1/*	$NetBSD: rf_sstf.h,v 1.6 2021/07/23 20:18:24 oster Exp $	*/
2/*
3 * Copyright (c) 1995 Carnegie-Mellon University.
4 * All rights reserved.
5 *
6 * Author: Jim Zelenka
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#ifndef _RF__RF_SSTF_H_
30#define _RF__RF_SSTF_H_
31
32#include "rf_diskqueue.h"
33
34typedef struct RF_SstfQ_s {
35	RF_DiskQueueData_t *queue;
36	RF_DiskQueueData_t *qtail;
37	int     qlen;
38}       RF_SstfQ_t;
39
40typedef struct RF_Sstf_s {
41	RF_SstfQ_t left;
42	RF_SstfQ_t right;
43	RF_SstfQ_t lopri;
44	RF_SectorNum_t last_sector;
45	int     dir;
46	int     allow_reverse;
47}       RF_Sstf_t;
48
49void   *
50rf_SstfCreate(RF_SectorCount_t sect_per_disk,
51    RF_AllocListElem_t * cl_list, RF_ShutdownList_t ** listp);
52void   *
53rf_ScanCreate(RF_SectorCount_t sect_per_disk,
54    RF_AllocListElem_t * cl_list, RF_ShutdownList_t ** listp);
55void   *
56rf_CscanCreate(RF_SectorCount_t sect_per_disk,
57    RF_AllocListElem_t * cl_list, RF_ShutdownList_t ** listp);
58void    rf_SstfEnqueue(void *qptr, RF_DiskQueueData_t * req, int priority);
59RF_DiskQueueData_t *rf_SstfDequeue(void *qptr);
60int
61rf_SstfPromote(void *qptr, RF_StripeNum_t parityStripeID,
62    RF_ReconUnitNum_t which_ru);
63RF_DiskQueueData_t *rf_ScanDequeue(void *qptr);
64RF_DiskQueueData_t *rf_CscanDequeue(void *qptr);
65
66#endif				/* !_RF__RF_SSTF_H_ */
67