NetBSD/sys/dev/raidframe/rf_raid4.c

/*	$NetBSD: rf_raid4.c,v 1.2 1999/01/26 02:34:00 oster Exp $	*/
/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Rachad Youssef
 *
 * 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  Software.Distribution@CS.CMU.EDU
 *  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.
 */

/***************************************
 *
 * rf_raid4.c -- implements RAID Level 4
 *
 ***************************************/

#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_dagffrd.h"
#include "rf_dagffwr.h"
#include "rf_dagdegrd.h"
#include "rf_dagdegwr.h"
#include "rf_threadid.h"
#include "rf_raid4.h"
#include "rf_general.h"

typedef struct RF_Raid4ConfigInfo_s {
  RF_RowCol_t  *stripeIdentifier;               /* filled in at config time & used by IdentifyStripe */
} RF_Raid4ConfigInfo_t;



int rf_ConfigureRAID4(
  RF_ShutdownList_t  **listp,
  RF_Raid_t           *raidPtr,
  RF_Config_t         *cfgPtr)
{
  RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
  RF_Raid4ConfigInfo_t *info;
  int i;

  /* create a RAID level 4 configuration structure ... */
  RF_MallocAndAdd(info, sizeof(RF_Raid4ConfigInfo_t), (RF_Raid4ConfigInfo_t *), raidPtr->cleanupList);
  if (info == NULL)
    return(ENOMEM);
  layoutPtr->layoutSpecificInfo = (void *) info;

  /* ... and fill it in. */
  RF_MallocAndAdd(info->stripeIdentifier, raidPtr->numCol * sizeof(RF_RowCol_t), (RF_RowCol_t *), raidPtr->cleanupList);
  if (info->stripeIdentifier == NULL)
    return(ENOMEM);
  for (i=0; i<raidPtr->numCol; i++)
    info->stripeIdentifier[i] = i;

  RF_ASSERT(raidPtr->numRow == 1);

  /* fill in the remaining layout parameters */
  layoutPtr->numStripe = layoutPtr->stripeUnitsPerDisk;
  layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector;
  layoutPtr->numDataCol = raidPtr->numCol-1;
  layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
  layoutPtr->numParityCol = 1;
  raidPtr->totalSectors = layoutPtr->stripeUnitsPerDisk * layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;

  return(0);
}

int rf_GetDefaultNumFloatingReconBuffersRAID4(RF_Raid_t *raidPtr)
{
  return(20);
}

RF_HeadSepLimit_t rf_GetDefaultHeadSepLimitRAID4(RF_Raid_t *raidPtr)
{
  return(20);
}

void rf_MapSectorRAID4(
  RF_Raid_t         *raidPtr,
  RF_RaidAddr_t      raidSector,
  RF_RowCol_t       *row,
  RF_RowCol_t       *col,
  RF_SectorNum_t    *diskSector,
  int                remap)
{
  RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
  *row = 0;
  *col = SUID % raidPtr->Layout.numDataCol;
  *diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
    (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
}

void rf_MapParityRAID4(
  RF_Raid_t       *raidPtr,
  RF_RaidAddr_t    raidSector,
  RF_RowCol_t     *row,
  RF_RowCol_t     *col,
  RF_SectorNum_t  *diskSector,
  int              remap)
{
  RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
  
  *row = 0;
  *col = raidPtr->Layout.numDataCol;
  *diskSector =(SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
    (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
}

void rf_IdentifyStripeRAID4(
  RF_Raid_t        *raidPtr,
  RF_RaidAddr_t     addr,
  RF_RowCol_t     **diskids,
  RF_RowCol_t      *outRow)
{
  RF_Raid4ConfigInfo_t *info = raidPtr->Layout.layoutSpecificInfo;
  
  *outRow = 0;
  *diskids = info->stripeIdentifier;
}

void rf_MapSIDToPSIDRAID4(
  RF_RaidLayout_t    *layoutPtr,
  RF_StripeNum_t      stripeID,
  RF_StripeNum_t     *psID,
  RF_ReconUnitNum_t  *which_ru)
{
  *which_ru = 0;
  *psID = stripeID;
}