xref: /openbmc/linux/rust/macros/lib.rs (revision ff62b8e6)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 //! Crate for all kernel procedural macros.
4 
5 mod helpers;
6 mod module;
7 
8 use proc_macro::TokenStream;
9 
10 /// Declares a kernel module.
11 ///
12 /// The `type` argument should be a type which implements the [`Module`]
13 /// trait. Also accepts various forms of kernel metadata.
14 ///
15 /// C header: [`include/linux/moduleparam.h`](../../../include/linux/moduleparam.h)
16 ///
17 /// [`Module`]: ../kernel/trait.Module.html
18 ///
19 /// # Examples
20 ///
21 /// ```ignore
22 /// use kernel::prelude::*;
23 ///
24 /// module!{
25 ///     type: MyModule,
26 ///     name: b"my_kernel_module",
27 ///     author: b"Rust for Linux Contributors",
28 ///     description: b"My very own kernel module!",
29 ///     license: b"GPL",
30 ///     params: {
31 ///        my_i32: i32 {
32 ///            default: 42,
33 ///            permissions: 0o000,
34 ///            description: b"Example of i32",
35 ///        },
36 ///        writeable_i32: i32 {
37 ///            default: 42,
38 ///            permissions: 0o644,
39 ///            description: b"Example of i32",
40 ///        },
41 ///    },
42 /// }
43 ///
44 /// struct MyModule;
45 ///
46 /// impl kernel::Module for MyModule {
47 ///     fn init() -> Result<Self> {
48 ///         // If the parameter is writeable, then the kparam lock must be
49 ///         // taken to read the parameter:
50 ///         {
51 ///             let lock = THIS_MODULE.kernel_param_lock();
52 ///             pr_info!("i32 param is:  {}\n", writeable_i32.read(&lock));
53 ///         }
54 ///         // If the parameter is read only, it can be read without locking
55 ///         // the kernel parameters:
56 ///         pr_info!("i32 param is:  {}\n", my_i32.read());
57 ///         Ok(Self)
58 ///     }
59 /// }
60 /// ```
61 ///
62 /// # Supported argument types
63 ///   - `type`: type which implements the [`Module`] trait (required).
64 ///   - `name`: byte array of the name of the kernel module (required).
65 ///   - `author`: byte array of the author of the kernel module.
66 ///   - `description`: byte array of the description of the kernel module.
67 ///   - `license`: byte array of the license of the kernel module (required).
68 ///   - `alias`: byte array of alias name of the kernel module.
69 #[proc_macro]
70 pub fn module(ts: TokenStream) -> TokenStream {
71     module::module(ts)
72 }
73