1 /* $NetBSD: rf_reconstruct.h,v 1.4 1999/03/02 03:18:48 oster Exp $ */ 2 /* 3 * Copyright (c) 1995 Carnegie-Mellon University. 4 * All rights reserved. 5 * 6 * Author: Mark Holland 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 * rf_reconstruct.h -- header file for reconstruction code 31 *********************************************************/ 32 33 #ifndef _RF__RF_RECONSTRUCT_H_ 34 #define _RF__RF_RECONSTRUCT_H_ 35 36 #include "rf_types.h" 37 #include <sys/time.h> 38 #include "rf_reconmap.h" 39 #include "rf_psstatus.h" 40 41 /* reconstruction configuration information */ 42 struct RF_ReconConfig_s { 43 unsigned numFloatingReconBufs; /* number of floating recon bufs to 44 * use */ 45 RF_HeadSepLimit_t headSepLimit; /* how far apart the heads are allow 46 * to become, in parity stripes */ 47 }; 48 /* a reconstruction buffer */ 49 struct RF_ReconBuffer_s { 50 RF_Raid_t *raidPtr; /* void * to avoid recursive includes */ 51 caddr_t buffer; /* points to the data */ 52 RF_StripeNum_t parityStripeID; /* the parity stripe that this data 53 * relates to */ 54 int which_ru; /* which reconstruction unit within the PSS */ 55 RF_SectorNum_t failedDiskSectorOffset; /* the offset into the failed 56 * disk */ 57 RF_RowCol_t row, col; /* which disk this buffer belongs to or is 58 * targeted at */ 59 RF_StripeCount_t count; /* counts the # of SUs installed so far */ 60 int priority; /* used to force hi priority recon */ 61 RF_RbufType_t type; /* FORCED or FLOATING */ 62 char *arrived; /* [x] = 1/0 if SU from disk x has/hasn't 63 * arrived */ 64 RF_ReconBuffer_t *next; /* used for buffer management */ 65 void *arg; /* generic field for general use */ 66 RF_RowCol_t spRow, spCol; /* spare disk to which this buf should 67 * be written */ 68 /* if dist sparing off, always identifies the replacement disk */ 69 RF_SectorNum_t spOffset;/* offset into the spare disk */ 70 /* if dist sparing off, identical to failedDiskSectorOffset */ 71 RF_ReconParityStripeStatus_t *pssPtr; /* debug- pss associated with 72 * issue-pending write */ 73 }; 74 /* a reconstruction event descriptor. The event types currently are: 75 * RF_REVENT_READDONE -- a read operation has completed 76 * RF_REVENT_WRITEDONE -- a write operation has completed 77 * RF_REVENT_BUFREADY -- the buffer manager has produced a full buffer 78 * RF_REVENT_BLOCKCLEAR -- a reconstruction blockage has been cleared 79 * RF_REVENT_BUFCLEAR -- the buffer manager has released a process blocked on submission 80 * RF_REVENT_SKIP -- we need to skip the current RU and go on to the next one, typ. b/c we found recon forced 81 * RF_REVENT_FORCEDREADONE- a forced-reconstructoin read operation has completed 82 */ 83 typedef enum RF_Revent_e { 84 RF_REVENT_READDONE, 85 RF_REVENT_WRITEDONE, 86 RF_REVENT_BUFREADY, 87 RF_REVENT_BLOCKCLEAR, 88 RF_REVENT_BUFCLEAR, 89 RF_REVENT_HEADSEPCLEAR, 90 RF_REVENT_SKIP, 91 RF_REVENT_FORCEDREADDONE 92 } RF_Revent_t; 93 94 struct RF_ReconEvent_s { 95 RF_Revent_t type; /* what kind of event has occurred */ 96 RF_RowCol_t col; /* row ID is implicit in the queue in which 97 * the event is placed */ 98 void *arg; /* a generic argument */ 99 RF_ReconEvent_t *next; 100 }; 101 /* 102 * Reconstruction control information maintained per-disk 103 * (for surviving disks) 104 */ 105 struct RF_PerDiskReconCtrl_s { 106 RF_ReconCtrl_t *reconCtrl; 107 RF_RowCol_t row, col; /* to make this structure self-identifying */ 108 RF_StripeNum_t curPSID; /* the next parity stripe ID to check on this 109 * disk */ 110 RF_HeadSepLimit_t headSepCounter; /* counter used to control 111 * maximum head separation */ 112 RF_SectorNum_t diskOffset; /* the offset into the indicated disk 113 * of the current PU */ 114 RF_ReconUnitNum_t ru_count; /* this counts off the recon units 115 * within each parity unit */ 116 RF_ReconBuffer_t *rbuf; /* the recon buffer assigned to this disk */ 117 }; 118 /* main reconstruction control structure */ 119 struct RF_ReconCtrl_s { 120 RF_RaidReconDesc_t *reconDesc; 121 RF_RowCol_t fcol; /* which column has failed */ 122 RF_PerDiskReconCtrl_t *perDiskInfo; /* information maintained 123 * per-disk */ 124 RF_ReconMap_t *reconMap;/* map of what has/has not been reconstructed */ 125 RF_RowCol_t spareRow; /* which of the spare disks we're using */ 126 RF_RowCol_t spareCol; 127 RF_StripeNum_t lastPSID;/* the ID of the last parity stripe we want 128 * reconstructed */ 129 int percentComplete;/* percentage completion of reconstruction */ 130 131 /* reconstruction event queue */ 132 RF_ReconEvent_t *eventQueue; /* queue of pending reconstruction 133 * events */ 134 RF_DECLARE_MUTEX(eq_mutex) /* mutex for locking event 135 * queue */ 136 RF_DECLARE_COND(eq_cond) /* condition variable for 137 * signalling recon events */ 138 int eq_count; /* debug only */ 139 140 /* reconstruction buffer management */ 141 RF_DECLARE_MUTEX(rb_mutex) /* mutex for messing around 142 * with recon buffers */ 143 RF_ReconBuffer_t *floatingRbufs; /* available floating 144 * reconstruction buffers */ 145 RF_ReconBuffer_t *committedRbufs; /* recon buffers that have 146 * been committed to some 147 * waiting disk */ 148 RF_ReconBuffer_t *fullBufferList; /* full buffers waiting to be 149 * written out */ 150 RF_ReconBuffer_t *priorityList; /* full buffers that have been 151 * elevated to higher priority */ 152 RF_CallbackDesc_t *bufferWaitList; /* disks that are currently 153 * blocked waiting for buffers */ 154 155 /* parity stripe status table */ 156 RF_PSStatusHeader_t *pssTable; /* stores the reconstruction status of 157 * active parity stripes */ 158 159 /* maximum-head separation control */ 160 RF_HeadSepLimit_t minHeadSepCounter; /* the minimum hs counter over 161 * all disks */ 162 RF_CallbackDesc_t *headSepCBList; /* list of callbacks to be 163 * done as minPSID advances */ 164 165 /* performance monitoring */ 166 struct timeval starttime; /* recon start time */ 167 168 void (*continueFunc) (void *); /* function to call when io 169 * returns */ 170 void *continueArg; /* argument for Func */ 171 }; 172 /* the default priority for reconstruction accesses */ 173 #define RF_IO_RECON_PRIORITY RF_IO_LOW_PRIORITY 174 175 int rf_ConfigureReconstruction(RF_ShutdownList_t ** listp); 176 177 int 178 rf_ReconstructFailedDisk(RF_Raid_t * raidPtr, RF_RowCol_t row, 179 RF_RowCol_t col); 180 181 int 182 rf_ReconstructFailedDiskBasic(RF_Raid_t * raidPtr, RF_RowCol_t row, 183 RF_RowCol_t col); 184 185 int 186 rf_ReconstructInPlace(RF_Raid_t * raidPtr, RF_RowCol_t row, RF_RowCol_t col); 187 188 int rf_ContinueReconstructFailedDisk(RF_RaidReconDesc_t * reconDesc); 189 190 int 191 rf_ForceOrBlockRecon(RF_Raid_t * raidPtr, RF_AccessStripeMap_t * asmap, 192 void (*cbFunc) (RF_Raid_t *, void *), void *cbArg); 193 194 int rf_UnblockRecon(RF_Raid_t * raidPtr, RF_AccessStripeMap_t * asmap); 195 196 int rf_RegisterReconDoneProc(RF_Raid_t * raidPtr, void (*proc) (RF_Raid_t *, void *), void *arg, 197 RF_ReconDoneProc_t ** handlep); 198 199 #endif /* !_RF__RF_RECONSTRUCT_H_ */ 200