[Question] About z3fold page migration

[linmiaohe]

Hi Vitaly:

	Many thanks for your brilliant z3fold code. I am reading it and have some questions about it. It's very nice of you if you can explain it for me.
	1.page->private is used in z3fold but PagePrivate flag is never set, should we SetPagePrivate for it?
	2.Since PagePrivate flag is never set, why we ClearPagePrivate in free_z3fold_page and z3fold_page_migrate?
	3.Should we add page to the unbuddied list in z3fold_page_putback() when zhdr->refcount does not reach 0 since we remove it from unbuddied list
in z3fold_page_isolate? Or When we will add page to the unbuddied list after z3fold_page_putback?

	Thanks a lot in advance. And waiting for your reply. :)