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
  24 const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256)));
  25 struct raid6_calls raid6_call;
  26
  27 char *dataptrs[NDISKS];
  28 char data[NDISKS][PAGE_SIZE];
  29 char recovi[PAGE_SIZE], recovj[PAGE_SIZE];
  30
  31 static 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
  43 static 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
  55 static 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
  90 int 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 }