Re: [PATCH v7 8/8] fsdax: add exception for reflinked files

[Christoph Hellwig]

On Thu, Oct 14, 2021 at 12:24:50PM -0700, Darrick J. Wong wrote:
> It feels a little dangerous to have page->mapping for shared storage
> point to an actual address_space when there are really multiple
> potential address_spaces out there.  If the mm or dax folks are ok with
> doing this this way then I'll live with it, but it seems like you'd want
> to leave /some/ kind of marker once you know that the page has multiple
> owners and therefore regular mm rmap via page->mapping won't work.

Yes, I thing poisoning page->mapping for the rmap enabled case seems
like a better idea.