Add support for generic parameters defaults in `#[pin_data]` by using
the newly introduced `decl_generics` instead of the `impl_generics`.
Before this would not compile:
#[pin_data]
struct Foo<const N: usize = 0> {
// ...
}
because it would be expanded to this:
struct Foo<const N: usize = 0> {
// ...
}
const _: () = {
struct __ThePinData<const N: usize = 0> {
__phantom: ::core::marker::PhantomData<fn(Foo<N>) -> Foo<N>>,
}
impl<const N: usize = 0> ::core::clone::Clone for __ThePinData<N> {
fn clone(&self) -> Self {
*self
}
}
// [...] rest of expansion omitted
};
The problem is with the `impl<const N: usize = 0>`, since that is
invalid Rust syntax. It should not mention the default value at all,
since default values only make sense on type definitions.
The new `impl_generics` do not contain the default values, thus
generating correct Rust code.
This is used by the next commit that puts `#[pin_data]` on
`kernel::workqueue::Work`.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240309155243.482334-2-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The generic parameters on a type definition can specify default values.
Currently `parse_generics()` cannot handle this though. For example when
parsing the following generics:
<T: Clone, const N: usize = 0>
The `impl_generics` will be set to `T: Clone, const N: usize = 0` and
`ty_generics` will be set to `T, N`. Now using the `impl_generics` on an
impl block:
impl<$($impl_generics)*> Foo {}
will result in invalid Rust code, because default values are only
available on type definitions.
Therefore add parsing support for generic parameter default values using
a new kind of generics called `decl_generics` and change the old
behavior of `impl_generics` to not contain the generic parameter default
values.
Now `Generics` has three fields:
- `impl_generics`: the generics with bounds
(e.g. `T: Clone, const N: usize`)
- `decl_generics`: the generics with bounds and default values
(e.g. `T: Clone, const N: usize = 0`)
- `ty_generics`: contains the generics without bounds and without
default values (e.g. `T, N`)
`impl_generics` is designed to be used on `impl<$impl_generics>`,
`decl_generics` for the type definition, so `struct Foo<$decl_generics>`
and `ty_generics` whenever you use the type, so `Foo<$ty_generics>`.
Here is an example that uses all three different types of generics:
let (Generics { decl_generics, impl_generics, ty_generics }, rest) = parse_generics(input);
quote! {
struct Foo<$($decl_generics)*> {
// ...
}
impl<$impl_generics> Foo<$ty_generics> {
fn foo() {
// ...
}
}
}
The next commit contains a fix to the `#[pin_data]` macro making it
compatible with generic parameter default values by relying on this new
behavior.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240309155243.482334-1-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Other macros might also want to parse generics. Additionally this makes
the code easier to read, as the next commit will introduce more code in
`#[pin_data]`. Also add more comments to explain how parsing generics
work.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20230424081112.99890-2-benno.lossin@proton.me
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Modules can (and usually do) have multiple alias tags, in order to
specify multiple possible device matches for autoloading. Allow this by
changing the alias ModuleInfo field to an Option<Vec<String>>.
Note: For normal device IDs this is autogenerated by modpost (which is
not properly integrated with Rust support yet), so it is useful to be
able to manually add device match aliases for now, and should still be
useful in the future for corner cases that modpost does not handle.
This pulls in the expect_group() helper from the rfl/rust branch
(with credit to authors).
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Co-developed-by: Finn Behrens <me@kloenk.dev>
Signed-off-by: Finn Behrens <me@kloenk.dev>
Co-developed-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Signed-off-by: Asahi Lina <lina@asahilina.net>
Link: https://lore.kernel.org/r/20230224-rust-macros-v2-1-7396e8b7018d@asahilina.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Instead of taking binary string literals, take string ones instead,
making it easier for users to define a module, i.e. instead of
calling `module!` like:
module! {
...
name: b"rust_minimal",
...
}
now it is called as:
module! {
...
name: "rust_minimal",
...
}
Module names, aliases and license strings are restricted to
ASCII only. However, the author and the description allows UTF-8.
For simplicity (avoid parsing), escape sequences and raw string
literals are not yet handled.
Link: https://github.com/Rust-for-Linux/linux/issues/252
Link: https://lore.kernel.org/lkml/YukvvPOOu8uZl7+n@yadro.com/
Signed-off-by: Gary Guo <gary@garyguo.net>
[Reworded, adapted for upstream and applied latest changes]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This crate contains all the procedural macros ("proc macros")
shared by all the kernel.
Procedural macros allow to create syntax extensions. They run at
compile-time and can consume as well as produce Rust syntax.
For instance, the `module!` macro that is used by Rust modules
is implemented here. It allows to easily declare the equivalent
information to the `MODULE_*` macros in C modules, e.g.:
module! {
type: RustMinimal,
name: b"rust_minimal",
author: b"Rust for Linux Contributors",
description: b"Rust minimal sample",
license: b"GPL",
}
Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Co-developed-by: Finn Behrens <me@kloenk.de>
Signed-off-by: Finn Behrens <me@kloenk.de>
Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com>
Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Co-developed-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
Co-developed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Matthew Bakhtiari <dev@mtbk.me>
Signed-off-by: Matthew Bakhtiari <dev@mtbk.me>
Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
