linux.git/drivers/md/dm.c, branch v5.14

Merge tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2021-07-01T01:19:39+00:00

Pull device mapper updates from Mike Snitzer:

 - Various DM persistent-data library improvements and fixes that
   benefit both the DM thinp and cache targets.

 - A few small DM kcopyd efficiency improvements.

 - Significant zoned related block core, DM core and DM zoned target
   changes that culminate with adding zoned append emulation (which is
   required to properly fix DM crypt's zoned support).

 - Various DM writecache target changes that improve efficiency. Adds an
   optional "metadata_only" feature that only promotes bios flagged with
   REQ_META. But the most significant improvement is writecache's
   ability to pause writeback, for a confiurable time, if/when the
   working set is larger than the cache (and the cache is full) -- this
   ensures performance is no worse than the slower origin device.

* tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits)
  dm writecache: make writeback pause configurable
  dm writecache: pause writeback if cache full and origin being written directly
  dm io tracker: factor out IO tracker
  dm btree remove: assign new_root only when removal succeeds
  dm zone: fix dm_revalidate_zones() memory allocation
  dm ps io affinity: remove redundant continue statement
  dm writecache: add optional "metadata_only" parameter
  dm writecache: add "cleaner" and "max_age" to Documentation
  dm writecache: write at least 4k when committing
  dm writecache: flush origin device when writing and cache is full
  dm writecache: have ssd writeback wait if the kcopyd workqueue is busy
  dm writecache: use list_move instead of list_del/list_add in writecache_writeback()
  dm writecache: commit just one block, not a full page
  dm writecache: remove unused gfp_t argument from wc_add_block()
  dm crypt: Fix zoned block device support
  dm: introduce zone append emulation
  dm: rearrange core declarations for extended use from dm-zone.c
  block: introduce BIO_ZONE_WRITE_LOCKED bio flag
  block: introduce bio zone helpers
  block: improve handling of all zones reset operation
  ...

Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block

2021-06-30T19:12:56+00:00

Pull core block updates from Jens Axboe:

 - disk events cleanup (Christoph)

 - gendisk and request queue allocation simplifications (Christoph)

 - bdev_disk_changed cleanups (Christoph)

 - IO priority improvements (Bart)

 - Chained bio completion trace fix (Edward)

 - blk-wbt fixes (Jan)

 - blk-wbt enable/disable fix (Zhang)

 - Scheduler dispatch improvements (Jan, Ming)

 - Shared tagset scheduler improvements (John)

 - BFQ updates (Paolo, Luca, Pietro)

 - BFQ lock inversion fix (Jan)

 - Documentation improvements (Kir)

 - CLONE_IO block cgroup fix (Tejun)

 - Remove of ancient and deprecated block dump feature (zhangyi)

 - Discard merge fix (Ming)

 - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas,
   Yang)

* tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits)
  block: fix discard request merge
  block/mq-deadline: Remove a WARN_ON_ONCE() call
  blk-mq: update hctx->dispatch_busy in case of real scheduler
  blk: Fix lock inversion between ioc lock and bfqd lock
  bfq: Remove merged request already in bfq_requests_merged()
  block: pass a gendisk to bdev_disk_changed
  block: move bdev_disk_changed
  block: add the events* attributes to disk_attrs
  block: move the disk events code to a separate file
  block: fix trace completion for chained bio
  block/partitions/msdos: Fix typo inidicator -> indicator
  block, bfq: reset waker pointer with shared queues
  block, bfq: check waker only for queues with no in-flight I/O
  block, bfq: avoid delayed merge of async queues
  block, bfq: boost throughput by extending queue-merging times
  block, bfq: consider also creation time in delayed stable merge
  block, bfq: fix delayed stable merge check
  block, bfq: let also stably merged queues enjoy weight raising
  blk-wbt: make sure throttle is enabled properly
  blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled()
  ...

sched: Change task_struct::state

2021-06-18T09:43:09+00:00

Change the type and name of task_struct::state. Drop the volatile and
shrink it to an 'unsigned int'. Rename it in order to find all uses
such that we can use READ_ONCE/WRITE_ONCE as appropriate.

Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Daniel Bristot de Oliveira 
Acked-by: Will Deacon 
Acked-by: Daniel Thompson 
Link: https://lore.kernel.org/r/20210611082838.550736351@infradead.org

dm: introduce zone append emulation

2021-06-04T16:07:37+00:00

For zoned targets that cannot support zone append operations, implement
an emulation using regular write operations. If the original BIO
submitted by the user is a zone append operation, change its clone into
a regular write operation directed at the target zone write pointer
position.

To do so, an array of write pointer offsets (write pointer position
relative to the start of a zone) is added to struct mapped_device. All
operations that modify a sequential zone write pointer (writes, zone
reset, zone finish and zone append) are intersepted in __map_bio() and
processed using the new functions dm_zone_map_bio().

Detection of the target ability to natively support zone append
operations is done from dm_table_set_restrictions() by calling the
function dm_set_zones_restrictions(). A target that does not support
zone append operation, either by explicitly declaring it using the new
struct dm_target field zone_append_not_supported, or because the device
table contains a non-zoned device, has its mapped device marked with the
new flag DMF_ZONE_APPEND_EMULATED. The helper function
dm_emulate_zone_append() is introduced to test a mapped device for this
new flag.

Atomicity of the zones write pointer tracking and updates is done using
a zone write locking mechanism based on a bitmap. This is similar to
the block layer method but based on BIOs rather than struct request.
A zone write lock is taken in dm_zone_map_bio() for any clone BIO with
an operation type that changes the BIO target zone write pointer
position. The zone write lock is released if the clone BIO is failed
before submission or when dm_zone_endio() is called when the clone BIO
completes.

The zone write lock bitmap of the mapped device, together with a bitmap
indicating zone types (conv_zones_bitmap) and the write pointer offset
array (zwp_offset) are allocated and initialized with a full device zone
report in dm_set_zones_restrictions() using the function
dm_revalidate_zones().

For failed operations that may have modified a zone write pointer, the
zone write pointer offset is marked as invalid in dm_zone_endio().
Zones with an invalid write pointer offset are checked and the write
pointer updated using an internal report zone operation when the
faulty zone is accessed again by the user.

All functions added for this emulation have a minimal overhead for
zoned targets natively supporting zone append operations. Regular
device targets are also not affected. The added code also does not
impact builds with CONFIG_BLK_DEV_ZONED disabled by stubbing out all
dm zone related functions.

Signed-off-by: Damien Le Moal 
Reviewed-by: Himanshu Madhani 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Mike Snitzer

dm: rearrange core declarations for extended use from dm-zone.c

2021-06-04T16:07:37+00:00

Move the definitions of struct dm_target_io, struct dm_io and the bits
of the flags field of struct mapped_device from dm.c to dm-core.h to
make them usable from dm-zone.c. For the same reason, declare
dec_pending() in dm-core.h after renaming it to dm_io_dec_pending().
And for symmetry of the function names, introduce the inline helper
dm_io_inc_pending() instead of directly using atomic_inc() calls.

Signed-off-by: Damien Le Moal 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Himanshu Madhani 
Signed-off-by: Mike Snitzer

dm: Forbid requeue of writes to zones

2021-06-04T16:07:33+00:00

A target map method requesting the requeue of a bio with
DM_MAPIO_REQUEUE or completing it with DM_ENDIO_REQUEUE can cause
unaligned write errors if the bio is a write operation targeting a
sequential zone. If a zoned target request such a requeue, warn about
it and kill the IO.

The function dm_is_zone_write() is introduced to detect write operations
to zoned targets.

This change does not affect the target drivers supporting zoned devices
and exposing a zoned device, namely dm-crypt, dm-linear and dm-flakey as
none of these targets ever request a requeue.

Signed-off-by: Damien Le Moal 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Himanshu Madhani 
Signed-off-by: Mike Snitzer

dm: move zone related code to dm-zone.c

2021-06-04T16:07:31+00:00

Move core and table code used for zoned targets and conditionally
defined with #ifdef CONFIG_BLK_DEV_ZONED to the new file dm-zone.c.
This file is conditionally compiled depending on CONFIG_BLK_DEV_ZONED.
The small helper dm_set_zones_restrictions() is introduced to
initialize a mapped device request queue zone attributes in
dm_table_set_restrictions().

Signed-off-by: Damien Le Moal 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Himanshu Madhani 
Signed-off-by: Mike Snitzer

dm: Fix dm_accept_partial_bio() relative to zone management commands

2021-06-04T16:07:29+00:00

Fix dm_accept_partial_bio() to actually check that zone management
commands are not passed as explained in the function documentation
comment. Also, since a zone append operation cannot be split, add
REQ_OP_ZONE_APPEND as a forbidden command.

White lines are added around the group of BUG_ON() calls to make the
code more legible.

Signed-off-by: Damien Le Moal 
Signed-off-by: Mike Snitzer

dm: convert to blk_alloc_disk/blk_cleanup_disk

2021-06-01T13:42:23+00:00

Convert the dm driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Ulf Hansson 
Link: https://lore.kernel.org/r/20210521055116.1053587-14-hch@lst.de
Signed-off-by: Jens Axboe

dm: unexport dm_{get,put}_table_device

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

These are only used by DM core, DM target modules should only use
dm_{get,put}_device.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Mike Snitzer