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authorDavid Woodhouse <dwmw2@tylersburg.infradead.org>2009-07-13 11:35:12 +0100
committerDavid Woodhouse <David.Woodhouse@intel.com>2009-10-29 14:38:47 +0000
commitf5e70d0fe3ea990cfb3fc8d7f76a719adcb1e0b5 (patch)
tree1794eb51814228ff76f672a541100ad62dd791c9 /drivers/md/mktables.c
parent17d857be649a21ca90008c6dc425d849fa83db5c (diff)
downloadop-kernel-dev-f5e70d0fe3ea990cfb3fc8d7f76a719adcb1e0b5.zip
op-kernel-dev-f5e70d0fe3ea990cfb3fc8d7f76a719adcb1e0b5.tar.gz
md: Factor out RAID6 algorithms into lib/
We'll want to use these in btrfs too. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/md/mktables.c')
-rw-r--r--drivers/md/mktables.c132
1 files changed, 0 insertions, 132 deletions
diff --git a/drivers/md/mktables.c b/drivers/md/mktables.c
deleted file mode 100644
index 3b15008..0000000
--- a/drivers/md/mktables.c
+++ /dev/null
@@ -1,132 +0,0 @@
-/* -*- linux-c -*- ------------------------------------------------------- *
- *
- * Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
- *
- * This file is part of the Linux kernel, and is made available under
- * the terms of the GNU General Public License version 2 or (at your
- * option) any later version; incorporated herein by reference.
- *
- * ----------------------------------------------------------------------- */
-
-/*
- * mktables.c
- *
- * Make RAID-6 tables. This is a host user space program to be run at
- * compile time.
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <inttypes.h>
-#include <stdlib.h>
-#include <time.h>
-
-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;
-}
-
-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;
-}
-
-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");
-
- /* 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,%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");
-
- /* 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,%c", v, (j == 7) ? '\n' : ' ');
- v = gfmul(v, 2);
- if (v == 1)
- v = 0; /* For entry 255, not a real entry */
- }
- }
- printf("};\n");
- printf("#ifdef __KERNEL__\n");
- printf("EXPORT_SYMBOL(raid6_gfexp);\n");
- printf("#endif\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,%c", v, (j == 7) ? '\n' : ' ');
- }
- }
- printf("};\n");
- printf("#ifdef __KERNEL__\n");
- printf("EXPORT_SYMBOL(raid6_gfinv);\n");
- printf("#endif\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,%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;
-}
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