Support stacking atomic write limits for DM devices.

All the pre-existing code in blk_stack_atomic_writes_limits() already takes
care of finding the aggregrate limits from the bottom devices.

Feature flag DM_TARGET_ATOMIC_WRITES is introduced so that atomic writes
can be enabled on personalities selectively. This is to ensure that atomic
writes are only enabled when verified to be working properly (for a
specific personality). In addition, it just may not make sense to enable
atomic writes on some personalities (so this flag also helps there).

Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

dm_table_bio_based() is unused since commit
29dec90a0f1d ("dm: fix bio_set allocation")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

This commit introduces the dm target flag mempool_needs_integrity. When
the flag is set, device mapper will call bioset_integrity_create on it's
bio sets. The target can then call bio_integrity_alloc on the bios
allocated from the table's mempool.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

Factor out a helper function, dm_devt_from_path(), from dm_get_device()
for use in dm targets.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

Device mapper sends flush bios to all the targets and the targets send it
to the underlying device. That may be inefficient, for example if a table
contains 10 linear targets pointing to the same physical device, then
device mapper would send 10 flush bios to that device - despite the fact
that only one bio would be sufficient.

This commit optimizes the flush behavior. It introduces a per-target
variable flush_bypasses_map - it is set when the target supports flush
optimization - currently, the dm-linear and dm-stripe targets support it.
When all the targets in a table have flush_bypasses_map,
flush_bypasses_map on the table is set. __send_empty_flush tests if the
table has flush_bypasses_map - and if it has, no flush bios are sent to
the targets via the "map" method and the list dm_table->devices is
iterated and the flush bios are sent to each member of the list.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Suggested-by: Yang Yang <yang.yang@vivo.com>

Merge in queue limits cleanups.

* for-6.11/block-limits:
  block: move the raid_partial_stripes_expensive flag into the features field
  block: remove the discard_alignment flag
  block: move the misaligned flag into the features field
  block: renumber and rename the cache disabled flag
  block: fix spelling and grammar for in writeback_cache_control.rst
  block: remove the unused blk_bounce enum

queue_limits.discard_alignment is never read except in the places
where it is stacked into another limit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20240619154623.450048-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Merge in last round of queue limits changes from Christoph.

* for-6.11/block-limits: (26 commits)
  block: move the bounce flag into the features field
  block: move the skip_tagset_quiesce flag to queue_limits
  block: move the pci_p2pdma flag to queue_limits
  block: move the zone_resetall flag to queue_limits
  block: move the zoned flag into the features field
  block: move the poll flag to queue_limits
  block: move the dax flag to queue_limits
  block: move the nowait flag to queue_limits
  block: move the synchronous flag to queue_limits
  block: move the stable_writes flag to queue_limits
  block: move the io_stat flag setting to queue_limits
  block: move the add_random flag to queue_limits
  block: move the nonrot flag to queue_limits
  block: move cache control settings out of queue->flags
  block: remove blk_flush_policy
  block: freeze the queue in queue_attr_store
  nbd: move setting the cache control flags to __nbd_set_size
  virtio_blk: remove virtblk_update_cache_mode
  loop: fold loop_update_rotational into loop_reconfigure_limits
  loop: also use the default block size from an underlying block device
  ...

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Move the zoned flags into the features field to reclaim a little
bit of space.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-23-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Move the poll flag into the queue_limits feature field so that it can
be set atomically with the queue frozen.

Stacking drivers are simplified in that they now can simply set the
flag, and blk_stack_limits will clear it when the features is not
supported by any of the underlying devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-22-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>