linux.git/drivers/md/dm-cache-target.c, branch v5.13

dm cache: remove needless request_queue NULL pointer checks

2021-03-26T18:53:42+00:00

Since commit ff9ea323816d ("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 
Signed-off-by: Mike Snitzer

dm cache: simplify the return expression of load_mapping()

2020-12-22T14:54:48+00:00

Simplify the return expression.

Signed-off-by: Zheng Yongjun 
Signed-off-by: Mike Snitzer

Revert "dm cache: fix arm link errors with inline"

2020-12-01T20:43:36+00:00

This reverts commit 43aeaa29573924df76f44eda2bbd94ca36e407b5.

Since commit 0bddd227f3dc ("Documentation: update for gcc 4.9 requirement")
the minimum supported version of GCC is gcc-4.9. It's now safe to remove
this code.

Link: https://github.com/ClangBuiltLinux/linux/issues/427
Signed-off-by: Nick Desaulniers 
Acked-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm: use dm_table_get_device_name() where appropriate in targets

2020-09-29T20:33:08+00:00

dm_table_get_device_name() avoids calling dm_table_get_md() followed by
dm_device_name() -- saves intermediate dm_table_get_md() call.

Signed-off-by: Mike Snitzer

writeback: remove bdi->congested_fn

2020-07-08T23:20:46+00:00

Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures.  And
pktdvd is a deprecated driver that isn't useful in stack setup
either.  So remove the dead congested_fn stacking infrastructure.

Signed-off-by: Christoph Hellwig 
Acked-by: Song Liu 
Acked-by: David Sterba 
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe

block: rename generic_make_request to submit_bio_noacct

2020-07-01T13:27:24+00:00

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 
Signed-off-by: Jens Axboe

dm: bump version of core and various targets

2020-03-03T16:10:21+00:00

Changes made during the 5.6 cycle warrant bumping the version number
for DM core and the targets modified by this commit.

It should be noted that dm-thin, dm-crypt and dm-raid already had
their target version bumped during the 5.6 merge window.

Signed-off-by; Mike Snitzer

dm cache: fix a crash due to incorrect work item cancelling

2020-02-27T17:00:52+00:00

The crash can be reproduced by running the lvm2 testsuite test
lvconvert-thin-external-cache.sh for several minutes, e.g.:
  while :; do make check T=shell/lvconvert-thin-external-cache.sh; done

The crash happens in this call chain:
do_waker -> policy_tick -> smq_tick -> end_hotspot_period -> clear_bitset
-> memset -> __memset -- which accesses an invalid pointer in the vmalloc
area.

The work entry on the workqueue is executed even after the bitmap was
freed. The problem is that cancel_delayed_work doesn't wait for the
running work item to finish, so the work item can continue running and
re-submitting itself even after cache_postsuspend. In order to make sure
that the work item won't be running, we must use cancel_delayed_work_sync.

Also, change flush_workqueue to drain_workqueue, so that if some work item
submits itself or another work item, we are properly waiting for both of
them.

Fixes: c6b4fcbad044 ("dm: add cache target")
Cc: stable@vger.kernel.org # v3.9
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm cache: replace spin_lock_irqsave with spin_lock_irq

2019-11-05T19:53:04+00:00

If we are in a place where it is known that interrupts are enabled,
functions spin_lock_irq/spin_unlock_irq should be used instead of
spin_lock_irqsave/spin_unlock_irqrestore.

spin_lock_irq and spin_unlock_irq are faster because they don't need to
push and pop the flags register.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm cache: fix bugs when a GFP_NOWAIT allocation fails

2019-10-17T15:13:50+00:00

GFP_NOWAIT allocation can fail anytime - it doesn't wait for memory being
available and it fails if the mempool is exhausted and there is not enough
memory.

If we go down this path:
  map_bio -> mg_start -> alloc_migration -> mempool_alloc(GFP_NOWAIT)
we can see that map_bio() doesn't check the return value of mg_start(),
and the bio is leaked.

If we go down this path:
  map_bio -> mg_start -> mg_lock_writes -> alloc_prison_cell ->
  dm_bio_prison_alloc_cell_v2 -> mempool_alloc(GFP_NOWAIT) ->
  mg_lock_writes -> mg_complete
the bio is ended with an error - it is unacceptable because it could
cause filesystem corruption if the machine ran out of memory
temporarily.

Change GFP_NOWAIT to GFP_NOIO, so that the mempool code will properly
wait until memory becomes available. mempool_alloc with GFP_NOIO can't
fail, so remove the code paths that deal with allocation failure.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer