From mboxrd@z Thu Jan  1 00:00:00 1970
From: keith.busch@intel.com (Keith Busch)
Date: Wed, 28 Jan 2015 22:17:21 +0000 (UTC)
Subject: [PATCH] NVMe: Skip namespaces with interleaved meta-data
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On Wed, 28 Jan 2015, Martin K. Petersen wrote:
>>>>>> "Paul" == Paul Grabinar <paul.grabinar at ranbarg.com> writes:
>
> Paul> What happens if you switch on and off meta-data dynamically with
> Paul> /sys/block/<bdev>/integrity/write_generate and
> Paul> /sys/block/<bdev>/integrity/read_verify?
>
> I think the best way to go about dealing with all this is to set PRACT=1
> if no bip is attached to a bio bound for a name space formatted with PI.

That's an option for a subset of formats I eluded to before. It will
have the controller generate/strip if the metadata size 8 bytes with
DPS settings, but ignored otherwise. We still need a buffer if metadata
is not used for PI, or if the metadata size more than 8 bytes.