Re: [PATCH v5 19/20] rust: io: add copying methods

[sashiko-bot@kernel.org]

> One feature that was lost from the old `dma_read!` and `dma_write!` when
> moving to `io_read!` and `io_write!` was the ability to read/write a large
> structs. However, the semantics was unclear to begin with, as there was no
> guarantee about their atomicity even for structs that were small enough to
> fit in u32. Re-introduce the capability in the form of copying methods.
> 
>     dma_read!(foo, bar) -> io_project!(foo, bar).copy_read()
>     dma_write!(foo, bar, baz) -> io_project!(foo, bar).copy_write(baz)
> 
> Model these semantics after memcpy so user has clear expectation of lack of
> atomicity. As an additional benefit of this change, this now works for MMIO
> as well by mapping them to `memcpy_{from,to}io`.
> 
> For slices which is DST so the `copy_read` and `copy_write` API above can't
> work, add `copy_from_slice` and `copy_to_slice` to copy from/to normal
> memory.
> 
> Signed-off-by: Gary Guo <gary@garyguo.net>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260626-io_projection-v5-0-d0961471ae50@garyguo.net?part=19