mm/hugetlb: convert alloc_migrate_huge_page to folios

Change alloc_huge_page_nodemask() to alloc_hugetlb_folio_nodemask() and
alloc_migrate_huge_page() to alloc_migrate_hugetlb_folio().  Both
functions now return a folio rather than a page.

Link: https://lkml.kernel.org/r/20230113223057.173292-7-sidhartha.kumar@oracle.comSigned-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/hugetlb.h

@@ -719,7 +719,7 @@ struct huge_bootmem_page {
 int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list);
 struct page *alloc_huge_page(struct vm_area_struct *vma,
 				unsigned long addr, int avoid_reserve);
-struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
+struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
 				nodemask_t *nmask, gfp_t gfp_mask);
 struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
 				unsigned long address);
@@ -1040,8 +1040,8 @@ static inline struct page *alloc_huge_page(struct vm_area_struct *vma,
 	return NULL;
 }
 
-static inline struct page *
-alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
+static inline struct folio *
+alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
 			nodemask_t *nmask, gfp_t gfp_mask)
 {
 	return NULL;

mm/hugetlb.c

@@ -2419,7 +2419,7 @@ static struct folio *alloc_surplus_hugetlb_folio(struct hstate *h,
 	return folio;
 }
 
-static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
+static struct folio *alloc_migrate_hugetlb_folio(struct hstate *h, gfp_t gfp_mask,
 				     int nid, nodemask_t *nmask)
 {
 	struct folio *folio;
@@ -2439,7 +2439,7 @@ static struct page *alloc_migrate_huge_page(struct hstate *h, gfp_t gfp_mask,
 	 */
 	folio_set_hugetlb_temporary(folio);
 
-	return &folio->page;
+	return folio;
 }
 
 /*
@@ -2472,8 +2472,8 @@ struct folio *alloc_buddy_hugetlb_folio_with_mpol(struct hstate *h,
 	return folio;
 }
 
-/* page migration callback function */
-struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
+/* folio migration callback function */
+struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
 		nodemask_t *nmask, gfp_t gfp_mask)
 {
 	spin_lock_irq(&hugetlb_lock);
@@ -2484,12 +2484,12 @@ struct page *alloc_huge_page_nodemask(struct hstate *h, int preferred_nid,
 						preferred_nid, nmask);
 		if (folio) {
 			spin_unlock_irq(&hugetlb_lock);
-			return &folio->page;
+			return folio;
 		}
 	}
 	spin_unlock_irq(&hugetlb_lock);
 
-	return alloc_migrate_huge_page(h, gfp_mask, preferred_nid, nmask);
+	return alloc_migrate_hugetlb_folio(h, gfp_mask, preferred_nid, nmask);
 }
 
 /* mempolicy aware migration callback */
@@ -2498,16 +2498,16 @@ struct page *alloc_huge_page_vma(struct hstate *h, struct vm_area_struct *vma,
 {
 	struct mempolicy *mpol;
 	nodemask_t *nodemask;
-	struct page *page;
+	struct folio *folio;
 	gfp_t gfp_mask;
 	int node;
 
 	gfp_mask = htlb_alloc_mask(h);
 	node = huge_node(vma, address, gfp_mask, &mpol, &nodemask);
-	page = alloc_huge_page_nodemask(h, node, nodemask, gfp_mask);
+	folio = alloc_hugetlb_folio_nodemask(h, node, nodemask, gfp_mask);
 	mpol_cond_put(mpol);
 
-	return page;
+	return &folio->page;
 }
 
 /*

mm/migrate.c

@@ -1663,6 +1663,7 @@ struct page *alloc_migration_target(struct page *page, unsigned long private)
 	struct migration_target_control *mtc;
 	gfp_t gfp_mask;
 	unsigned int order = 0;
+	struct folio *hugetlb_folio = NULL;
 	struct folio *new_folio = NULL;
 	int nid;
 	int zidx;
@@ -1677,7 +1678,9 @@ struct page *alloc_migration_target(struct page *page, unsigned long private)
 		struct hstate *h = folio_hstate(folio);
 
 		gfp_mask = htlb_modify_alloc_mask(h, gfp_mask);
-		return alloc_huge_page_nodemask(h, nid, mtc->nmask, gfp_mask);
+		hugetlb_folio = alloc_hugetlb_folio_nodemask(h, nid,
+						mtc->nmask, gfp_mask);
+		return &hugetlb_folio->page;
 	}
 
 	if (folio_test_large(folio)) {