[RFC PATCH] getting misc stats/attributes via xattr API

[Vivek Goyal]

On Mon, May 09, 2022 at 05:08:56PM +0200, Christian Brauner wrote:

[..]
> Having "xattr" in the system call name is just confusing. These are
> fundamentally not "real" xattrs and we shouldn't mix semantics. There
> should be a clear distinction between traditional xattrs and this vfs
> and potentially fs information providing interface.
> 
> Just thinking about what the manpage would look like. We would need to
> add a paragraph to xattr(7) explaining that in addition to the system.*,
> security.*, user.* and other namespaces we now also have a set of
> namespaces that function as ways to get information about mounts or
> other things instead of information attached to specific inodes.
> 
> That's super random imho. If I were to be presented with this manpage
> I'd wonder if someone was too lazy to add a proper new system call with
> it's own semantics for this and just stuffed it into an existing API
> because it provided matching system call arguments. We can add a new
> system call. It's not that we're running out of them.

FWIW, I also felt that using xattr API to get some sort of mount info felt
very non-intutive.

Thanks
Vivek