2019-05-20 17:08:00 +00:00
|
|
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
2009-10-06 03:04:15 +00:00
|
|
|
/*
|
|
|
|
* Squashfs - a compressed read only filesystem for Linux
|
|
|
|
*
|
|
|
|
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
|
2011-05-26 09:39:56 +00:00
|
|
|
* Phillip Lougher <phillip@squashfs.org.uk>
|
2009-10-06 03:04:15 +00:00
|
|
|
*
|
|
|
|
* decompressor.c
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/types.h>
|
|
|
|
#include <linux/mutex.h>
|
2011-02-28 01:45:42 +00:00
|
|
|
#include <linux/slab.h>
|
2009-10-06 03:04:15 +00:00
|
|
|
#include <linux/buffer_head.h>
|
|
|
|
|
|
|
|
#include "squashfs_fs.h"
|
|
|
|
#include "squashfs_fs_sb.h"
|
|
|
|
#include "decompressor.h"
|
|
|
|
#include "squashfs.h"
|
2013-11-18 02:59:12 +00:00
|
|
|
#include "page_actor.h"
|
2009-10-06 03:04:15 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* This file (and decompressor.h) implements a decompressor framework for
|
|
|
|
* Squashfs, allowing multiple decompressors to be easily supported
|
|
|
|
*/
|
|
|
|
|
2009-10-14 02:58:11 +00:00
|
|
|
static const struct squashfs_decompressor squashfs_lzma_unsupported_comp_ops = {
|
2013-11-13 02:56:26 +00:00
|
|
|
NULL, NULL, NULL, NULL, LZMA_COMPRESSION, "lzma", 0
|
2009-10-14 02:58:11 +00:00
|
|
|
};
|
|
|
|
|
2014-11-27 18:48:44 +00:00
|
|
|
#ifndef CONFIG_SQUASHFS_LZ4
|
|
|
|
static const struct squashfs_decompressor squashfs_lz4_comp_ops = {
|
|
|
|
NULL, NULL, NULL, NULL, LZ4_COMPRESSION, "lz4", 0
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
2010-08-05 01:29:59 +00:00
|
|
|
#ifndef CONFIG_SQUASHFS_LZO
|
2011-01-05 18:23:53 +00:00
|
|
|
static const struct squashfs_decompressor squashfs_lzo_comp_ops = {
|
2013-11-13 02:56:26 +00:00
|
|
|
NULL, NULL, NULL, NULL, LZO_COMPRESSION, "lzo", 0
|
2009-10-14 02:58:11 +00:00
|
|
|
};
|
2010-08-05 01:29:59 +00:00
|
|
|
#endif
|
2009-10-14 02:58:11 +00:00
|
|
|
|
2010-12-09 02:08:31 +00:00
|
|
|
#ifndef CONFIG_SQUASHFS_XZ
|
|
|
|
static const struct squashfs_decompressor squashfs_xz_comp_ops = {
|
2013-11-13 02:56:26 +00:00
|
|
|
NULL, NULL, NULL, NULL, XZ_COMPRESSION, "xz", 0
|
2010-12-09 02:08:31 +00:00
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
2011-07-22 02:01:28 +00:00
|
|
|
#ifndef CONFIG_SQUASHFS_ZLIB
|
|
|
|
static const struct squashfs_decompressor squashfs_zlib_comp_ops = {
|
2013-11-13 02:56:26 +00:00
|
|
|
NULL, NULL, NULL, NULL, ZLIB_COMPRESSION, "zlib", 0
|
2011-07-22 02:01:28 +00:00
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
2017-08-10 02:42:36 +00:00
|
|
|
#ifndef CONFIG_SQUASHFS_ZSTD
|
|
|
|
static const struct squashfs_decompressor squashfs_zstd_comp_ops = {
|
|
|
|
NULL, NULL, NULL, NULL, ZSTD_COMPRESSION, "zstd", 0
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
2009-10-06 03:04:15 +00:00
|
|
|
static const struct squashfs_decompressor squashfs_unknown_comp_ops = {
|
2013-11-13 02:56:26 +00:00
|
|
|
NULL, NULL, NULL, NULL, 0, "unknown", 0
|
2009-10-06 03:04:15 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
static const struct squashfs_decompressor *decompressor[] = {
|
|
|
|
&squashfs_zlib_comp_ops,
|
2014-11-27 18:48:44 +00:00
|
|
|
&squashfs_lz4_comp_ops,
|
2010-08-05 01:29:59 +00:00
|
|
|
&squashfs_lzo_comp_ops,
|
2010-12-09 02:08:31 +00:00
|
|
|
&squashfs_xz_comp_ops,
|
2011-01-05 18:23:53 +00:00
|
|
|
&squashfs_lzma_unsupported_comp_ops,
|
2017-08-10 02:42:36 +00:00
|
|
|
&squashfs_zstd_comp_ops,
|
2009-10-06 03:04:15 +00:00
|
|
|
&squashfs_unknown_comp_ops
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
const struct squashfs_decompressor *squashfs_lookup_decompressor(int id)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
for (i = 0; decompressor[i]->id; i++)
|
|
|
|
if (id == decompressor[i]->id)
|
|
|
|
break;
|
|
|
|
|
|
|
|
return decompressor[i];
|
|
|
|
}
|
2011-02-28 01:45:42 +00:00
|
|
|
|
|
|
|
|
2013-11-13 02:56:26 +00:00
|
|
|
static void *get_comp_opts(struct super_block *sb, unsigned short flags)
|
2011-02-28 01:45:42 +00:00
|
|
|
{
|
|
|
|
struct squashfs_sb_info *msblk = sb->s_fs_info;
|
2013-11-13 02:56:26 +00:00
|
|
|
void *buffer = NULL, *comp_opts;
|
2013-11-18 02:59:12 +00:00
|
|
|
struct squashfs_page_actor *actor = NULL;
|
2011-02-28 01:45:42 +00:00
|
|
|
int length = 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Read decompressor specific options from file system if present
|
|
|
|
*/
|
|
|
|
if (SQUASHFS_COMP_OPTS(flags)) {
|
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 12:29:47 +00:00
|
|
|
buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
2013-11-13 02:56:26 +00:00
|
|
|
if (buffer == NULL) {
|
|
|
|
comp_opts = ERR_PTR(-ENOMEM);
|
|
|
|
goto out;
|
|
|
|
}
|
2011-02-28 01:45:42 +00:00
|
|
|
|
2013-11-18 02:59:12 +00:00
|
|
|
actor = squashfs_page_actor_init(&buffer, 1, 0);
|
|
|
|
if (actor == NULL) {
|
|
|
|
comp_opts = ERR_PTR(-ENOMEM);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
length = squashfs_read_data(sb,
|
|
|
|
sizeof(struct squashfs_super_block), 0, NULL, actor);
|
2011-02-28 01:45:42 +00:00
|
|
|
|
|
|
|
if (length < 0) {
|
2013-11-13 02:56:26 +00:00
|
|
|
comp_opts = ERR_PTR(length);
|
|
|
|
goto out;
|
2011-02-28 01:45:42 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2013-11-13 02:56:26 +00:00
|
|
|
comp_opts = squashfs_comp_opts(msblk, buffer, length);
|
2011-02-28 01:45:42 +00:00
|
|
|
|
2013-11-13 02:56:26 +00:00
|
|
|
out:
|
2013-11-18 02:59:12 +00:00
|
|
|
kfree(actor);
|
2011-02-28 01:45:42 +00:00
|
|
|
kfree(buffer);
|
2013-11-13 02:56:26 +00:00
|
|
|
return comp_opts;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void *squashfs_decompressor_setup(struct super_block *sb, unsigned short flags)
|
|
|
|
{
|
|
|
|
struct squashfs_sb_info *msblk = sb->s_fs_info;
|
|
|
|
void *stream, *comp_opts = get_comp_opts(sb, flags);
|
|
|
|
|
|
|
|
if (IS_ERR(comp_opts))
|
|
|
|
return comp_opts;
|
|
|
|
|
|
|
|
stream = squashfs_decompressor_create(msblk, comp_opts);
|
|
|
|
if (IS_ERR(stream))
|
|
|
|
kfree(comp_opts);
|
2011-02-28 01:45:42 +00:00
|
|
|
|
2013-11-13 02:56:26 +00:00
|
|
|
return stream;
|
2011-02-28 01:45:42 +00:00
|
|
|
}
|