Re: [PATCH 2/5] rust: bits: add define_flags macro

[Daniel Almeida <daniel.almeida@collabora.com>]

Igor,

> On 31 Jan 2026, at 11:12, Igor Korotin via B4 Relay <devnull+igor.korotin.linux.gmail.com@kernel.org> wrote:
> 
> From: Igor Korotin <igor.korotin.linux@gmail.com>
> 
> introduce define_flags macro that incorporates BitOr BitAnd and Not
> implementations.
> 
> Signed-off-by: Igor Korotin <igor.korotin.linux@gmail.com>
> ---
> rust/kernel/bits.rs | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 57 insertions(+)
> 
> diff --git a/rust/kernel/bits.rs b/rust/kernel/bits.rs
> index 553d50265883..6750aef18708 100644
> --- a/rust/kernel/bits.rs
> +++ b/rust/kernel/bits.rs
> @@ -201,3 +201,60 @@ pub const fn [<genmask_ $ty>](range: RangeInclusive<u32>) -> $ty {
>     /// assert_eq!(genmask_u8(0..=7), u8::MAX);
>     /// ```
> );
> +
> +/// defines flags
> +#[macro_export]
> +macro_rules! define_flags {
> +    (
> +        $gen_name:ident($gen_type:ident),
> +        $($variant:ident = $binding:expr,)+
> +    ) => {
> +        /// Flags that can be combined with the operators `|`, `&`, and `!`.
> +        ///
> +        /// Values can be used from the [`flags`] module.
> +        #[derive(Clone, Copy, PartialEq)]
> +        pub struct $gen_name($gen_type);
> +
> +        impl $gen_name {
> +            /// Get the raw representation of this flag.
> +            pub(crate) fn as_raw(self) -> $gen_type {
> +                self.0
> +            }
> +
> +            /// Check whether `flags` is contained in `self`.
> +            pub fn contains(self, flags: $gen_name) -> bool {
> +                (self & flags) == flags
> +            }
> +        }
> +
> +        impl core::ops::BitOr for $gen_name {
> +            type Output = $gen_name;
> +            fn bitor(self, rhs: Self) -> Self::Output {
> +                Self(self.0 | rhs.0)
> +            }
> +        }
> +
> +        impl core::ops::BitAnd for $gen_name {
> +            type Output = $gen_name;
> +            fn bitand(self, rhs: Self) -> Self::Output {
> +                Self(self.0 & rhs.0)
> +            }
> +        }
> +
> +        impl core::ops::Not for $gen_name {
> +            type Output = $gen_name;
> +            fn not(self) -> Self::Output {
> +                Self(!self.0)
> +            }
> +        }
> +
> +        #[allow(missing_docs)]
> +        pub mod flags {
> +            use super::$gen_name;
> +            $(
> +                #[allow(missing_docs)]
> +                pub const $variant: $gen_name = $gen_name($binding as $gen_type);
> +            )+
> +        }
> +    }
> +}
> 
> -- 
> 2.43.0
> 
> 
> 

Please drop this patch in favor of the patch from Filipe Xavier. It does the same thing.

— Daniel