After commit 35fe6d76 ("block: use standard blktrace API to output
cgroup info for debug notes"), the field 'bfqg->blkg_path' is not used
and hence can be removed, and therefor blkg_path() is not used anymore
and can be removed.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240618032753.3502528-1-yukuai1@huaweicloud.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Remove a superfluous argument that flag_show and flag_store currently
take.
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240617044918.374608-1-joshi.k@samsung.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Currently building for C=1 generates the following warning:
block/bfq-iosched.c:5498:9: warning: context imbalance in 'bfq_exit_icq' - different lock contexts for basic block

Refactor bfq_exit_icq() into a core part which loops for the actuators,
and only lock calling this routine when necessary.
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240614090345.655716-4-john.g.garry@oracle.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Currently compiling block/blk-settings.c with C=1 gives the following
warning:
block/blk-settings.c:262:9: warning: context imbalance in 'queue_limits_commit_update' - wrong count at exit

request_queue.limits_lock is a mutex. Sparse locking annotation for
mutexes are currently not supported - see [0] - so drop that locking
annotation.

[0] https://lore.kernel.org/lkml/cover.1579893447.git.jbi.octave@gmail.com/T/#mbb8bda6c0a7ca7ce19f46df976a8e3b489745488

Fixes: d690cb8a ("block: add an API to atomically update queue limits")
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240614090345.655716-3-john.g.garry@oracle.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

The blockdev_mnt are not used outside the file bdev.c, so the modification
is defined as static.

block/bdev.c:377:17: warning: symbol 'blockdev_mnt' was not declared. Should it be static?
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
jpg: Remove closes bugzilla link
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Fixes: 8f3a608827d1 ("bdev: open block device as files")
Tested-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240614090345.655716-2-john.g.garry@oracle.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

With the switch to using the zone append emulation of the block layer
zone write plugging, the macro DM_ZONE_INVALID_WP_OFST is no longer used
in dm-zone.c. Remove its definition.

Fixes: f211268e ("dm: Use the block layer zone append emulation")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20240611023639.89277-5-dlemoal@kernel.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

The generic stacking of limits implemented in the block layer cannot
correctly handle stacking of zone resource limits (max open zones and
max active zones) because these limits are for an entire device but the
stacking may be for a portion of that device (e.g. a dm-linear target
that does not cover an entire block device). As a result, when DM
devices are created on top of zoned block devices, the DM device never
has any zone resource limits advertized, which is only correct if all
underlying target devices also have no zone resource limits.
If at least one target device has resource limits, the user may see
either performance issues (if the max open zone limit of the device is
exceeded) or write I/O errors if the max active zone limit of one of
the underlying target devices is exceeded.

While it is very difficult to correctly and reliably stack zone resource
limits in general, cases where targets are not sharing zone resources of
the same device can be dealt with relatively easily. Such situation
happens when a target maps all sequential zones of a zoned block device:
for such mapping, other targets mapping other parts of the same zoned
block device can only contain conventional zones and thus will not
require any zone resource to correctly handle write operations.

For a mapped device constructed with such targets, which includes mapped
devices constructed with targets mapping entire zoned block devices, the
zone resource limits can be reliably determined using the non-zero
minimum of the zone resource limits of all targets.

For mapped devices that include targets partially mapping the set of
sequential write required zones of zoned block devices, instead of
advertizing no zone resource limits, it is also better to set the mapped
device limits to the non-zero minimum of the limits of all targets. In
this case the limits for a target depend on the number of sequential
zones being mapped: if this number of zone is larger than the limits,
then the limits of the device apply and can be used. If on the other
hand the target maps a number of zones smaller than the limits, then no
limits is needed and we can assume that the target has no limits (limits
set to 0).

This commit improves zone resource limits handling as described above
by modifying dm_set_zones_restrictions() to iterate the targets of a
mapped device to evaluate the max open and max active zone limits. This
relies on an internal "stacking" of the limits of the target devices
combined with a direct counting of the number of sequential zones
mapped by the targets.
1) For a target mapping an entire zoned block device, the limits for the
   target are set to the limits of the device.
2) For a target partially mapping a zoned block device, the number of
   mapped sequential zones is used to determine the limits: if the
   target maps more sequential write required zones than the device
   limits, then the limits of the device are used as-is. If the number
   of mapped sequential zones is lower than the limits, then we assume
   that the target has no limits (limits set to 0).
As this evaluation is done for each target, the zone resource limits
for the mapped device are evaluated as the non-zero minimum of the
limits of all the targets.

For configurations resulting in unreliable limits, i.e. a table
containing a target partially mapping a zoned device, a warning message
is issued.

The counting of mapped sequential zones for the target is done using the
new function dm_device_count_zones() which performs a report zones on
the entire block device with the callback dm_device_count_zones_cb().
This count of mapped sequential zones is also used to determine if the
mapped device contains only conventional zones. This allows simplifying
dm_set_zones_restrictions() to not do a report zones just for this.
For mapped devices mapping only conventional zones, as before, the
mapped device is changed to a regular device by setting its zoned limit
to false and clearing all its zone related limits.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20240611023639.89277-4-dlemoal@kernel.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

dm_revalidate_zones() is called from dm_set_zone_restrictions() when the
mapped device queue limits are not yet set. However,
dm_revalidate_zones() calls blk_revalidate_disk_zones() and this
function consults and modifies the mapped device queue limits. Thus,
currently, blk_revalidate_disk_zones() operates on limits that are not
yet initialized.

Fix this by moving the call to dm_revalidate_zones() out of
dm_set_zone_restrictions() and into dm_table_set_restrictions() after
executing queue_limits_set().

To further cleanup dm_set_zones_restrictions(), the message about the
type of zone append (native or emulated) is also moved inside
dm_revalidate_zones().

Fixes: 1c0e7202 ("dm: use queue_limits_set")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Link: https://lore.kernel.org/r/20240611023639.89277-3-dlemoal@kernel.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

Make sure that the zone resource limits of a zoned block device are
correct by checking that:
(a) If the device has a max active zones limit, make sure that the max
    open zones limit is lower than the max active zones limit.
(b) If the device has zone resource limits, check that the limits
    values are lower than the number of sequential zones of the device.
    If it is not, assume that the zoned device has no limits by setting
    the limits to 0.

For (a), a check is added to blk_validate_zoned_limits() and an error
returned if the max open zones limit exceeds the value of the max active
zone limit (if there is one).

For (b), given that we need the number of sequential zones of the zoned
device, this check is added to disk_update_zone_resources(). This is
safe to do as that function is executed with the disk queue frozen and
the check executed after queue_limits_start_update() which takes the
queue limits lock. Of note is that the early return in this function
for zoned devices that do not use zone write plugging (e.g. DM devices
using native zone append) is moved to after the new check and adjustment
of the zone resource limits so that the check applies to any zoned
device.
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
Link: https://lore.kernel.org/r/20240611023639.89277-2-dlemoal@kernel.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

The Rust block layer API was using the old queue limit API, which was just
removed. Use the new API instead.
Reported-by: Boqun Feng <boqun.feng@gmail.com>
Fixes: 3253aba3 ("rust: block: introduce `kernel::block::mq` module")
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Link: https://lore.kernel.org/r/20240614235350.621121-1-nmi@metaspace.dkSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pull in block limits branch, which exists as a shared branch for both
the block and SCSI tree.

* for-6.11/block-limits: (26 commits)
  block: move integrity information into queue_limits
  block: invert the BLK_INTEGRITY_{GENERATE,VERIFY} flags
  block: bypass the STABLE_WRITES flag for protection information
  block: don't require stable pages for non-PI metadata
  block: use kstrtoul in flag_store
  block: factor out flag_{store,show} helper for integrity
  block: remove the blk_flush_integrity call in blk_integrity_unregister
  block: remove the blk_integrity_profile structure
  dm-integrity: use the nop integrity profile
  md/raid1: don't free conf on raid0_run failure
  md/raid0: don't free conf on raid0_run failure
  block: initialize integrity buffer to zero before writing it to media
  block: add special APIs for run-time disabling of discard and friends
  block: remove unused queue limits API
  sr: convert to the atomic queue limits API
  sd: convert to the atomic queue limits API
  sd: cleanup zoned queue limits initialization
  sd: factor out a sd_discard_mode helper
  sd: simplify the disable case in sd_config_discard
  sd: add a sd_disable_write_same helper
  ...

Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.

Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired.  However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED().  Given that tiny size of it that seems like
a worthwhile trade off.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Invert the flags so that user set values will be able to persist
revalidating the integrity information once we switch the integrity
information to queue_limits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-12-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Currently registering a checksum-enabled (aka PI) integrity profile sets
the QUEUE_FLAG_STABLE_WRITE flag, and unregistering it clears the flag.
This can incorrectly clear the flag when the driver requires stable
writes even without PI, e.g. in case of iSCSI or NVMe/TCP with data
digest enabled.

Fix this by looking at the csum_type directly in bdev_stable_writes and
not setting the queue flag.  Also remove the blk_queue_stable_writes
helper as the only user in nvme wants to only look at the actual
QUEUE_FLAG_STABLE_WRITE flag as it inherits the integrity configuration
by other means.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240613084839.1044015-11-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Non-PI metadata doesn't contain checksums and thus doesn't require
stable pages.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240613084839.1044015-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the text to integer helper that has error handling and doesn't modify
the input pointer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-9-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Factor the duplicate code for the generate and verify attributes into
common helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240613084839.1044015-8-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Now that there are no indirect calls for PI processing there is no
way to dereference a NULL pointer here.  Additionally drivers now always
freeze the queue (or in case of stacking drivers use their internal
equivalent) around changing the integrity profile.

This is effectively a revert of commit 3df49967 ("block: flush the
integrity workqueue in blk_integrity_unregister").
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240613084839.1044015-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Block layer integrity configuration is a bit complex right now, as it
indirects through operation vectors for a simple two-dimensional
configuration:

 a) the checksum type of none, ip checksum, crc, crc64
 b) the presence or absence of a reference tag

Remove the integrity profile, and instead add a separate csum_type flag
which replaces the existing ip-checksum field and a new flag that
indicates the presence of the reference tag.

This removes up to two layers of indirect calls, remove the need to
offload the no-op verification of non-PI metadata to a workqueue and
generally simplifies the code. The downside is that block/t10-pi.c now
has to be built into the kernel when CONFIG_BLK_DEV_INTEGRITY is
supported.  Given that both nvme and SCSI require t10-pi.ko, it is loaded
for all usual configurations that enabled CONFIG_BLK_DEV_INTEGRITY
already, though.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-6-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the block layer built-in nop profile instead of duplicating it.

Tested by:

$ dd if=/dev/urandom of=key.bin bs=512 count=1

$ cryptsetup luksFormat -q --type luks2 --integrity hmac-sha256 \
 	--integrity-no-wipe /dev/nvme0n1 key.bin
$ cryptsetup luksOpen /dev/nvme0n1 luks-integrity --key-file key.bin

and then doing mkfs.xfs and simple I/O on the mount file system.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Milan Broz <gmazyland@gmail.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-5-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

The core md code calls the ->free method which already frees conf.

Fixes: 07f1a685 ("md/raid1: fail run raid1 array when active disk less than one")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-4-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

The core md code calls the ->free method which already frees conf.

Fixes: 0c031fd3 ("md: Move alloc/free acct bioset in to personality")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Metadata added by bio_integrity_prep is using plain kmalloc, which leads
to random kernel memory being written media.  For PI metadata this is
limited to the app tag that isn't used by kernel generated metadata,
but for non-PI metadata the entire buffer leaks kernel memory.

Fix this by adding the __GFP_ZERO flag to allocations for writes.

Fixes: 7ba1ba12 ("block: Block layer data integrity support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

A few drivers optimistically try to support discard, write zeroes and
secure erase and disable the features from the I/O completion handler
if the hardware can't support them.  This disable can't be done using
the atomic queue limits API because the I/O completion handlers can't
take sleeping locks or freeze the queue.  Keep the existing clearing
of the relevant field to zero, but replace the old blk_queue_max_*
APIs with new disable APIs that force the value to 0.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-15-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Remove all APIs that are unused now that sd and sr have been converted
to the atomic queue limits API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-14-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Assign all queue limits through a local queue_limits variable and
queue_limits_commit_update so that we can't race updating them from
multiple places, and free the queue when updating them so that
in-progress I/O submissions don't see half-updated limits.

Also use the chance to clean up variable names to standard ones.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Assign all queue limits through a local queue_limits variable and
queue_limits_commit_update so that we can't race updating them from
multiple places, and freeze the queue when updating them so that
in-progress I/O submissions don't see half-updated limits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-12-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Consolidate setting zone-related queue limits in sd_zbc_read_zones
instead of splitting them between sd_zbc_revalidate_zones and
sd_zbc_read_zones, and move the early_zone_information initialization
in sd_zbc_read_zones above setting up the queue limits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-11-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Split the logic to pick the right discard mode into a little helper
to prepare for further changes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Fall through to the main call to blk_queue_max_discard_sectors given that
max_blocks has been initialized to zero above instead of duplicating the
call.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-9-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add helper to disable WRITE SAME when it is not supported and use it
instead of sd_config_write_same in the I/O completion handler.  This
avoids touching more fields than required in the I/O completion handler
and  prepares for converting sd to use the atomic queue limits API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-8-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add helper to disable discard when it is not supported and use it
instead of sd_config_discard in the I/O completion handler.  This avoids
touching more fields than required in the I/O completion handler and
prepares for converting sd to use the atomic queue limits API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Don't reset the discard settings to no-op over and over when a user
writes to the provisioning attribute as that is already the default
mode for ZBC devices.  In hindsight we should have made writing to
the attribute fail for ZBC devices, but the code has probably been
around for far too long to change this now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-6-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

The soft max_sectors limit is normally capped by the hardware limits and
an arbitrary upper limit enforced by the kernel, but can be modified by
the user.  A few drivers want to increase this limit (nbd, rbd) or
adjust it up or down based on hardware capabilities (sd).

Change blk_validate_limits to default max_sectors to the optimal I/O
size, or upgrade it to the preferred minimal I/O size if that is
larger than the kernel default if no optimal I/O size is provided based
on the logic in the SD driver.

This keeps the existing kernel default for drivers that do not provide
an io_opt or very big io_min value, but picks a much more useful
default for those who provide these hints, and allows to remove the
hacks to set the user max_sectors limit in nbd, rbd and sd.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Acked-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-5-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Commit 16d80c54 ("rbd: set io_min, io_opt and discard_granularity to
alloc_size") lowered the io_opt size for rbd from objset_bytes which is
4MB for typical setup to alloc_size which is typically 64KB.

The commit mostly talks about discard behavior and does mention io_min
in passing.  Reducing io_opt means reducing the readahead size, which
seems counter-intuitive given that rbd currently abuses the user
max_sectors setting to actually increase the I/O size.  Switch back
to the old setting to allow larger reads (the readahead size despite it's
name actually limits the size of any buffered read) and to prepare
for using io_opt in the max_sectors calculation and getting drivers out
of the business of overriding the max_user_sectors value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-4-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Discard and Write Zeroes are different operation and implemented
by different fallocate opcodes for ubd.  If one fails the other one
can work and vice versa.

Split the code to disable the operations in ubd_handler to only
disable the operation that actually failed.

Fixes: 50109b5a ("um: Add support for DISCARD in the UBD Driver")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Instead of a separate handler function that leaves no work in the
interrupt hanler itself, split out a per-request end I/O helper and
clean up the coding style and variable naming while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://lore.kernel.org/r/20240531074837.1648501-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add an entry for the Rust block device driver abstractions.
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Link: https://lore.kernel.org/r/20240611114551.228679-4-nmi@metaspace.dkSigned-off-by: Jens Axboe <axboe@kernel.dk>

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

Add initial abstractions for working with blk-mq.

This patch is a maintained, refactored subset of code originally published
by Wedson Almeida Filho <wedsonaf@gmail.com> [1].

[1] https://github.com/wedsonaf/linux/tree/f2cfd2fe0e2ca4e90994f96afe268bbd4382a891/rust/kernel/blk/mq.rs

Cc: Wedson Almeida Filho <wedsonaf@gmail.com>
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240611114551.228679-2-nmi@metaspace.dkSigned-off-by: Jens Axboe <axboe@kernel.dk>