The bootloader crate provides simple functions to create bootable disk images from a kernel. The basic idea is to build your kernel first and then invoke a builder function that calls the disk image creation functions of the bootloader crate.
A good way to implement this is to move your kernel into a kernel subdirectory. Then you can create
a new os crate at the top level that defines a workspace. The root package has build-dependencies on the kernel artifact and on the bootloader crate. This allows you to create the bootable disk image in a cargo build script and launch the created image in QEMU in the main function.
Our basic example showcases this setup:
- Cargo.toml
- create a workspace & add kernel as member
- add kernel as build-dependency
- add ovmf-prebuilt for UEFI booting in QEMU
- .cargo/config.toml
- enable the unstable artifact-dependencies feature
- rust-toolchain.toml
- change the default toolchain to nightly to use experimental features
- build.rs
- create bios and uefi disk image
- src/main.rs
- launch the image using QEMU
Now you should be able to use cargo build to create a bootable disk image and cargo run bios and cargo run uefi to run it in QEMU. Your kernel is automatically recompiled when it changes. For more advanced usage, you can add command-line arguments to your main.rs to e.g. pass additional arguments to QEMU or to copy the disk images to some path to make it easier to find them (e.g. for copying them to an thumb drive).