod g+rw /dev/tap$(< /sys/class/net/kvmtap0/ifindex)
it is fairly easy to have a script that does the following:
#!/bin/sh
addr=$(< /sys/class/net/kvmtap0/address)
tap=/dev/tap$(< /sys/class/net/kvmtap0/ifindex)
kvmtool/lkvm run --console virtio \
-k /boot/zImage \
-p "console=hvc0 earlyprintk" \
-n trans=mmio,mode=tap,tapif=$tap,guest_mac=$addr
and you now have your VM running, directly attached to the network.
This patch also removes the TUNSETNOCSUM ioctl that has declared
obsolete for quite some time now...
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
1 file changed
