GPU backed BUSE block device

gpu.cpp

#include "buse.h"
#include <CL/cl.hpp>
#include <stdint.h>
#include <vector>

cl::Context context;
cl::Device device;
cl::CommandQueue queue;
cl::Buffer data;

static int vram_read(void* buf, uint32_t len, uint64_t off, void* ud) {
    queue.enqueueReadBuffer(data, true, off, len, buf, nullptr, nullptr);

    return 0;
}

static int vram_write(const void* buf, uint32_t len, uint64_t off, void* ud) {
    queue.enqueueWriteBuffer(data, true, off, len, buf, nullptr, nullptr);

    return 0;
}

static void vram_disc(void* ud) {
    return;
}

static int vram_flush(void* ud) {
    return 0;
}

static int vram_trim(uint64_t off, uint32_t len, void* ud) {
    return 0;
}

// BUSE initialisation
static struct buse_operations operations = {
    .read = vram_read,
    .write = vram_write,
    .disc = vram_disc,
    .flush = vram_flush,
    .trim = vram_trim,
    .size = 1024 * 1024 * 1024
};

int main(int argc, const char* argv[]) {
    // Find OpenCL capable GPU
    std::vector<cl::Platform> platforms;
    cl::Platform::get(&platforms);

    std::vector<cl::Device> devices;
    platforms[0].getDevices(CL_DEVICE_TYPE_GPU, &devices);

    device = devices[0];
    context = cl::Context(device);
    queue = cl::CommandQueue(context, device);

    // Create buffer for data
    data = cl::Buffer(context, CL_MEM_READ_WRITE, operations.size, nullptr, nullptr);

    return buse_main(argv[1], &operations, nullptr);
}

Makefile

gpu: gpu.cpp
	g++ -std=c++11 -O2 -flto -march=native -o gpu gpu.cpp -L. -lbuse -lOpenCL