Re: [Qemu-devel] [PATCH 6/6] spec/vhost-user spec: Add IOMMU support

[Michael S. Tsirkin]

On Tue, May 16, 2017 at 10:19:24AM +0200, Maxime Coquelin wrote:
> 
> 
> On 05/12/2017 04:21 PM, Maxime Coquelin wrote:
> > 
> > 
> > On 05/11/2017 08:25 PM, Michael S. Tsirkin wrote:
> > > On Thu, May 11, 2017 at 02:32:46PM +0200, Maxime Coquelin wrote:
> > > > This patch specifies and implements the master/slave communication
> > > > to support device IOTLB in slave.
> > > > 
> > > > The vhost_iotlb_msg structure introduced for kernel backends is
> > > > re-used, making the design close between the two backends.
> > > > 
> > > > An exception is the use of the secondary channel to enable the
> > > > slave to send IOTLB miss requests to the master.
> > > > 
> > > > Signed-off-by: Maxime Coquelin <address@hidden>
> > > > ---
> > > >   docs/specs/vhost-user.txt | 75
> > > > +++++++++++++++++++++++++++++++++++++++++++++++
> > > >   hw/virtio/vhost-user.c    | 31 ++++++++++++++++++++
> > > >   2 files changed, 106 insertions(+)
> > > > 
> > > > diff --git a/docs/specs/vhost-user.txt b/docs/specs/vhost-user.txt
> > > > index 5fa7016..4a1f0c3 100644
> > > > --- a/docs/specs/vhost-user.txt
> > > > +++ b/docs/specs/vhost-user.txt
> > > > @@ -97,6 +97,23 @@ Depending on the request type, payload can be:
> > > >      log offset: offset from start of supplied file descriptor
> > > >          where logging starts (i.e. where guest address 0 would
> > > > be logged)
> > > > + * An IOTLB message
> > > > +   ---------------------------------------------------------
> > > > +   | iova | size | user address | permissions flags | type |
> > > > +   ---------------------------------------------------------
> > > > +
> > > > +   IOVA: a 64-bit guest I/O virtual address
> > > 
> > > guest -> VM
> > 
> > Ok.
> 
> It seems that VM is never used in the doc, but guest is:
> $ grep -i guest docs/specs/vhost-user.txt | wc -l
> 13
> grep -i vm docs/specs/vhost-user.txt | wc -l
> 0
> 
> I think I should keep "guest" for consistency?
> 
> Thanks,
> Maxime

"I/O virtual address programmed by the guest" ?