Otherwise most non-x86 architectures (e.g. riscv, arm) will resort to
byte-by-byte access.
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove this extra BUG_ON() that calls node_check() -- which avoids extra crc checking.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Both sm_disk_new_block and sm_disk_commit are needlessly calling
sm_disk_get_nr_free(). Looks like old queries used for some
debugging.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add a new flag "reset_recalculate" that will restart recalculating
from the beginning of the device. It can be used if we want to change
the hash function. Example:
dmsetup remove_all
rmmod brd
set -e
modprobe brd rd_size=1048576
dmsetup create in --table '0 2000000 integrity /dev/ram0 0 16 J 2 internal_hash:sha256 recalculate'
sleep 10
dmsetup status
dmsetup remove in
dmsetup create in --table '0 2000000 integrity /dev/ram0 0 16 J 2 internal_hash:sha3-256 reset_recalculate'
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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>
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>
These are only used by DM core, DM target modules should only use
dm_{get,put}_device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If we set non-empty param->name or param->uuid on the DM_LIST_DEVICES_CMD
ioctl, the set values are considered filter prefixes. The ioctl will only
return entries with matching name or uuid prefix.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When LVM needs to find a device with a particular UUID it needs to ask for
UUID for each device. This patch returns UUID directly in the list of
devices, so that LVM doesn't have to query all the devices with an ioctl.
The UUID is returned if the flag DM_UUID_FLAG is set in the parameters.
Returning UUID is done in backward-compatible way. There's one unused
32-bit word value after the event number. This patch sets the bit
DM_NAME_LIST_FLAG_HAS_UUID if UUID is present and
DM_NAME_LIST_FLAG_DOESNT_HAVE_UUID if it isn't (if none of these bits is
set, then we have an old kernel that doesn't support returning UUIDs). The
UUID is stored after this word. The 'next' value is updated to point after
the UUID, so that old version of libdevmapper will skip the UUID without
attempting to interpret it.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
For high numbers of DM devices the 64-entry hash table has non-trivial
overhead. Fix this by replacing the hash table with a red-black tree.
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If more than one one handling mode is requested during DM verity table
load, the last requested mode will be used.
Change this to impose more strict checking so that the table load will
fail if more than one error handling mode is requested.
Signed-off-by: JeongHyeon Lee <jhs2.lee@samsung.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove useless "while" loop. If the condition ci.sector_count && !error is
true, we go to a branch that ends with "break". If this condition is
false, the "while" loop will not be executed again. So, the loop can't be
executed more than once.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Zero-length and one-element arrays are deprecated, see
Documentation/process/deprecated.rst
Flexible-array members should be used instead.
Generated by: scripts/coccinelle/misc/flexible_array.cocci
CC: Denis Efremov <efremov@linux.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If there are not any dm devices, we need to zero the "dev" argument in
the first structure dm_name_list. However, this can cause out of
bounds write, because the "needed" variable is zero and len may be
less than eight.
Fix this bug by reporting DM_BUFFER_FULL_FLAG if the result buffer is
too small to hold the "nl->dev" value.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When a DM device is first created it doesn't yet have an established
capacity, therefore the use of set_capacity_and_notify() should be
conditional given the potential for needless pr_info "detected
capacity change" noise even if capacity is 0.
One could argue that the pr_info() in set_capacity_and_notify() is
misplaced, but that position is not held uniformly.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: f64d9b2eac ("dm: use set_capacity_and_notify")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Commit 24f6b6036c ("dm table: fix zoned iterate_devices based device
capability checks") triggered dm table load failure when dm-zoned device
is set up for zoned block devices and a regular device for cache.
The commit inverted logic of two callback functions for iterate_devices:
device_is_zoned_model() and device_matches_zone_sectors(). The logic of
device_is_zoned_model() was inverted then all destination devices of all
targets in dm table are required to have the expected zoned model. This
is fine for dm-linear, dm-flakey and dm-crypt on zoned block devices
since each target has only one destination device. However, this results
in failure for dm-zoned with regular cache device since that target has
both regular block device and zoned block devices.
As for device_matches_zone_sectors(), the commit inverted the logic to
require all zoned block devices in each target have the specified
zone_sectors. This check also fails for regular block device which does
not have zones.
To avoid the check failures, fix the zone model check and the zone
sectors check. For zone model check, introduce the new feature flag
DM_TARGET_MIXED_ZONED_MODEL, and set it to dm-zoned target. When the
target has this flag, allow it to have destination devices with any
zoned model. For zone sectors check, skip the check if the destination
device is not a zoned block device. Also add comments and improve an
error message to clarify expectations to the two checks.
Fixes: 24f6b6036c ("dm table: fix zoned iterate_devices based device capability checks")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Three optional parameters must be accepted at once in a DM verity table, e.g.:
(verity_error_handling_mode) (ignore_zero_block) (check_at_most_once)
Fix this to be possible by incrementing DM_VERITY_OPTS_MAX.
Signed-off-by: JeongHyeon Lee <jhs2.lee@samsung.com>
Fixes: 843f38d382 ("dm verity: add 'check_at_most_once' option to only validate hashes once")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Merge tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Mostly just random fixes all over the map.
The only odd-one-out change is finally getting the rename of
BIO_MAX_PAGES to BIO_MAX_VECS done. This should've been done with the
multipage bvec change, but it's been left.
Do it now to avoid hassles around changes piling up for the next merge
window.
Summary:
- NVMe pull request:
- one more quirk (Dmitry Monakhov)
- fix max_zone_append_sectors initialization (Chaitanya Kulkarni)
- nvme-fc reset/create race fix (James Smart)
- fix status code on aborts/resets (Hannes Reinecke)
- fix the CSS check for ZNS namespaces (Chaitanya Kulkarni)
- fix a use after free in a debug printk in nvme-rdma (Lv Yunlong)
- Follow-up NVMe error fix for NULL 'id' (Christoph)
- Fixup for the bd_size_lock being IRQ safe, now that the offending
driver has been dropped (Damien).
- rsxx probe failure error return (Jia-Ju)
- umem probe failure error return (Wei)
- s390/dasd unbind fixes (Stefan)
- blk-cgroup stats summing fix (Xunlei)
- zone reset handling fix (Damien)
- Rename BIO_MAX_PAGES to BIO_MAX_VECS (Christoph)
- Suppress uevent trigger for hidden devices (Daniel)
- Fix handling of discard on busy device (Jan)
- Fix stale cache issue with zone reset (Shin'ichiro)"
* tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-block:
nvme: fix the nsid value to print in nvme_validate_or_alloc_ns
block: Discard page cache of zone reset target range
block: Suppress uevent for hidden device when removed
block: rename BIO_MAX_PAGES to BIO_MAX_VECS
nvme-pci: add the DISABLE_WRITE_ZEROES quirk for a Samsung PM1725a
nvme-rdma: Fix a use after free in nvmet_rdma_write_data_done
nvme-core: check ctrl css before setting up zns
nvme-fc: fix racing controller reset and create association
nvme-fc: return NVME_SC_HOST_ABORTED_CMD when a command has been aborted
nvme-fc: set NVME_REQ_CANCELLED in nvme_fc_terminate_exchange()
nvme: add NVME_REQ_CANCELLED flag in nvme_cancel_request()
nvme: simplify error logic in nvme_validate_ns()
nvme: set max_zone_append_sectors nvme_revalidate_zones
block: rsxx: fix error return code of rsxx_pci_probe()
block: Fix REQ_OP_ZONE_RESET_ALL handling
umem: fix error return code in mm_pci_probe()
blk-cgroup: Fix the recursive blkg rwstat
s390/dasd: fix hanging IO request during DASD driver unbind
s390/dasd: fix hanging DASD driver unbind
block: Try to handle busy underlying device on discard
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reed-Solomon roots that are unaligned to block size.
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Merge tag 'for-5.12/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 verity target's optional Forward Error Correction (FEC) for
Reed-Solomon roots that are unaligned to block size"
* tag 'for-5.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm verity: fix FEC for RS roots unaligned to block size
dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size
Optional Forward Error Correction (FEC) code in dm-verity uses
Reed-Solomon code and should support roots from 2 to 24.
The error correction parity bytes (of roots lengths per RS block) are
stored on a separate device in sequence without any padding.
Currently, to access FEC device, the dm-verity-fec code uses dm-bufio
client with block size set to verity data block (usually 4096 or 512
bytes).
Because this block size is not divisible by some (most!) of the roots
supported lengths, data repair cannot work for partially stored parity
bytes.
This fix changes FEC device dm-bufio block size to "roots << SECTOR_SHIFT"
where we can be sure that the full parity data is always available.
(There cannot be partial FEC blocks because parity must cover whole
sectors.)
Because the optional FEC starting offset could be unaligned to this
new block size, we have to use dm_bufio_set_sector_offset() to
configure it.
The problem is easily reproduced using veritysetup, e.g. for roots=13:
# create verity device with RS FEC
dd if=/dev/urandom of=data.img bs=4096 count=8 status=none
veritysetup format data.img hash.img --fec-device=fec.img --fec-roots=13 | awk '/^Root hash/{ print $3 }' >roothash
# create an erasure that should be always repairable with this roots setting
dd if=/dev/zero of=data.img conv=notrunc bs=1 count=8 seek=4088 status=none
# try to read it through dm-verity
veritysetup open data.img test hash.img --fec-device=fec.img --fec-roots=13 $(cat roothash)
dd if=/dev/mapper/test of=/dev/null bs=4096 status=noxfer
# wait for possible recursive recovery in kernel
udevadm settle
veritysetup close test
With this fix, errors are properly repaired.
device-mapper: verity-fec: 7:1: FEC 0: corrected 8 errors
...
Without it, FEC code usually ends on unrecoverable failure in RS decoder:
device-mapper: verity-fec: 7:1: FEC 0: failed to correct: -74
...
This problem is present in all kernels since the FEC code's
introduction (kernel 4.5).
It is thought that this problem is not visible in Android ecosystem
because it always uses a default RS roots=2.
Depends-on: a14e5ec66a ("dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Tested-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Cc: stable@vger.kernel.org # 4.5+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm_bufio_get_device_size returns the device size in blocks. Before
returning the value, we must subtract the nubmer of starting
sectors. The number of starting sectors may not be divisible by block
size.
Note that currently, no target is using dm_bufio_set_sector_offset and
dm_bufio_get_device_size simultaneously, so this change has no effect.
However, an upcoming dm-verity-fec fix needs this change.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Milan Broz <gmazyland@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block
Pull more block updates from Jens Axboe:
"A few stragglers (and one due to me missing it originally), and fixes
for changes in this merge window mostly. In particular:
- blktrace cleanups (Chaitanya, Greg)
- Kill dead blk_pm_* functions (Bart)
- Fixes for the bio alloc changes (Christoph)
- Fix for the partition changes (Christoph, Ming)
- Fix for turning off iopoll with polled IO inflight (Jeffle)
- nbd disconnect fix (Josef)
- loop fsync error fix (Mauricio)
- kyber update depth fix (Yang)
- max_sectors alignment fix (Mikulas)
- Add bio_max_segs helper (Matthew)"
* tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block: (21 commits)
block: Add bio_max_segs
blktrace: fix documentation for blk_fill_rw()
block: memory allocations in bounce_clone_bio must not fail
block: remove the gfp_mask argument to bounce_clone_bio
block: fix bounce_clone_bio for passthrough bios
block-crypto-fallback: use a bio_set for splitting bios
block: fix logging on capacity change
blk-settings: align max_sectors on "logical_block_size" boundary
block: reopen the device in blkdev_reread_part
block: don't skip empty device in in disk_uevent
blktrace: remove debugfs file dentries from struct blk_trace
nbd: handle device refs for DESTROY_ON_DISCONNECT properly
kyber: introduce kyber_depth_updated()
loop: fix I/O error on fsync() in detached loop devices
block: fix potential IO hang when turning off io_poll
block: get rid of the trace rq insert wrapper
blktrace: fix blk_rq_merge documentation
blktrace: fix blk_rq_issue documentation
blktrace: add blk_fill_rwbs documentation comment
block: remove superfluous param in blk_fill_rwbs()
...
It's often inconvenient to use BIO_MAX_PAGES due to min() requiring the
sign to be the same. Introduce bio_max_segs() and change BIO_MAX_PAGES to
be unsigned to make it easier for the users.
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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
...
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Merge tag 'for-5.12/drivers-2021-02-17' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
- Remove the skd driver. It's been EOL for a long time (Damien)
- NVMe pull requests
- fix multipath handling of ->queue_rq errors (Chao Leng)
- nvmet cleanups (Chaitanya Kulkarni)
- add a quirk for buggy Amazon controller (Filippo Sironi)
- avoid devm allocations in nvme-hwmon that don't interact well
with fabrics (Hannes Reinecke)
- sysfs cleanups (Jiapeng Chong)
- fix nr_zones for multipath (Keith Busch)
- nvme-tcp crash fix for no-data commands (Sagi Grimberg)
- nvmet-tcp fixes (Sagi Grimberg)
- add a missing __rcu annotation (Christoph)
- failed reconnect fixes (Chao Leng)
- various tracing improvements (Michal Krakowiak, Johannes
Thumshirn)
- switch the nvmet-fc assoc_list to use RCU protection (Leonid
Ravich)
- resync the status codes with the latest spec (Max Gurtovoy)
- minor nvme-tcp improvements (Sagi Grimberg)
- various cleanups (Rikard Falkeborn, Minwoo Im, Chaitanya
Kulkarni, Israel Rukshin)
- Floppy O_NDELAY fix (Denis)
- MD pull request
- raid5 chunk_sectors fix (Guoqing)
- Use lore links (Kees)
- Use DEFINE_SHOW_ATTRIBUTE for nbd (Liao)
- loop lock scaling (Pavel)
- mtip32xx PCI fixes (Bjorn)
- bcache fixes (Kai, Dongdong)
- Misc fixes (Tian, Yang, Guoqing, Joe, Andy)
* tag 'for-5.12/drivers-2021-02-17' of git://git.kernel.dk/linux-block: (64 commits)
lightnvm: pblk: Replace guid_copy() with export_guid()/import_guid()
lightnvm: fix unnecessary NULL check warnings
nvme-tcp: fix crash triggered with a dataless request submission
block: Replace lkml.org links with lore
nbd: Convert to DEFINE_SHOW_ATTRIBUTE
nvme: add 48-bit DMA address quirk for Amazon NVMe controllers
nvme-hwmon: rework to avoid devm allocation
nvmet: remove else at the end of the function
nvmet: add nvmet_req_subsys() helper
nvmet: use min of device_path and disk len
nvmet: use invalid cmd opcode helper
nvmet: use invalid cmd opcode helper
nvmet: add helper to report invalid opcode
nvmet: remove extra variable in id-ns handler
nvmet: make nvmet_find_namespace() req based
nvmet: return uniform error for invalid ns
nvmet: set status to 0 in case for invalid nsid
nvmet-fc: add a missing __rcu annotation to nvmet_fc_tgt_assoc.queues
nvme-multipath: set nr_zones for zoned namespaces
nvmet-tcp: fix potential race of tcp socket closing accept_work
...
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Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Another nice round of removing more code than what is added, mostly
due to Christoph's relentless pursuit of tech debt removal/cleanups.
This pull request contains:
- Two series of BFQ improvements (Paolo, Jan, Jia)
- Block iov_iter improvements (Pavel)
- bsg error path fix (Pan)
- blk-mq scheduler improvements (Jan)
- -EBUSY discard fix (Jan)
- bvec allocation improvements (Ming, Christoph)
- bio allocation and init improvements (Christoph)
- Store bdev pointer in bio instead of gendisk + partno (Christoph)
- Block trace point cleanups (Christoph)
- hard read-only vs read-only split (Christoph)
- Block based swap cleanups (Christoph)
- Zoned write granularity support (Damien)
- Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"
* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
mm: simplify swapdev_block
sd_zbc: clear zone resources for non-zoned case
block: introduce blk_queue_clear_zone_settings()
zonefs: use zone write granularity as block size
block: introduce zone_write_granularity limit
block: use blk_queue_set_zoned in add_partition()
nullb: use blk_queue_set_zoned() to setup zoned devices
nvme: cleanup zone information initialization
block: document zone_append_max_bytes attribute
block: use bi_max_vecs to find the bvec pool
md/raid10: remove dead code in reshape_request
block: mark the bio as cloned in bio_iov_bvec_set
block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
block: remove a layer of indentation in bio_iov_iter_get_pages
block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
block: remove the 1 and 4 vec bvec_slabs entries
block: streamline bvec_alloc
block: factor out a bvec_alloc_gfp helper
block: move struct biovec_slab to bio.c
block: reuse BIO_INLINE_VECS for integrity bvecs
...
The system would deadlock when swapping to a dm-crypt device. The reason
is that for each incoming write bio, dm-crypt allocates memory that holds
encrypted data. These excessive allocations exhaust all the memory and the
result is either deadlock or OOM trigger.
This patch limits the number of in-flight swap bios, so that the memory
consumed by dm-crypt is limited. The limit is enforced if the target set
the "limit_swap_bios" variable and if the bio has REQ_SWAP set.
Non-swap bios are not affected becuase taking the semaphore would cause
performance degradation.
This is similar to request-based drivers - they will also block when the
number of requests is over the limit.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Allow removal of CONFIG_BLK_DEV_ZONED conditionals in target_type
definition of various targets.
Suggested-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm-linear and dm-flakey obviously can pass through inline crypto support.
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Now that device mapper supports inline encryption, add the ability to
evict keys from all underlying devices. When an upper layer requests
a key eviction, we simply iterate through all underlying devices
and evict that key from each device.
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Update the device-mapper core to support exposing the inline crypto
support of the underlying device(s) through the device-mapper device.
This works by creating a "passthrough keyslot manager" for the dm
device, which declares support for encryption settings which all
underlying devices support. When a supported setting is used, the bio
cloning code handles cloning the crypto context to the bios for all the
underlying devices. When an unsupported setting is used, the blk-crypto
fallback is used as usual.
Crypto support on each underlying device is ignored unless the
corresponding dm target opts into exposing it. This is needed because
for inline crypto to semantically operate on the original bio, the data
must not be transformed by the dm target. Thus, targets like dm-linear
can expose crypto support of the underlying device, but targets like
dm-crypt can't. (dm-crypt could use inline crypto itself, though.)
A DM device's table can only be changed if the "new" inline encryption
capabilities are a (*not* necessarily strict) superset of the "old" inline
encryption capabilities. Attempts to make changes to the table that result
in some inline encryption capability becoming no longer supported will be
rejected.
For the sake of clarity, key eviction from underlying devices will be
handled in a future patch.
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Metadata resize shouldn't happen in the ctr. The ctr loads a temporary
(inactive) table that will only become active upon resume. That is why
resize should always be done in terms of resume. Otherwise a load (ctr)
whose inactive table never becomes active will incorrectly resize the
metadata.
Also, perform the resize directly in preresume, instead of using the
worker to do it.
The worker might run other metadata operations, e.g., it could start
digestion, before resizing the metadata. These operations will end up
using the old size.
This could lead to errors, like:
device-mapper: era: metadata_digest_transcribe_writeset: dm_array_set_value failed
device-mapper: era: process_old_eras: digest step failed, stopping digestion
The reason of the above error is that the worker started the digestion
of the archived writeset using the old, larger size.
As a result, metadata_digest_transcribe_writeset tried to write beyond
the end of the era array.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fix the writeset tree equality test function to use the right value size
when comparing two btree values.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Deallocate the memory allocated for the in-core bitsets when destroying
the target and in error paths.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm-era doesn't support changing the data block size of existing devices,
so check explicitly that the requested block size for a new target
matches the one stored in the metadata.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In case of devices with at most 64 blocks, the digestion of consecutive
eras uses the writeset of the first era as the writeset of all eras to
digest, leading to lost writes. That is, we lose the information about
what blocks were written during the affected eras.
The digestion code uses a dm_disk_bitset object to access the archived
writesets. This structure includes a one word (64-bit) cache to reduce
the number of array lookups.
This structure is initialized only once, in metadata_digest_start(),
when we kick off digestion.
But, when we insert a new writeset into the writeset tree, before the
digestion of the previous writeset is done, or equivalently when there
are multiple writesets in the writeset tree to digest, then all these
writesets are digested using the same cache and the cache is not
re-initialized when moving from one writeset to the next.
For devices with more than 64 blocks, i.e., the size of the cache, the
cache is indirectly invalidated when we move to a next set of blocks, so
we avoid the bug.
But for devices with at most 64 blocks we end up using the same cached
data for digesting all archived writesets, i.e., the cache is loaded
when digesting the first writeset and it never gets reloaded, until the
digestion is done.
As a result, the writeset of the first era to digest is used as the
writeset of all the following archived eras, leading to lost writes.
Fix this by reinitializing the dm_disk_bitset structure, and thus
invalidating the cache, every time the digestion code starts digesting a
new writeset.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In case of a system crash, dm-era might fail to mark blocks as written
in its metadata, although the corresponding writes to these blocks were
passed down to the origin device and completed successfully.
Consider the following sequence of events:
1. We write to a block that has not been yet written in the current era
2. era_map() checks the in-core bitmap for the current era and sees
that the block is not marked as written.
3. The write is deferred for submission after the metadata have been
updated and committed.
4. The worker thread processes the deferred write
(process_deferred_bios()) and marks the block as written in the
in-core bitmap, **before** committing the metadata.
5. The worker thread starts committing the metadata.
6. We do more writes that map to the same block as the write of step (1)
7. era_map() checks the in-core bitmap and sees that the block is marked
as written, **although the metadata have not been committed yet**.
8. These writes are passed down to the origin device immediately and the
device reports them as completed.
9. The system crashes, e.g., power failure, before the commit from step
(5) finishes.
When the system recovers and we query the dm-era target for the list of
written blocks it doesn't report the aforementioned block as written,
although the writes of step (6) completed successfully.
The issue is that era_map() decides whether to defer or not a write
based on non committed information. The root cause of the bug is that we
update the in-core bitmap, **before** committing the metadata.
Fix this by updating the in-core bitmap **after** successfully
committing the metadata.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Following a system crash, dm-era fails to recover the committed writeset
for the current era, leading to lost writes. That is, we lose the
information about what blocks were written during the affected era.
dm-era assumes that the writeset of the current era is archived when the
device is suspended. So, when resuming the device, it just moves on to
the next era, ignoring the committed writeset.
This assumption holds when the device is properly shut down. But, when
the system crashes, the code that suspends the target never runs, so the
writeset for the current era is not archived.
There are three issues that cause the committed writeset to get lost:
1. dm-era doesn't load the committed writeset when opening the metadata
2. The code that resizes the metadata wipes the information about the
committed writeset (assuming it was loaded at step 1)
3. era_preresume() starts a new era, without taking into account that
the current era might not have been archived, due to a system crash.
To fix this:
1. Load the committed writeset when opening the metadata
2. Fix the code that resizes the metadata to make sure it doesn't wipe
the loaded writeset
3. Fix era_preresume() to check for a loaded writeset and archive it,
before starting a new era.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use semicolons and braces.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is potentially long running and not latency sensitive, let's get
it out of the way of other latency sensitive events.
As observed in the previous commit, the `system_wq` comes easily
congested by bcache, and this fixes a few more stalls I was observing
every once in a while.
Let's not make this `WQ_MEM_RECLAIM` as it showed to reduce performance
of boot and file system operations in my tests. Also, without
`WQ_MEM_RECLAIM`, I no longer see desktop stalls. This matches the
previous behavior as `system_wq` also does no memory reclaim:
> // workqueue.c:
> system_wq = alloc_workqueue("events", 0, 0);
Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Before killing `btree_io_wq`, the queue was allocated using
`create_singlethread_workqueue()` which has `WQ_MEM_RECLAIM`. After
killing it, it no longer had this property but `system_wq` is not
single threaded.
Let's combine both worlds and make it multi threaded but able to
reclaim memory.
Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 56b30770b2.
With the btree using the `system_wq`, I seem to see a lot more desktop
latency than I should.
After some more investigation, it looks like the original assumption
of 56b3077 no longer is true, and bcache has a very high potential of
congesting the `system_wq`. In turn, this introduces laggy desktop
performance, IO stalls (at least with btrfs), and input events may be
delayed.
So let's revert this. It's important to note that the semantics of
using `system_wq` previously mean that `btree_io_wq` should be created
before and destroyed after other bcache wqs to keep the same
assumptions.
Cc: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org # 5.4+
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Should be `register_device_async`.
Cc: Coly Li <colyli@suse.de>
Signed-off-by: Kai Krakow <kai@kaishome.de>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Current way to calculate the writeback rate only considered the
dirty sectors, this usually works fine when the fragmentation
is not high, but it will give us unreasonable small rate when
we are under a situation that very few dirty sectors consumed
a lot dirty buckets. In some case, the dirty bucekts can reached
to CUTOFF_WRITEBACK_SYNC while the dirty data(sectors) not even
reached the writeback_percent, the writeback rate will still
be the minimum value (4k), thus it will cause all the writes to be
stucked in a non-writeback mode because of the slow writeback.
We accelerate the rate in 3 stages with different aggressiveness,
the first stage starts when dirty buckets percent reach above
BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW (50), the second is
BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID (57), the third is
BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH (64). By default
the first stage tries to writeback the amount of dirty data
in one bucket (on average) in (1 / (dirty_buckets_percent - 50)) second,
the second stage tries to writeback the amount of dirty data in one bucket
in (1 / (dirty_buckets_percent - 57)) * 100 millisecond, the third
stage tries to writeback the amount of dirty data in one bucket in
(1 / (dirty_buckets_percent - 64)) millisecond.
the initial rate at each stage can be controlled by 3 configurable
parameters writeback_rate_fp_term_{low|mid|high}, they are by default
1, 10, 1000, the hint of IO throughput that these values are trying
to achieve is described by above paragraph, the reason that
I choose those value as default is based on the testing and the
production data, below is some details:
A. When it comes to the low stage, there is still a bit far from the 70
threshold, so we only want to give it a little bit push by setting the
term to 1, it means the initial rate will be 170 if the fragment is 6,
it is calculated by bucket_size/fragment, this rate is very small,
but still much reasonable than the minimum 8.
For a production bcache with unheavy workload, if the cache device
is bigger than 1 TB, it may take hours to consume 1% buckets,
so it is very possible to reclaim enough dirty buckets in this stage,
thus to avoid entering the next stage.
B. If the dirty buckets ratio didn't turn around during the first stage,
it comes to the mid stage, then it is necessary for mid stage
to be more aggressive than low stage, so i choose the initial rate
to be 10 times more than low stage, that means 1700 as the initial
rate if the fragment is 6. This is some normal rate
we usually see for a normal workload when writeback happens
because of writeback_percent.
C. If the dirty buckets ratio didn't turn around during the low and mid
stages, it comes to the third stage, and it is the last chance that
we can turn around to avoid the horrible cutoff writeback sync issue,
then we choose 100 times more aggressive than the mid stage, that
means 170000 as the initial rate if the fragment is 6. This is also
inferred from a production bcache, I've got one week's writeback rate
data from a production bcache which has quite heavy workloads,
again, the writeback is triggered by the writeback percent,
the highest rate area is around 100000 to 240000, so I believe this
kind aggressiveness at this stage is reasonable for production.
And it should be mostly enough because the hint is trying to reclaim
1000 bucket per second, and from that heavy production env,
it is consuming 50 bucket per second on average in one week's data.
Option writeback_consider_fragment is to control whether we want
this feature to be on or off, it's on by default.
Lastly, below is the performance data for all the testing result,
including the data from production env:
https://docs.google.com/document/d/1AmbIEa_2MhB9bqhC3rfga9tp7n9YX9PLn0jSUxscVW0/edit?usp=sharing
Signed-off-by: dongdong tao <dongdong.tao@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Do not attempt to write any data beyond the end of the underlying data
device while shrinking it.
The DM writecache device must be suspended when the underlying data
device is shrunk.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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: Jeffle Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
