Re: [PATCH 05/79] block: rust: change `queue_rq` request type to `Owned`

[Alice Ryhl]

On Mon, Feb 16, 2026 at 12:34:52AM +0100, Andreas Hindborg wrote:
> Simplify the reference counting scheme for `Request` from 4 states to 3
> states. This is achieved by coalescing the zero state between block layer
> owned and uniquely owned by driver.
> 
> Implement `Ownable` for `Request` and deliver `Request` to drivers as
> `Owned<Request>`. In this process:
> 
>  - Move uniqueness assertions out of `rnull` as these are now guaranteed by
>    the `Owned` type.
>  - Move `start_unchecked`, `try_set_end` and `end_ok` from `Request` to
>    `Owned<Request>`, relying on type invariant for uniqueness.
> 
> Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>

It would be a lot cleaner if we could implement HrTimerPointer for
Owned<Request> and entirely get rid of the refcount in request so we
don't need ARef<Request> at all.

Is there a reason we *need* ARef here?

Alice