drm/virtio: Allow importing prime buffers when 3D is enabled

[ Upstream commit df4dc94 ]

This functionality was added for using a KMS-only virtgpu with a physical
(or SR-IOV) headless GPU in passthrough, but it should not be restricted
to KMS-only mode. It can be used with cross-domain to pass guest memfds
to the host compositor with zero copies (using udmabuf on both sides).

Drop the check for the absence of virgl_3d to allow for more use cases.

Fixes: ca77f27 ("drm/virtio: Import prime buffers from other devices as guest blobs")
Signed-off-by: Val Packett <val@invisiblethingslab.com>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patch.msgid.link/20251210154755.1119861-2-val@invisiblethingslab.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: valpackett

drivers/gpu/drm/virtio/virtgpu_prime.c

@@ -312,7 +312,7 @@ struct drm_gem_object *virtgpu_gem_prime_import(struct drm_device *dev,
 		}
 	}
 
-	if (!vgdev->has_resource_blob || vgdev->has_virgl_3d)
+	if (!vgdev->has_resource_blob)
 		return drm_gem_prime_import(dev, buf);
 
 	bo = kzalloc(sizeof(*bo), GFP_KERNEL);