[PATCH 3/4] NVMe: End-to-end data protection

[Keith Busch]

On Mon, 11 Mar 2013, David.Darrington at hgst.com wrote:

> Is this correct:
>> +/*
>> + * Valid formats must have either no meta-data, or meta-data equal to
> the DIF
>> + * size and formatted for protection information. The driver has no use
> for
>> + * meta-data for any other purpose.
>> + */
>
> This patch fails nvme_alloc_ns() if there is meta data, but data
> protection is not enabled.
>
> Are there valid use cases where the driver passes through the meta-data to
> and from the controller, without generating  or verifying? Is it possible
> for applications to provided there own meta-data?

Other than the integrity extensions, I don't think there is anything in
a bio request that a block driver can use to set the command meta-data
pointer, whether an application wants to provide it or otherwise. Please
let me know if I've missed something, though.