crypto/async_tx/raid6test.c

   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 addr_conv_t addr_conv[NDISKS];
  32 static struct page *data[NDISKS+3];
  33 static struct page *spare;
  34 static struct page *recovi;
  35 static struct page *recovj;
  36
  37 static void callback(void *param)
  38 {
  39         struct completion *cmp = param;
  40
  41         complete(cmp);
  42 }
  43
  44 static void makedata(int disks)
  45 {
  46         int i, j;
  47
  48         for (i = 0; i < disks; i++) {
  49                 for (j = 0; j < PAGE_SIZE/sizeof(u32); j += sizeof(u32)) {
  50                         u32 *p = page_address(data[i]) + j;
  51
  52                         *p = random32();
  53                 }
  54
  55                 dataptrs[i] = data[i];
  56         }
  57 }
  58
  59 static char disk_type(int d, int disks)
  60 {
  61         if (d == disks - 2)
  62                 return 'P';
  63         else if (d == disks - 1)
  64                 return 'Q';
  65         else
  66                 return 'D';
  67 }
  68
  69 /* Recover two failed blocks. */
  70 static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs)
  71 {
  72         struct async_submit_ctl submit;
  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         struct dma_async_tx_descriptor *tx;
 160         struct async_submit_ctl submit;
 161         struct completion cmp;
 162         int err = 0;
 163         int i, j;
 164
 165         recovi = data[disks];
 166         recovj = data[disks+1];
 167         spare  = data[disks+2];
 168
 169         makedata(disks);
 170
 171         /* Nuke syndromes */
 172         memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);
 173         memset(page_address(data[disks-1]), 0xee, PAGE_SIZE);
 174
 175         /* Generate assumed good syndrome */
 176         init_completion(&cmp);
 177         init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
 178         tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit);
 179         async_tx_issue_pending(tx);
 180
 181         if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {
 182                 pr("error: initial gen_syndrome(%d) timed out\n", disks);
 183                 return 1;
 184         }
 185
 186         pr("testing the %d-disk case...\n", disks);
 187         for (i = 0; i < disks-1; i++)
 188                 for (j = i+1; j < disks; j++) {
 189                         (*tests)++;
 190                         err += test_disks(i, j, disks);
 191                 }
 192
 193         return err;
 194 }
 195
 196
 197 static int raid6_test(void)
 198 {
 199         int err = 0;
 200         int tests = 0;
 201         int i;
 202
 203         for (i = 0; i < NDISKS+3; i++) {
 204                 data[i] = alloc_page(GFP_KERNEL);
 205                 if (!data[i]) {
 206                         while (i--)
 207                                 put_page(data[i]);
 208                         return -ENOMEM;
 209                 }
 210         }
 211
 212         /* the 4-disk and 5-disk cases are special for the recovery code */
 213         if (NDISKS > 4)
 214                 err += test(4, &tests);
 215         if (NDISKS > 5)
 216                 err += test(5, &tests);
 217         err += test(NDISKS, &tests);
 218
 219         pr("\n");
 220         pr("complete (%d tests, %d failure%s)\n",
 221            tests, err, err == 1 ? "" : "s");
 222
 223         for (i = 0; i < NDISKS+3; i++)
 224                 put_page(data[i]);
 225
 226         return 0;
 227 }
 228
 229 static void raid6_test_exit(void)
 230 {
 231 }
 232
 233 /* when compiled-in wait for drivers to load first (assumes dma drivers
 234  * are also compliled-in)
 235  */
 236 late_initcall(raid6_test);
 237 module_exit(raid6_test_exit);
 238 MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
 239 MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");
 240 MODULE_LICENSE("GPL");