summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/vm/madv_populate.c
blob: 715a42e8e2cdb601bbc97d2c0cd05e8a7177e591 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
// SPDX-License-Identifier: GPL-2.0-only
/*
 * MADV_POPULATE_READ and MADV_POPULATE_WRITE tests
 *
 * Copyright 2021, Red Hat, Inc.
 *
 * Author(s): David Hildenbrand <david@redhat.com>
 */
#define _GNU_SOURCE
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/mman.h>
#include <sys/mman.h>

#include "../kselftest.h"
#include "vm_util.h"

/*
 * For now, we're using 2 MiB of private anonymous memory for all tests.
 */
#define SIZE (2 * 1024 * 1024)

static size_t pagesize;

static bool pagemap_is_populated(int fd, char *start)
{
	uint64_t entry = pagemap_get_entry(fd, start);

	/* Present or swapped. */
	return entry & 0xc000000000000000ull;
}

static void sense_support(void)
{
	char *addr;
	int ret;

	addr = mmap(0, pagesize, PROT_READ | PROT_WRITE,
		    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (!addr)
		ksft_exit_fail_msg("mmap failed\n");

	ret = madvise(addr, pagesize, MADV_POPULATE_READ);
	if (ret)
		ksft_exit_skip("MADV_POPULATE_READ is not available\n");

	ret = madvise(addr, pagesize, MADV_POPULATE_WRITE);
	if (ret)
		ksft_exit_skip("MADV_POPULATE_WRITE is not available\n");

	munmap(addr, pagesize);
}

static void test_prot_read(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_READ);
	ksft_test_result(!ret, "MADV_POPULATE_READ with PROT_READ\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
	ksft_test_result(ret == -1 && errno == EINVAL,
			 "MADV_POPULATE_WRITE with PROT_READ\n");

	munmap(addr, SIZE);
}

static void test_prot_write(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_READ);
	ksft_test_result(ret == -1 && errno == EINVAL,
			 "MADV_POPULATE_READ with PROT_WRITE\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
	ksft_test_result(!ret, "MADV_POPULATE_WRITE with PROT_WRITE\n");

	munmap(addr, SIZE);
}

static void test_holes(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
		    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");
	ret = munmap(addr + pagesize, pagesize);
	if (ret)
		ksft_exit_fail_msg("munmap failed\n");

	/* Hole in the middle */
	ret = madvise(addr, SIZE, MADV_POPULATE_READ);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_READ with holes in the middle\n");
	ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_WRITE with holes in the middle\n");

	/* Hole at end */
	ret = madvise(addr, 2 * pagesize, MADV_POPULATE_READ);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_READ with holes at the end\n");
	ret = madvise(addr, 2 * pagesize, MADV_POPULATE_WRITE);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_WRITE with holes at the end\n");

	/* Hole at beginning */
	ret = madvise(addr + pagesize, pagesize, MADV_POPULATE_READ);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_READ with holes at the beginning\n");
	ret = madvise(addr + pagesize, pagesize, MADV_POPULATE_WRITE);
	ksft_test_result(ret == -1 && errno == ENOMEM,
			 "MADV_POPULATE_WRITE with holes at the beginning\n");

	munmap(addr, SIZE);
}

static bool range_is_populated(char *start, ssize_t size)
{
	int fd = open("/proc/self/pagemap", O_RDONLY);
	bool ret = true;

	if (fd < 0)
		ksft_exit_fail_msg("opening pagemap failed\n");
	for (; size > 0 && ret; size -= pagesize, start += pagesize)
		if (!pagemap_is_populated(fd, start))
			ret = false;
	close(fd);
	return ret;
}

static bool range_is_not_populated(char *start, ssize_t size)
{
	int fd = open("/proc/self/pagemap", O_RDONLY);
	bool ret = true;

	if (fd < 0)
		ksft_exit_fail_msg("opening pagemap failed\n");
	for (; size > 0 && ret; size -= pagesize, start += pagesize)
		if (pagemap_is_populated(fd, start))
			ret = false;
	close(fd);
	return ret;
}

static void test_populate_read(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
		    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");
	ksft_test_result(range_is_not_populated(addr, SIZE),
			 "range initially not populated\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_READ);
	ksft_test_result(!ret, "MADV_POPULATE_READ\n");
	ksft_test_result(range_is_populated(addr, SIZE),
			 "range is populated\n");

	munmap(addr, SIZE);
}

static void test_populate_write(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
		    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");
	ksft_test_result(range_is_not_populated(addr, SIZE),
			 "range initially not populated\n");

	ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
	ksft_test_result(!ret, "MADV_POPULATE_WRITE\n");
	ksft_test_result(range_is_populated(addr, SIZE),
			 "range is populated\n");

	munmap(addr, SIZE);
}

static bool range_is_softdirty(char *start, ssize_t size)
{
	int fd = open("/proc/self/pagemap", O_RDONLY);
	bool ret = true;

	if (fd < 0)
		ksft_exit_fail_msg("opening pagemap failed\n");
	for (; size > 0 && ret; size -= pagesize, start += pagesize)
		if (!pagemap_is_softdirty(fd, start))
			ret = false;
	close(fd);
	return ret;
}

static bool range_is_not_softdirty(char *start, ssize_t size)
{
	int fd = open("/proc/self/pagemap", O_RDONLY);
	bool ret = true;

	if (fd < 0)
		ksft_exit_fail_msg("opening pagemap failed\n");
	for (; size > 0 && ret; size -= pagesize, start += pagesize)
		if (pagemap_is_softdirty(fd, start))
			ret = false;
	close(fd);
	return ret;
}

static void test_softdirty(void)
{
	char *addr;
	int ret;

	ksft_print_msg("[RUN] %s\n", __func__);

	addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
		    MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
	if (addr == MAP_FAILED)
		ksft_exit_fail_msg("mmap failed\n");

	/* Clear any softdirty bits. */
	clear_softdirty();
	ksft_test_result(range_is_not_softdirty(addr, SIZE),
			 "range is not softdirty\n");

	/* Populating READ should set softdirty. */
	ret = madvise(addr, SIZE, MADV_POPULATE_READ);
	ksft_test_result(!ret, "MADV_POPULATE_READ\n");
	ksft_test_result(range_is_not_softdirty(addr, SIZE),
			 "range is not softdirty\n");

	/* Populating WRITE should set softdirty. */
	ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
	ksft_test_result(!ret, "MADV_POPULATE_WRITE\n");
	ksft_test_result(range_is_softdirty(addr, SIZE),
			 "range is softdirty\n");

	munmap(addr, SIZE);
}

int main(int argc, char **argv)
{
	int err;

	pagesize = getpagesize();

	ksft_print_header();
	ksft_set_plan(21);

	sense_support();
	test_prot_read();
	test_prot_write();
	test_holes();
	test_populate_read();
	test_populate_write();
	test_softdirty();

	err = ksft_get_fail_cnt();
	if (err)
		ksft_exit_fail_msg("%d out of %d tests failed\n",
				   err, ksft_test_num());
	return ksft_exit_pass();
}