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From:   "Liam R. Howlett" <Liam.Howlett@oracle.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        maple-tree@lists.infradead.org,
        "Liam R. Howlett" <Liam.Howlett@oracle.com>
Subject: [PATCH 14/34] maple_tree: Use MAS_BUG_ON() prior to calling mas_meta_gap()
Date:   Tue, 25 Apr 2023 10:09:35 -0400
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Replace the call to BUG_ON() in mas_meta_gap() with calls before the
function call MAS_BUG_ON() to get more information on error condition.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
---
 lib/maple_tree.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 28853ed23fe8a..41873d935cfa3 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -963,8 +963,6 @@ static inline unsigned char ma_meta_end(struct maple_node *mn,
 static inline unsigned char ma_meta_gap(struct maple_node *mn,
 					enum maple_type mt)
 {
-	BUG_ON(mt != maple_arange_64);
-
 	return mn->ma64.meta.gap;
 }
 
@@ -1629,6 +1627,7 @@ static inline unsigned long mas_max_gap(struct ma_state *mas)
 		return mas_leaf_max_gap(mas);
 
 	node = mas_mn(mas);
+	MAS_BUG_ON(mas, mt != maple_arange_64);
 	offset = ma_meta_gap(node, mt);
 	if (offset == MAPLE_ARANGE64_META_MAX)
 		return 0;
@@ -1662,6 +1661,7 @@ static inline void mas_parent_gap(struct ma_state *mas, unsigned char offset,
 	pgaps = ma_gaps(pnode, pmt);
 
 ascend:
+	MAS_BUG_ON(mas, pmt != maple_arange_64);
 	meta_offset = ma_meta_gap(pnode, pmt);
 	if (meta_offset == MAPLE_ARANGE64_META_MAX)
 		meta_gap = 0;
-- 
2.39.2