Re: Mask bit support's API

[Gleb Natapov <gleb@redhat.com>]

On Tue, Nov 23, 2010 at 05:11:19PM +0200, Michael S. Tsirkin wrote:
> On Tue, Nov 23, 2010 at 04:06:20PM +0200, Avi Kivity wrote:
> > >>
> > >>  So instead of
> > >>
> > >>  - guest reads/writes msix
> > >>  - kvm filters mmio, implements some, passes others to userspace
> > >>
> > >>  we have
> > >>
> > >>  - guest reads/writes msix
> > >>  - kvm implements all
> > >>  - some writes generate an additional notification to userspace
> > >
> > >I suppose we don't need to generate notification to userspace? Because every
> > >read/write is handled by kernel, and userspace just need interface to kernel to
> > >get/set the entry - and well, does userspace need to do it when kernel can handle
> > >all of them? Maybe not...
> > 
> > We could have the kernel handle addr/data writes by setting up an
> > internal interrupt routing.  A disadvantage is that more work is
> > needed if we emulator interrupt remapping in qemu.
> 
> As an alternative, interrupt remapping will need some API rework, right?
> Existing APIs only pass address/data for msi.
> 
IIRC interrupt remapping works with address/data to. It just interpret
it differently from apic.

--
			Gleb.