.rs

let index_buffer_data = [0u32, 1, 2];

// Allocate the index buffer
let index_buffer_info = vk::BufferCreateInfo::builder()
    .size(size_of_val(&index_buffer_data) as u64)
    .usage(vk::BufferUsageFlags::TRANSFER_SRC)
    .sharing_mode(vk::SharingMode::EXCLUSIVE);
let create_info = AllocationCreateInfo {
    usage: MemoryUsage::CpuOnly,
    flags: AllocationCreateFlags::MAPPED,
    ..Default::default()
};
let (index_buffer, index_allocation, index_allocation_info) = allocator
    .create_buffer(&index_buffer_info, &create_info).unwrap();