1 | /* $NetBSD: rf_raid5_rotatedspare.c,v 1.13 2009/03/14 15:36:20 dsl Exp $ */ |
2 | /* |
3 | * Copyright (c) 1995 Carnegie-Mellon University. |
4 | * All rights reserved. |
5 | * |
6 | * Author: Khalil Amiri |
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_raid5_rotated_spare.c -- implements RAID Level 5 with rotated sparing |
32 | * |
33 | **************************************************************************/ |
34 | |
35 | #include <sys/cdefs.h> |
36 | __KERNEL_RCSID(0, "$NetBSD: rf_raid5_rotatedspare.c,v 1.13 2009/03/14 15:36:20 dsl Exp $" ); |
37 | |
38 | #include "rf_archs.h" |
39 | |
40 | #if RF_INCLUDE_RAID5_RS > 0 |
41 | |
42 | #include "rf_raid.h" |
43 | #include "rf_raid5.h" |
44 | #include "rf_dag.h" |
45 | #include "rf_dagutils.h" |
46 | #include "rf_dagfuncs.h" |
47 | #include "rf_general.h" |
48 | #include "rf_utils.h" |
49 | #include "rf_raid5_rotatedspare.h" |
50 | |
51 | typedef struct RF_Raid5RSConfigInfo_s { |
52 | RF_RowCol_t **stripeIdentifier; /* filled in at config time & used by |
53 | * IdentifyStripe */ |
54 | } RF_Raid5RSConfigInfo_t; |
55 | |
56 | int |
57 | rf_ConfigureRAID5_RS( |
58 | RF_ShutdownList_t ** listp, |
59 | RF_Raid_t * raidPtr, |
60 | RF_Config_t * cfgPtr) |
61 | { |
62 | RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; |
63 | RF_Raid5RSConfigInfo_t *info; |
64 | RF_RowCol_t i, j, startdisk; |
65 | |
66 | /* create a RAID level 5 configuration structure */ |
67 | RF_MallocAndAdd(info, sizeof(RF_Raid5RSConfigInfo_t), (RF_Raid5RSConfigInfo_t *), raidPtr->cleanupList); |
68 | if (info == NULL) |
69 | return (ENOMEM); |
70 | layoutPtr->layoutSpecificInfo = (void *) info; |
71 | |
72 | RF_ASSERT(raidPtr->numCol >= 3); |
73 | |
74 | /* the stripe identifier must identify the disks in each stripe, IN |
75 | * THE ORDER THAT THEY APPEAR IN THE STRIPE. */ |
76 | info->stripeIdentifier = rf_make_2d_array(raidPtr->numCol, raidPtr->numCol, raidPtr->cleanupList); |
77 | if (info->stripeIdentifier == NULL) |
78 | return (ENOMEM); |
79 | startdisk = 0; |
80 | for (i = 0; i < raidPtr->numCol; i++) { |
81 | for (j = 0; j < raidPtr->numCol; j++) { |
82 | info->stripeIdentifier[i][j] = (startdisk + j) % raidPtr->numCol; |
83 | } |
84 | if ((--startdisk) < 0) |
85 | startdisk = raidPtr->numCol - 1; |
86 | } |
87 | |
88 | /* fill in the remaining layout parameters */ |
89 | layoutPtr->numStripe = layoutPtr->stripeUnitsPerDisk; |
90 | layoutPtr->numDataCol = raidPtr->numCol - 2; |
91 | layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit; |
92 | layoutPtr->numParityCol = 1; |
93 | layoutPtr->dataStripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk; |
94 | raidPtr->sectorsPerDisk = layoutPtr->stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit; |
95 | |
96 | raidPtr->totalSectors = layoutPtr->stripeUnitsPerDisk * layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit; |
97 | |
98 | return (0); |
99 | } |
100 | |
101 | RF_ReconUnitCount_t |
102 | rf_GetNumSpareRUsRAID5_RS(RF_Raid_t *raidPtr) |
103 | { |
104 | return (raidPtr->Layout.stripeUnitsPerDisk / raidPtr->numCol); |
105 | } |
106 | |
107 | void |
108 | rf_MapSectorRAID5_RS( |
109 | RF_Raid_t * raidPtr, |
110 | RF_RaidAddr_t raidSector, |
111 | RF_RowCol_t * col, |
112 | RF_SectorNum_t * diskSector, |
113 | int remap) |
114 | { |
115 | RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; |
116 | |
117 | if (remap) { |
118 | *col = raidPtr->numCol - 1 - (1 + SUID / raidPtr->Layout.numDataCol) % raidPtr->numCol; |
119 | *col = (*col + 1) % raidPtr->numCol; /* spare unit is rotated |
120 | * with parity; line |
121 | * above maps to parity */ |
122 | } else { |
123 | *col = (SUID + (SUID / raidPtr->Layout.numDataCol)) % raidPtr->numCol; |
124 | } |
125 | *diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit + |
126 | (raidSector % raidPtr->Layout.sectorsPerStripeUnit); |
127 | } |
128 | |
129 | void |
130 | rf_MapParityRAID5_RS( |
131 | RF_Raid_t * raidPtr, |
132 | RF_RaidAddr_t raidSector, |
133 | RF_RowCol_t * col, |
134 | RF_SectorNum_t * diskSector, |
135 | int remap) |
136 | { |
137 | RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; |
138 | |
139 | *col = raidPtr->numCol - 1 - (1 + SUID / raidPtr->Layout.numDataCol) % raidPtr->numCol; |
140 | *diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit + |
141 | (raidSector % raidPtr->Layout.sectorsPerStripeUnit); |
142 | if (remap) |
143 | *col = (*col + 1) % raidPtr->numCol; |
144 | } |
145 | |
146 | void |
147 | rf_IdentifyStripeRAID5_RS( |
148 | RF_Raid_t * raidPtr, |
149 | RF_RaidAddr_t addr, |
150 | RF_RowCol_t ** diskids) |
151 | { |
152 | RF_StripeNum_t stripeID = rf_RaidAddressToStripeID(&raidPtr->Layout, addr); |
153 | RF_Raid5RSConfigInfo_t *info = (RF_Raid5RSConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; |
154 | *diskids = info->stripeIdentifier[stripeID % raidPtr->numCol]; |
155 | |
156 | } |
157 | |
158 | void |
159 | rf_MapSIDToPSIDRAID5_RS( |
160 | RF_RaidLayout_t * layoutPtr, |
161 | RF_StripeNum_t stripeID, |
162 | RF_StripeNum_t * psID, |
163 | RF_ReconUnitNum_t * which_ru) |
164 | { |
165 | *which_ru = 0; |
166 | *psID = stripeID; |
167 | } |
168 | #endif /* RF_INCLUDE_RAID5_RS > 0 */ |
169 | |