Commit Graph

49 Commits

Author SHA1 Message Date
Mikulas Patocka 2ee73ef60d dm writecache: count number of blocks discarded, not number of discard bios
Change dm-writecache, so that it counts the number of blocks discarded
instead of the number of discard bios. Make it consistent with the
read and write statistics counters that were changed to count the
number of blocks instead of bios.

Fixes: e3a35d0340 ("dm writecache: add event counters")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-14 15:54:46 -04:00
Mikulas Patocka b2676e1482 dm writecache: count number of blocks written, not number of write bios
Change dm-writecache, so that it counts the number of blocks written
instead of the number of write bios. Bios can be split and requeued
using the dm_accept_partial_bio function, so counting bios caused
inaccurate results.

Fixes: e3a35d0340 ("dm writecache: add event counters")
Reported-by: Yu Kuai <yukuai1@huaweicloud.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-14 15:53:25 -04:00
Mikulas Patocka 2c6e755b49 dm writecache: count number of blocks read, not number of read bios
Change dm-writecache, so that it counts the number of blocks read
instead of the number of read bios. Bios can be split and requeued
using the dm_accept_partial_bio function, so counting bios caused
inaccurate results.

Fixes: e3a35d0340 ("dm writecache: add event counters")
Reported-by: Yu Kuai <yukuai1@huaweicloud.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-14 15:52:32 -04:00
Bagas Sanjaya 11093e6f0d Documentation: dm writecache: Render status list as list
The status list isn't rendered as list, but rather as normal paragraph,
because there is missing blank line between "Status:" line and the list.

Fix the issue by adding the blank line separator.

Fixes: 48debafe4f ("dm: add writecache target")
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-07 14:40:32 -04:00
Mauro Carvalho Chehab 8b301af4c6 Documentation: dm writecache: add blank line before optional parameters
Otherwise this warning occurs:
  Documentation/admin-guide/device-mapper/writecache.rst:23: WARNING: Unexpected indentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
2022-07-07 14:37:58 -04:00
Tushar Sugandhi 17bfa96851 dm ima: update dm documentation for ima measurement support
The ima documentation for measuring DM targets (dm-ima.rst) is
missing the attribute information for the targets - 'cache', 'integrity',
'multipath', and 'snapshot'.  It is also missing the grammar for
various DM events and targets, which can help the attestation servers
to determine what data to expect for a given DM device.  Further,
the documentation needs to be updated to incorporate code changes
made to DM ima events and targets as part of this patch series.  For
instance, prefixing the event names with "dm_", adding the DM version to
events, prefixing the table hashes in the ima log with the
hash algorithm etc.  There are warnings reported by 'make htmldocs' on
dm-ima.rst, which need to be fixed.  And lastly, the expected behavior
needs to be documented when the configuration CONFIG_IMA_DISABLE_HTABLE
is disabled.

Update the documentation to add examples for 'cache', 'integrity',
'multipath', and 'snapshot' targets.  Add the grammar for
various DM events and targets in Backus Naur form,
so that the attestation servers can interpret and act on the ima
measurements for DM target.  Fix htmldocs warnings in dm-ima.rst.  Update
the documentation to be consistent with the code changes that are part of
this patch series.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-20 16:07:37 -04:00
Tushar Sugandhi 00d43995f0 dm: add documentation for IMA measurement support
To interpret various DM target measurement data in IMA logs,
a separate documentation page is needed under
Documentation/admin-guide/device-mapper.

Add documentation to help system administrators and attestation
client/server component owners to interpret the measurement
data generated by various DM targets, on various device/table state
changes.

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
Mikulas Patocka e3a35d0340 dm writecache: add event counters
Add 10 counters for various events (hit, miss, etc) and export them in
the status line (accessed from userspace with "dmsetup status"). Also
add a message "clear_stats" that resets these counters.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-08-10 13:27:49 -04:00
Mikulas Patocka 5c0de3d72f dm writecache: make writeback pause configurable
Commit 95b88f4d71 ("dm writecache: pause
writeback if cache full and origin being written directly") introduced a
code that pauses cache flushing if we are issuing writes directly to the
origin.

Improve that initial commit by making the timeout code configurable
(via the option "pause_writeback"). Also change the default from 1s to
3s because it performed better.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-28 16:30:13 -04:00
Mikulas Patocka 611c3e168b dm writecache: add optional "metadata_only" parameter
Add a "metadata_only" parameter that when present: only metadata is
promoted to the cache. This option improves performance for heavier
REQ_META workloads (e.g. device-mapper-test-suite's "git clone and
checkout" benchmark improves from 341s to 312s).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25 15:25:21 -04:00
Mike Snitzer cd039afa0a dm writecache: add "cleaner" and "max_age" to Documentation
Backfill missing Documentation.

Fixes: 93de44eb3f ("dm writecache: implement the "cleaner" policy")
Fixes: 3923d4854e ("dm writecache: implement gradual cleanup")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-25 15:25:19 -04:00
Linus Torvalds 325b764089 - Fix DM integrity's HMAC support to provide enhanced security of
internal_hash and journal_mac capabilities.
 
 - Various DM writecache fixes to address performance, fix table output
   to match what was provided at table creation, fix writing beyond end
   of device when shrinking underlying data device, and a couple other
   small cleanups.
 
 - Add DM crypt support for using trusted keys.
 
 - Fix deadlock when swapping to DM crypt device by throttling number
   of in-flight REQ_SWAP bios. Implemented in DM core so that other
   bio-based targets can opt-in by setting ti->limit_swap_bios.
 
 - Fix various inverted logic bugs in the .iterate_devices callout
   functions that are used to assess if specific feature or capability
   is supported across all devices being combined/stacked by DM.
 
 - Fix DM era target bugs that exposed users to lost writes or memory
   leaks.
 
 - Add DM core support for passing through inline crypto support of
   underlying devices. Includes block/keyslot-manager changes that
   enable extending this support to DM.
 
 - Various small fixes and cleanups (spelling fixes, front padding
   calculation cleanup, cleanup conditional zoned support in targets,
   etc).
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Merge tag 'for-5.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Fix DM integrity's HMAC support to provide enhanced security of
   internal_hash and journal_mac capabilities.

 - Various DM writecache fixes to address performance, fix table output
   to match what was provided at table creation, fix writing beyond end
   of device when shrinking underlying data device, and a couple other
   small cleanups.

 - Add DM crypt support for using trusted keys.

 - Fix deadlock when swapping to DM crypt device by throttling number of
   in-flight REQ_SWAP bios. Implemented in DM core so that other
   bio-based targets can opt-in by setting ti->limit_swap_bios.

 - Fix various inverted logic bugs in the .iterate_devices callout
   functions that are used to assess if specific feature or capability
   is supported across all devices being combined/stacked by DM.

 - Fix DM era target bugs that exposed users to lost writes or memory
   leaks.

 - Add DM core support for passing through inline crypto support of
   underlying devices. Includes block/keyslot-manager changes that
   enable extending this support to DM.

 - Various small fixes and cleanups (spelling fixes, front padding
   calculation cleanup, cleanup conditional zoned support in targets,
   etc).

* tag 'for-5.12/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (31 commits)
  dm: fix deadlock when swapping to encrypted device
  dm: simplify target code conditional on CONFIG_BLK_DEV_ZONED
  dm: set DM_TARGET_PASSES_CRYPTO feature for some targets
  dm: support key eviction from keyslot managers of underlying devices
  dm: add support for passing through inline crypto support
  block/keyslot-manager: Introduce functions for device mapper support
  block/keyslot-manager: Introduce passthrough keyslot manager
  dm era: only resize metadata in preresume
  dm era: Use correct value size in equality function of writeset tree
  dm era: Fix bitset memory leaks
  dm era: Verify the data block size hasn't changed
  dm era: Reinitialize bitset cache before digesting a new writeset
  dm era: Update in-core bitset after committing the metadata
  dm era: Recover committed writeset after crash
  dm writecache: use bdev_nr_sectors() instead of open-coded equivalent
  dm writecache: fix writing beyond end of underlying device when shrinking
  dm table: remove needless request_queue NULL pointer checks
  dm table: fix zoned iterate_devices based device capability checks
  dm table: fix DAX iterate_devices based device capability checks
  dm table: fix iterate_devices based device capability checks
  ...
2021-02-22 10:22:54 -08:00
Linus Torvalds 31caf8b2a8 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "API:
   - Restrict crypto_cipher to internal API users only.

  Algorithms:
   - Add x86 aesni acceleration for cts.
   - Improve x86 aesni acceleration for xts.
   - Remove x86 acceleration of some uncommon algorithms.
   - Remove RIPE-MD, Tiger and Salsa20.
   - Remove tnepres.
   - Add ARM acceleration for BLAKE2s and BLAKE2b.

  Drivers:
   - Add Keem Bay OCS HCU driver.
   - Add Marvell OcteonTX2 CPT PF driver.
   - Remove PicoXcell driver.
   - Remove mediatek driver"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (154 commits)
  hwrng: timeriomem - Use device-managed registration API
  crypto: hisilicon/qm - fix printing format issue
  crypto: hisilicon/qm - do not reset hardware when CE happens
  crypto: hisilicon/qm - update irqflag
  crypto: hisilicon/qm - fix the value of 'QM_SQC_VFT_BASE_MASK_V2'
  crypto: hisilicon/qm - fix request missing error
  crypto: hisilicon/qm - removing driver after reset
  crypto: octeontx2 - fix -Wpointer-bool-conversion warning
  crypto: hisilicon/hpre - enable Elliptic curve cryptography
  crypto: hisilicon - PASID fixed on Kunpeng 930
  crypto: hisilicon/qm - fix use of 'dma_map_single'
  crypto: hisilicon/hpre - tiny fix
  crypto: hisilicon/hpre - adapt the number of clusters
  crypto: cpt - remove casting dma_alloc_coherent
  crypto: keembay-ocs-aes - Fix 'q' assignment during CCM B0 generation
  crypto: xor - Fix typo of optimization
  hwrng: optee - Use device-managed registration API
  crypto: arm64/crc-t10dif - move NEON yield to C code
  crypto: arm64/aes-ce-mac - simplify NEON yield
  crypto: arm64/aes-neonbs - remove NEON yield calls
  ...
2021-02-21 17:23:56 -08:00
Ahmad Fatoum 363880c4eb dm crypt: support using trusted keys
Commit 27f5411a71 ("dm crypt: support using encrypted keys") extended
dm-crypt to allow use of "encrypted" keys along with "user" and "logon".

Along the same lines, teach dm-crypt to support "trusted" keys as well.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-02-03 10:13:00 -05:00
Mikulas Patocka 09d85f8d89 dm integrity: introduce the "fix_hmac" argument
The "fix_hmac" argument improves security of internal_hash and
journal_mac:
- the section number is mixed to the mac, so that an attacker can't
  copy sectors from one journal section to another journal section
- the superblock is protected by journal_mac
- a 16-byte salt stored in the superblock is mixed to the mac, so
  that the attacker can't detect that two disks have the same hmac
  key and also to disallow the attacker to move sectors from one
  disk to another

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Daniel Glockner <dg@emlix.com>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> # ReST fix
Tested-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-02-03 10:10:05 -05:00
Ard Biesheuvel 663f63ee6d crypto: salsa20 - remove Salsa20 stream cipher algorithm
Salsa20 is not used anywhere in the kernel, is not suitable for disk
encryption, and widely considered to have been superseded by ChaCha20.
So let's remove it.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by:  Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-01-29 16:07:04 +11:00
Mikulas Patocka 5c02406428 dm integrity: conditionally disable "recalculate" feature
Otherwise a malicious user could (ab)use the "recalculate" feature
that makes dm-integrity calculate the checksums in the background
while the device is already usable. When the system restarts before all
checksums have been calculated, the calculation continues where it was
interrupted even if the recalculate feature is not requested the next
time the dm device is set up.

Disable recalculating if we use internal_hash or journal_hash with a
key (e.g. HMAC) and we don't have the "legacy_recalculate" flag.

This may break activation of a volume, created by an older kernel,
that is not yet fully recalculated -- if this happens, the user should
add the "legacy_recalculate" flag to constructor parameters.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Daniel Glockner <dg@emlix.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-01-21 15:05:21 -05:00
Linus Torvalds d8355e740f - Add DM verity support for signature verification with 2nd keyring.
- Fix DM verity to skip verity work if IO completes with error while
   system is shutting down.
 
 - Add new DM multipath "IO affinity" path selector that maps IO
   destined to a given path to a specific CPU based on user provided
   mapping.
 
 - Rename DM multipath path selector source files to have "dm-ps"
   prefix.
 
 - Add REQ_NOWAIT support to some other simple DM targets that don't
   block in more elaborate ways waiting for IO.
 
 - Export DM crypt's kcryptd workqueue via sysfs (WQ_SYSFS).
 
 - Fix error return code in DM's target_message() if empty message is
   received.
 
 - A handful of other small cleanups.
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Merge tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Add DM verity support for signature verification with 2nd keyring

 - Fix DM verity to skip verity work if IO completes with error while
   system is shutting down

 - Add new DM multipath "IO affinity" path selector that maps IO
   destined to a given path to a specific CPU based on user provided
   mapping

 - Rename DM multipath path selector source files to have "dm-ps" prefix

 - Add REQ_NOWAIT support to some other simple DM targets that don't
   block in more elaborate ways waiting for IO

 - Export DM crypt's kcryptd workqueue via sysfs (WQ_SYSFS)

 - Fix error return code in DM's target_message() if empty message is
   received

 - A handful of other small cleanups

* tag 'for-5.11/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm cache: simplify the return expression of load_mapping()
  dm ebs: avoid double unlikely() notation when using IS_ERR()
  dm verity: skip verity work if I/O error when system is shutting down
  dm crypt: export sysfs of kcryptd workqueue
  dm ioctl: fix error return code in target_message
  dm crypt: Constify static crypt_iv_operations
  dm: add support for REQ_NOWAIT to various targets
  dm: rename multipath path selector source files to have "dm-ps" prefix
  dm mpath: add IO affinity path selector
  dm verity: Add support for signature verification with 2nd keyring
  dm: remove unnecessary current->bio_list check when submitting split bio
2020-12-22 13:27:21 -08:00
Andrew Klychkov 751d5b2741 Documentation: fix multiple typos found in the admin-guide subdirectory
Fix thirty five typos in dm-integrity.rst, dm-raid.rst, dm-zoned.rst,
verity.rst, writecache.rst, tsx_async_abort.rst, md.rst, bttv.rst,
dvb_references.rst, frontend-cardlist.rst, gspca-cardlist.rst, ipu3.rst,
remote-controller.rst, mm/index.rst, numaperf.rst, userfaultfd.rst,
module-signing.rst, imx-ddr.rst, intel-speed-select.rst,
intel_pstate.rst, ramoops.rst, abi.rst, kernel.rst, vm.rst

Signed-off-by: Andrew Klychkov <andrew.a.klychkov@gmail.com>
Link: https://lore.kernel.org/r/20201204072848.GA49895@spblnx124.lan
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-08 10:27:56 -07:00
Andrew Klychkov b2105aa2c6 Documentation: fix typos found in admin-guide subdirectory
Fixed twelve typos in cppc_sysfs.rst, binderfs.rst, paride.rst,
zram.rst, bug-hunting.rst, introduction.rst, usage.rst, dm-crypt.rst

Signed-off-by: Andrew Klychkov <andrew.a.klychkov@gmail.com>
Reviewed-by: Jonathan Corbet <corbet@lwn.net>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20201204070235.GA48631@spblnx124.lan
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-08 10:25:42 -07:00
Mickaël Salaün 4da8f8c8a1 dm verity: Add support for signature verification with 2nd keyring
Add a new configuration DM_VERITY_VERIFY_ROOTHASH_SIG_SECONDARY_KEYRING
to enable dm-verity signatures to be verified against the secondary
trusted keyring.  Instead of relying on the builtin trusted keyring
(with hard-coded certificates), the second trusted keyring can include
certificate authorities from the builtin trusted keyring and child
certificates loaded at run time.  Using the secondary trusted keyring
enables to use dm-verity disks (e.g. loop devices) signed by keys which
did not exist at kernel build time, leveraging the certificate chain of
trust model.  In practice, this makes it possible to update certificates
without kernel update and reboot, aligning with module and kernel
(kexec) signature verification which already use the secondary trusted
keyring.

Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-12-04 18:04:35 -05:00
Milan Broz 4c07ae0ad4 dm crypt: document encrypted keyring key option
Commit 27f5411a71 ("dm crypt: support using encrypted keys")
introduced support for encrypted keyring type.

Fix documentation in admin guide to mention this type.

Fixes: 27f5411a71 ("dm crypt: support using encrypted keys")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-09-22 13:25:58 -04:00
Milan Broz 4a5caa4af0 dm crypt: document new no_workqueue flags
Commit 39d42fa96b ("dm crypt: add flags to optionally bypass kcryptd
workqueues") introduced new dm-crypt 'no_read_workqueue' and
'no_write_workqueue' flags.

Add documentation to admin guide for them.

Fixes: 39d42fa96b ("dm crypt: add flags to optionally bypass kcryptd workqueues")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-09-22 13:24:46 -04:00
Linus Torvalds 2f12d44085 - DM multipath locking fixes around m->flags tests and improvements to
bio-based code so that it follows patterns established by
   request-based code.
 
 - Request-based DM core improvement to eliminate unnecessary call to
   blk_mq_queue_stopped().
 
 - Add "panic_on_corruption" error handling mode to DM verity target.
 
 - DM bufio fix to to perform buffer cleanup from a workqueue rather
   than wait for IO in reclaim context from shrinker.
 
 - DM crypt improvement to optionally avoid async processing via
   workqueues for reads and/or writes -- via "no_read_workqueue" and
   "no_write_workqueue" features.  This more direct IO processing
   improves latency and throughput with faster storage.  Avoiding
   workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is
   a requirement for adding zoned block device support to DM crypt.
 
 - Add zoned block device support to DM crypt.  Makes use of
   DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature
   (DM_CRYPT_WRITE_INLINE) that allows write completion to wait for
   encryption to complete.  This allows write ordering to be preserved,
   which is needed for zoned block devices.
 
 - Fix DM ebs target's check for REQ_OP_FLUSH.
 
 - Fix DM core's report zones support to not report more zones than
   were requested.
 
 - A few small compiler warning fixes.
 
 - DM dust improvements to return output directly to the user rather
   than require they scrape the system log for output.
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Merge tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - DM multipath locking fixes around m->flags tests and improvements to
   bio-based code so that it follows patterns established by
   request-based code.

 - Request-based DM core improvement to eliminate unnecessary call to
   blk_mq_queue_stopped().

 - Add "panic_on_corruption" error handling mode to DM verity target.

 - DM bufio fix to to perform buffer cleanup from a workqueue rather
   than wait for IO in reclaim context from shrinker.

 - DM crypt improvement to optionally avoid async processing via
   workqueues for reads and/or writes -- via "no_read_workqueue" and
   "no_write_workqueue" features. This more direct IO processing
   improves latency and throughput with faster storage. Avoiding
   workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a
   requirement for adding zoned block device support to DM crypt.

 - Add zoned block device support to DM crypt. Makes use of
   DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature
   (DM_CRYPT_WRITE_INLINE) that allows write completion to wait for
   encryption to complete. This allows write ordering to be preserved,
   which is needed for zoned block devices.

 - Fix DM ebs target's check for REQ_OP_FLUSH.

 - Fix DM core's report zones support to not report more zones than were
   requested.

 - A few small compiler warning fixes.

 - DM dust improvements to return output directly to the user rather
   than require they scrape the system log for output.

* tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm: don't call report zones for more than the user requested
  dm ebs: Fix incorrect checking for REQ_OP_FLUSH
  dm init: Set file local variable static
  dm ioctl: Fix compilation warning
  dm raid: Remove empty if statement
  dm verity: Fix compilation warning
  dm crypt: Enable zoned block device support
  dm crypt: add flags to optionally bypass kcryptd workqueues
  dm bufio: do buffer cleanup from a workqueue
  dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue()
  dm dust: add interface to list all badblocks
  dm dust: report some message results directly back to user
  dm verity: add "panic_on_corruption" error handling mode
  dm mpath: use double checked locking in fast path
  dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl
  dm mpath: rework __map_bio()
  dm mpath: factor out multipath_queue_bio
  dm mpath: push locking down to must_push_back_rq()
  dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH
  dm mpath: changes from initial m->flags locking audit
2020-08-07 13:08:09 -07:00
Linus Torvalds 2324d50d05 It's been a busy cycle for documentation - hopefully the busiest for a
while to come.  Changes include:
 
  - Some new Chinese translations
 
  - Progress on the battle against double words words and non-HTTPS URLs
 
  - Some block-mq documentation
 
  - More RST conversions from Mauro.  At this point, that task is
    essentially complete, so we shouldn't see this kind of churn again for a
    while.  Unless we decide to switch to asciidoc or something...:)
 
  - Lots of typo fixes, warning fixes, and more.
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Merge tag 'docs-5.9' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's been a busy cycle for documentation - hopefully the busiest for a
  while to come. Changes include:

   - Some new Chinese translations

   - Progress on the battle against double words words and non-HTTPS
     URLs

   - Some block-mq documentation

   - More RST conversions from Mauro. At this point, that task is
     essentially complete, so we shouldn't see this kind of churn again
     for a while. Unless we decide to switch to asciidoc or
     something...:)

   - Lots of typo fixes, warning fixes, and more"

* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
  scripts/kernel-doc: optionally treat warnings as errors
  docs: ia64: correct typo
  mailmap: add entry for <alobakin@marvell.com>
  doc/zh_CN: add cpu-load Chinese version
  Documentation/admin-guide: tainted-kernels: fix spelling mistake
  MAINTAINERS: adjust kprobes.rst entry to new location
  devices.txt: document rfkill allocation
  PCI: correct flag name
  docs: filesystems: vfs: correct flag name
  docs: filesystems: vfs: correct sync_mode flag names
  docs: path-lookup: markup fixes for emphasis
  docs: path-lookup: more markup fixes
  docs: path-lookup: fix HTML entity mojibake
  CREDITS: Replace HTTP links with HTTPS ones
  docs: process: Add an example for creating a fixes tag
  doc/zh_CN: add Chinese translation prefer section
  doc/zh_CN: add clearing-warn-once Chinese version
  doc/zh_CN: add admin-guide index
  doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
  futex: MAINTAINERS: Re-add selftests directory
  ...
2020-08-04 22:47:54 -07:00
yangerkun 0c248ea27f dm dust: add interface to list all badblocks
This interface may help anyone who want to know all badblocks without
querying for each block.

[Bryan: DMEMIT message if no blocks are in the bad block list.]

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Bryan Gurney <bgurney@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-20 11:17:41 -04:00
yangerkun 4f7f590b15 dm dust: report some message results directly back to user
Some messages (queryblock, countbadblocks, removebadblock) are best
reported directly to user directly. Do so with DMEMIT.

[Bryan: maintain __func__ output in DMEMIT messages]

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Bryan Gurney <bgurney@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-20 11:17:34 -04:00
JeongHyeon Lee e1fef0b08e dm verity: add "panic_on_corruption" error handling mode
Samsung smart phones may need the ability to panic on corruption.  Not
all devices provide the bootloader support needed to use the existing
"restart_on_corruption" mode.  Additional details for why Samsung needs
this new mode can be found here:
https://www.redhat.com/archives/dm-devel/2020-June/msg00235.html

Signed-off-by: jhs2.lee <jhs2.lee@samsung.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-07-13 11:47:33 -04:00
Alexander A. Klimov 6f3bc22bf5 Replace HTTP links with HTTPS ones: LVM
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
          If both the HTTP and HTTPS versions
          return 200 OK and serve the same content:
            Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200627103138.71885-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-05 14:28:27 -06:00
Randy Dunlap 4e578ba60c Documentation/admin-guide: dm-integrity: drop doubled words
Drop the doubled words "on" and "the".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: dm-devel@redhat.com
Link: https://lore.kernel.org/r/20200704032020.21923-4-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-05 14:01:48 -06:00
Mauro Carvalho Chehab e0034433a7 docs: device-mapper: add dm-ebs.rst to an index file
Solves this Sphinx warning:
	Documentation/admin-guide/device-mapper/dm-ebs.rst: WARNING: document isn't included in any toctree

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-19 12:21:56 -04:00
Mikulas Patocka 40e9c5ac4e dm integrity: add status line documentation
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-06-05 14:59:40 -04:00
Hannes Reinecke bd5c40313a dm zoned: metadata version 2
Implement handling for metadata version 2. The new metadata adds a
label and UUID for the device mapper device, and additional UUID for
the underlying block devices.

It also allows for an additional regular drive to be used for
emulating random access zones. The emulated zones will be placed
logically in front of the zones from the zoned block device, causing
the superblocks and metadata to be stored on that device.

The first zone of the original zoned device will be used to hold
another, tertiary copy of the metadata; this copy carries a generation
number of 0 and is never updated; it's just used for identification.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-20 17:09:43 -04:00
Hannes Reinecke 90b39d58f3 dm zoned: add 'message' callback
Add callback for 'dmsetup message' to allow the reclaim process
to be triggered manually.
Eg.

	dmsetup message /dev/dm-X 0 message

will start the reclaim process even if the default threshold
of 50 percent of free random zones is not reached.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15 10:29:36 -04:00
Hannes Reinecke bc3d5717d2 dm zoned: add 'status' callback
Add callback to supply information for 'dmsetup status'
and 'dmsetup table'. The output for 'dmsetup status' is

0 <size> zoned <nr_zones> zones <nr_unmap_rnd>/<nr_rnd> random <nr_unmap_seq>/<nr_seq> sequential

where <nr_unmap_rnd> is the number of unmapped (ie free) random zones,
<nr_rnd> the total number of random zones, <nr_unmap_seq> the number
of unmapped sequential zones, and <nr_seq> the total number of
sequential zones.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15 10:29:36 -04:00
Heinz Mauelshagen d3c7b35c20 dm: add emulated block size target
This new target is similar to the linear target except that it emulates
a smaller logical block size on a device with a larger logical block
size.  Its main purpose is to emulate 512 byte sectors on 4K native
disks (i.e. 512e).

See Documentation/admin-guide/device-mapper/dm-ebs.rst for details.

Reviewed-by: Damien Le Moal <DamienLeMoal@wdc.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [Kconfig fixes]
Signed-off-by: Zheng Bin <zhengbin13@huawei.com> [static fixes]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-05-15 10:29:35 -04:00
Milan Broz 0a2bd55c19 dm integrity: document allow_discard option
Add decription of the allow_discard option added in commit
84597a44a9.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-04-14 13:54:07 -04:00
Heinz Mauelshagen 43f3952a51 dm raid: table line rebuild status fixes
raid_status() wasn't emitting rebuild flags on the table line properly
because the rdev number was not yet set properly; index raid component
devices array directly to solve.

Also fix wrong argument count on emitted table line caused by 1 too
many rebuild/write_mostly argument and consider any journal_(dev|mode)
pairs.

Link: https://bugzilla.redhat.com/1782045
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-01-07 11:43:37 -05:00
Linus Torvalds 15da849c91 - Fix DM multipath by restoring full path selector functionality for
bio-based configurations that don't haave a SCSI device handler.
 
 - Fix dm-btree removal to ensure non-root btree nodes have at least
   (max_entries / 3) entries.  This resolves userspace thin_check
   utility's report of "too few entries in btree_node".
 
 - Fix both the DM thin-provisioning and dm-clone targets to properly
   flush the data device prior to metadata commit.  This resolves the
   potential for inconsistency across a power loss event when the data
   device has a volatile writeback cache.
 
 - Small documentation fixes to dm-clone and dm-integrity.
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Merge tag 'for-5.5/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 multipath by restoring full path selector functionality for
   bio-based configurations that don't haave a SCSI device handler.

 - Fix dm-btree removal to ensure non-root btree nodes have at least
   (max_entries / 3) entries. This resolves userspace thin_check
   utility's report of "too few entries in btree_node".

 - Fix both the DM thin-provisioning and dm-clone targets to properly
   flush the data device prior to metadata commit. This resolves the
   potential for inconsistency across a power loss event when the data
   device has a volatile writeback cache.

 - Small documentation fixes to dm-clone and dm-integrity.

* tag 'for-5.5/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  docs: dm-integrity: remove reference to ARC4
  dm thin: Flush data device before committing metadata
  dm thin metadata: Add support for a pre-commit callback
  dm clone: Flush destination device before committing metadata
  dm clone metadata: Use a two phase commit
  dm clone metadata: Track exact changes per transaction
  dm btree: increase rebalance threshold in __rebalance2()
  dm: add dm-clone to the documentation index
  dm mpath: remove harmful bio-based optimization
2019-12-13 14:13:15 -08:00
Eric Biggers 7fc979f820 docs: dm-integrity: remove reference to ARC4
ARC4 is no longer considered secure, so it shouldn't be used, even as
just an example.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-12-10 10:02:43 -05:00
Linus Torvalds 937d6eefc7 Here's the main documentation changes for 5.5:
- Various kerneldoc script enhancements.
 
  - More RST conversions; those are slowing down as we run out of things to
    convert, but we're a ways from done still.
 
  - Dan's "maintainer profile entry" work landed at last.  Now we just need
    to get maintainers to fill in the profiles...
 
  - A reworking of the parallel build setup to work better with a variety of
    systems (and to not take over huge systems entirely in particular).
 
  - The MAINTAINERS file is now converted to RST during the build.
    Hopefully nobody ever tries to print this thing, or they will need to
    load a lot of paper.
 
  - A script and documentation making it easy for maintainers to add Link:
    tags at commit time.
 
 Also included is the removal of a bunch of spurious CR characters.
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Merge tag 'docs-5.5a' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "Here are the main documentation changes for 5.5:

   - Various kerneldoc script enhancements.

   - More RST conversions; those are slowing down as we run out of
     things to convert, but we're a ways from done still.

   - Dan's "maintainer profile entry" work landed at last. Now we just
     need to get maintainers to fill in the profiles...

   - A reworking of the parallel build setup to work better with a
     variety of systems (and to not take over huge systems entirely in
     particular).

   - The MAINTAINERS file is now converted to RST during the build.
     Hopefully nobody ever tries to print this thing, or they will need
     to load a lot of paper.

   - A script and documentation making it easy for maintainers to add
     Link: tags at commit time.

  Also included is the removal of a bunch of spurious CR characters"

* tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits)
  docs: remove a bunch of stray CRs
  docs: fix up the maintainer profile document
  libnvdimm, MAINTAINERS: Maintainer Entry Profile
  Maintainer Handbook: Maintainer Entry Profile
  MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile
  docs, parallelism: Rearrange how jobserver reservations are made
  docs, parallelism: Do not leak blocking mode to other readers
  docs, parallelism: Fix failure path and add comment
  Documentation: Remove bootmem_debug from kernel-parameters.txt
  Documentation: security: core.rst: fix warnings
  Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning
  Documentation/translation: Use Korean for Korean translation title
  docs/memory-barriers.txt: Remove remaining references to mmiowb()
  docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread
  docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section
  Documentation/kokr: Kill all references to mmiowb()
  docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section
  docs: Add initial documentation for devfreq
  Documentation: Document how to get links with git am
  docs: Add request_irq() documentation
  ...
2019-12-02 11:51:02 -08:00
Diego Calleja 484e0d2b11 dm: add dm-clone to the documentation index
Fixes: 7431b7835f ("dm: add clone target")
Signed-off-by: Diego Calleja <diegocg@gmail.com>
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-26 10:33:50 -05:00
Mikulas Patocka d537858ac8 dm integrity: fix excessive alignment of metadata runs
Metadata runs are supposed to be aligned on 4k boundary (so that they work
efficiently with disks with 4k sectors). However, there was a programming
bug that makes them aligned on 128k boundary instead. The unused space is
wasted.

Fix this bug by providing a proper 4k alignment. In order to keep
existing volumes working, we introduce a new flag SB_FLAG_FIXED_PADDING
- when the flag is clear, we calculate the padding the old way. In order
to make sure that the old version cannot mount the volume created by the
new version, we increase superblock version to 4.

Also in order to not break with old integritysetup, we fix alignment
only if the parameter "fix_padding" is present when formatting the
device.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-15 14:49:16 -05:00
Heinz Mauelshagen 99273d9e6e dm raid: to ensure resynchronization, perform raid set grow in preresume
This fixes a flaw causing raid set extensions not to be synchronized
in case the MD bitmap resize required additional pages to be allocated.

Also share resize code in the raid constructor between
new size changes and those occuring during recovery.

Bump the target version to define the change and document
it in Documentation/admin-guide/device-mapper/dm-raid.rst.

Reported-by: Steve D <steved424@gmail.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-11-05 14:02:26 -05:00
Bryan Gurney 0a6f33dba4 dm dust: convert documentation to ReST
Convert the dm-dust documentation to ReST formatting, using literal
blocks for all of the shell command, shell output, and log output
examples.

Add dm-dust to index.rst.

Additionally, fix an annotation in the "querying for specific bad
blocks" section, on the "queryblock ... not found in badblocklist"
example, to properly state that the message appears when a given
block is not found.

Signed-off-by: Bryan Gurney <bgurney@redhat.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-10 11:37:16 -06:00
Nikos Tsironis 7431b7835f dm: add clone target
Add the dm-clone target, which allows cloning of arbitrary block
devices.

dm-clone produces a one-to-one copy of an existing, read-only source
device into a writable destination device: It presents a virtual block
device which makes all data appear immediately, and redirects reads and
writes accordingly.

The main use case of dm-clone is to clone a potentially remote,
high-latency, read-only, archival-type block device into a writable,
fast, primary-type device for fast, low-latency I/O. The cloned device
is visible/mountable immediately and the copy of the source device to
the destination device happens in the background, in parallel with user
I/O.

When the cloning completes, the dm-clone table can be removed altogether
and be replaced, e.g., by a linear table, mapping directly to the
destination device.

For further information and examples of how to use dm-clone, please read
Documentation/admin-guide/device-mapper/dm-clone.rst

Suggested-by: Vangelis Koukis <vkoukis@arrikto.com>
Co-developed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-09-12 09:32:31 -04:00
Jaskaran Khurana 88cd3e6cfa dm verity: add root hash pkcs#7 signature verification
The verification is to support cases where the root hash is not secured
by Trusted Boot, UEFI Secureboot or similar technologies.

One of the use cases for this is for dm-verity volumes mounted after
boot, the root hash provided during the creation of the dm-verity volume
has to be secure and thus in-kernel validation implemented here will be
used before we trust the root hash and allow the block device to be
created.

The signature being provided for verification must verify the root hash
and must be trusted by the builtin keyring for verification to succeed.

The hash is added as a key of type "user" and the description is passed
to the kernel so it can look it up and use it for verification.

Adds CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG which can be turned on if root
hash verification is needed.

Kernel commandline dm_verity module parameter 'require_signatures' will
indicate whether to force root hash signature verification (for all dm
verity volumes).

Signed-off-by: Jaskaran Khurana <jaskarankhurana@linux.microsoft.com>
Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-08-23 10:13:14 -04:00
Mauro Carvalho Chehab 4f4cfa6c56 docs: admin-guide: add a series of orphaned documents
There are lots of documents that belong to the admin-guide but
are on random places (most under Documentation root dir).

Move them to the admin guide.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2019-07-15 11:03:02 -03:00
Mauro Carvalho Chehab 6cf2a73cb2 docs: device-mapper: move it to the admin-guide
The DM support describes lots of aspects related to mapped
disk partitions from the userspace PoV.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:01 -03:00