1 /*	$OpenBSD: rf_diskqueue.h,v 1.5 2002/12/16 07:01:03 tdeval Exp $	*/
2 /*	$NetBSD: rf_diskqueue.h,v 1.5 2000/02/13 04:53:57 oster Exp $	*/
3 
4 /*
5  * Copyright (c) 1995 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Author: Mark Holland
9  *
10  * Permission to use, copy, modify and distribute this software and
11  * its documentation is hereby granted, provided that both the copyright
12  * notice and this permission notice appear in all copies of the
13  * software, derivative works or modified versions, and any portions
14  * thereof, and that both notices appear in supporting documentation.
15  *
16  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19  *
20  * Carnegie Mellon requests users of this software to return to
21  *
22  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23  *  School of Computer Science
24  *  Carnegie Mellon University
25  *  Pittsburgh PA 15213-3890
26  *
27  * any improvements or extensions that they make and grant Carnegie the
28  * rights to redistribute these changes.
29  */
30 
31 /*****************************************************************************
32  *
33  * rf_diskqueue.h -- Header file for disk queues.
34  *
35  * See comments in rf_diskqueue.c
36  *
37  *****************************************************************************/
38 
39 
40 #ifndef	_RF__RF_DISKQUEUE_H_
41 #define	_RF__RF_DISKQUEUE_H_
42 
43 #include "rf_threadstuff.h"
44 #include "rf_acctrace.h"
45 #include "rf_alloclist.h"
46 #include "rf_types.h"
47 #include "rf_etimer.h"
48 
49 
50 #if	defined(__NetBSD__)
51 #include "rf_netbsd.h"
52 #elif	defined(__OpenBSD__)
53 #include "rf_openbsd.h"
54 #endif
55 
56 
57 #define	RF_IO_NORMAL_PRIORITY	1
58 #define	RF_IO_LOW_PRIORITY	0
59 
60 /* The data held by a disk queue entry. */
61 struct RF_DiskQueueData_s {
62 	RF_SectorNum_t	  sectorOffset;	/* Sector offset into the disk. */
63 	RF_SectorCount_t  numSector;	/* Number of sectors to read/write. */
64 	RF_IoType_t	  type;		/* Read/write/nop. */
65 	caddr_t		  buf;		/* Buffer pointer. */
66 	RF_StripeNum_t	  parityStripeID;
67 					/*
68 					 * The RAID parity stripe ID this
69 					 * access is for.
70 					 */
71 	RF_ReconUnitNum_t which_ru;	/* Which RU within this parity stripe */
72 	int		  priority;	/* The priority of this request. */
73 	int		(*CompleteFunc) (void *, int);
74 					/*
75 					 * Function to be called upon
76 					 * completion.
77 					 */
78 	int		(*AuxFunc) (void *,...);
79 					/*
80 					 * Function called upon completion
81 					 * of the first I/O of a Read_Op_Write
82 					 * pair.
83 					 */
84 	void		 *argument;	/*
85 					 * Argument to be passed to
86 					 * CompleteFunc.
87 					 */
88 	RF_Raid_t	 *raidPtr;	/* Needed for simulation. */
89 	RF_AccTraceEntry_t *tracerec;	/* Perf mon only. */
90 	RF_Etimer_t	  qtime;	/*
91 					 * Perf mon only - time request is
92 					 * in queue.
93 					 */
94 	long		  entryTime;
95 	RF_DiskQueueData_t *next;
96 	RF_DiskQueueData_t *prev;
97 	caddr_t		  buf2;		/* For read-op-write. */
98 	dev_t		  dev;		/*
99 					 * The device number for in-kernel
100 					 * version.
101 					 */
102 	RF_DiskQueue_t	 *queue;	/*
103 					 * The disk queue to which this req
104 					 * is targeted.
105 					 */
106 	RF_DiskQueueDataFlags_t flags;	/* Flags controlling operation. */
107 
108 	struct proc	 *b_proc;	/*
109 					 * The b_proc from the original bp
110 					 * passed into the driver for this I/O.
111 					 */
112 	struct buf	 *bp;		/* A bp to use to get this I/O done. */
113 };
114 #define	RF_LOCK_DISK_QUEUE	0x01
115 #define	RF_UNLOCK_DISK_QUEUE	0x02
116 
117 /*
118  * Note: "Create" returns type-specific queue header pointer cast to (void *).
119  */
120 struct RF_DiskQueueSW_s {
121 	RF_DiskQueueType_t queueType;
122 	void		*(*Create) (RF_SectorCount_t, RF_AllocListElem_t *,
123 			    RF_ShutdownList_t **);
124 					/*
125 					 * Creation routine -- one call per
126 					 * queue in system.
127 					 */
128 	void		 (*Enqueue) (void *, RF_DiskQueueData_t *, int);
129 					/* Enqueue routine. */
130 	RF_DiskQueueData_t *(*Dequeue) (void *);
131 					/* Dequeue routine. */
132 	RF_DiskQueueData_t *(*Peek) (void *);
133 					/* Peek at head of queue. */
134 
135 	/*
136 	 * The rest are optional:  they improve performance, but the driver
137 	 * will deal with it if they don't exist.
138 	 */
139 	int		 (*Promote) (void *, RF_StripeNum_t, RF_ReconUnitNum_t);
140 					/*
141 					 * Promotes priority of tagged
142 					 * accesses.
143 					 */
144 };
145 
146 struct RF_DiskQueue_s {
147 	RF_DiskQueueSW_t  *qPtr;	/* Access point to queue functions. */
148 	void		  *qHdr;	/* Queue header, of whatever type. */
149 	RF_DECLARE_MUTEX(mutex);	/* Mutex locking data structures. */
150 	RF_DECLARE_COND(cond);		/*
151 					 * Condition variable for
152 					 * synchronization.
153 					 */
154 	long		   numOutstanding;
155 					/*
156 					 * Number of I/Os currently
157 					 * outstanding on disk.
158 					 */
159 	long		   maxOutstanding;
160 					/*
161 					 * Max number of I/Os that can be
162 					 * outstanding on a disk.
163 					 * (in-kernel only)
164 					 */
165 	int		   curPriority;	/*
166 					 * The priority of accs all that are
167 					 * currently outstanding.
168 					 */
169 	long		   queueLength;	/* Number of requests in queue. */
170 	RF_DiskQueueData_t *nextLockingOp;
171 					/*
172 					 * A locking op that has arrived at
173 					 * the head of the queue & is waiting
174 					 * for drainage.
175 					 */
176 	RF_DiskQueueData_t *unlockingOp;/*
177 					 * Used at user level to communicate
178 					 * unlocking op b/w user (or dag exec)
179 					 * & disk threads.
180 					 */
181 	int		   numWaiting;	/*
182 					 * Number of threads waiting on
183 					 * this variable.
184 					 * (user-level only)
185 					 */
186 	RF_DiskQueueFlags_t flags;	/* Terminate, locked. */
187 	RF_Raid_t	  *raidPtr;	/* Associated array. */
188 	dev_t		   dev;		/* Device number for kernel version. */
189 	RF_SectorNum_t	   last_deq_sector;
190 					/*
191 					 * Last sector number dequeued or
192 					 * dispatched.
193 					 */
194 	int		   row, col;	/* Debug only. */
195 	struct raidcinfo  *rf_cinfo;	/* Disks component info... */
196 };
197 
198 /* No new accs allowed until queue is explicitly unlocked. */
199 #define	RF_DQ_LOCKED	0x02
200 
201 /* Macros setting & returning information about queues and requests. */
202 #define	RF_QUEUE_LOCKED(_q)		((_q)->flags & RF_DQ_LOCKED)
203 #define	RF_QUEUE_EMPTY(_q)		(((_q)->numOutstanding == 0) &&	\
204 					 ((_q)->nextLockingOp == NULL) && \
205 					 !RF_QUEUE_LOCKED(_q))
206 #define	RF_QUEUE_FULL(_q)		((_q)->numOutstanding ==	\
207 					 (_q)->maxOutstanding)
208 
209 #define	RF_LOCK_QUEUE(_q)		(_q)->flags |= RF_DQ_LOCKED
210 #define	RF_UNLOCK_QUEUE(_q)		(_q)->flags &= ~RF_DQ_LOCKED
211 
212 #define	RF_LOCK_QUEUE_MUTEX(_q_,_wh_)	RF_LOCK_MUTEX((_q_)->mutex)
213 #define	RF_UNLOCK_QUEUE_MUTEX(_q_,_wh_)	RF_UNLOCK_MUTEX((_q_)->mutex)
214 
215 #define	RF_LOCKING_REQ(_r)		((_r)->flags & RF_LOCK_DISK_QUEUE)
216 #define	RF_UNLOCKING_REQ(_r)		((_r)->flags & RF_UNLOCK_DISK_QUEUE)
217 
218 /* Whether it is ok to dispatch a regular request. */
219 #define	RF_OK_TO_DISPATCH(_q_,_r_)					\
220 	(RF_QUEUE_EMPTY(_q_) ||						\
221 	( !RF_QUEUE_FULL(_q_) && ((_r_)->priority >= (_q_)->curPriority)))
222 
223 int  rf_ConfigureDiskQueueSystem(RF_ShutdownList_t **);
224 
225 void rf_TerminateDiskQueues(RF_Raid_t *);
226 
227 int  rf_ConfigureDiskQueues(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
228 
229 void rf_DiskIOEnqueue(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
230 
231 void rf_DiskIOComplete(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
232 
233 int  rf_DiskIOPromote(RF_DiskQueue_t *, RF_StripeNum_t, RF_ReconUnitNum_t);
234 
235 RF_DiskQueueData_t *rf_CreateDiskQueueData(RF_IoType_t, RF_SectorNum_t,
236 	RF_SectorCount_t, caddr_t, RF_StripeNum_t, RF_ReconUnitNum_t,
237 	int (*) (void *, int), void *, RF_DiskQueueData_t *,
238 	RF_AccTraceEntry_t *, void *, RF_DiskQueueDataFlags_t, void *);
239 
240 RF_DiskQueueData_t *rf_CreateDiskQueueDataFull(RF_IoType_t, RF_SectorNum_t,
241 	RF_SectorCount_t, caddr_t, RF_StripeNum_t, RF_ReconUnitNum_t,
242 	int (*) (void *, int), void *, RF_DiskQueueData_t *,
243 	RF_AccTraceEntry_t *, int, int (*) (void *,...), caddr_t, void *,
244 	RF_DiskQueueDataFlags_t, void *);
245 
246 void rf_FreeDiskQueueData(RF_DiskQueueData_t *);
247 
248 int  rf_ConfigureDiskQueue(RF_Raid_t *, RF_DiskQueue_t *, RF_RowCol_t,
249 	RF_RowCol_t, RF_DiskQueueSW_t *, RF_SectorCount_t, dev_t, int,
250 	RF_ShutdownList_t **, RF_AllocListElem_t *);
251 
252 #endif	/* ! _RF__RF_DISKQUEUE_H_ */
253