# kvm-rs

[![Rust][wf-badge]][wf-output] [![Rustdoc][doc-badge]][doc-html]

[wf-output]: https://github.com/johannst/mini-kvm-rs/actions/workflows/rust.yml
[wf-badge]: https://github.com/johannst/mini-kvm-rs/actions/workflows/rust.yml/badge.svg
[doc-html]: https://johannst.github.io/mini-kvm-rs/kvm_rs/index.html
[doc-badge]: https://img.shields.io/badge/kvm__rs-rustdoc-blue.svg?style=flat&logo=rust

A playground for the [`Kernel Virtual Machine
(KVM)`](https://www.kernel.org/doc/html/latest/virt/kvm/index.html) in rust to
learn about `KVM`, [`rust
ffi`](https://doc.rust-lang.org/stable/std/ffi/index.html) and `x86_64`.

The sources are structured as follows:
- [`src/`](./src) provides a small library as abstraction over the raw [KVM
  API](https://www.kernel.org/doc/html/latest/virt/kvm/api.html#api-description).
- [`examples/`](./examples) contains example VMs using the library above.
- [`guest/`](./guest) contains the guest source code which is run inside the VMs.
- [`sysdeps/`](./sysdeps) contains helper to generate some KVM constants from
  the system header (executed by [build.rs](./build.rs)).

## Documentation

Rustdoc for this crate is avalable at
[johannst.github.io/mini-kvm-rs][doc-html].

## Requirements

- Kernel with `kvm` support and permissions to open `/dev/kvm`.
- Compiler & binuitls for generating the guest images.

## Real Mode (16bit) example

Runs the [real mode VM](./examples/real_mode.rs) with the [guest program](./guest/guest16.S).

```bash
# Once: Build the guest binary image.
make -C guest

# Run the Real Mode example.
cargo run --example real_mode
```

## Long Mode (64bit) example

Runs the [long mode VM](./examples/long_mode.rs) with the [guest program](./guest/guest64.S).

```bash
# Once: Build the guest binary image.
make -C guest

# Run the Long Mode example.
cargo run --example long_mode
```

## License
This project is licensed under the [MIT](LICENSE) license.