kernel/linux.git/drivers/md/dm-zone.c, branch linux-7.1.y

dm: use READ_ONCE in dm_blk_report_zones

2026-01-14T12:12:21+00:00

The functon dm_blk_report_zones reads md->zone_revalidate_map, however it may change while the function is running. Use READ_ONCE. Signed-off-by: Mikulas Patocka Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones") Reviewed-by: Benjamin Marzinski

dm: fix unlocked test for dm_suspended_md

2026-01-14T12:12:02+00:00

The function dm_blk_report_zones tests if the device is suspended with the "dm_suspended_md" call. However, this function is called without holding any locks, so the device may be suspended just after it. Move the call to dm_suspended_md after dm_get_live_table, so that the device can't be suspended after the suspended state was tested. Signed-off-by: Mikulas Patocka Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones") Reviewed-by: Benjamin Marzinski

Merge tag 'for-6.19/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2025-12-11T03:13:29+00:00

Pull device mapper updates from Mikulas Patocka: - convert crypto_shash users to direct crypto library use with simpler and faster code and reduced stack usage (Eric Biggers): - the dm-verity SHA-256 conversion also teaches it to do two-way interleaved hashing for added performance - dm-crypt MD5 conversion (used for Loop-AES compatibility) - added document for for takeover/reshape raid1 -> raid5 examples (Heinz Mauelshagen) - fix dm-vdo kerneldoc warnings (Matthew Sakai) - various random fixes and cleanups * tag 'for-6.19/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (29 commits) dm pcache: fix segment info indexing dm pcache: fix cache info indexing dm-pcache: advance slot index before writing slot dm raid: add documentation for takeover/reshape raid1 -> raid5 table line examples dm log-writes: Add missing set_freezable() for freezable kthread dm-raid: fix possible NULL dereference with undefined raid type dm-snapshot: fix 'scheduling while atomic' on real-time kernels dm: ignore discard return value MAINTAINERS: add Benjamin Marzinski as a device mapper maintainer dm-mpath: Simplify the setup_scsi_dh code dm vdo: fix kerneldoc warnings dm-bufio: align write boundary on physical block size dm-crypt: enable DM_TARGET_ATOMIC_WRITES dm: test for REQ_ATOMIC in dm_accept_partial_bio() dm-verity: remove useless mempool dm-verity: disable recursive forward error correction dm-ebs: Mark full buffer dirty even on partial write dm mpath: enable DM_TARGET_ATOMIC_WRITES dm verity fec: Expose corrected block count via status dm: Don't warn if IMA_DISABLE_HTABLE is not enabled ...

dm: fix zone reset all operation processing

2025-11-13T16:10:04+00:00

dm_zone_get_reset_bitmap() is used to generate a bitmap of the zones of a zoned device target when a REQ_OP_ZONE_RESET_ALL request is being processed. This bitmap is built by executing a zone report with a report callback set to the function dm_zone_need_reset_cb() in struct dm_report_zones_args. However, the cb callback pointer is not anymore the same as the callback specified by callers of the blkdev_report_zones() function. Rather, this is a DM internal callback and report zones callback functions from blkdev_report_zones() are passed using struct blk_report_zones_args, introduced with commit db9aed869f34 ("block: introduce disk_report_zone()"). This commit changed the DM main report zones callback handler function dm_report_zones_cb() to call the new disk_report_zone() so that callback functions from blkdev_report_zones() are executed, and this change resulted in the DM internal dm_zone_need_reset_cb() callback function to not be executed anymore, turning any REQ_OP_ZONE_RESET_ALL request into a no-op. Fix this by calling in dm_report_zones_cb() the DM internal cb function specified in struct dm_report_zones_args. Fixes: db9aed869f34 ("block: introduce disk_report_zone()"). Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: introduce disk_report_zone()

2025-11-05T15:07:21+00:00

Commit b76b840fd933 ("dm: Fix dm-zoned-reclaim zone write pointer alignment") introduced an indirect call for the callback function of a report zones executed with blkdev_report_zones(). This is necessary so that the function disk_zone_wplug_sync_wp_offset() can be called to refresh a zone write plug zone write pointer offset after a write error. However, this solution makes following the path of a zone information harder to understand. Clean this up by introducing the new blk_report_zones_args structure to define a zone report callback and its private data and introduce the helper function disk_report_zone() which calls both disk_zone_wplug_sync_wp_offset() and the zone report user callback function for all zones of a zone report. This helper function must be called by all block device drivers that implement the report zones block operation in order to correctly report a zone information. All block device drivers supporting the report_zones block operation are updated to use this new scheme. Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Chaitanya Kulkarni Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe

dm: remove useless md->nr_zones variable

2025-10-20T13:21:56+00:00

md->nr_zones is no longer used for anything. Remove it. Signed-off-by: Benjamin Marzinski Reviewed-by: Damien Le Moal Signed-off-by: Mikulas Patocka

dm: Remove unnecessary return in dm_zone_endio()

2025-06-27T10:59:11+00:00

The return statement at the end of dm_zone_endio() is not needed. Remove it. Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Signed-off-by: Mikulas Patocka

dm-zone: Use bdev_*() helper functions where applicable

2025-05-15T13:55:07+00:00

Improve code readability by using bdev_is_zone_aligned() and bdev_offset_from_zone_start() where applicable. No functionality has been changed. This patch is a reworked version of a patch from Pankaj Raghav. See also https://lore.kernel.org/linux-block/20220923173618.6899-11-p.raghav@samsung.com/. Cc: Damien Le Moal Cc: Pankaj Raghav Signed-off-by: Bart Van Assche Reviewed-by: Damien Le Moal Signed-off-by: Mikulas Patocka

dm: fix native zone append devices on top of emulated ones

2025-05-04T09:35:05+00:00

If a DM device that can pass down zone append commands is stacked on top of a device that emulates zone append commands, it will allocate zone append emulation resources, even though it doesn't use them. This is because the underlying device will have max_hw_zone_append_sectors set to 0 to request zone append emulation. When the DM device is stacked on top of it, it will inherit that max_hw_zone_append_sectors limit, despite being able to pass down zone append bios. Solve this by making sure max_hw_zone_append_sectors is non-zero for DM devices that do not need zone append emulation. Reviewed-by: Damien Le Moal Tested-by: Damien Le Moal Signed-off-by: Benjamin Marzinski Signed-off-by: Mikulas Patocka

dm: limit swapping tables for devices with zone write plugs

2025-05-04T09:35:05+00:00

dm_revalidate_zones() only allowed new or previously unzoned devices to call blk_revalidate_disk_zones(). If the device was already zoned, disk->nr_zones would always equal md->nr_zones, so dm_revalidate_zones() returned without doing any work. This would make the zoned settings for the device not match the new table. If the device had zone write plug resources, it could run into errors like bdev_zone_is_seq() reading invalid memory because disk->conv_zones_bitmap was the wrong size. If the device doesn't have any zone write plug resources, calling blk_revalidate_disk_zones() will always correctly update device. If blk_revalidate_disk_zones() fails, it can still overwrite or clear the current disk->nr_zones value. In this case, DM must restore the previous value of disk->nr_zones, so that the zoned settings will continue to match the previous value that it fell back to. If the device already has zone write plug resources, blk_revalidate_disk_zones() will not correctly update them, if it is called for arbitrary zoned device changes. Since there is not much need for this ability, the easiest solution is to disallow any table reloads that change the zoned settings, for devices that already have zone plug resources. Specifically, if a device already has zone plug resources allocated, it can only switch to another zoned table that also emulates zone append. Also, it cannot change the device size or the zone size. A device can switch to an error target. Fixes: bb37d77239af2 ("dm: introduce zone append emulation") Reviewed-by: Damien Le Moal Tested-by: Damien Le Moal Signed-off-by: Benjamin Marzinski Signed-off-by: Mikulas Patocka