1 files changed, 78 insertions, 0 deletions
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
new file mode 100644
index 000000000000..abd46261d385
--- /dev/null
+++ b/rust/kernel/lib.rs
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! The `kernel` crate.
+//!
+//! This crate contains the kernel APIs that have been ported or wrapped for
+//! usage by Rust code in the kernel and is shared by all of them.
+//!
+//! In other words, all the rest of the Rust code in the kernel (e.g. kernel
+//! modules written in Rust) depends on [`core`], [`alloc`] and this crate.
+//!
+//! If you need a kernel C API that is not ported or wrapped yet here, then
+//! do so first instead of bypassing this crate.
+
+#![no_std]
+#![feature(core_ffi_c)]
+
+// Ensure conditional compilation based on the kernel configuration works;
+// otherwise we may silently break things like initcall handling.
+#[cfg(not(CONFIG_RUST))]
+compile_error!("Missing kernel configuration for conditional compilation");
+
+#[cfg(not(test))]
+#[cfg(not(testlib))]
+mod allocator;
+pub mod error;
+pub mod prelude;
+pub mod print;
+pub mod str;
+
+#[doc(hidden)]
+pub use bindings;
+pub use macros;
+
+/// Prefix to appear before log messages printed from within the `kernel` crate.
+const __LOG_PREFIX: &[u8] = b"rust_kernel\0";
+
+/// The top level entrypoint to implementing a kernel module.
+///
+/// For any teardown or cleanup operations, your type may implement [`Drop`].
+pub trait Module: Sized + Sync {
+    /// Called at module initialization time.
+    ///
+    /// Use this method to perform whatever setup or registration your module
+    /// should do.
+    ///
+    /// Equivalent to the `module_init` macro in the C API.
+    fn init(module: &'static ThisModule) -> error::Result<Self>;
+}
+
+/// Equivalent to `THIS_MODULE` in the C API.
+///
+/// C header: `include/linux/export.h`
+pub struct ThisModule(*mut bindings::module);
+
+// SAFETY: `THIS_MODULE` may be used from all threads within a module.
+unsafe impl Sync for ThisModule {}
+
+impl ThisModule {
+    /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer.
+    ///
+    /// # Safety
+    ///
+    /// The pointer must be equal to the right `THIS_MODULE`.
+    pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule {
+        ThisModule(ptr)
+    }
+}
+
+#[cfg(not(any(testlib, test)))]
+#[panic_handler]
+fn panic(info: &core::panic::PanicInfo<'_>) -> ! {
+    pr_emerg!("{}\n", info);
+    // SAFETY: FFI call.
+    unsafe { bindings::BUG() };
+    // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()`
+    // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>.
+    loop {}
+}