1 files changed, 32 insertions, 14 deletions

diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 74d2de15fb5e..81839a9e74f1 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -13,7 +13,8 @@ static inline bool not_found(struct page_vma_mapped_walk *pvmw)
 	return false;
 }
 
-static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
+static bool map_pte(struct page_vma_mapped_walk *pvmw, pmd_t *pmdvalp,
+		    spinlock_t **ptlp)
 {
 	pte_t ptent;
 
@@ -25,6 +26,7 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
 		return !!pvmw->pte;
 	}
 
+again:
 	/*
 	 * It is important to return the ptl corresponding to pte,
 	 * in case *pvmw->pmd changes underneath us; so we need to
@@ -32,8 +34,8 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
 	 * proceeds to loop over next ptes, and finds a match later.
 	 * Though, in most cases, page lock already protects this.
 	 */
-	pvmw->pte = pte_offset_map_nolock(pvmw->vma->vm_mm, pvmw->pmd,
-					  pvmw->address, ptlp);
+	pvmw->pte = pte_offset_map_rw_nolock(pvmw->vma->vm_mm, pvmw->pmd,
+					     pvmw->address, pmdvalp, ptlp);
 	if (!pvmw->pte)
 		return false;
 
@@ -67,8 +69,13 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
 	} else if (!pte_present(ptent)) {
 		return false;
 	}
+	spin_lock(*ptlp);
+	if (unlikely(!pmd_same(*pmdvalp, pmdp_get_lockless(pvmw->pmd)))) {
+		pte_unmap_unlock(pvmw->pte, *ptlp);
+		goto again;
+	}
 	pvmw->ptl = *ptlp;
-	spin_lock(pvmw->ptl);
+
 	return true;
 }
 
@@ -278,7 +285,7 @@ restart:
 			step_forward(pvmw, PMD_SIZE);
 			continue;
 		}
-		if (!map_pte(pvmw, &ptl)) {
+		if (!map_pte(pvmw, &pmde, &ptl)) {
 			if (!pvmw->pte)
 				goto restart;
 			goto next_pte;
@@ -305,8 +312,13 @@ next_pte:
 		} while (pte_none(ptep_get(pvmw->pte)));
 
 		if (!pvmw->ptl) {
+			spin_lock(ptl);
+			if (unlikely(!pmd_same(pmde, pmdp_get_lockless(pvmw->pmd)))) {
+				pte_unmap_unlock(pvmw->pte, ptl);
+				pvmw->pte = NULL;
+				goto restart;
+			}
 			pvmw->ptl = ptl;
-			spin_lock(pvmw->ptl);
 		}
 		goto this_pte;
 	} while (pvmw->address < end);
@@ -314,17 +326,21 @@ next_pte:
 	return false;
 }
 
+#ifdef CONFIG_MEMORY_FAILURE
 /**
  * page_mapped_in_vma - check whether a page is really mapped in a VMA
  * @page: the page to test
  * @vma: the VMA to test
  *
- * Returns 1 if the page is mapped into the page tables of the VMA, 0
- * if the page is not mapped into the page tables of this VMA.  Only
- * valid for normal file or anonymous VMAs.
+ * Return: The address the page is mapped at if the page is in the range
+ * covered by the VMA and present in the page table.  If the page is
+ * outside the VMA or not present, returns -EFAULT.
+ * Only valid for normal file or anonymous VMAs.
  */
-int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
+unsigned long page_mapped_in_vma(const struct page *page,
+		struct vm_area_struct *vma)
 {
+	const struct folio *folio = page_folio(page);
 	struct page_vma_mapped_walk pvmw = {
 		.pfn = page_to_pfn(page),
 		.nr_pages = 1,
@@ -332,11 +348,13 @@ int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
 		.flags = PVMW_SYNC,
 	};
 
-	pvmw.address = vma_address(page, vma);
+	pvmw.address = vma_address(vma, page_pgoff(folio, page), 1);
 	if (pvmw.address == -EFAULT)
-		return 0;
+		goto out;
 	if (!page_vma_mapped_walk(&pvmw))
-		return 0;
+		return -EFAULT;
 	page_vma_mapped_walk_done(&pvmw);
-	return 1;
+out:
+	return pvmw.address;
 }
+#endif