From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Thu, 3 Mar 2022 15:47:07 +0000 (-0500)
Subject: Fix clearing of implied pivot at end of node in node reuse
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=af169139a3fbb61a4d2ca51a52faea88d7e01c8e;p=users%2Fjedix%2Flinux-maple.git

Fix clearing of implied pivot at end of node in node reuse

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index f1fdb441ead7..bb7fa9727378 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -2116,8 +2116,7 @@ static inline unsigned char mas_store_b_node(struct ma_wr_state *wr_mas,
 
 	/* Copy end data to the end of the node. */
 	mas_mab_cp(mas, slot, wr_mas->node_end + 1, b_node, ++b_end);
-	b_end = b_node->b_end - 1;
-	return b_end;
+	return b_node->b_end - 1;
 }
 
 /*
@@ -3429,27 +3428,25 @@ static int mas_split(struct ma_state *mas, struct maple_big_node *b_node)
  *
  * Return: True if node was reused, false otherwise.
  */
-static inline bool mas_reuse_node(struct ma_state *mas,
+static inline bool mas_reuse_node(struct ma_wr_state *wr_mas,
 			  struct maple_big_node *bn, unsigned char end)
 {
 	/* Need to be rcu safe. */
-	if (mt_in_rcu(mas->tree))
+	if (mt_in_rcu(wr_mas->mas->tree))
 		return false;
 
-	mab_mas_cp(bn, 0, bn->b_end, mas, false);
-
+	mab_mas_cp(bn, 0, bn->b_end, wr_mas->mas, false);
 	if (end > bn->b_end) {
-		/* Zero end of node. */
-		enum maple_type mt = mte_node_type(mas->node);
-		struct maple_node *mn = mas_mn(mas);
-		unsigned long *pivots = ma_pivots(mn, mt);
-		void __rcu **slots = ma_slots(mn, mt);
-		char clear = mt_slots[mt] - bn->b_end - 2;
+		char clear = mt_slots[wr_mas->type] - bn->b_end - 2;
 
+		if (bn->pivot[bn->b_end] != wr_mas->mas->max)
+			clear++;
+
+		/* Zero end of node. */
 		if (clear > 0) {
-			memset(slots + bn->b_end + 1, 0,
+			memset(wr_mas->slots + bn->b_end+1, 0,
 			       sizeof(void *) * clear);
-			memset(pivots + bn->b_end + 1, 0,
+			memset(wr_mas->pivots + bn->b_end+1, 0,
 			       sizeof(unsigned long *) * clear);
 		}
 	}
@@ -3463,7 +3460,7 @@ static inline bool mas_reuse_node(struct ma_state *mas,
  * @b_node: The maple big node
  * @end: The end of the data.
  */
-static inline int mas_commit_b_node(struct ma_state *mas,
+static inline int mas_commit_b_node(struct ma_wr_state *wr_mas,
 			    struct maple_big_node *b_node, unsigned char end)
 {
 	struct maple_node *node;
@@ -3471,27 +3468,28 @@ static inline int mas_commit_b_node(struct ma_state *mas,
 	enum maple_type b_type = b_node->type;
 
 	if ((b_end < mt_min_slots[b_type]) &&
-	    (!mte_is_root(mas->node)) && (mas_mt_height(mas) > 1))
-		return mas_rebalance(mas, b_node);
+	    (!mte_is_root(wr_mas->mas->node)) &&
+	    (mas_mt_height(wr_mas->mas) > 1))
+		return mas_rebalance(wr_mas->mas, b_node);
 
 	if (b_end >= mt_slots[b_type])
-		return mas_split(mas, b_node);
+		return mas_split(wr_mas->mas, b_node);
 
-	if (mas_reuse_node(mas, b_node, end))
+	if (mas_reuse_node(wr_mas, b_node, end))
 		goto reuse_node;
 
-	mas_node_count(mas, 1);
-	if (mas_is_err(mas))
+	mas_node_count(wr_mas->mas, 1);
+	if (mas_is_err(wr_mas->mas))
 		return 0;
 
-	node = mas_pop_node(mas);
-	node->parent = mas_mn(mas)->parent;
-	mas->node = mt_mk_node(node, b_type);
-	mab_mas_cp(b_node, 0, b_end, mas, true);
+	node = mas_pop_node(wr_mas->mas);
+	node->parent = mas_mn(wr_mas->mas)->parent;
+	wr_mas->mas->node = mt_mk_node(node, b_type);
+	mab_mas_cp(b_node, 0, b_end, wr_mas->mas, true);
 
-	mas_replace(mas, false);
+	mas_replace(wr_mas->mas, false);
 reuse_node:
-	mas_update_gap(mas);
+	mas_update_gap(wr_mas->mas);
 	return 1;
 }
 
@@ -4227,7 +4225,7 @@ slow_path:
 	       sizeof(unsigned long) * zero);
 
 	trace_ma_write(__func__, mas, 0, wr_mas->entry);
-	mas_commit_b_node(mas, &b_node, wr_mas->node_end);
+	mas_commit_b_node(wr_mas, &b_node, wr_mas->node_end);
 }
 
 /*