1/* -*- linux-c -*- ------------------------------------------------------- * 2 * 3 * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation, Inc., 53 Temple Place Ste 330, 8 * Boston MA 02111-1307, USA; either version 2 of the License, or 9 * (at your option) any later version; incorporated herein by reference. 10 * 11 * ----------------------------------------------------------------------- */ 12 13/* 14 * int$#.c 15 * 16 * $#-way unrolled portable integer math RAID-6 instruction set 17 * 18 * This file is postprocessed using unroll.awk 19 */ 20 21#include <linux/raid/pq.h> 22 23/* 24 * This is the C data type to use 25 */ 26 27/* Change this from BITS_PER_LONG if there is something better... */ 28#if BITS_PER_LONG == 64 29# define NBYTES(x) ((x) * 0x0101010101010101UL) 30# define NSIZE 8 31# define NSHIFT 3 32# define NSTRING "64" 33typedef u64 unative_t; 34#else 35# define NBYTES(x) ((x) * 0x01010101U) 36# define NSIZE 4 37# define NSHIFT 2 38# define NSTRING "32" 39typedef u32 unative_t; 40#endif 41 42 43 44/* 45 * These sub-operations are separate inlines since they can sometimes be 46 * specially optimized using architecture-specific hacks. 47 */ 48 49/* 50 * The SHLBYTE() operation shifts each byte left by 1, *not* 51 * rolling over into the next byte 52 */ 53static inline __attribute_const__ unative_t SHLBYTE(unative_t v) 54{ 55 unative_t vv; 56 57 vv = (v << 1) & NBYTES(0xfe); 58 return vv; 59} 60 61/* 62 * The MASK() operation returns 0xFF in any byte for which the high 63 * bit is 1, 0x00 for any byte for which the high bit is 0. 64 */ 65static inline __attribute_const__ unative_t MASK(unative_t v) 66{ 67 unative_t vv; 68 69 vv = v & NBYTES(0x80); 70 vv = (vv << 1) - (vv >> 7); /* Overflow on the top bit is OK */ 71 return vv; 72} 73 74 75static void raid6_int$#_gen_syndrome(int disks, size_t bytes, void **ptrs) 76{ 77 u8 **dptr = (u8 **)ptrs; 78 u8 *p, *q; 79 int d, z, z0; 80 81 unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 82 83 z0 = disks - 3; /* Highest data disk */ 84 p = dptr[z0+1]; /* XOR parity */ 85 q = dptr[z0+2]; /* RS syndrome */ 86 87 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 88 wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; 89 for ( z = z0-1 ; z >= 0 ; z-- ) { 90 wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE]; 91 wp$$ ^= wd$$; 92 w2$$ = MASK(wq$$); 93 w1$$ = SHLBYTE(wq$$); 94 w2$$ &= NBYTES(0x1d); 95 w1$$ ^= w2$$; 96 wq$$ = w1$$ ^ wd$$; 97 } 98 *(unative_t *)&p[d+NSIZE*$$] = wp$$; 99 *(unative_t *)&q[d+NSIZE*$$] = wq$$; 100 } 101} 102 103static void raid6_int$#_xor_syndrome(int disks, int start, int stop, 104 size_t bytes, void **ptrs) 105{ 106 u8 **dptr = (u8 **)ptrs; 107 u8 *p, *q; 108 int d, z, z0; 109 110 unative_t wd$$, wq$$, wp$$, w1$$, w2$$; 111 112 z0 = stop; /* P/Q right side optimization */ 113 p = dptr[disks-2]; /* XOR parity */ 114 q = dptr[disks-1]; /* RS syndrome */ 115 116 for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { 117 /* P/Q data pages */ 118 wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; 119 for ( z = z0-1 ; z >= start ; z-- ) { 120 wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE]; 121 wp$$ ^= wd$$; 122 w2$$ = MASK(wq$$); 123 w1$$ = SHLBYTE(wq$$); 124 w2$$ &= NBYTES(0x1d); 125 w1$$ ^= w2$$; 126 wq$$ = w1$$ ^ wd$$; 127 } 128 /* P/Q left side optimization */ 129 for ( z = start-1 ; z >= 0 ; z-- ) { 130 w2$$ = MASK(wq$$); 131 w1$$ = SHLBYTE(wq$$); 132 w2$$ &= NBYTES(0x1d); 133 wq$$ = w1$$ ^ w2$$; 134 } 135 *(unative_t *)&p[d+NSIZE*$$] ^= wp$$; 136 *(unative_t *)&q[d+NSIZE*$$] ^= wq$$; 137 } 138 139} 140 141const struct raid6_calls raid6_intx$# = { 142 raid6_int$#_gen_syndrome, 143 raid6_int$#_xor_syndrome, 144 NULL, /* always valid */ 145 "int" NSTRING "x$#", 146 0 147}; 148