/* $OpenBSD: rf_decluster.c,v 1.4 2000/08/08 16:07:40 peter Exp $ */ /* $NetBSD: rf_decluster.c,v 1.5 2000/03/07 01:54:29 oster Exp $ */ /* * Copyright (c) 1995 Carnegie-Mellon University. * All rights reserved. * * Author: Mark Holland * * Permission to use, copy, modify and distribute this software and * its documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie the * rights to redistribute these changes. */ /*---------------------------------------------------------------------- * * rf_decluster.c -- code related to the declustered layout * * Created 10-21-92 (MCH) * * Nov 93: adding support for distributed sparing. This code is a little * complex: the basic layout used is as follows: * let F = (v-1)/GCD(r,v-1). The spare space for each set of * F consecutive fulltables is grouped together and placed after * that set of tables. * +------------------------------+ * | F fulltables | * | Spare Space | * | F fulltables | * | Spare Space | * | ... | * +------------------------------+ * *--------------------------------------------------------------------*/ #include "rf_types.h" #include "rf_raid.h" #include "rf_raidframe.h" #include "rf_configure.h" #include "rf_decluster.h" #include "rf_debugMem.h" #include "rf_utils.h" #include "rf_alloclist.h" #include "rf_general.h" #include "rf_shutdown.h" extern int rf_copyback_in_progress; /* debug only */ /* found in rf_kintf.c */ int rf_GetSpareTableFromDaemon(RF_SparetWait_t * req); /* configuration code */ int rf_ConfigureDeclustered( RF_ShutdownList_t ** listp, RF_Raid_t * raidPtr, RF_Config_t * cfgPtr) { RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout); int b, v, k, r, lambda; /* block design params */ int i, j; RF_RowCol_t *first_avail_slot; RF_StripeCount_t complete_FT_count, numCompleteFullTablesPerDisk; RF_DeclusteredConfigInfo_t *info; RF_StripeCount_t PUsPerDisk, spareRegionDepthInPUs, numCompleteSpareRegionsPerDisk, extraPUsPerDisk; RF_StripeCount_t totSparePUsPerDisk; RF_SectorNum_t diskOffsetOfLastFullTableInSUs; RF_SectorCount_t SpareSpaceInSUs; char *cfgBuf = (char *) (cfgPtr->layoutSpecific); RF_StripeNum_t l, SUID; SUID = l = 0; numCompleteSpareRegionsPerDisk = 0; /* 1. create layout specific structure */ RF_MallocAndAdd(info, sizeof(RF_DeclusteredConfigInfo_t), (RF_DeclusteredConfigInfo_t *), raidPtr->cleanupList); if (info == NULL) return (ENOMEM); layoutPtr->layoutSpecificInfo = (void *) info; info->SpareTable = NULL; /* 2. extract parameters from the config structure */ if (layoutPtr->map->flags & RF_DISTRIBUTE_SPARE) { (void) bcopy(cfgBuf, info->sparemap_fname, RF_SPAREMAP_NAME_LEN); } cfgBuf += RF_SPAREMAP_NAME_LEN; b = *((int *) cfgBuf); cfgBuf += sizeof(int); v = *((int *) cfgBuf); cfgBuf += sizeof(int); k = *((int *) cfgBuf); cfgBuf += sizeof(int); r = *((int *) cfgBuf); cfgBuf += sizeof(int); lambda = *((int *) cfgBuf); cfgBuf += sizeof(int); raidPtr->noRotate = *((int *) cfgBuf); cfgBuf += sizeof(int); /* the sparemaps are generated assuming that parity is rotated, so we * issue a warning if both distributed sparing and no-rotate are on at * the same time */ if ((layoutPtr->map->flags & RF_DISTRIBUTE_SPARE) && raidPtr->noRotate) { RF_ERRORMSG("Warning: distributed sparing specified without parity rotation.\n"); } if (raidPtr->numCol != v) { RF_ERRORMSG2("RAID: config error: table element count (%d) not equal to no. of cols (%d)\n", v, raidPtr->numCol); return (EINVAL); } /* 3. set up the values used in the mapping code */ info->BlocksPerTable = b; info->Lambda = lambda; info->NumParityReps = info->groupSize = k; info->SUsPerTable = b * (k - 1) * layoutPtr->SUsPerPU; /* b blks, k-1 SUs each */ info->SUsPerFullTable = k * info->SUsPerTable; /* rot k times */ info->PUsPerBlock = k - 1; info->SUsPerBlock = info->PUsPerBlock * layoutPtr->SUsPerPU; info->TableDepthInPUs = (b * k) / v; info->FullTableDepthInPUs = info->TableDepthInPUs * k; /* k repetitions */ /* used only in distributed sparing case */ info->FullTablesPerSpareRegion = (v - 1) / rf_gcd(r, v - 1); /* (v-1)/gcd fulltables */ info->TablesPerSpareRegion = k * info->FullTablesPerSpareRegion; info->SpareSpaceDepthPerRegionInSUs = (r * info->TablesPerSpareRegion / (v - 1)) * layoutPtr->SUsPerPU; /* check to make sure the block design is sufficiently small */ if ((raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE)) { if (info->FullTableDepthInPUs * layoutPtr->SUsPerPU + info->SpareSpaceDepthPerRegionInSUs > layoutPtr->stripeUnitsPerDisk) { RF_ERRORMSG3("RAID: config error: Full Table depth (%d) + Spare Space (%d) larger than disk size (%d) (BD too big)\n", (int) info->FullTableDepthInPUs, (int) info->SpareSpaceDepthPerRegionInSUs, (int) layoutPtr->stripeUnitsPerDisk); return (EINVAL); } } else { if (info->TableDepthInPUs * layoutPtr->SUsPerPU > layoutPtr->stripeUnitsPerDisk) { RF_ERRORMSG2("RAID: config error: Table depth (%d) larger than disk size (%d) (BD too big)\n", (int) (info->TableDepthInPUs * layoutPtr->SUsPerPU), \ (int) layoutPtr->stripeUnitsPerDisk); return (EINVAL); } } /* compute the size of each disk, and the number of tables in the last * fulltable (which need not be complete) */ if (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE) { PUsPerDisk = layoutPtr->stripeUnitsPerDisk / layoutPtr->SUsPerPU; spareRegionDepthInPUs = (info->TablesPerSpareRegion * info->TableDepthInPUs + (info->TablesPerSpareRegion * info->TableDepthInPUs) / (v - 1)); info->SpareRegionDepthInSUs = spareRegionDepthInPUs * layoutPtr->SUsPerPU; numCompleteSpareRegionsPerDisk = PUsPerDisk / spareRegionDepthInPUs; info->NumCompleteSRs = numCompleteSpareRegionsPerDisk; extraPUsPerDisk = PUsPerDisk % spareRegionDepthInPUs; /* assume conservatively that we need the full amount of spare * space in one region in order to provide spares for the * partial spare region at the end of the array. We set "i" * to the number of tables in the partial spare region. This * may actually include some fulltables. */ extraPUsPerDisk -= (info->SpareSpaceDepthPerRegionInSUs / layoutPtr->SUsPerPU); if (extraPUsPerDisk <= 0) i = 0; else i = extraPUsPerDisk / info->TableDepthInPUs; complete_FT_count = raidPtr->numRow * (numCompleteSpareRegionsPerDisk * (info->TablesPerSpareRegion / k) + i / k); info->FullTableLimitSUID = complete_FT_count * info->SUsPerFullTable; info->ExtraTablesPerDisk = i % k; /* note that in the last spare region, the spare space is * complete even though data/parity space is not */ totSparePUsPerDisk = (numCompleteSpareRegionsPerDisk + 1) * (info->SpareSpaceDepthPerRegionInSUs / layoutPtr->SUsPerPU); info->TotSparePUsPerDisk = totSparePUsPerDisk; layoutPtr->stripeUnitsPerDisk = ((complete_FT_count / raidPtr->numRow) * info->FullTableDepthInPUs + /* data & parity space */ info->ExtraTablesPerDisk * info->TableDepthInPUs + totSparePUsPerDisk /* spare space */ ) * layoutPtr->SUsPerPU; layoutPtr->dataStripeUnitsPerDisk = (complete_FT_count * info->FullTableDepthInPUs + info->ExtraTablesPerDisk * info->TableDepthInPUs) * layoutPtr->SUsPerPU * (k - 1) / k; } else { /* non-dist spare case: force each disk to contain an * integral number of tables */ layoutPtr->stripeUnitsPerDisk /= (info->TableDepthInPUs * layoutPtr->SUsPerPU); layoutPtr->stripeUnitsPerDisk *= (info->TableDepthInPUs * layoutPtr->SUsPerPU); /* compute the number of tables in the last fulltable, which * need not be complete */ complete_FT_count = ((layoutPtr->stripeUnitsPerDisk / layoutPtr->SUsPerPU) / info->FullTableDepthInPUs) * raidPtr->numRow; info->FullTableLimitSUID = complete_FT_count * info->SUsPerFullTable; info->ExtraTablesPerDisk = ((layoutPtr->stripeUnitsPerDisk / layoutPtr->SUsPerPU) / info->TableDepthInPUs) % k; } raidPtr->sectorsPerDisk = layoutPtr->stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit; /* find the disk offset of the stripe unit where the last fulltable * starts */ numCompleteFullTablesPerDisk = complete_FT_count / raidPtr->numRow; diskOffsetOfLastFullTableInSUs = numCompleteFullTablesPerDisk * info->FullTableDepthInPUs * layoutPtr->SUsPerPU; if (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE) { SpareSpaceInSUs = numCompleteSpareRegionsPerDisk * info->SpareSpaceDepthPerRegionInSUs; diskOffsetOfLastFullTableInSUs += SpareSpaceInSUs; info->DiskOffsetOfLastSpareSpaceChunkInSUs = diskOffsetOfLastFullTableInSUs + info->ExtraTablesPerDisk * info->TableDepthInPUs * layoutPtr->SUsPerPU; } info->DiskOffsetOfLastFullTableInSUs = diskOffsetOfLastFullTableInSUs; info->numCompleteFullTablesPerDisk = numCompleteFullTablesPerDisk; /* 4. create and initialize the lookup tables */ info->LayoutTable = rf_make_2d_array(b, k, raidPtr->cleanupList); if (info->LayoutTable == NULL) return (ENOMEM); info->OffsetTable = rf_make_2d_array(b, k, raidPtr->cleanupList); if (info->OffsetTable == NULL) return (ENOMEM); info->BlockTable = rf_make_2d_array(info->TableDepthInPUs * layoutPtr->SUsPerPU, raidPtr->numCol, raidPtr->cleanupList); if (info->BlockTable == NULL) return (ENOMEM); first_avail_slot = rf_make_1d_array(v, NULL); if (first_avail_slot == NULL) return (ENOMEM); for (i = 0; i < b; i++) for (j = 0; j < k; j++) info->LayoutTable[i][j] = *cfgBuf++; /* initialize offset table */ for (i = 0; i < b; i++) for (j = 0; j < k; j++) { info->OffsetTable[i][j] = first_avail_slot[info->LayoutTable[i][j]]; first_avail_slot[info->LayoutTable[i][j]]++; } /* initialize block table */ for (SUID = l = 0; l < layoutPtr->SUsPerPU; l++) { for (i = 0; i < b; i++) { for (j = 0; j < k; j++) { info->BlockTable[(info->OffsetTable[i][j] * layoutPtr->SUsPerPU) + l] [info->LayoutTable[i][j]] = SUID; } SUID++; } } rf_free_1d_array(first_avail_slot, v); /* 5. set up the remaining redundant-but-useful parameters */ raidPtr->totalSectors = (k * complete_FT_count + raidPtr->numRow * info->ExtraTablesPerDisk) * info->SUsPerTable * layoutPtr->sectorsPerStripeUnit; layoutPtr->numStripe = (raidPtr->totalSectors / layoutPtr->sectorsPerStripeUnit) / (k - 1); /* strange evaluation order below to try and minimize overflow * problems */ layoutPtr->dataSectorsPerStripe = (k - 1) * layoutPtr->sectorsPerStripeUnit; layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector; layoutPtr->numDataCol = k - 1; layoutPtr->numParityCol = 1; return (0); } /* declustering with distributed sparing */ static void rf_ShutdownDeclusteredDS(RF_ThreadArg_t); static void rf_ShutdownDeclusteredDS(arg) RF_ThreadArg_t arg; { RF_DeclusteredConfigInfo_t *info; RF_Raid_t *raidPtr; raidPtr = (RF_Raid_t *) arg; info = (RF_DeclusteredConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; if (info->SpareTable) rf_FreeSpareTable(raidPtr); } int rf_ConfigureDeclusteredDS( RF_ShutdownList_t ** listp, RF_Raid_t * raidPtr, RF_Config_t * cfgPtr) { int rc; rc = rf_ConfigureDeclustered(listp, raidPtr, cfgPtr); if (rc) return (rc); rc = rf_ShutdownCreate(listp, rf_ShutdownDeclusteredDS, raidPtr); if (rc) { RF_ERRORMSG1("Got %d adding shutdown event for DeclusteredDS\n", rc); rf_ShutdownDeclusteredDS(raidPtr); return (rc); } return (0); } void rf_MapSectorDeclustered(raidPtr, raidSector, row, col, diskSector, remap) RF_Raid_t *raidPtr; RF_RaidAddr_t raidSector; RF_RowCol_t *row; RF_RowCol_t *col; RF_SectorNum_t *diskSector; int remap; { RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout); RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; RF_StripeNum_t SUID = raidSector / layoutPtr->sectorsPerStripeUnit; RF_StripeNum_t FullTableID, FullTableOffset, TableID, TableOffset; RF_StripeNum_t BlockID, BlockOffset, RepIndex; RF_StripeCount_t sus_per_fulltable = info->SUsPerFullTable; RF_StripeCount_t fulltable_depth = info->FullTableDepthInPUs * layoutPtr->SUsPerPU; RF_StripeNum_t base_suid = 0, outSU, SpareRegion = 0, SpareSpace = 0; rf_decluster_adjust_params(layoutPtr, &SUID, &sus_per_fulltable, &fulltable_depth, &base_suid); FullTableID = SUID / sus_per_fulltable; /* fulltable ID within array * (across rows) */ if (raidPtr->numRow == 1) *row = 0; /* avoid a mod and a div in the common case */ else { *row = FullTableID % raidPtr->numRow; FullTableID /= raidPtr->numRow; /* convert to fulltable ID on * this disk */ } if (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE) { SpareRegion = FullTableID / info->FullTablesPerSpareRegion; SpareSpace = SpareRegion * info->SpareSpaceDepthPerRegionInSUs; } FullTableOffset = SUID % sus_per_fulltable; TableID = FullTableOffset / info->SUsPerTable; TableOffset = FullTableOffset - TableID * info->SUsPerTable; BlockID = TableOffset / info->PUsPerBlock; BlockOffset = TableOffset - BlockID * info->PUsPerBlock; BlockID %= info->BlocksPerTable; RepIndex = info->PUsPerBlock - TableID; if (!raidPtr->noRotate) BlockOffset += ((BlockOffset >= RepIndex) ? 1 : 0); *col = info->LayoutTable[BlockID][BlockOffset]; /* remap to distributed spare space if indicated */ if (remap) { RF_ASSERT(raidPtr->Disks[*row][*col].status == rf_ds_reconstructing || raidPtr->Disks[*row][*col].status == rf_ds_dist_spared || (rf_copyback_in_progress && raidPtr->Disks[*row][*col].status == rf_ds_optimal)); rf_remap_to_spare_space(layoutPtr, info, *row, FullTableID, TableID, BlockID, (base_suid) ? 1 : 0, SpareRegion, col, &outSU); } else { outSU = base_suid; outSU += FullTableID * fulltable_depth; /* offs to strt of FT */ outSU += SpareSpace; /* skip rsvd spare space */ outSU += TableID * info->TableDepthInPUs * layoutPtr->SUsPerPU; /* offs to strt of tble */ outSU += info->OffsetTable[BlockID][BlockOffset] * layoutPtr->SUsPerPU; /* offs to the PU */ } outSU += TableOffset / (info->BlocksPerTable * info->PUsPerBlock); /* offs to the SU within * a PU */ /* convert SUs to sectors, and, if not aligned to SU boundary, add in * offset to sector. */ *diskSector = outSU * layoutPtr->sectorsPerStripeUnit + (raidSector % layoutPtr->sectorsPerStripeUnit); RF_ASSERT(*col != -1); } /* prototyping this inexplicably causes the compile of the layout table (rf_layout.c) to fail */ void rf_MapParityDeclustered( RF_Raid_t * raidPtr, RF_RaidAddr_t raidSector, RF_RowCol_t * row, RF_RowCol_t * col, RF_SectorNum_t * diskSector, int remap) { RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout); RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; RF_StripeNum_t SUID = raidSector / layoutPtr->sectorsPerStripeUnit; RF_StripeNum_t FullTableID, FullTableOffset, TableID, TableOffset; RF_StripeNum_t BlockID, BlockOffset, RepIndex; RF_StripeCount_t sus_per_fulltable = info->SUsPerFullTable; RF_StripeCount_t fulltable_depth = info->FullTableDepthInPUs * layoutPtr->SUsPerPU; RF_StripeNum_t base_suid = 0, outSU, SpareRegion = 0, SpareSpace = 0; rf_decluster_adjust_params(layoutPtr, &SUID, &sus_per_fulltable, &fulltable_depth, &base_suid); /* compute row & (possibly) spare space exactly as before */ FullTableID = SUID / sus_per_fulltable; if (raidPtr->numRow == 1) *row = 0; /* avoid a mod and a div in the common case */ else { *row = FullTableID % raidPtr->numRow; FullTableID /= raidPtr->numRow; /* convert to fulltable ID on * this disk */ } if ((raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE)) { SpareRegion = FullTableID / info->FullTablesPerSpareRegion; SpareSpace = SpareRegion * info->SpareSpaceDepthPerRegionInSUs; } /* compute BlockID and RepIndex exactly as before */ FullTableOffset = SUID % sus_per_fulltable; TableID = FullTableOffset / info->SUsPerTable; TableOffset = FullTableOffset - TableID * info->SUsPerTable; /* TableOffset = FullTableOffset % info->SUsPerTable; */ /* BlockID = (TableOffset / info->PUsPerBlock) % * info->BlocksPerTable; */ BlockID = TableOffset / info->PUsPerBlock; /* BlockOffset = TableOffset % info->PUsPerBlock; */ BlockOffset = TableOffset - BlockID * info->PUsPerBlock; BlockID %= info->BlocksPerTable; /* the parity block is in the position indicated by RepIndex */ RepIndex = (raidPtr->noRotate) ? info->PUsPerBlock : info->PUsPerBlock - TableID; *col = info->LayoutTable[BlockID][RepIndex]; if (remap) { RF_ASSERT(raidPtr->Disks[*row][*col].status == rf_ds_reconstructing || raidPtr->Disks[*row][*col].status == rf_ds_dist_spared || (rf_copyback_in_progress && raidPtr->Disks[*row][*col].status == rf_ds_optimal)); rf_remap_to_spare_space(layoutPtr, info, *row, FullTableID, TableID, BlockID, (base_suid) ? 1 : 0, SpareRegion, col, &outSU); } else { /* compute sector as before, except use RepIndex instead of * BlockOffset */ outSU = base_suid; outSU += FullTableID * fulltable_depth; outSU += SpareSpace; /* skip rsvd spare space */ outSU += TableID * info->TableDepthInPUs * layoutPtr->SUsPerPU; outSU += info->OffsetTable[BlockID][RepIndex] * layoutPtr->SUsPerPU; } outSU += TableOffset / (info->BlocksPerTable * info->PUsPerBlock); *diskSector = outSU * layoutPtr->sectorsPerStripeUnit + (raidSector % layoutPtr->sectorsPerStripeUnit); RF_ASSERT(*col != -1); } /* returns an array of ints identifying the disks that comprise the stripe containing the indicated address. * the caller must _never_ attempt to modify this array. */ void rf_IdentifyStripeDeclustered( RF_Raid_t * raidPtr, RF_RaidAddr_t addr, RF_RowCol_t ** diskids, RF_RowCol_t * outRow) { RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout); RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; RF_StripeCount_t sus_per_fulltable = info->SUsPerFullTable; RF_StripeCount_t fulltable_depth = info->FullTableDepthInPUs * layoutPtr->SUsPerPU; RF_StripeNum_t base_suid = 0; RF_StripeNum_t SUID = rf_RaidAddressToStripeUnitID(layoutPtr, addr); RF_StripeNum_t stripeID, FullTableID; int tableOffset; rf_decluster_adjust_params(layoutPtr, &SUID, &sus_per_fulltable, &fulltable_depth, &base_suid); FullTableID = SUID / sus_per_fulltable; /* fulltable ID within array * (across rows) */ *outRow = FullTableID % raidPtr->numRow; stripeID = rf_StripeUnitIDToStripeID(layoutPtr, SUID); /* find stripe offset * into array */ tableOffset = (stripeID % info->BlocksPerTable); /* find offset into * block design table */ *diskids = info->LayoutTable[tableOffset]; } /* This returns the default head-separation limit, which is measured * in "required units for reconstruction". Each time a disk fetches * a unit, it bumps a counter. The head-sep code prohibits any disk * from getting more than headSepLimit counter values ahead of any * other. * * We assume here that the number of floating recon buffers is already * set. There are r stripes to be reconstructed in each table, and so * if we have a total of B buffers, we can have at most B/r tables * under recon at any one time. In each table, lambda units are required * from each disk, so given B buffers, the head sep limit has to be * (lambda*B)/r units. We subtract one to avoid weird boundary cases. * * for example, suppose were given 50 buffers, r=19, and lambda=4 as in * the 20.5 design. There are 19 stripes/table to be reconstructed, so * we can have 50/19 tables concurrently under reconstruction, which means * we can allow the fastest disk to get 50/19 tables ahead of the slower * disk. There are lambda "required units" for each disk, so the fastest * disk can get 4*50/19 = 10 counter values ahead of the slowest. * * If numBufsToAccumulate is not 1, we need to limit the head sep further * because multiple bufs will be required for each stripe under recon. */ RF_HeadSepLimit_t rf_GetDefaultHeadSepLimitDeclustered( RF_Raid_t * raidPtr) { RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; return (info->Lambda * raidPtr->numFloatingReconBufs / info->TableDepthInPUs / rf_numBufsToAccumulate); } /* returns the default number of recon buffers to use. The value * is somewhat arbitrary...it's intended to be large enough to allow * for a reasonably large head-sep limit, but small enough that you * don't use up all your system memory with buffers. */ int rf_GetDefaultNumFloatingReconBuffersDeclustered(RF_Raid_t * raidPtr) { return (100 * rf_numBufsToAccumulate); } /* sectors in the last fulltable of the array need to be handled * specially since this fulltable can be incomplete. this function * changes the values of certain params to handle this. * * the idea here is that MapSector et. al. figure out which disk the * addressed unit lives on by computing the modulos of the unit number * with the number of units per fulltable, table, etc. In the last * fulltable, there are fewer units per fulltable, so we need to adjust * the number of user data units per fulltable to reflect this. * * so, we (1) convert the fulltable size and depth parameters to * the size of the partial fulltable at the end, (2) compute the * disk sector offset where this fulltable starts, and (3) convert * the users stripe unit number from an offset into the array to * an offset into the last fulltable. */ void rf_decluster_adjust_params( RF_RaidLayout_t * layoutPtr, RF_StripeNum_t * SUID, RF_StripeCount_t * sus_per_fulltable, RF_StripeCount_t * fulltable_depth, RF_StripeNum_t * base_suid) { RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; if (*SUID >= info->FullTableLimitSUID) { /* new full table size is size of last full table on disk */ *sus_per_fulltable = info->ExtraTablesPerDisk * info->SUsPerTable; /* new full table depth is corresponding depth */ *fulltable_depth = info->ExtraTablesPerDisk * info->TableDepthInPUs * layoutPtr->SUsPerPU; /* set up the new base offset */ *base_suid = info->DiskOffsetOfLastFullTableInSUs; /* convert users array address to an offset into the last * fulltable */ *SUID -= info->FullTableLimitSUID; } } /* * map a stripe ID to a parity stripe ID. * See comment above RaidAddressToParityStripeID in layout.c. */ void rf_MapSIDToPSIDDeclustered( RF_RaidLayout_t * layoutPtr, RF_StripeNum_t stripeID, RF_StripeNum_t * psID, RF_ReconUnitNum_t * which_ru) { RF_DeclusteredConfigInfo_t *info; info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; *psID = (stripeID / (layoutPtr->SUsPerPU * info->BlocksPerTable)) * info->BlocksPerTable + (stripeID % info->BlocksPerTable); *which_ru = (stripeID % (info->BlocksPerTable * layoutPtr->SUsPerPU)) / info->BlocksPerTable; RF_ASSERT((*which_ru) < layoutPtr->SUsPerPU / layoutPtr->SUsPerRU); } /* * Called from MapSector and MapParity to retarget an access at the spare unit. * Modifies the "col" and "outSU" parameters only. */ void rf_remap_to_spare_space( RF_RaidLayout_t * layoutPtr, RF_DeclusteredConfigInfo_t * info, RF_RowCol_t row, RF_StripeNum_t FullTableID, RF_StripeNum_t TableID, RF_SectorNum_t BlockID, RF_StripeNum_t base_suid, RF_StripeNum_t SpareRegion, RF_RowCol_t * outCol, RF_StripeNum_t * outSU) { RF_StripeNum_t ftID, spareTableStartSU, TableInSpareRegion, lastSROffset, which_ft; /* * note that FullTableID and hence SpareRegion may have gotten * tweaked by rf_decluster_adjust_params. We detect this by * noticing that base_suid is not 0. */ if (base_suid == 0) { ftID = FullTableID; } else { /* * There may be > 1.0 full tables in the last (i.e. partial) * spare region. find out which of these we're in. */ lastSROffset = info->NumCompleteSRs * info->SpareRegionDepthInSUs; which_ft = (info->DiskOffsetOfLastFullTableInSUs - lastSROffset) / (info->FullTableDepthInPUs * layoutPtr->SUsPerPU); /* compute the actual full table ID */ ftID = info->DiskOffsetOfLastFullTableInSUs / (info->FullTableDepthInPUs * layoutPtr->SUsPerPU) + which_ft; SpareRegion = info->NumCompleteSRs; } TableInSpareRegion = (ftID * info->NumParityReps + TableID) % info->TablesPerSpareRegion; *outCol = info->SpareTable[TableInSpareRegion][BlockID].spareDisk; RF_ASSERT(*outCol != -1); spareTableStartSU = (SpareRegion == info->NumCompleteSRs) ? info->DiskOffsetOfLastFullTableInSUs + info->ExtraTablesPerDisk * info->TableDepthInPUs * layoutPtr->SUsPerPU : (SpareRegion + 1) * info->SpareRegionDepthInSUs - info->SpareSpaceDepthPerRegionInSUs; *outSU = spareTableStartSU + info->SpareTable[TableInSpareRegion][BlockID].spareBlockOffsetInSUs; if (*outSU >= layoutPtr->stripeUnitsPerDisk) { printf("rf_remap_to_spare_space: invalid remapped disk SU offset %ld\n", (long) *outSU); } } int rf_InstallSpareTable( RF_Raid_t * raidPtr, RF_RowCol_t frow, RF_RowCol_t fcol) { RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; RF_SparetWait_t *req; int retcode; RF_Malloc(req, sizeof(*req), (RF_SparetWait_t *)); req->C = raidPtr->numCol; req->G = raidPtr->Layout.numDataCol + raidPtr->Layout.numParityCol; req->fcol = fcol; req->SUsPerPU = raidPtr->Layout.SUsPerPU; req->TablesPerSpareRegion = info->TablesPerSpareRegion; req->BlocksPerTable = info->BlocksPerTable; req->TableDepthInPUs = info->TableDepthInPUs; req->SpareSpaceDepthPerRegionInSUs = info->SpareSpaceDepthPerRegionInSUs; retcode = rf_GetSpareTableFromDaemon(req); RF_ASSERT(!retcode); /* XXX -- fix this to recover gracefully -- * XXX */ return (retcode); } /* * Invoked via ioctl to install a spare table in the kernel. */ int rf_SetSpareTable(raidPtr, data) RF_Raid_t *raidPtr; void *data; { RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo; RF_SpareTableEntry_t **ptrs; int i, retcode; /* what we need to copyin is a 2-d array, so first copyin the user * pointers to the rows in the table */ RF_Malloc(ptrs, info->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *), (RF_SpareTableEntry_t **)); retcode = copyin((caddr_t) data, (caddr_t) ptrs, info->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *)); if (retcode) return (retcode); /* now allocate kernel space for the row pointers */ RF_Malloc(info->SpareTable, info->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *), (RF_SpareTableEntry_t **)); /* now allocate kernel space for each row in the table, and copy it in * from user space */ for (i = 0; i < info->TablesPerSpareRegion; i++) { RF_Malloc(info->SpareTable[i], info->BlocksPerTable * sizeof(RF_SpareTableEntry_t), (RF_SpareTableEntry_t *)); retcode = copyin(ptrs[i], info->SpareTable[i], info->BlocksPerTable * sizeof(RF_SpareTableEntry_t)); if (retcode) { info->SpareTable = NULL; /* blow off the memory * we've allocated */ return (retcode); } } /* free up the temporary array we used */ RF_Free(ptrs, info->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *)); return (0); } RF_ReconUnitCount_t rf_GetNumSpareRUsDeclustered(raidPtr) RF_Raid_t *raidPtr; { RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; return (((RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo)->TotSparePUsPerDisk); } void rf_FreeSpareTable(raidPtr) RF_Raid_t *raidPtr; { long i; RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; RF_DeclusteredConfigInfo_t *info = (RF_DeclusteredConfigInfo_t *) layoutPtr->layoutSpecificInfo; RF_SpareTableEntry_t **table = info->SpareTable; for (i = 0; i < info->TablesPerSpareRegion; i++) { RF_Free(table[i], info->BlocksPerTable * sizeof(RF_SpareTableEntry_t)); } RF_Free(table, info->TablesPerSpareRegion * sizeof(RF_SpareTableEntry_t *)); info->SpareTable = (RF_SpareTableEntry_t **) NULL; }