Re: [PATCH v2 2/4] rust: iov: add iov_iter abstractions for ITER_DEST

[Alice Ryhl <aliceryhl@google.com>]

On Tue, Jul 08, 2025 at 04:47:51PM +0200, Andreas Hindborg wrote:
> "Alice Ryhl" <aliceryhl@google.com> writes:
> 
> > This adds abstractions for the iov_iter type in the case where
> > data_source is ITER_DEST. This will make Rust implementations of
> > fops->read_iter possible.
> >
> > This series only has support for using existing IO vectors created by C
> > code. Additional abstractions will be needed to support the creation of
> > IO vectors in Rust code.
> >
> > These abstractions make the assumption that `struct iov_iter` does not
> > have internal self-references, which implies that it is valid to move it
> > between different local variables.
> >
> > Signed-off-by: Alice Ryhl <aliceryhl@google.com>
> 
> Please see the comments on v1 [1].
> 
> Best regards,
> Andreas Hindborg
> 
> 
> [1] https://lore.kernel.org/all/439baec2-dba8-4dab-abb5-faa14fbda943@gmail.com

Sorry I should probably have articulated this somewhere. After I looked
at this code with fresh eyes, I realized that the only things the two
types have in common are len, advance, and revert. I didn't think that
attempting to deduplicate the logic was worth it.

Alice