sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes

1 files changed, 24 insertions, 23 deletions

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 5577e6da6fe3..4a6ecdb12a92 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -4965,7 +4965,8 @@ not_found:
  * Return: True if found in a leaf, false otherwise.
  *
  */
-static bool mas_rev_awalk(struct ma_state *mas, unsigned long size)
+static bool mas_rev_awalk(struct ma_state *mas, unsigned long size,
+		unsigned long *gap_min, unsigned long *gap_max)
 {
 	enum maple_type type = mte_node_type(mas->node);
 	struct maple_node *node = mas_mn(mas);
@@ -5030,8 +5031,8 @@ static bool mas_rev_awalk(struct ma_state *mas, unsigned long size)
 
 	if (unlikely(ma_is_leaf(type))) {
 		mas->offset = offset;
-		mas->min = min;
-		mas->max = min + gap - 1;
+		*gap_min = min;
+		*gap_max = min + gap - 1;
 		return true;
 	}
 
@@ -5055,10 +5056,10 @@ static inline bool mas_anode_descend(struct ma_state *mas, unsigned long size)
 {
 	enum maple_type type = mte_node_type(mas->node);
 	unsigned long pivot, min, gap = 0;
-	unsigned char offset;
-	unsigned long *gaps;
-	unsigned long *pivots = ma_pivots(mas_mn(mas), type);
-	void __rcu **slots = ma_slots(mas_mn(mas), type);
+	unsigned char offset, data_end;
+	unsigned long *gaps, *pivots;
+	void __rcu **slots;
+	struct maple_node *node;
 	bool found = false;
 
 	if (ma_is_dense(type)) {
@@ -5066,13 +5067,15 @@ static inline bool mas_anode_descend(struct ma_state *mas, unsigned long size)
 		return true;
 	}
 
-	gaps = ma_gaps(mte_to_node(mas->node), type);
+	node = mas_mn(mas);
+	pivots = ma_pivots(node, type);
+	slots = ma_slots(node, type);
+	gaps = ma_gaps(node, type);
 	offset = mas->offset;
 	min = mas_safe_min(mas, pivots, offset);
-	for (; offset < mt_slots[type]; offset++) {
-		pivot = mas_safe_pivot(mas, pivots, offset, type);
-		if (offset && !pivot)
-			break;
+	data_end = ma_data_end(node, type, pivots, mas->max);
+	for (; offset <= data_end; offset++) {
+		pivot = mas_logical_pivot(mas, pivots, offset, type);
 
 		/* Not within lower bounds */
 		if (mas->index > pivot)
@@ -5307,6 +5310,9 @@ int mas_empty_area(struct ma_state *mas, unsigned long min,
 	unsigned long *pivots;
 	enum maple_type mt;
 
+	if (min >= max)
+		return -EINVAL;
+
 	if (mas_is_start(mas))
 		mas_start(mas);
 	else if (mas->offset >= 2)
@@ -5361,6 +5367,9 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 {
 	struct maple_enode *last = mas->node;
 
+	if (min >= max)
+		return -EINVAL;
+
 	if (mas_is_start(mas)) {
 		mas_start(mas);
 		mas->offset = mas_data_end(mas);
@@ -5380,7 +5389,7 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 	mas->index = min;
 	mas->last = max;
 
-	while (!mas_rev_awalk(mas, size)) {
+	while (!mas_rev_awalk(mas, size, &min, &max)) {
 		if (last == mas->node) {
 			if (!mas_rewind_node(mas))
 				return -EBUSY;
@@ -5395,17 +5404,9 @@ int mas_empty_area_rev(struct ma_state *mas, unsigned long min,
 	if (unlikely(mas->offset == MAPLE_NODE_SLOTS))
 		return -EBUSY;
 
-	/*
-	 * mas_rev_awalk() has set mas->min and mas->max to the gap values.  If
-	 * the maximum is outside the window we are searching, then use the last
-	 * location in the search.
-	 * mas->max and mas->min is the range of the gap.
-	 * mas->index and mas->last are currently set to the search range.
-	 */
-
 	/* Trim the upper limit to the max. */
-	if (mas->max <= mas->last)
-		mas->last = mas->max;
+	if (max <= mas->last)
+		mas->last = max;
 
 	mas->index = mas->last - size + 1;
 	return 0;