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(explicit_generic_args_with_impl_trait)] 20 #![feature(generic_associated_types)] 21 #![feature(new_uninit)] 22 #![feature(pin_macro)] 23 #![feature(receiver_trait)] 24 #![feature(unsize)] 25 26 // Ensure conditional compilation based on the kernel configuration works; 27 // otherwise we may silently break things like initcall handling. 28 #[cfg(not(CONFIG_RUST))] 29 compile_error!("Missing kernel configuration for conditional compilation"); 30 31 // Allow proc-macros to refer to `::kernel` inside the `kernel` crate (this crate). 32 extern crate self as kernel; 33 34 #[cfg(not(test))] 35 #[cfg(not(testlib))] 36 mod allocator; 37 mod build_assert; 38 pub mod error; 39 pub mod init; 40 pub mod prelude; 41 pub mod print; 42 mod static_assert; 43 #[doc(hidden)] 44 pub mod std_vendor; 45 pub mod str; 46 pub mod sync; 47 pub mod types; 48 49 #[doc(hidden)] 50 pub use bindings; 51 pub use macros; 52 53 #[doc(hidden)] 54 pub use build_error::build_error; 55 56 /// Prefix to appear before log messages printed from within the `kernel` crate. 57 const __LOG_PREFIX: &[u8] = b"rust_kernel\0"; 58 59 /// The top level entrypoint to implementing a kernel module. 60 /// 61 /// For any teardown or cleanup operations, your type may implement [`Drop`]. 62 pub trait Module: Sized + Sync { 63 /// Called at module initialization time. 64 /// 65 /// Use this method to perform whatever setup or registration your module 66 /// should do. 67 /// 68 /// Equivalent to the `module_init` macro in the C API. 69 fn init(module: &'static ThisModule) -> error::Result<Self>; 70 } 71 72 /// Equivalent to `THIS_MODULE` in the C API. 73 /// 74 /// C header: `include/linux/export.h` 75 pub struct ThisModule(*mut bindings::module); 76 77 // SAFETY: `THIS_MODULE` may be used from all threads within a module. 78 unsafe impl Sync for ThisModule {} 79 80 impl ThisModule { 81 /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer. 82 /// 83 /// # Safety 84 /// 85 /// The pointer must be equal to the right `THIS_MODULE`. 86 pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule { 87 ThisModule(ptr) 88 } 89 } 90 91 #[cfg(not(any(testlib, test)))] 92 #[panic_handler] 93 fn panic(info: &core::panic::PanicInfo<'_>) -> ! { 94 pr_emerg!("{}\n", info); 95 // SAFETY: FFI call. 96 unsafe { bindings::BUG() }; 97 // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()` 98 // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>. 99 loop {} 100 } 101