tree 36e31c3d6eb575289ab4ad10a293c661fa3b8396
parent 23b3628e45924419399da48c2b3a522b05557c91
author Pavel Begunkov <asml.silence@gmail.com> 1595525120 +0300
committer Jens Axboe <axboe@kernel.dk> 1595617246 -0600

io_uring: don't do opcode prep twice

Calling into opcode prep handlers may be dangerous, as they re-read
SQE but might not re-initialise requests completely. If io_req_defer()
passed fast checks and is done with preparations, punt it async.

As all other cases are covered with nulling @sqe, this guarantees that
io_[opcode]_prep() are visited only once per request.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>