| 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 | |