void make_tables(void) { int i, j; uint8_t v; uint32_t b, log; /* Compute multiplication table */ for (i = 0; i < 256; i++) for (j = 0; j < 256; j++) raid6_gfmul[i][j] = gfmul(i, j); /* Compute power-of-2 table (exponent) */ v = 1; for (i = 0; i < 256; i++) { raid6_gfexp[i] = v; v = gfmul(v, 2); if (v == 1) v = 0; /* For entry 255, not a real entry */ } /* Compute inverse table x^-1 == x^254 */ for (i = 0; i < 256; i++) raid6_gfinv[i] = gfpow(i, 254); /* Compute inv(2^x + 1) (exponent-xor-inverse) table */ for (i = 0; i < 256; i ++) raid6_gfexi[i] = raid6_gfinv[raid6_gfexp[i] ^ 1]; /* Compute log and inverse log */ /* Modified code from: * http://web.eecs.utk.edu/~plank/plank/papers/CS-96-332.html */ b = 1; raid6_gflog[0] = 0; raid6_gfilog[255] = 0; for (log = 0; log < 255; log++) { raid6_gflog[b] = (uint8_t) log; raid6_gfilog[log] = (uint8_t) b; b = b << 1; if (b & 256) b = b ^ 0435; } tables_ready = 1; }
int main(int argc, char *argv[]) { int i, j, k; uint8_t v; uint8_t exptbl[256], invtbl[256]; printf("#include <linux/raid/pq.h>\n"); printf("#include <linux/export.h>\n"); 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,%c", gfmul(i, j + k), (k == 7) ? '\n' : ' '); } printf("\t},\n"); } printf("};\n"); printf("#ifdef __KERNEL__\n"); printf("EXPORT_SYMBOL(raid6_gfmul);\n"); printf("#endif\n"); 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,%c", v, (j == 7) ? '\n' : ' '); v = gfmul(v, 2); if (v == 1) v = 0; } } printf("};\n"); printf("#ifdef __KERNEL__\n"); printf("EXPORT_SYMBOL(raid6_gfexp);\n"); printf("#endif\n"); 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,%c", v, (j == 7) ? '\n' : ' '); } } printf("};\n"); printf("#ifdef __KERNEL__\n"); printf("EXPORT_SYMBOL(raid6_gfinv);\n"); printf("#endif\n"); 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,%c", invtbl[exptbl[i + j] ^ 1], (j == 7) ? '\n' : ' '); } printf("};\n"); printf("#ifdef __KERNEL__\n"); printf("EXPORT_SYMBOL(raid6_gfexi);\n"); printf("#endif\n"); return 0; }
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; }