Two of the three callers want them, so return the more usual format,
and shift into the FFS_ form only for the fixed file table.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230620113235.920399-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Just checking the flag directly makes it a lot more obvious what is
going on here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230620113235.920399-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We use task_work for a variety of reasons, but doing completions or
triggering rety after poll are by far the hottest two. Use the indirect
funtion call wrappers to avoid the indirect function call if
CONFIG_RETPOLINE is set.

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

Pull block updates from Jens Axboe:

 - drbd patches, bringing us closer to unifying the out-of-tree version
   and the in tree one (Andreas, Christoph)

 - support for auto-quiesce for the s390 dasd driver (Stefan)

 - MD pull request via Song:
      - md/bitmap: Optimal last page size (Jon Derrick)
      - Various raid10 fixes (Yu Kuai, Li Nan)
      - md: add error_handlers for raid0 and linear (Mariusz Tkaczyk)

 - NVMe pull request via Christoph:
      - Drop redundant pci_enable_pcie_error_reporting (Bjorn Helgaas)
      - Validate nvmet module parameters (Chaitanya Kulkarni)
      - Fence TCP socket on receive error (Chris Leech)
      - Fix async event trace event (Keith Busch)
      - Minor cleanups (Chaitanya Kulkarni, zhenwei pi)
      - Fix and cleanup nvmet Identify handling (Damien Le Moal,
        Christoph Hellwig)
      - Fix double blk_mq_complete_request race in the timeout handler
        (Lei Yin)
      - Fix irq locking in nvme-fcloop (Ming Lei)
      - Remove queue mapping helper for rdma devices (Sagi Grimberg)

 - use structured request attribute checks for nbd (Jakub)

 - fix blk-crypto race conditions between keyslot management (Eric)

 - add sed-opal support for reading read locking range attributes
   (Ondrej)

 - make fault injection configurable for null_blk (Akinobu)

 - clean up the request insertion API (Christoph)

 - clean up the queue running API (Christoph)

 - blkg config helper cleanups (Tejun)

 - lazy init support for blk-iolatency (Tejun)

 - various fixes and tweaks to ublk (Ming)

 - remove hybrid polling. It hasn't really been useful since we got
   async polled IO support, and these days we don't support sync polled
   IO at all (Keith)

 - misc fixes, cleanups, improvements (Zhong, Ondrej, Colin, Chengming,
   Chaitanya, me)

* tag 'for-6.4/block-2023-04-21' of git://git.kernel.dk/linux: (118 commits)
  nbd: fix incomplete validation of ioctl arg
  ublk: don't return 0 in case of any failure
  sed-opal: geometry feature reporting command
  null_blk: Always check queue mode setting from configfs
  block: ublk: switch to ioctl command encoding
  blk-mq: fix the blk_mq_add_to_requeue_list call in blk_kick_flush
  block, bfq: Fix division by zero error on zero wsum
  fault-inject: fix build error when FAULT_INJECTION_CONFIGFS=y and CONFIGFS_FS=m
  block: store bdev->bd_disk->fops->submit_bio state in bdev
  block: re-arrange the struct block_device fields for better layout
  md/raid5: remove unused working_disks variable
  md/raid10: don't call bio_start_io_acct twice for bio which experienced read error
  md/raid10: fix memleak of md thread
  md/raid10: fix memleak for 'conf->bio_split'
  md/raid10: fix leak of 'r10bio->remaining' for recovery
  md/raid10: don't BUG_ON() in raise_barrier()
  md: fix soft lockup in status_resync
  md: add error_handlers for raid0 and linear
  md: Use optimal I/O size for last bitmap page
  md: Fix types in sb writer
  ...

Pull io_uring updates from Jens Axboe:

 - Cleanup of the io-wq per-node mapping, notably getting rid of it so
   we just have a single io_wq entry per ring (Breno)

 - Followup to the above, move accounting to io_wq as well and
   completely drop struct io_wqe (Gabriel)

 - Enable KASAN for the internal io_uring caches (Breno)

 - Add support for multishot timeouts. Some applications use timeouts to
   wake someone waiting on completion entries, and this makes it a bit
   easier to just have a recurring timer rather than needing to rearm it
   every time (David)

 - Support archs that have shared cache coloring between userspace and
   the kernel, and hence have strict address requirements for mmap'ing
   the ring into userspace. This should only be parisc/hppa. (Helge, me)

 - XFS has supported O_DIRECT writes without needing to lock the inode
   exclusively for a long time, and ext4 now supports it as well. This
   is true for the common cases of not extending the file size. Flag the
   fs as having that feature, and utilize that to avoid serializing
   those writes in io_uring (me)

 - Enable completion batching for uring commands (me)

 - Revert patch adding io_uring restriction to what can be GUP mapped or
   not. This does not belong in io_uring, as io_uring isn't really
   special in this regard. Since this is also getting in the way of
   cleanups and improvements to the GUP code, get rid of if (me)

 - A few series greatly reducing the complexity of registered resources,
   like buffers or files. Not only does this clean up the code a lot,
   the simplified code is also a LOT more efficient (Pavel)

 - Series optimizing how we wait for events and run task_work related to
   it (Pavel)

 - Fixes for file/buffer unregistration with DEFER_TASKRUN (Pavel)

 - Misc cleanups and improvements (Pavel, me)

* tag 'for-6.4/io_uring-2023-04-21' of git://git.kernel.dk/linux: (71 commits)
  Revert "io_uring/rsrc: disallow multi-source reg buffers"
  io_uring: add support for multishot timeouts
  io_uring/rsrc: disassociate nodes and rsrc_data
  io_uring/rsrc: devirtualise rsrc put callbacks
  io_uring/rsrc: pass node to io_rsrc_put_work()
  io_uring/rsrc: inline io_rsrc_put_work()
  io_uring/rsrc: add empty flag in rsrc_node
  io_uring/rsrc: merge nodes and io_rsrc_put
  io_uring/rsrc: infer node from ctx on io_queue_rsrc_removal
  io_uring/rsrc: remove unused io_rsrc_node::llist
  io_uring/rsrc: refactor io_queue_rsrc_removal
  io_uring/rsrc: simplify single file node switching
  io_uring/rsrc: clean up __io_sqe_buffers_update()
  io_uring/rsrc: inline switch_start fast path
  io_uring/rsrc: remove rsrc_data refs
  io_uring/rsrc: fix DEFER_TASKRUN rsrc quiesce
  io_uring/rsrc: use wq for quiescing
  io_uring/rsrc: refactor io_rsrc_ref_quiesce
  io_uring/rsrc: remove io_rsrc_node::done
  io_uring/rsrc: use nospec'ed indexes
  ...

Every task_work will try to wake the task to be executed, which causes
excessive scheduling and additional overhead. For some tw it's
justified, but others won't do much but post a single CQE.

When a task waits for multiple cqes, every such task_work will wake it
up. Instead, the task may give a hint about how many cqes it waits for,
io_req_local_work_add() will compare against it and skip wake ups
if #cqes + #tw is not enough to satisfy the waiting condition. Task_work
that uses the optimisation should be simple enough and never post more
than one CQE. It's also ignored for non DEFER_TASKRUN rings.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d2b77e99d1e86624d8a69f7037d764b739dcd225.1680782017.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

For task works we're passing around a bool pointer for whether the
current ring is locked or not, let's wrap it in a structure, that
will make it more opaque preventing abuse and will also help us
to pass more info in the future if needed.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1ecec9483d58696e248d1bfd52cf62b04442df1d.1679931367.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

These just return the address and length of the current iovec segment
in the iterator. Convert existing iov_iter_iovec() users to use them
instead of getting a copy of the current vec.

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

This returns a pointer to the current iovec entry in the iterator. Only
useful with ITER_IOVEC right now, but it prepares us to treat ITER_UBUF
and ITER_IOVEC identically for the first segment.

Rename struct iov_iter->iov to iov_iter->__iov to find any potentially
troublesome spots, and also to prevent anyone from adding new code that
accesses iter->iov directly.

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

io_uring provides the only way user space can poll completions, and that
always sets BLK_POLL_NOSLEEP. This effectively makes hybrid polling dead
code, so remove it and everything supporting it.

Hybrid polling was effectively killed off with 9650b453a3d4b1, "block:
ignore RWF_HIPRI hint for sync dio", but still potentially reachable
through io_uring until d729cf9acb93119, "io_uring: don't sleep when
polling for I/O", but hybrid polling probably should not have been
reachable through that async interface from the beginning.

Fixes: 9650b453a3d4 ("block: ignore RWF_HIPRI hint for sync dio")
Fixes: d729cf9acb93 ("io_uring: don't sleep when polling for I/O")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20230320194926.3353144-1-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>