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#include <linux/kernel.h>
#include <linux/lz4.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "backend_lz4hc.h"
struct lz4hc_ctx {
void *mem;
s32 level;
};
static void lz4hc_destroy(void *ctx)
{
struct lz4hc_ctx *zctx = ctx;
vfree(zctx->mem);
kfree(zctx);
}
static void *lz4hc_create(void)
{
struct lz4hc_ctx *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return NULL;
/* @FIXME: using a hardcoded LZ4HC_DEFAULT_CLEVEL for now */
ctx->level = LZ4HC_DEFAULT_CLEVEL;
ctx->mem = vmalloc(LZ4HC_MEM_COMPRESS);
if (!ctx->mem)
goto error;
return ctx;
error:
lz4hc_destroy(ctx);
return NULL;
}
static int lz4hc_compress(void *ctx, const unsigned char *src, size_t src_len,
unsigned char *dst, size_t *dst_len)
{
struct lz4hc_ctx *zctx = ctx;
int ret;
ret = LZ4_compress_HC(src, dst, src_len, *dst_len,
zctx->level, zctx->mem);
if (!ret)
return -EINVAL;
*dst_len = ret;
return 0;
}
static int lz4hc_decompress(void *ctx, const unsigned char *src,
size_t src_len, unsigned char *dst, size_t dst_len)
{
int ret;
ret = LZ4_decompress_safe(src, dst, src_len, dst_len);
if (ret < 0)
return -EINVAL;
return 0;
}
const struct zcomp_ops backend_lz4hc = {
.compress = lz4hc_compress,
.decompress = lz4hc_decompress,
.create_ctx = lz4hc_create,
.destroy_ctx = lz4hc_destroy,
.name = "lz4hc",
};
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