[PATCH, RFC] nvme: Do not test the read-ahead flag in cmd_flags

[Jens Axboe]

On 09/14/2016 08:47 AM, Christoph Hellwig wrote:
> On Wed, Sep 14, 2016 at 08:43:48AM -0600, Jens Axboe wrote:
>>> It's indeed a bug, but the questions is if why we shouldn't pass
>>> REQ_RAHEAD down to the request layer.  It's a useful attribute,
>>> and NVMe devices could make use of it.
>>
>> Indeed, seems a shame to lose this hint.
>
> It currently doesn't work.  But it would be useful to actually pass

Right, hence we lose it when mapping from a bio to a request.

> it through.  That being said we currently have a complete mess with
> the common vs request only flags, both about their placement in the
> enum and inclusion in the common mask.  Making it worse it seems
> like REQ_NOMERGE actually is used in both currently and not actually
> expecting propagation.

It would be nice to harden that.

-- 
Jens Axboe