LXR linux/drivers/md/raid6test/test.c

   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 * raid6test.c
  13 *
  14 * Test RAID-6 recovery with various algorithms
  15 */
  16
  17#include <stdlib.h>
  18#include <stdio.h>
  19#include <string.h>
  20#include <linux/raid/pq.h>
  21
  22#define NDISKS          16      /* Including P and Q */
  23
  24const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
  25struct raid6_calls raid6_call;
  26
  27char *dataptrs[NDISKS];
  28char data[NDISKS][PAGE_SIZE];
  29char recovi[PAGE_SIZE], recovj[PAGE_SIZE];
  30
  31static void makedata(void)
  32{
  33        int i, j;
  34
  35        for (i = 0; i < NDISKS; i++) {
  36                for (j = 0; j < PAGE_SIZE; j++)
  37                        data[i][j] = rand();
  38
  39                dataptrs[i] = data[i];
  40        }
  41}
  42
  43static char disk_type(int d)
  44{
  45        switch (d) {
  46        case NDISKS-2:
  47                return 'P';
  48        case NDISKS-1:
  49                return 'Q';
  50        default:
  51                return 'D';
  52        }
  53}
  54
  55static int test_disks(int i, int j)
  56{
  57        int erra, errb;
  58
  59        memset(recovi, 0xf0, PAGE_SIZE);
  60        memset(recovj, 0xba, PAGE_SIZE);
  61
  62        dataptrs[i] = recovi;
  63        dataptrs[j] = recovj;
  64
  65        raid6_dual_recov(NDISKS, PAGE_SIZE, i, j, (void **)&dataptrs);
  66
  67        erra = memcmp(data[i], recovi, PAGE_SIZE);
  68        errb = memcmp(data[j], recovj, PAGE_SIZE);
  69
  70        if (i < NDISKS-2 && j == NDISKS-1) {
  71                /* We don't implement the DQ failure scenario, since it's
  72                   equivalent to a RAID-5 failure (XOR, then recompute Q) */
  73                erra = errb = 0;
  74        } else {
  75                printf("algo=%-8s  faila=%3d(%c)  failb=%3d(%c)  %s\n",
  76                       raid6_call.name,
  77                       i, disk_type(i),
  78                       j, disk_type(j),
  79                       (!erra && !errb) ? "OK" :
  80                       !erra ? "ERRB" :
  81                       !errb ? "ERRA" : "ERRAB");
  82        }
  83
  84        dataptrs[i] = data[i];
  85        dataptrs[j] = data[j];
  86
  87        return erra || errb;
  88}
  89
  90int main(int argc, char *argv[])
  91{
  92        const struct raid6_calls *const *algo;
  93        int i, j;
  94        int err = 0;
  95
  96        makedata();
  97
  98        for (algo = raid6_algos; *algo; algo++) {
  99                if (!(*algo)->valid || (*algo)->valid()) {
 100                        raid6_call = **algo;
 101
 102                        /* Nuke syndromes */
 103                        memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
 104
 105                        /* Generate assumed good syndrome */
 106                        raid6_call.gen_syndrome(NDISKS, PAGE_SIZE,
 107                                                (void **)&dataptrs);
 108
 109                        for (i = 0; i < NDISKS-1; i++)
 110                                for (j = i+1; j < NDISKS; j++)
 111                                        err += test_disks(i, j);
 112                }
 113                printf("\n");
 114        }
 115
 116        printf("\n");
 117        /* Pick the best algorithm test */
 118        raid6_select_algo();
 119
 120        if (err)
 121                printf("\n*** ERRORS FOUND ***\n");
 122
 123        return err;
 124}
 125