fs/ext4/inode-test.c

   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 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
 214 static 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
 220 KUNIT_ARRAY_PARAM(ext4_inode, test_data, timestamp_expectation_to_desc);
 221
 222 static 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  */
 241 static 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
 270 static struct kunit_case ext4_inode_test_cases[] = {
 271         KUNIT_CASE_PARAM(inode_test_xtimestamp_decoding, ext4_inode_gen_params),
 272         {}
 273 };
 274
 275 static struct kunit_suite ext4_inode_test_suite = {
 276         .name = "ext4_inode_test",
 277         .test_cases = ext4_inode_test_cases,
 278 };
 279
 280 kunit_test_suites(&ext4_inode_test_suite);
 281
 282 MODULE_DESCRIPTION("KUnit test of ext4 inode timestamp decoding");
 283 MODULE_LICENSE("GPL v2");