1// SPDX-License-Identifier: GPL-2.0-or-later
2/* -*- linux-c -*- ------------------------------------------------------- *
3 *
4 * Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
5 *
6 * ----------------------------------------------------------------------- */
7
8/*
9 * raid6test.c
10 *
11 * Test RAID-6 recovery with various algorithms
12 */
13
14#include <stdlib.h>
15#include <stdio.h>
16#include <string.h>
17#include <linux/raid/pq.h>
18
19#define NDISKS 16 /* Including P and Q */
20
21const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
22
23char *dataptrs[NDISKS];
24char data[NDISKS][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
25char recovi[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
26char recovj[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
27
28static void makedata(int start, int stop)
29{
30 int i, j;
31
32 for (i = start; i <= stop; i++) {
33 for (j = 0; j < PAGE_SIZE; j++)
34 data[i][j] = rand();
35
36 dataptrs[i] = data[i];
37 }
38}
39
40static char disk_type(int d)
41{
42 switch (d) {
43 case NDISKS-2:
44 return 'P';
45 case NDISKS-1:
46 return 'Q';
47 default:
48 return 'D';
49 }
50}
51
52static int test_disks(int i, int j)
53{
54 int erra, errb;
55
56 memset(recovi, 0xf0, PAGE_SIZE);
57 memset(recovj, 0xba, PAGE_SIZE);
58
59 dataptrs[i] = recovi;
60 dataptrs[j] = recovj;
61
62 raid6_dual_recov(NDISKS, PAGE_SIZE, faila: i, failb: j, ptrs: (void **)&dataptrs);
63
64 erra = memcmp(p: data[i], q: recovi, PAGE_SIZE);
65 errb = memcmp(p: data[j], q: recovj, PAGE_SIZE);
66
67 if (i < NDISKS-2 && j == NDISKS-1) {
68 /* We don't implement the DQ failure scenario, since it's
69 equivalent to a RAID-5 failure (XOR, then recompute Q) */
70 erra = errb = 0;
71 } else {
72 printf("algo=%-8s faila=%3d(%c) failb=%3d(%c) %s\n",
73 raid6_call.name,
74 i, disk_type(i),
75 j, disk_type(j),
76 (!erra && !errb) ? "OK" :
77 !erra ? "ERRB" :
78 !errb ? "ERRA" : "ERRAB");
79 }
80
81 dataptrs[i] = data[i];
82 dataptrs[j] = data[j];
83
84 return erra || errb;
85}
86
87int main(int argc, char *argv[])
88{
89 const struct raid6_calls *const *algo;
90 const struct raid6_recov_calls *const *ra;
91 int i, j, p1, p2;
92 int err = 0;
93
94 makedata(start: 0, NDISKS-1);
95
96 for (ra = raid6_recov_algos; *ra; ra++) {
97 if ((*ra)->valid && !(*ra)->valid())
98 continue;
99
100 raid6_2data_recov = (*ra)->data2;
101 raid6_datap_recov = (*ra)->datap;
102
103 printf("using recovery %s\n", (*ra)->name);
104
105 for (algo = raid6_algos; *algo; algo++) {
106 if ((*algo)->valid && !(*algo)->valid())
107 continue;
108
109 raid6_call = **algo;
110
111 /* Nuke syndromes */
112 memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
113
114 /* Generate assumed good syndrome */
115 raid6_call.gen_syndrome(NDISKS, PAGE_SIZE,
116 (void **)&dataptrs);
117
118 for (i = 0; i < NDISKS-1; i++)
119 for (j = i+1; j < NDISKS; j++)
120 err += test_disks(i, j);
121
122 if (!raid6_call.xor_syndrome)
123 continue;
124
125 for (p1 = 0; p1 < NDISKS-2; p1++)
126 for (p2 = p1; p2 < NDISKS-2; p2++) {
127
128 /* Simulate rmw run */
129 raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
130 (void **)&dataptrs);
131 makedata(start: p1, stop: p2);
132 raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
133 (void **)&dataptrs);
134
135 for (i = 0; i < NDISKS-1; i++)
136 for (j = i+1; j < NDISKS; j++)
137 err += test_disks(i, j);
138 }
139
140 }
141 printf("\n");
142 }
143
144 printf("\n");
145 /* Pick the best algorithm test */
146 raid6_select_algo();
147
148 if (err)
149 printf("\n*** ERRORS FOUND ***\n");
150
151 return err;
152}
153

source code of linux/lib/raid6/test/test.c