NetBSD/sys/dev/raidframe/rf_raid5.c

403 lines
13 KiB
C

/* $NetBSD: rf_raid5.c,v 1.1 1998/11/13 04:20:33 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.
*/
/******************************************************************************
*
* rf_raid5.c -- implements RAID Level 5
*
*****************************************************************************/
/*
* :
* Log: rf_raid5.c,v
* Revision 1.26 1996/11/05 21:10:40 jimz
* failed pda generalization
*
* Revision 1.25 1996/07/31 16:56:18 jimz
* dataBytesPerStripe, sectorsPerDisk init arch-indep.
*
* Revision 1.24 1996/07/18 22:57:14 jimz
* port simulator to AIX
*
* Revision 1.23 1996/07/13 00:00:59 jimz
* sanitized generalized reconstruction architecture
* cleaned up head sep, rbuf problems
*
* Revision 1.22 1996/06/11 08:54:27 jimz
* improved error-checking at configuration time
*
* Revision 1.21 1996/06/10 11:55:47 jimz
* Straightened out some per-array/not-per-array distinctions, fixed
* a couple bugs related to confusion. Added shutdown lists. Removed
* layout shutdown function (now subsumed by shutdown lists).
*
* Revision 1.20 1996/06/07 22:26:27 jimz
* type-ify which_ru (RF_ReconUnitNum_t)
*
* Revision 1.19 1996/06/07 21:33:04 jimz
* begin using consistent types for sector numbers,
* stripe numbers, row+col numbers, recon unit numbers
*
* Revision 1.18 1996/06/05 18:06:02 jimz
* Major code cleanup. The Great Renaming is now done.
* Better modularity. Better typing. Fixed a bunch of
* synchronization bugs. Made a lot of global stuff
* per-desc or per-array. Removed dead code.
*
* Revision 1.17 1996/06/03 23:28:26 jimz
* more bugfixes
* check in tree to sync for IPDS runs with current bugfixes
* there still may be a problem with threads in the script test
* getting I/Os stuck- not trivially reproducible (runs ~50 times
* in a row without getting stuck)
*
* Revision 1.16 1996/06/02 17:31:48 jimz
* Moved a lot of global stuff into array structure, where it belongs.
* Fixed up paritylogging, pss modules in this manner. Some general
* code cleanup. Removed lots of dead code, some dead files.
*
* Revision 1.15 1996/05/31 22:26:54 jimz
* fix a lot of mapping problems, memory allocation problems
* found some weird lock issues, fixed 'em
* more code cleanup
*
* Revision 1.14 1996/05/30 23:22:16 jimz
* bugfixes of serialization, timing problems
* more cleanup
*
* Revision 1.13 1996/05/27 18:56:37 jimz
* more code cleanup
* better typing
* compiles in all 3 environments
*
* Revision 1.12 1996/05/24 22:17:04 jimz
* continue code + namespace cleanup
* typed a bunch of flags
*
* Revision 1.11 1996/05/24 01:59:45 jimz
* another checkpoint in code cleanup for release
* time to sync kernel tree
*
* Revision 1.10 1996/05/23 00:33:23 jimz
* code cleanup: move all debug decls to rf_options.c, all extern
* debug decls to rf_options.h, all debug vars preceded by rf_
*
* Revision 1.9 1996/05/18 19:51:34 jimz
* major code cleanup- fix syntax, make some types consistent,
* add prototypes, clean out dead code, et cetera
*
* Revision 1.8 1996/05/03 19:38:58 wvcii
* moved dag creation routines to dag library
*
* Revision 1.7 1995/12/12 18:10:06 jimz
* MIN -> RF_MIN, MAX -> RF_MAX, ASSERT -> RF_ASSERT
* fix 80-column brain damage in comments
*
* Revision 1.6 1995/12/06 15:04:28 root
* added copyright info
*
* Revision 1.5 1995/11/17 18:59:41 wvcii
* added prototyping to MapParity
*
* Revision 1.4 1995/06/23 13:38:21 robby
* updeated to prototypes in rf_layout.h
*
*/
#include "rf_types.h"
#include "rf_raid.h"
#include "rf_raid5.h"
#include "rf_dag.h"
#include "rf_dagffrd.h"
#include "rf_dagffwr.h"
#include "rf_dagdegrd.h"
#include "rf_dagdegwr.h"
#include "rf_dagutils.h"
#include "rf_threadid.h"
#include "rf_general.h"
#include "rf_map.h"
#include "rf_utils.h"
typedef struct RF_Raid5ConfigInfo_s {
RF_RowCol_t **stripeIdentifier; /* filled in at config time and used by IdentifyStripe */
} RF_Raid5ConfigInfo_t;
int rf_ConfigureRAID5(
RF_ShutdownList_t **listp,
RF_Raid_t *raidPtr,
RF_Config_t *cfgPtr)
{
RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
RF_Raid5ConfigInfo_t *info;
RF_RowCol_t i, j, startdisk;
/* create a RAID level 5 configuration structure */
RF_MallocAndAdd(info, sizeof(RF_Raid5ConfigInfo_t), (RF_Raid5ConfigInfo_t *), raidPtr->cleanupList);
if (info == NULL)
return(ENOMEM);
layoutPtr->layoutSpecificInfo = (void *) info;
RF_ASSERT(raidPtr->numRow == 1);
/* the stripe identifier must identify the disks in each stripe,
* IN THE ORDER THAT THEY APPEAR IN THE STRIPE.
*/
info->stripeIdentifier = rf_make_2d_array(raidPtr->numCol, raidPtr->numCol, raidPtr->cleanupList);
if (info->stripeIdentifier == NULL)
return(ENOMEM);
startdisk = 0;
for (i=0; i<raidPtr->numCol; i++) {
for (j=0; j<raidPtr->numCol; j++) {
info->stripeIdentifier[i][j] = (startdisk + j) % raidPtr->numCol;
}
if ((--startdisk) < 0) startdisk = raidPtr->numCol-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;
layoutPtr->dataStripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk;
raidPtr->totalSectors = layoutPtr->stripeUnitsPerDisk * layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
return(0);
}
int rf_GetDefaultNumFloatingReconBuffersRAID5(RF_Raid_t *raidPtr)
{
return(20);
}
RF_HeadSepLimit_t rf_GetDefaultHeadSepLimitRAID5(RF_Raid_t *raidPtr)
{
return(10);
}
#if !defined(__NetBSD__) && !defined(_KERNEL)
/* not currently used */
int rf_ShutdownRAID5(RF_Raid_t *raidPtr)
{
return(0);
}
#endif
void rf_MapSectorRAID5(
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->numCol);
*diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
(raidSector % raidPtr->Layout.sectorsPerStripeUnit);
}
void rf_MapParityRAID5(
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-(SUID/raidPtr->Layout.numDataCol)%raidPtr->numCol;
*diskSector =(SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
(raidSector % raidPtr->Layout.sectorsPerStripeUnit);
}
void rf_IdentifyStripeRAID5(
RF_Raid_t *raidPtr,
RF_RaidAddr_t addr,
RF_RowCol_t **diskids,
RF_RowCol_t *outRow)
{
RF_StripeNum_t stripeID = rf_RaidAddressToStripeID(&raidPtr->Layout, addr);
RF_Raid5ConfigInfo_t *info = (RF_Raid5ConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
*outRow = 0;
*diskids = info->stripeIdentifier[ stripeID % raidPtr->numCol ];
}
void rf_MapSIDToPSIDRAID5(
RF_RaidLayout_t *layoutPtr,
RF_StripeNum_t stripeID,
RF_StripeNum_t *psID,
RF_ReconUnitNum_t *which_ru)
{
*which_ru = 0;
*psID = stripeID;
}
/* select an algorithm for performing an access. Returns two pointers,
* one to a function that will return information about the DAG, and
* another to a function that will create the dag.
*/
void rf_RaidFiveDagSelect(
RF_Raid_t *raidPtr,
RF_IoType_t type,
RF_AccessStripeMap_t *asmap,
RF_VoidFuncPtr *createFunc)
{
RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
RF_PhysDiskAddr_t *failedPDA=NULL;
RF_RowCol_t frow, fcol;
RF_RowStatus_t rstat;
int prior_recon;
int tid;
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");
/* *infoFunc = */ *createFunc = NULL;
return;
} else if (asmap->numDataFailed + asmap->numParityFailed == 1) {
/* if under recon & already reconstructed, redirect the access to the spare drive
* and eliminate the failure indication
*/
failedPDA = asmap->failedPDAs[0];
frow = failedPDA->row; fcol = failedPDA->col;
rstat = raidPtr->status[failedPDA->row];
prior_recon = (rstat == rf_rs_reconfigured) || (
(rstat == rf_rs_reconstructing) ?
rf_CheckRUReconstructed(raidPtr->reconControl[frow]->reconMap, failedPDA->startSector) : 0
);
if (prior_recon) {
RF_RowCol_t or = failedPDA->row,oc=failedPDA->col;
RF_SectorNum_t oo=failedPDA->startSector;
if (layoutPtr->map->flags & RF_DISTRIBUTE_SPARE) { /* redirect to dist spare space */
if (failedPDA == asmap->parityInfo) {
/* parity has failed */
(layoutPtr->map->MapParity)(raidPtr, failedPDA->raidAddress, &failedPDA->row,
&failedPDA->col, &failedPDA->startSector, RF_REMAP);
if (asmap->parityInfo->next) { /* redir 2nd component, if any */
RF_PhysDiskAddr_t *p = asmap->parityInfo->next;
RF_SectorNum_t SUoffs = p->startSector % layoutPtr->sectorsPerStripeUnit;
p->row = failedPDA->row;
p->col = failedPDA->col;
p->startSector = rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, failedPDA->startSector) +
SUoffs; /* cheating: startSector is not really a RAID address */
}
} else if (asmap->parityInfo->next && failedPDA == asmap->parityInfo->next) {
RF_ASSERT(0); /* should not ever happen */
} else {
/* data has failed */
(layoutPtr->map->MapSector)(raidPtr, failedPDA->raidAddress, &failedPDA->row,
&failedPDA->col, &failedPDA->startSector, RF_REMAP);
}
} else { /* redirect to dedicated spare space */
failedPDA->row = raidPtr->Disks[frow][fcol].spareRow;
failedPDA->col = raidPtr->Disks[frow][fcol].spareCol;
/* the parity may have two distinct components, both of which may need to be redirected */
if (asmap->parityInfo->next) {
if (failedPDA == asmap->parityInfo) {
failedPDA->next->row = failedPDA->row;
failedPDA->next->col = failedPDA->col;
} else if (failedPDA == asmap->parityInfo->next) { /* paranoid: should never occur */
asmap->parityInfo->row = failedPDA->row;
asmap->parityInfo->col = failedPDA->col;
}
}
}
RF_ASSERT(failedPDA->col != -1);
if (rf_dagDebug || rf_mapDebug) {
rf_get_threadid(tid);
printf("[%d] Redirected type '%c' r %d c %d o %ld -> r %d c %d o %ld\n",
tid,type,or,oc,(long)oo,failedPDA->row,failedPDA->col,
(long)failedPDA->startSector);
}
asmap->numDataFailed = asmap->numParityFailed = 0;
}
}
/* all dags begin/end with block/unblock node
* therefore, hdrSucc & termAnt counts should always be 1
* also, these counts should not be visible outside dag creation routines -
* manipulating the counts here should be removed */
if (type == RF_IO_TYPE_READ) {
if (asmap->numDataFailed == 0)
*createFunc = (RF_VoidFuncPtr)rf_CreateFaultFreeReadDAG;
else
*createFunc = (RF_VoidFuncPtr)rf_CreateRaidFiveDegradedReadDAG;
} else {
/* if mirroring, always use large writes. If the access requires two
* distinct parity updates, always do a small write. If the stripe
* contains a failure but the access does not, do a small write.
* The first conditional (numStripeUnitsAccessed <= numDataCol/2) uses a
* less-than-or-equal rather than just a less-than because when G is 3
* or 4, numDataCol/2 is 1, and I want single-stripe-unit updates to use
* just one disk.
*/
if ( (asmap->numDataFailed + asmap->numParityFailed) == 0) {
if (rf_suppressLocksAndLargeWrites ||
(((asmap->numStripeUnitsAccessed <= (layoutPtr->numDataCol / 2)) && (layoutPtr->numDataCol!=1)) ||
(asmap->parityInfo->next!=NULL) || rf_CheckStripeForFailures(raidPtr, asmap))) {
*createFunc = (RF_VoidFuncPtr)rf_CreateSmallWriteDAG;
}
else
*createFunc = (RF_VoidFuncPtr)rf_CreateLargeWriteDAG;
}
else {
if (asmap->numParityFailed == 1)
*createFunc = (RF_VoidFuncPtr)rf_CreateNonRedundantWriteDAG;
else
if (asmap->numStripeUnitsAccessed != 1 && failedPDA->numSector != layoutPtr->sectorsPerStripeUnit)
*createFunc = NULL;
else
*createFunc = (RF_VoidFuncPtr)rf_CreateDegradedWriteDAG;
}
}
}