linux_dsm_epyc7002/arch/sparc/include/asm/mmu_context_64.h
Greg Kroah-Hartman b24413180f 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>
2017-11-02 11:10:55 +01:00

140 lines
4.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __SPARC64_MMU_CONTEXT_H
#define __SPARC64_MMU_CONTEXT_H
/* Derived heavily from Linus's Alpha/AXP ASN code... */
#ifndef __ASSEMBLY__
#include <linux/spinlock.h>
#include <linux/mm_types.h>
#include <asm/spitfire.h>
#include <asm-generic/mm_hooks.h>
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
}
extern spinlock_t ctx_alloc_lock;
extern unsigned long tlb_context_cache;
extern unsigned long mmu_context_bmap[];
DECLARE_PER_CPU(struct mm_struct *, per_cpu_secondary_mm);
void get_new_mmu_context(struct mm_struct *mm);
int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
void destroy_context(struct mm_struct *mm);
void __tsb_context_switch(unsigned long pgd_pa,
struct tsb_config *tsb_base,
struct tsb_config *tsb_huge,
unsigned long tsb_descr_pa,
unsigned long secondary_ctx);
static inline void tsb_context_switch_ctx(struct mm_struct *mm,
unsigned long ctx)
{
__tsb_context_switch(__pa(mm->pgd),
&mm->context.tsb_block[MM_TSB_BASE],
#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
(mm->context.tsb_block[MM_TSB_HUGE].tsb ?
&mm->context.tsb_block[MM_TSB_HUGE] :
NULL)
#else
NULL
#endif
, __pa(&mm->context.tsb_descr[MM_TSB_BASE]),
ctx);
}
#define tsb_context_switch(X) tsb_context_switch_ctx(X, 0)
void tsb_grow(struct mm_struct *mm,
unsigned long tsb_index,
unsigned long mm_rss);
#ifdef CONFIG_SMP
void smp_tsb_sync(struct mm_struct *mm);
#else
#define smp_tsb_sync(__mm) do { } while (0)
#endif
/* Set MMU context in the actual hardware. */
#define load_secondary_context(__mm) \
__asm__ __volatile__( \
"\n661: stxa %0, [%1] %2\n" \
" .section .sun4v_1insn_patch, \"ax\"\n" \
" .word 661b\n" \
" stxa %0, [%1] %3\n" \
" .previous\n" \
" flush %%g6\n" \
: /* No outputs */ \
: "r" (CTX_HWBITS((__mm)->context)), \
"r" (SECONDARY_CONTEXT), "i" (ASI_DMMU), "i" (ASI_MMU))
void __flush_tlb_mm(unsigned long, unsigned long);
/* Switch the current MM context. */
static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
{
unsigned long ctx_valid, flags;
int cpu = smp_processor_id();
per_cpu(per_cpu_secondary_mm, cpu) = mm;
if (unlikely(mm == &init_mm))
return;
spin_lock_irqsave(&mm->context.lock, flags);
ctx_valid = CTX_VALID(mm->context);
if (!ctx_valid)
get_new_mmu_context(mm);
/* We have to be extremely careful here or else we will miss
* a TSB grow if we switch back and forth between a kernel
* thread and an address space which has it's TSB size increased
* on another processor.
*
* It is possible to play some games in order to optimize the
* switch, but the safest thing to do is to unconditionally
* perform the secondary context load and the TSB context switch.
*
* For reference the bad case is, for address space "A":
*
* CPU 0 CPU 1
* run address space A
* set cpu0's bits in cpu_vm_mask
* switch to kernel thread, borrow
* address space A via entry_lazy_tlb
* run address space A
* set cpu1's bit in cpu_vm_mask
* flush_tlb_pending()
* reset cpu_vm_mask to just cpu1
* TSB grow
* run address space A
* context was valid, so skip
* TSB context switch
*
* At that point cpu0 continues to use a stale TSB, the one from
* before the TSB grow performed on cpu1. cpu1 did not cross-call
* cpu0 to update it's TSB because at that point the cpu_vm_mask
* only had cpu1 set in it.
*/
tsb_context_switch_ctx(mm, CTX_HWBITS(mm->context));
/* Any time a processor runs a context on an address space
* for the first time, we must flush that context out of the
* local TLB.
*/
if (!ctx_valid || !cpumask_test_cpu(cpu, mm_cpumask(mm))) {
cpumask_set_cpu(cpu, mm_cpumask(mm));
__flush_tlb_mm(CTX_HWBITS(mm->context),
SECONDARY_CONTEXT);
}
spin_unlock_irqrestore(&mm->context.lock, flags);
}
#define deactivate_mm(tsk,mm) do { } while (0)
#define activate_mm(active_mm, mm) switch_mm(active_mm, mm, NULL)
#endif /* !(__ASSEMBLY__) */
#endif /* !(__SPARC64_MMU_CONTEXT_H) */