hugetlb: convert remove_pool_huge_page() to remove_pool_hugetlb_folio()

Convert the callers to expect a folio and remove the unnecesary conversion
back to a struct page.

Link: https://lkml.kernel.org/r/20230824141325.2704553-4-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/hugetlb.c

@@ -1446,7 +1446,7 @@ static int hstate_next_node_to_alloc(struct hstate *h,
 }
 
 /*
- * helper for remove_pool_huge_page() - return the previously saved
+ * helper for remove_pool_hugetlb_folio() - return the previously saved
  * node ["this node"] from which to free a huge page.  Advance the
  * next node id whether or not we find a free huge page to free so
  * that the next attempt to free addresses the next node.
@@ -2222,9 +2222,8 @@ static int alloc_pool_huge_page(struct hstate *h, nodemask_t *nodes_allowed,
  * an additional call to free the page to low level allocators.
  * Called with hugetlb_lock locked.
  */
-static struct page *remove_pool_huge_page(struct hstate *h,
-						nodemask_t *nodes_allowed,
-						 bool acct_surplus)
+static struct folio *remove_pool_hugetlb_folio(struct hstate *h,
+		nodemask_t *nodes_allowed, bool acct_surplus)
 {
 	int nr_nodes, node;
 	struct folio *folio = NULL;
@@ -2244,7 +2243,7 @@ static struct page *remove_pool_huge_page(struct hstate *h,
 		}
 	}
 
-	return &folio->page;
+	return folio;
 }
 
 /*
@@ -2598,7 +2597,6 @@ static void return_unused_surplus_pages(struct hstate *h,
 					unsigned long unused_resv_pages)
 {
 	unsigned long nr_pages;
-	struct page *page;
 	LIST_HEAD(page_list);
 
 	lockdep_assert_held(&hugetlb_lock);
@@ -2619,15 +2617,17 @@ static void return_unused_surplus_pages(struct hstate *h,
 	 * evenly across all nodes with memory. Iterate across these nodes
 	 * until we can no longer free unreserved surplus pages. This occurs
 	 * when the nodes with surplus pages have no free pages.
-	 * remove_pool_huge_page() will balance the freed pages across the
+	 * remove_pool_hugetlb_folio() will balance the freed pages across the
 	 * on-line nodes with memory and will handle the hstate accounting.
 	 */
 	while (nr_pages--) {
-		page = remove_pool_huge_page(h, &node_states[N_MEMORY], 1);
-		if (!page)
+		struct folio *folio;
+
+		folio = remove_pool_hugetlb_folio(h, &node_states[N_MEMORY], 1);
+		if (!folio)
 			goto out;
 
-		list_add(&page->lru, &page_list);
+		list_add(&folio->lru, &page_list);
 	}
 
 out:
@@ -3472,7 +3472,6 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
 			      nodemask_t *nodes_allowed)
 {
 	unsigned long min_count, ret;
-	struct page *page;
 	LIST_HEAD(page_list);
 	NODEMASK_ALLOC(nodemask_t, node_alloc_noretry, GFP_KERNEL);
 
@@ -3594,11 +3593,13 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
 	 * Collect pages to be removed on list without dropping lock
 	 */
 	while (min_count < persistent_huge_pages(h)) {
-		page = remove_pool_huge_page(h, nodes_allowed, 0);
-		if (!page)
+		struct folio *folio;
+
+		folio = remove_pool_hugetlb_folio(h, nodes_allowed, 0);
+		if (!folio)
 			break;
 
-		list_add(&page->lru, &page_list);
+		list_add(&folio->lru, &page_list);
 	}
 	/* free the pages after dropping lock */
 	spin_unlock_irq(&hugetlb_lock);