ext4: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-40-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: ext4: Modify inode-test.c to use KUnit parameterized testing feature

Modify fs/ext4/inode-test.c to use the parameterized testing
feature of KUnit.

Signed-off-by: Arpitha Raghunandan <98.arpi@gmail.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: David Gow <davidgow@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Reviewed-by: Iurii Zaikin <yzaikin@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kunit: allow kunit tests to be loaded as a module

As tests are added to kunit, it will become less feasible to execute
all built tests together. By supporting modular tests we provide
a simple way to do selective execution on a running system; specifying

CONFIG_KUNIT=y
CONFIG_KUNIT_EXAMPLE_TEST=m

...means we can simply "insmod example-test.ko" to run the tests.

To achieve this we need to do the following:

o export the required symbols in kunit
o string-stream tests utilize non-exported symbols so for now we skip
building them when CONFIG_KUNIT_TEST=m.
o drivers/base/power/qos-test.c contains a few unexported interface
references, namely freq_qos_read_value() and freq_constraints_init().
Both of these could be potentially defined as static inline functions
in include/linux/pm_qos.h, but for now we simply avoid supporting
module build for that test suite.
o support a new way of declaring test suites. Because a module cannot
do multiple late_initcall()s, we provide a kunit_test_suites() macro
to declare multiple suites within the same module at once.
o some test module names would have been too general ("test-test"
and "example-test" for kunit tests, "inode-test" for ext4 tests);
rename these as appropriate ("kunit-test", "kunit-example-test"
and "ext4-inode-test" respectively).

Also define kunit_test_suite() via kunit_test_suites()
as callers in other trees may need the old definition.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits
Acked-by: David Gow <davidgow@google.com> # For list-test
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

fs/ext4/inode-test: Fix inode test on 32 bit platforms.

Fixes the issue caused by the fact that in C in the expression
of the form -1234L only 1234L is the actual literal, the unary
minus is an operation applied to the literal. Which means that
to express the lower bound for the type one has to negate the
upper bound and subtract 1.

Original error:
Expected test_data[i].expected.tv_sec == timestamp.tv_sec, but
test_data[i].expected.tv_sec == -2147483648
timestamp.tv_sec == 2147483648
1901-12-13 Lower bound of 32bit < 0 timestamp, no extra bits: msb:1
lower_bound:1 extra_bits: 0
Expected test_data[i].expected.tv_sec == timestamp.tv_sec, but
test_data[i].expected.tv_sec == 2147483648
timestamp.tv_sec == 6442450944
2038-01-19 Lower bound of 32bit <0 timestamp, lo extra sec bit on:
msb:1 lower_bound:1 extra_bits: 1
Expected test_data[i].expected.tv_sec == timestamp.tv_sec, but
test_data[i].expected.tv_sec == 6442450944
timestamp.tv_sec == 10737418240
2174-02-25 Lower bound of 32bit <0 timestamp, hi extra sec bit on:
msb:1 lower_bound:1 extra_bits: 2
not ok 1 - inode_test_xtimestamp_decoding
not ok 1 - ext4_inode_test

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Iurii Zaikin <yzaikin@google.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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.

Test data is derived from the table in the Inode Timestamps section of
Documentation/filesystems/ext4/inodes.rst.

KUnit tests run during boot and output the results to the debug log
in TAP format (http://testanything.org/). Only useful for kernel devs
running KUnit test harness and are not for inclusion into a production
build.

Signed-off-by: Iurii Zaikin <yzaikin@google.com>
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>