diff options
Diffstat (limited to 'drivers/md/mktables.c')
| -rw-r--r-- | drivers/md/mktables.c | 180 |
1 files changed, 92 insertions, 88 deletions
diff --git a/drivers/md/mktables.c b/drivers/md/mktables.c index adef299908c..339afd0e1b1 100644 --- a/drivers/md/mktables.c +++ b/drivers/md/mktables.c @@ -26,100 +26,104 @@ static uint8_t gfmul(uint8_t a, uint8_t b) { - uint8_t v = 0; - - while ( b ) { - if ( b & 1 ) v ^= a; - a = (a << 1) ^ (a & 0x80 ? 0x1d : 0); - b >>= 1; - } - return v; + uint8_t v = 0; + + while (b) { + if (b & 1) + v ^= a; + a = (a << 1) ^ (a & 0x80 ? 0x1d : 0); + b >>= 1; + } + + return v; } static uint8_t gfpow(uint8_t a, int b) { - uint8_t v = 1; - - b %= 255; - if ( b < 0 ) - b += 255; - - while ( b ) { - if ( b & 1 ) v = gfmul(v,a); - a = gfmul(a,a); - b >>= 1; - } - return v; + uint8_t v = 1; + + b %= 255; + if (b < 0) + b += 255; + + while (b) { + if (b & 1) + v = gfmul(v, a); + a = gfmul(a, a); + b >>= 1; + } + + return v; } int main(int argc, char *argv[]) { - int i, j, k; - uint8_t v; - uint8_t exptbl[256], invtbl[256]; - - printf("#include \"raid6.h\"\n"); - - /* Compute multiplication table */ - printf("\nconst u8 __attribute__((aligned(256)))\n" - "raid6_gfmul[256][256] =\n" - "{\n"); - for ( i = 0 ; i < 256 ; i++ ) { - printf("\t{\n"); - for ( j = 0 ; j < 256 ; j += 8 ) { - printf("\t\t"); - for ( k = 0 ; k < 8 ; k++ ) { - printf("0x%02x, ", gfmul(i,j+k)); - } - printf("\n"); - } - printf("\t},\n"); - } - printf("};\n"); - - /* Compute power-of-2 table (exponent) */ - v = 1; - printf("\nconst u8 __attribute__((aligned(256)))\n" - "raid6_gfexp[256] =\n" - "{\n"); - for ( i = 0 ; i < 256 ; i += 8 ) { - printf("\t"); - for ( j = 0 ; j < 8 ; j++ ) { - exptbl[i+j] = v; - printf("0x%02x, ", v); - v = gfmul(v,2); - if ( v == 1 ) v = 0; /* For entry 255, not a real entry */ - } - printf("\n"); - } - printf("};\n"); - - /* Compute inverse table x^-1 == x^254 */ - printf("\nconst u8 __attribute__((aligned(256)))\n" - "raid6_gfinv[256] =\n" - "{\n"); - for ( i = 0 ; i < 256 ; i += 8 ) { - printf("\t"); - for ( j = 0 ; j < 8 ; j++ ) { - invtbl[i+j] = v = gfpow(i+j,254); - printf("0x%02x, ", v); - } - printf("\n"); - } - printf("};\n"); - - /* Compute inv(2^x + 1) (exponent-xor-inverse) table */ - printf("\nconst u8 __attribute__((aligned(256)))\n" - "raid6_gfexi[256] =\n" - "{\n"); - for ( i = 0 ; i < 256 ; i += 8 ) { - printf("\t"); - for ( j = 0 ; j < 8 ; j++ ) { - printf("0x%02x, ", invtbl[exptbl[i+j]^1]); - } - printf("\n"); - } - printf("};\n\n"); - - return 0; + int i, j, k; + uint8_t v; + uint8_t exptbl[256], invtbl[256]; + + printf("#include \"raid6.h\"\n"); + + /* Compute multiplication table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfmul[256][256] =\n" + "{\n"); + for (i = 0; i < 256; i++) { + printf("\t{\n"); + for (j = 0; j < 256; j += 8) { + printf("\t\t"); + for (k = 0; k < 8; k++) + printf("0x%02x, ", gfmul(i, j+k)); + printf("\n"); + } + printf("\t},\n"); + } + printf("};\n"); + + /* Compute power-of-2 table (exponent) */ + v = 1; + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfexp[256] =\n" + "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + exptbl[i+j] = v; + printf("0x%02x, ", v); + v = gfmul(v, 2); + if (v == 1) + v = 0; /* For entry 255, not a real entry */ + } + printf("\n"); + } + printf("};\n"); + + /* Compute inverse table x^-1 == x^254 */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfinv[256] =\n" + "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + v = gfpow(i+j, 254); + invtbl[i+j] = v; + printf("0x%02x, ", v); + } + printf("\n"); + } + printf("};\n"); + + /* Compute inv(2^x + 1) (exponent-xor-inverse) table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfexi[256] =\n" + "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) + printf("0x%02x, ", invtbl[exptbl[i+j]^1]); + printf("\n"); + } + printf("};\n\n"); + + return 0; } |