io_uring fixes for 5.9-rc2

Hi Linus,

A few io_uring fixes:

- Make sure the head link cancelation includes async work

- Get rid of kiocb_wait_page_queue_init(), makes no sense to have it as a separate function since you moved it into io_uring itself

- io_import_iovec cleanups (Pavel, me)

- Use system_unbound_wq for ring exit work, to avoid spawning tons of these if we have tons of rings exiting at the same time

- Fix req->flags overflow flag manipulation (Pavel)

Please pull!

The following changes since commit 9123e3a74ec7b934a4a099e98af6a61c2f80bbf5:

Linux 5.9-rc1 (2020-08-16 13:04:57 -0700)

are available in the Git repository at:

git://git.kernel.dk/linux-block.git tags/io_uring-5.9-2020-08-21

for you to fetch changes up to 867a23eab52847d41a0a6eae41a64d76de7782a8:

io_uring: kill extra iovec=NULL in import_iovec() (2020-08-20 05:36:19 -0600)

----------------------------------------------------------------
io_uring-5.9-2020-08-21

----------------------------------------------------------------
Jens Axboe (4):
io_uring: find and cancel head link async work on files exit
io_uring: get rid of kiocb_wait_page_queue_init()
io_uring: cleanup io_import_iovec() of pre-mapped request
io_uring: use system_unbound_wq for ring exit work

Pavel Begunkov (3):
io_uring: fix racy req->flags modification
io_uring: comment on kfree(iovec) checks
io_uring: kill extra iovec=NULL in import_iovec()

 fs/io_uring.c | 173 +++++++++++++++++++++++++++-------------------------------
 1 file changed, 79 insertions(+), 94 deletions(-)

Jens Axboe