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 ioctl; 41 pub mod prelude; 42 pub mod print; 43 mod static_assert; 44 #[doc(hidden)] 45 pub mod std_vendor; 46 pub mod str; 47 pub mod sync; 48 pub mod task; 49 pub mod types; 50 51 #[doc(hidden)] 52 pub use bindings; 53 pub use macros; 54 pub use uapi; 55 56 #[doc(hidden)] 57 pub use build_error::build_error; 58 59 /// Prefix to appear before log messages printed from within the `kernel` crate. 60 const __LOG_PREFIX: &[u8] = b"rust_kernel\0"; 61 62 /// The top level entrypoint to implementing a kernel module. 63 /// 64 /// For any teardown or cleanup operations, your type may implement [`Drop`]. 65 pub trait Module: Sized + Sync { 66 /// Called at module initialization time. 67 /// 68 /// Use this method to perform whatever setup or registration your module 69 /// should do. 70 /// 71 /// Equivalent to the `module_init` macro in the C API. 72 fn init(module: &'static ThisModule) -> error::Result<Self>; 73 } 74 75 /// Equivalent to `THIS_MODULE` in the C API. 76 /// 77 /// C header: `include/linux/export.h` 78 pub struct ThisModule(*mut bindings::module); 79 80 // SAFETY: `THIS_MODULE` may be used from all threads within a module. 81 unsafe impl Sync for ThisModule {} 82 83 impl ThisModule { 84 /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer. 85 /// 86 /// # Safety 87 /// 88 /// The pointer must be equal to the right `THIS_MODULE`. 89 pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule { 90 ThisModule(ptr) 91 } 92 } 93 94 #[cfg(not(any(testlib, test)))] 95 #[panic_handler] 96 fn panic(info: &core::panic::PanicInfo<'_>) -> ! { 97 pr_emerg!("{}\n", info); 98 // SAFETY: FFI call. 99 unsafe { bindings::BUG() }; 100 // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()` 101 // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>. 102 loop {} 103 } 104