[Libvir] [PATCH][RFC] libvirt ldoms support

[Daniel P. Berrange]

On Wed, Apr 09, 2008 at 12:52:33PM +0100, Richard W.M. Jones wrote:
> On Tue, Apr 08, 2008 at 10:49:01AM -0700, Ryan Scott wrote:
> > @@ -1794,11 +1802,17 @@ virDomainGetUUID(virDomainPtr domain, un
> >          return (-1);
> >      }
> >  
> > +#ifndef WITH_LDOMS
> >      if (domain->id == 0) {
> >          memset(uuid, 0, VIR_UUID_BUFLEN);
> >      } else {
> >          memcpy(uuid, &domain->uuid[0], VIR_UUID_BUFLEN);
> >      }
> > +#endif
> > +
> > +#ifdef WITH_LDOMS
> > +    memcpy(uuid, &domain->uuid[0], VIR_UUID_BUFLEN);
> > +#endif
> >      return (0);
> >  }
> >  
> 
> I guess this is working around the Xen assumption that dom0 has UUID
> 0000-0000-0000-0000, so it exposes a Xen-ism in the code.  This should
> move down to the Xen driver, so I'll propose a patch to fix that,
> which should remove the need for the specific #ifdef here.

Yeah, I recall discussing this before. IIRC, we determined that the
domain object will alwayss have a valid UUID, therefore the explicit

  memset(uuid, 0, VIR_UUID_BUFLEN);

is legacy code & redundant.

> > @@ -5025,6 +5039,42 @@ virStorageVolGetPath(virStorageVolPtr vo
> >      return NULL;
> >  }
> >  
> > +#ifdef WITH_LDOMS
> > +/** 
> > + * virLDomConsole:
> > + * @domain: the domain if available
> [...]
> 
> I think having a generic "get console" call in libvirt might be a good
> idea, but having public LDom-specific calls isn't.  Dan Berrange will
> correct me if I'm wrong here, but currently the method used is to dump
> the domain XML of a domain and look for the <console/> or <graphics/>
> element within <devices/>, corresponding to the serial console or the
> graphical (VNC) console respectively.
> 
> For example it might look like:
> 
>     <graphics type='vnc' port='5904'/>
> 
> (see full example at http://libvirt.org/format.html).  So can you add
> a similar device to the LDom domain XML to avoid the need for this new
> call?
> 
> >From reading the virsh code it looks like virLDomConsole is meant to
> return the telnet port number for the serial console(?) so perhaps
> something like:
> 
>   <console port='1234'/>

The <console> tag only allows for PTYs currently, but I'm parttime
hacking on this more general proposal too

http://www.redhat.com/archives/libvir-list/2007-May/msg00191.html

which allows for TCP access to console, so I think we can come up
with something which works for LDoms too.


Dan.
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