1 /* $NetBSD: rf_interdecluster.c,v 1.8 2002/09/23 02:40:08 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 <sys/cdefs.h> 36 __KERNEL_RCSID(0, "$NetBSD: rf_interdecluster.c,v 1.8 2002/09/23 02:40:08 oster Exp $"); 37 38 #include "rf_archs.h" 39 40 #if RF_INCLUDE_INTERDECLUSTER > 0 41 42 #include <dev/raidframe/raidframevar.h> 43 44 #include "rf_raid.h" 45 #include "rf_interdecluster.h" 46 #include "rf_dag.h" 47 #include "rf_dagutils.h" 48 #include "rf_dagfuncs.h" 49 #include "rf_general.h" 50 #include "rf_utils.h" 51 #include "rf_dagffrd.h" 52 #include "rf_dagdegrd.h" 53 #include "rf_dagffwr.h" 54 #include "rf_dagdegwr.h" 55 56 typedef struct RF_InterdeclusterConfigInfo_s { 57 RF_RowCol_t **stripeIdentifier; /* filled in at config time and used 58 * by IdentifyStripe */ 59 RF_StripeCount_t numSparingRegions; 60 RF_StripeCount_t stripeUnitsPerSparingRegion; 61 RF_SectorNum_t mirrorStripeOffset; 62 } RF_InterdeclusterConfigInfo_t; 63 64 int 65 rf_ConfigureInterDecluster( 66 RF_ShutdownList_t ** listp, 67 RF_Raid_t * raidPtr, 68 RF_Config_t * cfgPtr) 69 { 70 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; 71 RF_StripeCount_t num_used_stripeUnitsPerDisk; 72 RF_InterdeclusterConfigInfo_t *info; 73 RF_RowCol_t i, tmp, SUs_per_region; 74 75 /* create an Interleaved Declustering configuration structure */ 76 RF_MallocAndAdd(info, sizeof(RF_InterdeclusterConfigInfo_t), (RF_InterdeclusterConfigInfo_t *), 77 raidPtr->cleanupList); 78 if (info == NULL) 79 return (ENOMEM); 80 layoutPtr->layoutSpecificInfo = (void *) info; 81 82 /* fill in the config structure. */ 83 SUs_per_region = raidPtr->numCol * (raidPtr->numCol - 1); 84 info->stripeIdentifier = rf_make_2d_array(SUs_per_region, 2, raidPtr->cleanupList); 85 if (info->stripeIdentifier == NULL) 86 return (ENOMEM); 87 for (i = 0; i < SUs_per_region; i++) { 88 info->stripeIdentifier[i][0] = i / (raidPtr->numCol - 1); 89 tmp = i / raidPtr->numCol; 90 info->stripeIdentifier[i][1] = (i + 1 + tmp) % raidPtr->numCol; 91 } 92 93 /* no spare tables */ 94 RF_ASSERT(raidPtr->numRow == 1); 95 96 /* fill in the remaining layout parameters */ 97 98 /* total number of stripes should a multiple of 2*numCol: Each sparing 99 * region consists of 2*numCol stripes: n-1 primary copy, n-1 100 * secondary copy and 2 for spare .. */ 101 num_used_stripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk - (layoutPtr->stripeUnitsPerDisk % 102 (2 * raidPtr->numCol)); 103 info->numSparingRegions = num_used_stripeUnitsPerDisk / (2 * raidPtr->numCol); 104 /* this is in fact the number of stripe units (that are primary data 105 * copies) in the sparing region */ 106 info->stripeUnitsPerSparingRegion = raidPtr->numCol * (raidPtr->numCol - 1); 107 info->mirrorStripeOffset = info->numSparingRegions * (raidPtr->numCol + 1); 108 layoutPtr->numStripe = info->numSparingRegions * info->stripeUnitsPerSparingRegion; 109 layoutPtr->numDataCol = 1; 110 layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit; 111 layoutPtr->numParityCol = 1; 112 113 layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk; 114 115 raidPtr->sectorsPerDisk = 116 num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit; 117 118 raidPtr->totalSectors = 119 (layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit; 120 121 layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk / layoutPtr->sectorsPerStripeUnit; 122 123 return (0); 124 } 125 126 int 127 rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t * raidPtr) 128 { 129 return (30); 130 } 131 132 RF_HeadSepLimit_t 133 rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t * raidPtr) 134 { 135 return (raidPtr->sectorsPerDisk); 136 } 137 138 RF_ReconUnitCount_t 139 rf_GetNumSpareRUsInterDecluster( 140 RF_Raid_t * raidPtr) 141 { 142 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 143 144 return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions)); 145 /* the layout uses two stripe units per disk as spare within each 146 * sparing region */ 147 } 148 /* Maps to the primary copy of the data, i.e. the first mirror pair */ 149 void 150 rf_MapSectorInterDecluster( 151 RF_Raid_t * raidPtr, 152 RF_RaidAddr_t raidSector, 153 RF_RowCol_t * row, 154 RF_RowCol_t * col, 155 RF_SectorNum_t * diskSector, 156 int remap) 157 { 158 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 159 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 160 RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk; 161 RF_StripeNum_t sparing_region_id, index_within_region; 162 int col_before_remap; 163 164 *row = 0; 165 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 166 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 167 su_offset_into_disk = index_within_region % (raidPtr->numCol - 1); 168 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 169 col_before_remap = index_within_region / (raidPtr->numCol - 1); 170 171 if (!remap) { 172 *col = col_before_remap;; 173 *diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) * sparing_region_id)) * 174 raidPtr->Layout.sectorsPerStripeUnit; 175 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 176 } else { 177 /* remap sector to spare space... */ 178 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 179 *diskSector += (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 180 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 181 *col = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 182 *col = (*col + 1) % raidPtr->numCol; 183 if (*col == col_before_remap) 184 *col = (*col + 1) % raidPtr->numCol; 185 } 186 } 187 /* Maps to the second copy of the mirror pair. */ 188 void 189 rf_MapParityInterDecluster( 190 RF_Raid_t * raidPtr, 191 RF_RaidAddr_t raidSector, 192 RF_RowCol_t * row, 193 RF_RowCol_t * col, 194 RF_SectorNum_t * diskSector, 195 int remap) 196 { 197 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 198 RF_StripeNum_t sparing_region_id, index_within_region, mirror_su_offset_into_disk; 199 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 200 int col_before_remap; 201 202 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 203 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 204 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 205 col_before_remap = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 206 207 *row = 0; 208 if (!remap) { 209 *col = col_before_remap; 210 *diskSector = info->mirrorStripeOffset * raidPtr->Layout.sectorsPerStripeUnit; 211 *diskSector += sparing_region_id * (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 212 *diskSector += mirror_su_offset_into_disk * raidPtr->Layout.sectorsPerStripeUnit; 213 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 214 } else { 215 /* remap parity to spare space ... */ 216 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 217 *diskSector += (raidPtr->numCol) * raidPtr->Layout.sectorsPerStripeUnit; 218 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 219 *col = index_within_region / (raidPtr->numCol - 1); 220 *col = (*col + 1) % raidPtr->numCol; 221 if (*col == col_before_remap) 222 *col = (*col + 1) % raidPtr->numCol; 223 } 224 } 225 226 void 227 rf_IdentifyStripeInterDecluster( 228 RF_Raid_t * raidPtr, 229 RF_RaidAddr_t addr, 230 RF_RowCol_t ** diskids, 231 RF_RowCol_t * outRow) 232 { 233 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 234 RF_StripeNum_t SUID; 235 236 SUID = addr / raidPtr->Layout.sectorsPerStripeUnit; 237 SUID = SUID % info->stripeUnitsPerSparingRegion; 238 239 *outRow = 0; 240 *diskids = info->stripeIdentifier[SUID]; 241 } 242 243 void 244 rf_MapSIDToPSIDInterDecluster( 245 RF_RaidLayout_t * layoutPtr, 246 RF_StripeNum_t stripeID, 247 RF_StripeNum_t * psID, 248 RF_ReconUnitNum_t * which_ru) 249 { 250 *which_ru = 0; 251 *psID = stripeID; 252 } 253 /****************************************************************************** 254 * select a graph to perform a single-stripe access 255 * 256 * Parameters: raidPtr - description of the physical array 257 * type - type of operation (read or write) requested 258 * asmap - logical & physical addresses for this access 259 * createFunc - name of function to use to create the graph 260 *****************************************************************************/ 261 262 void 263 rf_RAIDIDagSelect( 264 RF_Raid_t * raidPtr, 265 RF_IoType_t type, 266 RF_AccessStripeMap_t * asmap, 267 RF_VoidFuncPtr * createFunc) 268 { 269 RF_ASSERT(RF_IO_IS_R_OR_W(type)); 270 271 if (asmap->numDataFailed + asmap->numParityFailed > 1) { 272 RF_ERRORMSG("Multiple disks failed in a single group! Aborting I/O operation.\n"); 273 *createFunc = NULL; 274 return; 275 } 276 *createFunc = (type == RF_IO_TYPE_READ) ? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG : (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 277 if (type == RF_IO_TYPE_READ) { 278 if (asmap->numDataFailed == 0) 279 *createFunc = (RF_VoidFuncPtr) rf_CreateMirrorPartitionReadDAG; 280 else 281 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneDegradedReadDAG; 282 } else 283 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 284 } 285 #endif /* RF_INCLUDE_INTERDECLUSTER > 0 */ 286