Re: [PATCH v9 08/16] split-ring: generalize text

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Mar 07, 2018 at 12:00:48PM +0100, Cornelia Huck wrote:
> On Thu, 1 Mar 2018 01:31:33 +0200
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > Update generic text to talk about available/used buffers, not rings.
> > Move some split-ring specific text to the correct section.
> > 
> > Update conformance section with link to the new conformance clause.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >  conformance.tex |  1 +
> >  content.tex     | 10 ++++------
> >  split-ring.tex  |  4 ++++
> >  3 files changed, 9 insertions(+), 6 deletions(-)
> > 
> > diff --git a/conformance.tex b/conformance.tex
> > index 55d17b4..e4efe33 100644
> > --- a/conformance.tex
> > +++ b/conformance.tex
> > @@ -38,6 +38,7 @@ A driver MUST conform to the following normative statements:
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Descriptor Table}
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Descriptor Table / Indirect Descriptors}
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / Virtqueue Interrupt Suppression}
> > +\item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Available Ring}
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Used Ring}
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / Virtqueue Notification Suppression}
> >  \item \ref{drivernormative:Basic Facilities of a Virtio Device / Virtqueues / Supplying Buffers to The Device / Updating idx}
> > diff --git a/content.tex b/content.tex
> > index 5634c7d..e1e30a0 100644
> > --- a/content.tex
> > +++ b/content.tex
> > @@ -381,12 +381,10 @@ of a device are live once the device has been reset.
> >  
> >  \drivernormative{\subsection}{Device Cleanup}{General Initialization And Device Operation / Device Cleanup}
> >  
> > -A driver MUST NOT alter descriptor table entries which have been
> > -exposed in the available ring (and not marked consumed by the device
> > -in the used ring) of a live virtqueue.
> > -
> > -A driver MUST NOT decrement the available \field{idx} on a live virtqueue (ie.
> > -there is no way to ``unexpose'' buffers).
> > +A driver MUST NOT alter virtqueue entries for exposed buffers -
> > +i.e. buffers which have been
> > +made available to the device (and not been used by the device)
> > +of a live virtqueue.
> >  
> >  Thus a driver MUST ensure a virtqueue isn't live (by device reset) before removing exposed buffers.
> >  
> > diff --git a/split-ring.tex b/split-ring.tex
> > index 9601a53..a594d41 100644
> > --- a/split-ring.tex
> > +++ b/split-ring.tex
> > @@ -296,6 +296,10 @@ referred to this structure as vring_avail, and the constant as
> >  VRING_AVAIL_F_NO_INTERRUPT, but the layout and value were identical.
> >  \end{note}
> >  
> > +\drivernormative{\subsubsection}{The Virtqueue Available Ring}{Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Available Ring}
> > +A driver MUST NOT decrement the available \field{idx} on a virtqueue (ie.
> 
> s/ie./i.e./
> 
> as you're touching it anyway.

I forgot to address this. Sorry. Let's do it as a patch on top.

> 
> > +there is no way to ``unexpose'' buffers).
> > +
> >  \subsection{Virtqueue Interrupt Suppression}\label{sec:Basic Facilities of a Virtio Device / Virtqueues / Virtqueue Interrupt Suppression}
> >  
> >  If the VIRTIO_F_EVENT_IDX feature bit is not negotiated,
> 
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>