/*	$NetBSD: rf_decluster.h,v 1.7 2006/04/26 17:08:48 oster Exp $	*/
/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Mark Holland
 *
 * 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.
 */

/*----------------------------------------------------------------------
 *
 * decluster.h -- header file for declustered layout code
 *
 * Adapted from raidSim version July 1994
 * Created 10-21-92 (MCH)
 *
 *--------------------------------------------------------------------*/

#ifndef _RF__RF_DECLUSTER_H_
#define _RF__RF_DECLUSTER_H_

#include <dev/raidframe/raidframevar.h>

/*
 * These structures define the tables used to locate the spare unit
 * associated with a particular data or parity unit, and to perform
 * the associated inverse mapping.
 */

/* this is the layout-specific info structure for the declustered layout.
 */
struct RF_DeclusteredConfigInfo_s {
	RF_StripeCount_t groupSize;	/* no. of stripe units per parity
					 * stripe */
	RF_RowCol_t **LayoutTable;	/* the block design table */
	RF_RowCol_t **OffsetTable;	/* the sector offset table */
	RF_RowCol_t **BlockTable;	/* the block membership table */
	RF_StripeCount_t SUsPerFullTable;	/* stripe units per full table */
	RF_StripeCount_t SUsPerTable;	/* stripe units per table */
	RF_StripeCount_t PUsPerBlock;	/* parity units per block */
	RF_StripeCount_t SUsPerBlock;	/* stripe units per block */
	RF_StripeCount_t BlocksPerTable;	/* block design tuples per
						 * table */
	RF_StripeCount_t NumParityReps;	/* tables per full table */
	RF_StripeCount_t TableDepthInPUs;	/* PUs on one disk in 1 table */
	RF_StripeCount_t FullTableDepthInPUs;	/* PUs on one disk in 1
						 * fulltable */
	RF_StripeCount_t FullTableLimitSUID;	/* SU where partial fulltables
						 * start */
	RF_StripeCount_t ExtraTablesPerDisk;	/* # of tables in last
						 * fulltable */
	RF_SectorNum_t DiskOffsetOfLastFullTableInSUs;	/* disk offs of partial
							 * ft, if any */
	RF_StripeCount_t numCompleteFullTablesPerDisk;	/* ft identifier of
							 * partial ft, if any */
	u_int   Lambda;		/* the pair count in the block design */

	/* these are used only in the distributed-sparing case */
	RF_StripeCount_t FullTablesPerSpareRegion;	/* # of ft's comprising
							 * 1 spare region */
	RF_StripeCount_t TablesPerSpareRegion;	/* # of tables */
	RF_SectorCount_t SpareSpaceDepthPerRegionInSUs;	/* spare
							 * space/disk/region */
	RF_SectorCount_t SpareRegionDepthInSUs;	/* # of units/disk/region */
	RF_SectorNum_t DiskOffsetOfLastSpareSpaceChunkInSUs;	/* locates sp space
								 * after partial ft */
	RF_StripeCount_t TotSparePUsPerDisk;	/* total number of spare PUs
						 * per disk */
	RF_StripeCount_t NumCompleteSRs;
	RF_SpareTableEntry_t **SpareTable;	/* remap table for spare space */
	char    sparemap_fname[RF_SPAREMAP_NAME_LEN];	/* where to find
							 * sparemap. not used in
							 * kernel */
};

int
rf_ConfigureDeclustered(RF_ShutdownList_t ** listp, RF_Raid_t * raidPtr,
    RF_Config_t * cfgPtr);
int
rf_ConfigureDeclusteredDS(RF_ShutdownList_t ** listp, RF_Raid_t * raidPtr,
    RF_Config_t * cfgPtr);

void
rf_MapSectorDeclustered(RF_Raid_t * raidPtr, RF_RaidAddr_t raidSector,
    RF_RowCol_t * col, RF_SectorNum_t * diskSector, int remap);
void
rf_MapParityDeclustered(RF_Raid_t * raidPtr, RF_RaidAddr_t raidSector,
    RF_RowCol_t * col, RF_SectorNum_t * diskSector, int remap);
void
rf_IdentifyStripeDeclustered(RF_Raid_t * raidPtr, RF_RaidAddr_t addr,
    RF_RowCol_t ** diskids);
void
rf_MapSIDToPSIDDeclustered(RF_RaidLayout_t * layoutPtr,
    RF_StripeNum_t stripeID, RF_StripeNum_t * psID,
    RF_ReconUnitNum_t * which_ru);
int     rf_InstallSpareTable(RF_Raid_t * raidPtr, RF_RowCol_t frow, RF_RowCol_t fcol);
void    rf_FreeSpareTable(RF_Raid_t * raidPtr);

RF_HeadSepLimit_t rf_GetDefaultHeadSepLimitDeclustered(RF_Raid_t * raidPtr);
int     rf_GetDefaultNumFloatingReconBuffersDeclustered(RF_Raid_t * raidPtr);

void
rf_decluster_adjust_params(RF_RaidLayout_t * layoutPtr,
    RF_StripeNum_t * SUID, RF_StripeCount_t * sus_per_fulltable,
    RF_StripeCount_t * fulltable_depth, RF_StripeNum_t * base_suid);
void
rf_remap_to_spare_space(
    RF_RaidLayout_t * layoutPtr,
    RF_DeclusteredConfigInfo_t * info, RF_StripeNum_t FullTableID,
    RF_StripeNum_t TableID, RF_SectorNum_t BlockID, RF_StripeNum_t base_suid,
    RF_StripeNum_t SpareRegion, RF_RowCol_t * outCol, RF_StripeNum_t * outSU);
int     rf_SetSpareTable(RF_Raid_t * raidPtr, void *data);
RF_ReconUnitCount_t rf_GetNumSpareRUsDeclustered(RF_Raid_t * raidPtr);

#endif				/* !_RF__RF_DECLUSTER_H_ */