diff options
Diffstat (limited to 'rust/macros/module.rs')
| -rw-r--r-- | rust/macros/module.rs | 485 |
1 files changed, 374 insertions, 111 deletions
diff --git a/rust/macros/module.rs b/rust/macros/module.rs index a7e363c2b044..80cb9b16f5aa 100644 --- a/rust/macros/module.rs +++ b/rust/macros/module.rs @@ -1,13 +1,32 @@ // SPDX-License-Identifier: GPL-2.0 use crate::helpers::*; -use proc_macro::{token_stream, Literal, TokenStream, TokenTree}; +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, + param_buffer: String, } impl<'a> ModInfoBuilder<'a> { @@ -16,10 +35,11 @@ impl<'a> ModInfoBuilder<'a> { module, counter: 0, buffer: String::new(), + param_buffer: String::new(), } } - fn emit_base(&mut self, field: &str, content: &str, builtin: bool) { + fn emit_base(&mut self, field: &str, content: &str, builtin: bool, param: bool) { let string = if builtin { // Built-in modules prefix their modinfo strings by `module.`. format!( @@ -30,16 +50,22 @@ impl<'a> ModInfoBuilder<'a> { ) } else { // Loadable modules' modinfo strings go as-is. - format!("{field}={content}\0", field = field, content = content) + format!("{field}={content}\0") + }; + + let buffer = if param { + &mut self.param_buffer + } else { + &mut self.buffer }; write!( - &mut self.buffer, + buffer, " {cfg} #[doc(hidden)] - #[link_section = \".modinfo\"] - #[used] + #[cfg_attr(not(target_os = \"macos\"), link_section = \".modinfo\")] + #[used(compiler)] pub static __{module}_{counter}: [u8; {length}] = *{string}; ", cfg = if builtin { @@ -57,36 +83,190 @@ impl<'a> ModInfoBuilder<'a> { self.counter += 1; } - fn emit_only_builtin(&mut self, field: &str, content: &str) { - self.emit_base(field, content, true) + fn emit_only_builtin(&mut self, field: &str, content: &str, param: bool) { + self.emit_base(field, content, true, param) } - fn emit_only_loadable(&mut self, field: &str, content: &str) { - self.emit_base(field, content, false) + fn emit_only_loadable(&mut self, field: &str, content: &str, param: bool) { + self.emit_base(field, content, false, param) } fn emit(&mut self, field: &str, content: &str) { - self.emit_only_builtin(field, content); - self.emit_only_loadable(field, content); + self.emit_internal(field, content, false); + } + + fn emit_internal(&mut self, field: &str, content: &str, param: bool) { + self.emit_only_builtin(field, content, param); + self.emit_only_loadable(field, content, param); + } + + fn emit_param(&mut self, field: &str, param: &str, content: &str) { + let content = format!("{param}:{content}", param = param, content = content); + self.emit_internal(field, &content, true); + } + + fn emit_params(&mut self, info: &ModuleInfo) { + let Some(params) = &info.params else { + return; + }; + + for param in params { + let ops = param_ops_path(¶m.ptype); + + // Note: The spelling of these fields is dictated by the user space + // tool `modinfo`. + self.emit_param("parmtype", ¶m.name, ¶m.ptype); + self.emit_param("parm", ¶m.name, ¶m.description); + + write!( + self.param_buffer, + " + pub(crate) static {param_name}: + ::kernel::module_param::ModuleParamAccess<{param_type}> = + ::kernel::module_param::ModuleParamAccess::new({param_default}); + + const _: () = {{ + #[link_section = \"__param\"] + #[used] + static __{module_name}_{param_name}_struct: + ::kernel::module_param::KernelParam = + ::kernel::module_param::KernelParam::new( + ::kernel::bindings::kernel_param {{ + name: if ::core::cfg!(MODULE) {{ + ::kernel::c_str!(\"{param_name}\").to_bytes_with_nul() + }} else {{ + ::kernel::c_str!(\"{module_name}.{param_name}\") + .to_bytes_with_nul() + }}.as_ptr(), + // SAFETY: `__this_module` is constructed by the kernel at load + // time and will not be freed until the module is unloaded. + #[cfg(MODULE)] + mod_: unsafe {{ + core::ptr::from_ref(&::kernel::bindings::__this_module) + .cast_mut() + }}, + #[cfg(not(MODULE))] + mod_: ::core::ptr::null_mut(), + ops: core::ptr::from_ref(&{ops}), + perm: 0, // Will not appear in sysfs + level: -1, + flags: 0, + __bindgen_anon_1: ::kernel::bindings::kernel_param__bindgen_ty_1 {{ + arg: {param_name}.as_void_ptr() + }}, + }} + ); + }}; + ", + module_name = info.name, + param_type = param.ptype, + param_default = param.default, + param_name = param.name, + ops = ops, + ) + .unwrap(); + } + } +} + +fn param_ops_path(param_type: &str) -> &'static str { + match param_type { + "i8" => "::kernel::module_param::PARAM_OPS_I8", + "u8" => "::kernel::module_param::PARAM_OPS_U8", + "i16" => "::kernel::module_param::PARAM_OPS_I16", + "u16" => "::kernel::module_param::PARAM_OPS_U16", + "i32" => "::kernel::module_param::PARAM_OPS_I32", + "u32" => "::kernel::module_param::PARAM_OPS_U32", + "i64" => "::kernel::module_param::PARAM_OPS_I64", + "u64" => "::kernel::module_param::PARAM_OPS_U64", + "isize" => "::kernel::module_param::PARAM_OPS_ISIZE", + "usize" => "::kernel::module_param::PARAM_OPS_USIZE", + t => panic!("Unsupported parameter type {}", t), } } +fn expect_param_default(param_it: &mut token_stream::IntoIter) -> String { + assert_eq!(expect_ident(param_it), "default"); + assert_eq!(expect_punct(param_it), ':'); + let sign = try_sign(param_it); + let default = try_literal(param_it).expect("Expected default param value"); + assert_eq!(expect_punct(param_it), ','); + let mut value = sign.map(String::from).unwrap_or_default(); + value.push_str(&default); + value +} + #[derive(Debug, Default)] struct ModuleInfo { type_: String, license: String, name: String, - author: Option<String>, + authors: Option<Vec<String>>, description: Option<String>, - alias: Option<String>, + alias: Option<Vec<String>>, + firmware: Option<Vec<String>>, + imports_ns: Option<Vec<String>>, + params: Option<Vec<Parameter>>, +} + +#[derive(Debug)] +struct Parameter { + name: String, + ptype: String, + default: String, + description: String, +} + +fn expect_params(it: &mut token_stream::IntoIter) -> Vec<Parameter> { + let params = expect_group(it); + assert_eq!(params.delimiter(), Delimiter::Brace); + let mut it = params.stream().into_iter(); + let mut parsed = Vec::new(); + + loop { + let param_name = match it.next() { + Some(TokenTree::Ident(ident)) => ident.to_string(), + Some(_) => panic!("Expected Ident or end"), + None => break, + }; + + assert_eq!(expect_punct(&mut it), ':'); + let param_type = expect_ident(&mut it); + let group = expect_group(&mut it); + assert_eq!(group.delimiter(), Delimiter::Brace); + assert_eq!(expect_punct(&mut it), ','); + + let mut param_it = group.stream().into_iter(); + let param_default = expect_param_default(&mut param_it); + let param_description = expect_string_field(&mut param_it, "description"); + expect_end(&mut param_it); + + parsed.push(Parameter { + name: param_name, + ptype: param_type, + default: param_default, + description: param_description, + }) + } + + parsed } 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 EXPECTED_KEYS: &[&str] = &[ + "type", + "name", + "authors", + "description", + "license", + "alias", + "firmware", + "imports_ns", + "params", + ]; const REQUIRED_KEYS: &[&str] = &["type", "name", "license"]; let mut seen_keys = Vec::new(); @@ -98,10 +278,7 @@ impl ModuleInfo { }; if seen_keys.contains(&key) { - panic!( - "Duplicated key \"{}\". Keys can only be specified once.", - key - ); + panic!("Duplicated key \"{key}\". Keys can only be specified once."); } assert_eq!(expect_punct(it), ':'); @@ -109,14 +286,14 @@ impl ModuleInfo { match key.as_str() { "type" => info.type_ = expect_ident(it), "name" => info.name = expect_string_ascii(it), - "author" => info.author = Some(expect_string(it)), + "authors" => info.authors = Some(expect_string_array(it)), "description" => info.description = Some(expect_string(it)), "license" => info.license = expect_string_ascii(it), - "alias" => info.alias = Some(expect_string_ascii(it)), - _ => panic!( - "Unknown key \"{}\". Valid keys are: {:?}.", - key, EXPECTED_KEYS - ), + "alias" => info.alias = Some(expect_string_array(it)), + "firmware" => info.firmware = Some(expect_string_array(it)), + "imports_ns" => info.imports_ns = Some(expect_string_array(it)), + "params" => info.params = Some(expect_params(it)), + _ => panic!("Unknown key \"{key}\". Valid keys are: {EXPECTED_KEYS:?}."), } assert_eq!(expect_punct(it), ','); @@ -128,7 +305,7 @@ impl ModuleInfo { for key in REQUIRED_KEYS { if !seen_keys.iter().any(|e| e == key) { - panic!("Missing required key \"{}\".", key); + panic!("Missing required key \"{key}\"."); } } @@ -140,10 +317,7 @@ impl ModuleInfo { } if seen_keys != ordered_keys { - panic!( - "Keys are not ordered as expected. Order them like: {:?}.", - ordered_keys - ); + panic!("Keys are not ordered as expected. Order them like: {ordered_keys:?}."); } info @@ -155,22 +329,40 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { 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); + // Rust does not allow hyphens in identifiers, use underscore instead. + let ident = info.name.replace('-', "_"); + let mut modinfo = ModInfoBuilder::new(ident.as_ref()); + if let Some(authors) = &info.authors { + for author in authors { + modinfo.emit("author", author); + } } - if let Some(description) = info.description { - modinfo.emit("description", &description); + if let Some(description) = &info.description { + modinfo.emit("description", description); } modinfo.emit("license", &info.license); - if let Some(alias) = info.alias { - modinfo.emit("alias", &alias); + if let Some(aliases) = &info.alias { + for alias in aliases { + modinfo.emit("alias", alias); + } + } + if let Some(firmware) = &info.firmware { + for fw in firmware { + modinfo.emit("firmware", fw); + } + } + if let Some(imports) = &info.imports_ns { + for ns in imports { + modinfo.emit("import_ns", ns); + } } // 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); + modinfo.emit_only_builtin("file", &file, false); + + modinfo.emit_params(&info); format!( " @@ -179,102 +371,173 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream { /// Used by the printing macros, e.g. [`info!`]. const __LOG_PREFIX: &[u8] = b\"{name}\\0\"; - /// The \"Rust loadable module\" mark, for `scripts/is_rust_module.sh`. - // - // 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; - // 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 _) + static THIS_MODULE: ::kernel::ThisModule = unsafe {{ + extern \"C\" {{ + static __this_module: ::kernel::types::Opaque<::kernel::bindings::module>; + }} + + ::kernel::ThisModule::from_ptr(__this_module.get()) }}; #[cfg(not(MODULE))] - static THIS_MODULE: kernel::ThisModule = unsafe {{ - kernel::ThisModule::from_ptr(core::ptr::null_mut()) + static THIS_MODULE: ::kernel::ThisModule = unsafe {{ + ::kernel::ThisModule::from_ptr(::core::ptr::null_mut()) }}; - // Loadable modules need to export the `{{init,cleanup}}_module` identifiers. - #[cfg(MODULE)] - #[doc(hidden)] - #[no_mangle] - pub extern \"C\" fn init_module() -> core::ffi::c_int {{ - __init() - }} + /// The `LocalModule` type is the type of the module created by `module!`, + /// `module_pci_driver!`, `module_platform_driver!`, etc. + type LocalModule = {type_}; - #[cfg(MODULE)] - #[doc(hidden)] - #[no_mangle] - pub extern \"C\" fn cleanup_module() {{ - __exit() + impl ::kernel::ModuleMetadata for {type_} {{ + const NAME: &'static ::kernel::str::CStr = c\"{name}\"; }} - // 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; + // Double nested modules, since then nobody can access the public items inside. + mod __module_init {{ + mod __module_init {{ + use super::super::{type_}; + use pin_init::PinInit; + + /// 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(compiler)] + static __IS_RUST_MODULE: () = (); + + static mut __MOD: ::core::mem::MaybeUninit<{type_}> = + ::core::mem::MaybeUninit::uninit(); + + // 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() -> ::kernel::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(not(MODULE))] - #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)] - core::arch::global_asm!( - r#\".section \"{initcall_section}\", \"a\" - __{name}_initcall: - .long __{name}_init - . - .previous - \"# - ); + #[cfg(MODULE)] + #[doc(hidden)] + #[used(compiler)] + #[link_section = \".init.data\"] + static __UNIQUE_ID___addressable_init_module: unsafe extern \"C\" fn() -> i32 = init_module; + + #[cfg(MODULE)] + #[doc(hidden)] + #[no_mangle] + #[link_section = \".exit.text\"] + 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() }} + }} - #[cfg(not(MODULE))] - #[doc(hidden)] - #[no_mangle] - pub extern \"C\" fn __{name}_init() -> core::ffi::c_int {{ - __init() - }} + #[cfg(MODULE)] + #[doc(hidden)] + #[used(compiler)] + #[link_section = \".exit.data\"] + static __UNIQUE_ID___addressable_cleanup_module: extern \"C\" fn() = cleanup_module; + + // 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(compiler)] + pub static __{ident}_initcall: extern \"C\" fn() -> + ::kernel::ffi::c_int = __{ident}_init; + + #[cfg(not(MODULE))] + #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)] + ::core::arch::global_asm!( + r#\".section \"{initcall_section}\", \"a\" + __{ident}_initcall: + .long __{ident}_init - . + .previous + \"# + ); + + #[cfg(not(MODULE))] + #[doc(hidden)] + #[no_mangle] + pub extern \"C\" fn __{ident}_init() -> ::kernel::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() {{ - __exit() - }} + #[cfg(not(MODULE))] + #[doc(hidden)] + #[no_mangle] + pub extern \"C\" fn __{ident}_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 `__{ident}_init` has + // returned `0` (which delegates to `__init`). + unsafe {{ __exit() }} + }} - fn __init() -> core::ffi::c_int {{ - match <{type_} as kernel::Module>::init(&THIS_MODULE) {{ - Ok(m) => {{ - unsafe {{ - __MOD = Some(m); + /// # Safety + /// + /// This function must only be called once. + unsafe fn __init() -> ::kernel::ffi::c_int {{ + let initer = + <{type_} as ::kernel::InPlaceModule>::init(&super::super::THIS_MODULE); + // 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`. + match unsafe {{ initer.__pinned_init(__MOD.as_mut_ptr()) }} {{ + Ok(m) => 0, + Err(e) => e.to_errno(), }} - return 0; }} - Err(e) => {{ - return e.to_kernel_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.assume_init_drop(); + }} }} + {modinfo} }} }} - - fn __exit() {{ - unsafe {{ - // Invokes `drop()` on `__MOD`, which should be used for cleanup. - __MOD = None; - }} + mod module_parameters {{ + {params} }} - - {modinfo} ", type_ = info.type_, name = info.name, + ident = ident, modinfo = modinfo.buffer, + params = modinfo.param_buffer, initcall_section = ".initcall6.init" ) .parse() |
