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 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");