selftests: gpio: Fix incorrect kernel headers search path

Use $(KHDR_INCLUDES) as lookup path for kernel headers. This prevents
building against kernel headers from the build environment in scenarios
where kernel headers are installed into a specific output directory
(O=...).

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org> # 5.18+
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: gpio: fix include path to kernel headers for out of tree builds

When building selftests out of the kernel tree the gpio.h the include
path is incorrect and the build falls back to the system includes
which may be outdated.

Add the KHDR_INCLUDES to the CFLAGS to include the gpio.h from the
build tree.

Fixes: 4f4d0af7b2d9 ("selftests: gpio: restore CFLAGS options")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: add test cases for gpio-sim

Add a set of tests for the new gpio-sim module. This is a pure shell
test-suite and uses the helper programs available in the gpio selftests
directory. These test-cases only test the functionalities exposed by the
gpio-sim driver, not those handled by core gpiolib code.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: add a helper for reading GPIO line names

Add a simple program that allows to read GPIO line names from the
character device. This will be used in gpio-sim selftests.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: provide a helper for reading chip info

Add a simple program that allows to retrieve chip properties from the
GPIO character device. This will be used in gpio-sim selftests.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: restore CFLAGS options

All the CFLAGS options were incorrectly removed in the recent rework
of the GPIO selftests. While some of the flags were specific to the old
implementation the remainder are still relevant. Restore those options.

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: fix gpio compiling error

The gpio selftests build against the system includes rather than the
headers from the linux tree. This results in the compile failing if
the system includes are outdated.

Prefer the headers from the linux tree, as per other selftests.

Fixes: 8bc395a6a2e2 ("selftests: gpio: rework and simplify test implementation")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
[Kent: reworded commit comment and added Fixes:]
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

selftests: gpio: rework and simplify test implementation

The GPIO mockup selftests are overly complicated with separate
implementations of the tests for sysfs and cdev uAPI, and with the cdev
implementation being dependent on tools/gpio and libmount.

Rework the test implementation to provide a common test suite with a
simplified pluggable uAPI interface. The cdev implementation utilises
the GPIO uAPI directly to remove the dependence on tools/gpio.
The simplified uAPI interface removes the need for any file system mount
checks in C, and so removes the dependence on libmount.

The rework also fixes the sysfs test implementation which has been broken
since the device created in the multiple gpiochip case was split into
separate devices.

Fixes: 8a39f597bcfd ("gpio: mockup: rework device probing")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

selftests/gpio: Add to CLEAN rule rather than overriding

Rather than overriding the CLEAN rule we can just append to it.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/gpio: Fix build when source tree is read only

Currently the gpio selftests fail to build if the source tree is read
only:

make -j 160 -C tools/testing/selftests TARGETS=gpio
make[1]: Entering directory '/linux/tools/testing/selftests/gpio'
make OUTPUT=/linux/tools/gpio/ -C /linux/tools/gpio
make[2]: Entering directory '/linux/tools/gpio'
mkdir -p /linux/tools/gpio/include/linux 2>&1 || true
ln -sf /linux/tools/gpio/../../include/uapi/linux/gpio.h /linux/tools/gpio/include/linux/gpio.h
ln: failed to create symbolic link '/linux/tools/gpio/include/linux/gpio.h': Read-only file system

This happens because we ask make to build ../../../gpio (tools/gpio)
without pointing OUTPUT away from the source directory.

To fix it we create a subdirectory of the existing OUTPUT directory,
called tools-gpio, and tell tools/gpio to build in there.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/gpio: Move include of lib.mk up

Move the include of lib.mk up so that in a subsequent patch we can use
OUTPUT, which is initialised by lib.mk, in the definition of the GPIO
variables.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/gpio: Use TEST_GEN_PROGS_EXTENDED

Use TEST_GEN_PROGS_EXTENDED rather than TEST_PROGS_EXTENDED.

That tells the lib.mk logic that the files it references are to be
generated by the Makefile.

Having done that we don't need to override the all rule.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: add build/cross-build dependency check script

Add build/cross-build dependency check script kselftest_deps.sh
This script does the following:

Usage: ./kselftest_deps.sh -[p] <compiler> [test_name]

kselftest_deps.sh [-p] gcc
kselftest_deps.sh [-p] gcc vm
kselftest_deps.sh [-p] aarch64-linux-gnu-gcc
kselftest_deps.sh [-p] aarch64-linux-gnu-gcc vm

- Should be run in selftests directory in the kernel repo.
- Checks if Kselftests can be built/cross-built on a system.
- Parses all test/sub-test Makefile to find library dependencies.
- Runs compile test on a trivial C file with LDLIBS specified
in the test Makefiles to identify missing library dependencies.
- Prints suggested target list for a system filtering out tests
failed the build dependency check from the TARGETS in Selftests
the main Makefile when optional -p is specified.
- Prints pass/fail dependency check for each tests/sub-test.
- Prints pass/fail targets and libraries.
- Default: runs dependency checks on all tests.
- Optional test name can be specified to check dependencies for it.

To make LDLIBS parsing easier
- change gpio and memfd Makefiles to use the same temporary variable used
to find and add libraries to LDLIBS.
- simlify LDLIBS append logic in intel_pstate/Makefile.

Results from run on x86_64 system (trimmed detailed pass/fail list):
========================================================
Kselftest Dependency Check for [./kselftest_deps.sh gcc ] results...
========================================================
Checked tests defining LDLIBS dependencies
--------------------------------------------------------
Total tests with Dependencies:
55 Pass: 53 Fail: 2
--------------------------------------------------------
Targets passed build dependency check on system:
bpf capabilities filesystems futex gpio intel_pstate membarrier memfd
mqueue net powerpc ptp rseq rtc safesetid timens timers vDSO vm
--------------------------------------------------------
FAIL: netfilter/Makefile dependency check: -lmnl
FAIL: gpio/Makefile dependency check: -lmount
--------------------------------------------------------
Targets failed build dependency check on system:
gpio netfilter
--------------------------------------------------------
Missing libraries system
-lmnl -lmount
--------------------------------------------------------
========================================================

Results from run on x86_64 system with aarch64-linux-gnu-gcc:
(trimmed detailed pass/fail list):
========================================================
Kselftest Dependency Check for [./kselftest_deps.sh aarch64-linux-gnu-gcc ]
results...
========================================================
Checked tests defining LDLIBS dependencies
--------------------------------------------------------
Total tests with Dependencies:
55 Pass: 41 Fail: 14
--------------------------------------------------------
Targets failed build dependency check on system:
bpf capabilities filesystems futex gpio intel_pstate membarrier memfd
mqueue net powerpc ptp rseq rtc timens timers vDSO vm
--------------------------------------------------------
--------------------------------------------------------
Targets failed build dependency check on system:
bpf capabilities gpio memfd mqueue net netfilter safesetid vm
--------------------------------------------------------
Missing libraries system
-lcap -lcap-ng -lelf -lfuse -lmnl -lmount -lnuma -lpopt -lz
--------------------------------------------------------
========================================================

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Fix test errors related to lib.mk khdr target

Commit b2d35fa5fc80 ("selftests: add headers_install to lib.mk") added
khdr target to run headers_install target from the main Makefile. The
logic uses KSFT_KHDR_INSTALL and top_srcdir as controls to initialize
variables and include files to run headers_install from the top level
Makefile. There are a few problems with this logic.

1. Exposes top_srcdir to all tests
2. Common logic impacts all tests
3. Uses KSFT_KHDR_INSTALL, top_srcdir, and khdr in an adhoc way. Tests
add "khdr" dependency in their Makefiles to TEST_PROGS_EXTENDED in
some cases, and STATIC_LIBS in other cases. This makes this framework
confusing to use.

The common logic that runs for all tests even when KSFT_KHDR_INSTALL
isn't defined by the test. top_srcdir is initialized to a default value
when test doesn't initialize it. It works for all tests without a sub-dir
structure and tests with sub-dir structure fail to build.

e.g: make -C sparc64/drivers/ or make -C drivers/dma-buf

../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
make: *** No rule to make target '../../../../scripts/subarch.include'. Stop.

There is no reason to require all tests to define top_srcdir and there is
no need to require tests to add khdr dependency using adhoc changes to
TEST_* and other variables.

Fix it with a consistent use of KSFT_KHDR_INSTALL and top_srcdir from tests
that have the dependency on headers_install.

Change common logic to include khdr target define and "all" target with
dependency on khdr when KSFT_KHDR_INSTALL is defined.

Only tests that have dependency on headers_install have to define just
the KSFT_KHDR_INSTALL, and top_srcdir variables and there is no need to
specify khdr dependency in the test Makefiles.

Fixes: b2d35fa5fc80 ("selftests: add headers_install to lib.mk")
Cc: stable@vger.kernel.org
Signed-off-by: Shuah Khan <shuah@kernel.org>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Reviewed-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>

selftests: Fix test errors related to lib.mk khdr target

Commit b2d35fa5fc80 ("selftests: add headers_install to lib.mk") added
khdr target to run headers_install target from the main Makefile. The
logic uses KSFT_KHDR_INSTALL and top_srcdir as controls to initialize
variables and include files to run headers_install from the top level
Makefile. There are a few problems with this logic.

1. Exposes top_srcdir to all tests
2. Common logic impacts all tests
3. Uses KSFT_KHDR_INSTALL, top_srcdir, and khdr in an adhoc way. Tests
add "khdr" dependency in their Makefiles to TEST_PROGS_EXTENDED in
some cases, and STATIC_LIBS in other cases. This makes this framework
confusing to use.

The common logic that runs for all tests even when KSFT_KHDR_INSTALL
isn't defined by the test. top_srcdir is initialized to a default value
when test doesn't initialize it. It works for all tests without a sub-dir
structure and tests with sub-dir structure fail to build.

e.g: make -C sparc64/drivers/ or make -C drivers/dma-buf

../../lib.mk:20: ../../../../scripts/subarch.include: No such file or directory
make: *** No rule to make target '../../../../scripts/subarch.include'. Stop.

There is no reason to require all tests to define top_srcdir and there is
no need to require tests to add khdr dependency using adhoc changes to
TEST_* and other variables.

Fix it with a consistent use of KSFT_KHDR_INSTALL and top_srcdir from tests
that have the dependency on headers_install.

Change common logic to include khdr target define and "all" target with
dependency on khdr when KSFT_KHDR_INSTALL is defined.

Only tests that have dependency on headers_install have to define just
the KSFT_KHDR_INSTALL, and top_srcdir variables and there is no need to
specify khdr dependency in the test Makefiles.

Fixes: b2d35fa5fc80 ("selftests: add headers_install to lib.mk")
Cc: stable@vger.kernel.org
Signed-off-by: Shuah Khan <shuah@kernel.org>

selftests: gpio: Find libmount with pkg-config if available

If pkg-config is available, use it to define the CFLAGS and
LDLIBS needed for libmount; else, use the current hard-coded
paths and options.

Using pkg-config is very helpful for cross-compilation
environments, and is sometimes readily available on developer
boxes to ensure we get the right compiler/linker options for
the given package.

Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>

selftests: gpio: Fix OUTPUT directory in Makefile

When simply running `make' from the selftests top dir, this
error shows up:

cc -O2 -g -std=gnu99 -Wall -I../../../../usr/include/ -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/uuid gpio-mockup-chardev.c ../../../gpio/gpio-utils.o -lmount -o gpio-mockup-chardev
cc: error: ../../../gpio/gpio-utils.o: No such file or directory
<builtin>: recipe for target 'gpio-mockup-chardev' failed
make[1]: *** [gpio-mockup-chardev] Error 1

because the output directory is set to "selftests/gpio" and
all binaries built from ../../../gpio/ end up there. In fact,
they appear as, exempli gratia:
* gpiogpio-event-mon
* gpiogpio-hammer
* gpioinclude/
* gpiolsgpio
which is wrong, as it's missing a directory separator
somewhere.

This patch sets straight the output directory when building
../../../gpio/ so that binaries don't cross paths.

Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

selftests: gpio: restructure Makefile

This patch cleans up the Makefile by restructuring a couple of
things, namely:
1) change explicit paths in targets for variables
2) substitute a variable (BINARIES) for another, part of the
selftests build system (TEST_PROGS_EXTENDED)
3) proper cleaning up of the EXTRA objects

The resulting Makefile is much more readable and manageable.

Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

selftests: add headers_install to lib.mk

If the kernel headers aren't installed we can't build all the tests.
Add a new make target rule 'khdr' in the file lib.mk to generate the
kernel headers and that gets include for every test-dir Makefile that
includes lib.mk If the testdir in turn have its own sub-dirs the
top_srcdir needs to be set to the linux-rootdir to be able to generate
the kernel headers.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Fathi Boudra <fathi.boudra@linaro.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: gpio: fix clean target to remove all generated files and dirs

gpio test creates executables, object files, and include directory
under selftests directory. Enhance clean target to remove all files
it generates.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: gpio: override clean in lib.mk to fix warnings

Add override for lib.mk clean to fix the following warnings from clean
target run.

Makefile:11: warning: overriding recipe for target 'clean'
../lib.mk:55: warning: ignoring old recipe for target 'clean'

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftest/gpio: add gpio test case

This test script try to do whitebox testing for gpio subsystem(based on
gpiolib). It manipulate gpio device through chardev or sysfs and check
the result from debugfs. This script test gpio-mockup through chardev by
default. User could test other gpio chip by passing the module name.
Some of the testcases are turned off by default to avoid the conflicting
with gpiochip in system.

In details, it test the following things:
1. Test direction and output value for valid pin.
2. Test dynamic allocation of gpio base.
3. Add single, multi gpiochip to do overlap check.

Run "tools/testing/selftests/gpio/gpio-mockup.sh -h" for usage.

Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>