Pull io_uring epoll support from Jens Axboe:
"This adds support for reading epoll events via io_uring.
While this may seem counter-intuitive (and/or productive), the
reasoning here is that quite a few existing epoll event loops can
easily do a partial conversion to a completion based model, but are
still stuck with one (or few) event types that remain readiness based.
For that case, they then need to add the io_uring fd to the epoll
context, and continue to rely on epoll_wait(2) for waiting on events.
This misses out on the finer grained waiting that io_uring can do, to
reduce context switches and wait for multiple events in one batch
reliably.
With adding support for reaping epoll events via io_uring, the whole
legacy readiness based event types can still be reaped via epoll, with
the overall waiting in the loop be driven by io_uring"
* tag 'for-6.15/io_uring-epoll-wait-
20250325' of git://git.kernel.dk/linux:
io_uring/epoll: add support for IORING_OP_EPOLL_WAIT
io_uring/epoll: remove CONFIG_EPOLL guards