zstd/contrib/linux-kernel/zstd_compress_module.c
2020-12-02 11:07:38 -08:00

207 lines
6.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/zstd.h>
#include "zstd.h"
#include "common/zstd_deps.h"
#include "common/zstd_internal.h"
static void zstd_check_structs(void) {
/* Check that the structs have the same size. */
ZSTD_STATIC_ASSERT(sizeof(ZSTD_parameters) ==
sizeof(struct zstd_parameters));
ZSTD_STATIC_ASSERT(sizeof(ZSTD_compressionParameters) ==
sizeof(struct zstd_compression_parameters));
ZSTD_STATIC_ASSERT(sizeof(ZSTD_frameParameters) ==
sizeof(struct zstd_frame_parameters));
/* Zstd guarantees that the layout of the structs never change. Verify it. */
ZSTD_STATIC_ASSERT(offsetof(ZSTD_parameters, cParams) ==
offsetof(struct zstd_parameters, cparams));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_parameters, fParams) ==
offsetof(struct zstd_parameters, fparams));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, windowLog) ==
offsetof(struct zstd_compression_parameters, window_log));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, chainLog) ==
offsetof(struct zstd_compression_parameters, chain_log));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, hashLog) ==
offsetof(struct zstd_compression_parameters, hash_log));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, searchLog) ==
offsetof(struct zstd_compression_parameters, search_log));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, minMatch) ==
offsetof(struct zstd_compression_parameters, search_length));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, targetLength) ==
offsetof(struct zstd_compression_parameters, target_length));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_compressionParameters, strategy) ==
offsetof(struct zstd_compression_parameters, strategy));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_frameParameters, contentSizeFlag) ==
offsetof(struct zstd_frame_parameters, content_size_flag));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_frameParameters, checksumFlag) ==
offsetof(struct zstd_frame_parameters, checksum_flag));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_frameParameters, noDictIDFlag) ==
offsetof(struct zstd_frame_parameters, no_dict_id_flag));
/* Check that the strategies are the same. This can change. */
ZSTD_STATIC_ASSERT((int)ZSTD_fast == (int)zstd_fast);
ZSTD_STATIC_ASSERT((int)ZSTD_dfast == (int)zstd_dfast);
ZSTD_STATIC_ASSERT((int)ZSTD_greedy == (int)zstd_greedy);
ZSTD_STATIC_ASSERT((int)ZSTD_lazy == (int)zstd_lazy);
ZSTD_STATIC_ASSERT((int)ZSTD_lazy2 == (int)zstd_lazy2);
ZSTD_STATIC_ASSERT((int)ZSTD_btlazy2 == (int)zstd_btlazy2);
ZSTD_STATIC_ASSERT((int)ZSTD_btopt == (int)zstd_btopt);
ZSTD_STATIC_ASSERT((int)ZSTD_btultra == (int)zstd_btultra);
ZSTD_STATIC_ASSERT((int)ZSTD_btultra2 == (int)zstd_btultra2);
/* Check input buffer */
ZSTD_STATIC_ASSERT(sizeof(ZSTD_inBuffer) == sizeof(struct zstd_in_buffer));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_inBuffer, src) ==
offsetof(struct zstd_in_buffer, src));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_inBuffer, size) ==
offsetof(struct zstd_in_buffer, size));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_inBuffer, pos) ==
offsetof(struct zstd_in_buffer, pos));
/* Check output buffer */
ZSTD_STATIC_ASSERT(sizeof(ZSTD_outBuffer) ==
sizeof(struct zstd_out_buffer));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_outBuffer, dst) ==
offsetof(struct zstd_out_buffer, dst));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_outBuffer, size) ==
offsetof(struct zstd_out_buffer, size));
ZSTD_STATIC_ASSERT(offsetof(ZSTD_outBuffer, pos) ==
offsetof(struct zstd_out_buffer, pos));
}
size_t zstd_compress_bound(size_t src_size)
{
return ZSTD_compressBound(src_size);
}
EXPORT_SYMBOL(zstd_compress_bound);
struct zstd_parameters zstd_get_params(int level,
unsigned long long estimated_src_size)
{
const ZSTD_parameters params = ZSTD_getParams(level, estimated_src_size, 0);
struct zstd_parameters out;
/* no-op */
zstd_check_structs();
ZSTD_memcpy(&out, &params, sizeof(out));
return out;
}
EXPORT_SYMBOL(zstd_get_params);
size_t zstd_cctx_workspace_bound(
const struct zstd_compression_parameters *cparams)
{
ZSTD_compressionParameters p;
ZSTD_memcpy(&p, cparams, sizeof(p));
return ZSTD_estimateCCtxSize_usingCParams(p);
}
EXPORT_SYMBOL(zstd_cctx_workspace_bound);
zstd_cctx *zstd_init_cctx(void *workspace, size_t workspace_size)
{
if (workspace == NULL)
return NULL;
return ZSTD_initStaticCCtx(workspace, workspace_size);
}
EXPORT_SYMBOL(zstd_init_cctx);
size_t zstd_compress_cctx(zstd_cctx *cctx, void *dst, size_t dst_capacity,
const void *src, size_t src_size, const struct zstd_parameters *parameters)
{
ZSTD_parameters p;
ZSTD_memcpy(&p, parameters, sizeof(p));
return ZSTD_compress_advanced(cctx, dst, dst_capacity, src, src_size, NULL, 0, p);
}
EXPORT_SYMBOL(zstd_compress_cctx);
size_t zstd_cstream_workspace_bound(
const struct zstd_compression_parameters *cparams)
{
ZSTD_compressionParameters p;
ZSTD_memcpy(&p, cparams, sizeof(p));
return ZSTD_estimateCStreamSize_usingCParams(p);
}
EXPORT_SYMBOL(zstd_cstream_workspace_bound);
zstd_cstream *zstd_init_cstream(const struct zstd_parameters *parameters,
unsigned long long pledged_src_size, void *workspace, size_t workspace_size)
{
ZSTD_parameters p;
zstd_cstream *cstream;
size_t ret;
if (workspace == NULL)
return NULL;
cstream = ZSTD_initStaticCStream(workspace, workspace_size);
if (cstream == NULL)
return NULL;
/* 0 means unknown in linux zstd API but means 0 in new zstd API */
if (pledged_src_size == 0)
pledged_src_size = ZSTD_CONTENTSIZE_UNKNOWN;
ZSTD_memcpy(&p, parameters, sizeof(p));
ret = ZSTD_initCStream_advanced(cstream, NULL, 0, p, pledged_src_size);
if (ZSTD_isError(ret))
return NULL;
return cstream;
}
EXPORT_SYMBOL(zstd_init_cstream);
size_t zstd_reset_cstream(zstd_cstream *cstream,
unsigned long long pledged_src_size)
{
return ZSTD_resetCStream(cstream, pledged_src_size);
}
EXPORT_SYMBOL(zstd_reset_cstream);
size_t zstd_compress_stream(zstd_cstream *cstream,
struct zstd_out_buffer *output, struct zstd_in_buffer *input)
{
ZSTD_outBuffer o;
ZSTD_inBuffer i;
size_t ret;
ZSTD_memcpy(&o, output, sizeof(o));
ZSTD_memcpy(&i, input, sizeof(i));
ret = ZSTD_compressStream(cstream, &o, &i);
ZSTD_memcpy(output, &o, sizeof(o));
ZSTD_memcpy(input, &i, sizeof(i));
return ret;
}
EXPORT_SYMBOL(zstd_compress_stream);
size_t zstd_flush_stream(zstd_cstream *cstream, struct zstd_out_buffer *output)
{
ZSTD_outBuffer o;
size_t ret;
ZSTD_memcpy(&o, output, sizeof(o));
ret = ZSTD_flushStream(cstream, &o);
ZSTD_memcpy(output, &o, sizeof(o));
return ret;
}
EXPORT_SYMBOL(zstd_flush_stream);
size_t zstd_end_stream(zstd_cstream *cstream, struct zstd_out_buffer *output)
{
ZSTD_outBuffer o;
size_t ret;
ZSTD_memcpy(&o, output, sizeof(o));
ret = ZSTD_endStream(cstream, &o);
ZSTD_memcpy(output, &o, sizeof(o));
return ret;
}
EXPORT_SYMBOL(zstd_end_stream);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("Zstd Compressor");