Re: [libvirt] [Qemu-devel] Re: Supporting hypervisor specific APIs in libvirt
On 03/23/2010 08:00 PM, Avi Kivity wrote:
On 03/23/2010 06:06 PM, Anthony Liguori wrote:
>> I thought the monitor protocol *was* our API. If not, why not?
>
> It is. But our API is missing key components like guest
> enumeration. So the fundamental topic here is, do we introduce these
> missing components to allow people to build directly to our interface
> or do we make use of the functionality that libvirt already provides
> if they can plumb our API directly to users.
>
Guest enumeration is another API.
Over the kvm call I suggested a qemu concentrator that would keep
track of all running qemus, and would hand out monitor connections to
users. It can do the enumeration (likely using qmp). Libvirt could
talk to that, like it does with other hypervisors.
To elaborate
qemud
- daemonaizes itself
- listens on /var/lib/qemud/guests for incoming guest connections
- listens on /var/lib/qemud/clients for incoming client connections
- filters access according to uid (SCM_CREDENTIALS)
- can pass a new monitor to client (SCM_RIGHTS)
- supports 'list' command to query running guests
- async messages on guest startup/exit
qemu
- with -qemud option, connects to qemud (or maybe automatically?)
qemudc
- command-line client, can access qemu human monitor
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.