xref: /openbmc/linux/drivers/block/zram/zcomp.h (revision 2cf1c348)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2014 Sergey Senozhatsky.
4  */
5 
6 #ifndef _ZCOMP_H_
7 #define _ZCOMP_H_
8 #include <linux/local_lock.h>
9 
10 struct zcomp_strm {
11 	/* The members ->buffer and ->tfm are protected by ->lock. */
12 	local_lock_t lock;
13 	/* compression/decompression buffer */
14 	void *buffer;
15 	struct crypto_comp *tfm;
16 };
17 
18 /* dynamic per-device compression frontend */
19 struct zcomp {
20 	struct zcomp_strm __percpu *stream;
21 	const char *name;
22 	struct hlist_node node;
23 };
24 
25 int zcomp_cpu_up_prepare(unsigned int cpu, struct hlist_node *node);
26 int zcomp_cpu_dead(unsigned int cpu, struct hlist_node *node);
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