Backport three patches from series "mm: mapcount for large folios + page_mapcount() cleanups".

David Hildenbrand (3): [Backport] mm: allow for detecting underflows with page_mapcount() again [Backport] mm/rmap: always inline anon/file rmap duplication of a single PTE [Backport] mm/rmap: add fast-path for small folios when adding/removing/duplicating

include/linux/mm.h | 2 +- include/linux/rmap.h | 30 ++++++++++++++++++++++++++---- mm/rmap.c | 26 ++++++++++++++++---------- 3 files changed, 43 insertions(+), 15 deletions(-)