[PATCH 08/20] nvme: call nvme_identify_ns as the first thing in nvme_alloc_ns_block

[Sagi Grimberg]

> Check if the namespace actually exists as the very first thing and don't
> bother with any extra work if not.  This should speed up and simplify
> the sequential scanning for NVMe 1.0 devices.

What exactly is this speeding up? Its just a few assignments+allocations