[PATCH RFC v7 1/8] Introduce device group

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

From: Max Gurtovoy <mgurtovoy@nvidia.com>

Each device group has a type. For now, define one initial type of device
groups: SR-IOV type.

SR-IOV type - A virtio PCI SR-IOV physical function (PF) and its
PCI SR-IOV virtual functions (VFs). This group may contain one or more
virtio devices.

Each device group has a unique identifier. This identifier is the group
identifier.

Each device within a device group has a unique identifier. This identifier
is the group member identifier.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
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 content.tex |  2 ++
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 create mode 100644 admin.tex

diff --git a/admin.tex b/admin.tex
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--- /dev/null
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@@ -0,0 +1,49 @@
+\section{Device groups}\label{sec:Basic Facilities of a Virtio Device / Device groups}
+
+It is occasionally useful to have a device control a group of
+other devices. Terminology used in such cases:
+
+\begin{description}
+\item[Device group]
+        or just group, includes zero or more devices.
+\item[Parent device]
+        or parent, the device controlling the group.
+\item[Member device]
+        a device within a group. Parent device itself may, or may
+	not be a member of the group.
+\item[Member identifier]
+        each member has this indentifier, unique within the group
+	and used to address it through the parent device.
+\item[Group type]
+	specifies what kind of member devices there are in a
+	group, how is the member identifier intepreted
+	and what kind of control does the parent have.
+\item[Group identifier]
+	each group has this identifier, unique within the parent device.
+	this specifies the group type and possibly selects the
+	group if multiple groups of the same type can be controlled by the same
+	parent device.
+\end{description}
+
+A single group type is currently specified:
+\begin{description}
+\item[SR-IOV group type]
+This device group has a PCI Single Root I/O Virtualization
+(SR-IOV) physical function (PF) device as a parent and includes
+all its SR-IOV virtual functions (VFs) as members (see
+\hyperref[intro:PCIe]{[PCIe]}).
+
+The PF device itself is not a member of the group.
+
+At most one group of this type can exist per PF, and
+the group identifier for a group of this type is always 0x1.
+
+A member identifier for this group can have a value 0x1 to 0xFFFF
+and equals the SR-IOV VF number of the member device (see
+\hyperref[intro:PCIe]{[PCIe]}).
+
+Both parent and member devices for this group type use the Virtio
+PCI transport (see \ref{sec:Virtio Transport Options / Virtio Over PCI Bus}).
+\end{description}
+
+
diff --git a/content.tex b/content.tex
index e863709..6e26dff 100644
--- a/content.tex
+++ b/content.tex
@@ -449,6 +449,8 @@ \section{Exporting Objects}\label{sec:Basic Facilities of a Virtio Device / Expo
 types. It is RECOMMENDED that devices generate version 4
 UUIDs as specified by \hyperref[intro:rfc4122]{[RFC4122]}.
 
+\input{admin.tex}
+
 \chapter{General Initialization And Device Operation}\label{sec:General Initialization And Device Operation}
 
 We start with an overview of device initialization, then expand on the
-- 
MST