2019-10-10 23:51:29

by Iurii Zaikin

[permalink] [raw]
Subject: [PATCH linux-kselftest/test v3] ext4: add kunit test for decoding extended timestamps

KUnit tests for decoding extended 64 bit timestamps
that verify the seconds part of [a/c/m]
timestamps in ext4 inode structs are decoded correctly.
KUnit tests, which run on boot and output
the results to the debug log in TAP format (http://testanything.org/).
are only useful for kernel devs running KUnit test harness. Not for
inclusion into a production build.
Test data is derive from the table under
Documentation/filesystems/ext4/inodes.rst Inode Timestamps.

Signed-off-by: Iurii Zaikin <[email protected]>
---
fs/ext4/Kconfig | 14 +++
fs/ext4/Makefile | 1 +
fs/ext4/inode-test.c | 239 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 254 insertions(+)
create mode 100644 fs/ext4/inode-test.c

diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index cbb5ca830e57..605c3d506934 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -106,3 +106,17 @@ config EXT4_DEBUG
If you select Y here, then you will be able to turn on debugging
with a command such as:
echo 1 > /sys/module/ext4/parameters/mballoc_debug
+
+config EXT4_KUNIT_TESTS
+ bool "KUnit test for ext4 inode"
+ depends on EXT4_FS
+ depends on KUNIT
+ help
+ This builds the ext4 KUnit tests, which run on boot and output
+ the results to the debug log in TAP format (http://testanything.org/).
+ Only useful for kernel devs running KUnit test harness. Not for
+ inclusion into a production build.
+ For more information on KUnit and unit tests in general please refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+ If unsure, say N.
diff --git a/fs/ext4/Makefile b/fs/ext4/Makefile
index b17ddc229ac5..a0588fd2eea6 100644
--- a/fs/ext4/Makefile
+++ b/fs/ext4/Makefile
@@ -13,4 +13,5 @@ ext4-y := balloc.o bitmap.o block_validity.o dir.o ext4_jbd2.o extents.o \

ext4-$(CONFIG_EXT4_FS_POSIX_ACL) += acl.o
ext4-$(CONFIG_EXT4_FS_SECURITY) += xattr_security.o
+ext4-$(CONFIG_EXT4_KUNIT_TESTS) += inode-test.o
ext4-$(CONFIG_FS_VERITY) += verity.o
diff --git a/fs/ext4/inode-test.c b/fs/ext4/inode-test.c
new file mode 100644
index 000000000000..3b3a453ff382
--- /dev/null
+++ b/fs/ext4/inode-test.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test of ext4 inode that verify the seconds part of [a/c/m]
+ * timestamps in ext4 inode structs are decoded correctly.
+ */
+
+#include <kunit/test.h>
+#include <linux/kernel.h>
+#include <linux/time64.h>
+
+#include "ext4.h"
+
+/* binary: 00000000 00000000 00000000 00000000 */
+#define LOWER_MSB_0 0L
+/* binary: 01111111 11111111 11111111 11111111 */
+#define UPPER_MSB_0 0x7fffffffL
+/* binary: 10000000 00000000 00000000 00000000 */
+#define LOWER_MSB_1 (-0x80000000L)
+/* binary: 11111111 11111111 11111111 11111111 */
+#define UPPER_MSB_1 (-1L)
+/* binary: 00111111 11111111 11111111 11111111 */
+#define MAX_NANOSECONDS ((1L << 30) - 1)
+
+#define CASE_NAME_FORMAT "%s: msb:%x lower_bound:%x extra_bits: %x"
+
+struct timestamp_expectation {
+ const char *test_case_name;
+ struct timespec64 expected;
+ u32 extra_bits;
+ bool msb_set;
+ bool lower_bound;
+};
+
+static time64_t get_32bit_time(const struct timestamp_expectation * const test)
+{
+ if (test->msb_set) {
+ if (test->lower_bound)
+ return LOWER_MSB_1;
+
+ return UPPER_MSB_1;
+ }
+
+ if (test->lower_bound)
+ return LOWER_MSB_0;
+ return UPPER_MSB_0;
+}
+
+
+/*
+ * These tests are derived from the table under
+ * Documentation/filesystems/ext4/inodes.rst Inode Timestamps
+ */
+static void inode_test_xtimestamp_decoding(struct kunit *test)
+{
+ const struct timestamp_expectation test_data[] = {
+ {
+ .test_case_name =
+ "1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits.",
+ .msb_set = true,
+ .lower_bound = true,
+ .extra_bits = 0,
+ .expected = {.tv_sec = -0x80000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "1969-12-31 Upper bound of 32bit < 0 timestamp, no extra bits.",
+ .msb_set = true,
+ .lower_bound = false,
+ .extra_bits = 0,
+ .expected = {.tv_sec = -1LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "1970-01-01 Lower bound of 32bit >=0 timestamp, no extra bits.",
+ .msb_set = false,
+ .lower_bound = true,
+ .extra_bits = 0,
+ .expected = {0LL, 0L},
+ },
+
+ {
+ .test_case_name =
+ "2038-01-19 Upper bound of 32bit >=0 timestamp, no extra bits.",
+ .msb_set = false,
+ .lower_bound = false,
+ .extra_bits = 0,
+ .expected = {.tv_sec = 0x7fffffffLL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2038-01-19 Lower bound of 32bit <0 timestamp, lo extra sec bit on.",
+ .msb_set = true,
+ .lower_bound = true,
+ .extra_bits = 1,
+ .expected = {.tv_sec = 0x80000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2106-02-07 Upper bound of 32bit <0 timestamp, lo extra sec bit on.",
+ .msb_set = true,
+ .lower_bound = false,
+ .extra_bits = 1,
+ .expected = {.tv_sec = 0xffffffffLL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2106-02-07 Lower bound of 32bit >=0 timestamp, lo extra sec bit on.",
+ .msb_set = false,
+ .lower_bound = true,
+ .extra_bits = 1,
+ .expected = {.tv_sec = 0x100000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2174-02-25 Upper bound of 32bit >=0 timestamp, lo extra sec bit on.",
+ .msb_set = false,
+ .lower_bound = false,
+ .extra_bits = 1,
+ .expected = {.tv_sec = 0x17fffffffLL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2174-02-25 Lower bound of 32bit <0 timestamp, hi extra sec bit on.",
+ .msb_set = true,
+ .lower_bound = true,
+ .extra_bits = 2,
+ .expected = {.tv_sec = 0x180000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2242-03-16 Upper bound of 32bit <0 timestamp, hi extra sec bit on.",
+ .msb_set = true,
+ .lower_bound = false,
+ .extra_bits = 2,
+ .expected = {.tv_sec = 0x1ffffffffLL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2242-03-16 Lower bound of 32bit >=0 timestamp, hi extra sec bit on.",
+ .msb_set = false,
+ .lower_bound = true,
+ .extra_bits = 2,
+ .expected = {.tv_sec = 0x200000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2310-04-04 Upper bound of 32bit >=0 timestamp, hi extra sec bit on.",
+ .msb_set = false,
+ .lower_bound = false,
+ .extra_bits = 2,
+ .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+"2310-04-04 Upper bound of 32bit>=0 timestamp, hi extra sec bit 1. 1 ns bit 1.",
+ .msb_set = false,
+ .lower_bound = false,
+ .extra_bits = 6,
+ .expected = {.tv_sec = 0x27fffffffLL, .tv_nsec = 1L},
+ },
+
+ {
+ .test_case_name =
+"2378-04-22 Lower bound of 32bit>= timestamp. Extra sec bits 1. ns bits 1.",
+ .msb_set = false,
+ .lower_bound = true,
+ .extra_bits = 0xFFFFFFFF,
+ .expected = {.tv_sec = 0x300000000LL,
+ .tv_nsec = MAX_NANOSECONDS},
+ },
+
+ {
+ .test_case_name =
+ "2378-04-22 Lower bound of 32bit >= timestamp. All extra sec bits on.",
+ .msb_set = false,
+ .lower_bound = true,
+ .extra_bits = 3,
+ .expected = {.tv_sec = 0x300000000LL, .tv_nsec = 0L},
+ },
+
+ {
+ .test_case_name =
+ "2446-05-10 Upper bound of 32bit >= timestamp. All extra sec bits on.",
+ .msb_set = false,
+ .lower_bound = false,
+ .extra_bits = 3,
+ .expected = {.tv_sec = 0x37fffffffLL, .tv_nsec = 0L},
+ }
+ };
+
+ struct timespec64 timestamp;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(test_data); ++i) {
+ timestamp.tv_sec = get_32bit_time(&test_data[i]);
+ ext4_decode_extra_time(&timestamp,
+ cpu_to_le32(test_data[i].extra_bits));
+
+ KUNIT_EXPECT_EQ_MSG(test,
+ test_data[i].expected.tv_sec,
+ timestamp.tv_sec,
+ CASE_NAME_FORMAT,
+ test_data[i].test_case_name,
+ test_data[i].msb_set,
+ test_data[i].lower_bound,
+ test_data[i].extra_bits);
+ KUNIT_EXPECT_EQ_MSG(test,
+ test_data[i].expected.tv_nsec,
+ timestamp.tv_nsec,
+ CASE_NAME_FORMAT,
+ test_data[i].test_case_name,
+ test_data[i].msb_set,
+ test_data[i].lower_bound,
+ test_data[i].extra_bits);
+ }
+}
+
+static struct kunit_case ext4_inode_test_cases[] = {
+ KUNIT_CASE(inode_test_xtimestamp_decoding),
+ {}
+};
+
+static struct kunit_suite ext4_inode_test_suite = {
+ .name = "ext4_inode_test",
+ .test_cases = ext4_inode_test_cases,
+};
+
+kunit_test_suite(ext4_inode_test_suite);
--
2.23.0.700.g56cf767bdb-goog


2019-10-16 16:34:37

by Theodore Ts'o

[permalink] [raw]
Subject: Re: [PATCH linux-kselftest/test v3] ext4: add kunit test for decoding extended timestamps

On Thu, Oct 10, 2019 at 04:50:30PM -0700, Iurii Zaikin wrote:
> KUnit tests for decoding extended 64 bit timestamps
> that verify the seconds part of [a/c/m]
> timestamps in ext4 inode structs are decoded correctly.
> KUnit tests, which run on boot and output
> the results to the debug log in TAP format (http://testanything.org/).
> are only useful for kernel devs running KUnit test harness. Not for
> inclusion into a production build.
> Test data is derive from the table under
> Documentation/filesystems/ext4/inodes.rst Inode Timestamps.
>
> Signed-off-by: Iurii Zaikin <[email protected]>

This looks good. Thanks, Iurii!

Reviewed-by: Theodore Ts'o <[email protected]>

- Ted