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 const struct timestamp_expectation test_data[] = {
84	{
85		.test_case_name = LOWER_BOUND_NEG_NO_EXTRA_BITS_CASE,
86		.msb_set = true,
87		.lower_bound = true,
88		.extra_bits = 0,
89		.expected = {.tv_sec = -0x80000000LL, .tv_nsec = 0L},
90	},
91
92	{
93		.test_case_name = UPPER_BOUND_NEG_NO_EXTRA_BITS_CASE,
94		.msb_set = true,
95		.lower_bound = false,
96		.extra_bits = 0,
97		.expected = {.tv_sec = -1LL, .tv_nsec = 0L},
98	},
99
100	{
101		.test_case_name = LOWER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
102		.msb_set = false,
103		.lower_bound = true,
104		.extra_bits = 0,
105		.expected = {0LL, 0L},
106	},
107
108	{
109		.test_case_name = UPPER_BOUND_NONNEG_NO_EXTRA_BITS_CASE,
110		.msb_set = false,
111		.lower_bound = false,
112		.extra_bits = 0,
113		.expected = {.tv_sec = 0x7fffffffLL, .tv_nsec = 0L},
114	},
115
116	{
117		.test_case_name = LOWER_BOUND_NEG_LO_1_CASE,
118		.msb_set = true,
119		.lower_bound = true,
120		.extra_bits = 1,
121		.expected = {.tv_sec = 0x80000000LL, .tv_nsec = 0L},
122	},
123
124	{
125		.test_case_name = UPPER_BOUND_NEG_LO_1_CASE,
126		.msb_set = true,
127		.lower_bound = false,
128		.extra_bits = 1,
129		.expected = {.tv_sec = 0xffffffffLL, .tv_nsec = 0L},
130	},
131
132	{
133		.test_case_name = LOWER_BOUND_NONNEG_LO_1_CASE,
134		.msb_set = false,
135		.lower_bound = true,
136		.extra_bits = 1,
137		.expected = {.tv_sec = 0x100000000LL, .tv_nsec = 0L},
138	},
139
140	{
141		.test_case_name = UPPER_BOUND_NONNEG_LO_1_CASE,
142		.msb_set = false,
143		.lower_bound = false,
144		.extra_bits = 1,
145		.expected = {.tv_sec = 0x17fffffffLL, .tv_nsec = 0L},
146	},
147
148	{
149		.test_case_name = LOWER_BOUND_NEG_HI_1_CASE,
150		.msb_set = true,
151		.lower_bound = true,
152		.extra_bits =  2,
153		.expected = {.tv_sec = 0x180000000LL, .tv_nsec = 0L},
154	},
155
156	{
157		.test_case_name = UPPER_BOUND_NEG_HI_1_CASE,
158		.msb_set = true,
159		.lower_bound = false,
160		.extra_bits = 2,
161		.expected = {.tv_sec = 0x1ffffffffLL, .tv_nsec = 0L},
162	},
163
164	{
165		.test_case_name = LOWER_BOUND_NONNEG_HI_1_CASE,
166		.msb_set = false,
167		.lower_bound = true,
168		.extra_bits = 2,
169		.expected = {.tv_sec = 0x200000000LL, .tv_nsec = 0L},
170	},
171
172	{
173		.test_case_name = UPPER_BOUND_NONNEG_HI_1_CASE,
174		.msb_set = false,
175		.lower_bound = false,
176		.extra_bits = 2,
177		.expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 0L},
178	},
179
180	{
181		.test_case_name = UPPER_BOUND_NONNEG_HI_1_NS_1_CASE,
182		.msb_set = false,
183		.lower_bound = false,
184		.extra_bits = 6,
185		.expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 1L},
186	},
187
188	{
189		.test_case_name = LOWER_BOUND_NONNEG_HI_1_NS_MAX_CASE,
190		.msb_set = false,
191		.lower_bound = true,
192		.extra_bits = 0xFFFFFFFF,
193		.expected = {.tv_sec = 0x300000000LL,
194			     .tv_nsec = MAX_NANOSECONDS},
195	},
196
197	{
198		.test_case_name = LOWER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
199		.msb_set = false,
200		.lower_bound = true,
201		.extra_bits = 3,
202		.expected = {.tv_sec = 0x300000000LL, .tv_nsec = 0L},
203	},
204
205	{
206		.test_case_name = UPPER_BOUND_NONNEG_EXTRA_BITS_1_CASE,
207		.msb_set = false,
208		.lower_bound = false,
209		.extra_bits = 3,
210		.expected = {.tv_sec = 0x37fffffffLL, .tv_nsec = 0L},
211	}
212};
213
214static void timestamp_expectation_to_desc(const struct timestamp_expectation *t,
215					  char *desc)
216{
217	strscpy(desc, t->test_case_name, KUNIT_PARAM_DESC_SIZE);
218}
219
220KUNIT_ARRAY_PARAM(ext4_inode, test_data, timestamp_expectation_to_desc);
221
222static time64_t get_32bit_time(const struct timestamp_expectation * const test)
223{
224	if (test->msb_set) {
225		if (test->lower_bound)
226			return LOWER_MSB_1;
227
228		return UPPER_MSB_1;
229	}
230
231	if (test->lower_bound)
232		return LOWER_MSB_0;
233	return UPPER_MSB_0;
234}
235
236
237/*
238 *  Test data is derived from the table in the Inode Timestamps section of
239 *  Documentation/filesystems/ext4/inodes.rst.
240 */
241static void inode_test_xtimestamp_decoding(struct kunit *test)
242{
243	struct timespec64 timestamp;
244
245	struct timestamp_expectation *test_param =
246			(struct timestamp_expectation *)(test->param_value);
247
248	timestamp = ext4_decode_extra_time(
249				cpu_to_le32(get_32bit_time(test_param)),
250				cpu_to_le32(test_param->extra_bits));
251
252	KUNIT_EXPECT_EQ_MSG(test,
253			    test_param->expected.tv_sec,
254			    timestamp.tv_sec,
255			    CASE_NAME_FORMAT,
256			    test_param->test_case_name,
257			    test_param->msb_set,
258			    test_param->lower_bound,
259			    test_param->extra_bits);
260	KUNIT_EXPECT_EQ_MSG(test,
261			    test_param->expected.tv_nsec,
262			    timestamp.tv_nsec,
263			    CASE_NAME_FORMAT,
264			    test_param->test_case_name,
265			    test_param->msb_set,
266			    test_param->lower_bound,
267			    test_param->extra_bits);
268}
269
270static struct kunit_case ext4_inode_test_cases[] = {
271	KUNIT_CASE_PARAM(inode_test_xtimestamp_decoding, ext4_inode_gen_params),
272	{}
273};
274
275static struct kunit_suite ext4_inode_test_suite = {
276	.name = "ext4_inode_test",
277	.test_cases = ext4_inode_test_cases,
278};
279
280kunit_test_suites(&ext4_inode_test_suite);
281
282MODULE_LICENSE("GPL v2");
283