+ lib-test_maple_tree-add-testing-for-maple-tree-fix.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: test_maple_tree: add null expansion tests
has been added to the -mm mm-unstable branch.  Its filename is
     lib-test_maple_tree-add-testing-for-maple-tree-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-test_maple_tree-add-testing-for-maple-tree-fix.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Liam Howlett <liam.howlett@oracle.com>
Subject: test_maple_tree: add null expansion tests

Link: https://lkml.kernel.org/r/20220511144304.1430851-3-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/test_maple_tree.c |   55 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

--- a/lib/test_maple_tree.c~lib-test_maple_tree-add-testing-for-maple-tree-fix
+++ a/lib/test_maple_tree.c
@@ -35537,6 +35537,57 @@ static noinline void check_root_expand(s
 	mas_unlock(&mas);
 }
 
+static noinline void check_null_expand(struct maple_tree *mt)
+{
+	unsigned long i, max = 100;
+	unsigned char data_end;
+	MA_STATE(mas, mt, 959, 959);
+
+	for (i = 0; i <= max; i++)
+		mtree_test_store_range(mt, i * 10, i * 10 + 5, &i);
+	/* Test expanding null at start. */
+	mas_walk(&mas);
+	data_end = mas_data_end(&mas);
+	mas_set_range(&mas, 959, 963);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, mtree_load(mt, 963) != NULL);
+	MT_BUG_ON(mt, data_end != mas_data_end(&mas));
+
+	/* Test expanding null at end. */
+	mas_set(&mas, 880);
+	mas_walk(&mas);
+	data_end = mas_data_end(&mas);
+	mas_set_range(&mas, 884, 887);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, mtree_load(mt, 884) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 889) != NULL);
+	MT_BUG_ON(mt, data_end != mas_data_end(&mas));
+
+	/* Test expanding null at start and end. */
+	mas_set(&mas, 890);
+	mas_walk(&mas);
+	data_end = mas_data_end(&mas);
+	mas_set_range(&mas, 900, 905);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, mtree_load(mt, 899) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 900) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 905) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 906) != NULL);
+	MT_BUG_ON(mt, data_end - 2 != mas_data_end(&mas));
+
+	/* Test expanding null across multiple slots. */
+	mas_set(&mas, 800);
+	mas_walk(&mas);
+	data_end = mas_data_end(&mas);
+	mas_set_range(&mas, 810, 825);
+	mas_store_gfp(&mas, NULL, GFP_KERNEL);
+	MT_BUG_ON(mt, mtree_load(mt, 809) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 810) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 825) != NULL);
+	MT_BUG_ON(mt, mtree_load(mt, 826) != NULL);
+	MT_BUG_ON(mt, data_end - 4 != mas_data_end(&mas));
+}
+
 static noinline void check_gap_combining(struct maple_tree *mt)
 {
 	struct maple_enode *mn1, *mn2;
@@ -37627,6 +37678,10 @@ static int maple_tree_seed(void)
 	check_new_node(&tree);
 	mtree_destroy(&tree);
 
+	mt_init_flags(&tree, MT_FLAGS_ALLOC_RANGE);
+	check_null_expand(&tree);
+	mtree_destroy(&tree);
+
 	mt_init_flags(&tree, 0);
 	check_dfs_preorder(&tree);
 	mtree_destroy(&tree);
_

Patches currently in -mm which might be from liam.howlett@oracle.com are

maple-tree-add-new-data-structure-fix.patch
lib-test_maple_tree-add-testing-for-maple-tree-fix.patch