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_ */