compress.h
1.41 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2019 HUAWEI, Inc.
* https://www.huawei.com/
* Created by Gao Xiang <gaoxiang25@huawei.com>
*/
#ifndef __EROFS_FS_COMPRESS_H
#define __EROFS_FS_COMPRESS_H
#include "internal.h"
enum {
Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
Z_EROFS_COMPRESSION_RUNTIME_MAX
};
struct z_erofs_decompress_req {
struct super_block *sb;
struct page **in, **out;
unsigned short pageofs_out;
unsigned int inputsize, outputsize;
/* indicate the algorithm will be used for decompression */
unsigned int alg;
bool inplace_io, partial_decoding;
};
/*
* - 0x5A110C8D ('sallocated', Z_EROFS_MAPPING_STAGING) -
* used to mark temporary allocated pages from other
* file/cached pages and NULL mapping pages.
*/
#define Z_EROFS_MAPPING_STAGING ((void *)0x5A110C8D)
/* check if a page is marked as staging */
static inline bool z_erofs_page_is_staging(struct page *page)
{
return page->mapping == Z_EROFS_MAPPING_STAGING;
}
static inline bool z_erofs_put_stagingpage(struct list_head *pagepool,
struct page *page)
{
if (!z_erofs_page_is_staging(page))
return false;
/* staging pages should not be used by others at the same time */
if (page_ref_count(page) > 1)
put_page(page);
else
list_add(&page->lru, pagepool);
return true;
}
int z_erofs_decompress(struct z_erofs_decompress_req *rq,
struct list_head *pagepool);
#endif