dm: always manage discard support in terms of max_hw_discard_sectors

Commit 4f563a64732d ("block: add a max_user_discard_sectors queue
limit") changed block core to set max_discard_sectors to:
min(

dm: always manage discard support in terms of max_hw_discard_sectors

Commit 4f563a64732d ("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 1c0e720228ad ("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 <[email protected]>
Fixes: 1c0e720228ad ("dm: use queue_limits_set")
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: fix lockup in dm_exception_table_exit

There was reported lockup when we exit a snapshot with many exceptions.
Fix this by adding "cond_resched" to the loop that frees the exceptions.

R

dm snapshot: fix lockup in dm_exception_table_exit

There was reported lockup when we exit a snapshot with many exceptions.
Fix this by adding "cond_resched" to the loop that frees the exceptions.

Reported-by: John Pittman <[email protected]>
Cc: [email protected]
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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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.

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 <[email protected]>
Acked-by: Jack Wang <[email protected]> [rnbd]
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Christian Brauner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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dm-snap: simplify the origin_dev == cow_dev check in snapshot_ctr

Use the block_device acquired in dm_get_device for the check instead
of doing an extra lookup.

Signed-off-by: Christoph Hellwig <hc

dm-snap: simplify the origin_dev == cow_dev check in snapshot_ctr

Use the block_device acquired in dm_get_device for the check instead
of doing an extra lookup.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Mike Snitzer <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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dm: push error reporting down to dm_register_target()

Simplifies each DM target's init method by making dm_register_target()
responsible for its error reporting (on behalf of targets).

Signed-off-b

dm: push error reporting down to dm_register_target()

Simplifies each DM target's init method by making dm_register_target()
responsible for its error reporting (on behalf of targets).

Signed-off-by: Yangtao Li <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm: avoid split of quoted strings where possible

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: add missing empty lines

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: avoid spaces before function arguments or in favour of tabs

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: fix trailing statements

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: fix undue/missing spaces

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: correct block comments format.

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: change "unsigned" to "unsigned int"

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm: use fsleep() instead of msleep() for deterministic sleep duration

Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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 <[email protected]>
Signed-off-by: Heinz Mauelsha

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 <[email protected]>
Signed-off-by: Heinz Mauelshagen <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: fix typo in snapshot_map() comment

Signed-off-by: Zhang Jiaming <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

dm-snap: 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 dm_snapshot.

Signed-off-

dm-snap: 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 dm_snapshot.

Signed-off-by: Christoph Hellwig <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

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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 b

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 <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: properly fix a crash when an origin has no snapshots

If an origin target has no snapshots, o->split_boundary is set to 0.
This causes BUG_ON(sectors <= 0) in block/bio.c:bio_split().

F

dm snapshot: properly fix a crash when an origin has no snapshots

If an origin target has no snapshots, o->split_boundary is set to 0.
This causes BUG_ON(sectors <= 0) in block/bio.c:bio_split().

Fix this by initializing chunk_size, and in turn split_boundary, to
rounddown_pow_of_two(UINT_MAX) -- the largest power of two that fits
into "unsigned" type.

Signed-off-by: Mikulas Patocka <[email protected]>
Cc: [email protected]
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: revert "fix a crash when an origin has no snapshots"

Commit 7ee06ddc4038f936b0d4459d37a7d4d844fb03db ("dm snapshot: fix a
crash when an origin has no snapshots") introduced a regression

dm snapshot: revert "fix a crash when an origin has no snapshots"

Commit 7ee06ddc4038f936b0d4459d37a7d4d844fb03db ("dm snapshot: fix a
crash when an origin has no snapshots") introduced a regression in
snapshot merging - causing the lvm2 test lvcreate-cache-snapshot.sh
got stuck in an infinite loop.

Even though commit 7ee06ddc4038f936b0d4459d37a7d4d844fb03db was marked
for stable@ the stable team was notified to _not_ backport it.

Fixes: 7ee06ddc4038 ("dm snapshot: fix a crash when an origin has no snapshots")
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: fix crash with transient storage and zero chunk size

The following commands will crash the kernel:

modprobe brd rd_size=1048576
dmsetup create o --table "0 `blockdev --getsize /dev/ram

dm snapshot: fix crash with transient storage and zero chunk size

The following commands will crash the kernel:

modprobe brd rd_size=1048576
dmsetup create o --table "0 `blockdev --getsize /dev/ram0` snapshot-origin /dev/ram0"
dmsetup create s --table "0 `blockdev --getsize /dev/ram0` snapshot /dev/ram0 /dev/ram1 N 0"

The reason is that when we test for zero chunk size, we jump to the label
bad_read_metadata without setting the "r" variable. The function
snapshot_ctr destroys all the structures and then exits with "r == 0". The
kernel then crashes because it falsely believes that snapshot_ctr
succeeded.

In order to fix the bug, we set the variable "r" to -EINVAL.

Signed-off-by: Mikulas Patocka <[email protected]>
Cc: [email protected]
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: fix a crash when an origin has no snapshots

If an origin target has no snapshots, o->split_boundary is set to 0.
This causes BUG_ON(sectors <= 0) in block/bio.c:bio_split().

Fix this b

dm snapshot: fix a crash when an origin has no snapshots

If an origin target has no snapshots, o->split_boundary is set to 0.
This causes BUG_ON(sectors <= 0) in block/bio.c:bio_split().

Fix this by initializing chunk_size, and in turn split_boundary, to
rounddown_pow_of_two(UINT_MAX) -- the largest power of two that fits
into "unsigned" type.

Reported-by: Michael Tokarev <[email protected]>
Tested-by: Michael Tokarev <[email protected]>
Cc: [email protected]
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm: replace dm_vcalloc()

Use kvcalloc or kvmalloc_array instead (depending whether zeroing is
useful).

Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Mike Snitzer <snit

dm: replace dm_vcalloc()

Use kvcalloc or kvmalloc_array instead (depending whether zeroing is
useful).

Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm snapshot: flush merged data before committing metadata

If the origin device has a volatile write-back cache and the following
events occur:

1: After finishing merge operation of one set of excep

dm snapshot: flush merged data before committing metadata

If the origin device has a volatile write-back cache and the following
events occur:

1: After finishing merge operation of one set of exceptions,
merge_callback() is invoked.
2: Update the metadata in COW device tracking the merge completion.
This update to COW device is flushed cleanly.
3: System crashes and the origin device's cache where the recent
merge was completed has not been flushed.

During the next cycle when we read the metadata from the COW device,
we will skip reading those metadata whose merge was completed in
step (1). This will lead to data loss/corruption.

To address this, flush the origin device post merge IO before
updating the metadata.

Cc: [email protected]
Signed-off-by: Akilesh Kailash <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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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

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 <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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dm snapshot: use true/false for bool variable

Fixes coccicheck warning:

drivers/md/dm-snap.c:1064:3-18: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-snap.c:1152:1-16: WARNING: Assignme

dm snapshot: use true/false for bool variable

Fixes coccicheck warning:

drivers/md/dm-snap.c:1064:3-18: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-snap.c:1152:1-16: WARNING: Assignment of 0/1 to bool variable
drivers/md/dm-snap.c:1317:1-16: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <[email protected]>
Signed-off-by: zhengbin <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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