From fb0e03cbb8e67ce5a88cd18ba3f84d5be82bbd22 Mon Sep 17 00:00:00 2001
From: Xiao Wang <jasowang@redhat.com>
Date: Tue, 7 Jul 2015 09:18:28 +0200
Subject: [PATCH 054/100] virtio: endianness checks for virtio 1.0 devices
Message-id: <1436260751-25015-26-git-send-email-jasowang@redhat.com>
Patchwork-id: 66800
O-Subject: [RHEL7.2 qemu-kvm-rhev PATCH V2 25/68] virtio: endianness checks for virtio 1.0 devices
Bugzilla: 1227343
RH-Acked-by: Michael S. Tsirkin <mst@redhat.com>
RH-Acked-by: David Gibson <dgibson@redhat.com>
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
From: Cornelia Huck <cornelia.huck@de.ibm.com>
Add code that checks for the VERSION_1 feature bit in order to make
decisions about the device's endianness. This allows us to support
transitional devices.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 3c185597c86b8cd0a07c46e7a5bd5aac28bb7200)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
hw/virtio/virtio.c | 6 +++++-
include/hw/virtio/virtio-access.h | 4 ++++
include/hw/virtio/virtio.h | 8 ++++++--
3 files changed, 15 insertions(+), 3 deletions(-)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 8ac6156..d37d27b 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -903,7 +903,11 @@ static bool virtio_device_endian_needed(void *opaque)
VirtIODevice *vdev = opaque;
assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
- return vdev->device_endian != virtio_default_endian();
+ if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+ return vdev->device_endian != virtio_default_endian();
+ }
+ /* Devices conforming to VIRTIO 1.0 or later are always LE. */
+ return vdev->device_endian != VIRTIO_DEVICE_ENDIAN_LITTLE;
}
static bool virtio_64bit_features_needed(void *opaque)
diff --git a/include/hw/virtio/virtio-access.h b/include/hw/virtio/virtio-access.h
index caf0940..cee5dd7 100644
--- a/include/hw/virtio/virtio-access.h
+++ b/include/hw/virtio/virtio-access.h
@@ -19,6 +19,10 @@
static inline bool virtio_access_is_big_endian(VirtIODevice *vdev)
{
+ if (virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+ /* Devices conforming to VIRTIO 1.0 or later are always LE. */
+ return false;
+ }
#if defined(TARGET_IS_BIENDIAN)
return virtio_is_big_endian(vdev);
#elif defined(TARGET_WORDS_BIGENDIAN)
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 8e8b72d..eed7f4f 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -252,7 +252,11 @@ static inline bool virtio_has_feature(VirtIODevice *vdev, unsigned int fbit)
static inline bool virtio_is_big_endian(VirtIODevice *vdev)
{
- assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
- return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
+ if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+ assert(vdev->device_endian != VIRTIO_DEVICE_ENDIAN_UNKNOWN);
+ return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
+ }
+ /* Devices conforming to VIRTIO 1.0 or later are always LE. */
+ return false;
}
#endif
--
1.8.3.1