1/* $NetBSD: rf_dagdegwr.c,v 1.33 2014/03/23 03:42:39 christos Exp $ */
2/*
3 * Copyright (c) 1995 Carnegie-Mellon University.
4 * All rights reserved.
5 *
6 * Author: Mark Holland, Daniel Stodolsky, William V. Courtright II
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_dagdegwr.c
31 *
32 * code for creating degraded write DAGs
33 *
34 */
35
36#include <sys/cdefs.h>
37__KERNEL_RCSID(0, "$NetBSD: rf_dagdegwr.c,v 1.33 2014/03/23 03:42:39 christos Exp $");
38
39#include <dev/raidframe/raidframevar.h>
40
41#include "rf_raid.h"
42#include "rf_dag.h"
43#include "rf_dagutils.h"
44#include "rf_dagfuncs.h"
45#include "rf_debugMem.h"
46#include "rf_general.h"
47#include "rf_dagdegwr.h"
48#include "rf_map.h"
49
50
51/******************************************************************************
52 *
53 * General comments on DAG creation:
54 *
55 * All DAGs in this file use roll-away error recovery. Each DAG has a single
56 * commit node, usually called "Cmt." If an error occurs before the Cmt node
57 * is reached, the execution engine will halt forward execution and work
58 * backward through the graph, executing the undo functions. Assuming that
59 * each node in the graph prior to the Cmt node are undoable and atomic - or -
60 * does not make changes to permanent state, the graph will fail atomically.
61 * If an error occurs after the Cmt node executes, the engine will roll-forward
62 * through the graph, blindly executing nodes until it reaches the end.
63 * If a graph reaches the end, it is assumed to have completed successfully.
64 *
65 * A graph has only 1 Cmt node.
66 *
67 */
68
69
70/******************************************************************************
71 *
72 * The following wrappers map the standard DAG creation interface to the
73 * DAG creation routines. Additionally, these wrappers enable experimentation
74 * with new DAG structures by providing an extra level of indirection, allowing
75 * the DAG creation routines to be replaced at this single point.
76 */
77
78static
79RF_CREATE_DAG_FUNC_DECL(rf_CreateSimpleDegradedWriteDAG)
80{
81 rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp,
82 flags, allocList, 1, rf_RecoveryXorFunc, RF_TRUE);
83}
84
85void
86rf_CreateDegradedWriteDAG(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
87 RF_DagHeader_t *dag_h, void *bp,
88 RF_RaidAccessFlags_t flags,
89 RF_AllocListElem_t *allocList)
90{
91
92 RF_ASSERT(asmap->numDataFailed == 1);
93 dag_h->creator = "DegradedWriteDAG";
94
95 /*
96 * if the access writes only a portion of the failed unit, and also
97 * writes some portion of at least one surviving unit, we create two
98 * DAGs, one for the failed component and one for the non-failed
99 * component, and do them sequentially. Note that the fact that we're
100 * accessing only a portion of the failed unit indicates that the
101 * access either starts or ends in the failed unit, and hence we need
102 * create only two dags. This is inefficient in that the same data or
103 * parity can get read and written twice using this structure. I need
104 * to fix this to do the access all at once.
105 */
106 RF_ASSERT(!(asmap->numStripeUnitsAccessed != 1 &&
107 asmap->failedPDAs[0]->numSector !=
108 raidPtr->Layout.sectorsPerStripeUnit));
109 rf_CreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags,
110 allocList);
111}
112
113
114
115/******************************************************************************
116 *
117 * DAG creation code begins here
118 */
119
120
121
122/******************************************************************************
123 *
124 * CommonCreateSimpleDegradedWriteDAG -- creates a DAG to do a degraded-mode
125 * write, which is as follows
126 *
127 * / {Wnq} --\
128 * hdr -> blockNode -> Rod -> Xor -> Cmt -> Wnp ----> unblock -> term
129 * \ {Rod} / \ Wnd ---/
130 * \ {Wnd} -/
131 *
132 * commit nodes: Xor, Wnd
133 *
134 * IMPORTANT:
135 * This DAG generator does not work for double-degraded archs since it does not
136 * generate Q
137 *
138 * This dag is essentially identical to the large-write dag, except that the
139 * write to the failed data unit is suppressed.
140 *
141 * IMPORTANT: this dag does not work in the case where the access writes only
142 * a portion of the failed unit, and also writes some portion of at least one
143 * surviving SU. this case is handled in CreateDegradedWriteDAG above.
144 *
145 * The block & unblock nodes are leftovers from a previous version. They
146 * do nothing, but I haven't deleted them because it would be a tremendous
147 * effort to put them back in.
148 *
149 * This dag is used whenever a one of the data units in a write has failed.
150 * If it is the parity unit that failed, the nonredundant write dag (below)
151 * is used.
152 *****************************************************************************/
153
154void
155rf_CommonCreateSimpleDegradedWriteDAG(RF_Raid_t *raidPtr,
156 RF_AccessStripeMap_t *asmap,
157 RF_DagHeader_t *dag_h, void *bp,
158 RF_RaidAccessFlags_t flags,
159 RF_AllocListElem_t *allocList,
160 int nfaults,
161 int (*redFunc) (RF_DagNode_t *),
162 int allowBufferRecycle)
163{
164 int nRrdNodes, nWndNodes, nXorBufs, i, j, paramNum,
165 rdnodesFaked;
166 RF_DagNode_t *blockNode, *unblockNode, *wnpNode, *termNode;
167#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
168 RF_DagNode_t *wnqNode;
169#endif
170 RF_DagNode_t *wndNodes, *rrdNodes, *xorNode, *commitNode;
171 RF_DagNode_t *tmpNode, *tmpwndNode, *tmprrdNode;
172 RF_SectorCount_t sectorsPerSU;
173 RF_ReconUnitNum_t which_ru;
174 char *xorTargetBuf = NULL; /* the target buffer for the XOR
175 * operation */
176 char overlappingPDAs[RF_MAXCOL];/* a temporary array of flags */
177 RF_AccessStripeMapHeader_t *new_asm_h[2];
178 RF_PhysDiskAddr_t *pda, *parityPDA;
179 RF_StripeNum_t parityStripeID;
180 RF_PhysDiskAddr_t *failedPDA;
181 RF_RaidLayout_t *layoutPtr;
182
183 layoutPtr = &(raidPtr->Layout);
184 parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr, asmap->raidAddress,
185 &which_ru);
186 sectorsPerSU = layoutPtr->sectorsPerStripeUnit;
187 /* failedPDA points to the pda within the asm that targets the failed
188 * disk */
189 failedPDA = asmap->failedPDAs[0];
190
191#if RF_DEBUG_DAG
192 if (rf_dagDebug)
193 printf("[Creating degraded-write DAG]\n");
194#endif
195
196 RF_ASSERT(asmap->numDataFailed == 1);
197 dag_h->creator = "SimpleDegradedWriteDAG";
198
199 /*
200 * Generate two ASMs identifying the surviving data
201 * we need in order to recover the lost data.
202 */
203 /* overlappingPDAs array must be zero'd */
204 memset(overlappingPDAs, 0, RF_MAXCOL);
205 rf_GenerateFailedAccessASMs(raidPtr, asmap, failedPDA, dag_h, new_asm_h,
206 &nXorBufs, NULL, overlappingPDAs, allocList);
207
208 /* create all the nodes at once */
209 nWndNodes = asmap->numStripeUnitsAccessed - 1; /* no access is
210 * generated for the
211 * failed pda */
212
213 nRrdNodes = ((new_asm_h[0]) ? new_asm_h[0]->stripeMap->numStripeUnitsAccessed : 0) +
214 ((new_asm_h[1]) ? new_asm_h[1]->stripeMap->numStripeUnitsAccessed : 0);
215 /*
216 * XXX
217 *
218 * There's a bug with a complete stripe overwrite- that means 0 reads
219 * of old data, and the rest of the DAG generation code doesn't like
220 * that. A release is coming, and I don't wanna risk breaking a critical
221 * DAG generator, so here's what I'm gonna do- if there's no read nodes,
222 * I'm gonna fake there being a read node, and I'm gonna swap in a
223 * no-op node in its place (to make all the link-up code happy).
224 * This should be fixed at some point. --jimz
225 */
226 if (nRrdNodes == 0) {
227 nRrdNodes = 1;
228 rdnodesFaked = 1;
229 } else {
230 rdnodesFaked = 0;
231 }
232
233 blockNode = rf_AllocDAGNode();
234 blockNode->list_next = dag_h->nodes;
235 dag_h->nodes = blockNode;
236
237 commitNode = rf_AllocDAGNode();
238 commitNode->list_next = dag_h->nodes;
239 dag_h->nodes = commitNode;
240
241 unblockNode = rf_AllocDAGNode();
242 unblockNode->list_next = dag_h->nodes;
243 dag_h->nodes = unblockNode;
244
245 termNode = rf_AllocDAGNode();
246 termNode->list_next = dag_h->nodes;
247 dag_h->nodes = termNode;
248
249 xorNode = rf_AllocDAGNode();
250 xorNode->list_next = dag_h->nodes;
251 dag_h->nodes = xorNode;
252
253 wnpNode = rf_AllocDAGNode();
254 wnpNode->list_next = dag_h->nodes;
255 dag_h->nodes = wnpNode;
256
257 for (i = 0; i < nWndNodes; i++) {
258 tmpNode = rf_AllocDAGNode();
259 tmpNode->list_next = dag_h->nodes;
260 dag_h->nodes = tmpNode;
261 }
262 wndNodes = dag_h->nodes;
263
264 for (i = 0; i < nRrdNodes; i++) {
265 tmpNode = rf_AllocDAGNode();
266 tmpNode->list_next = dag_h->nodes;
267 dag_h->nodes = tmpNode;
268 }
269 rrdNodes = dag_h->nodes;
270
271#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
272 if (nfaults == 2) {
273 wnqNode = rf_AllocDAGNode();
274 wnqNode->list_next = dag_h->nodes;
275 dag_h->nodes = wnqNode;
276 } else {
277 wnqNode = NULL;
278 }
279#endif
280
281 /* this dag can not commit until all rrd and xor Nodes have completed */
282 dag_h->numCommitNodes = 1;
283 dag_h->numCommits = 0;
284 dag_h->numSuccedents = 1;
285
286 RF_ASSERT(nRrdNodes > 0);
287 rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
288 NULL, nRrdNodes, 0, 0, 0, dag_h, "Nil", allocList);
289 rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
290 NULL, nWndNodes + nfaults, 1, 0, 0, dag_h, "Cmt", allocList);
291 rf_InitNode(unblockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
292 NULL, 1, nWndNodes + nfaults, 0, 0, dag_h, "Nil", allocList);
293 rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc,
294 NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
295 rf_InitNode(xorNode, rf_wait, RF_FALSE, redFunc, rf_NullNodeUndoFunc, NULL, 1,
296 nRrdNodes, 2 * nXorBufs + 2, nfaults, dag_h, "Xrc", allocList);
297
298 /*
299 * Fill in the Rrd nodes. If any of the rrd buffers are the same size as
300 * the failed buffer, save a pointer to it so we can use it as the target
301 * of the XOR. The pdas in the rrd nodes have been range-restricted, so if
302 * a buffer is the same size as the failed buffer, it must also be at the
303 * same alignment within the SU.
304 */
305 i = 0;
306 tmprrdNode = rrdNodes;
307 if (new_asm_h[0]) {
308 for (i = 0, pda = new_asm_h[0]->stripeMap->physInfo;
309 i < new_asm_h[0]->stripeMap->numStripeUnitsAccessed;
310 i++, pda = pda->next) {
311 rf_InitNode(tmprrdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
312 rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rrd", allocList);
313 RF_ASSERT(pda);
314 tmprrdNode->params[0].p = pda;
315 tmprrdNode->params[1].p = pda->bufPtr;
316 tmprrdNode->params[2].v = parityStripeID;
317 tmprrdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
318 tmprrdNode = tmprrdNode->list_next;
319 }
320 }
321 /* i now equals the number of stripe units accessed in new_asm_h[0] */
322 /* Note that for tmprrdNode, this means a continuation from above, so no need to
323 assign it anything.. */
324 if (new_asm_h[1]) {
325 for (j = 0, pda = new_asm_h[1]->stripeMap->physInfo;
326 j < new_asm_h[1]->stripeMap->numStripeUnitsAccessed;
327 j++, pda = pda->next) {
328 rf_InitNode(tmprrdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
329 rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rrd", allocList);
330 RF_ASSERT(pda);
331 tmprrdNode->params[0].p = pda;
332 tmprrdNode->params[1].p = pda->bufPtr;
333 tmprrdNode->params[2].v = parityStripeID;
334 tmprrdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
335 if (allowBufferRecycle && (pda->numSector == failedPDA->numSector))
336 xorTargetBuf = pda->bufPtr;
337 tmprrdNode = tmprrdNode->list_next;
338 }
339 }
340 if (rdnodesFaked) {
341 /*
342 * This is where we'll init that fake noop read node
343 * (XXX should the wakeup func be different?)
344 */
345 /* node that rrdNodes will just be a single node... */
346 rf_InitNode(rrdNodes, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
347 NULL, 1, 1, 0, 0, dag_h, "RrN", allocList);
348 }
349 /*
350 * Make a PDA for the parity unit. The parity PDA should start at
351 * the same offset into the SU as the failed PDA.
352 */
353 /* Danner comment: I don't think this copy is really necessary. We are
354 * in one of two cases here. (1) The entire failed unit is written.
355 * Then asmap->parityInfo will describe the entire parity. (2) We are
356 * only writing a subset of the failed unit and nothing else. Then the
357 * asmap->parityInfo describes the failed unit and the copy can also
358 * be avoided. */
359
360 parityPDA = rf_AllocPhysDiskAddr();
361 parityPDA->next = dag_h->pda_cleanup_list;
362 dag_h->pda_cleanup_list = parityPDA;
363 parityPDA->col = asmap->parityInfo->col;
364 parityPDA->startSector = ((asmap->parityInfo->startSector / sectorsPerSU)
365 * sectorsPerSU) + (failedPDA->startSector % sectorsPerSU);
366 parityPDA->numSector = failedPDA->numSector;
367
368 if (!xorTargetBuf) {
369 xorTargetBuf = rf_AllocBuffer(raidPtr, dag_h, rf_RaidAddressToByte(raidPtr, failedPDA->numSector));
370 }
371 /* init the Wnp node */
372 rf_InitNode(wnpNode, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
373 rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnp", allocList);
374 wnpNode->params[0].p = parityPDA;
375 wnpNode->params[1].p = xorTargetBuf;
376 wnpNode->params[2].v = parityStripeID;
377 wnpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
378
379#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
380 /* fill in the Wnq Node */
381 if (nfaults == 2) {
382 {
383 RF_MallocAndAdd(parityPDA, sizeof(RF_PhysDiskAddr_t),
384 (RF_PhysDiskAddr_t *), allocList);
385 parityPDA->col = asmap->qInfo->col;
386 parityPDA->startSector = ((asmap->qInfo->startSector / sectorsPerSU)
387 * sectorsPerSU) + (failedPDA->startSector % sectorsPerSU);
388 parityPDA->numSector = failedPDA->numSector;
389
390 rf_InitNode(wnqNode, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
391 rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnq", allocList);
392 wnqNode->params[0].p = parityPDA;
393 RF_MallocAndAdd(xorNode->results[1],
394 rf_RaidAddressToByte(raidPtr, failedPDA->numSector), (char *), allocList);
395 wnqNode->params[1].p = xorNode->results[1];
396 wnqNode->params[2].v = parityStripeID;
397 wnqNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
398 }
399 }
400#endif
401 /* fill in the Wnd nodes */
402 tmpwndNode = wndNodes;
403 for (pda = asmap->physInfo, i = 0; i < nWndNodes; i++, pda = pda->next) {
404 if (pda == failedPDA) {
405 i--;
406 continue;
407 }
408 rf_InitNode(tmpwndNode, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
409 rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnd", allocList);
410 RF_ASSERT(pda);
411 tmpwndNode->params[0].p = pda;
412 tmpwndNode->params[1].p = pda->bufPtr;
413 tmpwndNode->params[2].v = parityStripeID;
414 tmpwndNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
415 tmpwndNode = tmpwndNode->list_next;
416 }
417
418 /* fill in the results of the xor node */
419 xorNode->results[0] = xorTargetBuf;
420
421 /* fill in the params of the xor node */
422
423 paramNum = 0;
424 if (rdnodesFaked == 0) {
425 tmprrdNode = rrdNodes;
426 for (i = 0; i < nRrdNodes; i++) {
427 /* all the Rrd nodes need to be xored together */
428 xorNode->params[paramNum++] = tmprrdNode->params[0];
429 xorNode->params[paramNum++] = tmprrdNode->params[1];
430 tmprrdNode = tmprrdNode->list_next;
431 }
432 }
433 tmpwndNode = wndNodes;
434 for (i = 0; i < nWndNodes; i++) {
435 /* any Wnd nodes that overlap the failed access need to be
436 * xored in */
437 if (overlappingPDAs[i]) {
438 pda = rf_AllocPhysDiskAddr();
439 memcpy((char *) pda, (char *) tmpwndNode->params[0].p, sizeof(RF_PhysDiskAddr_t));
440 /* add it into the pda_cleanup_list *after* the copy, TYVM */
441 pda->next = dag_h->pda_cleanup_list;
442 dag_h->pda_cleanup_list = pda;
443 rf_RangeRestrictPDA(raidPtr, failedPDA, pda, RF_RESTRICT_DOBUFFER, 0);
444 xorNode->params[paramNum++].p = pda;
445 xorNode->params[paramNum++].p = pda->bufPtr;
446 }
447 tmpwndNode = tmpwndNode->list_next;
448 }
449
450 /*
451 * Install the failed PDA into the xor param list so that the
452 * new data gets xor'd in.
453 */
454 xorNode->params[paramNum++].p = failedPDA;
455 xorNode->params[paramNum++].p = failedPDA->bufPtr;
456
457 /*
458 * The last 2 params to the recovery xor node are always the failed
459 * PDA and the raidPtr. install the failedPDA even though we have just
460 * done so above. This allows us to use the same XOR function for both
461 * degraded reads and degraded writes.
462 */
463 xorNode->params[paramNum++].p = failedPDA;
464 xorNode->params[paramNum++].p = raidPtr;
465 RF_ASSERT(paramNum == 2 * nXorBufs + 2);
466
467 /*
468 * Code to link nodes begins here
469 */
470
471 /* link header to block node */
472 RF_ASSERT(blockNode->numAntecedents == 0);
473 dag_h->succedents[0] = blockNode;
474
475 /* link block node to rd nodes */
476 RF_ASSERT(blockNode->numSuccedents == nRrdNodes);
477 tmprrdNode = rrdNodes;
478 for (i = 0; i < nRrdNodes; i++) {
479 RF_ASSERT(tmprrdNode->numAntecedents == 1);
480 blockNode->succedents[i] = tmprrdNode;
481 tmprrdNode->antecedents[0] = blockNode;
482 tmprrdNode->antType[0] = rf_control;
483 tmprrdNode = tmprrdNode->list_next;
484 }
485
486 /* link read nodes to xor node */
487 RF_ASSERT(xorNode->numAntecedents == nRrdNodes);
488 tmprrdNode = rrdNodes;
489 for (i = 0; i < nRrdNodes; i++) {
490 RF_ASSERT(tmprrdNode->numSuccedents == 1);
491 tmprrdNode->succedents[0] = xorNode;
492 xorNode->antecedents[i] = tmprrdNode;
493 xorNode->antType[i] = rf_trueData;
494 tmprrdNode = tmprrdNode->list_next;
495 }
496
497 /* link xor node to commit node */
498 RF_ASSERT(xorNode->numSuccedents == 1);
499 RF_ASSERT(commitNode->numAntecedents == 1);
500 xorNode->succedents[0] = commitNode;
501 commitNode->antecedents[0] = xorNode;
502 commitNode->antType[0] = rf_control;
503
504 /* link commit node to wnd nodes */
505 RF_ASSERT(commitNode->numSuccedents == nfaults + nWndNodes);
506 tmpwndNode = wndNodes;
507 for (i = 0; i < nWndNodes; i++) {
508 RF_ASSERT(tmpwndNode->numAntecedents == 1);
509 commitNode->succedents[i] = tmpwndNode;
510 tmpwndNode->antecedents[0] = commitNode;
511 tmpwndNode->antType[0] = rf_control;
512 tmpwndNode = tmpwndNode->list_next;
513 }
514
515 /* link the commit node to wnp, wnq nodes */
516 RF_ASSERT(wnpNode->numAntecedents == 1);
517 commitNode->succedents[nWndNodes] = wnpNode;
518 wnpNode->antecedents[0] = commitNode;
519 wnpNode->antType[0] = rf_control;
520#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
521 if (nfaults == 2) {
522 RF_ASSERT(wnqNode->numAntecedents == 1);
523 commitNode->succedents[nWndNodes + 1] = wnqNode;
524 wnqNode->antecedents[0] = commitNode;
525 wnqNode->antType[0] = rf_control;
526 }
527#endif
528 /* link write new data nodes to unblock node */
529 RF_ASSERT(unblockNode->numAntecedents == (nWndNodes + nfaults));
530 tmpwndNode = wndNodes;
531 for (i = 0; i < nWndNodes; i++) {
532 RF_ASSERT(tmpwndNode->numSuccedents == 1);
533 tmpwndNode->succedents[0] = unblockNode;
534 unblockNode->antecedents[i] = tmpwndNode;
535 unblockNode->antType[i] = rf_control;
536 tmpwndNode = tmpwndNode->list_next;
537 }
538
539 /* link write new parity node to unblock node */
540 RF_ASSERT(wnpNode->numSuccedents == 1);
541 wnpNode->succedents[0] = unblockNode;
542 unblockNode->antecedents[nWndNodes] = wnpNode;
543 unblockNode->antType[nWndNodes] = rf_control;
544
545#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
546 /* link write new q node to unblock node */
547 if (nfaults == 2) {
548 RF_ASSERT(wnqNode->numSuccedents == 1);
549 wnqNode->succedents[0] = unblockNode;
550 unblockNode->antecedents[nWndNodes + 1] = wnqNode;
551 unblockNode->antType[nWndNodes + 1] = rf_control;
552 }
553#endif
554 /* link unblock node to term node */
555 RF_ASSERT(unblockNode->numSuccedents == 1);
556 RF_ASSERT(termNode->numAntecedents == 1);
557 RF_ASSERT(termNode->numSuccedents == 0);
558 unblockNode->succedents[0] = termNode;
559 termNode->antecedents[0] = unblockNode;
560 termNode->antType[0] = rf_control;
561}
562#define CONS_PDA(if,start,num) \
563 pda_p->col = asmap->if->col; \
564 pda_p->startSector = ((asmap->if->startSector / secPerSU) * secPerSU) + start; \
565 pda_p->numSector = num; \
566 pda_p->next = NULL; \
567 RF_MallocAndAdd(pda_p->bufPtr,rf_RaidAddressToByte(raidPtr,num),(char *), allocList)
568#if (RF_INCLUDE_PQ > 0) || (RF_INCLUDE_EVENODD > 0)
569void
570rf_WriteGenerateFailedAccessASMs(
571 RF_Raid_t * raidPtr,
572 RF_AccessStripeMap_t * asmap,
573 RF_PhysDiskAddr_t ** pdap,
574 int *nNodep,
575 RF_PhysDiskAddr_t ** pqpdap,
576 int *nPQNodep,
577 RF_AllocListElem_t * allocList)
578{
579 RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
580 int PDAPerDisk, i;
581 RF_SectorCount_t secPerSU = layoutPtr->sectorsPerStripeUnit;
582 int numDataCol = layoutPtr->numDataCol;
583 int state;
584 unsigned napdas;
585 RF_SectorNum_t fone_start, ftwo_start = 0;
586 RF_PhysDiskAddr_t *fone = asmap->failedPDAs[0], *ftwo = asmap->failedPDAs[1];
587 RF_PhysDiskAddr_t *pda_p;
588 RF_RaidAddr_t sosAddr;
589
590 /* determine how many pda's we will have to generate per unaccess
591 * stripe. If there is only one failed data unit, it is one; if two,
592 * possibly two, depending whether they overlap. */
593
594 fone_start = rf_StripeUnitOffset(layoutPtr, fone->startSector);
595
596 if (asmap->numDataFailed == 1) {
597 PDAPerDisk = 1;
598 state = 1;
599 RF_MallocAndAdd(*pqpdap, 2 * sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t *), allocList);
600 pda_p = *pqpdap;
601 /* build p */
602 CONS_PDA(parityInfo, fone_start, fone->numSector);
603 pda_p->type = RF_PDA_TYPE_PARITY;
604 pda_p++;
605 /* build q */
606 CONS_PDA(qInfo, fone_start, fone->numSector);
607 pda_p->type = RF_PDA_TYPE_Q;
608 } else {
609 ftwo_start = rf_StripeUnitOffset(layoutPtr, ftwo->startSector);
610 if (fone->numSector + ftwo->numSector > secPerSU) {
611 PDAPerDisk = 1;
612 state = 2;
613 RF_MallocAndAdd(*pqpdap, 2 * sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t *), allocList);
614 pda_p = *pqpdap;
615 CONS_PDA(parityInfo, 0, secPerSU);
616 pda_p->type = RF_PDA_TYPE_PARITY;
617 pda_p++;
618 CONS_PDA(qInfo, 0, secPerSU);
619 pda_p->type = RF_PDA_TYPE_Q;
620 } else {
621 PDAPerDisk = 2;
622 state = 3;
623 /* four of them, fone, then ftwo */
624 RF_MallocAndAdd(*pqpdap, 4 * sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t *), allocList);
625 pda_p = *pqpdap;
626 CONS_PDA(parityInfo, fone_start, fone->numSector);
627 pda_p->type = RF_PDA_TYPE_PARITY;
628 pda_p++;
629 CONS_PDA(qInfo, fone_start, fone->numSector);
630 pda_p->type = RF_PDA_TYPE_Q;
631 pda_p++;
632 CONS_PDA(parityInfo, ftwo_start, ftwo->numSector);
633 pda_p->type = RF_PDA_TYPE_PARITY;
634 pda_p++;
635 CONS_PDA(qInfo, ftwo_start, ftwo->numSector);
636 pda_p->type = RF_PDA_TYPE_Q;
637 }
638 }
639 /* figure out number of nonaccessed pda */
640 napdas = PDAPerDisk * (numDataCol - 2);
641 *nPQNodep = PDAPerDisk;
642
643 *nNodep = napdas;
644 if (napdas == 0)
645 return; /* short circuit */
646
647 /* allocate up our list of pda's */
648
649 RF_MallocAndAdd(pda_p, napdas * sizeof(RF_PhysDiskAddr_t),
650 (RF_PhysDiskAddr_t *), allocList);
651 *pdap = pda_p;
652
653 /* linkem together */
654 for (i = 0; i < (napdas - 1); i++)
655 pda_p[i].next = pda_p + (i + 1);
656
657 sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, asmap->raidAddress);
658 for (i = 0; i < numDataCol; i++) {
659 if ((pda_p - (*pdap)) == napdas)
660 continue;
661 pda_p->type = RF_PDA_TYPE_DATA;
662 pda_p->raidAddress = sosAddr + (i * secPerSU);
663 (raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
664 /* skip over dead disks */
665 if (RF_DEAD_DISK(raidPtr->Disks[pda_p->col].status))
666 continue;
667 switch (state) {
668 case 1: /* fone */
669 pda_p->numSector = fone->numSector;
670 pda_p->raidAddress += fone_start;
671 pda_p->startSector += fone_start;
672 RF_MallocAndAdd(pda_p->bufPtr, rf_RaidAddressToByte(raidPtr, pda_p->numSector), (char *), allocList);
673 break;
674 case 2: /* full stripe */
675 pda_p->numSector = secPerSU;
676 RF_MallocAndAdd(pda_p->bufPtr, rf_RaidAddressToByte(raidPtr, secPerSU), (char *), allocList);
677 break;
678 case 3: /* two slabs */
679 pda_p->numSector = fone->numSector;
680 pda_p->raidAddress += fone_start;
681 pda_p->startSector += fone_start;
682 RF_MallocAndAdd(pda_p->bufPtr, rf_RaidAddressToByte(raidPtr, pda_p->numSector), (char *), allocList);
683 pda_p++;
684 pda_p->type = RF_PDA_TYPE_DATA;
685 pda_p->raidAddress = sosAddr + (i * secPerSU);
686 (raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
687 pda_p->numSector = ftwo->numSector;
688 pda_p->raidAddress += ftwo_start;
689 pda_p->startSector += ftwo_start;
690 RF_MallocAndAdd(pda_p->bufPtr, rf_RaidAddressToByte(raidPtr, pda_p->numSector), (char *), allocList);
691 break;
692 default:
693 RF_PANIC();
694 }
695 pda_p++;
696 }
697
698 RF_ASSERT(pda_p - *pdap == napdas);
699 return;
700}
701#define DISK_NODE_PDA(node) ((node)->params[0].p)
702
703#define DISK_NODE_PARAMS(_node_,_p_) \
704 (_node_).params[0].p = _p_ ; \
705 (_node_).params[1].p = (_p_)->bufPtr; \
706 (_node_).params[2].v = parityStripeID; \
707 (_node_).params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru)
708
709void
710rf_DoubleDegSmallWrite(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
711 RF_DagHeader_t *dag_h, void *bp,
712 RF_RaidAccessFlags_t flags,
713 RF_AllocListElem_t *allocList,
714 const char *redundantReadNodeName,
715 const char *redundantWriteNodeName,
716 const char *recoveryNodeName,
717 int (*recovFunc) (RF_DagNode_t *))
718{
719 RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
720 RF_DagNode_t *nodes, *wudNodes, *rrdNodes, *recoveryNode, *blockNode,
721 *unblockNode, *rpNodes, *rqNodes, *wpNodes, *wqNodes, *termNode;
722 RF_PhysDiskAddr_t *pda, *pqPDAs;
723 RF_PhysDiskAddr_t *npdas;
724 int nWriteNodes, nNodes, nReadNodes, nRrdNodes, nWudNodes, i;
725 RF_ReconUnitNum_t which_ru;
726 int nPQNodes;
727 RF_StripeNum_t parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr, asmap->raidAddress, &which_ru);
728
729 /* simple small write case - First part looks like a reconstruct-read
730 * of the failed data units. Then a write of all data units not
731 * failed. */
732
733
734 /* Hdr | ------Block- / / \ Rrd Rrd ... Rrd Rp Rq \ \
735 * / -------PQ----- / \ \ Wud Wp WQ \ | /
736 * --Unblock- | T
737 *
738 * Rrd = read recovery data (potentially none) Wud = write user data
739 * (not incl. failed disks) Wp = Write P (could be two) Wq = Write Q
740 * (could be two)
741 *
742 */
743
744 rf_WriteGenerateFailedAccessASMs(raidPtr, asmap, &npdas, &nRrdNodes, &pqPDAs, &nPQNodes, allocList);
745
746 RF_ASSERT(asmap->numDataFailed == 1);
747
748 nWudNodes = asmap->numStripeUnitsAccessed - (asmap->numDataFailed);
749 nReadNodes = nRrdNodes + 2 * nPQNodes;
750 nWriteNodes = nWudNodes + 2 * nPQNodes;
751 nNodes = 4 + nReadNodes + nWriteNodes;
752
753 RF_MallocAndAdd(nodes, nNodes * sizeof(RF_DagNode_t), (RF_DagNode_t *), allocList);
754 blockNode = nodes;
755 unblockNode = blockNode + 1;
756 termNode = unblockNode + 1;
757 recoveryNode = termNode + 1;
758 rrdNodes = recoveryNode + 1;
759 rpNodes = rrdNodes + nRrdNodes;
760 rqNodes = rpNodes + nPQNodes;
761 wudNodes = rqNodes + nPQNodes;
762 wpNodes = wudNodes + nWudNodes;
763 wqNodes = wpNodes + nPQNodes;
764
765 dag_h->creator = "PQ_DDSimpleSmallWrite";
766 dag_h->numSuccedents = 1;
767 dag_h->succedents[0] = blockNode;
768 rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc, NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
769 termNode->antecedents[0] = unblockNode;
770 termNode->antType[0] = rf_control;
771
772 /* init the block and unblock nodes */
773 /* The block node has all the read nodes as successors */
774 rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, nReadNodes, 0, 0, 0, dag_h, "Nil", allocList);
775 for (i = 0; i < nReadNodes; i++)
776 blockNode->succedents[i] = rrdNodes + i;
777
778 /* The unblock node has all the writes as successors */
779 rf_InitNode(unblockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, 1, nWriteNodes, 0, 0, dag_h, "Nil", allocList);
780 for (i = 0; i < nWriteNodes; i++) {
781 unblockNode->antecedents[i] = wudNodes + i;
782 unblockNode->antType[i] = rf_control;
783 }
784 unblockNode->succedents[0] = termNode;
785
786#define INIT_READ_NODE(node,name) \
787 rf_InitNode(node, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, name, allocList); \
788 (node)->succedents[0] = recoveryNode; \
789 (node)->antecedents[0] = blockNode; \
790 (node)->antType[0] = rf_control;
791
792 /* build the read nodes */
793 pda = npdas;
794 for (i = 0; i < nRrdNodes; i++, pda = pda->next) {
795 INIT_READ_NODE(rrdNodes + i, "rrd");
796 DISK_NODE_PARAMS(rrdNodes[i], pda);
797 }
798
799 /* read redundancy pdas */
800 pda = pqPDAs;
801 INIT_READ_NODE(rpNodes, "Rp");
802 RF_ASSERT(pda);
803 DISK_NODE_PARAMS(rpNodes[0], pda);
804 pda++;
805 INIT_READ_NODE(rqNodes, redundantReadNodeName);
806 RF_ASSERT(pda);
807 DISK_NODE_PARAMS(rqNodes[0], pda);
808 if (nPQNodes == 2) {
809 pda++;
810 INIT_READ_NODE(rpNodes + 1, "Rp");
811 RF_ASSERT(pda);
812 DISK_NODE_PARAMS(rpNodes[1], pda);
813 pda++;
814 INIT_READ_NODE(rqNodes + 1, redundantReadNodeName);
815 RF_ASSERT(pda);
816 DISK_NODE_PARAMS(rqNodes[1], pda);
817 }
818 /* the recovery node has all reads as precedessors and all writes as
819 * successors. It generates a result for every write P or write Q
820 * node. As parameters, it takes a pda per read and a pda per stripe
821 * of user data written. It also takes as the last params the raidPtr
822 * and asm. For results, it takes PDA for P & Q. */
823
824
825 rf_InitNode(recoveryNode, rf_wait, RF_FALSE, recovFunc, rf_NullNodeUndoFunc, NULL,
826 nWriteNodes, /* succesors */
827 nReadNodes, /* preds */
828 nReadNodes + nWudNodes + 3, /* params */
829 2 * nPQNodes, /* results */
830 dag_h, recoveryNodeName, allocList);
831
832
833
834 for (i = 0; i < nReadNodes; i++) {
835 recoveryNode->antecedents[i] = rrdNodes + i;
836 recoveryNode->antType[i] = rf_control;
837 recoveryNode->params[i].p = DISK_NODE_PDA(rrdNodes + i);
838 }
839 for (i = 0; i < nWudNodes; i++) {
840 recoveryNode->succedents[i] = wudNodes + i;
841 }
842 recoveryNode->params[nReadNodes + nWudNodes].p = asmap->failedPDAs[0];
843 recoveryNode->params[nReadNodes + nWudNodes + 1].p = raidPtr;
844 recoveryNode->params[nReadNodes + nWudNodes + 2].p = asmap;
845
846 for (; i < nWriteNodes; i++)
847 recoveryNode->succedents[i] = wudNodes + i;
848
849 pda = pqPDAs;
850 recoveryNode->results[0] = pda;
851 pda++;
852 recoveryNode->results[1] = pda;
853 if (nPQNodes == 2) {
854 pda++;
855 recoveryNode->results[2] = pda;
856 pda++;
857 recoveryNode->results[3] = pda;
858 }
859 /* fill writes */
860#define INIT_WRITE_NODE(node,name) \
861 rf_InitNode(node, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, name, allocList); \
862 (node)->succedents[0] = unblockNode; \
863 (node)->antecedents[0] = recoveryNode; \
864 (node)->antType[0] = rf_control;
865
866 pda = asmap->physInfo;
867 for (i = 0; i < nWudNodes; i++) {
868 INIT_WRITE_NODE(wudNodes + i, "Wd");
869 DISK_NODE_PARAMS(wudNodes[i], pda);
870 recoveryNode->params[nReadNodes + i].p = DISK_NODE_PDA(wudNodes + i);
871 pda = pda->next;
872 }
873 /* write redundancy pdas */
874 pda = pqPDAs;
875 INIT_WRITE_NODE(wpNodes, "Wp");
876 RF_ASSERT(pda);
877 DISK_NODE_PARAMS(wpNodes[0], pda);
878 pda++;
879 INIT_WRITE_NODE(wqNodes, "Wq");
880 RF_ASSERT(pda);
881 DISK_NODE_PARAMS(wqNodes[0], pda);
882 if (nPQNodes == 2) {
883 pda++;
884 INIT_WRITE_NODE(wpNodes + 1, "Wp");
885 RF_ASSERT(pda);
886 DISK_NODE_PARAMS(wpNodes[1], pda);
887 pda++;
888 INIT_WRITE_NODE(wqNodes + 1, "Wq");
889 RF_ASSERT(pda);
890 DISK_NODE_PARAMS(wqNodes[1], pda);
891 }
892}
893#endif /* (RF_INCLUDE_PQ > 0) || (RF_INCLUDE_EVENODD > 0) */
894