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/* $OpenBSD: rf_reconstruct.h,v 1.3 1999/07/30 14:45:33 peter Exp $ */
/* $NetBSD: rf_reconstruct.h,v 1.4 1999/03/02 03:18:48 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.
*/
/*********************************************************
* rf_reconstruct.h -- header file for reconstruction code
*********************************************************/
#ifndef _RF__RF_RECONSTRUCT_H_
#define _RF__RF_RECONSTRUCT_H_
#include "rf_types.h"
#include <sys/time.h>
#include "rf_reconmap.h"
#include "rf_psstatus.h"
/* reconstruction configuration information */
struct RF_ReconConfig_s {
unsigned numFloatingReconBufs; /* number of floating recon bufs to
* use */
RF_HeadSepLimit_t headSepLimit; /* how far apart the heads are allow
* to become, in parity stripes */
};
/* a reconstruction buffer */
struct RF_ReconBuffer_s {
RF_Raid_t *raidPtr; /* void * to avoid recursive includes */
caddr_t buffer; /* points to the data */
RF_StripeNum_t parityStripeID; /* the parity stripe that this data
* relates to */
int which_ru; /* which reconstruction unit within the PSS */
RF_SectorNum_t failedDiskSectorOffset; /* the offset into the failed
* disk */
RF_RowCol_t row, col; /* which disk this buffer belongs to or is
* targeted at */
RF_StripeCount_t count; /* counts the # of SUs installed so far */
int priority; /* used to force hi priority recon */
RF_RbufType_t type; /* FORCED or FLOATING */
char *arrived; /* [x] = 1/0 if SU from disk x has/hasn't
* arrived */
RF_ReconBuffer_t *next; /* used for buffer management */
void *arg; /* generic field for general use */
RF_RowCol_t spRow, spCol; /* spare disk to which this buf should
* be written */
/* if dist sparing off, always identifies the replacement disk */
RF_SectorNum_t spOffset;/* offset into the spare disk */
/* if dist sparing off, identical to failedDiskSectorOffset */
RF_ReconParityStripeStatus_t *pssPtr; /* debug- pss associated with
* issue-pending write */
};
/* a reconstruction event descriptor. The event types currently are:
* RF_REVENT_READDONE -- a read operation has completed
* RF_REVENT_WRITEDONE -- a write operation has completed
* RF_REVENT_BUFREADY -- the buffer manager has produced a full buffer
* RF_REVENT_BLOCKCLEAR -- a reconstruction blockage has been cleared
* RF_REVENT_BUFCLEAR -- the buffer manager has released a process blocked on submission
* RF_REVENT_SKIP -- we need to skip the current RU and go on to the next one, typ. b/c we found recon forced
* RF_REVENT_FORCEDREADONE- a forced-reconstructoin read operation has completed
*/
typedef enum RF_Revent_e {
RF_REVENT_READDONE,
RF_REVENT_WRITEDONE,
RF_REVENT_BUFREADY,
RF_REVENT_BLOCKCLEAR,
RF_REVENT_BUFCLEAR,
RF_REVENT_HEADSEPCLEAR,
RF_REVENT_SKIP,
RF_REVENT_FORCEDREADDONE
} RF_Revent_t;
struct RF_ReconEvent_s {
RF_Revent_t type; /* what kind of event has occurred */
RF_RowCol_t col; /* row ID is implicit in the queue in which
* the event is placed */
void *arg; /* a generic argument */
RF_ReconEvent_t *next;
};
/*
* Reconstruction control information maintained per-disk
* (for surviving disks)
*/
struct RF_PerDiskReconCtrl_s {
RF_ReconCtrl_t *reconCtrl;
RF_RowCol_t row, col; /* to make this structure self-identifying */
RF_StripeNum_t curPSID; /* the next parity stripe ID to check on this
* disk */
RF_HeadSepLimit_t headSepCounter; /* counter used to control
* maximum head separation */
RF_SectorNum_t diskOffset; /* the offset into the indicated disk
* of the current PU */
RF_ReconUnitNum_t ru_count; /* this counts off the recon units
* within each parity unit */
RF_ReconBuffer_t *rbuf; /* the recon buffer assigned to this disk */
};
/* main reconstruction control structure */
struct RF_ReconCtrl_s {
RF_RaidReconDesc_t *reconDesc;
RF_RowCol_t fcol; /* which column has failed */
RF_PerDiskReconCtrl_t *perDiskInfo; /* information maintained
* per-disk */
RF_ReconMap_t *reconMap;/* map of what has/has not been reconstructed */
RF_RowCol_t spareRow; /* which of the spare disks we're using */
RF_RowCol_t spareCol;
RF_StripeNum_t lastPSID;/* the ID of the last parity stripe we want
* reconstructed */
int percentComplete;/* percentage completion of reconstruction */
/* reconstruction event queue */
RF_ReconEvent_t *eventQueue; /* queue of pending reconstruction
* events */
RF_DECLARE_MUTEX(eq_mutex) /* mutex for locking event
* queue */
RF_DECLARE_COND(eq_cond) /* condition variable for
* signalling recon events */
int eq_count; /* debug only */
/* reconstruction buffer management */
RF_DECLARE_MUTEX(rb_mutex) /* mutex for messing around
* with recon buffers */
RF_ReconBuffer_t *floatingRbufs; /* available floating
* reconstruction buffers */
RF_ReconBuffer_t *committedRbufs; /* recon buffers that have
* been committed to some
* waiting disk */
RF_ReconBuffer_t *fullBufferList; /* full buffers waiting to be
* written out */
RF_ReconBuffer_t *priorityList; /* full buffers that have been
* elevated to higher priority */
RF_CallbackDesc_t *bufferWaitList; /* disks that are currently
* blocked waiting for buffers */
/* parity stripe status table */
RF_PSStatusHeader_t *pssTable; /* stores the reconstruction status of
* active parity stripes */
/* maximum-head separation control */
RF_HeadSepLimit_t minHeadSepCounter; /* the minimum hs counter over
* all disks */
RF_CallbackDesc_t *headSepCBList; /* list of callbacks to be
* done as minPSID advances */
/* performance monitoring */
struct timeval starttime; /* recon start time */
void (*continueFunc) (void *); /* function to call when io
* returns */
void *continueArg; /* argument for Func */
};
/* the default priority for reconstruction accesses */
#define RF_IO_RECON_PRIORITY RF_IO_LOW_PRIORITY
int rf_ConfigureReconstruction(RF_ShutdownList_t ** listp);
int
rf_ReconstructFailedDisk(RF_Raid_t * raidPtr, RF_RowCol_t row,
RF_RowCol_t col);
int
rf_ReconstructFailedDiskBasic(RF_Raid_t * raidPtr, RF_RowCol_t row,
RF_RowCol_t col);
int
rf_ReconstructInPlace(RF_Raid_t * raidPtr, RF_RowCol_t row, RF_RowCol_t col);
int rf_ContinueReconstructFailedDisk(RF_RaidReconDesc_t * reconDesc);
int
rf_ForceOrBlockRecon(RF_Raid_t * raidPtr, RF_AccessStripeMap_t * asmap,
void (*cbFunc) (RF_Raid_t *, void *), void *cbArg);
int rf_UnblockRecon(RF_Raid_t * raidPtr, RF_AccessStripeMap_t * asmap);
int rf_RegisterReconDoneProc(RF_Raid_t * raidPtr, void (*proc) (RF_Raid_t *, void *), void *arg,
RF_ReconDoneProc_t ** handlep);
#endif /* !_RF__RF_RECONSTRUCT_H_ */
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