mm: Add DEFINE_PAGE_VMA_WALK and DEFINE_FOLIO_VMA_WALK

Instead of declaring a struct page_vma_mapped_walk directly,
use these helpers to allow us to transition to a PFN approach in the
following patches.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

1 files changed, 1 insertions, 4 deletions

diff --git a/mm/ksm.c b/mm/ksm.c
index c5a4403b5dc9..ea82fef93a31 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1034,10 +1034,7 @@ static int write_protect_page(struct vm_area_struct *vma, struct page *page,
 			      pte_t *orig_pte)
 {
 	struct mm_struct *mm = vma->vm_mm;
-	struct page_vma_mapped_walk pvmw = {
-		.page = page,
-		.vma = vma,
-	};
+	DEFINE_PAGE_VMA_WALK(pvmw, page, vma, 0, 0);
 	int swapped;
 	int err = -EFAULT;
 	struct mmu_notifier_range range;