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;
}

View File

@ -1175,7 +1175,9 @@ static uint64_t virtio_pci_common_read(void *opaque, hwaddr addr,
break;
case VIRTIO_PCI_COMMON_DF:
if (proxy->dfselect <= 1) {
val = (vdev->host_features & ~VIRTIO_LEGACY_FEATURES) >>
VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
val = (vdev->host_features & ~vdc->legacy_features) >>
(32 * proxy->dfselect);
}
break;

View File

@ -2214,6 +2214,8 @@ static void virtio_device_class_init(ObjectClass *klass, void *data)
dc->props = virtio_properties;
vdc->start_ioeventfd = virtio_device_start_ioeventfd_impl;
vdc->stop_ioeventfd = virtio_device_stop_ioeventfd_impl;
vdc->legacy_features |= VIRTIO_LEGACY_FEATURES;
}
bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev)

View File

@ -113,6 +113,11 @@ typedef struct VirtioDeviceClass {
void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
void (*reset)(VirtIODevice *vdev);
void (*set_status)(VirtIODevice *vdev, uint8_t val);
/* For transitional devices, this is a bitmap of features
* that are only exposed on the legacy interface but not
* the modern one.
*/
uint64_t legacy_features;
/* Test and clear event pending status.
* Should be called after unmask to avoid losing events.
* If backend does not support masking,