minio/pkg/encoding/erasure/ec-code.h

661 lines
27 KiB
C

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#ifndef _ERASURE_CODE_H_
#define _ERASURE_CODE_H_
#include <stdint.h>
/**
* @file erasure_code.h
* @brief Interface to functions supporting erasure code encode and decode.
*
* This file defines the interface to optimized functions used in erasure
* codes. Encode and decode of erasures in GF(2^8) are made by calculating the
* dot product of the symbols (bytes in GF(2^8)) across a set of buffers and a
* set of coefficients. Values for the coefficients are determined by the type
* of erasure code. Using a general dot product means that any sequence of
* coefficients may be used including erasure codes based on random
* coefficients.
* Multiple versions of dot product are supplied to calculate 1-6 output
* vectors in one pass.
* Base GF multiply and divide functions can be sped up by defining
* GF_LARGE_TABLES at the expense of memory size.
*
*/
#include "ec-vect-mul.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Initialize tables for fast Erasure Code encode and decode.
*
* Generates the expanded tables needed for fast encode or decode for erasure
* codes on blocks of data. 32bytes is generated for each input coefficient.
*
* @param k The number of vector sources or rows in the generator matrix
* for coding.
* @param rows The number of output vectors to concurrently encode/decode.
* @param a Pointer to sets of arrays of input coefficients used to encode
* or decode data.
* @param gftbls Pointer to start of space for concatenated output tables
* generated from input coefficients. Must be of size 32*k*rows.
* @returns none
*/
void ec_init_tables(int k, int rows, uint8_t* a, uint8_t* gftbls);
/**
* @brief Generate or decode erasure codes on blocks of data.
*
* Given a list of source data blocks, generate one or multiple blocks of
* encoded data as specified by a matrix of GF(2^8) coefficients. When given a
* suitable set of coefficients, this function will perform the fast generation
* or decoding of Reed-Solomon type erasure codes.
*
* @requires SSE4.1
* @param len Length of each block of data (vector) of source or dest data.
* @param k The number of vector sources or rows in the generator matrix
* for coding.
* @param rows The number of output vectors to concurrently encode/decode.
* @param gftbls Pointer to array of input tables generated from coding
* coefficients in ec_init_tables(). Must be of size 32*k*rows
* @param data Array of pointers to source input buffers.
* @param coding Array of pointers to coded output buffers.
* @returns none
*/
void ec_encode_data_sse(int len, int k, int rows, uint8_t *gftbls, uint8_t **data, uint8_t **coding);
/**
* @brief Generate or decode erasure codes on blocks of data, runs appropriate version.
*
* Given a list of source data blocks, generate one or multiple blocks of
* encoded data as specified by a matrix of GF(2^8) coefficients. When given a
* suitable set of coefficients, this function will perform the fast generation
* or decoding of Reed-Solomon type erasure codes.
*
* This function determines what instruction sets are enabled and
* selects the appropriate version at runtime.
*
* @param len Length of each block of data (vector) of source or dest data.
* @param k The number of vector sources or rows in the generator matrix
* for coding.
* @param rows The number of output vectors to concurrently encode/decode.
* @param gftbls Pointer to array of input tables generated from coding
* coefficients in ec_init_tables(). Must be of size 32*k*rows
* @param data Array of pointers to source input buffers.
* @param coding Array of pointers to coded output buffers.
* @returns none
*/
void ec_encode_data(int len, int k, int rows, uint8_t *gftbls, uint8_t **data, uint8_t **coding);
/**
* @brief Generate or decode erasure codes on blocks of data, runs baseline version.
*
* Given a list of source data blocks, generate one or multiple blocks of
* encoded data as specified by a matrix of GF(2^8) coefficients. When given a
* suitable set of coefficients, this function will perform the fast generation
* or decoding of Reed-Solomon type erasure codes.
*
* @param len Length of each block of data (vector) of source or dest data.
* @param srcs The number of vector sources or rows in the generator matrix
* for coding.
* @param dests The number of output vectors to concurrently encode/decode.
* @param v Pointer to array of input tables generated from coding
* coefficients in ec_init_tables(). Must be of size 32*k*rows
* @param src Array of pointers to source input buffers.
* @param dest Array of pointers to coded output buffers.
* @returns none
*/
void ec_encode_data_base(int len, int srcs, int dests, uint8_t *v, uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product.
*
* Does a GF(2^8) dot product across each byte of the input array and a constant
* set of coefficients to produce each byte of the output. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 32*vlen byte constant array based on the input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 32*vlen byte array of pre-calculated constants based
* on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Pointer to destination data array.
* @returns none
*/
void gf_vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t *dest);
/**
* @brief GF(2^8) vector dot product.
*
* Does a GF(2^8) dot product across each byte of the input array and a constant
* set of coefficients to produce each byte of the output. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 32*vlen byte constant array based on the input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 32*vlen byte array of pre-calculated constants based
* on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Pointer to destination data array.
* @returns none
*/
void gf_vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t *dest);
/**
* @brief GF(2^8) vector dot product.
*
* Does a GF(2^8) dot product across each byte of the input array and a constant
* set of coefficients to produce each byte of the output. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 32*vlen byte constant array based on the input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 32*vlen byte array of pre-calculated constants based
* on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Pointer to destination data array.
* @returns none
*/
void gf_vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t *dest);
/**
* @brief GF(2^8) vector dot product with two outputs.
*
* Vector dot product optimized to calculate two ouputs at a time. Does two
* GF(2^8) dot products across each byte of the input array and two constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 2*32*vlen byte constant array based on the two sets of input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 2*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_2vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with two outputs.
*
* Vector dot product optimized to calculate two ouputs at a time. Does two
* GF(2^8) dot products across each byte of the input array and two constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 2*32*vlen byte constant array based on the two sets of input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 2*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_2vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with two outputs.
*
* Vector dot product optimized to calculate two ouputs at a time. Does two
* GF(2^8) dot products across each byte of the input array and two constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 2*32*vlen byte constant array based on the two sets of input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 2*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_2vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with three outputs.
*
* Vector dot product optimized to calculate three ouputs at a time. Does three
* GF(2^8) dot products across each byte of the input array and three constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 3*32*vlen byte constant array based on the three sets of input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 3*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_3vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with three outputs.
*
* Vector dot product optimized to calculate three ouputs at a time. Does three
* GF(2^8) dot products across each byte of the input array and three constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 3*32*vlen byte constant array based on the three sets of input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 3*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_3vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with three outputs.
*
* Vector dot product optimized to calculate three ouputs at a time. Does three
* GF(2^8) dot products across each byte of the input array and three constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 3*32*vlen byte constant array based on the three sets of input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 3*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_3vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with four outputs.
*
* Vector dot product optimized to calculate four ouputs at a time. Does four
* GF(2^8) dot products across each byte of the input array and four constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 4*32*vlen byte constant array based on the four sets of input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 4*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_4vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with four outputs.
*
* Vector dot product optimized to calculate four ouputs at a time. Does four
* GF(2^8) dot products across each byte of the input array and four constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 4*32*vlen byte constant array based on the four sets of input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 4*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_4vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with four outputs.
*
* Vector dot product optimized to calculate four ouputs at a time. Does four
* GF(2^8) dot products across each byte of the input array and four constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 4*32*vlen byte constant array based on the four sets of input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 4*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_4vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with five outputs.
*
* Vector dot product optimized to calculate five ouputs at a time. Does five
* GF(2^8) dot products across each byte of the input array and five constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 5*32*vlen byte constant array based on the five sets of input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 5*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_5vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with five outputs.
*
* Vector dot product optimized to calculate five ouputs at a time. Does five
* GF(2^8) dot products across each byte of the input array and five constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 5*32*vlen byte constant array based on the five sets of input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 5*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_5vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with five outputs.
*
* Vector dot product optimized to calculate five ouputs at a time. Does five
* GF(2^8) dot products across each byte of the input array and five constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 5*32*vlen byte constant array based on the five sets of input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 5*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_5vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with six outputs.
*
* Vector dot product optimized to calculate six ouputs at a time. Does six
* GF(2^8) dot products across each byte of the input array and six constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 6*32*vlen byte constant array based on the six sets of input coefficients.
*
* @requires SSE4.1
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 6*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_6vect_dot_prod_sse(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with six outputs.
*
* Vector dot product optimized to calculate six ouputs at a time. Does six
* GF(2^8) dot products across each byte of the input array and six constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 6*32*vlen byte constant array based on the six sets of input coefficients.
*
* @requires AVX
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 6*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_6vect_dot_prod_avx(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product with six outputs.
*
* Vector dot product optimized to calculate six ouputs at a time. Does six
* GF(2^8) dot products across each byte of the input array and six constant
* sets of coefficients to produce each byte of the outputs. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 6*32*vlen byte constant array based on the six sets of input coefficients.
*
* @requires AVX2
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 6*32*vlen byte array of pre-calculated constants
* based on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Array of pointers to destination data buffers.
* @returns none
*/
void gf_6vect_dot_prod_avx2(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t **dest);
/**
* @brief GF(2^8) vector dot product, runs baseline version.
*
* Does a GF(2^8) dot product across each byte of the input array and a constant
* set of coefficients to produce each byte of the output. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 32*vlen byte constant array based on the input coefficients.
*
* @param len Length of each vector in bytes. Must be >= 16.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 32*vlen byte array of pre-calculated constants based
* on the array of input coefficients. Only elements 32*CONST*j + 1
* of this array are used, where j = (0, 1, 2...) and CONST is the
* number of elements in the array of input coefficients. The
* elements used correspond to the original input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Pointer to destination data array.
* @returns none
*/
void gf_vect_dot_prod_base(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t *dest);
/**
* @brief GF(2^8) vector dot product, runs appropriate version.
*
* Does a GF(2^8) dot product across each byte of the input array and a constant
* set of coefficients to produce each byte of the output. Can be used for
* erasure coding encode and decode. Function requires pre-calculation of a
* 32*vlen byte constant array based on the input coefficients.
*
* This function determines what instruction sets are enabled and
* selects the appropriate version at runtime.
*
* @param len Length of each vector in bytes. Must be >= 32.
* @param vlen Number of vector sources.
* @param gftbls Pointer to 32*vlen byte array of pre-calculated constants based
* on the array of input coefficients.
* @param src Array of pointers to source inputs.
* @param dest Pointer to destination data array.
* @returns none
*/
void gf_vect_dot_prod(int len, int vlen, uint8_t *gftbls,
uint8_t **src, uint8_t *dest);
/**********************************************************************
* The remaining are lib support functions used in GF(2^8) operations.
*/
/**
* @brief Single element GF(2^8) multiply.
*
* @param a Multiplicand a
* @param b Multiplicand b
* @returns Product of a and b in GF(2^8)
*/
uint8_t gf_mul(uint8_t a, uint8_t b);
/**
* @brief Single element GF(2^8) inverse.
*
* @param a Input element
* @returns Field element b such that a x b = {1}
*/
uint8_t gf_inv(uint8_t a);
/**
* @brief Generate a matrix of coefficients to be used for encoding.
*
* Vandermonde matrix example of encoding coefficients where high portion of
* matrix is identity matrix I and lower portion is constructed as 2^{i*(j-k+1)}
* i:{0,k-1} j:{k,m-1}. Commonly used method for choosing coefficients in
* erasure encoding but does not guarantee invertable for every sub matrix. For
* large k it is possible to find cases where the decode matrix chosen from
* sources and parity not in erasure are not invertable. Users may want to
* adjust for k > 5.
*
* @param a [mxk] array to hold coefficients
* @param m number of rows in matrix corresponding to srcs + parity.
* @param k number of columns in matrix corresponding to srcs.
* @returns none
*/
void gf_gen_rs_matrix(uint8_t *a, int m, int k);
/**
* @brief Generate a Cauchy matrix of coefficients to be used for encoding.
*
* Cauchy matrix example of encoding coefficients where high portion of matrix
* is identity matrix I and lower portion is constructed as 1/(i + j) | i != j,
* i:{0,k-1} j:{k,m-1}. Any sub-matrix of a Cauchy matrix should be invertable.
*
* @param a [mxk] array to hold coefficients
* @param m number of rows in matrix corresponding to srcs + parity.
* @param k number of columns in matrix corresponding to srcs.
* @returns none
*/
void gf_gen_cauchy1_matrix(uint8_t *a, int m, int k);
/**
* @brief Invert a matrix in GF(2^8)
*
* @param in input matrix
* @param out output matrix such that [in] x [out] = [I] - identity matrix
* @param n size of matrix [nxn]
* @returns 0 successful, other fail on singular input matrix
*/
int gf_invert_matrix(uint8_t *in, uint8_t *out, const int n);
/*************************************************************/
#ifdef __cplusplus
}
#endif
#endif //_ERASURE_CODE_H_