xref: /linux/drivers/block/zram/zcomp.h (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 struct zcomp_strm {
14 	/* compression/decompression buffer */
15 	void *buffer;
16 	struct crypto_comp *tfm;
17 };
18 
19 /* dynamic per-device compression frontend */
20 struct zcomp {
21 	struct zcomp_strm * __percpu *stream;
22 	struct notifier_block notifier;
23 
24 	const char *name;
25 };
26 
27 ssize_t zcomp_available_show(const char *comp, char *buf);
28 bool zcomp_available_algorithm(const char *comp);
29 
30 struct zcomp *zcomp_create(const char *comp);
31 void zcomp_destroy(struct zcomp *comp);
32 
33 struct zcomp_strm *zcomp_stream_get(struct zcomp *comp);
34 void zcomp_stream_put(struct zcomp *comp);
35 
36 int zcomp_compress(struct zcomp_strm *zstrm,
37 		const void *src, unsigned int *dst_len);
38 
39 int zcomp_decompress(struct zcomp_strm *zstrm,
40 		const void *src, unsigned int src_len, void *dst);
41 
42 bool zcomp_set_max_streams(struct zcomp *comp, int num_strm);
43 #endif /* _ZCOMP_H_ */
44