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

[Caleb Sander Mateos]

On Sun, Jul 12, 2026 at 4:09 PM Martin K. Petersen
<martin.petersen at oracle.com> wrote:
>
>
> Caleb,
>
> > The block integrity layer currently sets the integrity seed (initial
> > reference tag) in units of 512-byte sectors.
>
> ... because that is the fundamental addressing unit in the block layer.
>
> > However, Type 1 and Type 2 ref tags are actually in units of integrity
> > intervals.
>
> They are not in units of anything until they reach their final
> protection envelope.
>
> > On devices with integrity interval size > 512 bytes, ref tags are
> > seeded incorrectly.
>
> The bip seed is whatever the caller decides it should be. The integrity
> interval size is irrelevant. As is the destination LBA.
>
> > 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.
>
> Then there's a problem with how we handle REQ_OP_ZONE_APPEND. For NVMe,
> the PIREMAP flag should address this issue by remapping the written ref
> tags based on their ultimate destination LBA.

Yes, it looks like PIREMAP should allow this to work. But Christoph
reported that ref tags weren't working correctly with
REQ_OP_ZONE_APPEND:
https://lore.kernel.org/linux-block/20260624080014.1998650-3-hch@lst.de/T/#u

Christoph, were you testing with an NVMe ZNS device?

Thanks,
Caleb