[libvirt] [PATCH] domaincaps: Expose UEFI capability

[Michal Privoznik]

On 16.09.2014 17:11, Cole Robinson wrote:
> On 09/16/2014 09:44 AM, Michal Privoznik wrote:
>> As of 542899168c38 we learned libvirt to use UEFI for domains.
>> However, management applications may firstly query if libvirt
>> supports it. And this is where virConnectGetDomainCapabilities()
>> API comes handy.
>>
>> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
>
> Tested-by: Cole Robinson <crobinso at redhat.com>
> Acked-by: Cole Robinson <crobinso at redhat.com>

Thanks. I'll push this one shortly.

>
> So this exposes that qemu + libvirt have the required support to use OVMF.
>
> The other bit virt-manager would like is to know the paths to the OVMF
> binaries. Preferably with some way to tell if they actually exist on disk,
> which might just be hiding them from the XML if they aren't found, or an extra
> XML property.
>
> As you mentioned in the virt-tools-list email, you probably don't need to
> expose the vars template file path, and just the OVMF binary path.
>
> Thoughts on what the XML might look like? Doesn't seem like there's any
> existing precedence in domcapabilities schema

Correct. domcapabilities is not very mature atm. With this patch, its 
output should look like this:

<domainCapabilities>
   <snip/>
   <os supported='yes'>
     <loader supported='yes'>
       <enum name='type'>
         <value>rom</value>
         <value>pflash</value>
       </enum>
       <enum name='readonly'>
         <value>yes</value>
         <value>no</value>
       </enum>
     </loader>
   </os>
   <devices/>
</domainCapabilities>

How about introducing <nvram/> under the <os/> (like it is in the domain 
XML)? Something like the following:

   <os supported='yes'>
     <loader supported='yes'>
       <enum name='type'>
         <value>rom</value>
         <value>pflash</value>
       </enum>
       <enum name='readonly'>
         <value>yes</value>
         <value>no</value>
       </enum>
     </loader>
     <nvram supported='yes'>
       <value>/usr/share/OVMF/OVMF_VARS.fd</value>
       <value>/other/files/from/libvirtd.config</value>
       ...
     </nvram>
   </os>

As you've probably guessed, the <nvram/>'s <value/> would repeat itself 
for every VARS file known to libvirt. Or should we enclose these into an 
<enum/> and make it child of the <nvram/>? What should the enum be 
called then? Or even better - shall the <nvram/> be turned into <enum 
name='nvram'/>?

Michal