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(int start, int stop)
32{
33	int i, j;
34
35	for (i = start; i <= stop; 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, p1, p2;
95	int err = 0;
96
97	makedata(0, NDISKS-1);
98
99	for (ra = raid6_recov_algos; *ra; ra++) {
100		if ((*ra)->valid  && !(*ra)->valid())
101			continue;
102
103		raid6_2data_recov = (*ra)->data2;
104		raid6_datap_recov = (*ra)->datap;
105
106		printf("using recovery %s\n", (*ra)->name);
107
108		for (algo = raid6_algos; *algo; algo++) {
109			if ((*algo)->valid && !(*algo)->valid())
110				continue;
111
112			raid6_call = **algo;
113
114			/* Nuke syndromes */
115			memset(data[NDISKS-2], 0xee, 2*PAGE_SIZE);
116
117			/* Generate assumed good syndrome */
118			raid6_call.gen_syndrome(NDISKS, PAGE_SIZE,
119						(void **)&dataptrs);
120
121			for (i = 0; i < NDISKS-1; i++)
122				for (j = i+1; j < NDISKS; j++)
123					err += test_disks(i, j);
124
125			if (!raid6_call.xor_syndrome)
126				continue;
127
128			for (p1 = 0; p1 < NDISKS-2; p1++)
129				for (p2 = p1; p2 < NDISKS-2; p2++) {
130
131					/* Simulate rmw run */
132					raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
133								(void **)&dataptrs);
134					makedata(p1, p2);
135					raid6_call.xor_syndrome(NDISKS, p1, p2, PAGE_SIZE,
136                                                                (void **)&dataptrs);
137
138					for (i = 0; i < NDISKS-1; i++)
139						for (j = i+1; j < NDISKS; j++)
140							err += test_disks(i, j);
141				}
142
143		}
144		printf("\n");
145	}
146
147	printf("\n");
148	/* Pick the best algorithm test */
149	raid6_select_algo();
150
151	if (err)
152		printf("\n*** ERRORS FOUND ***\n");
153
154	return err;
155}
156