Merge branch 'post-3.2' into post-3.3

.cargo/config.toml

@@ -0,0 +1,2 @@
+[unstable]
+bindeps = true

.github/workflows/code.yml

@@ -15,8 +15,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v3
-      - run: rustup target add x86_64-unknown-none
-      - run: cargo check --target x86_64-unknown-none
+      - run: cargo check
 
   test:
     name: Test
@@ -30,9 +29,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v3
-
-      - run: rustup target add x86_64-unknown-none
-      - run: cargo build --target x86_64-unknown-none
+      - run: cargo build
 
   fmt:
     name: Check Formatting
@@ -46,7 +43,4 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-
-      - run: rustup target add x86_64-unknown-none
-      - run: rustup component add clippy
-      - run: cargo clippy --target x86_64-unknown-none
+      - run: cargo clippy

Cargo.lock

@@ -1,7 +1,519 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
+
+[[package]]
+name = "anyhow"
+version = "1.0.77"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c9d19de80eff169429ac1e9f48fffb163916b448a44e8e046186232046d9e1f9"
+
+[[package]]
+name = "autocfg"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
+
+[[package]]
+name = "az"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7b7e4c2464d97fe331d41de9d5db0def0a96f4d823b8b32a2efd503578988973"
+
+[[package]]
+name = "bincode"
+version = "1.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f45e9417d87227c7a56d22e471c6206462cba514c7590c09aff4cf6d1ddcad"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "bitflags"
+version = "1.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "bitflags"
+version = "2.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "327762f6e5a765692301e5bb513e0d9fef63be86bbc14528052b1cd3e6f03e07"
+
+[[package]]
+name = "bitvec"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bc2832c24239b0141d5674bb9174f9d68a8b5b3f2753311927c172ca46f7e9c"
+dependencies = [
+ "funty",
+ "radium",
+ "tap",
+ "wyz",
+]
+
+[[package]]
+name = "blog_os"
+version = "0.1.0"
+dependencies = [
+ "bootloader",
+ "kernel",
+ "ovmf-prebuilt",
+]
+
+[[package]]
+name = "bootloader"
+version = "0.11.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "718ebb60a92a2e37f9c6c6ab26f0adfd117aa6f1a8cd08d07bbd5a7762ff0812"
+dependencies = [
+ "anyhow",
+ "bootloader-boot-config",
+ "fatfs",
+ "gpt",
+ "llvm-tools",
+ "mbrman",
+ "serde_json",
+ "tempfile",
+]
+
+[[package]]
+name = "bootloader-boot-config"
+version = "0.11.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a4ff46e7fd938aa06b17d44dce17f605105da3df01b1ae8a7f02d248c9b12f6"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "bootloader_api"
+version = "0.11.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77fadafc2a2fa690f4f14a2e2a41c65d9e810b7fe959245bdf6d3b9c6d7e4bf1"
+
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
+[[package]]
+name = "cfg-if"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
+
+[[package]]
+name = "crc"
+version = "3.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "86ec7a15cbe22e59248fc7eadb1907dab5ba09372595da4d73dd805ed4417dfe"
+dependencies = [
+ "crc-catalog",
+]
+
+[[package]]
+name = "crc-catalog"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19d374276b40fb8bbdee95aef7c7fa6b5316ec764510eb64b8dd0e2ed0d7e7f5"
+
+[[package]]
+name = "embedded-graphics"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0649998afacf6d575d126d83e68b78c0ab0e00ca2ac7e9b3db11b4cbe8274ef0"
+dependencies = [
+ "az",
+ "byteorder",
+ "embedded-graphics-core",
+ "float-cmp",
+ "micromath",
+]
+
+[[package]]
+name = "embedded-graphics-core"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba9ecd261f991856250d2207f6d8376946cd9f412a2165d3b75bc87a0bc7a044"
+dependencies = [
+ "az",
+ "byteorder",
+]
+
+[[package]]
+name = "errno"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a258e46cdc063eb8519c00b9fc845fc47bcfca4130e2f08e88665ceda8474245"
+dependencies = [
+ "libc",
+ "windows-sys",
+]
+
+[[package]]
+name = "fastrand"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25cbce373ec4653f1a01a31e8a5e5ec0c622dc27ff9c4e6606eefef5cbbed4a5"
+
+[[package]]
+name = "fatfs"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05669f8e7e2d7badc545c513710f0eba09c2fbef683eb859fd79c46c355048e0"
+dependencies = [
+ "bitflags 1.3.2",
+ "byteorder",
+ "log",
+]
+
+[[package]]
+name = "float-cmp"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "98de4bbd547a563b716d8dfa9aad1cb19bfab00f4fa09a6a4ed21dbcf44ce9c4"
+dependencies = [
+ "num-traits",
+]
+
+[[package]]
+name = "funty"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
+
+[[package]]
+name = "getrandom"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe9006bed769170c11f845cf00c7c1e9092aeb3f268e007c3e760ac68008070f"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi",
+]
+
+[[package]]
+name = "gpt"
+version = "3.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8283e7331b8c93b9756e0cfdbcfb90312852f953c6faf9bf741e684cc3b6ad69"
+dependencies = [
+ "bitflags 2.4.1",
+ "crc",
+ "log",
+ "uuid",
+]
+
+[[package]]
+name = "itoa"
+version = "1.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1a46d1a171d865aa5f83f92695765caa047a9b4cbae2cbf37dbd613a793fd4c"
 
 [[package]]
 name = "kernel"
 version = "0.1.0"
+dependencies = [
+ "bootloader_api",
+ "embedded-graphics",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.151"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "302d7ab3130588088d277783b1e2d2e10c9e9e4a16dd9050e6ec93fb3e7048f4"
+
+[[package]]
+name = "linux-raw-sys"
+version = "0.4.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c4cd1a83af159aa67994778be9070f0ae1bd732942279cabb14f86f986a21456"
+
+[[package]]
+name = "llvm-tools"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "955be5d0ca0465caf127165acb47964f911e2bc26073e865deb8be7189302faf"
+
+[[package]]
+name = "log"
+version = "0.4.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"
+
+[[package]]
+name = "mbrman"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c487024623ae38584610237dd1be8932bb2b324474b23c37a25f9fbe6bf5e9e"
+dependencies = [
+ "bincode",
+ "bitvec",
+ "serde",
+ "serde-big-array",
+ "thiserror",
+]
+
+[[package]]
+name = "micromath"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3c8dda44ff03a2f238717214da50f65d5a53b45cd213a7370424ffdb6fae815"
+
+[[package]]
+name = "num-traits"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "39e3200413f237f41ab11ad6d161bc7239c84dcb631773ccd7de3dfe4b5c267c"
+dependencies = [
+ "autocfg",
+]
+
+[[package]]
+name = "ovmf-prebuilt"
+version = "0.1.0-alpha.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa50141d081512ab30fd9e7e7692476866df5098b028536ad6680212e717fa8d"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.71"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "75cb1540fadbd5b8fbccc4dddad2734eba435053f725621c070711a14bb5f4b8"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5267fca4496028628a95160fc423a33e8b2e6af8a5302579e322e4b520293cae"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "radium"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc33ff2d4973d518d823d61aa239014831e521c75da58e3df4840d3f47749d09"
+
+[[package]]
+name = "redox_syscall"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4722d768eff46b75989dd134e5c353f0d6296e5aaa3132e776cbdb56be7731aa"
+dependencies = [
+ "bitflags 1.3.2",
+]
+
+[[package]]
+name = "rustix"
+version = "0.38.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72e572a5e8ca657d7366229cdde4bd14c4eb5499a9573d4d366fe1b599daa316"
+dependencies = [
+ "bitflags 2.4.1",
+ "errno",
+ "libc",
+ "linux-raw-sys",
+ "windows-sys",
+]
+
+[[package]]
+name = "ryu"
+version = "1.0.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f98d2aa92eebf49b69786be48e4477826b256916e84a57ff2a4f21923b48eb4c"
+
+[[package]]
+name = "serde"
+version = "1.0.193"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25dd9975e68d0cb5aa1120c288333fc98731bd1dd12f561e468ea4728c042b89"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde-big-array"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3323f09a748af288c3dc2474ea6803ee81f118321775bffa3ac8f7e65c5e90e7"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.193"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43576ca501357b9b071ac53cdc7da8ef0cbd9493d8df094cd821777ea6e894d3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "serde_json"
+version = "1.0.108"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d1c7e3eac408d115102c4c24ad393e0821bb3a5df4d506a80f85f7a742a526b"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
+[[package]]
+name = "syn"
+version = "2.0.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee659fb5f3d355364e1f3e5bc10fb82068efbf824a1e9d1c9504244a6469ad53"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "tap"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
+
+[[package]]
+name = "tempfile"
+version = "3.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "01ce4141aa927a6d1bd34a041795abd0db1cccba5d5f24b009f694bdf3a1f3fa"
+dependencies = [
+ "cfg-if",
+ "fastrand",
+ "redox_syscall",
+ "rustix",
+ "windows-sys",
+]
+
+[[package]]
+name = "thiserror"
+version = "1.0.52"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "83a48fd946b02c0a526b2e9481c8e2a17755e47039164a86c4070446e3a4614d"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.52"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e7fbe9b594d6568a6a1443250a7e67d80b74e1e96f6d1715e1e21cc1888291d3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
+
+[[package]]
+name = "uuid"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e395fcf16a7a3d8127ec99782007af141946b4795001f876d54fb0d55978560"
+dependencies = [
+ "getrandom",
+]
+
+[[package]]
+name = "wasi"
+version = "0.11.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
+
+[[package]]
+name = "windows-sys"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "282be5f36a8ce781fad8c8ae18fa3f9beff57ec1b52cb3de0789201425d9a33d"
+dependencies = [
+ "windows-targets",
+]
+
+[[package]]
+name = "windows-targets"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a18201040b24831fbb9e4eb208f8892e1f50a37feb53cc7ff887feb8f50e7cd"
+dependencies = [
+ "windows_aarch64_gnullvm",
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_gnullvm",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_gnullvm"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb7764e35d4db8a7921e09562a0304bf2f93e0a51bfccee0bd0bb0b666b015ea"
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbaa0368d4f1d2aaefc55b6fcfee13f41544ddf36801e793edbbfd7d7df075ef"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a28637cb1fa3560a16915793afb20081aba2c92ee8af57b4d5f28e4b3e7df313"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ffe5e8e31046ce6230cc7215707b816e339ff4d4d67c65dffa206fd0f7aa7b9a"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3d6fa32db2bc4a2f5abeacf2b69f7992cd09dca97498da74a151a3132c26befd"
+
+[[package]]
+name = "windows_x86_64_gnullvm"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a657e1e9d3f514745a572a6846d3c7aa7dbe1658c056ed9c3344c4109a6949e"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dff9641d1cd4be8d1a070daf9e3773c5f67e78b4d9d42263020c057706765c04"
+
+[[package]]
+name = "wyz"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05f360fc0b24296329c78fda852a1e9ae82de9cf7b27dae4b7f62f118f77b9ed"
+dependencies = [
+ "tap",
+]

Cargo.toml

@@ -1,8 +1,15 @@
 [package]
-name = "kernel"
+name = "blog_os"
 version = "0.1.0"
 edition = "2021"
+default-run = "blog_os"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[workspace]
+members = ["kernel"]
 
 [dependencies]
+ovmf-prebuilt = "0.1.0-alpha"
+
+[build-dependencies]
+kernel = { path = "kernel", artifact = "bin", target = "x86_64-unknown-none" }
+bootloader = "0.11.3"

README.md

@@ -1,23 +1,16 @@
-# Blog OS (Minimal Kernel)
+# Blog OS (Booting)
 
-[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-3.1)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-3.1)
+[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-3.2)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-3.2)
 
-This repository contains the source code for the [Minimal Kernel][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.
+This repository contains the source code for the [Booting][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.
 
-[post]: https://os.phil-opp.com/minimal-kernel
+[post]: https://os.phil-opp.com/booting
 
 **Check out the [master branch](https://github.com/phil-opp/blog_os) for more information.**
 
 ## Building
 
-- Install the `x86_64-unknown-none` target using rustup:
-  ```
-  rustup target add x86_64-unknown-none
-  ```
-- Build by running:
-  ```
-  cargo build --target x86_64-unknown-none
-  ```
+TODO
 
 ## License
 

build.rs

@@ -0,0 +1,21 @@
+use bootloader::DiskImageBuilder;
+use std::{env, path::PathBuf};
+
+fn main() {
+    // set by cargo for the kernel artifact dependency
+    let kernel_path = env::var("CARGO_BIN_FILE_KERNEL").unwrap();
+    let disk_builder = DiskImageBuilder::new(PathBuf::from(kernel_path));
+
+    // specify output paths
+    let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
+    let uefi_path = out_dir.join("blog_os-uefi.img");
+    let bios_path = out_dir.join("blog_os-bios.img");
+
+    // create the disk images
+    disk_builder.create_uefi_image(&uefi_path).unwrap();
+    disk_builder.create_bios_image(&bios_path).unwrap();
+
+    // pass the disk image paths via environment variables
+    println!("cargo:rustc-env=UEFI_IMAGE={}", uefi_path.display());
+    println!("cargo:rustc-env=BIOS_IMAGE={}", bios_path.display());
+}

kernel/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "kernel"
+version = "0.1.0"
+edition = "2021"
+
+[[bin]]
+name = "kernel"
+test = false
+bench = false
+
+[dependencies]
+bootloader_api = "0.11.0"
+embedded-graphics = "0.8.1"

kernel/src/framebuffer.rs

@@ -0,0 +1,138 @@
+use bootloader_api::info::{FrameBuffer, FrameBufferInfo, PixelFormat};
+use embedded_graphics::{
+    draw_target::DrawTarget,
+    geometry::{self, Point},
+    pixelcolor::{Rgb888, RgbColor},
+    Pixel,
+};
+
+pub struct Display {
+    framebuffer: &'static mut [u8],
+    info: FrameBufferInfo,
+}
+
+impl Display {
+    pub fn new(framebuffer: &'static mut FrameBuffer) -> Display {
+        Self {
+            info: framebuffer.info(),
+            framebuffer: framebuffer.buffer_mut(),
+        }
+    }
+
+    fn draw_pixel(&mut self, coordinates: Point, color: Rgb888) {
+        // ignore any pixels that are out of bounds.
+        let position = match (coordinates.x.try_into(), coordinates.y.try_into()) {
+            (Ok(x), Ok(y)) if x < self.info.width && y < self.info.height => Position { x, y },
+            _ => return, // ignore out-of-bounds pixel
+        };
+        let color = Color {
+            red: color.r(),
+            green: color.g(),
+            blue: color.b(),
+        };
+        set_pixel_in(self.framebuffer, self.info, position, color);
+    }
+
+    pub fn split_at_line(self, line_index: usize) -> (Self, Self) {
+        assert!(line_index < self.info.height);
+
+        let byte_offset = line_index * self.info.stride * self.info.bytes_per_pixel;
+        let (first_buffer, second_buffer) = self.framebuffer.split_at_mut(byte_offset);
+
+        let first = Self {
+            framebuffer: first_buffer,
+            info: FrameBufferInfo {
+                byte_len: byte_offset,
+                height: line_index,
+                ..self.info
+            },
+        };
+        let second = Self {
+            framebuffer: second_buffer,
+            info: FrameBufferInfo {
+                byte_len: self.info.byte_len - byte_offset,
+                height: self.info.height - line_index,
+                ..self.info
+            },
+        };
+
+        (first, second)
+    }
+}
+
+impl DrawTarget for Display {
+    type Color = Rgb888;
+
+    /// Drawing operations can never fail.
+    type Error = core::convert::Infallible;
+
+    fn draw_iter<I>(&mut self, pixels: I) -> Result<(), Self::Error>
+    where
+        I: IntoIterator<Item = Pixel<Self::Color>>,
+    {
+        for Pixel(coordinates, color) in pixels.into_iter() {
+            self.draw_pixel(coordinates, color);
+        }
+        Ok(())
+    }
+}
+
+impl geometry::OriginDimensions for Display {
+    fn size(&self) -> geometry::Size {
+        geometry::Size::new(
+            self.info.width.try_into().unwrap(),
+            self.info.height.try_into().unwrap(),
+        )
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Position {
+    pub x: usize,
+    pub y: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Color {
+    pub red: u8,
+    pub green: u8,
+    pub blue: u8,
+}
+
+pub fn set_pixel_in(
+    framebuffer: &mut [u8],
+    info: FrameBufferInfo,
+    position: Position,
+    color: Color,
+) {
+    // calculate offset to first byte of pixel
+    let byte_offset = {
+        // use stride to calculate pixel offset of target line
+        let line_offset = position.y * info.stride;
+        // add x position to get the absolute pixel offset in buffer
+        let pixel_offset = line_offset + position.x;
+        // convert to byte offset
+        pixel_offset * info.bytes_per_pixel
+    };
+
+    // set pixel based on color format
+    let pixel_bytes = &mut framebuffer[byte_offset..];
+    match info.pixel_format {
+        PixelFormat::Rgb => {
+            pixel_bytes[0] = color.red;
+            pixel_bytes[1] = color.green;
+            pixel_bytes[2] = color.blue;
+        }
+        PixelFormat::Bgr => {
+            pixel_bytes[0] = color.blue;
+            pixel_bytes[1] = color.green;
+            pixel_bytes[2] = color.red;
+        }
+        PixelFormat::U8 => {
+            // use a simple average-based grayscale transform
+            let gray = color.red / 3 + color.green / 3 + color.blue / 3;
+            pixel_bytes[0] = gray;
+        }
+        other => panic!("unknown pixel format {other:?}"),
+    }
+}

kernel/src/main.rs

@@ -0,0 +1,50 @@
+#![no_std]
+#![no_main]
+
+use core::{convert::Infallible, panic::PanicInfo};
+
+use bootloader_api::BootInfo;
+use embedded_graphics::{
+    draw_target::DrawTarget,
+    geometry::Point,
+    mono_font::{ascii::FONT_10X20, MonoTextStyle},
+    pixelcolor::{Rgb888, RgbColor},
+    primitives::{Circle, PrimitiveStyle, StyledDrawable},
+    text::Text,
+    Drawable,
+};
+
+mod framebuffer;
+
+bootloader_api::entry_point!(kernel_main);
+
+fn kernel_main(boot_info: &'static mut BootInfo) -> ! {
+    if let Some(framebuffer) = boot_info.framebuffer.as_mut() {
+        let height = framebuffer.info().height;
+        let display = framebuffer::Display::new(framebuffer);
+        let (mut upper, mut lower) = display.split_at_line(height / 2);
+
+        upper.clear(Rgb888::RED).unwrap_or_else(infallible);
+        lower.clear(Rgb888::BLUE).unwrap_or_else(infallible);
+
+        let style = PrimitiveStyle::with_fill(Rgb888::YELLOW);
+        Circle::new(Point::new(50, 50), 300)
+            .draw_styled(&style, &mut upper)
+            .unwrap_or_else(infallible);
+
+        let character_style = MonoTextStyle::new(&FONT_10X20, Rgb888::BLUE);
+        let text = Text::new("Hello, world!", Point::new(140, 210), character_style);
+        text.draw(&mut upper).unwrap_or_else(infallible);
+    }
+    loop {}
+}
+
+/// This function is called on panic.
+#[panic_handler]
+fn panic(_info: &PanicInfo) -> ! {
+    loop {}
+}
+
+fn infallible<T>(v: Infallible) -> T {
+    match v {}
+}

rust-toolchain.toml

@@ -0,0 +1,5 @@
+[toolchain]
+channel = "nightly"
+profile = "default"
+targets = ["x86_64-unknown-none"]
+components = ["rust-src", "llvm-tools-preview"]

src/bin/qemu-bios.rs

@@ -0,0 +1,12 @@
+use std::{
+    env,
+    process::{self, Command},
+};
+
+fn main() {
+    let mut qemu = Command::new("qemu-system-x86_64");
+    qemu.arg("-drive");
+    qemu.arg(format!("format=raw,file={}", env!("BIOS_IMAGE")));
+    let exit_status = qemu.status().unwrap();
+    process::exit(exit_status.code().unwrap_or(-1));
+}

src/bin/qemu-uefi.rs

@@ -0,0 +1,13 @@
+use std::{
+    env,
+    process::{self, Command},
+};
+
+fn main() {
+    let mut qemu = Command::new("qemu-system-x86_64");
+    qemu.arg("-drive");
+    qemu.arg(format!("format=raw,file={}", env!("UEFI_IMAGE")));
+    qemu.arg("-bios").arg(ovmf_prebuilt::ovmf_pure_efi());
+    let exit_status = qemu.status().unwrap();
+    process::exit(exit_status.code().unwrap_or(-1));
+}

src/main.rs

@@ -1,15 +1,13 @@
-#![no_std]
-#![no_main]
+use std::{env, fs};
 
-use core::panic::PanicInfo;
+fn main() {
+    let current_exe = env::current_exe().unwrap();
+    let uefi_target = current_exe.with_file_name("uefi.img");
+    let bios_target = current_exe.with_file_name("bios.img");
 
-#[no_mangle]
-pub extern "C" fn _start() -> ! {
-    loop {}
-}
-
-/// This function is called on panic.
-#[panic_handler]
-fn panic(_info: &PanicInfo) -> ! {
-    loop {}
+    fs::copy(env!("UEFI_IMAGE"), &uefi_target).unwrap();
+    fs::copy(env!("BIOS_IMAGE"), &bios_target).unwrap();
+
+    println!("UEFI disk image at {}", uefi_target.display());
+    println!("BIOS disk image at {}", bios_target.display());
 }