1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -*- linux-c -*- ------------------------------------------------------- *
4  *   Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
6  * ----------------------------------------------------------------------- */
11  * Make RAID-6 tables.  This is a host user space program to be run at
55 	int i, j, k;  in main()  local
68 		for (j = 0; j < 256; j += 8) {  in main()
70 			for (k = 0; k < 8; k++)  in main()
71 				printf("0x%02x,%c", gfmul(i, j + k),  in main()
72 				       (k == 7) ? '\n' : ' ');  in main()
87 		for (j = 0; j < 16; j += 8) {  in main()
89 			for (k = 0; k < 8; k++)  in main()
90 				printf("0x%02x,%c", gfmul(i, j + k),  in main()
91 				       (k == 7) ? '\n' : ' ');  in main()
93 		for (j = 0; j < 16; j += 8) {  in main()
95 			for (k = 0; k < 8; k++)  in main()
96 				printf("0x%02x,%c", gfmul(i, (j + k) << 4),  in main()
97 				       (k == 7) ? '\n' : ' ');  in main()
106 	/* Compute power-of-2 table (exponent) */  in main()
112 		for (j = 0; j < 8; j++) {  in main()
113 			exptbl[i + j] = v;  in main()
114 			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');  in main()
125 	/* Compute log-of-2 table */  in main()
130 		for (j = 0; j < 8; j++) {  in main()
132 			for (k = 0; k < 256; k++)  in main()
133 				if (exptbl[k] == (i + j)) {  in main()
134 					v = k;  in main()
137 			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');  in main()
145 	/* Compute inverse table x^-1 == x^254 */  in main()
150 		for (j = 0; j < 8; j++) {  in main()
151 			invtbl[i + j] = v = gfpow(i + j, 254);  in main()
152 			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');  in main()
160 	/* Compute inv(2^x + 1) (exponent-xor-inverse) table */  in main()
165 		for (j = 0; j < 8; j++)  in main()
166 			printf("0x%02x,%c", invtbl[exptbl[i + j] ^ 1],  in main()
167 			       (j == 7) ? '\n' : ' ');  in main()