1 /*
2 * asynchronous raid6 recovery self test
3 * Copyright (c) 2009, Intel Corporation.
4 *
5 * based on drivers/md/raid6test/test.c:
6 * Copyright 2002-2007 H. Peter Anvin
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 */
22 #include <linux/async_tx.h>
23 #include <linux/gfp.h>
24 #include <linux/mm.h>
25 #include <linux/random.h>
26 #include <linux/module.h>
27
28 #undef pr
29 #define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
30
31 #define NDISKS 16 /* Including P and Q */
32
33 static struct page *dataptrs[NDISKS];
34 static addr_conv_t addr_conv[NDISKS];
35 static struct page *data[NDISKS+3];
36 static struct page *spare;
37 static struct page *recovi;
38 static struct page *recovj;
39
callback(void * param)40 static void callback(void *param)
41 {
42 struct completion *cmp = param;
43
44 complete(cmp);
45 }
46
makedata(int disks)47 static void makedata(int disks)
48 {
49 int i;
50
51 for (i = 0; i < disks; i++) {
52 prandom_bytes(page_address(data[i]), PAGE_SIZE);
53 dataptrs[i] = data[i];
54 }
55 }
56
disk_type(int d,int disks)57 static char disk_type(int d, int disks)
58 {
59 if (d == disks - 2)
60 return 'P';
61 else if (d == disks - 1)
62 return 'Q';
63 else
64 return 'D';
65 }
66
67 /* Recover two failed blocks. */
raid6_dual_recov(int disks,size_t bytes,int faila,int failb,struct page ** ptrs)68 static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs)
69 {
70 struct async_submit_ctl submit;
71 struct completion cmp;
72 struct dma_async_tx_descriptor *tx = NULL;
73 enum sum_check_flags result = ~0;
74
75 if (faila > failb)
76 swap(faila, failb);
77
78 if (failb == disks-1) {
79 if (faila == disks-2) {
80 /* P+Q failure. Just rebuild the syndrome. */
81 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
82 tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
83 } else {
84 struct page *blocks[disks];
85 struct page *dest;
86 int count = 0;
87 int i;
88
89 /* data+Q failure. Reconstruct data from P,
90 * then rebuild syndrome
91 */
92 for (i = disks; i-- ; ) {
93 if (i == faila || i == failb)
94 continue;
95 blocks[count++] = ptrs[i];
96 }
97 dest = ptrs[faila];
98 init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
99 NULL, NULL, addr_conv);
100 tx = async_xor(dest, blocks, 0, count, bytes, &submit);
101
102 init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);
103 tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
104 }
105 } else {
106 if (failb == disks-2) {
107 /* data+P failure. */
108 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
109 tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit);
110 } else {
111 /* data+data failure. */
112 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
113 tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit);
114 }
115 }
116 init_completion(&cmp);
117 init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);
118 tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit);
119 async_tx_issue_pending(tx);
120
121 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)
122 pr("%s: timeout! (faila: %d failb: %d disks: %d)\n",
123 __func__, faila, failb, disks);
124
125 if (result != 0)
126 pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n",
127 __func__, faila, failb, result);
128 }
129
test_disks(int i,int j,int disks)130 static int test_disks(int i, int j, int disks)
131 {
132 int erra, errb;
133
134 memset(page_address(recovi), 0xf0, PAGE_SIZE);
135 memset(page_address(recovj), 0xba, PAGE_SIZE);
136
137 dataptrs[i] = recovi;
138 dataptrs[j] = recovj;
139
140 raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs);
141
142 erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);
143 errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE);
144
145 pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n",
146 __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks),
147 (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB");
148
149 dataptrs[i] = data[i];
150 dataptrs[j] = data[j];
151
152 return erra || errb;
153 }
154
test(int disks,int * tests)155 static int test(int disks, int *tests)
156 {
157 struct dma_async_tx_descriptor *tx;
158 struct async_submit_ctl submit;
159 struct completion cmp;
160 int err = 0;
161 int i, j;
162
163 recovi = data[disks];
164 recovj = data[disks+1];
165 spare = data[disks+2];
166
167 makedata(disks);
168
169 /* Nuke syndromes */
170 memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);
171 memset(page_address(data[disks-1]), 0xee, PAGE_SIZE);
172
173 /* Generate assumed good syndrome */
174 init_completion(&cmp);
175 init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
176 tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit);
177 async_tx_issue_pending(tx);
178
179 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {
180 pr("error: initial gen_syndrome(%d) timed out\n", disks);
181 return 1;
182 }
183
184 pr("testing the %d-disk case...\n", disks);
185 for (i = 0; i < disks-1; i++)
186 for (j = i+1; j < disks; j++) {
187 (*tests)++;
188 err += test_disks(i, j, disks);
189 }
190
191 return err;
192 }
193
194
raid6_test(void)195 static int raid6_test(void)
196 {
197 int err = 0;
198 int tests = 0;
199 int i;
200
201 for (i = 0; i < NDISKS+3; i++) {
202 data[i] = alloc_page(GFP_KERNEL);
203 if (!data[i]) {
204 while (i--)
205 put_page(data[i]);
206 return -ENOMEM;
207 }
208 }
209
210 /* the 4-disk and 5-disk cases are special for the recovery code */
211 if (NDISKS > 4)
212 err += test(4, &tests);
213 if (NDISKS > 5)
214 err += test(5, &tests);
215 /* the 11 and 12 disk cases are special for ioatdma (p-disabled
216 * q-continuation without extended descriptor)
217 */
218 if (NDISKS > 12) {
219 err += test(11, &tests);
220 err += test(12, &tests);
221 }
222 err += test(NDISKS, &tests);
223
224 pr("\n");
225 pr("complete (%d tests, %d failure%s)\n",
226 tests, err, err == 1 ? "" : "s");
227
228 for (i = 0; i < NDISKS+3; i++)
229 put_page(data[i]);
230
231 return 0;
232 }
233
raid6_test_exit(void)234 static void raid6_test_exit(void)
235 {
236 }
237
238 /* when compiled-in wait for drivers to load first (assumes dma drivers
239 * are also compliled-in)
240 */
241 late_initcall(raid6_test);
242 module_exit(raid6_test_exit);
243 MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
244 MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");
245 MODULE_LICENSE("GPL");
246