Commit Graph

1300 Commits

Author SHA1 Message Date
Linus Torvalds
77a0cfafa9 for-6.13/block-20241118
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmc7S40QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpjHVD/43rDZ8ehs+IAAr6S0RemNX1SRG0mK2UOEb
 kMoNogS7StO/c4JYW3JuzCyLRn5ZsgeWV/muqxwDEWQrmTGrvi+V45KikrZPwm3k
 p0ump33qV9EU2jiR1MKZjtwK2P0CI7/DD3W8ww6IOvKbTT7RcqQcdHznvXArFBtc
 xCuQPpayFG7ZasC+N9VaBwtiUEVgU3Ek9AFT7UVZRWajjHPNalQwaooJWayO0rEG
 KdoW5yG0ryLrgCY2ACSvRLS+2s14EJtb8hgT08WKHTNgd5LxhSKxfsTapamua+7U
 FdVS6Ij0tEkgu2jpvgj7QKO0Uw10Cnep2gj7RHts/LVewvkliS6XcheOzqRS1jWU
 I2EI+UaGOZ11OUiw52VIveEVS5zV/NWhgy5BSP9LYEvXw0BUAHRDYGMem8o5G1V1
 SWqjIM1UWvcQDlAnMF9FDVzojvjVUmYWvcAlFFztO8J0B7SavHR3NcfHwEf57reH
 rNoUbi/9c4/wjJJF33gejiR5pU+ewy/Mk75GrtX3xpEqlztfRbf9/FbPCMEAO1KR
 DF/b3lkUV9i2/BRW6a0SpZ5RDSmSYMnateel6TrPyVSRnpiSSFO8FrbynwUOa17b
 6i49YDFWzzXOrR1YWDg6IEtTrcmBEmvi7F6aoDs020qUnL0hwLn1ZuoIxuiFEpor
 Z0iFF1B/nw==
 =PWTH
 -----END PGP SIGNATURE-----

Merge tag 'for-6.13/block-20241118' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe updates via Keith:
      - Use uring_cmd helper (Pavel)
      - Host Memory Buffer allocation enhancements (Christoph)
      - Target persistent reservation support (Guixin)
      - Persistent reservation tracing (Guixen)
      - NVMe 2.1 specification support (Keith)
      - Rotational Meta Support (Matias, Wang, Keith)
      - Volatile cache detection enhancment (Guixen)

 - MD updates via Song:
      - Maintainers update
      - raid5 sync IO fix
      - Enhance handling of faulty and blocked devices
      - raid5-ppl atomic improvement
      - md-bitmap fix

 - Support for manually defining embedded partition tables

 - Zone append fixes and cleanups

 - Stop sending the queued requests in the plug list to the driver
   ->queue_rqs() handle in reverse order.

 - Zoned write plug cleanups

 - Cleanups disk stats tracking and add support for disk stats for
   passthrough IO

 - Add preparatory support for file system atomic writes

 - Add lockdep support for queue freezing. Already found a bunch of
   issues, and some fixes for that are in here. More will be coming.

 - Fix race between queue stopping/quiescing and IO queueing

 - ublk recovery improvements

 - Fix ublk mmap for 64k pages

 - Various fixes and cleanups

* tag 'for-6.13/block-20241118' of git://git.kernel.dk/linux: (118 commits)
  MAINTAINERS: Update git tree for mdraid subsystem
  block: make struct rq_list available for !CONFIG_BLOCK
  block/genhd: use seq_put_decimal_ull for diskstats decimal values
  block: don't reorder requests in blk_mq_add_to_batch
  block: don't reorder requests in blk_add_rq_to_plug
  block: add a rq_list type
  block: remove rq_list_move
  virtio_blk: reverse request order in virtio_queue_rqs
  nvme-pci: reverse request order in nvme_queue_rqs
  btrfs: validate queue limits
  block: export blk_validate_limits
  nvmet: add tracing of reservation commands
  nvme: parse reservation commands's action and rtype to string
  nvmet: report ns's vwc not present
  md/raid5: Increase r5conf.cache_name size
  block: remove the ioprio field from struct request
  block: remove the write_hint field from struct request
  nvme: check ns's volatile write cache not present
  nvme: add rotational support
  nvme: use command set independent id ns if available
  ...
2024-11-18 16:50:08 -08:00
Linus Torvalds
c14a8a4c04 for-6.13-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmc0zT4ACgkQxWXV+ddt
 WDtThRAAhzSSiHcJqTfCL5nHh7w85MNEVw28o1ETgXSYJmx0JOWLE7Znlp2FV7jj
 IbYkFfF2gXJzYvRZkcXB/TAHV9KJG5yZIBZfccbM+9db9f8xkImVKMuqQRXPU41R
 ppSCmqZTeujtt8ucsaJkMpm6pzECKJCJaGOsMJ8fiqKpo89dKO3eGAVboSbpPF4C
 r0YmppiBwSP/cCXQCqWxZRbqPGN+lUgZpIGNRi157kehfmRHlVVJTO1pgqK8PCXb
 uIT09Kulppfez8+1A10CPcniDTyinLik/qLTNlzdWoDBL4iNJMg0A0wsA04AJVf0
 PdOS0REusiv3QcEIO6PefuRFRRfXcSLPpPDUceltJT5O0uM2gUqf2C7dEHXUGU3o
 TdgYlbQpsJWpZ7VGWQDZeGGV04lOPQvu0LGLPgEerUQd5H9ABa0dX8Fn0sPhKsa8
 whpAcdfE4rdNxB2OJFnqQeFq0z3cSjP/rvKlluCmAj97QYI+kiu3QyhemcT1YSC9
 U7n5Ya9IzIYCN3ml54q3hEgyD0IVGGG20GuUmqC9XSP9mrQRC8I1g7v26AiOTrrk
 VhgSdtMmphDxXudifsnYMaQ0Z1QqiUrW1SM/prAEOnBYCo75+HDsTgrq9ithgHoI
 4xz4YXJyMRs18qfTJctXC1wmGuz5plTdQrwarHdNsELN5HEyqX4=
 =aAcf
 -----END PGP SIGNATURE-----

Merge tag 'for-6.13-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "Changes outside of btrfs: add io_uring command flag to track a dying
  task (the rest will go via the block git tree).

  User visible changes:

   - wire encoded read (ioctl) to io_uring commands, this can be used on
     itself, in the future this will allow 'send' to be asynchronous. As
     a consequence, the encoded read ioctl can also work in non-blocking
     mode

   - new ioctl to wait for cleaned subvolumes, no need to use the
     generic and root-only SEARCH_TREE ioctl, will be used by "btrfs
     subvol sync"

   - recognize different paths/symlinks for the same devices and don't
     report them during rescanning, this can be observed with LVM or DM

   - seeding device use case change, the sprout device (the one
     capturing new writes) will not clear the read-only status of the
     super block; this prevents accumulating space from deleted
     snapshots

  Performance improvements:

   - reduce lock contention when traversing extent buffers

   - reduce extent tree lock contention when searching for inline
     backref

   - switch from rb-trees to xarray for delayed ref tracking,
     improvements due to better cache locality, branching factors and
     more compact data structures

   - enable extent map shrinker again (prevent memory exhaustion under
     some types of IO load), reworked to run in a single worker thread
     (there used to be problems causing long stalls under memory
     pressure)

  Core changes:

   - raid-stripe-tree feature updates:
       - make device replace and scrub work
       - implement partial deletion of stripe extents
       - new selftests

   - split the config option BTRFS_DEBUG and add EXPERIMENTAL for
     features that are experimental or with known problems so we don't
     misuse debugging config for that

   - subpage mode updates (sector < page):
       - update compression implementations
       - update writepage, writeback

   - continued folio API conversions:
       - buffered writes

   - make buffered write copy one page at a time, preparatory work for
     future integration with large folios, may cause performance drop

   - proper locking of root item regarding starting send

   - error handling improvements

   - code cleanups and refactoring:
       - dead code removal
       - unused parameter reduction
       - lockdep assertions"

* tag 'for-6.13-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (119 commits)
  btrfs: send: check for read-only send root under critical section
  btrfs: send: check for dead send root under critical section
  btrfs: remove check for NULL fs_info at btrfs_folio_end_lock_bitmap()
  btrfs: fix warning on PTR_ERR() against NULL device at btrfs_control_ioctl()
  btrfs: fix a typo in btrfs_use_zone_append
  btrfs: avoid superfluous calls to free_extent_map() in btrfs_encoded_read()
  btrfs: simplify logic to decrement snapshot counter at btrfs_mksnapshot()
  btrfs: remove hole from struct btrfs_delayed_node
  btrfs: update stale comment for struct btrfs_delayed_ref_node::add_list
  btrfs: add new ioctl to wait for cleaned subvolumes
  btrfs: simplify range tracking in cow_file_range()
  btrfs: remove conditional path allocation in btrfs_read_locked_inode()
  btrfs: push cleanup into btrfs_read_locked_inode()
  io_uring/cmd: let cmds to know about dying task
  btrfs: add struct io_btrfs_cmd as type for io_uring_cmd_to_pdu()
  btrfs: add io_uring command for encoded reads (ENCODED_READ ioctl)
  btrfs: move priv off stack in btrfs_encoded_read_regular_fill_pages()
  btrfs: don't sleep in btrfs_encoded_read() if IOCB_NOWAIT is set
  btrfs: change btrfs_encoded_read() so that reading of extent is done by caller
  btrfs: remove pointless iocb::ki_pos addition in btrfs_encoded_read()
  ...
2024-11-18 16:37:41 -08:00
Linus Torvalds
c6d64479d6 sanitize struct filename and lookup flags handling in statx
and friends
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZzdpZQAKCRBZ7Krx/gZQ
 6whMAQDhlGFV+nGRetwe4t60mVRpxIoc71GLC7b6V8FmyfTI5AEAkAigkJ8KCZDP
 mfGsN/3PtzoxnIkIqdk7Y7q4/fowyAw=
 =4DWZ
 -----END PGP SIGNATURE-----

Merge tag 'pull-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull statx updates from Al Viro:
 "Sanitize struct filename and lookup flags handling in statx and
  friends"

* tag 'pull-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  libfs: kill empty_dir_getattr()
  fs: Simplify getattr interface function checking AT_GETATTR_NOSEC flag
  fs/stat.c: switch to CLASS(fd_raw)
  kill getname_statx_lookup_flags()
  io_statx_prep(): use getname_uflags()
2024-11-18 14:54:10 -08:00
Linus Torvalds
82339c4911 sanitize xattr and io_uring interactions with it,
add *xattrat() syscalls, sanitize struct filename handling in there.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZzdj4gAKCRBZ7Krx/gZQ
 6/02AQC8ndn9i1wLGRb5DdZYGNWUDhXCdPrZCF2nyvU2swCIPwEAm1H5F/bxBXeT
 6qCLHThVw4KTJOT2aDY03ELrxbi8Vg4=
 =35Oj
 -----END PGP SIGNATURE-----

Merge tag 'pull-xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull xattr updates from Al Viro:
 "Sanitize xattr and io_uring interactions with it, add *xattrat()
  syscalls, sanitize struct filename handling in there"

* tag 'pull-xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  xattr: remove redundant check on variable err
  fs/xattr: add *at family syscalls
  new helpers: file_removexattr(), filename_removexattr()
  new helpers: file_listxattr(), filename_listxattr()
  replace do_getxattr() with saner helpers.
  replace do_setxattr() with saner helpers.
  new helper: import_xattr_name()
  fs: rename struct xattr_ctx to kernel_xattr_ctx
  xattr: switch to CLASS(fd)
  io_[gs]etxattr_prep(): just use getname()
  io_uring: IORING_OP_F[GS]ETXATTR is fine with REQ_F_FIXED_FILE
  getname_maybe_null() - the third variant of pathname copy-in
  teach filename_lookup() to treat NULL filename as ""
2024-11-18 12:44:25 -08:00
Linus Torvalds
0f25f0e4ef the bulk of struct fd memory safety stuff
Making sure that struct fd instances are destroyed in the same
 scope where they'd been created, getting rid of reassignments
 and passing them by reference, converting to CLASS(fd{,_pos,_raw}).
 
 We are getting very close to having the memory safety of that stuff
 trivial to verify.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZzdikAAKCRBZ7Krx/gZQ
 69nJAQCmbQHK3TGUbQhOw6MJXOK9ezpyEDN3FZb4jsu38vTIdgEA6OxAYDO2m2g9
 CN18glYmD3wRyU6Bwl4vGODouSJvDgA=
 =gVH3
 -----END PGP SIGNATURE-----

Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull 'struct fd' class updates from Al Viro:
 "The bulk of struct fd memory safety stuff

  Making sure that struct fd instances are destroyed in the same scope
  where they'd been created, getting rid of reassignments and passing
  them by reference, converting to CLASS(fd{,_pos,_raw}).

  We are getting very close to having the memory safety of that stuff
  trivial to verify"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  deal with the last remaing boolean uses of fd_file()
  css_set_fork(): switch to CLASS(fd_raw, ...)
  memcg_write_event_control(): switch to CLASS(fd)
  assorted variants of irqfd setup: convert to CLASS(fd)
  do_pollfd(): convert to CLASS(fd)
  convert do_select()
  convert vfs_dedupe_file_range().
  convert cifs_ioctl_copychunk()
  convert media_request_get_by_fd()
  convert spu_run(2)
  switch spufs_calls_{get,put}() to CLASS() use
  convert cachestat(2)
  convert do_preadv()/do_pwritev()
  fdget(), more trivial conversions
  fdget(), trivial conversions
  privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget()
  o2hb_region_dev_store(): avoid goto around fdget()/fdput()
  introduce "fd_pos" class, convert fdget_pos() users to it.
  fdget_raw() users: switch to CLASS(fd_raw)
  convert vmsplice() to CLASS(fd)
  ...
2024-11-18 12:24:06 -08:00
Linus Torvalds
4c797b11a8 vfs-6.13.file
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZzcW4gAKCRCRxhvAZXjc
 okF+AP9xTMb2SlnRPBOBd9yFcmVXmQi86TSCUPAEVb+wIldGYwD/RIOdvXYJlp9v
 RgJkU1DC3ddkXtONNDY6gFaP+siIWA0=
 =gMc7
 -----END PGP SIGNATURE-----

Merge tag 'vfs-6.13.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs file updates from Christian Brauner:
 "This contains changes the changes for files for this cycle:

   - Introduce a new reference counting mechanism for files.

     As atomic_inc_not_zero() is implemented with a try_cmpxchg() loop
     it has O(N^2) behaviour under contention with N concurrent
     operations and it is in a hot path in __fget_files_rcu().

     The rcuref infrastructures remedies this problem by using an
     unconditional increment relying on safe- and dead zones to make
     this work and requiring rcu protection for the data structure in
     question. This not just scales better it also introduces overflow
     protection.

     However, in contrast to generic rcuref, files require a memory
     barrier and thus cannot rely on *_relaxed() atomic operations and
     also require to be built on atomic_long_t as having massive amounts
     of reference isn't unheard of even if it is just an attack.

     This adds a file specific variant instead of making this a generic
     library.

     This has been tested by various people and it gives consistent
     improvement up to 3-5% on workloads with loads of threads.

   - Add a fastpath for find_next_zero_bit(). Skip 2-levels searching
     via find_next_zero_bit() when there is a free slot in the word that
     contains the next fd. This improves pts/blogbench-1.1.0 read by 8%
     and write by 4% on Intel ICX 160.

   - Conditionally clear full_fds_bits since it's very likely that a bit
     in full_fds_bits has been cleared during __clear_open_fds(). This
     improves pts/blogbench-1.1.0 read up to 13%, and write up to 5% on
     Intel ICX 160.

   - Get rid of all lookup_*_fdget_rcu() variants. They were used to
     lookup files without taking a reference count. That became invalid
     once files were switched to SLAB_TYPESAFE_BY_RCU and now we're
     always taking a reference count. Switch to an already existing
     helper and remove the legacy variants.

   - Remove pointless includes of <linux/fdtable.h>.

   - Avoid cmpxchg() in close_files() as nobody else has a reference to
     the files_struct at that point.

   - Move close_range() into fs/file.c and fold __close_range() into it.

   - Cleanup calling conventions of alloc_fdtable() and expand_files().

   - Merge __{set,clear}_close_on_exec() into one.

   - Make __set_open_fd() set cloexec as well instead of doing it in two
     separate steps"

* tag 'vfs-6.13.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  selftests: add file SLAB_TYPESAFE_BY_RCU recycling stressor
  fs: port files to file_ref
  fs: add file_ref
  expand_files(): simplify calling conventions
  make __set_open_fd() set cloexec state as well
  fs: protect backing files with rcu
  file.c: merge __{set,clear}_close_on_exec()
  alloc_fdtable(): change calling conventions.
  fs/file.c: add fast path in find_next_fd()
  fs/file.c: conditionally clear full_fds
  fs/file.c: remove sanity_check and add likely/unlikely in alloc_fd()
  move close_range(2) into fs/file.c, fold __close_range() into it
  close_files(): don't bother with xchg()
  remove pointless includes of <linux/fdtable.h>
  get rid of ...lookup...fdget_rcu() family
2024-11-18 10:30:29 -08:00
Pavel Begunkov
e358e09a89 io_uring: protect register tracing
Syz reports:

BUG: KCSAN: data-race in __se_sys_io_uring_register / io_sqe_files_register

read-write to 0xffff8881021940b8 of 4 bytes by task 5923 on cpu 1:
 io_sqe_files_register+0x2c4/0x3b0 io_uring/rsrc.c:713
 __io_uring_register io_uring/register.c:403 [inline]
 __do_sys_io_uring_register io_uring/register.c:611 [inline]
 __se_sys_io_uring_register+0x8d0/0x1280 io_uring/register.c:591
 __x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:591
 x64_sys_call+0x202/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881021940b8 of 4 bytes by task 5924 on cpu 0:
 __do_sys_io_uring_register io_uring/register.c:613 [inline]
 __se_sys_io_uring_register+0xe4a/0x1280 io_uring/register.c:591
 __x64_sys_io_uring_register+0x55/0x70 io_uring/register.c:591
 x64_sys_call+0x202/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Which should be due to reading the table size after unlock. We don't
care much as it's just to print it in trace, but we might as well do it
under the lock.

Reported-by: syzbot+5a486fef3de40e0d8c76@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8233af2886a37b57f79e444e3db88fcfda1817ac.1731942203.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-18 09:10:56 -07:00
Pavel Begunkov
a652958888 io_uring/region: fix error codes after failed vmap
io_create_region() jumps after a vmap failure without setting the return
code, it could be 0 or just uninitialised.

Fixes: dfbbfbf191 ("io_uring: introduce concept of memory regions")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0abac19dbf81c061cffaa9534a2471ed5460ad3e.1731803848.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-17 09:01:35 -07:00
Pavel Begunkov
d617b3147d io_uring: restore back registered wait arguments
Now we've got a more generic region registration API, place
IORING_ENTER_EXT_ARG_REG and re-enable it.

First, the user has to register a region with the
IORING_MEM_REGION_REG_WAIT_ARG flag set. It can only be done for a
ring in a disabled state, aka IORING_SETUP_R_DISABLED, to avoid races
with already running waiters. With that we should have stable constant
values for ctx->cq_wait_{size,arg} in io_get_ext_arg_reg() and hence no
READ_ONCE required.

The other API difference is that we're now passing byte offsets instead
of indexes. The user _must_ align all offsets / pointers to the native
word size, failing to do so might but not necessarily has to lead to a
failure usually returned as -EFAULT. liburing will be hiding this
details from users.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/81822c1b4ffbe8ad391b4f9ad1564def0d26d990.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 12:28:38 -07:00
Pavel Begunkov
93238e6618 io_uring: add memory region registration
Regions will serve multiple purposes. First, with it we can decouple
ring/etc. object creation from registration / mapping of the memory they
will be placed in. We already have hacks that allow to put both SQ and
CQ into the same huge page, in the future we should be able to:

region = create_region(io_ring);
create_pbuf_ring(io_uring, region, offset=0);
create_pbuf_ring(io_uring, region, offset=N);

The second use case is efficiently passing parameters. The following
patch enables back on top of regions IORING_ENTER_EXT_ARG_REG, which
optimises wait arguments. It'll also be useful for request arguments
replacing iovecs, msghdr, etc. pointers. Eventually it would also be
handy for BPF as well if it comes to fruition.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0798cf3a14fad19cfc96fc9feca5f3e11481691d.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:58:34 -07:00
Pavel Begunkov
dfbbfbf191 io_uring: introduce concept of memory regions
We've got a good number of mappings we share with the userspace, that
includes the main rings, provided buffer rings, upcoming rings for
zerocopy rx and more. All of them duplicate user argument parsing and
some internal details as well (page pinnning, huge page optimisations,
mmap'ing, etc.)

Introduce a notion of regions. For userspace for now it's just a new
structure called struct io_uring_region_desc which is supposed to
parameterise all such mapping / queue creations. A region either
represents a user provided chunk of memory, in which case the user_addr
field should point to it, or a request for the kernel to allocate the
memory, in which case the user would need to mmap it after using the
offset returned in the mmap_offset field. With a uniform userspace API
we can avoid additional boiler plate code and apply future optimisation
to all of them at once.

Internally, there is a new structure struct io_mapped_region holding all
relevant runtime information and some helpers to work with it. This
patch limits it to user provided regions.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0e6fe25818dfbaebd1bd90b870a6cac503fe1a24.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:58:34 -07:00
Pavel Begunkov
83e041522e io_uring: temporarily disable registered waits
Disable wait argument registration as it'll be replaced with a more
generic feature. We'll still need IORING_ENTER_EXT_ARG_REG parsing
in a few commits so leave it be.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/70b1d1d218c41ba77a76d1789c8641dab0b0563e.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:58:34 -07:00
Pavel Begunkov
3730aebbda io_uring: disable ENTER_EXT_ARG_REG for IOPOLL
IOPOLL doesn't use the extended arguments, no need for it to support
IORING_ENTER_EXT_ARG_REG. Let's disable it for IOPOLL, if anything it
leaves more space for future extensions.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a35ecd919dbdc17bd5b7932273e317832c531b45.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:58:34 -07:00
Pavel Begunkov
68685fa20e io_uring: fortify io_pin_pages with a warning
We're a bit too frivolous with types of nr_pages arguments, converting
it to long and back to int, passing an unsigned int pointer as an int
pointer and so on. Shouldn't cause any problem but should be carefully
reviewed, but until then let's add a WARN_ON_ONCE check to be more
confident callers don't pass poorely checked arguents.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d48e0c097cbd90fb47acaddb6c247596510d8cfc.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:58:34 -07:00
Al Viro
56cec28dc4 switch io_msg_ring() to CLASS(fd)
Use CLASS(fd) to get the file for sync message ring requests, rather
than open-code the file retrieval dance.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20241115034902.GP3387508@ZenIV
[axboe: make a more coherent commit message]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-15 09:55:54 -07:00
Christoph Hellwig
a3396b9999 block: add a rq_list type
Replace the semi-open coded request list helpers with a proper rq_list
type that mirrors the bio_list and has head and tail pointers.  Besides
better type safety this actually allows to insert at the tail of the
list, which will be useful soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241113152050.157179-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-13 12:04:58 -07:00
Al Viro
8e15e12d37 io_statx_prep(): use getname_uflags()
the only thing in flags getname_flags() ever cares about is
LOOKUP_EMPTY; anything else is none of its damn business.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-13 11:44:30 -05:00
Pavel Begunkov
b9d69371e8 io_uring: fix invalid hybrid polling ctx leaks
It has already allocated the ctx by the point where it checks the hybrid
poll configuration, plain return leaks the memory.

Fixes: 01ee194d1a ("io_uring: add support for hybrid IOPOLL")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Link: https://lore.kernel.org/r/b57f2608088020501d352fcdeebdb949e281d65b.1731468230.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-13 07:38:04 -07:00
Ming Lei
a43e236fb9 io_uring/uring_cmd: fix buffer index retrieval
Add back buffer index retrieval for IORING_URING_CMD_FIXED.

Reported-by: Guangwu Zhang <guazhang@redhat.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Fixes: b54a14041e ("io_uring/rsrc: add io_rsrc_node_lookup() helper")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Tested-by: Guangwu Zhang <guazhang@redhat.com>
Link: https://lore.kernel.org/r/20241111101318.1387557-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11 08:11:37 -07:00
Pavel Begunkov
df3b8ca604 io_uring/cmd: let cmds to know about dying task
When the taks that submitted a request is dying, a task work for that
request might get run by a kernel thread or even worse by a half
dismantled task. We can't just cancel the task work without running the
callback as the cmd might need to do some clean up, so pass a flag
instead. If set, it's not safe to access any task resources and the
callback is expected to cancel the cmd ASAP.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2024-11-11 14:34:21 +01:00
Ming Lei
039c878db7 io_uring/rsrc: add & apply io_req_assign_buf_node()
The following pattern becomes more and more:

+       io_req_assign_rsrc_node(&req->buf_node, node);
+       req->flags |= REQ_F_BUF_NODE;

so make it a helper, which is less fragile to use than above code, for
example, the BUF_NODE flag is even missed in current io_uring_cmd_prep().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241107110149.890530-4-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07 15:24:33 -07:00
Ming Lei
4f219fcce5 io_uring/rsrc: remove '->ctx_ptr' of 'struct io_rsrc_node'
Remove '->ctx_ptr' of 'struct io_rsrc_node', and add 'type' field,
meantime remove io_rsrc_node_type().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241107110149.890530-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07 15:24:33 -07:00
Ming Lei
0d98c50908 io_uring/rsrc: pass 'struct io_ring_ctx' reference to rsrc helpers
`io_rsrc_node` instance won't be shared among different io_uring ctxs,
and its allocation 'ctx' is always same with the user's 'ctx', so it is
safe to pass user 'ctx' reference to rsrc helpers. Even in io_clone_buffers(),
`io_rsrc_node` instance is allocated actually for destination io_uring_ctx.

Then io_rsrc_node_ctx() can be removed, and the 8 bytes `ctx` pointer will be
removed from `io_rsrc_node` in the following patch.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241107110149.890530-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07 15:24:33 -07:00
Nam Cao
fc9f59de26 io_uring: Switch to use hrtimer_setup_on_stack()
hrtimer_setup_on_stack() takes the callback function pointer as argument
and initializes the timer completely.

Replace hrtimer_init_on_stack() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/f0d4ac32ec4050710a656cee8385fa4427be33aa.1730386209.git.namcao@linutronix.de
2024-11-07 02:47:06 +01:00
Nam Cao
c95d36585b io_uring: Remove redundant hrtimer's callback function setup
The IORING_OP_TIMEOUT command uses hrtimer underneath. The timer's callback
function is setup in io_timeout(), and then the callback function is setup
again when the timer is rearmed.

Since the callback function is the same for both cases, the latter setup is
redundant, therefore remove it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk:
Link: https://lore.kernel.org/all/07b28dfd5691478a2d250f379c8b90dd37f9bb9a.1730386209.git.namcao@linutronix.de
2024-11-07 02:47:05 +01:00
Pavel Begunkov
af0a2ffef0 io_uring: avoid normal tw intermediate fallback
When a DEFER_TASKRUN io_uring is terminating it requeues deferred task
work items as normal tw, which can further fallback to kthread
execution. Avoid this extra step and always push them to the fallback
kthread.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d1cd472cec2230c66bd1c8d412a5833f0af75384.1730772720.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
6bf90bd8c5 io_uring/napi: add static napi tracking strategy
Add the static napi tracking strategy. That allows the user to manually
manage the napi ids list for busy polling, and eliminate the overhead of
dynamically updating the list from the fast path.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/96943de14968c35a5c599352259ad98f3c0770ba.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
71afd926f2 io_uring/napi: clean up __io_napi_do_busy_loop
__io_napi_do_busy_loop now requires to have loop_end in its parameters.
This makes the code cleaner and also has the benefit of removing a
branch since the only caller not passing NULL for loop_end_arg is also
setting the value conditionally.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/d5b9bb91b1a08fff50525e1c18d7b4709b9ca100.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
db1e1adf6f io_uring/napi: Use lock guards
Convert napi locks to use the shiny new Scope-Based Resource Management
machinery.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/2680ca47ee183cfdb89d1a40c84d349edeb620ab.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
a5e26f49fe io_uring/napi: improve __io_napi_add
1. move the sock->sk pointer validity test outside the function to
   avoid the function call overhead and to make the function more
   more reusable
2. change its name to __io_napi_add_id to be more precise about it is
   doing
3. return an error code to report errors

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/d637fa3b437d753c0f4e44ff6a7b5bf2c2611270.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
45b3941d09 io_uring/napi: fix io_napi_entry RCU accesses
correct 3 RCU structures modifications that were not using the RCU
functions to make their update.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/9f53b5169afa8c7bf3665a0b19dc2f7061173530.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Olivier Langlois
2f3cc8e441 io_uring/napi: protect concurrent io_napi_entry timeout accesses
io_napi_entry timeout value can be updated while accessed from the poll
functions.

Its concurrent accesses are wrapped with READ_ONCE()/WRITE_ONCE() macros
to avoid incorrect compiler optimizations.

Signed-off-by: Olivier Langlois <olivier@trillion01.com>
Link: https://lore.kernel.org/r/3de3087563cf98f75266fd9f85fdba063a8720db.1728828877.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Pavel Begunkov
483242714f io_uring: prevent speculating sq_array indexing
The SQ index array consists of user provided indexes, which io_uring
then uses to index the SQ, and so it's susceptible to speculation. For
all other queues io_uring tracks heads and tails in kernel, and they
shouldn't need any special care.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c6c7a25962924a55869e317e4fdb682dfdc6b279.1730687889.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Jens Axboe
b6f58a3f4a io_uring: move struct io_kiocb from task_struct to io_uring_task
Rather than store the task_struct itself in struct io_kiocb, store
the io_uring specific task_struct. The life times are the same in terms
of io_uring, and this avoids doing some dereferences through the
task_struct. For the hot path of putting local task references, we can
deref req->tctx instead, which we'll need anyway in that function
regardless of whether it's local or remote references.

This is mostly straight forward, except the original task PF_EXITING
check needs a bit of tweaking. task_work is _always_ run from the
originating task, except in the fallback case, where it's run from a
kernel thread. Replace the potentially racy (in case of fallback work)
checks for req->task->flags with current->flags. It's either the still
the original task, in which case PF_EXITING will be sane, or it has
PF_KTHREAD set, in which case it's fallback work. Both cases should
prevent moving forward with the given request.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Jens Axboe
6ed368cc5d io_uring: remove task ref helpers
They are only used right where they are defined, just open-code them
inside io_put_task().

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Jens Axboe
f03baece08 io_uring: move cancelations to be io_uring_task based
Right now the task_struct pointer is used as the key to match a task,
but in preparation for some io_kiocb changes, move it to using struct
io_uring_task instead. No functional changes intended in this patch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:38 -07:00
Jens Axboe
6f94cbc29a io_uring/rsrc: split io_kiocb node type assignments
Currently the io_rsrc_node assignment in io_kiocb is an array of two
pointers, as two nodes may be assigned to a request - one file node,
and one buffer node. However, the buffer node can co-exist with the
provided buffers, as currently it's not supported to use both provided
and registered buffers at the same time.

This crucially brings struct io_kiocb down to 4 cache lines again, as
before it spilled into the 5th cacheline.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:55:36 -07:00
Jens Axboe
6af82f7614 io_uring/rsrc: encode node type and ctx together
Rather than keep the type field separate rom ctx, use the fact that we
can encode up to 4 types of nodes in the LSB of the ctx pointer. Doesn't
reclaim any space right now on 64-bit archs, but it leaves a full int
for future use.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-06 13:54:15 -07:00
Al Viro
0158005aaa replace do_getxattr() with saner helpers.
similar to do_setxattr() in the previous commit...

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-06 12:59:39 -05:00
Al Viro
66d7ac6bdb replace do_setxattr() with saner helpers.
io_uring setxattr logics duplicates stuff from fs/xattr.c; provide
saner helpers (filename_setxattr() and file_setxattr() resp.) and
use them.

NB: putname(ERR_PTR()) is a no-op

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-06 12:59:39 -05:00
Al Viro
a10c4c5e01 new helper: import_xattr_name()
common logics for marshalling xattr names.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-06 12:59:39 -05:00
Christian Göttsche
537c76629d fs: rename struct xattr_ctx to kernel_xattr_ctx
Rename the struct xattr_ctx to increase distinction with the about to be
added user API struct xattr_args.

No functional change.

Suggested-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Link: https://lore.kernel.org/r/20240426162042.191916-2-cgoettsche@seltendoof.de
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-06 12:59:21 -05:00
Al Viro
b8cdd2530c io_[gs]etxattr_prep(): just use getname()
getname_flags(pathname, LOOKUP_FOLLOW) is obviously bogus - following
trailing symlinks has no impact on how to copy the pathname from userland...

Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-03 13:28:56 -05:00
Al Viro
6348be02ee fdget(), trivial conversions
fdget() is the first thing done in scope, all matching fdput() are
immediately followed by leaving the scope.

Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-11-03 01:28:06 -05:00
hexue
01ee194d1a io_uring: add support for hybrid IOPOLL
A new hybrid poll is implemented on the io_uring layer. Once an IO is
issued, it will not poll immediately, but rather block first and re-run
before IO complete, then poll to reap IO. While this poll method could
be a suboptimal solution when running on a single thread, it offers
performance lower than regular polling but higher than IRQ, and CPU
utilization is also lower than polling.

To use hybrid polling, the ring must be setup with both the
IORING_SETUP_IOPOLL and IORING_SETUP_HYBRID)IOPOLL flags set. Hybrid
polling has the same restrictions as IOPOLL, in that commands must
explicitly support it.

Signed-off-by: hexue <xue01.he@samsung.com>
Link: https://lore.kernel.org/r/20241101091957.564220-2-xue01.he@samsung.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
c1329532d5 io_uring/rsrc: allow cloning with node replacements
Currently cloning a buffer table will fail if the destination already has
a table. But it should be possible to use it to replace existing elements.
Add a IORING_REGISTER_DST_REPLACE cloning flag, which if set, will allow
the destination to already having a buffer table. If that is the case,
then entries designated by offset + nr buffers will be replaced if they
already exist.

Note that it's allowed to use IORING_REGISTER_DST_REPLACE and not have
an existing table, in which case it'll work just like not having the
flag set and an empty table - it'll just assign the newly created table
for that case.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
b16e920a19 io_uring/rsrc: allow cloning at an offset
Right now buffer cloning is an all-or-nothing kind of thing - either the
whole table is cloned from a source to a destination ring, or nothing at
all.

However, it's not always desired to clone the whole thing. Allow for
the application to specify a source and destination offset, and a
number of buffers to clone. If the destination offset is non-zero, then
allocate sparse nodes upfront.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
d50f94d761 io_uring/rsrc: get rid of the empty node and dummy_ubuf
The empty node was used as a placeholder for a sparse entry, but it
didn't really solve any issues. The caller still has to check for
whether it's the empty node or not, it may as well just check for a NULL
return instead.

The dummy_ubuf was used for a sparse buffer entry, but NULL will serve
the same purpose there of ensuring an -EFAULT on attempted import.

Just use NULL for a sparse node, regardless of whether or not it's a
file or buffer resource.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
4007c3d8c2 io_uring/rsrc: add io_reset_rsrc_node() helper
Puts and reset an existing node in a slot, if one exists. Returns true
if a node was there, false if not. This helps cleanup some of the code
that does a lookup just to clear an existing node.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
5f3829fdd6 io_uring/filetable: kill io_reset_alloc_hint() helper
It's only used internally, and in one spot, just open-code ti.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
cb1717a7cd io_uring/filetable: remove io_file_from_index() helper
It's only used in fdinfo, nothing really gained from having this helper.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
b54a14041e io_uring/rsrc: add io_rsrc_node_lookup() helper
There are lots of spots open-coding this functionality, add a generic
helper that does the node lookup in a speculation safe way.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:30 -06:00
Jens Axboe
3597f2786b io_uring/rsrc: unify file and buffer resource tables
For files, there's nr_user_files/file_table/file_data, and buffers have
nr_user_bufs/user_bufs/buf_data. There's no reason why file_table and
file_data can't be the same thing, and ditto for the buffer side. That
gets rid of more io_ring_ctx state that's in two spots rather than just
being in one spot, as it should be. Put all the registered file data in
one locations, and ditto on the buffer front.

This also avoids having both io_rsrc_data->nodes being an allocated
array, and ->user_bufs[] or ->file_table.nodes. There's no reason to
have this information duplicated. Keep it in one spot, io_rsrc_data,
along with how many resources are available.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:45:23 -06:00
Jens Axboe
f38f284764 io_uring: only initialize io_kiocb rsrc_nodes when needed
Add the empty node initializing to the preinit part of the io_kiocb
allocation, and reset them if they have been used.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:44:30 -06:00
Jens Axboe
0701db7439 io_uring/rsrc: add an empty io_rsrc_node for sparse buffer entries
Rather than allocate an io_rsrc_node for an empty/sparse buffer entry,
add a const entry that can be used for that. This just needs checking
for writing the tag, and the put check needs to check for that sparse
node rather than NULL for validity.

This avoids allocating rsrc nodes for sparse buffer entries.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:44:30 -06:00
Jens Axboe
fbbb8e991d io_uring/rsrc: get rid of io_rsrc_node allocation cache
It's not going to be needed in the fast path going forward, so kill it
off.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:44:30 -06:00
Jens Axboe
7029acd8a9 io_uring/rsrc: get rid of per-ring io_rsrc_node list
Work in progress, but get rid of the per-ring serialization of resource
nodes, like registered buffers and files. Main issue here is that one
node can otherwise hold up a bunch of other nodes from getting freed,
which is especially a problem for file resource nodes and networked
workloads where some descriptors may not see activity in a long time.

As an example, instantiate an io_uring ring fd and create a sparse
registered file table. Even 2 will do. Then create a socket and register
it as fixed file 0, F0. The number of open files in the app is now 5,
with 0/1/2 being the usual stdin/out/err, 3 being the ring fd, and 4
being the socket. Register this socket (eg "the listener") in slot 0 of
the registered file table. Now add an operation on the socket that uses
slot 0. Finally, loop N times, where each loop creates a new socket,
registers said socket as a file, then unregisters the socket, and
finally closes the socket. This is roughly similar to what a basic
accept loop would look like.

At the end of this loop, it's not unreasonable to expect that there
would still be 5 open files. Each socket created and registered in the
loop is also unregistered and closed. But since the listener socket
registered first still has references to its resource node due to still
being active, each subsequent socket unregistration is stuck behind it
for reclaim. Hence 5 + N files are still open at that point, where N is
awaiting the final put held up by the listener socket.

Rewrite the io_rsrc_node handling to NOT rely on serialization. Struct
io_kiocb now gets explicit resource nodes assigned, with each holding a
reference to the parent node. A parent node is either of type FILE or
BUFFER, which are the two types of nodes that exist. A request can have
two nodes assigned, if it's using both registered files and buffers.
Since request issue and task_work completion is both under the ring
private lock, no atomics are needed to handle these references. It's a
simple unlocked inc/dec. As before, the registered buffer or file table
each hold a reference as well to the registered nodes. Final put of the
node will remove the node and free the underlying resource, eg unmap the
buffer or put the file.

Outside of removing the stall in resource reclaim described above, it
has the following advantages:

1) It's a lot simpler than the previous scheme, and easier to follow.
   No need to specific quiesce handling anymore.

2) There are no resource node allocations in the fast path, all of that
   happens at resource registration time.

3) The structs related to resource handling can all get simplified
   quite a bit, like io_rsrc_node and io_rsrc_data. io_rsrc_put can
   go away completely.

4) Handling of resource tags is much simpler, and doesn't require
   persistent storage as it can simply get assigned up front at
   registration time. Just copy them in one-by-one at registration time
   and assign to the resource node.

The only real downside is that a request is now explicitly limited to
pinning 2 resources, one file and one buffer, where before just
assigning a resource node to a request would pin all of them. The upside
is that it's easier to follow now, as an individual resource is
explicitly referenced and assigned to the request.

With this in place, the above mentioned example will be using exactly 5
files at the end of the loop, not N.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-02 15:44:18 -06:00
Jens Axboe
1d60d74e85 io_uring/rw: fix missing NOWAIT check for O_DIRECT start write
When io_uring starts a write, it'll call kiocb_start_write() to bump the
super block rwsem, preventing any freezes from happening while that
write is in-flight. The freeze side will grab that rwsem for writing,
excluding any new writers from happening and waiting for existing writes
to finish. But io_uring unconditionally uses kiocb_start_write(), which
will block if someone is currently attempting to freeze the mount point.
This causes a deadlock where freeze is waiting for previous writes to
complete, but the previous writes cannot complete, as the task that is
supposed to complete them is blocked waiting on starting a new write.
This results in the following stuck trace showing that dependency with
the write blocked starting a new write:

task:fio             state:D stack:0     pid:886   tgid:886   ppid:876
Call trace:
 __switch_to+0x1d8/0x348
 __schedule+0x8e8/0x2248
 schedule+0x110/0x3f0
 percpu_rwsem_wait+0x1e8/0x3f8
 __percpu_down_read+0xe8/0x500
 io_write+0xbb8/0xff8
 io_issue_sqe+0x10c/0x1020
 io_submit_sqes+0x614/0x2110
 __arm64_sys_io_uring_enter+0x524/0x1038
 invoke_syscall+0x74/0x268
 el0_svc_common.constprop.0+0x160/0x238
 do_el0_svc+0x44/0x60
 el0_svc+0x44/0xb0
 el0t_64_sync_handler+0x118/0x128
 el0t_64_sync+0x168/0x170
INFO: task fsfreeze:7364 blocked for more than 15 seconds.
      Not tainted 6.12.0-rc5-00063-g76aaf945701c #7963

with the attempting freezer stuck trying to grab the rwsem:

task:fsfreeze        state:D stack:0     pid:7364  tgid:7364  ppid:995
Call trace:
 __switch_to+0x1d8/0x348
 __schedule+0x8e8/0x2248
 schedule+0x110/0x3f0
 percpu_down_write+0x2b0/0x680
 freeze_super+0x248/0x8a8
 do_vfs_ioctl+0x149c/0x1b18
 __arm64_sys_ioctl+0xd0/0x1a0
 invoke_syscall+0x74/0x268
 el0_svc_common.constprop.0+0x160/0x238
 do_el0_svc+0x44/0x60
 el0_svc+0x44/0xb0
 el0t_64_sync_handler+0x118/0x128
 el0t_64_sync+0x168/0x170

Fix this by having the io_uring side honor IOCB_NOWAIT, and only attempt a
blocking grab of the super block rwsem if it isn't set. For normal issue
where IOCB_NOWAIT would always be set, this returns -EAGAIN which will
have io_uring core issue a blocking attempt of the write. That will in
turn also get completions run, ensuring forward progress.

Since freezing requires CAP_SYS_ADMIN in the first place, this isn't
something that can be triggered by a regular user.

Cc: stable@vger.kernel.org # 5.10+
Reported-by: Peter Mann <peter.mann@sh.cz>
Link: https://lore.kernel.org/io-uring/38c94aec-81c9-4f62-b44e-1d87f5597644@sh.cz
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-31 08:21:02 -06:00
Jens Axboe
e410ffca58 io_uring/rsrc: kill io_charge_rsrc_node()
It's only used from __io_req_set_rsrc_node(), and it takes both the ctx
and node itself, while never using the ctx. Just open-code the basic
refs++ in __io_req_set_rsrc_node() instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
743fb58a35 io_uring/splice: open code 2nd direct file assignment
In preparation for not pinning the whole registered file table, open
code the second potential direct file assignment. This will be handled
by appropriate helpers in the future, for now just do it manually.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
aaa736b186 io_uring: specify freeptr usage for SLAB_TYPESAFE_BY_RCU io_kiocb cache
Doesn't matter right now as there's still some bytes left for it, but
let's prepare for the io_kiocb potentially growing and add a specific
freeptr offset for it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
ff1256b8f3 io_uring/rsrc: move struct io_fixed_file to rsrc.h header
There's no need for this internal structure to be visible, move it to
the private rsrc.h header instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
a85f31052b io_uring/nop: add support for testing registered files and buffers
Useful for testing performance/efficiency impact of registered files
and buffers, vs (particularly) non-registered files.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
aa00f67adc io_uring: add support for fixed wait regions
Generally applications have 1 or a few waits of waiting, yet they pass
in a struct io_uring_getevents_arg every time. This needs to get copied
and, in turn, the timeout value needs to get copied.

Rather than do this for every invocation, allow the application to
register a fixed set of wait regions that can simply be indexed when
asking the kernel to wait on events.

At ring setup time, the application can register a number of these wait
regions and initialize region/index 0 upfront:

	struct io_uring_reg_wait *reg;

	reg = io_uring_setup_reg_wait(ring, nr_regions, &ret);

	/* set timeout and mark as set, sigmask/sigmask_sz as needed */
	reg->ts.tv_sec = 0;
	reg->ts.tv_nsec = 100000;
	reg->flags = IORING_REG_WAIT_TS;

where nr_regions >= 1 && nr_regions <= PAGE_SIZE / sizeof(*reg). The
above initializes index 0, but 63 other regions can be initialized,
if needed. Now, instead of doing:

	struct __kernel_timespec timeout = { .tv_nsec = 100000, };

	io_uring_submit_and_wait_timeout(ring, &cqe, nr, &t, NULL);

to wait for events for each submit_and_wait, or just wait, operation, it
can just reference the above region at offset 0 and do:

	io_uring_submit_and_wait_reg(ring, &cqe, nr, 0);

to achieve the same goal of waiting 100usec without needing to copy
both struct io_uring_getevents_arg (24b) and struct __kernel_timeout
(16b) for each invocation. Struct io_uring_reg_wait looks as follows:

struct io_uring_reg_wait {
	struct __kernel_timespec	ts;
	__u32				min_wait_usec;
	__u32				flags;
	__u64				sigmask;
	__u32				sigmask_sz;
	__u32				pad[3];
	__u64				pad2[2];
};

embedding the timeout itself in the region, rather than passing it as
a pointer as well. Note that the signal mask is still passed as a
pointer, both for compatability reasons, but also because there doesn't
seem to be a lot of high frequency waits scenarios that involve setting
and resetting the signal mask for each wait.

The application is free to modify any region before a wait call, or it
can use keep multiple regions with different settings to avoid needing to
modify the same one for wait calls. Up to a page size of regions is mapped
by default, allowing PAGE_SIZE / 64 available regions for use.

The registered region must fit within a page. On a 4kb page size system,
that allows for 64 wait regions if a full page is used, as the size of
struct io_uring_reg_wait is 64b. The region registered must be aligned
to io_uring_reg_wait in size. It's valid to register less than 64
entries.

In network performance testing with zero-copy, this reduced the time
spent waiting on the TX side from 3.12% to 0.3% and the RX side from 4.4%
to 0.3%.

Wait regions are fixed for the lifetime of the ring - once registered,
they are persistent until the ring is torn down. The regions support
minimum wait timeout as well as the regular waits.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:28 -06:00
Jens Axboe
371b47da25 io_uring: change io_get_ext_arg() to use uaccess begin + end
In scenarios where a high frequency of wait events are seen, the copy
of the struct io_uring_getevents_arg is quite noticeable in the
profiles in terms of time spent. It can be seen as up to 3.5-4.5%.
Rewrite the copy-in logic, saving about 0.5% of the time.

Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
0a54a7dd0a io_uring: switch struct ext_arg from __kernel_timespec to timespec64
This avoids intermediate storage for turning a __kernel_timespec
user pointer into an on-stack struct timespec64, only then to turn it
into a ktime_t.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
b898b8c99e io_uring/sqpoll: wait on sqd->wait for thread parking
io_sqd_handle_event() just does a mutex unlock/lock dance when it's
supposed to park, somewhat relying on full ordering with the thread
trying to park it which does a similar unlock/lock dance on sqd->lock.
However, with adaptive spinning on mutexes, this can waste an awful
lot of time. Normally this isn't very noticeable, as parking and
unparking the thread isn't a common (or fast path) occurence. However,
in testing ring resizing, it's testing exactly that, as each resize
will require the SQPOLL to safely park and unpark.

Have io_sq_thread_park() explicitly wait on sqd->park_pending being
zero before attempting to grab the sqd->lock again.

In a resize test, this brings the runtime of SQPOLL down from about
60 seconds to a few seconds, just like the !SQPOLL tests. And saves
a ton of spinning time on the mutex, on both sides.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
79cfe9e59c io_uring/register: add IORING_REGISTER_RESIZE_RINGS
Once a ring has been created, the size of the CQ and SQ rings are fixed.
Usually this isn't a problem on the SQ ring side, as it merely controls
the available number of requests that can be submitted in a single
system call, and there's rarely a need to change that.

For the CQ ring, it's a different story. For most efficient use of
io_uring, it's important that the CQ ring never overflows. This means
that applications must size it for the worst case scenario, which can
be wasteful.

Add IORING_REGISTER_RESIZE_RINGS, which allows an application to resize
the existing rings. It takes a struct io_uring_params argument, the same
one which is used to setup the ring initially, and resizes rings
according to the sizes given.

Certain properties are always inherited from the original ring setup,
like SQE128/CQE32 and other setup options. The implementation only
allows flag associated with how the CQ ring is sized and clamped.

Existing unconsumed SQE and CQE entries are copied as part of the
process. If either the SQ or CQ resized destination ring cannot hold the
entries already present in the source rings, then the operation is failed
with -EOVERFLOW. Any register op holds ->uring_lock, which prevents new
submissions, and the internal mapping holds the completion lock as well
across moving CQ ring state.

To prevent races between mmap and ring resizing, add a mutex that's
solely used to serialize ring resize and mmap. mmap_sem can't be used
here, as as fork'ed process may be doing mmaps on the ring as well.
The ctx->resize_lock is held across mmap operations, and the resize
will grab it before swapping out the already mapped new data.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
d090bffab6 io_uring/memmap: explicitly return -EFAULT for mmap on NULL rings
The later mapping will actually check this too, but in terms of code
clarify, explicitly check for whether or not the rings and sqes are
valid during validation. That makes it explicit that if they are
non-NULL, they are valid and can get mapped.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
81d8191eb9 io_uring: abstract out a bit of the ring filling logic
Abstract out a io_uring_fill_params() helper, which fills out the
necessary bits of struct io_uring_params. Add it to io_uring.h as well,
in preparation for having another internal user of it.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
09d0a8ea7f io_uring: move max entry definition and ring sizing into header
In preparation for needing this somewhere else, move the definitions
for the maximum CQ and SQ ring size into io_uring.h. Make the
rings_size() helper available as well, and have it take just the setup
flags argument rather than the fill ring pointer. That's all that is
needed.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
882dec6c39 io_uring/net: clean up io_msg_copy_hdr
Put sr->umsg into a local variable, so it doesn't repeat "sr->umsg->"
for every field. It looks nicer, and likely without the patch it
compiles into a bunch of umsg memory reads.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/26c2f30b491ea7998bfdb5bb290662572a61064d.1729607201.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
5283878735 io_uring/net: don't alias send user pointer reads
We keep user pointers in an union, which could be a user buffer or a
user pointer to msghdr. What is confusing is that it potenitally reads
and assigns sqe->addr as one type but then uses it as another via the
union. Even more, it's not even consistent across copy and zerocopy
versions.

Make send and sendmsg setup helpers read sqe->addr and treat it as the
right type from the beginning. The end goal would be to get rid of
the use of struct io_sr_msg::umsg for send requests as we only need it
at the prep side.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/685d788605f5d78af18802fcabf61ba65cfd8002.1729607201.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
ad438d070a io_uring/net: don't store send address ptr
For non "msg" requests we copy the address at the prep stage and there
is no need to store the address user pointer long term. Pass the SQE
into io_send_setup(), let it parse it, and remove struct io_sr_msg addr
addr_len fields. It saves some space and also less confusing.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/db3dce544e17ca9d4b17d2506fbbac1da8a87824.1729607201.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
93db98f6f1 io_uring/net: split send and sendmsg prep helpers
A preparation patch splitting io_sendmsg_prep_setup into two separate
helpers for send and sendmsg variants.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1a2319471ba040e053b7f1d22f4af510d1118eca.1729607201.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
51c967c6c9 io_uring/net: move send zc fixed buffer import to issue path
Let's keep it close with the actual import, there's no reason to do this
on the prep side. With that, we can drop one of the branches checking
for whether or not IORING_RECVSEND_FIXED_BUF is set.

As a side-effect, get rid of req->imu usage.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
1caa00d6b6 io_uring: remove 'issue_flags' argument for io_req_set_rsrc_node()
All callers already hold the ring lock and hence are passing '0',
remove the argument and the conditional locking that it controlled.

Suggested-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
003f82b58c io_uring/rw: get rid of using req->imu
It's assigned in the same function that it's being used, get rid of
it. A local variable will do just fine.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
892d3e80e1 io_uring/uring_cmd: get rid of using req->imu
It's pretty pointless to use io_kiocb as intermediate storage for this,
so split the validity check and the actual usage. The resource node is
assigned upfront at prep time, to prevent it from going away. The actual
import is never called with the ctx->uring_lock held, so grab it for
the import.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
c919790060 io_uring/rsrc: don't assign bvec twice in io_import_fixed()
iter->bvec is already set to imu->bvec - remove the one dead assignment
and turn the other one into an addition instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
2946f08ae9 io_uring: clean up cqe trace points
We have too many helpers posting CQEs, instead of tracing completion
events before filling in a CQE and thus having to pass all the data,
set the CQE first, pass it to the tracing helper and let it extract
everything it needs.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b83c1ca9ee5aed2df0f3bb743bf5ed699cce4c86.1729267437.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
9b296c625a io_uring: static_key for !IORING_SETUP_NO_SQARRAY
IORING_SETUP_NO_SQARRAY should be preferred and used by default by
liburing, optimise flag checking in io_get_sqe() with a static key.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c164a48542fbb080115e2377ecf160c758562742.1729264988.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Pavel Begunkov
1e6e7602cc io_uring: kill io_llist_xchg
io_llist_xchg is only used to set the list to NULL, which can also be
done with llist_del_all(). Use the latter and kill io_llist_xchg.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d6765112680d2e86a58b76166b7513391ff4e5d7.1729264960.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
b6b3eb19dd io_uring: move cancel hash tables to kvmalloc/kvfree
Convert to using kvmalloc/kfree() for the hash tables, and while at it,
make it handle low memory situations better.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
8abf47a8d6 io_uring/cancel: get rid of init_hash_table() helper
All it does is initialize the lists, just move the INIT_HLIST_HEAD()
into the one caller.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
ba4366f57b io_uring/poll: get rid of per-hashtable bucket locks
Any access to the table is protected by ctx->uring_lock now anyway, the
per-bucket locking doesn't buy us anything.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
879ba46a38 io_uring/poll: get rid of io_poll_tw_hash_eject()
It serves no purposes anymore, all it does is delete the hash list
entry. task_work always has the ring locked.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
085268829b io_uring/poll: get rid of unlocked cancel hash
io_uring maintains two hash lists of inflight requests:

1) ctx->cancel_table_locked. This is used when the caller has the
   ctx->uring_lock held already. This is only an issue side parameter,
   as removal or task_work will always have it held.

2) ctx->cancel_table. This is used when the issuer does NOT have the
   ctx->uring_lock held, and relies on the table spinlocks for access.

However, it's pretty trivial to simply grab the lock in the one spot
where we care about it, for insertion. With that, we can kill the
unlocked table (and get rid of the _locked postfix for the other one).

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:27 -06:00
Jens Axboe
829ab73e7b io_uring/poll: remove 'ctx' argument from io_poll_req_delete()
It's always req->ctx being used anyway, having this as a separate
argument (that is then not even used) just makes it more confusing.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
a377132154 io_uring/msg_ring: add support for sending a sync message
Normally MSG_RING requires both a source and a destination ring. But
some users don't always have a ring avilable to send a message from, yet
they still need to notify a target ring.

Add support for using io_uring_register(2) without having a source ring,
using a file descriptor of -1 for that. Internally those are called
blind registration opcodes. Implement IORING_REGISTER_SEND_MSG_RING as a
blind opcode, which simply takes an sqe that the application can put on
the stack and use the normal liburing helpers to initialize it. Then the
app can call:

io_uring_register(-1, IORING_REGISTER_SEND_MSG_RING, &sqe, 1);

and get the same behavior in terms of the target, where a CQE is posted
with the details given in the sqe.

For now this takes a single sqe pointer argument, and hence arg must
be set to that, and nr_args must be 1. Could easily be extended to take
an array of sqes, but for now let's keep it simple.

Link: https://lore.kernel.org/r/20240924115932.116167-3-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
95d6c9229a io_uring/msg_ring: refactor a few helper functions
Mostly just to skip them taking an io_kiocb, rather just pass in the
ctx and io_msg directly.

In preparation for being able to issue a MSG_RING request without
having an io_kiocb. No functional changes in this patch.

Link: https://lore.kernel.org/r/20240924115932.116167-2-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
f4bb2f65bb io_uring/eventfd: move ctx->evfd_last_cq_tail into io_ev_fd
Everything else about the io_uring eventfd support is nicely kept
private to that code, except the cached_cq_tail tracking. With
everything else in place, move io_eventfd_flush_signal() to using
the ev_fd grab+release helpers, which then enables the direct use of
io_ev_fd for this tracking too.

Link: https://lore.kernel.org/r/20240921080307.185186-7-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
83a4f865e2 io_uring/eventfd: abstract out ev_fd grab + release helpers
In preparation for needing the ev_fd grabbing (and releasing) from
another path, abstract out two helpers for that.

Link: https://lore.kernel.org/r/20240921080307.185186-6-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
3ca5a35604 io_uring/eventfd: move trigger check into a helper
It's a bit hard to read what guards the triggering, move it into a
helper and add a comment explaining it too. This additionally moves
the ev_fd == NULL check in there as well.

Link: https://lore.kernel.org/r/20240921080307.185186-5-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
60c5f15800 io_uring/eventfd: move actual signaling part into separate helper
In preparation for using this from multiple spots, move the signaling
into a helper.

Link: https://lore.kernel.org/r/20240921080307.185186-4-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
3c90b80df5 io_uring/eventfd: check for the need to async notifier earlier
It's not necessary to do this post grabbing a reference. With that, we
can drop the out goto path as well.

Link: https://lore.kernel.org/r/20240921080307.185186-3-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
165126dc5e io_uring/eventfd: abstract out ev_fd put helper
We call this in two spot, have a helper for it. In preparation for
extending this part.

Link: https://lore.kernel.org/r/20240921080307.185186-2-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29 13:43:26 -06:00
Jens Axboe
dc7e76ba7a io_uring: IORING_OP_F[GS]ETXATTR is fine with REQ_F_FIXED_FILE
Rejection of IOSQE_FIXED_FILE combined with IORING_OP_[GS]ETXATTR
is fine - these do not take a file descriptor, so such combination
makes no sense.  The checks are misplaced, though - as it is, they
triggers on IORING_OP_F[GS]ETXATTR as well, and those do take
a file reference, no matter the origin.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-10-19 20:40:10 -04:00
Jens Axboe
ae6a888a43 io_uring/rw: fix wrong NOWAIT check in io_rw_init_file()
A previous commit improved how !FMODE_NOWAIT is dealt with, but
inadvertently negated a check whilst doing so. This caused -EAGAIN to be
returned from reading files with O_NONBLOCK set. Fix up the check for
REQ_F_SUPPORT_NOWAIT.

Reported-by: Julian Orth <ju.orth@gmail.com>
Link: https://github.com/axboe/liburing/issues/1270
Fixes: f7c9134385 ("io_uring/rw: allow pollable non-blocking attempts for !FMODE_NOWAIT")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-19 09:25:45 -06:00
Jens Axboe
8f7033aa40 io_uring/sqpoll: ensure task state is TASK_RUNNING when running task_work
When the sqpoll is exiting and cancels pending work items, it may need
to run task_work. If this happens from within io_uring_cancel_generic(),
then it may be under waiting for the io_uring_task waitqueue. This
results in the below splat from the scheduler, as the ring mutex may be
attempted grabbed while in a TASK_INTERRUPTIBLE state.

Ensure that the task state is set appropriately for that, just like what
is done for the other cases in io_run_task_work().

do not call blocking ops when !TASK_RUNNING; state=1 set at [<0000000029387fd2>] prepare_to_wait+0x88/0x2fc
WARNING: CPU: 6 PID: 59939 at kernel/sched/core.c:8561 __might_sleep+0xf4/0x140
Modules linked in:
CPU: 6 UID: 0 PID: 59939 Comm: iou-sqp-59938 Not tainted 6.12.0-rc3-00113-g8d020023b155 #7456
Hardware name: linux,dummy-virt (DT)
pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : __might_sleep+0xf4/0x140
lr : __might_sleep+0xf4/0x140
sp : ffff80008c5e7830
x29: ffff80008c5e7830 x28: ffff0000d93088c0 x27: ffff60001c2d7230
x26: dfff800000000000 x25: ffff0000e16b9180 x24: ffff80008c5e7a50
x23: 1ffff000118bcf4a x22: ffff0000e16b9180 x21: ffff0000e16b9180
x20: 000000000000011b x19: ffff80008310fac0 x18: 1ffff000118bcd90
x17: 30303c5b20746120 x16: 74657320313d6574 x15: 0720072007200720
x14: 0720072007200720 x13: 0720072007200720 x12: ffff600036c64f0b
x11: 1fffe00036c64f0a x10: ffff600036c64f0a x9 : dfff800000000000
x8 : 00009fffc939b0f6 x7 : ffff0001b6327853 x6 : 0000000000000001
x5 : ffff0001b6327850 x4 : ffff600036c64f0b x3 : ffff8000803c35bc
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000e16b9180
Call trace:
 __might_sleep+0xf4/0x140
 mutex_lock+0x84/0x124
 io_handle_tw_list+0xf4/0x260
 tctx_task_work_run+0x94/0x340
 io_run_task_work+0x1ec/0x3c0
 io_uring_cancel_generic+0x364/0x524
 io_sq_thread+0x820/0x124c
 ret_from_fork+0x10/0x20

Cc: stable@vger.kernel.org
Fixes: af5d68f889 ("io_uring/sqpoll: manage task_work privately")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-17 08:38:04 -06:00