rf_diskqueue.h revision 1.2 
1/*	$NetBSD: rf_diskqueue.h,v 1.2 1999/01/26 02:33:56 oster Exp $	*/
2/*
3 * Copyright (c) 1995 Carnegie-Mellon University.
4 * All rights reserved.
5 *
6 * Author: Mark Holland
7 *
8 * Permission to use, copy, modify and distribute this software and
9 * its documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
16 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21 *  School of Computer Science
22 *  Carnegie Mellon University
23 *  Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
27 */
28
29/*****************************************************************************************
30 *
31 * rf_diskqueue.h -- header file for disk queues
32 *
33 * see comments in rf_diskqueue.c
34 *
35 ****************************************************************************************/
36
37
38#ifndef _RF__RF_DISKQUEUE_H_
39#define _RF__RF_DISKQUEUE_H_
40
41#include "rf_threadstuff.h"
42#include "rf_acctrace.h"
43#include "rf_alloclist.h"
44#include "rf_types.h"
45#include "rf_etimer.h"
46
47
48#include "rf_netbsd.h"
49
50
51#define RF_IO_NORMAL_PRIORITY 1
52#define RF_IO_LOW_PRIORITY    0
53
54/* the data held by a disk queue entry */
55struct RF_DiskQueueData_s {
56  RF_SectorNum_t           sectorOffset;   /* sector offset into the disk */
57  RF_SectorCount_t         numSector;      /* number of sectors to read/write */
58  RF_IoType_t              type;           /* read/write/nop */
59  caddr_t                  buf;            /* buffer pointer */
60  RF_StripeNum_t           parityStripeID; /* the RAID parity stripe ID this access is for */
61  RF_ReconUnitNum_t        which_ru;       /* which RU within this parity stripe */
62  int                      priority;       /* the priority of this request */
63  int                    (*CompleteFunc)(void *,int);/* function to be called upon completion */
64  int                    (*AuxFunc)(void *,...); /* function called upon completion of the first I/O of a Read_Op_Write pair*/
65  void                    *argument;       /* argument to be passed to CompleteFunc */
66  void                    *raidPtr;        /* needed for simulation */
67  RF_AccTraceEntry_t      *tracerec;       /* perf mon only */
68  RF_Etimer_t              qtime;          /* perf mon only - time request is in queue */
69  long                     entryTime;
70  RF_DiskQueueData_t      *next;
71  RF_DiskQueueData_t      *prev;
72  caddr_t                  buf2;   /* for read-op-write */
73  dev_t                    dev;    /* the device number for in-kernel version */
74  RF_DiskQueue_t          *queue;  /* the disk queue to which this req is targeted */
75  RF_DiskQueueDataFlags_t  flags;  /* flags controlling operation */
76
77  struct proc             *b_proc;  /* the b_proc from the original bp passed into the driver for this I/O */
78  struct buf              *bp;      /* a bp to use to get this I/O done */
79};
80
81#define RF_LOCK_DISK_QUEUE   0x01
82#define RF_UNLOCK_DISK_QUEUE 0x02
83
84/* note: "Create" returns type-specific queue header pointer cast to (void *) */
85struct RF_DiskQueueSW_s {
86  RF_DiskQueueType_t     queueType;
87  void                *(*Create)(RF_SectorCount_t, RF_AllocListElem_t *, RF_ShutdownList_t **);    /* creation routine -- one call per queue in system */
88  void                 (*Enqueue)(void *,RF_DiskQueueData_t * ,int);   /* enqueue routine */
89  RF_DiskQueueData_t  *(*Dequeue)(void *);   /* dequeue routine */
90  RF_DiskQueueData_t  *(*Peek)(void *);      /* peek at head of queue */
91
92  /* the rest are optional:  they improve performance, but the driver will deal with it if they don't exist */
93  int                  (*Promote)(void *, RF_StripeNum_t, RF_ReconUnitNum_t);   /* promotes priority of tagged accesses */
94};
95
96struct RF_DiskQueue_s {
97  RF_DiskQueueSW_t    *qPtr;             /* access point to queue functions */
98  void                *qHdr;             /* queue header, of whatever type */
99  RF_DECLARE_MUTEX(mutex)                /* mutex locking data structures */
100  RF_DECLARE_COND(cond)                  /* condition variable for synchronization */
101  long                 numOutstanding;   /* number of I/Os currently outstanding on disk */
102  long                 maxOutstanding;   /* max # of I/Os that can be outstanding on a disk (in-kernel only) */
103  int                  curPriority;      /* the priority of accs all that are currently outstanding */
104  long                 queueLength;      /* number of requests in queue */
105  RF_DiskQueueData_t  *nextLockingOp;    /* a locking op that has arrived at the head of the queue & is waiting for drainage */
106  RF_DiskQueueData_t  *unlockingOp;      /* used at user level to communicate unlocking op b/w user (or dag exec) & disk threads */
107  int                  numWaiting;       /* number of threads waiting on this variable.  user-level only */
108  RF_DiskQueueFlags_t  flags;            /* terminate, locked */
109  RF_Raid_t           *raidPtr;          /* associated array */
110  dev_t                dev;              /* device number for kernel version */
111  RF_SectorNum_t       last_deq_sector;  /* last sector number dequeued or dispatched */
112  int                  row, col;         /* debug only */
113  struct raidcinfo *rf_cinfo;      /* disks component info.. */
114};
115
116#define RF_DQ_LOCKED  0x02  /* no new accs allowed until queue is explicitly unlocked */
117
118/* macros setting & returning information about queues and requests */
119#define RF_QUEUE_LOCKED(_q)                 ((_q)->flags & RF_DQ_LOCKED)
120#define RF_QUEUE_EMPTY(_q)                  (((_q)->numOutstanding == 0) && ((_q)->nextLockingOp == NULL) && !RF_QUEUE_LOCKED(_q))
121#define RF_QUEUE_FULL(_q)                   ((_q)->numOutstanding == (_q)->maxOutstanding)
122
123#define RF_LOCK_QUEUE(_q)                   (_q)->flags |= RF_DQ_LOCKED
124#define RF_UNLOCK_QUEUE(_q)                 (_q)->flags &= ~RF_DQ_LOCKED
125
126#define RF_LOCK_QUEUE_MUTEX(_q_,_wh_)   RF_LOCK_MUTEX((_q_)->mutex)
127#define RF_UNLOCK_QUEUE_MUTEX(_q_,_wh_) RF_UNLOCK_MUTEX((_q_)->mutex)
128
129#define RF_LOCKING_REQ(_r)                  ((_r)->flags & RF_LOCK_DISK_QUEUE)
130#define RF_UNLOCKING_REQ(_r)                ((_r)->flags & RF_UNLOCK_DISK_QUEUE)
131
132/* whether it is ok to dispatch a regular request */
133#define RF_OK_TO_DISPATCH(_q_,_r_) \
134  (RF_QUEUE_EMPTY(_q_) || \
135    (!RF_QUEUE_FULL(_q_) && ((_r_)->priority >= (_q_)->curPriority)))
136
137int rf_ConfigureDiskQueueSystem(RF_ShutdownList_t **listp);
138
139void rf_TerminateDiskQueues(RF_Raid_t *raidPtr);
140
141int rf_ConfigureDiskQueues(RF_ShutdownList_t **listp, RF_Raid_t *raidPtr,
142	RF_Config_t *cfgPtr);
143
144void rf_DiskIOEnqueue(RF_DiskQueue_t *queue, RF_DiskQueueData_t *req, int pri);
145
146
147void rf_DiskIOComplete(RF_DiskQueue_t *queue, RF_DiskQueueData_t *req, int status);
148
149int rf_DiskIOPromote(RF_DiskQueue_t *queue, RF_StripeNum_t parityStripeID,
150	RF_ReconUnitNum_t which_ru);
151
152RF_DiskQueueData_t *rf_CreateDiskQueueData(RF_IoType_t typ,
153	RF_SectorNum_t ssect, RF_SectorCount_t nsect, caddr_t buf,
154	RF_StripeNum_t parityStripeID, RF_ReconUnitNum_t which_ru,
155        int (*wakeF)(void *, int),
156	void *arg, RF_DiskQueueData_t *next, RF_AccTraceEntry_t *tracerec,
157	void *raidPtr, RF_DiskQueueDataFlags_t flags, void *kb_proc);
158
159RF_DiskQueueData_t *rf_CreateDiskQueueDataFull(RF_IoType_t typ,
160	RF_SectorNum_t ssect, RF_SectorCount_t nsect, caddr_t buf,
161	RF_StripeNum_t parityStripeID, RF_ReconUnitNum_t which_ru,
162        int (*wakeF)(void *, int),
163	void *arg, RF_DiskQueueData_t *next, RF_AccTraceEntry_t *tracerec,
164	int priority, int (*AuxFunc)(void *,...), caddr_t buf2,
165	void *raidPtr, RF_DiskQueueDataFlags_t flags, void *kb_proc);
166
167void rf_FreeDiskQueueData(RF_DiskQueueData_t *p);
168
169#endif /* !_RF__RF_DISKQUEUE_H_ */
170