1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
|
/* $OpenBSD: rf_interdecluster.c,v 1.4 2002/12/16 07:01:04 tdeval Exp $ */
/* $NetBSD: rf_interdecluster.c,v 1.4 2000/01/07 03:41:00 oster Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Khalil Amiri
*
* 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_interdecluster.c -- Implements interleaved declustering.
*
*************************************************************/
#include "rf_types.h"
#include "rf_raid.h"
#include "rf_interdecluster.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_general.h"
#include "rf_utils.h"
#include "rf_dagffrd.h"
#include "rf_dagdegrd.h"
#include "rf_dagffwr.h"
#include "rf_dagdegwr.h"
typedef struct RF_InterdeclusterConfigInfo_s {
/* Filled in at config time and used by IdentifyStripe. */
RF_RowCol_t **stripeIdentifier;
RF_StripeCount_t numSparingRegions;
RF_StripeCount_t stripeUnitsPerSparingRegion;
RF_SectorNum_t mirrorStripeOffset;
} RF_InterdeclusterConfigInfo_t;
int
rf_ConfigureInterDecluster(RF_ShutdownList_t **listp, RF_Raid_t *raidPtr,
RF_Config_t *cfgPtr)
{
RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
RF_StripeCount_t num_used_stripeUnitsPerDisk;
RF_InterdeclusterConfigInfo_t *info;
RF_RowCol_t i, tmp, SUs_per_region;
/* Create an Interleaved Declustering configuration structure. */
RF_MallocAndAdd(info, sizeof(RF_InterdeclusterConfigInfo_t),
(RF_InterdeclusterConfigInfo_t *), raidPtr->cleanupList);
if (info == NULL)
return (ENOMEM);
layoutPtr->layoutSpecificInfo = (void *) info;
/* Fill in the config structure. */
SUs_per_region = raidPtr->numCol * (raidPtr->numCol - 1);
info->stripeIdentifier = rf_make_2d_array(SUs_per_region, 2,
raidPtr->cleanupList);
if (info->stripeIdentifier == NULL)
return (ENOMEM);
for (i = 0; i < SUs_per_region; i++) {
info->stripeIdentifier[i][0] = i / (raidPtr->numCol - 1);
tmp = i / raidPtr->numCol;
info->stripeIdentifier[i][1] = (i + 1 + tmp) % raidPtr->numCol;
}
/* No spare tables. */
RF_ASSERT(raidPtr->numRow == 1);
/* Fill in the remaining layout parameters. */
/*
* Total number of stripes should a multiple of 2*numCol: Each sparing
* region consists of 2*numCol stripes: n-1 primary copy, n-1
* secondary copy and 2 for spare...
*/
num_used_stripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk -
(layoutPtr->stripeUnitsPerDisk % (2 * raidPtr->numCol));
info->numSparingRegions = num_used_stripeUnitsPerDisk /
(2 * raidPtr->numCol);
/*
* This is in fact the number of stripe units (that are primary data
* copies) in the sparing region.
*/
info->stripeUnitsPerSparingRegion = raidPtr->numCol *
(raidPtr->numCol - 1);
info->mirrorStripeOffset = info->numSparingRegions *
(raidPtr->numCol + 1);
layoutPtr->numStripe = info->numSparingRegions *
info->stripeUnitsPerSparingRegion;
layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit <<
raidPtr->logBytesPerSector;
layoutPtr->numDataCol = 1;
layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol *
layoutPtr->sectorsPerStripeUnit;
layoutPtr->numParityCol = 1;
layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk;
raidPtr->sectorsPerDisk =
num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit;
raidPtr->totalSectors =
(layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit;
layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk /
layoutPtr->sectorsPerStripeUnit;
return (0);
}
int
rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t *raidPtr)
{
return (30);
}
RF_HeadSepLimit_t
rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t *raidPtr)
{
return (raidPtr->sectorsPerDisk);
}
RF_ReconUnitCount_t
rf_GetNumSpareRUsInterDecluster(RF_Raid_t *raidPtr)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *)
raidPtr->Layout.layoutSpecificInfo;
return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions));
/*
* The layout uses two stripe units per disk as spare within each
* sparing region.
*/
}
/* Maps to the primary copy of the data, i.e. the first mirror pair. */
void
rf_MapSectorInterDecluster(RF_Raid_t *raidPtr, RF_RaidAddr_t raidSector,
RF_RowCol_t *row, RF_RowCol_t *col, RF_SectorNum_t* diskSector, int remap)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *)
raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk;
RF_StripeNum_t sparing_region_id, index_within_region;
int col_before_remap;
*row = 0;
sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
index_within_region = SUID % info->stripeUnitsPerSparingRegion;
su_offset_into_disk = index_within_region % (raidPtr->numCol - 1);
mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
col_before_remap = index_within_region / (raidPtr->numCol - 1);
if (!remap) {
*col = col_before_remap;
*diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) *
sparing_region_id)) * raidPtr->Layout.sectorsPerStripeUnit;
*diskSector +=
(raidSector % raidPtr->Layout.sectorsPerStripeUnit);
} else {
/* Remap sector to spare space... */
*diskSector = sparing_region_id * (raidPtr->numCol + 1) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidPtr->numCol - 1) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector +=
(raidSector % raidPtr->Layout.sectorsPerStripeUnit);
*col = (index_within_region + 1 + mirror_su_offset_into_disk) %
raidPtr->numCol;
*col = (*col + 1) % raidPtr->numCol;
if (*col == col_before_remap)
*col = (*col + 1) % raidPtr->numCol;
}
}
/* Maps to the second copy of the mirror pair. */
void
rf_MapParityInterDecluster(RF_Raid_t *raidPtr, RF_RaidAddr_t raidSector,
RF_RowCol_t *row, RF_RowCol_t *col, RF_SectorNum_t *diskSector, int remap)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *)
raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t sparing_region_id, index_within_region;
RF_StripeNum_t mirror_su_offset_into_disk;
RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
int col_before_remap;
sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
index_within_region = SUID % info->stripeUnitsPerSparingRegion;
mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
col_before_remap = (index_within_region + 1 +
mirror_su_offset_into_disk) % raidPtr->numCol;
*row = 0;
if (!remap) {
*col = col_before_remap;
*diskSector = info->mirrorStripeOffset *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += sparing_region_id * (raidPtr->numCol - 1) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += mirror_su_offset_into_disk *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector +=
(raidSector % raidPtr->Layout.sectorsPerStripeUnit);
} else {
/* Remap parity to spare space... */
*diskSector = sparing_region_id * (raidPtr->numCol + 1) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidPtr->numCol) *
raidPtr->Layout.sectorsPerStripeUnit;
*diskSector += (raidSector %
raidPtr->Layout.sectorsPerStripeUnit);
*col = index_within_region / (raidPtr->numCol - 1);
*col = (*col + 1) % raidPtr->numCol;
if (*col == col_before_remap)
*col = (*col + 1) % raidPtr->numCol;
}
}
void
rf_IdentifyStripeInterDecluster(RF_Raid_t *raidPtr, RF_RaidAddr_t addr,
RF_RowCol_t **diskids, RF_RowCol_t *outRow)
{
RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *)
raidPtr->Layout.layoutSpecificInfo;
RF_StripeNum_t SUID;
SUID = addr / raidPtr->Layout.sectorsPerStripeUnit;
SUID = SUID % info->stripeUnitsPerSparingRegion;
*outRow = 0;
*diskids = info->stripeIdentifier[SUID];
}
void
rf_MapSIDToPSIDInterDecluster( RF_RaidLayout_t *layoutPtr,
RF_StripeNum_t stripeID, RF_StripeNum_t *psID, RF_ReconUnitNum_t *which_ru)
{
*which_ru = 0;
*psID = stripeID;
}
/*****************************************************************************
* Select a graph to perform a single-stripe access.
*
* Parameters: raidPtr - Description of the physical array.
* type - Type of operation (read or write) requested.
* asmap - Logical & physical addresses for this access.
* createFunc - Name of function to use to create the graph.
*****************************************************************************/
void
rf_RAIDIDagSelect(RF_Raid_t *raidPtr, RF_IoType_t type,
RF_AccessStripeMap_t *asmap, RF_VoidFuncPtr *createFunc)
{
RF_ASSERT(RF_IO_IS_R_OR_W(type));
if (asmap->numDataFailed + asmap->numParityFailed > 1) {
RF_ERRORMSG("Multiple disks failed in a single group !"
" Aborting I/O operation.\n");
*createFunc = NULL;
return;
}
*createFunc = (type == RF_IO_TYPE_READ)
? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG
: (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
if (type == RF_IO_TYPE_READ) {
if (asmap->numDataFailed == 0)
*createFunc = (RF_VoidFuncPtr)
rf_CreateMirrorPartitionReadDAG;
else
*createFunc = (RF_VoidFuncPtr)
rf_CreateRaidOneDegradedReadDAG;
} else
*createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
}
|
