mm/huge_memory: page_try_dup_anon_rmap() -> folio_try_dup_anon_rmap_pmd()

Let's convert copy_huge_pmd() and fixup the comment in copy_huge_pud(). 
While at it, perform more folio conversion in copy_huge_pmd().

Link: https://lkml.kernel.org/r/20231220224504.646757-36-david@redhat.comSigned-off-by: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/huge_memory.c

@@ -1275,6 +1275,7 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 {
 	spinlock_t *dst_ptl, *src_ptl;
 	struct page *src_page;
+	struct folio *src_folio;
 	pmd_t pmd;
 	pgtable_t pgtable = NULL;
 	int ret = -ENOMEM;
@@ -1341,11 +1342,12 @@ int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 
 	src_page = pmd_page(pmd);
 	VM_BUG_ON_PAGE(!PageHead(src_page), src_page);
+	src_folio = page_folio(src_page);
 
-	get_page(src_page);
-	if (unlikely(page_try_dup_anon_rmap(src_page, true, src_vma))) {
+	folio_get(src_folio);
+	if (unlikely(folio_try_dup_anon_rmap_pmd(src_folio, src_page, src_vma))) {
 		/* Page maybe pinned: split and retry the fault on PTEs. */
-		put_page(src_page);
+		folio_put(src_folio);
 		pte_free(dst_mm, pgtable);
 		spin_unlock(src_ptl);
 		spin_unlock(dst_ptl);
@@ -1454,8 +1456,8 @@ int copy_huge_pud(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	}
 
 	/*
-	 * TODO: once we support anonymous pages, use page_try_dup_anon_rmap()
-	 * and split if duplicating fails.
+	 * TODO: once we support anonymous pages, use
+	 * folio_try_dup_anon_rmap_*() and split if duplicating fails.
 	 */
 	pudp_set_wrprotect(src_mm, addr, src_pud);
 	pud = pud_mkold(pud_wrprotect(pud));