/* * Copyright (C) 2013 Andrea Mazzoleni * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #ifndef __RAID_H #define __RAID_H /****************************************************************************/ /* raid */ /** * RAID mode supporting up to 6 parities. * * It requires SSSE3 to get good performance with triple or more * parities. * * This is the default mode used by SnapRAID. */ #define RAID_MODE_CAUCHY 0 /** * RAID mode supporting up to 3 parities, * * It has a fast triple parity implementation even without SSSE3, but it * cannot go beyond it. * This is mostly intended for low end CPUs like ARM and AMD Athlon. */ #define RAID_MODE_VANDERMONDE 1 /** * Max level of parity supported for RAID_MODE_CAUCHY. */ #define RAID_PARITY_CAUCHY_MAX 6 /** * Max level of parity supported for RAID_MODE_VANDERMONDE. */ #define RAID_PARITY_VANDERMONDE_MAX 3 /** * Maximum number of data disks. * Limit of the parity generator matrix used. */ #define RAID_DATA_MAX 251 /** * Minimum number of data disks. * Some optimizations require at least two disks. */ #define RAID_DATA_MIN 2 /** * Initializes the RAID system. */ void raid_init(void); /** * Set the RAID mode to use. One of RAID_MODE_*. * * You can change mode at any time, and it will affect next calls to raid_par() and raid_rec(). * * The two modes are compatible for the first two levels of parity. The third one is different. */ void raid_set(unsigned mode); /** * Computes the parity. * * \param level Number of parities to compute. * \param vbuf Vector of pointers to the blocks for disks and parities. * It has (::data + ::level) elements. Each element points to a buffer of ::size bytes. * \param data Number of data disks. * \param size Size of the blocks pointed by vbuf. It must be a power of 2, and at least 64. */ void raid_par(unsigned level, unsigned char** vbuf, unsigned data, unsigned size); /** * Recovers failures of data disks using the specified parities. * * Note that only the data blocks are recovered. The parity is destroyed. * \param level Number of failed disks. * \param d[] Vector of indexes of the data disks to recover. Starting from 0. * \param c[] Vector of indexes of the checksum/parity to use for the recovering. Starting from 0. * \param vbuf Vector of pointers to the blocks for disks and parities. * It has (::data + max(::c[] + 1)) elements. Each element points to a buffer of ::size bytes. * \param data Number of data disks. * \param zero Buffer filled with 0 of ::size bytes. This buffer is not modified. * \param size Size of the blocks pointed by vbuf. It must be a power of 2, and at least 64. */ void raid_rec(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); /** * Gets the name of the selected function to compute the parity. * Only for testing. */ const char* raid_par1_tag(void); const char* raid_par2_tag(void); const char* raid_parz_tag(void); const char* raid_par3_tag(void); const char* raid_par4_tag(void); const char* raid_par5_tag(void); const char* raid_par6_tag(void); const char* raid_rec1_tag(void); const char* raid_rec2_tag(void); const char* raid_recX_tag(void); /** * Specialized parity computation. * Only for testing. */ void raid_par1_int32(unsigned char** vbuf, unsigned data, unsigned size); void raid_par1_int64(unsigned char** vbuf, unsigned data, unsigned size); void raid_par1_sse2(unsigned char** vbuf, unsigned data, unsigned size); void raid_par2_int32(unsigned char** vbuf, unsigned data, unsigned size); void raid_par2_int64(unsigned char** vbuf, unsigned data, unsigned size); void raid_par2_sse2(unsigned char** vbuf, unsigned data, unsigned size); void raid_par2_sse2ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_parz_int32(unsigned char** vbuf, unsigned data, unsigned size); void raid_parz_int64(unsigned char** vbuf, unsigned data, unsigned size); void raid_parz_sse2(unsigned char** vbuf, unsigned data, unsigned size); void raid_parz_sse2ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_par3_int8(unsigned char** vbuf, unsigned data, unsigned size); void raid_par3_ssse3(unsigned char** vbuf, unsigned data, unsigned size); void raid_par3_ssse3ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_par4_int8(unsigned char** vbuf, unsigned data, unsigned size); void raid_par4_ssse3(unsigned char** vbuf, unsigned data, unsigned size); void raid_par4_ssse3ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_par5_int8(unsigned char** vbuf, unsigned data, unsigned size); void raid_par5_ssse3(unsigned char** vbuf, unsigned data, unsigned size); void raid_par5_ssse3ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_par6_int8(unsigned char** vbuf, unsigned data, unsigned size); void raid_par6_ssse3(unsigned char** vbuf, unsigned data, unsigned size); void raid_par6_ssse3ext(unsigned char** vbuf, unsigned data, unsigned size); void raid_rec1_int8(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); void raid_rec2_int8(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); void raid_recX_int8(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); void raid_rec1_ssse3(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); void raid_rec2_ssse3(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); void raid_recX_ssse3(unsigned level, const int* d, const int* c, unsigned char** vbuf, unsigned data, unsigned char* zero, unsigned size); #endif