virtio-msg: tighten configuration, status, and EVENT_CONFIG semantics

Align configuration generation handling, SET_CONFIG, EVENT_CONFIG, and
device-status behavior more closely with the core virtio model.

Make nonzero SET_CONFIG writes all-or-nothing, keep strict generation
mismatch handling optional, add explicit driver rules for
GET_DEVICE_STATUS and GET_VQUEUE, and limit EVENT_CONFIG status
notifications to device-originated asynchronous changes.

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

Author: bertrand-marquis

conformance.tex

@@ -162,15 +162,11 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Overview / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Device Information / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Device Features / Driver}
-\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Device Configuration / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Virtqueue Configuration / Driver}
-\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Status Information / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Finalizing Initialization / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Driver Notifications / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Device Notifications / Driver}
-\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Configuration Changes During Operation / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Virtqueue Changes During Operation / Driver}
-\item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Reset / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / Mandatory / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_DEVICE_INFO / Driver}
 \item \ref{drivernormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_DEVICE_FEATURES / Driver}
@@ -182,7 +178,6 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \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}
 \end{itemize}
 
@@ -294,14 +289,10 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Basic Concepts / Common Message Format / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Basic Concepts / Ordering / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Device Features / Device}
-\item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Device Configuration / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Virtqueue Configuration / Device}
-\item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Status Information / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Initialization / Finalizing Initialization / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Device Notifications / Device}
-\item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Configuration Changes During Operation / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Virtqueue Changes During Operation / Device}
-\item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Device Operation / Reset / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / Mandatory / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_DEVICE_INFO / Device}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_GET_CONFIG / Device}
@@ -312,7 +303,6 @@ \section{Conformance Targets}\label{sec:Conformance / Conformance Targets}
 \item \ref{devicenormative:Virtio Transport Options / Virtio Over Messages / Transport Messages / VIRTIO_MSG_SET_VQUEUE / Device}
 \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}
 \end{itemize}
 
 \input{device-types/net/device-conformance.tex}