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 22:07:57 +08:00
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// SPDX-License-Identifier: GPL-2.0
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2022-02-22 20:23:24 +08:00
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2013-10-05 04:06:53 +08:00
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/*
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* Generic wait-for-completion handler;
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*
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* It differs from semaphores in that their default case is the opposite,
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* wait_for_completion default blocks whereas semaphore default non-block. The
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* interface also makes it easy to 'complete' multiple waiting threads,
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* something which isn't entirely natural for semaphores.
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*
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* But more importantly, the primitive documents the usage. Semaphores would
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* typically be used for exclusion which gives rise to priority inversion.
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* Waiting for completion is a typically sync point, but not an exclusion point.
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*/
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2023-03-08 15:31:58 +08:00
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static void complete_with_flags(struct completion *x, int wake_flags)
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{
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unsigned long flags;
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raw_spin_lock_irqsave(&x->wait.lock, flags);
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if (x->done != UINT_MAX)
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x->done++;
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swake_up_locked(&x->wait, wake_flags);
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raw_spin_unlock_irqrestore(&x->wait.lock, flags);
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}
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void complete_on_current_cpu(struct completion *x)
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{
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return complete_with_flags(x, WF_CURRENT_CPU);
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}
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2013-10-05 04:06:53 +08:00
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/**
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* complete: - signals a single thread waiting on this completion
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* @x: holds the state of this particular completion
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*
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* This will wake up a single thread waiting on this completion. Threads will be
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* awakened in the same order in which they were queued.
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*
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* See also complete_all(), wait_for_completion() and related routines.
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*
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2018-07-17 02:06:03 +08:00
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* If this function wakes up a task, it executes a full memory barrier before
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* accessing the task state.
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2013-10-05 04:06:53 +08:00
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*/
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void complete(struct completion *x)
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{
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2023-03-08 15:31:58 +08:00
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complete_with_flags(x, 0);
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2013-10-05 04:06:53 +08:00
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}
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EXPORT_SYMBOL(complete);
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/**
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* complete_all: - signals all threads waiting on this completion
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* @x: holds the state of this particular completion
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*
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* This will wake up all threads waiting on this particular completion event.
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*
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2018-07-17 02:06:03 +08:00
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* If this function wakes up a task, it executes a full memory barrier before
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* accessing the task state.
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2017-08-17 01:12:02 +08:00
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*
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* Since complete_all() sets the completion of @x permanently to done
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* to allow multiple waiters to finish, a call to reinit_completion()
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* must be used on @x if @x is to be used again. The code must make
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* sure that all waiters have woken and finished before reinitializing
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* @x. Also note that the function completion_done() can not be used
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* to know if there are still waiters after complete_all() has been called.
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2013-10-05 04:06:53 +08:00
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*/
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void complete_all(struct completion *x)
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{
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unsigned long flags;
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2020-03-23 23:20:19 +08:00
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lockdep_assert_RT_in_threaded_ctx();
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2020-03-21 19:26:00 +08:00
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raw_spin_lock_irqsave(&x->wait.lock, flags);
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2016-12-21 16:05:02 +08:00
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x->done = UINT_MAX;
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2020-03-21 19:26:00 +08:00
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swake_up_all_locked(&x->wait);
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raw_spin_unlock_irqrestore(&x->wait.lock, flags);
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2013-10-05 04:06:53 +08:00
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}
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EXPORT_SYMBOL(complete_all);
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static inline long __sched
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do_wait_for_common(struct completion *x,
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long (*action)(long), long timeout, int state)
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{
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if (!x->done) {
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2020-03-21 19:26:00 +08:00
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DECLARE_SWAITQUEUE(wait);
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2013-10-05 04:06:53 +08:00
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do {
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if (signal_pending_state(state, current)) {
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timeout = -ERESTARTSYS;
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break;
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}
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2020-03-21 19:26:00 +08:00
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__prepare_to_swait(&x->wait, &wait);
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2013-10-05 04:06:53 +08:00
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__set_current_state(state);
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2020-03-21 19:26:00 +08:00
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raw_spin_unlock_irq(&x->wait.lock);
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2013-10-05 04:06:53 +08:00
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timeout = action(timeout);
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2020-03-21 19:26:00 +08:00
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raw_spin_lock_irq(&x->wait.lock);
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2013-10-05 04:06:53 +08:00
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} while (!x->done && timeout);
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2020-03-21 19:26:00 +08:00
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__finish_swait(&x->wait, &wait);
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2013-10-05 04:06:53 +08:00
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if (!x->done)
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return timeout;
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}
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2016-12-21 16:05:02 +08:00
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if (x->done != UINT_MAX)
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x->done--;
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2013-10-05 04:06:53 +08:00
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return timeout ?: 1;
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}
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static inline long __sched
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__wait_for_common(struct completion *x,
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long (*action)(long), long timeout, int state)
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{
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might_sleep();
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2017-08-07 15:12:56 +08:00
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complete_acquire(x);
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2020-03-21 19:26:00 +08:00
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raw_spin_lock_irq(&x->wait.lock);
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2013-10-05 04:06:53 +08:00
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timeout = do_wait_for_common(x, action, timeout, state);
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2020-03-21 19:26:00 +08:00
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raw_spin_unlock_irq(&x->wait.lock);
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2017-08-07 15:12:56 +08:00
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complete_release(x);
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2013-10-05 04:06:53 +08:00
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return timeout;
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}
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static long __sched
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wait_for_common(struct completion *x, long timeout, int state)
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{
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return __wait_for_common(x, schedule_timeout, timeout, state);
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}
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static long __sched
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wait_for_common_io(struct completion *x, long timeout, int state)
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{
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return __wait_for_common(x, io_schedule_timeout, timeout, state);
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}
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/**
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* wait_for_completion: - waits for completion of a task
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* @x: holds the state of this particular completion
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*
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* This waits to be signaled for completion of a specific task. It is NOT
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* interruptible and there is no timeout.
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*
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* See also similar routines (i.e. wait_for_completion_timeout()) with timeout
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* and interrupt capability. Also see complete().
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*/
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void __sched wait_for_completion(struct completion *x)
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{
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wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
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}
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EXPORT_SYMBOL(wait_for_completion);
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/**
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* wait_for_completion_timeout: - waits for completion of a task (w/timeout)
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* @x: holds the state of this particular completion
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* @timeout: timeout value in jiffies
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*
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* This waits for either a completion of a specific task to be signaled or for a
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* specified timeout to expire. The timeout is in jiffies. It is not
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* interruptible.
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*
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* Return: 0 if timed out, and positive (at least 1, or number of jiffies left
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* till timeout) if completed.
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*/
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unsigned long __sched
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wait_for_completion_timeout(struct completion *x, unsigned long timeout)
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{
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return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE);
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}
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EXPORT_SYMBOL(wait_for_completion_timeout);
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/**
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* wait_for_completion_io: - waits for completion of a task
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* @x: holds the state of this particular completion
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*
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* This waits to be signaled for completion of a specific task. It is NOT
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* interruptible and there is no timeout. The caller is accounted as waiting
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2014-11-04 19:01:41 +08:00
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* for IO (which traditionally means blkio only).
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2013-10-05 04:06:53 +08:00
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*/
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void __sched wait_for_completion_io(struct completion *x)
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{
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wait_for_common_io(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
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}
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EXPORT_SYMBOL(wait_for_completion_io);
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/**
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* wait_for_completion_io_timeout: - waits for completion of a task (w/timeout)
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* @x: holds the state of this particular completion
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* @timeout: timeout value in jiffies
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*
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* This waits for either a completion of a specific task to be signaled or for a
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* specified timeout to expire. The timeout is in jiffies. It is not
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2014-11-04 19:01:41 +08:00
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* interruptible. The caller is accounted as waiting for IO (which traditionally
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* means blkio only).
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2013-10-05 04:06:53 +08:00
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*
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* Return: 0 if timed out, and positive (at least 1, or number of jiffies left
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* till timeout) if completed.
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*/
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unsigned long __sched
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wait_for_completion_io_timeout(struct completion *x, unsigned long timeout)
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{
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return wait_for_common_io(x, timeout, TASK_UNINTERRUPTIBLE);
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}
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EXPORT_SYMBOL(wait_for_completion_io_timeout);
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/**
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* wait_for_completion_interruptible: - waits for completion of a task (w/intr)
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* @x: holds the state of this particular completion
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*
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* This waits for completion of a specific task to be signaled. It is
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* interruptible.
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*
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* Return: -ERESTARTSYS if interrupted, 0 if completed.
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*/
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int __sched wait_for_completion_interruptible(struct completion *x)
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{
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long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE);
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2022-08-22 19:18:20 +08:00
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2013-10-05 04:06:53 +08:00
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if (t == -ERESTARTSYS)
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return t;
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return 0;
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}
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EXPORT_SYMBOL(wait_for_completion_interruptible);
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/**
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* wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr))
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* @x: holds the state of this particular completion
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* @timeout: timeout value in jiffies
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*
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* This waits for either a completion of a specific task to be signaled or for a
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* specified timeout to expire. It is interruptible. The timeout is in jiffies.
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*
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* Return: -ERESTARTSYS if interrupted, 0 if timed out, positive (at least 1,
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* or number of jiffies left till timeout) if completed.
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*/
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long __sched
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wait_for_completion_interruptible_timeout(struct completion *x,
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unsigned long timeout)
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{
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return wait_for_common(x, timeout, TASK_INTERRUPTIBLE);
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}
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EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
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/**
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* wait_for_completion_killable: - waits for completion of a task (killable)
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* @x: holds the state of this particular completion
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*
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* This waits to be signaled for completion of a specific task. It can be
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* interrupted by a kill signal.
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*
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* Return: -ERESTARTSYS if interrupted, 0 if completed.
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*/
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int __sched wait_for_completion_killable(struct completion *x)
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{
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long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
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2022-08-22 19:18:20 +08:00
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2013-10-05 04:06:53 +08:00
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if (t == -ERESTARTSYS)
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return t;
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return 0;
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}
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EXPORT_SYMBOL(wait_for_completion_killable);
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2022-08-22 19:18:20 +08:00
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int __sched wait_for_completion_state(struct completion *x, unsigned int state)
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{
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long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, state);
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if (t == -ERESTARTSYS)
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return t;
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return 0;
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}
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EXPORT_SYMBOL(wait_for_completion_state);
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2013-10-05 04:06:53 +08:00
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/**
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* wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable))
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* @x: holds the state of this particular completion
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* @timeout: timeout value in jiffies
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*
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* This waits for either a completion of a specific task to be
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* signaled or for a specified timeout to expire. It can be
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* interrupted by a kill signal. The timeout is in jiffies.
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*
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* Return: -ERESTARTSYS if interrupted, 0 if timed out, positive (at least 1,
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* or number of jiffies left till timeout) if completed.
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*/
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long __sched
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wait_for_completion_killable_timeout(struct completion *x,
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|
unsigned long timeout)
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|
{
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return wait_for_common(x, timeout, TASK_KILLABLE);
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}
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EXPORT_SYMBOL(wait_for_completion_killable_timeout);
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/**
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* try_wait_for_completion - try to decrement a completion without blocking
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* @x: completion structure
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*
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* Return: 0 if a decrement cannot be done without blocking
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* 1 if a decrement succeeded.
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*
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* If a completion is being used as a counting completion,
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* attempt to decrement the counter without blocking. This
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* enables us to avoid waiting if the resource the completion
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* is protecting is not available.
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|
*/
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|
|
bool try_wait_for_completion(struct completion *x)
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|
{
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|
unsigned long flags;
|
2018-02-21 20:54:07 +08:00
|
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|
bool ret = true;
|
2013-10-05 04:06:53 +08:00
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|
2015-01-23 19:41:47 +08:00
|
|
|
/*
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|
|
|
* Since x->done will need to be locked only
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|
* in the non-blocking case, we check x->done
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|
* first without taking the lock so we can
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|
|
* return early in the blocking case.
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|
*/
|
2015-02-13 03:59:13 +08:00
|
|
|
if (!READ_ONCE(x->done))
|
2018-02-21 20:54:07 +08:00
|
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|
return false;
|
2015-01-23 19:41:47 +08:00
|
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|
|
2020-03-21 19:26:00 +08:00
|
|
|
raw_spin_lock_irqsave(&x->wait.lock, flags);
|
2013-10-05 04:06:53 +08:00
|
|
|
if (!x->done)
|
2018-02-21 20:54:07 +08:00
|
|
|
ret = false;
|
2016-12-21 16:05:02 +08:00
|
|
|
else if (x->done != UINT_MAX)
|
2013-10-05 04:06:53 +08:00
|
|
|
x->done--;
|
2020-03-21 19:26:00 +08:00
|
|
|
raw_spin_unlock_irqrestore(&x->wait.lock, flags);
|
2013-10-05 04:06:53 +08:00
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(try_wait_for_completion);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* completion_done - Test to see if a completion has any waiters
|
|
|
|
* @x: completion structure
|
|
|
|
*
|
|
|
|
* Return: 0 if there are waiters (wait_for_completion() in progress)
|
|
|
|
* 1 if there are no waiters.
|
|
|
|
*
|
2017-08-17 01:12:02 +08:00
|
|
|
* Note, this will always return true if complete_all() was called on @X.
|
2013-10-05 04:06:53 +08:00
|
|
|
*/
|
|
|
|
bool completion_done(struct completion *x)
|
|
|
|
{
|
2017-06-30 03:47:04 +08:00
|
|
|
unsigned long flags;
|
|
|
|
|
2015-02-13 03:59:13 +08:00
|
|
|
if (!READ_ONCE(x->done))
|
|
|
|
return false;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If ->done, we need to wait for complete() to release ->wait.lock
|
|
|
|
* otherwise we can end up freeing the completion before complete()
|
|
|
|
* is done referencing it.
|
|
|
|
*/
|
2020-03-21 19:26:00 +08:00
|
|
|
raw_spin_lock_irqsave(&x->wait.lock, flags);
|
|
|
|
raw_spin_unlock_irqrestore(&x->wait.lock, flags);
|
2015-02-13 03:59:13 +08:00
|
|
|
return true;
|
2013-10-05 04:06:53 +08:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(completion_done);
|