[PATCH v2 26/46] mm: rmap: provide pte_order in page_vma_mapped_walk

[James Houghton <jthoughton@xxxxxxxxxx>]

page_vma_mapped_walk callers will need this information to know how
HugeTLB pages are mapped. pte_order only applies if pte is not NULL.

Signed-off-by: James Houghton <jthoughton@xxxxxxxxxx>

diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index a4570da03e58..87a2c7f422bf 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -387,6 +387,7 @@ struct page_vma_mapped_walk {
 	pmd_t *pmd;
 	pte_t *pte;
 	spinlock_t *ptl;
+	unsigned int pte_order;
 	unsigned int flags;
 };
 
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 4e448cfbc6ef..08295b122ad6 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -16,6 +16,7 @@ static inline bool not_found(struct page_vma_mapped_walk *pvmw)
 static bool map_pte(struct page_vma_mapped_walk *pvmw)
 {
 	pvmw->pte = pte_offset_map(pvmw->pmd, pvmw->address);
+	pvmw->pte_order = 0;
 	if (!(pvmw->flags & PVMW_SYNC)) {
 		if (pvmw->flags & PVMW_MIGRATION) {
 			if (!is_swap_pte(*pvmw->pte))
@@ -177,6 +178,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 		if (!pvmw->pte)
 			return false;
 
+		pvmw->pte_order = huge_page_order(hstate);
 		pvmw->ptl = huge_pte_lock(hstate, mm, pvmw->pte);
 		if (!check_pte(pvmw))
 			return not_found(pvmw);
@@ -272,6 +274,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 				}
 				pte_unmap(pvmw->pte);
 				pvmw->pte = NULL;
+				pvmw->pte_order = 0;
 				goto restart;
 			}
 			pvmw->pte++;
-- 
2.39.2.637.g21b0678d19-goog