From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Wed, 9 Dec 2020 22:01:03 +0000 (-0500)
Subject: maple_tree: Rework mas_destroy_rebalance()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=32d79c63cea1205bb6552393726abe5f6afce94a;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Rework mas_destroy_rebalance()

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index ee01dc762fcd..515c0ac41517 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -2502,7 +2502,7 @@ static inline void mas_destroy_rebalance(struct ma_state *mas,
 					 unsigned char mas_end)
 {
 	enum maple_type mt = mte_node_type(mas->node);
-	struct maple_node reuse, *newnode, *parent, *new_left;
+	struct maple_node reuse, *newnode, *parent, *new_left, *left, *node;
 	struct maple_enode *eparent;
 	unsigned char offset, tmp, split = mt_slots[mt] / 2;
 	void **l_slots, **slots;
@@ -2521,19 +2521,20 @@ static inline void mas_destroy_rebalance(struct ma_state *mas,
 
 		newnode = mas_pop_node(mas);
 	} else {
-		memset(&reuse, 0, sizeof(struct maple_node));
 		newnode = &reuse;
 	}
 
-	newnode->parent = mas_mn(mas)->parent;
+	node = mas_mn(mas);
+	newnode->parent = node->parent;
 	pivs = ma_pivots(newnode, mt);
 
 
 
 	slots = ma_slots(newnode, mt);
 	pivs = ma_pivots(newnode, mt);
-	l_slots = ma_slots(mas_mn(&l_mas), mt);
-	l_pivs = ma_pivots(mas_mn(&l_mas), mt);
+	left = mas_mn(&l_mas);
+	l_slots = ma_slots(left, mt);
+	l_pivs = ma_pivots(left, mt);
 	if (!l_slots[split])
 		split++;
 	tmp = mas_data_end(&l_mas) - split;
@@ -2541,16 +2542,23 @@ static inline void mas_destroy_rebalance(struct ma_state *mas,
 	memcpy(slots, l_slots + split + 1, sizeof(void *) * tmp);
 	memcpy(pivs, l_pivs + split + 1, sizeof(unsigned long) * tmp);
 	pivs[tmp] = l_mas.max;
-	memcpy(slots + tmp, ma_slots(mas_mn(mas), mt), sizeof(void *) * mas_end);
-	memcpy(pivs + tmp, ma_pivots(mas_mn(mas), mt), sizeof(unsigned long) * mas_end);
+	memcpy(slots + tmp, ma_slots(node, mt), sizeof(void *) * mas_end);
+	memcpy(pivs + tmp, ma_pivots(node, mt), sizeof(unsigned long) * mas_end);
 
 	l_mas.max = l_pivs[split];
 	mas->min = l_mas.max + 1;
 	eparent = mt_mk_node(mte_parent(l_mas.node),
 			     mas_parent_enum(&l_mas, l_mas.node));
 	if (!mt_in_rcu(mas->tree)) {
-
-		memcpy(mas_mn(mas), newnode, sizeof(struct maple_node));
+		tmp += mas_end - 1;
+		if (tmp < mt_pivots[mt])
+			memset(pivs + tmp, 0,
+			      sizeof (unsigned long *) * (mt_pivots[mt] - tmp));
+		if (tmp < mt_slots[mt])
+			memset(slots + tmp, 0,
+			      sizeof (void *) * (mt_pivots[mt] - tmp));
+
+		memcpy(node, newnode, sizeof(struct maple_node));
 		mte_set_pivot(eparent, mte_parent_slot(l_mas.node),
 			      l_pivs[split]);
 		// Remove data from l_pivs.
@@ -2569,7 +2577,7 @@ static inline void mas_destroy_rebalance(struct ma_state *mas,
 
 	// replace l_mas
 	new_left = mas_pop_node(mas);
-	new_left->parent = mas_mn(&l_mas)->parent;
+	new_left->parent = left->parent;
 	mt = mte_node_type(l_mas.node);
 	slots = ma_slots(new_left, mt);
 	pivs = ma_pivots(new_left, mt);