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author | David Woodhouse <David.Woodhouse@intel.com> | 2010-08-11 00:19:05 +0100 |
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committer | David Woodhouse <David.Woodhouse@intel.com> | 2010-08-11 00:19:05 +0100 |
commit | cc4589ebfae6f8dbb5cf880a0a67eedab3416492 (patch) | |
tree | 404335e6dec9d79351f537de58979a8b964e2b0c /lib/raid6/raid6recov.c | |
parent | 3d30701b58970425e1d45994d6cb82f828924fdd (diff) | |
download | op-kernel-dev-cc4589ebfae6f8dbb5cf880a0a67eedab3416492.zip op-kernel-dev-cc4589ebfae6f8dbb5cf880a0a67eedab3416492.tar.gz |
Rename raid6 files now they're in a 'raid6' directory.
Linus asks 'why "raid6" twice?'. No reason.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'lib/raid6/raid6recov.c')
-rw-r--r-- | lib/raid6/raid6recov.c | 132 |
1 files changed, 0 insertions, 132 deletions
diff --git a/lib/raid6/raid6recov.c b/lib/raid6/raid6recov.c deleted file mode 100644 index 2609f00..0000000 --- a/lib/raid6/raid6recov.c +++ /dev/null @@ -1,132 +0,0 @@ -/* -*- linux-c -*- ------------------------------------------------------- * - * - * Copyright 2002 H. Peter Anvin - All Rights Reserved - * - * 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, Inc., 53 Temple Place Ste 330, - * Boston MA 02111-1307, USA; either version 2 of the License, or - * (at your option) any later version; incorporated herein by reference. - * - * ----------------------------------------------------------------------- */ - -/* - * raid6recov.c - * - * RAID-6 data recovery in dual failure mode. In single failure mode, - * use the RAID-5 algorithm (or, in the case of Q failure, just reconstruct - * the syndrome.) - */ - -#include <linux/raid/pq.h> - -/* Recover two failed data blocks. */ -void raid6_2data_recov(int disks, size_t bytes, int faila, int failb, - void **ptrs) -{ - u8 *p, *q, *dp, *dq; - u8 px, qx, db; - const u8 *pbmul; /* P multiplier table for B data */ - const u8 *qmul; /* Q multiplier table (for both) */ - - p = (u8 *)ptrs[disks-2]; - q = (u8 *)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 = (u8 *)ptrs[faila]; - ptrs[faila] = (void *)raid6_empty_zero_page; - ptrs[disks-2] = dp; - dq = (u8 *)ptrs[failb]; - ptrs[failb] = (void *)raid6_empty_zero_page; - ptrs[disks-1] = dq; - - raid6_call.gen_syndrome(disks, bytes, ptrs); - - /* Restore pointer table */ - ptrs[faila] = dp; - ptrs[failb] = dq; - ptrs[disks-2] = p; - ptrs[disks-1] = q; - - /* 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++; - } -} -EXPORT_SYMBOL_GPL(raid6_2data_recov); - -/* Recover failure of one data block plus the P block */ -void raid6_datap_recov(int disks, size_t bytes, int faila, void **ptrs) -{ - u8 *p, *q, *dq; - const u8 *qmul; /* Q multiplier table */ - - p = (u8 *)ptrs[disks-2]; - q = (u8 *)ptrs[disks-1]; - - /* Compute syndrome with zero for the missing data page - Use the dead data page as temporary storage for delta q */ - dq = (u8 *)ptrs[faila]; - ptrs[faila] = (void *)raid6_empty_zero_page; - ptrs[disks-1] = dq; - - raid6_call.gen_syndrome(disks, bytes, ptrs); - - /* Restore pointer table */ - ptrs[faila] = dq; - ptrs[disks-1] = q; - - /* 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++; - } -} -EXPORT_SYMBOL_GPL(raid6_datap_recov); - -#ifndef __KERNEL__ -/* Testing only */ - -/* Recover two failed blocks. */ -void raid6_dual_recov(int disks, size_t bytes, int faila, int failb, void **ptrs) -{ - if ( faila > failb ) { - int tmp = faila; - faila = failb; - failb = tmp; - } - - if ( failb == disks-1 ) { - if ( faila == disks-2 ) { - /* P+Q failure. Just rebuild the syndrome. */ - raid6_call.gen_syndrome(disks, bytes, ptrs); - } else { - /* data+Q failure. Reconstruct data from P, - then rebuild syndrome. */ - /* NOT IMPLEMENTED - equivalent to RAID-5 */ - } - } else { - if ( failb == disks-2 ) { - /* data+P failure. */ - raid6_datap_recov(disks, bytes, faila, ptrs); - } else { - /* data+data failure. */ - raid6_2data_recov(disks, bytes, faila, failb, ptrs); - } - } -} - -#endif |