[PATCH 5/9] libnvme: add support for retrieving namespace gendisk I/O statistics

[Daniel Wagner]

On Sat, Mar 21, 2026 at 08:58:04PM +0530, Nilay Shroff wrote:
> Gendisk I/O statistics provide useful insight into disk activity,
> including read/write/discard/flush operations, as well as information
> about in-flight I/Os and I/O timing.
> 
> Parsing these statistics allows users to determine the number of I/Os
> processed, time spent servicing I/O, number of sectors accessed, and
> the count of in-flight requests.
> 
> Add support for retrieving namespace gendisk I/O statistics. Also add
> support for computing deltas of these statistics between samples, such
> as I/O ticks, number of sectors, and number of serviced I/Os.
> 
> These metrics can be used by tools such as nvme-top to display real-time
> disk activity.

Same comments as in the previous patch.
  - error codes
  - is it necessary to expose 'cur', 'this' via the API?