1 // SPDX-License-Identifier: GPL-2.0 2 3 //! The `kernel` crate. 4 //! 5 //! This crate contains the kernel APIs that have been ported or wrapped for 6 //! usage by Rust code in the kernel and is shared by all of them. 7 //! 8 //! In other words, all the rest of the Rust code in the kernel (e.g. kernel 9 //! modules written in Rust) depends on [`core`], [`alloc`] and this crate. 10 //! 11 //! If you need a kernel C API that is not ported or wrapped yet here, then 12 //! do so first instead of bypassing this crate. 13 14 #![no_std] 15 #![feature(allocator_api)] 16 #![feature(coerce_unsized)] 17 #![feature(core_ffi_c)] 18 #![feature(dispatch_from_dyn)] 19 #![feature(generic_associated_types)] 20 #![feature(receiver_trait)] 21 #![feature(unsize)] 22 23 // Ensure conditional compilation based on the kernel configuration works; 24 // otherwise we may silently break things like initcall handling. 25 #[cfg(not(CONFIG_RUST))] 26 compile_error!("Missing kernel configuration for conditional compilation"); 27 28 #[cfg(not(test))] 29 #[cfg(not(testlib))] 30 mod allocator; 31 mod build_assert; 32 pub mod error; 33 pub mod prelude; 34 pub mod print; 35 mod static_assert; 36 #[doc(hidden)] 37 pub mod std_vendor; 38 pub mod str; 39 pub mod sync; 40 pub mod types; 41 42 #[doc(hidden)] 43 pub use bindings; 44 pub use macros; 45 46 #[doc(hidden)] 47 pub use build_error::build_error; 48 49 /// Prefix to appear before log messages printed from within the `kernel` crate. 50 const __LOG_PREFIX: &[u8] = b"rust_kernel\0"; 51 52 /// The top level entrypoint to implementing a kernel module. 53 /// 54 /// For any teardown or cleanup operations, your type may implement [`Drop`]. 55 pub trait Module: Sized + Sync { 56 /// Called at module initialization time. 57 /// 58 /// Use this method to perform whatever setup or registration your module 59 /// should do. 60 /// 61 /// Equivalent to the `module_init` macro in the C API. 62 fn init(module: &'static ThisModule) -> error::Result<Self>; 63 } 64 65 /// Equivalent to `THIS_MODULE` in the C API. 66 /// 67 /// C header: `include/linux/export.h` 68 pub struct ThisModule(*mut bindings::module); 69 70 // SAFETY: `THIS_MODULE` may be used from all threads within a module. 71 unsafe impl Sync for ThisModule {} 72 73 impl ThisModule { 74 /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer. 75 /// 76 /// # Safety 77 /// 78 /// The pointer must be equal to the right `THIS_MODULE`. 79 pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule { 80 ThisModule(ptr) 81 } 82 } 83 84 #[cfg(not(any(testlib, test)))] 85 #[panic_handler] 86 fn panic(info: &core::panic::PanicInfo<'_>) -> ! { 87 pr_emerg!("{}\n", info); 88 // SAFETY: FFI call. 89 unsafe { bindings::BUG() }; 90 // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()` 91 // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>. 92 loop {} 93 } 94