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/* -*- 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.
*
* ----------------------------------------------------------------------- */
/*
* raid6test.c
*
* Test RAID-6 recovery with various algorithms
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <linux/raid/pq.h>
#define NDISKS 16 /* Including P and Q */
const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
char *dataptrs[NDISKS];
char data[NDISKS][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
char recovi[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
char recovj[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
static void makedata(int start, int stop)
{
int i, j;
for (i = start; i <= stop; i++) {
for (j = 0; j < PAGE_SIZE; j++)
data[i][j] = rand();
dataptrs[i] = data[i];
}
}
static char disk_type(int d)
{
switch (d) {
case NDISKS-2:
return 'P';
case NDISKS-1:
return 'Q';
default:
return 'D';
}
}
static int test_disks(int i, int j)
{
int erra, errb;
memset(recovi, 0xf0, PAGE_SIZE);
memset(recovj, 0xba, PAGE_SIZE);
dataptrs[i] = recovi;
dataptrs[j] = recovj;
raid6_dual_recov(NDISKS, PAGE_SIZE, i, j, (void **)&dataptrs);
erra = memcmp(data[i], recovi, PAGE_SIZE);
errb = memcmp(data[j], recovj, PAGE_SIZE);
if (i < NDISKS-2 && j == NDISKS-1) {
/* We don't implement the DQ failure scenario, since it's
equivalent to a RAID-5 failure (XOR, then recompute Q) */
erra = errb = 0;
} else {
printf("algo=%-8s faila=%3d(%c) failb=%3d(%c) %s\n",
raid6_call.name,
i, disk_type(i),
j, disk_type(j),
(!erra && !errb) ? "OK" :
!erra ? "ERRB" :
!errb ? "ERRA" : "ERRAB");
}
dataptrs[i] = data[i];
dataptrs[j] = data[j];
return erra || errb;
}
int main(int argc, char *argv[])
{
const struct raid6_calls *const *algo;
const struct raid6_recov_calls *const *ra;
int i, j, p1, p2;
int err = 0;
makedata(0, NDISKS-1);
for (ra = raid6_recov_algos; *ra; ra++) {
if ((*ra)->valid && !(*ra)->valid())
continue;
raid6_2data_recov = (*ra)->data2;
raid6_datap_recov = (*ra)->datap;
printf("using recovery %s\n", (*ra)->name);
for (algo = raid6_algos; *algo; algo++) {
if ((*algo)->valid && !(*algo)->valid())
continue;
raid6_call = **algo;
/* Nuke syndromes */
memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
/* Generate assumed good syndrome */
raid6_call.gen_syndrome(NDISKS, PAGE_SIZE,
(void **)&dataptrs);
for (i = 0; i < NDISKS-1; i++)
for (j = i+1; j < NDISKS; j++)
err += test_disks(i, j);
if (!raid6_call.xor_syndrome)
continue;
for (p1 = 0; p1 < NDISKS-2; p1++)
for (p2 = p1; p2 < NDISKS-2; p2++) {
/* Simulate rmw run */
raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
(void **)&dataptrs);
makedata(p1, p2);
raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
(void **)&dataptrs);
for (i = 0; i < NDISKS-1; i++)
for (j = i+1; j < NDISKS; j++)
err += test_disks(i, j);
}
}
printf("\n");
}
printf("\n");
/* Pick the best algorithm test */
raid6_select_algo();
if (err)
printf("\n*** ERRORS FOUND ***\n");
return err;
}
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