From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Fri, 20 Nov 2020 03:43:40 +0000 (-0500)
Subject: maple_tree: Fix __mas_next() when the limit is hit
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=6d0d9e23b9a979c75d518e35cb399c4cf39db05c;p=users%2Fjedix%2Flinux-maple.git

maple_tree: Fix __mas_next() when the limit is hit

When a search limit is hit, restore the previous location so that
mas_next() works on that particular ma_state.

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

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 63d4bc2e00c1..ab207b44afed 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -3725,7 +3725,8 @@ static inline void *__mas_next(struct ma_state *mas, unsigned long limit,
 		unsigned long *range_start)
 {
 	void *entry = NULL;
-	struct maple_enode *prev_node;
+	struct maple_enode *prev_node = mas->node;
+	unsigned char offset = mas->offset;
 	unsigned long index = mas->index;
 	enum maple_type mt = mte_node_type(mas->node);
 
@@ -3749,10 +3750,15 @@ retry:
 		if (mas_next_nentry(mas, limit, range_start))
 			break;
 
-		if (*range_start > limit)
+		if (*range_start > limit) {
+			mas->offset = offset;
+			mas->node = prev_node;
 			return NULL;
+		}
 
 next_node:
+		prev_node = mas->node;
+		offset = mas->offset;
 		mas_next_node(mas, limit);
 		mas->offset = 0;
 		mt = mte_node_type(mas->node);