1 /*	$OpenBSD: rf_decluster.h,v 1.3 2002/12/16 07:01:03 tdeval Exp $	*/
2 /*	$NetBSD: rf_decluster.h,v 1.3 1999/02/05 00:06:09 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  * decluster.h -- Header file for declustered layout code.
34  *
35  * Adapted from raidSim version July 1994
36  * Created 10-21-92 (MCH)
37  *
38  *****************************************************************************/
39 
40 #ifndef	_RF__RF_DECLUSTER_H_
41 #define	_RF__RF_DECLUSTER_H_
42 
43 #include "rf_types.h"
44 
45 /*
46  * These structures define the tables used to locate the spare unit
47  * associated with a particular data or parity unit, and to perform
48  * the associated inverse mapping.
49  */
50 struct RF_SpareTableEntry_s {
51 	u_int	spareDisk;		/* Disk where this block is spared. */
52 	u_int	spareBlockOffsetInSUs;	/*
53 					 * Offset into spare table for that
54 					 * disk.
55 					 */
56 };
57 
58 #define	RF_SPAREMAP_NAME_LEN	128
59 
60 /*
61  * This is the layout-specific info structure for the declustered layout.
62  */
63 struct RF_DeclusteredConfigInfo_s {
64 		/* Number of stripe units per parity stripe. */
65 	RF_StripeCount_t	  groupSize;
66 		/* The block design table. */
67 	RF_RowCol_t		**LayoutTable;
68 	RF_RowCol_t		**OffsetTable;
69 		/* The sector offset table. */
70 	RF_RowCol_t		**BlockTable;
71 		/* The block membership table. */
72 	RF_StripeCount_t	  SUsPerFullTable;
73 		/* Stripe units per full table. */
74 	RF_StripeCount_t	  SUsPerTable;
75 		/* Stripe units per table. */
76 	RF_StripeCount_t	  PUsPerBlock;
77 		/* Parity units per block. */
78 	RF_StripeCount_t	  SUsPerBlock;
79 		/* Stripe units per block. */
80 	RF_StripeCount_t	  BlocksPerTable;
81 		/* Block design tuples per table. */
82 	RF_StripeCount_t	  NumParityReps;
83 		/* Tables per full table. */
84 	RF_StripeCount_t	  TableDepthInPUs;
85 		/* PUs on one disk in 1 table. */
86 	RF_StripeCount_t	  FullTableDepthInPUs;
87 		/* PUs on one disk in 1 fulltable. */
88 	RF_StripeCount_t	  FullTableLimitSUID;
89 		/* SU where partial fulltables start. */
90 	RF_StripeCount_t	  ExtraTablesPerDisk;
91 		/* Number of tables in last fulltable. */
92 	RF_SectorNum_t		  DiskOffsetOfLastFullTableInSUs;
93 		/* Disk offsets of partial fulltable, if any. */
94 	RF_StripeCount_t	  numCompleteFullTablesPerDisk;
95 		/* Fulltable identifier of partial fulltable, if any. */
96 	u_int			  Lambda;
97 		/* The pair count in the block design. */
98 
99 	/* These are used only in the distributed-sparing case. */
100 	RF_StripeCount_t	  FullTablesPerSpareRegion;
101 		/* Number of fulltables comprising 1 spare region. */
102 	RF_StripeCount_t	  TablesPerSpareRegion;
103 		/* Number of tables. */
104 	RF_SectorCount_t	  SpareSpaceDepthPerRegionInSUs;
105 		/* Spare space/disk/region. */
106 	RF_SectorCount_t	  SpareRegionDepthInSUs;
107 		/* Number of units/disk/region. */
108 	RF_SectorNum_t		  DiskOffsetOfLastSpareSpaceChunkInSUs;
109 		/* Locates spare space after partial fulltable. */
110 	RF_StripeCount_t	  TotSparePUsPerDisk;
111 		/* Total number of spare PUs per disk. */
112 	RF_StripeCount_t	  NumCompleteSRs;
113 	RF_SpareTableEntry_t	**SpareTable;
114 		/* Remap table for spare space. */
115 	char			  sparemap_fname[RF_SPAREMAP_NAME_LEN];
116 		/* Where to find sparemap. Not used in kernel. */
117 };
118 
119 int  rf_ConfigureDeclustered(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
120 int  rf_ConfigureDeclusteredDS(RF_ShutdownList_t **, RF_Raid_t *,
121 	RF_Config_t *);
122 
123 void rf_MapSectorDeclustered(RF_Raid_t *, RF_RaidAddr_t, RF_RowCol_t *,
124 	RF_RowCol_t *, RF_SectorNum_t *, int);
125 void rf_MapParityDeclustered(RF_Raid_t *, RF_RaidAddr_t, RF_RowCol_t *,
126 	RF_RowCol_t *, RF_SectorNum_t *, int);
127 void rf_IdentifyStripeDeclustered(RF_Raid_t *, RF_RaidAddr_t, RF_RowCol_t **,
128 	RF_RowCol_t *);
129 void rf_MapSIDToPSIDDeclustered(RF_RaidLayout_t *, RF_StripeNum_t,
130 	RF_StripeNum_t *, RF_ReconUnitNum_t *);
131 int  rf_InstallSpareTable(RF_Raid_t *, RF_RowCol_t, RF_RowCol_t);
132 void rf_FreeSpareTable(RF_Raid_t *);
133 
134 RF_HeadSepLimit_t rf_GetDefaultHeadSepLimitDeclustered(RF_Raid_t *);
135 int  rf_GetDefaultNumFloatingReconBuffersDeclustered(RF_Raid_t *);
136 
137 void rf_decluster_adjust_params(RF_RaidLayout_t *, RF_StripeNum_t *,
138 	RF_StripeCount_t *, RF_StripeCount_t *, RF_StripeNum_t *);
139 void rf_remap_to_spare_space(RF_RaidLayout_t *, RF_DeclusteredConfigInfo_t *,
140 	RF_RowCol_t, RF_StripeNum_t, RF_StripeNum_t, RF_SectorNum_t,
141 	RF_StripeNum_t, RF_StripeNum_t, RF_RowCol_t *, RF_StripeNum_t *);
142 int  rf_SetSpareTable(RF_Raid_t *, void *);
143 RF_ReconUnitCount_t rf_GetNumSpareRUsDeclustered(RF_Raid_t *);
144 
145 #endif	/* ! _RF__RF_DECLUSTER_H_ */
146