xref: /kernel/linux/linux-5.10/fs/ext4/inode-test.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * KUnit test of ext4 inode that verify the seconds part of [a/c/m]
4 * timestamps in ext4 inode structs are decoded correctly.
5 */
6
7#include <kunit/test.h>
8#include <linux/kernel.h>
9#include <linux/time64.h>
10
11#include "ext4.h"
12
13/*
14 * For constructing the nonnegative timestamp lower bound value.
15 * binary: 00000000 00000000 00000000 00000000
16 */
17#define LOWER_MSB_0 0L
18/*
19 * For constructing the nonnegative timestamp upper bound value.
20 * binary: 01111111 11111111 11111111 11111111
21 *
22 */
23#define UPPER_MSB_0 0x7fffffffL
24/*
25 * For constructing the negative timestamp lower bound value.
26 * binary: 10000000 00000000 00000000 00000000
27 */
28#define LOWER_MSB_1 (-(UPPER_MSB_0) - 1L)  /* avoid overflow */
29/*
30 * For constructing the negative timestamp upper bound value.
31 * binary: 11111111 11111111 11111111 11111111
32 */
33#define UPPER_MSB_1 (-1L)
34/*
35 * Upper bound for nanoseconds value supported by the encoding.
36 * binary: 00111111 11111111 11111111 11111111
37 */
38#define MAX_NANOSECONDS ((1L << 30) - 1)
39
40#define CASE_NAME_FORMAT "%s: msb:%x lower_bound:%x extra_bits: %x"
41
42#define LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE\
43	"1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits"
44#define UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE\
45	"1969-12-31 Upper bound of 32bit < 0 timestamp, no extra bits"
46#define LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\
47	"1970-01-01 Lower bound of 32bit >=0 timestamp, no extra bits"
48#define UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE\
49	"2038-01-19 Upper bound of 32bit >=0 timestamp, no extra bits"
50#define LOWER_BOUND_NEG_LO_1_CASE\
51	"2038-01-19 Lower bound of 32bit <0 timestamp, lo extra sec bit on"
52#define UPPER_BOUND_NEG_LO_1_CASE\
53	"2106-02-07 Upper bound of 32bit <0 timestamp, lo extra sec bit on"
54#define LOWER_BOUND_NONNEG_LO_1_CASE\
55	"2106-02-07 Lower bound of 32bit >=0 timestamp, lo extra sec bit on"
56#define UPPER_BOUND_NONNEG_LO_1_CASE\
57	"2174-02-25 Upper bound of 32bit >=0 timestamp, lo extra sec bit on"
58#define LOWER_BOUND_NEG_HI_1_CASE\
59	"2174-02-25 Lower bound of 32bit <0 timestamp, hi extra sec bit on"
60#define UPPER_BOUND_NEG_HI_1_CASE\
61	"2242-03-16 Upper bound of 32bit <0 timestamp, hi extra sec bit on"
62#define LOWER_BOUND_NONNEG_HI_1_CASE\
63	"2242-03-16 Lower bound of 32bit >=0 timestamp, hi extra sec bit on"
64#define UPPER_BOUND_NONNEG_HI_1_CASE\
65	"2310-04-04 Upper bound of 32bit >=0 timestamp, hi extra sec bit on"
66#define UPPER_BOUND_NONNEG_HI_1_NS_1_CASE\
67	"2310-04-04 Upper bound of 32bit>=0 timestamp, hi extra sec bit 1. 1 ns"
68#define LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE\
69	"2378-04-22 Lower bound of 32bit>= timestamp. Extra sec bits 1. Max ns"
70#define LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE\
71	"2378-04-22 Lower bound of 32bit >=0 timestamp. All extra sec bits on"
72#define UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE\
73	"2446-05-10 Upper bound of 32bit >=0 timestamp. All extra sec bits on"
74
75struct timestamp_expectation {
76	const char *test_case_name;
77	struct timespec64 expected;
78	u32 extra_bits;
79	bool msb_set;
80	bool lower_bound;
81};
82
83static time64_t get_32bit_time(const struct timestamp_expectation * const test)
84{
85	if (test->msb_set) {
86		if (test->lower_bound)
87			return LOWER_MSB_1;
88
89		return UPPER_MSB_1;
90	}
91
92	if (test->lower_bound)
93		return LOWER_MSB_0;
94	return UPPER_MSB_0;
95}
96
97
98/*
99 *  Test data is derived from the table in the Inode Timestamps section of
100 *  Documentation/filesystems/ext4/inodes.rst.
101 */
102static void inode_test_xtimestamp_decoding(struct kunit *test)
103{
104	const struct timestamp_expectation test_data[] = {
105		{
106			.test_case_name = LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE,
107			.msb_set = true,
108			.lower_bound = true,
109			.extra_bits = 0,
110			.expected = {.tv_sec = -0x80000000LL, .tv_nsec = 0L},
111		},
112
113		{
114			.test_case_name = UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE,
115			.msb_set = true,
116			.lower_bound = false,
117			.extra_bits = 0,
118			.expected = {.tv_sec = -1LL, .tv_nsec = 0L},
119		},
120
121		{
122			.test_case_name = LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
123			.msb_set = false,
124			.lower_bound = true,
125			.extra_bits = 0,
126			.expected = {0LL, 0L},
127		},
128
129		{
130			.test_case_name = UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
131			.msb_set = false,
132			.lower_bound = false,
133			.extra_bits = 0,
134			.expected = {.tv_sec = 0x7fffffffLL, .tv_nsec = 0L},
135		},
136
137		{
138			.test_case_name = LOWER_BOUND_NEG_LO_1_CASE,
139			.msb_set = true,
140			.lower_bound = true,
141			.extra_bits = 1,
142			.expected = {.tv_sec = 0x80000000LL, .tv_nsec = 0L},
143		},
144
145		{
146			.test_case_name = UPPER_BOUND_NEG_LO_1_CASE,
147			.msb_set = true,
148			.lower_bound = false,
149			.extra_bits = 1,
150			.expected = {.tv_sec = 0xffffffffLL, .tv_nsec = 0L},
151		},
152
153		{
154			.test_case_name = LOWER_BOUND_NONNEG_LO_1_CASE,
155			.msb_set = false,
156			.lower_bound = true,
157			.extra_bits = 1,
158			.expected = {.tv_sec = 0x100000000LL, .tv_nsec = 0L},
159		},
160
161		{
162			.test_case_name = UPPER_BOUND_NONNEG_LO_1_CASE,
163			.msb_set = false,
164			.lower_bound = false,
165			.extra_bits = 1,
166			.expected = {.tv_sec = 0x17fffffffLL, .tv_nsec = 0L},
167		},
168
169		{
170			.test_case_name = LOWER_BOUND_NEG_HI_1_CASE,
171			.msb_set = true,
172			.lower_bound = true,
173			.extra_bits =  2,
174			.expected = {.tv_sec = 0x180000000LL, .tv_nsec = 0L},
175		},
176
177		{
178			.test_case_name = UPPER_BOUND_NEG_HI_1_CASE,
179			.msb_set = true,
180			.lower_bound = false,
181			.extra_bits = 2,
182			.expected = {.tv_sec = 0x1ffffffffLL, .tv_nsec = 0L},
183		},
184
185		{
186			.test_case_name = LOWER_BOUND_NONNEG_HI_1_CASE,
187			.msb_set = false,
188			.lower_bound = true,
189			.extra_bits = 2,
190			.expected = {.tv_sec = 0x200000000LL, .tv_nsec = 0L},
191		},
192
193		{
194			.test_case_name = UPPER_BOUND_NONNEG_HI_1_CASE,
195			.msb_set = false,
196			.lower_bound = false,
197			.extra_bits = 2,
198			.expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 0L},
199		},
200
201		{
202			.test_case_name = UPPER_BOUND_NONNEG_HI_1_NS_1_CASE,
203			.msb_set = false,
204			.lower_bound = false,
205			.extra_bits = 6,
206			.expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 1L},
207		},
208
209		{
210			.test_case_name = LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE,
211			.msb_set = false,
212			.lower_bound = true,
213			.extra_bits = 0xFFFFFFFF,
214			.expected = {.tv_sec = 0x300000000LL,
215				     .tv_nsec = MAX_NANOSECONDS},
216		},
217
218		{
219			.test_case_name = LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
220			.msb_set = false,
221			.lower_bound = true,
222			.extra_bits = 3,
223			.expected = {.tv_sec = 0x300000000LL, .tv_nsec = 0L},
224		},
225
226		{
227			.test_case_name = UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
228			.msb_set = false,
229			.lower_bound = false,
230			.extra_bits = 3,
231			.expected = {.tv_sec = 0x37fffffffLL, .tv_nsec = 0L},
232		}
233	};
234
235	struct timespec64 timestamp;
236	int i;
237
238	for (i = 0; i < ARRAY_SIZE(test_data); ++i) {
239		timestamp.tv_sec = get_32bit_time(&test_data[i]);
240		ext4_decode_extra_time(&timestamp,
241				       cpu_to_le32(test_data[i].extra_bits));
242
243		KUNIT_EXPECT_EQ_MSG(test,
244				    test_data[i].expected.tv_sec,
245				    timestamp.tv_sec,
246				    CASE_NAME_FORMAT,
247				    test_data[i].test_case_name,
248				    test_data[i].msb_set,
249				    test_data[i].lower_bound,
250				    test_data[i].extra_bits);
251		KUNIT_EXPECT_EQ_MSG(test,
252				    test_data[i].expected.tv_nsec,
253				    timestamp.tv_nsec,
254				    CASE_NAME_FORMAT,
255				    test_data[i].test_case_name,
256				    test_data[i].msb_set,
257				    test_data[i].lower_bound,
258				    test_data[i].extra_bits);
259	}
260}
261
262static struct kunit_case ext4_inode_test_cases[] = {
263	KUNIT_CASE(inode_test_xtimestamp_decoding),
264	{}
265};
266
267static struct kunit_suite ext4_inode_test_suite = {
268	.name = "ext4_inode_test",
269	.test_cases = ext4_inode_test_cases,
270};
271
272kunit_test_suites(&ext4_inode_test_suite);
273
274MODULE_LICENSE("GPL v2");
275