60a726e333
When we initialized zcomp with single, we couldn't change max_comp_streams without zram reset but current interface doesn't show any error to user and even it changes max_comp_streams's value without any effect so it would make user very confusing. This patch prevents max_comp_streams's change when zcomp was initialized as single zcomp and emit the error to user(ex, echo). [akpm@linux-foundation.org: don't return with the lock held, per Sergey] [fengguang.wu@intel.com: fix coccinelle warnings] Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchan@redhat.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
69 lines
1.9 KiB
C
69 lines
1.9 KiB
C
/*
|
|
* Copyright (C) 2014 Sergey Senozhatsky.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _ZCOMP_H_
|
|
#define _ZCOMP_H_
|
|
|
|
#include <linux/mutex.h>
|
|
|
|
struct zcomp_strm {
|
|
/* compression/decompression buffer */
|
|
void *buffer;
|
|
/*
|
|
* The private data of the compression stream, only compression
|
|
* stream backend can touch this (e.g. compression algorithm
|
|
* working memory)
|
|
*/
|
|
void *private;
|
|
/* used in multi stream backend, protected by backend strm_lock */
|
|
struct list_head list;
|
|
};
|
|
|
|
/* static compression backend */
|
|
struct zcomp_backend {
|
|
int (*compress)(const unsigned char *src, unsigned char *dst,
|
|
size_t *dst_len, void *private);
|
|
|
|
int (*decompress)(const unsigned char *src, size_t src_len,
|
|
unsigned char *dst);
|
|
|
|
void *(*create)(void);
|
|
void (*destroy)(void *private);
|
|
|
|
const char *name;
|
|
};
|
|
|
|
/* dynamic per-device compression frontend */
|
|
struct zcomp {
|
|
void *stream;
|
|
struct zcomp_backend *backend;
|
|
|
|
struct zcomp_strm *(*strm_find)(struct zcomp *comp);
|
|
void (*strm_release)(struct zcomp *comp, struct zcomp_strm *zstrm);
|
|
bool (*set_max_streams)(struct zcomp *comp, int num_strm);
|
|
void (*destroy)(struct zcomp *comp);
|
|
};
|
|
|
|
ssize_t zcomp_available_show(const char *comp, char *buf);
|
|
|
|
struct zcomp *zcomp_create(const char *comp, int max_strm);
|
|
void zcomp_destroy(struct zcomp *comp);
|
|
|
|
struct zcomp_strm *zcomp_strm_find(struct zcomp *comp);
|
|
void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm);
|
|
|
|
int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
|
|
const unsigned char *src, size_t *dst_len);
|
|
|
|
int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
|
|
size_t src_len, unsigned char *dst);
|
|
|
|
bool zcomp_set_max_streams(struct zcomp *comp, int num_strm);
|
|
#endif /* _ZCOMP_H_ */
|