[PATCH 3/3] nvme: don't set io_opt if NOWS is zero

[Keith Busch]

On Mon, Jul 01, 2024 at 07:17:52AM +0200, Christoph Hellwig wrote:
> NOWS is one of the annoying "0's based values" in NVMe, where 0 means one
> and we thus can't detect if it isn't set.  

We can detect if it is set based on the namespace features flags,
though.

> Thus a NOWS value of 0 means
> that the Namespace Optimal Write Size is a single LBA, which is clearly
> bogus.  Ignore the value in that case and don't propagate an io_opt
> value to the block layer.

Hm, why is that clearly bogus? Optane SSDs were optimized for
single-sector writes.