1039 lines
25 KiB
C
1039 lines
25 KiB
C
/*
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* mdadm - manage Linux "md" devices aka RAID arrays.
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*
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* Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
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*
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* Author: Neil Brown
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* Email: <neilb@suse.de>
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*/
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#include "mdadm.h"
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#include <stdint.h>
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/* To restripe, we read from old geometry to a buffer, and
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* read from buffer to new geometry.
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* When reading, we might have missing devices and so could need
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* to reconstruct.
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* When writing, we need to create correct parity and Q.
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*
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*/
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int geo_map(int block, unsigned long long stripe, int raid_disks,
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int level, int layout)
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{
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/* On the given stripe, find which disk in the array will have
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* block numbered 'block'.
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* '-1' means the parity block.
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* '-2' means the Q syndrome.
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*/
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int pd;
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/* layout is not relevant for raid0 and raid4 */
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if ((level == 0) ||
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(level == 4))
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layout = 0;
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switch(level*100 + layout) {
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case 000:
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case 400:
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case 500 + ALGORITHM_PARITY_N:
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/* raid 4 isn't messed around by parity blocks */
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if (block == -1)
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return raid_disks-1; /* parity block */
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return block;
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case 500 + ALGORITHM_LEFT_ASYMMETRIC:
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pd = (raid_disks-1) - stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block >= pd)
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block++;
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return block;
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case 500 + ALGORITHM_RIGHT_ASYMMETRIC:
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block >= pd)
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block++;
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return block;
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case 500 + ALGORITHM_LEFT_SYMMETRIC:
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pd = (raid_disks - 1) - stripe % raid_disks;
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if (block == -1)
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return pd;
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return (pd + 1 + block) % raid_disks;
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case 500 + ALGORITHM_RIGHT_SYMMETRIC:
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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return (pd + 1 + block) % raid_disks;
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case 500 + ALGORITHM_PARITY_0:
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return block + 1;
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case 600 + ALGORITHM_PARITY_N_6:
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if (block == -2)
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return raid_disks - 1;
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if (block == -1)
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return raid_disks - 2; /* parity block */
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return block;
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case 600 + ALGORITHM_LEFT_ASYMMETRIC_6:
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if (block == -2)
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return raid_disks - 1;
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raid_disks--;
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pd = (raid_disks-1) - stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block >= pd)
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block++;
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return block;
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case 600 + ALGORITHM_RIGHT_ASYMMETRIC_6:
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if (block == -2)
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return raid_disks - 1;
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raid_disks--;
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block >= pd)
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block++;
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return block;
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case 600 + ALGORITHM_LEFT_SYMMETRIC_6:
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if (block == -2)
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return raid_disks - 1;
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raid_disks--;
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pd = (raid_disks - 1) - stripe % raid_disks;
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if (block == -1)
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return pd;
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return (pd + 1 + block) % raid_disks;
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case 600 + ALGORITHM_RIGHT_SYMMETRIC_6:
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if (block == -2)
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return raid_disks - 1;
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raid_disks--;
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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return (pd + 1 + block) % raid_disks;
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case 600 + ALGORITHM_PARITY_0_6:
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if (block == -2)
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return raid_disks - 1;
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return block + 1;
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case 600 + ALGORITHM_PARITY_0:
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if (block == -1)
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return 0;
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if (block == -2)
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return 1;
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return block + 2;
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case 600 + ALGORITHM_LEFT_ASYMMETRIC:
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pd = raid_disks - 1 - (stripe % raid_disks);
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+1) % raid_disks;
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if (pd == raid_disks - 1)
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return block+1;
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if (block >= pd)
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return block+2;
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return block;
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case 600 + ALGORITHM_ROTATING_ZERO_RESTART:
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/* Different order for calculating Q, otherwize same as ... */
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case 600 + ALGORITHM_RIGHT_ASYMMETRIC:
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+1) % raid_disks;
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if (pd == raid_disks - 1)
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return block+1;
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if (block >= pd)
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return block+2;
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return block;
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case 600 + ALGORITHM_LEFT_SYMMETRIC:
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pd = raid_disks - 1 - (stripe % raid_disks);
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+1) % raid_disks;
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return (pd + 2 + block) % raid_disks;
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case 600 + ALGORITHM_RIGHT_SYMMETRIC:
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pd = stripe % raid_disks;
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+1) % raid_disks;
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return (pd + 2 + block) % raid_disks;
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case 600 + ALGORITHM_ROTATING_N_RESTART:
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/* Same a left_asymmetric, by first stripe is
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* D D D P Q rather than
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* Q D D D P
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*/
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pd = raid_disks - 1 - ((stripe + 1) % raid_disks);
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+1) % raid_disks;
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if (pd == raid_disks - 1)
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return block+1;
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if (block >= pd)
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return block+2;
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return block;
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case 600 + ALGORITHM_ROTATING_N_CONTINUE:
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/* Same as left_symmetric but Q is before P */
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pd = raid_disks - 1 - (stripe % raid_disks);
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if (block == -1)
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return pd;
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if (block == -2)
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return (pd+raid_disks-1) % raid_disks;
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return (pd + 1 + block) % raid_disks;
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}
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return -1;
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}
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int is_ddf(int layout)
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{
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switch (layout)
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{
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default:
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return 0;
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case ALGORITHM_ROTATING_N_CONTINUE:
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case ALGORITHM_ROTATING_N_RESTART:
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case ALGORITHM_ROTATING_ZERO_RESTART:
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return 1;
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}
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}
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void xor_blocks(char *target, char **sources, int disks, int size)
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{
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int i, j;
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/* Amazingly inefficient... */
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for (i=0; i<size; i++) {
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char c = 0;
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for (j=0 ; j<disks; j++)
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c ^= sources[j][i];
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target[i] = c;
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}
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}
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void qsyndrome(uint8_t *p, uint8_t *q, uint8_t **sources, int disks, int size)
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{
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int d, z;
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uint8_t wq0, wp0, wd0, w10, w20;
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for ( d = 0; d < size; d++) {
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wq0 = wp0 = sources[disks-1][d];
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for ( z = disks-2 ; z >= 0 ; z-- ) {
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wd0 = sources[z][d];
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wp0 ^= wd0;
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w20 = (wq0&0x80) ? 0xff : 0x00;
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w10 = (wq0 << 1) & 0xff;
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w20 &= 0x1d;
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w10 ^= w20;
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wq0 = w10 ^ wd0;
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}
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p[d] = wp0;
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q[d] = wq0;
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}
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}
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/*
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* The following was taken from linux/drivers/md/mktables.c, and modified
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* to create in-memory tables rather than C code
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*/
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static uint8_t gfmul(uint8_t a, uint8_t b)
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{
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uint8_t v = 0;
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while (b) {
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if (b & 1)
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v ^= a;
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a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
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b >>= 1;
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}
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return v;
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}
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static uint8_t gfpow(uint8_t a, int b)
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{
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uint8_t v = 1;
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b %= 255;
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if (b < 0)
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b += 255;
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while (b) {
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if (b & 1)
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v = gfmul(v, a);
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a = gfmul(a, a);
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b >>= 1;
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}
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return v;
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}
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int tables_ready = 0;
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uint8_t raid6_gfmul[256][256];
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uint8_t raid6_gfexp[256];
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uint8_t raid6_gfinv[256];
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uint8_t raid6_gfexi[256];
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uint8_t raid6_gflog[256];
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uint8_t raid6_gfilog[256];
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void make_tables(void)
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{
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int i, j;
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uint8_t v;
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uint32_t b, log;
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/* Compute multiplication table */
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for (i = 0; i < 256; i++)
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for (j = 0; j < 256; j++)
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raid6_gfmul[i][j] = gfmul(i, j);
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/* Compute power-of-2 table (exponent) */
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v = 1;
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for (i = 0; i < 256; i++) {
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raid6_gfexp[i] = v;
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v = gfmul(v, 2);
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if (v == 1)
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v = 0; /* For entry 255, not a real entry */
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}
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/* Compute inverse table x^-1 == x^254 */
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for (i = 0; i < 256; i++)
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raid6_gfinv[i] = gfpow(i, 254);
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/* Compute inv(2^x + 1) (exponent-xor-inverse) table */
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for (i = 0; i < 256; i ++)
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raid6_gfexi[i] = raid6_gfinv[raid6_gfexp[i] ^ 1];
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/* Compute log and inverse log */
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/* Modified code from:
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* https://web.eecs.utk.edu/~plank/plank/papers/CS-96-332.html
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*/
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b = 1;
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raid6_gflog[0] = 0;
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raid6_gfilog[255] = 0;
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for (log = 0; log < 255; log++) {
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raid6_gflog[b] = (uint8_t) log;
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raid6_gfilog[log] = (uint8_t) b;
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b = b << 1;
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if (b & 256) b = b ^ 0435;
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}
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tables_ready = 1;
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}
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uint8_t *zero;
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int zero_size;
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void ensure_zero_has_size(int chunk_size)
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{
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if (zero == NULL || chunk_size > zero_size) {
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if (zero)
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free(zero);
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zero = xcalloc(1, chunk_size);
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zero_size = chunk_size;
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}
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}
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/* Following was taken from linux/drivers/md/raid6recov.c */
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/* Recover two failed data blocks. */
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void raid6_2data_recov(int disks, size_t bytes, int faila, int failb,
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uint8_t **ptrs, int neg_offset)
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{
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uint8_t *p, *q, *dp, *dq;
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uint8_t px, qx, db;
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const uint8_t *pbmul; /* P multiplier table for B data */
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const uint8_t *qmul; /* Q multiplier table (for both) */
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if (faila > failb) {
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int t = faila;
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faila = failb;
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failb = t;
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}
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if (neg_offset) {
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p = ptrs[-1];
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q = ptrs[-2];
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} else {
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p = ptrs[disks-2];
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q = ptrs[disks-1];
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}
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/* Compute syndrome with zero for the missing data pages
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Use the dead data pages as temporary storage for
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delta p and delta q */
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dp = ptrs[faila];
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ptrs[faila] = zero;
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dq = ptrs[failb];
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ptrs[failb] = zero;
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qsyndrome(dp, dq, ptrs, disks-2, bytes);
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/* Restore pointer table */
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ptrs[faila] = dp;
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ptrs[failb] = dq;
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/* Now, pick the proper data tables */
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pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
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qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];
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/* Now do it... */
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while ( bytes-- ) {
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px = *p ^ *dp;
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qx = qmul[*q ^ *dq];
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*dq++ = db = pbmul[px] ^ qx; /* Reconstructed B */
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*dp++ = db ^ px; /* Reconstructed A */
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p++; q++;
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}
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}
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/* Recover failure of one data block plus the P block */
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void raid6_datap_recov(int disks, size_t bytes, int faila, uint8_t **ptrs,
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int neg_offset)
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{
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uint8_t *p, *q, *dq;
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const uint8_t *qmul; /* Q multiplier table */
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if (neg_offset) {
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p = ptrs[-1];
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q = ptrs[-2];
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} else {
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p = ptrs[disks-2];
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q = ptrs[disks-1];
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}
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/* Compute syndrome with zero for the missing data page
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Use the dead data page as temporary storage for delta q */
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dq = ptrs[faila];
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ptrs[faila] = zero;
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qsyndrome(p, dq, ptrs, disks-2, bytes);
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/* Restore pointer table */
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ptrs[faila] = dq;
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/* Now, pick the proper data tables */
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qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];
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/* Now do it... */
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while ( bytes-- ) {
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*p++ ^= *dq = qmul[*q ^ *dq];
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q++; dq++;
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}
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}
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/* Try to find out if a specific disk has a problem */
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int raid6_check_disks(int data_disks, int start, int chunk_size,
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int level, int layout, int diskP, int diskQ,
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uint8_t *p, uint8_t *q, char **stripes)
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{
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int i;
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int data_id, diskD;
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uint8_t Px, Qx;
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int curr_broken_disk = -1;
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int prev_broken_disk = -1;
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int broken_status = 0;
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for(i = 0; i < chunk_size; i++) {
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Px = (uint8_t)stripes[diskP][i] ^ (uint8_t)p[i];
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Qx = (uint8_t)stripes[diskQ][i] ^ (uint8_t)q[i];
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if((Px != 0) && (Qx == 0))
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curr_broken_disk = diskP;
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if((Px == 0) && (Qx != 0))
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curr_broken_disk = diskQ;
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if((Px != 0) && (Qx != 0)) {
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data_id = (raid6_gflog[Qx] - raid6_gflog[Px]);
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if(data_id < 0) data_id += 255;
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diskD = geo_map(data_id, start/chunk_size,
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data_disks + 2, level, layout);
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curr_broken_disk = diskD;
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}
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if((Px == 0) && (Qx == 0))
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curr_broken_disk = prev_broken_disk;
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if(curr_broken_disk >= data_disks + 2)
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broken_status = 2;
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switch(broken_status) {
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case 0:
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if(curr_broken_disk != -1) {
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prev_broken_disk = curr_broken_disk;
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broken_status = 1;
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}
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break;
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case 1:
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if(curr_broken_disk != prev_broken_disk)
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broken_status = 2;
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break;
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case 2:
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default:
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curr_broken_disk = prev_broken_disk = -2;
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break;
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}
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}
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return curr_broken_disk;
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}
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/*******************************************************************************
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* Function: save_stripes
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* Description:
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* Function reads data (only data without P and Q) from array and writes
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* it to buf and opcjonaly to backup files
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* Parameters:
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* source : A list of 'fds' of the active disks.
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* Some may be absent
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* offsets : A list of offsets on disk belonging
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* to the array [bytes]
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* raid_disks : geometry: number of disks in the array
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* chunk_size : geometry: chunk size [bytes]
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|
* 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 */
|