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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2008-07-18 12:55:51 +08:00
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/* thread_info.h: sparc64 low-level thread information
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*
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* Copyright (C) 2002 David S. Miller (davem@redhat.com)
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*/
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#ifndef _ASM_THREAD_INFO_H
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#define _ASM_THREAD_INFO_H
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#ifdef __KERNEL__
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#define NSWINS 7
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#define TI_FLAG_BYTE_FAULT_CODE 0
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#define TI_FLAG_FAULT_CODE_SHIFT 56
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#define TI_FLAG_BYTE_WSTATE 1
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#define TI_FLAG_WSTATE_SHIFT 48
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2012-09-26 13:21:14 +08:00
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#define TI_FLAG_BYTE_NOERROR 2
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#define TI_FLAG_BYTE_NOERROR_SHIFT 40
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#define TI_FLAG_BYTE_FPDEPTH 3
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#define TI_FLAG_FPDEPTH_SHIFT 32
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#define TI_FLAG_BYTE_CWP 4
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#define TI_FLAG_CWP_SHIFT 24
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2008-07-18 12:55:51 +08:00
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#define TI_FLAG_BYTE_WSAVED 5
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#define TI_FLAG_WSAVED_SHIFT 16
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#include <asm/page.h>
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#ifndef __ASSEMBLY__
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#include <asm/ptrace.h>
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#include <asm/types.h>
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struct task_struct;
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struct thread_info {
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/* D$ line 1 */
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struct task_struct *task;
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unsigned long flags;
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__u8 fpsaved[7];
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__u8 status;
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unsigned long ksp;
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/* D$ line 2 */
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unsigned long fault_address;
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struct pt_regs *kregs;
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int preempt_count; /* 0 => preemptable, <0 => BUG */
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__u8 new_child;
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2012-09-26 13:21:14 +08:00
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__u8 current_ds;
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2008-07-18 12:55:51 +08:00
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__u16 cpu;
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unsigned long *utraps;
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struct reg_window reg_window[NSWINS];
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unsigned long rwbuf_stkptrs[NSWINS];
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unsigned long gsr[7];
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unsigned long xfsr[7];
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struct pt_regs *kern_una_regs;
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unsigned int kern_una_insn;
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2014-10-19 11:12:33 +08:00
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unsigned long fpregs[(7 * 256) / sizeof(unsigned long)]
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__attribute__ ((aligned(64)));
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2008-07-18 12:55:51 +08:00
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};
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#endif /* !(__ASSEMBLY__) */
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/* offsets into the thread_info struct for assembly code access */
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#define TI_TASK 0x00000000
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#define TI_FLAGS 0x00000008
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#define TI_FAULT_CODE (TI_FLAGS + TI_FLAG_BYTE_FAULT_CODE)
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#define TI_WSTATE (TI_FLAGS + TI_FLAG_BYTE_WSTATE)
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#define TI_CWP (TI_FLAGS + TI_FLAG_BYTE_CWP)
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#define TI_FPDEPTH (TI_FLAGS + TI_FLAG_BYTE_FPDEPTH)
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#define TI_WSAVED (TI_FLAGS + TI_FLAG_BYTE_WSAVED)
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2012-09-26 13:21:14 +08:00
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#define TI_SYS_NOERROR (TI_FLAGS + TI_FLAG_BYTE_NOERROR)
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2008-07-18 12:55:51 +08:00
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#define TI_FPSAVED 0x00000010
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#define TI_KSP 0x00000018
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#define TI_FAULT_ADDR 0x00000020
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#define TI_KREGS 0x00000028
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2014-07-13 23:39:47 +08:00
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#define TI_PRE_COUNT 0x00000030
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#define TI_NEW_CHILD 0x00000034
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#define TI_CURRENT_DS 0x00000035
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#define TI_CPU 0x00000036
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#define TI_UTRAPS 0x00000038
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#define TI_REG_WINDOW 0x00000040
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#define TI_RWIN_SPTRS 0x000003c0
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#define TI_GSR 0x000003f8
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#define TI_XFSR 0x00000430
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#define TI_KUNA_REGS 0x00000468
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#define TI_KUNA_INSN 0x00000470
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2015-02-13 07:01:14 +08:00
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#define TI_FPREGS 0x00000480
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2008-07-18 12:55:51 +08:00
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/* We embed this in the uppermost byte of thread_info->flags */
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#define FAULT_CODE_WRITE 0x01 /* Write access, implies D-TLB */
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#define FAULT_CODE_DTLB 0x02 /* Miss happened in D-TLB */
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#define FAULT_CODE_ITLB 0x04 /* Miss happened in I-TLB */
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#define FAULT_CODE_WINFIXUP 0x08 /* Miss happened during spill/fill */
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#define FAULT_CODE_BLKCOMMIT 0x10 /* Use blk-commit ASI in copy_page */
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2014-09-16 21:26:47 +08:00
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#define FAULT_CODE_BAD_RA 0x20 /* Bad RA for sun4v */
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2008-07-18 12:55:51 +08:00
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#if PAGE_SHIFT == 13
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#define THREAD_SIZE (2*PAGE_SIZE)
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#define THREAD_SHIFT (PAGE_SHIFT + 1)
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#else /* PAGE_SHIFT == 13 */
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#define THREAD_SIZE PAGE_SIZE
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#define THREAD_SHIFT PAGE_SHIFT
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#endif /* PAGE_SHIFT == 13 */
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/*
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* macros/functions for gaining access to the thread information structure
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*/
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#ifndef __ASSEMBLY__
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#define INIT_THREAD_INFO(tsk) \
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{ \
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.task = &tsk, \
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2012-09-26 13:21:14 +08:00
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.current_ds = ASI_P, \
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2009-07-10 20:57:56 +08:00
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.preempt_count = INIT_PREEMPT_COUNT, \
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2008-07-18 12:55:51 +08:00
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}
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/* how to get the thread information struct from C */
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2018-10-22 13:36:17 +08:00
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#ifndef BUILD_VDSO
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2008-07-18 12:55:51 +08:00
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register struct thread_info *current_thread_info_reg asm("g6");
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#define current_thread_info() (current_thread_info_reg)
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2018-10-22 13:36:17 +08:00
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#else
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extern struct thread_info *current_thread_info(void);
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#endif
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2008-07-18 12:55:51 +08:00
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/* thread information allocation */
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#if PAGE_SHIFT == 13
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2012-05-05 23:05:47 +08:00
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#define THREAD_SIZE_ORDER 1
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2008-07-18 12:55:51 +08:00
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#else /* PAGE_SHIFT == 13 */
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2012-05-05 23:05:47 +08:00
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#define THREAD_SIZE_ORDER 0
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2008-07-18 12:55:51 +08:00
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#endif /* PAGE_SHIFT == 13 */
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#define __thread_flag_byte_ptr(ti) \
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((unsigned char *)(&((ti)->flags)))
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#define __cur_thread_flag_byte_ptr __thread_flag_byte_ptr(current_thread_info())
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#define get_thread_fault_code() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FAULT_CODE])
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#define set_thread_fault_code(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FAULT_CODE] = (val))
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#define get_thread_wstate() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_WSTATE])
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#define set_thread_wstate(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_WSTATE] = (val))
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#define get_thread_cwp() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_CWP])
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#define set_thread_cwp(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_CWP] = (val))
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2012-09-26 13:21:14 +08:00
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#define get_thread_noerror() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_NOERROR])
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#define set_thread_noerror(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_NOERROR] = (val))
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2008-07-18 12:55:51 +08:00
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#define get_thread_fpdepth() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FPDEPTH])
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#define set_thread_fpdepth(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_FPDEPTH] = (val))
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#define get_thread_wsaved() (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_WSAVED])
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#define set_thread_wsaved(val) (__cur_thread_flag_byte_ptr[TI_FLAG_BYTE_WSAVED] = (val))
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#endif /* !(__ASSEMBLY__) */
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/*
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* Thread information flags, only 16 bits are available as we encode
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* other values into the upper 6 bytes.
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*
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* On trap return we need to test several values:
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*
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2010-03-04 00:08:49 +08:00
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* user: need_resched, notify_resume, sigpending, wsaved
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2008-07-18 12:55:51 +08:00
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* kernel: fpdepth
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*
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* So to check for work in the kernel case we simply load the fpdepth
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* byte out of the flags and test it. For the user case we encode the
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* lower 3 bytes of flags as follows:
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* ----------------------------------------
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* | wsaved | flags byte 1 | flags byte 2 |
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* ----------------------------------------
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* This optimizes the user test into:
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* ldx [%g6 + TI_FLAGS], REG1
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* sethi %hi(_TIF_USER_WORK_MASK), REG2
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* or REG2, %lo(_TIF_USER_WORK_MASK), REG2
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* andcc REG1, REG2, %g0
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* be,pt no_work_to_do
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* nop
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*/
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#define TIF_SYSCALL_TRACE 0 /* syscall trace active */
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2008-04-21 06:06:49 +08:00
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#define TIF_NOTIFY_RESUME 1 /* callback before returning to user */
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2008-07-18 12:55:51 +08:00
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#define TIF_SIGPENDING 2 /* signal pending */
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#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
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2010-03-04 00:08:49 +08:00
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/* flag bit 4 is available */
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2008-07-18 12:55:51 +08:00
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#define TIF_UNALIGNED 5 /* allowed to do unaligned accesses */
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2016-10-13 12:36:13 +08:00
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#define TIF_UPROBE 6 /* breakpointed or singlestepped */
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2008-07-18 12:55:51 +08:00
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#define TIF_32BIT 7 /* 32-bit binary */
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2013-09-14 20:02:11 +08:00
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#define TIF_NOHZ 8 /* in adaptive nohz mode */
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2008-07-18 12:55:51 +08:00
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#define TIF_SECCOMP 9 /* secure computing */
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#define TIF_SYSCALL_AUDIT 10 /* syscall auditing active */
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2009-12-11 16:44:47 +08:00
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#define TIF_SYSCALL_TRACEPOINT 11 /* syscall tracepoint instrumentation */
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2008-07-18 12:55:51 +08:00
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/* NOTE: Thread flags >= 12 should be ones we have no interest
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* in using in assembly, else we can't use the mask as
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* an immediate value in instructions such as andcc.
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*/
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2018-02-24 06:46:41 +08:00
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#define TIF_MCDPER 12 /* Precise MCD exception */
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2010-05-14 17:13:27 +08:00
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#define TIF_MEMDIE 13 /* is terminating due to OOM killer */
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2008-07-18 12:55:51 +08:00
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#define TIF_POLLING_NRFLAG 14
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#define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE)
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2008-04-21 06:06:49 +08:00
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#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
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2008-07-18 12:55:51 +08:00
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#define _TIF_SIGPENDING (1<<TIF_SIGPENDING)
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#define _TIF_NEED_RESCHED (1<<TIF_NEED_RESCHED)
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#define _TIF_UNALIGNED (1<<TIF_UNALIGNED)
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2016-10-13 12:36:13 +08:00
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#define _TIF_UPROBE (1<<TIF_UPROBE)
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2008-07-18 12:55:51 +08:00
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#define _TIF_32BIT (1<<TIF_32BIT)
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2013-09-14 20:02:11 +08:00
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#define _TIF_NOHZ (1<<TIF_NOHZ)
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2008-07-18 12:55:51 +08:00
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#define _TIF_SECCOMP (1<<TIF_SECCOMP)
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#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
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2009-12-11 16:44:47 +08:00
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#define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT)
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2008-07-18 12:55:51 +08:00
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#define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG)
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#define _TIF_USER_WORK_MASK ((0xff << TI_FLAG_WSAVED_SHIFT) | \
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2008-04-21 06:06:49 +08:00
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_TIF_DO_NOTIFY_RESUME_MASK | \
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2010-03-04 00:08:49 +08:00
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_TIF_NEED_RESCHED)
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2016-10-13 12:36:13 +08:00
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#define _TIF_DO_NOTIFY_RESUME_MASK (_TIF_NOTIFY_RESUME | \
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_TIF_SIGPENDING | _TIF_UPROBE)
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2008-07-18 12:55:51 +08:00
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2014-04-23 00:39:51 +08:00
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#define is_32bit_task() (test_thread_flag(TIF_32BIT))
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2008-07-18 12:55:51 +08:00
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/*
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* Thread-synchronous status.
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*
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* This is different from the flags in that nobody else
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* ever touches our thread-synchronous status, so we don't
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* have to worry about atomic accesses.
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*
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* Note that there are only 8 bits available.
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*/
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#ifndef __ASSEMBLY__
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2012-06-02 02:22:01 +08:00
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sparc64: Make montmul/montsqr/mpmul usable in 32-bit threads.
The Montgomery Multiply, Montgomery Square, and Multiple-Precision
Multiply instructions work by loading a combination of the floating
point and multiple register windows worth of integer registers
with the inputs.
These values are 64-bit. But for 32-bit userland processes we only
save the low 32-bits of each integer register during a register spill.
This is because the register window save area is in the user stack and
has a fixed layout.
Therefore, the only way to use these instruction in 32-bit mode is to
perform the following sequence:
1) Load the top-32bits of a choosen integer register with a sentinel,
say "-1". This will be in the outer-most register window.
The idea is that we're trying to see if the outer-most register
window gets spilled, and thus the 64-bit values were truncated.
2) Load all the inputs for the montmul/montsqr/mpmul instruction,
down to the inner-most register window.
3) Execute the opcode.
4) Traverse back up to the outer-most register window.
5) Check the sentinel, if it's still "-1" store the results.
Otherwise retry the entire sequence.
This retry is extremely troublesome. If you're just unlucky and an
interrupt or other trap happens, it'll push that outer-most window to
the stack and clear the sentinel when we restore it.
We could retry forever and never make forward progress if interrupts
arrive at a fast enough rate (consider perf events as one example).
So we have do limited retries and fallback to software which is
extremely non-deterministic.
Luckily it's very straightforward to provide a mechanism to let
32-bit applications use a 64-bit stack. Stacks in 64-bit mode are
biased by 2047 bytes, which means that the lowest bit is set in the
actual %sp register value.
So if we see bit zero set in a 32-bit application's stack we treat
it like a 64-bit stack.
Runtime detection of such a facility is tricky, and cumbersome at
best. For example, just trying to use a biased stack and seeing if it
works is hard to recover from (the signal handler will need to use an
alt stack, plus something along the lines of longjmp). Therefore, we
add a system call to report a bitmask of arch specific features like
this in a cheap and less hairy way.
With help from Andy Polyakov.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-27 06:18:37 +08:00
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#define thread32_stack_is_64bit(__SP) (((__SP) & 0x1) != 0)
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#define test_thread_64bit_stack(__SP) \
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((test_thread_flag(TIF_32BIT) && !thread32_stack_is_64bit(__SP)) ? \
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false : true)
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2008-07-18 12:55:51 +08:00
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#endif /* !__ASSEMBLY__ */
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#endif /* __KERNEL__ */
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#endif /* _ASM_THREAD_INFO_H */
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