xref: /linux/fs/ext4/inode-test.c (revision 26bff9eb49201aeb4e1b32d698c191831a39f5d4)
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 
75 struct 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 
83 static 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  */
102 static 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 
262 static struct kunit_case ext4_inode_test_cases[] = {
263 	KUNIT_CASE(inode_test_xtimestamp_decoding),
264 	{}
265 };
266 
267 static struct kunit_suite ext4_inode_test_suite = {
268 	.name = "ext4_inode_test",
269 	.test_cases = ext4_inode_test_cases,
270 };
271 
272 kunit_test_suites(&ext4_inode_test_suite);
273 
274 MODULE_LICENSE("GPL v2");
275