Re: [RFC PATCH] fs: Plumb case sensitivity bits into statx

[Chuck Lever <cel@kernel.org>]

On 10/3/25 5:15 PM, Gabriel Krisman Bertazi wrote:
> Chuck Lever <cel@kernel.org> writes:
> 
>> On 10/3/25 4:43 PM, Gabriel Krisman Bertazi wrote:
>>> Chuck Lever <cel@kernel.org> writes:
>>>
>>>> On 10/3/25 11:24 AM, Gabriel Krisman Bertazi wrote:
>>
>>>>> Does the protocol care about unicode version?  For userspace, it would
>>>>> be very relevant to expose it, as well as other details such as
>>>>> decomposition type.
>>>>
>>>> For the purposes of indicating case sensitivity and preservation, the
>>>> NFS protocol does not currently care about unicode version.
>>>>
>>>> But this is a very flexible proposal right now. Please recommend what
>>>> you'd like to see here. I hope I've given enough leeway that a unicode
>>>> version could be provided for other API consumers.
>>>
>>> But also, encoding version information is filesystem-wide, so it would
>>> fit statfs.
>>
>> ext4 appears to have the ability to set the case folding behavior
>> on each directory, that's why I started with statx.
> 
> Yes. casefold is set per directory, but the unicode version and
> casefolding semantics used by those casefolded directories are defined
> for the entire filesystem.
> 

Got it. That keeps the proposed statx changes simple. Let me look at how
extensible the statfs API is. Actually that falls a little outside of
the mission to support NFS's needs, so perhaps that should be a separate
effort? Let me know what you think.


-- 
Chuck Lever