License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2006-03-22 08:09:12 +00:00
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#ifndef _LINUX_MIGRATE_H
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#define _LINUX_MIGRATE_H
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#include <linux/mm.h>
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2007-05-06 21:50:20 +00:00
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#include <linux/mempolicy.h>
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2012-01-20 22:33:53 +00:00
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#include <linux/migrate_mode.h>
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2017-07-10 22:48:47 +00:00
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#include <linux/hugetlb.h>
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2006-03-22 08:09:12 +00:00
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2018-04-10 23:30:03 +00:00
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typedef struct page *new_page_t(struct page *page, unsigned long private);
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2014-06-04 23:08:25 +00:00
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typedef void free_page_t(struct page *page, unsigned long private);
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2006-06-23 09:03:53 +00:00
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2012-12-12 00:02:31 +00:00
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/*
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* Return values from addresss_space_operations.migratepage():
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* - negative errno on page migration failure;
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* - zero on page migration success;
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*/
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#define MIGRATEPAGE_SUCCESS 0
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2014-10-09 22:29:27 +00:00
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2012-10-19 13:07:31 +00:00
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enum migrate_reason {
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MR_COMPACTION,
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MR_MEMORY_FAILURE,
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MR_MEMORY_HOTPLUG,
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MR_SYSCALL, /* also applies to cpusets */
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MR_MEMPOLICY_MBIND,
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2012-10-25 12:16:34 +00:00
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MR_NUMA_MISPLACED,
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2018-04-05 23:22:08 +00:00
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MR_CONTIG_RANGE,
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2016-03-15 21:56:18 +00:00
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MR_TYPES
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2012-10-19 13:07:31 +00:00
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};
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2012-12-12 00:02:31 +00:00
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2016-03-15 21:56:18 +00:00
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/* In mm/debug.c; also keep sync with include/trace/events/migrate.h */
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2018-12-28 08:35:59 +00:00
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extern const char *migrate_reason_names[MR_TYPES];
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2016-03-15 21:56:18 +00:00
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2017-07-10 22:48:47 +00:00
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static inline struct page *new_page_nodemask(struct page *page,
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int preferred_nid, nodemask_t *nodemask)
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{
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2017-07-12 21:36:58 +00:00
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gfp_t gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL;
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2017-09-08 23:11:15 +00:00
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unsigned int order = 0;
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struct page *new_page = NULL;
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2017-07-10 22:48:47 +00:00
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if (PageHuge(page))
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return alloc_huge_page_nodemask(page_hstate(compound_head(page)),
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2017-07-10 22:49:11 +00:00
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preferred_nid, nodemask);
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2017-07-10 22:48:47 +00:00
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2018-04-10 23:30:07 +00:00
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if (PageTransHuge(page)) {
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2017-09-08 23:11:15 +00:00
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gfp_mask |= GFP_TRANSHUGE;
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2018-04-10 23:30:07 +00:00
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order = HPAGE_PMD_ORDER;
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2017-09-08 23:11:15 +00:00
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}
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2017-07-10 22:48:47 +00:00
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if (PageHighMem(page) || (zone_idx(page_zone(page)) == ZONE_MOVABLE))
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gfp_mask |= __GFP_HIGHMEM;
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2017-09-08 23:11:15 +00:00
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new_page = __alloc_pages_nodemask(gfp_mask, order,
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preferred_nid, nodemask);
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2017-11-30 00:11:12 +00:00
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if (new_page && PageTransHuge(new_page))
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2017-09-08 23:11:15 +00:00
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prep_transhuge_page(new_page);
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return new_page;
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2017-07-10 22:48:47 +00:00
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}
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|
2007-05-06 21:50:20 +00:00
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#ifdef CONFIG_MIGRATION
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2009-01-06 22:39:16 +00:00
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2012-12-12 00:02:47 +00:00
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extern void putback_movable_pages(struct list_head *l);
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2017-05-03 21:54:45 +00:00
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extern int migrate_page(struct address_space *mapping,
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struct page *newpage, struct page *page,
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enum migrate_mode mode);
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2014-06-04 23:08:25 +00:00
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extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free,
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2013-02-23 00:35:14 +00:00
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unsigned long private, enum migrate_mode mode, int reason);
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2017-02-24 22:57:29 +00:00
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extern int isolate_movable_page(struct page *page, isolate_mode_t mode);
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mm: migrate: support non-lru movable page migration
We have allowed migration for only LRU pages until now and it was enough
to make high-order pages. But recently, embedded system(e.g., webOS,
android) uses lots of non-movable pages(e.g., zram, GPU memory) so we
have seen several reports about troubles of small high-order allocation.
For fixing the problem, there were several efforts (e,g,. enhance
compaction algorithm, SLUB fallback to 0-order page, reserved memory,
vmalloc and so on) but if there are lots of non-movable pages in system,
their solutions are void in the long run.
So, this patch is to support facility to change non-movable pages with
movable. For the feature, this patch introduces functions related to
migration to address_space_operations as well as some page flags.
If a driver want to make own pages movable, it should define three
functions which are function pointers of struct
address_space_operations.
1. bool (*isolate_page) (struct page *page, isolate_mode_t mode);
What VM expects on isolate_page function of driver is to return *true*
if driver isolates page successfully. On returing true, VM marks the
page as PG_isolated so concurrent isolation in several CPUs skip the
page for isolation. If a driver cannot isolate the page, it should
return *false*.
Once page is successfully isolated, VM uses page.lru fields so driver
shouldn't expect to preserve values in that fields.
2. int (*migratepage) (struct address_space *mapping,
struct page *newpage, struct page *oldpage, enum migrate_mode);
After isolation, VM calls migratepage of driver with isolated page. The
function of migratepage is to move content of the old page to new page
and set up fields of struct page newpage. Keep in mind that you should
indicate to the VM the oldpage is no longer movable via
__ClearPageMovable() under page_lock if you migrated the oldpage
successfully and returns 0. If driver cannot migrate the page at the
moment, driver can return -EAGAIN. On -EAGAIN, VM will retry page
migration in a short time because VM interprets -EAGAIN as "temporal
migration failure". On returning any error except -EAGAIN, VM will give
up the page migration without retrying in this time.
Driver shouldn't touch page.lru field VM using in the functions.
3. void (*putback_page)(struct page *);
If migration fails on isolated page, VM should return the isolated page
to the driver so VM calls driver's putback_page with migration failed
page. In this function, driver should put the isolated page back to the
own data structure.
4. non-lru movable page flags
There are two page flags for supporting non-lru movable page.
* PG_movable
Driver should use the below function to make page movable under
page_lock.
void __SetPageMovable(struct page *page, struct address_space *mapping)
It needs argument of address_space for registering migration family
functions which will be called by VM. Exactly speaking, PG_movable is
not a real flag of struct page. Rather than, VM reuses page->mapping's
lower bits to represent it.
#define PAGE_MAPPING_MOVABLE 0x2
page->mapping = page->mapping | PAGE_MAPPING_MOVABLE;
so driver shouldn't access page->mapping directly. Instead, driver
should use page_mapping which mask off the low two bits of page->mapping
so it can get right struct address_space.
For testing of non-lru movable page, VM supports __PageMovable function.
However, it doesn't guarantee to identify non-lru movable page because
page->mapping field is unified with other variables in struct page. As
well, if driver releases the page after isolation by VM, page->mapping
doesn't have stable value although it has PAGE_MAPPING_MOVABLE (Look at
__ClearPageMovable). But __PageMovable is cheap to catch whether page
is LRU or non-lru movable once the page has been isolated. Because LRU
pages never can have PAGE_MAPPING_MOVABLE in page->mapping. It is also
good for just peeking to test non-lru movable pages before more
expensive checking with lock_page in pfn scanning to select victim.
For guaranteeing non-lru movable page, VM provides PageMovable function.
Unlike __PageMovable, PageMovable functions validates page->mapping and
mapping->a_ops->isolate_page under lock_page. The lock_page prevents
sudden destroying of page->mapping.
Driver using __SetPageMovable should clear the flag via
__ClearMovablePage under page_lock before the releasing the page.
* PG_isolated
To prevent concurrent isolation among several CPUs, VM marks isolated
page as PG_isolated under lock_page. So if a CPU encounters PG_isolated
non-lru movable page, it can skip it. Driver doesn't need to manipulate
the flag because VM will set/clear it automatically. Keep in mind that
if driver sees PG_isolated page, it means the page have been isolated by
VM so it shouldn't touch page.lru field. PG_isolated is alias with
PG_reclaim flag so driver shouldn't use the flag for own purpose.
[opensource.ganesh@gmail.com: mm/compaction: remove local variable is_lru]
Link: http://lkml.kernel.org/r/20160618014841.GA7422@leo-test
Link: http://lkml.kernel.org/r/1464736881-24886-3-git-send-email-minchan@kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: John Einar Reitan <john.reitan@foss.arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 22:23:05 +00:00
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extern void putback_movable_page(struct page *page);
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2006-06-23 09:03:53 +00:00
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2006-03-22 08:09:12 +00:00
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extern int migrate_prep(void);
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2010-05-24 21:32:27 +00:00
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extern int migrate_prep_local(void);
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2017-09-08 23:12:06 +00:00
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extern void migrate_page_states(struct page *newpage, struct page *page);
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2010-09-08 01:19:35 +00:00
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extern void migrate_page_copy(struct page *newpage, struct page *page);
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extern int migrate_huge_page_move_mapping(struct address_space *mapping,
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struct page *newpage, struct page *page);
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2013-07-16 09:56:16 +00:00
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extern int migrate_page_move_mapping(struct address_space *mapping,
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2019-07-18 22:58:46 +00:00
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struct page *newpage, struct page *page, int extra_count);
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2006-03-22 08:09:12 +00:00
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#else
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2009-01-06 22:39:16 +00:00
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2012-12-12 00:02:47 +00:00
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static inline void putback_movable_pages(struct list_head *l) {}
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2014-06-04 23:08:25 +00:00
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static inline int migrate_pages(struct list_head *l, new_page_t new,
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free_page_t free, unsigned long private, enum migrate_mode mode,
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int reason)
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2013-02-23 00:35:14 +00:00
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{ return -ENOSYS; }
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2017-02-24 22:57:32 +00:00
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static inline int isolate_movable_page(struct page *page, isolate_mode_t mode)
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{ return -EBUSY; }
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2006-03-31 10:29:56 +00:00
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2006-03-22 08:09:12 +00:00
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static inline int migrate_prep(void) { return -ENOSYS; }
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2010-05-24 21:32:27 +00:00
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static inline int migrate_prep_local(void) { return -ENOSYS; }
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2006-03-22 08:09:12 +00:00
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2017-09-08 23:12:06 +00:00
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static inline void migrate_page_states(struct page *newpage, struct page *page)
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{
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}
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2010-09-08 01:19:35 +00:00
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static inline void migrate_page_copy(struct page *newpage,
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struct page *page) {}
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2010-09-30 02:54:51 +00:00
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static inline int migrate_huge_page_move_mapping(struct address_space *mapping,
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2010-09-08 01:19:35 +00:00
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struct page *newpage, struct page *page)
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{
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return -ENOSYS;
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}
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2006-03-22 08:09:12 +00:00
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#endif /* CONFIG_MIGRATION */
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2012-10-25 12:16:34 +00:00
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2016-07-26 22:26:50 +00:00
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#ifdef CONFIG_COMPACTION
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extern int PageMovable(struct page *page);
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extern void __SetPageMovable(struct page *page, struct address_space *mapping);
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extern void __ClearPageMovable(struct page *page);
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#else
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static inline int PageMovable(struct page *page) { return 0; };
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static inline void __SetPageMovable(struct page *page,
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struct address_space *mapping)
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{
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}
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static inline void __ClearPageMovable(struct page *page)
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{
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}
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#endif
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2012-10-25 12:16:34 +00:00
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#ifdef CONFIG_NUMA_BALANCING
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2013-12-19 01:08:42 +00:00
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extern bool pmd_trans_migrating(pmd_t pmd);
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2013-10-07 10:29:05 +00:00
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extern int migrate_misplaced_page(struct page *page,
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struct vm_area_struct *vma, int node);
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2012-10-25 12:16:34 +00:00
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#else
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2013-12-19 01:08:42 +00:00
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static inline bool pmd_trans_migrating(pmd_t pmd)
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{
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return false;
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}
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2013-10-07 10:29:05 +00:00
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static inline int migrate_misplaced_page(struct page *page,
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struct vm_area_struct *vma, int node)
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2012-10-25 12:16:34 +00:00
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{
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return -EAGAIN; /* can't migrate now */
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}
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2012-12-05 09:32:56 +00:00
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#endif /* CONFIG_NUMA_BALANCING */
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2012-11-19 12:35:47 +00:00
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2012-12-05 09:32:56 +00:00
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#if defined(CONFIG_NUMA_BALANCING) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
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extern int migrate_misplaced_transhuge_page(struct mm_struct *mm,
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struct vm_area_struct *vma,
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pmd_t *pmd, pmd_t entry,
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unsigned long address,
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struct page *page, int node);
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#else
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2012-11-19 12:35:47 +00:00
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static inline int migrate_misplaced_transhuge_page(struct mm_struct *mm,
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struct vm_area_struct *vma,
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pmd_t *pmd, pmd_t entry,
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unsigned long address,
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|
struct page *page, int node)
|
|
|
|
{
|
|
|
|
return -EAGAIN;
|
|
|
|
}
|
2012-12-05 09:32:56 +00:00
|
|
|
#endif /* CONFIG_NUMA_BALANCING && CONFIG_TRANSPARENT_HUGEPAGE*/
|
2012-10-25 12:16:34 +00:00
|
|
|
|
2017-09-08 23:12:09 +00:00
|
|
|
|
|
|
|
#ifdef CONFIG_MIGRATION
|
|
|
|
|
2017-09-08 23:12:17 +00:00
|
|
|
/*
|
|
|
|
* Watch out for PAE architecture, which has an unsigned long, and might not
|
|
|
|
* have enough bits to store all physical address and flags. So far we have
|
|
|
|
* enough room for all our flags.
|
|
|
|
*/
|
2017-09-08 23:12:09 +00:00
|
|
|
#define MIGRATE_PFN_VALID (1UL << 0)
|
|
|
|
#define MIGRATE_PFN_MIGRATE (1UL << 1)
|
|
|
|
#define MIGRATE_PFN_LOCKED (1UL << 2)
|
|
|
|
#define MIGRATE_PFN_WRITE (1UL << 3)
|
2017-09-08 23:12:17 +00:00
|
|
|
#define MIGRATE_PFN_DEVICE (1UL << 4)
|
|
|
|
#define MIGRATE_PFN_ERROR (1UL << 5)
|
|
|
|
#define MIGRATE_PFN_SHIFT 6
|
2017-09-08 23:12:09 +00:00
|
|
|
|
|
|
|
static inline struct page *migrate_pfn_to_page(unsigned long mpfn)
|
|
|
|
{
|
|
|
|
if (!(mpfn & MIGRATE_PFN_VALID))
|
|
|
|
return NULL;
|
|
|
|
return pfn_to_page(mpfn >> MIGRATE_PFN_SHIFT);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline unsigned long migrate_pfn(unsigned long pfn)
|
|
|
|
{
|
|
|
|
return (pfn << MIGRATE_PFN_SHIFT) | MIGRATE_PFN_VALID;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* struct migrate_vma_ops - migrate operation callback
|
|
|
|
*
|
|
|
|
* @alloc_and_copy: alloc destination memory and copy source memory to it
|
|
|
|
* @finalize_and_map: allow caller to map the successfully migrated pages
|
|
|
|
*
|
|
|
|
*
|
|
|
|
* The alloc_and_copy() callback happens once all source pages have been locked,
|
|
|
|
* unmapped and checked (checked whether pinned or not). All pages that can be
|
|
|
|
* migrated will have an entry in the src array set with the pfn value of the
|
|
|
|
* page and with the MIGRATE_PFN_VALID and MIGRATE_PFN_MIGRATE flag set (other
|
|
|
|
* flags might be set but should be ignored by the callback).
|
|
|
|
*
|
|
|
|
* The alloc_and_copy() callback can then allocate destination memory and copy
|
|
|
|
* source memory to it for all those entries (ie with MIGRATE_PFN_VALID and
|
|
|
|
* MIGRATE_PFN_MIGRATE flag set). Once these are allocated and copied, the
|
|
|
|
* callback must update each corresponding entry in the dst array with the pfn
|
|
|
|
* value of the destination page and with the MIGRATE_PFN_VALID and
|
|
|
|
* MIGRATE_PFN_LOCKED flags set (destination pages must have their struct pages
|
|
|
|
* locked, via lock_page()).
|
|
|
|
*
|
|
|
|
* At this point the alloc_and_copy() callback is done and returns.
|
|
|
|
*
|
|
|
|
* Note that the callback does not have to migrate all the pages that are
|
|
|
|
* marked with MIGRATE_PFN_MIGRATE flag in src array unless this is a migration
|
|
|
|
* from device memory to system memory (ie the MIGRATE_PFN_DEVICE flag is also
|
|
|
|
* set in the src array entry). If the device driver cannot migrate a device
|
|
|
|
* page back to system memory, then it must set the corresponding dst array
|
|
|
|
* entry to MIGRATE_PFN_ERROR. This will trigger a SIGBUS if CPU tries to
|
|
|
|
* access any of the virtual addresses originally backed by this page. Because
|
|
|
|
* a SIGBUS is such a severe result for the userspace process, the device
|
|
|
|
* driver should avoid setting MIGRATE_PFN_ERROR unless it is really in an
|
|
|
|
* unrecoverable state.
|
|
|
|
*
|
2017-09-08 23:12:21 +00:00
|
|
|
* For empty entry inside CPU page table (pte_none() or pmd_none() is true) we
|
|
|
|
* do set MIGRATE_PFN_MIGRATE flag inside the corresponding source array thus
|
|
|
|
* allowing device driver to allocate device memory for those unback virtual
|
|
|
|
* address. For this the device driver simply have to allocate device memory
|
|
|
|
* and properly set the destination entry like for regular migration. Note that
|
|
|
|
* this can still fails and thus inside the device driver must check if the
|
|
|
|
* migration was successful for those entry inside the finalize_and_map()
|
|
|
|
* callback just like for regular migration.
|
|
|
|
*
|
2017-09-08 23:12:09 +00:00
|
|
|
* THE alloc_and_copy() CALLBACK MUST NOT CHANGE ANY OF THE SRC ARRAY ENTRIES
|
|
|
|
* OR BAD THINGS WILL HAPPEN !
|
|
|
|
*
|
|
|
|
*
|
|
|
|
* The finalize_and_map() callback happens after struct page migration from
|
|
|
|
* source to destination (destination struct pages are the struct pages for the
|
|
|
|
* memory allocated by the alloc_and_copy() callback). Migration can fail, and
|
|
|
|
* thus the finalize_and_map() allows the driver to inspect which pages were
|
|
|
|
* successfully migrated, and which were not. Successfully migrated pages will
|
|
|
|
* have the MIGRATE_PFN_MIGRATE flag set for their src array entry.
|
|
|
|
*
|
|
|
|
* It is safe to update device page table from within the finalize_and_map()
|
|
|
|
* callback because both destination and source page are still locked, and the
|
|
|
|
* mmap_sem is held in read mode (hence no one can unmap the range being
|
|
|
|
* migrated).
|
|
|
|
*
|
|
|
|
* Once callback is done cleaning up things and updating its page table (if it
|
|
|
|
* chose to do so, this is not an obligation) then it returns. At this point,
|
|
|
|
* the HMM core will finish up the final steps, and the migration is complete.
|
|
|
|
*
|
|
|
|
* THE finalize_and_map() CALLBACK MUST NOT CHANGE ANY OF THE SRC OR DST ARRAY
|
|
|
|
* ENTRIES OR BAD THINGS WILL HAPPEN !
|
|
|
|
*/
|
|
|
|
struct migrate_vma_ops {
|
|
|
|
void (*alloc_and_copy)(struct vm_area_struct *vma,
|
|
|
|
const unsigned long *src,
|
|
|
|
unsigned long *dst,
|
|
|
|
unsigned long start,
|
|
|
|
unsigned long end,
|
|
|
|
void *private);
|
|
|
|
void (*finalize_and_map)(struct vm_area_struct *vma,
|
|
|
|
const unsigned long *src,
|
|
|
|
const unsigned long *dst,
|
|
|
|
unsigned long start,
|
|
|
|
unsigned long end,
|
|
|
|
void *private);
|
|
|
|
};
|
|
|
|
|
2017-09-08 23:12:32 +00:00
|
|
|
#if defined(CONFIG_MIGRATE_VMA_HELPER)
|
2017-09-08 23:12:09 +00:00
|
|
|
int migrate_vma(const struct migrate_vma_ops *ops,
|
|
|
|
struct vm_area_struct *vma,
|
|
|
|
unsigned long start,
|
|
|
|
unsigned long end,
|
|
|
|
unsigned long *src,
|
|
|
|
unsigned long *dst,
|
|
|
|
void *private);
|
2017-09-08 23:12:32 +00:00
|
|
|
#else
|
|
|
|
static inline int migrate_vma(const struct migrate_vma_ops *ops,
|
|
|
|
struct vm_area_struct *vma,
|
|
|
|
unsigned long start,
|
|
|
|
unsigned long end,
|
|
|
|
unsigned long *src,
|
|
|
|
unsigned long *dst,
|
|
|
|
void *private)
|
|
|
|
{
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
#endif /* IS_ENABLED(CONFIG_MIGRATE_VMA_HELPER) */
|
2017-09-08 23:12:09 +00:00
|
|
|
|
|
|
|
#endif /* CONFIG_MIGRATION */
|
|
|
|
|
2006-03-22 08:09:12 +00:00
|
|
|
#endif /* _LINUX_MIGRATE_H */
|