1/* $NetBSD: rf_diskqueue.h,v 1.24 2011/05/05 06:04:09 mrg 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 <sys/queue.h>
42
43#include <dev/raidframe/raidframevar.h>
44
45#include "rf_threadstuff.h"
46#include "rf_acctrace.h"
47#include "rf_alloclist.h"
48#include "rf_etimer.h"
49#include "rf_netbsd.h"
50
51
52#define RF_IO_NORMAL_PRIORITY 1
53#define RF_IO_LOW_PRIORITY 0
54
55/* the data held by a disk queue entry */
56struct RF_DiskQueueData_s {
57 RF_SectorNum_t sectorOffset; /* sector offset into the disk */
58 RF_SectorCount_t numSector; /* number of sectors to read/write */
59 RF_IoType_t type; /* read/write/nop */
60 void *buf; /* buffer pointer */
61 RF_StripeNum_t parityStripeID; /* the RAID parity stripe ID this
62 * access is for */
63 RF_ReconUnitNum_t which_ru; /* which RU within this parity stripe */
64 int priority; /* the priority of this request */
65 int (*CompleteFunc) (void *, int); /* function to be called upon
66 * completion */
67 void *argument; /* argument to be passed to CompleteFunc */
68 RF_Raid_t *raidPtr; /* needed for simulation */
69 RF_AccTraceEntry_t *tracerec; /* perf mon only */
70 RF_Etimer_t qtime; /* perf mon only - time request is in queue */
71 RF_DiskQueueData_t *next;
72 RF_DiskQueueData_t *prev;
73 RF_DiskQueue_t *queue; /* the disk queue to which this req is
74 * targeted */
75 RF_DiskQueueDataFlags_t flags; /* flags controlling operation */
76
77 struct proc *b_proc; /* the b_proc from the original bp passed into
78 * the driver for this I/O */
79 struct buf *bp; /* a bp to use to get this I/O done */
80 /* TAILQ bits for a queue for completed I/O requests */
81 TAILQ_ENTRY(RF_DiskQueueData_s) iodone_entries;
82 int error; /* Indicate if an error occurred
83 on this I/O (1=yes, 0=no) */
84};
85
86/* note: "Create" returns type-specific queue header pointer cast to (void *) */
87struct RF_DiskQueueSW_s {
88 RF_DiskQueueType_t queueType;
89 void *(*Create) (RF_SectorCount_t, RF_AllocListElem_t *, RF_ShutdownList_t **); /* creation routine --
90 * one call per queue in
91 * system */
92 void (*Enqueue) (void *, RF_DiskQueueData_t *, int); /* enqueue routine */
93 RF_DiskQueueData_t *(*Dequeue) (void *); /* dequeue routine */
94 RF_DiskQueueData_t *(*Peek) (void *); /* peek at head of queue */
95
96 /* the rest are optional: they improve performance, but the driver
97 * will deal with it if they don't exist */
98 int (*Promote) (void *, RF_StripeNum_t, RF_ReconUnitNum_t); /* promotes priority of
99 * tagged accesses */
100};
101
102struct RF_DiskQueue_s {
103 const RF_DiskQueueSW_t *qPtr; /* access point to queue functions */
104 void *qHdr; /* queue header, of whatever type */
105 rf_declare_mutex2(mutex);/* mutex locking data structures */
106 long numOutstanding; /* number of I/Os currently outstanding on
107 * disk */
108 long maxOutstanding; /* max # of I/Os that can be outstanding on a
109 * disk (in-kernel only) */
110 int curPriority; /* the priority of accs all that are currently
111 * outstanding */
112 long queueLength; /* number of requests in queue */
113 RF_DiskQueueFlags_t flags; /* terminate, locked */
114 RF_Raid_t *raidPtr; /* associated array */
115 dev_t dev; /* device number for kernel version */
116 RF_SectorNum_t last_deq_sector; /* last sector number dequeued or
117 * dispatched */
118 int col; /* debug only */
119 struct raidcinfo *rf_cinfo; /* disks component info.. */
120};
121#define RF_DQ_LOCKED 0x02 /* no new accs allowed until queue is
122 * explicitly unlocked */
123
124/* macros setting & returning information about queues and requests */
125#define RF_QUEUE_EMPTY(_q) ((_q)->numOutstanding == 0)
126#define RF_QUEUE_FULL(_q) ((_q)->numOutstanding == (_q)->maxOutstanding)
127
128#define RF_LOCK_QUEUE_MUTEX(_q_,_wh_) rf_lock_mutex2((_q_)->mutex)
129#define RF_UNLOCK_QUEUE_MUTEX(_q_,_wh_) rf_unlock_mutex2((_q_)->mutex)
130
131/* whether it is ok to dispatch a regular request */
132#define RF_OK_TO_DISPATCH(_q_,_r_) \
133 (RF_QUEUE_EMPTY(_q_) || \
134 (!RF_QUEUE_FULL(_q_) && ((_r_)->priority >= (_q_)->curPriority)))
135
136int rf_ConfigureDiskQueueSystem(RF_ShutdownList_t **);
137int rf_ConfigureDiskQueues(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
138void rf_DiskIOEnqueue(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
139void rf_DiskIOComplete(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
140int rf_DiskIOPromote(RF_DiskQueue_t *, RF_StripeNum_t, RF_ReconUnitNum_t);
141RF_DiskQueueData_t *rf_CreateDiskQueueData(RF_IoType_t, RF_SectorNum_t,
142 RF_SectorCount_t , void *,
143 RF_StripeNum_t, RF_ReconUnitNum_t,
144 int (*wakeF) (void *, int),
145 void *,
146 RF_AccTraceEntry_t *, RF_Raid_t *,
147 RF_DiskQueueDataFlags_t,
148 void *, int);
149void rf_FreeDiskQueueData(RF_DiskQueueData_t *);
150int rf_ConfigureDiskQueue(RF_Raid_t *, RF_DiskQueue_t *,
151 RF_RowCol_t, const RF_DiskQueueSW_t *,
152 RF_SectorCount_t, dev_t, int,
153 RF_ShutdownList_t **,
154 RF_AllocListElem_t *);
155
156#endif /* !_RF__RF_DISKQUEUE_H_ */
157