linux/arch/m68k/mm/memory.c
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

298 lines
7.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/m68k/mm/memory.c
*
* Copyright (C) 1995 Hamish Macdonald
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/gfp.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/traps.h>
#include <asm/machdep.h>
/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
struct page instead of separately kmalloced struct. Stolen from
arch/sparc/mm/srmmu.c ... */
typedef struct list_head ptable_desc;
static LIST_HEAD(ptable_list);
#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
#define PD_MARKBITS(dp) (*(unsigned char *)&PD_PAGE(dp)->index)
#define PTABLE_SIZE (PTRS_PER_PMD * sizeof(pmd_t))
void __init init_pointer_table(unsigned long ptable)
{
ptable_desc *dp;
unsigned long page = ptable & PAGE_MASK;
unsigned char mask = 1 << ((ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (!(PD_MARKBITS(dp) & mask)) {
PD_MARKBITS(dp) = 0xff;
list_add(dp, &ptable_list);
}
PD_MARKBITS(dp) &= ~mask;
pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
/* unreserve the page so it's possible to free that page */
PD_PAGE(dp)->flags &= ~(1 << PG_reserved);
init_page_count(PD_PAGE(dp));
return;
}
pmd_t *get_pointer_table (void)
{
ptable_desc *dp = ptable_list.next;
unsigned char mask = PD_MARKBITS (dp);
unsigned char tmp;
unsigned int off;
/*
* For a pointer table for a user process address space, a
* table is taken from a page allocated for the purpose. Each
* page can hold 8 pointer tables. The page is remapped in
* virtual address space to be noncacheable.
*/
if (mask == 0) {
void *page;
ptable_desc *new;
if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
return NULL;
flush_tlb_kernel_page(page);
nocache_page(page);
new = PD_PTABLE(page);
PD_MARKBITS(new) = 0xfe;
list_add_tail(new, dp);
return (pmd_t *)page;
}
for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += PTABLE_SIZE)
;
PD_MARKBITS(dp) = mask & ~tmp;
if (!PD_MARKBITS(dp)) {
/* move to end of list */
list_move_tail(dp, &ptable_list);
}
return (pmd_t *) (page_address(PD_PAGE(dp)) + off);
}
int free_pointer_table (pmd_t *ptable)
{
ptable_desc *dp;
unsigned long page = (unsigned long)ptable & PAGE_MASK;
unsigned char mask = 1 << (((unsigned long)ptable - page)/PTABLE_SIZE);
dp = PD_PTABLE(page);
if (PD_MARKBITS (dp) & mask)
panic ("table already free!");
PD_MARKBITS (dp) |= mask;
if (PD_MARKBITS(dp) == 0xff) {
/* all tables in page are free, free page */
list_del(dp);
cache_page((void *)page);
free_page (page);
return 1;
} else if (ptable_list.next != dp) {
/*
* move this descriptor to the front of the list, since
* it has one or more free tables.
*/
list_move(dp, &ptable_list);
}
return 0;
}
/* invalidate page in both caches */
static inline void clear040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cinvp %%bc,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* invalidate page in i-cache */
static inline void cleari040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cinvp %%ic,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* push page in both caches */
/* RZ: cpush %bc DOES invalidate %ic, regardless of DPI */
static inline void push040(unsigned long paddr)
{
asm volatile (
"nop\n\t"
".chip 68040\n\t"
"cpushp %%bc,(%0)\n\t"
".chip 68k"
: : "a" (paddr));
}
/* push and invalidate page in both caches, must disable ints
* to avoid invalidating valid data */
static inline void pushcl040(unsigned long paddr)
{
unsigned long flags;
local_irq_save(flags);
push040(paddr);
if (CPU_IS_060)
clear040(paddr);
local_irq_restore(flags);
}
/*
* 040: Hit every page containing an address in the range paddr..paddr+len-1.
* (Low order bits of the ea of a CINVP/CPUSHP are "don't care"s).
* Hit every page until there is a page or less to go. Hit the next page,
* and the one after that if the range hits it.
*/
/* ++roman: A little bit more care is required here: The CINVP instruction
* invalidates cache entries WITHOUT WRITING DIRTY DATA BACK! So the beginning
* and the end of the region must be treated differently if they are not
* exactly at the beginning or end of a page boundary. Else, maybe too much
* data becomes invalidated and thus lost forever. CPUSHP does what we need:
* it invalidates the page after pushing dirty data to memory. (Thanks to Jes
* for discovering the problem!)
*/
/* ... but on the '060, CPUSH doesn't invalidate (for us, since we have set
* the DPI bit in the CACR; would it cause problems with temporarily changing
* this?). So we have to push first and then additionally to invalidate.
*/
/*
* cache_clear() semantics: Clear any cache entries for the area in question,
* without writing back dirty entries first. This is useful if the data will
* be overwritten anyway, e.g. by DMA to memory. The range is defined by a
* _physical_ address.
*/
void cache_clear (unsigned long paddr, int len)
{
if (CPU_IS_COLDFIRE) {
clear_cf_bcache(0, DCACHE_MAX_ADDR);
} else if (CPU_IS_040_OR_060) {
int tmp;
/*
* We need special treatment for the first page, in case it
* is not page-aligned. Page align the addresses to work
* around bug I17 in the 68060.
*/
if ((tmp = -paddr & (PAGE_SIZE - 1))) {
pushcl040(paddr & PAGE_MASK);
if ((len -= tmp) <= 0)
return;
paddr += tmp;
}
tmp = PAGE_SIZE;
paddr &= PAGE_MASK;
while ((len -= tmp) >= 0) {
clear040(paddr);
paddr += tmp;
}
if ((len += tmp))
/* a page boundary gets crossed at the end */
pushcl040(paddr);
}
else /* 68030 or 68020 */
asm volatile ("movec %/cacr,%/d0\n\t"
"oriw %0,%/d0\n\t"
"movec %/d0,%/cacr"
: : "i" (FLUSH_I_AND_D)
: "d0");
#ifdef CONFIG_M68K_L2_CACHE
if(mach_l2_flush)
mach_l2_flush(0);
#endif
}
EXPORT_SYMBOL(cache_clear);
/*
* cache_push() semantics: Write back any dirty cache data in the given area,
* and invalidate the range in the instruction cache. It needs not (but may)
* invalidate those entries also in the data cache. The range is defined by a
* _physical_ address.
*/
void cache_push (unsigned long paddr, int len)
{
if (CPU_IS_COLDFIRE) {
flush_cf_bcache(0, DCACHE_MAX_ADDR);
} else if (CPU_IS_040_OR_060) {
int tmp = PAGE_SIZE;
/*
* on 68040 or 68060, push cache lines for pages in the range;
* on the '040 this also invalidates the pushed lines, but not on
* the '060!
*/
len += paddr & (PAGE_SIZE - 1);
/*
* Work around bug I17 in the 68060 affecting some instruction
* lines not being invalidated properly.
*/
paddr &= PAGE_MASK;
do {
push040(paddr);
paddr += tmp;
} while ((len -= tmp) > 0);
}
/*
* 68030/68020 have no writeback cache. On the other hand,
* cache_push is actually a superset of cache_clear (the lines
* get written back and invalidated), so we should make sure
* to perform the corresponding actions. After all, this is getting
* called in places where we've just loaded code, or whatever, so
* flushing the icache is appropriate; flushing the dcache shouldn't
* be required.
*/
else /* 68030 or 68020 */
asm volatile ("movec %/cacr,%/d0\n\t"
"oriw %0,%/d0\n\t"
"movec %/d0,%/cacr"
: : "i" (FLUSH_I)
: "d0");
#ifdef CONFIG_M68K_L2_CACHE
if(mach_l2_flush)
mach_l2_flush(1);
#endif
}
EXPORT_SYMBOL(cache_push);