Re: [PATCH v3 1/2] rust: sizes: add DeviceSize trait for device address space constants

[Danilo Krummrich]

On Fri Apr 3, 2026 at 3:36 AM CEST, John Hubbard wrote:
> On 4/1/26 6:42 PM, Alexandre Courbot wrote:
>> On Thu Apr 2, 2026 at 6:20 AM JST, Danilo Krummrich wrote:
>>> On Wed Apr 1, 2026 at 10:22 PM CEST, John Hubbard wrote:
>>>> On 4/1/26 2:46 AM, Alice Ryhl wrote:
> ...
>>> The reason is that when I proposed this I was thinking of it as a marker trait
>>> for "complex" types around u32, u64, etc. that we can use in DRM APIs (or any
>>> other device centric API) though generics.
>>>
>>> For instance, instead of GpuVm<T>::vm_start() -> u64, it could be
>>> GpuVm<T, V: DeviceSize>::vm_start() -> V.
>> 
>> With the proposed naming this becomes `GpuVm<T, V: SizeConstants>`. Why
>> not just name it `Size`? Sure it's a very common word, but we have the
>> module to scope the name properly.
>
> I was waiting to see if anyone else weighed in.
>
> SizeConstants accurately describes what this trait provides. Size is
> too general. Again, I think it's best to name things for what they
> are or what they provide. And then, if they look odd in some use case,
> that's a hint to consider if that use case is precisely the best way
> to compose what you want to do.
>
> Anyway, I'm pretty sold on SizeConstants, so I'm hoping to stay with
> that, are you OK with it?

As mentioned no complaints from my side, but I think it would be good to add a
TODO for creating those type wrappers; the name can be revisited in this context
or a separate marker trait introduced.