On Thu, Jul 09, 2020 at 12:50:27PM -0600, Jens Axboe wrote:

It might, if you have IRQ context for the completion. task_work isn't
expensive, however. It's not like a thread offload.

quoted

Using flags have not been liked here, but given the upheaval involved so
far I have begun to feel - it was keeping things simple. Should it be
reconsidered?

It's definitely worth considering, especially since we can use cflags
like Pavel suggested upfront and not need any extra storage. But it
brings us back to the 32-bit vs 64-bit discussion, and then using blocks
instead of bytes. Which isn't exactly super pretty.

block doesn't work for the case of writes to files that don't have
to be aligned in any way.  And that I think is the more broadly
applicable use case than zone append on block devices.