As PageMappingFlags() now only indicates anon (incl. KSM) folios, we can
now simply check for PageAnon() and remove PageMappingFlags().

... and while at it, use the folio instead and operate on
folio->mapping.

Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
 include/linux/page-flags.h | 5 -----
 mm/page_alloc.c            | 7 +++----
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 094c8605a879e..fc159fa945351 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -723,11 +723,6 @@ static __always_inline bool folio_mapping_flags(const struct folio *folio)
 	return ((unsigned long)folio->mapping & PAGE_MAPPING_FLAGS) != 0;
 }
 
-static __always_inline bool PageMappingFlags(const struct page *page)
-{
-	return ((unsigned long)page->mapping & PAGE_MAPPING_FLAGS) != 0;
-}
-
 static __always_inline bool folio_test_anon(const struct folio *folio)
 {
 	return ((unsigned long)folio->mapping & PAGE_MAPPING_ANON) != 0;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 4aefeb2ae927f..78ddf1d43c6c1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1375,10 +1375,9 @@ __always_inline bool free_pages_prepare(struct page *page,
 			(page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
 		}
 	}
-	if (PageMappingFlags(page)) {
-		if (PageAnon(page))
-			mod_mthp_stat(order, MTHP_STAT_NR_ANON, -1);
-		page->mapping = NULL;
+	if (folio_test_anon(folio)) {
+		mod_mthp_stat(order, MTHP_STAT_NR_ANON, -1);
+		folio->mapping = NULL;
 	}
 	if (unlikely(page_has_type(page)))
 		/* Reset the page_type (which overlays _mapcount) */
-- 
2.49.0