/*
* mdadm - manage Linux "md" devices aka RAID arrays.
*
* Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author: Neil Brown
* Email: <neilb@suse.de>
*/
#include "mdadm.h"
#include <stdint.h>
/* To restripe, we read from old geometry to a buffer, and
* read from buffer to new geometry.
* When reading, we might have missing devices and so could need
* to reconstruct.
* When writing, we need to create correct parity and Q.
*
*/
int geo_map(int block, unsigned long long stripe, int raid_disks,
int level, int layout)
{
/* On the given stripe, find which disk in the array will have
* block numbered 'block'.
* '-1' means the parity block.
* '-2' means the Q syndrome.
*/
int pd;
/* layout is not relevant for raid0 and raid4 */
if ((level == 0) ||
(level == 4))
layout = 0;
switch(level*100 + layout) {
case 000:
case 400:
case 500 + ALGORITHM_PARITY_N:
/* raid 4 isn't messed around by parity blocks */
if (block == -1)
return raid_disks-1; /* parity block */
return block;
case 500 + ALGORITHM_LEFT_ASYMMETRIC:
pd = (raid_disks-1) - stripe % raid_disks;
if (block == -1)
return pd;
if (block >= pd)
block++;
return block;
case 500 + ALGORITHM_RIGHT_ASYMMETRIC:
pd = stripe % raid_disks;
if (block == -1)
return pd;
if (block >= pd)
block++;
return block;
case 500 + ALGORITHM_LEFT_SYMMETRIC:
pd = (raid_disks - 1) - stripe % raid_disks;
if (block == -1)
return pd;
return (pd + 1 + block) % raid_disks;
case 500 + ALGORITHM_RIGHT_SYMMETRIC:
pd = stripe % raid_disks;
if (block == -1)
return pd;
return (pd + 1 + block) % raid_disks;
case 500 + ALGORITHM_PARITY_0:
return block + 1;
case 600 + ALGORITHM_PARITY_N_6:
if (block == -2)
return raid_disks - 1;
if (block == -1)
return raid_disks - 2; /* parity block */
return block;
case 600 + ALGORITHM_LEFT_ASYMMETRIC_6:
if (block == -2)
return raid_disks - 1;
raid_disks--;
pd = (raid_disks-1) - stripe % raid_disks;
if (block == -1)
return pd;
if (block >= pd)
block++;
return block;
case 600 + ALGORITHM_RIGHT_ASYMMETRIC_6:
if (block == -2)
return raid_disks - 1;
raid_disks--;
pd = stripe % raid_disks;
if (block == -1)
return pd;
if (block >= pd)
block++;
return block;
case 600 + ALGORITHM_LEFT_SYMMETRIC_6:
if (block == -2)
return raid_disks - 1;
raid_disks--;
pd = (raid_disks - 1) - stripe % raid_disks;
if (block == -1)
return pd;
return (pd + 1 + block) % raid_disks;
case 600 + ALGORITHM_RIGHT_SYMMETRIC_6:
if (block == -2)
return raid_disks - 1;
raid_disks--;
pd = stripe % raid_disks;
if (block == -1)
return pd;
return (pd + 1 + block) % raid_disks;
case 600 + ALGORITHM_PARITY_0_6:
if (block == -2)
return raid_disks - 1;
return block + 1;
case 600 + ALGORITHM_PARITY_0:
if (block == -1)
return 0;
if (block == -2)
return 1;
return block + 2;
case 600 + ALGORITHM_LEFT_ASYMMETRIC:
pd = raid_disks - 1 - (stripe % raid_disks);
if (block == -1)
return pd;
if (block == -2)
return (pd+1) % raid_disks;
if (pd == raid_disks - 1)
return block+1;
if (block >= pd)
return block+2;
return block;
case 600 + ALGORITHM_ROTATING_ZERO_RESTART:
/* Different order for calculating Q, otherwize same as ... */
case 600 + ALGORITHM_RIGHT_ASYMMETRIC:
pd = stripe % raid_disks;
if (block == -1)
return pd;
if (block == -2)
return (pd+1) % raid_disks;
if (pd == raid_disks - 1)
return block+1;
if (block >= pd)
return block+2;
return block;
case 600 + ALGORITHM_LEFT_SYMMETRIC:
pd = raid_disks - 1 - (stripe % raid_disks);
if (block == -1)
return pd;
if (block == -2)
return (pd+1) % raid_disks;
return (pd + 2 + block) % raid_disks;
case 600 + ALGORITHM_RIGHT_SYMMETRIC:
pd = stripe % raid_disks;
if (block == -1)
return pd;
if (block == -2)
return (pd+1) % raid_disks;
return (pd + 2 + block) % raid_disks;
case 600 + ALGORITHM_ROTATING_N_RESTART:
/* Same a left_asymmetric, by first stripe is
* D D D P Q rather than
* Q D D D P
*/
pd = raid_disks - 1 - ((stripe + 1) % raid_disks);
if (block == -1)
return pd;
if (block == -2)
return (pd+1) % raid_disks;
if (pd == raid_disks - 1)
return block+1;
if (block >= pd)
return block+2;
return block;
case 600 + ALGORITHM_ROTATING_N_CONTINUE:
/* Same as left_symmetric but Q is before P */
pd = raid_disks - 1 - (stripe % raid_disks);
if (block == -1)
return pd;
if (block == -2)
return (pd+raid_disks-1) % raid_disks;
return (pd + 1 + block) % raid_disks;
}
return -1;
}
int is_ddf(int layout)
{
switch (layout)
{
default:
return 0;
case ALGORITHM_ROTATING_N_CONTINUE:
case ALGORITHM_ROTATING_N_RESTART:
case ALGORITHM_ROTATING_ZERO_RESTART:
return 1;
}
}
void xor_blocks(char *target, char **sources, int disks, int size)
{
int i, j;
/* Amazingly inefficient... */
for (i=0; i<size; i++) {
char c = 0;
for (j=0 ; j<disks; j++)
c ^= sources[j][i];
target[i] = c;
}
}
void qsyndrome(uint8_t *p, uint8_t *q, uint8_t **sources, int disks, int size)
{
int d, z;
uint8_t wq0, wp0, wd0, w10, w20;
for ( d = 0; d < size; d++) {
wq0 = wp0 = sources[disks-1][d];
for ( z = disks-2 ; z >= 0 ; z-- ) {
wd0 = sources[z][d];
wp0 ^= wd0;
w20 = (wq0&0x80) ? 0xff : 0x00;
w10 = (wq0 << 1) & 0xff;
w20 &= 0x1d;
w10 ^= w20;
wq0 = w10 ^ wd0;
}
p[d] = wp0;
q[d] = wq0;
}
}
/*
* The following was taken from linux/drivers/md/mktables.c, and modified
* to create in-memory tables rather than C code
*/
static uint8_t gfmul(uint8_t a, uint8_t b)
{
uint8_t v = 0;
while (b) {
if (b & 1)
v ^= a;
a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
b >>= 1;
}
return v;
}
static uint8_t gfpow(uint8_t a, int b)
{
uint8_t v = 1;
b %= 255;
if (b < 0)
b += 255;
while (b) {
if (b & 1)
v = gfmul(v, a);
a = gfmul(a, a);
b >>= 1;
}
return v;
}
int tables_ready = 0;
uint8_t raid6_gfmul[256][256];
uint8_t raid6_gfexp[256];
uint8_t raid6_gfinv[256];
uint8_t raid6_gfexi[256];
uint8_t raid6_gflog[256];
uint8_t raid6_gfilog[256];
void make_tables(void)
{
int i, j;
uint8_t v;
uint32_t b, log;
/* Compute multiplication table */
for (i = 0; i < 256; i++)
for (j = 0; j < 256; j++)
raid6_gfmul[i][j] = gfmul(i, j);
/* Compute power-of-2 table (exponent) */
v = 1;
for (i = 0; i < 256; i++) {
raid6_gfexp[i] = v;
v = gfmul(v, 2);
if (v == 1)
v = 0; /* For entry 255, not a real entry */
}
/* Compute inverse table x^-1 == x^254 */
for (i = 0; i < 256; i++)
raid6_gfinv[i] = gfpow(i, 254);
/* Compute inv(2^x + 1) (exponent-xor-inverse) table */
for (i = 0; i < 256; i ++)
raid6_gfexi[i] = raid6_gfinv[raid6_gfexp[i] ^ 1];
/* Compute log and inverse log */
/* Modified code from:
* https://web.eecs.utk.edu/~plank/plank/papers/CS-96-332.html
*/
b = 1;
raid6_gflog[0] = 0;
raid6_gfilog[255] = 0;
for (log = 0; log < 255; log++) {
raid6_gflog[b] = (uint8_t) log;
raid6_gfilog[log] = (uint8_t) b;
b = b << 1;
if (b & 256) b = b ^ 0435;
}
tables_ready = 1;
}
uint8_t *zero;
int zero_size;
void ensure_zero_has_size(int chunk_size)
{
if (zero == NULL || chunk_size > zero_size) {
if (zero)
free(zero);
zero = xcalloc(1, chunk_size);
zero_size = chunk_size;
}
}
/* Following was taken from linux/drivers/md/raid6recov.c */
/* Recover two failed data blocks. */
void raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
uint8_t **ptrs, int neg_offset)
{
uint8_t *p, *q, *dp, *dq;
uint8_t px, qx, db;
const uint8_t *pbmul; /* P multiplier table for B data */
const uint8_t *qmul; /* Q multiplier table (for both) */
if (faila > failb) {
int t = faila;
faila = failb;
failb = t;
}
if (neg_offset) {
p = ptrs[-1];
q = ptrs[-2];
} else {
p = ptrs[disks-2];
q = ptrs[disks-1];
}
/* Compute syndrome with zero for the missing data pages
Use the dead data pages as temporary storage for
delta p and delta q */
dp = ptrs[faila];
ptrs[faila] = zero;
dq = ptrs[failb];
ptrs[failb] = zero;
qsyndrome(dp, dq, ptrs, disks-2, bytes);
/* Restore pointer table */
ptrs[faila] = dp;
ptrs[failb] = dq;
/* Now, pick the proper data tables */
pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];
/* Now do it... */
while ( bytes-- ) {
px = *p ^ *dp;
qx = qmul[*q ^ *dq];
*dq++ = db = pbmul[px] ^ qx; /* Reconstructed B */
*dp++ = db ^ px; /* Reconstructed A */
p++; q++;
}
}
/* Recover failure of one data block plus the P block */
void raid6_datap_recov(int disks, size_t bytes, int faila, uint8_t **ptrs,
int neg_offset)
{
uint8_t *p, *q, *dq;
const uint8_t *qmul; /* Q multiplier table */
if (neg_offset) {
p = ptrs[-1];
q = ptrs[-2];
} else {
p = ptrs[disks-2];
q = ptrs[disks-1];
}
/* Compute syndrome with zero for the missing data page
Use the dead data page as temporary storage for delta q */
dq = ptrs[faila];
ptrs[faila] = zero;
qsyndrome(p, dq, ptrs, disks-2, bytes);
/* Restore pointer table */
ptrs[faila] = dq;
/* Now, pick the proper data tables */
qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];
/* Now do it... */
while ( bytes-- ) {
*p++ ^= *dq = qmul[*q ^ *dq];
q++; dq++;
}
}
/* Try to find out if a specific disk has a problem */
int raid6_check_disks(int data_disks, int start, int chunk_size,
int level, int layout, int diskP, int diskQ,
uint8_t *p, uint8_t *q, char **stripes)
{
int i;
int data_id, diskD;
uint8_t Px, Qx;
int curr_broken_disk = -1;
int prev_broken_disk = -1;
int broken_status = 0;
for(i = 0; i < chunk_size; i++) {
Px = (uint8_t)stripes[diskP][i] ^ (uint8_t)p[i];
Qx = (uint8_t)stripes[diskQ][i] ^ (uint8_t)q[i];
if((Px != 0) && (Qx == 0))
curr_broken_disk = diskP;
if((Px == 0) && (Qx != 0))
curr_broken_disk = diskQ;
if((Px != 0) && (Qx != 0)) {
data_id = (raid6_gflog[Qx] - raid6_gflog[Px]);
if(data_id < 0) data_id += 255;
diskD = geo_map(data_id, start/chunk_size,
data_disks + 2, level, layout);
curr_broken_disk = diskD;
}
if((Px == 0) && (Qx == 0))
curr_broken_disk = prev_broken_disk;
if(curr_broken_disk >= data_disks + 2)
broken_status = 2;
switch(broken_status) {
case 0:
if(curr_broken_disk != -1) {
prev_broken_disk = curr_broken_disk;
broken_status = 1;
}
break;
case 1:
if(curr_broken_disk != prev_broken_disk)
broken_status = 2;
break;
case 2:
default:
curr_broken_disk = prev_broken_disk = -2;
break;
}
}
return curr_broken_disk;
}
/*******************************************************************************
* Function: save_stripes
* Description:
* Function reads data (only data without P and Q) from array and writes
* it to buf and opcjonaly to backup files
* Parameters:
* source : A list of 'fds' of the active disks.
* Some may be absent
* offsets : A list of offsets on disk belonging
* to the array [bytes]
* raid_disks : geometry: number of disks in the array
* chunk_size : geometry: chunk size [bytes]
* level : geometry: RAID level
* layout : geometry: layout
* nwrites : number of backup files
* dest : A list of 'fds' for mirrored targets
* (e.g. backup files). They are already seeked to right
* (write) location. If NULL, data will be wrote
* to the buf only
* start : start address of data to read (must be stripe-aligned)
* [bytes]
* length - : length of data to read (must be stripe-aligned)
* [bytes]
* buf : buffer for data. It is large enough to hold
* one stripe. It is stripe aligned
* Returns:
* 0 : success
* -1 : fail
******************************************************************************/
int save_stripes(int *source, unsigned long long *offsets,
int raid_disks, int chunk_size, int level, int layout,
int nwrites, int *dest,
unsigned long long start, unsigned long long length,
char *buf)
{
int len;
int data_disks = raid_disks - (level == 0 ? 0 : level <=5 ? 1 : 2);
int disk;
int i;
unsigned long long length_test;
if (!tables_ready)
make_tables();
ensure_zero_has_size(chunk_size);
len = data_disks * chunk_size;
length_test = length / len;
length_test *= len;
if (length != length_test) {
dprintf("Error: save_stripes(): Data are not alligned. EXIT\n");
dprintf("\tArea for saving stripes (length) = %llu\n", length);
dprintf("\tWork step (len) = %i\n", len);
dprintf("\tExpected save area (length_test) = %llu\n",
length_test);
abort();
}
while (length > 0) {
int failed = 0;
int fdisk[3], fblock[3];
for (disk = 0; disk < raid_disks ; disk++) {
unsigned long long offset;
int dnum;
offset = (start/chunk_size/data_disks)*chunk_size;
dnum = geo_map(disk < data_disks ? disk : data_disks - disk - 1,
start/chunk_size/data_disks,
raid_disks, level, layout);
if (dnum < 0) abort();
if (source[dnum] < 0 ||
lseek64(source[dnum],
offsets[dnum] + offset, 0) < 0 ||
read(source[dnum], buf+disk * chunk_size,
chunk_size) != chunk_size) {
if (failed <= 2) {
fdisk[failed] = dnum;
fblock[failed] = disk;
failed++;
}
}
}
if (failed == 0 || fblock[0] >= data_disks)
/* all data disks are good */
;
else if (failed == 1 || fblock[1] >= data_disks+1) {
/* one failed data disk and good parity */
char *bufs[data_disks];
for (i=0; i < data_disks; i++)
if (fblock[0] == i)
bufs[i] = buf + data_disks*chunk_size;
else
bufs[i] = buf + i*chunk_size;
xor_blocks(buf + fblock[0]*chunk_size,
bufs, data_disks, chunk_size);
} else if (failed > 2 || level != 6)
/* too much failure */
return -1;
else {
/* RAID6 computations needed. */
uint8_t *bufs[data_disks+4];
int qdisk;
int syndrome_disks;
disk = geo_map(-1, start/chunk_size/data_disks,
raid_disks, level, layout);
qdisk = geo_map(-2, start/chunk_size/data_disks,
raid_disks, level, layout);
if (is_ddf(layout)) {
/* q over 'raid_disks' blocks, in device order.
* 'p' and 'q' get to be all zero
*/
for (i = 0; i < raid_disks; i++)
bufs[i] = zero;
for (i = 0; i < data_disks; i++) {
int dnum = geo_map(i,
start/chunk_size/data_disks,
raid_disks, level, layout);
int snum;
/* i is the logical block number, so is index to 'buf'.
* dnum is physical disk number
* and thus the syndrome number.
*/
snum = dnum;
bufs[snum] = (uint8_t*)buf + chunk_size * i;
}
syndrome_disks = raid_disks;
} else {
/* for md, q is over 'data_disks' blocks,
* starting immediately after 'q'
* Note that for the '_6' variety, the p block
* makes a hole that we need to be careful of.
*/
int j;
int snum = 0;
for (j = 0; j < raid_disks; j++) {
int dnum = (qdisk + 1 + j) % raid_disks;
if (dnum == disk || dnum == qdisk)
continue;
for (i = 0; i < data_disks; i++)
if (geo_map(i,
start/chunk_size/data_disks,
raid_disks, level, layout) == dnum)
break;
/* i is the logical block number, so is index to 'buf'.
* dnum is physical disk number
* snum is syndrome disk for which 0 is immediately after Q
*/
bufs[snum] = (uint8_t*)buf + chunk_size * i;
if (fblock[0] == i)
fdisk[0] = snum;
if (fblock[1] == i)
fdisk[1] = snum;
snum++;
}
syndrome_disks = data_disks;
}
/* Place P and Q blocks at end of bufs */
bufs[syndrome_disks] = (uint8_t*)buf + chunk_size * data_disks;
bufs[syndrome_disks+1] = (uint8_t*)buf + chunk_size * (data_disks+1);
if (fblock[1] == data_disks)
/* One data failed, and parity failed */
raid6_datap_recov(syndrome_disks+2, chunk_size,
fdisk[0], bufs, 0);
else {
/* Two data blocks failed, P,Q OK */
raid6_2data_recov(syndrome_disks+2, chunk_size,
fdisk[0], fdisk[1], bufs, 0);
}
}
if (dest) {
for (i = 0; i < nwrites; i++)
if (write(dest[i], buf, len) != len)
return -1;
} else {
/* build next stripe in buffer */
buf += len;
}
length -= len;
start += len;
}
return 0;
}
/* Restore data:
* We are given:
* A list of 'fds' of the active disks. Some may be '-1' for not-available.
* A geometry: raid_disks, chunk_size, level, layout
* An 'fd' to read from. It is already seeked to the right (Read) location.
* A start and length.
* The length must be a multiple of the stripe size.
*
* We build a full stripe in memory and then write it out.
* We assume that there are enough working devices.
*/
int restore_stripes(int *dest, unsigned long long *offsets,
int raid_disks, int chunk_size, int level, int layout,
int source, unsigned long long read_offset,
unsigned long long start, unsigned long long length,
char *src_buf)
{
char *stripe_buf;
char **stripes = xmalloc(raid_disks * sizeof(char*));
char **blocks = xmalloc(raid_disks * sizeof(char*));
int i;
int rv;
int data_disks = raid_disks - (level == 0 ? 0 : level <= 5 ? 1 : 2);
if (posix_memalign((void**)&stripe_buf, 4096, raid_disks * chunk_size))
stripe_buf = NULL;
if (zero == NULL || chunk_size > zero_size) {
if (zero)
free(zero);
zero = xcalloc(1, chunk_size);
zero_size = chunk_size;
}
if (stripe_buf == NULL || stripes == NULL || blocks == NULL ||
zero == NULL) {
rv = -2;
goto abort;
}
for (i = 0; i < raid_disks; i++)
stripes[i] = stripe_buf + i * chunk_size;
while (length > 0) {
unsigned int len = data_disks * chunk_size;
unsigned long long offset;
int disk, qdisk;
int syndrome_disks;
if (length < len) {
rv = -3;
goto abort;
}
for (i = 0; i < data_disks; i++) {
int disk = geo_map(i, start/chunk_size/data_disks,
raid_disks, level, layout);
if (src_buf == NULL) {
/* read from file */
if (lseek64(source, read_offset, 0) !=
(off64_t)read_offset) {
rv = -1;
goto abort;
}
if (read(source,
stripes[disk],
chunk_size) != chunk_size) {
rv = -1;
goto abort;
}
} else {
/* read from input buffer */
memcpy(stripes[disk],
src_buf + read_offset,
chunk_size);
}
read_offset += chunk_size;
}
/* We have the data, now do the parity */
offset = (start/chunk_size/data_disks) * chunk_size;
switch (level) {
case 4:
case 5:
disk = geo_map(-1, start/chunk_size/data_disks,
raid_disks, level, layout);
for (i = 0; i < data_disks; i++)
blocks[i] = stripes[(disk+1+i) % raid_disks];
xor_blocks(stripes[disk], blocks, data_disks, chunk_size);
break;
case 6:
disk = geo_map(-1, start/chunk_size/data_disks,
raid_disks, level, layout);
qdisk = geo_map(-2, start/chunk_size/data_disks,
raid_disks, level, layout);
if (is_ddf(layout)) {
/* q over 'raid_disks' blocks, in device order.
* 'p' and 'q' get to be all zero
*/
for (i = 0; i < raid_disks; i++)
if (i == disk || i == qdisk)
blocks[i] = (char*)zero;
else
blocks[i] = stripes[i];
syndrome_disks = raid_disks;
} else {
/* for md, q is over 'data_disks' blocks,
* starting immediately after 'q'
*/
for (i = 0; i < data_disks; i++)
blocks[i] = stripes[(qdisk+1+i) % raid_disks];
syndrome_disks = data_disks;
}
qsyndrome((uint8_t*)stripes[disk],
(uint8_t*)stripes[qdisk],
(uint8_t**)blocks,
syndrome_disks, chunk_size);
break;
}
for (i=0; i < raid_disks ; i++)
if (dest[i] >= 0) {
if (lseek64(dest[i],
offsets[i]+offset, 0) < 0) {
rv = -1;
goto abort;
}
if (write(dest[i], stripes[i],
chunk_size) != chunk_size) {
rv = -1;
goto abort;
}
}
length -= len;
start += len;
}
rv = 0;
abort:
free(stripe_buf);
free(stripes);
free(blocks);
return rv;
}
#ifdef MAIN
int test_stripes(int *source, unsigned long long *offsets,
int raid_disks, int chunk_size, int level, int layout,
unsigned long long start, unsigned long long length)
{
/* ready the data and p (and q) blocks, and check we got them right */
char *stripe_buf = xmalloc(raid_disks * chunk_size);
char **stripes = xmalloc(raid_disks * sizeof(char*));
char **blocks = xmalloc(raid_disks * sizeof(char*));
uint8_t *p = xmalloc(chunk_size);
uint8_t *q = xmalloc(chunk_size);
int i;
int diskP, diskQ;
int data_disks = raid_disks - (level == 5 ? 1: 2);
if (!tables_ready)
make_tables();
for ( i = 0 ; i < raid_disks ; i++)
stripes[i] = stripe_buf + i * chunk_size;
while (length > 0) {
int disk;
for (i = 0 ; i < raid_disks ; i++) {
if ((lseek64(source[i], offsets[i]+start, 0) < 0) ||
(read(source[i], stripes[i], chunk_size) !=
chunk_size)) {
free(q);
free(p);
free(blocks);
free(stripes);
free(stripe_buf);
return -1;
}
}
for (i = 0 ; i < data_disks ; i++) {
int disk = geo_map(i, start/chunk_size, raid_disks,
level, layout);
blocks[i] = stripes[disk];
printf("%d->%d\n", i, disk);
}
switch(level) {
case 6:
qsyndrome(p, q, (uint8_t**)blocks, data_disks, chunk_size);
diskP = geo_map(-1, start/chunk_size, raid_disks,
level, layout);
if (memcmp(p, stripes[diskP], chunk_size) != 0) {
printf("P(%d) wrong at %llu\n", diskP,
start / chunk_size);
}
diskQ = geo_map(-2, start/chunk_size, raid_disks,
level, layout);
if (memcmp(q, stripes[diskQ], chunk_size) != 0) {
printf("Q(%d) wrong at %llu\n", diskQ,
start / chunk_size);
}
disk = raid6_check_disks(data_disks, start, chunk_size,
level, layout, diskP, diskQ,
p, q, stripes);
if(disk >= 0) {
printf("Possible failed disk: %d\n", disk);
}
if(disk == -2) {
printf("Failure detected, but disk unknown\n");
}
break;
}
length -= chunk_size;
start += chunk_size;
}
return 0;
}
unsigned long long getnum(char *str, char **err)
{
char *e;
unsigned long long rv = strtoull(str, &e, 10);
if (e==str || *e) {
*err = str;
return 0;
}
return rv;
}
char const Name[] = "test_restripe";
int main(int argc, char *argv[])
{
/* save/restore file raid_disks chunk_size level layout start length devices...
*/
int save;
int *fds;
char *file;
char *buf;
int storefd;
unsigned long long *offsets;
int raid_disks, chunk_size, level, layout;
unsigned long long start, length;
int i;
char *err = NULL;
if (argc < 10) {
fprintf(stderr, "Usage: test_stripe save/restore file raid_disks chunk_size level layout start length devices...\n");
exit(1);
}
if (strcmp(argv[1], "save")==0)
save = 1;
else if (strcmp(argv[1], "restore") == 0)
save = 0;
else if (strcmp(argv[1], "test") == 0)
save = 2;
else {
fprintf(stderr, "test_stripe: must give 'save' or 'restore'.\n");
exit(2);
}
file = argv[2];
raid_disks = getnum(argv[3], &err);
chunk_size = getnum(argv[4], &err);
level = getnum(argv[5], &err);
layout = getnum(argv[6], &err);
start = getnum(argv[7], &err);
length = getnum(argv[8], &err);
if (err) {
fprintf(stderr, "test_stripe: Bad number: %s\n", err);
exit(2);
}
if (argc != raid_disks + 9) {
fprintf(stderr, "test_stripe: wrong number of devices: want %d found %d\n",
raid_disks, argc-9);
exit(2);
}
fds = xmalloc(raid_disks * sizeof(*fds));
offsets = xcalloc(raid_disks, sizeof(*offsets));
storefd = open(file, O_RDWR);
if (storefd < 0) {
perror(file);
fprintf(stderr, "test_stripe: could not open %s.\n", file);
exit(3);
}
for (i=0; i<raid_disks; i++) {
char *p;
p = strchr(argv[9+i], ':');
if(p != NULL) {
*p++ = '\0';
offsets[i] = atoll(p) * 512;
}
fds[i] = open(argv[9+i], O_RDWR);
if (fds[i] < 0) {
perror(argv[9+i]);
fprintf(stderr,"test_stripe: cannot open %s.\n", argv[9+i]);
exit(3);
}
}
buf = xmalloc(raid_disks * chunk_size);
if (save == 1) {
int rv = save_stripes(fds, offsets,
raid_disks, chunk_size, level, layout,
1, &storefd,
start, length, buf);
if (rv != 0) {
fprintf(stderr,
"test_stripe: save_stripes returned %d\n", rv);
exit(1);
}
} else if (save == 2) {
int rv = test_stripes(fds, offsets,
raid_disks, chunk_size, level, layout,
start, length);
if (rv != 0) {
fprintf(stderr,
"test_stripe: test_stripes returned %d\n", rv);
exit(1);
}
} else {
int rv = restore_stripes(fds, offsets,
raid_disks, chunk_size, level, layout,
storefd, 0ULL,
start, length, NULL);
if (rv != 0) {
fprintf(stderr,
"test_stripe: restore_stripes returned %d\n",
rv);
exit(1);
}
}
exit(0);
}
#endif /* MAIN */