1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * asynchronous raid6 recovery self test
4 * Copyright (c) 2009, Intel Corporation.
5 *
6 * based on drivers/md/raid6test/test.c:
7 * Copyright 2002-2007 H. Peter Anvin
8 */
9 #include <linux/async_tx.h>
10 #include <linux/gfp.h>
11 #include <linux/mm.h>
12 #include <linux/random.h>
13 #include <linux/module.h>
14
15 #undef pr
16 #define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
17
18 #define NDISKS 64 /* Including P and Q */
19
20 static struct page *dataptrs[NDISKS];
21 unsigned int dataoffs[NDISKS];
22 static addr_conv_t addr_conv[NDISKS];
23 static struct page *data[NDISKS+3];
24 static struct page *spare;
25 static struct page *recovi;
26 static struct page *recovj;
27
28 static void callback(void *param)
29 {
30 struct completion *cmp = param;
31
32 complete(cmp);
33 }
34
35 static void makedata(int disks)
36 {
37 int i;
38
39 for (i = 0; i < disks; i++) {
40 get_random_bytes(page_address(data[i]), PAGE_SIZE);
41 dataptrs[i] = data[i];
42 dataoffs[i] = 0;
43 }
44 }
45
46 static char disk_type(int d, int disks)
47 {
48 if (d == disks - 2)
49 return 'P';
50 else if (d == disks - 1)
51 return 'Q';
52 else
53 return 'D';
54 }
55
56 /* Recover two failed blocks. */
57 static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb,
58 struct page **ptrs, unsigned int *offs)
59 {
60 struct async_submit_ctl submit;
61 struct completion cmp;
62 struct dma_async_tx_descriptor *tx = NULL;
63 enum sum_check_flags result = ~0;
64
65 if (faila > failb)
66 swap(faila, failb);
67
68 if (failb == disks-1) {
69 if (faila == disks-2) {
70 /* P+Q failure. Just rebuild the syndrome. */
71 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
72 tx = async_gen_syndrome(ptrs, offs,
73 disks, bytes, &submit);
74 } else {
75 struct page *blocks[NDISKS];
76 struct page *dest;
77 int count = 0;
78 int i;
79
80 BUG_ON(disks > NDISKS);
81
82 /* data+Q failure. Reconstruct data from P,
83 * then rebuild syndrome
84 */
85 for (i = disks; i-- ; ) {
86 if (i == faila || i == failb)
87 continue;
88 blocks[count++] = ptrs[i];
89 }
90 dest = ptrs[faila];
91 init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
92 NULL, NULL, addr_conv);
93 tx = async_xor(dest, blocks, 0, count, bytes, &submit);
94
95 init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);
96 tx = async_gen_syndrome(ptrs, offs,
97 disks, bytes, &submit);
98 }
99 } else {
100 if (failb == disks-2) {
101 /* data+P failure. */
102 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
103 tx = async_raid6_datap_recov(disks, bytes,
104 faila, ptrs, offs, &submit);
105 } else {
106 /* data+data failure. */
107 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
108 tx = async_raid6_2data_recov(disks, bytes,
109 faila, failb, ptrs, offs, &submit);
110 }
111 }
112 init_completion(&cmp);
113 init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);
114 tx = async_syndrome_val(ptrs, offs,
115 disks, bytes, &result, spare, 0, &submit);
116 async_tx_issue_pending(tx);
117
118 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)
119 pr("%s: timeout! (faila: %d failb: %d disks: %d)\n",
120 __func__, faila, failb, disks);
121
122 if (result != 0)
123 pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n",
124 __func__, faila, failb, result);
125 }
126
127 static int test_disks(int i, int j, int disks)
128 {
129 int erra, errb;
130
131 memset(page_address(recovi), 0xf0, PAGE_SIZE);
132 memset(page_address(recovj), 0xba, PAGE_SIZE);
133
134 dataptrs[i] = recovi;
135 dataptrs[j] = recovj;
136
137 raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs, dataoffs);
138
139 erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);
140 errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE);
141
142 pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n",
143 __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks),
144 (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB");
145
146 dataptrs[i] = data[i];
147 dataptrs[j] = data[j];
148
149 return erra || errb;
150 }
151
152 static int test(int disks, int *tests)
153 {
154 struct dma_async_tx_descriptor *tx;
155 struct async_submit_ctl submit;
156 struct completion cmp;
157 int err = 0;
158 int i, j;
159
160 recovi = data[disks];
161 recovj = data[disks+1];
162 spare = data[disks+2];
163
164 makedata(disks);
165
166 /* Nuke syndromes */
167 memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);
168 memset(page_address(data[disks-1]), 0xee, PAGE_SIZE);
169
170 /* Generate assumed good syndrome */
171 init_completion(&cmp);
172 init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
173 tx = async_gen_syndrome(dataptrs, dataoffs, disks, PAGE_SIZE, &submit);
174 async_tx_issue_pending(tx);
175
176 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {
177 pr("error: initial gen_syndrome(%d) timed out\n", disks);
178 return 1;
179 }
180
181 pr("testing the %d-disk case...\n", disks);
182 for (i = 0; i < disks-1; i++)
183 for (j = i+1; j < disks; j++) {
184 (*tests)++;
185 err += test_disks(i, j, disks);
186 }
187
188 return err;
189 }
190
191
192 static int __init raid6_test(void)
193 {
194 int err = 0;
195 int tests = 0;
196 int i;
197
198 for (i = 0; i < NDISKS+3; i++) {
199 data[i] = alloc_page(GFP_KERNEL);
200 if (!data[i]) {
201 while (i--)
202 put_page(data[i]);
203 return -ENOMEM;
204 }
205 }
206
207 /* the 4-disk and 5-disk cases are special for the recovery code */
208 if (NDISKS > 4)
209 err += test(4, &tests);
210 if (NDISKS > 5)
211 err += test(5, &tests);
212 /* the 11 and 12 disk cases are special for ioatdma (p-disabled
213 * q-continuation without extended descriptor)
214 */
215 if (NDISKS > 12) {
216 err += test(11, &tests);
217 err += test(12, &tests);
218 }
219
220 /* the 24 disk case is special for ioatdma as it is the boundary point
221 * at which it needs to switch from 8-source ops to 16-source
222 * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set)
223 */
224 if (NDISKS > 24)
225 err += test(24, &tests);
226
227 err += test(NDISKS, &tests);
228
229 pr("\n");
230 pr("complete (%d tests, %d failure%s)\n",
231 tests, err, err == 1 ? "" : "s");
232
233 for (i = 0; i < NDISKS+3; i++)
234 put_page(data[i]);
235
236 return 0;
237 }
238
239 static void __exit raid6_test_exit(void)
240 {
241 }
242
243 /* when compiled-in wait for drivers to load first (assumes dma drivers
244 * are also compiled-in)
245 */
246 late_initcall(raid6_test);
247 module_exit(raid6_test_exit);
248 MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
249 MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");
250 MODULE_LICENSE("GPL");
251
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