1 /* $NetBSD: rf_interdecluster.c,v 1.14 2006/11/16 01:33:23 christos 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 1.14 2006/11/16 01:33:23 christos 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 /* 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->numDataCol = 1; 107 layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit; 108 layoutPtr->numParityCol = 1; 109 110 layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk; 111 112 raidPtr->sectorsPerDisk = 113 num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit; 114 115 raidPtr->totalSectors = 116 (layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit; 117 118 layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk / layoutPtr->sectorsPerStripeUnit; 119 120 return (0); 121 } 122 123 int 124 rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t * raidPtr) 125 { 126 return (30); 127 } 128 129 RF_HeadSepLimit_t 130 rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t * raidPtr) 131 { 132 return (raidPtr->sectorsPerDisk); 133 } 134 135 RF_ReconUnitCount_t 136 rf_GetNumSpareRUsInterDecluster( 137 RF_Raid_t * raidPtr) 138 { 139 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 140 141 return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions)); 142 /* the layout uses two stripe units per disk as spare within each 143 * sparing region */ 144 } 145 /* Maps to the primary copy of the data, i.e. the first mirror pair */ 146 void 147 rf_MapSectorInterDecluster( 148 RF_Raid_t * raidPtr, 149 RF_RaidAddr_t raidSector, 150 RF_RowCol_t * col, 151 RF_SectorNum_t * diskSector, 152 int remap) 153 { 154 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 155 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 156 RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk; 157 RF_StripeNum_t sparing_region_id, index_within_region; 158 int col_before_remap; 159 160 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 161 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 162 su_offset_into_disk = index_within_region % (raidPtr->numCol - 1); 163 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 164 col_before_remap = index_within_region / (raidPtr->numCol - 1); 165 166 if (!remap) { 167 *col = col_before_remap; 168 *diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) * sparing_region_id)) * 169 raidPtr->Layout.sectorsPerStripeUnit; 170 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 171 } else { 172 /* remap sector to spare space... */ 173 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 174 *diskSector += (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 175 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 176 *col = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 177 *col = (*col + 1) % raidPtr->numCol; 178 if (*col == col_before_remap) 179 *col = (*col + 1) % raidPtr->numCol; 180 } 181 } 182 /* Maps to the second copy of the mirror pair. */ 183 void 184 rf_MapParityInterDecluster( 185 RF_Raid_t * raidPtr, 186 RF_RaidAddr_t raidSector, 187 RF_RowCol_t * col, 188 RF_SectorNum_t * diskSector, 189 int remap) 190 { 191 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 192 RF_StripeNum_t sparing_region_id, index_within_region, mirror_su_offset_into_disk; 193 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit; 194 int col_before_remap; 195 196 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion; 197 index_within_region = SUID % info->stripeUnitsPerSparingRegion; 198 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol; 199 col_before_remap = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol; 200 201 if (!remap) { 202 *col = col_before_remap; 203 *diskSector = info->mirrorStripeOffset * raidPtr->Layout.sectorsPerStripeUnit; 204 *diskSector += sparing_region_id * (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit; 205 *diskSector += mirror_su_offset_into_disk * raidPtr->Layout.sectorsPerStripeUnit; 206 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 207 } else { 208 /* remap parity to spare space ... */ 209 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit; 210 *diskSector += (raidPtr->numCol) * raidPtr->Layout.sectorsPerStripeUnit; 211 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit); 212 *col = index_within_region / (raidPtr->numCol - 1); 213 *col = (*col + 1) % raidPtr->numCol; 214 if (*col == col_before_remap) 215 *col = (*col + 1) % raidPtr->numCol; 216 } 217 } 218 219 void 220 rf_IdentifyStripeInterDecluster( 221 RF_Raid_t * raidPtr, 222 RF_RaidAddr_t addr, 223 RF_RowCol_t ** diskids) 224 { 225 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; 226 RF_StripeNum_t SUID; 227 228 SUID = addr / raidPtr->Layout.sectorsPerStripeUnit; 229 SUID = SUID % info->stripeUnitsPerSparingRegion; 230 231 *diskids = info->stripeIdentifier[SUID]; 232 } 233 234 void 235 rf_MapSIDToPSIDInterDecluster( 236 RF_RaidLayout_t * layoutPtr, 237 RF_StripeNum_t stripeID, 238 RF_StripeNum_t * psID, 239 RF_ReconUnitNum_t * which_ru) 240 { 241 *which_ru = 0; 242 *psID = stripeID; 243 } 244 /****************************************************************************** 245 * select a graph to perform a single-stripe access 246 * 247 * Parameters: raidPtr - description of the physical array 248 * type - type of operation (read or write) requested 249 * asmap - logical & physical addresses for this access 250 * createFunc - name of function to use to create the graph 251 *****************************************************************************/ 252 253 void 254 rf_RAIDIDagSelect( 255 RF_Raid_t * raidPtr, 256 RF_IoType_t type, 257 RF_AccessStripeMap_t * asmap, 258 RF_VoidFuncPtr * createFunc) 259 { 260 RF_ASSERT(RF_IO_IS_R_OR_W(type)); 261 262 if (asmap->numDataFailed + asmap->numParityFailed > 1) { 263 RF_ERRORMSG("Multiple disks failed in a single group! Aborting I/O operation.\n"); 264 *createFunc = NULL; 265 return; 266 } 267 *createFunc = (type == RF_IO_TYPE_READ) ? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG : (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 268 if (type == RF_IO_TYPE_READ) { 269 if (asmap->numDataFailed == 0) 270 *createFunc = (RF_VoidFuncPtr) rf_CreateMirrorPartitionReadDAG; 271 else 272 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneDegradedReadDAG; 273 } else 274 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG; 275 } 276 #endif /* RF_INCLUDE_INTERDECLUSTER > 0 */ 277