Commit Graph

998288 Commits

Author SHA1 Message Date
Stefan Metzmacher
a2a7cc32a5 io_uring: io_sq_thread() no longer needs to reset current->pf_io_worker
This is done by create_io_thread() now.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:29:05 -06:00
Stefan Metzmacher
ff24430330 kernel: always initialize task->pf_io_worker to NULL
Otherwise io_wq_worker_{running,sleeping}() may dereference an
invalid pointer (in future). Currently all users of create_io_thread()
are fine and get task->pf_io_worker = NULL implicitly from the
wq_manager, which got it either from the userspace thread
of the sq_thread, which explicitly reset it to NULL.

I think it's safer to always reset it in order to avoid future
problems.

Fixes: 3bfe610669 ("io-wq: fork worker threads from original task")
cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:29:03 -06:00
Hao Xu
2b4ae19c6d io_uring: update sq_thread_idle after ctx deleted
we shall update sq_thread_idle anytime we do ctx deletion from ctx_list

Fixes:734551df6f9b ("io_uring: fix shared sqpoll cancellation hangs")

Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/1619256380-236460-1-git-send-email-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:25 -06:00
Pavel Begunkov
634d00df5e io_uring: add full-fledged dynamic buffers support
Hook buffers into all rsrc infrastructure, including tagging and
updates.

Suggested-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/119ed51d68a491dae87eb55fb467a47870c86aad.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Bijan Mottahedeh
bd54b6fe33 io_uring: implement fixed buffers registration similar to fixed files
Apply fixed_rsrc functionality for fixed buffers support.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
[rebase, remove multi-level tables, fix unregister on exit]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/17035f4f75319dc92962fce4fc04bc0afb5a68dc.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
eae071c9b4 io_uring: prepare fixed rw for dynanic buffers
With dynamic buffer updates, registered buffers in the table may change
at any moment. First of all we want to prevent future races between
updating and importing (i.e. io_import_fixed()), where the latter one
may happen without uring_lock held, e.g. from io-wq.

Save the first loaded io_mapped_ubuf buffer and reuse.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/21a2302d07766ae956640b6f753292c45200fe8f.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
41edf1a5ec io_uring: keep table of pointers to ubufs
Instead of keeping a table of ubufs convert them into pointers to ubuf,
so we can atomically read one pointer and be sure that the content of
ubuf won't change.

Because it was already dynamically allocating imu->bvec, throw both
imu and bvec into a single structure so they can be allocated together.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b96efa4c5febadeccf41d0e849ac099f4c83b0d3.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
c3bdad0271 io_uring: add generic rsrc update with tags
Add IORING_REGISTER_RSRC_UPDATE, which also supports passing in rsrc
tags. Implement it for registered files.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d4dc66df204212f64835ffca2c4eb5e8363f2f05.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
792e35824b io_uring: add IORING_REGISTER_RSRC
Add a new io_uring_register() opcode for rsrc registeration. Instead of
accepting a pointer to resources, fds or iovecs, it @arg is now pointing
to a struct io_uring_rsrc_register, and the second argument tells how
large that struct is to make it easily extendible by adding new fields.

All that is done mainly to be able to pass in a pointer with tags. Pass
it in and enable CQE posting for file resources. Doesn't support setting
tags on update yet.

A design choice made here is to not post CQEs on rsrc de-registration,
but only when we updated-removed it by rsrc dynamic update.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c498aaec32a4bb277b2406b9069662c02cdda98c.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
fdecb66281 io_uring: enumerate dynamic resources
As resources are getting more support and common parts, it'll be more
convenient to index resources and use it for indexing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f0be63e9310212d5601d36277c2946ff7a040485.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
98f0b3b4f1 io_uring: add generic path for rsrc update
Extract some common parts for rsrc update, will be used reg buffers
support dynamic (i.e. quiesce-lee) managing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b49c3ff6b9ff0e530295767604fe4de64d349e04.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
b60c8dce33 io_uring: preparation for rsrc tagging
We need a way to notify userspace when a lazily removed resource
actually died out. This will be done by associating a tag, which is u64
exactly like req->user_data, with each rsrc (e.g. buffer of file). A CQE
will be posted once a resource is actually put down.

Tag 0 is a special value set by default, for whcih it don't generate an
CQE, so providing the old behaviour.

Don't expose it to the userspace yet, but prepare internally, allocate
buffers, add all posting hooks, etc.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/2e6beec5eabe7216bb61fb93cdf5aaf65812a9b0.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
d4d19c19d6 io_uring: decouple CQE filling from requests
Make __io_cqring_fill_event() agnostic of struct io_kiocb, pass all the
data needed directly into it. Will be used to post rsrc removal
completions, which don't have an associated request.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c9b8da9e42772db2033547dfebe479dc972a0f2c.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
44b31f2fa2 io_uring: return back rsrc data free helper
Add io_rsrc_data_free() helper for destroying rsrc_data, easier for
search and the function will get more stuff to destroy shortly.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/562d1d53b5ff184f15b8949a63d76ef19c4ba9ec.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Pavel Begunkov
fff4db76be io_uring: move __io_sqe_files_unregister
A preparation patch moving __io_sqe_files_unregister() definition closer
to other "files" functions without any modification.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/95caf17fe837e67bd1f878395f07049062a010d4.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-25 10:14:04 -06:00
Hao Xu
724cb4f9ec io_uring: check sqring and iopoll_list before shedule
do this to avoid race below:

         userspace                         kernel

                               |  check sqring and iopoll_list
submit sqe                     |
check IORING_SQ_NEED_WAKEUP    |
(which is not set)    |        |
                               |  set IORING_SQ_NEED_WAKEUP
wait cqe                       |  schedule(never wakeup again)

Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Link: https://lore.kernel.org/r/1619018351-75883-1-git-send-email-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-23 08:26:41 -06:00
Pavel Begunkov
f2a48dd09b io_uring: refactor io_sq_offload_create()
Just a bit of code tossing in io_sq_offload_create(), so it looks a bit
better. No functional changes.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/939776f90de8d2cdd0414e1baa29c8ec0926b561.1618916549.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 12:55:28 -06:00
Pavel Begunkov
07db298a1c io_uring: safer sq_creds putting
Put sq_creds as a part of io_ring_ctx_free(), it's easy to miss doing it
in io_sq_thread_finish(), especially considering past mistakes related
to ring creation failures.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3becb1866467a1de82a97345a0a90d7fb8ff875e.1618916549.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 12:55:28 -06:00
Pavel Begunkov
3a0a690235 io_uring: move inflight un-tracking into cleanup
REQ_F_INFLIGHT deaccounting doesn't do any spinlocking or resource
freeing anymore, so it's safe to move it into the normal cleanup flow,
i.e. into io_clean_op(), so making it cleaner.

Also move io_req_needs_clean() to be first in io_dismantle_req() so it
doesn't reload req->flags.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/90653a3a5de4107e3a00536fa4c2ea5f2c38a4ac.1618916549.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 12:55:28 -06:00
Jens Axboe
eb37267229 io-wq: remove unused io_wqe_need_worker() function
A previous commit removed the need for this, but overlooked that we no
longer use it at all. Get rid of it.

Fixes: 685fe7feed ("io-wq: eliminate the need for a manager thread")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 11:24:22 -06:00
Pavel Begunkov
734551df6f io_uring: fix shared sqpoll cancellation hangs
[  736.982891] INFO: task iou-sqp-4294:4295 blocked for more than 122 seconds.
[  736.982897] Call Trace:
[  736.982901]  schedule+0x68/0xe0
[  736.982903]  io_uring_cancel_sqpoll+0xdb/0x110
[  736.982908]  io_sqpoll_cancel_cb+0x24/0x30
[  736.982911]  io_run_task_work_head+0x28/0x50
[  736.982913]  io_sq_thread+0x4e3/0x720

We call io_uring_cancel_sqpoll() one by one for each ctx either in
sq_thread() itself or via task works, and it's intended to cancel all
requests of a specified context. However the function uses per-task
counters to track the number of inflight requests, so it counts more
requests than available via currect io_uring ctx and goes to sleep for
them to appear (e.g. from IRQ), that will never happen.

Cancel a bit more than before, i.e. all ctxs that share sqpoll
and continue to use shared counters. Don't forget that we should not
remove ctx from the list before running that task_work sqpoll-cancel,
otherwise the function wouldn't be able to find the context and will
hang.

Reported-by: Joakim Hassila <joj@mac.com>
Reported-by: Jens Axboe <axboe@kernel.dk>
Fixes: 37d1e2e364 ("io_uring: move SQPOLL thread io-wq forked worker")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1bded7e6c6b32e0bae25fce36be2868e46b116a0.1618752958.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-19 11:34:32 -06:00
Pavel Begunkov
3b763ba1c7 io_uring: remove extra sqpoll submission halting
SQPOLL task won't submit requests for a context that is currently dying,
so no need to remove ctx from sqd_list prior the main loop of
io_ring_exit_work(). Kill it, will be removed by io_sq_thread_finish()
and only brings confusion and lockups.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/f220c2b786ba0f9499bebc9f3cd9714d29efb6a5.1618752958.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-19 11:34:32 -06:00
Pavel Begunkov
75c4021aac io_uring: check register restriction afore quiesce
Move restriction checks of __io_uring_register() before quiesce, saves
from waiting for requests in fail case and simplifies the code a bit.
Also add array_index_nospec() for safety

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/88d7913c9280ee848fdb7b584eea37a465391cee.1618488258.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-17 19:20:08 -06:00
Pavel Begunkov
38134ada0c io_uring: fix overflows checks in provide buffers
Colin reported before possible overflow and sign extension problems in
io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing
useful, see d81269fecb ("io_uring: fix provide_buffers sign extension").

Do that with help of check_<op>_overflow helpers. And fix struct
io_provide_buf::len type, as it doesn't make much sense to keep it
signed.

Reported-by: Colin Ian King <colin.king@canonical.com>
Fixes: efe68c1ca8 ("io_uring: validate the full range of provided buffers for access")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/46538827e70fce5f6cdb50897cff4cacc490f380.1618488258.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-17 19:20:07 -06:00
Pavel Begunkov
c82d5bc703 io_uring: don't fail submit with overflow backlog
Don't fail submission attempts if there are CQEs in the overflow
backlog, but give away the decision making to the userspace. It
might be very inconvenient to the userspace, especially if
submission and completion are done by different threads.

We can remove it because of recent changes, where requests
are now not locked by the backlog, backlog entries are allocated
separately, so they take less space and cgroup accounted.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-17 19:19:41 -06:00
Jens Axboe
a7be7c23cf io_uring: fix merge error for async resubmit
A hand-edit while applying this patch on top of a new base resulted in
a reverted check for re-issue, resulting in spurious -EAGAIN errors.

Fixes: 8c130827f4 ("io_uring: don't alter iopoll reissue fail ret code")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16 09:47:08 -06:00
Jens Axboe
75652a30ff io_uring: tie req->apoll to request lifetime
We manage these separately right now, just tie it to the request lifetime
and make it be part of the usual REQ_F_NEED_CLEANUP logic.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16 09:47:02 -06:00
Jens Axboe
4e3d9ff905 io_uring: put flag checking for needing req cleanup in one spot
We have this in two spots right now, which is a bit fragile. In
preparation for moving REQ_F_POLLED cleanup into the same spot, move
the check into a separate helper so we only have it once.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16 09:45:47 -06:00
Jens Axboe
ea6a693d86 io_uring: disable multishot poll for double poll add cases
The re-add handling isn't correct for the multi wait case, so let's
just disable it for now explicitly until we can get that sorted out. This
just turns it into a one-shot request. Since we pass back whether or not
a poll request terminates in multishot mode on completion, this should
not break properly behaving applications that check for IORING_CQE_F_MORE
on completion.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-15 20:17:11 -06:00
Pavel Begunkov
c5de00366e io_uring: move poll update into remove not add
Having poll update function as a part of IORING_OP_POLL_ADD is not
great, we have to do hack around struct layouts and add some overhead in
the way of more popular POLL_ADD. Even more serious drawback is that
POLL_ADD requires file and always grabs it, and so poll update, which
doesn't need it.

Incorporate poll update into IORING_OP_POLL_REMOVE instead of
IORING_OP_POLL_ADD. It also more consistent with timeout remove/update.

Fixes: b69de288e9 ("io_uring: allow events and user_data update of running poll requests")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-14 10:43:49 -06:00
Pavel Begunkov
9096af3e9c io_uring: add helper for parsing poll events
Isolate poll mask SQE parsing and preparations into a new function,
which will be reused shortly.

Fixes: b69de288e9 ("io_uring: allow events and user_data update of running poll requests")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-14 10:43:47 -06:00
Pavel Begunkov
9ba5fac8cf io_uring: fix POLL_REMOVE removing apoll
Don't allow REQ_OP_POLL_REMOVE to kill apoll requests, users should not
know about it. Also, remove weird -EACCESS in io_poll_update(), it
shouldn't know anything about apoll, and have to work even if happened
to have a poll and an async poll'ed request with same user_data.

Fixes: b69de288e9 ("io_uring: allow events and user_data update of running poll requests")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-14 10:43:42 -06:00
Pavel Begunkov
7f00651aeb io_uring: refactor io_ring_exit_work()
Don't reinit io_ring_exit_work()'s exit work/completions on each
iteration, that's wasteful. Also add list_rotate_left(), so if we failed
to complete the task job, we don't try it again and again but defer it
until others are processed.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-14 10:42:31 -06:00
Pavel Begunkov
f39c8a5b11 io_uring: inline io_iopoll_getevents()
io_iopoll_getevents() is of no use to us anymore, io_iopoll_check()
handles all the cases.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7e50b8917390f38bee4f822c6f4a6a98a27be037.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:55 -06:00
Pavel Begunkov
e9979b36a4 io_uring: skip futile iopoll iterations
The only way to get out of io_iopoll_getevents() and continue iterating
is to have empty iopoll_list, otherwise the main loop would just exit.
So, instead of the unlock on 8th time heuristic, do that based on
iopoll_list.

Also, as no one can add new requests to iopoll_list while
io_iopoll_check() hold uring_lock, it's useless to spin with the list
empty, return in that case.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5b8ebe84f5fff7ffa1f708952dfef7fc78b668e2.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:55 -06:00
Pavel Begunkov
cce4b8b0ce io_uring: don't fail overflow on in_idle
As CQE overflows are now untied from requests and so don't hold any
ref, we don't need to handle exiting/exec'ing cases there anymore.
Moreover, it's much nicer in regards to userspace to save overflowed
CQEs whenever possible, so remove failing on in_idle.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d873b7dab75c7f3039ead9628a745bea01f2cfd2.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:55 -06:00
Pavel Begunkov
e31001a3ab io_uring: clean up io_poll_remove_waitqs()
Move some parts of io_poll_remove_waitqs() that are opcode independent.
Looks better and stresses that both do __io_poll_remove_one().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/bbc717f82117cc335c89cbe67ec8d72608178732.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:55 -06:00
Pavel Begunkov
fd9c7bc542 io_uring: refactor hrtimer_try_to_cancel uses
Don't save return values of hrtimer_try_to_cancel() in a variable, but
use right away. It's in general safer to not have an intermediate
variable, which may be reused and passed out wrongly, but it be
contracted out. Also clean io_timeout_extract().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d2566ef7ce632e6882dc13e022a26249b3fd30b5.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:55 -06:00
Pavel Begunkov
8c855885b8 io_uring: add timeout completion_lock annotation
Add one more sparse locking annotation for readability in
io_kill_timeout().

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/bdbb22026024eac29203c1aa0045c4954a2488d1.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:54 -06:00
Pavel Begunkov
9d8058926b io_uring: split poll and poll update structures
struct io_poll_iocb became pretty nasty combining also update fields.
Split them, so we would have more clarity to it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b2f74d64ffebb57a648f791681af086c7211e3a4.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:54 -06:00
Pavel Begunkov
66d2d00d0a io_uring: fix uninit old data for poll event upd
Both IORING_POLL_UPDATE_EVENTS and IORING_POLL_UPDATE_USER_DATA need
old_user_data to find/cancel a poll request, but it's set only for the
first one.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ab08fd35b7652e977f9a475f01741b04102297f1.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:54 -06:00
Pavel Begunkov
084804002e io_uring: fix leaking reg files on exit
If io_sqe_files_unregister() faults on io_rsrc_ref_quiesce(), it will
fail to do unregister leaving files referenced. And that may well happen
because of a strayed signal or just because it does allocations inside.

In io_ring_ctx_free() do an unsafe version of unregister, as it's
guaranteed to not have requests by that point and so quiesce is useless.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e696e9eade571b51997d0dc1d01f144c6d685c05.1618278933.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-13 09:37:54 -06:00
Pavel Begunkov
f70865db5f io_uring: return back safer resurrect
Revert of revert of "io_uring: wait potential ->release() on resurrect",
which adds a helper for resurrect not racing completion reinit, as was
removed because of a strange bug with no clear root or link to the
patch.

Was improved, instead of rcu_synchronize(), just wait_for_completion()
because we're at 0 refs and it will happen very shortly. Specifically
use non-interruptible version to ignore all pending signals that may
have ended prior interruptible wait.

This reverts commit cb5e1b8130.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7a080c20f686d026efade810b116b72f88abaff9.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:33:10 -06:00
Pavel Begunkov
e4335ed33e io_uring: improve hardlink code generation
req_set_fail_links() condition checking is bulky. Even though it's
always in a slow path, it's inlined and generates lots of extra code,
simplify it be moving HARDLINK checking into helpers killing linked
requests.

          text    data     bss     dec     hex filename
before:  79318   12330       8   91656   16608 ./fs/io_uring.o
after:   79126   12330       8   91464   16548 ./fs/io_uring.o

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/96a9387db658a9d5a44ecbfd57c2a62cb888c9b6.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:33:07 -06:00
Pavel Begunkov
88885f66e8 io_uring: improve sqo stop
Set IO_SQ_THREAD_SHOULD_STOP before taking sqd lock, so the sqpoll task
sees earlier. Not a problem, it will stop eventually. Also check
invariant that it's stopped only once.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/653b24ee93843a50ff65a45847d9138f5adb76d7.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:33:04 -06:00
Pavel Begunkov
aeca241b0b io_uring: split file table from rsrc nodes
We don't need to store file tables in rsrc nodes, for now it's easier to
handle tables not generically, so move file tables into the context. A
nice side effect is having one less pointer dereference for request with
fixed file initialisation.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/de9fc4cd3545f24c26c03be4556f58ba3d18b9c3.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:33:01 -06:00
Pavel Begunkov
87094465d0 io_uring: cleanup buffer register
In preparation for more changes do a little cleanup of
io_sqe_buffers_register(). Move all args/invariant checking into it from
io_buffers_map_alloc(), because it's confusing. And add a bit more
cleaning for the loop.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/93292cb9708c8455e5070cc855861d94e11ca042.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:32:58 -06:00
Pavel Begunkov
7f61a1e9ef io_uring: add buffer unmap helper
Add a helper for unmapping registered buffers, better than double
indexing and will be reused in the future.

Suggested-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/66cbc6ea863be865bac7b7080ed6a3d5c542b71f.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:32:55 -06:00
Pavel Begunkov
3e9424989b io_uring: simplify io_rsrc_data refcounting
We don't take many references of struct io_rsrc_data, only one per each
io_rsrc_node, so using percpu refs is overkill. Use atomic ref instead,
which is much simpler.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1551d90f7c9b183cf2f0d7b5e5b923430acb03fa.1618101759.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 09:32:47 -06:00
Jens Axboe
a1ff1e3f0e io_uring: provide io_resubmit_prep() stub for !CONFIG_BLOCK
Randy reports the following error on CONFIG_BLOCK not being set:

../fs/io_uring.c: In function ‘kiocb_done’:
../fs/io_uring.c:2766:7: error: implicit declaration of function ‘io_resubmit_prep’; did you mean ‘io_put_req’? [-Werror=implicit-function-declaration]
   if (io_resubmit_prep(req)) {

Provide a dummy stub for io_resubmit_prep() like we do for
io_rw_should_reissue(), which also helps remove an ifdef sequence from
io_complete_rw_iopoll() as well.

Fixes: 8c130827f4 ("io_uring: don't alter iopoll reissue fail ret code")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12 06:40:02 -06:00