1 files changed, 88 insertions, 59 deletions

diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 49e0d28f0379..b38a1d00c971 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -3,7 +3,7 @@
 #include <linux/rmap.h>
 #include <linux/hugetlb.h>
 #include <linux/swap.h>
-#include <linux/swapops.h>
+#include <linux/leafops.h>
 
 #include "internal.h"
 
@@ -13,8 +13,10 @@ 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)
 {
+	bool is_migration;
 	pte_t ptent;
 
 	if (pvmw->flags & PVMW_SYNC) {
@@ -25,6 +27,8 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
 		return !!pvmw->pte;
 	}
 
+	is_migration = pvmw->flags & PVMW_MIGRATION;
+again:
 	/*
 	 * It is important to return the ptl corresponding to pte,
 	 * in case *pvmw->pmd changes underneath us; so we need to
@@ -32,18 +36,21 @@ 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;
 
 	ptent = ptep_get(pvmw->pte);
 
-	if (pvmw->flags & PVMW_MIGRATION) {
-		if (!is_swap_pte(ptent))
+	if (pte_none(ptent)) {
+		return false;
+	} else if (pte_present(ptent)) {
+		if (is_migration)
 			return false;
-	} else if (is_swap_pte(ptent)) {
-		swp_entry_t entry;
+	} else if (!is_migration) {
+		softleaf_t entry;
+
 		/*
 		 * Handle un-addressable ZONE_DEVICE memory.
 		 *
@@ -60,71 +67,73 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, spinlock_t **ptlp)
 		 * For more details on device private memory see HMM
 		 * (include/linux/hmm.h or mm/hmm.c).
 		 */
-		entry = pte_to_swp_entry(ptent);
-		if (!is_device_private_entry(entry) &&
-		    !is_device_exclusive_entry(entry))
+		entry = softleaf_from_pte(ptent);
+		if (!softleaf_is_device_private(entry) &&
+		    !softleaf_is_device_exclusive(entry))
 			return false;
-	} 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;
 }
 
 /**
- * check_pte - check if @pvmw->page is mapped at the @pvmw->pte
- * @pvmw: page_vma_mapped_walk struct, includes a pair pte and page for checking
+ * check_pte - check if [pvmw->pfn, @pvmw->pfn + @pvmw->nr_pages) is
+ * mapped at the @pvmw->pte
+ * @pvmw: page_vma_mapped_walk struct, includes a pair pte and pfn range
+ * for checking
+ * @pte_nr: the number of small pages described by @pvmw->pte.
  *
- * page_vma_mapped_walk() found a place where @pvmw->page is *potentially*
+ * page_vma_mapped_walk() found a place where pfn range is *potentially*
  * mapped. check_pte() has to validate this.
  *
  * pvmw->pte may point to empty PTE, swap PTE or PTE pointing to
  * arbitrary page.
  *
  * If PVMW_MIGRATION flag is set, returns true if @pvmw->pte contains migration
- * entry that points to @pvmw->page or any subpage in case of THP.
+ * entry that points to [pvmw->pfn, @pvmw->pfn + @pvmw->nr_pages)
  *
  * If PVMW_MIGRATION flag is not set, returns true if pvmw->pte points to
- * pvmw->page or any subpage in case of THP.
+ * [pvmw->pfn, @pvmw->pfn + @pvmw->nr_pages)
  *
  * Otherwise, return false.
  *
  */
-static bool check_pte(struct page_vma_mapped_walk *pvmw)
+static bool check_pte(struct page_vma_mapped_walk *pvmw, unsigned long pte_nr)
 {
 	unsigned long pfn;
 	pte_t ptent = ptep_get(pvmw->pte);
 
 	if (pvmw->flags & PVMW_MIGRATION) {
-		swp_entry_t entry;
-		if (!is_swap_pte(ptent))
-			return false;
-		entry = pte_to_swp_entry(ptent);
+		const softleaf_t entry = softleaf_from_pte(ptent);
 
-		if (!is_migration_entry(entry) &&
-		    !is_device_exclusive_entry(entry))
+		if (!softleaf_is_migration(entry))
 			return false;
 
-		pfn = swp_offset_pfn(entry);
-	} else if (is_swap_pte(ptent)) {
-		swp_entry_t entry;
+		pfn = softleaf_to_pfn(entry);
+	} else if (pte_present(ptent)) {
+		pfn = pte_pfn(ptent);
+	} else {
+		const softleaf_t entry = softleaf_from_pte(ptent);
 
 		/* Handle un-addressable ZONE_DEVICE memory */
-		entry = pte_to_swp_entry(ptent);
-		if (!is_device_private_entry(entry) &&
-		    !is_device_exclusive_entry(entry))
-			return false;
-
-		pfn = swp_offset_pfn(entry);
-	} else {
-		if (!pte_present(ptent))
+		if (!softleaf_is_device_private(entry) &&
+		    !softleaf_is_device_exclusive(entry))
 			return false;
 
-		pfn = pte_pfn(ptent);
+		pfn = softleaf_to_pfn(entry);
 	}
 
-	return (pfn - pvmw->pfn) < pvmw->nr_pages;
+	if ((pfn + pte_nr - 1) < pvmw->pfn)
+		return false;
+	if (pfn > (pvmw->pfn + pvmw->nr_pages - 1))
+		return false;
+	return true;
 }
 
 /* Returns true if the two ranges overlap.  Careful to not overflow. */
@@ -199,7 +208,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 			return false;
 
 		pvmw->ptl = huge_pte_lock(hstate, mm, pvmw->pte);
-		if (!check_pte(pvmw))
+		if (!check_pte(pvmw, pages_per_huge_page(hstate)))
 			return not_found(pvmw);
 		return true;
 	}
@@ -233,23 +242,23 @@ restart:
 		 */
 		pmde = pmdp_get_lockless(pvmw->pmd);
 
-		if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde) ||
-		    (pmd_present(pmde) && pmd_devmap(pmde))) {
+		if (pmd_trans_huge(pmde) || pmd_is_migration_entry(pmde)) {
 			pvmw->ptl = pmd_lock(mm, pvmw->pmd);
 			pmde = *pvmw->pmd;
 			if (!pmd_present(pmde)) {
-				swp_entry_t entry;
+				softleaf_t entry;
 
 				if (!thp_migration_supported() ||
 				    !(pvmw->flags & PVMW_MIGRATION))
 					return not_found(pvmw);
-				entry = pmd_to_swp_entry(pmde);
-				if (!is_migration_entry(entry) ||
-				    !check_pmd(swp_offset_pfn(entry), pvmw))
+				entry = softleaf_from_pmd(pmde);
+
+				if (!softleaf_is_migration(entry) ||
+				    !check_pmd(softleaf_to_pfn(entry), pvmw))
 					return not_found(pvmw);
 				return true;
 			}
-			if (likely(pmd_trans_huge(pmde) || pmd_devmap(pmde))) {
+			if (likely(pmd_trans_huge(pmde))) {
 				if (pvmw->flags & PVMW_MIGRATION)
 					return not_found(pvmw);
 				if (!check_pmd(pmd_pfn(pmde), pvmw))
@@ -265,8 +274,16 @@ restart:
 			 * cannot return prematurely, while zap_huge_pmd() has
 			 * cleared *pmd but not decremented compound_mapcount().
 			 */
+			const softleaf_t entry = softleaf_from_pmd(pmde);
+
+			if (softleaf_is_device_private(entry)) {
+				pvmw->ptl = pmd_lock(mm, pvmw->pmd);
+				return true;
+			}
+
 			if ((pvmw->flags & PVMW_SYNC) &&
-			    transhuge_vma_suitable(vma, pvmw->address) &&
+			    thp_vma_suitable_order(vma, pvmw->address,
+						   PMD_ORDER) &&
 			    (pvmw->nr_pages >= HPAGE_PMD_NR)) {
 				spinlock_t *ptl = pmd_lock(mm, pvmw->pmd);
 
@@ -275,13 +292,13 @@ 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;
 		}
 this_pte:
-		if (check_pte(pvmw))
+		if (check_pte(pvmw, 1))
 			return true;
 next_pte:
 		do {
@@ -296,14 +313,20 @@ next_pte:
 				}
 				pte_unmap(pvmw->pte);
 				pvmw->pte = NULL;
+				pvmw->flags |= PVMW_PGTABLE_CROSSED;
 				goto restart;
 			}
 			pvmw->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);
@@ -311,17 +334,21 @@ 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,
@@ -329,11 +356,13 @@ 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