1 /*        $NetBSD: rf_raid4.c,v 1.13 2019/02/09 03:34:00 christos Exp $         */
2 /*
3  * Copyright (c) 1995 Carnegie-Mellon University.
4  * All rights reserved.
5  *
6  * Author: Rachad Youssef
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 /***************************************
30  *
31  * rf_raid4.c -- implements RAID Level 4
32  *
33  ***************************************/
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: rf_raid4.c,v 1.13 2019/02/09 03:34:00 christos Exp $");
37 
38 #include "rf_raid.h"
39 #include "rf_dag.h"
40 #include "rf_dagutils.h"
41 #include "rf_dagfuncs.h"
42 #include "rf_dagffrd.h"
43 #include "rf_dagffwr.h"
44 #include "rf_dagdegrd.h"
45 #include "rf_dagdegwr.h"
46 #include "rf_raid4.h"
47 #include "rf_general.h"
48 
49 typedef struct RF_Raid4ConfigInfo_s {
50           RF_RowCol_t *stripeIdentifier;          /* filled in at config time & used by
51                                                    * IdentifyStripe */
52 }       RF_Raid4ConfigInfo_t;
53 
54 
55 
56 int
rf_ConfigureRAID4(RF_ShutdownList_t ** listp,RF_Raid_t * raidPtr,RF_Config_t * cfgPtr)57 rf_ConfigureRAID4(RF_ShutdownList_t **listp, RF_Raid_t *raidPtr,
58                       RF_Config_t *cfgPtr)
59 {
60           RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
61           RF_Raid4ConfigInfo_t *info;
62           int     i;
63 
64           /* create a RAID level 4 configuration structure ... */
65           info = RF_MallocAndAdd(sizeof(*info), raidPtr->cleanupList);
66           if (info == NULL)
67                     return (ENOMEM);
68           layoutPtr->layoutSpecificInfo = (void *) info;
69 
70           /* ... and fill it in. */
71           info->stripeIdentifier = RF_MallocAndAdd(raidPtr->numCol *
72               sizeof(*info->stripeIdentifier), raidPtr->cleanupList);
73           if (info->stripeIdentifier == NULL)
74                     return (ENOMEM);
75           for (i = 0; i < raidPtr->numCol; i++)
76                     info->stripeIdentifier[i] = i;
77 
78           /* fill in the remaining layout parameters */
79           layoutPtr->numStripe = layoutPtr->stripeUnitsPerDisk;
80           layoutPtr->numDataCol = raidPtr->numCol - 1;
81           layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
82           layoutPtr->numParityCol = 1;
83           raidPtr->totalSectors = layoutPtr->stripeUnitsPerDisk * layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
84 
85           return (0);
86 }
87 
88 int
rf_GetDefaultNumFloatingReconBuffersRAID4(RF_Raid_t * raidPtr)89 rf_GetDefaultNumFloatingReconBuffersRAID4(RF_Raid_t *raidPtr)
90 {
91           return (20);
92 }
93 
94 RF_HeadSepLimit_t
rf_GetDefaultHeadSepLimitRAID4(RF_Raid_t * raidPtr)95 rf_GetDefaultHeadSepLimitRAID4(RF_Raid_t *raidPtr)
96 {
97           return (20);
98 }
99 
100 void
rf_MapSectorRAID4(RF_Raid_t * raidPtr,RF_RaidAddr_t raidSector,RF_RowCol_t * col,RF_SectorNum_t * diskSector,int remap)101 rf_MapSectorRAID4(RF_Raid_t *raidPtr, RF_RaidAddr_t raidSector,
102                       RF_RowCol_t *col, RF_SectorNum_t *diskSector,
103                       int remap)
104 {
105           RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
106           *col = SUID % raidPtr->Layout.numDataCol;
107           *diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
108               (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
109 }
110 
111 void
rf_MapParityRAID4(RF_Raid_t * raidPtr,RF_RaidAddr_t raidSector,RF_RowCol_t * col,RF_SectorNum_t * diskSector,int remap)112 rf_MapParityRAID4(RF_Raid_t *raidPtr, RF_RaidAddr_t raidSector,
113                       RF_RowCol_t *col, RF_SectorNum_t *diskSector,
114                       int remap)
115 {
116           RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
117 
118           *col = raidPtr->Layout.numDataCol;
119           *diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
120               (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
121 }
122 
123 void
rf_IdentifyStripeRAID4(RF_Raid_t * raidPtr,RF_RaidAddr_t addr,RF_RowCol_t ** diskids)124 rf_IdentifyStripeRAID4(RF_Raid_t *raidPtr, RF_RaidAddr_t addr,
125                            RF_RowCol_t **diskids)
126 {
127           RF_Raid4ConfigInfo_t *info = raidPtr->Layout.layoutSpecificInfo;
128 
129           *diskids = info->stripeIdentifier;
130 }
131 
132 void
rf_MapSIDToPSIDRAID4(RF_RaidLayout_t * layoutPtr,RF_StripeNum_t stripeID,RF_StripeNum_t * psID,RF_ReconUnitNum_t * which_ru)133 rf_MapSIDToPSIDRAID4(RF_RaidLayout_t *layoutPtr,
134                          RF_StripeNum_t stripeID,
135                          RF_StripeNum_t *psID, RF_ReconUnitNum_t *which_ru)
136 {
137           *which_ru = 0;
138           *psID = stripeID;
139 }
140