dm-delay: support zoned devices

Add support for zoned device by passing through report_zoned to the
underlying read device.

This is required to make enable xfstests xfs/311 on zoned devices.

Signe

dm-delay: support zoned devices

Add support for zoned device by passing through report_zoned to the
underlying read device.

This is required to make enable xfstests xfs/311 on zoned devices.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>

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dm-delay: remove timer_lock

Instead of manually checking the timer details in queue_timeout(), call
timer_reduce() to start the timer or reduce the expiration time. This
avoids needing a lock.

Sign

dm-delay: remove timer_lock

Instead of manually checking the timer details in queue_timeout(), call
timer_reduce() to start the timer or reduce the expiration time. This
avoids needing a lock.

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

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dm-delay: change locking to avoid contention

The delayed_bios list is protected by one mutex shared by all dm-delay
devices. This mutex must be held whenever a bio is added or expired bios
are remov

dm-delay: change locking to avoid contention

The delayed_bios list is protected by one mutex shared by all dm-delay
devices. This mutex must be held whenever a bio is added or expired bios
are removed from the list. Since a large number of expired bios could
be on the list, flush_delayed_bios() can schedule while holding the
mutex. This means a flush_delayed_bios() call on any dm-delay device can
slow down delay_map() calls on any other dm-delay device.

To keep dm-delay devices from slowing each other down and keep
processing delay bios from slowing adding delayed bios, the global mutex
has been removed, and each dm-delay device now has two locks.
delayed_bios_lock is a spinlock that must be held whenever the
delayed_bios list is accessed. process_bios_lock is a mutex that must be
held whenever a process has temporarily pulled bios off the delayed_bios
list to check which ones should be processed. It must be held until all
the bios that won't be processed are returned to the list. This is what
flush_delayed_bios() now does. The mutex is necessary to guarantee that
delay_presuspend() sees the entire list of delayed bios when it calls
flush_delayed_bios().

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

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dm-delay: fix max_delay calculations

delay_ctr() pointlessly compared max_delay in cases where multiple delay
classes were initialized identically. Also, when write delays were
configured different

dm-delay: fix max_delay calculations

delay_ctr() pointlessly compared max_delay in cases where multiple delay
classes were initialized identically. Also, when write delays were
configured different than read delays, delay_ctr() never compared their
value against max_delay. Fix these issues.

Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq")
Signed-off-by: Benjamin Marzinski <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm-delay: fix hung task introduced by kthread mode

If the worker thread is not woken due to a bio, then it is not woken at
all. This causes the hung task check to trigger. This occurs, for
instance,

dm-delay: fix hung task introduced by kthread mode

If the worker thread is not woken due to a bio, then it is not woken at
all. This causes the hung task check to trigger. This occurs, for
instance, when no bios are submitted. Also when a delay of 0 is
configured, delay_bio() returns without waking the worker.

Prevent the hung task check from triggering by creating the thread with
kthread_run() instead of using kthread_create() directly.

Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq")
Signed-off-by: Joel Colledge <[email protected]>
Reviewed-by: Benjamin Marzinski <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm-delay: fix workqueue delay_timer race

delay_timer could be pending when delay_dtr() is called. It needs to be
shut down before kdelayd_wq is destroyed, so it won't try queueing more
work to kdela

dm-delay: fix workqueue delay_timer race

delay_timer could be pending when delay_dtr() is called. It needs to be
shut down before kdelayd_wq is destroyed, so it won't try queueing more
work to kdelayd_wq while that's getting destroyed.

Also the del_timer_sync() call in delay_presuspend() doesn't protect
against the timer getting immediately rearmed by the queued call to
flush_delayed_bios(), but there's no real harm if that does happen.
timer_delete() is less work, and is basically just as likely to stop a
pointless call to flush_delayed_bios().

Fixes: 26b9f228703f ("dm: delay target")
Signed-off-by: Benjamin Marzinski <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm-delay: avoid duplicate logic

This is small refactoring of dm-delay - we avoid duplicate logic in
flush_delayed_bios and flush_delayed_bios_fast and join these two
functions into one.

We also add

dm-delay: avoid duplicate logic

This is small refactoring of dm-delay - we avoid duplicate logic in
flush_delayed_bios and flush_delayed_bios_fast and join these two
functions into one.

We also add cond_resched() to flush_delayed_bios because the list may have
unbounded number of entries.

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

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dm-delay: fix bugs introduced by kthread mode

This commit fixes the following bugs introduced by commit 70bbeb29fab0
("dm delay: for short delays, use kthread instead of timers and wq"):

* the func

dm-delay: fix bugs introduced by kthread mode

This commit fixes the following bugs introduced by commit 70bbeb29fab0
("dm delay: for short delays, use kthread instead of timers and wq"):

* the function flush_worker_fn has no exit path - on unload, this
function will just loop and consume 100% CPU without any progress

* the wake-up mechanism in flush_worker_fn is racy - a wake up will be
missed if the process adds entries to the delayed_bios list just
before set_current_state(TASK_INTERRUPTIBLE)

* flush_delayed_bios_fast submits a bio while holding a global mutex;
this may deadlock if we have multiple stacked dm-delay devices and
the underlying device attempts to acquire the mutex too

* if the target constructor fails, it will call delay_dtr. delay_dtr
would attempt to free dc->timer_lock without it being initialized by
the constructor.

* if the target constructor's kthread allocation fails, delay_dtr
would crash trying to dereference dc->worker because it is non-NULL
due to ERR_PTR.

Fixes: 70bbeb29fab0 ("dm delay: for short delays, use kthread instead of timers and wq")
Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm-delay: fix a race between delay_presuspend and delay_bio

In delay_presuspend, we set the atomic variable may_delay and then stop
the timer and flush pending bios. The intention here is to prevent

dm-delay: fix a race between delay_presuspend and delay_bio

In delay_presuspend, we set the atomic variable may_delay and then stop
the timer and flush pending bios. The intention here is to prevent the
delay target from re-arming the timer again.

However, this test is racy. Suppose that one thread goes to delay_bio,
sees that dc->may_delay is one and proceeds; now, another thread executes
delay_presuspend, it sets dc->may_delay to zero, deletes the timer and
flushes pending bios. Then, the first thread continues and adds the bio to
delayed->list despite the fact that dc->may_delay is false.

Fix this bug by changing may_delay's type from atomic_t to bool and
only access it while holding the delayed_bios_lock mutex. Note that we
don't have to grab the mutex in delay_resume because there are no bios
in flight at this point.

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

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dm delay: for short delays, use kthread instead of timers and wq

DM delay's current design of using timers and wq to realize the delays
is insufficient for delays below ~50ms.

This commit enhances

dm delay: for short delays, use kthread instead of timers and wq

DM delay's current design of using timers and wq to realize the delays
is insufficient for delays below ~50ms.

This commit enhances the design to use a kthread to flush the expired
delays, trading some CPU time (in some cases) for better delay
accuracy and delays closer to what the user requested for smaller
delays. The new design is chosen as long as all the delays are below
50ms.

Since bios can't be completed in interrupt context using a kthread
is probably the most reasonable way to approach this.

Testing with
echo "0 2097152 zero" | dmsetup create dm-zeros
for i in $(seq 0 20);
do
echo "0 2097152 delay /dev/mapper/dm-zeros 0 $i" | dmsetup create dm-delay-${i}ms;
done

Some performance numbers for comparison, on beaglebone black (single
core) CONFIG_HZ_1000=y:

fio --name=1msread --rw=randread --bs=4k --runtime=60 --time_based \
--filename=/dev/mapper/dm-delay-1ms
Theoretical maximum: 1000 IOPS
Previous: 250 IOPS
Kthread: 500 IOPS

fio --name=10msread --rw=randread --bs=4k --runtime=60 --time_based \
--filename=/dev/mapper/dm-delay-10ms
Theoretical maximum: 100 IOPS
Previous: 45 IOPS
Kthread: 50 IOPS

fio --name=1mswrite --rw=randwrite --direct=1 --bs=4k --runtime=60 \
--time_based --filename=/dev/mapper/dm-delay-1ms
Theoretical maximum: 1000 IOPS
Previous: 498 IOPS
Kthread: 1000 IOPS

fio --name=10mswrite --rw=randwrite --direct=1 --bs=4k --runtime=60 \
--time_based --filename=/dev/mapper/dm-delay-10ms
Theoretical maximum: 100 IOPS
Previous: 90 IOPS
Kthread: 100 IOPS

(This one is just to prove the new design isn't impacting throughput,
not really about delays):
fio --name=10mswriteasync --rw=randwrite --direct=1 --bs=4k \
--runtime=60 --time_based --filename=/dev/mapper/dm-delay-10ms \
--numjobs=32 --iodepth=64 --ioengine=libaio --group_reporting
Previous: 13.3k IOPS
Kthread: 13.3k IOPS

Signed-off-by: Christian Loehle <[email protected]>
[Harshit: kthread_create error handling fix in delay_ctr]
Signed-off-by: Harshit Mogalapalli <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm: add helper macro for simple DM target module init and exit

Eliminate duplicate boilerplate code for simple modules that contain
a single DM target driver without any additional setup code.

Add

dm: add helper macro for simple DM target module init and exit

Eliminate duplicate boilerplate code for simple modules that contain
a single DM target driver without any additional setup code.

Add a new module_dm() macro, which replaces the module_init() and
module_exit() with template functions that call dm_register_target()
and dm_unregister_target() respectively.

Signed-off-by: Yangtao Li <[email protected]>
Signed-off-by: Mike Snitzer <[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: change "unsigned" to "unsigned int"

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: simplify basic targets

Remove needless factoring and remap bi_sector regardless of
bio_sectors() being non-zero.

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

dm: simplify dm_sumbit_bio_remap interface

Remove the from_wq argument from dm_sumbit_bio_remap(). Eliminates the
need for dm_sumbit_bio_remap() callers to know whether they are
calling for a workqu

dm: simplify dm_sumbit_bio_remap interface

Remove the from_wq argument from dm_sumbit_bio_remap(). Eliminates the
need for dm_sumbit_bio_remap() callers to know whether they are
calling for a workqueue or from the original dm_submit_bio().

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

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

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

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dm delay: use dm_submit_bio_remap

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

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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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 delay: fix a crash when invalid device is specified

When the target line contains an invalid device, delay_ctr() will call
delay_dtr() with NULL workqueue. Attempting to destroy the NULL
workque

dm delay: fix a crash when invalid device is specified

When the target line contains an invalid device, delay_ctr() will call
delay_dtr() with NULL workqueue. Attempting to destroy the NULL
workqueue causes a crash.

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

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dm: Check for device sector overflow if CONFIG_LBDAF is not set

Reference to a device in device-mapper table contains offset in sectors.

If the sector_t is 32bit integer (CONFIG_LBDAF is not set),

dm: Check for device sector overflow if CONFIG_LBDAF is not set

Reference to a device in device-mapper table contains offset in sectors.

If the sector_t is 32bit integer (CONFIG_LBDAF is not set), then
several device-mapper targets can overflow this offset and validity
check is then performed on a wrong offset and a wrong table is activated.

See for example (on 32bit without CONFIG_LBDAF) this overflow:

# dmsetup create test --table "0 2048 linear /dev/sdg 4294967297"
# dmsetup table test
0 2048 linear 8:96 1

This patch adds explicit check for overflow if the offset is sector_t type.

Signed-off-by: Milan Broz <[email protected]>
Reviewed-by: Mikulas Patocka <[email protected]>
Signed-off-by: Mike Snitzer <[email protected]>

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dm delay: add flush as a third class of IO

Add a new class for dm-delay that delays flush requests. Previously,
flushes were delayed as writes, but it caused problems if the user
needed to create a

dm delay: add flush as a third class of IO

Add a new class for dm-delay that delays flush requests. Previously,
flushes were delayed as writes, but it caused problems if the user
needed to create a device with one or a few slow sectors for the purpose
of testing - all flushes would be forwarded to this device and delayed,
and that skews the test results. Fix this by allowing to select 0 delay
for flushes.

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

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dm delay: refactor repetitive code

dm-delay has a lot of code that is repeated for delaying read and write
bios. Repetitive code is generally bad; refactor out the repetitive
code in preperation fo

dm delay: refactor repetitive code

dm-delay has a lot of code that is repeated for delaying read and write
bios. Repetitive code is generally bad; refactor out the repetitive
code in preperation for adding another delay class for flush bios.

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

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dm: backfill missing calls to mutex_destroy()

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

md: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pas

md: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Kent Overstreet <[email protected]>
Cc: Shaohua Li <[email protected]>
Cc: Alasdair Kergon <[email protected]>
Cc: Mike Snitzer <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Michael Lyle <[email protected]>
Reviewed-by: Mike Snitzer <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

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