[Libvir] [PATCH] Add virConnectGetCapabilities call to return the capabilities of the driver / hypervisor

9 Mar 2007

      This patch:

* Adds virConnectGetCapabilities which returns an XML description of the 
capabilities of the driver or hypervisor under this connection (see 
below for more about the XML format).

* Adds virsh capabilities command.

* Checks the Python binding works.

Caveats:

* Xen implementation (in xen_internal.c) is not tested because I don't 
have a working Xen machine right now.  QEMU, test and remote work however.

Example:

$ virsh -c test:///default capabilities | tidy -xml -i -q
<capabilities>
   <domain>
     <type>test</type>
   </domain>
   <host_features></host_features>
   <guest_architectures>
     <guest_architecture>
       <model>i686</model>
       <bits>32</bits>
       <guest_features>
         <accelerated />
         <pae />
       </guest_features>
     </guest_architecture>
   </guest_architectures>
</capabilities>

$ virsh -c qemu:///session capabilities | tidy -xml -i -q
<capabilities>
   <domain>
     <type>qemu</type>
   </domain>
   <guest_architectures>
     <guest_architecture>
       <model>i686</model>
       <bits>32</bits>
       <features>
         <emulated />
       </features>
     </guest_architecture>
     <guest_architecture>
       <model>x86_64</model>
       <bits>64</bits>
       <features>
         <emulated />
       </features>
     </guest_architecture>
[... other archs deleted ...]
   </guest_architectures>
</capabilities>

XML format:

The <capabilities> node contains information about the host and a list 
of supported architectures for guests.  About the host we return:

   <domain>
     <type>	The default type acceptable when creating a domain.

   <host_features>
     <hvm>	Does the host CPU support HVM?
       <type>	Type of HVM (eg. "vmx")
       <bios_setting>   "enabled" or "disabled"

About the guest architectures we can return:

   <guest_architecture>
     <model>	The (virtualised) CPU
     <bits>      Bits
     <domain>
       <type>	If different from the default type (eg. for kqemu)
     <features>
       <hvm>		Full virt guest?
       <accelerated>	Accelerated (eg. Xen or kqemu)
       <emulated>	Emulated (eg. qemu or bochs)
       (and a few other esoteric flags here)

Rich.

-- 
Emerging Technologies, Red Hat  http://et.redhat.com/~rjones/
64 Baker Street, London, W1U 7DF     Mobile: +44 7866 314 421
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  and make dark of the things which are in their nature excessively
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[Libvir] [PATCH] Add virConnectGetCapabilities call to return the capabilities of the driver / hypervisor

Richard W.M. Jones