vo_gpu: vulkan: Add support for exporting buffer memory

The CUDA/Vulkan interop works on the basis of memory being exported
from Vulkan and then imported by CUDA. To enable this, we add a way
to declare a buffer as being intended for export, and then add a
function to do the export.

For now, we support the fd and Handle based exports on Linux and
Windows respectively. There are others, which we can support when
a need arises.

Also note that this is just for exporting buffers, rather than
textures (VkImages). Image import on the CUDA side is supposed to
work, but it is currently buggy and waiting for a new driver release.

Finally, at least with my nvidia hardware and drivers, everything
seems to work even if we don't initialise the buffer with the right
exportability options. Nevertheless I'm enforcing it so that we're
following the spec.

1 files changed, 4 insertions, 0 deletions

diff --git a/video/out/vulkan/common.h b/video/out/vulkan/common.h
index 1a4c3b842f..a4284f9055 100644
--- a/video/out/vulkan/common.h
+++ b/video/out/vulkan/common.h
@@ -73,4 +73,8 @@ struct mpvk_ctx {
     // Cached capabilities
     VkPhysicalDeviceLimits limits;
     VkPhysicalDeviceFeatures features;
+
+    // Extension availability
+    bool has_ext_external_memory;
+    bool has_ext_external_memory_export;
 };