From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Wed, 2 Mar 2022 02:35:31 +0000 (-0500)
Subject: maple_tree: Fix spanning store to a single root node
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4010ab32a99c2c42681f303ca863ccb9caaeab66;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Fix spanning store to a single root node

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index b2defca4a0b9..521d1e63d77c 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -2678,9 +2678,12 @@ static inline void mast_cp_to_nodes(struct maple_subtree_state *mast,
 	mast->r->node = mte_node_or_none(right);
 
 	mast->l->min = mast->orig_l->min;
-	mast->l->max = mast->bn->pivot[split];
 	mab_mas_cp(mast->bn, 0, split, mast->l, true);
 	mast->r->max = mast->l->max;
+	if (split == mast->bn->b_end) {
+		mast->l->max = mast->orig_r->max;
+		return;
+	}
 
 	if (middle) {
 		mab_mas_cp(mast->bn, 1 + split, mid_split, mast->m, true);
@@ -2941,11 +2944,12 @@ static int mas_spanning_rebalance(struct ma_state *mas,
 	if (right)
 		mte_set_parent(right, l_mas.node, ++slot);
 
+	if (mas_is_root_limits(mast->l)) {
 new_root:
-	if (mas_is_root_limits(mast->l))
 		mast_new_root(mast, mas);
-	else
+	} else {
 		mas_mn(&l_mas)->parent = mas_mn(mast->orig_l)->parent;
+	}
 
 	if (!mte_dead_node(mast->orig_l->node))
 		mat_add(&free, mast->orig_l->node);