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 64 /* 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 40 static void callback(void *param) 41 { 42 struct completion *cmp = param; 43 44 complete(cmp); 45 } 46 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 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. */ 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 } 129 130 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 } 154 155 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 } 193 194 195 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 } 222 223 /* the 24 disk case is special for ioatdma as it is the boudary point 224 * at which it needs to switch from 8-source ops to 16-source 225 * ops for continuation (assumes DMA_HAS_PQ_CONTINUE is not set) 226 */ 227 if (NDISKS > 24) 228 err += test(24, &tests); 229 230 err += test(NDISKS, &tests); 231 232 pr("\n"); 233 pr("complete (%d tests, %d failure%s)\n", 234 tests, err, err == 1 ? "" : "s"); 235 236 for (i = 0; i < NDISKS+3; i++) 237 put_page(data[i]); 238 239 return 0; 240 } 241 242 static void raid6_test_exit(void) 243 { 244 } 245 246 /* when compiled-in wait for drivers to load first (assumes dma drivers 247 * are also compliled-in) 248 */ 249 late_initcall(raid6_test); 250 module_exit(raid6_test_exit); 251 MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>"); 252 MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests"); 253 MODULE_LICENSE("GPL"); 254