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/* $OpenBSD: rf_interdecluster.c,v 1.3 2000/01/11 18:02:22 peter Exp $ */
/* $NetBSD: rf_interdecluster.c,v 1.4 2000/01/07 03:41:00 oster Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Khalil Amiri
*
* 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_interdecluster.c -- implements interleaved declustering
*
************************************************************/
#include "rf_types.h"
#include "rf_raid.h"
#include "rf_interdecluster.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_general.h"
#include "rf_utils.h"
#include "rf_dagffrd.h"
#include "rf_dagdegrd.h"
#include "rf_dagffwr.h"
#include "rf_dagdegwr.h"
typedef struct RF_InterdeclusterConfigInfo_s {
RF_RowCol_t **stripeIdentifier; /* filled in at config time and used
* by IdentifyStripe */
RF_StripeCount_t numSparingRegions;
RF_StripeCount_t stripeUnitsPerSparingRegion;
RF_SectorNum_t mirrorStripeOffset;
} RF_InterdeclusterConfigInfo_t;
int
rf_ConfigureInterDecluster(
RF_ShutdownList_t ** listp,
RF_Raid_t * raidPtr,
RF_Config_t * cfgPtr)
{
RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
RF_StripeCount_t num_used_stripeUnitsPerDisk;
RF_InterdeclusterConfigInfo_t *info;
RF_RowCol_t i, tmp, SUs_per_region;
/* create an Interleaved Declustering configuration structure */
RF_MallocAndAdd(info, sizeof(RF_InterdeclusterConfigInfo_t), (RF_InterdeclusterConfigInfo_t *),
raidPtr->cleanupList);
if (info == NULL)
return (ENOMEM);
layoutPtr->layoutSpecificInfo = (void *) info;
/* fill in the config structure. */
SUs_per_region = raidPtr->numCol * (raidPtr->numCol - 1);
info->stripeIdentifier = rf_make_2d_array(SUs_per_region, 2, raidPtr->cleanupList);
if (info->stripeIdentifier == NULL)
return (ENOMEM);
for (i = 0; i < SUs_per_region; i++) {
info->stripeIdentifier[i][0] = i / (raidPtr->numCol - 1);
tmp = i / raidPtr->numCol;
info->stripeIdentifier[i][1] = (i + 1 + tmp) % raidPtr->numCol;
}
/* no spare tables */
RF_ASSERT(raidPtr->numRow == 1);
/* fill in the remaining layout parameters */
/* total number of stripes should a multiple of 2*numCol: Each sparing
* region consists of 2*numCol stripes: n-1 primary copy, n-1
* secondary copy and 2 for spare .. */
num_used_stripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk - (layoutPtr->stripeUnitsPerDisk %
(2 * raidPtr->numCol));
info->numSparingRegions = num_used_stripeUnitsPerDisk / (2 * raidPtr->numCol);
/* this is in fact the number of stripe units (that are primary data
* copies) in the sparing region */
info->stripeUnitsPerSparingRegion = raidPtr->numCol * (raidPtr->numCol - 1);
info->mirrorStripeOffset = info->numSparingRegions * (raidPtr->numCol + 1);
layoutPtr->numStripe = info->numSparingRegions * info->stripeUnitsPerSparingRegion;
layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector;
layoutPtr->numDataCol = 1;
layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
layoutPtr->numParityCol = 1;
layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk;
raidPtr->sectorsPerDisk =
num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit;
raidPtr->totalSectors =
(layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit;
layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk / layoutPtr->sectorsPerStripeUnit;
return (0);
}
int
rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t * raidPtr)
{
return (30);
}
RF_HeadSepLimit_t
rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t * raidPtr)
{
return (raidPtr->sectorsPerDisk);
}
RF_ReconUnitCount_t
rf_GetNumSpareRUsInterDecluster(
RF_Raid_t * raidPtr)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions));
/* the layout uses two stripe units per disk as spare within each
* sparing region */
}
/* Maps to the primary copy of the data, i.e. the first mirror pair */
void
rf_MapSectorInterDecluster(
RF_Raid_t * raidPtr,
RF_RaidAddr_t raidSector,
RF_RowCol_t * row,
RF_RowCol_t * col,
RF_SectorNum_t * diskSector,
int remap)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk;
RF_StripeNum_t sparing_region_id, index_within_region;
int col_before_remap;
*row = 0;
sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
index_within_region = SUID % info->stripeUnitsPerSparingRegion;
su_offset_into_disk = index_within_region % (raidPtr->numCol - 1);
mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
col_before_remap = index_within_region / (raidPtr->numCol - 1);
if (!remap) {
*col = col_before_remap;;
*diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) * sparing_region_id)) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
} else {
/* remap sector to spare space... */
*diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
*col = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol;
*col = (*col + 1) % raidPtr->numCol;
if (*col == col_before_remap)
*col = (*col + 1) % raidPtr->numCol;
}
}
/* Maps to the second copy of the mirror pair. */
void
rf_MapParityInterDecluster(
RF_Raid_t * raidPtr,
RF_RaidAddr_t raidSector,
RF_RowCol_t * row,
RF_RowCol_t * col,
RF_SectorNum_t * diskSector,
int remap)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t sparing_region_id, index_within_region, mirror_su_offset_into_disk;
RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
int col_before_remap;
sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
index_within_region = SUID % info->stripeUnitsPerSparingRegion;
mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
col_before_remap = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol;
*row = 0;
if (!remap) {
*col = col_before_remap;
*diskSector = info->mirrorStripeOffset * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += sparing_region_id * (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += mirror_su_offset_into_disk * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
} else {
/* remap parity to spare space ... */
*diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidPtr->numCol) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
*col = index_within_region / (raidPtr->numCol - 1);
*col = (*col + 1) % raidPtr->numCol;
if (*col == col_before_remap)
*col = (*col + 1) % raidPtr->numCol;
}
}
void
rf_IdentifyStripeInterDecluster(
RF_Raid_t * raidPtr,
RF_RaidAddr_t addr,
RF_RowCol_t ** diskids,
RF_RowCol_t * outRow)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t SUID;
SUID = addr / raidPtr->Layout.sectorsPerStripeUnit;
SUID = SUID % info->stripeUnitsPerSparingRegion;
*outRow = 0;
*diskids = info->stripeIdentifier[SUID];
}
void
rf_MapSIDToPSIDInterDecluster(
RF_RaidLayout_t * layoutPtr,
RF_StripeNum_t stripeID,
RF_StripeNum_t * psID,
RF_ReconUnitNum_t * which_ru)
{
*which_ru = 0;
*psID = stripeID;
}
/******************************************************************************
* select a graph to perform a single-stripe access
*
* Parameters: raidPtr - description of the physical array
* type - type of operation (read or write) requested
* asmap - logical & physical addresses for this access
* createFunc - name of function to use to create the graph
*****************************************************************************/
void
rf_RAIDIDagSelect(
RF_Raid_t * raidPtr,
RF_IoType_t type,
RF_AccessStripeMap_t * asmap,
RF_VoidFuncPtr * createFunc)
{
RF_ASSERT(RF_IO_IS_R_OR_W(type));
if (asmap->numDataFailed + asmap->numParityFailed > 1) {
RF_ERRORMSG("Multiple disks failed in a single group! Aborting I/O operation.\n");
*createFunc = NULL;
return;
}
*createFunc = (type == RF_IO_TYPE_READ) ? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG : (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
if (type == RF_IO_TYPE_READ) {
if (asmap->numDataFailed == 0)
*createFunc = (RF_VoidFuncPtr) rf_CreateMirrorPartitionReadDAG;
else
*createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneDegradedReadDAG;
} else
*createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
}
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