/* $NetBSD: rf_diskqueue.h,v 1.30 2023/09/17 20:07:39 oster Exp $ */

/* $NetBSD: rf_diskqueue.h,v 1.30 2023/09/17 20:07:39 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 [email protected]
* 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_diskqueue.h -- header file for disk queues
*
* see comments in rf_diskqueue.c
*
****************************************************************************************/

#ifndef _RF__RF_DISKQUEUE_H_
#define _RF__RF_DISKQUEUE_H_

#include <sys/queue.h>

#include <dev/raidframe/raidframevar.h>

#include "rf_threadstuff.h"
#include "rf_acctrace.h"
#include "rf_alloclist.h"
#include "rf_etimer.h"
#include "rf_netbsd.h"

#define RF_IO_NORMAL_PRIORITY 1
#define RF_IO_LOW_PRIORITY 0

/* the data held by a disk queue entry */
struct RF_DiskQueueData_s {
RF_SectorNum_t sectorOffset; /* sector offset into the disk */
RF_SectorCount_t numSector; /* number of sectors to read/write */
RF_IoType_t type; /* read/write/nop */
void *buf; /* buffer pointer */
RF_StripeNum_t parityStripeID; /* the RAID parity stripe ID this
* access is for */
RF_ReconUnitNum_t which_ru; /* which RU within this parity stripe */
int priority; /* the priority of this request */
void (*CompleteFunc) (void *, int); /* function to be called upon
* completion */
void *argument; /* argument to be passed to CompleteFunc */
RF_Raid_t *raidPtr; /* needed for simulation */
RF_AccTraceEntry_t *tracerec; /* perf mon only */
RF_Etimer_t qtime; /* perf mon only - time request is in queue */
RF_DiskQueueData_t *next;
RF_DiskQueueData_t *prev;
RF_DiskQueue_t *queue; /* the disk queue to which this req is
* targeted */
RF_DiskQueueDataFlags_t flags; /* flags controlling operation */

struct buf *bp; /* a bp to use to get this I/O done */
/* TAILQ bits for a queue for completed I/O requests */
TAILQ_ENTRY(RF_DiskQueueData_s) iodone_entries;
int error; /* Indicate if an error occurred
on this I/O (1=yes, 0=no) */
};

/* note: "Create" returns type-specific queue header pointer cast to (void *) */
struct RF_DiskQueueSW_s {
RF_DiskQueueType_t queueType;
void *(*Create) (RF_SectorCount_t, RF_AllocListElem_t *, RF_ShutdownList_t **); /* creation routine --
* one call per queue in
* system */
void (*Enqueue) (void *, RF_DiskQueueData_t *, int); /* enqueue routine */
RF_DiskQueueData_t *(*Dequeue) (void *); /* dequeue routine */

/* the rest are optional: they improve performance, but the driver
* will deal with it if they don't exist */
int (*Promote) (void *, RF_StripeNum_t, RF_ReconUnitNum_t); /* promotes priority of
* tagged accesses */
};

struct RF_DiskQueue_s {
const RF_DiskQueueSW_t *qPtr; /* access point to queue functions */
void *qHdr; /* queue header, of whatever type */
rf_declare_mutex2(mutex);/* mutex locking data structures */
long numOutstanding; /* number of I/Os currently outstanding on
* disk */
long maxOutstanding; /* max # of I/Os that can be outstanding on a
* disk (in-kernel only) */
int curPriority; /* the priority of accs all that are currently
* outstanding */
long queueLength; /* number of requests in queue */
RF_DiskQueueFlags_t flags; /* terminate, locked */
RF_Raid_t *raidPtr; /* associated array */
dev_t dev; /* device number for kernel version */
RF_SectorNum_t last_deq_sector; /* last sector number dequeued or
* dispatched */
int col; /* debug only */
struct raidcinfo *rf_cinfo; /* disks component info.. */
};
#define RF_DQ_LOCKED 0x02 /* no new accs allowed until queue is
* explicitly unlocked */

/* macros setting & returning information about queues and requests */
#define RF_QUEUE_EMPTY(_q) ((_q)->numOutstanding == 0)
#define RF_QUEUE_FULL(_q) ((_q)->numOutstanding == (_q)->maxOutstanding)

#define RF_LOCK_QUEUE_MUTEX(_q_,_wh_) rf_lock_mutex2((_q_)->mutex)
#define RF_UNLOCK_QUEUE_MUTEX(_q_,_wh_) rf_unlock_mutex2((_q_)->mutex)

/* whether it is ok to dispatch a regular request */
#define RF_OK_TO_DISPATCH(_q_,_r_) \
(RF_QUEUE_EMPTY(_q_) || \
(!RF_QUEUE_FULL(_q_) && ((_r_)->priority >= (_q_)->curPriority)))

int rf_ConfigureDiskQueueSystem(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
int rf_ConfigureDiskQueues(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
void rf_DiskIOEnqueue(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
void rf_DiskIOComplete(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
int rf_DiskIOPromote(RF_DiskQueue_t *, RF_StripeNum_t, RF_ReconUnitNum_t);
RF_DiskQueueData_t *rf_CreateDiskQueueData(RF_IoType_t, RF_SectorNum_t,
RF_SectorCount_t , void *,
RF_StripeNum_t, RF_ReconUnitNum_t,
void (*wakeF) (void *, int),
void *,
RF_AccTraceEntry_t *, RF_Raid_t *,
RF_DiskQueueDataFlags_t,
const struct buf *);
void rf_FreeDiskQueueData(RF_DiskQueueData_t *);
int rf_ConfigureDiskQueue(RF_Raid_t *, RF_DiskQueue_t *,
RF_RowCol_t, const RF_DiskQueueSW_t *,
RF_SectorCount_t, dev_t, int,
RF_ShutdownList_t **,
RF_AllocListElem_t *);
int rf_UpdateDiskQueue(RF_DiskQueue_t *, RF_RaidDisk_t *);

#endif /* !_RF__RF_DISKQUEUE_H_ */