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