Re: [PATCH v3 2/2] rust: add dma coherent allocator abstraction.

[Abdiel Janulgue]

On 04/11/2024 11:31, Alice Ryhl wrote:
> On Mon, Nov 4, 2024 at 10:07 AM Abdiel Janulgue
> <abdiel.janulgue@xxxxxxxxx> wrote:
> > +/// Abstraction of dma_alloc_coherent
> > +///
> > +/// # Invariants
> > +///
> > +/// For the lifetime of an instance of CoherentAllocation, the cpu address is a valid pointer
> > +/// to an allocated region of consistent memory and we hold a reference to the device.
> > +pub struct CoherentAllocation<T: Add> {
>
> Requiring `T: Add` is very unusual. Why?
>
> I don't even see any additions anywhere.
>
> Alice

Background here:
https://lore.kernel.org/all/ee45ae5f-133d-4d38-bb4a-d3515790feb4@xxxxxxxxx/

Basically this aims to restrict the abstraction to non-ZST types. Are 
there better (clever) ways to do this?

Thanks!

/Abdiel