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1/* -*- linux-c -*- ------------------------------------------------------- *2 *3 * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved4 *5 * This program is free software; you can redistribute it and/or modify6 * it under the terms of the GNU General Public License as published by7 * the Free Software Foundation, Inc., 53 Temple Place Ste 330,8 * Boston MA 02111-1307, USA; either version 2 of the License, or9 * (at your option) any later version; incorporated herein by reference.10 *11 * ----------------------------------------------------------------------- */12 13/*14 * int$#.c15 *16 * $#-way unrolled portable integer math RAID-6 instruction set17 *18 * This file is postprocessed using unroll.awk19 */20 21#include <linux/raid/pq.h>22 23/*24 * This is the C data type to use25 */26 27/* Change this from BITS_PER_LONG if there is something better... */28#if BITS_PER_LONG == 6429# define NBYTES(x) ((x) * 0x0101010101010101UL)30# define NSIZE 831# define NSHIFT 332# define NSTRING "64"33typedef u64 unative_t;34#else35# define NBYTES(x) ((x) * 0x01010101U)36# define NSIZE 437# define NSHIFT 238# define NSTRING "32"39typedef u32 unative_t;40#endif41 42 43 44/*45 * These sub-operations are separate inlines since they can sometimes be46 * specially optimized using architecture-specific hacks.47 */48 49/*50 * The SHLBYTE() operation shifts each byte left by 1, *not*51 * rolling over into the next byte52 */53static inline __attribute_const__ unative_t SHLBYTE(unative_t v)54{55 unative_t vv;56 57 vv = (v << 1) & NBYTES(0xfe);58 return vv;59}60 61/*62 * The MASK() operation returns 0xFF in any byte for which the high63 * bit is 1, 0x00 for any byte for which the high bit is 0.64 */65static inline __attribute_const__ unative_t MASK(unative_t v)66{67 unative_t vv;68 69 vv = v & NBYTES(0x80);70 vv = (vv << 1) - (vv >> 7); /* Overflow on the top bit is OK */71 return vv;72}73 74 75static void raid6_int$#_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 0147};148