Re: [PATCH 1/7] rust: dma: add from-slice constructors for Coherent and CoherentBox

[Miguel Ojeda]

On Thu, Mar 26, 2026 at 3:59 PM Alexandre Courbot <acourbot@xxxxxxxxxx> wrote:
>
> Then it looks like this:
>
>     let mut slice = Self(Coherent::<T>::alloc_slice_with_attrs(
>         dev,
>         data.len(),
>         gfp_flags,
>         dma_attrs,
>     )?);
>
>     // PANIC: `slice` was created with length `data.len()`.
>     slice.copy_from_slice(data);
>
>     Ok(slice)

Hmm... I think I prefer this version because (conceptually) it has
less calls, closures and conditionals (i.e. 2 `map`s vs. 1 `?`). Of
course, it should compile to the same thing.

In general, I think removing wrapper types early is better than
carrying them around. It also seems closer spiritually to the early
return style of the kernel in the C side.

For this case, I think both are understandable anyway.

Cheers,
Miguel