1 /*	$OpenBSD: rf_sstf.h,v 1.3 2002/12/16 07:01:05 tdeval Exp $	*/
2 /*	$NetBSD: rf_sstf.h,v 1.3 1999/02/05 00:06:17 oster Exp $	*/
3 
4 /*
5  * Copyright (c) 1995 Carnegie-Mellon University.
6  * All rights reserved.
7  *
8  * Author: Jim Zelenka
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 #ifndef	_RF__RF_SSTF_H_
32 #define	_RF__RF_SSTF_H_
33 
34 #include "rf_diskqueue.h"
35 
36 typedef struct RF_SstfQ_s {
37 	RF_DiskQueueData_t	*queue;
38 	RF_DiskQueueData_t	*qtail;
39 	int			 qlen;
40 } RF_SstfQ_t;
41 
42 typedef struct RF_Sstf_s {
43 	RF_SstfQ_t		 left;
44 	RF_SstfQ_t		 right;
45 	RF_SstfQ_t		 lopri;
46 	RF_SectorNum_t		 last_sector;
47 	int			 dir;
48 	int			 allow_reverse;
49 } RF_Sstf_t;
50 
51 void *rf_SstfCreate(RF_SectorCount_t, RF_AllocListElem_t *,
52 	RF_ShutdownList_t **);
53 void *rf_ScanCreate(RF_SectorCount_t, RF_AllocListElem_t *,
54 	RF_ShutdownList_t **);
55 void *rf_CscanCreate(RF_SectorCount_t, RF_AllocListElem_t *,
56 	RF_ShutdownList_t **);
57 void  rf_SstfEnqueue(void *, RF_DiskQueueData_t *, int);
58 RF_DiskQueueData_t *rf_SstfDequeue(void *);
59 RF_DiskQueueData_t *rf_SstfPeek(void *);
60 int   rf_SstfPromote(void *, RF_StripeNum_t, RF_ReconUnitNum_t);
61 RF_DiskQueueData_t *rf_ScanDequeue(void *);
62 RF_DiskQueueData_t *rf_ScanPeek(void *);
63 RF_DiskQueueData_t *rf_CscanDequeue(void *);
64 RF_DiskQueueData_t *rf_CscanPeek(void *);
65 
66 #endif	/* !_RF__RF_SSTF_H_ */
67