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| author | Sang-Heon Jeon <ekffu200098@gmail.com> | 2026-08-24 01:18:14 +0900 |
|---|---|---|
| committer | Julia Lawall <Julia.Lawall@inria.fr> | 2026-08-23 22:12:11 +0200 |
| commit | 2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c (patch) | |
| tree | dcc4da1d99f17541c5590ac63c77da4bf372a4ab /rust/macros/vtable.rs | |
| download | linux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.tar.gz linux-stable-2bd30b8dc75b823dd7bbef9d7bc68e1fd7ecee5c.zip | |
coccinelle: alloc_cast: drop removed allocatorsgrafted
- pci_alloc_consistent() and pci_zalloc_consistent() were removed by
commit 7968778914e5
("PCI: Remove the deprecated "pci-dma-compat.h" API")
- kmem_alloc() was removed by commit f078d4ea8276
("xfs: convert kmem_alloc() to kmalloc()")
- kmem_zalloc() was removed by commit 10634530f7ba
("xfs: convert kmem_zalloc() to kzalloc()")
- kmem_zone_alloc() and kmem_zone_zalloc() were removed by commit
bae633a4a283 ("xfs: remove xfs_zone_{alloc,zalloc} helpers")
So drop them from the rules.
No functional change.
Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Diffstat (limited to 'rust/macros/vtable.rs')
| -rw-r--r-- | rust/macros/vtable.rs | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/rust/macros/vtable.rs b/rust/macros/vtable.rs new file mode 100644 index 000000000..be9a5ed8a --- /dev/null +++ b/rust/macros/vtable.rs @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 + +use std::{ + collections::HashSet, + iter::Extend, // +}; + +use proc_macro2::{ + Ident, + TokenStream, // +}; +use quote::ToTokens; +use syn::{ + parse_quote, + Error, + ImplItem, + Item, + ItemImpl, + ItemTrait, + Result, + TraitItem, // +}; + +fn handle_trait(mut item: ItemTrait) -> Result<ItemTrait> { + let mut gen_items = Vec::new(); + + gen_items.push(parse_quote! { + /// A marker to prevent implementors from forgetting to use [`#[vtable]`](vtable) + /// attribute when implementing this trait. + const USE_VTABLE_ATTR: (); + }); + + // Add `type OwnerModule: ModuleMetadata` as a required associated type if + // the trait does not already define it. + if !item + .items + .iter() + .any(|i| matches!(i, TraitItem::Type(t) if t.ident == "OwnerModule")) + { + gen_items.push(parse_quote! { + /// The module implementing this vtable trait. + /// + /// Automatically set to `crate::LocalModule` by the `#[vtable]` + /// impl macro. + type OwnerModule: ::kernel::ModuleMetadata; + }); + } + + for item in &item.items { + if let TraitItem::Fn(fn_item) = item { + let name = &fn_item.sig.ident; + let gen_const_name = Ident::new( + &format!("HAS_{}", name.to_string().to_uppercase()), + name.span(), + ); + + // We don't know on the implementation-site whether a method is required or provided + // so we have to generate a const for all methods. + let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs); + let comment = + format!("Indicates if the `{name}` method is overridden by the implementor."); + gen_items.push(parse_quote! { + #(#cfg_attrs)* + #[doc = #comment] + const #gen_const_name: bool = false; + }); + } + } + + item.items.extend(gen_items); + Ok(item) +} + +fn handle_impl(mut item: ItemImpl) -> Result<ItemImpl> { + let mut gen_items = Vec::new(); + let mut defined_items = HashSet::new(); + + // Iterate over all user-defined items to gather any possible explicit overrides. + for item in &item.items { + match item { + ImplItem::Const(const_item) => { + defined_items.insert(const_item.ident.clone()); + } + ImplItem::Type(type_item) => { + defined_items.insert(type_item.ident.clone()); + } + _ => {} + } + } + + gen_items.push(parse_quote! { + const USE_VTABLE_ATTR: () = (); + }); + + // Auto-insert `type OwnerModule = crate::LocalModule` if not explicitly defined. + // `crate::LocalModule` resolves to the real module type (via `module!`) or a + // dummy fallback in non-module contexts (e.g., doctests). + if !defined_items.contains(&parse_quote!(OwnerModule)) { + gen_items.push(parse_quote! { + type OwnerModule = crate::LocalModule; + }); + } + + for item in &item.items { + if let ImplItem::Fn(fn_item) = item { + let name = &fn_item.sig.ident; + let gen_const_name = Ident::new( + &format!("HAS_{}", name.to_string().to_uppercase()), + name.span(), + ); + // Skip if it's declared already -- this allows user override. + if defined_items.contains(&gen_const_name) { + continue; + } + let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs); + gen_items.push(parse_quote! { + #(#cfg_attrs)* + const #gen_const_name: bool = true; + }); + } + } + + item.items.extend(gen_items); + Ok(item) +} + +pub(crate) fn vtable(input: Item) -> Result<TokenStream> { + match input { + Item::Trait(item) => Ok(handle_trait(item)?.into_token_stream()), + Item::Impl(item) => Ok(handle_impl(item)?.into_token_stream()), + _ => Err(Error::new_spanned( + input, + "`#[vtable]` attribute should only be applied to trait or impl block", + ))?, + } +} |
