text: /*	$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_ */
  