virtio-gpu: Support DRM native context
Add support for DRM native contexts to VirtIO-GPU. DRM context is enabled using a new virtio-gpu-gl device option "drm_native_context=on". Unlike Virgl and Venus contexts that operate on application API level, DRM native contexts work on a kernel UAPI level. This lower level results in a lightweight context implementations that yield better performance. Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Tested-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com> Reviewed-by: Yiwei Zhang <zzyiwei@gmail.com> Tested-by: Yiwei Zhang <zzyiwei@gmail.com> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Message-ID: <20260303151422.977399-11-dmitry.osipenko@collabora.com> Message-ID: <20260304165043.1437519-13-alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Dmitry Osipenko committed
Mar 4, 2026 at 16:50 UTC
893598209fde32ca5f013a012b120af3a458bcae
5 files changed
+59
docs/system/devices/virtio/virtio-gpu.rst
+11
@@ -84,6 +84,17 @@ of virtio-gpu host memory window. This is typically between 256M and 8G.
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.. _venus: https://gitlab.freedesktop.org/virgl/venus-protocol/
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+DRM native context is supported since release of `virglrenderer`_ v1.0.0
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+using `drm`_ protocol. ``DRM`` virtio-gpu capability set ("capset") requires
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+host blob support (``hostmem`` and ``blob`` fields) and should be enabled
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+using ``drm_native_context`` field. The ``hostmem`` field specifies the size
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+of virtio-gpu host memory window. This is typically between 256M and 8G.
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+
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+.. parsed-literal::
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+ -device virtio-gpu-gl,hostmem=8G,blob=on,drm_native_context=on
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+
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+.. _drm: https://gitlab.freedesktop.org/virgl/virglrenderer/-/tree/main/src/drm
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+
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virtio-gpu rutabaga
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-------------------
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hw/display/virtio-gpu-gl.c
+2
@@ -159,6 +159,8 @@ static const Property virtio_gpu_gl_properties[] = {
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VIRTIO_GPU_FLAG_STATS_ENABLED, false),
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DEFINE_PROP_BIT("venus", VirtIOGPU, parent_obj.conf.flags,
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VIRTIO_GPU_FLAG_VENUS_ENABLED, false),
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+ DEFINE_PROP_BIT("drm_native_context", VirtIOGPU, parent_obj.conf.flags,
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+ VIRTIO_GPU_FLAG_DRM_ENABLED, false),
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};
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static void virtio_gpu_gl_device_unrealize(DeviceState *qdev)
hw/display/virtio-gpu-virgl.c
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@@ -1323,6 +1323,25 @@ int virtio_gpu_virgl_init(VirtIOGPU *g)
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if (virtio_gpu_venus_enabled(g->parent_obj.conf)) {
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flags |= VIRGL_RENDERER_VENUS | VIRGL_RENDERER_RENDER_SERVER;
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}
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+ if (virtio_gpu_drm_enabled(g->parent_obj.conf)) {
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+ flags |= VIRGL_RENDERER_DRM;
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+
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+ if (!(flags & VIRGL_RENDERER_ASYNC_FENCE_CB)) {
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+ /*
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+ * Virglrenderer skips enabling DRM context support without
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+ * enabled async-fence feature. VirtIO-GPU will initialize
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+ * successfully, but DRM context won't be available in guest.
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+ *
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+ * For vrend async-fencing can be enabled only if EGL display
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+ * is used. Vrend can't be disabled in QEMU, hence DRM implicitly
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+ * requires EGL too.
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+ *
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+ * Async-fence was bugged in virglrenderer versions <= 1.1.1.
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+ */
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+ error_report("drm requires egl display and virglrenderer >= 1.2.0");
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+ return -EINVAL;
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+ }
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+ }
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#endif
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ret = virgl_renderer_init(g, flags, &virtio_gpu_3d_cbs);
@@ -1386,5 +1405,14 @@ GArray *virtio_gpu_virgl_get_capsets(VirtIOGPU *g)
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}
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}
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+ if (virtio_gpu_drm_enabled(g->parent_obj.conf)) {
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+ virgl_renderer_get_cap_set(VIRTIO_GPU_CAPSET_DRM,
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+ &capset_max_ver,
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+ &capset_max_size);
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+ if (capset_max_size) {
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+ virtio_gpu_virgl_add_capset(capset_ids, VIRTIO_GPU_CAPSET_DRM);
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+ }
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+ }
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+
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return capset_ids;
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}
hw/display/virtio-gpu.c
+15
@@ -1517,6 +1517,21 @@ void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
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#endif
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}
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+ if (virtio_gpu_drm_enabled(g->parent_obj.conf)) {
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+#ifdef VIRGL_VERSION_MAJOR
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+ #if VIRGL_VERSION_MAJOR >= 1
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+ if (!virtio_gpu_blob_enabled(g->parent_obj.conf) ||
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+ !virtio_gpu_hostmem_enabled(g->parent_obj.conf)) {
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+ error_setg(errp, "drm requires enabled blob and hostmem options");
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+ return;
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+ }
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+ #else
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+ error_setg(errp, "old virglrenderer, drm unsupported");
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+ return;
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+ #endif
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+#endif
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+ }
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+
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if (!virtio_gpu_base_device_realize(qdev,
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virtio_gpu_handle_ctrl_cb,
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virtio_gpu_handle_cursor_cb,
include/hw/virtio/virtio-gpu.h
+3
@@ -100,6 +100,7 @@ enum virtio_gpu_base_conf_flags {
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VIRTIO_GPU_FLAG_RUTABAGA_ENABLED,
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VIRTIO_GPU_FLAG_VENUS_ENABLED,
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VIRTIO_GPU_FLAG_RESOURCE_UUID_ENABLED,
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+ VIRTIO_GPU_FLAG_DRM_ENABLED,
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};
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#define virtio_gpu_virgl_enabled(_cfg) \
@@ -122,6 +123,8 @@ enum virtio_gpu_base_conf_flags {
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(_cfg.hostmem > 0)
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#define virtio_gpu_venus_enabled(_cfg) \
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(_cfg.flags & (1 << VIRTIO_GPU_FLAG_VENUS_ENABLED))
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+#define virtio_gpu_drm_enabled(_cfg) \
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+ (_cfg.flags & (1 << VIRTIO_GPU_FLAG_DRM_ENABLED))
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struct virtio_gpu_base_conf {
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uint32_t max_outputs;