Pull io_uring updates from Jens Axboe:
- Allocate SQ/CQ ring together, more efficient. Expose this through a
feature flag as well, so we can reduce the number of mmaps by 1
(Hristo and me)
- Fix for sequence logic with SQ thread (Jackie).
- Add support for links with drain commands (Jackie).
- Improved async merging (me)
- Improved buffered async write performance (me)
- Support SQ poll wakeup + event get in single io_uring_enter() (me)
- Support larger SQ ring size. For epoll conversions, the 4k limit was
too small for some prod workloads (Daniel).
- put_user_page() usage (John)
* tag 'for-5.4/io_uring-2019-09-15' of git://git.kernel.dk/linux-block:
io_uring: increase IORING_MAX_ENTRIES to 32K
io_uring: make sqpoll wakeup possible with getevents
io_uring: extend async work merging
io_uring: limit parallelism of buffered writes
io_uring: add io_queue_async_work() helper
io_uring: optimize submit_and_wait API
io_uring: add support for link with drain
io_uring: fix wrong sequence setting logic
io_uring: expose single mmap capability
io_uring: allocate the two rings together
fs/io_uring.c: convert put_page() to put_user_page*()