1 /*	$NetBSD: rf_paritylogDiskMgr.c,v 1.13 2001/11/13 07:11:15 lukem Exp $	*/
2 /*
3  * Copyright (c) 1995 Carnegie-Mellon University.
4  * All rights reserved.
5  *
6  * Author: 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 /* Code for flushing and reintegration operations related to parity logging.
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: rf_paritylogDiskMgr.c,v 1.13 2001/11/13 07:11:15 lukem Exp $");
34 
35 #include "rf_archs.h"
36 
37 #if RF_INCLUDE_PARITYLOGGING > 0
38 
39 #include <dev/raidframe/raidframevar.h>
40 
41 #include "rf_threadstuff.h"
42 #include "rf_mcpair.h"
43 #include "rf_raid.h"
44 #include "rf_dag.h"
45 #include "rf_dagfuncs.h"
46 #include "rf_desc.h"
47 #include "rf_layout.h"
48 #include "rf_diskqueue.h"
49 #include "rf_paritylog.h"
50 #include "rf_general.h"
51 #include "rf_etimer.h"
52 #include "rf_paritylogging.h"
53 #include "rf_engine.h"
54 #include "rf_dagutils.h"
55 #include "rf_map.h"
56 #include "rf_parityscan.h"
57 
58 #include "rf_paritylogDiskMgr.h"
59 
60 static caddr_t AcquireReintBuffer(RF_RegionBufferQueue_t *);
61 
62 static caddr_t
63 AcquireReintBuffer(pool)
64 	RF_RegionBufferQueue_t *pool;
65 {
66 	caddr_t bufPtr = NULL;
67 
68 	/* Return a region buffer from the free list (pool). If the free list
69 	 * is empty, WAIT. BLOCKING */
70 
71 	RF_LOCK_MUTEX(pool->mutex);
72 	if (pool->availableBuffers > 0) {
73 		bufPtr = pool->buffers[pool->availBuffersIndex];
74 		pool->availableBuffers--;
75 		pool->availBuffersIndex++;
76 		if (pool->availBuffersIndex == pool->totalBuffers)
77 			pool->availBuffersIndex = 0;
78 		RF_UNLOCK_MUTEX(pool->mutex);
79 	} else {
80 		RF_PANIC();	/* should never happen in correct config,
81 				 * single reint */
82 		RF_WAIT_COND(pool->cond, pool->mutex);
83 	}
84 	return (bufPtr);
85 }
86 
87 static void
88 ReleaseReintBuffer(
89     RF_RegionBufferQueue_t * pool,
90     caddr_t bufPtr)
91 {
92 	/* Insert a region buffer (bufPtr) into the free list (pool).
93 	 * NON-BLOCKING */
94 
95 	RF_LOCK_MUTEX(pool->mutex);
96 	pool->availableBuffers++;
97 	pool->buffers[pool->emptyBuffersIndex] = bufPtr;
98 	pool->emptyBuffersIndex++;
99 	if (pool->emptyBuffersIndex == pool->totalBuffers)
100 		pool->emptyBuffersIndex = 0;
101 	RF_ASSERT(pool->availableBuffers <= pool->totalBuffers);
102 	RF_UNLOCK_MUTEX(pool->mutex);
103 	RF_SIGNAL_COND(pool->cond);
104 }
105 
106 
107 
108 static void
109 ReadRegionLog(
110     RF_RegionId_t regionID,
111     RF_MCPair_t * rrd_mcpair,
112     caddr_t regionBuffer,
113     RF_Raid_t * raidPtr,
114     RF_DagHeader_t ** rrd_dag_h,
115     RF_AllocListElem_t ** rrd_alloclist,
116     RF_PhysDiskAddr_t ** rrd_pda)
117 {
118 	/* Initiate the read a region log from disk.  Once initiated, return
119 	 * to the calling routine.
120 	 *
121 	 * NON-BLOCKING */
122 
123 	RF_AccTraceEntry_t *tracerec;
124 	RF_DagNode_t *rrd_rdNode;
125 
126 	/* create DAG to read region log from disk */
127 	rf_MakeAllocList(*rrd_alloclist);
128 	*rrd_dag_h = rf_MakeSimpleDAG(raidPtr, 1, 0, regionBuffer,
129 				      rf_DiskReadFunc, rf_DiskReadUndoFunc,
130 				      "Rrl", *rrd_alloclist,
131 				      RF_DAG_FLAGS_NONE,
132 				      RF_IO_NORMAL_PRIORITY);
133 
134 	/* create and initialize PDA for the core log */
135 	/* RF_Malloc(*rrd_pda, sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t
136 	 * *)); */
137 	*rrd_pda = rf_AllocPDAList(1);
138 	rf_MapLogParityLogging(raidPtr, regionID, 0, &((*rrd_pda)->row),
139 			       &((*rrd_pda)->col), &((*rrd_pda)->startSector));
140 	(*rrd_pda)->numSector = raidPtr->regionInfo[regionID].capacity;
141 
142 	if ((*rrd_pda)->next) {
143 		(*rrd_pda)->next = NULL;
144 		printf("set rrd_pda->next to NULL\n");
145 	}
146 	/* initialize DAG parameters */
147 	RF_Malloc(tracerec,sizeof(RF_AccTraceEntry_t), (RF_AccTraceEntry_t *));
148 	memset((char *) tracerec, 0, sizeof(RF_AccTraceEntry_t));
149 	(*rrd_dag_h)->tracerec = tracerec;
150 	rrd_rdNode = (*rrd_dag_h)->succedents[0]->succedents[0];
151 	rrd_rdNode->params[0].p = *rrd_pda;
152 /*  rrd_rdNode->params[1] = regionBuffer; */
153 	rrd_rdNode->params[2].v = 0;
154 	rrd_rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
155 						   0, 0, 0);
156 
157 	/* launch region log read dag */
158 	rf_DispatchDAG(*rrd_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
159 	    (void *) rrd_mcpair);
160 }
161 
162 
163 
164 static void
165 WriteCoreLog(
166     RF_ParityLog_t * log,
167     RF_MCPair_t * fwr_mcpair,
168     RF_Raid_t * raidPtr,
169     RF_DagHeader_t ** fwr_dag_h,
170     RF_AllocListElem_t ** fwr_alloclist,
171     RF_PhysDiskAddr_t ** fwr_pda)
172 {
173 	RF_RegionId_t regionID = log->regionID;
174 	RF_AccTraceEntry_t *tracerec;
175 	RF_SectorNum_t regionOffset;
176 	RF_DagNode_t *fwr_wrNode;
177 
178 	/* Initiate the write of a core log to a region log disk. Once
179 	 * initiated, return to the calling routine.
180 	 *
181 	 * NON-BLOCKING */
182 
183 	/* create DAG to write a core log to a region log disk */
184 	rf_MakeAllocList(*fwr_alloclist);
185 	*fwr_dag_h = rf_MakeSimpleDAG(raidPtr, 1, 0, log->bufPtr,
186 				      rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
187 	    "Wcl", *fwr_alloclist, RF_DAG_FLAGS_NONE, RF_IO_NORMAL_PRIORITY);
188 
189 	/* create and initialize PDA for the region log */
190 	/* RF_Malloc(*fwr_pda, sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t
191 	 * *)); */
192 	*fwr_pda = rf_AllocPDAList(1);
193 	regionOffset = log->diskOffset;
194 	rf_MapLogParityLogging(raidPtr, regionID, regionOffset,
195 			       &((*fwr_pda)->row), &((*fwr_pda)->col),
196 			       &((*fwr_pda)->startSector));
197 	(*fwr_pda)->numSector = raidPtr->numSectorsPerLog;
198 
199 	/* initialize DAG parameters */
200 	RF_Malloc(tracerec,sizeof(RF_AccTraceEntry_t), (RF_AccTraceEntry_t *));
201 	memset((char *) tracerec, 0, sizeof(RF_AccTraceEntry_t));
202 	(*fwr_dag_h)->tracerec = tracerec;
203 	fwr_wrNode = (*fwr_dag_h)->succedents[0]->succedents[0];
204 	fwr_wrNode->params[0].p = *fwr_pda;
205 /*  fwr_wrNode->params[1] = log->bufPtr; */
206 	fwr_wrNode->params[2].v = 0;
207 	fwr_wrNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
208 						   0, 0, 0);
209 
210 	/* launch the dag to write the core log to disk */
211 	rf_DispatchDAG(*fwr_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
212 	    (void *) fwr_mcpair);
213 }
214 
215 
216 static void
217 ReadRegionParity(
218     RF_RegionId_t regionID,
219     RF_MCPair_t * prd_mcpair,
220     caddr_t parityBuffer,
221     RF_Raid_t * raidPtr,
222     RF_DagHeader_t ** prd_dag_h,
223     RF_AllocListElem_t ** prd_alloclist,
224     RF_PhysDiskAddr_t ** prd_pda)
225 {
226 	/* Initiate the read region parity from disk. Once initiated, return
227 	 * to the calling routine.
228 	 *
229 	 * NON-BLOCKING */
230 
231 	RF_AccTraceEntry_t *tracerec;
232 	RF_DagNode_t *prd_rdNode;
233 
234 	/* create DAG to read region parity from disk */
235 	rf_MakeAllocList(*prd_alloclist);
236 	*prd_dag_h = rf_MakeSimpleDAG(raidPtr, 1, 0, NULL, rf_DiskReadFunc,
237 				      rf_DiskReadUndoFunc, "Rrp",
238 				      *prd_alloclist, RF_DAG_FLAGS_NONE,
239 				      RF_IO_NORMAL_PRIORITY);
240 
241 	/* create and initialize PDA for region parity */
242 	/* RF_Malloc(*prd_pda, sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t
243 	 * *)); */
244 	*prd_pda = rf_AllocPDAList(1);
245 	rf_MapRegionParity(raidPtr, regionID, &((*prd_pda)->row),
246 			   &((*prd_pda)->col), &((*prd_pda)->startSector),
247 			   &((*prd_pda)->numSector));
248 	if (rf_parityLogDebug)
249 		printf("[reading %d sectors of parity from region %d]\n",
250 		    (int) (*prd_pda)->numSector, regionID);
251 	if ((*prd_pda)->next) {
252 		(*prd_pda)->next = NULL;
253 		printf("set prd_pda->next to NULL\n");
254 	}
255 	/* initialize DAG parameters */
256 	RF_Malloc(tracerec,sizeof(RF_AccTraceEntry_t), (RF_AccTraceEntry_t *));
257 	memset((char *) tracerec, 0, sizeof(RF_AccTraceEntry_t));
258 	(*prd_dag_h)->tracerec = tracerec;
259 	prd_rdNode = (*prd_dag_h)->succedents[0]->succedents[0];
260 	prd_rdNode->params[0].p = *prd_pda;
261 	prd_rdNode->params[1].p = parityBuffer;
262 	prd_rdNode->params[2].v = 0;
263 	prd_rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
264 						   0, 0, 0);
265 	if (rf_validateDAGDebug)
266 		rf_ValidateDAG(*prd_dag_h);
267 	/* launch region parity read dag */
268 	rf_DispatchDAG(*prd_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
269 	    (void *) prd_mcpair);
270 }
271 
272 static void
273 WriteRegionParity(
274     RF_RegionId_t regionID,
275     RF_MCPair_t * pwr_mcpair,
276     caddr_t parityBuffer,
277     RF_Raid_t * raidPtr,
278     RF_DagHeader_t ** pwr_dag_h,
279     RF_AllocListElem_t ** pwr_alloclist,
280     RF_PhysDiskAddr_t ** pwr_pda)
281 {
282 	/* Initiate the write of region parity to disk. Once initiated, return
283 	 * to the calling routine.
284 	 *
285 	 * NON-BLOCKING */
286 
287 	RF_AccTraceEntry_t *tracerec;
288 	RF_DagNode_t *pwr_wrNode;
289 
290 	/* create DAG to write region log from disk */
291 	rf_MakeAllocList(*pwr_alloclist);
292 	*pwr_dag_h = rf_MakeSimpleDAG(raidPtr, 1, 0, parityBuffer,
293 				      rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
294 				      "Wrp", *pwr_alloclist,
295 				      RF_DAG_FLAGS_NONE,
296 				      RF_IO_NORMAL_PRIORITY);
297 
298 	/* create and initialize PDA for region parity */
299 	/* RF_Malloc(*pwr_pda, sizeof(RF_PhysDiskAddr_t), (RF_PhysDiskAddr_t
300 	 * *)); */
301 	*pwr_pda = rf_AllocPDAList(1);
302 	rf_MapRegionParity(raidPtr, regionID, &((*pwr_pda)->row),
303 			   &((*pwr_pda)->col), &((*pwr_pda)->startSector),
304 			   &((*pwr_pda)->numSector));
305 
306 	/* initialize DAG parameters */
307 	RF_Malloc(tracerec,sizeof(RF_AccTraceEntry_t), (RF_AccTraceEntry_t *));
308 	memset((char *) tracerec, 0, sizeof(RF_AccTraceEntry_t));
309 	(*pwr_dag_h)->tracerec = tracerec;
310 	pwr_wrNode = (*pwr_dag_h)->succedents[0]->succedents[0];
311 	pwr_wrNode->params[0].p = *pwr_pda;
312 /*  pwr_wrNode->params[1] = parityBuffer; */
313 	pwr_wrNode->params[2].v = 0;
314 	pwr_wrNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
315 						   0, 0, 0);
316 
317 	/* launch the dag to write region parity to disk */
318 	rf_DispatchDAG(*pwr_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
319 	    (void *) pwr_mcpair);
320 }
321 
322 static void
323 FlushLogsToDisk(
324     RF_Raid_t * raidPtr,
325     RF_ParityLog_t * logList)
326 {
327 	/* Flush a linked list of core logs to the log disk. Logs contain the
328 	 * disk location where they should be written.  Logs were written in
329 	 * FIFO order and that order must be preserved.
330 	 *
331 	 * Recommended optimizations: 1) allow multiple flushes to occur
332 	 * simultaneously 2) coalesce contiguous flush operations
333 	 *
334 	 * BLOCKING */
335 
336 	RF_ParityLog_t *log;
337 	RF_RegionId_t regionID;
338 	RF_MCPair_t *fwr_mcpair;
339 	RF_DagHeader_t *fwr_dag_h;
340 	RF_AllocListElem_t *fwr_alloclist;
341 	RF_PhysDiskAddr_t *fwr_pda;
342 
343 	fwr_mcpair = rf_AllocMCPair();
344 	RF_LOCK_MUTEX(fwr_mcpair->mutex);
345 
346 	RF_ASSERT(logList);
347 	log = logList;
348 	while (log) {
349 		regionID = log->regionID;
350 
351 		/* create and launch a DAG to write the core log */
352 		if (rf_parityLogDebug)
353 			printf("[initiating write of core log for region %d]\n", regionID);
354 		fwr_mcpair->flag = RF_FALSE;
355 		WriteCoreLog(log, fwr_mcpair, raidPtr, &fwr_dag_h,
356 			     &fwr_alloclist, &fwr_pda);
357 
358 		/* wait for the DAG to complete */
359 		while (!fwr_mcpair->flag)
360 			RF_WAIT_COND(fwr_mcpair->cond, fwr_mcpair->mutex);
361 		if (fwr_dag_h->status != rf_enable) {
362 			RF_ERRORMSG1("Unable to write core log to disk (region %d)\n", regionID);
363 			RF_ASSERT(0);
364 		}
365 		/* RF_Free(fwr_pda, sizeof(RF_PhysDiskAddr_t)); */
366 		rf_FreePhysDiskAddr(fwr_pda);
367 		rf_FreeDAG(fwr_dag_h);
368 		rf_FreeAllocList(fwr_alloclist);
369 
370 		log = log->next;
371 	}
372 	RF_UNLOCK_MUTEX(fwr_mcpair->mutex);
373 	rf_FreeMCPair(fwr_mcpair);
374 	rf_ReleaseParityLogs(raidPtr, logList);
375 }
376 
377 static void
378 ReintegrateRegion(
379     RF_Raid_t * raidPtr,
380     RF_RegionId_t regionID,
381     RF_ParityLog_t * coreLog)
382 {
383 	RF_MCPair_t *rrd_mcpair = NULL, *prd_mcpair, *pwr_mcpair;
384 	RF_DagHeader_t *rrd_dag_h, *prd_dag_h, *pwr_dag_h;
385 	RF_AllocListElem_t *rrd_alloclist, *prd_alloclist, *pwr_alloclist;
386 	RF_PhysDiskAddr_t *rrd_pda, *prd_pda, *pwr_pda;
387 	caddr_t parityBuffer, regionBuffer = NULL;
388 
389 	/* Reintegrate a region (regionID).
390 	 *
391 	 * 1. acquire region and parity buffers
392 	 * 2. read log from disk
393 	 * 3. read parity from disk
394 	 * 4. apply log to parity
395 	 * 5. apply core log to parity
396 	 * 6. write new parity to disk
397 	 *
398 	 * BLOCKING */
399 
400 	if (rf_parityLogDebug)
401 		printf("[reintegrating region %d]\n", regionID);
402 
403 	/* initiate read of region parity */
404 	if (rf_parityLogDebug)
405 		printf("[initiating read of parity for region %d]\n",regionID);
406 	parityBuffer = AcquireReintBuffer(&raidPtr->parityBufferPool);
407 	prd_mcpair = rf_AllocMCPair();
408 	RF_LOCK_MUTEX(prd_mcpair->mutex);
409 	prd_mcpair->flag = RF_FALSE;
410 	ReadRegionParity(regionID, prd_mcpair, parityBuffer, raidPtr,
411 			 &prd_dag_h, &prd_alloclist, &prd_pda);
412 
413 	/* if region log nonempty, initiate read */
414 	if (raidPtr->regionInfo[regionID].diskCount > 0) {
415 		if (rf_parityLogDebug)
416 			printf("[initiating read of disk log for region %d]\n",
417 			       regionID);
418 		regionBuffer = AcquireReintBuffer(&raidPtr->regionBufferPool);
419 		rrd_mcpair = rf_AllocMCPair();
420 		RF_LOCK_MUTEX(rrd_mcpair->mutex);
421 		rrd_mcpair->flag = RF_FALSE;
422 		ReadRegionLog(regionID, rrd_mcpair, regionBuffer, raidPtr,
423 			      &rrd_dag_h, &rrd_alloclist, &rrd_pda);
424 	}
425 	/* wait on read of region parity to complete */
426 	while (!prd_mcpair->flag) {
427 		RF_WAIT_COND(prd_mcpair->cond, prd_mcpair->mutex);
428 	}
429 	RF_UNLOCK_MUTEX(prd_mcpair->mutex);
430 	if (prd_dag_h->status != rf_enable) {
431 		RF_ERRORMSG("Unable to read parity from disk\n");
432 		/* add code to fail the parity disk */
433 		RF_ASSERT(0);
434 	}
435 	/* apply core log to parity */
436 	/* if (coreLog) ApplyLogsToParity(coreLog, parityBuffer); */
437 
438 	if (raidPtr->regionInfo[regionID].diskCount > 0) {
439 		/* wait on read of region log to complete */
440 		while (!rrd_mcpair->flag)
441 			RF_WAIT_COND(rrd_mcpair->cond, rrd_mcpair->mutex);
442 		RF_UNLOCK_MUTEX(rrd_mcpair->mutex);
443 		if (rrd_dag_h->status != rf_enable) {
444 			RF_ERRORMSG("Unable to read region log from disk\n");
445 			/* add code to fail the log disk */
446 			RF_ASSERT(0);
447 		}
448 		/* apply region log to parity */
449 		/* ApplyRegionToParity(regionID, regionBuffer, parityBuffer); */
450 		/* release resources associated with region log */
451 		/* RF_Free(rrd_pda, sizeof(RF_PhysDiskAddr_t)); */
452 		rf_FreePhysDiskAddr(rrd_pda);
453 		rf_FreeDAG(rrd_dag_h);
454 		rf_FreeAllocList(rrd_alloclist);
455 		rf_FreeMCPair(rrd_mcpair);
456 		ReleaseReintBuffer(&raidPtr->regionBufferPool, regionBuffer);
457 	}
458 	/* write reintegrated parity to disk */
459 	if (rf_parityLogDebug)
460 		printf("[initiating write of parity for region %d]\n",
461 		       regionID);
462 	pwr_mcpair = rf_AllocMCPair();
463 	RF_LOCK_MUTEX(pwr_mcpair->mutex);
464 	pwr_mcpair->flag = RF_FALSE;
465 	WriteRegionParity(regionID, pwr_mcpair, parityBuffer, raidPtr,
466 			  &pwr_dag_h, &pwr_alloclist, &pwr_pda);
467 	while (!pwr_mcpair->flag)
468 		RF_WAIT_COND(pwr_mcpair->cond, pwr_mcpair->mutex);
469 	RF_UNLOCK_MUTEX(pwr_mcpair->mutex);
470 	if (pwr_dag_h->status != rf_enable) {
471 		RF_ERRORMSG("Unable to write parity to disk\n");
472 		/* add code to fail the parity disk */
473 		RF_ASSERT(0);
474 	}
475 	/* release resources associated with read of old parity */
476 	/* RF_Free(prd_pda, sizeof(RF_PhysDiskAddr_t)); */
477 	rf_FreePhysDiskAddr(prd_pda);
478 	rf_FreeDAG(prd_dag_h);
479 	rf_FreeAllocList(prd_alloclist);
480 	rf_FreeMCPair(prd_mcpair);
481 
482 	/* release resources associated with write of new parity */
483 	ReleaseReintBuffer(&raidPtr->parityBufferPool, parityBuffer);
484 	/* RF_Free(pwr_pda, sizeof(RF_PhysDiskAddr_t)); */
485 	rf_FreePhysDiskAddr(pwr_pda);
486 	rf_FreeDAG(pwr_dag_h);
487 	rf_FreeAllocList(pwr_alloclist);
488 	rf_FreeMCPair(pwr_mcpair);
489 
490 	if (rf_parityLogDebug)
491 		printf("[finished reintegrating region %d]\n", regionID);
492 }
493 
494 
495 
496 static void
497 ReintegrateLogs(
498     RF_Raid_t * raidPtr,
499     RF_ParityLog_t * logList)
500 {
501 	RF_ParityLog_t *log, *freeLogList = NULL;
502 	RF_ParityLogData_t *logData, *logDataList;
503 	RF_RegionId_t regionID;
504 
505 	RF_ASSERT(logList);
506 	while (logList) {
507 		log = logList;
508 		logList = logList->next;
509 		log->next = NULL;
510 		regionID = log->regionID;
511 		ReintegrateRegion(raidPtr, regionID, log);
512 		log->numRecords = 0;
513 
514 		/* remove all items which are blocked on reintegration of this
515 		 * region */
516 		RF_LOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
517 		logData = rf_SearchAndDequeueParityLogData(raidPtr, regionID,
518 			   &raidPtr->parityLogDiskQueue.reintBlockHead,
519 			   &raidPtr->parityLogDiskQueue.reintBlockTail,
520 							   RF_TRUE);
521 		logDataList = logData;
522 		while (logData) {
523 			logData->next = rf_SearchAndDequeueParityLogData(
524 					 raidPtr, regionID,
525 					 &raidPtr->parityLogDiskQueue.reintBlockHead,
526 					 &raidPtr->parityLogDiskQueue.reintBlockTail,
527 					 RF_TRUE);
528 			logData = logData->next;
529 		}
530 		RF_UNLOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
531 
532 		/* process blocked log data and clear reintInProgress flag for
533 		 * this region */
534 		if (logDataList)
535 			rf_ParityLogAppend(logDataList, RF_TRUE, &log, RF_TRUE);
536 		else {
537 			/* Enable flushing for this region.  Holding both
538 			 * locks provides a synchronization barrier with
539 			 * DumpParityLogToDisk */
540 			RF_LOCK_MUTEX(raidPtr->regionInfo[regionID].mutex);
541 			RF_LOCK_MUTEX(raidPtr->regionInfo[regionID].reintMutex);
542 			RF_LOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
543 			raidPtr->regionInfo[regionID].diskCount = 0;
544 			raidPtr->regionInfo[regionID].reintInProgress = RF_FALSE;
545 			RF_UNLOCK_MUTEX(raidPtr->regionInfo[regionID].mutex);
546 			RF_UNLOCK_MUTEX(raidPtr->regionInfo[regionID].reintMutex);	/* flushing is now
547 											 * enabled */
548 			RF_UNLOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
549 		}
550 		/* if log wasn't used, attach it to the list of logs to be
551 		 * returned */
552 		if (log) {
553 			log->next = freeLogList;
554 			freeLogList = log;
555 		}
556 	}
557 	if (freeLogList)
558 		rf_ReleaseParityLogs(raidPtr, freeLogList);
559 }
560 
561 int
562 rf_ShutdownLogging(RF_Raid_t * raidPtr)
563 {
564 	/* shutdown parity logging 1) disable parity logging in all regions 2)
565 	 * reintegrate all regions */
566 
567 	RF_SectorCount_t diskCount;
568 	RF_RegionId_t regionID;
569 	RF_ParityLog_t *log;
570 
571 	if (rf_parityLogDebug)
572 		printf("[shutting down parity logging]\n");
573 	/* Since parity log maps are volatile, we must reintegrate all
574 	 * regions. */
575 	if (rf_forceParityLogReint) {
576 		for (regionID = 0; regionID < rf_numParityRegions; regionID++) {
577 			RF_LOCK_MUTEX(raidPtr->regionInfo[regionID].mutex);
578 			raidPtr->regionInfo[regionID].loggingEnabled =
579 				RF_FALSE;
580 			log = raidPtr->regionInfo[regionID].coreLog;
581 			raidPtr->regionInfo[regionID].coreLog = NULL;
582 			diskCount = raidPtr->regionInfo[regionID].diskCount;
583 			RF_UNLOCK_MUTEX(raidPtr->regionInfo[regionID].mutex);
584 			if (diskCount > 0 || log != NULL)
585 				ReintegrateRegion(raidPtr, regionID, log);
586 			if (log != NULL)
587 				rf_ReleaseParityLogs(raidPtr, log);
588 		}
589 	}
590 	if (rf_parityLogDebug) {
591 		printf("[parity logging disabled]\n");
592 		printf("[should be done!]\n");
593 	}
594 	return (0);
595 }
596 
597 int
598 rf_ParityLoggingDiskManager(RF_Raid_t * raidPtr)
599 {
600 	RF_ParityLog_t *reintQueue, *flushQueue;
601 	int     workNeeded, done = RF_FALSE;
602 	int s;
603 
604 	/* Main program for parity logging disk thread.  This routine waits
605 	 * for work to appear in either the flush or reintegration queues and
606 	 * is responsible for flushing core logs to the log disk as well as
607 	 * reintegrating parity regions.
608 	 *
609 	 * BLOCKING */
610 
611 	s = splbio();
612 
613 	RF_LOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
614 
615 	/*
616          * Inform our creator that we're running. Don't bother doing the
617          * mutex lock/unlock dance- we locked above, and we'll unlock
618          * below with nothing to do, yet.
619          */
620 	raidPtr->parityLogDiskQueue.threadState |= RF_PLOG_RUNNING;
621 	RF_SIGNAL_COND(raidPtr->parityLogDiskQueue.cond);
622 
623 	/* empty the work queues */
624 	flushQueue = raidPtr->parityLogDiskQueue.flushQueue;
625 	raidPtr->parityLogDiskQueue.flushQueue = NULL;
626 	reintQueue = raidPtr->parityLogDiskQueue.reintQueue;
627 	raidPtr->parityLogDiskQueue.reintQueue = NULL;
628 	workNeeded = (flushQueue || reintQueue);
629 
630 	while (!done) {
631 		while (workNeeded) {
632 			/* First, flush all logs in the flush queue, freeing
633 			 * buffers Second, reintegrate all regions which are
634 			 * reported as full. Third, append queued log data
635 			 * until blocked.
636 			 *
637 			 * Note: Incoming appends (ParityLogAppend) can block on
638 			 * either 1. empty buffer pool 2. region under
639 			 * reintegration To preserve a global FIFO ordering of
640 			 * appends, buffers are not released to the world
641 			 * until those appends blocked on buffers are removed
642 			 * from the append queue.  Similarly, regions which
643 			 * are reintegrated are not opened for general use
644 			 * until the append queue has been emptied. */
645 
646 			RF_UNLOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
647 
648 			/* empty flushQueue, using free'd log buffers to
649 			 * process bufTail */
650 			if (flushQueue)
651 			       FlushLogsToDisk(raidPtr, flushQueue);
652 
653 			/* empty reintQueue, flushing from reintTail as we go */
654 			if (reintQueue)
655 				ReintegrateLogs(raidPtr, reintQueue);
656 
657 			RF_LOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
658 			flushQueue = raidPtr->parityLogDiskQueue.flushQueue;
659 			raidPtr->parityLogDiskQueue.flushQueue = NULL;
660 			reintQueue = raidPtr->parityLogDiskQueue.reintQueue;
661 			raidPtr->parityLogDiskQueue.reintQueue = NULL;
662 			workNeeded = (flushQueue || reintQueue);
663 		}
664 		/* no work is needed at this point */
665 		if (raidPtr->parityLogDiskQueue.threadState & RF_PLOG_TERMINATE) {
666 			/* shutdown parity logging 1. disable parity logging
667 			 * in all regions 2. reintegrate all regions */
668 			done = RF_TRUE;	/* thread disabled, no work needed */
669 			RF_UNLOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
670 			rf_ShutdownLogging(raidPtr);
671 		}
672 		if (!done) {
673 			/* thread enabled, no work needed, so sleep */
674 			if (rf_parityLogDebug)
675 				printf("[parity logging disk manager sleeping]\n");
676 			RF_WAIT_COND(raidPtr->parityLogDiskQueue.cond,
677 				     raidPtr->parityLogDiskQueue.mutex);
678 			if (rf_parityLogDebug)
679 				printf("[parity logging disk manager just woke up]\n");
680 			flushQueue = raidPtr->parityLogDiskQueue.flushQueue;
681 			raidPtr->parityLogDiskQueue.flushQueue = NULL;
682 			reintQueue = raidPtr->parityLogDiskQueue.reintQueue;
683 			raidPtr->parityLogDiskQueue.reintQueue = NULL;
684 			workNeeded = (flushQueue || reintQueue);
685 		}
686 	}
687 	/*
688          * Announce that we're done.
689          */
690 	RF_LOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
691 	raidPtr->parityLogDiskQueue.threadState |= RF_PLOG_SHUTDOWN;
692 	RF_UNLOCK_MUTEX(raidPtr->parityLogDiskQueue.mutex);
693 	RF_SIGNAL_COND(raidPtr->parityLogDiskQueue.cond);
694 
695 	splx(s);
696 
697 	/*
698          * In the NetBSD kernel, the thread must exit; returning would
699          * cause the proc trampoline to attempt to return to userspace.
700          */
701 	kthread_exit(0);	/* does not return */
702 }
703 #endif				/* RF_INCLUDE_PARITYLOGGING > 0 */
704