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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2012-07-06 20:25:11 +00:00
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#ifndef MM_SLAB_H
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#define MM_SLAB_H
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/*
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* Internal slab definitions
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*/
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2014-10-09 22:26:00 +00:00
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#ifdef CONFIG_SLOB
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/*
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* Common fields provided in kmem_cache by all slab allocators
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* This struct is either used directly by the allocator (SLOB)
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* or the allocator must include definitions for all fields
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* provided in kmem_cache_common in their definition of kmem_cache.
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*
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* Once we can do anonymous structs (C11 standard) we could put a
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* anonymous struct definition in these allocators so that the
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* separate allocations in the kmem_cache structure of SLAB and
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* SLUB is no longer needed.
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*/
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struct kmem_cache {
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unsigned int object_size;/* The original size of the object */
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unsigned int size; /* The aligned/padded/added on size */
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unsigned int align; /* Alignment as calculated */
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags; /* Active flags on the slab */
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2018-04-05 23:21:31 +00:00
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unsigned int useroffset;/* Usercopy region offset */
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unsigned int usersize; /* Usercopy region size */
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2014-10-09 22:26:00 +00:00
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const char *name; /* Slab name for sysfs */
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int refcount; /* Use counter */
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void (*ctor)(void *); /* Called on object slot creation */
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struct list_head list; /* List of all slab caches on the system */
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};
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#endif /* CONFIG_SLOB */
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#ifdef CONFIG_SLAB
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#include <linux/slab_def.h>
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#endif
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#ifdef CONFIG_SLUB
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#include <linux/slub_def.h>
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#endif
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#include <linux/memcontrol.h>
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2016-03-15 21:53:35 +00:00
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#include <linux/fault-inject.h>
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#include <linux/kasan.h>
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#include <linux/kmemleak.h>
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2016-07-26 22:21:56 +00:00
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#include <linux/random.h>
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2017-03-03 09:13:38 +00:00
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#include <linux/sched/mm.h>
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2014-10-09 22:26:00 +00:00
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2012-07-06 20:25:11 +00:00
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/*
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* State of the slab allocator.
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*
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* This is used to describe the states of the allocator during bootup.
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* Allocators use this to gradually bootstrap themselves. Most allocators
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* have the problem that the structures used for managing slab caches are
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* allocated from slab caches themselves.
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*/
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enum slab_state {
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DOWN, /* No slab functionality yet */
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PARTIAL, /* SLUB: kmem_cache_node available */
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2013-01-10 19:14:19 +00:00
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PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
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2012-07-06 20:25:11 +00:00
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UP, /* Slab caches usable but not all extras yet */
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FULL /* Everything is working */
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};
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extern enum slab_state slab_state;
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2012-07-06 20:25:12 +00:00
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/* The slab cache mutex protects the management structures during changes */
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extern struct mutex slab_mutex;
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2012-09-05 00:20:33 +00:00
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/* The list of all slab caches on the system */
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2012-07-06 20:25:12 +00:00
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extern struct list_head slab_caches;
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2012-09-05 00:20:33 +00:00
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/* The slab cache that manages slab cache information */
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extern struct kmem_cache *kmem_cache;
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2017-02-22 23:41:05 +00:00
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/* A table of kmalloc cache names and sizes */
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extern const struct kmalloc_info_struct {
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const char *name;
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2018-04-05 23:20:29 +00:00
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unsigned int size;
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2017-02-22 23:41:05 +00:00
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} kmalloc_info[];
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2013-01-10 19:12:17 +00:00
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#ifndef CONFIG_SLOB
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/* Kmalloc array related functions */
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2015-06-24 23:55:57 +00:00
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void setup_kmalloc_cache_index_table(void);
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2017-11-16 01:32:18 +00:00
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void create_kmalloc_caches(slab_flags_t);
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2013-01-10 19:14:19 +00:00
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/* Find the kmalloc slab corresponding for a certain size */
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struct kmem_cache *kmalloc_slab(size_t, gfp_t);
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2013-01-10 19:12:17 +00:00
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#endif
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2012-09-05 00:20:33 +00:00
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/* Functions provided by the slab allocators */
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2017-11-16 01:32:18 +00:00
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int __kmem_cache_create(struct kmem_cache *, slab_flags_t flags);
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2012-07-06 20:25:11 +00:00
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2018-04-05 23:20:29 +00:00
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struct kmem_cache *create_kmalloc_cache(const char *name, unsigned int size,
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slab_flags_t flags, unsigned int useroffset,
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unsigned int usersize);
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2012-11-28 16:23:07 +00:00
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extern void create_boot_cache(struct kmem_cache *, const char *name,
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2018-04-05 23:20:33 +00:00
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unsigned int size, slab_flags_t flags,
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unsigned int useroffset, unsigned int usersize);
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2012-11-28 16:23:07 +00:00
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2014-10-09 22:26:22 +00:00
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int slab_unmergeable(struct kmem_cache *s);
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2018-04-05 23:20:37 +00:00
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struct kmem_cache *find_mergeable(unsigned size, unsigned align,
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags, const char *name, void (*ctor)(void *));
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2014-10-09 22:26:24 +00:00
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#ifndef CONFIG_SLOB
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2012-12-18 22:22:34 +00:00
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struct kmem_cache *
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2018-04-05 23:20:37 +00:00
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__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags, void (*ctor)(void *));
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2014-10-09 22:26:22 +00:00
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2018-04-05 23:21:24 +00:00
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slab_flags_t kmem_cache_flags(unsigned int object_size,
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags, const char *name,
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2014-10-09 22:26:22 +00:00
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void (*ctor)(void *));
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2012-09-05 00:18:32 +00:00
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#else
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2012-12-18 22:22:34 +00:00
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static inline struct kmem_cache *
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2018-04-05 23:20:37 +00:00
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__kmem_cache_alias(const char *name, unsigned int size, unsigned int align,
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags, void (*ctor)(void *))
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2012-09-05 00:18:32 +00:00
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{ return NULL; }
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2014-10-09 22:26:22 +00:00
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2018-04-05 23:21:24 +00:00
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static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
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2017-11-16 01:32:18 +00:00
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slab_flags_t flags, const char *name,
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2014-10-09 22:26:22 +00:00
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void (*ctor)(void *))
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{
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return flags;
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}
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2012-09-05 00:18:32 +00:00
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#endif
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2012-10-17 11:36:51 +00:00
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/* Legal flag mask for kmem_cache_create(), for various configurations */
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mm: add support for kmem caches in DMA32 zone
Patch series "iommu/io-pgtable-arm-v7s: Use DMA32 zone for page tables",
v6.
This is a followup to the discussion in [1], [2].
IOMMUs using ARMv7 short-descriptor format require page tables (level 1
and 2) to be allocated within the first 4GB of RAM, even on 64-bit
systems.
For L1 tables that are bigger than a page, we can just use
__get_free_pages with GFP_DMA32 (on arm64 systems only, arm would still
use GFP_DMA).
For L2 tables that only take 1KB, it would be a waste to allocate a full
page, so we considered 3 approaches:
1. This series, adding support for GFP_DMA32 slab caches.
2. genalloc, which requires pre-allocating the maximum number of L2 page
tables (4096, so 4MB of memory).
3. page_frag, which is not very memory-efficient as it is unable to reuse
freed fragments until the whole page is freed. [3]
This series is the most memory-efficient approach.
stable@ note:
We confirmed that this is a regression, and IOMMU errors happen on 4.19
and linux-next/master on MT8173 (elm, Acer Chromebook R13). The issue
most likely starts from commit ad67f5a6545f ("arm64: replace ZONE_DMA
with ZONE_DMA32"), i.e. 4.15, and presumably breaks a number of Mediatek
platforms (and maybe others?).
[1] https://lists.linuxfoundation.org/pipermail/iommu/2018-November/030876.html
[2] https://lists.linuxfoundation.org/pipermail/iommu/2018-December/031696.html
[3] https://patchwork.codeaurora.org/patch/671639/
This patch (of 3):
IOMMUs using ARMv7 short-descriptor format require page tables to be
allocated within the first 4GB of RAM, even on 64-bit systems. On arm64,
this is done by passing GFP_DMA32 flag to memory allocation functions.
For IOMMU L2 tables that only take 1KB, it would be a waste to allocate
a full page using get_free_pages, so we considered 3 approaches:
1. This patch, adding support for GFP_DMA32 slab caches.
2. genalloc, which requires pre-allocating the maximum number of L2
page tables (4096, so 4MB of memory).
3. page_frag, which is not very memory-efficient as it is unable
to reuse freed fragments until the whole page is freed.
This change makes it possible to create a custom cache in DMA32 zone using
kmem_cache_create, then allocate memory using kmem_cache_alloc.
We do not create a DMA32 kmalloc cache array, as there are currently no
users of kmalloc(..., GFP_DMA32). These calls will continue to trigger a
warning, as we keep GFP_DMA32 in GFP_SLAB_BUG_MASK.
This implies that calls to kmem_cache_*alloc on a SLAB_CACHE_DMA32
kmem_cache must _not_ use GFP_DMA32 (it is anyway redundant and
unnecessary).
Link: http://lkml.kernel.org/r/20181210011504.122604-2-drinkcat@chromium.org
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Sasha Levin <Alexander.Levin@microsoft.com>
Cc: Huaisheng Ye <yehs1@lenovo.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Yong Wu <yong.wu@mediatek.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Tomasz Figa <tfiga@google.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-29 03:43:42 +00:00
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#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | \
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SLAB_CACHE_DMA32 | SLAB_PANIC | \
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2017-01-18 10:53:44 +00:00
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SLAB_TYPESAFE_BY_RCU | SLAB_DEBUG_OBJECTS )
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2012-10-17 11:36:51 +00:00
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#if defined(CONFIG_DEBUG_SLAB)
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#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
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#elif defined(CONFIG_SLUB_DEBUG)
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#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
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2016-03-15 21:55:06 +00:00
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SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
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2012-10-17 11:36:51 +00:00
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#else
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#define SLAB_DEBUG_FLAGS (0)
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#endif
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#if defined(CONFIG_SLAB)
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#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
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2016-01-14 23:18:15 +00:00
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SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
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2017-11-16 01:35:54 +00:00
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SLAB_ACCOUNT)
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2012-10-17 11:36:51 +00:00
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#elif defined(CONFIG_SLUB)
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#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
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2017-11-16 01:35:54 +00:00
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SLAB_TEMPORARY | SLAB_ACCOUNT)
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2012-10-17 11:36:51 +00:00
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#else
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#define SLAB_CACHE_FLAGS (0)
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#endif
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2016-12-13 00:41:38 +00:00
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/* Common flags available with current configuration */
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2012-10-17 11:36:51 +00:00
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#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
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2016-12-13 00:41:38 +00:00
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/* Common flags permitted for kmem_cache_create */
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#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
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SLAB_RED_ZONE | \
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SLAB_POISON | \
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SLAB_STORE_USER | \
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SLAB_TRACE | \
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SLAB_CONSISTENCY_CHECKS | \
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SLAB_MEM_SPREAD | \
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SLAB_NOLEAKTRACE | \
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SLAB_RECLAIM_ACCOUNT | \
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SLAB_TEMPORARY | \
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SLAB_ACCOUNT)
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2018-04-05 23:21:57 +00:00
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bool __kmem_cache_empty(struct kmem_cache *);
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2012-09-04 23:18:33 +00:00
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int __kmem_cache_shutdown(struct kmem_cache *);
|
2016-02-17 21:11:37 +00:00
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void __kmem_cache_release(struct kmem_cache *);
|
2017-02-22 23:41:27 +00:00
|
|
|
int __kmem_cache_shrink(struct kmem_cache *);
|
|
|
|
void __kmemcg_cache_deactivate(struct kmem_cache *s);
|
2014-05-06 19:50:08 +00:00
|
|
|
void slab_kmem_cache_release(struct kmem_cache *);
|
2012-09-04 23:18:33 +00:00
|
|
|
|
2012-10-19 14:20:25 +00:00
|
|
|
struct seq_file;
|
|
|
|
struct file;
|
|
|
|
|
2012-10-19 14:20:27 +00:00
|
|
|
struct slabinfo {
|
|
|
|
unsigned long active_objs;
|
|
|
|
unsigned long num_objs;
|
|
|
|
unsigned long active_slabs;
|
|
|
|
unsigned long num_slabs;
|
|
|
|
unsigned long shared_avail;
|
|
|
|
unsigned int limit;
|
|
|
|
unsigned int batchcount;
|
|
|
|
unsigned int shared;
|
|
|
|
unsigned int objects_per_slab;
|
|
|
|
unsigned int cache_order;
|
|
|
|
};
|
|
|
|
|
|
|
|
void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
|
|
|
|
void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
|
2012-10-19 14:20:25 +00:00
|
|
|
ssize_t slabinfo_write(struct file *file, const char __user *buffer,
|
|
|
|
size_t count, loff_t *ppos);
|
2012-12-18 22:22:27 +00:00
|
|
|
|
2015-09-04 22:45:34 +00:00
|
|
|
/*
|
|
|
|
* Generic implementation of bulk operations
|
|
|
|
* These are useful for situations in which the allocator cannot
|
2016-03-15 21:54:03 +00:00
|
|
|
* perform optimizations. In that case segments of the object listed
|
2015-09-04 22:45:34 +00:00
|
|
|
* may be allocated or freed using these operations.
|
|
|
|
*/
|
|
|
|
void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
|
2015-11-20 23:57:58 +00:00
|
|
|
int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
|
2015-09-04 22:45:34 +00:00
|
|
|
|
2018-08-17 22:47:25 +00:00
|
|
|
#ifdef CONFIG_MEMCG_KMEM
|
2017-02-22 23:41:24 +00:00
|
|
|
|
|
|
|
/* List of all root caches. */
|
|
|
|
extern struct list_head slab_root_caches;
|
|
|
|
#define root_caches_node memcg_params.__root_caches_node
|
|
|
|
|
2015-02-12 22:59:23 +00:00
|
|
|
/*
|
|
|
|
* Iterate over all memcg caches of the given root cache. The caller must hold
|
|
|
|
* slab_mutex.
|
|
|
|
*/
|
|
|
|
#define for_each_memcg_cache(iter, root) \
|
2017-02-22 23:41:17 +00:00
|
|
|
list_for_each_entry(iter, &(root)->memcg_params.children, \
|
|
|
|
memcg_params.children_node)
|
2015-02-12 22:59:23 +00:00
|
|
|
|
2012-12-18 22:22:27 +00:00
|
|
|
static inline bool is_root_cache(struct kmem_cache *s)
|
|
|
|
{
|
2017-02-22 23:41:17 +00:00
|
|
|
return !s->memcg_params.root_cache;
|
2012-12-18 22:22:27 +00:00
|
|
|
}
|
2012-12-18 22:22:34 +00:00
|
|
|
|
2012-12-18 22:22:46 +00:00
|
|
|
static inline bool slab_equal_or_root(struct kmem_cache *s,
|
2015-02-12 22:59:20 +00:00
|
|
|
struct kmem_cache *p)
|
2012-12-18 22:22:46 +00:00
|
|
|
{
|
2015-02-12 22:59:20 +00:00
|
|
|
return p == s || p == s->memcg_params.root_cache;
|
2012-12-18 22:22:46 +00:00
|
|
|
}
|
2012-12-18 22:23:01 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* We use suffixes to the name in memcg because we can't have caches
|
|
|
|
* created in the system with the same name. But when we print them
|
|
|
|
* locally, better refer to them with the base name
|
|
|
|
*/
|
|
|
|
static inline const char *cache_name(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
if (!is_root_cache(s))
|
2015-02-12 22:59:20 +00:00
|
|
|
s = s->memcg_params.root_cache;
|
2012-12-18 22:23:01 +00:00
|
|
|
return s->name;
|
|
|
|
}
|
|
|
|
|
2014-01-23 23:53:06 +00:00
|
|
|
/*
|
|
|
|
* Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
|
2015-02-12 22:59:20 +00:00
|
|
|
* That said the caller must assure the memcg's cache won't go away by either
|
|
|
|
* taking a css reference to the owner cgroup, or holding the slab_mutex.
|
2014-01-23 23:53:06 +00:00
|
|
|
*/
|
2013-11-12 23:08:23 +00:00
|
|
|
static inline struct kmem_cache *
|
|
|
|
cache_from_memcg_idx(struct kmem_cache *s, int idx)
|
2012-12-18 22:23:01 +00:00
|
|
|
{
|
2014-01-23 23:52:59 +00:00
|
|
|
struct kmem_cache *cachep;
|
2015-02-12 22:59:20 +00:00
|
|
|
struct memcg_cache_array *arr;
|
2014-01-23 23:53:06 +00:00
|
|
|
|
|
|
|
rcu_read_lock();
|
2015-02-12 22:59:20 +00:00
|
|
|
arr = rcu_dereference(s->memcg_params.memcg_caches);
|
2014-01-23 23:52:59 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Make sure we will access the up-to-date value. The code updating
|
|
|
|
* memcg_caches issues a write barrier to match this (see
|
2015-02-12 22:59:20 +00:00
|
|
|
* memcg_create_kmem_cache()).
|
2014-01-23 23:52:59 +00:00
|
|
|
*/
|
2017-10-24 10:22:48 +00:00
|
|
|
cachep = READ_ONCE(arr->entries[idx]);
|
2014-12-10 23:42:28 +00:00
|
|
|
rcu_read_unlock();
|
|
|
|
|
2014-01-23 23:52:59 +00:00
|
|
|
return cachep;
|
2012-12-18 22:23:01 +00:00
|
|
|
}
|
2012-12-18 22:23:03 +00:00
|
|
|
|
|
|
|
static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
if (is_root_cache(s))
|
|
|
|
return s;
|
2015-02-12 22:59:20 +00:00
|
|
|
return s->memcg_params.root_cache;
|
2012-12-18 22:23:03 +00:00
|
|
|
}
|
2014-06-04 23:06:38 +00:00
|
|
|
|
memcg: unify slab and other kmem pages charging
We have memcg_kmem_charge and memcg_kmem_uncharge methods for charging and
uncharging kmem pages to memcg, but currently they are not used for
charging slab pages (i.e. they are only used for charging pages allocated
with alloc_kmem_pages). The only reason why the slab subsystem uses
special helpers, memcg_charge_slab and memcg_uncharge_slab, is that it
needs to charge to the memcg of kmem cache while memcg_charge_kmem charges
to the memcg that the current task belongs to.
To remove this diversity, this patch adds an extra argument to
__memcg_kmem_charge that can be a pointer to a memcg or NULL. If it is
not NULL, the function tries to charge to the memcg it points to,
otherwise it charge to the current context. Next, it makes the slab
subsystem use this function to charge slab pages.
Since memcg_charge_kmem and memcg_uncharge_kmem helpers are now used only
in __memcg_kmem_charge and __memcg_kmem_uncharge, they are inlined. Since
__memcg_kmem_charge stores a pointer to the memcg in the page struct, we
don't need memcg_uncharge_slab anymore and can use free_kmem_pages.
Besides, one can now detect which memcg a slab page belongs to by reading
/proc/kpagecgroup.
Note, this patch switches slab to charge-after-alloc design. Since this
design is already used for all other memcg charges, it should not make any
difference.
[hannes@cmpxchg.org: better to have an outer function than a magic parameter for the memcg lookup]
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 02:49:01 +00:00
|
|
|
static __always_inline int memcg_charge_slab(struct page *page,
|
|
|
|
gfp_t gfp, int order,
|
|
|
|
struct kmem_cache *s)
|
2014-06-04 23:06:38 +00:00
|
|
|
{
|
|
|
|
if (is_root_cache(s))
|
|
|
|
return 0;
|
2017-07-06 22:40:55 +00:00
|
|
|
return memcg_kmem_charge_memcg(page, gfp, order, s->memcg_params.memcg);
|
2016-03-17 21:17:35 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static __always_inline void memcg_uncharge_slab(struct page *page, int order,
|
|
|
|
struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
memcg_kmem_uncharge(page, order);
|
2014-06-04 23:06:38 +00:00
|
|
|
}
|
2015-02-12 22:59:20 +00:00
|
|
|
|
|
|
|
extern void slab_init_memcg_params(struct kmem_cache *);
|
2017-02-22 23:41:24 +00:00
|
|
|
extern void memcg_link_cache(struct kmem_cache *s);
|
2017-02-22 23:41:30 +00:00
|
|
|
extern void slab_deactivate_memcg_cache_rcu_sched(struct kmem_cache *s,
|
|
|
|
void (*deact_fn)(struct kmem_cache *));
|
2015-02-12 22:59:20 +00:00
|
|
|
|
2018-08-17 22:47:25 +00:00
|
|
|
#else /* CONFIG_MEMCG_KMEM */
|
2015-02-12 22:59:20 +00:00
|
|
|
|
2017-02-22 23:41:24 +00:00
|
|
|
/* If !memcg, all caches are root. */
|
|
|
|
#define slab_root_caches slab_caches
|
|
|
|
#define root_caches_node list
|
|
|
|
|
2015-02-12 22:59:23 +00:00
|
|
|
#define for_each_memcg_cache(iter, root) \
|
|
|
|
for ((void)(iter), (void)(root); 0; )
|
|
|
|
|
2012-12-18 22:22:27 +00:00
|
|
|
static inline bool is_root_cache(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
return true;
|
|
|
|
}
|
|
|
|
|
2012-12-18 22:22:46 +00:00
|
|
|
static inline bool slab_equal_or_root(struct kmem_cache *s,
|
|
|
|
struct kmem_cache *p)
|
|
|
|
{
|
2019-07-12 03:53:23 +00:00
|
|
|
return s == p;
|
2012-12-18 22:22:46 +00:00
|
|
|
}
|
2012-12-18 22:23:01 +00:00
|
|
|
|
|
|
|
static inline const char *cache_name(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
return s->name;
|
|
|
|
}
|
|
|
|
|
2013-11-12 23:08:23 +00:00
|
|
|
static inline struct kmem_cache *
|
|
|
|
cache_from_memcg_idx(struct kmem_cache *s, int idx)
|
2012-12-18 22:23:01 +00:00
|
|
|
{
|
|
|
|
return NULL;
|
|
|
|
}
|
2012-12-18 22:23:03 +00:00
|
|
|
|
|
|
|
static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
return s;
|
|
|
|
}
|
2014-06-04 23:06:38 +00:00
|
|
|
|
memcg: unify slab and other kmem pages charging
We have memcg_kmem_charge and memcg_kmem_uncharge methods for charging and
uncharging kmem pages to memcg, but currently they are not used for
charging slab pages (i.e. they are only used for charging pages allocated
with alloc_kmem_pages). The only reason why the slab subsystem uses
special helpers, memcg_charge_slab and memcg_uncharge_slab, is that it
needs to charge to the memcg of kmem cache while memcg_charge_kmem charges
to the memcg that the current task belongs to.
To remove this diversity, this patch adds an extra argument to
__memcg_kmem_charge that can be a pointer to a memcg or NULL. If it is
not NULL, the function tries to charge to the memcg it points to,
otherwise it charge to the current context. Next, it makes the slab
subsystem use this function to charge slab pages.
Since memcg_charge_kmem and memcg_uncharge_kmem helpers are now used only
in __memcg_kmem_charge and __memcg_kmem_uncharge, they are inlined. Since
__memcg_kmem_charge stores a pointer to the memcg in the page struct, we
don't need memcg_uncharge_slab anymore and can use free_kmem_pages.
Besides, one can now detect which memcg a slab page belongs to by reading
/proc/kpagecgroup.
Note, this patch switches slab to charge-after-alloc design. Since this
design is already used for all other memcg charges, it should not make any
difference.
[hannes@cmpxchg.org: better to have an outer function than a magic parameter for the memcg lookup]
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 02:49:01 +00:00
|
|
|
static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
|
|
|
|
struct kmem_cache *s)
|
2014-06-04 23:06:38 +00:00
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2016-03-17 21:17:35 +00:00
|
|
|
static inline void memcg_uncharge_slab(struct page *page, int order,
|
|
|
|
struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
2015-02-12 22:59:20 +00:00
|
|
|
static inline void slab_init_memcg_params(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
}
|
2017-02-22 23:41:24 +00:00
|
|
|
|
|
|
|
static inline void memcg_link_cache(struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
2018-08-17 22:47:25 +00:00
|
|
|
#endif /* CONFIG_MEMCG_KMEM */
|
2012-12-18 22:22:46 +00:00
|
|
|
|
2019-07-12 03:53:26 +00:00
|
|
|
static inline struct kmem_cache *virt_to_cache(const void *obj)
|
|
|
|
{
|
|
|
|
struct page *page;
|
|
|
|
|
|
|
|
page = virt_to_head_page(obj);
|
|
|
|
if (WARN_ONCE(!PageSlab(page), "%s: Object is not a Slab page!\n",
|
|
|
|
__func__))
|
|
|
|
return NULL;
|
|
|
|
return page->slab_cache;
|
|
|
|
}
|
|
|
|
|
2012-12-18 22:22:46 +00:00
|
|
|
static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
|
|
|
|
{
|
|
|
|
struct kmem_cache *cachep;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* When kmemcg is not being used, both assignments should return the
|
|
|
|
* same value. but we don't want to pay the assignment price in that
|
|
|
|
* case. If it is not compiled in, the compiler should be smart enough
|
|
|
|
* to not do even the assignment. In that case, slab_equal_or_root
|
|
|
|
* will also be a constant.
|
|
|
|
*/
|
2016-03-15 21:55:06 +00:00
|
|
|
if (!memcg_kmem_enabled() &&
|
2019-07-12 03:53:23 +00:00
|
|
|
!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) &&
|
2016-03-15 21:55:06 +00:00
|
|
|
!unlikely(s->flags & SLAB_CONSISTENCY_CHECKS))
|
2012-12-18 22:22:46 +00:00
|
|
|
return s;
|
|
|
|
|
2019-07-12 03:53:26 +00:00
|
|
|
cachep = virt_to_cache(x);
|
|
|
|
WARN_ONCE(cachep && !slab_equal_or_root(cachep, s),
|
2019-07-12 03:53:23 +00:00
|
|
|
"%s: Wrong slab cache. %s but object is from %s\n",
|
|
|
|
__func__, s->name, cachep->name);
|
|
|
|
return cachep;
|
2012-12-18 22:22:46 +00:00
|
|
|
}
|
2013-01-10 19:14:19 +00:00
|
|
|
|
2016-03-15 21:53:35 +00:00
|
|
|
static inline size_t slab_ksize(const struct kmem_cache *s)
|
|
|
|
{
|
|
|
|
#ifndef CONFIG_SLUB
|
|
|
|
return s->object_size;
|
|
|
|
|
|
|
|
#else /* CONFIG_SLUB */
|
|
|
|
# ifdef CONFIG_SLUB_DEBUG
|
|
|
|
/*
|
|
|
|
* Debugging requires use of the padding between object
|
|
|
|
* and whatever may come after it.
|
|
|
|
*/
|
|
|
|
if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
|
|
|
|
return s->object_size;
|
|
|
|
# endif
|
2016-07-28 22:49:07 +00:00
|
|
|
if (s->flags & SLAB_KASAN)
|
|
|
|
return s->object_size;
|
2016-03-15 21:53:35 +00:00
|
|
|
/*
|
|
|
|
* If we have the need to store the freelist pointer
|
|
|
|
* back there or track user information then we can
|
|
|
|
* only use the space before that information.
|
|
|
|
*/
|
2017-01-18 10:53:44 +00:00
|
|
|
if (s->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_STORE_USER))
|
2016-03-15 21:53:35 +00:00
|
|
|
return s->inuse;
|
|
|
|
/*
|
|
|
|
* Else we can use all the padding etc for the allocation
|
|
|
|
*/
|
|
|
|
return s->size;
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
|
|
|
|
gfp_t flags)
|
|
|
|
{
|
|
|
|
flags &= gfp_allowed_mask;
|
2017-03-03 09:13:38 +00:00
|
|
|
|
|
|
|
fs_reclaim_acquire(flags);
|
|
|
|
fs_reclaim_release(flags);
|
|
|
|
|
2016-03-15 21:53:35 +00:00
|
|
|
might_sleep_if(gfpflags_allow_blocking(flags));
|
|
|
|
|
2016-03-15 21:53:38 +00:00
|
|
|
if (should_failslab(s, flags))
|
2016-03-15 21:53:35 +00:00
|
|
|
return NULL;
|
|
|
|
|
2016-07-26 22:24:21 +00:00
|
|
|
if (memcg_kmem_enabled() &&
|
|
|
|
((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
|
|
|
|
return memcg_kmem_get_cache(s);
|
|
|
|
|
|
|
|
return s;
|
2016-03-15 21:53:35 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
|
|
|
|
size_t size, void **p)
|
|
|
|
{
|
|
|
|
size_t i;
|
|
|
|
|
|
|
|
flags &= gfp_allowed_mask;
|
|
|
|
for (i = 0; i < size; i++) {
|
2019-02-21 06:19:11 +00:00
|
|
|
p[i] = kasan_slab_alloc(s, p[i], flags);
|
2019-02-21 06:19:16 +00:00
|
|
|
/* As p[i] might get tagged, call kmemleak hook after KASAN. */
|
2019-02-21 06:19:11 +00:00
|
|
|
kmemleak_alloc_recursive(p[i], s->object_size, 1,
|
2016-03-15 21:53:35 +00:00
|
|
|
s->flags, flags);
|
|
|
|
}
|
2016-07-26 22:24:21 +00:00
|
|
|
|
|
|
|
if (memcg_kmem_enabled())
|
|
|
|
memcg_kmem_put_cache(s);
|
2016-03-15 21:53:35 +00:00
|
|
|
}
|
|
|
|
|
2014-08-06 23:04:07 +00:00
|
|
|
#ifndef CONFIG_SLOB
|
2013-01-10 19:14:19 +00:00
|
|
|
/*
|
|
|
|
* The slab lists for all objects.
|
|
|
|
*/
|
|
|
|
struct kmem_cache_node {
|
|
|
|
spinlock_t list_lock;
|
|
|
|
|
|
|
|
#ifdef CONFIG_SLAB
|
|
|
|
struct list_head slabs_partial; /* partial list first, better asm code */
|
|
|
|
struct list_head slabs_full;
|
|
|
|
struct list_head slabs_free;
|
2016-12-13 00:41:44 +00:00
|
|
|
unsigned long total_slabs; /* length of all slab lists */
|
|
|
|
unsigned long free_slabs; /* length of free slab list only */
|
2013-01-10 19:14:19 +00:00
|
|
|
unsigned long free_objects;
|
|
|
|
unsigned int free_limit;
|
|
|
|
unsigned int colour_next; /* Per-node cache coloring */
|
|
|
|
struct array_cache *shared; /* shared per node */
|
2014-08-06 23:04:29 +00:00
|
|
|
struct alien_cache **alien; /* on other nodes */
|
2013-01-10 19:14:19 +00:00
|
|
|
unsigned long next_reap; /* updated without locking */
|
|
|
|
int free_touched; /* updated without locking */
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef CONFIG_SLUB
|
|
|
|
unsigned long nr_partial;
|
|
|
|
struct list_head partial;
|
|
|
|
#ifdef CONFIG_SLUB_DEBUG
|
|
|
|
atomic_long_t nr_slabs;
|
|
|
|
atomic_long_t total_objects;
|
|
|
|
struct list_head full;
|
|
|
|
#endif
|
|
|
|
#endif
|
|
|
|
|
|
|
|
};
|
2013-07-04 00:33:23 +00:00
|
|
|
|
2014-08-06 23:04:07 +00:00
|
|
|
static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
|
|
|
|
{
|
|
|
|
return s->node[node];
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Iterator over all nodes. The body will be executed for each node that has
|
|
|
|
* a kmem_cache_node structure allocated (which is true for all online nodes)
|
|
|
|
*/
|
|
|
|
#define for_each_kmem_cache_node(__s, __node, __n) \
|
2014-10-09 22:26:20 +00:00
|
|
|
for (__node = 0; __node < nr_node_ids; __node++) \
|
|
|
|
if ((__n = get_node(__s, __node)))
|
2014-08-06 23:04:07 +00:00
|
|
|
|
|
|
|
#endif
|
|
|
|
|
2014-12-10 23:42:16 +00:00
|
|
|
void *slab_start(struct seq_file *m, loff_t *pos);
|
2013-07-08 00:08:28 +00:00
|
|
|
void *slab_next(struct seq_file *m, void *p, loff_t *pos);
|
|
|
|
void slab_stop(struct seq_file *m, void *p);
|
2017-02-22 23:41:21 +00:00
|
|
|
void *memcg_slab_start(struct seq_file *m, loff_t *pos);
|
|
|
|
void *memcg_slab_next(struct seq_file *m, void *p, loff_t *pos);
|
|
|
|
void memcg_slab_stop(struct seq_file *m, void *p);
|
2014-12-10 23:44:19 +00:00
|
|
|
int memcg_slab_show(struct seq_file *m, void *p);
|
2014-08-06 23:04:14 +00:00
|
|
|
|
2017-11-16 01:32:07 +00:00
|
|
|
#if defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)
|
|
|
|
void dump_unreclaimable_slab(void);
|
|
|
|
#else
|
|
|
|
static inline void dump_unreclaimable_slab(void)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
mm: kasan: initial memory quarantine implementation
Quarantine isolates freed objects in a separate queue. The objects are
returned to the allocator later, which helps to detect use-after-free
errors.
When the object is freed, its state changes from KASAN_STATE_ALLOC to
KASAN_STATE_QUARANTINE. The object is poisoned and put into quarantine
instead of being returned to the allocator, therefore every subsequent
access to that object triggers a KASAN error, and the error handler is
able to say where the object has been allocated and deallocated.
When it's time for the object to leave quarantine, its state becomes
KASAN_STATE_FREE and it's returned to the allocator. From now on the
allocator may reuse it for another allocation. Before that happens,
it's still possible to detect a use-after free on that object (it
retains the allocation/deallocation stacks).
When the allocator reuses this object, the shadow is unpoisoned and old
allocation/deallocation stacks are wiped. Therefore a use of this
object, even an incorrect one, won't trigger ASan warning.
Without the quarantine, it's not guaranteed that the objects aren't
reused immediately, that's why the probability of catching a
use-after-free is lower than with quarantine in place.
Quarantine isolates freed objects in a separate queue. The objects are
returned to the allocator later, which helps to detect use-after-free
errors.
Freed objects are first added to per-cpu quarantine queues. When a
cache is destroyed or memory shrinking is requested, the objects are
moved into the global quarantine queue. Whenever a kmalloc call allows
memory reclaiming, the oldest objects are popped out of the global queue
until the total size of objects in quarantine is less than 3/4 of the
maximum quarantine size (which is a fraction of installed physical
memory).
As long as an object remains in the quarantine, KASAN is able to report
accesses to it, so the chance of reporting a use-after-free is
increased. Once the object leaves quarantine, the allocator may reuse
it, in which case the object is unpoisoned and KASAN can't detect
incorrect accesses to it.
Right now quarantine support is only enabled in SLAB allocator.
Unification of KASAN features in SLAB and SLUB will be done later.
This patch is based on the "mm: kasan: quarantine" patch originally
prepared by Dmitry Chernenkov. A number of improvements have been
suggested by Andrey Ryabinin.
[glider@google.com: v9]
Link: http://lkml.kernel.org/r/1462987130-144092-1-git-send-email-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 23:59:11 +00:00
|
|
|
void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
|
|
|
|
|
2016-07-26 22:21:56 +00:00
|
|
|
#ifdef CONFIG_SLAB_FREELIST_RANDOM
|
|
|
|
int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
|
|
|
|
gfp_t gfp);
|
|
|
|
void cache_random_seq_destroy(struct kmem_cache *cachep);
|
|
|
|
#else
|
|
|
|
static inline int cache_random_seq_create(struct kmem_cache *cachep,
|
|
|
|
unsigned int count, gfp_t gfp)
|
|
|
|
{
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
|
|
|
|
#endif /* CONFIG_SLAB_FREELIST_RANDOM */
|
|
|
|
|
2014-08-06 23:04:14 +00:00
|
|
|
#endif /* MM_SLAB_H */
|