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/random.h> 24 25 #undef pr 26 #define pr(fmt, args...) pr_info("raid6test: " fmt, ##args) 27 28 #define NDISKS 16 /* Including P and Q */ 29 30 static struct page *dataptrs[NDISKS]; 31 static struct page *data[NDISKS+3]; 32 static struct page *spare; 33 static struct page *recovi; 34 static struct page *recovj; 35 36 static void callback(void *param) 37 { 38 struct completion *cmp = param; 39 40 complete(cmp); 41 } 42 43 static void makedata(int disks) 44 { 45 int i, j; 46 47 for (i = 0; i < disks; i++) { 48 for (j = 0; j < PAGE_SIZE/sizeof(u32); j += sizeof(u32)) { 49 u32 *p = page_address(data[i]) + j; 50 51 *p = random32(); 52 } 53 54 dataptrs[i] = data[i]; 55 } 56 } 57 58 static char disk_type(int d, int disks) 59 { 60 if (d == disks - 2) 61 return 'P'; 62 else if (d == disks - 1) 63 return 'Q'; 64 else 65 return 'D'; 66 } 67 68 /* Recover two failed blocks. */ 69 static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs) 70 { 71 struct async_submit_ctl submit; 72 addr_conv_t addr_conv[disks]; 73 struct completion cmp; 74 struct dma_async_tx_descriptor *tx = NULL; 75 enum sum_check_flags result = ~0; 76 77 if (faila > failb) 78 swap(faila, failb); 79 80 if (failb == disks-1) { 81 if (faila == disks-2) { 82 /* P+Q failure. Just rebuild the syndrome. */ 83 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); 84 tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); 85 } else { 86 struct page *blocks[disks]; 87 struct page *dest; 88 int count = 0; 89 int i; 90 91 /* data+Q failure. Reconstruct data from P, 92 * then rebuild syndrome 93 */ 94 for (i = disks; i-- ; ) { 95 if (i == faila || i == failb) 96 continue; 97 blocks[count++] = ptrs[i]; 98 } 99 dest = ptrs[faila]; 100 init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL, 101 NULL, NULL, addr_conv); 102 tx = async_xor(dest, blocks, 0, count, bytes, &submit); 103 104 init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv); 105 tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit); 106 } 107 } else { 108 if (failb == disks-2) { 109 /* data+P failure. */ 110 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); 111 tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit); 112 } else { 113 /* data+data failure. */ 114 init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv); 115 tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit); 116 } 117 } 118 init_completion(&cmp); 119 init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv); 120 tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit); 121 async_tx_issue_pending(tx); 122 123 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) 124 pr("%s: timeout! (faila: %d failb: %d disks: %d)\n", 125 __func__, faila, failb, disks); 126 127 if (result != 0) 128 pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n", 129 __func__, faila, failb, result); 130 } 131 132 static int test_disks(int i, int j, int disks) 133 { 134 int erra, errb; 135 136 memset(page_address(recovi), 0xf0, PAGE_SIZE); 137 memset(page_address(recovj), 0xba, PAGE_SIZE); 138 139 dataptrs[i] = recovi; 140 dataptrs[j] = recovj; 141 142 raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs); 143 144 erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE); 145 errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE); 146 147 pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n", 148 __func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks), 149 (!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB"); 150 151 dataptrs[i] = data[i]; 152 dataptrs[j] = data[j]; 153 154 return erra || errb; 155 } 156 157 static int test(int disks, int *tests) 158 { 159 addr_conv_t addr_conv[disks]; 160 struct dma_async_tx_descriptor *tx; 161 struct async_submit_ctl submit; 162 struct completion cmp; 163 int err = 0; 164 int i, j; 165 166 recovi = data[disks]; 167 recovj = data[disks+1]; 168 spare = data[disks+2]; 169 170 makedata(disks); 171 172 /* Nuke syndromes */ 173 memset(page_address(data[disks-2]), 0xee, PAGE_SIZE); 174 memset(page_address(data[disks-1]), 0xee, PAGE_SIZE); 175 176 /* Generate assumed good syndrome */ 177 init_completion(&cmp); 178 init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv); 179 tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit); 180 async_tx_issue_pending(tx); 181 182 if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) { 183 pr("error: initial gen_syndrome(%d) timed out\n", disks); 184 return 1; 185 } 186 187 pr("testing the %d-disk case...\n", disks); 188 for (i = 0; i < disks-1; i++) 189 for (j = i+1; j < disks; j++) { 190 (*tests)++; 191 err += test_disks(i, j, disks); 192 } 193 194 return err; 195 } 196 197 198 static int raid6_test(void) 199 { 200 int err = 0; 201 int tests = 0; 202 int i; 203 204 for (i = 0; i < NDISKS+3; i++) { 205 data[i] = alloc_page(GFP_KERNEL); 206 if (!data[i]) { 207 while (i--) 208 put_page(data[i]); 209 return -ENOMEM; 210 } 211 } 212 213 /* the 4-disk and 5-disk cases are special for the recovery code */ 214 if (NDISKS > 4) 215 err += test(4, &tests); 216 if (NDISKS > 5) 217 err += test(5, &tests); 218 err += test(NDISKS, &tests); 219 220 pr("\n"); 221 pr("complete (%d tests, %d failure%s)\n", 222 tests, err, err == 1 ? "" : "s"); 223 224 for (i = 0; i < NDISKS+3; i++) 225 put_page(data[i]); 226 227 return 0; 228 } 229 230 static void raid6_test_exit(void) 231 { 232 } 233 234 /* when compiled-in wait for drivers to load first (assumes dma drivers 235 * are also compliled-in) 236 */ 237 late_initcall(raid6_test); 238 module_exit(raid6_test_exit); 239 MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>"); 240 MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests"); 241 MODULE_LICENSE("GPL"); 242