blob: 8836e0c785ba72427faab6e1921c088120233a20 [file] [log] [blame] [edit]
// SPDX-License-Identifier: GPL-2.0+
/*
* erofs-utils/lib/compressor.c
*
* Copyright (C) 2018-2019 HUAWEI, Inc.
* http://www.huawei.com/
* Created by Gao Xiang <gaoxiang25@huawei.com>
*/
#include "erofs/internal.h"
#include "compressor.h"
#include "erofs/print.h"
#define EROFS_CONFIG_COMPR_DEF_BOUNDARY (128)
static struct erofs_compressor *compressors[] = {
#if LZ4_ENABLED
#if LZ4HC_ENABLED
&erofs_compressor_lz4hc,
#endif
&erofs_compressor_lz4,
#endif
};
int erofs_compress_destsize(struct erofs_compress *c,
int compression_level,
void *src,
unsigned int *srcsize,
void *dst,
unsigned int dstsize)
{
unsigned uncompressed_size;
int ret;
DBG_BUGON(!c->alg);
if (!c->alg->compress_destsize)
return -ENOTSUP;
ret = c->alg->compress_destsize(c, compression_level,
src, srcsize, dst, dstsize);
if (ret < 0)
return ret;
/* check if there is enough gains to compress */
uncompressed_size = *srcsize;
if (roundup(ret, EROFS_BLKSIZ) >= uncompressed_size *
c->compress_threshold / 100)
return -EAGAIN;
return ret;
}
const char *z_erofs_list_available_compressors(unsigned int i)
{
return i >= ARRAY_SIZE(compressors) ? NULL : compressors[i]->name;
}
int erofs_compressor_init(struct erofs_compress *c, char *alg_name)
{
int ret, i;
/* should be written in "minimum compression ratio * 100" */
c->compress_threshold = 100;
/* optimize for 4k size page */
c->destsize_alignsize = PAGE_SIZE;
c->destsize_redzone_begin = PAGE_SIZE - 16;
c->destsize_redzone_end = EROFS_CONFIG_COMPR_DEF_BOUNDARY;
if (!alg_name) {
c->alg = NULL;
return 0;
}
ret = -EINVAL;
for (i = 0; i < ARRAY_SIZE(compressors); ++i) {
if (alg_name && strcmp(alg_name, compressors[i]->name))
continue;
ret = compressors[i]->init(c);
if (!ret) {
DBG_BUGON(!c->alg);
return 0;
}
}
erofs_err("Cannot find a valid compressor %s", alg_name);
return ret;
}
int erofs_compressor_exit(struct erofs_compress *c)
{
if (c->alg && c->alg->exit)
return c->alg->exit(c);
return 0;
}