RFC: Marking file system va_filerev style

Hi,

Back in Sept. Richard reported a problem with a
FreeBSD server serving NFSv4 to Linux clients,
where the file attributes would get messed up
sometimes. (I can't recall if he posted me or a mailing
list.)

Anyhow, He tried a patch I gave him that told the
Linux client that the Change attribute (va_filerev)
increments for each change.
--> This appears to have fixed the problem.

However, this patch should really report what the
exported fs does w.r.t. va_filerev and not just guess
that it increments it.

So, the question is, how do I have file systems report
how they generate va_filerev?
My current thought is a new MNTK_xxx flag set by
the filesystem in its mount point to indicate it increments
it upon each change (which is what UFS and ZFS currently
does, I think?)

Does this sound reasonable?

Thanks for any comments, rick