Currently the kernel will happily route io_uring requests with metadata
to file operations that don't support it.  Add a FMODE_ flag to guard
that.

Fixes: 4de2ce04c862 ("fs: introduce IOCB_HAS_METADATA for metadata")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/20250819082517.2038819-2-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>

kernel test robot reports that a recent change of the sqe->rw_flags
field throws a sparse warning on 32-bit archs:

>> io_uring/rw.c:291:19: sparse: sparse: incorrect type in assignment (different base types) @@     expected restricted __kernel_rwf_t [usertype] flags @@     got unsigned int @@
   io_uring/rw.c:291:19: sparse:     expected restricted __kernel_rwf_t [usertype] flags
   io_uring/rw.c:291:19: sparse:     got unsigned int

Force cast it to rwf_t to silence that new sparse warning.

Fixes: cf73d9970ea4 ("io_uring: don't use int for ABI")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202507032211.PwSNPNSP-lkp@intel.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull io_uring updates from Jens Axboe:

 - Avoid indirect function calls in io-wq for executing and freeing
   work.

   The design of io-wq is such that it can be a generic mechanism, but
   as it's just used by io_uring now, may as well avoid these indirect
   calls

 - Clean up registered buffers for networking

 - Add support for IORING_OP_PIPE. Pretty straight forward, allows
   creating pipes with io_uring, particularly useful for having these be
   instantiated as direct descriptors

 - Clean up the coalescing support fore registered buffers

 - Add support for multiple interface queues for zero-copy rx
   networking. As this feature was merged for 6.15 it supported just a
   single ifq per ring

 - Clean up the eventfd support

 - Add dma-buf support to zero-copy rx

 - Clean up and improving the request draining support

 - Clean up provided buffer support, most notably with an eye toward
   making the legacy support less intrusive

 - Minor fdinfo cleanups, dropping support for dumping what credentials
   are registered

 - Improve support for overflow CQE handling, getting rid of GFP_ATOMIC
   for allocating overflow entries where possible

 - Improve detection of cases where io-wq doesn't need to spawn a new
   worker unnecessarily

 - Various little cleanups

* tag 'for-6.16/io_uring-20250523' of git://git.kernel.dk/linux: (59 commits)
  io_uring/cmd: warn on reg buf imports by ineligible cmds
  io_uring/io-wq: only create a new worker if it can make progress
  io_uring/io-wq: ignore non-busy worker going to sleep
  io_uring/io-wq: move hash helpers to the top
  trace/io_uring: fix io_uring_local_work_run ctx documentation
  io_uring: finish IOU_OK -> IOU_COMPLETE transition
  io_uring: add new helpers for posting overflows
  io_uring: pass in struct io_big_cqe to io_alloc_ocqe()
  io_uring: make io_alloc_ocqe() take a struct io_cqe pointer
  io_uring: split alloc and add of overflow
  io_uring: open code io_req_cqe_overflow()
  io_uring/fdinfo: get rid of dumping credentials
  io_uring/fdinfo: only compile if CONFIG_PROC_FS is set
  io_uring/kbuf: unify legacy buf provision and removal
  io_uring/kbuf: refactor __io_remove_buffers
  io_uring/kbuf: don't compute size twice on prep
  io_uring/kbuf: drop extra vars in io_register_pbuf_ring
  io_uring/kbuf: use mem_is_zero()
  io_uring/kbuf: account ring io_buffer_list memory
  io_uring: drain based on allocates reqs
  ...

IOU_COMPLETE is more descriptive, in that it explicitly says that the
return value means "please post a completion for this request". This
patch completes the transition from IOU_OK to IOU_COMPLETE, replacing
existing IOU_OK users.

This is a purely mechanical change.

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

Allow userspace to pass a per-I/O write stream in the SQE:

      __u8 write_stream;

The __u8 type matches the size the filesystems and block layer support.

Application can query the supported values from the block devices
max_write_streams sysfs attribute. Unsupported values are ignored by
file operations that do not support write streams or rejected with an
error by those that support them.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20250506121732.8211-7-joshi.k@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The current situation with buffer group id juggling is not ideal.
req->buf_index first stores the bgid, then it's overwritten by a buffer
id, and then it can get restored back no recycling / etc. It's not so
easy to control, and it's not handled consistently across request types
with receive requests saving and restoring the bgid it by hand.

It's a prep patch that adds a buffer group id argument to
io_buffer_select(). The caller will be responsible for stashing a copy
somewhere and passing it into the function.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a210d6427cc3f4f42271a6853274cd5a50e56820.1743437358.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull more io_uring updates from Jens Axboe:
 "Final separate updates for io_uring.

  This started out as a series of cleanups improvements and improvements
  for registered buffers, but as the last series of the io_uring changes
  for 6.15, it also collected a few fixes for the other branches on top:

   - Add support for vectored fixed/registered buffers.

     Previously only single segments have been supported for commands,
     now vectored variants are supported as well. This series includes
     networking and file read/write support.

   - Small series unifying return codes across multi and single shot.

   - Small series cleaning up registerd buffer importing.

   - Adding support for vectored registered buffers for uring_cmd.

   - Fix for io-wq handling of command reissue.

   - Various little fixes and tweaks"

* tag 'for-6.15/io_uring-reg-vec-20250327' of git://git.kernel.dk/linux: (25 commits)
  io_uring/net: fix io_req_post_cqe abuse by send bundle
  io_uring/net: use REQ_F_IMPORT_BUFFER for send_zc
  io_uring: move min_events sanitisation
  io_uring: rename "min" arg in io_iopoll_check()
  io_uring: open code __io_post_aux_cqe()
  io_uring: defer iowq cqe overflow via task_work
  io_uring: fix retry handling off iowq
  io_uring/net: only import send_zc buffer once
  io_uring/cmd: introduce io_uring_cmd_import_fixed_vec
  io_uring/cmd: add iovec cache for commands
  io_uring/cmd: don't expose entire cmd async data
  io_uring: rename the data cmd cache
  io_uring: rely on io_prep_reg_vec for iovec placement
  io_uring: introduce io_prep_reg_iovec()
  io_uring: unify STOP_MULTISHOT with IOU_OK
  io_uring: return -EAGAIN to continue multishot
  io_uring: cap cached iovec/bvec size
  io_uring/net: implement vectored reg bufs for zctx
  io_uring/net: convert to struct iou_vec
  io_uring/net: pull vec alloc out of msghdr import
  ...

Pull io_uring updates from Jens Axboe:
 "This is the first of the io_uring pull requests for the 6.15 merge
  window, there will be others once the net tree has gone in. This
  contains:

   - Cleanup and unification of cancelation handling across various
     request types.

   - Improvement for bundles, supporting them both for incrementally
     consumed buffers, and for non-multishot requests.

   - Enable toggling of using iowait while waiting on io_uring events or
     not. Unfortunately this is still tied with CPU frequency boosting
     on short waits, as the scheduler side has not been very receptive
     to splitting the (useless) iowait stat from the cpufreq implied
     boost.

   - Add support for kbuf nodes, enabling zero-copy support for the ublk
     block driver.

   - Various cleanups for resource node handling.

   - Series greatly cleaning up the legacy provided (non-ring based)
     buffers. For years, we've been pushing the ring provided buffers as
     the way to go, and that is what people have been using. Reduce the
     complexity and code associated with legacy provided buffers.

   - Series cleaning up the compat handling.

   - Series improving and cleaning up the recvmsg/sendmsg iovec and msg
     handling.

   - Series of cleanups for io-wq.

   - Start adding a bunch of selftests. The liburing repository
     generally carries feature and regression tests for everything, but
     at least for ublk initially, we'll try and go the route of having
     it in selftests as well. We'll see how this goes, might decide to
     migrate more tests this way in the future.

   - Various little cleanups and fixes"

* tag 'for-6.15/io_uring-20250322' of git://git.kernel.dk/linux: (108 commits)
  selftests: ublk: add stripe target
  selftests: ublk: simplify loop io completion
  selftests: ublk: enable zero copy for null target
  selftests: ublk: prepare for supporting stripe target
  selftests: ublk: move common code into common.c
  selftests: ublk: increase max buffer size to 1MB
  selftests: ublk: add single sqe allocator helper
  selftests: ublk: add generic_01 for verifying sequential IO order
  selftests: ublk: fix starting ublk device
  io_uring: enable toggle of iowait usage when waiting on CQEs
  selftests: ublk: fix write cache implementation
  selftests: ublk: add variable for user to not show test result
  selftests: ublk: don't show `modprobe` failure
  selftests: ublk: add one dependency header
  io_uring/kbuf: enable bundles for incrementally consumed buffers
  Revert "io_uring/rsrc: simplify the bvec iter count calculation"
  selftests: ublk: improve test usability
  selftests: ublk: add stress test for covering IO vs. killing ublk server
  selftests: ublk: add one stress test for covering IO vs. removing device
  selftests: ublk: load/unload ublk_drv when preparing & cleaning up tests
  ...

All vectored reg buffer users should use io_import_reg_vec() for iovec
imports, since iovec placement is the function's responsibility and
callers shouldn't know much about it, drop the offset parameter from
io_prep_reg_vec() and calculate it inside.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/08ed87ca4bbc06724373b6ce06f36b703fe60c4e.1741457480.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

iovecs that are turned into registered buffers are imported in a special
way with an offset, so that later we can do an in place translation. Add
a helper function taking care of it.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7de2ecb9ed5efc3c5cf320232236966da5ad4ccc.1741457480.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>