virtio-msg: define notification, polling, and ordering model

Clarify how EVENT_AVAIL, EVENT_CONFIG, and EVENT_USED are used when
endpoints choose event-driven notifications versus polling-only
operation, and make any bus-side forwarding, polling, or synthesized
delivery transparent to the transport-visible semantics.

Also define the EVENT_AVAIL notification-data encoding, require per
driver/device request ordering through the bus plus receive-order
processing at the device, and fold the related conformance references
into the same patch.

Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>

Author: bertrand-marquis

conformance.tex

@@ -177,12 +177,13 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_SET_DRIVER_FEATURES / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_CONFIG / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_SET_CONFIG / Driver}
+\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_DEVICE_STATUS / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_SET_DEVICE_STATUS / Driver}
+\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_VQUEUE / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_SET_VQUEUE / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_RESET_VQUEUE / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_CONFIG / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_AVAIL / Driver}
-\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_USED / Driver}
 \end{itemize}
 
 \input{device-types/net/driver-conformance.tex}
@@ -314,7 +315,6 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_RESET_VQUEUE / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_SHM / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_CONFIG / Device}
-\item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_USED / Device}
 \end{itemize}
 
 \input{device-types/net/device-conformance.tex}
@@ -360,8 +360,6 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Basic Concepts / Common Message Format / Bus}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Basic Concepts / Ordering / Bus}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Device Discovery / Bus}
-\item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Driver Notifications / Bus}
-\item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Device Notifications / Bus}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / Runtime Notifications / Bus}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Hotplug and Removal / Bus}
 \item \ref{busnormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_EVENT_AVAIL / Bus}