Linus Torvalds
5ce3307b6d
Pull io_uring fixes from Jens Axboe:
"This is mostly io_uring fixes/tweaks. Most of these were actually done
in time for the last -rc, but I wanted to ensure that everything
tested out great before including them. The code delta looks larger
than it really is, as it's mostly just comment additions/changes.
Outside of the comment additions/changes, this is mostly removal of
unnecessary barriers. In all, this pull request contains:
- Tweak to how we handle errors at submission time. We now post a
completion event if the error occurs on behalf of an sqe, instead
of returning it through the system call. If the error happens
outside of a specific sqe, we return the error through the system
call. This makes it nicer to use and makes the "normal" use case
behave the same as the offload cases. (me)
- Fix for a missing req reference drop from async context (me)
- If an sqe is submitted with RWF_NOWAIT, don't punt it to async
context. Return -EAGAIN directly, instead of using it as a hint to
do async punt. (Stefan)
- Fix notes on barriers (Stefan)
- Remove unnecessary barriers (Stefan)
- Fix potential double free of memory in setup error (Mark)
- Further improve sq poll CPU validation (Mark)
- Fix page allocation warning and leak on buffer registration error
(Mark)
- Fix iov_iter_type() for new no-ref flag (Ming)
- Fix a case where dio doesn't honor bio no-page-ref (Ming)"
* tag 'for-linus-20190502' of git://git.kernel.dk/linux-block:
io_uring: avoid page allocation warnings
iov_iter: fix iov_iter_type
block: fix handling for BIO_NO_PAGE_REF
io_uring: drop req submit reference always in async punt
io_uring: free allocated io_memory once
io_uring: fix SQPOLL cpu validation
io_uring: have submission side sqe errors post a cqe
io_uring: remove unnecessary barrier after unsetting IORING_SQ_NEED_WAKEUP
io_uring: remove unnecessary barrier after incrementing dropped counter
io_uring: remove unnecessary barrier before reading SQ tail
io_uring: remove unnecessary barrier after updating SQ head
io_uring: remove unnecessary barrier before reading cq head
io_uring: remove unnecessary barrier before wq_has_sleeper
io_uring: fix notes on barriers
io_uring: fix handling SQEs requesting NOWAIT
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