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	const struct raid6_recov_calls *const *ra;
94	int i, j;
95	int err = 0;
96
97	makedata();
98
99	for (ra = raid6_recov_algos; *ra; ra++) {
100		if ((*ra)->valid  && !(*ra)->valid())
101			continue;
102		raid6_2data_recov = (*ra)->data2;
103		raid6_datap_recov = (*ra)->datap;
104
105		printf("using recovery %s\n", (*ra)->name);
106
107		for (algo = raid6_algos; *algo; algo++) {
108			if (!(*algo)->valid || (*algo)->valid()) {
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		}
123		printf("\n");
124	}
125
126	printf("\n");
127	/* Pick the best algorithm test */
128	raid6_select_algo();
129
130	if (err)
131		printf("\n*** ERRORS FOUND ***\n");
132
133	return err;
134}
135