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(new_uninit)] 21 #![feature(receiver_trait)] 22 #![feature(unsize)] 23 24 // Ensure conditional compilation based on the kernel configuration works; 25 // otherwise we may silently break things like initcall handling. 26 #[cfg(not(CONFIG_RUST))] 27 compile_error!("Missing kernel configuration for conditional compilation"); 28 29 #[cfg(not(test))] 30 #[cfg(not(testlib))] 31 mod allocator; 32 mod build_assert; 33 pub mod error; 34 pub mod prelude; 35 pub mod print; 36 mod static_assert; 37 #[doc(hidden)] 38 pub mod std_vendor; 39 pub mod str; 40 pub mod sync; 41 pub mod types; 42 43 #[doc(hidden)] 44 pub use bindings; 45 pub use macros; 46 47 #[doc(hidden)] 48 pub use build_error::build_error; 49 50 /// Prefix to appear before log messages printed from within the `kernel` crate. 51 const __LOG_PREFIX: &[u8] = b"rust_kernel\0"; 52 53 /// The top level entrypoint to implementing a kernel module. 54 /// 55 /// For any teardown or cleanup operations, your type may implement [`Drop`]. 56 pub trait Module: Sized + Sync { 57 /// Called at module initialization time. 58 /// 59 /// Use this method to perform whatever setup or registration your module 60 /// should do. 61 /// 62 /// Equivalent to the `module_init` macro in the C API. 63 fn init(module: &'static ThisModule) -> error::Result<Self>; 64 } 65 66 /// Equivalent to `THIS_MODULE` in the C API. 67 /// 68 /// C header: `include/linux/export.h` 69 pub struct ThisModule(*mut bindings::module); 70 71 // SAFETY: `THIS_MODULE` may be used from all threads within a module. 72 unsafe impl Sync for ThisModule {} 73 74 impl ThisModule { 75 /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer. 76 /// 77 /// # Safety 78 /// 79 /// The pointer must be equal to the right `THIS_MODULE`. 80 pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule { 81 ThisModule(ptr) 82 } 83 } 84 85 #[cfg(not(any(testlib, test)))] 86 #[panic_handler] 87 fn panic(info: &core::panic::PanicInfo<'_>) -> ! { 88 pr_emerg!("{}\n", info); 89 // SAFETY: FFI call. 90 unsafe { bindings::BUG() }; 91 // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()` 92 // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>. 93 loop {} 94 } 95