dm vdo delta-index: fix various small nits

Fix some needless line wrapping (given surrounding context), missing
braces and some stale or incorrect references to data structure or
function name.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo chapter_index: fix a few small nits

Add missing braces and raise one function arg up a line to eliminate
line wrap.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: cleanup style for comments in structs

Use /* ... */ rather than /** ... */ if for no other reason than
syntax highlighting is improved (at least for me, in emacs: comments
are now red, code is yellow. Previously comments were also yellow).

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo dedupe: fix various small nits

Add a __must_hold sparse annotation to launch_dedupe_state_change that
reflects its ASSERTION code comments about locking requirements, add
some extra braces and fix a couple typos.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo string-utils: remove unnecessary includes

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo message-stats: reformat to remove excessive newlines

Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: use #define for NO_CHAPTER and NO_CHAPTER_INDEX_ENTRY

Avoids unconventional use of 'static const' and enum in headers.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: move encoding constants to encodings.c

Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add documentation details on zones and locking

Add details describing the vdo zone and thread model to the
documentation comments for major vdo components. Also added
some high-level description of the block map structure.

Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add vio life cycle details to design doc

Add more documentation details for most aspects of the data_vio
read and write processes. Also correct a few minor errors and
rewrite some text for clarity.

Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add vdo documentation to device-mapper index

Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo recovery-journal: fix sparse 'mixed bitwiseness' warning

Only one user of WRITE_FLAGS so no need to factor it out in an enum
(which causes sparse's 'mixed bitwiseness' warning).  Just use the
flags in the only consumer.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo dedupe: silence sparse warnings about locking context imbalances

Annotate both open_index() and close_index() with
__must_hold(&zones->lock) to silence these sparse warnings:
 warning: context imbalance in 'close_index' - unexpected unlock
 warning: context imbalance in 'open_index' - unexpected unlock

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo data-vio: silence sparse warnings about locking context imbalances

Factor wait_permit() out from acquire_permit() so that the latter
always holds the spinlock and the former always releases it.

Otherwise sparse complains about locking context imbalances due to
conditional spin_unlock in acquire_permit:
 warning: context imbalance in 'acquire_permit' - different lock contexts for basic block
 warning: context imbalance in 'vdo_launch_bio' - unexpected unlock

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: fix various blk_opf_t sparse warnings

Use proper blk_opf_t type rather than unsigned int.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: fix sparse 'warning: Using plain integer as NULL pointer'

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: fix sparse warnings about missing statics

Addresses various sparse warnings like:
warning: symbol 'SYMBOL' was not declared. Should it be static?

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: rename struct configuration to uds_configuration

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: rename struct geometry to index_geometry

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo index: fix various small nits

Add braces around multi-line while loops and if statements. Also
remove excess newlines.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Chung Chung <cchung@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo dedupe: fix various small nits

Remove extra blank line, mark function inline, add missing
braces, and fix a typo in a comment.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Chung Chung <cchung@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo slab-depot: fix various small nits

Comment typo, whitespace issues, mark function inline.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Chung Chung <cchung@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo data-vio: rename is_trim flag to is_discard

Eliminate use of "trim" in favor of "discard" since it reflects the
top-level Linux discard primative rather than the ATA specific ditto.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: rename vdo_map_to_system_error to vdo_status_to_errno

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: rename uds_map_to_system_error to uds_status_to_errno

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: slight cleanup of UDS error codes

No need to increment each UDS_ error code manually (relative to
UDS_ERROR_CODE_BASE).

Also, remove unused PRP_BLOCK_START and PRP_BLOCK_END.

Lastly, UDS_SUCCESS and VDO_SUCCESS are used interchangeably; so best
to explicitly set VDO_SUCCESS equal to UDS_SUCCESS.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: rename struct cursors member to 'completion'

'completion' is more informative name for a 'struct vdo_completion'
than 'parent'.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: avoid extra dereferences to access vdo object

The vdo_page_cache's 'vdo' is the same as the block_map's vdo
instance, so use that to save 2 extra dereferences.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: remove extra vdo arg from initialize_block_map_zone

The block_map is passed to initialize_block_map_zone, but the
block_map's vdo member is already initialized with the same vdo
instance, so just use it.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: use uds_log_ratelimit() rather than open code it

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: fix a few small nits

Rename 'pages' to 'num_pages' in distribute_page_over_waitq().
Update assert message in validate_completed_page() to model others.
Tweak line-wrapping on a comment that was needlessly long.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: use a proper Makefile for dm-vdo

Requires moving dm-vdo-target.c into drivers/md/dm-vdo/

This change adds a proper drivers/md/dm-vdo/Makefile and eliminates
the abnormal use of patsubst in drivers/md/Makefile -- which was the
cause of at least one build failure that was reported by the upstream
build bot.

Also, split out VDO's drivers/md/dm-vdo/Kconfig and include it from
drivers/md/Kconfig

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: fix how dm_kcopyd_client_create() failure is checked

dm_kcopyd_client_create() returns an ERR_PTR so its return must be
checked with IS_ERR().

Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Chung Chung <cchung@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo int-map: remove unused parameter from vdo_int_map_create

Reviewed-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo int-map: rename functions to use a common vdo_int_map preamble

Reviewed-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo dedupe: switch to using int-map instead of pointer-map

Use get_unaligned_le64() on the hash lock's record name to serve as
the key to use with the int hash-map.

Switching to using int hash-map removes the only consumer of pointer
hash-map, as such it is removed.

Reviewed-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo wait-queue: rename to vdo_waitq_dequeue_waiter

Rename vdo_waitq_dequeue_next_waiter to vdo_waitq_dequeue_waiter.  The
"next" aspect of returned waiter is implied. "next" also isn't
informative ("oldest" would be). Removing "next_" adds symmetry to
vdo_waitq_enqueue_waiter().

Also fix whitespace and comments from previous waitq commit.

Reviewed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo block-map: optimize enter_zone_read_only_mode

Rather than incrementally dequeue from the zone->flush_waiters
vdo_wait_queue, simply re-initialize it.

Reviewed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo wait-queue: optimize vdo_waitq_dequeue_matching_waiters

Remove temporary 'matched_waiters' waitq and just enqueue matched
waiters directly to the caller provided 'matched_waitq'.

Reviewed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo wait-queue: remove unused debug function vdo_waitq_get_next_waiter

Reviewed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo wait-queue: add proper namespace to interface

Rename various interfaces and structs associated with vdo's wait-queue,
e.g.: s/wait_queue/vdo_wait_queue/, s/waiter/vdo_waiter/, etc.

Now all function names start with "vdo_waitq_" or "vdo_waiter_".

Reviewed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo io-submitter: rename to vdo_submit_vio and submit_data_vio

Rename process_vio_io() to vdo_submit_vio(), and process_data_vio_io() to
submit_data_vio().

Reviewed-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo io-submitter: rename to vdo_submit_data_vio

Rename submit_data_vio_io() to vdo_submit_data_vio().

Reviewed-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo io-submitter: rename to vdo_submit_flush_vio

Rename submit_flush_vio() to vdo_submit_flush_vio().

Reviewed-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo io-submitter: rename to vdo_submit_metadata_vio

Rename submit_metadata_vio() to vdo_submit_metadata_vio().

Reviewed-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo io-submitter: remove get_bio_sector

Just open-code access to bio's sector.

Reviewed-by: Susan LeGendre-McGhee <slegendr@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Matthew Sakai <msakai@redhat.com>

dm vdo: add MAINTAINERS file entry

Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: enable configuration and building of dm-vdo

dm-vdo targets are not supported for 32-bit configurations. A vdo target
typically requires 1 to 1.5 GB of memory at any given time, which is likely
a large fraction of the addressable memory of a 32-bit system. At the same
time, the amount of addressable storage attached to a 32-bit system may not
be large enough for deduplication to provide much benefit. Because of these
concerns, 32-bit platforms are deemed unlikely to benefit from using a vdo
target, so dm-vdo is targeted only at 64-bit platforms.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the top-level DM target

This adds the dm-vdo target.

The dm-vdo target provides inline deduplication, compression, and
zero-block elimination, allowing applications to consume less actual
storage than a normal target. By layering it with other device mapper
targets, it can add these features to any storage stack. It can also
provide a common deduplication pool for groups of targets. The vdo target
does not protect against data corruption, relying instead on integrity
protection of the storage below it.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add debugging support

Add support for dumping detailed vdo state to the kernel log via a dmsetup
message. The dump code is not thread-safe and is generally intended for use
only when the vdo is hung.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add sysfs support for setting parameters and fetching stats

Add data and methods setting run time parameters via sysfs, and to
make state and statistics information available through sysfs.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add statistics reporting

Add data and methods to report statisics.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the on-disk formats and marshalling of vdo structures

Add data and methods for marshalling and unmarshalling the persistent
metadata.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the primary vdo structure

Add the data and methods that manage the dm-vdo target itself. This
includes the overall state of the target and its threads, the state of
the logical volumes, startup, shutdown, and statistics.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add repair of damaged vdo volumes

When a vdo is restarted after a crash, it will automatically attempt to
recover from its journals.

If a vdo encounters an unrecoverable error, it will enter read-only mode.
This mode indicates that some previously acknowledged data may have been
lost. The vdo may be instructed to rebuild as best it can in order to
return to a writable state. Although some data may be lost, this process
will ensure that the vdo's own metadata is self-consistent.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the recovery journal

The recovery journal is used to amortize updates across the block map and
slab depot. Each write request causes an entry to be made in the journal.
Entries are either "data remappings" or "block map remappings." For a data
remapping, the journal records the logical address affected and its old and
new physical mappings. For a block map remapping, the journal records the
block map page number and the physical block allocated for it (block map
pages are never reclaimed, so the old mapping is always 0). Each journal
entry and the data write it represents must be stable on disk before the
other metadata structures may be updated to reflect the operation.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement the block map page cache

The set of leaf pages of the block map tree is too large to fit in memory,
so each block map zone maintains a cache of leaf pages. This patch adds the
implementation of that cache.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the block map

The block map contains the logical to physical mapping. It can be thought
of as an array with one entry per logical address. Each entry is 5 bytes:
36 bits contain the physical block number which holds the data for the
given logical address, and the remaining 4 bits are used to indicate the
nature of the mapping. Of the 16 possible states, one represents a logical
address which is unmapped (i.e. it has never been written, or has been
discarded), one represents an uncompressed block, and the other 14 states
are used to indicate that the mapped data is compressed, and which of the
compression slots in the compressed block this logical address maps to.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the slab depot

Add the data and methods that implement the slab_depot that manages
the allocation of slabs of blocks added by the preceding patches.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the block allocators and physical zones

Each slab is independent of every other. They are assigned to "physical
zones" in round-robin fashion. If there are P physical zones, then slab n
is assigned to zone n mod P. The set of slabs in each physical zone is
managed by a block allocator.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the slab summary

The slab depot maintains an additional small data structure, the "slab
summary," which is used to reduce the amount of work needed to come back
online after a crash. The slab summary maintains an entry for each slab
indicating whether or not the slab has ever been used, whether it is clean
(i.e. all of its reference count updates have been persisted to storage),
and approximately how full it is. During recovery, each physical zone will
attempt to recover at least one slab, stopping whenever it has recovered a
slab which has some free blocks. Once each zone has some space (or has
determined that none is available), the target can resume normal operation
in a degraded mode. Read and write requests can be serviced, perhaps with
degraded performance, while the remainder of the dirty slabs are recovered.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add slab structure, slab journal and reference counters

Most of the vdo volume belongs to the slab depot. The depot contains a
collection of slabs. The slabs can be up to 32GB, and are divided into
three sections. Most of a slab consists of a linear sequence of 4K blocks.
These blocks are used either to store data, or to hold portions of the
block map (see subsequent patches). In addition to the data blocks, each
slab has a set of reference counters, using 1 byte for each data block.
Finally each slab has a journal. Reference updates are written to the slab
journal, which is written out one block at a time as each block fills. A
copy of the reference counters is kept in memory, and are written out a
block at a time, in oldest-dirtied-order whenever there is a need to
reclaim slab journal space. The journal is used both to ensure that the
main recovery journal (see subsequent patches) can regularly free up space,
and also to amortize the cost of updating individual reference blocks.

This patch adds the slab structure as well as the slab journal and
reference counters.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the compressed block bin packer

When blocks do not deduplicate, vdo will attempt to compress them. Up to 14
compressed blocks may be packed into a single data block (this limitation
is imposed by the block map). The packer implements a simple best-fit
packing algorithm and also manages the formatting and writing of compressed
blocks when bins fill.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add use of deduplication index in hash zones

Add the data and methods that manage queries to the deduplication
index and the responses from the index.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add hash locks and hash zones

In order to deduplicate concurrent writes of the same data (to different
locations), data_vios which are writing the same data are grouped together
in a "hash lock," named for and keyed by the hash of the data being
written. Each hash lock is assigned to a hash zone based on a portion of
its hash.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the vdo io_submitter

The io_submitter handles bio submission from vdo data store to the storage
below. It will merge bios when possible.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add flush support

This patch adds support for handling incoming flush and/or FUA bios. Each
such bio is assigned to a struct vdo_flush. These are allocated as needed,
but there is always one kept in reserve in case allocations fail. In the
event of an allocation failure, bios may need to wait for an outstanding
flush to complete.

The logical address space is partitioned into logical zones, each handled
by its own thread. Each zone keeps a list of all data_vios handling write
requests for logical addresses in that zone. When a flush bio is processed,
each logical zone is informed of the flush. When all of the writes which
are in progress at the time of the notification have completed in all
zones, the flush bio is then allowed to complete.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add data_vio, the request object which services incoming bios

Add the data and methods that implement the data_vio object that
handles user data bios as they are processed.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add vio, the request object for vdo metadata

Add the data and methods that implement the vio object that is basic
unit of I/O in vdo.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add administrative state and action manager

This patch adds the admin_state structures which are used to track the
states of individual vdo components for handling of operations like suspend
and resume. It also adds the action manager which is used to schedule and
manage cross-thread administrative and internal operations.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement external deduplication index interface

The deduplication index interface for index clients includes the
deduplication request and index session structures. This is the interface
that the rest of the vdo target uses to make requests, receive responses,
and collect statistics.

This patch also adds sysfs nodes for inspecting various index properties at
runtime.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement top-level deduplication index

The top-level deduplication index brings all the earlier components
together. The top-level index creates the separate zone structures that
enable the index to handle several requests in parallel, handles
dispatching requests to the right zones and components, and coordinates
metadata to ensure that it remain consistent. It also coordinates recovery
in the event of an unexpected index failure.

If sparse caching is enabled, the top-level index also handles the
coordination required by the sparse chapter index cache, which (unlike most
index structures) is shared among all zones.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement the chapter volume store

The volume store structures manage the reading and writing of chapter
pages. When a chapter is closed, it is packed into a read-only structure,
split across several pages, and written to storage.

The volume store also contains a cache and specialized queues that sort and
batch requests by the page they need, in order to minimize latency and I/O
requests when records have to be read from storage. The cache and queues
also coordinate with the volume index to ensure that the volume does not
waste resources reading pages that are no longer valid.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement the open chapter and chapter indexes

Deduplication records are stored in groups called chapters. New records are
collected in a structure called the open chapter, which is optimized for
adding, removing, and sorting records.

When a chapter fills, it is packed into a read-only structure called a
closed chapter, which is optimized for searching and reading. The closed
chapter includes a delta index, called the chapter index, which maps each
record name to the record page containing the record and allows the index
to read at most one record page when looking up a record.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement the volume index

The volume index is a large delta index that maps each record name to the
chapter which contains the newest record for that name. The volume index
can contain several million records and is stored entirely in memory while
the index is operating, accounting for the majority of the deduplication
index's memory budget.

The volume index is composed of two subindexes in order to handle sparse
hook names separately from regular names. If sparse indexing is not
enabled, the sparse hook portion of the volume index is not used or
instantiated.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: implement the delta index

The delta index is a space and memory efficient alternative to a hashtable.
Instead of storing the entire key for each entry, the entries are sorted by
key and only the difference between adjacent keys (the delta) is stored.
If the keys are evenly distributed, the size of the deltas follows an
exponential distribution, and the deltas can use a Huffman code to take up
even less space.

This structure allows the index to use many fewer bytes per entry than a
traditional hash table, but it is slightly more expensive to look up
entries, because a request must read and sum every entry in a list of
deltas in order to find a given record. The delta index reduces this lookup
cost by splitting its key space into many sub-lists, each starting at a
fixed key value, so that each individual list is short.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add deduplication index storage interface

This patch adds infrastructure for managing reads and writes to the
underlying storage layer for the deduplication index. The deduplication
index uses dm-bufio for all of its reads and writes, so part of this
infrastructure is managing the various dm-bufio clients required. It also
adds the buffered reader and buffered writer abstractions, which simplify
reading and writing metadata structures that span several blocks.

This patch also includes structures and utilities for encoding and decoding
all of the deduplication index metadata, collectively called the index
layout.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add deduplication configuration structures

Add structures which record the configuration of various deduplication
index parameters. This also includes facilities for saving and loading the
configuration and validating its integrity.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add basic hash map data structures

This patch adds two hash maps, one keyed by integers, the other by
pointers, and also a priority heap. The integer map is used for locking of
logical and physical addresses. The pointer map is used for managing
concurrent writes of the same data, ensuring that those writes are
deduplicated. The priority heap is used to minimize the search time for
free blocks.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add specialized request queueing functionality

This patch adds funnel_queue, a mostly lock-free multi-producer,
single-consumer queue. It also adds the request queue used by the dm-vdo
deduplication index, and the work_queue used by the dm-vdo data store. Both
of these are built on top of funnel queue and are intended to support the
dispatching of many short-running tasks. The work_queue also supports
priorities. Finally, this patch adds vdo_completion, the structure which is
enqueued on work_queues.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add thread and synchronization utilities

This patch adds utilities for managing and using named threads, as well as
several locking and synchronization utilities. These utilities help dm-vdo
minimize thread transitions and manage interactions between threads.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: Bruce Johnston <bjohnsto@redhat.com>
Signed-off-by: Bruce Johnston <bjohnsto@redhat.com>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add vdo type declarations, constants, and simple data structures

Add definitions of constants defining the fixed parameters of a VDO
volume, and the default and maximum values of configurable or dynamic
parameters.

Add definitions of internal status codes used for internal
communication within the module and for logging.

Add definitions of types and structs used to manage the processing of
an I/O operation.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add basic logging and support utilities

Add various support utilities for the vdo target and deduplication index,
including logging utilities, string and time management, and index-specific
error codes.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add memory allocation utilities

This patch adds standardized allocation macros and memory tracking tools to
track and report any allocated memory that is not freed. This makes it
easier to ensure that the vdo target does not leak memory.

This patch also adds utilities for controlling whether certain threads are
allowed to allocate memory, since memory allocation during certain critical
code sections can cause the vdo target to deadlock.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Michael Sclafani <dm-devel@lists.linux.dev>
Signed-off-by: Michael Sclafani <dm-devel@lists.linux.dev>
Co-developed-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Signed-off-by: Thomas Jaskiewicz <tom@jaskiewicz.us>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm vdo: add the MurmurHash3 fast hashing algorithm

MurmurHash3 is a fast, non-cryptographic, 128-bit hash. It was originally
written by Austin Appleby and placed in the public domain. This version has
been modified to produce the same result on both big endian and little
endian processors, making it suitable for use in portable persistent data.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Co-developed-by: Ken Raeburn <raeburn@redhat.com>
Signed-off-by: Ken Raeburn <raeburn@redhat.com>
Co-developed-by: John Wiele <jwiele@redhat.com>
Signed-off-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: add documentation for dm-vdo target

This adds the admin-guide documentation for dm-vdo.

vdo.rst is the guide to using dm-vdo. vdo-design is an overview of the
design of dm-vdo.

Co-developed-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: J. corwin Coburn <corwin@hurlbutnet.net>
Signed-off-by: Matthew Sakai <msakai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

Linux 6.8-rc3

Merge tag 'for-linus-6.8-rc3' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Miscellaneous bug fixes and cleanups in ext4's multi-block allocator
  and extent handling code"

* tag 'for-linus-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
  ext4: make ext4_set_iomap() recognize IOMAP_DELALLOC map type
  ext4: make ext4_map_blocks() distinguish delalloc only extent
  ext4: add a hole extent entry in cache after punch
  ext4: correct the hole length returned by ext4_map_blocks()
  ext4: convert to exclusive lock while inserting delalloc extents
  ext4: refactor ext4_da_map_blocks()
  ext4: remove 'needed' in trace_ext4_discard_preallocations
  ext4: remove unnecessary parameter "needed" in ext4_discard_preallocations
  ext4: remove unused return value of ext4_mb_release_group_pa
  ext4: remove unused return value of ext4_mb_release_inode_pa
  ext4: remove unused return value of ext4_mb_release
  ext4: remove unused ext4_allocation_context::ac_groups_considered
  ext4: remove unneeded return value of ext4_mb_release_context
  ext4: remove unused parameter ngroup in ext4_mb_choose_next_group_*()
  ext4: remove unused return value of __mb_check_buddy
  ext4: mark the group block bitmap as corrupted before reporting an error
  ext4: avoid allocating blocks from corrupted group in ext4_mb_find_by_goal()
  ext4: avoid allocating blocks from corrupted group in ext4_mb_try_best_found()
  ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt
  ext4: avoid bb_free and bb_fragments inconsistency in mb_free_blocks()
  ...

Merge tag 'v6.8-rc3-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull smb client fixes from Steve French:
 "Five smb3 client fixes, mostly multichannel related:

   - four multichannel fixes including fix for channel allocation when
     multiple inactive channels, fix for unneeded race in channel
     deallocation, correct redundant channel scaling, and redundant
     multichannel disabling scenarios

   - add warning if max compound requests reached"

* tag 'v6.8-rc3-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: increase number of PDUs allowed in a compound request
  cifs: failure to add channel on iface should bump up weight
  cifs: do not search for channel if server is terminating
  cifs: avoid redundant calls to disable multichannel
  cifs: make sure that channel scaling is done only once

Merge tag 'xfs-6.8-fixes-2' of git://git./fs/xfs/xfs-linux

Pull xfs fixes from Chandan Babu:

 - Clear XFS_ATTR_INCOMPLETE filter on removing xattr from a node format
   attribute fork

 - Remove conditional compilation of realtime geometry validator
   functions to prevent confusing error messages from being printed on
   the console during the mount operation

* tag 'xfs-6.8-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: remove conditional building of rt geometry validator functions
  xfs: reset XFS_ATTR_INCOMPLETE filter on node removal

Merge tag 'char-misc-6.8-rc3' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc driver fixes from Greg KH:
 "Here are three tiny driver fixes for 6.8-rc3.  They include:

   - Android binder long-term bug with epoll finally being fixed

   - fastrpc driver shutdown bugfix

   - open-dice lockdep fix

  All of these have been in linux-next this week with no reported
  issues"

* tag 'char-misc-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  binder: signal epoll threads of self-work
  misc: open-dice: Fix spurious lockdep warning
  misc: fastrpc: Mark all sessions as invalid in cb_remove

Merge tag 'tty-6.8-rc3' of git://git./linux/kernel/git/gregkh/tty

Pull tty and serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 6.8-rc3 that
  resolve a number of reported issues. Included in here are:

   - rs485 flag definition fix that affected the user/kernel abi in -rc1

   - max310x driver fixes

   - 8250_pci1xxxx driver off-by-one fix

   - uart_tiocmget locking race fix

  All of these have been in linux-next for over a week with no reported
  issues"

* tag 'tty-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: max310x: prevent infinite while() loop in port startup
  serial: max310x: fail probe if clock crystal is unstable
  serial: max310x: improve crystal stable clock detection
  serial: max310x: set default value when reading clock ready bit
  serial: core: Fix atomicity violation in uart_tiocmget
  serial: 8250_pci1xxxx: fix off by one in pci1xxxx_process_read_data()
  tty: serial: Fix bit order in RS485 flag definitions

Merge tag 'usb-6.8-rc3' of git://git./linux/kernel/git/gregkh/usb

Pull USB driver fixes from Greg KH:
 "Here are a bunch of small USB driver fixes for 6.8-rc3. Included in
  here are:

   - new usb-serial driver ids

   - new dwc3 driver id added

   - typec driver change revert

   - ncm gadget driver endian bugfix

   - xhci bugfixes for a number of reported issues

   - usb hub bugfix for alternate settings

   - ulpi driver debugfs memory leak fix

   - chipidea driver bugfix

   - usb gadget driver fixes

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (24 commits)
  USB: serial: option: add Fibocom FM101-GL variant
  USB: serial: qcserial: add new usb-id for Dell Wireless DW5826e
  USB: serial: cp210x: add ID for IMST iM871A-USB
  usb: typec: tcpm: fix the PD disabled case
  usb: ucsi_acpi: Quirk to ack a connector change ack cmd
  usb: ucsi_acpi: Fix command completion handling
  usb: ucsi: Add missing ppm_lock
  usb: ulpi: Fix debugfs directory leak
  Revert "usb: typec: tcpm: fix cc role at port reset"
  usb: gadget: pch_udc: fix an Excess kernel-doc warning
  usb: f_mass_storage: forbid async queue when shutdown happen
  USB: hub: check for alternate port before enabling A_ALT_HNP_SUPPORT
  usb: chipidea: core: handle power lost in workqueue
  usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend
  usb: dwc3: pci: add support for the Intel Arrow Lake-H
  usb: core: Prevent null pointer dereference in update_port_device_state
  xhci: handle isoc Babble and Buffer Overrun events properly
  xhci: process isoc TD properly when there was a transaction error mid TD.
  xhci: fix off by one check when adding a secondary interrupter.
  xhci: fix possible null pointer dereference at secondary interrupter removal
  ...

Merge tag 'i2c-for-6.8-rc3' of git://git./linux/kernel/git/wsa/linux

Pull i2c fixlet from Wolfram Sang:
 "MAINTAINERS update to point people to the new tree for i2c host driver
  changes"

* tag 'i2c-for-6.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  MAINTAINERS: Update i2c host drivers repository

Merge tag 'dmaengine-fix-6.8' of git://git./linux/kernel/git/vkoul/dmaengine

Pull dmaengine fixes from Vinod Koul:
 "Core:

   - fix return value of is_slave_direction() for D2D dma

  Driver fixes for:

   - Documentaion fixes to resolve warnings for at_hdmac driver

   - bunch of fsl driver fixes for memory leaks, and useless kfree

   - TI edma and k3 fixes for packet error and null pointer checks"

* tag 'dmaengine-fix-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
  dmaengine: at_hdmac: add missing kernel-doc style description
  dmaengine: fix is_slave_direction() return false when DMA_DEV_TO_DEV
  dmaengine: fsl-qdma: Remove a useless devm_kfree()
  dmaengine: fsl-qdma: Fix a memory leak related to the queue command DMA
  dmaengine: fsl-qdma: Fix a memory leak related to the status queue DMA
  dmaengine: ti: k3-udma: Report short packet errors
  dmaengine: ti: edma: Add some null pointer checks to the edma_probe
  dmaengine: fsl-dpaa2-qdma: Fix the size of dma pools
  dmaengine: at_hdmac: fix some kernel-doc warnings

Merge tag 'phy-fixes-6.8' of git://git./linux/kernel/git/phy/linux-phy

Pull phy driver fixes from Vinod Koul:

 - TI null pointer dereference

 - missing erdes mux entry in lan966x driver

 - Return of error code in renesas driver

 - Serdes init sequence and register offsets for IPQ drivers

* tag 'phy-fixes-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/phy/linux-phy:
  phy: ti: phy-omap-usb2: Fix NULL pointer dereference for SRP
  phy: lan966x: Add missing serdes mux entry
  phy: renesas: rcar-gen3-usb2: Fix returning wrong error code
  phy: qcom-qmp-usb: fix serdes init sequence for IPQ6018
  phy: qcom-qmp-usb: fix register offsets for ipq8074/ipq6018

Merge tag 'i2c-host-fixes-6.8-rc3' of git://git./linux/kernel/git/andi.shyti/linux into i2c/for-current

Just a maintenance patch that updates the repository where the
i2c host and muxes related patches will be collected.

Merge tag 'perf-tools-fixes-for-v6.8-1-2024-02-01' of git://git./linux/kernel/git/perf/perf-tools

Pull perf tools fixes from Arnaldo Carvalho de Melo:
 "Vendor events:

   - Intel Alderlake/Sapphire Rapids metric fixes, the CPU type
     ("cpu_atom", "cpu_core") needs to be used as a prefix to be
     considered on a metric formula, detected via one of the 'perf test'
     entries.

  'perf test' fixes:

   - Fix the creation of event selector lists on 'perf test' entries, by
     initializing the sample ID flag, which is done by 'perf record', so
     this fix affects only the tests, the common case isn't affected

   - Make 'perf list' respect debug settings (-v) to fix its 'perf test'
     entry

   - Fix 'perf script' test when python support isn't enabled

   - Special case 'perf script' tests on s390, where only DWARF call
     graphs are supported and only on software events

   - Make 'perf daemon' signal test less racy

  Compiler warnings/errors:

   - Remove needless malloc(0) call in 'perf top' that triggers
     -Walloc-size

   - Fix calloc() argument order to address error introduced in gcc-14

  Build:

   - Make minimal shellcheck version to v0.6.0, avoiding the build to
     fail with older versions

  Sync kernel header copies:

   - stat.h to pick STATX_MNT_ID_UNIQUE

   - msr-index.h to pick IA32_MKTME_KEYID_PARTITIONING

   - drm.h to pick DRM_IOCTL_MODE_CLOSEFB

   - unistd.h to pick {list,stat}mount,
     lsm_{[gs]et_self_attr,list_modules} syscall numbers

   - x86 cpufeatures to pick TDX, Zen, APIC MSR fence changes

   - x86's mem{cpy,set}_64.S used in 'perf bench'

   - Also, without tooling effects: asm-generic/unaligned.h, mount.h,
     fcntl.h, kvm headers"

* tag 'perf-tools-fixes-for-v6.8-1-2024-02-01' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (21 commits)
  perf tools headers: update the asm-generic/unaligned.h copy with the kernel sources
  tools include UAPI: Sync linux/mount.h copy with the kernel sources
  perf evlist: Fix evlist__new_default() for > 1 core PMU
  tools headers: Update the copy of x86's mem{cpy,set}_64.S used in 'perf bench'
  tools headers x86 cpufeatures: Sync with the kernel sources to pick TDX, Zen, APIC MSR fence changes
  tools headers UAPI: Sync unistd.h to pick {list,stat}mount, lsm_{[gs]et_self_attr,list_modules} syscall numbers
  perf vendor events intel: Alderlake/sapphirerapids metric fixes
  tools headers UAPI: Sync kvm headers with the kernel sources
  perf tools: Fix calloc() arguments to address error introduced in gcc-14
  perf top: Remove needless malloc(0) call that triggers -Walloc-size
  perf build: Make minimal shellcheck version to v0.6.0
  tools headers UAPI: Update tools's copy of drm.h headers to pick DRM_IOCTL_MODE_CLOSEFB
  perf test shell daemon: Make signal test less racy
  perf test shell script: Fix test for python being disabled
  perf test: Workaround debug output in list test
  perf list: Add output file option
  perf list: Switch error message to pr_err() to respect debug settings (-v)
  perf test: Fix 'perf script' tests on s390
  tools headers UAPI: Sync linux/fcntl.h with the kernel sources
  tools arch x86: Sync the msr-index.h copy with the kernel sources to pick IA32_MKTME_KEYID_PARTITIONING
  ...

Merge tag 'trace-v6.8-rc2' of git://git./linux/kernel/git/trace/linux-trace

Pull tracing and eventfs fixes from Steven Rostedt:

 - Fix the return code for ring_buffer_poll_wait()

   It was returing a -EINVAL instead of EPOLLERR.

 - Zero out the tracefs_inode so that all fields are initialized.

   The ti->private could have had stale data, but instead of just
   initializing it to NULL, clear out the entire structure when it is
   allocated.

 - Fix a crash in timerlat

   The hrtimer was initialized at read and not open, but is canceled at
   close. If the file was opened and never read the close will pass a
   NULL pointer to hrtime_cancel().

 - Rewrite of eventfs.

   Linus wrote a patch series to remove the dentry references in the
   eventfs_inode and to use ref counting and more of proper VFS
   interfaces to make it work.

 - Add warning to put_ei() if ei is not set to free. That means
   something is about to free it when it shouldn't.

 - Restructure the eventfs_inode to make it more compact, and remove the
   unused llist field.

 - Remove the fsnotify*() funtions for when the inodes were being
   created in the lookup code. It doesn't make sense to notify about
   creation just because something is being looked up.

 - The inode hard link count was not accurate.

   It was being updated when a file was looked up. The inodes of
   directories were updating their parent inode hard link count every
   time the inode was created. That means if memory reclaim cleaned a
   stale directory inode and the inode was lookup up again, it would
   increment the parent inode again as well. Al Viro said to just have
   all eventfs directories have a hard link count of 1. That tells user
   space not to trust it.

* tag 'trace-v6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Keep all directory links at 1
  eventfs: Remove fsnotify*() functions from lookup()
  eventfs: Restructure eventfs_inode structure to be more condensed
  eventfs: Warn if an eventfs_inode is freed without is_freed being set
  tracing/timerlat: Move hrtimer_init to timerlat_fd open()
  eventfs: Get rid of dentry pointers without refcounts
  eventfs: Clean up dentry ops and add revalidate function
  eventfs: Remove unused d_parent pointer field
  tracefs: dentry lookup crapectomy
  tracefs: Avoid using the ei->dentry pointer unnecessarily
  eventfs: Initialize the tracefs inode properly
  tracefs: Zero out the tracefs_inode when allocating it
  ring-buffer: Clean ring_buffer_poll_wait() error return

Merge tag 'gfs2-v6.8-rc2-revert' of git://git./linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 revert from Andreas Gruenbacher:
 "It turns out that the commit to use GL_NOBLOCK flag for non-blocking
  lookups has several issues, and not all of them have a simple fix"

* tag 'gfs2-v6.8-rc2-revert' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  Revert "gfs2: Use GL_NOBLOCK flag for non-blocking lookups"