Commit Graph

262 Commits

Author SHA1 Message Date
Yuesong Li
00565cff01 dm: Convert to use ERR_CAST()
Use ERR_CAST() as it is designed for casting an error pointer to
another type.

This macro utilizes the __force and __must_check modifiers, which instruct
the compiler to verify for errors at the locations where it is employed.

Signed-off-by: Yuesong Li <liyuesong@vivo.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-09-02 11:41:11 +02:00
Christoph Hellwig
0a94a469a4 dm: stop using blk_limits_io_{min,opt}
Remove use of the blk_limits_io_{min,opt} and assign the values directly
to the queue_limits structure.  For the io_opt this is a completely
mechanical change, for io_min it removes flooring the limit to the
physical and logical block size in the particular caller.  But as
blk_validate_limits will do the same later when actually applying the
limits, there still is no change in overall behavior.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
2024-07-10 13:10:06 +02:00
Linus Torvalds
856726396d - Fix DM discard regressions due to DM core switching over to using
queue_limits_set() without DM core and targets first being updated
   to set (and stack) discard limits in terms of max_hw_discard_sectors
   and not max_discard_sectors.
 
 - Fix stable@ DM integrity discard support to set device's
   discard_granularity limit to the device's logical block size.
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Merge tag 'for-6.10/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - Fix DM discard regressions due to DM core switching over to using
   queue_limits_set() without DM core and targets first being updated to
   set (and stack) discard limits in terms of max_hw_discard_sectors and
   not max_discard_sectors

 - Fix stable@ DM integrity discard support to set device's
   discard_granularity limit to the device's logical block size

* tag 'for-6.10/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm: always manage discard support in terms of max_hw_discard_sectors
  dm-integrity: set discard_granularity to logical block size
2024-05-21 11:43:11 -07:00
Mike Snitzer
825d8bbd2f dm: always manage discard support in terms of max_hw_discard_sectors
Commit 4f563a6473 ("block: add a max_user_discard_sectors queue
limit") changed block core to set max_discard_sectors to:
 min(lim->max_hw_discard_sectors, lim->max_user_discard_sectors)

Since commit 1c0e720228 ("dm: use queue_limits_set") it was reported
dm-thinp was failing in a few fstests (generic/347 and generic/405)
with the first WARN_ON_ONCE in dm_cell_key_has_valid_range() being
reported, e.g.:
WARNING: CPU: 1 PID: 30 at drivers/md/dm-bio-prison-v1.c:128 dm_cell_key_has_valid_range+0x3d/0x50

blk_set_stacking_limits() sets max_user_discard_sectors to UINT_MAX,
so given how block core now sets max_discard_sectors (detailed above)
it follows that blk_stack_limits() stacks up the underlying device's
max_hw_discard_sectors and max_discard_sectors is set to match it. If
max_hw_discard_sectors exceeds dm's BIO_PRISON_MAX_RANGE, then
dm_cell_key_has_valid_range() will trigger the warning with:
WARN_ON_ONCE(key->block_end - key->block_begin > BIO_PRISON_MAX_RANGE)

Aside from this warning, the discard will fail.  Fix this and other DM
issues by governing discard support in terms of max_hw_discard_sectors
instead of max_discard_sectors.

Reported-by: Theodore Ts'o <tytso@mit.edu>
Fixes: 1c0e720228 ("dm: use queue_limits_set")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-05-20 15:51:19 -04:00
Christoph Hellwig
50bc215030 dm: use bio_list_merge_init
Use bio_list_merge_init instead of open coding bio_list_merge and
bio_list_init.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240328084147.2954434-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-01 11:53:37 -06:00
Mike Snitzer
fa34e5893f dm: update relevant MODULE_AUTHOR entries to latest dm-devel mailing list
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-02-20 14:22:55 -05:00
Mike Snitzer
47c00dcdd5 dm thin: add braces around conditional code that spans lines
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2024-02-20 13:37:31 -05:00
Linus Torvalds
6cdbb0907a - Update DM crypt to allocate compound pages if possible.
- Fix DM crypt target's crypt_ctr_cipher_new return value on invalid
   AEAD cipher.
 
 - Fix DM flakey testing target's write bio corruption feature to
   corrupt the data of a cloned bio instead of the original.
 
 - Add random_read_corrupt and random_write_corrupt features to DM
   flakey target.
 
 - Fix ABBA deadlock in DM thin metadata by resetting associated bufio
   client rather than destroying and recreating it.
 
 - A couple other small DM thinp cleanups.
 
 - Update DM core to support disabling block core IO stats accounting
   and optimize away code that isn't needed if stats are disabled.
 
 - Other small DM core cleanups.
 
 - Improve DM integrity target to not require so much memory on 32 bit
   systems. Also only allocate the recalculate buffer as needed (and
   increasingly reduce its size on allocation failure).
 
 - Update DM integrity to use %*ph for printing hexdump of a small
   buffer. Also update DM integrity documentation.
 
 - Various DM core ioctl interface hardening.  Now more careful about
   alignment of structures and processing of input passed to the kernel
   from userspace. Also disallow the creation of DM devices named
   "control", "." or ".."
 
 - Eliminate GFP_NOIO workarounds for __vmalloc and kvmalloc in DM
   core's ioctl and bufio code.
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Merge tag 'for-6.5/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Update DM crypt to allocate compound pages if possible

 - Fix DM crypt target's crypt_ctr_cipher_new return value on invalid
   AEAD cipher

 - Fix DM flakey testing target's write bio corruption feature to
   corrupt the data of a cloned bio instead of the original

 - Add random_read_corrupt and random_write_corrupt features to DM
   flakey target

 - Fix ABBA deadlock in DM thin metadata by resetting associated bufio
   client rather than destroying and recreating it

 - A couple other small DM thinp cleanups

 - Update DM core to support disabling block core IO stats accounting
   and optimize away code that isn't needed if stats are disabled

 - Other small DM core cleanups

 - Improve DM integrity target to not require so much memory on 32 bit
   systems. Also only allocate the recalculate buffer as needed (and
   increasingly reduce its size on allocation failure)

 - Update DM integrity to use %*ph for printing hexdump of a small
   buffer. Also update DM integrity documentation

 - Various DM core ioctl interface hardening. Now more careful about
   alignment of structures and processing of input passed to the kernel
   from userspace.

   Also disallow the creation of DM devices named "control", "." or ".."

 - Eliminate GFP_NOIO workarounds for __vmalloc and kvmalloc in DM
   core's ioctl and bufio code

* tag 'for-6.5/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (28 commits)
  dm: get rid of GFP_NOIO workarounds for __vmalloc and kvmalloc
  dm integrity: scale down the recalculate buffer if memory allocation fails
  dm integrity: only allocate recalculate buffer when needed
  dm integrity: reduce vmalloc space footprint on 32-bit architectures
  dm ioctl: Refuse to create device named "." or ".."
  dm ioctl: Refuse to create device named "control"
  dm ioctl: Avoid double-fetch of version
  dm ioctl: structs and parameter strings must not overlap
  dm ioctl: Avoid pointer arithmetic overflow
  dm ioctl: Check dm_target_spec is sufficiently aligned
  Documentation: dm-integrity: Document an example of how the tunables relate.
  Documentation: dm-integrity: Document default values.
  Documentation: dm-integrity: Document the meaning of "buffer".
  Documentation: dm-integrity: Fix minor grammatical error.
  dm integrity: Use %*ph for printing hexdump of a small buffer
  dm thin: disable discards for thin-pool if no_discard_passdown
  dm: remove stale/redundant dm_internal_{suspend,resume} prototypes in dm.h
  dm: skip dm-stats work in alloc_io() unless needed
  dm: avoid needless dm_io access if all IO accounting is disabled
  dm: support turning off block-core's io stats accounting
  ...
2023-06-30 12:16:00 -07:00
Linus Torvalds
a0433f8cae for-6.5/block-2023-06-23
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Merge tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull request via Keith:
      - Various cleanups all around (Irvin, Chaitanya, Christophe)
      - Better struct packing (Christophe JAILLET)
      - Reduce controller error logs for optional commands (Keith)
      - Support for >=64KiB block sizes (Daniel Gomez)
      - Fabrics fixes and code organization (Max, Chaitanya, Daniel
        Wagner)

 - bcache updates via Coly:
      - Fix a race at init time (Mingzhe Zou)
      - Misc fixes and cleanups (Andrea, Thomas, Zheng, Ye)

 - use page pinning in the block layer for dio (David)

 - convert old block dio code to page pinning (David, Christoph)

 - cleanups for pktcdvd (Andy)

 - cleanups for rnbd (Guoqing)

 - use the unchecked __bio_add_page() for the initial single page
   additions (Johannes)

 - fix overflows in the Amiga partition handling code (Michael)

 - improve mq-deadline zoned device support (Bart)

 - keep passthrough requests out of the IO schedulers (Christoph, Ming)

 - improve support for flush requests, making them less special to deal
   with (Christoph)

 - add bdev holder ops and shutdown methods (Christoph)

 - fix the name_to_dev_t() situation and use cases (Christoph)

 - decouple the block open flags from fmode_t (Christoph)

 - ublk updates and cleanups, including adding user copy support (Ming)

 - BFQ sanity checking (Bart)

 - convert brd from radix to xarray (Pankaj)

 - constify various structures (Thomas, Ivan)

 - more fine grained persistent reservation ioctl capability checks
   (Jingbo)

 - misc fixes and cleanups (Arnd, Azeem, Demi, Ed, Hengqi, Hou, Jan,
   Jordy, Li, Min, Yu, Zhong, Waiman)

* tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux: (266 commits)
  scsi/sg: don't grab scsi host module reference
  ext4: Fix warning in blkdev_put()
  block: don't return -EINVAL for not found names in devt_from_devname
  cdrom: Fix spectre-v1 gadget
  block: Improve kernel-doc headers
  blk-mq: don't insert passthrough request into sw queue
  bsg: make bsg_class a static const structure
  ublk: make ublk_chr_class a static const structure
  aoe: make aoe_class a static const structure
  block/rnbd: make all 'class' structures const
  block: fix the exclusive open mask in disk_scan_partitions
  block: add overflow checks for Amiga partition support
  block: change all __u32 annotations to __be32 in affs_hardblocks.h
  block: fix signed int overflow in Amiga partition support
  block: add capacity validation in bdev_add_partition()
  block: fine-granular CAP_SYS_ADMIN for Persistent Reservation
  block: disallow Persistent Reservation on partitions
  reiserfs: fix blkdev_put() warning from release_journal_dev()
  block: fix wrong mode for blkdev_get_by_dev() from disk_scan_partitions()
  block: document the holder argument to blkdev_get_by_path
  ...
2023-06-26 12:47:20 -07:00
Mike Snitzer
fa37564624 dm thin: disable discards for thin-pool if no_discard_passdown
Also rename disable_passdown_if_not_supported to
disable_discard_passdown_if_not_supported.

And fold passdown_enabled() into only caller.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-06-16 18:24:14 -04:00
Mike Snitzer
ef6953fb68 dm thin: update .io_hints methods to not require handling discards last
Removes assumptions about what might follow the discard setup code
(previously the code would return early if discards not enabled).

Makes it possible to add more capabilites to the end of each .io_hints
method (which is the natural thing to do when adding new features).

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-06-16 18:24:13 -04:00
Mike Snitzer
c0a7a0ac07 dm thin: remove return code variable in pool_map
Always returns DM_MAPIO_REMAPPED so no need for variable.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-06-16 18:24:13 -04:00
Mike Snitzer
722d908223 dm thin: fix issue_discard to pass GFP_NOIO to __blkdev_issue_discard
issue_discard() passes GFP_NOWAIT to __blkdev_issue_discard() despite
its code assuming bio_alloc() always succeeds.

Commit 3dba53a958 ("dm thin: use __blkdev_issue_discard for async
discard support") clearly shows where things went bad:

Before commit 3dba53a958, dm-thin.c's open-coded
__blkdev_issue_discard_async() properly handled using GFP_NOWAIT.
Unfortunately __blkdev_issue_discard() doesn't and it was missed
during review.

Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-06-15 12:46:59 -04:00
Christoph Hellwig
05bdb99653 block: replace fmode_t with a block-specific type for block open flags
The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE.  Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com>		[rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-12 08:04:05 -06:00
Mike Snitzer
3f8d3f5432 dm bio prison v1: add dm_cell_key_has_valid_range
Don't have bio_detain() BUG_ON if a dm_cell_key is beyond
BIO_PRISON_MAX_RANGE or spans a boundary.

Update dm-thin.c:build_key() to use dm_cell_key_has_valid_range() which
will do this checking without using BUG_ON. Also update
process_discard_bio() to check the discard bio that DM core passes in
(having first imposed max_discard_granularity based splitting).

dm_cell_key_has_valid_range() will merely WARN_ON_ONCE if it returns
false because if it does: it is programmer error that should be caught
with proper testing. So relax the BUG_ONs to be WARN_ON_ONCE.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-03-30 15:57:51 -04:00
Joe Thornber
e2dd8aca2d dm bio prison v1: improve concurrent IO performance
Split the bio prison into multiple regions, with a separate rbtree and
associated lock for each region.

To get fast bio prison locking and not damage the performance of
discards too much the bio-prison now stipulates that discards should
not cross a BIO_PRISON_MAX_RANGE boundary.

Because the range of a key (block_end - block_begin) must not exceed
BIO_PRISON_MAX_RANGE: break_up_discard_bio() now ensures the data
range reflected in PHYSICAL key doesn't exceed BIO_PRISON_MAX_RANGE.
And splitting the thin target's discards (handled with VIRTUAL key) is
achieved by updating dm-thin.c to set limits->max_discard_sectors in
terms of BIO_PRISON_MAX_RANGE _and_ setting the thin and thin-pool
targets' max_discard_granularity to true.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-03-30 15:57:51 -04:00
Joe Thornber
bb46c56165 dm thin: speed up cell_defer_no_holder()
Reduce the time that a spinlock is held in cell_defer_no_holder().

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-03-30 15:57:50 -04:00
Coly Li
9bbf5feecc dm thin: fix deadlock when swapping to thin device
This is an already known issue that dm-thin volume cannot be used as
swap, otherwise a deadlock may happen when dm-thin internal memory
demand triggers swap I/O on the dm-thin volume itself.

But thanks to commit a666e5c05e ("dm: fix deadlock when swapping to
encrypted device"), the limit_swap_bios target flag can also be used
for dm-thin to avoid the recursive I/O when it is used as swap.

Fix is to simply set ti->limit_swap_bios to true in both pool_ctr()
and thin_ctr().

In my test, I create a dm-thin volume /dev/vg/swap and use it as swap
device. Then I run fio on another dm-thin volume /dev/vg/main and use
large --blocksize to trigger swap I/O onto /dev/vg/swap.

The following fio command line is used in my test,
  fio --name recursive-swap-io --lockmem 1 --iodepth 128 \
     --ioengine libaio --filename /dev/vg/main --rw randrw \
    --blocksize 1M --numjobs 32 --time_based --runtime=12h

Without this fix, the whole system can be locked up within 15 seconds.

With this fix, there is no any deadlock or hung task observed after
2 hours of running fio.

Furthermore, if blocksize is changed from 1M to 128M, after around 30
seconds fio has no visible I/O, and the out-of-memory killer message
shows up in kernel message. After around 20 minutes all fio processes
are killed and the whole system is back to being alive.

This is exactly what is expected when recursive I/O happens on dm-thin
volume when it is used as swap.

Depends-on: a666e5c05e ("dm: fix deadlock when swapping to encrypted device")
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-03-06 16:37:06 -05:00
Mike Snitzer
e4f80303c2 dm thin: add cond_resched() to various workqueue loops
Otherwise on resource constrained systems these workqueues may be too
greedy.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-17 14:46:27 -05:00
Heinz Mauelshagen
774f13ac2b dm: declare variables static when sensible
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:07 -05:00
Heinz Mauelshagen
6a80803472 dm: avoid using symbolic permissions
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:07 -05:00
Heinz Mauelshagen
0ef0b4717a dm: add missing empty lines
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:06 -05:00
Heinz Mauelshagen
a4a82ce3d2 dm: correct block comments format.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:06 -05:00
Heinz Mauelshagen
255e264649 dm: address indent/space issues
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:06 -05:00
Heinz Mauelshagen
86a3238c7b dm: change "unsigned" to "unsigned int"
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:06 -05:00
Heinz Mauelshagen
3bd9400307 dm: add missing SPDX-License-Indentifiers
'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has
deprecated its use.

Suggested-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2023-02-14 14:23:06 -05:00
Linus Torvalds
8715c6d310 - Fix use-after-free races due to missing resource cleanup during DM
target destruction in DM targets: thin-pool, cache, integrity and
   clone.
 
 - Fix ABBA deadlocks in DM thin-pool and cache targets due to their
   use of a bufio client (that has a shrinker whose locking can cause
   the incorrect locking order).
 
 - Fix DM cache target to set its needs_check flag after first aborting
   the metadata (whereby using reset persistent-data objects to update
   the superblock with, otherwise the superblock update could be
   dropped due to aborting metadata).  This was found with
   code-inspection when comparing with the equivalent in DM thinp
   code.
 
 - Fix DM thin-pool's presume to continue resuming the device even if
   the pool in is fail mode -- otherwise bios may never be failed up
   the IO stack (which will prevent resetting the thin-pool target via
   table reload)
 
 - Fix DM thin-pool's metadata to use proper btree root (from previous
   transaction) if metadata commit failed.
 
 - Add 'waitfor' module param to DM module (dm_mod) to allow dm-init to
   wait for the specified device before continuing with its DM target
   initialization.
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Merge tag 'for-6.2/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix use-after-free races due to missing resource cleanup during DM
   target destruction in DM targets: thin-pool, cache, integrity and
   clone.

 - Fix ABBA deadlocks in DM thin-pool and cache targets due to their use
   of a bufio client (that has a shrinker whose locking can cause the
   incorrect locking order).

 - Fix DM cache target to set its needs_check flag after first aborting
   the metadata (whereby using reset persistent-data objects to update
   the superblock with, otherwise the superblock update could be dropped
   due to aborting metadata). This was found with code-inspection when
   comparing with the equivalent in DM thinp code.

 - Fix DM thin-pool's presume to continue resuming the device even if
   the pool in is fail mode -- otherwise bios may never be failed up the
   IO stack (which will prevent resetting the thin-pool target via table
   reload)

 - Fix DM thin-pool's metadata to use proper btree root (from previous
   transaction) if metadata commit failed.

 - Add 'waitfor' module param to DM module (dm_mod) to allow dm-init to
   wait for the specified device before continuing with its DM target
   initialization.

* tag 'for-6.2/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm thin: Use last transaction's pmd->root when commit failed
  dm init: add dm-mod.waitfor to wait for asynchronously probed block devices
  dm ioctl: fix a couple ioctl codes
  dm ioctl: a small code cleanup in list_version_get_info
  dm thin: resume even if in FAIL mode
  dm cache: set needs_check flag after aborting metadata
  dm cache: Fix ABBA deadlock between shrink_slab and dm_cache_metadata_abort
  dm thin: Fix ABBA deadlock between shrink_slab and dm_pool_abort_metadata
  dm integrity: Fix UAF in dm_integrity_dtr()
  dm cache: Fix UAF in destroy()
  dm clone: Fix UAF in clone_dtr()
  dm thin: Fix UAF in run_timer_softirq()
2022-12-13 10:58:09 -08:00
Christoph Hellwig
c34b7ac650 block: remove bio_set_op_attrs
This macro is obsolete, so replace the last few uses with open coded
bi_opf assignments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Coly Li <colyli@suse.de <mailto:colyli@suse.de>>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221206144057.720846-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-12-07 09:43:12 -07:00
Luo Meng
19eb1650af dm thin: resume even if in FAIL mode
If a thinpool set fail_io while suspending, resume will fail with:
 device-mapper: resume ioctl on vg-thinpool  failed: Invalid argument

The thin-pool also can't be removed if an in-flight bio is in the
deferred list.

This can be easily reproduced using:

  echo "offline" > /sys/block/sda/device/state
  dd if=/dev/zero of=/dev/mapper/thin bs=4K count=1
  dmsetup suspend /dev/mapper/pool
  mkfs.ext4 /dev/mapper/thin
  dmsetup resume /dev/mapper/pool

The root cause is maybe_resize_data_dev() will check fail_io and return
error before called dm_resume.

Fix this by adding FAIL mode check at the end of pool_preresume().

Cc: stable@vger.kernel.org
Fixes: da105ed5fd ("dm thin metadata: introduce dm_pool_abort_metadata")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-12-01 11:43:41 -05:00
Luo Meng
88430ebcbc dm thin: Fix UAF in run_timer_softirq()
When dm_resume() and dm_destroy() are concurrent, it will
lead to UAF, as follows:

 BUG: KASAN: use-after-free in __run_timers+0x173/0x710
 Write of size 8 at addr ffff88816d9490f0 by task swapper/0/0
<snip>
 Call Trace:
  <IRQ>
  dump_stack_lvl+0x73/0x9f
  print_report.cold+0x132/0xaa2
  _raw_spin_lock_irqsave+0xcd/0x160
  __run_timers+0x173/0x710
  kasan_report+0xad/0x110
  __run_timers+0x173/0x710
  __asan_store8+0x9c/0x140
  __run_timers+0x173/0x710
  call_timer_fn+0x310/0x310
  pvclock_clocksource_read+0xfa/0x250
  kvm_clock_read+0x2c/0x70
  kvm_clock_get_cycles+0xd/0x20
  ktime_get+0x5c/0x110
  lapic_next_event+0x38/0x50
  clockevents_program_event+0xf1/0x1e0
  run_timer_softirq+0x49/0x90
  __do_softirq+0x16e/0x62c
  __irq_exit_rcu+0x1fa/0x270
  irq_exit_rcu+0x12/0x20
  sysvec_apic_timer_interrupt+0x8e/0xc0

One of the concurrency UAF can be shown as below:

        use                                  free
do_resume                           |
  __find_device_hash_cell           |
    dm_get                          |
      atomic_inc(&md->holders)      |
                                    | dm_destroy
                                    |   __dm_destroy
                                    |     if (!dm_suspended_md(md))
                                    |     atomic_read(&md->holders)
                                    |     msleep(1)
  dm_resume                         |
    __dm_resume                     |
      dm_table_resume_targets       |
        pool_resume                 |
          do_waker  #add delay work |
  dm_put                            |
    atomic_dec(&md->holders)        |
                                    |     dm_table_destroy
                                    |       pool_dtr
                                    |         __pool_dec
                                    |           __pool_destroy
                                    |             destroy_workqueue
                                    |             kfree(pool) # free pool
        time out
__do_softirq
  run_timer_softirq # pool has already been freed

This can be easily reproduced using:
  1. create thin-pool
  2. dmsetup suspend pool
  3. dmsetup resume pool
  4. dmsetup remove_all # Concurrent with 3

The root cause of this UAF bug is that dm_resume() adds timer after
dm_destroy() skips cancelling the timer because of suspend status.
After timeout, it will call run_timer_softirq(), however pool has
already been freed. The concurrency UAF bug will happen.

Therefore, cancelling timer again in __pool_destroy().

Cc: stable@vger.kernel.org
Fixes: 991d9fa02d ("dm: add thin provisioning target")
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-11-30 13:29:34 -05:00
Luo Meng
3534e5a5ed dm thin: fix use-after-free crash in dm_sm_register_threshold_callback
Fault inject on pool metadata device reports:
  BUG: KASAN: use-after-free in dm_pool_register_metadata_threshold+0x40/0x80
  Read of size 8 at addr ffff8881b9d50068 by task dmsetup/950

  CPU: 7 PID: 950 Comm: dmsetup Tainted: G        W         5.19.0-rc6 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x34/0x44
   print_address_description.constprop.0.cold+0xeb/0x3f4
   kasan_report.cold+0xe6/0x147
   dm_pool_register_metadata_threshold+0x40/0x80
   pool_ctr+0xa0a/0x1150
   dm_table_add_target+0x2c8/0x640
   table_load+0x1fd/0x430
   ctl_ioctl+0x2c4/0x5a0
   dm_ctl_ioctl+0xa/0x10
   __x64_sys_ioctl+0xb3/0xd0
   do_syscall_64+0x35/0x80
   entry_SYSCALL_64_after_hwframe+0x46/0xb0

This can be easily reproduced using:
  echo offline > /sys/block/sda/device/state
  dd if=/dev/zero of=/dev/mapper/thin bs=4k count=10
  dmsetup load pool --table "0 20971520 thin-pool /dev/sda /dev/sdb 128 0 0"

If a metadata commit fails, the transaction will be aborted and the
metadata space maps will be destroyed. If a DM table reload then
happens for this failed thin-pool, a use-after-free will occur in
dm_sm_register_threshold_callback (called from
dm_pool_register_metadata_threshold).

Fix this by in dm_pool_register_metadata_threshold() by returning the
-EINVAL error if the thin-pool is in fail mode. Also fail pool_ctr()
with a new error message: "Error registering metadata threshold".

Fixes: ac8c3f3df6 ("dm thin: generate event when metadata threshold passed")
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-15 18:09:14 -04:00
Christoph Hellwig
44abff2c0b block: decouple REQ_OP_SECURE_ERASE from REQ_OP_DISCARD
Secure erase is a very different operation from discard in that it is
a data integrity operation vs hint.  Fully split the limits and helper
infrastructure to make the separation more clear.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> [nifs2]
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org> [f2fs]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Chao Yu <chao@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-27-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-17 19:49:59 -06:00
Christoph Hellwig
70200574cc block: remove QUEUE_FLAG_DISCARD
Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-17 19:49:59 -06:00
Mike Snitzer
b7f8dff098 dm: simplify dm_sumbit_bio_remap interface
Remove the from_wq argument from dm_sumbit_bio_remap(). Eliminates the
need for dm_sumbit_bio_remap() callers to know whether they are
calling for a workqueue or from the original dm_submit_bio().

Add map_task to dm_io struct, record the map_task in alloc_io and
clear it after all target ->map() calls have completed. Update
dm_sumbit_bio_remap to check if 'current' matches io->map_task rather
than rely on passed 'from_rq' argument.

This change really simplifies the chore of porting each DM target to
using dm_sumbit_bio_remap() because there is no longer the risk of
programming error by not completely knowing all the different contexts
a particular method that calls dm_sumbit_bio_remap() might be used in.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2022-03-10 13:44:56 -05:00
Mike Snitzer
a92512819b dm thin: use dm_submit_bio_remap
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2022-03-10 13:44:55 -05:00
Christoph Hellwig
385411ffba dm: stop using bdevname
Just use the %pg format specifier instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2022-03-02 12:15:54 -05:00
Wang Qing
8ca8b1e147 dm thin: use time_is_before_jiffies instead of open coding it
Use time_is_before_jiffies() to improve code readability.

Signed-off-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2022-02-22 11:30:50 -05:00
Christoph Hellwig
07888c665b block: pass a block_device and opf to bio_alloc
Pass the block_device and operation that we plan to use this bio for to
bio_alloc to optimize the assignment.  NULL/0 can be passed, both for the
passthrough case on a raw request_queue and to temporarily avoid
refactoring some nasty code.

Also move the gfp_mask argument after the nr_vecs argument for a much
more logical calling convention matching what most of the kernel does.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220124091107.642561-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Christoph Hellwig
28d7d128aa dm-thin: use blkdev_issue_flush instead of open coding it
Use blkdev_issue_flush, which uses an on-stack bio instead of an
opencoded version with a bio embedded into struct pool.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124091107.642561-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Christoph Hellwig
53db984e00 dm: bio_alloc can't fail if it is allowed to sleep
Remove handling of NULL returns from sleeping bio_alloc calls given that
those can't fail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124091107.642561-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Christoph Hellwig
6dcbb52cdd dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them
Use the proper helpers to read the block device size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20211018101130.1838532-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:43:22 -06:00
Tushar Sugandhi
8ec456629d dm: update target status functions to support IMA measurement
For device mapper targets to take advantage of IMA's measurement
capabilities, the status functions for the individual targets need to be
updated to handle the status_type_t case for value STATUSTYPE_IMA.

Update status functions for the following target types, to log their
respective attributes to be measured using IMA.
 01. cache
 02. crypt
 03. integrity
 04. linear
 05. mirror
 06. multipath
 07. raid
 08. snapshot
 09. striped
 10. verity

For rest of the targets, handle the STATUSTYPE_IMA case by setting the
measurement buffer to NULL.

For IMA to measure the data on a given system, the IMA policy on the
system needs to be updated to have the following line, and the system
needs to be restarted for the measurements to take effect.

/etc/ima/ima-policy
 measure func=CRITICAL_DATA label=device-mapper template=ima-buf

The measurements will be reflected in the IMA logs, which are located at:

/sys/kernel/security/integrity/ima/ascii_runtime_measurements
/sys/kernel/security/integrity/ima/binary_runtime_measurements

These IMA logs can later be consumed by various attestation clients
running on the system, and send them to external services for attesting
the system.

The DM target data measured by IMA subsystem can alternatively
be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
DM_TABLE_STATUS_CMD.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-10 13:34:23 -04:00
Xu Wang
695902bb2e dm thin: remove needless request_queue NULL pointer check
Since commit ff9ea32381 ("block, bdi: an active gendisk always has a
request_queue associated with it") the request_queue pointer returned
from bdev_get_queue() shall never be NULL.

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-03-26 14:53:42 -04:00
Christoph Hellwig
21cf866145 writeback: remove bdi->congested_fn
Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures.  And
pktdvd is a deprecated driver that isn't useful in stack setup
either.  So remove the dead congested_fn stacking infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-08 17:20:46 -06:00
Christoph Hellwig
ed00aabd5e block: rename generic_make_request to submit_bio_noacct
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01 07:27:24 -06:00
Mikulas Patocka
f06c03d1de dm thin: change data device's flush_bio to be member of struct pool
With commit fe64369163c5 ("dm thin: don't allow changing data device
during thin-pool load") it is now possible to re-parent the data
device's flush_bio from the pool_c to pool structure.  Doing so offers
improved lifetime guarantees for the flush_bio so that the call to
dm_pool_register_pre_commit_callback can now be done safely from
pool_ctr().

Depends-on: fe64369163c5 ("dm thin: don't allow changing data device during thin-pool load")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:23:13 -05:00
Mikulas Patocka
873937e75f dm thin: don't allow changing data device during thin-pool reload
The existing code allows changing the data device when the thin-pool
target is reloaded.

This capability is not required and only complicates device lifetime
guarantees. This can cause crashes like the one reported here:
	https://bugzilla.redhat.com/show_bug.cgi?id=1788596
where the kernel tries to issue a flush bio located in a structure that
was already freed.

Take the first step to simplifying the thin-pool's data device lifetime
by disallowing changing it. Like the thin-pool's metadata device, the
data device is now set in pool_create() and it cannot be changed for a
given thin-pool.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:51 -05:00
Mike Snitzer
a4a8d28658 dm thin: fix use-after-free in metadata_pre_commit_callback
dm-thin uses struct pool to hold the state of the pool. There may be
multiple pool_c's pointing to a given pool, each pool_c represents a
loaded target. pool_c's may be created and destroyed arbitrarily and the
pool contains a reference count of pool_c's pointing to it.

Since commit 694cfe7f31 ("dm thin: Flush data device before
committing metadata") a pointer to pool_c is passed to
dm_pool_register_pre_commit_callback and this function stores it in
pmd->pre_commit_context. If this pool_c is freed, but pool is not
(because there is another pool_c referencing it), we end up in a
situation where pmd->pre_commit_context structure points to freed
pool_c. It causes a crash in metadata_pre_commit_callback.

Fix this by moving the dm_pool_register_pre_commit_callback() from
pool_ctr() to pool_preresume(). This way the in-core thin-pool metadata
is only ever armed with callback data whose lifetime matches the
active thin-pool target.

In should be noted that this fix preserves the ability to load a
thin-pool table that uses a different data block device (that contains
the same data) -- though it is unclear if that capability is still
useful and/or needed.

Fixes: 694cfe7f31 ("dm thin: Flush data device before committing metadata")
Cc: stable@vger.kernel.org
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-14 20:22:50 -05:00
Nikos Tsironis
694cfe7f31 dm thin: Flush data device before committing metadata
The thin provisioning target maintains per thin device mappings that map
virtual blocks to data blocks in the data device.

When we write to a shared block, in case of internal snapshots, or
provision a new block, in case of external snapshots, we copy the shared
block to a new data block (COW), update the mapping for the relevant
virtual block and then issue the write to the new data block.

Suppose the data device has a volatile write-back cache and the
following sequence of events occur:

1. We write to a shared block
2. A new data block is allocated
3. We copy the shared block to the new data block using kcopyd (COW)
4. We insert the new mapping for the virtual block in the btree for that
   thin device.
5. The commit timeout expires and we commit the metadata, that now
   includes the new mapping from step (4).
6. The system crashes and the data device's cache has not been flushed,
   meaning that the COWed data are lost.

The next time we read that virtual block of the thin device we read it
from the data block allocated in step (2), since the metadata have been
successfully committed. The data are lost due to the crash, so we read
garbage instead of the old, shared data.

This has the following implications:

1. In case of writes to shared blocks, with size smaller than the pool's
   block size (which means we first copy the whole block and then issue
   the smaller write), we corrupt data that the user never touched.

2. In case of writes to shared blocks, with size equal to the device's
   logical block size, we fail to provide atomic sector writes. When the
   system recovers the user will read garbage from that sector instead
   of the old data or the new data.

3. Even for writes to shared blocks, with size equal to the pool's block
   size (overwrites), after the system recovers, the written sectors
   will contain garbage instead of a random mix of sectors containing
   either old data or new data, thus we fail again to provide atomic
   sectors writes.

4. Even when the user flushes the thin device, because we first commit
   the metadata and then pass down the flush, the same risk for
   corruption exists (if the system crashes after the metadata have been
   committed but before the flush is passed down to the data device.)

The only case which is unaffected is that of writes with size equal to
the pool's block size and with the FUA flag set. But, because FUA writes
trigger metadata commits, this case can trigger the corruption
indirectly.

Moreover, apart from internal and external snapshots, the same issue
exists for newly provisioned blocks, when block zeroing is enabled.
After the system recovers the provisioned blocks might contain garbage
instead of zeroes.

To solve this and avoid the potential data corruption we flush the
pool's data device **before** committing its metadata.

This ensures that the data blocks of any newly inserted mappings are
properly written to non-volatile storage and won't be lost in case of a
crash.

Cc: stable@vger.kernel.org
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-06 11:46:16 -05:00
Jeffle Xu
d256d79627 dm thin: wakeup worker only when deferred bios exist
Single thread fio test (read, bs=4k, ioengine=libaio, iodepth=128,
numjobs=1) over dm-thin device has poor performance versus bare nvme
device.

Further investigation with perf indicates that queue_work_on() consumes
over 20% CPU time when doing IO over dm-thin device. The call stack is
as follows.

- 40.57% thin_map
    + 22.07% queue_work_on
    + 9.95% dm_thin_find_block
    + 2.80% cell_defer_no_holder
      1.91% inc_all_io_entry.isra.33.part.34
    + 1.78% bio_detain.isra.35

In cell_defer_no_holder(), wakeup_worker() is always called, no matter
whether the tc->deferred_bio_list list is empty or not. In single thread
IO model, this list is most likely empty. So skip waking up worker thread
if tc->deferred_bio_list list is empty.

Single thread IO performance improves from 448 MiB/s to 646 MiB/s (+44%)
once the needless wake_worker() calls are properly skipped.

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-18 10:03:12 -05:00