Commit Graph

382 Commits

Author SHA1 Message Date
Mike Marshall ec51f8ee1e aio: initialize kiocb private in case any filesystems expect it.
A recent optimization had left private uninitialized.

Fixes: 2bc4ca9bb6 ("aio: don't zero entire aio_kiocb aio_get_req()")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-06 08:04:22 -07:00
Linus Torvalds f346b0becb Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - large KASAN update to use arm's "software tag-based mode"

 - a few misc things

 - sh updates

 - ocfs2 updates

 - just about all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (167 commits)
  kernel/fork.c: mark 'stack_vm_area' with __maybe_unused
  memcg, oom: notify on oom killer invocation from the charge path
  mm, swap: fix swapoff with KSM pages
  include/linux/gfp.h: fix typo
  mm/hmm: fix memremap.h, move dev_page_fault_t callback to hmm
  hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race
  hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
  memory_hotplug: add missing newlines to debugging output
  mm: remove __hugepage_set_anon_rmap()
  include/linux/vmstat.h: remove unused page state adjustment macro
  mm/page_alloc.c: allow error injection
  mm: migrate: drop unused argument of migrate_page_move_mapping()
  blkdev: avoid migration stalls for blkdev pages
  mm: migrate: provide buffer_migrate_page_norefs()
  mm: migrate: move migrate_page_lock_buffers()
  mm: migrate: lock buffers before migrate_page_move_mapping()
  mm: migration: factor out code to compute expected number of page references
  mm, page_alloc: enable pcpu_drain with zone capability
  kmemleak: add config to select auto scan
  mm/page_alloc.c: don't call kasan_free_pages() at deferred mem init
  ...
2018-12-28 16:55:46 -08:00
Linus Torvalds 956eb6cb36 for-4.21/aio-20181221
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Merge tag 'for-4.21/aio-20181221' of git://git.kernel.dk/linux-block

Pull aio updates from Jens Axboe:
 "Flushing out pre-patches for the buffered/polled aio series. Some
  fixes in here, but also optimizations"

* tag 'for-4.21/aio-20181221' of git://git.kernel.dk/linux-block:
  aio: abstract out io_event filler helper
  aio: split out iocb copy from io_submit_one()
  aio: use iocb_put() instead of open coding it
  aio: only use blk plugs for > 2 depth submissions
  aio: don't zero entire aio_kiocb aio_get_req()
  aio: separate out ring reservation from req allocation
  aio: use assigned completion handler
2018-12-28 13:57:59 -08:00
Linus Torvalds 0e9da3fbf7 for-4.21/block-20181221
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Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main pull request for block/storage for 4.21.

  Larger than usual, it was a busy round with lots of goodies queued up.
  Most notable is the removal of the old IO stack, which has been a long
  time coming. No new features for a while, everything coming in this
  week has all been fixes for things that were previously merged.

  This contains:

   - Use atomic counters instead of semaphores for mtip32xx (Arnd)

   - Cleanup of the mtip32xx request setup (Christoph)

   - Fix for circular locking dependency in loop (Jan, Tetsuo)

   - bcache (Coly, Guoju, Shenghui)
      * Optimizations for writeback caching
      * Various fixes and improvements

   - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith)
      * host and target support for NVMe over TCP
      * Error log page support
      * Support for separate read/write/poll queues
      * Much improved polling
      * discard OOM fallback
      * Tracepoint improvements

   - lightnvm (Hans, Hua, Igor, Matias, Javier)
      * Igor added packed metadata to pblk. Now drives without metadata
        per LBA can be used as well.
      * Fix from Geert on uninitialized value on chunk metadata reads.
      * Fixes from Hans and Javier to pblk recovery and write path.
      * Fix from Hua Su to fix a race condition in the pblk recovery
        code.
      * Scan optimization added to pblk recovery from Zhoujie.
      * Small geometry cleanup from me.

   - Conversion of the last few drivers that used the legacy path to
     blk-mq (me)

   - Removal of legacy IO path in SCSI (me, Christoph)

   - Removal of legacy IO stack and schedulers (me)

   - Support for much better polling, now without interrupts at all.
     blk-mq adds support for multiple queue maps, which enables us to
     have a map per type. This in turn enables nvme to have separate
     completion queues for polling, which can then be interrupt-less.
     Also means we're ready for async polled IO, which is hopefully
     coming in the next release.

   - Killing of (now) unused block exports (Christoph)

   - Unification of the blk-rq-qos and blk-wbt wait handling (Josef)

   - Support for zoned testing with null_blk (Masato)

   - sx8 conversion to per-host tag sets (Christoph)

   - IO priority improvements (Damien)

   - mq-deadline zoned fix (Damien)

   - Ref count blkcg series (Dennis)

   - Lots of blk-mq improvements and speedups (me)

   - sbitmap scalability improvements (me)

   - Make core inflight IO accounting per-cpu (Mikulas)

   - Export timeout setting in sysfs (Weiping)

   - Cleanup the direct issue path (Jianchao)

   - Export blk-wbt internals in block debugfs for easier debugging
     (Ming)

   - Lots of other fixes and improvements"

* tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits)
  kyber: use sbitmap add_wait_queue/list_del wait helpers
  sbitmap: add helpers for add/del wait queue handling
  block: save irq state in blkg_lookup_create()
  dm: don't reuse bio for flushes
  nvme-pci: trace SQ status on completions
  nvme-rdma: implement polling queue map
  nvme-fabrics: allow user to pass in nr_poll_queues
  nvme-fabrics: allow nvmf_connect_io_queue to poll
  nvme-core: optionally poll sync commands
  block: make request_to_qc_t public
  nvme-tcp: fix spelling mistake "attepmpt" -> "attempt"
  nvme-tcp: fix endianess annotations
  nvmet-tcp: fix endianess annotations
  nvme-pci: refactor nvme_poll_irqdisable to make sparse happy
  nvme-pci: only set nr_maps to 2 if poll queues are supported
  nvmet: use a macro for default error location
  nvmet: fix comparison of a u16 with -1
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  ...
2018-12-28 13:19:59 -08:00
Linus Torvalds b12a9124ee y2038: more syscalls and cleanups
This concludes the main part of the system call rework for 64-bit time_t,
 which has spread over most of year 2018, the last six system calls being
 
  - ppoll
  - pselect6
  - io_pgetevents
  - recvmmsg
  - futex
  - rt_sigtimedwait
 
 As before, nothing changes for 64-bit architectures, while 32-bit
 architectures gain another entry point that differs only in the layout
 of the timespec structure. Hopefully in the next release we can wire up
 all 22 of those system calls on all 32-bit architectures, which gives
 us a baseline version for glibc to start using them.
 
 This does not include the clock_adjtime, getrusage/waitid, and
 getitimer/setitimer system calls. I still plan to have new versions
 of those as well, but they are not required for correct operation of
 the C library since they can be emulated using the old 32-bit time_t
 based system calls.
 
 Aside from the system calls, there are also a few cleanups here,
 removing old kernel internal interfaces that have become unused after
 all references got removed. The arch/sh cleanups are part of this,
 there were posted several times over the past year without a reaction
 from the maintainers, while the corresponding changes made it into all
 other architectures.
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Merge tag 'y2038-for-4.21' of ssh://gitolite.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 updates from Arnd Bergmann:
 "More syscalls and cleanups

  This concludes the main part of the system call rework for 64-bit
  time_t, which has spread over most of year 2018, the last six system
  calls being

    - ppoll
    - pselect6
    - io_pgetevents
    - recvmmsg
    - futex
    - rt_sigtimedwait

  As before, nothing changes for 64-bit architectures, while 32-bit
  architectures gain another entry point that differs only in the layout
  of the timespec structure. Hopefully in the next release we can wire
  up all 22 of those system calls on all 32-bit architectures, which
  gives us a baseline version for glibc to start using them.

  This does not include the clock_adjtime, getrusage/waitid, and
  getitimer/setitimer system calls. I still plan to have new versions of
  those as well, but they are not required for correct operation of the
  C library since they can be emulated using the old 32-bit time_t based
  system calls.

  Aside from the system calls, there are also a few cleanups here,
  removing old kernel internal interfaces that have become unused after
  all references got removed. The arch/sh cleanups are part of this,
  there were posted several times over the past year without a reaction
  from the maintainers, while the corresponding changes made it into all
  other architectures"

* tag 'y2038-for-4.21' of ssh://gitolite.kernel.org:/pub/scm/linux/kernel/git/arnd/playground:
  timekeeping: remove obsolete time accessors
  vfs: replace current_kernel_time64 with ktime equivalent
  timekeeping: remove timespec_add/timespec_del
  timekeeping: remove unused {read,update}_persistent_clock
  sh: remove board_time_init() callback
  sh: remove unused rtc_sh_get/set_time infrastructure
  sh: sh03: rtc: push down rtc class ops into driver
  sh: dreamcast: rtc: push down rtc class ops into driver
  y2038: signal: Add compat_sys_rt_sigtimedwait_time64
  y2038: signal: Add sys_rt_sigtimedwait_time32
  y2038: socket: Add compat_sys_recvmmsg_time64
  y2038: futex: Add support for __kernel_timespec
  y2038: futex: Move compat implementation into futex.c
  io_pgetevents: use __kernel_timespec
  pselect6: use __kernel_timespec
  ppoll: use __kernel_timespec
  signal: Add restore_user_sigmask()
  signal: Add set_user_sigmask()
2018-12-28 12:45:04 -08:00
Jan Kara ab41ee6879 mm: migrate: drop unused argument of migrate_page_move_mapping()
All callers of migrate_page_move_mapping() now pass NULL for 'head'
argument.  Drop it.

Link: http://lkml.kernel.org/r/20181211172143.7358-7-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:51 -08:00
Jens Axboe 875736bb3f aio: abstract out io_event filler helper
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:59 -07:00
Jens Axboe 88a6f18b95 aio: split out iocb copy from io_submit_one()
In preparation of handing in iocbs in a different fashion as well. Also
make it clear that the iocb being passed in isn't modified, by marking
it const throughout.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:59 -07:00
Jens Axboe 71ebc6fef0 aio: use iocb_put() instead of open coding it
Replace the percpu_ref_put() + kmem_cache_free() with a call to
iocb_put() instead.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe a79d40e9b0 aio: only use blk plugs for > 2 depth submissions
Plugging is meant to optimize submission of a string of IOs, if we don't
have more than 2 being submitted, don't bother setting up a plug.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe 2bc4ca9bb6 aio: don't zero entire aio_kiocb aio_get_req()
It's 192 bytes, fairly substantial. Most items don't need to be cleared,
especially not upfront. Clear the ones we do need to clear, and leave
the other ones for setup when the iocb is prepared and submitted.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Christoph Hellwig 432c79978c aio: separate out ring reservation from req allocation
This is in preparation for certain types of IO not needing a ring
reserveration.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe bc9bff6162 aio: use assigned completion handler
We know this is a read/write request, but in preparation for
having different kinds of those, ensure that we call the assigned
handler instead of assuming it's aio_complete_rq().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-18 08:29:58 -07:00
Jens Axboe 4b92543282 Merge branch 'for-4.21/block' into for-4.21/aio
* for-4.21/block: (351 commits)
  blk-mq: enable IO poll if .nr_queues of type poll > 0
  blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight()
  blk-mq: skip zero-queue maps in blk_mq_map_swqueue
  block: fix blk-iolatency accounting underflow
  blk-mq: fix dispatch from sw queue
  block: mq-deadline: Fix write completion handling
  nvme-pci: don't share queue maps
  blk-mq: only dispatch to non-defauly queue maps if they have queues
  blk-mq: export hctx->type in debugfs instead of sysfs
  blk-mq: fix allocation for queue mapping table
  blk-wbt: export internal state via debugfs
  blk-mq-debugfs: support rq_qos
  block: update sysfs documentation
  block: loop: check error using IS_ERR instead of IS_ERR_OR_NULL in loop_add()
  aoe: add __exit annotation
  block: clear REQ_HIPRI if polling is not supported
  blk-mq: replace and kill blk_mq_request_issue_directly
  blk-mq: issue directly with bypass 'false' in blk_mq_sched_insert_requests
  blk-mq: refactor the code of issue request directly
  block: remove the bio_integrity_advance export
  ...
2018-12-18 08:29:53 -07:00
Linus Torvalds 380ef2c9ad for-linus-20181214
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Merge tag 'for-linus-20181214' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Three small fixes for this week. contains:

   - spectre indexing fix for aio (Jeff)

   - fix for the previous zeroing bio fix, we don't need it for user
     mapped pages, and in fact it breaks some applications if we do
     (Keith)

   - allocation failure fix for null_blk with zoned (Shin'ichiro)"

* tag 'for-linus-20181214' of git://git.kernel.dk/linux-block:
  block: Fix null_blk_zoned creation failure with small number of zones
  aio: fix spectre gadget in lookup_ioctx
  block/bio: Do not zero user pages
2018-12-14 12:18:30 -08:00
Jeff Moyer a538e3ff9d aio: fix spectre gadget in lookup_ioctx
Matthew pointed out that the ioctx_table is susceptible to spectre v1,
because the index can be controlled by an attacker.  The below patch
should mitigate the attack for all of the aio system calls.

Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-11 11:45:50 -07:00
Deepa Dinamani 7a35397f8c io_pgetevents: use __kernel_timespec
struct timespec is not y2038 safe.
struct __kernel_timespec is the new y2038 safe structure for all
syscalls that are using struct timespec.
Update io_pgetevents interfaces to use struct __kernel_timespec.

sigset_t also has different representations on 32 bit and 64 bit
architectures. Hence, we need to support the following different
syscalls:

New y2038 safe syscalls:
(Controlled by CONFIG_64BIT_TIME for 32 bit ABIs)

Native 64 bit(unchanged) and native 32 bit : sys_io_pgetevents
Compat : compat_sys_io_pgetevents_time64

Older y2038 unsafe syscalls:
(Controlled by CONFIG_32BIT_COMPAT_TIME for 32 bit ABIs)

Native 32 bit : sys_io_pgetevents_time32
Compat : compat_sys_io_pgetevents

Note that io_getevents syscalls do not have a y2038 safe solution.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:23:31 +01:00
Deepa Dinamani 854a6ed568 signal: Add restore_user_sigmask()
Refactor the logic to restore the sigmask before the syscall
returns into an api.
This is useful for versions of syscalls that pass in the
sigmask and expect the current->sigmask to be changed during
the execution and restored after the execution of the syscall.

With the advent of new y2038 syscalls in the subsequent patches,
we add two more new versions of the syscalls (for pselect, ppoll
and io_pgetevents) in addition to the existing native and compat
versions. Adding such an api reduces the logic that would need to
be replicated otherwise.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:22:53 +01:00
Deepa Dinamani ded653ccbe signal: Add set_user_sigmask()
Refactor reading sigset from userspace and updating sigmask
into an api.

This is useful for versions of syscalls that pass in the
sigmask and expect the current->sigmask to be changed during,
and restored after, the execution of the syscall.

With the advent of new y2038 syscalls in the subsequent patches,
we add two more new versions of the syscalls (for pselect, ppoll,
and io_pgetevents) in addition to the existing native and compat
versions. Adding such an api reduces the logic that would need to
be replicated otherwise.

Note that the calls to sigprocmask() ignored the return value
from the api as the function only returns an error on an invalid
first argument that is hardcoded at these call sites.
The updated logic uses set_current_blocked() instead.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-06 17:22:38 +01:00
Christoph Hellwig 154989e45f aio: clear IOCB_HIPRI
No one is going to poll for aio (yet), so we must clear the HIPRI
flag, as we would otherwise send it down the poll queues, where no
one will be polling for completions.

Signed-off-by: Christoph Hellwig <hch@lst.de>

IOCB_HIPRI, not RWF_HIPRI.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-04 09:39:06 -07:00
Jens Axboe 89d04ec349 Linux 4.20-rc5
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Merge tag 'v4.20-rc5' into for-4.21/block

Pull in v4.20-rc5, solving a conflict we'll otherwise get in aio.c and
also getting the merge fix that went into mainline that users are
hitting testing for-4.21/block and/or for-next.

* tag 'v4.20-rc5': (664 commits)
  Linux 4.20-rc5
  PCI: Fix incorrect value returned from pcie_get_speed_cap()
  MAINTAINERS: Update linux-mips mailing list address
  ocfs2: fix potential use after free
  mm/khugepaged: fix the xas_create_range() error path
  mm/khugepaged: collapse_shmem() do not crash on Compound
  mm/khugepaged: collapse_shmem() without freezing new_page
  mm/khugepaged: minor reorderings in collapse_shmem()
  mm/khugepaged: collapse_shmem() remember to clear holes
  mm/khugepaged: fix crashes due to misaccounted holes
  mm/khugepaged: collapse_shmem() stop if punched or truncated
  mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
  mm/huge_memory: splitting set mapping+index before unfreeze
  mm/huge_memory: rename freeze_page() to unmap_page()
  initramfs: clean old path before creating a hardlink
  kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
  psi: make disabling/enabling easier for vendor kernels
  proc: fixup map_files test on arm
  debugobjects: avoid recursive calls with kmemleak
  userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
  ...
2018-12-04 09:38:05 -07:00
Damien Le Moal 76dc891395 aio: Fix fallback I/O priority value
For cases when the application does not specify aio_reqprio for an aio,
fallback to use get_current_ioprio() to obtain the task I/O priority
last set using ioprio_set() rather than the hardcoded IOPRIO_CLASS_NONE
value.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-19 19:03:47 -07:00
Jens Axboe 53fffe29a9 aio: fix failure to put the file pointer
If the ioprio capability check fails, we return without putting
the file pointer.

Fixes: d9a08a9e61 ("fs: Add aio iopriority support")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-11-17 10:05:07 -05:00
Arnd Bergmann 9afc5eee65 y2038: globally rename compat_time to old_time32
Christoph Hellwig suggested a slightly different path for handling
backwards compatibility with the 32-bit time_t based system calls:

Rather than simply reusing the compat_sys_* entry points on 32-bit
architectures unchanged, we get rid of those entry points and the
compat_time types by renaming them to something that makes more sense
on 32-bit architectures (which don't have a compat mode otherwise),
and then share the entry points under the new name with the 64-bit
architectures that use them for implementing the compatibility.

The following types and interfaces are renamed here, and moved
from linux/compat_time.h to linux/time32.h:

old				new
---				---
compat_time_t			old_time32_t
struct compat_timeval		struct old_timeval32
struct compat_timespec		struct old_timespec32
struct compat_itimerspec	struct old_itimerspec32
ns_to_compat_timeval()		ns_to_old_timeval32()
get_compat_itimerspec64()	get_old_itimerspec32()
put_compat_itimerspec64()	put_old_itimerspec32()
compat_get_timespec64()		get_old_timespec32()
compat_put_timespec64()		put_old_timespec32()

As we already have aliases in place, this patch addresses only the
instances that are relevant to the system call interface in particular,
not those that occur in device drivers and other modules. Those
will get handled separately, while providing the 64-bit version
of the respective interfaces.

I'm not renaming the timex, rusage and itimerval structures, as we are
still debating what the new interface will look like, and whether we
will need a replacement at all.

This also doesn't change the names of the syscall entry points, which can
be done more easily when we actually switch over the 32-bit architectures
to use them, at that point we need to change COMPAT_SYSCALL_DEFINEx to
SYSCALL_DEFINEx with a new name, e.g. with a _time32 suffix.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-08-27 14:48:48 +02:00
Linus Torvalds f2be269897 Merge branch 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs aio updates from Al Viro:
 "Christoph's aio poll, saner this time around.

  This time it's pretty much local to fs/aio.c. Hopefully race-free..."

* 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: allow direct aio poll comletions for keyed wakeups
  aio: implement IOCB_CMD_POLL
  aio: add a iocb refcount
  timerfd: add support for keyed wakeups
2018-08-13 20:56:23 -07:00
Linus Torvalds a66b4cd1e7 Merge branch 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs open-related updates from Al Viro:

 - "do we need fput() or put_filp()" rules are gone - it's always fput()
   now. We keep track of that state where it belongs - in ->f_mode.

 - int *opened mess killed - in finish_open(), in ->atomic_open()
   instances and in fs/namei.c code around do_last()/lookup_open()/atomic_open().

 - alloc_file() wrappers with saner calling conventions are introduced
   (alloc_file_clone() and alloc_file_pseudo()); callers converted, with
   much simplification.

 - while we are at it, saner calling conventions for path_init() and
   link_path_walk(), simplifying things inside fs/namei.c (both on
   open-related paths and elsewhere).

* 'work.open3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  few more cleanups of link_path_walk() callers
  allow link_path_walk() to take ERR_PTR()
  make path_init() unconditionally paired with terminate_walk()
  document alloc_file() changes
  make alloc_file() static
  do_shmat(): grab shp->shm_file earlier, switch to alloc_file_clone()
  new helper: alloc_file_clone()
  create_pipe_files(): switch the first allocation to alloc_file_pseudo()
  anon_inode_getfile(): switch to alloc_file_pseudo()
  hugetlb_file_setup(): switch to alloc_file_pseudo()
  ocxlflash_getfile(): switch to alloc_file_pseudo()
  cxl_getfile(): switch to alloc_file_pseudo()
  ... and switch shmem_file_setup() to alloc_file_pseudo()
  __shmem_file_setup(): reorder allocations
  new wrapper: alloc_file_pseudo()
  kill FILE_{CREATED,OPENED}
  switch atomic_open() and lookup_open() to returning 0 in all success cases
  document ->atomic_open() changes
  ->atomic_open(): return 0 in all success cases
  get rid of 'opened' in path_openat() and the helpers downstream
  ...
2018-08-13 19:58:36 -07:00
Christoph Hellwig e8693bcfa0 aio: allow direct aio poll comletions for keyed wakeups
If we get a keyed wakeup for a aio poll waitqueue and wake can acquire the
ctx_lock without spinning we can just complete the iocb straight from the
wakeup callback to avoid a context switch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Avi Kivity <avi@scylladb.com>
2018-08-06 10:24:39 +02:00
Christoph Hellwig bfe4037e72 aio: implement IOCB_CMD_POLL
Simple one-shot poll through the io_submit() interface.  To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL.  It will poll the fd for the events specified in the
the first 32 bits of the aio_buf field of the iocb.

Unlike poll or epoll without EPOLLONESHOT this interface always works
in one shot mode, that is once the iocb is completed, it will have to be
resubmitted.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Avi Kivity <avi@scylladb.com>
2018-08-06 10:24:33 +02:00
Christoph Hellwig 9018ccc453 aio: add a iocb refcount
This is needed to prevent races caused by the way the ->poll API works.
To avoid introducing overhead for other users of the iocbs we initialize
it to zero and only do refcount operations if it is non-zero in the
completion path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Avi Kivity <avi@scylladb.com>
2018-08-06 10:24:28 +02:00
Linus Torvalds 165ea0d1c2 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Fix several places that screw up cleanups after failures halfway
  through opening a file (one open-coding filp_clone_open() and getting
  it wrong, two misusing alloc_file()). That part is -stable fodder from
  the 'work.open' branch.

  And Christoph's regression fix for uapi breakage in aio series;
  include/uapi/linux/aio_abi.h shouldn't be pulling in the kernel
  definition of sigset_t, the reason for doing so in the first place had
  been bogus - there's no need to expose struct __aio_sigset in
  aio_abi.h at all"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  aio: don't expose __aio_sigset in uapi
  ocxlflash_getfile(): fix double-iput() on alloc_file() failures
  cxl_getfile(): fix double-iput() on alloc_file() failures
  drm_mode_create_lease_ioctl(): fix open-coded filp_clone_open()
2018-07-22 12:04:51 -07:00
Christoph Hellwig 9ba546c019 aio: don't expose __aio_sigset in uapi
glibc uses a different defintion of sigset_t than the kernel does,
and the current version would pull in both.  To fix this just do not
expose the type at all - this somewhat mirrors pselect() where we
do not even have a type for the magic sigmask argument, but just
use pointer arithmetics.

Fixes: 7a074e96 ("aio: implement io_pgetevents")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Adrian Reber <adrian@lisas.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-17 23:26:58 -04:00
Al Viro d93aa9d82a new wrapper: alloc_file_pseudo()
takes inode, vfsmount, name, O_... flags and file_operations and
either returns a new struct file (in which case inode reference we
held is consumed) or returns ERR_PTR(), in which case no refcounts
are altered.

converted aio_private_file() and sock_alloc_file() to it

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:04:23 -04:00
Al Viro c9c554f214 alloc_file(): switch to passing O_... flags instead of FMODE_... mode
... so that it could set both ->f_flags and ->f_mode, without callers
having to set ->f_flags manually.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-07-12 10:02:57 -04:00
Linus Torvalds a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00
Christoph Hellwig 2739b807b0 aio: only return events requested in poll_mask() for IOCB_CMD_POLL
The ->poll_mask() operation has a mask of events that the caller
is interested in, but not all implementations might take it into
account.  Mask the return value to only the requested events,
similar to what the poll and epoll code does.

Reported-by: Avi Kivity <avi@scylladb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-06-14 20:08:14 -04:00
Adam Manzanares 9a6d9a62e0 fs: aio ioprio use ioprio_check_cap ret val
Previously the value was ignored.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-06-04 14:20:39 -04:00
Adam Manzanares d9a08a9e61 fs: Add aio iopriority support
This is the per-I/O equivalent of the ioprio_set system call.

When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the
newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field.

This patch depends on block: add ioprio_check_cap function.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-31 10:50:55 -04:00
Adam Manzanares fc28724d67 fs: Convert kiocb rw_hint from enum to u16
In order to avoid kiocb bloat for per command iopriority support, rw_hint
is converted from enum to a u16. Added a guard around ki_hint assignment.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-31 10:50:54 -04:00
Al Viro 1da92779e2 aio: sanitize the limit checking in io_submit(2)
as it is, the logics in native io_submit(2) is "if asked for
more than LONG_MAX/sizeof(pointer) iocbs to submit, don't
bother with more than LONG_MAX/sizeof(pointer)" (i.e.
512M requests on 32bit and 1E requests on 64bit) while
compat io_submit(2) goes with "stop after the first
PAGE_SIZE/sizeof(pointer) iocbs", i.e. 1K or so.  Which is
	* inconsistent
	* *way* too much in native case
	* possibly too little in compat one
and
	* wrong anyway, since the natural point where we
ought to stop bothering is ctx->nr_events

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:20:17 -04:00
Al Viro 67ba049f94 aio: fold do_io_submit() into callers
get rid of insane "copy array of 32bit pointers into an array of
native ones" glue.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:19:29 -04:00
Al Viro 95af8496ac aio: shift copyin of iocb into io_submit_one()
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:18:31 -04:00
Al Viro d2988bd412 aio_read_events_ring(): make a bit more readable
The logics for 'avail' is
	* not past the tail of cyclic buffer
	* no more than asked
	* not past the end of buffer
	* not past the end of a page

Unobfuscate the last part.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:18:17 -04:00
Al Viro 9061d14a8a aio: all callers of aio_{read,write,fsync,poll} treat 0 and -EIOCBQUEUED the same way
... so just make them return 0 when caller does not need to destroy iocb

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:17:40 -04:00
Al Viro 3c96c7f4ca aio: take list removal to (some) callers of aio_complete()
We really want iocb out of io_cancel(2) reach before we start tearing
it down.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-29 23:16:43 -04:00
Christoph Hellwig ac060cbaa8 aio: add missing break for the IOCB_CMD_FDSYNC case
Looks like this got lost in a merge.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-28 13:40:50 -04:00
Christoph Hellwig 1962da0d21 aio: try to complete poll iocbs without context switch
If we can acquire ctx_lock without spinning we can just remove our
iocb from the active_reqs list, and thus complete the iocbs from the
wakeup context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26 09:16:44 +02:00
Christoph Hellwig 2c14fa838c aio: implement IOCB_CMD_POLL
Simple one-shot poll through the io_submit() interface.  To poll for
a file descriptor the application should submit an iocb of type
IOCB_CMD_POLL.  It will poll the fd for the events specified in the
the first 32 bits of the aio_buf field of the iocb.

Unlike poll or epoll without EPOLLONESHOT this interface always works
in one shot mode, that is once the iocb is completed, it will have to be
resubmitted.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-26 09:16:44 +02:00
Christoph Hellwig 888933f8fd aio: simplify cancellation
With the current aio code there is no need for the magic KIOCB_CANCELLED
value, as a cancelation just kicks the driver to queue the completion
ASAP, with all actual completion handling done in another thread. Given
that both the completion path and cancelation take the context lock there
is no need for magic cmpxchg loops either.  If we remove iocbs from the
active list after calling ->ki_cancel (but with ctx_lock still held), we
can also rely on the invariant thay anything found on the list has a
->ki_cancel callback and can be cancelled, further simplifing the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26 09:16:44 +02:00
Christoph Hellwig f3a2752a43 aio: simplify KIOCB_KEY handling
No need to pass the key field to lookup_iocb to compare it with KIOCB_KEY,
as we can do that right after retrieving it from userspace.  Also move the
KIOCB_KEY definition to aio.c as it is an internal value not used by any
other place in the kernel.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-26 09:16:44 +02:00
Christoph Hellwig ed0d523adb Merge branch 'fixes' of https://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into aio-base 2018-05-26 09:16:25 +02:00
Al Viro 4faa99965e fix io_destroy()/aio_complete() race
If io_destroy() gets to cancelling everything that can be cancelled and
gets to kiocb_cancel() calling the function driver has left in ->ki_cancel,
it becomes vulnerable to a race with IO completion.  At that point req
is already taken off the list and aio_complete() does *NOT* spin until
we (in free_ioctx_users()) releases ->ctx_lock.  As the result, it proceeds
to kiocb_free(), freing req just it gets passed to ->ki_cancel().

Fix is simple - remove from the list after the call of kiocb_cancel().  All
instances of ->ki_cancel() already have to cope with the being called with
iocb still on list - that's what happens in io_cancel(2).

Cc: stable@kernel.org
Fixes: 0460fef2a9 "aio: use cancellation list lazily"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-23 22:53:22 -04:00
Al Viro baf10564fb aio: fix io_destroy(2) vs. lookup_ioctx() race
kill_ioctx() used to have an explicit RCU delay between removing the
reference from ->ioctx_table and percpu_ref_kill() dropping the refcount.
At some point that delay had been removed, on the theory that
percpu_ref_kill() itself contained an RCU delay.  Unfortunately, that was
the wrong kind of RCU delay and it didn't care about rcu_read_lock() used
by lookup_ioctx().  As the result, we could get ctx freed right under
lookup_ioctx().  Tejun has fixed that in a6d7cff472 ("fs/aio: Add explicit
RCU grace period when freeing kioctx"); however, that fix is not enough.

Suppose io_destroy() from one thread races with e.g. io_setup() from another;
CPU1 removes the reference from current->mm->ioctx_table[...] just as CPU2
has picked it (under rcu_read_lock()).  Then CPU1 proceeds to drop the
refcount, getting it to 0 and triggering a call of free_ioctx_users(),
which proceeds to drop the secondary refcount and once that reaches zero
calls free_ioctx_reqs().  That does
        INIT_RCU_WORK(&ctx->free_rwork, free_ioctx);
        queue_rcu_work(system_wq, &ctx->free_rwork);
and schedules freeing the whole thing after RCU delay.

In the meanwhile CPU2 has gotten around to percpu_ref_get(), bumping the
refcount from 0 to 1 and returned the reference to io_setup().

Tejun's fix (that queue_rcu_work() in there) guarantees that ctx won't get
freed until after percpu_ref_get().  Sure, we'd increment the counter before
ctx can be freed.  Now we are out of rcu_read_lock() and there's nothing to
stop freeing of the whole thing.  Unfortunately, CPU2 assumes that since it
has grabbed the reference, ctx is *NOT* going away until it gets around to
dropping that reference.

The fix is obvious - use percpu_ref_tryget_live() and treat failure as miss.
It's not costlier than what we currently do in normal case, it's safe to
call since freeing *is* delayed and it closes the race window - either
lookup_ioctx() comes before percpu_ref_kill() (in which case ctx->users
won't reach 0 until the caller of lookup_ioctx() drops it) or lookup_ioctx()
fails, ctx->users is unaffected and caller of lookup_ioctx() doesn't see
the object in question at all.

Cc: stable@kernel.org
Fixes: a6d7cff472 "fs/aio: Add explicit RCU grace period when freeing kioctx"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-21 14:30:11 -04:00
Christoph Hellwig 7a074e96de aio: implement io_pgetevents
This is the io_getevents equivalent of ppoll/pselect and allows to
properly mix signals and aio completions (especially with IOCB_CMD_POLL)
and atomically executes the following sequence:

	sigset_t origmask;

	pthread_sigmask(SIG_SETMASK, &sigmask, &origmask);
	ret = io_getevents(ctx, min_nr, nr, events, timeout);
	pthread_sigmask(SIG_SETMASK, &origmask, NULL);

Note that unlike many other signal related calls we do not pass a sigmask
size, as that would get us to 7 arguments, which aren't easily supported
by the syscall infrastructure.  It seems a lot less painful to just add a
new syscall variant in the unlikely case we're going to increase the
sigset size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:57:24 +02:00
Christoph Hellwig a3c0d439e4 aio: implement IOCB_CMD_FSYNC and IOCB_CMD_FDSYNC
Simple workqueue offload for now, but prepared for adding a real aio_fsync
method if the need arises.  Based on an earlier patch from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:57:24 +02:00
Christoph Hellwig 54843f875f aio: refactor read/write iocb setup
Don't reference the kiocb structure from the common aio code, and move
any use of it into helper specific to the read/write path.  This is in
preparation for aio_poll support that wants to use the space for different
fields.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:57:21 +02:00
Christoph Hellwig 92ce472856 aio: remove the extra get_file/fput pair in io_submit_one
If we release the lockdep write protection token before calling into
->write_iter and thus never access the file pointer after an -EIOCBQUEUED
return from ->write_iter or ->read_iter we don't need this extra
reference.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-02 19:56:30 +02:00
Christoph Hellwig 75321b50a3 aio: sanitize ki_list handling
Instead of handcoded non-null checks always initialize ki_list to an
empty list and use list_empty / list_empty_careful on it.  While we're
at it also error out on a double call to kiocb_set_cancel_fn instead
of ignoring it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:52:59 +02:00
Christoph Hellwig c213dc826c aio: remove an outdated BUG_ON and comment in aio_complete
These days we don't treat sync iocbs special in the aio completion code as
they never use it.  Remove the old comment and BUG_ON given that the
current definition of is_sync_kiocb makes it impossible to hit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:52:38 +02:00
Christoph Hellwig 01a658e1e9 aio: don't print the page size at boot time
The page size is in no way related to the aio code, and printing it in
the (debug) dmesg at every boot serves no purpose.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-05-02 19:48:36 +02:00
Tejun Heo f729863a8c fs/aio: Use rcu_work instead of explicit rcu and work item
Workqueue now has rcu_work.  Use it instead of open-coding rcu -> work
item bouncing.

Signed-off-by: Tejun Heo <tj@kernel.org>
2018-03-19 10:12:03 -07:00
Tejun Heo d0264c01e7 fs/aio: Use RCU accessors for kioctx_table->table[]
While converting ioctx index from a list to a table, db446a08c2
("aio: convert the ioctx list to table lookup v3") missed tagging
kioctx_table->table[] as an array of RCU pointers and using the
appropriate RCU accessors.  This introduces a small window in the
lookup path where init and access may race.

Mark kioctx_table->table[] with __rcu and use the approriate RCU
accessors when using the field.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Fixes: db446a08c2 ("aio: convert the ioctx list to table lookup v3")
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org # v3.12+
2018-03-14 12:10:17 -07:00
Tejun Heo a6d7cff472 fs/aio: Add explicit RCU grace period when freeing kioctx
While fixing refcounting, e34ecee2ae ("aio: Fix a trinity splat")
incorrectly removed explicit RCU grace period before freeing kioctx.
The intention seems to be depending on the internal RCU grace periods
of percpu_ref; however, percpu_ref uses a different flavor of RCU,
sched-RCU.  This can lead to kioctx being freed while RCU read
protected dereferences are still in progress.

Fix it by updating free_ioctx() to go through call_rcu() explicitly.

v2: Comment added to explain double bouncing.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Fixes: e34ecee2ae ("aio: Fix a trinity splat")
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org # v3.13+
2018-03-14 12:10:17 -07:00
Linus Torvalds 93f30c73ec Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull compat and uaccess updates from Al Viro:

 - {get,put}_compat_sigset() series

 - assorted compat ioctl stuff

 - more set_fs() elimination

 - a few more timespec64 conversions

 - several removals of pointless access_ok() in places where it was
   followed only by non-__ variants of primitives

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
  coredump: call do_unlinkat directly instead of sys_unlink
  fs: expose do_unlinkat for built-in callers
  ext4: take handling of EXT4_IOC_GROUP_ADD into a helper, get rid of set_fs()
  ipmi: get rid of pointless access_ok()
  pi433: sanitize ioctl
  cxlflash: get rid of pointless access_ok()
  mtdchar: get rid of pointless access_ok()
  r128: switch compat ioctls to drm_ioctl_kernel()
  selection: get rid of field-by-field copyin
  VT_RESIZEX: get rid of field-by-field copyin
  i2c compat ioctls: move to ->compat_ioctl()
  sched_rr_get_interval(): move compat to native, get rid of set_fs()
  mips: switch to {get,put}_compat_sigset()
  sparc: switch to {get,put}_compat_sigset()
  s390: switch to {get,put}_compat_sigset()
  ppc: switch to {get,put}_compat_sigset()
  parisc: switch to {get,put}_compat_sigset()
  get_compat_sigset()
  get rid of {get,put}_compat_itimerspec()
  io_getevents: Use timespec64 to represent timeouts
  ...
2017-11-17 11:54:55 -08:00
Mark Rutland 6aa7de0591 locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 11:01:08 +02:00
Deepa Dinamani fa2e62a540 io_getevents: Use timespec64 to represent timeouts
struct timespec is not y2038 safe. Use y2038 safe
struct timespec64 to represent timeouts.
The system call interface itself will be changed as
part of different series.

Timeouts will not really need more than 32 bits.
But, replacing these with timespec64 helps verification
of a y2038 safe kernel by getting rid of timespec
internally.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: linux-aio@kvack.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-19 17:55:59 -04:00
Linus Torvalds e253d98f5b Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull nowait read support from Al Viro:
 "Support IOCB_NOWAIT for buffered reads and block devices"

* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  block_dev: support RFW_NOWAIT on block device nodes
  fs: support RWF_NOWAIT for buffered reads
  fs: support IOCB_NOWAIT in generic_file_buffered_read
  fs: pass iocb to do_generic_file_read
2017-09-14 19:29:55 -07:00
Jérôme Glisse 2916ecc0f9 mm/migrate: new migrate mode MIGRATE_SYNC_NO_COPY
Introduce a new migration mode that allow to offload the copy to a device
DMA engine.  This changes the workflow of migration and not all
address_space migratepage callback can support this.

This is intended to be use by migrate_vma() which itself is use for thing
like HMM (see include/linux/hmm.h).

No additional per-filesystem migratepage testing is needed.  I disables
MIGRATE_SYNC_NO_COPY in all problematic migratepage() callback and i
added comment in those to explain why (part of this patch).  The commit
message is unclear it should say that any callback that wish to support
this new mode need to be aware of the difference in the migration flow
from other mode.

Some of these callbacks do extra locking while copying (aio, zsmalloc,
balloon, ...) and for DMA to be effective you want to copy multiple
pages in one DMA operations.  But in the problematic case you can not
easily hold the extra lock accross multiple call to this callback.

Usual flow is:

For each page {
 1 - lock page
 2 - call migratepage() callback
 3 - (extra locking in some migratepage() callback)
 4 - migrate page state (freeze refcount, update page cache, buffer
     head, ...)
 5 - copy page
 6 - (unlock any extra lock of migratepage() callback)
 7 - return from migratepage() callback
 8 - unlock page
}

The new mode MIGRATE_SYNC_NO_COPY:
 1 - lock multiple pages
For each page {
 2 - call migratepage() callback
 3 - abort in all problematic migratepage() callback
 4 - migrate page state (freeze refcount, update page cache, buffer
     head, ...)
} // finished all calls to migratepage() callback
 5 - DMA copy multiple pages
 6 - unlock all the pages

To support MIGRATE_SYNC_NO_COPY in the problematic case we would need a
new callback migratepages() (for instance) that deals with multiple
pages in one transaction.

Because the problematic cases are not important for current usage I did
not wanted to complexify this patchset even more for no good reason.

Link: http://lkml.kernel.org/r/20170817000548.32038-14-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Sherry Cheung <SCheung@nvidia.com>
Cc: Subhash Gutti <sgutti@nvidia.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:46 -07:00
Mauricio Faria de Oliveira 2a8a98673c fs: aio: fix the increment of aio-nr and counting against aio-max-nr
Currently, aio-nr is incremented in steps of 'num_possible_cpus() * 8'
for io_setup(nr_events, ..) with 'nr_events < num_possible_cpus() * 4':

    ioctx_alloc()
    ...
        nr_events = max(nr_events, num_possible_cpus() * 4);
        nr_events *= 2;
    ...
        ctx->max_reqs = nr_events;
    ...
        aio_nr += ctx->max_reqs;
    ....

This limits the number of aio contexts actually available to much less
than aio-max-nr, and is increasingly worse with greater number of CPUs.

For example, with 64 CPUs, only 256 aio contexts are actually available
(with aio-max-nr = 65536) because the increment is 512 in that scenario.

Note: 65536 [max aio contexts] / (64*4*2) [increment per aio context]
is 128, but make it 256 (double) as counting against 'aio-max-nr * 2':

    ioctx_alloc()
    ...
        if (aio_nr + nr_events > (aio_max_nr * 2UL) ||
        ...
            goto err_ctx;
    ...

This patch uses the original value of nr_events (from userspace) to
increment aio-nr and count against aio-max-nr, which resolves those.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Reported-by: Lekshmi C. Pillai <lekshmi.cpillai@in.ibm.com>
Tested-by: Lekshmi C. Pillai <lekshmi.cpillai@in.ibm.com>
Tested-by: Paul Nguyen <nguyenp@us.ibm.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
2017-09-07 12:28:28 -04:00
Christoph Hellwig 91f9943e1c fs: support RWF_NOWAIT for buffered reads
This is based on the old idea and code from Milosz Tanski.  With the aio
nowait code it becomes mostly trivial now.  Buffered writes continue to
return -EOPNOTSUPP if RWF_NOWAIT is passed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-04 19:04:23 -04:00
Jens Axboe 45d06cf701 fs: add O_DIRECT and aio support for sending down write life time hints
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:36 -06:00
Goldwyn Rodrigues b745fafaf7 fs: Introduce RWF_NOWAIT and FMODE_AIO_NOWAIT
RWF_NOWAIT informs kernel to bail out if an AIO request will block
for reasons such as file allocations, or a writeback triggered,
or would block while allocating requests while performing
direct I/O.

RWF_NOWAIT is translated to IOCB_NOWAIT for iocb->ki_flags.

FMODE_AIO_NOWAIT is a flag which identifies the file opened is capable
of returning -EAGAIN if the AIO call will block. This must be set by
supporting filesystems in the ->open() call.

Filesystems xfs, btrfs and ext4 would be supported in the following patches.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Goldwyn Rodrigues 9830f4be15 fs: Use RWF_* flags for AIO operations
aio_rw_flags is introduced in struct iocb (using aio_reserved1) which will
carry the RWF_* flags. We cannot use aio_flags because they are not
checked for validity which may break existing applications.

Note, the only place RWF_HIPRI comes in effect is dio_await_one().
All the rest of the locations, aio code return -EIOCBQUEUED before the
checks for RWF_HIPRI.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Linus Torvalds 1827adb11a Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched.h split-up from Ingo Molnar:
 "The point of these changes is to significantly reduce the
  <linux/sched.h> header footprint, to speed up the kernel build and to
  have a cleaner header structure.

  After these changes the new <linux/sched.h>'s typical preprocessed
  size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
  lines), which is around 40% faster to build on typical configs.

  Not much changed from the last version (-v2) posted three weeks ago: I
  eliminated quirks, backmerged fixes plus I rebased it to an upstream
  SHA1 from yesterday that includes most changes queued up in -next plus
  all sched.h changes that were pending from Andrew.

  I've re-tested the series both on x86 and on cross-arch defconfigs,
  and did a bisectability test at a number of random points.

  I tried to test as many build configurations as possible, but some
  build breakage is probably still left - but it should be mostly
  limited to architectures that have no cross-compiler binaries
  available on kernel.org, and non-default configurations"

* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
  sched/headers: Clean up <linux/sched.h>
  sched/headers: Remove #ifdefs from <linux/sched.h>
  sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
  sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
  sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
  sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
  sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
  sched/core: Remove unused prefetch_stack()
  sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
  sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
  sched/headers: Remove <linux/signal.h> from <linux/sched.h>
  sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
  sched/headers: Remove the runqueue_is_locked() prototype
  sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
  sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
  sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
  ...
2017-03-03 10:16:38 -08:00
Linus Torvalds 94e877d0fb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile two from Al Viro:

 - orangefs fix

 - series of fs/namei.c cleanups from me

 - VFS stuff coming from overlayfs tree

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  orangefs: Use RCU for destroy_inode
  vfs: use helper for calling f_op->fsync()
  mm: use helper for calling f_op->mmap()
  vfs: use helpers for calling f_op->{read,write}_iter()
  vfs: pass type instead of fn to do_{loop,iter}_readv_writev()
  vfs: extract common parts of {compat_,}do_readv_writev()
  vfs: wrap write f_ops with file_{start,end}_write()
  vfs: deny copy_file_range() for non regular files
  vfs: deny fallocate() on directory
  vfs: create vfs helper vfs_tmpfile()
  namei.c: split unlazy_walk()
  namei.c: fold the check for DCACHE_OP_REVALIDATE into d_revalidate()
  lookup_fast(): clean up the logics around the fallback to non-rcu mode
  namei: fold unlazy_link() into its sole caller
2017-03-02 15:20:00 -08:00
Al Viro 653a7746fa Merge remote-tracking branch 'ovl/for-viro' into for-linus
Overlayfs-related series from Miklos and Amir
2017-03-02 06:41:22 -05:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Mike Rapoport 897ab3e0c4 userfaultfd: non-cooperative: add event for memory unmaps
When a non-cooperative userfaultfd monitor copies pages in the
background, it may encounter regions that were already unmapped.
Addition of UFFD_EVENT_UNMAP allows the uffd monitor to track precisely
changes in the virtual memory layout.

Since there might be different uffd contexts for the affected VMAs, we
first should create a temporary representation for the unmap event for
each uffd context and then notify them one by one to the appropriate
userfault file descriptors.

The event notification occurs after the mmap_sem has been released.

[arnd@arndb.de: fix nommu build]
  Link: http://lkml.kernel.org/r/20170203165141.3665284-1-arnd@arndb.de
[mhocko@suse.com: fix nommu build]
  Link: http://lkml.kernel.org/r/20170202091503.GA22823@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1485542673-24387-3-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
Miklos Szeredi bb7462b6fd vfs: use helpers for calling f_op->{read,write}_iter()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-02-20 16:51:23 +01:00
Shaohua Li a12f1ae61c aio: fix lock dep warning
lockdep reports a warnning. file_start_write/file_end_write only
acquire/release the lock for regular files. So checking the files in aio
side too.

[  453.532141] ------------[ cut here ]------------
[  453.533011] WARNING: CPU: 1 PID: 1298 at ../kernel/locking/lockdep.c:3514 lock_release+0x434/0x670
[  453.533011] DEBUG_LOCKS_WARN_ON(depth <= 0)
[  453.533011] Modules linked in:
[  453.533011] CPU: 1 PID: 1298 Comm: fio Not tainted 4.9.0+ #964
[  453.533011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.0-1.fc24 04/01/2014
[  453.533011]  ffff8803a24b7a70 ffffffff8196cffb ffff8803a24b7ae8 0000000000000000
[  453.533011]  ffff8803a24b7ab8 ffffffff81091ee1 ffff8803a5dba700 00000dba00000008
[  453.533011]  ffffed0074496f59 ffff8803a5dbaf54 ffff8803ae0f8488 fffffffffffffdef
[  453.533011] Call Trace:
[  453.533011]  [<ffffffff8196cffb>] dump_stack+0x67/0x9c
[  453.533011]  [<ffffffff81091ee1>] __warn+0x111/0x130
[  453.533011]  [<ffffffff81091f97>] warn_slowpath_fmt+0x97/0xb0
[  453.533011]  [<ffffffff81091f00>] ? __warn+0x130/0x130
[  453.533011]  [<ffffffff8191b789>] ? blk_finish_plug+0x29/0x60
[  453.533011]  [<ffffffff811205d4>] lock_release+0x434/0x670
[  453.533011]  [<ffffffff8198af94>] ? import_single_range+0xd4/0x110
[  453.533011]  [<ffffffff81322195>] ? rw_verify_area+0x65/0x140
[  453.533011]  [<ffffffff813aa696>] ? aio_write+0x1f6/0x280
[  453.533011]  [<ffffffff813aa6c9>] aio_write+0x229/0x280
[  453.533011]  [<ffffffff813aa4a0>] ? aio_complete+0x640/0x640
[  453.533011]  [<ffffffff8111df20>] ? debug_check_no_locks_freed+0x1a0/0x1a0
[  453.533011]  [<ffffffff8114793a>] ? debug_lockdep_rcu_enabled.part.2+0x1a/0x30
[  453.533011]  [<ffffffff81147985>] ? debug_lockdep_rcu_enabled+0x35/0x40
[  453.533011]  [<ffffffff812a92be>] ? __might_fault+0x7e/0xf0
[  453.533011]  [<ffffffff813ac9bc>] do_io_submit+0x94c/0xb10
[  453.533011]  [<ffffffff813ac2ae>] ? do_io_submit+0x23e/0xb10
[  453.533011]  [<ffffffff813ac070>] ? SyS_io_destroy+0x270/0x270
[  453.533011]  [<ffffffff8111d7b3>] ? mark_held_locks+0x23/0xc0
[  453.533011]  [<ffffffff8100201a>] ? trace_hardirqs_on_thunk+0x1a/0x1c
[  453.533011]  [<ffffffff813acb90>] SyS_io_submit+0x10/0x20
[  453.533011]  [<ffffffff824f96aa>] entry_SYSCALL_64_fastpath+0x18/0xad
[  453.533011]  [<ffffffff81119190>] ? trace_hardirqs_off_caller+0xc0/0x110
[  453.533011] ---[ end trace b2fbe664d1cc0082 ]---

Cc: Dmitry Monakhov <dmonakhov@openvz.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-01-14 19:31:40 -05:00
Thomas Gleixner 2456e85535 ktime: Get rid of the union
ktime is a union because the initial implementation stored the time in
scalar nanoseconds on 64 bit machine and in a endianess optimized timespec
variant for 32bit machines. The Y2038 cleanup removed the timespec variant
and switched everything to scalar nanoseconds. The union remained, but
become completely pointless.

Get rid of the union and just keep ktime_t as simple typedef of type s64.

The conversion was done with coccinelle and some manual mopping up.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-25 17:21:22 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Al Viro c00d2c7e89 move aio compat to fs/aio.c
... and fix the minor buglet in compat io_submit() - native one
kills ioctx as cleanup when put_user() fails.  Get rid of
bogus compat_... in !CONFIG_AIO case, while we are at it - they
should simply fail with ENOSYS, same as for native counterparts.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 22:58:37 -05:00
Al Viro 450630975d don't open-code file_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-04 18:29:28 -05:00
Jan Kara 70fe2f4815 aio: fix freeze protection of aio writes
Currently we dropped freeze protection of aio writes just after IO was
submitted. Thus aio write could be in flight while the filesystem was
frozen and that could result in unexpected situation like aio completion
wanting to convert extent type on frozen filesystem. Testcase from
Dmitry triggering this is like:

for ((i=0;i<60;i++));do fsfreeze -f /mnt ;sleep 1;fsfreeze -u /mnt;done &
fio --bs=4k --ioengine=libaio --iodepth=128 --size=1g --direct=1 \
    --runtime=60 --filename=/mnt/file --name=rand-write --rw=randwrite

Fix the problem by dropping freeze protection only once IO is completed
in aio_complete().

Reported-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
[hch: forward ported on top of various VFS and aio changes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-30 13:09:42 -04:00
Christoph Hellwig 89319d31d2 fs: remove aio_run_iocb
Pass the ABI iocb structure to aio_setup_rw and let it handle the
non-vectored I/O case as well.  With that and a new helper for the AIO
return value handling we can now define new aio_read and aio_write
helpers that implement reads and writes in a self-contained way without
duplicating too much code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-30 13:09:42 -04:00
Christoph Hellwig 723c038475 fs: remove the never implemented aio_fsync file operation
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-30 13:09:42 -04:00
Christoph Hellwig 0b944d3a4b aio: hold an extra file reference over AIO read/write operations
Otherwise we might dereference an already freed file and/or inode
when aio_complete is called before we return from the read_iter or
write_iter method.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-30 13:09:42 -04:00
Rasmus Villemoes de04e76935 fs/aio.c: eliminate redundant loads in put_aio_ring_file
Using a local variable we can prevent gcc from reloading
aio_ring_file->f_inode->i_mapping twice, eliminating 2x2 dependent
loads.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:45:46 -04:00
Jann Horn 22f6b4d34f aio: mark AIO pseudo-fs noexec
This ensures that do_mmap() won't implicitly make AIO memory mappings
executable if the READ_IMPLIES_EXEC personality flag is set.  Such
behavior is problematic because the security_mmap_file LSM hook doesn't
catch this case, potentially permitting an attacker to bypass a W^X
policy enforced by SELinux.

I have tested the patch on my machine.

To test the behavior, compile and run this:

    #define _GNU_SOURCE
    #include <unistd.h>
    #include <sys/personality.h>
    #include <linux/aio_abi.h>
    #include <err.h>
    #include <stdlib.h>
    #include <stdio.h>
    #include <sys/syscall.h>

    int main(void) {
        personality(READ_IMPLIES_EXEC);
        aio_context_t ctx = 0;
        if (syscall(__NR_io_setup, 1, &ctx))
            err(1, "io_setup");

        char cmd[1000];
        sprintf(cmd, "cat /proc/%d/maps | grep -F '/[aio]'",
            (int)getpid());
        system(cmd);
        return 0;
    }

In the output, "rw-s" is good, "rwxs" is bad.

Signed-off-by: Jann Horn <jann@thejh.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-15 15:49:28 -07:00
Michal Hocko 013373e8b8 aio: make aio_setup_ring killable
aio_setup_ring waits for mmap_sem in writable mode.  If the waiting task
gets killed by the oom killer it would block oom_reaper from
asynchronous address space reclaim and reduce the chances of timely OOM
resolving.  Wait for the lock in the killable mode and return with EINTR
if the task got killed while waiting.  This will also expedite the
return to the userspace and do_exit.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Benamin LaHaise <bcrl@kvack.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-23 17:04:14 -07:00
Al Viro 2958ec177e aio: remove a pointless assignment
the value is never used after that point

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-03 19:51:33 -04:00
Oleg Nesterov 5477e70a64 mm: move ->mremap() from file_operations to vm_operations_struct
vma->vm_ops->mremap() looks more natural and clean in move_vma(), and this
way ->mremap() can have more users.  Say, vdso.

While at it, s/aio_ring_remap/aio_ring_mremap/.

Note: this is the minimal change before ->mremap() finds another user in
file_operations; this method should have more arguments, and it can be
used to kill arch_remap().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Linus Torvalds 4fc8adcfec Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull third hunk of vfs changes from Al Viro:
 "This contains the ->direct_IO() changes from Omar + saner
  generic_write_checks() + dealing with fcntl()/{read,write}() races
  (mirroring O_APPEND/O_DIRECT into iocb->ki_flags and instead of
  repeatedly looking at ->f_flags, which can be changed by fcntl(2),
  check ->ki_flags - which cannot) + infrastructure bits for dhowells'
  d_inode annotations + Christophs switch of /dev/loop to
  vfs_iter_write()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (30 commits)
  block: loop: switch to VFS ITER_BVEC
  configfs: Fix inconsistent use of file_inode() vs file->f_path.dentry->d_inode
  VFS: Make pathwalk use d_is_reg() rather than S_ISREG()
  VFS: Fix up debugfs to use d_is_dir() in place of S_ISDIR()
  VFS: Combine inode checks with d_is_negative() and d_is_positive() in pathwalk
  NFS: Don't use d_inode as a variable name
  VFS: Impose ordering on accesses of d_inode and d_flags
  VFS: Add owner-filesystem positive/negative dentry checks
  nfs: generic_write_checks() shouldn't be done on swapout...
  ocfs2: use __generic_file_write_iter()
  mirror O_APPEND and O_DIRECT into iocb->ki_flags
  switch generic_write_checks() to iocb and iter
  ocfs2: move generic_write_checks() before the alignment checks
  ocfs2_file_write_iter: stop messing with ppos
  udf_file_write_iter: reorder and simplify
  fuse: ->direct_IO() doesn't need generic_write_checks()
  ext4_file_write_iter: move generic_write_checks() up
  xfs_file_aio_write_checks: switch to iocb/iov_iter
  generic_write_checks(): drop isblk argument
  blkdev_write_iter: expand generic_file_checks() call in there
  ...
2015-04-16 23:27:56 -04:00
Linus Torvalds d82312c808 Merge branch 'for-4.1/core' of git://git.kernel.dk/linux-block
Pull block layer core bits from Jens Axboe:
 "This is the core pull request for 4.1.  Not a lot of stuff in here for
  this round, mostly little fixes or optimizations.  This pull request
  contains:

   - An optimization that speeds up queue runs on blk-mq, especially for
     the case where there's a large difference between nr_cpu_ids and
     the actual mapped software queues on a hardware queue.  From Chong
     Yuan.

   - Honor node local allocations for requests on legacy devices.  From
     David Rientjes.

   - Cleanup of blk_mq_rq_to_pdu() from me.

   - exit_aio() fixup from me, greatly speeding up exiting multiple IO
     contexts off exit_group().  For my particular test case, fio exit
     took ~6 seconds.  A typical case of both exposing RCU grace periods
     to user space, and serializing exit of them.

   - Make blk_mq_queue_enter() honor the gfp mask passed in, so we only
     wait if __GFP_WAIT is set.  From Keith Busch.

   - blk-mq exports and two added helpers from Mike Snitzer, which will
     be used by the dm-mq code.

   - Cleanups of blk-mq queue init from Wei Fang and Xiaoguang Wang"

* 'for-4.1/core' of git://git.kernel.dk/linux-block:
  blk-mq: reduce unnecessary software queue looping
  aio: fix serial draining in exit_aio()
  blk-mq: cleanup blk_mq_rq_to_pdu()
  blk-mq: put blk_queue_rq_timeout together in blk_mq_init_queue()
  block: remove redundant check about 'set->nr_hw_queues' in blk_mq_alloc_tag_set()
  block: allocate request memory local to request queue
  blk-mq: don't wait in blk_mq_queue_enter() if __GFP_WAIT isn't set
  blk-mq: export blk_mq_run_hw_queues
  blk-mq: add blk_mq_init_allocated_queue and export blk_mq_register_disk
2015-04-16 21:49:16 -04:00
Linus Torvalds fa927894bb Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second vfs update from Al Viro:
 "Now that net-next went in...  Here's the next big chunk - killing
  ->aio_read() and ->aio_write().

  There'll be one more pile today (direct_IO changes and
  generic_write_checks() cleanups/fixes), but I'd prefer to keep that
  one separate"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  ->aio_read and ->aio_write removed
  pcm: another weird API abuse
  infinibad: weird APIs switched to ->write_iter()
  kill do_sync_read/do_sync_write
  fuse: use iov_iter_get_pages() for non-splice path
  fuse: switch to ->read_iter/->write_iter
  switch drivers/char/mem.c to ->read_iter/->write_iter
  make new_sync_{read,write}() static
  coredump: accept any write method
  switch /dev/loop to vfs_iter_write()
  serial2002: switch to __vfs_read/__vfs_write
  ashmem: use __vfs_read()
  export __vfs_read()
  autofs: switch to __vfs_write()
  new helper: __vfs_write()
  switch hugetlbfs to ->read_iter()
  coda: switch to ->read_iter/->write_iter
  ncpfs: switch to ->read_iter/->write_iter
  net/9p: remove (now-)unused helpers
  p9_client_attach(): set fid->uid correctly
  ...
2015-04-15 13:22:56 -07:00
Jens Axboe dc48e56d76 aio: fix serial draining in exit_aio()
exit_aio() currently serializes killing io contexts. Each context
killing ends up having to do percpu_ref_kill(), which in turns has
to wait for an RCU grace period. This can take a long time, depending
on the number of contexts. And there's no point in doing them serially,
when we could be waiting for all of them in one fell swoop.

This patches makes my fio thread offload test case exit 0.2s instead
of almost 6s.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-15 11:17:23 -06:00
Linus Torvalds ca2ec32658 Merge branch 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro:
 "Part one:

   - struct filename-related cleanups

   - saner iov_iter_init() replacements (and switching the syscalls to
     use of those)

   - ntfs switch to ->write_iter() (Anton)

   - aio cleanups and splitting iocb into common and async parts
     (Christoph)

   - assorted fixes (me, bfields, Andrew Elble)

  There's a lot more, including the completion of switchover to
  ->{read,write}_iter(), d_inode/d_backing_inode annotations, f_flags
  race fixes, etc, but that goes after #for-davem merge.  David has
  pulled it, and once it's in I'll send the next vfs pull request"

* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (35 commits)
  sg_start_req(): use import_iovec()
  sg_start_req(): make sure that there's not too many elements in iovec
  blk_rq_map_user(): use import_single_range()
  sg_io(): use import_iovec()
  process_vm_access: switch to {compat_,}import_iovec()
  switch keyctl_instantiate_key_common() to iov_iter
  switch {compat_,}do_readv_writev() to {compat_,}import_iovec()
  aio_setup_vectored_rw(): switch to {compat_,}import_iovec()
  vmsplice_to_user(): switch to import_iovec()
  kill aio_setup_single_vector()
  aio: simplify arguments of aio_setup_..._rw()
  aio: lift iov_iter_init() into aio_setup_..._rw()
  lift iov_iter into {compat_,}do_readv_writev()
  NFS: fix BUG() crash in notify_change() with patch to chown_common()
  dcache: return -ESTALE not -EBUSY on distributed fs race
  NTFS: Version 2.1.32 - Update file write from aio_write to write_iter.
  VFS: Add iov_iter_fault_in_multipages_readable()
  drop bogus check in file_open_root()
  switch security_inode_getattr() to struct path *
  constify tomoyo_realpath_from_path()
  ...
2015-04-14 15:31:03 -07:00
Al Viro 2ba48ce513 mirror O_APPEND and O_DIRECT into iocb->ki_flags
... avoiding write_iter/fcntl races.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:30:22 -04:00
Al Viro dfea934575 Merge branch 'for-linus' into for-next 2015-04-11 22:29:51 -04:00
Al Viro 8436318205 ->aio_read and ->aio_write removed
no remaining users

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:43 -04:00