Sv39 Rust Implementation

Sv39 is one of RISCV's paging systems, with 39-bit virtual addresses and a total address space of 512 GB.

Get Started!

One of the simplest examples is the dummy kernel found in the source code, which performs a 1:1 mapping without the higher half.

  let kernel_base = (&raw mut __kernel_base) as u64;
  let heap_end = (&raw mut __heap_end) as u64; // OR KERNEL_END
  let offset_mapper = sv39::page::mapper::OffsetMapper::identity();
  offset_mapper
       .map_range(
                Page::new(VirtAddr::new(kernel_base).unwrap()),
                Page::new(VirtAddr::new(heap_end).unwrap()),
                PhysFrame::new(PhysAddr::new(kernel_base).unwrap()),
                PhysFrame::new(PhysAddr::new(heap_end).unwrap()),
                false,
                PageFlags::X | PageFlags::R | PageFlags::W | PageFlags::V,
                &level_2_page_table,
                &mut allocator,
            )
            .unwrap();
        println!("Loading paging");
        load_with_phys(&level_2_page_table, None);

Resources

• Inspired in: https://github.com/rust-osdev/x86_64/
• RiscV oficial docs: https://docs.riscv.org/reference/isa/v20260120/priv/supervisor.html#sv39