[PATCH rfc 6/6] nvme-fabrics: expose support for traddr as dns names to userspace

[Hannes Reinecke]

On 8/17/23 12:37, Sagi Grimberg wrote:
> 
>> [ .. ]
>>>> So I figured that the current approach would be preferable if
>>>> we accept how to expose that for a given kernel/driver, we can
>>>> accept dns names, or we cannot.
>>>>
>>>> What do others think? Christoph? Keith? Chaitanya?
>>>
>>> Anyone has feedback here?
>>>
>>> Seems that we want this, but the question is how to expose
>>> a new format of traddr (now can be a dns name) to userspace?
>>
>> Or have a new token 'traddr_dns' (instaed of 'traddr'), which would
>> hold the dnsname instead of the ip address.
>> And reject inputs where both are set.
>> Hmm?
> 
> I listed that as an option, you should read it.
> There are some disadvantages in doing that, it needs to co-exist
> with the mandatory (today) traddr, which is now will be mandatory
> only for fc. And also now the user will need to decide a conflicting
> existing functionality in nvme-cli that today accept dns names as
> a format to traddr, but now will need a different argument for
> passing it to the kernel.
> 
> Anyway, its possible, but more complicated IMO.
> 
> Plus, I also think that it can be useful for the kernel to signal
> capabilities and support for things that are not only valid tokens.

I cross-checked with nvme-cli; there we read the list of available 
tokens upon failure to give the user a hint which arguments are 
supported by any given kernel.
So by that regard it should be fine to just add 'dns' as a parameter
here.

Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare at suse.de                              +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew
Myers, Andrew McDonald, Martje Boudien Moerman