On Wed, 16 Aug 2023 at 22:35, David Howells <dhowells@redhat.com> wrote:
>
> I'm not sure that buys us anything.  It would then require every call to
> iov_iter_is_bvec()[*] to check for two values instead of one

Well, that part is trivially fixable, and we should do that anyway for
other reasons.

See the attached patch.

> The issue is that ITER_xyz changes the iteration function - but we don't
> actually want to do that; rather, we need to change the step function.

Yeah, that may be the fundamental issue. But making the ITER_xyz flags
be bit masks would help - partly exactly because it makes it so
trivial yo say "for this set of ITER_xyz, do this".

This patch only does that for the 'user_backed' thing, which was a similar case.

Hmm?

               Linus