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>
2017-11-01 14:07:57 +00:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2011-07-20 15:38:57 +00:00
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#ifndef __LINUX_KCONFIG_H
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#define __LINUX_KCONFIG_H
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2020-04-23 14:23:52 +00:00
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/* CONFIG_CC_VERSION_TEXT (Do not delete this comment. See help in Kconfig) */
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2011-07-20 15:38:57 +00:00
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#include <generated/autoconf.h>
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Kbuild: always define endianess in kconfig.h
Build testing with LTO found a couple of files that get compiled
differently depending on whether asm/byteorder.h gets included early
enough or not. In particular, include/asm-generic/qrwlock_types.h is
affected by this, but there are probably others as well.
The symptom is a series of LTO link time warnings, including these:
net/netlabel/netlabel_unlabeled.h:223: error: type of 'netlbl_unlhsh_add' does not match original declaration [-Werror=lto-type-mismatch]
int netlbl_unlhsh_add(struct net *net,
net/netlabel/netlabel_unlabeled.c:377: note: 'netlbl_unlhsh_add' was previously declared here
include/net/ipv6.h:360: error: type of 'ipv6_renew_options_kern' does not match original declaration [-Werror=lto-type-mismatch]
ipv6_renew_options_kern(struct sock *sk,
net/ipv6/exthdrs.c:1162: note: 'ipv6_renew_options_kern' was previously declared here
net/core/dev.c:761: note: 'dev_get_by_name_rcu' was previously declared here
struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
net/core/dev.c:761: note: code may be misoptimized unless -fno-strict-aliasing is used
drivers/gpu/drm/i915/i915_drv.h:3377: error: type of 'i915_gem_object_set_to_wc_domain' does not match original declaration [-Werror=lto-type-mismatch]
i915_gem_object_set_to_wc_domain(struct drm_i915_gem_object *obj, bool write);
drivers/gpu/drm/i915/i915_gem.c:3639: note: 'i915_gem_object_set_to_wc_domain' was previously declared here
include/linux/debugfs.h:92:9: error: type of 'debugfs_attr_read' does not match original declaration [-Werror=lto-type-mismatch]
ssize_t debugfs_attr_read(struct file *file, char __user *buf,
fs/debugfs/file.c:318: note: 'debugfs_attr_read' was previously declared here
include/linux/rwlock_api_smp.h:30: error: type of '_raw_read_unlock' does not match original declaration [-Werror=lto-type-mismatch]
void __lockfunc _raw_read_unlock(rwlock_t *lock) __releases(lock);
kernel/locking/spinlock.c:246:26: note: '_raw_read_unlock' was previously declared here
include/linux/fs.h:3308:5: error: type of 'simple_attr_open' does not match original declaration [-Werror=lto-type-mismatch]
int simple_attr_open(struct inode *inode, struct file *file,
fs/libfs.c:795: note: 'simple_attr_open' was previously declared here
All of the above are caused by include/asm-generic/qrwlock_types.h
failing to include asm/byteorder.h after commit e0d02285f16e
("locking/qrwlock: Use 'struct qrwlock' instead of 'struct __qrwlock'")
in linux-4.15.
Similar bugs may or may not exist in older kernels as well, but there is
no easy way to test those with link-time optimizations, and kernels
before 4.14 are harder to fix because they don't have Babu's patch
series
We had similar issues with CONFIG_ symbols in the past and ended up
always including the configuration headers though linux/kconfig.h. This
works around the issue through that same file, defining either
__BIG_ENDIAN or __LITTLE_ENDIAN depending on CONFIG_CPU_BIG_ENDIAN,
which is now always set on all architectures since commit 4c97a0c8fee3
("arch: define CPU_BIG_ENDIAN for all fixed big endian archs").
Link: http://lkml.kernel.org/r/20180202154104.1522809-2-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Babu Moger <babu.moger@amd.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-21 22:45:20 +00:00
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#ifdef CONFIG_CPU_BIG_ENDIAN
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#define __BIG_ENDIAN 4321
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#else
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#define __LITTLE_ENDIAN 1234
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#endif
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kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
The typical usage of IS_ENABLED() is
if (IS_ENABLED(CONFIG_FOO)) {
...
}
or
#if IS_ENABLED(CONFIG_FOO)
...
#endif
The current implementation of IS_ENABLED() includes "||" operator,
which works well in those expressions like above.
However, there is a case where we want to evaluate a config option
beyond those use cases.
For example, the OF_TABLE() in include/asm-generic/vmlinux.lds.h
needs to evaluate a config option in macro expansion:
#define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name)
#define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name)
#define OF_TABLE(cfg, name) __OF_TABLE(config_enabled(cfg), name)
#define _OF_TABLE_0(name)
#define _OF_TABLE_1(name) \
...
Here, we can not use IS_ENABLED() because of the "||" operator in
its define. It is true config_enabled() works well, but it is a bit
ambiguous to be used against config options.
This commit makes IS_ENABLED() available in more generic context by
calculating "or" with macro expansion only.
Do likewise for IS_REACHABLE().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-14 05:58:57 +00:00
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#define __ARG_PLACEHOLDER_1 0,
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#define __take_second_arg(__ignored, val, ...) val
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/*
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* The use of "&&" / "||" is limited in certain expressions.
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2017-02-27 22:29:56 +00:00
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* The following enable to calculate "and" / "or" with macro expansion only.
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kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
The typical usage of IS_ENABLED() is
if (IS_ENABLED(CONFIG_FOO)) {
...
}
or
#if IS_ENABLED(CONFIG_FOO)
...
#endif
The current implementation of IS_ENABLED() includes "||" operator,
which works well in those expressions like above.
However, there is a case where we want to evaluate a config option
beyond those use cases.
For example, the OF_TABLE() in include/asm-generic/vmlinux.lds.h
needs to evaluate a config option in macro expansion:
#define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name)
#define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name)
#define OF_TABLE(cfg, name) __OF_TABLE(config_enabled(cfg), name)
#define _OF_TABLE_0(name)
#define _OF_TABLE_1(name) \
...
Here, we can not use IS_ENABLED() because of the "||" operator in
its define. It is true config_enabled() works well, but it is a bit
ambiguous to be used against config options.
This commit makes IS_ENABLED() available in more generic context by
calculating "or" with macro expansion only.
Do likewise for IS_REACHABLE().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-14 05:58:57 +00:00
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*/
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#define __and(x, y) ___and(x, y)
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#define ___and(x, y) ____and(__ARG_PLACEHOLDER_##x, y)
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#define ____and(arg1_or_junk, y) __take_second_arg(arg1_or_junk y, 0)
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#define __or(x, y) ___or(x, y)
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#define ___or(x, y) ____or(__ARG_PLACEHOLDER_##x, y)
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#define ____or(arg1_or_junk, y) __take_second_arg(arg1_or_junk 1, y)
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2011-07-20 15:38:57 +00:00
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/*
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2012-04-12 23:46:32 +00:00
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* Helper macros to use CONFIG_ options in C/CPP expressions. Note that
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2011-07-20 15:38:57 +00:00
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* these only work with boolean and tristate options.
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*/
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2012-04-12 23:46:32 +00:00
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/*
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* Getting something that works in C and CPP for an arg that may or may
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* not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
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* we match on the placeholder define, insert the "0," for arg1 and generate
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* the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
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* When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
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* the last step cherry picks the 2nd arg, we get a zero.
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*/
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2016-06-14 05:58:54 +00:00
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#define __is_defined(x) ___is_defined(x)
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#define ___is_defined(val) ____is_defined(__ARG_PLACEHOLDER_##val)
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#define ____is_defined(arg1_or_junk) __take_second_arg(arg1_or_junk 1, 0)
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2012-04-12 23:46:32 +00:00
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2011-07-20 15:38:57 +00:00
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/*
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* IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
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* otherwise. For boolean options, this is equivalent to
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* IS_ENABLED(CONFIG_FOO).
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*/
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kconfig.h: remove config_enabled() macro
The use of config_enabled() is ambiguous. For config options,
IS_ENABLED(), IS_REACHABLE(), etc. will make intention clearer.
Sometimes config_enabled() has been used for non-config options because
it is useful to check whether the given symbol is defined or not.
I have been tackling on deprecating config_enabled(), and now is the
time to finish this work.
Some new users have appeared for v4.9-rc1, but it is trivial to replace
them:
- arch/x86/mm/kaslr.c
replace config_enabled() with IS_ENABLED() because
CONFIG_X86_ESPFIX64 and CONFIG_EFI are boolean.
- include/asm-generic/export.h
replace config_enabled() with __is_defined().
Then, config_enabled() can be removed now.
Going forward, please use IS_ENABLED(), IS_REACHABLE(), etc. for config
options, and __is_defined() for non-config symbols.
Link: http://lkml.kernel.org/r/1476616078-32252-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-28 00:46:38 +00:00
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#define IS_BUILTIN(option) __is_defined(option)
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2011-07-20 15:38:57 +00:00
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/*
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* IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
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* otherwise.
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*/
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kconfig.h: remove config_enabled() macro
The use of config_enabled() is ambiguous. For config options,
IS_ENABLED(), IS_REACHABLE(), etc. will make intention clearer.
Sometimes config_enabled() has been used for non-config options because
it is useful to check whether the given symbol is defined or not.
I have been tackling on deprecating config_enabled(), and now is the
time to finish this work.
Some new users have appeared for v4.9-rc1, but it is trivial to replace
them:
- arch/x86/mm/kaslr.c
replace config_enabled() with IS_ENABLED() because
CONFIG_X86_ESPFIX64 and CONFIG_EFI are boolean.
- include/asm-generic/export.h
replace config_enabled() with __is_defined().
Then, config_enabled() can be removed now.
Going forward, please use IS_ENABLED(), IS_REACHABLE(), etc. for config
options, and __is_defined() for non-config symbols.
Link: http://lkml.kernel.org/r/1476616078-32252-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-28 00:46:38 +00:00
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#define IS_MODULE(option) __is_defined(option##_MODULE)
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2011-07-20 15:38:57 +00:00
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2015-02-18 17:12:42 +00:00
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/*
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* IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
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* code can call a function defined in code compiled based on CONFIG_FOO.
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* This is similar to IS_ENABLED(), but returns false when invoked from
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* built-in code when CONFIG_FOO is set to 'm'.
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*/
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kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
The typical usage of IS_ENABLED() is
if (IS_ENABLED(CONFIG_FOO)) {
...
}
or
#if IS_ENABLED(CONFIG_FOO)
...
#endif
The current implementation of IS_ENABLED() includes "||" operator,
which works well in those expressions like above.
However, there is a case where we want to evaluate a config option
beyond those use cases.
For example, the OF_TABLE() in include/asm-generic/vmlinux.lds.h
needs to evaluate a config option in macro expansion:
#define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name)
#define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name)
#define OF_TABLE(cfg, name) __OF_TABLE(config_enabled(cfg), name)
#define _OF_TABLE_0(name)
#define _OF_TABLE_1(name) \
...
Here, we can not use IS_ENABLED() because of the "||" operator in
its define. It is true config_enabled() works well, but it is a bit
ambiguous to be used against config options.
This commit makes IS_ENABLED() available in more generic context by
calculating "or" with macro expansion only.
Do likewise for IS_REACHABLE().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-14 05:58:57 +00:00
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#define IS_REACHABLE(option) __or(IS_BUILTIN(option), \
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__and(IS_MODULE(option), __is_defined(MODULE)))
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2015-02-18 17:12:42 +00:00
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2015-04-16 19:48:38 +00:00
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/*
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* IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
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* 0 otherwise.
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*/
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kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
The typical usage of IS_ENABLED() is
if (IS_ENABLED(CONFIG_FOO)) {
...
}
or
#if IS_ENABLED(CONFIG_FOO)
...
#endif
The current implementation of IS_ENABLED() includes "||" operator,
which works well in those expressions like above.
However, there is a case where we want to evaluate a config option
beyond those use cases.
For example, the OF_TABLE() in include/asm-generic/vmlinux.lds.h
needs to evaluate a config option in macro expansion:
#define ___OF_TABLE(cfg, name) _OF_TABLE_##cfg(name)
#define __OF_TABLE(cfg, name) ___OF_TABLE(cfg, name)
#define OF_TABLE(cfg, name) __OF_TABLE(config_enabled(cfg), name)
#define _OF_TABLE_0(name)
#define _OF_TABLE_1(name) \
...
Here, we can not use IS_ENABLED() because of the "||" operator in
its define. It is true config_enabled() works well, but it is a bit
ambiguous to be used against config options.
This commit makes IS_ENABLED() available in more generic context by
calculating "or" with macro expansion only.
Do likewise for IS_REACHABLE().
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-14 05:58:57 +00:00
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#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
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2015-04-16 19:48:38 +00:00
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kconfig.h: Add IF_ENABLED() macro
IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is set to 'y'
or 'm', NULL otherwise. The (ptr) argument must be a pointer.
The IF_ENABLED() macro can be very useful to help GCC drop dead code.
For instance, consider the following:
#ifdef CONFIG_FOO_SUSPEND
static int foo_suspend(struct device *dev)
{
...
}
#endif
static struct pm_ops foo_ops = {
#ifdef CONFIG_FOO_SUSPEND
.suspend = foo_suspend,
#endif
};
While this works, the foo_suspend() macro is compiled conditionally,
only when CONFIG_FOO_SUSPEND is set. This is problematic, as there could
be a build bug in this function, we wouldn't have a way to know unless
the config option is set.
An alternative is to declare foo_suspend() always, but mark it as maybe
unused:
static int __maybe_unused foo_suspend(struct device *dev)
{
...
}
static struct pm_ops foo_ops = {
#ifdef CONFIG_FOO_SUSPEND
.suspend = foo_suspend,
#endif
};
Again, this works, but the __maybe_unused attribute is required to
instruct the compiler that the function may not be referenced anywhere,
and is safe to remove without making a fuss about it. This makes the
programmer responsible for tagging the functions that can be
garbage-collected.
With this patch, it is now possible to write the following:
static int foo_suspend(struct device *dev)
{
...
}
static struct pm_ops foo_ops = {
.suspend = IF_ENABLED(CONFIG_FOO_SUSPEND, foo_suspend),
};
The foo_suspend() function will now be automatically dropped by the
compiler, and it does not require any specific attribute.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201213235447.138271-1-paul@crapouillou.net
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-12-13 23:54:46 +00:00
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/*
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* IF_ENABLED(CONFIG_FOO, ptr) evaluates to (ptr) if CONFIG_FOO is set to 'y'
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* or 'm', NULL otherwise.
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*/
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#define IF_ENABLED(option, ptr) (IS_ENABLED(option) ? (ptr) : NULL)
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2011-07-20 15:38:57 +00:00
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#endif /* __LINUX_KCONFIG_H */
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