On Mon, Jun 07, 2021 at 03:42:19PM -0500, Alex Sierra wrote: > +++ b/include/linux/dax.h > @@ -243,6 +243,16 @@ static inline bool dax_mapping(struct address_space *mapping) > return mapping->host && IS_DAX(mapping->host); > } > > +static inline bool dax_layout_is_idle_page(struct page *page) > +{ > + return page_ref_count(page) == 1; > +} We already have something called an idle page, and that's quite a different thing from this. How about dax_page_unused() (it's a use count, so once it's got down to its minimum value, it's unused)?