PDMAsyncCompletionFileNormal.cpp@ 26671

Last change on this file since 26671 was 26671, checked in by vboxsync, 15 years ago
AsyncCompletion: Make it possible to limit the bandwidth of a VM
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1	/* $Id: PDMAsyncCompletionFileNormal.cpp 26671 2010-02-22 07:21:34Z vboxsync $ */
2	/** @file
3	* PDM Async I/O - Transport data asynchronous in R3 using EMT.
4	* Async File I/O manager.
5	*/
6
7	/*
8	* Copyright (C) 2006-2008 Sun Microsystems, Inc.
9	*
10	* This file is part of VirtualBox Open Source Edition (OSE), as
11	* available from http://www.virtualbox.org. This file is free software;
12	* you can redistribute it and/or modify it under the terms of the GNU
13	* General Public License (GPL) as published by the Free Software
14	* Foundation, in version 2 as it comes in the "COPYING" file of the
15	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
16	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
17	*
18	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
19	* Clara, CA 95054 USA or visit http://www.sun.com if you need
20	* additional information or have any questions.
21	*/
22	#define LOG_GROUP LOG_GROUP_PDM_ASYNC_COMPLETION
23	#include <iprt/types.h>
24	#include <iprt/asm.h>
25	#include <iprt/file.h>
26	#include <iprt/mem.h>
27	#include <iprt/string.h>
28	#include <iprt/assert.h>
29	#include <VBox/log.h>
30
31	#include "PDMAsyncCompletionFileInternal.h"
32
33	/** The update period for the I/O load statistics in ms. */
34	#define PDMACEPFILEMGR_LOAD_UPDATE_PERIOD 1000
35	/** Maximum number of requests a manager will handle. */
36	#define PDMACEPFILEMGR_REQS_MAX 512 /* @todo: Find better solution wrt. the request number*/
37
38	/*******************************************************************************
39	* Internal functions *
40	*******************************************************************************/
41	static int pdmacFileAioMgrNormalProcessTaskList(PPDMACTASKFILE pTaskHead,
42	PPDMACEPFILEMGR pAioMgr,
43	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint);
44
45
46	int pdmacFileAioMgrNormalInit(PPDMACEPFILEMGR pAioMgr)
47	{
48	int rc = VINF_SUCCESS;
49
50	rc = RTFileAioCtxCreate(&pAioMgr->hAioCtx, RTFILEAIO_UNLIMITED_REQS);
51	if (rc == VERR_OUT_OF_RANGE)
52	rc = RTFileAioCtxCreate(&pAioMgr->hAioCtx, PDMACEPFILEMGR_REQS_MAX);
53
54	if (RT_SUCCESS(rc))
55	{
56	/* Initialize request handle array. */
57	pAioMgr->iFreeEntryNext = 0;
58	pAioMgr->iFreeReqNext = 0;
59	pAioMgr->cReqEntries = PDMACEPFILEMGR_REQS_MAX + 1;
60	pAioMgr->pahReqsFree = (RTFILEAIOREQ )RTMemAllocZ(pAioMgr->cReqEntries sizeof(RTFILEAIOREQ));
61
62	if (pAioMgr->pahReqsFree)
63	{
64	return VINF_SUCCESS;
65	}
66	else
67	{
68	RTFileAioCtxDestroy(pAioMgr->hAioCtx);
69	rc = VERR_NO_MEMORY;
70	}
71	}
72
73	return rc;
74	}
75
76	void pdmacFileAioMgrNormalDestroy(PPDMACEPFILEMGR pAioMgr)
77	{
78	RTFileAioCtxDestroy(pAioMgr->hAioCtx);
79
80	while (pAioMgr->iFreeReqNext != pAioMgr->iFreeEntryNext)
81	{
82	RTFileAioReqDestroy(pAioMgr->pahReqsFree[pAioMgr->iFreeReqNext]);
83	pAioMgr->iFreeReqNext = (pAioMgr->iFreeReqNext + 1) % pAioMgr->cReqEntries;
84	}
85
86	RTMemFree(pAioMgr->pahReqsFree);
87	}
88
89	/**
90	* Sorts the endpoint list with insertion sort.
91	*/
92	static void pdmacFileAioMgrNormalEndpointsSortByLoad(PPDMACEPFILEMGR pAioMgr)
93	{
94	PPDMASYNCCOMPLETIONENDPOINTFILE pEpPrev, pEpCurr, pEpNextToSort;
95
96	pEpPrev = pAioMgr->pEndpointsHead;
97	pEpCurr = pEpPrev->AioMgr.pEndpointNext;
98
99	while (pEpCurr)
100	{
101	/* Remember the next element to sort because the list might change. */
102	pEpNextToSort = pEpCurr->AioMgr.pEndpointNext;
103
104	/* Unlink the current element from the list. */
105	PPDMASYNCCOMPLETIONENDPOINTFILE pPrev = pEpCurr->AioMgr.pEndpointPrev;
106	PPDMASYNCCOMPLETIONENDPOINTFILE pNext = pEpCurr->AioMgr.pEndpointNext;
107
108	if (pPrev)
109	pPrev->AioMgr.pEndpointNext = pNext;
110	else
111	pAioMgr->pEndpointsHead = pNext;
112
113	if (pNext)
114	pNext->AioMgr.pEndpointPrev = pPrev;
115
116	/* Go back until we reached the place to insert the current endpoint into. */
117	while (pEpPrev && (pEpPrev->AioMgr.cReqsPerSec < pEpCurr->AioMgr.cReqsPerSec))
118	pEpPrev = pEpPrev->AioMgr.pEndpointPrev;
119
120	/* Link the endpoint into the list. */
121	if (pEpPrev)
122	pNext = pEpPrev->AioMgr.pEndpointNext;
123	else
124	pNext = pAioMgr->pEndpointsHead;
125
126	pEpCurr->AioMgr.pEndpointNext = pNext;
127	pEpCurr->AioMgr.pEndpointPrev = pEpPrev;
128
129	if (pNext)
130	pNext->AioMgr.pEndpointPrev = pEpCurr;
131
132	if (pEpPrev)
133	pEpPrev->AioMgr.pEndpointNext = pEpCurr;
134	else
135	pAioMgr->pEndpointsHead = pEpCurr;
136
137	pEpCurr = pEpNextToSort;
138	}
139
140	#ifdef DEBUG
141	/* Validate sorting alogrithm */
142	unsigned cEndpoints = 0;
143	pEpCurr = pAioMgr->pEndpointsHead;
144
145	AssertMsg(pEpCurr, ("No endpoint in the list?\n"));
146	AssertMsg(!pEpCurr->AioMgr.pEndpointPrev, ("First element in the list points to previous element\n"));
147
148	while (pEpCurr)
149	{
150	cEndpoints++;
151
152	PPDMASYNCCOMPLETIONENDPOINTFILE pNext = pEpCurr->AioMgr.pEndpointNext;
153	PPDMASYNCCOMPLETIONENDPOINTFILE pPrev = pEpCurr->AioMgr.pEndpointPrev;
154
155	Assert(!pNext \|\| pNext->AioMgr.cReqsPerSec <= pEpCurr->AioMgr.cReqsPerSec);
156	Assert(!pPrev \|\| pPrev->AioMgr.cReqsPerSec >= pEpCurr->AioMgr.cReqsPerSec);
157
158	pEpCurr = pNext;
159	}
160
161	AssertMsg(cEndpoints == pAioMgr->cEndpoints, ("Endpoints lost during sort!\n"));
162
163	#endif
164	}
165
166	/**
167	* Removes an endpoint from the currently assigned manager.
168	*
169	* @returns TRUE if there are still requests pending on the current manager for this endpoint.
170	* FALSE otherwise.
171	* @param pEndpointRemove The endpoint to remove.
172	*/
173	static bool pdmacFileAioMgrNormalRemoveEndpoint(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointRemove)
174	{
175	PPDMASYNCCOMPLETIONENDPOINTFILE pPrev = pEndpointRemove->AioMgr.pEndpointPrev;
176	PPDMASYNCCOMPLETIONENDPOINTFILE pNext = pEndpointRemove->AioMgr.pEndpointNext;
177	PPDMACEPFILEMGR pAioMgr = pEndpointRemove->pAioMgr;
178
179	pAioMgr->cEndpoints--;
180
181	if (pPrev)
182	pPrev->AioMgr.pEndpointNext = pNext;
183	else
184	pAioMgr->pEndpointsHead = pNext;
185
186	if (pNext)
187	pNext->AioMgr.pEndpointPrev = pPrev;
188
189	/* Make sure that there is no request pending on this manager for the endpoint. */
190	if (!pEndpointRemove->AioMgr.cRequestsActive)
191	{
192	Assert(!pEndpointRemove->pFlushReq);
193
194	/* Reopen the file so that the new endpoint can reassociate with the file */
195	RTFileClose(pEndpointRemove->File);
196	int rc = RTFileOpen(&pEndpointRemove->File, pEndpointRemove->Core.pszUri, pEndpointRemove->fFlags);
197	AssertRC(rc);
198	return false;
199	}
200
201	return true;
202	}
203
204	static bool pdmacFileAioMgrNormalIsBalancePossible(PPDMACEPFILEMGR pAioMgr)
205	{
206	/* Balancing doesn't make sense with only one endpoint. */
207	if (pAioMgr->cEndpoints == 1)
208	return false;
209
210	/* Doesn't make sens to move endpoints if only one produces the whole load */
211	unsigned cEndpointsWithLoad = 0;
212
213	PPDMASYNCCOMPLETIONENDPOINTFILE pCurr = pAioMgr->pEndpointsHead;
214
215	while (pCurr)
216	{
217	if (pCurr->AioMgr.cReqsPerSec)
218	cEndpointsWithLoad++;
219
220	pCurr = pCurr->AioMgr.pEndpointNext;
221	}
222
223	return (cEndpointsWithLoad > 1);
224	}
225
226	/**
227	* Creates a new I/O manager and spreads the I/O load of the endpoints
228	* between the given I/O manager and the new one.
229	*
230	* @returns nothing.
231	* @param pAioMgr The I/O manager with high I/O load.
232	*/
233	static void pdmacFileAioMgrNormalBalanceLoad(PPDMACEPFILEMGR pAioMgr)
234	{
235	PPDMACEPFILEMGR pAioMgrNew = NULL;
236	int rc = VINF_SUCCESS;
237
238	/*
239	* Check if balancing would improve the situation.
240	*/
241	if (pdmacFileAioMgrNormalIsBalancePossible(pAioMgr))
242	{
243	rc = pdmacFileAioMgrCreate((PPDMASYNCCOMPLETIONEPCLASSFILE)pAioMgr->pEndpointsHead->Core.pEpClass,
244	&pAioMgrNew, false);
245	if (RT_SUCCESS(rc))
246	{
247	/* We will sort the list by request count per second. */
248	pdmacFileAioMgrNormalEndpointsSortByLoad(pAioMgr);
249
250	/* Now move some endpoints to the new manager. */
251	unsigned cReqsHere = pAioMgr->pEndpointsHead->AioMgr.cReqsPerSec;
252	unsigned cReqsOther = 0;
253	PPDMASYNCCOMPLETIONENDPOINTFILE pCurr = pAioMgr->pEndpointsHead->AioMgr.pEndpointNext;
254
255	while (pCurr)
256	{
257	if (cReqsHere <= cReqsOther)
258	{
259	/*
260	* The other manager has more requests to handle now.
261	* We will keep the current endpoint.
262	*/
263	Log(("Keeping endpoint %#p{%s} with %u reqs/s\n", pCurr->Core.pszUri, pCurr->AioMgr.cReqsPerSec));
264	cReqsHere += pCurr->AioMgr.cReqsPerSec;
265	pCurr = pCurr->AioMgr.pEndpointNext;
266	}
267	else
268	{
269	/* Move to other endpoint. */
270	Log(("Moving endpoint %#p{%s} with %u reqs/s to other manager\n", pCurr, pCurr->Core.pszUri, pCurr->AioMgr.cReqsPerSec));
271	cReqsOther += pCurr->AioMgr.cReqsPerSec;
272
273	PPDMASYNCCOMPLETIONENDPOINTFILE pMove = pCurr;
274
275	pCurr = pCurr->AioMgr.pEndpointNext;
276
277	bool fReqsPending = pdmacFileAioMgrNormalRemoveEndpoint(pMove);
278
279	if (fReqsPending)
280	{
281	pMove->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_REMOVING;
282	pMove->AioMgr.fMoving = true;
283	pMove->AioMgr.pAioMgrDst = pAioMgrNew;
284	}
285	else
286	{
287	pMove->AioMgr.fMoving = false;
288	pMove->AioMgr.pAioMgrDst = NULL;
289	pdmacFileAioMgrAddEndpoint(pAioMgrNew, pMove);
290	}
291	}
292	}
293	}
294	else
295	{
296	/* Don't process further but leave a log entry about reduced performance. */
297	LogRel(("AIOMgr: Could not create new I/O manager (rc=%Rrc). Expect reduced performance\n", rc));
298	}
299	}
300	else
301	Log(("AIOMgr: Load balancing would not improve anything\n"));
302	}
303
304	/**
305	* Error handler which will create the failsafe managers and destroy the failed I/O manager.
306	*
307	* @returns VBox status code
308	* @param pAioMgr The I/O manager the error ocurred on.
309	* @param rc The error code.
310	*/
311	static int pdmacFileAioMgrNormalErrorHandler(PPDMACEPFILEMGR pAioMgr, int rc, RT_SRC_POS_DECL)
312	{
313	LogRel(("AIOMgr: I/O manager %#p encountered a critical error (rc=%Rrc) during operation. Falling back to failsafe mode. Expect reduced performance\n",
314	pAioMgr, rc));
315	LogRel(("AIOMgr: Error happened in %s:(%u){%s}\n", RT_SRC_POS_ARGS));
316	LogRel(("AIOMgr: Please contact the product vendor\n"));
317
318	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pAioMgr->pEndpointsHead->Core.pEpClass;
319
320	pAioMgr->enmState = PDMACEPFILEMGRSTATE_FAULT;
321	ASMAtomicWriteBool(&pEpClassFile->fFailsafe, true);
322
323	AssertMsgFailed(("Implement\n"));
324	return VINF_SUCCESS;
325	}
326
327	/**
328	* Put a list of tasks in the pending request list of an endpoint.
329	*/
330	DECLINLINE(void) pdmacFileAioMgrEpAddTaskList(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint, PPDMACTASKFILE pTaskHead)
331	{
332	/* Add the rest of the tasks to the pending list */
333	if (!pEndpoint->AioMgr.pReqsPendingHead)
334	{
335	Assert(!pEndpoint->AioMgr.pReqsPendingTail);
336	pEndpoint->AioMgr.pReqsPendingHead = pTaskHead;
337	}
338	else
339	{
340	Assert(pEndpoint->AioMgr.pReqsPendingTail);
341	pEndpoint->AioMgr.pReqsPendingTail->pNext = pTaskHead;
342	}
343
344	/* Update the tail. */
345	while (pTaskHead->pNext)
346	pTaskHead = pTaskHead->pNext;
347
348	pEndpoint->AioMgr.pReqsPendingTail = pTaskHead;
349	}
350
351	/**
352	* Put one task in the pending request list of an endpoint.
353	*/
354	DECLINLINE(void) pdmacFileAioMgrEpAddTask(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint, PPDMACTASKFILE pTask)
355	{
356	/* Add the rest of the tasks to the pending list */
357	if (!pEndpoint->AioMgr.pReqsPendingHead)
358	{
359	Assert(!pEndpoint->AioMgr.pReqsPendingTail);
360	pEndpoint->AioMgr.pReqsPendingHead = pTask;
361	}
362	else
363	{
364	Assert(pEndpoint->AioMgr.pReqsPendingTail);
365	pEndpoint->AioMgr.pReqsPendingTail->pNext = pTask;
366	}
367
368	pEndpoint->AioMgr.pReqsPendingTail = pTask;
369	}
370
371	/**
372	* Wrapper around RTFIleAioCtxSubmit() which is also doing error handling.
373	*/
374	static int pdmacFileAioMgrNormalReqsEnqueue(PPDMACEPFILEMGR pAioMgr,
375	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
376	PRTFILEAIOREQ pahReqs, unsigned cReqs)
377	{
378	int rc;
379
380	pAioMgr->cRequestsActive += cReqs;
381	pEndpoint->AioMgr.cRequestsActive += cReqs;
382
383	LogFlow(("Enqueuing %d requests. I/O manager has a total of %d active requests now\n", cReqs, pAioMgr->cRequestsActive));
384	LogFlow(("Endpoint has a total of %d active requests now\n", pEndpoint->AioMgr.cRequestsActive));
385
386	rc = RTFileAioCtxSubmit(pAioMgr->hAioCtx, pahReqs, cReqs);
387	if (RT_FAILURE(rc))
388	{
389	if (rc == VERR_FILE_AIO_INSUFFICIENT_RESSOURCES)
390	{
391	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClass = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->Core.pEpClass;
392
393	/*
394	* We run out of resources.
395	* Need to check which requests got queued
396	* and put the rest on the pending list again.
397	*/
398	if (RT_UNLIKELY(!pEpClass->fOutOfResourcesWarningPrinted))
399	{
400	pEpClass->fOutOfResourcesWarningPrinted = true;
401	LogRel(("AIOMgr: The operating system doesn't have enough resources "
402	"to handle the I/O load of the VM. Expect reduced I/O performance\n"));
403	}
404
405	for (size_t i = 0; i < cReqs; i++)
406	{
407	int rcReq = RTFileAioReqGetRC(pahReqs[i], NULL);
408
409	if (rcReq != VERR_FILE_AIO_IN_PROGRESS)
410	{
411	AssertMsg(rcReq == VERR_FILE_AIO_NOT_SUBMITTED,
412	("Request returned unexpected return code: rc=%Rrc\n", rcReq));
413
414	PPDMACTASKFILE pTask = (PPDMACTASKFILE)RTFileAioReqGetUser(pahReqs[i]);
415
416	/* Put the entry on the free array */
417	pAioMgr->pahReqsFree[pAioMgr->iFreeEntryNext] = pahReqs[i];
418	pAioMgr->iFreeEntryNext = (pAioMgr->iFreeEntryNext + 1) % pAioMgr->cReqEntries;
419
420	pdmacFileAioMgrEpAddTask(pEndpoint, pTask);
421	pAioMgr->cRequestsActive--;
422	pEndpoint->AioMgr.cRequestsActive--;
423	}
424	}
425	LogFlow(("Removed requests. I/O manager has a total of %d active requests now\n", pAioMgr->cRequestsActive));
426	LogFlow(("Endpoint has a total of %d active requests now\n", pEndpoint->AioMgr.cRequestsActive));
427	}
428	else
429	AssertMsgFailed(("Unexpected return code rc=%Rrc\n", rc));
430	}
431
432	return rc;
433	}
434
435	/**
436	* Allocates a async I/O request.
437	*
438	* @returns Handle to the request.
439	* @param pAioMgr The I/O manager.
440	*/
441	static RTFILEAIOREQ pdmacFileAioMgrNormalRequestAlloc(PPDMACEPFILEMGR pAioMgr)
442	{
443	RTFILEAIOREQ hReq = NIL_RTFILEAIOREQ;
444
445	/* Get a request handle. */
446	if (pAioMgr->iFreeReqNext != pAioMgr->iFreeEntryNext)
447	{
448	hReq = pAioMgr->pahReqsFree[pAioMgr->iFreeReqNext];
449	pAioMgr->pahReqsFree[pAioMgr->iFreeReqNext] = NIL_RTFILEAIOREQ;
450	pAioMgr->iFreeReqNext = (pAioMgr->iFreeReqNext + 1) % pAioMgr->cReqEntries;
451	}
452	else
453	{
454	int rc = RTFileAioReqCreate(&hReq);
455	AssertRC(rc);
456	}
457
458	return hReq;
459	}
460
461	static bool pdmacFileAioMgrNormalIsRangeLocked(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
462	RTFOFF offStart, size_t cbRange,
463	PPDMACTASKFILE pTask)
464	{
465	PPDMACFILERANGELOCK pRangeLock = NULL; /** < Range lock */
466
467	AssertMsg( pTask->enmTransferType == PDMACTASKFILETRANSFER_WRITE
468	\|\| pTask->enmTransferType == PDMACTASKFILETRANSFER_READ,
469	("Invalid task type %d\n", pTask->enmTransferType));
470
471	pRangeLock = (PPDMACFILERANGELOCK)RTAvlrFileOffsetGet(pEndpoint->AioMgr.pTreeRangesLocked, offStart);
472	if (!pRangeLock)
473	{
474	pRangeLock = (PPDMACFILERANGELOCK)RTAvlrFileOffsetGetBestFit(pEndpoint->AioMgr.pTreeRangesLocked, offStart, true);
475	/* Check if we intersect with the range. */
476	if ( !pRangeLock
477	\|\| !( (pRangeLock->Core.Key) <= (offStart + (RTFOFF)cbRange - 1)
478	&& (pRangeLock->Core.KeyLast) >= offStart))
479	{
480	pRangeLock = NULL; /* False alarm */
481	}
482	}
483
484	/* Check whether we have one of the situations explained below */
485	if ( pRangeLock
486	#if 0 /** @todo: later. For now we will just block all requests if they interfere */
487	&& ( (pRangeLock->fReadLock && pTask->enmTransferType == PDMACTASKFILETRANSFER_WRITE)
488	\|\| (!pRangeLock->fReadLock)
489	#endif
490	)
491	{
492	/* Add to the list. */
493	pTask->pNext = NULL;
494
495	if (!pRangeLock->pWaitingTasksHead)
496	{
497	Assert(!pRangeLock->pWaitingTasksTail);
498	pRangeLock->pWaitingTasksHead = pTask;
499	pRangeLock->pWaitingTasksTail = pTask;
500	}
501	else
502	{
503	AssertPtr(pRangeLock->pWaitingTasksTail);
504	pRangeLock->pWaitingTasksTail->pNext = pTask;
505	pRangeLock->pWaitingTasksTail = pTask;
506	}
507	return true;
508	}
509
510	return false;
511	}
512
513	static int pdmacFileAioMgrNormalRangeLock(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
514	RTFOFF offStart, size_t cbRange,
515	PPDMACTASKFILE pTask)
516	{
517	AssertMsg(!pdmacFileAioMgrNormalIsRangeLocked(pEndpoint, offStart, cbRange, pTask),
518	("Range is already locked offStart=%RTfoff cbRange=%u\n",
519	offStart, cbRange));
520
521	PPDMACFILERANGELOCK pRangeLock = (PPDMACFILERANGELOCK)RTMemAllocZ(sizeof(PDMACFILERANGELOCK));
522	if (!pRangeLock)
523	return VERR_NO_MEMORY;
524
525	/* Init the lock. */
526	pRangeLock->Core.Key = offStart;
527	pRangeLock->Core.KeyLast = offStart + cbRange - 1;
528	pRangeLock->cRefs = 1;
529	pRangeLock->fReadLock = pTask->enmTransferType == PDMACTASKFILETRANSFER_READ;
530
531	bool fInserted = RTAvlrFileOffsetInsert(pEndpoint->AioMgr.pTreeRangesLocked, &pRangeLock->Core);
532	AssertMsg(fInserted, ("Range lock was not inserted!\n"));
533
534	/* Let the task point to its lock. */
535	pTask->pRangeLock = pRangeLock;
536
537	return VINF_SUCCESS;
538	}
539
540	static int pdmacFileAioMgrNormalRangeLockFree(PPDMACEPFILEMGR pAioMgr,
541	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
542	PPDMACFILERANGELOCK pRangeLock)
543	{
544	PPDMACTASKFILE pTasksWaitingHead;
545
546	AssertPtr(pRangeLock);
547	Assert(pRangeLock->cRefs == 1);
548
549	RTAvlrFileOffsetRemove(pEndpoint->AioMgr.pTreeRangesLocked, pRangeLock->Core.Key);
550	pTasksWaitingHead = pRangeLock->pWaitingTasksHead;
551	RTMemFree(pRangeLock);
552
553	return pdmacFileAioMgrNormalProcessTaskList(pTasksWaitingHead, pAioMgr, pEndpoint);
554	}
555
556	static int pdmacFileAioMgrNormalTaskPrepare(PPDMACEPFILEMGR pAioMgr,
557	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
558	PPDMACTASKFILE pTask, PRTFILEAIOREQ phReq)
559	{
560	int rc = VINF_SUCCESS;
561	RTFILEAIOREQ hReq = NIL_RTFILEAIOREQ;
562	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->Core.pEpClass;
563	void *pvBuf = pTask->DataSeg.pvSeg;
564
565	/* Get a request handle. */
566	hReq = pdmacFileAioMgrNormalRequestAlloc(pAioMgr);
567	AssertMsg(hReq != NIL_RTFILEAIOREQ, ("Out of request handles\n"));
568
569	/*
570	* Check if the alignment requirements are met.
571	* Offset, transfer size and buffer address
572	* need to be on a 512 boundary.
573	*/
574	RTFOFF offStart = pTask->Off & ~(RTFOFF)(512-1);
575	size_t cbToTransfer = RT_ALIGN_Z(pTask->DataSeg.cbSeg + (pTask->Off - offStart), 512);
576	PDMACTASKFILETRANSFER enmTransferType = pTask->enmTransferType;
577
578	AssertMsg( pTask->enmTransferType == PDMACTASKFILETRANSFER_WRITE
579	\|\| (uint64_t)(offStart + cbToTransfer) <= pEndpoint->cbFile,
580	("Read exceeds file size offStart=%RTfoff cbToTransfer=%d cbFile=%llu\n",
581	offStart, cbToTransfer, pEndpoint->cbFile));
582
583	pTask->fPrefetch = false;
584
585	/*
586	* Before we start to setup the request we have to check whether there is a task
587	* already active which range intersects with ours. We have to defer execution
588	* of this task in two cases:
589	* - The pending task is a write and the current is either read or write
590	* - The pending task is a read and the current task is a write task.
591	*
592	* To check whether a range is currently "locked" we use the AVL tree where every pending task
593	* is stored by its file offset range. The current task will be added to the active task
594	* and will be executed when the active one completes. (The method below
595	* which checks whether a range is already used will add the task)
596	*
597	* This is neccessary because of the requirementto align all requests to a 512 boundary
598	* which is enforced by the host OS (Linux and Windows atm). It is possible that
599	* we have to process unaligned tasks and need to align them using bounce buffers.
600	* While the data is feteched from the file another request might arrive writing to
601	* the same range. This will result in data corruption if both are executed concurrently.
602	*/
603	bool fLocked = pdmacFileAioMgrNormalIsRangeLocked(pEndpoint, offStart, cbToTransfer, pTask);
604
605	if (!fLocked)
606	{
607	if ( RT_UNLIKELY(cbToTransfer != pTask->DataSeg.cbSeg)
608	\|\| RT_UNLIKELY(offStart != pTask->Off)
609	\|\| ((pEpClassFile->uBitmaskAlignment & (RTR3UINTPTR)pvBuf) != (RTR3UINTPTR)pvBuf))
610	{
611	LogFlow(("Using bounce buffer for task %#p cbToTransfer=%zd cbSeg=%zd offStart=%RTfoff off=%RTfoff\n",
612	pTask, cbToTransfer, pTask->DataSeg.cbSeg, offStart, pTask->Off));
613
614	/* Create bounce buffer. */
615	pTask->fBounceBuffer = true;
616
617	AssertMsg(pTask->Off >= offStart, ("Overflow in calculation Off=%llu offStart=%llu\n",
618	pTask->Off, offStart));
619	pTask->uBounceBufOffset = pTask->Off - offStart;
620
621	/** @todo: I think we need something like a RTMemAllocAligned method here.
622	* Current assumption is that the maximum alignment is 4096byte
623	* (GPT disk on Windows)
624	* so we can use RTMemPageAlloc here.
625	*/
626	pTask->pvBounceBuffer = RTMemPageAlloc(cbToTransfer);
627	if (RT_LIKELY(pTask->pvBounceBuffer))
628	{
629	pvBuf = pTask->pvBounceBuffer;
630
631	if (pTask->enmTransferType == PDMACTASKFILETRANSFER_WRITE)
632	{
633	if ( RT_UNLIKELY(cbToTransfer != pTask->DataSeg.cbSeg)
634	\|\| RT_UNLIKELY(offStart != pTask->Off))
635	{
636	/* We have to fill the buffer first before we can update the data. */
637	LogFlow(("Prefetching data for task %#p\n", pTask));
638	pTask->fPrefetch = true;
639	enmTransferType = PDMACTASKFILETRANSFER_READ;
640	}
641	else
642	memcpy(pvBuf, pTask->DataSeg.pvSeg, pTask->DataSeg.cbSeg);
643	}
644	}
645	else
646	rc = VERR_NO_MEMORY;
647	}
648	else
649	pTask->fBounceBuffer = false;
650
651	if (RT_SUCCESS(rc))
652	{
653	AssertMsg((pEpClassFile->uBitmaskAlignment & (RTR3UINTPTR)pvBuf) == (RTR3UINTPTR)pvBuf,
654	("AIO: Alignment restrictions not met! pvBuf=%p uBitmaskAlignment=%p\n", pvBuf, pEpClassFile->uBitmaskAlignment));
655
656	if (enmTransferType == PDMACTASKFILETRANSFER_WRITE)
657	{
658	/* Grow the file if needed. */
659	if (RT_UNLIKELY((uint64_t)(pTask->Off + pTask->DataSeg.cbSeg) > pEndpoint->cbFile))
660	{
661	ASMAtomicWriteU64(&pEndpoint->cbFile, pTask->Off + pTask->DataSeg.cbSeg);
662	RTFileSetSize(pEndpoint->File, pTask->Off + pTask->DataSeg.cbSeg);
663	}
664
665	rc = RTFileAioReqPrepareWrite(hReq, pEndpoint->File,
666	offStart, pvBuf, cbToTransfer, pTask);
667	}
668	else
669	rc = RTFileAioReqPrepareRead(hReq, pEndpoint->File,
670	offStart, pvBuf, cbToTransfer, pTask);
671	AssertRC(rc);
672
673	rc = pdmacFileAioMgrNormalRangeLock(pEndpoint, offStart, cbToTransfer, pTask);
674
675	if (RT_SUCCESS(rc))
676	*phReq = hReq;
677	else
678	{
679	/* Cleanup */
680	if (pTask->fBounceBuffer)
681	RTMemPageFree(pTask->pvBounceBuffer);
682	}
683	}
684	}
685	else
686	{
687	LogFlow(("Task %#p was deferred because the access range is locked\n", pTask));
688	rc = VINF_SUCCESS;
689	}
690
691	return rc;
692	}
693
694	static int pdmacFileAioMgrNormalProcessTaskList(PPDMACTASKFILE pTaskHead,
695	PPDMACEPFILEMGR pAioMgr,
696	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
697	{
698	RTFILEAIOREQ apReqs[20];
699	unsigned cRequests = 0;
700	unsigned cMaxRequests = PDMACEPFILEMGR_REQS_MAX - pAioMgr->cRequestsActive;
701	int rc = VINF_SUCCESS;
702
703	AssertMsg(pEndpoint->enmState == PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE,
704	("Trying to process request lists of a non active endpoint!\n"));
705
706	/* Go through the list and queue the requests until we get a flush request */
707	while ( pTaskHead
708	&& !pEndpoint->pFlushReq
709	&& (cMaxRequests > 0)
710	&& RT_SUCCESS(rc))
711	{
712	PPDMACTASKFILE pCurr = pTaskHead;
713
714	if (!pdmacFileBwMgrIsTransferAllowed(pEndpoint->pBwMgr, pCurr->DataSeg.cbSeg))
715	{
716	pAioMgr->fBwLimitReached = true;
717	break;
718	}
719
720	pTaskHead = pTaskHead->pNext;
721
722	pCurr->pNext = NULL;
723
724	AssertMsg(VALID_PTR(pCurr->pEndpoint) && (pCurr->pEndpoint == pEndpoint),
725	("Endpoints do not match\n"));
726
727	switch (pCurr->enmTransferType)
728	{
729	case PDMACTASKFILETRANSFER_FLUSH:
730	{
731	/* If there is no data transfer request this flush request finished immediately. */
732	if (!pEndpoint->AioMgr.cRequestsActive)
733	{
734	pCurr->pfnCompleted(pCurr, pCurr->pvUser);
735	pdmacFileTaskFree(pEndpoint, pCurr);
736	}
737	else
738	{
739	Assert(!pEndpoint->pFlushReq);
740	pEndpoint->pFlushReq = pCurr;
741	}
742	break;
743	}
744	case PDMACTASKFILETRANSFER_READ:
745	case PDMACTASKFILETRANSFER_WRITE:
746	{
747	RTFILEAIOREQ hReq = NIL_RTFILEAIOREQ;
748
749	rc = pdmacFileAioMgrNormalTaskPrepare(pAioMgr, pEndpoint, pCurr, &hReq);
750	AssertRC(rc);
751
752	if (hReq != NIL_RTFILEAIOREQ)
753	{
754	apReqs[cRequests] = hReq;
755	pEndpoint->AioMgr.cReqsProcessed++;
756	cMaxRequests--;
757	cRequests++;
758	if (cRequests == RT_ELEMENTS(apReqs))
759	{
760	rc = pdmacFileAioMgrNormalReqsEnqueue(pAioMgr, pEndpoint, apReqs, cRequests);
761	cRequests = 0;
762	AssertMsg(RT_SUCCESS(rc) \|\| (rc == VERR_FILE_AIO_INSUFFICIENT_RESSOURCES),
763	("Unexpected return code\n"));
764	}
765	}
766	break;
767	}
768	default:
769	AssertMsgFailed(("Invalid transfer type %d\n", pCurr->enmTransferType));
770	}
771	}
772
773	if (cRequests)
774	{
775	rc = pdmacFileAioMgrNormalReqsEnqueue(pAioMgr, pEndpoint, apReqs, cRequests);
776	AssertMsg(RT_SUCCESS(rc) \|\| (rc == VERR_FILE_AIO_INSUFFICIENT_RESSOURCES),
777	("Unexpected return code rc=%Rrc\n", rc));
778	}
779
780	if (pTaskHead)
781	{
782	/* Add the rest of the tasks to the pending list */
783	pdmacFileAioMgrEpAddTaskList(pEndpoint, pTaskHead);
784
785	if (RT_UNLIKELY( !cMaxRequests
786	&& !pEndpoint->pFlushReq
787	&& !pAioMgr->fBwLimitReached))
788	{
789	/*
790	* The I/O manager has no room left for more requests
791	* but there are still requests to process.
792	* Create a new I/O manager and let it handle some endpoints.
793	*/
794	pdmacFileAioMgrNormalBalanceLoad(pAioMgr);
795	}
796	}
797
798	/* Insufficient resources are not fatal. */
799	if (rc == VERR_FILE_AIO_INSUFFICIENT_RESSOURCES)
800	rc = VINF_SUCCESS;
801
802	return rc;
803	}
804
805	/**
806	* Adds all pending requests for the given endpoint
807	* until a flush request is encountered or there is no
808	* request anymore.
809	*
810	* @returns VBox status code.
811	* @param pAioMgr The async I/O manager for the endpoint
812	* @param pEndpoint The endpoint to get the requests from.
813	*/
814	static int pdmacFileAioMgrNormalQueueReqs(PPDMACEPFILEMGR pAioMgr,
815	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
816	{
817	int rc = VINF_SUCCESS;
818	PPDMACTASKFILE pTasksHead = NULL;
819
820	AssertMsg(pEndpoint->enmState == PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE,
821	("Trying to process request lists of a non active endpoint!\n"));
822
823	Assert(!pEndpoint->pFlushReq);
824
825	/* Check the pending list first */
826	if (pEndpoint->AioMgr.pReqsPendingHead)
827	{
828	LogFlow(("Queuing pending requests first\n"));
829
830	pTasksHead = pEndpoint->AioMgr.pReqsPendingHead;
831	/*
832	* Clear the list as the processing routine will insert them into the list
833	* again if it gets a flush request.
834	*/
835	pEndpoint->AioMgr.pReqsPendingHead = NULL;
836	pEndpoint->AioMgr.pReqsPendingTail = NULL;
837	rc = pdmacFileAioMgrNormalProcessTaskList(pTasksHead, pAioMgr, pEndpoint);
838	AssertRC(rc);
839	}
840
841	if (!pEndpoint->pFlushReq && !pEndpoint->AioMgr.pReqsPendingHead)
842	{
843	/* Now the request queue. */
844	pTasksHead = pdmacFileEpGetNewTasks(pEndpoint);
845	if (pTasksHead)
846	{
847	rc = pdmacFileAioMgrNormalProcessTaskList(pTasksHead, pAioMgr, pEndpoint);
848	AssertRC(rc);
849	}
850	}
851
852	return rc;
853	}
854
855	static int pdmacFileAioMgrNormalProcessBlockingEvent(PPDMACEPFILEMGR pAioMgr)
856	{
857	int rc = VINF_SUCCESS;
858	bool fNotifyWaiter = false;
859
860	LogFlowFunc((": Enter\n"));
861
862	Assert(pAioMgr->fBlockingEventPending);
863
864	switch (pAioMgr->enmBlockingEvent)
865	{
866	case PDMACEPFILEAIOMGRBLOCKINGEVENT_ADD_ENDPOINT:
867	{
868	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointNew = (PPDMASYNCCOMPLETIONENDPOINTFILE)ASMAtomicReadPtr((void * volatile *)&pAioMgr->BlockingEventData.AddEndpoint.pEndpoint);
869	AssertMsg(VALID_PTR(pEndpointNew), ("Adding endpoint event without a endpoint to add\n"));
870
871	pEndpointNew->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE;
872
873	pEndpointNew->AioMgr.pEndpointNext = pAioMgr->pEndpointsHead;
874	pEndpointNew->AioMgr.pEndpointPrev = NULL;
875	if (pAioMgr->pEndpointsHead)
876	pAioMgr->pEndpointsHead->AioMgr.pEndpointPrev = pEndpointNew;
877	pAioMgr->pEndpointsHead = pEndpointNew;
878
879	/* Assign the completion point to this file. */
880	rc = RTFileAioCtxAssociateWithFile(pAioMgr->hAioCtx, pEndpointNew->File);
881	fNotifyWaiter = true;
882	pAioMgr->cEndpoints++;
883	break;
884	}
885	case PDMACEPFILEAIOMGRBLOCKINGEVENT_REMOVE_ENDPOINT:
886	{
887	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointRemove = (PPDMASYNCCOMPLETIONENDPOINTFILE)ASMAtomicReadPtr((void * volatile *)&pAioMgr->BlockingEventData.RemoveEndpoint.pEndpoint);
888	AssertMsg(VALID_PTR(pEndpointRemove), ("Removing endpoint event without a endpoint to remove\n"));
889
890	pEndpointRemove->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_REMOVING;
891	fNotifyWaiter = !pdmacFileAioMgrNormalRemoveEndpoint(pEndpointRemove);
892	break;
893	}
894	case PDMACEPFILEAIOMGRBLOCKINGEVENT_CLOSE_ENDPOINT:
895	{
896	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointClose = (PPDMASYNCCOMPLETIONENDPOINTFILE)ASMAtomicReadPtr((void * volatile *)&pAioMgr->BlockingEventData.CloseEndpoint.pEndpoint);
897	AssertMsg(VALID_PTR(pEndpointClose), ("Close endpoint event without a endpoint to close\n"));
898
899	if (pEndpointClose->enmState == PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE)
900	{
901	LogFlowFunc((": Closing endpoint %#p{%s}\n", pEndpointClose, pEndpointClose->Core.pszUri));
902
903	/* Make sure all tasks finished. Process the queues a last time first. */
904	rc = pdmacFileAioMgrNormalQueueReqs(pAioMgr, pEndpointClose);
905	AssertRC(rc);
906
907	pEndpointClose->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_CLOSING;
908	fNotifyWaiter = !pdmacFileAioMgrNormalRemoveEndpoint(pEndpointClose);
909	}
910	else if ( (pEndpointClose->enmState == PDMASYNCCOMPLETIONENDPOINTFILESTATE_CLOSING)
911	&& (!pEndpointClose->AioMgr.cRequestsActive))
912	fNotifyWaiter = true;
913	break;
914	}
915	case PDMACEPFILEAIOMGRBLOCKINGEVENT_SHUTDOWN:
916	{
917	pAioMgr->enmState = PDMACEPFILEMGRSTATE_SHUTDOWN;
918	if (!pAioMgr->cRequestsActive)
919	fNotifyWaiter = true;
920	break;
921	}
922	case PDMACEPFILEAIOMGRBLOCKINGEVENT_SUSPEND:
923	{
924	pAioMgr->enmState = PDMACEPFILEMGRSTATE_SUSPENDING;
925	break;
926	}
927	case PDMACEPFILEAIOMGRBLOCKINGEVENT_RESUME:
928	{
929	pAioMgr->enmState = PDMACEPFILEMGRSTATE_RUNNING;
930	fNotifyWaiter = true;
931	break;
932	}
933	default:
934	AssertReleaseMsgFailed(("Invalid event type %d\n", pAioMgr->enmBlockingEvent));
935	}
936
937	if (fNotifyWaiter)
938	{
939	ASMAtomicWriteBool(&pAioMgr->fBlockingEventPending, false);
940	pAioMgr->enmBlockingEvent = PDMACEPFILEAIOMGRBLOCKINGEVENT_INVALID;
941
942	/* Release the waiting thread. */
943	LogFlow(("Signalling waiter\n"));
944	rc = RTSemEventSignal(pAioMgr->EventSemBlock);
945	AssertRC(rc);
946	}
947
948	LogFlowFunc((": Leave\n"));
949	return rc;
950	}
951
952	/**
953	* Checks all endpoints for pending events or new requests.
954	*
955	* @returns VBox status code.
956	* @param pAioMgr The I/O manager handle.
957	*/
958	static int pdmacFileAioMgrNormalCheckEndpoints(PPDMACEPFILEMGR pAioMgr)
959	{
960	/* Check the assigned endpoints for new tasks if there isn't a flush request active at the moment. */
961	int rc = VINF_SUCCESS;
962	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint = pAioMgr->pEndpointsHead;
963
964	pAioMgr->fBwLimitReached = false;
965
966	while (pEndpoint)
967	{
968	if (!pEndpoint->pFlushReq
969	&& (pEndpoint->enmState == PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE)
970	&& !pEndpoint->AioMgr.fMoving)
971	{
972	rc = pdmacFileAioMgrNormalQueueReqs(pAioMgr, pEndpoint);
973	if (RT_FAILURE(rc))
974	return rc;
975	}
976	else if (!pEndpoint->AioMgr.cRequestsActive)
977	{
978	/* Reopen the file so that the new endpoint can reassociate with the file */
979	RTFileClose(pEndpoint->File);
980	rc = RTFileOpen(&pEndpoint->File, pEndpoint->Core.pszUri, pEndpoint->fFlags);
981	AssertRC(rc);
982
983	if (pEndpoint->AioMgr.fMoving)
984	{
985	pEndpoint->AioMgr.fMoving = false;
986	pdmacFileAioMgrAddEndpoint(pEndpoint->AioMgr.pAioMgrDst, pEndpoint);
987	}
988	else
989	{
990	Assert(pAioMgr->fBlockingEventPending);
991	ASMAtomicWriteBool(&pAioMgr->fBlockingEventPending, false);
992
993	/* Release the waiting thread. */
994	LogFlow(("Signalling waiter\n"));
995	rc = RTSemEventSignal(pAioMgr->EventSemBlock);
996	AssertRC(rc);
997	}
998	}
999
1000	pEndpoint = pEndpoint->AioMgr.pEndpointNext;
1001	}
1002
1003	return rc;
1004	}
1005
1006	static void pdmacFileAioMgrNormalReqComplete(PPDMACEPFILEMGR pAioMgr, RTFILEAIOREQ hReq)
1007	{
1008	int rc = VINF_SUCCESS;
1009	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint;
1010	size_t cbTransfered = 0;
1011	int rcReq = RTFileAioReqGetRC(hReq, &cbTransfered);
1012	PPDMACTASKFILE pTask = (PPDMACTASKFILE)RTFileAioReqGetUser(hReq);
1013
1014	pEndpoint = pTask->pEndpoint;
1015
1016	/*
1017	* It is possible that the request failed on Linux with kernels < 2.6.23
1018	* if the passed buffer was allocated with remap_pfn_range or if the file
1019	* is on an NFS endpoint which does not support async and direct I/O at the same time.
1020	* The endpoint will be migrated to a failsafe manager in case a request fails.
1021	*/
1022	if (RT_FAILURE(rcReq))
1023	{
1024	/* Free bounce buffers and the IPRT request. */
1025	pAioMgr->pahReqsFree[pAioMgr->iFreeEntryNext] = hReq;
1026	pAioMgr->iFreeEntryNext = (pAioMgr->iFreeEntryNext + 1) % pAioMgr->cReqEntries;
1027
1028	pAioMgr->cRequestsActive--;
1029	pEndpoint->AioMgr.cRequestsActive--;
1030	pEndpoint->AioMgr.cReqsProcessed++;
1031
1032	if (pTask->fBounceBuffer)
1033	RTMemFree(pTask->pvBounceBuffer);
1034
1035	/* Queue the request on the pending list. */
1036	pTask->pNext = pEndpoint->AioMgr.pReqsPendingHead;
1037	pEndpoint->AioMgr.pReqsPendingHead = pTask;
1038
1039	/* Create a new failsafe manager if neccessary. */
1040	if (!pEndpoint->AioMgr.fMoving)
1041	{
1042	PPDMACEPFILEMGR pAioMgrFailsafe;
1043
1044	LogRel(("%s: Request %#p failed with rc=%Rrc, migrating endpoint %s to failsafe manager.\n",
1045	RTThreadGetName(pAioMgr->Thread), pTask, rcReq, pEndpoint->Core.pszUri));
1046
1047	pEndpoint->AioMgr.fMoving = true;
1048
1049	rc = pdmacFileAioMgrCreate((PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->Core.pEpClass,
1050	&pAioMgrFailsafe, true);
1051	AssertRC(rc);
1052
1053	pEndpoint->AioMgr.pAioMgrDst = pAioMgrFailsafe;
1054
1055	/* Update the flags to open the file with. Disable async I/O and enable the host cache. */
1056	pEndpoint->fFlags &= ~(RTFILE_O_ASYNC_IO \| RTFILE_O_NO_CACHE);
1057	}
1058
1059	/* If this was the last request for the endpoint migrate it to the new manager. */
1060	if (!pEndpoint->AioMgr.cRequestsActive)
1061	{
1062	bool fReqsPending = pdmacFileAioMgrNormalRemoveEndpoint(pEndpoint);
1063	Assert(!fReqsPending);
1064
1065	rc = pdmacFileAioMgrAddEndpoint(pEndpoint->AioMgr.pAioMgrDst, pEndpoint);
1066	AssertRC(rc);
1067	}
1068	}
1069	else
1070	{
1071	AssertMsg(( (cbTransfered == pTask->DataSeg.cbSeg)
1072	\|\| (pTask->fBounceBuffer && (cbTransfered >= pTask->DataSeg.cbSeg))),
1073	("Task didn't completed successfully (rc=%Rrc) or was incomplete (cbTransfered=%u)\n", rcReq, cbTransfered));
1074
1075	if (pTask->fPrefetch)
1076	{
1077	Assert(pTask->enmTransferType == PDMACTASKFILETRANSFER_WRITE);
1078	Assert(pTask->fBounceBuffer);
1079
1080	memcpy(((uint8_t *)pTask->pvBounceBuffer) + pTask->uBounceBufOffset,
1081	pTask->DataSeg.pvSeg,
1082	pTask->DataSeg.cbSeg);
1083
1084	/* Write it now. */
1085	pTask->fPrefetch = false;
1086	size_t cbToTransfer = RT_ALIGN_Z(pTask->DataSeg.cbSeg, 512);
1087	RTFOFF offStart = pTask->Off & ~(RTFOFF)(512-1);
1088
1089	/* Grow the file if needed. */
1090	if (RT_UNLIKELY((uint64_t)(pTask->Off + pTask->DataSeg.cbSeg) > pEndpoint->cbFile))
1091	{
1092	ASMAtomicWriteU64(&pEndpoint->cbFile, pTask->Off + pTask->DataSeg.cbSeg);
1093	RTFileSetSize(pEndpoint->File, pTask->Off + pTask->DataSeg.cbSeg);
1094	}
1095
1096	rc = RTFileAioReqPrepareWrite(hReq, pEndpoint->File,
1097	offStart, pTask->pvBounceBuffer, cbToTransfer, pTask);
1098	AssertRC(rc);
1099	rc = RTFileAioCtxSubmit(pAioMgr->hAioCtx, &hReq, 1);
1100	AssertRC(rc);
1101	}
1102	else
1103	{
1104	if (pTask->fBounceBuffer)
1105	{
1106	if (pTask->enmTransferType == PDMACTASKFILETRANSFER_READ)
1107	memcpy(pTask->DataSeg.pvSeg,
1108	((uint8_t *)pTask->pvBounceBuffer) + pTask->uBounceBufOffset,
1109	pTask->DataSeg.cbSeg);
1110
1111	RTMemPageFree(pTask->pvBounceBuffer);
1112	}
1113
1114	/* Put the entry on the free array */
1115	pAioMgr->pahReqsFree[pAioMgr->iFreeEntryNext] = hReq;
1116	pAioMgr->iFreeEntryNext = (pAioMgr->iFreeEntryNext + 1) % pAioMgr->cReqEntries;
1117
1118	pAioMgr->cRequestsActive--;
1119	pEndpoint->AioMgr.cRequestsActive--;
1120	pEndpoint->AioMgr.cReqsProcessed++;
1121
1122	/* Free the lock and process pending tasks if neccessary */
1123	pdmacFileAioMgrNormalRangeLockFree(pAioMgr, pEndpoint, pTask->pRangeLock);
1124
1125	/* Call completion callback */
1126	pTask->pfnCompleted(pTask, pTask->pvUser);
1127	pdmacFileTaskFree(pEndpoint, pTask);
1128
1129	/*
1130	* If there is no request left on the endpoint but a flush request is set
1131	* it completed now and we notify the owner.
1132	* Furthermore we look for new requests and continue.
1133	*/
1134	if (!pEndpoint->AioMgr.cRequestsActive && pEndpoint->pFlushReq)
1135	{
1136	/* Call completion callback */
1137	pTask = pEndpoint->pFlushReq;
1138	pEndpoint->pFlushReq = NULL;
1139
1140	AssertMsg(pTask->pEndpoint == pEndpoint, ("Endpoint of the flush request does not match assigned one\n"));
1141
1142	pTask->pfnCompleted(pTask, pTask->pvUser);
1143	pdmacFileTaskFree(pEndpoint, pTask);
1144	}
1145	else if (RT_UNLIKELY(!pEndpoint->AioMgr.cRequestsActive && pEndpoint->AioMgr.fMoving))
1146	{
1147	/* If the endpoint is about to be migrated do it now. */
1148	bool fReqsPending = pdmacFileAioMgrNormalRemoveEndpoint(pEndpoint);
1149	Assert(!fReqsPending);
1150
1151	rc = pdmacFileAioMgrAddEndpoint(pEndpoint->AioMgr.pAioMgrDst, pEndpoint);
1152	AssertRC(rc);
1153	}
1154	}
1155	} /* request completed successfully */
1156	}
1157
1158	/** Helper macro for checking for error codes. */
1159	#define CHECK_RC(pAioMgr, rc) \
1160	if (RT_FAILURE(rc)) \
1161	{\
1162	int rc2 = pdmacFileAioMgrNormalErrorHandler(pAioMgr, rc, RT_SRC_POS);\
1163	return rc2;\
1164	}
1165
1166	/**
1167	* The normal I/O manager using the RTFileAio* API
1168	*
1169	* @returns VBox status code.
1170	* @param ThreadSelf Handle of the thread.
1171	* @param pvUser Opaque user data.
1172	*/
1173	int pdmacFileAioMgrNormal(RTTHREAD ThreadSelf, void *pvUser)
1174	{
1175	int rc = VINF_SUCCESS;
1176	PPDMACEPFILEMGR pAioMgr = (PPDMACEPFILEMGR)pvUser;
1177	uint64_t uMillisEnd = RTTimeMilliTS() + PDMACEPFILEMGR_LOAD_UPDATE_PERIOD;
1178
1179	while ( (pAioMgr->enmState == PDMACEPFILEMGRSTATE_RUNNING)
1180	\|\| (pAioMgr->enmState == PDMACEPFILEMGRSTATE_SUSPENDING))
1181	{
1182	ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, true);
1183	if (!ASMAtomicReadBool(&pAioMgr->fWokenUp))
1184	rc = RTSemEventWait(pAioMgr->EventSem, RT_INDEFINITE_WAIT);
1185	ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, false);
1186	AssertRC(rc);
1187
1188	LogFlow(("Got woken up\n"));
1189	ASMAtomicWriteBool(&pAioMgr->fWokenUp, false);
1190
1191	/* Check for an external blocking event first. */
1192	if (pAioMgr->fBlockingEventPending)
1193	{
1194	rc = pdmacFileAioMgrNormalProcessBlockingEvent(pAioMgr);
1195	CHECK_RC(pAioMgr, rc);
1196	}
1197
1198	if (RT_LIKELY(pAioMgr->enmState == PDMACEPFILEMGRSTATE_RUNNING))
1199	{
1200	/* We got woken up because an endpoint issued new requests. Queue them. */
1201	rc = pdmacFileAioMgrNormalCheckEndpoints(pAioMgr);
1202	CHECK_RC(pAioMgr, rc);
1203
1204	while ( pAioMgr->cRequestsActive
1205	\|\| pAioMgr->fBwLimitReached)
1206	{
1207	if (pAioMgr->cRequestsActive)
1208	{
1209	RTFILEAIOREQ apReqs[20];
1210	uint32_t cReqsCompleted = 0;
1211	size_t cReqsWait;
1212
1213	if (pAioMgr->cRequestsActive > RT_ELEMENTS(apReqs))
1214	cReqsWait = RT_ELEMENTS(apReqs);
1215	else
1216	cReqsWait = pAioMgr->cRequestsActive;
1217
1218	LogFlow(("Waiting for %d of %d tasks to complete\n", pAioMgr->cRequestsActive, cReqsWait));
1219
1220	rc = RTFileAioCtxWait(pAioMgr->hAioCtx,
1221	cReqsWait,
1222	RT_INDEFINITE_WAIT, apReqs,
1223	RT_ELEMENTS(apReqs), &cReqsCompleted);
1224	if (RT_FAILURE(rc) && (rc != VERR_INTERRUPTED))
1225	CHECK_RC(pAioMgr, rc);
1226
1227	LogFlow(("%d tasks completed\n", cReqsCompleted));
1228
1229	for (uint32_t i = 0; i < cReqsCompleted; i++)
1230	pdmacFileAioMgrNormalReqComplete(pAioMgr, apReqs[i]);
1231
1232	/* Check for an external blocking event before we go to sleep again. */
1233	if (pAioMgr->fBlockingEventPending)
1234	{
1235	rc = pdmacFileAioMgrNormalProcessBlockingEvent(pAioMgr);
1236	CHECK_RC(pAioMgr, rc);
1237	}
1238
1239	/* Update load statistics. */
1240	uint64_t uMillisCurr = RTTimeMilliTS();
1241	if (uMillisCurr > uMillisEnd)
1242	{
1243	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointCurr = pAioMgr->pEndpointsHead;
1244
1245	/* Calculate timespan. */
1246	uMillisCurr -= uMillisEnd;
1247
1248	while (pEndpointCurr)
1249	{
1250	pEndpointCurr->AioMgr.cReqsPerSec = pEndpointCurr->AioMgr.cReqsProcessed / (uMillisCurr + PDMACEPFILEMGR_LOAD_UPDATE_PERIOD);
1251	pEndpointCurr->AioMgr.cReqsProcessed = 0;
1252	pEndpointCurr = pEndpointCurr->AioMgr.pEndpointNext;
1253	}
1254
1255	/* Set new update interval */
1256	uMillisEnd = RTTimeMilliTS() + PDMACEPFILEMGR_LOAD_UPDATE_PERIOD;
1257	}
1258	}
1259	else
1260	{
1261	/*
1262	* Bandwidth limit reached for all endpoints.
1263	* Yield and wait until we have enough resources again.
1264	*/
1265	RTThreadYield();
1266	}
1267
1268	/* Check endpoints for new requests. */
1269	rc = pdmacFileAioMgrNormalCheckEndpoints(pAioMgr);
1270	CHECK_RC(pAioMgr, rc);
1271	} /* while requests are active. */
1272	} /* if still running */
1273	} /* while running */
1274
1275	return rc;
1276	}
1277
1278	#undef CHECK_RC
1279

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source: vbox/trunk/src/VBox/VMM/PDMAsyncCompletionFileNormal.cpp@ 26671

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