linux.git/drivers/md/md.c, branch v6.10

md: Revert "md: Fix overflow in is_mddev_idle"

2024-05-07T13:34:08+00:00

This reverts commit 3f9f231236ce7e48780d8a4f1f8cb9fae2df1e4e.

Using 64bit for 'sync_io' is unnecessary from the gendisk side. This
overflow will not cause any functional impact, except for a UBSAN
warning. Solving this overflow requires introducing additional
calculations and checks which are not necessary. So just keep using
32bit for 'sync_io'.

Signed-off-by: Li Nan 
Link: https://lore.kernel.org/r/20240507023103.781816-1-linan666@huaweicloud.com
Signed-off-by: Jens Axboe

md: don't account sync_io if iostats of the disk is disabled

2024-04-09T04:15:46+00:00

If iostats is disabled, disk_stats will not be updated and
part_stat_read_accum() only returns a constant value. In this case,
continuing to count sync_io and to check is_mddev_idle() is no longer
meaningful.

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20240117031946.2324519-3-linan666@huaweicloud.com
Signed-off-by: Song Liu

md: Fix overflow in is_mddev_idle

2024-04-09T04:15:46+00:00

UBSAN reports this problem:

  UBSAN: Undefined behaviour in drivers/md/md.c:8175:15
  signed integer overflow:
  -2147483291 - 2072033152 cannot be represented in type 'int'
  Call trace:
   dump_backtrace+0x0/0x310
   show_stack+0x28/0x38
   dump_stack+0xec/0x15c
   ubsan_epilogue+0x18/0x84
   handle_overflow+0x14c/0x19c
   __ubsan_handle_sub_overflow+0x34/0x44
   is_mddev_idle+0x338/0x3d8
   md_do_sync+0x1bb8/0x1cf8
   md_thread+0x220/0x288
   kthread+0x1d8/0x1e0
   ret_from_fork+0x10/0x18

'curr_events' will overflow when stat accum or 'sync_io' is greater than
INT_MAX.

Fix it by changing sync_io, last_events and curr_events to 64bit.

Signed-off-by: Li Nan 
Reviewed-by: Yu Kuai 
Link: https://lore.kernel.org/r/20240117031946.2324519-2-linan666@huaweicloud.com
Signed-off-by: Song Liu

md: add check for sleepers in md_wakeup_thread()

2024-04-09T04:14:37+00:00

Check for sleeping thread before attempting its wake_up in
md_wakeup_thread() to avoid unnecessary spinlock contention.

With a 6.1 kernel, fio random read/write tests on many (>= 100)
virtual volumes, of 100 GiB each, on 3 md-raid5s on 8 SSDs each
(building a raid50), show by 3 to 4 % improved IOPS performance.

Signed-off-by: Florian-Ewald Mueller 
Reviewed-by: Yu Kuai 
Signed-off-by: Jack Wang 
Link: https://lore.kernel.org/r/20240327114022.74634-1-jinpu.wang@ionos.com
Signed-off-by: Song Liu

Merge tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux

2024-03-11T18:43:44+00:00

Pull block updates from Jens Axboe:

 - MD pull requests via Song:
      - Cleanup redundant checks (Yu Kuai)
      - Remove deprecated headers (Marc Zyngier, Song Liu)
      - Concurrency fixes (Li Lingfeng)
      - Memory leak fix (Li Nan)
      - Refactor raid1 read_balance (Yu Kuai, Paul Luse)
      - Clean up and fix for md_ioctl (Li Nan)
      - Other small fixes (Gui-Dong Han, Heming Zhao)
      - MD atomic limits (Christoph)

 - NVMe pull request via Keith:
      - RDMA target enhancements (Max)
      - Fabrics fixes (Max, Guixin, Hannes)
      - Atomic queue_limits usage (Christoph)
      - Const use for class_register (Ricardo)
      - Identification error handling fixes (Shin'ichiro, Keith)

 - Improvement and cleanup for cached request handling (Christoph)

 - Moving towards atomic queue limits. Core changes and driver bits so
   far (Christoph)

 - Fix UAF issues in aoeblk (Chun-Yi)

 - Zoned fix and cleanups (Damien)

 - s390 dasd cleanups and fixes (Jan, Miroslav)

 - Block issue timestamp caching (me)

 - noio scope guarding for zoned IO (Johannes)

 - block/nvme PI improvements (Kanchan)

 - Ability to terminate long running discard loop (Keith)

 - bdev revalidation fix (Li)

 - Get rid of old nr_queues hack for kdump kernels (Ming)

 - Support for async deletion of ublk (Ming)

 - Improve IRQ bio recycling (Pavel)

 - Factor in CPU capacity for remote vs local completion (Qais)

 - Add shared_tags configfs entry for null_blk (Shin'ichiro

 - Fix for a regression in page refcounts introduced by the folio
   unification (Tony)

 - Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid,
   Ricardo, Roman, Tang, Uwe)

* tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits)
  block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC
  block/swim: Convert to platform remove callback returning void
  cdrom: gdrom: Convert to platform remove callback returning void
  block: remove disk_stack_limits
  md: remove mddev->queue
  md: don't initialize queue limits
  md/raid10: use the atomic queue limit update APIs
  md/raid5: use the atomic queue limit update APIs
  md/raid1: use the atomic queue limit update APIs
  md/raid0: use the atomic queue limit update APIs
  md: add queue limit helpers
  md: add a mddev_is_dm helper
  md: add a mddev_add_trace_msg helper
  md: add a mddev_trace_remap helper
  bcache: move calculation of stripe_size and io_opt into bcache_device_init
  virtio_blk: Do not use disk_set_max_open/active_zones()
  aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts
  block: move capacity validation to blkpg_do_ioctl()
  block: prevent division by zero in blk_rq_stat_sum()
  drbd: atomically update queue limits in drbd_reconsider_queue_parameters
  ...

Merge tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2024-03-11T17:52:34+00:00

Pull block handle updates from Christian Brauner:
 "Last cycle we changed opening of block devices, and opening a block
  device would return a bdev_handle. This allowed us to implement
  support for restricting and forbidding writes to mounted block
  devices. It was accompanied by converting and adding helpers to
  operate on bdev_handles instead of plain block devices.

  That was already a good step forward but ultimately it isn't necessary
  to have special purpose helpers for opening block devices internally
  that return a bdev_handle.

  Fundamentally, opening a block device internally should just be
  equivalent to opening files. So now all internal opens of block
  devices return files just as a userspace open would. Instead of
  introducing a separate indirection into bdev_open_by_*() via struct
  bdev_handle bdev_file_open_by_*() is made to just return a struct
  file. Opening and closing a block device just becomes equivalent to
  opening and closing a file.

  This all works well because internally we already have a pseudo fs for
  block devices and so opening block devices is simple. There's a few
  places where we needed to be careful such as during boot when the
  kernel is supposed to mount the rootfs directly without init doing it.
  Here we need to take care to ensure that we flush out any asynchronous
  file close. That's what we already do for opening, unpacking, and
  closing the initramfs. So nothing new here.

  The equivalence of opening and closing block devices to regular files
  is a win in and of itself. But it also has various other advantages.
  We can remove struct bdev_handle completely. Various low-level helpers
  are now private to the block layer. Other helpers were simply
  removable completely.

  A follow-up series that is already reviewed build on this and makes it
  possible to remove bdev->bd_inode and allows various clean ups of the
  buffer head code as well. All places where we stashed a bdev_handle
  now just stash a file and use simple accessors to get to the actual
  block device which was already the case for bdev_handle"

* tag 'vfs-6.9.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
  block: remove bdev_handle completely
  block: don't rely on BLK_OPEN_RESTRICT_WRITES when yielding write access
  bdev: remove bdev pointer from struct bdev_handle
  bdev: make struct bdev_handle private to the block layer
  bdev: make bdev_{release, open_by_dev}() private to block layer
  bdev: remove bdev_open_by_path()
  reiserfs: port block device access to file
  ocfs2: port block device access to file
  nfs: port block device access to files
  jfs: port block device access to file
  f2fs: port block device access to files
  ext4: port block device access to file
  erofs: port device access to file
  btrfs: port device access to file
  bcachefs: port block device access to file
  target: port block device access to file
  s390: port block device access to file
  nvme: port block device access to file
  block2mtd: port device access to files
  bcache: port block device access to files
  ...

md: remove mddev->queue

2024-03-06T16:59:53+00:00

Just use the request_queue from the gendisk pointer in the relatively
few places that sill need it.

Signed-off-by: Christoph Hellwig 
Reviewed--by: Song Liu 
Tested-by: Song Liu 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20240303140150.5435-11-hch@lst.de

md: don't initialize queue limits

2024-03-06T16:59:53+00:00

Initial queue limits are now set from ->run.  Remove the superfluous
initialization in md_alloc and level_store.

Signed-off-by: Christoph Hellwig 
Reviewed--by: Song Liu 
Tested-by: Song Liu 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20240303140150.5435-10-hch@lst.de

md: add queue limit helpers

2024-03-06T16:59:53+00:00

Add a few helpers that wrap the block queue limits API for use in MD.

Signed-off-by: Christoph Hellwig 
Reviewed--by: Song Liu 
Tested-by: Song Liu 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20240303140150.5435-5-hch@lst.de

md: add a mddev_is_dm helper

2024-03-06T16:59:53+00:00

Add a helper to check for a DM-mapped MD device instead of using
the obfuscated ->gendisk or ->queue NULL checks.

Signed-off-by: Christoph Hellwig 
Reviewed--by: Song Liu 
Tested-by: Song Liu 
Signed-off-by: Song Liu 
Link: https://lore.kernel.org/r/20240303140150.5435-4-hch@lst.de