linux-toradex.git/include/uapi/linux/io_uring.h, branch v6.4-rc1

io_uring: add support for multishot timeouts

2023-04-19T01:38:36+00:00

A multishot timeout submission will repeatedly generate completions with
the IORING_CQE_F_MORE cflag set. Depending on the value of the `off'
field in the submission, these timeouts can either repeat indefinitely
until cancelled (`off' = 0) or for a fixed number of times (`off' > 0).

Only noseq timeouts (i.e. not dependent on the number of I/O
completions) are supported.

An indefinite timer will be cancelled if the CQ ever overflows.

Signed-off-by: David Wei 
Link: https://lore.kernel.org/r/20230418225817.1905027-1-davidhwei@meta.com
Signed-off-by: Jens Axboe

io_uring: kill unused notif declarations

2023-04-03T13:16:15+00:00

There are two leftover structures from the notification registration
mechanism that has never been released, kill them.

Signed-off-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/f05f65aebaf8b1b5bf28519a8fdb350e3e7c9ad0.1679924536.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe

io_uring: add support for user mapped provided buffer ring

2023-04-03T13:14:21+00:00

The ring mapped provided buffer rings rely on the application allocating
the memory for the ring, and then the kernel will map it. This generally
works fine, but runs into issues on some architectures where we need
to be able to ensure that the kernel and application virtual address for
the ring play nicely together. This at least impacts architectures that
set SHM_COLOUR, but potentially also anyone setting SHMLBA.

To use this variant of ring provided buffers, the application need not
allocate any memory for the ring. Instead the kernel will do so, and
the allocation must subsequently call mmap(2) on the ring with the
offset set to:

	IORING_OFF_PBUF_RING | (bgid << IORING_OFF_PBUF_SHIFT)

to get a virtual address for the buffer ring. Normally the application
would allocate a suitable piece of memory (and correctly aligned) and
simply pass that in via io_uring_buf_reg.ring_addr and the kernel would
map it.

Outside of the setup differences, the kernel allocate + user mapped
provided buffer ring works exactly the same.

Acked-by: Helge Deller 
Signed-off-by: Jens Axboe

io_uring/kbuf: rename struct io_uring_buf_reg 'pad' to'flags'

2023-04-03T13:14:21+00:00

In preparation for allowing flags to be set for registration, rename
the padding and use it for that.

Acked-by: Helge Deller 
Signed-off-by: Jens Axboe

Merge tag 'hardening-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2023-02-21T19:07:23+00:00

Pull hardening updates from Kees Cook:
 "Beyond some specific LoadPin, UBSAN, and fortify features, there are
  other fixes scattered around in various subsystems where maintainers
  were okay with me carrying them in my tree or were non-responsive but
  the patches were reviewed by others:

   - Replace 0-length and 1-element arrays with flexible arrays in
     various subsystems (Paulo Miguel Almeida, Stephen Rothwell, Kees
     Cook)

   - randstruct: Disable Clang 15 support (Eric Biggers)

   - GCC plugins: Drop -std=gnu++11 flag (Sam James)

   - strpbrk(): Refactor to use strchr() (Andy Shevchenko)

   - LoadPin LSM: Allow root filesystem switching when non-enforcing

   - fortify: Use dynamic object size hints when available

   - ext4: Fix CFI function prototype mismatch

   - Nouveau: Fix DP buffer size arguments

   - hisilicon: Wipe entire crypto DMA pool on error

   - coda: Fully allocate sig_inputArgs

   - UBSAN: Improve arm64 trap code reporting

   - copy_struct_from_user(): Add minimum bounds check on kernel buffer
     size"

* tag 'hardening-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  randstruct: disable Clang 15 support
  uaccess: Add minimum bounds check on kernel buffer size
  arm64: Support Clang UBSAN trap codes for better reporting
  coda: Avoid partial allocation of sig_inputArgs
  gcc-plugins: drop -std=gnu++11 to fix GCC 13 build
  lib/string: Use strchr() in strpbrk()
  crypto: hisilicon: Wipe entire pool on error
  net/i40e: Replace 0-length array with flexible array
  io_uring: Replace 0-length array with flexible array
  ext4: Fix function prototype mismatch for ext4_feat_ktype
  i915/gvt: Replace one-element array with flexible-array member
  drm/nouveau/disp: Fix nvif_outp_acquire_dp() argument size
  LoadPin: Allow filesystem switch when not enforcing
  LoadPin: Move pin reporting cleanly out of locking
  LoadPin: Refactor sysctl initialization
  LoadPin: Refactor read-only check into a helper
  ARM: ixp4xx: Replace 0-length arrays with flexible arrays
  fortify: Use __builtin_dynamic_object_size() when available
  rxrpc: replace zero-lenth array with DECLARE_FLEX_ARRAY() helper

io_uring: Support calling io_uring_register with a registered ring fd

2023-02-16T13:09:30+00:00

Add a new flag IORING_REGISTER_USE_REGISTERED_RING (set via the high bit
of the opcode) to treat the fd as a registered index rather than a file
descriptor.

This makes it possible for a library to open an io_uring, register the
ring fd, close the ring fd, and subsequently use the ring entirely via
registered index.

Signed-off-by: Josh Triplett 
Link: https://lore.kernel.org/r/f2396369e638284586b069dbddffb8c992afba95.1676419314.git.josh@joshtriplett.org
[axboe: remove extra high bit clear]
Signed-off-by: Jens Axboe

io_uring/msg_ring: Pass custom flags to the cqe

2023-01-29T22:17:40+00:00

This patch adds a new flag (IORING_MSG_RING_FLAGS_PASS) in the message
ring operations (IORING_OP_MSG_RING). This new flag enables the sender
to specify custom flags, which will be copied over to cqe->flags in the
receiving ring.  These custom flags should be specified using the
sqe->file_index field.

This mechanism provides additional flexibility when sending messages
between rings.

Signed-off-by: Breno Leitao 
Link: https://lore.kernel.org/r/20230103160507.617416-1-leitao@debian.org
Signed-off-by: Jens Axboe

io_uring: Replace 0-length array with flexible array

2023-01-27T19:42:57+00:00

Zero-length arrays are deprecated[1]. Replace struct io_uring_buf_ring's
"bufs" with a flexible array member. (How is the size of this array
verified?) Detected with GCC 13, using -fstrict-flex-arrays=3:

In function 'io_ring_buffer_select',
    inlined from 'io_buffer_select' at io_uring/kbuf.c:183:10:
io_uring/kbuf.c:141:23: warning: array subscript 255 is outside the bounds of an interior zero-length array 'struct io_uring_buf[0]' [-Wzero-length-bounds]
  141 |                 buf = &br->bufs[head];
      |                       ^~~~~~~~~~~~~~~
In file included from include/linux/io_uring.h:7,
                 from io_uring/kbuf.c:10:
include/uapi/linux/io_uring.h: In function 'io_buffer_select':
include/uapi/linux/io_uring.h:628:41: note: while referencing 'bufs'
  628 |                 struct io_uring_buf     bufs[0];
      |                                         ^~~~

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Fixes: c7fb19428d67 ("io_uring: add support for ring mapped supplied buffers")
Cc: Jens Axboe 
Cc: Pavel Begunkov 
Cc: "Gustavo A. R. Silva" 
Cc: stable@vger.kernel.org
Cc: io-uring@vger.kernel.org
Signed-off-by: Kees Cook 
Reviewed-by: Gustavo A. R. Silva 
Link: https://lore.kernel.org/r/20230105190507.gonna.131-kees@kernel.org

uapi:io_uring.h: allow linux/time_types.h to be skipped

2022-12-27T14:32:51+00:00

include/uapi/linux/io_uring.h is synced 1:1 into
liburing:src/include/liburing/io_uring.h.

liburing has a configure check to detect the need for
linux/time_types.h. It can opt-out by defining
UAPI_LINUX_IO_URING_H_SKIP_LINUX_TIME_TYPES_H

Fixes: 78a861b94959 ("io_uring: add sync cancelation API through io_uring_register()")
Link: https://github.com/axboe/liburing/issues/708
Link: https://github.com/axboe/liburing/pull/709
Link: https://lore.kernel.org/io-uring/20221115212614.1308132-1-ammar.faizi@intel.com/T/#m9f5dd571cd4f6a5dee84452dbbca3b92ba7a4091
CC: Jens Axboe 
Cc: Ammar Faizi 
Signed-off-by: Stefan Metzmacher 
Reviewed-by: Ammar Faizi 
Link: https://lore.kernel.org/r/7071a0a1d751221538b20b63f9160094fc7e06f4.1668630247.git.metze@samba.org
Signed-off-by: Jens Axboe

io_uring/net: introduce IORING_SEND_ZC_REPORT_USAGE flag

2022-11-21T14:38:31+00:00

It might be useful for applications to detect if a zero copy transfer with
SEND[MSG]_ZC was actually possible or not. The application can fallback to
plain SEND[MSG] in order to avoid the overhead of two cqes per request. Or
it can generate a log message that could indicate to an administrator that
no zero copy was possible and could explain degraded performance.

Cc: stable@vger.kernel.org # 6.1
Link: https://lore.kernel.org/io-uring/fb6a7599-8a9b-15e5-9b64-6cd9d01c6ff4@gmail.com/T/#m2b0d9df94ce43b0e69e6c089bdff0ce6babbdfaa
Signed-off-by: Stefan Metzmacher 
Reviewed-by: Pavel Begunkov 
Link: https://lore.kernel.org/r/8945b01756d902f5d5b0667f20b957ad3f742e5e.1666895626.git.metze@samba.org
Signed-off-by: Jens Axboe