Introduce the zoned_loop.rst documentation file under
admin-guide/blockdev to document the zoned loop block device driver.
An overview of the driver is provided and its usage to create and delete
zoned devices described.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250407075222.170336-3-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The zoned loop block device driver allows a user to create emulated
zoned block devices using one regular file per zone as backing storage.
Compared to null_blk or scsi_debug, it has the advantage of allowing
emulating large zoned devices without requiring the same amount of
memory as the capacity of the emulated device. Furthermore, zoned
devices emulated with this driver can be re-started after a host reboot
without any loss of the state of the device zones, which is something
that null_blk and scsi_debug do not support.

This initial implementation is simple and does not support zone resource
limits. That is, a zoned loop block device limits for the maximum number
of open zones and maximum number of active zones is always 0.

This driver can be either compiled in-kernel or as a module, named
"zloop". Compilation of this driver depends on the block layer support
for zoned block device (CONFIG_BLK_DEV_ZONED must be set).

Using the zloop driver to create and delete zoned block devices is
done by writing commands to the zoned loop control character device file
(/dev/zloop-control). Creating a device is done with:

  $ echo "add [options]" > /dev/zloop-control

The options available for the "add" operation cat be listed by reading
the zloop-control device file:

  $ cat /dev/zloop-control
  add id=%d,capacity_mb=%u,zone_size_mb=%u,zone_capacity_mb=%u,conv_zones=%u,base_dir=%s,nr_queues=%u,queue_depth=%u
  remove id=%d

The options available allow controlling the zoned device total
capacity, zone size, zone capactity of sequential zones, total number
of conventional zones, base directory for the zones backing file, number
of I/O queues and the maximum queue depth of I/O queues.

Deleting a device is done using the "remove" command:

  $ echo "remove id=0" > /dev/zloop-control

This implementation passes various tests using zonefs and fio (t/zbd
tests) and provides a state machine for zone conditions that is
compliant with the T10 ZBC and NVMe ZNS specifications.

Co-developed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20250407075222.170336-2-dlemoal@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull block fixes from Jens Axboe:

 - MD pull via Yu:
      - fix raid10 missing discard IO accounting (Yu Kuai)
      - fix bitmap stats for bitmap file (Zheng Qixing)
      - fix oops while reading all member disks failed during
        check/repair (Meir Elisha)

 - NVMe pull via Christoph:
      - fix scan failure for non-ANA multipath controllers (Hannes
        Reinecke)
      - fix multipath sysfs links creation for some cases (Hannes
        Reinecke)
      - PCIe endpoint fixes (Damien Le Moal)
      - use NULL instead of 0 in the auth code (Damien Le Moal)

 - Various ublk fixes:
      - Slew of selftest additions
      - Improvements and fixes for IO cancelation
      - Tweak to Kconfig verbiage

 - Fix for page dirtying for blk integrity mapped pages

 - loop fixes:
      - buffered IO fix
      - uevent fixes
      - request priority inheritance fix

 - Various little fixes

* tag 'block-6.15-20250417' of git://git.kernel.dk/linux: (38 commits)
  selftests: ublk: add generic_06 for covering fault inject
  ublk: simplify aborting ublk request
  ublk: remove __ublk_quiesce_dev()
  ublk: improve detection and handling of ublk server exit
  ublk: move device reset into ublk_ch_release()
  ublk: rely on ->canceling for dealing with ublk_nosrv_dev_should_queue_io
  ublk: add ublk_force_abort_dev()
  ublk: properly serialize all FETCH_REQs
  selftests: ublk: move creating UBLK_TMP into _prep_test()
  selftests: ublk: add test_stress_05.sh
  selftests: ublk: support user recovery
  selftests: ublk: support target specific command line
  selftests: ublk: increase max nr_queues and queue depth
  selftests: ublk: set queue pthread's cpu affinity
  selftests: ublk: setup ring with IORING_SETUP_SINGLE_ISSUER/IORING_SETUP_DEFER_TASKRUN
  selftests: ublk: add two stress tests for zero copy feature
  selftests: ublk: run stress tests in parallel
  selftests: ublk: make sure _add_ublk_dev can return in sub-shell
  selftests: ublk: cleanup backfile automatically
  selftests: ublk: add io_uring uapi header
  ...

The CONFIG_BLK_DEV_UBLK help text suggests setting the config option to
Y so task_work_add() can be used to dispatch I/O, improving performance.
However, this mechanism was removed in commit 29dc5d06613f2 ("ublk: kill
queuing request by task_work_add"). So remove this paragraph from the
config help text.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Uday Shankar <ushankar@purestorage.com>
Link: https://lore.kernel.org/r/20250416004111.3242817-1-csander@purestorage.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Now that LIBCRC32C does nothing besides select CRC32, make every option
that selects LIBCRC32C instead select CRC32 directly.  Then remove
LIBCRC32C.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20250401221600.24878-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

Deprecation period of reiserfs ends with the end of this year so it is
time to remove it from the kernel.

Acked-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>

This patch adds an initial version of the Rust null block driver.

Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240611114551.228679-3-nmi@metaspace.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>

All ublk commands(control, IO) should have taken ioctl command encoding
from the beginning, because ioctl command encoding defines each code
uniquely, so driver can figure out wrong command sent from userspace
easily; 2) it might help security subsystem for audit uring cmd[1].

Unfortunately we didn't do that way, and it could be one lesson for
ublk driver.

So switch to ioctl command encoding now, we still support commands encoded
in old way, but they become legacy definition. Any new command should take
ioctl encoding.

See ublksrv code for switching to ioctl command encoding in [2].

[1] https://lore.kernel.org/io-uring/CAHC9VhSVzujW9LOj5Km80AjU0EfAuukoLrxO6BEfnXeK_s6bAg@mail.gmail.com/
[2] https://github.com/ming1/ubdsrv/commits/ioctl_cmd_encoding

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ken Kurematsu <k.kurematsu@nskint.co.jp>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230418131810.855959-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull ATA updates from Damien Le Moal:

 - Small cleanup of the pata_octeon driver to drop a useless platform
   callback (Uwe)

 - Simplify ata_scsi_cmd_error_handler() code using the fact that
   ap->ops->error_handler is NULL most of the time (Wenchao)

 - Several patches improving libata error handling. This is in
   preparation for supporting the command duration limits (CDL) feature.
   The changes allow handling corner cases of ATA NCQ errors which do
   not happen with regular drives but will be triggered with CDL drives
   (Niklas)

 - Simplify the qc_fill_rtf operation (me)

 - Improve SCSI command translation for REPORT_SUPPORTED_OPERATION_CODES
   command (me)

 - Cleanup of libata FUA handling.

   This falls short of enabling FUA for ATA drives that support it by
   default as there were concerns that old drives would break. The
   series however fixes several issues with the FUA support to ensure
   that FUA is reported as being supported only for drives that can
   handle all possible write cases (NCQ and non-NCQ). A check in the
   block layer is also added to ensure that we never see read FUA
   commands (current behavior) (me)

 - Several patches to move the old PARIDE (parallel port IDE) driver to
   libata as pata_parport. Given that this driver also needs protocol
   modules, the driver code resides in its own pata_parport directoy
   under drivers/ata (Ondrej)

* tag 'ata-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
  ata: pata_parport: Fix ida_alloc return value error check
  drivers/block: Move PARIDE protocol modules to drivers/ata/pata_parport
  drivers/block: Remove PARIDE core and high-level protocols
  ata: pata_parport: add driver (PARIDE replacement)
  ata: libata: exclude FUA support for known buggy drives
  ata: libata: Fix FUA handling in ata_build_rw_tf()
  ata: libata: cleanup fua support detection
  ata: libata: Rename and cleanup ata_rwcmd_protocol()
  ata: libata: Introduce ata_ncq_supported()
  block: add a sanity check for non-write flush/fua bios
  ata: libata-scsi: improve ata_scsiop_maint_in()
  ata: libata-scsi: do not overwrite SCSI ML and status bytes
  ata: libata: move NCQ related ATA_DFLAGs
  ata: libata: respect successfully completed commands during errors
  ata: libata: read the shared status for successful NCQ commands once
  ata: libata: simplify qc_fill_rtf port operation interface
  ata: scsi: rename flag ATA_QCFLAG_FAILED to ATA_QCFLAG_EH
  ata: libata-eh: Cleanup ata_scsi_cmd_error_handler()
  ata: octeon: Drop empty platform remove function

Move PARIDE protocol modules out of drivers/block into
drivers/ata/pata_parport and update the CONFIG_ symbol names to
PATA_PARPORT.

[Damien]
The pata_parport driver file itsef is also moved together with the
protocol modules in drivers/ata/pata_parport.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>