From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Mon, 28 Sep 2020 19:18:45 +0000 (-0400)
Subject: maple_tree: Add mas_node_cnt() to allocate enough nodes in a mas
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=f2d143376bd35a1c38324672d4cfc8a614e7c326;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Add mas_node_cnt() to allocate enough nodes in a mas

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 5d6c69aae610..e010b7881893 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -977,6 +977,20 @@ static inline struct maple_node *mas_node_cnt(struct ma_state *mas, int count)
 	return mas->alloc;
 }
 
+int mas_entry_cnt(struct ma_state *mas, unsigned long nr_entries) {
+	int nonleaf_cap = MAPLE_ARANGE64_SLOTS - 1;
+	int nr_leaves;
+
+	if (!mt_is_alloc(mas->tree))
+	    nonleaf_cap = MAPLE_RANGE64_SLOTS - 1;
+
+	nr_leaves = DIV_ROUND_UP(nr_entries, MAPLE_RANGE64_SLOTS);
+	mas_node_cnt(mas, nr_leaves +  DIV_ROUND_UP(nr_leaves, nonleaf_cap));
+	if (!mas_is_err(mas))
+		return 0;
+	return xa_err(mas->node);
+
+}
 /*
  * Sets up maple state for operations by setting mas->min = 0 & mas->node to
  * certain values.