With IORING_SETUP_CQE32 ->cqe_cached doesn't store a real address but
rather an implicit offset into cqes. Store the real cqe pointer and
increment it accordingly if CQE32.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1ee1838cba16bed96381a006950b36ba640d998c.1655455613.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

__io_fill_cqe_req() is hot and inlined, we want it to be as small as
possible. Add io_req_cqe_overflow() accepting only a request and doing
all overflow accounting, and replace with it two calls to 6 argument
io_cqring_event_overflow().
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/048b9fbcce56814d77a1a540409c98c3d383edcb.1655455613.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

__io_get_cqe() is not as hot as io_get_cqe(), no need to inline it, it
sheds ~500B from the binary.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c1ac829198a881b7af8710926f99a3559b9f24c0.1655455613.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Deduplicate some code and add a helper for filling an aux CQE, locking
and notification.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b7c6557c8f9dc5c4cfb01292116c682a0ff61081.1655455613.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Currently we do two extra spin lock/unlock pairs to add a poll/apoll
request to the cancellation hash table and remove it from there.

On the submission side we often already hold ->uring_lock and tw
completion is likely to hold it as well. Add a second cancellation hash
table protected by ->uring_lock. In concerns for latency because of a
need to have the mutex locked on the completion side, use the new table
only in following cases:

1) IORING_SETUP_SINGLE_ISSUER: only one task grabs uring_lock, so there
   is little to no contention and so the main tw hander will almost
   always end up grabbing it before calling callbacks.

2) IORING_SETUP_SQPOLL: same as with single issuer, only one task is
   a major user of ->uring_lock.

3) apoll: we normally grab the lock on the completion side anyway to
   execute the request, so it's free.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1bbad9c78c454b7b92f100bbf46730a37df7194f.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Instead of passing around a pointer to hash buckets, add a bit of type
safety and wrap it into a structure.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d65bc3faba537ec2aca9eabf334394936d44bd28.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a new IORING_SETUP_SINGLE_ISSUER flag and the userspace visible part
of it, i.e. put limitations of submitters. Also, don't allow it together
with IOPOLL as we're not going to put it to good use.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/4bcc41ee467fdf04c8aab8baf6ce3ba21858c3d4.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a variable for the number of hash buckets in io_ring_ctx_alloc(),
makes it more readable.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/993926ed0d614ba9a76b2a85bebae2babcb13983.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Don't allocate to many hash/cancellation buckets, there might be too
many, clamp it to 8 bits, or 256 * 64B = 16KB. We don't usually have too
many requests, and 256 buckets should be enough, especially since we
do hash search only in the cancellation path.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b9620c8072ba61a2d50eba894b89bd93a94a9abd.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a new io_hash_bucket structure so that each bucket in cancel_hash
has separate spinlock. Use per entry lock for cancel_hash, this removes
some completion lock invocation and remove contension between different
cancel_hash entries.
Signed-off-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/05d1e135b0c8bce9d1441e6346776589e5783e26.1655371007.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Clean up io_req_task_complete() and deduplicate io_put_kbuf() calls.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ae3148ac7eb5cce3e06895cde306e9e959d6f6ae.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

REQ_F_COMPLETE_INLINE is only needed to delay queueing into the
completion list to io_queue_sqe() as __io_req_complete() is inlined and
we don't want to bloat the kernel.

As now we complete in a more centralised fashion in io_issue_sqe() we
can get rid of the flag and queue to the list directly.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/600ba20a9338b8a39b249b23d3d177803613dde4.1655371007.git.asml.silence@gmail.comReviewed-by: NHao Xu <howeyxu@tencent.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

io_req_task_complete() enqueues requests for state completion itself, no
need for REQ_F_COMPLETE_INLINE, which is only serve the purpose of not
bloating the kernel.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/aca80f71464ad02c06f1311d998a2d6ee0b31573.1655310733.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

All ctx->check_cq events are slow path, don't test every single flag one
by one in the hot path, but add a common guarding if.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/dff026585cea7ff3a172a7c83894a3b0111bbf6a.1655310733.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

Luckily, nnobody completes multi-apoll requests outside the polling
functions, but don't set IO_URING_F_COMPLETE_DEFER in any case as
there is nobody who is catching REQ_F_COMPLETE_INLINE, and so will leak
requests if used.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a65ed3f5effd9321ee06e6edea294a03be3e15a0.1655310733.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

There is a bunch of inline helpers that will be useful not only to the
core of io_uring, move them to headers.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/22df99c83723e44cba7e945e8519e64e3642c064.1655310733.git.asml.silence@gmail.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

We already have the declarations in opdef.h, move the rest into its own
file rather than in the main io_uring.c file.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Move both the opcodes related to it, and the internals code dealing with
it.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This also helps cleanup the io_uring.h cancel parts, as we can make
things static in the cancel.c file, mostly.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add a io_poll_issue() rather than export the general task_work locking
and io_issue_sqe(), and put the io_op_defs definition and structure into
a separate header file so that poll can use it.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This kills the last per-op switch.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Remove some dead headers we no longer need, and get rid of the
io_ring_ctx and io_uring_fops forward declarations.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

This also means moving a bit more of the fixed file handling to the
filetable side, which makes sense separately too.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Convert the last spots that check for io_uring_fops to use the provided
helper instead.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

While at it, convert the handlers to just use io_eopnotsupp_prep()
if CONFIG_NET isn't set.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Would be nice to sort out Kconfig for this and don't even compile
epoll.c if we don't have epoll configured.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add it and use it for the epoll handling, if epoll isn't configured.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>

Signed-off-by: NJens Axboe <axboe@kernel.dk>