tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2014 Sergey Senozhatsky.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
9
10#ifndef _ZCOMP_H_
11#define _ZCOMP_H_
12
13#include <linux/mutex.h>
14
15struct zcomp_strm {
16 /* compression/decompression buffer */
17 void *buffer;
18 /*
19 * The private data of the compression stream, only compression
20 * stream backend can touch this (e.g. compression algorithm
21 * working memory)
22 */
23 void *private;
24 /* used in multi stream backend, protected by backend strm_lock */
25 struct list_head list;
26};
27
28/* static compression backend */
29struct zcomp_backend {
30 int (*compress)(const unsigned char *src, unsigned char *dst,
31 size_t *dst_len, void *private);
32
33 int (*decompress)(const unsigned char *src, size_t src_len,
34 unsigned char *dst);
35
36 void *(*create)(gfp_t flags);
37 void (*destroy)(void *private);
38
39 const char *name;
40};
41
42/* dynamic per-device compression frontend */
43struct zcomp {
44 void *stream;
45 struct zcomp_backend *backend;
46
47 struct zcomp_strm *(*strm_find)(struct zcomp *comp);
48 void (*strm_release)(struct zcomp *comp, struct zcomp_strm *zstrm);
49 bool (*set_max_streams)(struct zcomp *comp, int num_strm);
50 void (*destroy)(struct zcomp *comp);
51};
52
53ssize_t zcomp_available_show(const char *comp, char *buf);
54bool zcomp_available_algorithm(const char *comp);
55
56struct zcomp *zcomp_create(const char *comp, int max_strm);
57void zcomp_destroy(struct zcomp *comp);
58
59struct zcomp_strm *zcomp_strm_find(struct zcomp *comp);
60void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm);
61
62int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
63 const unsigned char *src, size_t *dst_len);
64
65int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
66 size_t src_len, unsigned char *dst);
67
68bool zcomp_set_max_streams(struct zcomp *comp, int num_strm);
69#endif /* _ZCOMP_H_ */