| 1 | /* $NetBSD: rf_reconstruct.h,v 1.28 2011/05/02 07:29:18 mrg 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 <dev/raidframe/raidframevar.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 | void *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 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 | RF_ReconBuffer_t *next; /* used for buffer management */ |
| 63 | void *arg; /* generic field for general use */ |
| 64 | RF_RowCol_t spRow, spCol; /* spare disk to which this buf should |
| 65 | * be written */ |
| 66 | /* if dist sparing off, always identifies the replacement disk */ |
| 67 | RF_SectorNum_t spOffset;/* offset into the spare disk */ |
| 68 | /* if dist sparing off, identical to failedDiskSectorOffset */ |
| 69 | RF_ReconParityStripeStatus_t *pssPtr; /* debug- pss associated with |
| 70 | * issue-pending write */ |
| 71 | }; |
| 72 | /* a reconstruction event descriptor. The event types currently are: |
| 73 | * RF_REVENT_READDONE -- a read operation has completed |
| 74 | * RF_REVENT_WRITEDONE -- a write operation has completed |
| 75 | * RF_REVENT_BUFREADY -- the buffer manager has produced a full buffer |
| 76 | * RF_REVENT_BLOCKCLEAR -- a reconstruction blockage has been cleared |
| 77 | * RF_REVENT_BUFCLEAR -- the buffer manager has released a process blocked on submission |
| 78 | * RF_REVENT_SKIP -- we need to skip the current RU and go on to the next one, typ. b/c we found recon forced |
| 79 | * RF_REVENT_FORCEDREADONE- a forced-reconstructoin read operation has completed |
| 80 | */ |
| 81 | typedef enum RF_Revent_e { |
| 82 | RF_REVENT_READDONE, |
| 83 | RF_REVENT_WRITEDONE, |
| 84 | RF_REVENT_BUFREADY, |
| 85 | RF_REVENT_BLOCKCLEAR, |
| 86 | RF_REVENT_BUFCLEAR, |
| 87 | RF_REVENT_HEADSEPCLEAR, |
| 88 | RF_REVENT_SKIP, |
| 89 | RF_REVENT_FORCEDREADDONE, |
| 90 | RF_REVENT_READ_FAILED, |
| 91 | RF_REVENT_WRITE_FAILED, |
| 92 | RF_REVENT_FORCEDREAD_FAILED |
| 93 | } RF_Revent_t; |
| 94 | |
| 95 | struct RF_ReconEvent_s { |
| 96 | RF_Revent_t type; /* what kind of event has occurred */ |
| 97 | RF_RowCol_t col; /* row ID is implicit in the queue in which |
| 98 | * the event is placed */ |
| 99 | void *arg; /* a generic argument */ |
| 100 | RF_ReconEvent_t *next; |
| 101 | }; |
| 102 | /* |
| 103 | * Reconstruction control information maintained per-disk |
| 104 | * (for surviving disks) |
| 105 | */ |
| 106 | struct RF_PerDiskReconCtrl_s { |
| 107 | RF_ReconCtrl_t *reconCtrl; |
| 108 | RF_RowCol_t col; /* to make this structure self-identifying */ |
| 109 | RF_StripeNum_t curPSID; /* the next parity stripe ID to check on this |
| 110 | * disk */ |
| 111 | RF_HeadSepLimit_t headSepCounter; /* counter used to control |
| 112 | * maximum head separation */ |
| 113 | RF_SectorNum_t diskOffset; /* the offset into the indicated disk |
| 114 | * of the current PU */ |
| 115 | RF_ReconUnitNum_t ru_count; /* this counts off the recon units |
| 116 | * within each parity unit */ |
| 117 | RF_ReconBuffer_t *rbuf; /* the recon buffer assigned to this disk */ |
| 118 | }; |
| 119 | /* main reconstruction control structure */ |
| 120 | struct RF_ReconCtrl_s { |
| 121 | RF_RaidReconDesc_t *reconDesc; |
| 122 | RF_RowCol_t fcol; /* which column has failed */ |
| 123 | RF_PerDiskReconCtrl_t *perDiskInfo; /* information maintained |
| 124 | * per-disk */ |
| 125 | RF_ReconMap_t *reconMap;/* map of what has/has not been reconstructed */ |
| 126 | RF_RowCol_t spareCol; /* which of the spare disks we're using */ |
| 127 | RF_StripeNum_t lastPSID;/* the ID of the last parity stripe we want |
| 128 | * reconstructed */ |
| 129 | int percentComplete;/* percentage completion of reconstruction */ |
| 130 | RF_ReconUnitCount_t numRUsComplete; /* number of Reconstruction Units done */ |
| 131 | RF_ReconUnitCount_t numRUsTotal; /* total number of Reconstruction Units */ |
| 132 | int error; /* non-0 indicates that an error has |
| 133 | occured during reconstruction, and |
| 134 | the reconstruction is in the process of |
| 135 | bailing out. */ |
| 136 | |
| 137 | /* reconstruction event queue */ |
| 138 | RF_ReconEvent_t *eventQueue; /* queue of pending reconstruction |
| 139 | * events */ |
| 140 | rf_declare_mutex2(eq_mutex); /* mutex for locking event */ |
| 141 | rf_declare_cond2(eq_cv); /* queue */ |
| 142 | int eq_count; /* debug only */ |
| 143 | |
| 144 | /* reconstruction buffer management */ |
| 145 | rf_declare_mutex2(rb_mutex); /* mutex/cv for messing */ |
| 146 | rf_declare_cond2(rb_cv); /* around with recon buffers */ |
| 147 | int rb_lock; /* 1 if someone is mucking |
| 148 | with recon buffers, |
| 149 | 0 otherwise */ |
| 150 | int pending_writes; /* number of writes which |
| 151 | have not completed */ |
| 152 | RF_ReconBuffer_t *floatingRbufs; /* available floating |
| 153 | * reconstruction buffers */ |
| 154 | RF_ReconBuffer_t *committedRbufs; /* recon buffers that have |
| 155 | * been committed to some |
| 156 | * waiting disk */ |
| 157 | RF_ReconBuffer_t *fullBufferList; /* full buffers waiting to be |
| 158 | * written out */ |
| 159 | RF_CallbackDesc_t *bufferWaitList; /* disks that are currently |
| 160 | * blocked waiting for buffers */ |
| 161 | |
| 162 | /* parity stripe status table */ |
| 163 | RF_PSStatusHeader_t *pssTable; /* stores the reconstruction status of |
| 164 | * active parity stripes */ |
| 165 | |
| 166 | /* maximum-head separation control */ |
| 167 | RF_HeadSepLimit_t minHeadSepCounter; /* the minimum hs counter over |
| 168 | * all disks */ |
| 169 | RF_CallbackDesc_t *headSepCBList; /* list of callbacks to be |
| 170 | * done as minPSID advances */ |
| 171 | |
| 172 | /* performance monitoring */ |
| 173 | struct timeval starttime; /* recon start time */ |
| 174 | }; |
| 175 | /* the default priority for reconstruction accesses */ |
| 176 | #define RF_IO_RECON_PRIORITY RF_IO_LOW_PRIORITY |
| 177 | |
| 178 | int rf_ConfigureReconstruction(RF_ShutdownList_t **); |
| 179 | int rf_ReconstructFailedDisk(RF_Raid_t *, RF_RowCol_t); |
| 180 | int rf_ReconstructFailedDiskBasic(RF_Raid_t *, RF_RowCol_t); |
| 181 | int rf_ReconstructInPlace(RF_Raid_t *, RF_RowCol_t); |
| 182 | int rf_ContinueReconstructFailedDisk(RF_RaidReconDesc_t *); |
| 183 | int rf_ForceOrBlockRecon(RF_Raid_t *, RF_AccessStripeMap_t *, |
| 184 | void (*cbFunc) (RF_Raid_t *, void *), |
| 185 | void *); |
| 186 | int rf_UnblockRecon(RF_Raid_t *, RF_AccessStripeMap_t *); |
| 187 | void rf_WakeupHeadSepCBWaiters(RF_Raid_t *); |
| 188 | |
| 189 | extern struct pool rf_reconbuffer_pool; |
| 190 | |
| 191 | #endif /* !_RF__RF_RECONSTRUCT_H_ */ |
| 192 | |