[PATCH 1/3] tree: add support for discovering nvme paths using sysfs multipath link

[Nilay Shroff]

On 4/7/25 12:49 PM, Daniel Wagner wrote:
> Hi Nilay,
> 
> On Sat, Apr 05, 2025 at 06:32:47PM +0530, Nilay Shroff wrote:
>> With kernel v6.14, when NVMe native multipath is enabled, it is possible
>> to discover all paths to a shared namespace using the sysfs multipath link.
>> Leverage this functionality to update the path links for each shared NVMe
>> namespace, simplifying path discovery and management.
> 
> Since this is not a trivial change, could you extend this section a bit
> how it works? I understand from reading the patch, a new head namespace
> object is introduced which links to the different paths. 
Sure, I will update the commit and add more details.
> 
>> Please note that
>> this change is fully backward compatible.
> 
> Could you elaborate what that means? libnvme should still work on older
> kernels.
Yeah I think as it's given that libnvme should work with older kernels, I 
probably don't need to spell that out explicitly. The intention is just
to mention that this change would not break running libnvme on older kernels.
But I think I could remove this sentence.

> 
> Also could you add a tests for this? The is already a test for the
> current sysfs tree parser, see test/sysfs.
> 
Yes I'd add a testcase for this change. How about extending the existing 
test/sysfs/tree-dump.c? Or do you want me to add a new test case for this
change?

Thanks,
--Nilay