/*      $NetBSD: rf_raid4.c,v 1.13 2019/02/09 03:34:00 christos 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  [email protected]
*  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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rf_raid4.c,v 1.13 2019/02/09 03:34:00 christos Exp $");

#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_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 ... */
       info = RF_MallocAndAdd(sizeof(*info), raidPtr->cleanupList);
       if (info == NULL)
               return (ENOMEM);
       layoutPtr->layoutSpecificInfo = (void *) info;

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

       /* fill in the remaining layout parameters */
       layoutPtr->numStripe = layoutPtr->stripeUnitsPerDisk;
       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 *col, RF_SectorNum_t *diskSector,
                 int remap)
{
       RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
       *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 *col, RF_SectorNum_t *diskSector,
                 int remap)
{
       RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;

       *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_Raid4ConfigInfo_t *info = raidPtr->Layout.layoutSpecificInfo;

       *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;
}