[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [libvirt] [PATCH 1/2] Add VSCSI bus type and VSCSI controller type for pseries guest.

On Fri, May 04, 2012 at 05:49:54PM +0800, Li Zhang wrote:
> On 05/04/2012 05:04 PM, Daniel P. Berrange wrote:
> >On Fri, May 04, 2012 at 10:05:13AM +0800, Li Zhang wrote:
> >>Now, there is only SCSI bus and controller type in libvirt.
> >>And when configuring VSCSI controller, it needs to configure
> >>the spapr-vio bus address type externally. It's a little
> >>inconvenient to configure the controller type.
> >>
> >>This patch is to add VSCSI bus type and VSCSI controller type.
> >>And handle with the problems when VSCSI and SCSI devices
> >>working together, by assign the even number to index of
> >>VSCSI controller and odd number to index of SCSI controller.
> >>
> >>And when the VSCSI controller is always assigned as SPAPRVIO
> >>bus address type and SCSI controller will be always assigned
> >>as PCI bus address, which is implemented according to the
> >>controllers' type.
> >>
> >>So when one disk is based on VSCSI controller, then assign
> >>the bus as 'vscsi', and one right VSCSI controller will be
> >>selected.
> >
> >I'm not at all convinced by this description that we need
> >a new controller type. At most we need a separate<address/>
> >type for the VSCSI controller under an existing SCSI controller
> >element.
> >
> The problem is that when using two kinds of SCSI controller,
> vscsi and scsi, which are based on different address type and
> model at the same time, it needs to specify the model and address
> type externally. And it's hard to find the right controller for
> disk to use, only by the 'sdx'.

Sure, but there's nothing special about s390 / vSCSI in that
respect.  If you have a guest with a SATA controller and a
SCSI controller you have the same problem. If you have multiple
disk controllers assigned to the guest, and are adding a disk,
then you are responsible for providing an <address> element
for the disk to indicate which controller it should be added

The automagic guessing of controllers is only ever intended
to work in the simple case where you have 1 kind of controller

|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]