virgl: disable virgl when no 3D for virtio gpu.

If users are running mesa under old version of qemu or have turned off
GL at runtime, virtio gpu driver actually doesn't work. Adds a detection
here so mesa can fall back to software rendering.

v2:
 - move detection from loader to virgl (Ilia, Emil)

Signed-off-by: Lepton Wu <lepton@chromium.org>
Reviewed-by: Dave Airlie <airlied@redhat.com>

diff --git a/src/gallium/winsys/virgl/drm/virgl_drm_winsys.c b/src/gallium/winsys/virgl/drm/virgl_drm_winsys.c
index cf3c3bac4b4cbf01a070258fdabd766c3f7e8cb8..4198ed7feb3758d14d5e0d8f0c422bafb04793bf 100644 (file)
--- a/src/gallium/winsys/virgl/drm/virgl_drm_winsys.c
+++ b/src/gallium/winsys/virgl/drm/virgl_drm_winsys.c
@@ -800,8 +800,15 @@ virgl_drm_winsys_create(int drmFD)
 {
    struct virgl_drm_winsys *qdws;
    int ret;
+   int gl = 0;
    struct drm_virtgpu_getparam getparam = {0};
 
+   getparam.param = VIRTGPU_PARAM_3D_FEATURES;
+   getparam.value = (uint64_t)(uintptr_t)≷
+   ret = drmIoctl(drmFD, DRM_IOCTL_VIRTGPU_GETPARAM, &getparam);
+   if (ret < 0 || !gl)
+      return NULL;
+
    qdws = CALLOC_STRUCT(virgl_drm_winsys);
    if (!qdws)
       return NULL;
@@ -914,6 +921,10 @@ virgl_drm_screen_create(int fd)
       int dup_fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
 
       vws = virgl_drm_winsys_create(dup_fd);
+      if (!vws) {
+         close(dup_fd);
+         goto unlock;
+      }
 
       pscreen = virgl_create_screen(vws);
       if (pscreen) {