From 53b9bba9fc087489b4ffdd0aa37eb802a6c22693 Mon Sep 17 00:00:00 2001
From: mstsirkin <mstsirkin@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652>
Date: Sun, 2 Mar 2014 21:35:56 +0000
Subject: legacy virtqueue layout: confirmance

Change accepted on VIRTIO TC Meeting, 3 December 2013

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@298 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652
---
 content.tex | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

(limited to 'content.tex')

diff --git a/content.tex b/content.tex
index 9276d9b..75e80b5 100644
--- a/content.tex
+++ b/content.tex
@@ -318,7 +318,11 @@ Descriptor Table & Available Ring (\ldots padding\ldots) & Used Ring \\
 \end{tabular}
 
 The bus-specific Queue Size field controls the total number of bytes
-required for the virtqueue according to the following formula:
+required for the virtqueue.
+When using the legacy interface, the transitional
+driver MUST retrieve the Queue Size field from the device
+and MUST allocate the total number of bytes for the virtuqueue
+according to the following formula:
 
 \begin{lstlisting}
 #define ALIGN(x) (((x) + PAGE_SIZE) & ~PAGE_SIZE)
@@ -330,7 +334,9 @@ static inline unsigned vring_size(unsigned int qsz)
 \end{lstlisting}
 
 This wastes some space with padding.
-The legacy virtqueue layout structure therefore looks like this:
+When using the legacy interface, both transitional
+devices and drivers MUST use the following virtqueue layout
+structure to locate elements of the virtqueue:
 
 \begin{lstlisting}
 struct vring {
-- 
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