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06af1c52c9
The current lz4 compress buffer is 16kb on 32-bits, 32kb on 64-bits system. But, lz4 needs only 16kb on both. On 64-bits, this causes wasted cpu cycles for additional memset during every compression. In case of lz4hc, the current buffer size is (256kb + 8) on 32-bits, (512kb + 16) on 64-bits. But, lz4hc needs only (256kb + 2 * pointer) on both. This patch fixes these wrong compress buffer sizes for 64-bits. Signed-off-by: Bongkyu Kim <bongkyu.kim@lge.com> Cc: Chanho Min <chanho.min@lge.com> Cc: Yann Collet <yann.collet.73@gmail.com> Cc: Kyungsik Lee <kyungsik.lee@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
87 lines
3.1 KiB
C
87 lines
3.1 KiB
C
#ifndef __LZ4_H__
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#define __LZ4_H__
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/*
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* LZ4 Kernel Interface
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*
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* Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#define LZ4_MEM_COMPRESS (16384)
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#define LZ4HC_MEM_COMPRESS (262144 + (2 * sizeof(unsigned char *)))
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/*
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* lz4_compressbound()
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* Provides the maximum size that LZ4 may output in a "worst case" scenario
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* (input data not compressible)
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*/
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static inline size_t lz4_compressbound(size_t isize)
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{
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return isize + (isize / 255) + 16;
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}
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/*
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* lz4_compress()
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* src : source address of the original data
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* src_len : size of the original data
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* dst : output buffer address of the compressed data
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* This requires 'dst' of size LZ4_COMPRESSBOUND.
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* dst_len : is the output size, which is returned after compress done
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* workmem : address of the working memory.
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* This requires 'workmem' of size LZ4_MEM_COMPRESS.
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* return : Success if return 0
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* Error if return (< 0)
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* note : Destination buffer and workmem must be already allocated with
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* the defined size.
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*/
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int lz4_compress(const unsigned char *src, size_t src_len,
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unsigned char *dst, size_t *dst_len, void *wrkmem);
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/*
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* lz4hc_compress()
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* src : source address of the original data
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* src_len : size of the original data
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* dst : output buffer address of the compressed data
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* This requires 'dst' of size LZ4_COMPRESSBOUND.
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* dst_len : is the output size, which is returned after compress done
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* workmem : address of the working memory.
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* This requires 'workmem' of size LZ4HC_MEM_COMPRESS.
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* return : Success if return 0
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* Error if return (< 0)
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* note : Destination buffer and workmem must be already allocated with
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* the defined size.
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*/
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int lz4hc_compress(const unsigned char *src, size_t src_len,
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unsigned char *dst, size_t *dst_len, void *wrkmem);
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/*
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* lz4_decompress()
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* src : source address of the compressed data
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* src_len : is the input size, whcih is returned after decompress done
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* dest : output buffer address of the decompressed data
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* actual_dest_len: is the size of uncompressed data, supposing it's known
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* return : Success if return 0
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* Error if return (< 0)
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* note : Destination buffer must be already allocated.
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* slightly faster than lz4_decompress_unknownoutputsize()
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*/
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int lz4_decompress(const unsigned char *src, size_t *src_len,
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unsigned char *dest, size_t actual_dest_len);
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/*
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* lz4_decompress_unknownoutputsize()
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* src : source address of the compressed data
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* src_len : is the input size, therefore the compressed size
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* dest : output buffer address of the decompressed data
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* dest_len: is the max size of the destination buffer, which is
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* returned with actual size of decompressed data after
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* decompress done
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* return : Success if return 0
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* Error if return (< 0)
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* note : Destination buffer must be already allocated.
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*/
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int lz4_decompress_unknownoutputsize(const unsigned char *src, size_t src_len,
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unsigned char *dest, size_t *dest_len);
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#endif
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