linux-toradex.git/include/uapi/linux/io_uring.h, branch v5.15-rc5

io-wq: provide IO_WQ_* constants for IORING_REGISTER_IOWQ_MAX_WORKERS arg items

2021-09-13T16:38:13+00:00

The items passed in the array pointed by the arg parameter
of IORING_REGISTER_IOWQ_MAX_WORKERS io_uring_register operation
carry certain semantics: they refer to different io-wq worker categories;
provide IO_WQ_* constants in the UAPI, so these categories can be referenced
in the user space code.

Suggested-by: Jens Axboe 
Complements: 2e480058ddc21ec5 ("io-wq: provide a way to limit max number of workers")
Signed-off-by: Eugene Syromiatnikov 
Link: https://lore.kernel.org/r/20210913154415.GA12890@asgard.redhat.com
Signed-off-by: Jens Axboe

Merge tag 'for-5.15/io_uring-vfs-2021-08-30' of git://git.kernel.dk/linux-block

2021-08-31T02:39:59+00:00

Pull io_uring mkdirat/symlinkat/linkat support from Jens Axboe:
 "This adds io_uring support for mkdirat, symlinkat, and linkat"

* tag 'for-5.15/io_uring-vfs-2021-08-30' of git://git.kernel.dk/linux-block:
  io_uring: add support for IORING_OP_LINKAT
  io_uring: add support for IORING_OP_SYMLINKAT
  io_uring: add support for IORING_OP_MKDIRAT
  namei: update do_*() helpers to return ints
  namei: make do_linkat() take struct filename
  namei: add getname_uflags()
  namei: make do_symlinkat() take struct filename
  namei: make do_mknodat() take struct filename
  namei: make do_mkdirat() take struct filename
  namei: change filename_parentat() calling conventions
  namei: ignore ERR/NULL names in putname()

io_uring: allow updating linked timeouts

2021-08-29T22:12:21+00:00

We allow updating normal timeouts, add support for adjusting timings of
linked timeouts as well.

Reported-by: Victor Stewart 
Signed-off-by: Pavel Begunkov 
Signed-off-by: Jens Axboe

io_uring: support CLOCK_BOOTTIME/REALTIME for timeouts

2021-08-29T13:57:23+00:00

Certain use cases want to use CLOCK_BOOTTIME or CLOCK_REALTIME rather than
CLOCK_MONOTONIC, instead of the default CLOCK_MONOTONIC.

Add an IORING_TIMEOUT_BOOTTIME and IORING_TIMEOUT_REALTIME flag that
allows timeouts and linked timeouts to use the selected clock source.

Only one clock source may be selected, and we -EINVAL the request if more
than one is given. If neither BOOTIME nor REALTIME are selected, the
previous default of MONOTONIC is used.

Link: https://github.com/axboe/liburing/issues/369
Signed-off-by: Jens Axboe

io-wq: provide a way to limit max number of workers

2021-08-29T13:55:55+00:00

io-wq divides work into two categories:

1) Work that completes in a bounded time, like reading from a regular file
   or a block device. This type of work is limited based on the size of
   the SQ ring.

2) Work that may never complete, we call this unbounded work. The amount
   of workers here is just limited by RLIMIT_NPROC.

For various uses cases, it's handy to have the kernel limit the maximum
amount of pending workers for both categories. Provide a way to do with
with a new IORING_REGISTER_IOWQ_MAX_WORKERS operation.

IORING_REGISTER_IOWQ_MAX_WORKERS takes an array of two integers and sets
the max worker count to what is being passed in for each category. The
old values are returned into that same array. If 0 is being passed in for
either category, it simply returns the current value.

The value is capped at RLIMIT_NPROC. This actually isn't that important
as it's more of a hint, if we're exceeding the value then our attempt
to fork a new worker will fail. This happens naturally already if more
than one node is in the system, as these values are per-node internally
for io-wq.

Reported-by: Johannes Lundberg 
Link: https://github.com/axboe/liburing/issues/420
Signed-off-by: Jens Axboe

io_uring: openat directly into fixed fd table

2021-08-25T12:36:56+00:00

Instead of opening a file into a process's file table as usual and then
registering the fd within io_uring, some users may want to skip the
first step and place it directly into io_uring's fixed file table.
This patch adds such a capability for IORING_OP_OPENAT and
IORING_OP_OPENAT2.

The behaviour is controlled by setting sqe->file_index, where 0 implies
the old behaviour using normal file tables. If non-zero value is
specified, then it will behave as described and place the file into a
fixed file slot sqe->file_index - 1. A file table should be already
created, the slot should be valid and empty, otherwise the operation
will fail.

Keep the error codes consistent with IORING_OP_FILES_UPDATE, ENXIO and
EINVAL on inappropriate fixed tables, and return EBADF on collision with
already registered file.

Note: IOSQE_FIXED_FILE can't be used to switch between modes, because
accept takes a file, and it already uses the flag with a different
meaning.

Suggested-by: Josh Triplett 
Signed-off-by: Pavel Begunkov 
Signed-off-by: Jens Axboe 
Link: https://lore.kernel.org/r/e9b33d1163286f51ea707f87d95bd596dada1e65.1629888991.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe

io_uring: add support for IORING_OP_LINKAT

2021-08-23T19:48:52+00:00

IORING_OP_LINKAT behaves like linkat(2) and takes the same flags and
arguments.

In some internal places 'hardlink' is used instead of 'link' to avoid
confusion with the SQE links. Name 'link' conflicts with the existing
'link' member of io_kiocb.

Acked-by: Linus Torvalds 
Suggested-by: Christian Brauner 
Link: https://lore.kernel.org/io-uring/20210514145259.wtl4xcsp52woi6ab@wittgenstein/
Signed-off-by: Dmitry Kadashev 
Acked-by: Christian Brauner 
Link: https://lore.kernel.org/r/20210708063447.3556403-12-dkadashev@gmail.com
[axboe: add splice_fd_in check]
Signed-off-by: Jens Axboe

io_uring: add support for IORING_OP_SYMLINKAT

2021-08-23T19:48:33+00:00

IORING_OP_SYMLINKAT behaves like symlinkat(2) and takes the same flags
and arguments.

Acked-by: Linus Torvalds 
Suggested-by: Christian Brauner 
Link: https://lore.kernel.org/io-uring/20210514145259.wtl4xcsp52woi6ab@wittgenstein/
Signed-off-by: Dmitry Kadashev 
Acked-by: Christian Brauner 
Link: https://lore.kernel.org/r/20210708063447.3556403-11-dkadashev@gmail.com
[axboe: add splice_fd_in check]
Signed-off-by: Jens Axboe

io_uring: add support for IORING_OP_MKDIRAT

2021-08-23T19:41:26+00:00

IORING_OP_MKDIRAT behaves like mkdirat(2) and takes the same flags
and arguments.

Acked-by: Linus Torvalds 
Signed-off-by: Dmitry Kadashev 
Acked-by: Christian Brauner 
Link: https://lore.kernel.org/r/20210708063447.3556403-10-dkadashev@gmail.com
[axboe: add splice_fd_in check]
Signed-off-by: Jens Axboe

io_uring: simplify struct io_uring_sqe layout

2021-06-30T20:15:39+00:00

Flatten struct io_uring_sqe, the last union is exactly 64B, so move them
out of union { struct { ... }}, and decrease __pad2 size.

Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/2e21ef7aed136293d654450bc3088973a8adc730.1624543113.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe