/*      $NetBSD: rf_paritylog.h,v 1.13 2019/10/10 03:43:59 christos Exp $       */
/*
 * Copyright (c) 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: William V. Courtright II
 *
 * 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.
 */

/* header file for parity log
 *
 */

#ifndef _RF__RF_PARITYLOG_H_
#define _RF__RF_PARITYLOG_H_

#include <dev/raidframe/raidframevar.h>

#define RF_DEFAULT_NUM_SECTORS_PER_LOG 64

typedef int RF_RegionId_t;

typedef enum RF_ParityRecordType_e {
        RF_STOP,
        RF_UPDATE,
        RF_OVERWRITE
}       RF_ParityRecordType_t;

struct RF_CommonLogData_s {
        rf_declare_mutex2(mutex);       /* protects cnt */
        int     cnt;                    /* when 0, time to call wakeFunc */
        RF_Raid_t *raidPtr;
        void  (*wakeFunc) (void *, int);
        void   *wakeArg;
        RF_AccTraceEntry_t *tracerec;
        RF_Etimer_t startTime;
        void *bufPtr;
        RF_ParityRecordType_t operation;
        RF_CommonLogData_t *next;
};

struct RF_ParityLogData_s {
        RF_RegionId_t regionID; /* this struct guaranteed to span a single
                                 * region */
        int     bufOffset;      /* offset from common->bufPtr */
        RF_PhysDiskAddr_t diskAddress;
        RF_CommonLogData_t *common;     /* info shared by one or more
                                         * parityLogData structs */
        RF_ParityLogData_t *next;
        RF_ParityLogData_t *prev;
};

struct RF_ParityLogAppendQueue_s {
        rf_declare_mutex2(mutex);
};

struct RF_ParityLogRecord_s {
        RF_PhysDiskAddr_t parityAddr;
        RF_ParityRecordType_t operation;
};

struct RF_ParityLog_s {
        RF_RegionId_t regionID;
        int     numRecords;
        int     diskOffset;
        RF_ParityLogRecord_t *records;
        void *bufPtr;
        RF_ParityLog_t *next;
};

struct RF_ParityLogQueue_s {
        rf_declare_mutex2(mutex);
        RF_ParityLog_t *parityLogs;
};

struct RF_RegionBufferQueue_s {
        rf_declare_mutex2(mutex);
        rf_declare_cond2(cond);
        int     bufferSize;
        int     totalBuffers;   /* size of array 'buffers' */
        int     availableBuffers;       /* num available 'buffers' */
        int     emptyBuffersIndex;      /* stick next freed buffer here */
        int     availBuffersIndex;      /* grab next buffer from here */
        void **buffers; /* array buffers used to hold parity */
};
#define RF_PLOG_CREATED   (1<<0)/* thread is created */
#define RF_PLOG_RUNNING   (1<<1)/* thread is running */
#define RF_PLOG_TERMINATE (1<<2)/* thread is terminated (should exit) */
#define RF_PLOG_SHUTDOWN  (1<<3)/* thread is aware and exiting/exited */

struct RF_ParityLogDiskQueue_s {
        rf_declare_mutex2(mutex);/* protects all vars in this struct */
        rf_declare_cond2(cond);
        int     threadState;    /* is thread running, should it shutdown  (see
                                 * above) */
        RF_ParityLog_t *flushQueue;     /* list of parity logs to be flushed
                                         * to log disk */
        RF_ParityLog_t *reintQueue;     /* list of parity logs waiting to be
                                         * reintegrated */
        RF_ParityLogData_t *bufHead;    /* head of FIFO list of log data,
                                         * waiting on a buffer */
        RF_ParityLogData_t *bufTail;    /* tail of FIFO list of log data,
                                         * waiting on a buffer */
        RF_ParityLogData_t *reintHead;  /* head of FIFO list of log data,
                                         * waiting on reintegration */
        RF_ParityLogData_t *reintTail;  /* tail of FIFO list of log data,
                                         * waiting on reintegration */
        RF_ParityLogData_t *logBlockHead;       /* queue of work, blocked
                                                 * until a log is available */
        RF_ParityLogData_t *logBlockTail;
        RF_ParityLogData_t *reintBlockHead;     /* queue of work, blocked
                                                 * until reintegration is
                                                 * complete */
        RF_ParityLogData_t *reintBlockTail;
        RF_CommonLogData_t *freeCommonList;     /* list of unused common data
                                                 * structs */
        RF_ParityLogData_t *freeDataList;       /* list of unused log data
                                                 * structs */
};

struct RF_DiskMap_s {
        RF_PhysDiskAddr_t parityAddr;
        RF_ParityRecordType_t operation;
};

struct RF_RegionInfo_s {
        rf_declare_mutex2(mutex);       /* protects: diskCount, diskMap,
                                         * loggingEnabled, coreLog */
        rf_declare_mutex2(reintMutex);  /* protects: reintInProgress */
        int     reintInProgress;/* flag used to suspend flushing operations */
        RF_SectorCount_t capacity;      /* capacity of this region in sectors */
        RF_SectorNum_t regionStartAddr; /* starting disk address for this
                                         * region */
        RF_SectorNum_t parityStartAddr; /* starting disk address for this
                                         * region */
        RF_SectorCount_t numSectorsParity;      /* number of parity sectors
                                                 * protected by this region */
        RF_SectorCount_t diskCount;     /* num of sectors written to this
                                         * region's disk log */
        RF_DiskMap_t *diskMap;  /* in-core map of what's in this region's disk
                                 * log */
        int     loggingEnabled; /* logging enable for this region */
        RF_ParityLog_t *coreLog;/* in-core log for this region */
};

RF_ParityLogData_t *
rf_CreateParityLogData(RF_ParityRecordType_t operation,
    RF_PhysDiskAddr_t * pda, void *bufPtr, RF_Raid_t * raidPtr,
    void (*wakeFunc) (void *, int),
    void *wakeArg, RF_AccTraceEntry_t * tracerec,
    RF_Etimer_t startTime);
        RF_ParityLogData_t *rf_SearchAndDequeueParityLogData(RF_Raid_t * raidPtr,
            RF_RegionId_t regionID, RF_ParityLogData_t ** head,
            RF_ParityLogData_t ** tail, int ignoreLocks);
        void    rf_ReleaseParityLogs(RF_Raid_t * raidPtr, RF_ParityLog_t * firstLog);
        int     rf_ParityLogAppend(RF_ParityLogData_t * logData, int finish,
            RF_ParityLog_t ** incomingLog, int clearReintFlag);
        void    rf_EnableParityLogging(RF_Raid_t * raidPtr);

#endif                          /* !_RF__RF_PARITYLOG_H_ */