1 /* $NetBSD: rf_interdecluster.c,v 1.6 2001/10/04 15:58:54 oster 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_interdecluster.c -- implements interleaved declustering 32 * 33 ************************************************************/ 34 35 #include "rf_archs.h" 36 37 #if RF_INCLUDE_INTERDECLUSTER > 0 38 39 #include <dev/raidframe/raidframevar.h> 40 41 #include "rf_raid.h" 42 #include "rf_interdecluster.h" 43 #include "rf_dag.h" 44 #include "rf_dagutils.h" 45 #include "rf_dagfuncs.h" 46 #include "rf_general.h" 47 #include "rf_utils.h" 48 #include "rf_dagffrd.h" 49 #include "rf_dagdegrd.h" 50 #include "rf_dagffwr.h" 51 #include "rf_dagdegwr.h" 52 53 typedef struct RF_InterdeclusterConfigInfo_s { 54 RF_RowCol_t **stripeIdentifier; /* filled in at config time and used 55 * by IdentifyStripe */ 56 RF_StripeCount_t numSparingRegions; 57 RF_StripeCount_t stripeUnitsPerSparingRegion; 58 RF_SectorNum_t mirrorStripeOffset; 59 } RF_InterdeclusterConfigInfo_t; 60 61 int 62 rf_ConfigureInterDecluster( 63 RF_ShutdownList_t ** listp, 64 RF_Raid_t * raidPtr, 65 RF_Config_t * cfgPtr) 66 { 67 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; 68 RF_StripeCount_t num_used_stripeUnitsPerDisk; 69 RF_InterdeclusterConfigInfo_t *info; 70 RF_RowCol_t i, tmp, SUs_per_region; 71 72 /* create an Interleaved Declustering configuration structure */ 73 RF_MallocAndAdd(info, sizeof(RF_InterdeclusterConfigInfo_t), (RF_InterdeclusterConfigInfo_t *), 74 raidPtr->cleanupList); 75 if (info == NULL) 76 return (ENOMEM); 77 layoutPtr->layoutSpecificInfo = (void *) info; 78 79 /* fill in the config structure. */ 80 SUs_per_region = raidPtr->numCol * (raidPtr->numCol - 1); 81 info->stripeIdentifier = rf_make_2d_array(SUs_per_region, 2, raidPtr->cleanupList); 82 if (info->stripeIdentifier == NULL) 83 return (ENOMEM); 84 for (i = 0; i < SUs_per_region; i++) { 85 info->stripeIdentifier[i][0] = i / (raidPtr->numCol - 1); 86 tmp = i / raidPtr->numCol; 87 info->stripeIdentifier[i][1] = (i + 1 + tmp) % raidPtr->numCol; 88 } 89 90 /* no spare tables */ 91 RF_ASSERT(raidPtr->numRow == 1); 92 93 /* fill in the remaining layout parameters */ 94 95 /* total number of stripes should a multiple of 2*numCol: Each sparing 96 * region consists of 2*numCol stripes: n-1 primary copy, n-1 97 * secondary copy and 2 for spare .. */ 98 num_used_stripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk - (layoutPtr->stripeUnitsPerDisk % 99 (2 * raidPtr->numCol)); 100 info->numSparingRegions = num_used_stripeUnitsPerDisk / (2 * raidPtr->numCol); 101 /* this is in fact the number of stripe units (that are primary data 102 * copies) in the sparing region */ 103 info->stripeUnitsPerSparingRegion = raidPtr->numCol * (raidPtr->numCol - 1); 104 info->mirrorStripeOffset = info->numSparingRegions * (raidPtr->numCol + 1); 105 layoutPtr->numStripe = info->numSparingRegions * info->stripeUnitsPerSparingRegion; 106 layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector; 107 layoutPtr->numDataCol = 1; 108 layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit; 109 layoutPtr->numParityCol = 1; 110 111 layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk; 112 113 raidPtr->sectorsPerDisk = 114 num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit; 115 116 raidPtr->totalSectors = 117 (layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit; 118 119 layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk / layoutPtr->sectorsPerStripeUnit; 120 121 return (0); 122 } 123 124 int 125 rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t * raidPtr) 126 { 127 return (30); 128 } 129 130 RF_HeadSepLimit_t 131 rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t * raidPtr) 132 { 133 return (raidPtr->sectorsPerDisk); 134 } 135 136 RF_ReconUnitCount_t 137 rf_GetNumSpareRUsInterDecluster( 138 RF_Raid_t * raidPtr) 139 { 140 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 141 142 return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions)); 143 /* the layout uses two stripe units per disk as spare within each 144 * sparing region */ 145 } 146 /* Maps to the primary copy of the data, i.e. the first mirror pair */ 147 void 148 rf_MapSectorInterDecluster( 149 RF_Raid_t * raidPtr, 150 RF_RaidAddr_t raidSector, 151 RF_RowCol_t * row, 152 RF_RowCol_t * col, 153 RF_SectorNum_t * diskSector, 154 int remap) 155 { 156 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 157 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 158 RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk; 159 RF_StripeNum_t sparing_region_id, index_within_region; 160 int col_before_remap; 161 162 *row = 0; 163 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 164 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 165 su_offset_into_disk = index_within_region % (raidPtr->numCol - 1); 166 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 167 col_before_remap = index_within_region / (raidPtr->numCol - 1); 168 169 if (!remap) { 170 *col = col_before_remap;; 171 *diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) * sparing_region_id)) * 172 raidPtr->Layout.sectorsPerStripeUnit; 173 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 174 } else { 175 /* remap sector to spare space... */ 176 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 177 *diskSector += (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 178 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 179 *col = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 180 *col = (*col + 1) % raidPtr->numCol; 181 if (*col == col_before_remap) 182 *col = (*col + 1) % raidPtr->numCol; 183 } 184 } 185 /* Maps to the second copy of the mirror pair. */ 186 void 187 rf_MapParityInterDecluster( 188 RF_Raid_t * raidPtr, 189 RF_RaidAddr_t raidSector, 190 RF_RowCol_t * row, 191 RF_RowCol_t * col, 192 RF_SectorNum_t * diskSector, 193 int remap) 194 { 195 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 196 RF_StripeNum_t sparing_region_id, index_within_region, mirror_su_offset_into_disk; 197 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 198 int col_before_remap; 199 200 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 201 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 202 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 203 col_before_remap = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 204 205 *row = 0; 206 if (!remap) { 207 *col = col_before_remap; 208 *diskSector = info->mirrorStripeOffset * raidPtr->Layout.sectorsPerStripeUnit; 209 *diskSector += sparing_region_id * (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 210 *diskSector += mirror_su_offset_into_disk * raidPtr->Layout.sectorsPerStripeUnit; 211 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 212 } else { 213 /* remap parity to spare space ... */ 214 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 215 *diskSector += (raidPtr->numCol) * raidPtr->Layout.sectorsPerStripeUnit; 216 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 217 *col = index_within_region / (raidPtr->numCol - 1); 218 *col = (*col + 1) % raidPtr->numCol; 219 if (*col == col_before_remap) 220 *col = (*col + 1) % raidPtr->numCol; 221 } 222 } 223 224 void 225 rf_IdentifyStripeInterDecluster( 226 RF_Raid_t * raidPtr, 227 RF_RaidAddr_t addr, 228 RF_RowCol_t ** diskids, 229 RF_RowCol_t * outRow) 230 { 231 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 232 RF_StripeNum_t SUID; 233 234 SUID = addr / raidPtr->Layout.sectorsPerStripeUnit; 235 SUID = SUID % info->stripeUnitsPerSparingRegion; 236 237 *outRow = 0; 238 *diskids = info->stripeIdentifier[SUID]; 239 } 240 241 void 242 rf_MapSIDToPSIDInterDecluster( 243 RF_RaidLayout_t * layoutPtr, 244 RF_StripeNum_t stripeID, 245 RF_StripeNum_t * psID, 246 RF_ReconUnitNum_t * which_ru) 247 { 248 *which_ru = 0; 249 *psID = stripeID; 250 } 251 /****************************************************************************** 252 * select a graph to perform a single-stripe access 253 * 254 * Parameters: raidPtr - description of the physical array 255 * type - type of operation (read or write) requested 256 * asmap - logical & physical addresses for this access 257 * createFunc - name of function to use to create the graph 258 *****************************************************************************/ 259 260 void 261 rf_RAIDIDagSelect( 262 RF_Raid_t * raidPtr, 263 RF_IoType_t type, 264 RF_AccessStripeMap_t * asmap, 265 RF_VoidFuncPtr * createFunc) 266 { 267 RF_ASSERT(RF_IO_IS_R_OR_W(type)); 268 269 if (asmap->numDataFailed + asmap->numParityFailed > 1) { 270 RF_ERRORMSG("Multiple disks failed in a single group! Aborting I/O operation.\n"); 271 *createFunc = NULL; 272 return; 273 } 274 *createFunc = (type == RF_IO_TYPE_READ) ? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG : (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 275 if (type == RF_IO_TYPE_READ) { 276 if (asmap->numDataFailed == 0) 277 *createFunc = (RF_VoidFuncPtr) rf_CreateMirrorPartitionReadDAG; 278 else 279 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneDegradedReadDAG; 280 } else 281 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 282 } 283 #endif /* RF_INCLUDE_INTERDECLUSTER > 0 */ 284