1 files changed, 24 insertions, 21 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 65c289c13b58..9474dbc150ed 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2335,13 +2335,13 @@ static void unmap_page(struct page *page)
 	VM_BUG_ON_PAGE(!unmap_success, page);
 }
 
-static void remap_page(struct page *page)
+static void remap_page(struct page *page, unsigned int nr)
 {
 	int i;
 	if (PageTransHuge(page)) {
 		remove_migration_ptes(page, page, true);
 	} else {
-		for (i = 0; i < HPAGE_PMD_NR; i++)
+		for (i = 0; i < nr; i++)
 			remove_migration_ptes(page + i, page + i, true);
 	}
 }
@@ -2419,6 +2419,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 	struct lruvec *lruvec;
 	struct address_space *swap_cache = NULL;
 	unsigned long offset = 0;
+	unsigned int nr = thp_nr_pages(head);
 	int i;
 
 	lruvec = mem_cgroup_page_lruvec(head, pgdat);
@@ -2434,7 +2435,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 		xa_lock(&swap_cache->i_pages);
 	}
 
-	for (i = HPAGE_PMD_NR - 1; i >= 1; i--) {
+	for (i = nr - 1; i >= 1; i--) {
 		__split_huge_page_tail(head, i, lruvec, list);
 		/* Some pages can be beyond i_size: drop them from page cache */
 		if (head[i].index >= end) {
@@ -2454,7 +2455,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 
 	ClearPageCompound(head);
 
-	split_page_owner(head, HPAGE_PMD_ORDER);
+	split_page_owner(head, nr);
 
 	/* See comment in __split_huge_page_tail() */
 	if (PageAnon(head)) {
@@ -2473,9 +2474,15 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 
 	spin_unlock_irqrestore(&pgdat->lru_lock, flags);
 
-	remap_page(head);
+	remap_page(head, nr);
 
-	for (i = 0; i < HPAGE_PMD_NR; i++) {
+	if (PageSwapCache(head)) {
+		swp_entry_t entry = { .val = page_private(head) };
+
+		split_swap_cluster(entry);
+	}
+
+	for (i = 0; i < nr; i++) {
 		struct page *subpage = head + i;
 		if (subpage == page)
 			continue;
@@ -2494,7 +2501,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
 
 int total_mapcount(struct page *page)
 {
-	int i, compound, ret;
+	int i, compound, nr, ret;
 
 	VM_BUG_ON_PAGE(PageTail(page), page);
 
@@ -2502,16 +2509,17 @@ int total_mapcount(struct page *page)
 		return atomic_read(&page->_mapcount) + 1;
 
 	compound = compound_mapcount(page);
+	nr = compound_nr(page);
 	if (PageHuge(page))
 		return compound;
 	ret = compound;
-	for (i = 0; i < HPAGE_PMD_NR; i++)
+	for (i = 0; i < nr; i++)
 		ret += atomic_read(&page[i]._mapcount) + 1;
 	/* File pages has compound_mapcount included in _mapcount */
 	if (!PageAnon(page))
-		return ret - compound * HPAGE_PMD_NR;
+		return ret - compound * nr;
 	if (PageDoubleMap(page))
-		ret -= HPAGE_PMD_NR;
+		ret -= nr;
 	return ret;
 }
 
@@ -2556,14 +2564,14 @@ int page_trans_huge_mapcount(struct page *page, int *total_mapcount)
 	page = compound_head(page);
 
 	_total_mapcount = ret = 0;
-	for (i = 0; i < HPAGE_PMD_NR; i++) {
+	for (i = 0; i < thp_nr_pages(page); i++) {
 		mapcount = atomic_read(&page[i]._mapcount) + 1;
 		ret = max(ret, mapcount);
 		_total_mapcount += mapcount;
 	}
 	if (PageDoubleMap(page)) {
 		ret -= 1;
-		_total_mapcount -= HPAGE_PMD_NR;
+		_total_mapcount -= thp_nr_pages(page);
 	}
 	mapcount = compound_mapcount(page);
 	ret += mapcount;
@@ -2580,9 +2588,9 @@ bool can_split_huge_page(struct page *page, int *pextra_pins)
 
 	/* Additional pins from page cache */
 	if (PageAnon(page))
-		extra_pins = PageSwapCache(page) ? HPAGE_PMD_NR : 0;
+		extra_pins = PageSwapCache(page) ? thp_nr_pages(page) : 0;
 	else
-		extra_pins = HPAGE_PMD_NR;
+		extra_pins = thp_nr_pages(page);
 	if (pextra_pins)
 		*pextra_pins = extra_pins;
 	return total_mapcount(page) == page_count(page) - extra_pins - 1;
@@ -2709,12 +2717,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 		}
 
 		__split_huge_page(page, list, end, flags);
-		if (PageSwapCache(head)) {
-			swp_entry_t entry = { .val = page_private(head) };
-
-			ret = split_swap_cluster(entry);
-		} else
-			ret = 0;
+		ret = 0;
 	} else {
 		if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) {
 			pr_alert("total_mapcount: %u, page_count(): %u\n",
@@ -2728,7 +2731,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 fail:		if (mapping)
 			xa_unlock(&mapping->i_pages);
 		spin_unlock_irqrestore(&pgdata->lru_lock, flags);
-		remap_page(head);
+		remap_page(head, thp_nr_pages(head));
 		ret = -EBUSY;
 	}