Linux Audio

Check our new training course

Loading...
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* -*- linux-c -*- ------------------------------------------------------- *
  3 *
  4 *   Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
  5 *
 
 
 
 
  6 * ----------------------------------------------------------------------- */
  7
  8/*
  9 * mktables.c
 10 *
 11 * Make RAID-6 tables.  This is a host user space program to be run at
 12 * compile time.
 13 */
 14
 15#include <stdio.h>
 16#include <string.h>
 17#include <inttypes.h>
 18#include <stdlib.h>
 19#include <time.h>
 20
 21static uint8_t gfmul(uint8_t a, uint8_t b)
 22{
 23	uint8_t v = 0;
 24
 25	while (b) {
 26		if (b & 1)
 27			v ^= a;
 28		a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
 29		b >>= 1;
 30	}
 31
 32	return v;
 33}
 34
 35static uint8_t gfpow(uint8_t a, int b)
 36{
 37	uint8_t v = 1;
 38
 39	b %= 255;
 40	if (b < 0)
 41		b += 255;
 42
 43	while (b) {
 44		if (b & 1)
 45			v = gfmul(v, a);
 46		a = gfmul(a, a);
 47		b >>= 1;
 48	}
 49
 50	return v;
 51}
 52
 53int main(int argc, char *argv[])
 54{
 55	int i, j, k;
 56	uint8_t v;
 57	uint8_t exptbl[256], invtbl[256];
 58
 59	printf("#include <linux/export.h>\n");
 60	printf("#include <linux/raid/pq.h>\n");
 61
 62	/* Compute multiplication table */
 63	printf("\nconst u8  __attribute__((aligned(256)))\n"
 64		"raid6_gfmul[256][256] =\n"
 65		"{\n");
 66	for (i = 0; i < 256; i++) {
 67		printf("\t{\n");
 68		for (j = 0; j < 256; j += 8) {
 69			printf("\t\t");
 70			for (k = 0; k < 8; k++)
 71				printf("0x%02x,%c", gfmul(i, j + k),
 72				       (k == 7) ? '\n' : ' ');
 73		}
 74		printf("\t},\n");
 75	}
 76	printf("};\n");
 77	printf("#ifdef __KERNEL__\n");
 78	printf("EXPORT_SYMBOL(raid6_gfmul);\n");
 79	printf("#endif\n");
 80
 81	/* Compute vector multiplication table */
 82	printf("\nconst u8  __attribute__((aligned(256)))\n"
 83		"raid6_vgfmul[256][32] =\n"
 84		"{\n");
 85	for (i = 0; i < 256; i++) {
 86		printf("\t{\n");
 87		for (j = 0; j < 16; j += 8) {
 88			printf("\t\t");
 89			for (k = 0; k < 8; k++)
 90				printf("0x%02x,%c", gfmul(i, j + k),
 91				       (k == 7) ? '\n' : ' ');
 92		}
 93		for (j = 0; j < 16; j += 8) {
 94			printf("\t\t");
 95			for (k = 0; k < 8; k++)
 96				printf("0x%02x,%c", gfmul(i, (j + k) << 4),
 97				       (k == 7) ? '\n' : ' ');
 98		}
 99		printf("\t},\n");
100	}
101	printf("};\n");
102	printf("#ifdef __KERNEL__\n");
103	printf("EXPORT_SYMBOL(raid6_vgfmul);\n");
104	printf("#endif\n");
105
106	/* Compute power-of-2 table (exponent) */
107	v = 1;
108	printf("\nconst u8 __attribute__((aligned(256)))\n"
109	       "raid6_gfexp[256] =\n" "{\n");
110	for (i = 0; i < 256; i += 8) {
111		printf("\t");
112		for (j = 0; j < 8; j++) {
113			exptbl[i + j] = v;
114			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
115			v = gfmul(v, 2);
116			if (v == 1)
117				v = 0;	/* For entry 255, not a real entry */
118		}
119	}
120	printf("};\n");
121	printf("#ifdef __KERNEL__\n");
122	printf("EXPORT_SYMBOL(raid6_gfexp);\n");
123	printf("#endif\n");
124
125	/* Compute log-of-2 table */
126	printf("\nconst u8 __attribute__((aligned(256)))\n"
127	       "raid6_gflog[256] =\n" "{\n");
128	for (i = 0; i < 256; i += 8) {
129		printf("\t");
130		for (j = 0; j < 8; j++) {
131			v = 255;
132			for (k = 0; k < 256; k++)
133				if (exptbl[k] == (i + j)) {
134					v = k;
135					break;
136				}
137			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
138		}
139	}
140	printf("};\n");
141	printf("#ifdef __KERNEL__\n");
142	printf("EXPORT_SYMBOL(raid6_gflog);\n");
143	printf("#endif\n");
144
145	/* Compute inverse table x^-1 == x^254 */
146	printf("\nconst u8 __attribute__((aligned(256)))\n"
147	       "raid6_gfinv[256] =\n" "{\n");
148	for (i = 0; i < 256; i += 8) {
149		printf("\t");
150		for (j = 0; j < 8; j++) {
151			invtbl[i + j] = v = gfpow(i + j, 254);
152			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
153		}
154	}
155	printf("};\n");
156	printf("#ifdef __KERNEL__\n");
157	printf("EXPORT_SYMBOL(raid6_gfinv);\n");
158	printf("#endif\n");
159
160	/* Compute inv(2^x + 1) (exponent-xor-inverse) table */
161	printf("\nconst u8 __attribute__((aligned(256)))\n"
162	       "raid6_gfexi[256] =\n" "{\n");
163	for (i = 0; i < 256; i += 8) {
164		printf("\t");
165		for (j = 0; j < 8; j++)
166			printf("0x%02x,%c", invtbl[exptbl[i + j] ^ 1],
167			       (j == 7) ? '\n' : ' ');
168	}
169	printf("};\n");
170	printf("#ifdef __KERNEL__\n");
171	printf("EXPORT_SYMBOL(raid6_gfexi);\n");
172	printf("#endif\n");
173
174	return 0;
175}
v3.1
 
  1/* -*- linux-c -*- ------------------------------------------------------- *
  2 *
  3 *   Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
  4 *
  5 *   This file is part of the Linux kernel, and is made available under
  6 *   the terms of the GNU General Public License version 2 or (at your
  7 *   option) any later version; incorporated herein by reference.
  8 *
  9 * ----------------------------------------------------------------------- */
 10
 11/*
 12 * mktables.c
 13 *
 14 * Make RAID-6 tables.  This is a host user space program to be run at
 15 * compile time.
 16 */
 17
 18#include <stdio.h>
 19#include <string.h>
 20#include <inttypes.h>
 21#include <stdlib.h>
 22#include <time.h>
 23
 24static uint8_t gfmul(uint8_t a, uint8_t b)
 25{
 26	uint8_t v = 0;
 27
 28	while (b) {
 29		if (b & 1)
 30			v ^= a;
 31		a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
 32		b >>= 1;
 33	}
 34
 35	return v;
 36}
 37
 38static uint8_t gfpow(uint8_t a, int b)
 39{
 40	uint8_t v = 1;
 41
 42	b %= 255;
 43	if (b < 0)
 44		b += 255;
 45
 46	while (b) {
 47		if (b & 1)
 48			v = gfmul(v, a);
 49		a = gfmul(a, a);
 50		b >>= 1;
 51	}
 52
 53	return v;
 54}
 55
 56int main(int argc, char *argv[])
 57{
 58	int i, j, k;
 59	uint8_t v;
 60	uint8_t exptbl[256], invtbl[256];
 61
 
 62	printf("#include <linux/raid/pq.h>\n");
 63
 64	/* Compute multiplication table */
 65	printf("\nconst u8  __attribute__((aligned(256)))\n"
 66		"raid6_gfmul[256][256] =\n"
 67		"{\n");
 68	for (i = 0; i < 256; i++) {
 69		printf("\t{\n");
 70		for (j = 0; j < 256; j += 8) {
 71			printf("\t\t");
 72			for (k = 0; k < 8; k++)
 73				printf("0x%02x,%c", gfmul(i, j + k),
 74				       (k == 7) ? '\n' : ' ');
 75		}
 76		printf("\t},\n");
 77	}
 78	printf("};\n");
 79	printf("#ifdef __KERNEL__\n");
 80	printf("EXPORT_SYMBOL(raid6_gfmul);\n");
 81	printf("#endif\n");
 82
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 83	/* Compute power-of-2 table (exponent) */
 84	v = 1;
 85	printf("\nconst u8 __attribute__((aligned(256)))\n"
 86	       "raid6_gfexp[256] =\n" "{\n");
 87	for (i = 0; i < 256; i += 8) {
 88		printf("\t");
 89		for (j = 0; j < 8; j++) {
 90			exptbl[i + j] = v;
 91			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
 92			v = gfmul(v, 2);
 93			if (v == 1)
 94				v = 0;	/* For entry 255, not a real entry */
 95		}
 96	}
 97	printf("};\n");
 98	printf("#ifdef __KERNEL__\n");
 99	printf("EXPORT_SYMBOL(raid6_gfexp);\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
100	printf("#endif\n");
101
102	/* Compute inverse table x^-1 == x^254 */
103	printf("\nconst u8 __attribute__((aligned(256)))\n"
104	       "raid6_gfinv[256] =\n" "{\n");
105	for (i = 0; i < 256; i += 8) {
106		printf("\t");
107		for (j = 0; j < 8; j++) {
108			invtbl[i + j] = v = gfpow(i + j, 254);
109			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
110		}
111	}
112	printf("};\n");
113	printf("#ifdef __KERNEL__\n");
114	printf("EXPORT_SYMBOL(raid6_gfinv);\n");
115	printf("#endif\n");
116
117	/* Compute inv(2^x + 1) (exponent-xor-inverse) table */
118	printf("\nconst u8 __attribute__((aligned(256)))\n"
119	       "raid6_gfexi[256] =\n" "{\n");
120	for (i = 0; i < 256; i += 8) {
121		printf("\t");
122		for (j = 0; j < 8; j++)
123			printf("0x%02x,%c", invtbl[exptbl[i + j] ^ 1],
124			       (j == 7) ? '\n' : ' ');
125	}
126	printf("};\n");
127	printf("#ifdef __KERNEL__\n");
128	printf("EXPORT_SYMBOL(raid6_gfexi);\n");
129	printf("#endif\n");
130
131	return 0;
132}