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(PAGE_SIZE))); 25 struct raid6_calls raid6_call; 26 27 char *dataptrs[NDISKS]; 28 char data[NDISKS][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); 29 char recovi[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); 30 char recovj[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); 31 32 static void makedata(int start, int stop) 33 { 34 int i, j; 35 36 for (i = start; i <= stop; i++) { 37 for (j = 0; j < PAGE_SIZE; j++) 38 data[i][j] = rand(); 39 40 dataptrs[i] = data[i]; 41 } 42 } 43 44 static char disk_type(int d) 45 { 46 switch (d) { 47 case NDISKS-2: 48 return 'P'; 49 case NDISKS-1: 50 return 'Q'; 51 default: 52 return 'D'; 53 } 54 } 55 56 static int test_disks(int i, int j) 57 { 58 int erra, errb; 59 60 memset(recovi, 0xf0, PAGE_SIZE); 61 memset(recovj, 0xba, PAGE_SIZE); 62 63 dataptrs[i] = recovi; 64 dataptrs[j] = recovj; 65 66 raid6_dual_recov(NDISKS, PAGE_SIZE, i, j, (void **)&dataptrs); 67 68 erra = memcmp(data[i], recovi, PAGE_SIZE); 69 errb = memcmp(data[j], recovj, PAGE_SIZE); 70 71 if (i < NDISKS-2 && j == NDISKS-1) { 72 /* We don't implement the DQ failure scenario, since it's 73 equivalent to a RAID-5 failure (XOR, then recompute Q) */ 74 erra = errb = 0; 75 } else { 76 printf("algo=%-8s faila=%3d(%c) failb=%3d(%c) %s\n", 77 raid6_call.name, 78 i, disk_type(i), 79 j, disk_type(j), 80 (!erra && !errb) ? "OK" : 81 !erra ? "ERRB" : 82 !errb ? "ERRA" : "ERRAB"); 83 } 84 85 dataptrs[i] = data[i]; 86 dataptrs[j] = data[j]; 87 88 return erra || errb; 89 } 90 91 int main(int argc, char *argv[]) 92 { 93 const struct raid6_calls *const *algo; 94 const struct raid6_recov_calls *const *ra; 95 int i, j, p1, p2; 96 int err = 0; 97 98 makedata(0, NDISKS-1); 99 100 for (ra = raid6_recov_algos; *ra; ra++) { 101 if ((*ra)->valid && !(*ra)->valid()) 102 continue; 103 104 raid6_2data_recov = (*ra)->data2; 105 raid6_datap_recov = (*ra)->datap; 106 107 printf("using recovery %s\n", (*ra)->name); 108 109 for (algo = raid6_algos; *algo; algo++) { 110 if ((*algo)->valid && !(*algo)->valid()) 111 continue; 112 113 raid6_call = **algo; 114 115 /* Nuke syndromes */ 116 memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE); 117 118 /* Generate assumed good syndrome */ 119 raid6_call.gen_syndrome(NDISKS, PAGE_SIZE, 120 (void **)&dataptrs); 121 122 for (i = 0; i < NDISKS-1; i++) 123 for (j = i+1; j < NDISKS; j++) 124 err += test_disks(i, j); 125 126 if (!raid6_call.xor_syndrome) 127 continue; 128 129 for (p1 = 0; p1 < NDISKS-2; p1++) 130 for (p2 = p1; p2 < NDISKS-2; p2++) { 131 132 /* Simulate rmw run */ 133 raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE, 134 (void **)&dataptrs); 135 makedata(p1, p2); 136 raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE, 137 (void **)&dataptrs); 138 139 for (i = 0; i < NDISKS-1; i++) 140 for (j = i+1; j < NDISKS; j++) 141 err += test_disks(i, j); 142 } 143 144 } 145 printf("\n"); 146 } 147 148 printf("\n"); 149 /* Pick the best algorithm test */ 150 raid6_select_algo(); 151 152 if (err) 153 printf("\n*** ERRORS FOUND ***\n"); 154 155 return err; 156 } 157