A small prototype I wrote to test writing to GPU memory from the CPU, without going through a burdensome API like Vulkan (it's portable, sure, but pretty heavy for the sole purpose of allocating host visible GPU local memory).

Uses libdrm_amdgpu directly to get a CPU mapping. Using HSA/ROCm here isn't possible for this for whatever reason (on dGPUs at least).

I hope to incorporate this sort of thing into Geobacter so that GPU local memory allocations can be used in Rust Boxes, Vecs etc safely (if not fastly, since, you know, reads have to traverse the PCIE bus) with the usual modern conveniences.