[PATCH mm-unstable v2 02/10] mm/hugetlb: convert destroy_compound_gigantic_page() to folios

[Sidhartha Kumar]

Convert page operations within __destroy_compound_gigantic_page() to the
corresponding folio operations.

Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx>
---
 mm/hugetlb.c | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 157f2392c64f..5edb81541ede 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1325,43 +1325,40 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
 		nr_nodes--)
 
 /* used to demote non-gigantic_huge pages as well */
-static void __destroy_compound_gigantic_page(struct page *page,
+static void __destroy_compound_gigantic_folio(struct folio *folio,
 					unsigned int order, bool demote)
 {
 	int i;
 	int nr_pages = 1 << order;
 	struct page *p;
 
-	atomic_set(compound_mapcount_ptr(page), 0);
-	atomic_set(subpages_mapcount_ptr(page), 0);
-	atomic_set(compound_pincount_ptr(page), 0);
+	atomic_set(folio_mapcount_ptr(folio), 0);
+	atomic_set(folio_subpages_mapcount_ptr(folio), 0);
+	atomic_set(folio_pincount_ptr(folio), 0);
 
 	for (i = 1; i < nr_pages; i++) {
-		p = nth_page(page, i);
+		p = folio_page(folio, i);
 		p->mapping = NULL;
 		clear_compound_head(p);
 		if (!demote)
 			set_page_refcounted(p);
 	}
 
-	set_compound_order(page, 0);
-#ifdef CONFIG_64BIT
-	page[1].compound_nr = 0;
-#endif
-	__ClearPageHead(page);
+	folio_set_compound_order(folio, 0);
+	folio_clear_head(folio);
 }
 
-static void destroy_compound_hugetlb_page_for_demote(struct page *page,
+static void destroy_compound_hugetlb_folio_for_demote(struct folio *folio,
 					unsigned int order)
 {
-	__destroy_compound_gigantic_page(page, order, true);
+	__destroy_compound_gigantic_folio(folio, order, true);
 }
 
 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
-static void destroy_compound_gigantic_page(struct page *page,
+static void destroy_compound_gigantic_folio(struct folio *folio,
 					unsigned int order)
 {
-	__destroy_compound_gigantic_page(page, order, false);
+	__destroy_compound_gigantic_folio(folio, order, false);
 }
 
 static void free_gigantic_page(struct page *page, unsigned int order)
@@ -1430,7 +1427,7 @@ static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
 	return NULL;
 }
 static inline void free_gigantic_page(struct page *page, unsigned int order) { }
-static inline void destroy_compound_gigantic_page(struct page *page,
+static inline void destroy_compound_gigantic_folio(struct folio *folio,
 						unsigned int order) { }
 #endif
 
@@ -1477,8 +1474,8 @@ static void __remove_hugetlb_page(struct hstate *h, struct page *page,
 	 *
 	 * For gigantic pages set the destructor to the null dtor.  This
 	 * destructor will never be called.  Before freeing the gigantic
-	 * page destroy_compound_gigantic_page will turn the compound page
-	 * into a simple group of pages.  After this the destructor does not
+	 * page destroy_compound_gigantic_folio will turn the folio into a
+	 * simple group of pages.  After this the destructor does not
 	 * apply.
 	 *
 	 * This handles the case where more than one ref is held when and
@@ -1559,6 +1556,7 @@ static void add_hugetlb_page(struct hstate *h, struct page *page,
 static void __update_and_free_page(struct hstate *h, struct page *page)
 {
 	int i;
+	struct folio *folio = page_folio(page);
 	struct page *subpage;
 
 	if (hstate_is_gigantic(h) && !gigantic_page_runtime_supported())
@@ -1587,8 +1585,8 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
 	 * Move PageHWPoison flag from head page to the raw error pages,
 	 * which makes any healthy subpages reusable.
 	 */
-	if (unlikely(PageHWPoison(page)))
-		hugetlb_clear_page_hwpoison(page);
+	if (unlikely(folio_test_hwpoison(folio)))
+		hugetlb_clear_page_hwpoison(&folio->page);
 
 	for (i = 0; i < pages_per_huge_page(h); i++) {
 		subpage = nth_page(page, i);
@@ -1604,7 +1602,7 @@ static void __update_and_free_page(struct hstate *h, struct page *page)
 	 */
 	if (hstate_is_gigantic(h) ||
 	    hugetlb_cma_page(page, huge_page_order(h))) {
-		destroy_compound_gigantic_page(page, huge_page_order(h));
+		destroy_compound_gigantic_folio(folio, huge_page_order(h));
 		free_gigantic_page(page, huge_page_order(h));
 	} else {
 		__free_pages(page, huge_page_order(h));
@@ -3435,6 +3433,7 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
 {
 	int i, nid = page_to_nid(page);
 	struct hstate *target_hstate;
+	struct folio *folio = page_folio(page);
 	struct page *subpage;
 	int rc = 0;
 
@@ -3453,10 +3452,10 @@ static int demote_free_huge_page(struct hstate *h, struct page *page)
 	}
 
 	/*
-	 * Use destroy_compound_hugetlb_page_for_demote for all huge page
+	 * Use destroy_compound_hugetlb_folio_for_demote for all huge page
 	 * sizes as it will not ref count pages.
 	 */
-	destroy_compound_hugetlb_page_for_demote(page, huge_page_order(h));
+	destroy_compound_hugetlb_folio_for_demote(folio, huge_page_order(h));
 
 	/*
 	 * Taking target hstate mutex synchronizes with set_max_huge_pages.
-- 
2.38.1