virtio: allow per-device-class legacy features

Legacy features are those that transitional devices only
expose on the legacy interface.
Allow different ones per device class.

Cc: qemu-stable@nongnu.org # dependency for the next patch
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This commit is contained in:
Michael S. Tsirkin 2016-11-04 12:04:23 +02:00
parent 1b39bc1cf6
commit 9b706dbbbb
4 changed files with 13 additions and 2 deletions

View file

@ -303,6 +303,8 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
if (!ccw.cda) {
ret = -EFAULT;
} else {
VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
features.index = address_space_ldub(&address_space_memory,
ccw.cda
+ sizeof(features.features),
@ -312,7 +314,7 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
if (dev->revision >= 1) {
/* Don't offer legacy features for modern devices. */
features.features = (uint32_t)
(vdev->host_features & ~VIRTIO_LEGACY_FEATURES);
(vdev->host_features & ~vdc->legacy_features);
} else {
features.features = (uint32_t)vdev->host_features;
}