Merge branch 'char-misc-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc into fpga-dfl-for-5.4

1 files changed, 77 insertions, 57 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index f48693f75b37..65e0874fce17 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -403,7 +403,7 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
 	},
 };
 
-static void migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_page_add(struct page *page, struct list_head *pagelist,
 				unsigned long flags);
 
 struct queue_pages {
@@ -429,11 +429,14 @@ static inline bool queue_pages_required(struct page *page,
 }
 
 /*
- * queue_pages_pmd() has three possible return values:
- * 1 - pages are placed on the right node or queued successfully.
- * 0 - THP was split.
- * -EIO - is migration entry or MPOL_MF_STRICT was specified and an existing
- *        page was already on a node that does not follow the policy.
+ * queue_pages_pmd() has four possible return values:
+ * 0 - pages are placed on the right node or queued successfully.
+ * 1 - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were
+ *     specified.
+ * 2 - THP was split.
+ * -EIO - is migration entry or only MPOL_MF_STRICT was specified and an
+ *        existing page was already on a node that does not follow the
+ *        policy.
  */
 static int queue_pages_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr,
 				unsigned long end, struct mm_walk *walk)
@@ -451,23 +454,20 @@ static int queue_pages_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr,
 	if (is_huge_zero_page(page)) {
 		spin_unlock(ptl);
 		__split_huge_pmd(walk->vma, pmd, addr, false, NULL);
+		ret = 2;
 		goto out;
 	}
-	if (!queue_pages_required(page, qp)) {
-		ret = 1;
+	if (!queue_pages_required(page, qp))
 		goto unlock;
-	}
 
-	ret = 1;
 	flags = qp->flags;
 	/* go to thp migration */
 	if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
-		if (!vma_migratable(walk->vma)) {
-			ret = -EIO;
+		if (!vma_migratable(walk->vma) ||
+		    migrate_page_add(page, qp->pagelist, flags)) {
+			ret = 1;
 			goto unlock;
 		}
-
-		migrate_page_add(page, qp->pagelist, flags);
 	} else
 		ret = -EIO;
 unlock:
@@ -479,6 +479,13 @@ out:
 /*
  * Scan through pages checking if pages follow certain conditions,
  * and move them to the pagelist if they do.
+ *
+ * queue_pages_pte_range() has three possible return values:
+ * 0 - pages are placed on the right node or queued successfully.
+ * 1 - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were
+ *     specified.
+ * -EIO - only MPOL_MF_STRICT was specified and an existing page was already
+ *        on a node that does not follow the policy.
  */
 static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
 			unsigned long end, struct mm_walk *walk)
@@ -488,17 +495,17 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
 	struct queue_pages *qp = walk->private;
 	unsigned long flags = qp->flags;
 	int ret;
+	bool has_unmovable = false;
 	pte_t *pte;
 	spinlock_t *ptl;
 
 	ptl = pmd_trans_huge_lock(pmd, vma);
 	if (ptl) {
 		ret = queue_pages_pmd(pmd, ptl, addr, end, walk);
-		if (ret > 0)
-			return 0;
-		else if (ret < 0)
+		if (ret != 2)
 			return ret;
 	}
+	/* THP was split, fall through to pte walk */
 
 	if (pmd_trans_unstable(pmd))
 		return 0;
@@ -519,14 +526,28 @@ static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr,
 		if (!queue_pages_required(page, qp))
 			continue;
 		if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
-			if (!vma_migratable(vma))
+			/* MPOL_MF_STRICT must be specified if we get here */
+			if (!vma_migratable(vma)) {
+				has_unmovable = true;
 				break;
-			migrate_page_add(page, qp->pagelist, flags);
+			}
+
+			/*
+			 * Do not abort immediately since there may be
+			 * temporary off LRU pages in the range.  Still
+			 * need migrate other LRU pages.
+			 */
+			if (migrate_page_add(page, qp->pagelist, flags))
+				has_unmovable = true;
 		} else
 			break;
 	}
 	pte_unmap_unlock(pte - 1, ptl);
 	cond_resched();
+
+	if (has_unmovable)
+		return 1;
+
 	return addr != end ? -EIO : 0;
 }
 
@@ -639,7 +660,13 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end,
  *
  * If pages found in a given range are on a set of nodes (determined by
  * @nodes and @flags,) it's isolated and queued to the pagelist which is
- * passed via @private.)
+ * passed via @private.
+ *
+ * queue_pages_range() has three possible return values:
+ * 1 - there is unmovable page, but MPOL_MF_MOVE* & MPOL_MF_STRICT were
+ *     specified.
+ * 0 - queue pages successfully or no misplaced page.
+ * -EIO - there is misplaced page and only MPOL_MF_STRICT was specified.
  */
 static int
 queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end,
@@ -940,7 +967,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 /*
  * page migration, thp tail pages can be passed.
  */
-static void migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_page_add(struct page *page, struct list_head *pagelist,
 				unsigned long flags)
 {
 	struct page *head = compound_head(page);
@@ -953,8 +980,19 @@ static void migrate_page_add(struct page *page, struct list_head *pagelist,
 			mod_node_page_state(page_pgdat(head),
 				NR_ISOLATED_ANON + page_is_file_cache(head),
 				hpage_nr_pages(head));
+		} else if (flags & MPOL_MF_STRICT) {
+			/*
+			 * Non-movable page may reach here.  And, there may be
+			 * temporary off LRU pages or non-LRU movable pages.
+			 * Treat them as unmovable pages since they can't be
+			 * isolated, so they can't be moved at the moment.  It
+			 * should return -EIO for this case too.
+			 */
+			return -EIO;
 		}
 	}
+
+	return 0;
 }
 
 /* page allocation callback for NUMA node migration */
@@ -1142,8 +1180,8 @@ static struct page *new_page(struct page *page, unsigned long start)
 	} else if (PageTransHuge(page)) {
 		struct page *thp;
 
-		thp = alloc_hugepage_vma(GFP_TRANSHUGE, vma, address,
-					 HPAGE_PMD_ORDER);
+		thp = alloc_pages_vma(GFP_TRANSHUGE, HPAGE_PMD_ORDER, vma,
+				address, numa_node_id());
 		if (!thp)
 			return NULL;
 		prep_transhuge_page(thp);
@@ -1157,9 +1195,10 @@ static struct page *new_page(struct page *page, unsigned long start)
 }
 #else
 
-static void migrate_page_add(struct page *page, struct list_head *pagelist,
+static int migrate_page_add(struct page *page, struct list_head *pagelist,
 				unsigned long flags)
 {
+	return -EIO;
 }
 
 int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from,
@@ -1182,6 +1221,7 @@ static long do_mbind(unsigned long start, unsigned long len,
 	struct mempolicy *new;
 	unsigned long end;
 	int err;
+	int ret;
 	LIST_HEAD(pagelist);
 
 	if (flags & ~(unsigned long)MPOL_MF_VALID)
@@ -1243,10 +1283,15 @@ static long do_mbind(unsigned long start, unsigned long len,
 	if (err)
 		goto mpol_out;
 
-	err = queue_pages_range(mm, start, end, nmask,
+	ret = queue_pages_range(mm, start, end, nmask,
 			  flags | MPOL_MF_INVERT, &pagelist);
-	if (!err)
-		err = mbind_range(mm, start, end, new);
+
+	if (ret < 0) {
+		err = -EIO;
+		goto up_out;
+	}
+
+	err = mbind_range(mm, start, end, new);
 
 	if (!err) {
 		int nr_failed = 0;
@@ -1259,13 +1304,14 @@ static long do_mbind(unsigned long start, unsigned long len,
 				putback_movable_pages(&pagelist);
 		}
 
-		if (nr_failed && (flags & MPOL_MF_STRICT))
+		if ((ret > 0) || (nr_failed && (flags & MPOL_MF_STRICT)))
 			err = -EIO;
 	} else
 		putback_movable_pages(&pagelist);
 
+up_out:
 	up_write(&mm->mmap_sem);
- mpol_out:
+mpol_out:
 	mpol_put(new);
 	return err;
 }
@@ -1688,7 +1734,7 @@ struct mempolicy *__get_vma_policy(struct vm_area_struct *vma,
  * freeing by another task.  It is the caller's responsibility to free the
  * extra reference for shared policies.
  */
-static struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
+struct mempolicy *get_vma_policy(struct vm_area_struct *vma,
 						unsigned long addr)
 {
 	struct mempolicy *pol = __get_vma_policy(vma, addr);
@@ -2037,7 +2083,6 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
  * 	@vma:  Pointer to VMA or NULL if not available.
  *	@addr: Virtual Address of the allocation. Must be inside the VMA.
  *	@node: Which node to prefer for allocation (modulo policy).
- *	@hugepage: for hugepages try only the preferred node if possible
  *
  * 	This function allocates a page from the kernel page pool and applies
  *	a NUMA policy associated with the VMA or the current process.
@@ -2048,7 +2093,7 @@ static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
  */
 struct page *
 alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma,
-		unsigned long addr, int node, bool hugepage)
+		unsigned long addr, int node)
 {
 	struct mempolicy *pol;
 	struct page *page;
@@ -2066,31 +2111,6 @@ alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma,
 		goto out;
 	}
 
-	if (unlikely(IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hugepage)) {
-		int hpage_node = node;
-
-		/*
-		 * For hugepage allocation and non-interleave policy which
-		 * allows the current node (or other explicitly preferred
-		 * node) we only try to allocate from the current/preferred
-		 * node and don't fall back to other nodes, as the cost of
-		 * remote accesses would likely offset THP benefits.
-		 *
-		 * If the policy is interleave, or does not allow the current
-		 * node in its nodemask, we allocate the standard way.
-		 */
-		if (pol->mode == MPOL_PREFERRED && !(pol->flags & MPOL_F_LOCAL))
-			hpage_node = pol->v.preferred_node;
-
-		nmask = policy_nodemask(gfp, pol);
-		if (!nmask || node_isset(hpage_node, *nmask)) {
-			mpol_cond_put(pol);
-			page = __alloc_pages_node(hpage_node,
-						gfp | __GFP_THISNODE, order);
-			goto out;
-		}
-	}
-
 	nmask = policy_nodemask(gfp, pol);
 	preferred_nid = policy_node(gfp, pol, node);
 	page = __alloc_pages_nodemask(gfp, order, preferred_nid, nmask);