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Abstractions for the fwctl subsystem. >>> +//! >>> +//! C header: `include/linux/fwctl.h` >>> + >>> +use crate::{ >>> + bindings, >>> + container_of, >>> + device, >>> + prelude::*, >>> + sync::aref::{ >>> + ARef, >>> + AlwaysRefCounted, // >>> + }, >>> + types::Opaque, // >>> +}; >>> +use core::{ >>> + alloc::Layout, >>> + cell::UnsafeCell, >>> + marker::PhantomData, >>> + ptr::NonNull, >>> + slice, // >>> +}; >>> + >>> +/// Returns a kmalloc-compatible allocation size for `T`. >>> +const fn kmalloc_aligned_size() -> usize { >>> + Layout::new::().pad_to_align().size() >> >> What's this function doing? This is just identical to `size_of::()`. >> >> The layout from a specific type is already padded to its alignment. You = only >> need to call `pad_to_align()`, say, if you are computing a layout or inc= reasing >> the alignment of layout. > > IIRC this was meant to be a const version of `Kmalloc::aligned_layout` > [1], which although it is equivalent carries the intent better than just > using `size_of`. But here it would maybe be better to just make > `Kmalloc::aligned_layout` const and call it instead. That'd certainly be better than having a duplicate impl. However, I do wonder if we should just codify the fact that kamlloc works f= or all padded layouts (which is true for all type layouts in Rust) and so we d= on't need to call that (and perhaps also just remove the method). Best, Gary