| // SPDX-License-Identifier: GPL-2.0 |
| |
| use crate::helpers::*; |
| use proc_macro::{token_stream, Delimiter, Literal, TokenStream, TokenTree}; |
| use std::fmt::Write; |
| |
| fn expect_string_array(it: &mut token_stream::IntoIter) -> Vec<String> { |
| let group = expect_group(it); |
| assert_eq!(group.delimiter(), Delimiter::Bracket); |
| let mut values = Vec::new(); |
| let mut it = group.stream().into_iter(); |
| |
| while let Some(val) = try_string(&mut it) { |
| assert!(val.is_ascii(), "Expected ASCII string"); |
| values.push(val); |
| match it.next() { |
| Some(TokenTree::Punct(punct)) => assert_eq!(punct.as_char(), ','), |
| None => break, |
| _ => panic!("Expected ',' or end of array"), |
| } |
| } |
| values |
| } |
| |
| struct ModInfoBuilder<'a> { |
| module: &'a str, |
| counter: usize, |
| buffer: String, |
| } |
| |
| impl<'a> ModInfoBuilder<'a> { |
| fn new(module: &'a str) -> Self { |
| ModInfoBuilder { |
| module, |
| counter: 0, |
| buffer: String::new(), |
| } |
| } |
| |
| fn emit_base(&mut self, field: &str, content: &str, builtin: bool) { |
| let string = if builtin { |
| // Built-in modules prefix their modinfo strings by `module.`. |
| format!( |
| "{module}.{field}={content}\0", |
| module = self.module, |
| field = field, |
| content = content |
| ) |
| } else { |
| // Loadable modules' modinfo strings go as-is. |
| format!("{field}={content}\0", field = field, content = content) |
| }; |
| |
| write!( |
| &mut self.buffer, |
| " |
| {cfg} |
| #[doc(hidden)] |
| #[link_section = \".modinfo\"] |
| #[used] |
| pub static __{module}_{counter}: [u8; {length}] = *{string}; |
| ", |
| cfg = if builtin { |
| "#[cfg(not(MODULE))]" |
| } else { |
| "#[cfg(MODULE)]" |
| }, |
| module = self.module.to_uppercase(), |
| counter = self.counter, |
| length = string.len(), |
| string = Literal::byte_string(string.as_bytes()), |
| ) |
| .unwrap(); |
| |
| self.counter += 1; |
| } |
| |
| fn emit_only_builtin(&mut self, field: &str, content: &str) { |
| self.emit_base(field, content, true) |
| } |
| |
| fn emit_only_loadable(&mut self, field: &str, content: &str) { |
| self.emit_base(field, content, false) |
| } |
| |
| fn emit(&mut self, field: &str, content: &str) { |
| self.emit_only_builtin(field, content); |
| self.emit_only_loadable(field, content); |
| } |
| } |
| |
| #[derive(Debug, Default)] |
| struct ModuleInfo { |
| type_: String, |
| license: String, |
| name: String, |
| author: Option<String>, |
| description: Option<String>, |
| alias: Option<Vec<String>>, |
| } |
| |
| impl ModuleInfo { |
| fn parse(it: &mut token_stream::IntoIter) -> Self { |
| let mut info = ModuleInfo::default(); |
| |
| const EXPECTED_KEYS: &[&str] = |
| &["type", "name", "author", "description", "license", "alias"]; |
| const REQUIRED_KEYS: &[&str] = &["type", "name", "license"]; |
| let mut seen_keys = Vec::new(); |
| |
| loop { |
| let key = match it.next() { |
| Some(TokenTree::Ident(ident)) => ident.to_string(), |
| Some(_) => panic!("Expected Ident or end"), |
| None => break, |
| }; |
| |
| if seen_keys.contains(&key) { |
| panic!( |
| "Duplicated key \"{}\". Keys can only be specified once.", |
| key |
| ); |
| } |
| |
| assert_eq!(expect_punct(it), ':'); |
| |
| match key.as_str() { |
| "type" => info.type_ = expect_ident(it), |
| "name" => info.name = expect_string_ascii(it), |
| "author" => info.author = Some(expect_string(it)), |
| "description" => info.description = Some(expect_string(it)), |
| "license" => info.license = expect_string_ascii(it), |
| "alias" => info.alias = Some(expect_string_array(it)), |
| _ => panic!( |
| "Unknown key \"{}\". Valid keys are: {:?}.", |
| key, EXPECTED_KEYS |
| ), |
| } |
| |
| assert_eq!(expect_punct(it), ','); |
| |
| seen_keys.push(key); |
| } |
| |
| expect_end(it); |
| |
| for key in REQUIRED_KEYS { |
| if !seen_keys.iter().any(|e| e == key) { |
| panic!("Missing required key \"{}\".", key); |
| } |
| } |
| |
| let mut ordered_keys: Vec<&str> = Vec::new(); |
| for key in EXPECTED_KEYS { |
| if seen_keys.iter().any(|e| e == key) { |
| ordered_keys.push(key); |
| } |
| } |
| |
| if seen_keys != ordered_keys { |
| panic!( |
| "Keys are not ordered as expected. Order them like: {:?}.", |
| ordered_keys |
| ); |
| } |
| |
| info |
| } |
| } |
| |
| pub(crate) fn module(ts: TokenStream) -> TokenStream { |
| let mut it = ts.into_iter(); |
| |
| let info = ModuleInfo::parse(&mut it); |
| |
| let mut modinfo = ModInfoBuilder::new(info.name.as_ref()); |
| if let Some(author) = info.author { |
| modinfo.emit("author", &author); |
| } |
| if let Some(description) = info.description { |
| modinfo.emit("description", &description); |
| } |
| modinfo.emit("license", &info.license); |
| if let Some(aliases) = info.alias { |
| for alias in aliases { |
| modinfo.emit("alias", &alias); |
| } |
| } |
| |
| // Built-in modules also export the `file` modinfo string. |
| let file = |
| std::env::var("RUST_MODFILE").expect("Unable to fetch RUST_MODFILE environmental variable"); |
| modinfo.emit_only_builtin("file", &file); |
| |
| format!( |
| " |
| /// The module name. |
| /// |
| /// Used by the printing macros, e.g. [`info!`]. |
| const __LOG_PREFIX: &[u8] = b\"{name}\\0\"; |
| |
| // SAFETY: `__this_module` is constructed by the kernel at load time and will not be |
| // freed until the module is unloaded. |
| #[cfg(MODULE)] |
| static THIS_MODULE: kernel::ThisModule = unsafe {{ |
| kernel::ThisModule::from_ptr(&kernel::bindings::__this_module as *const _ as *mut _) |
| }}; |
| #[cfg(not(MODULE))] |
| static THIS_MODULE: kernel::ThisModule = unsafe {{ |
| kernel::ThisModule::from_ptr(core::ptr::null_mut()) |
| }}; |
| |
| // Double nested modules, since then nobody can access the public items inside. |
| mod __module_init {{ |
| mod __module_init {{ |
| use super::super::{type_}; |
| |
| /// The \"Rust loadable module\" mark. |
| // |
| // This may be best done another way later on, e.g. as a new modinfo |
| // key or a new section. For the moment, keep it simple. |
| #[cfg(MODULE)] |
| #[doc(hidden)] |
| #[used] |
| static __IS_RUST_MODULE: () = (); |
| |
| static mut __MOD: Option<{type_}> = None; |
| |
| // Loadable modules need to export the `{{init,cleanup}}_module` identifiers. |
| /// # Safety |
| /// |
| /// This function must not be called after module initialization, because it may be |
| /// freed after that completes. |
| #[cfg(MODULE)] |
| #[doc(hidden)] |
| #[no_mangle] |
| #[link_section = \".init.text\"] |
| pub unsafe extern \"C\" fn init_module() -> core::ffi::c_int {{ |
| // SAFETY: This function is inaccessible to the outside due to the double |
| // module wrapping it. It is called exactly once by the C side via its |
| // unique name. |
| unsafe {{ __init() }} |
| }} |
| |
| #[cfg(MODULE)] |
| #[doc(hidden)] |
| #[no_mangle] |
| pub extern \"C\" fn cleanup_module() {{ |
| // SAFETY: |
| // - This function is inaccessible to the outside due to the double |
| // module wrapping it. It is called exactly once by the C side via its |
| // unique name, |
| // - furthermore it is only called after `init_module` has returned `0` |
| // (which delegates to `__init`). |
| unsafe {{ __exit() }} |
| }} |
| |
| // Built-in modules are initialized through an initcall pointer |
| // and the identifiers need to be unique. |
| #[cfg(not(MODULE))] |
| #[cfg(not(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS))] |
| #[doc(hidden)] |
| #[link_section = \"{initcall_section}\"] |
| #[used] |
| pub static __{name}_initcall: extern \"C\" fn() -> core::ffi::c_int = __{name}_init; |
| |
| #[cfg(not(MODULE))] |
| #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)] |
| core::arch::global_asm!( |
| r#\".section \"{initcall_section}\", \"a\" |
| __{name}_initcall: |
| .long __{name}_init - . |
| .previous |
| \"# |
| ); |
| |
| #[cfg(not(MODULE))] |
| #[doc(hidden)] |
| #[no_mangle] |
| pub extern \"C\" fn __{name}_init() -> core::ffi::c_int {{ |
| // SAFETY: This function is inaccessible to the outside due to the double |
| // module wrapping it. It is called exactly once by the C side via its |
| // placement above in the initcall section. |
| unsafe {{ __init() }} |
| }} |
| |
| #[cfg(not(MODULE))] |
| #[doc(hidden)] |
| #[no_mangle] |
| pub extern \"C\" fn __{name}_exit() {{ |
| // SAFETY: |
| // - This function is inaccessible to the outside due to the double |
| // module wrapping it. It is called exactly once by the C side via its |
| // unique name, |
| // - furthermore it is only called after `__{name}_init` has returned `0` |
| // (which delegates to `__init`). |
| unsafe {{ __exit() }} |
| }} |
| |
| /// # Safety |
| /// |
| /// This function must only be called once. |
| unsafe fn __init() -> core::ffi::c_int {{ |
| match <{type_} as kernel::Module>::init(&super::super::THIS_MODULE) {{ |
| Ok(m) => {{ |
| // SAFETY: No data race, since `__MOD` can only be accessed by this |
| // module and there only `__init` and `__exit` access it. These |
| // functions are only called once and `__exit` cannot be called |
| // before or during `__init`. |
| unsafe {{ |
| __MOD = Some(m); |
| }} |
| return 0; |
| }} |
| Err(e) => {{ |
| return e.to_errno(); |
| }} |
| }} |
| }} |
| |
| /// # Safety |
| /// |
| /// This function must |
| /// - only be called once, |
| /// - be called after `__init` has been called and returned `0`. |
| unsafe fn __exit() {{ |
| // SAFETY: No data race, since `__MOD` can only be accessed by this module |
| // and there only `__init` and `__exit` access it. These functions are only |
| // called once and `__init` was already called. |
| unsafe {{ |
| // Invokes `drop()` on `__MOD`, which should be used for cleanup. |
| __MOD = None; |
| }} |
| }} |
| |
| {modinfo} |
| }} |
| }} |
| ", |
| type_ = info.type_, |
| name = info.name, |
| modinfo = modinfo.buffer, |
| initcall_section = ".initcall6.init" |
| ) |
| .parse() |
| .expect("Error parsing formatted string into token stream.") |
| } |