[PATCH v4 0/5] block: use integrity interval instead of sector as seed

[Caleb Sander Mateos <csander@purestorage.com>]

The block integrity layer currently sets the integrity seed (initial
reference tag) in units of 512-byte sectors. However, Type 1 and Type 2
ref tags are actually in units of integrity intervals. On devices with
integrity interval size > 512 bytes, ref tags are seeded incorrectly.

Ref tag "remapping" in blk_integrity_{prepare,complete}() covers up this
ref tag seed discrepancy by offsetting all ref tags in each bio to
convert to/from the absolute integrity interval numbers. But
REQ_OP_ZONE_APPEND operations don't have their ref tags remapped, so the
ref tags using units of sectors will be stored to the device. As future
optimizations, the ref tag remapping could be avoided entirely on NVMe
and some SCSI devices by passing the ref tag seed instead of the
absolute integrity interval as the expected initial ref tag.

So avoid relying on remapping to convert between the ref tag seed in
units of sectors and stored ref tags in units of integrity intervals.
Initialize the ref tag seed as the integrity interval, not sector.

The subsequent commits clean up the integrity ref tag seed code a bit.

v4:
- Drop patch already applied

v3: https://lore.kernel.org/linux-block/20260417015732.2692434-1-csander@purestorage.com/T/
- Drop bi and bip arguments to bip_set_seed() (Christoph)

v2:
- Reorder fixes before refactoring commits
- Use u64, SECTOR_SHIFT (Christoph)
- Don't take sector_t in bip_set_seed() (Christoph)

Caleb Sander Mateos (5):
  block: use integrity interval instead of sector as seed
  blk-integrity: take u64 in bio_integrity_intervals()
  bio-integrity-fs: use integrity interval instead of sector as seed
  t10-pi: use bio_integrity_intervals() helper
  blk-integrity: avoid sector_t in bip_{get,set}_seed()

 block/bio-integrity-fs.c            |  2 +-
 block/bio-integrity.c               |  4 ++--
 block/t10-pi.c                      |  7 ++++---
 drivers/nvme/target/io-cmd-bdev.c   |  3 +--
 drivers/target/target_core_iblock.c |  3 +--
 include/linux/bio-integrity.h       | 11 -----------
 include/linux/blk-integrity.h       | 27 ++++++++++++++++++++-------
 include/linux/bvec.h                |  1 +
 8 files changed, 30 insertions(+), 28 deletions(-)

-- 
2.54.0