Re: [PATCH 14/15] libnvdimm: support read-only btt backing devices

Jeff Moyer
2015-06-22T19:11:16Z

Dan Williams <dan.j.williams@intel.com> writes:

>>> Direct I/O using application can make assumption if they know the sector
>>> size, and we must have a way for them to be able to see our new
>>> "subsector sector size".
>>
>> You need to let them determine that when NOT using the btt, yes. Right
>> now, I don't think there's a way to determine what the underlying atomic
>> write unit is. That's something the NFIT spec probably should have
>> defined.
>
> There are no atomic write units for NFIT to advertise beyond cpu register width.

That would be useful information for the platform to provide, instead of
requiring the o/s or applications to infer it.

Cheers,
Jeff