rf_evenodd_dags.c

RAIDFrame是个非常好的磁盘阵列RAID仿真工具

/*
 * rf_evenodd_dags.c
 */
/*
 * Copyright (c) 1996 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Chang-Ming Wu
 *
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  [e-mail]
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

#include "rf_archs.h"

#if RF_INCLUDE_EVENODD > 0

#include "rf_types.h"
#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_dagfuncs.h"
#include "rf_dagutils.h"
#include "rf_etimer.h"
#include "rf_acctrace.h"
#include "rf_general.h"
#include "rf_evenodd_dags.h"
#include "rf_evenodd.h"
#include "rf_evenodd_dagfuncs.h"
#include "rf_pq.h"

/*
 * Lost one data.
 * Use P to reconstruct missing data.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_100_CreateReadDAG)
{
  rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_eoPRecoveryFuncs);
}

/*
 * Lost data + E.
 * Use P to reconstruct missing data.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_101_CreateReadDAG)
{
  rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_eoPRecoveryFuncs);
}

/*
 * Lost data + P.
 * Make E look like P, and use Eor for Xor, and we can
 * use degraded read DAG.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_110_CreateReadDAG)
{
  RF_PhysDiskAddr_t *temp;
  /* swap P and E pointers to fake out the DegradedReadDAG code */
  temp = asmap->parityInfo; asmap->parityInfo = asmap->qInfo; asmap->qInfo = temp;
  rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_eoERecoveryFuncs);
}

/*
 * Lost two data.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EOCreateDoubleDegradedReadDAG)
{
  rf_EO_DoubleDegRead(raidPtr, asmap, dag_h, bp, flags, allocList);
}

/*
 * Lost two data.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_200_CreateReadDAG)
{
  rf_EOCreateDoubleDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList);
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_100_CreateWriteDAG)
{
  if (asmap->numStripeUnitsAccessed != 1 && 
      asmap->failedPDA->numSector != raidPtr->Layout.sectorsPerStripeUnit) 
    RF_PANIC();
  rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, 2, (int (*)())rf_Degraded_100_EOFunc, RF_TRUE);
}

/*
 * E is dead. Small write.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_001_CreateSmallWriteDAG)
{
  rf_CommonCreateSmallWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_EOSmallWritePFuncs, NULL);
}

/*
 * E is dead. Large write.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_001_CreateLargeWriteDAG)
{
  rf_CommonCreateLargeWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, 1, rf_RegularPFunc, RF_TRUE);
}

/*
 * P is dead. Small write.
 * Swap E + P, use single-degraded stuff.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_010_CreateSmallWriteDAG)
{
  RF_PhysDiskAddr_t *temp;
  /* swap P and E pointers to fake out the DegradedReadDAG code */
  temp = asmap->parityInfo; asmap->parityInfo = asmap->qInfo; asmap->qInfo = temp;
  rf_CommonCreateSmallWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_EOSmallWriteEFuncs, NULL);
}

/*
 * P is dead. Large write.
 * Swap E + P, use single-degraded stuff.
 */
RF_CREATE_DAG_FUNC_DECL(rf_EO_010_CreateLargeWriteDAG)
{
  RF_PhysDiskAddr_t *temp;
  /* swap P and E pointers to fake out the code */
  temp = asmap->parityInfo; asmap->parityInfo = asmap->qInfo; asmap->qInfo = temp;
  rf_CommonCreateLargeWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, 1, rf_RegularEFunc, RF_FALSE);
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_011_CreateWriteDAG)
{
  rf_CreateNonRedundantWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
    RF_IO_TYPE_WRITE);
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_110_CreateWriteDAG)
{
  RF_PhysDiskAddr_t *temp;

  if (asmap->numStripeUnitsAccessed != 1 && 
      asmap->failedPDA->numSector != raidPtr->Layout.sectorsPerStripeUnit)
  {
    RF_PANIC();
  }
  /* swap P and E to fake out parity code */
  temp = asmap->parityInfo; asmap->parityInfo = asmap->qInfo; asmap->qInfo = temp;
  rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList,1, (int (*)())rf_EO_DegradedWriteEFunc, RF_FALSE); 
  /* is the regular E func the right one to call? */
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_101_CreateWriteDAG)
{
  if (asmap->numStripeUnitsAccessed != 1 && 
      asmap->failedPDA->numSector != raidPtr->Layout.sectorsPerStripeUnit)
    RF_PANIC();
  rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList,1, rf_RecoveryXorFunc, RF_TRUE);
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_DoubleDegRead)
{
  rf_DoubleDegRead(raidPtr, asmap, dag_h, bp, flags, allocList,
    "Re", "EvenOddRecovery", rf_EvenOddDoubleRecoveryFunc);
}
  
RF_CREATE_DAG_FUNC_DECL(rf_EOCreateSmallWriteDAG)
{
  rf_CommonCreateSmallWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_pFuncs, &rf_EOSmallWriteEFuncs);
}

RF_CREATE_DAG_FUNC_DECL(rf_EOCreateLargeWriteDAG)
{
  rf_CommonCreateLargeWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList, 2, rf_RegularPEFunc, RF_FALSE);
}

RF_CREATE_DAG_FUNC_DECL(rf_EO_200_CreateWriteDAG)
{
  rf_DoubleDegSmallWrite(raidPtr, asmap, dag_h, bp, flags, allocList, "Re", "We", "EOWrDDRecovery", rf_EOWriteDoubleRecoveryFunc);
}

#endif /* RF_INCLUDE_EVENODD > 0 */