@@ -748,6 +748,11 @@ static void vhost_log_stop(MemoryListener *listener,
/* FIXME: implement */
}
+/* The vhost driver natively knows how to handle the vrings of non
+ * cross-endian legacy devices and modern devices. Only legacy devices
+ * exposed to a bi-endian guest may require the vhost driver to use a
+ * specific endianness.
+ */
static inline bool vhost_needs_vring_endian(VirtIODevice *vdev)
{
if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
@@ -755,9 +760,9 @@ static inline bool vhost_needs_vring_endian(VirtIODevice *vdev)
}
#ifdef TARGET_IS_BIENDIAN
#ifdef HOST_WORDS_BIGENDIAN
- return !virtio_is_big_endian(vdev);
+ return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE;
#else
- return virtio_is_big_endian(vdev);
+ return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;
#endif
#else
return false;
After the call to virtio_vdev_has_feature(), we only care for legacy devices, so we don't need the extra check in virtio_is_big_endian(). Also the device_endian field is always set (VIRTIO_DEVICE_ENDIAN_UNKNOWN may only happen on a virtio_load() path that cannot lead here), so we don't need the assert() either. This open codes the device_endian checking in vhost_needs_vring_endian(). It also adds a comment to explain the logic, as recent reviews showed the cross-endian tweaks aren't that obvious. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> --- hw/virtio/vhost.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)