/*
* asynchronous raid6 recovery self test
* Copyright (c) 2009, Intel Corporation.
*
* based on drivers/md/raid6test/test.c:
* Copyright 2002-2007 H. Peter Anvin
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/async_tx.h>
#include <linux/gfp.h>
#include <linux/random.h>
#undef pr
#define pr(fmt, args...) pr_info("raid6test: " fmt, ##args)
#define NDISKS 16 /* Including P and Q */
static struct page *dataptrs[NDISKS];
static addr_conv_t addr_conv[NDISKS];
static struct page *data[NDISKS+3];
static struct page *spare;
static struct page *recovi;
static struct page *recovj;
static void callback(void *param)
{
struct completion *cmp = param;
complete(cmp);
}
static void makedata(int disks)
{
int i, j;
for (i = 0; i < disks; i++) {
for (j = 0; j < PAGE_SIZE/sizeof(u32); j += sizeof(u32)) {
u32 *p = page_address(data[i]) + j;
*p = random32();
}
dataptrs[i] = data[i];
}
}
static char disk_type(int d, int disks)
{
if (d == disks - 2)
return 'P';
else if (d == disks - 1)
return 'Q';
else
return 'D';
}
/* Recover two failed blocks. */
static void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, struct page **ptrs)
{
struct async_submit_ctl submit;
struct completion cmp;
struct dma_async_tx_descriptor *tx = NULL;
enum sum_check_flags result = ~0;
if (faila > failb)
swap(faila, failb);
if (failb == disks-1) {
if (faila == disks-2) {
/* P+Q failure. Just rebuild the syndrome. */
init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
} else {
struct page *blocks[disks];
struct page *dest;
int count = 0;
int i;
/* data+Q failure. Reconstruct data from P,
* then rebuild syndrome
*/
for (i = disks; i-- ; ) {
if (i == faila || i == failb)
continue;
blocks[count++] = ptrs[i];
}
dest = ptrs[faila];
init_async_submit(&submit, ASYNC_TX_XOR_ZERO_DST, NULL,
NULL, NULL, addr_conv);
tx = async_xor(dest, blocks, 0, count, bytes, &submit);
init_async_submit(&submit, 0, tx, NULL, NULL, addr_conv);
tx = async_gen_syndrome(ptrs, 0, disks, bytes, &submit);
}
} else {
if (failb == disks-2) {
/* data+P failure. */
init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
tx = async_raid6_datap_recov(disks, bytes, faila, ptrs, &submit);
} else {
/* data+data failure. */
init_async_submit(&submit, 0, NULL, NULL, NULL, addr_conv);
tx = async_raid6_2data_recov(disks, bytes, faila, failb, ptrs, &submit);
}
}
init_completion(&cmp);
init_async_submit(&submit, ASYNC_TX_ACK, tx, callback, &cmp, addr_conv);
tx = async_syndrome_val(ptrs, 0, disks, bytes, &result, spare, &submit);
async_tx_issue_pending(tx);
if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0)
pr("%s: timeout! (faila: %d failb: %d disks: %d)\n",
__func__, faila, failb, disks);
if (result != 0)
pr("%s: validation failure! faila: %d failb: %d sum_check_flags: %x\n",
__func__, faila, failb, result);
}
static int test_disks(int i, int j, int disks)
{
int erra, errb;
memset(page_address(recovi), 0xf0, PAGE_SIZE);
memset(page_address(recovj), 0xba, PAGE_SIZE);
dataptrs[i] = recovi;
dataptrs[j] = recovj;
raid6_dual_recov(disks, PAGE_SIZE, i, j, dataptrs);
erra = memcmp(page_address(data[i]), page_address(recovi), PAGE_SIZE);
errb = memcmp(page_address(data[j]), page_address(recovj), PAGE_SIZE);
pr("%s(%d, %d): faila=%3d(%c) failb=%3d(%c) %s\n",
__func__, i, j, i, disk_type(i, disks), j, disk_type(j, disks),
(!erra && !errb) ? "OK" : !erra ? "ERRB" : !errb ? "ERRA" : "ERRAB");
dataptrs[i] = data[i];
dataptrs[j] = data[j];
return erra || errb;
}
static int test(int disks, int *tests)
{
struct dma_async_tx_descriptor *tx;
struct async_submit_ctl submit;
struct completion cmp;
int err = 0;
int i, j;
recovi = data[disks];
recovj = data[disks+1];
spare = data[disks+2];
makedata(disks);
/* Nuke syndromes */
memset(page_address(data[disks-2]), 0xee, PAGE_SIZE);
memset(page_address(data[disks-1]), 0xee, PAGE_SIZE);
/* Generate assumed good syndrome */
init_completion(&cmp);
init_async_submit(&submit, ASYNC_TX_ACK, NULL, callback, &cmp, addr_conv);
tx = async_gen_syndrome(dataptrs, 0, disks, PAGE_SIZE, &submit);
async_tx_issue_pending(tx);
if (wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000)) == 0) {
pr("error: initial gen_syndrome(%d) timed out\n", disks);
return 1;
}
pr("testing the %d-disk case...\n", disks);
for (i = 0; i < disks-1; i++)
for (j = i+1; j < disks; j++) {
(*tests)++;
err += test_disks(i, j, disks);
}
return err;
}
static int raid6_test(void)
{
int err = 0;
int tests = 0;
int i;
for (i = 0; i < NDISKS+3; i++) {
data[i] = alloc_page(GFP_KERNEL);
if (!data[i]) {
while (i--)
put_page(data[i]);
return -ENOMEM;
}
}
/* the 4-disk and 5-disk cases are special for the recovery code */
if (NDISKS > 4)
err += test(4, &tests);
if (NDISKS > 5)
err += test(5, &tests);
/* the 11 and 12 disk cases are special for ioatdma (p-disabled
* q-continuation without extended descriptor)
*/
if (NDISKS > 12) {
err += test(11, &tests);
err += test(12, &tests);
}
err += test(NDISKS, &tests);
pr("\n");
pr("complete (%d tests, %d failure%s)\n",
tests, err, err == 1 ? "" : "s");
for (i = 0; i < NDISKS+3; i++)
put_page(data[i]);
return 0;
}
static void raid6_test_exit(void)
{
}
/* when compiled-in wait for drivers to load first (assumes dma drivers
* are also compliled-in)
*/
late_initcall(raid6_test);
module_exit(raid6_test_exit);
MODULE_AUTHOR("Dan Williams <dan.j.williams@intel.com>");
MODULE_DESCRIPTION("asynchronous RAID-6 recovery self tests");
MODULE_LICENSE("GPL");
