drm_agp_alloc_ioctl
extern int drm_agp_alloc_ioctl(struct drm_device *dev, void *data,
DRM_IOCTL_DEF(DRM_IOCTL_AGP_ALLOC, drm_agp_alloc_ioctl, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
err = drm_agp_alloc_ioctl(dev, (void *)&request, file_priv);