Having investigated this myself, I would be very surprised to discover that it is.
The only viable solution to make AsyncRead zero cost for io-uring would be to have required futures to be polled to completion before they are dropped. So you can give up on select and most necessary concurrency primitives. You really want to be able to stop running futures you don't need, after all.
If you want the kernel to own the buffer, you should just let the kernel own the buffer. Therefore, AsyncBufRead. This will require the ecosystem to shift where the buffer is owned, of course, and that's a cost of moving to io-uring. Tough, but those are the cards we were dealt.
Having investigated this myself, I would be very surprised to discover that it is.
The only viable solution to make AsyncRead zero cost for io-uring would be to have required futures to be polled to completion before they are dropped. So you can give up on select and most necessary concurrency primitives. You really want to be able to stop running futures you don't need, after all.
If you want the kernel to own the buffer, you should just let the kernel own the buffer. Therefore, AsyncBufRead. This will require the ecosystem to shift where the buffer is owned, of course, and that's a cost of moving to io-uring. Tough, but those are the cards we were dealt.