In io_uring_cancel_files(), after refcount_sub_and_test() leaves 0
req->refs, it calls io_put_req(), which would also put a ref. Call
io_free_req() instead.

Cc: stable@vger.kernel.org
Fixes: 2ca10259 ("io_uring: prune request from overflow list on flush")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When IORING_SETUP_SQPOLL is enabled, io_ring_ctx_wait_and_kill() will wait
for sq thread to idle by busy loop:

    while (ctx->sqo_thread && !wq_has_sleeper(&ctx->sqo_wait))
        cond_resched();

Above loop isn't very CPU friendly, it may introduce a short cpu burst on
the current cpu.

If ctx->refs is dying, we forbid sq_thread from submitting any further
SQEs. Instead they just get discarded when we exit.
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If the request is still hashed in io_async_task_func(), then it cannot
have been canceled and it's pointless to check. So save that check.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add IORING_OP_TEE implementing tee(2) support. Almost identical to
splice bits, but without offsets.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

export do_tee() for use in io_uring
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

req->flags stores all sqe->flags. After checking that sqe->flags are
valid set if IOSQE* flags, no need to double check it, just forward them
all.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_file_put() deals with flushing state's file refs, adding "state" to
its name makes it a bit clearer. Also, avoid double check of
state->file in __io_file_get() in some cases.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

A submission is "async" IIF it's done by SQPOLL thread. Instead of
passing @async flag into io_submit_sqes(), deduce it from ctx->flags.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We only need apoll in the one section, do the juggling with the work
restoration there. This removes a special case further down as well.

No functional changes in this patch.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

There's no point in using list_del_init() on entries that are going
away, and the associated lock is always used in process context so
let's not use the IRQ disabling+saving variant of the spinlock.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This new flag should be set/clear from the application to
disable/enable eventfd notifications when a request is completed
and queued to the CQ ring.

Before this patch, notifications were always sent if an eventfd is
registered, so IORING_CQ_EVENTFD_DISABLED is not set during the
initialization.

It will be up to the application to set the flag after initialization
if no notifications are required at the beginning.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This patch adds the new 'cq_flags' field that should be written by
the application and read by the kernel.

This new field is available to the userspace application through
'cq_off.flags'.
We are using 4-bytes previously reserved and set to zero. This means
that if the application finds this field to zero, then the new
functionality is not supported.

In the next patch we will introduce the first flag available.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Some file descriptors use separate waitqueues for their f_ops->poll()
handler, most commonly one for read and one for write. The io_uring
poll implementation doesn't work with that, as the 2nd poll_wait()
call will cause the io_uring poll request to -EINVAL.

This affects (at least) tty devices and /dev/random as well. This is a
big problem for event loops where some file descriptors work, and others
don't.

With this fix, io_uring handles multiple waitqueues.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We currently embed and queue a work item per fixed_file_ref_node that
we update, but if the workload does a lot of these, then the associated
kworker-events overhead can become quite noticeable.

Since we rarely need to wait on these, batch them at 1 second intervals
instead. If we do need to wait for them, we just flush the pending
delayed work.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We used to have three completions, now we just have two. With the two,
let's not allocate them dynamically, just embed then in the ctx and
name them appropriately.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Remove duplicate semicolon at the end of line in io_file_from_index()
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The "struct io_submit_state *state" parameter is not used, remove it.
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The attempt protecting us from closing the ring itself wasn't really
complete, and we actually don't need it. The referencing of requests
themselve, and the references they hold on the ring, ensures that the
life time of the ring is sane. With the check removed, we can also
remove the need to have the close operation fget() the file.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We currently make some guesses as when to open this fd, but in reality
we have no business (or need) to do so at all. In fact, it makes certain
things fail, like O_PATH.

Remove the fd lookup from these opcodes, we're just passing the 'fd' to
generic helpers anyway. With that, we can also remove the special casing
of fd values in io_req_needs_file(), and the 'fd_non_neg' check that
we have. And we can ensure that we only read sqe->fd once.

This fixes O_PATH usage with openat/openat2, and ditto statx path side
oddities.

Cc: stable@vger.kernel.org: # v5.6
Reported-by: Max Kellermann <mk@cm4all.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

do_splice() is used by io_uring, as will be do_tee(). Move f_mode
checks from sys_{splice,tee}() to do_{splice,tee}(), so they're
enforced for io_uring as well.

Fixes: 7d67af2c ("io_uring: add splice(2) support")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If copy_to_user() in io_uring_setup() failed, we'll leak many kernel
resources, which will be recycled until process terminates. This bug
can be reproduced by using mprotect to set params to PROT_READ. To fix
this issue, refactor io_uring_create() a bit to add a new 'struct
io_uring_params __user *params' parameter and move the copy_to_user()
in io_uring_setup() to io_uring_setup(), if copy_to_user() failed,
we can free kernel resource properly.
Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The prepare_to_wait() and finish_wait() calls in io_uring_cancel_files()
are mismatched. Currently I don't see any issues related this bug, just
find it by learning codes.
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull more btrfs fixes from David Sterba:
 "A few more stability fixes, minor build warning fixes and git url
  fixup:

   - fix partial loss of prealloc extent past i_size after fsync

   - fix potential deadlock due to wrong transaction handle passing via
     journal_info

   - fix gcc 4.8 struct intialization warning

   - update git URL in MAINTAINERS entry"

* tag 'for-5.7-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  MAINTAINERS: btrfs: fix git repo URL
  btrfs: fix gcc-4.8 build warning for struct initializer
  btrfs: transaction: Avoid deadlock due to bad initialization timing of fs_info::journal_info
  btrfs: fix partial loss of prealloc extent past i_size after fsync

Pull IOMMU fixes from Joerg Roedel:

 - Fix a memory leak when dev_iommu gets freed and a sub-pointer does
   not

 - Build dependency fixes for Mediatek, spapr_tce, and Intel IOMMU
   driver

 - Export iommu_group_get_for_dev() only for GPLed modules

 - Fix AMD IOMMU interrupt remapping when x2apic is enabled

 - Fix error path in the QCOM IOMMU driver probe function

* tag 'iommu-fixes-v5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/qcom: Fix local_base status check
  iommu: Properly export iommu_group_get_for_dev()
  iommu/vt-d: Use right Kconfig option name
  iommu/amd: Fix legacy interrupt remapping for x2APIC-enabled system
  iommu: spapr_tce: Disable compile testing to fix build on book3s_32 config
  iommu/mediatek: Fix MTK_IOMMU dependencies
  iommu: Fix the memory leak in dev_iommu_free()

The git repo listed for btrfs hasn't been updated in over a year.
List the current one instead.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Pull power management fixes from Rafael Wysocki:

 - prevent the intel_pstate driver from printing excessive diagnostic
   messages in some cases (Chris Wilson)

 - make the hibernation restore kernel freeze kernel threads as well as
   user space tasks (Dexuan Cui)

 - fix the ACPI device PM disagnostic messages to include the correct
   power state name (Kai-Heng Feng).

* tag 'pm-5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM: ACPI: Output correct message on target power state
  PM: hibernate: Freeze kernel threads in software_resume()
  cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once

* pm-cpufreq:
  cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once

* pm-sleep:
  PM: hibernate: Freeze kernel threads in software_resume()

Pull iomap fix from Darrick Wong:
 "Hoist the check for an unrepresentable FIBMAP return value into
  ioctl_fibmap.

  The internal kernel function can handle 64-bit values (and is needed
  to fix a regression on ext4 + jbd2). It is only the userspace ioctl
  that is so old that it cannot deal"

* tag 'iomap-5.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  fibmap: Warn and return an error in case of block > INT_MAX

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - fix handling of backchannel binding in BIND_CONN_TO_SESSION

  Bugfixes:
   - Fix a credential use-after-free issue in pnfs_roc()
   - Fix potential posix_acl refcnt leak in nfs3_set_acl
   - defer slow parts of rpc_free_client() to a workqueue
   - Fix an Oopsable race in __nfs_list_for_each_server()
   - Fix trace point use-after-free race
   - Regression: the RDMA client no longer responds to server disconnect
     requests
   - Fix return values of xdr_stream_encode_item_{present, absent}
   - _pnfs_return_layout() must always wait for layoutreturn completion

  Cleanups:
   - Remove unreachable error conditions"

* tag 'nfs-for-5.7-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: Fix a race in __nfs_list_for_each_server()
  NFSv4.1: fix handling of backchannel binding in BIND_CONN_TO_SESSION
  SUNRPC: defer slow parts of rpc_free_client() to a workqueue.
  NFSv4: Remove unreachable error condition due to rpc_run_task()
  SUNRPC: Remove unreachable error condition
  xprtrdma: Fix use of xdr_stream_encode_item_{present, absent}
  xprtrdma: Fix trace point use-after-free race
  xprtrdma: Restore wake-up-all to rpcrdma_cm_event_handler()
  nfs: Fix potential posix_acl refcnt leak in nfs3_set_acl
  NFS/pnfs: Fix a credential use-after-free issue in pnfs_roc()
  NFS/pnfs: Ensure that _pnfs_return_layout() waits for layoutreturn completion

Pull dmaengine fixes from Vinod Koul:
 "Core:
   - Documentation typo fixes
   - fix the channel indexes
   - dmatest: fixes for process hang and iterations

  Drivers:
   - hisilicon: build error fix without PCI_MSI
   - ti-k3: deadlock fix
   - uniphier-xdmac: fix for reg region
   - pch: fix data race
   - tegra: fix clock state"

* tag 'dmaengine-fix-5.7-rc4' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: dmatest: Fix process hang when reading 'wait' parameter
  dmaengine: dmatest: Fix iteration non-stop logic
  dmaengine: tegra-apb: Ensure that clock is enabled during of DMA synchronization
  dmaengine: fix channel index enumeration
  dmaengine: mmp_tdma: Reset channel error on release
  dmaengine: mmp_tdma: Do not ignore slave config validation errors
  dmaengine: pch_dma.c: Avoid data race between probe and irq handler
  dt-bindings: dma: uniphier-xdmac: switch to single reg region
  include/linux/dmaengine: Typos fixes in API documentation
  dmaengine: xilinx_dma: Add missing check for empty list
  dmaengine: ti: k3-psil: fix deadlock on error path
  dmaengine: hisilicon: Fix build error without PCI_MSI

Pull VFIO fixes from Alex Williamson:

 - copy_*_user validity check for new vfio_dma_rw interface (Yan Zhao)

 - Fix a potential math overflow (Yan Zhao)

 - Use follow_pfn() for calculating PFNMAPs (Sean Christopherson)

* tag 'vfio-v5.7-rc4' of git://github.com/awilliam/linux-vfio:
  vfio/type1: Fix VA->PA translation for PFNMAP VMAs in vaddr_get_pfn()
  vfio: avoid possible overflow in vfio_iommu_type1_pin_pages
  vfio: checking of validity of user vaddr in vfio_dma_rw

Pull arm64 fix from Catalin Marinas:
 "Add -fasynchronous-unwind-tables to the vDSO CFLAGS"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: vdso: Add -fasynchronous-unwind-tables to cflags

Pull io_uring fixes from Jens Axboe:

 - Fix for statx not grabbing the file table, making AT_EMPTY_PATH fail

 - Cover a few cases where async poll can handle retry, eliminating the
   need for an async thread

 - fallback request busy/free fix (Bijan)

 - syzbot reported SQPOLL thread exit fix for non-preempt (Xiaoguang)

 - Fix extra put of req for sync_file_range (Pavel)

 - Always punt splice async. We'll improve this for 5.8, but wanted to
   eliminate the inode mutex lock from the non-blocking path for 5.7
   (Pavel)

* tag 'io_uring-5.7-2020-05-01' of git://git.kernel.dk/linux-block:
  io_uring: punt splice async because of inode mutex
  io_uring: check non-sync defer_list carefully
  io_uring: fix extra put in sync_file_range()
  io_uring: use cond_resched() in io_ring_ctx_wait_and_kill()
  io_uring: use proper references for fallback_req locking
  io_uring: only force async punt if poll based retry can't handle it
  io_uring: enable poll retry for any file with ->read_iter / ->write_iter
  io_uring: statx must grab the file table for valid fd

Pull block fixes from Jens Axboe:
 "A few fixes for this release:

   - NVMe pull request from Christoph, with a single fix for a double
     free in the namespace error handling.

   - Kill the bd_openers check in blk_drop_partitions(), fixing a
     regression in this merge window (Christoph)"

* tag 'block-5.7-2020-05-01' of git://git.kernel.dk/linux-block:
  block: remove the bd_openers checks in blk_drop_partitions
  nvme: prevent double free in nvme_alloc_ns() error handling

Pull i2c fixes from Wolfram Sang:
 "Three driver bugfixes, and two reverts because the original patches
  revealed underlying problems which the Tegra guys are now working on"

* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: aspeed: Avoid i2c interrupt status clear race condition.
  i2c: amd-mp2-pci: Fix Oops in amd_mp2_pci_init() error handling
  Revert "i2c: tegra: Better handle case where CPU0 is busy for a long time"
  Revert "i2c: tegra: Synchronize DMA before termination"
  i2c: iproc: generate stop event for slave writes

Pull sound fixes from Takashi Iwai:
 "Just a collection of small fixes around this time:

   - One more try for fixing PCM OSS regression

   - HD-audio: a new quirk for Lenovo, the improved driver blacklisting,
     a lock fix in the minor error path, and a fix for the possible race
     at monitor notifiaction

   - USB-audio: a quirk ID fix, a fix for POD HD500 workaround"

* tag 'sound-5.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: usb-audio: Correct a typo of NuPrime DAC-10 USB ID
  ALSA: opti9xx: shut up gcc-10 range warning
  ALSA: hda/hdmi: fix without unlocked before return
  ALSA: hda/hdmi: fix race in monitor detection during probe
  ALSA: hda/realtek - Two front mics on a Lenovo ThinkCenter
  ALSA: line6: Fix POD HD500 audio playback
  ALSA: pcm: oss: Place the plugin buffer overflow checks correctly (for 5.7)
  ALSA: pcm: oss: Place the plugin buffer overflow checks correctly
  ALSA: hda: Match both PCI ID and SSID for driver blacklist

Pull drm fixes from Dave Airlie:
 "Regular scheduled fixes for graphics. Nothing to extreme bunch of
  amdgpu fixes, i915 and qxl fixes, along with some misc ones.

  All seems to be progressing normally.

  core:
   - EDID off by one DTD fix
   - DP mst write return code fix

  dma-buf:
   - fix SET_NAME ioctl uapi
   - doc fixes

  amdgpu:
   - Fix a green screen on resume issue
   - PM fixes for SR-IOV SDMA fix for navi
   - Renoir display fixes
   - Cursor and pageflip stuttering fixes
   - Misc additional display fixes
   - (uapi) Add additional DCC tiling flags for navi1x

  i915:
   - Fix selftest refcnt leak (Xiyu)
   - Fix gem vma lock (Chris)
   - Fix gt's i915_request.timeline acquire by checking if cacheline is
     valid (Chris)
   - Fix IRQ postinistall fault masks (Matt)

  qxl:
   - use after gree fix
   - fix lost kunmap
   - release leak fix

  virtio:
   - context destruction fix"

* tag 'drm-fixes-2020-05-01' of git://anongit.freedesktop.org/drm/drm: (26 commits)
  dma-buf: fix documentation build warnings
  drm/qxl: qxl_release use after free
  drm/qxl: lost qxl_bo_kunmap_atomic_page in qxl_image_init_helper()
  drm/i915: Use proper fault mask in interrupt postinstall too
  drm/amd/display: Use cursor locking to prevent flip delays
  drm/amd/display: Update downspread percent to match spreadsheet for DCN2.1
  drm/amd/display: Defer cursor update around VUPDATE for all ASIC
  drm/amd/display: fix rn soc bb update
  drm/amd/display: check if REFCLK_CNTL register is present
  drm/amdgpu: bump version for invalidate L2 before SDMA IBs
  drm/amdgpu: invalidate L2 before SDMA IBs (v2)
  drm/amdgpu: add tiling flags from Mesa
  drm/amd/powerplay: avoid using pm_en before it is initialized revised
  Revert "drm/amd/powerplay: avoid using pm_en before it is initialized"
  drm/qxl: qxl_release leak in qxl_hw_surface_alloc()
  drm/qxl: qxl_release leak in qxl_draw_dirty_fb()
  drm/virtio: only destroy created contexts
  drm/dp_mst: Fix drm_dp_send_dpcd_write() return code
  drm/i915/gt: Check cacheline is valid before acquiring
  drm/i915/gem: Hold obj->vma.lock over for_each_ggtt_vma()
  ...

Pull SCSI fixes from James Bottomley:
 "Four minor fixes: three in drivers and one in the core.

  The core one allows an additional state change that fixes a regression
  introduced by an update to the aacraid driver in the previous merge
  window"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: target/iblock: fix WRITE SAME zeroing
  scsi: qla2xxx: check UNLOADING before posting async work
  scsi: qla2xxx: set UNLOADING before waiting for session deletion
  scsi: core: Allow the state change from SDEV_QUIESCE to SDEV_BLOCK

Nonblocking do_splice() still may wait for some time on an inode mutex.
Let's play safe and always punt it async.
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>