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 | |