rf_interdecluster.c revision 1.5.2.2 1 /* $NetBSD: rf_interdecluster.c,v 1.5.2.2 2001/11/14 19:15:49 nathanw Exp $ */
2 /*
3 * Copyright (c) 1995 Carnegie-Mellon University.
4 * All rights reserved.
5 *
6 * Author: Khalil Amiri
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 (at) 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 *
31 * rf_interdecluster.c -- implements interleaved declustering
32 *
33 ************************************************************/
34
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: rf_interdecluster.c,v 1.5.2.2 2001/11/14 19:15:49 nathanw Exp $");
37
38 #include "rf_archs.h"
39
40 #if RF_INCLUDE_INTERDECLUSTER > 0
41
42 #include <dev/raidframe/raidframevar.h>
43
44 #include "rf_raid.h"
45 #include "rf_interdecluster.h"
46 #include "rf_dag.h"
47 #include "rf_dagutils.h"
48 #include "rf_dagfuncs.h"
49 #include "rf_general.h"
50 #include "rf_utils.h"
51 #include "rf_dagffrd.h"
52 #include "rf_dagdegrd.h"
53 #include "rf_dagffwr.h"
54 #include "rf_dagdegwr.h"
55
56 typedef struct RF_InterdeclusterConfigInfo_s {
57 RF_RowCol_t **stripeIdentifier; /* filled in at config time and used
58 * by IdentifyStripe */
59 RF_StripeCount_t numSparingRegions;
60 RF_StripeCount_t stripeUnitsPerSparingRegion;
61 RF_SectorNum_t mirrorStripeOffset;
62 } RF_InterdeclusterConfigInfo_t;
63
64 int
65 rf_ConfigureInterDecluster(
66 RF_ShutdownList_t ** listp,
67 RF_Raid_t * raidPtr,
68 RF_Config_t * cfgPtr)
69 {
70 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
71 RF_StripeCount_t num_used_stripeUnitsPerDisk;
72 RF_InterdeclusterConfigInfo_t *info;
73 RF_RowCol_t i, tmp, SUs_per_region;
74
75 /* create an Interleaved Declustering configuration structure */
76 RF_MallocAndAdd(info, sizeof(RF_InterdeclusterConfigInfo_t), (RF_InterdeclusterConfigInfo_t *),
77 raidPtr->cleanupList);
78 if (info == NULL)
79 return (ENOMEM);
80 layoutPtr->layoutSpecificInfo = (void *) info;
81
82 /* fill in the config structure. */
83 SUs_per_region = raidPtr->numCol * (raidPtr->numCol - 1);
84 info->stripeIdentifier = rf_make_2d_array(SUs_per_region, 2, raidPtr->cleanupList);
85 if (info->stripeIdentifier == NULL)
86 return (ENOMEM);
87 for (i = 0; i < SUs_per_region; i++) {
88 info->stripeIdentifier[i][0] = i / (raidPtr->numCol - 1);
89 tmp = i / raidPtr->numCol;
90 info->stripeIdentifier[i][1] = (i + 1 + tmp) % raidPtr->numCol;
91 }
92
93 /* no spare tables */
94 RF_ASSERT(raidPtr->numRow == 1);
95
96 /* fill in the remaining layout parameters */
97
98 /* total number of stripes should a multiple of 2*numCol: Each sparing
99 * region consists of 2*numCol stripes: n-1 primary copy, n-1
100 * secondary copy and 2 for spare .. */
101 num_used_stripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk - (layoutPtr->stripeUnitsPerDisk %
102 (2 * raidPtr->numCol));
103 info->numSparingRegions = num_used_stripeUnitsPerDisk / (2 * raidPtr->numCol);
104 /* this is in fact the number of stripe units (that are primary data
105 * copies) in the sparing region */
106 info->stripeUnitsPerSparingRegion = raidPtr->numCol * (raidPtr->numCol - 1);
107 info->mirrorStripeOffset = info->numSparingRegions * (raidPtr->numCol + 1);
108 layoutPtr->numStripe = info->numSparingRegions * info->stripeUnitsPerSparingRegion;
109 layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector;
110 layoutPtr->numDataCol = 1;
111 layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
112 layoutPtr->numParityCol = 1;
113
114 layoutPtr->dataStripeUnitsPerDisk = num_used_stripeUnitsPerDisk;
115
116 raidPtr->sectorsPerDisk =
117 num_used_stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit;
118
119 raidPtr->totalSectors =
120 (layoutPtr->numStripe) * layoutPtr->sectorsPerStripeUnit;
121
122 layoutPtr->stripeUnitsPerDisk = raidPtr->sectorsPerDisk / layoutPtr->sectorsPerStripeUnit;
123
124 return (0);
125 }
126
127 int
128 rf_GetDefaultNumFloatingReconBuffersInterDecluster(RF_Raid_t * raidPtr)
129 {
130 return (30);
131 }
132
133 RF_HeadSepLimit_t
134 rf_GetDefaultHeadSepLimitInterDecluster(RF_Raid_t * raidPtr)
135 {
136 return (raidPtr->sectorsPerDisk);
137 }
138
139 RF_ReconUnitCount_t
140 rf_GetNumSpareRUsInterDecluster(
141 RF_Raid_t * raidPtr)
142 {
143 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
144
145 return (2 * ((RF_ReconUnitCount_t) info->numSparingRegions));
146 /* the layout uses two stripe units per disk as spare within each
147 * sparing region */
148 }
149 /* Maps to the primary copy of the data, i.e. the first mirror pair */
150 void
151 rf_MapSectorInterDecluster(
152 RF_Raid_t * raidPtr,
153 RF_RaidAddr_t raidSector,
154 RF_RowCol_t * row,
155 RF_RowCol_t * col,
156 RF_SectorNum_t * diskSector,
157 int remap)
158 {
159 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
160 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
161 RF_StripeNum_t su_offset_into_disk, mirror_su_offset_into_disk;
162 RF_StripeNum_t sparing_region_id, index_within_region;
163 int col_before_remap;
164
165 *row = 0;
166 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
167 index_within_region = SUID % info->stripeUnitsPerSparingRegion;
168 su_offset_into_disk = index_within_region % (raidPtr->numCol - 1);
169 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
170 col_before_remap = index_within_region / (raidPtr->numCol - 1);
171
172 if (!remap) {
173 *col = col_before_remap;;
174 *diskSector = (su_offset_into_disk + ((raidPtr->numCol - 1) * sparing_region_id)) *
175 raidPtr->Layout.sectorsPerStripeUnit;
176 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
177 } else {
178 /* remap sector to spare space... */
179 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit;
180 *diskSector += (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit;
181 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
182 *col = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol;
183 *col = (*col + 1) % raidPtr->numCol;
184 if (*col == col_before_remap)
185 *col = (*col + 1) % raidPtr->numCol;
186 }
187 }
188 /* Maps to the second copy of the mirror pair. */
189 void
190 rf_MapParityInterDecluster(
191 RF_Raid_t * raidPtr,
192 RF_RaidAddr_t raidSector,
193 RF_RowCol_t * row,
194 RF_RowCol_t * col,
195 RF_SectorNum_t * diskSector,
196 int remap)
197 {
198 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
199 RF_StripeNum_t sparing_region_id, index_within_region, mirror_su_offset_into_disk;
200 RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
201 int col_before_remap;
202
203 sparing_region_id = SUID / info->stripeUnitsPerSparingRegion;
204 index_within_region = SUID % info->stripeUnitsPerSparingRegion;
205 mirror_su_offset_into_disk = index_within_region / raidPtr->numCol;
206 col_before_remap = (index_within_region + 1 + mirror_su_offset_into_disk) % raidPtr->numCol;
207
208 *row = 0;
209 if (!remap) {
210 *col = col_before_remap;
211 *diskSector = info->mirrorStripeOffset * raidPtr->Layout.sectorsPerStripeUnit;
212 *diskSector += sparing_region_id * (raidPtr->numCol - 1) * raidPtr->Layout.sectorsPerStripeUnit;
213 *diskSector += mirror_su_offset_into_disk * raidPtr->Layout.sectorsPerStripeUnit;
214 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
215 } else {
216 /* remap parity to spare space ... */
217 *diskSector = sparing_region_id * (raidPtr->numCol + 1) * raidPtr->Layout.sectorsPerStripeUnit;
218 *diskSector += (raidPtr->numCol) * raidPtr->Layout.sectorsPerStripeUnit;
219 *diskSector += (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
220 *col = index_within_region / (raidPtr->numCol - 1);
221 *col = (*col + 1) % raidPtr->numCol;
222 if (*col == col_before_remap)
223 *col = (*col + 1) % raidPtr->numCol;
224 }
225 }
226
227 void
228 rf_IdentifyStripeInterDecluster(
229 RF_Raid_t * raidPtr,
230 RF_RaidAddr_t addr,
231 RF_RowCol_t ** diskids,
232 RF_RowCol_t * outRow)
233 {
234 RF_InterdeclusterConfigInfo_t *info = (RF_InterdeclusterConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
235 RF_StripeNum_t SUID;
236
237 SUID = addr / raidPtr->Layout.sectorsPerStripeUnit;
238 SUID = SUID % info->stripeUnitsPerSparingRegion;
239
240 *outRow = 0;
241 *diskids = info->stripeIdentifier[SUID];
242 }
243
244 void
245 rf_MapSIDToPSIDInterDecluster(
246 RF_RaidLayout_t * layoutPtr,
247 RF_StripeNum_t stripeID,
248 RF_StripeNum_t * psID,
249 RF_ReconUnitNum_t * which_ru)
250 {
251 *which_ru = 0;
252 *psID = stripeID;
253 }
254 /******************************************************************************
255 * select a graph to perform a single-stripe access
256 *
257 * Parameters: raidPtr - description of the physical array
258 * type - type of operation (read or write) requested
259 * asmap - logical & physical addresses for this access
260 * createFunc - name of function to use to create the graph
261 *****************************************************************************/
262
263 void
264 rf_RAIDIDagSelect(
265 RF_Raid_t * raidPtr,
266 RF_IoType_t type,
267 RF_AccessStripeMap_t * asmap,
268 RF_VoidFuncPtr * createFunc)
269 {
270 RF_ASSERT(RF_IO_IS_R_OR_W(type));
271
272 if (asmap->numDataFailed + asmap->numParityFailed > 1) {
273 RF_ERRORMSG("Multiple disks failed in a single group! Aborting I/O operation.\n");
274 *createFunc = NULL;
275 return;
276 }
277 *createFunc = (type == RF_IO_TYPE_READ) ? (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG : (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
278 if (type == RF_IO_TYPE_READ) {
279 if (asmap->numDataFailed == 0)
280 *createFunc = (RF_VoidFuncPtr) rf_CreateMirrorPartitionReadDAG;
281 else
282 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneDegradedReadDAG;
283 } else
284 *createFunc = (RF_VoidFuncPtr) rf_CreateRaidOneWriteDAG;
285 }
286 #endif /* RF_INCLUDE_INTERDECLUSTER > 0 */
287