Commit graph

159 commits

Author SHA1 Message Date
Jens Axboe
3aa5fa0305 io_uring: kill dead REQ_F_LINK_DONE flag
We had no more use for this flag after the conversion to io-wq, kill it
off.

Fixes: 561fb04a6a ("io_uring: replace workqueue usage with io-wq")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-05 20:34:32 -07:00
Jens Axboe
f1f40853c0 io_uring: fixup a few spots where link failure isn't flagged
If a request fails, we need to ensure we set REQ_F_FAIL_LINK on it if
REQ_F_LINK is set. Any failure in the chain should break the chain.

We were missing a few spots where this should be done. It might be nice
to generalize this somewhat at some point, as long as we factor in the
fact that failure looks different for each request type.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-05 20:33:16 -07:00
Jens Axboe
89723d0bd6 io_uring: enable optimized link handling for IORING_OP_POLL_ADD
As introduced by commit:

ba816ad61f ("io_uring: run dependent links inline if possible")

enable inline dependent link running for poll commands.
io_poll_complete_work() is the most important change, as it allows a
linked sequence of { POLL, READ } (for example) to proceed inline
instead of needing to get punted to another async context. The
submission side only potentially matters for sqthread, but may as well
include that bit.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-05 15:32:58 -07:00
Jens Axboe
51c3ff62ca io_uring: add completion trace event
We currently don't have a completion event trace, add one of those. And
to better be able to match up submissions and completions, add user_data
to the submission trace as well.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-04 07:07:52 -07:00
Jackie Liu
e9ffa5c2b7 io_uring: set -EINTR directly when a signal wakes up in io_cqring_wait
We didn't use -ERESTARTSYS to tell the application layer to restart the
system call, but instead return -EINTR. we can set -EINTR directly when
wakeup by the signal, which can help us save an assignment operation and
comparison operation.

Reviewed-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-01 08:36:36 -06:00
Jens Axboe
62755e35df io_uring: support for generic async request cancel
This adds support for IORING_OP_ASYNC_CANCEL, which will attempt to
cancel requests that have been punted to async context and are now
in-flight. This works for regular read/write requests to files, as
long as they haven't been started yet. For socket based IO (or things
like accept4(2)), we can cancel work that is already running as well.

To cancel a request, the sqe must have ->addr set to the user_data of
the request it wishes to cancel. If the request is cancelled
successfully, the original request is completed with -ECANCELED
and the cancel request is completed with a result of 0. If the
request was already running, the original may or may not complete
in error. The cancel request will complete with -EALREADY for that
case. And finally, if the request to cancel wasn't found, the cancel
request is completed with -ENOENT.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-01 08:35:31 -06:00
Jens Axboe
975c99a570 io_uring: io_wq_create() returns an error pointer, not NULL
syzbot reported an issue where we crash at setup time if failslab is
used. The issue is that io_wq_create() returns an error pointer on
failure, not NULL. Hence io_uring thought the io-wq was setup just
fine, but in reality it's a garbage error pointer.

Use IS_ERR() instead of a NULL check, and assign ret appropriately.

Reported-by: syzbot+221cc24572a2fed23b6b@syzkaller.appspotmail.com
Fixes: 561fb04a6a ("io_uring: replace workqueue usage with io-wq")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-30 08:42:56 -06:00
Jens Axboe
842f96124c io_uring: fix race with canceling timeouts
If we get -1 from hrtimer_try_to_cancel(), we know that the timer
is running. Hence leave all completion to the timeout handler. If
we don't, we can corrupt the list and miss a completion.

Fixes: 11365043e5 ("io_uring: add support for canceling timeout requests")
Reported-by: Hrvoje Zeba <zeba.hrvoje@gmail.com>
Tested-by: Hrvoje Zeba <zeba.hrvoje@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 15:43:30 -06:00
Jens Axboe
65e19f54d2 io_uring: support for larger fixed file sets
There's been a few requests for supporting more fixed files than 1024.
This isn't really tricky to do, we just need to split up the file table
into multiple tables and index appropriately. As we do so, reduce the
max single file table to 512. This enables us to do single page allocs
always for the tables, which is an improvement over the situation prior.

This patch adds support for up to 64K files, which should be enough for
everyone.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 12:43:06 -06:00
Jens Axboe
b7620121dc io_uring: protect fixed file indexing with array_index_nospec()
We index the file tables with a user given value. After we check
it's within our limits, use array_index_nospec() to prevent any
spectre attacks here.

Suggested-by: Jann Horn <jannh@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 12:43:06 -06:00
Jens Axboe
17f2fe35d0 io_uring: add support for IORING_OP_ACCEPT
This allows an application to call accept4() in an async fashion. Like
other opcodes, we first try a non-blocking accept, then punt to async
context if we have to.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 12:43:06 -06:00
Jens Axboe
fcb323cc53 io_uring: io_uring: add support for async work inheriting files
This is in preparation for adding opcodes that need to add new files
in a process file table, system calls like open(2) or accept4(2).

If an opcode needs this, it must set IO_WQ_WORK_NEEDS_FILES in the work
item. If work that needs to get punted to async context have this
set, the async worker will assume the original task file table before
executing the work.

Note that opcodes that need access to the current files of an
application cannot be done through IORING_SETUP_SQPOLL.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 12:43:06 -06:00
Jens Axboe
561fb04a6a io_uring: replace workqueue usage with io-wq
Drop various work-arounds we have for workqueues:

- We no longer need the async_list for tracking sequential IO.

- We don't have to maintain our own mm tracking/setting.

- We don't need a separate workqueue for buffered writes. This didn't
  even work that well to begin with, as it was suboptimal for multiple
  buffered writers on multiple files.

- We can properly cancel pending interruptible work. This fixes
  deadlocks with particularly socket IO, where we cannot cancel them
  when the io_uring is closed. Hence the ring will wait forever for
  these requests to complete, which may never happen. This is different
  from disk IO where we know requests will complete in a finite amount
  of time.

- Due to being able to cancel work interruptible work that is already
  running, we can implement file table support for work. We need that
  for supporting system calls that add to a process file table.

- It gets us one step closer to adding async support for any system
  call.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 12:43:06 -06:00
Pavel Begunkov
95a1b3ff9a io_uring: Fix mm_fault with READ/WRITE_FIXED
Commit fb5ccc9878 ("io_uring: Fix broken links with offloading")
introduced a potential performance regression with unconditionally
taking mm even for READ/WRITE_FIXED operations.

Return the logic handling it back. mm-faulted requests will go through
the generic submission path, so honoring links and drains, but will
fail further on req->has_user check.

Fixes: fb5ccc9878 ("io_uring: Fix broken links with offloading")
Cc: stable@vger.kernel.org # v5.4
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:24:23 -06:00
Pavel Begunkov
fa45622808 io_uring: remove index from sqe_submit
submit->index is used only for inbound check in submission path (i.e.
head < ctx->sq_entries). However, it always will be true, as
1. it's already validated by io_get_sqring()
2. ctx->sq_entries can't be changedd in between, because of held
ctx->uring_lock and ctx->refs.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:24:21 -06:00
Dmitrii Dolgov
c826bd7a74 io_uring: add set of tracing events
To trace io_uring activity one can get an information from workqueue and
io trace events, but looks like some parts could be hard to identify via
this approach. Making what happens inside io_uring more transparent is
important to be able to reason about many aspects of it, hence introduce
the set of tracing events.

All such events could be roughly divided into two categories:

* those, that are helping to understand correctness (from both kernel
  and an application point of view). E.g. a ring creation, file
  registration, or waiting for available CQE. Proposed approach is to
  get a pointer to an original structure of interest (ring context, or
  request), and then find relevant events. io_uring_queue_async_work
  also exposes a pointer to work_struct, to be able to track down
  corresponding workqueue events.

* those, that provide performance related information. Mostly it's about
  events that change the flow of requests, e.g. whether an async work
  was queued, or delayed due to some dependencies. Another important
  case is how io_uring optimizations (e.g. registered files) are
  utilized.

Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:24:18 -06:00
Jens Axboe
11365043e5 io_uring: add support for canceling timeout requests
We might have cases where the need for a specific timeout is gone, add
support for canceling an existing timeout operation. This works like the
POLL_REMOVE command, where the application passes in the user_data of
the timeout it wishes to cancel in the sqe->addr field.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:50 -06:00
Jens Axboe
a41525ab2e io_uring: add support for absolute timeouts
This is a pretty trivial addition on top of the relative timeouts
we have now, but it's handy for ensuring tighter timing for those
that are building scheduling primitives on top of io_uring.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:48 -06:00
Jackie Liu
ba5290ccb6 io_uring: replace s->needs_lock with s->in_async
There is no function change, just to clean up the code, use s->in_async
to make the code know where it is.

Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:47 -06:00
Jens Axboe
33a107f0a1 io_uring: allow application controlled CQ ring size
We currently size the CQ ring as twice the SQ ring, to allow some
flexibility in not overflowing the CQ ring. This is done because the
SQE life time is different than that of the IO request itself, the SQE
is consumed as soon as the kernel has seen the entry.

Certain application don't need a huge SQ ring size, since they just
submit IO in batches. But they may have a lot of requests pending, and
hence need a big CQ ring to hold them all. By allowing the application
to control the CQ ring size multiplier, we can cater to those
applications more efficiently.

If an application wants to define its own CQ ring size, it must set
IORING_SETUP_CQSIZE in the setup flags, and fill out
io_uring_params->cq_entries. The value must be a power of two.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:46 -06:00
Jens Axboe
c3a31e6056 io_uring: add support for IORING_REGISTER_FILES_UPDATE
Allows the application to remove/replace/add files to/from a file set.
Passes in a struct:

struct io_uring_files_update {
	__u32 offset;
	__s32 *fds;
};

that holds an array of fds, size of array passed in through the usual
nr_args part of the io_uring_register() system call. The logic is as
follows:

1) If ->fds[i] is -1, the existing file at i + ->offset is removed from
   the set.
2) If ->fds[i] is a valid fd, the existing file at i + ->offset is
   replaced with ->fds[i].

For case #2, is the existing file is currently empty (fd == -1), the
new fd is simply added to the array.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:44 -06:00
Jens Axboe
08a451739a io_uring: allow sparse fixed file sets
This is in preparation for allowing updates to fixed file sets without
requiring a full unregister+register.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:43 -06:00
Jens Axboe
ba816ad61f io_uring: run dependent links inline if possible
Currently any dependent link is executed from a new workqueue context,
which means that we'll be doing a context switch per link in the chain.
If we are running the completion of the current request from our async
workqueue and find that the next request is a link, then run it directly
from the workqueue context instead of forcing another switch.

This improves the performance of linked SQEs, and reduces the CPU
overhead.

Reviewed-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-29 10:22:41 -06:00
Jens Axboe
044c1ab399 io_uring: don't touch ctx in setup after ring fd install
syzkaller reported an issue where it looks like a malicious app can
trigger a use-after-free of reading the ctx ->sq_array and ->rings
value right after having installed the ring fd in the process file
table.

Defer ring fd installation until after we're done reading those
values.

Fixes: 75b28affdd ("io_uring: allocate the two rings together")
Reported-by: syzbot+6f03d895a6cd0d06187f@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-28 09:15:33 -06:00
Pavel Begunkov
7b20238d28 io_uring: Fix leaked shadow_req
io_queue_link_head() owns shadow_req after taking it as an argument.
By not freeing it in case of an error, it can leak the request along
with taken ctx->refs.

Reviewed-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-27 21:29:18 -06:00
Jens Axboe
2b2ed9750f io_uring: fix bad inflight accounting for SETUP_IOPOLL|SETUP_SQTHREAD
We currently assume that submissions from the sqthread are successful,
and if IO polling is enabled, we use that value for knowing how many
completions to look for. But if we overflowed the CQ ring or some
requests simply got errored and already completed, they won't be
available for polling.

For the case of IO polling and SQTHREAD usage, look at the pending
poll list. If it ever hits empty then we know that we don't have
anymore pollable requests inflight. For that case, simply reset
the inflight count to zero.

Reported-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 10:58:53 -06:00
Jens Axboe
498ccd9eda io_uring: used cached copies of sq->dropped and cq->overflow
We currently use the ring values directly, but that can lead to issues
if the application is malicious and changes these values on our behalf.
Created in-kernel cached versions of them, and just overwrite the user
side when we update them. This is similar to how we treat the sq/cq
ring tail/head updates.

Reported-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 10:58:45 -06:00
Pavel Begunkov
935d1e4590 io_uring: Fix race for sqes with userspace
io_ring_submit() finalises with
1. io_commit_sqring(), which releases sqes to the userspace
2. Then calls to io_queue_link_head(), accessing released head's sqe

Reorder them.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 09:02:01 -06:00
Pavel Begunkov
fb5ccc9878 io_uring: Fix broken links with offloading
io_sq_thread() processes sqes by 8 without considering links. As a
result, links will be randomely subdivided.

The easiest way to fix it is to call io_get_sqring() inside
io_submit_sqes() as do io_ring_submit().

Downsides:
1. This removes optimisation of not grabbing mm_struct for fixed files
2. It submitting all sqes in one go, without finer-grained sheduling
with cq processing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 09:01:59 -06:00
Pavel Begunkov
84d55dc5b9 io_uring: Fix corrupted user_data
There is a bug, where failed linked requests are returned not with
specified @user_data, but with garbage from a kernel stack.

The reason is that io_fail_links() uses req->user_data, which is
uninitialised when called from io_queue_sqe() on fail path.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-25 09:01:58 -06:00
zhangyi (F)
a1f58ba46f io_uring: correct timeout req sequence when inserting a new entry
The sequence number of the timeout req (req->sequence) indicate the
expected completion request. Because of each timeout req consume a
sequence number, so the sequence of each timeout req on the timeout
list shouldn't be the same. But now, we may get the same number (also
incorrect) if we insert a new entry before the last one, such as submit
such two timeout reqs on a new ring instance below.

                    req->sequence
 req_1 (count = 2):       2
 req_2 (count = 1):       2

Then, if we submit a nop req, req_2 will still timeout even the nop req
finished. This patch fix this problem by adjust the sequence number of
each reordered reqs when inserting a new entry.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-23 22:09:56 -06:00
zhangyi (F)
ef03681ae8 io_uring : correct timeout req sequence when waiting timeout
The sequence number of reqs on the timeout_list before the timeout req
should be adjusted in io_timeout_fn(), because the current timeout req
will consumes a slot in the cq_ring and cq_tail pointer will be
increased, otherwise other timeout reqs may return in advance without
waiting for enough wait_nr.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-23 22:09:56 -06:00
Jens Axboe
bc808bced3 io_uring: revert "io_uring: optimize submit_and_wait API"
There are cases where it isn't always safe to block for submission,
even if the caller asked to wait for events as well. Revert the
previous optimization of doing that.

This reverts two commits:

bf7ec93c64
c576666863

Fixes: c576666863 ("io_uring: optimize submit_and_wait API")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-23 22:09:56 -06:00
Linus Torvalds
d418d07005 for-linus-2019-10-18
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2qbF0QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgptsuEADEKL8pta74uy50pl0t8l9fZ++U+wdIeEIW
 9uumpOEPnI2GpkG1sOyKWK6tl8InQLw6pAquP9MoT2BHXqFHk7NIgtvk67lwQeoc
 dRwklVfvOLAdnKzyfODqE9Fh9BgczZIuOLzgdtNqrPKqgJfFRCwN94Kj/r2tYuy7
 v+riK3A49u12dOLtjU6ciNgZ0m1iUX9s0+PFYVUXtJHU/1OYToQaKP+sgWiue0Ca
 VJP/L4MLYD0a7tfd92WAK7xWLsYWTDw1Gg20hXH/tV+IIDQ5+OXhu2s6PuqI7c0y
 cZqWHQHBDkZMQvT8+V+YqZtEa+xwVCom51prJEPasmdq3fGx+2sDC1HQiySao1ML
 wfFxZvFvY9fm6M7p2xsSNEcOmamrx1aLLyNSbjIvAqLUDYJWWS56BHsKyTU5Z+Jp
 RA9dpq8iR6ISaIAcFf0IB0pJSv1HEeHyo/ixlALqezBFJaMdhWy/M+dEbWKtix9M
 s19ozcpe+omN9+O0anlLtzKNgj2Xnjiwuu8mhVcqn6uG/p6GUOup+lNvTW/fig3I
 JBH8kObjYXL181V9rYVqFutnuqcf2HYqMvV2vzAmg4LYnPVUmU7HMj8zEpxc4N+f
 Evd77j0wXmY9S+4JERxaqQZuvKBEIkvM1rkk3N4NbNghfa7QL4aW+I9cWtuelPC2
 E+DK7if0Gg==
 =rvkw
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-2019-10-18' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - NVMe pull request from Keith that address deadlocks, double resets,
   memory leaks, and other regression.

 - Fixup elv_support_iosched() for bio based devices (Damien)

 - Fixup for the ahci PCS quirk (Dan)

 - Socket O_NONBLOCK handling fix for io_uring (me)

 - Timeout sequence io_uring fixes (yangerkun)

 - MD warning fix for parameter default_layout (Song)

 - blkcg activation fixes (Tejun)

 - blk-rq-qos node deletion fix (Tejun)

* tag 'for-linus-2019-10-18' of git://git.kernel.dk/linux-block:
  nvme-pci: Set the prp2 correctly when using more than 4k page
  io_uring: fix logic error in io_timeout
  io_uring: fix up O_NONBLOCK handling for sockets
  md/raid0: fix warning message for parameter default_layout
  libata/ahci: Fix PCS quirk application
  blk-rq-qos: fix first node deletion of rq_qos_del()
  blkcg: Fix multiple bugs in blkcg_activate_policy()
  io_uring: consider the overflow of sequence for timeout req
  nvme-tcp: fix possible leakage during error flow
  nvmet-loop: fix possible leakage during error flow
  block: Fix elv_support_iosched()
  nvme-tcp: Initialize sk->sk_ll_usec only with NET_RX_BUSY_POLL
  nvme: Wait for reset state when required
  nvme: Prevent resets during paused controller state
  nvme: Restart request timers in resetting state
  nvme: Remove ADMIN_ONLY state
  nvme-pci: Free tagset if no IO queues
  nvme: retain split access workaround for capability reads
  nvme: fix possible deadlock when nvme_update_formats fails
2019-10-18 22:29:36 -04:00
yangerkun
8b07a65ad3 io_uring: fix logic error in io_timeout
If ctx->cached_sq_head < nxt_sq_head, we should add UINT_MAX to tmp, not
tmp_nxt.

Fixes: 5da0fb1ab3 ("io_uring: consider the overflow of sequence for timeout req")
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-17 15:49:15 -06:00
Jens Axboe
491381ce07 io_uring: fix up O_NONBLOCK handling for sockets
We've got two issues with the non-regular file handling for non-blocking
IO:

1) We don't want to re-do a short read in full for a non-regular file,
   as we can't just read the data again.
2) For non-regular files that don't support non-blocking IO attempts,
   we need to punt to async context even if the file is opened as
   non-blocking. Otherwise the caller always gets -EAGAIN.

Add two new request flags to handle these cases. One is just a cache
of the inode S_ISREG() status, the other tells io_uring that we always
need to punt this request to async context, even if REQ_F_NOWAIT is set.

Cc: stable@vger.kernel.org
Reported-by: Hrvoje Zeba <zeba.hrvoje@gmail.com>
Tested-by: Hrvoje Zeba <zeba.hrvoje@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-17 15:49:11 -06:00
yangerkun
5da0fb1ab3 io_uring: consider the overflow of sequence for timeout req
Now we recalculate the sequence of timeout with 'req->sequence =
ctx->cached_sq_head + count - 1', judge the right place to insert
for timeout_list by compare the number of request we still expected for
completion. But we have not consider about the situation of overflow:

1. ctx->cached_sq_head + count - 1 may overflow. And a bigger count for
the new timeout req can have a small req->sequence.

2. cached_sq_head of now may overflow compare with before req. And it
will lead the timeout req with small req->sequence.

This overflow will lead to the misorder of timeout_list, which can lead
to the wrong order of the completion of timeout_list. Fix it by reuse
req->submit.sequence to store the count, and change the logic of
inserting sort in io_timeout.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-15 08:55:50 -06:00
Linus Torvalds
b27528b027 for-linus-20191012
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2iBvAQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpvokEACaUozc0Y2L99CqJcRtoH8cwIAimjKTFSmi
 UKijO/w11uc9xCIOospkM8iseRbpP/oCIwfYyVROi4LniPB1TSyQJoLF/MELeqIi
 lOSg8RrXzC22h5+QG3BR5VO55me3MwIXmJLMMWXbh7FAuUg+wepVwHwzZBurd1Pz
 C1wG8NU758AmqJdSGclUbdLLwTBkR+fXoi2EHfdbsBMqGmdZ5VRzCLx70grDcxq2
 S9gt+2+diME6o6p1wko+m9pdhUdEy7epPE50K4SA+DU06I77OZpTdSAPilPyQHei
 +3HDslzjCyos5/Ay+7hWl42jvyZ+x6GI5VcDLMTcMZsmxLy/WObDB4zcAixJrDV0
 c7XWnwCCs2wMXYMsu0ASbkU32mcQ/Ik8CrX0W3/tP1aZBW2LZnOHvXYbybzpbgbo
 QY47t3jz21uzF5kplBGxqaY1sPmLxp5V0vQmj9eN+Y7T+hiR/UgWKO/5B4CGNJe0
 BQkXNl5cZAtqxmSE8AxlpOla7z6beZUljdhFc7K8cMDdhoatRgm2MBh2G9BB1ayo
 VwHc1qLcvInpQrGiC4l5H/F8jrEs/PglknFSs1wlsav1gXA69J0cHA7LY6Czweaw
 mkiKr7jA6duBBn6MRUThF5sBMFWYuxp3B/BA4wfDJsSfCmyhWN+OZlsDaEVrzk7o
 /XK2Ew9R2Q==
 =PUeL
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-20191012' of git://git.kernel.dk/linux-block

Pull io_uring fix from Jens Axboe:
 "Single small fix for a regression in the sequence logic for linked
  commands"

* tag 'for-linus-20191012' of git://git.kernel.dk/linux-block:
  io_uring: fix sequence logic for timeout requests
2019-10-13 08:15:35 -07:00
Linus Torvalds
297cbcccc2 for-linus-20191010
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2f5MIQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpvscD/4v8E1s1rt6JwqM0Fa27UjRdhfGnc8ad8vs
 fD7rf3ZmLkoM1apVopMcAscUH726wU4qbxwEUDEntxxv2wJHuZdSZ64zhFJ17uis
 uJ2pF4MpK/m6DnHZu/SAU4t9aU+l6SBqX0tS1bFycecPgGRk46jrVX5tNJggt0Fy
 hqmx3ACWbkGiFDERT2AAQ69WHfmzeI9aUjx3jJY2eLnK7OjjEpyoEBs0j/AHl3ep
 kydhItU5NSFCv94X7vmZy/dvQ5hE4/1HTFfg79fOZcywQi1AN5DafKxiM2kgaSJ0
 jW58i+AFVtUPysNpVsxvjAgqGwDX/UJkOkggPd6V8/6LMfEvBKY4YNXlUEbqTN3Y
 pqn19/cgdKHaQpHKqwettcQujc71kry/yHsaudD+g2fi0efYi3d4qxIp9XA0TF03
 z6jzp8Hfo2SKbwapIFPa7Wqj86ZpbBxtROibCA17WKSNzn0UR3pJmEigo4l364ow
 nJpvZChLDHZXjovgzISmUnbR+O1yP0+ZnI9b7kgNp0UV4SI5ajf6f2T7667dcQs0
 J1GNt4QvqPza3R0z1SuoEi6tbc3GyMj7NZyIseNOXR/NtqXEWtiNvDIuZqs6Wn/T
 4GhaF0Mjqc17B3UEkdU1z09HL0JR40vUrGYE4lDxHhPWd0YngDGJJX2pZG2Y0WBp
 VQ20AzijzQ==
 =wZnt
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-20191010' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Fix wbt performance regression introduced with the blk-rq-qos
   refactoring (Harshad)

 - Fix io_uring fileset removal inadvertently killing the workqueue (me)

 - Fix io_uring typo in linked command nonblock submission (Pavel)

 - Remove spurious io_uring wakeups on request free (Pavel)

 - Fix null_blk zoned command error return (Keith)

 - Don't use freezable workqueues for backing_dev, also means we can
   revert a previous libata hack (Mika)

 - Fix nbd sysfs mutex dropped too soon at removal time (Xiubo)

* tag 'for-linus-20191010' of git://git.kernel.dk/linux-block:
  nbd: fix possible sysfs duplicate warning
  null_blk: Fix zoned command return code
  io_uring: only flush workqueues on fileset removal
  io_uring: remove wait loop spurious wakeups
  blk-wbt: fix performance regression in wbt scale_up/scale_down
  Revert "libata, freezer: avoid block device removal while system is frozen"
  bdi: Do not use freezable workqueue
  io_uring: fix reversed nonblock flag for link submission
2019-10-11 08:45:32 -07:00
Jens Axboe
7adf4eaf60 io_uring: fix sequence logic for timeout requests
We have two ways a request can be deferred:

1) It's a regular request that depends on another one
2) It's a timeout that tracks completions

We have a shared helper to determine whether to defer, and that
attempts to make the right decision based on the request. But we
only have some of this information in the caller. Un-share the
two timeout/defer helpers so the caller can use the right one.

Fixes: 5262f56798 ("io_uring: IORING_OP_TIMEOUT support")
Reported-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-10 21:42:58 -06:00
Jens Axboe
8a99734081 io_uring: only flush workqueues on fileset removal
We should not remove the workqueue, we just need to ensure that the
workqueues are synced. The workqueues are torn down on ctx removal.

Cc: stable@vger.kernel.org
Fixes: 6b06314c47 ("io_uring: add file set registration")
Reported-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-09 15:13:47 -06:00
Pavel Begunkov
6805b32ec2 io_uring: remove wait loop spurious wakeups
Any changes interesting to tasks waiting in io_cqring_wait() are
commited with io_cqring_ev_posted(). However, io_ring_drop_ctx_refs()
also tries to do that but with no reason, that means spurious wakeups
every io_free_req() and io_uring_enter().

Just use percpu_ref_put() instead.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-07 21:16:24 -06:00
Linus Torvalds
c4bd70e8c9 for-linus-2019-10-03
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2WrkYQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpjf1D/9wy2L/yAXA/KLQkwDZ2kn3tMtzMrsv6bOJ
 4UTdlLWKH2ihGg69iAE5f19iQSeNmqqXxBz0VvIBpFR7TqcRbGe0d9iVtoOsDhpZ
 c1OvQ2Ey35Xx1T2w6uMh0llgeWY2J/gJkY64unUxwUBUZwNOPA8ZjxqeXcMQmyAt
 sYmXpNLCT/f4YTYOYDgzoh5960TsCB/H+m/bLEVRvr0MaonvlaBUKRcysQikDFCQ
 yobzDmlSJqGKqlFJ2fnRVSkJC0BmBE5p8Ric9HHiUOT8BO31079IHUGbkbSh/csH
 0yPipNaYNMv+Hr0t9pgfcNbAt2weMK5HFgtpQwv8Frl4xjvBSWDS5fQesCVDjkZt
 +ROeOvQtjfeKtLy5PCu6BJwYpu8iYG9eGF8zxBQ4FBHM3tghcVhqssaNbfrVOW+u
 YXYbAuLMkLwKlmJ+6WBiVIMefyF59ue3+UJGECiCrj/BrgxUyw8HcGKwpKEAZSok
 VFGDukL0Y3flnoO/gyOf0GFaD5Uovr1sx82DCz05B/XEMfkqFMJRGkbyZBarJL69
 9QrnyGpF4rwtfg+usR1PmJ+9/oY/ypSk8N9MAIkoK9e1YIexxvBiXAf0k8AxuDyC
 uPuOiQgKcqUr3aF+ivao8dQB9NiK1bJGc4pqBPPN4ZYRSjMSfBT/cms4IeUyj0K6
 sokcB1p+CQ==
 =vKVl
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-2019-10-03' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Mandate timespec64 for the io_uring timeout ABI (Arnd)

 - Set of NVMe changes via Sagi:
     - controller removal race fix from Balbir
     - quirk additions from Gabriel and Jian-Hong
     - nvme-pci power state save fix from Mario
     - Add 64bit user commands (for 64bit registers) from Marta
     - nvme-rdma/nvme-tcp fixes from Max, Mark and Me
     - Minor cleanups and nits from James, Dan and John

 - Two s390 dasd fixes (Jan, Stefan)

 - Have loop change block size in DIO mode (Martijn)

 - paride pg header ifdef guard (Masahiro)

 - Two blk-mq queue scheduler tweaks, fixing an ordering issue on zoned
   devices and suboptimal performance on others (Ming)

* tag 'for-linus-2019-10-03' of git://git.kernel.dk/linux-block: (22 commits)
  block: sed-opal: fix sparse warning: convert __be64 data
  block: sed-opal: fix sparse warning: obsolete array init.
  block: pg: add header include guard
  Revert "s390/dasd: Add discard support for ESE volumes"
  s390/dasd: Fix error handling during online processing
  io_uring: use __kernel_timespec in timeout ABI
  loop: change queue block size to match when using DIO
  blk-mq: apply normal plugging for HDD
  blk-mq: honor IO scheduler for multiqueue devices
  nvme-rdma: fix possible use-after-free in connect timeout
  nvme: Move ctrl sqsize to generic space
  nvme: Add ctrl attributes for queue_count and sqsize
  nvme: allow 64-bit results in passthru commands
  nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T
  nvmet-tcp: remove superflous check on request sgl
  Added QUIRKs for ADATA XPG SX8200 Pro 512GB
  nvme-rdma: Fix max_hw_sectors calculation
  nvme: fix an error code in nvme_init_subsystem()
  nvme-pci: Save PCI state before putting drive into deepest state
  nvme-tcp: fix wrong stop condition in io_work
  ...
2019-10-04 09:56:51 -07:00
Pavel Begunkov
bf7ec93c64 io_uring: fix reversed nonblock flag for link submission
io_queue_link_head() accepts @force_nonblock flag, but io_ring_submit()
passes something opposite.

Fixes: c576666863 ("io_uring: optimize submit_and_wait API")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-04 08:31:15 -06:00
Arnd Bergmann
bdf2007311 io_uring: use __kernel_timespec in timeout ABI
All system calls use struct __kernel_timespec instead of the old struct
timespec, but this one was just added with the old-style ABI. Change it
now to enforce the use of __kernel_timespec, avoiding ABI confusion and
the need for compat handlers on 32-bit architectures.

Any user space caller will have to use __kernel_timespec now, but this
is unambiguous and works for any C library regardless of the time_t
definition. A nicer way to specify the timeout would have been a less
ambiguous 64-bit nanosecond value, but I suppose it's too late now to
change that as this would impact both 32-bit and 64-bit users.

Fixes: 5262f56798 ("io_uring: IORING_OP_TIMEOUT support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-01 09:53:29 -06:00
Linus Torvalds
738f531d87 for-5.4/io_uring-2019-09-27
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2OIu4QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpsedD/4h54330vuq66DsGqzFLonLwFl5YHC5NeJX
 aV38j7pAUPHvr9CSnr3d2VwTk/ThBtPI50I9/d9SXh8n1oAAA5C/+nPf1XknME47
 giKHr3eb0FNLOySt/Ry284gla8mO0GZM83zUbDMnF0N+tfwAtFvbvgCpsPFK9vdL
 xNzMLsq6++pj7p9c6IXd+zv0nmJzDikZQz6PtU1KYlbfnU7hh/cP3CrIHIPtGbyk
 c/7tfbKTB9UnbW5guGakZt3BzNViJpK28SKn+S6AlLiEOYpC+55dBbaZQIy5qxHv
 CZsx0GJIw0Ya0Lw3UEFp/74krLHq2610jmx/va8P7MZCjZAR675G3mjxKUnC/+SY
 mEdLo6vghMNAIqMBWNu59CFQOPnqa8sqRii0q6cRWXSqKiFr1FLN8mstb3Ghh9K0
 kGVA/gw6ESWB/e/X6I+pD6pTm6O6BPWEqBzGAWSvavQQIP9YpIzf5j+k3JsRu03/
 IIzR6gW9k9u4k0rFlOJKbp1+AO5sK3VtJFR8JGELiRwwgjD91w50gjPYak5OGM37
 Mi7OHCxqtwFGTkSvT6RM6om6onBsizrveszkrPUO01bWYIHHbtu6ofLyQlfnEtpv
 qbGZtLW6KYj9VsIKZNDfg99Ff79IAOiAZDbXWAu/JKyg/gu1Y9uOiVkNFPJGPNHV
 8ourcldMGg==
 =DEYH
 -----END PGP SIGNATURE-----

Merge tag 'for-5.4/io_uring-2019-09-27' of git://git.kernel.dk/linux-block

Pull more io_uring updates from Jens Axboe:
 "Just two things in here:

   - Improvement to the io_uring CQ ring wakeup for batched IO (me)

   - Fix wrong comparison in poll handling (yangerkun)

  I realize the first one is a little late in the game, but it felt
  pointless to hold it off until the next release. Went through various
  testing and reviews with Pavel and peterz"

* tag 'for-5.4/io_uring-2019-09-27' of git://git.kernel.dk/linux-block:
  io_uring: make CQ ring wakeups be more efficient
  io_uring: compare cached_cq_tail with cq.head in_io_uring_poll
2019-09-27 12:08:24 -07:00
Jens Axboe
bda521624e io_uring: make CQ ring wakeups be more efficient
For batched IO, it's not uncommon for waiters to ask for more than 1
IO to complete before being woken up. This is a problem with
wait_event() since tasks will get woken for every IO that completes,
re-check condition, then go back to sleep. For batch counts on the
order of what you do for high IOPS, that can result in 10s of extra
wakeups for the waiting task.

Add a private wake function that checks for the wake up count criteria
being met before calling autoremove_wake_function(). Pavel reports that
one test case he has runs 40% faster with proper batching of wakeups.

Reported-by: Pavel Begunkov <asml.silence@gmail.com>
Tested-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-26 03:55:40 -06:00
Linus Torvalds
b6cb84b4fc for-5.4/io_uring-2019-09-24
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl2J9DEQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpqiqD/9D9etX/wXJ54bNKXpQqba3tUQy8e5SLnd4
 q1ZzlJhvnmfNz6GqdH/1c+5Q2WBTLEb8PLJ4Z8d+1I8eWxpaCOzz362a7NA7x4l2
 d1a8MV8gQy0moJKX7kTL9Pn44d2HofxyhgmHFKkvm/j7P4HIKbAuckzlcGoOS9TS
 gV/bnroZ8eSrAfmswRRrxaWIoCe0iB+4x+nvoQjdVz8WXHcpBD8Y7hi5Ulid3Q/7
 vU4WJubwKrP1dczk1L64CnYN4QfP2k4pyyxQwEBujueNuAxPKTRD3GXQc58c63Bp
 GElE7FGxMUT4JhaY7U8G2pUSdAb2WiyMc9vd4Au7IkX0TEdQeRSHWkocnt2O9OPp
 nk7XqPNK5MSskE4T9fjsJkE4KiOHhslixxc5qY6X9g5GuPw03ITM4VBwvU8aYxbf
 p++jcWff10ovllck3uKvMpzU1IS20B4mSYYTyj990diocceEN6nsJsYv9wW4lMpk
 lBL8b/Q3TaoMG58C5BiZvlf6JQqdKpN5UJhBmyrZAv5ozvgBAcSeLK41V6oxzGzo
 y/3qcJeuIE6Exdm4DqWBHp7L82FcednO/EDqz3WnGx9v67kUz5VFqP7lIGNmXKM3
 2PaBMWv7BU/Fx087KOsBOI5XWm3aVw+yTkHT2aitVQW0su+UDvb/BvFL0sqbBe3O
 qm60F3TWkQ==
 =/w5G
 -----END PGP SIGNATURE-----

Merge tag 'for-5.4/io_uring-2019-09-24' of git://git.kernel.dk/linux-block

Pull more io_uring updates from Jens Axboe:
 "A collection of later fixes and additions, that weren't quite ready
  for pushing out with the initial pull request.

  This contains:

   - Fix potential use-after-free of shadow requests (Jackie)

   - Fix potential OOM crash in request allocation (Jackie)

   - kmalloc+memcpy -> kmemdup cleanup (Jackie)

   - Fix poll crash regression (me)

   - Fix SQ thread not being nice and giving up CPU for !PREEMPT (me)

   - Add support for timeouts, making it easier to do epoll_wait()
     conversions, for instance (me)

   - Ensure io_uring works without f_ops->read_iter() and
     f_ops->write_iter() (me)"

* tag 'for-5.4/io_uring-2019-09-24' of git://git.kernel.dk/linux-block:
  io_uring: correctly handle non ->{read,write}_iter() file_operations
  io_uring: IORING_OP_TIMEOUT support
  io_uring: use cond_resched() in sqthread
  io_uring: fix potential crash issue due to io_get_req failure
  io_uring: ensure poll commands clear ->sqe
  io_uring: fix use-after-free of shadow_req
  io_uring: use kmemdup instead of kmalloc and memcpy
2019-09-24 16:40:21 -07:00
Matthew Wilcox (Oracle)
a50b854e07 mm: introduce page_size()
Patch series "Make working with compound pages easier", v2.

These three patches add three helpers and convert the appropriate
places to use them.

This patch (of 3):

It's unnecessarily hard to find out the size of a potentially huge page.
Replace 'PAGE_SIZE << compound_order(page)' with page_size(page).

Link: http://lkml.kernel.org/r/20190721104612.19120-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:08 -07:00
yangerkun
daa5de5415 io_uring: compare cached_cq_tail with cq.head in_io_uring_poll
After 75b28af("io_uring: allocate the two rings together"), we compare
sq.head with cached_cq_tail to determine does there any cq invalid.
Actually, we should use cq.head.

Fixes: 75b28affdd ("io_uring: allocate the two rings together")
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-09-24 07:04:15 -06:00