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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 o= nly > need to call `pad_to_align()`, say, if you are computing a layout or incr= easing > 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. [1] https://lore.kernel.org/all/DGUZ4A6W87JU.36R2KDR7YGSEX@kernel.org/