This patch is in response to
https://bugzilla.redhat.com/show_bug.cgi?id=643050
The existing libvirt support for the vhost-net backend to the virtio
network driver happens automatically - if the vhost-net device is
available, it is always enabled, otherwise the standard userland
virtio backend is used.
This patch makes it possible to force whether or not vhost-net is used
with a bit of XML. Adding a <driver> element to the interface XML, eg:
<interface type="network">
<model type="virtio"/>
<driver name="vhost"/>
will force use of vhost-net (if it's not available, the domain will
fail to start). if driver name="qemu", vhost-net will not be used even
if it is available.
If there is no <driver name='xxx'/> in the config, libvirt will revert
to the pre-existing automatic behavior - use vhost-net if it's
available, and userland backend if vhost-net isn't available.
Move the code for handling the QEMU virDomainObjPtr private
data, and custom XML namespace into a separate file
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: New file
for private data & namespace code
* src/qemu/qemu_driver.c, src/qemu/qemu_driver.h: Remove
private data & namespace code
* src/qemu/qemu_driver.h, src/qemu/qemu_command.h: Update
includes
* src/Makefile.am: Add src/qemu/qemu_domain.c
The qemu_conf.c code is doing three jobs, driver config file
loading, QEMU capabilities management and QEMU command line
management. Move the command line code into its own file
* src/qemu/qemu_command.c, src/qemu/qemu_command.h: New
command line management code
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Delete command
line code
* src/qemu/qemu_conf.h, src/qemu_conf.c: Adapt for API renames
* src/Makefile.am: add src/qemu/qemu_command.c
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_text.c: Add
import of qemu_command.h
