Add VIRTGPU_PARAM_HOST_PAGE_SIZE as a param that can be read with
VIRTGPU_GETPARAM by userspace applications running in the guest to
obtain the host's page size and find out the right alignment to be used
in shared memory allocations.
Signed-off-by: Sergio Lopez <slp@xxxxxxxxxx>
---
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 5 +++++
include/uapi/drm/virtgpu_drm.h | 1 +
2 files changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index e4f76f315550..c16cdf2d64b4 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -117,6 +117,11 @@ static int virtio_gpu_getparam_ioctl(struct drm_device *dev, void *data,
case VIRTGPU_PARAM_EXPLICIT_DEBUG_NAME:
value = vgdev->has_context_init ? 1 : 0;
break;
+ case VIRTGPU_PARAM_HOST_PAGE_SIZE:
+ if (!vgdev->has_host_page_size)
+ return -EINVAL;
+ value = vgdev->host_page_size;
+ break;
default:
return -EINVAL;
}
diff --git a/include/uapi/drm/virtgpu_drm.h b/include/uapi/drm/virtgpu_drm.h
index c2ce71987e9b..505f87263a15 100644
--- a/include/uapi/drm/virtgpu_drm.h
+++ b/include/uapi/drm/virtgpu_drm.h
@@ -98,6 +98,7 @@ struct drm_virtgpu_execbuffer {
#define VIRTGPU_PARAM_CONTEXT_INIT 6 /* DRM_VIRTGPU_CONTEXT_INIT */
#define VIRTGPU_PARAM_SUPPORTED_CAPSET_IDs 7 /* Bitmask of supported capability set ids */
#define VIRTGPU_PARAM_EXPLICIT_DEBUG_NAME 8 /* Ability to set debug name from userspace */
+#define VIRTGPU_PARAM_HOST_PAGE_SIZE 9 /* Host's page size */
struct drm_virtgpu_getparam {
__u64 param;
--
2.45.2
