Questions about ProvideBuffers

[espoal]

I'm writing some io_uring examples and I'm currently playing with multishot requests and ProvideBuffers. I have some questions:

• Recently io_uring moved from io_uring_prep_provide_buffers to ring mapped buffers, as explained here. I don't see this change reflected in the API of this crate, am I wrong?
• When I use ProvidedBuffers, how do I signal that some buffers inside a buffer group are ready to be reused? ATM I mark the whole group as available, but is there maybe a way to have more granularity?