1 /*
2  * multiorder.c: Multi-order radix tree entry testing
3  * Copyright (c) 2016 Intel Corporation
4  * Author: Ross Zwisler <ross.zwisler@linux.intel.com>
5  * Author: Matthew Wilcox <matthew.r.wilcox@intel.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  */
16 #include <linux/radix-tree.h>
17 #include <linux/slab.h>
18 #include <linux/errno.h>
19 
20 #include "test.h"
21 
22 #define for_each_index(i, base, order) \
23 	for (i = base; i < base + (1 << order); i++)
24 
25 static void __multiorder_tag_test(int index, int order)
26 {
27 	RADIX_TREE(tree, GFP_KERNEL);
28 	int base, err, i;
29 
30 	/* our canonical entry */
31 	base = index & ~((1 << order) - 1);
32 
33 	printf("Multiorder tag test with index %d, canonical entry %d\n",
34 			index, base);
35 
36 	err = item_insert_order(&tree, index, order);
37 	assert(!err);
38 
39 	/*
40 	 * Verify we get collisions for covered indices.  We try and fail to
41 	 * insert an exceptional entry so we don't leak memory via
42 	 * item_insert_order().
43 	 */
44 	for_each_index(i, base, order) {
45 		err = __radix_tree_insert(&tree, i, order,
46 				(void *)(0xA0 | RADIX_TREE_EXCEPTIONAL_ENTRY));
47 		assert(err == -EEXIST);
48 	}
49 
50 	for_each_index(i, base, order) {
51 		assert(!radix_tree_tag_get(&tree, i, 0));
52 		assert(!radix_tree_tag_get(&tree, i, 1));
53 	}
54 
55 	assert(radix_tree_tag_set(&tree, index, 0));
56 
57 	for_each_index(i, base, order) {
58 		assert(radix_tree_tag_get(&tree, i, 0));
59 		assert(!radix_tree_tag_get(&tree, i, 1));
60 	}
61 
62 	assert(radix_tree_tag_clear(&tree, index, 0));
63 
64 	for_each_index(i, base, order) {
65 		assert(!radix_tree_tag_get(&tree, i, 0));
66 		assert(!radix_tree_tag_get(&tree, i, 1));
67 	}
68 
69 	assert(!radix_tree_tagged(&tree, 0));
70 	assert(!radix_tree_tagged(&tree, 1));
71 
72 	item_kill_tree(&tree);
73 }
74 
75 static void multiorder_tag_tests(void)
76 {
77 	/* test multi-order entry for indices 0-7 with no sibling pointers */
78 	__multiorder_tag_test(0, 3);
79 	__multiorder_tag_test(5, 3);
80 
81 	/* test multi-order entry for indices 8-15 with no sibling pointers */
82 	__multiorder_tag_test(8, 3);
83 	__multiorder_tag_test(15, 3);
84 
85 	/*
86 	 * Our order 5 entry covers indices 0-31 in a tree with height=2.
87 	 * This is broken up as follows:
88 	 * 0-7:		canonical entry
89 	 * 8-15:	sibling 1
90 	 * 16-23:	sibling 2
91 	 * 24-31:	sibling 3
92 	 */
93 	__multiorder_tag_test(0, 5);
94 	__multiorder_tag_test(29, 5);
95 
96 	/* same test, but with indices 32-63 */
97 	__multiorder_tag_test(32, 5);
98 	__multiorder_tag_test(44, 5);
99 
100 	/*
101 	 * Our order 8 entry covers indices 0-255 in a tree with height=3.
102 	 * This is broken up as follows:
103 	 * 0-63:	canonical entry
104 	 * 64-127:	sibling 1
105 	 * 128-191:	sibling 2
106 	 * 192-255:	sibling 3
107 	 */
108 	__multiorder_tag_test(0, 8);
109 	__multiorder_tag_test(190, 8);
110 
111 	/* same test, but with indices 256-511 */
112 	__multiorder_tag_test(256, 8);
113 	__multiorder_tag_test(300, 8);
114 
115 	__multiorder_tag_test(0x12345678UL, 8);
116 }
117 
118 static void multiorder_check(unsigned long index, int order)
119 {
120 	unsigned long i;
121 	unsigned long min = index & ~((1UL << order) - 1);
122 	unsigned long max = min + (1UL << order);
123 	RADIX_TREE(tree, GFP_KERNEL);
124 
125 	printf("Multiorder index %ld, order %d\n", index, order);
126 
127 	assert(item_insert_order(&tree, index, order) == 0);
128 
129 	for (i = min; i < max; i++) {
130 		struct item *item = item_lookup(&tree, i);
131 		assert(item != 0);
132 		assert(item->index == index);
133 	}
134 	for (i = 0; i < min; i++)
135 		item_check_absent(&tree, i);
136 	for (i = max; i < 2*max; i++)
137 		item_check_absent(&tree, i);
138 	for (i = min; i < max; i++) {
139 		static void *entry = (void *)
140 					(0xA0 | RADIX_TREE_EXCEPTIONAL_ENTRY);
141 		assert(radix_tree_insert(&tree, i, entry) == -EEXIST);
142 	}
143 
144 	assert(item_delete(&tree, index) != 0);
145 
146 	for (i = 0; i < 2*max; i++)
147 		item_check_absent(&tree, i);
148 }
149 
150 static void multiorder_shrink(unsigned long index, int order)
151 {
152 	unsigned long i;
153 	unsigned long max = 1 << order;
154 	RADIX_TREE(tree, GFP_KERNEL);
155 	struct radix_tree_node *node;
156 
157 	printf("Multiorder shrink index %ld, order %d\n", index, order);
158 
159 	assert(item_insert_order(&tree, 0, order) == 0);
160 
161 	node = tree.rnode;
162 
163 	assert(item_insert(&tree, index) == 0);
164 	assert(node != tree.rnode);
165 
166 	assert(item_delete(&tree, index) != 0);
167 	assert(node == tree.rnode);
168 
169 	for (i = 0; i < max; i++) {
170 		struct item *item = item_lookup(&tree, i);
171 		assert(item != 0);
172 		assert(item->index == 0);
173 	}
174 	for (i = max; i < 2*max; i++)
175 		item_check_absent(&tree, i);
176 
177 	if (!item_delete(&tree, 0)) {
178 		printf("failed to delete index %ld (order %d)\n", index, order);		abort();
179 	}
180 
181 	for (i = 0; i < 2*max; i++)
182 		item_check_absent(&tree, i);
183 }
184 
185 static void multiorder_insert_bug(void)
186 {
187 	RADIX_TREE(tree, GFP_KERNEL);
188 
189 	item_insert(&tree, 0);
190 	radix_tree_tag_set(&tree, 0, 0);
191 	item_insert_order(&tree, 3 << 6, 6);
192 
193 	item_kill_tree(&tree);
194 }
195 
196 void multiorder_iteration(void)
197 {
198 	RADIX_TREE(tree, GFP_KERNEL);
199 	struct radix_tree_iter iter;
200 	void **slot;
201 	int i, err;
202 
203 	printf("Multiorder iteration test\n");
204 
205 #define NUM_ENTRIES 11
206 	int index[NUM_ENTRIES] = {0, 2, 4, 8, 16, 32, 34, 36, 64, 72, 128};
207 	int order[NUM_ENTRIES] = {1, 1, 2, 3,  4,  1,  0,  1,  3,  0, 7};
208 
209 	for (i = 0; i < NUM_ENTRIES; i++) {
210 		err = item_insert_order(&tree, index[i], order[i]);
211 		assert(!err);
212 	}
213 
214 	i = 0;
215 	/* start from index 1 to verify we find the multi-order entry at 0 */
216 	radix_tree_for_each_slot(slot, &tree, &iter, 1) {
217 		int height = order[i] / RADIX_TREE_MAP_SHIFT;
218 		int shift = height * RADIX_TREE_MAP_SHIFT;
219 
220 		assert(iter.index == index[i]);
221 		assert(iter.shift == shift);
222 		i++;
223 	}
224 
225 	/*
226 	 * Now iterate through the tree starting at an elevated multi-order
227 	 * entry, beginning at an index in the middle of the range.
228 	 */
229 	i = 8;
230 	radix_tree_for_each_slot(slot, &tree, &iter, 70) {
231 		int height = order[i] / RADIX_TREE_MAP_SHIFT;
232 		int shift = height * RADIX_TREE_MAP_SHIFT;
233 
234 		assert(iter.index == index[i]);
235 		assert(iter.shift == shift);
236 		i++;
237 	}
238 
239 	item_kill_tree(&tree);
240 }
241 
242 void multiorder_tagged_iteration(void)
243 {
244 	RADIX_TREE(tree, GFP_KERNEL);
245 	struct radix_tree_iter iter;
246 	void **slot;
247 	int i;
248 
249 	printf("Multiorder tagged iteration test\n");
250 
251 #define MT_NUM_ENTRIES 9
252 	int index[MT_NUM_ENTRIES] = {0, 2, 4, 16, 32, 40, 64, 72, 128};
253 	int order[MT_NUM_ENTRIES] = {1, 0, 2, 4,  3,  1,  3,  0,   7};
254 
255 #define TAG_ENTRIES 7
256 	int tag_index[TAG_ENTRIES] = {0, 4, 16, 40, 64, 72, 128};
257 
258 	for (i = 0; i < MT_NUM_ENTRIES; i++)
259 		assert(!item_insert_order(&tree, index[i], order[i]));
260 
261 	assert(!radix_tree_tagged(&tree, 1));
262 
263 	for (i = 0; i < TAG_ENTRIES; i++)
264 		assert(radix_tree_tag_set(&tree, tag_index[i], 1));
265 
266 	i = 0;
267 	/* start from index 1 to verify we find the multi-order entry at 0 */
268 	radix_tree_for_each_tagged(slot, &tree, &iter, 1, 1) {
269 		assert(iter.index == tag_index[i]);
270 		i++;
271 	}
272 
273 	/*
274 	 * Now iterate through the tree starting at an elevated multi-order
275 	 * entry, beginning at an index in the middle of the range.
276 	 */
277 	i = 4;
278 	radix_tree_for_each_slot(slot, &tree, &iter, 70) {
279 		assert(iter.index == tag_index[i]);
280 		i++;
281 	}
282 
283 	item_kill_tree(&tree);
284 }
285 
286 void multiorder_checks(void)
287 {
288 	int i;
289 
290 	for (i = 0; i < 20; i++) {
291 		multiorder_check(200, i);
292 		multiorder_check(0, i);
293 		multiorder_check((1UL << i) + 1, i);
294 	}
295 
296 	for (i = 0; i < 15; i++)
297 		multiorder_shrink((1UL << (i + RADIX_TREE_MAP_SHIFT)), i);
298 
299 	multiorder_insert_bug();
300 	multiorder_tag_tests();
301 	multiorder_iteration();
302 	multiorder_tagged_iteration();
303 }
304