/*
 	 * Please do not reorder this without considering how mm/ksm.c's
 	 * get_ksm_page() depends upon ksm_migrate_page() and PageSwapCache().
 	 */
-	if (PageSwapCache(page))
-		ClearPageSwapCache(page);
-	ClearPagePrivate(page);
-	set_page_private(page, 0);
+	if (folio_swapcache(folio))
+		folio_clear_swapcache_flag(folio);
+	folio_clear_private_flag(folio);
+
+	/* page->private contains hugetlb specific flags */
+	if (!folio_hugetlb(folio))
+		folio->private = NULL;

Ymmm. Dosn't the ->private handling change now?  Given that you
added a comment it seems intentional, but I do not understand why
it changes as part of the conversion.