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Implement `SizeConstants` for `Alignment` and add some more > size constants (mirroring include/linux/sizes.h) so we can write e.g. > `Alignment::SZ_8` instead. These are two good ideas, but since they are orthogonal they ought to be in their own separate patch. :) <...> > @@ -99,13 +125,22 @@ macro_rules! define_sizes { > /// choose the width that matches their hardware. All `SZ_*` val= ues fit > /// in a [`u32`], so all implementations are lossless. > /// > + /// Also implemented for [`Alignment`], providing each size as a > + /// compile-time validated alignment. > + /// > + /// [`Alignment`]: crate::ptr::Alignment > + /// > /// # Examples > /// > /// ``` > - /// use kernel::sizes::SizeConstants; > + /// use kernel::{ > + /// ptr::Alignment, > + /// sizes::SizeConstants, // > + /// }; > /// > /// let gpu_heap =3D 14 * u64::SZ_1M; > /// let mmio_window =3D u32::SZ_16M; > + /// let page_align =3D Alignment::SZ_4K; > /// ``` > pub trait SizeConstants { > $( > @@ -117,6 +152,16 @@ pub trait SizeConstants { > =20 > (@impls [] $($(#[$meta:meta])* $name:ident,)*) =3D> {}; > =20 > + (@impl_alignment $($(#[$meta:meta])* $name:ident,)*) =3D> { > + impl SizeConstants for crate::ptr::Alignment { > + $( > + $(#[$meta])* > + // A non-power-of-two constant will fail the build here = if used. > + const $name: Self =3D crate::ptr::Alignment::new_checked= (self::$name).unwrap(); Since this is a const, you can use: const $name: Self =3D crate::ptr::Alignment::new::<{ self::$name }>(); Which we should prefer over using `unwrap`, even compile-time checked ones.