PDMAsyncCompletionFile.cpp@ 20368

Last change on this file since 20368 was 20168, checked in by vboxsync, 16 years ago
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1	/* $Id: PDMAsyncCompletionFile.cpp 20168 2009-06-01 20:31:31Z vboxsync $ */
2	/** @file
3	* PDM Async I/O - Transport data asynchronous in R3 using EMT.
4	*/
5
6	/*
7	* Copyright (C) 2006-2008 Sun Microsystems, Inc.
8	*
9	* This file is part of VirtualBox Open Source Edition (OSE), as
10	* available from http://www.virtualbox.org. This file is free software;
11	* you can redistribute it and/or modify it under the terms of the GNU
12	* General Public License (GPL) as published by the Free Software
13	* Foundation, in version 2 as it comes in the "COPYING" file of the
14	* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15	* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16	*
17	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
18	* Clara, CA 95054 USA or visit http://www.sun.com if you need
19	* additional information or have any questions.
20	*/
21
22
23
24	/*******************************************************************************
25	* Header Files *
26	*******************************************************************************/
27	#define LOG_GROUP LOG_GROUP_PDM_ASYNC_COMPLETION
28	#include "PDMInternal.h"
29	#include <VBox/pdm.h>
30	#include <VBox/mm.h>
31	#include <VBox/vm.h>
32	#include <VBox/err.h>
33
34	#include <VBox/log.h>
35	#include <iprt/asm.h>
36	#include <iprt/assert.h>
37	#include <iprt/thread.h>
38	#include <iprt/mem.h>
39	#include <iprt/critsect.h>
40	#include <iprt/file.h>
41	#include <iprt/semaphore.h>
42
43	#include "PDMAsyncCompletionInternal.h"
44
45	/** @todo: Revise the caching of tasks. We have currently four caches:
46	* Per endpoint task cache
47	* Per class cache
48	* Per endpoint task segment cache
49	* Per class task segment cache
50	*
51	* We could use the RT heap for this probably or extend MMR3Heap (uses RTMemAlloc
52	* instead of managing larger blocks) to have this global for the whole VM.
53	*/
54
55	/**
56	* A few forward declerations.
57	*/
58	typedef struct PDMASYNCCOMPLETIONENDPOINTFILE *PPDMASYNCCOMPLETIONENDPOINTFILE;
59	/** Pointer to a request segment. */
60	typedef struct PDMACTASKFILESEG *PPDMACTASKFILESEG;
61
62	/**
63	* Blocking event types.
64	*/
65	typedef enum PDMACEPFILEAIOMGRBLOCKINGEVENT
66	{
67	/** Invalid tye */
68	PDMACEPFILEAIOMGRBLOCKINGEVENT_INVALID = 0,
69	/** An endpoint is added to the manager. */
70	PDMACEPFILEAIOMGRBLOCKINGEVENT_ADD_ENDPOINT,
71	/** An endpoint is removed from the manager. */
72	PDMACEPFILEAIOMGRBLOCKINGEVENT_REMOVE_ENDPOINT,
73	/** An endpoint is about to be closed. */
74	PDMACEPFILEAIOMGRBLOCKINGEVENT_CLOSE_ENDPOINT,
75	/** The manager is requested to terminate */
76	PDMACEPFILEAIOMGRBLOCKINGEVENT_SHUTDOWN,
77	/** The manager is requested to suspend */
78	PDMACEPFILEAIOMGRBLOCKINGEVENT_SUSPEND,
79	/** 32bit hack */
80	PDMACEPFILEAIOMGRBLOCKINGEVENT_32BIT_HACK = 0x7fffffff
81	} PDMACEPFILEAIOMGRBLOCKINGEVENT;
82
83	/**
84	* State of a async I/O manager.
85	*/
86	typedef struct PDMACEPFILEMGR
87	{
88	/** Next Aio manager in the list. */
89	R3PTRTYPE(struct PDMACEPFILEMGR *) pNext;
90	/** Previous Aio manager in the list. */
91	R3PTRTYPE(struct PDMACEPFILEMGR *) pPrev;
92	/** Event semaphore the manager sleeps on when waiting for new requests. */
93	RTSEMEVENT EventSem;
94	/** Flag whether the thread waits in the event semaphore. */
95	volatile bool fWaitingEventSem;
96	/** Flag whether this manager uses the failsafe method. */
97	bool fFailsafe;
98	/** Flag whether the thread is waiting for I/O to complete. */
99	volatile bool fWaitingForIo;
100	/** Thread data */
101	RTTHREAD Thread;
102	/** Flag whether the I/O manager is requested to terminate */
103	volatile bool fShutdown;
104	/** Flag whether the I/O manager was woken up. */
105	volatile bool fWokenUp;
106	/** List of endpoints assigned to this manager. */
107	R3PTRTYPE(PPDMASYNCCOMPLETIONENDPOINTFILE) pEndpointsHead;
108	/** Critical section protecting the blocking event handling. */
109	RTCRITSECT CritSectBlockingEvent;
110	/** Event sempahore for blocking external events.
111	* The caller waits on it until the async I/O manager
112	* finished processing the event. */
113	RTSEMEVENT EventSemBlock;
114	/** Flag whether a blocking event is pending and needs
115	* processing by the I/O manager. */
116	bool fBlockingEventPending;
117	/** Blocking event type */
118	PDMACEPFILEAIOMGRBLOCKINGEVENT enmBlockingEvent;
119	/** Event type data */
120	union
121	{
122	/** Add endpoint event. */
123	struct
124	{
125	/** The endpoint to be added */
126	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint;
127	} AddEndpoint;
128	/** Remove endpoint event. */
129	struct
130	{
131	/** The endpoint to be added */
132	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint;
133	} RemoveEndpoint;
134	/** Close endpoint event. */
135	struct
136	{
137	/** The endpoint to be closed */
138	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint;
139	} CloseEndpoint;
140	} BlockingEventData;
141	} PDMACEPFILEMGR;
142	/** Pointer to a async I/O manager state. */
143	typedef PDMACEPFILEMGR *PPDMACEPFILEMGR;
144	/** Pointer to a async I/O manager state pointer. */
145	typedef PPDMACEPFILEMGR *PPPDMACEPFILEMGR;
146
147	/**
148	* Global data for the file endpoint class.
149	*/
150	typedef struct PDMASYNCCOMPLETIONEPCLASSFILE
151	{
152	/** Common data. */
153	PDMASYNCCOMPLETIONEPCLASS Core;
154	/** Flag whether we use the failsafe method. */
155	bool fFailsafe;
156	/** Critical section protecting the list of async I/O managers. */
157	RTCRITSECT CritSect;
158	/** Pointer to the head of the async I/O managers. */
159	R3PTRTYPE(PPDMACEPFILEMGR) pAioMgrHead;
160	/** Number of async I/O managers currently running. */
161	unsigned cAioMgrs;
162	/** Maximum number of segments to cache per endpoint */
163	unsigned cSegmentsCacheMax;
164	} PDMASYNCCOMPLETIONEPCLASSFILE;
165	/** Pointer to the endpoint class data. */
166	typedef PDMASYNCCOMPLETIONEPCLASSFILE *PPDMASYNCCOMPLETIONEPCLASSFILE;
167
168	typedef enum PDMACEPFILEBLOCKINGEVENT
169	{
170	/** The invalid event type */
171	PDMACEPFILEBLOCKINGEVENT_INVALID = 0,
172	/** A task is about to be canceled */
173	PDMACEPFILEBLOCKINGEVENT_CANCEL,
174	/** Usual 32bit hack */
175	PDMACEPFILEBLOCKINGEVENT_32BIT_HACK = 0x7fffffff
176	} PDMACEPFILEBLOCKINGEVENT;
177
178	/**
179	* Data for the file endpoint.
180	*/
181	typedef struct PDMASYNCCOMPLETIONENDPOINTFILE
182	{
183	/** Common data. */
184	PDMASYNCCOMPLETIONENDPOINT Core;
185	/** async I/O manager this endpoint is assigned to. */
186	R3PTRTYPE(PPDMACEPFILEMGR) pAioMgr;
187	/** File handle. */
188	RTFILE File;
189	/** Flag whether caching is enabled for this file. */
190	bool fCaching;
191	/** List of new tasks. */
192	R3PTRTYPE(volatile PPDMASYNCCOMPLETIONTASK) pTasksNewHead;
193
194	/** Head of the small cache for allocated task segments for exclusive
195	* use by this endpoint. */
196	R3PTRTYPE(volatile PPDMACTASKFILESEG) pSegmentsFreeHead;
197	/** Tail of the small cache for allocated task segments for exclusive
198	* use by this endpoint. */
199	R3PTRTYPE(volatile PPDMACTASKFILESEG) pSegmentsFreeTail;
200	/** Number of elements in the cache. */
201	volatile uint32_t cSegmentsCached;
202
203	/** Event sempahore for blocking external events.
204	* The caller waits on it until the async I/O manager
205	* finished processing the event. */
206	RTSEMEVENT EventSemBlock;
207	/** Flag whether a blocking event is pending and needs
208	* processing by the I/O manager. */
209	bool fBlockingEventPending;
210	/** Blocking event type */
211	PDMACEPFILEBLOCKINGEVENT enmBlockingEvent;
212	/** Additional data needed for the event types. */
213	union
214	{
215	/** Cancelation event. */
216	struct
217	{
218	/** The task to cancel. */
219	PPDMASYNCCOMPLETIONTASK pTask;
220	} Cancel;
221	} BlockingEventData;
222	/** Data for exclusive use by the assigned async I/O manager. */
223	struct
224	{
225	/** Pointer to the next endpoint assigned to the manager. */
226	R3PTRTYPE(PPDMASYNCCOMPLETIONENDPOINTFILE) pEndpointNext;
227	/** Pointer to the previous endpoint assigned to the manager. */
228	R3PTRTYPE(PPDMASYNCCOMPLETIONENDPOINTFILE) pEndpointPrev;
229	} AioMgr;
230	} PDMASYNCCOMPLETIONENDPOINTFILE;
231	/** Pointer to the endpoint class data. */
232	typedef PDMASYNCCOMPLETIONENDPOINTFILE *PPDMASYNCCOMPLETIONENDPOINTFILE;
233
234	/**
235	* Segment data of a request.
236	*/
237	typedef struct PDMACTASKFILESEG
238	{
239	/** Pointer to the next segment in the list. */
240	R3PTRTYPE(struct PDMACTASKFILESEG *) pNext;
241	/** Pointer to the previous segment in the list. */
242	R3PTRTYPE(struct PDMACTASKFILESEG *) pPrev;
243	/** Data for the filesafe and normal manager. */
244	union
245	{
246	/** AIO request */
247	RTFILEAIOREQ AioReq;
248	/** Data for the failsafe manager. */
249	struct
250	{
251	/** Flag whether this is a re request. False for write */
252	bool fRead;
253	/** Offset to start from */
254	RTFOFF off;
255	/** Size of the transfer */
256	size_t cbTransfer;
257	/** Pointer to the buffer. */
258	void *pvBuf;
259	} Failsafe;
260	} u;
261	} PDMACTASKFILESEG;
262
263	/**
264	* Per task data.
265	*/
266	typedef struct PDMASYNCCOMPLETIONTASKFILE
267	{
268	/** Common data. */
269	PDMASYNCCOMPLETIONTASK Core;
270	/** Flag whether this is a flush request. */
271	bool fFlush;
272	/** Type dependent data. */
273	union
274	{
275	/** AIO request for the flush. */
276	RTFILEAIOREQ AioReq;
277	/** Data for a data transfer */
278	struct
279	{
280	/** Number of segments which still needs to be processed before the task
281	* completes. */
282	unsigned cSegments;
283	/** Head of the request segments list for read and write requests. */
284	PPDMACTASKFILESEG pSegmentsHead;
285	} DataTransfer;
286	} u;
287	} PDMASYNCCOMPLETIONTASKFILE;
288	/** Pointer to the endpoint class data. */
289	typedef PDMASYNCCOMPLETIONTASKFILE *PPDMASYNCCOMPLETIONTASKFILE;
290
291	/**
292	* Frees a task segment
293	*
294	* @returns nothing.
295	* @param pEndpoint Pointer to the endpoint the segment was for.
296	* @param pSeg The segment to free.
297	*/
298	static void pdmacFileSegmentFree(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint,
299	PPDMACTASKFILESEG pSeg)
300	{
301	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClass = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->Core.pEpClass;
302
303	LogFlowFunc((": pEndpoint=%p pSeg=%p\n", pEndpoint, pSeg));
304
305	/* Try the per endpoint cache first. */
306	if (pEndpoint->cSegmentsCached < pEpClass->cSegmentsCacheMax)
307	{
308	/* Add it to the list. */
309	pSeg->pPrev = NULL;
310	pEndpoint->pSegmentsFreeTail->pNext = pSeg;
311	pEndpoint->pSegmentsFreeTail = pSeg;
312	ASMAtomicIncU32(&pEndpoint->cSegmentsCached);
313	}
314	else if (false)
315	{
316	/* Bigger class cache */
317	}
318	else
319	{
320	Log(("Freeing segment %p because all caches are full\n", pSeg));
321	MMR3HeapFree(pSeg);
322	}
323	}
324
325	/**
326	* Allocates a task segment
327	*
328	* @returns Pointer to the new task segment or NULL
329	* @param pEndpoint Pointer to the endpoint
330	*/
331	static PPDMACTASKFILESEG pdmacFileSegmentAlloc(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
332	{
333	PPDMACTASKFILESEG pSeg = NULL;
334
335	/* Try the small per endpoint cache first. */
336	if (pEndpoint->pSegmentsFreeHead == pEndpoint->pSegmentsFreeTail)
337	{
338	/* Try the bigger endpoint class cache. */
339	PPDMASYNCCOMPLETIONEPCLASSFILE pEndpointClass = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->Core.pEpClass;
340
341	#if 0
342	/* We start with the assigned slot id to distribute the load when allocating new tasks. */
343	unsigned iSlot = pEndpoint->iSlotStart;
344	do
345	{
346	pTask = (PPDMASYNCCOMPLETIONTASK)ASMAtomicXchgPtr((void * volatile *)&pEndpointClass->apTaskCache[iSlot], NULL);
347	if (pTask)
348	break;
349
350	iSlot = (iSlot + 1) % RT_ELEMENTS(pEndpointClass->apTaskCache);
351	} while (iSlot != pEndpoint->iSlotStart);
352	#endif
353	if (!pSeg)
354	{
355	/*
356	* Allocate completely new.
357	* If this fails we return NULL.
358	*/
359	int rc = MMR3HeapAllocZEx(pEndpointClass->Core.pVM, MM_TAG_PDM_ASYNC_COMPLETION,
360	sizeof(PDMACTASKFILESEG),
361	(void **)&pSeg);
362	if (RT_FAILURE(rc))
363	pSeg = NULL;
364
365	LogFlow(("Allocated segment %p\n", pSeg));
366	}
367	#if 0
368	else
369	{
370	/* Remove the first element and put the rest into the slot again. */
371	PPDMASYNCCOMPLETIONTASK pTaskHeadNew = pTask->pNext;
372
373	pTaskHeadNew->pPrev = NULL;
374
375	/* Put back into the list adding any new tasks. */
376	while (true)
377	{
378	bool fChanged = ASMAtomicCmpXchgPtr((void * volatile *)&pEndpointClass->apTaskCache[iSlot], pTaskHeadNew, NULL);
379
380	if (fChanged)
381	break;
382
383	PPDMASYNCCOMPLETIONTASK pTaskHead = (PPDMASYNCCOMPLETIONTASK)ASMAtomicXchgPtr((void * volatile *)&pEndpointClass->apTaskCache[iSlot], NULL);
384
385	/* The new task could be taken inbetween */
386	if (pTaskHead)
387	{
388	/* Go to the end of the probably much shorter new list. */
389	PPDMASYNCCOMPLETIONTASK pTaskTail = pTaskHead;
390	while (pTaskTail->pNext)
391	pTaskTail = pTaskTail->pNext;
392
393	/* Concatenate */
394	pTaskTail->pNext = pTaskHeadNew;
395
396	pTaskHeadNew = pTaskHead;
397	}
398	/* Another round trying to change the list. */
399	}
400	/* We got a task from the global cache so decrement the counter */
401	ASMAtomicDecU32(&pEndpointClass->cTasksCached);
402	}
403	#endif
404	}
405	else
406	{
407	/* Grab a free task from the head. */
408	AssertMsg(pEndpoint->cSegmentsCached > 0, ("No segments cached but list contains more than one element\n"));
409
410	pSeg = pEndpoint->pSegmentsFreeHead;
411	pEndpoint->pSegmentsFreeHead = pSeg->pNext;
412	ASMAtomicDecU32(&pEndpoint->cSegmentsCached);
413	}
414
415	pSeg->pNext = NULL;
416	pSeg->pPrev = NULL;
417
418	return pSeg;
419	}
420
421	static PPDMASYNCCOMPLETIONTASK pdmacFileEpGetNewTasks(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
422	{
423	PPDMASYNCCOMPLETIONTASK pTasks = NULL;
424
425	/*
426	* Get pending tasks.
427	*/
428	pTasks = (PPDMASYNCCOMPLETIONTASK)ASMAtomicXchgPtr((void * volatile *)&pEndpoint->pTasksNewHead, NULL);
429
430	/* Reverse the list to process in FIFO order. */
431	if (pTasks)
432	{
433	PPDMASYNCCOMPLETIONTASK pTask = pTasks;
434
435	pTasks = NULL;
436
437	while (pTask)
438	{
439	PPDMASYNCCOMPLETIONTASK pCur = pTask;
440	pTask = pTask->pNext;
441	pCur->pNext = pTasks;
442	pTasks = pCur;
443	}
444	}
445
446	return pTasks;
447	}
448
449	static int pdmacFileAioMgrFailsafeProcessEndpoint(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
450	{
451	int rc = VINF_SUCCESS;
452	PPDMASYNCCOMPLETIONTASK pTasks = pdmacFileEpGetNewTasks(pEndpoint);
453
454	while (pTasks)
455	{
456	PPDMASYNCCOMPLETIONTASKFILE pTaskFile = (PPDMASYNCCOMPLETIONTASKFILE)pTasks;
457
458	if (pTasks->pNext)
459	AssertMsg(pTasks->uTaskId < pTasks->pNext->uTaskId,
460	("The task IDs are not ordered Curr=%u Next=%u\n", pTasks->uTaskId, pTasks->pNext->uTaskId));
461
462	if (pTaskFile->fFlush)
463	{
464	rc = RTFileFlush(pEndpoint->File);
465	}
466	else
467	{
468	PPDMACTASKFILESEG pSeg = pTaskFile->u.DataTransfer.pSegmentsHead;
469
470	while(pSeg)
471	{
472	if (pSeg->u.Failsafe.fRead)
473	{
474	rc = RTFileReadAt(pEndpoint->File, pSeg->u.Failsafe.off,
475	pSeg->u.Failsafe.pvBuf,
476	pSeg->u.Failsafe.cbTransfer,
477	NULL);
478	}
479	else
480	{
481	rc = RTFileWriteAt(pEndpoint->File, pSeg->u.Failsafe.off,
482	pSeg->u.Failsafe.pvBuf,
483	pSeg->u.Failsafe.cbTransfer,
484	NULL);
485	}
486
487	/* Free the segment. */
488	PPDMACTASKFILESEG pCur = pSeg;
489	pSeg = pSeg->pNext;
490
491	pdmacFileSegmentFree(pEndpoint, pCur);
492	}
493	}
494
495	AssertRC(rc);
496	pTasks = pTasks->pNext;
497
498	/* Notify task owner */
499	pdmR3AsyncCompletionCompleteTask(&pTaskFile->Core);
500	}
501
502	return rc;
503	}
504
505	/**
506	* A fallback method in case something goes wrong with the normal
507	* I/O manager.
508	*/
509	static int pdmacFileAioMgrFailsafe(RTTHREAD ThreadSelf, void *pvUser)
510	{
511	int rc = VINF_SUCCESS;
512	PPDMACEPFILEMGR pAioMgr = (PPDMACEPFILEMGR)pvUser;
513
514	while (!pAioMgr->fShutdown)
515	{
516	if (!ASMAtomicReadBool(&pAioMgr->fWokenUp))
517	{
518	ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, true);
519	rc = RTSemEventWait(pAioMgr->EventSem, RT_INDEFINITE_WAIT);
520	ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, false);
521	AssertRC(rc);
522	}
523	ASMAtomicXchgBool(&pAioMgr->fWokenUp, false);
524
525	/* Process endpoint events first. */
526	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint = pAioMgr->pEndpointsHead;
527	while (pEndpoint)
528	{
529	rc = pdmacFileAioMgrFailsafeProcessEndpoint(pEndpoint);
530	AssertRC(rc);
531	pEndpoint = pEndpoint->AioMgr.pEndpointNext;
532	}
533
534	/* Now check for an external blocking event. */
535	if (pAioMgr->fBlockingEventPending)
536	{
537	switch (pAioMgr->enmBlockingEvent)
538	{
539	case PDMACEPFILEAIOMGRBLOCKINGEVENT_ADD_ENDPOINT:
540	{
541	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointNew = pAioMgr->BlockingEventData.AddEndpoint.pEndpoint;
542	AssertMsg(VALID_PTR(pEndpointNew), ("Adding endpoint event without a endpoint to add\n"));
543
544	pEndpointNew->AioMgr.pEndpointNext = pAioMgr->pEndpointsHead;
545	pEndpointNew->AioMgr.pEndpointPrev = NULL;
546	if (pAioMgr->pEndpointsHead)
547	pAioMgr->pEndpointsHead->AioMgr.pEndpointPrev = pEndpointNew;
548	pAioMgr->pEndpointsHead = pEndpointNew;
549	break;
550	}
551	case PDMACEPFILEAIOMGRBLOCKINGEVENT_REMOVE_ENDPOINT:
552	{
553	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointRemove = pAioMgr->BlockingEventData.RemoveEndpoint.pEndpoint;
554	AssertMsg(VALID_PTR(pEndpointRemove), ("Removing endpoint event without a endpoint to remove\n"));
555
556	PPDMASYNCCOMPLETIONENDPOINTFILE pPrev = pEndpointRemove->AioMgr.pEndpointPrev;
557	PPDMASYNCCOMPLETIONENDPOINTFILE pNext = pEndpointRemove->AioMgr.pEndpointNext;
558
559	if (pPrev)
560	pPrev->AioMgr.pEndpointNext = pNext;
561	else
562	pAioMgr->pEndpointsHead = pNext;
563
564	if (pNext)
565	pNext->AioMgr.pEndpointPrev = pPrev;
566	break;
567	}
568	case PDMACEPFILEAIOMGRBLOCKINGEVENT_CLOSE_ENDPOINT:
569	{
570	PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointClose = pAioMgr->BlockingEventData.CloseEndpoint.pEndpoint;
571	AssertMsg(VALID_PTR(pEndpointClose), ("Close endpoint event without a endpoint to Close\n"));
572
573	/* Make sure all tasks finished. */
574	rc = pdmacFileAioMgrFailsafeProcessEndpoint(pEndpointClose);
575	AssertRC(rc);
576	}
577	case PDMACEPFILEAIOMGRBLOCKINGEVENT_SHUTDOWN:
578	break;
579	case PDMACEPFILEAIOMGRBLOCKINGEVENT_SUSPEND:
580	break;
581	default:
582	AssertMsgFailed(("Invalid event type %d\n", pAioMgr->enmBlockingEvent));
583	}
584
585	/* Release the waiting thread. */
586	rc = RTSemEventSignal(pAioMgr->EventSemBlock);
587	AssertRC(rc);
588	}
589	}
590
591	return rc;
592	}
593
594	static int pdmacFileAioMgrNormal(RTTHREAD ThreadSelf, void *pvUser)
595	{
596	AssertMsgFailed(("Implement\n"));
597	return VERR_NOT_IMPLEMENTED;
598	}
599
600	static void pdmacFileAioMgrWakeup(PPDMACEPFILEMGR pAioMgr)
601	{
602	bool fWokenUp = ASMAtomicXchgBool(&pAioMgr->fWokenUp, true);
603
604	if (!fWokenUp)
605	{
606	int rc = VINF_SUCCESS;
607	bool fWaitingEventSem = ASMAtomicReadBool(&pAioMgr->fWaitingEventSem);
608	bool fWaitingForIo = ASMAtomicReadBool(&pAioMgr->fWaitingForIo);
609
610	if (fWaitingEventSem)
611	rc = RTSemEventSignal(pAioMgr->EventSem);
612	#if 0 /** @todo When RTFileAio* is used */
613	else if (fWaitingForIo)
614	rc = RTThreadPoke(pAioMgr->Thread);
615	#endif
616
617	AssertRC(rc);
618	}
619	}
620
621	static int pdmacFileAioMgrWaitForBlockingEvent(PPDMACEPFILEMGR pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT enmEvent)
622	{
623	int rc = VINF_SUCCESS;
624
625	pAioMgr->enmBlockingEvent = enmEvent;
626	pAioMgr->fBlockingEventPending = true;
627
628	/* Wakeup the async I/O manager */
629	pdmacFileAioMgrWakeup(pAioMgr);
630
631	/* Wait for completion. */
632	rc = RTSemEventWait(pAioMgr->EventSemBlock, RT_INDEFINITE_WAIT);
633	AssertRC(rc);
634
635	pAioMgr->fBlockingEventPending = false;
636
637	return rc;
638	}
639
640	static int pdmacFileAioMgrAddEndpoint(PPDMACEPFILEMGR pAioMgr, PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
641	{
642	int rc;
643
644	rc = RTCritSectEnter(&pAioMgr->CritSectBlockingEvent);
645	AssertRCReturn(rc, rc);
646
647	pAioMgr->BlockingEventData.AddEndpoint.pEndpoint = pEndpoint;
648	rc = pdmacFileAioMgrWaitForBlockingEvent(pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT_ADD_ENDPOINT);
649
650	RTCritSectLeave(&pAioMgr->CritSectBlockingEvent);
651
652	return rc;
653	}
654
655	static int pdmacFileAioMgrRemoveEndpoint(PPDMACEPFILEMGR pAioMgr, PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
656	{
657	int rc;
658
659	rc = RTCritSectEnter(&pAioMgr->CritSectBlockingEvent);
660	AssertRCReturn(rc, rc);
661
662	pAioMgr->BlockingEventData.RemoveEndpoint.pEndpoint = pEndpoint;
663	rc = pdmacFileAioMgrWaitForBlockingEvent(pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT_REMOVE_ENDPOINT);
664
665	RTCritSectLeave(&pAioMgr->CritSectBlockingEvent);
666
667	return rc;
668	}
669
670	static int pdmacFileAioMgrCloseEndpoint(PPDMACEPFILEMGR pAioMgr, PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint)
671	{
672	int rc;
673
674	rc = RTCritSectEnter(&pAioMgr->CritSectBlockingEvent);
675	AssertRCReturn(rc, rc);
676
677	pAioMgr->BlockingEventData.CloseEndpoint.pEndpoint = pEndpoint;
678	rc = pdmacFileAioMgrWaitForBlockingEvent(pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT_CLOSE_ENDPOINT);
679
680	RTCritSectLeave(&pAioMgr->CritSectBlockingEvent);
681
682	return rc;
683	}
684
685	static int pdmacFileAioMgrShutdown(PPDMACEPFILEMGR pAioMgr)
686	{
687	int rc;
688
689	ASMAtomicXchgBool(&pAioMgr->fShutdown, true);
690
691	rc = RTCritSectEnter(&pAioMgr->CritSectBlockingEvent);
692	AssertRCReturn(rc, rc);
693
694	rc = pdmacFileAioMgrWaitForBlockingEvent(pAioMgr, PDMACEPFILEAIOMGRBLOCKINGEVENT_SHUTDOWN);
695
696	RTCritSectLeave(&pAioMgr->CritSectBlockingEvent);
697
698	return rc;
699	}
700
701	static int pdmacFileEpAddTask(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint, PPDMASYNCCOMPLETIONTASKFILE pTask)
702	{
703	PPDMASYNCCOMPLETIONTASK pNext;
704	do
705	{
706	pNext = pEndpoint->pTasksNewHead;
707	pTask->Core.pNext = pNext;
708	} while (!ASMAtomicCmpXchgPtr((void * volatile )&pEndpoint->pTasksNewHead, (void )pTask, (void *)pNext));
709
710	pdmacFileAioMgrWakeup(pEndpoint->pAioMgr);
711
712	return VINF_SUCCESS;
713	}
714
715	static int pdmacFileEpTaskInitiate(PPDMASYNCCOMPLETIONTASK pTask,
716	PPDMASYNCCOMPLETIONENDPOINT pEndpoint, RTFOFF off,
717	PCPDMDATASEG paSegments, size_t cSegments,
718	size_t cbTransfer, bool fRead)
719	{
720	int rc = VINF_SUCCESS;
721	PPDMASYNCCOMPLETIONENDPOINTFILE pEpFile = (PPDMASYNCCOMPLETIONENDPOINTFILE)pEndpoint;
722	PPDMASYNCCOMPLETIONTASKFILE pTaskFile = (PPDMASYNCCOMPLETIONTASKFILE)pTask;
723	PPDMACEPFILEMGR pAioMgr = pEpFile->pAioMgr;
724
725	Assert(pAioMgr->fFailsafe); /** @todo change */
726
727	pTaskFile->u.DataTransfer.cSegments = cSegments;
728	pTaskFile->u.DataTransfer.pSegmentsHead = NULL;
729
730	PPDMACTASKFILESEG pSeg = pdmacFileSegmentAlloc(pEpFile);
731
732	pTaskFile->u.DataTransfer.pSegmentsHead = pSeg;
733
734	for (unsigned i = 0; i < cSegments; i++)
735	{
736	pSeg->u.Failsafe.fRead = fRead;
737	pSeg->u.Failsafe.off = off;
738	pSeg->u.Failsafe.cbTransfer = paSegments[i].cbSeg;
739	pSeg->u.Failsafe.pvBuf = paSegments[i].pvSeg;
740
741	off += paSegments[i].cbSeg;
742	cbTransfer -= paSegments[i].cbSeg;
743
744	if (i < (cSegments-1))
745	{
746	/* Allocate new segment. */
747	PPDMACTASKFILESEG pSegNext = pdmacFileSegmentAlloc(pEpFile);
748	AssertPtr(pSeg);
749	pSeg->pNext = pSegNext;
750	pSeg = pSegNext;
751	}
752	}
753
754	AssertMsg(!cbTransfer, ("Incomplete task cbTransfer=%u\n", cbTransfer));
755
756	/* Send it off */
757	pdmacFileEpAddTask(pEpFile, pTaskFile);
758
759	return VINF_SUCCESS;
760	}
761
762	/**
763	* Creates a new async I/O manager.
764	*
765	* @returns VBox status code.
766	* @param pEpClass Pointer to the endpoint class data.
767	* @param ppAioMgr Where to store the pointer to the new async I/O manager on success.
768	*/
769	static int pdmacFileAioMgrCreate(PPDMASYNCCOMPLETIONEPCLASSFILE pEpClass, PPPDMACEPFILEMGR ppAioMgr)
770	{
771	int rc = VINF_SUCCESS;
772	PPDMACEPFILEMGR pAioMgrNew;
773
774	LogFlowFunc((": Entered\n"));
775
776	rc = MMR3HeapAllocZEx(pEpClass->Core.pVM, MM_TAG_PDM_ASYNC_COMPLETION, sizeof(PDMACEPFILEMGR), (void **)&pAioMgrNew);
777	if (RT_SUCCESS(rc))
778	{
779	pAioMgrNew->fFailsafe = pEpClass->fFailsafe;
780
781	rc = RTSemEventCreate(&pAioMgrNew->EventSem);
782	if (RT_SUCCESS(rc))
783	{
784	rc = RTSemEventCreate(&pAioMgrNew->EventSemBlock);
785	if (RT_SUCCESS(rc))
786	{
787	rc = RTCritSectInit(&pAioMgrNew->CritSectBlockingEvent);
788	if (RT_SUCCESS(rc))
789	{
790	rc = RTThreadCreateF(&pAioMgrNew->Thread,
791	pAioMgrNew->fFailsafe
792	? pdmacFileAioMgrFailsafe
793	: pdmacFileAioMgrNormal,
794	pAioMgrNew,
795	0,
796	RTTHREADTYPE_IO,
797	0,
798	"AioMgr%d-%s", pEpClass->cAioMgrs,
799	pEpClass->fFailsafe
800	? "F"
801	: "N");
802	if (RT_SUCCESS(rc))
803	{
804	/* Link it into the list. */
805	RTCritSectEnter(&pEpClass->CritSect);
806	pAioMgrNew->pNext = pEpClass->pAioMgrHead;
807	if (pEpClass->pAioMgrHead)
808	pEpClass->pAioMgrHead->pPrev = pAioMgrNew;
809	pEpClass->pAioMgrHead = pAioMgrNew;
810	pEpClass->cAioMgrs++;
811	RTCritSectLeave(&pEpClass->CritSect);
812
813	*ppAioMgr = pAioMgrNew;
814
815	Log(("PDMAC: Successfully created new file AIO Mgr {%s}\n", RTThreadGetName(pAioMgrNew->Thread)));
816	return VINF_SUCCESS;
817	}
818	RTCritSectDelete(&pAioMgrNew->CritSectBlockingEvent);
819	}
820	RTSemEventDestroy(pAioMgrNew->EventSem);
821	}
822	RTSemEventDestroy(pAioMgrNew->EventSemBlock);
823	}
824	MMR3HeapFree(pAioMgrNew);
825	}
826
827	LogFlowFunc((": Leave rc=%Rrc\n", rc));
828
829	return rc;
830	}
831
832	/**
833	* Destroys a async I/O manager.
834	*
835	* @returns nothing.
836	* @param pAioMgr The async I/O manager to destroy.
837	*/
838	static void pdmacFileAioMgrDestroy(PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile, PPDMACEPFILEMGR pAioMgr)
839	{
840	/* A normal manager may have still endpoints attached and has to return them. */
841	Assert(pAioMgr->fFailsafe);
842	int rc = pdmacFileAioMgrShutdown(pAioMgr);
843	AssertRC(rc);
844
845	/* Unlink from the list. */
846	rc = RTCritSectEnter(&pEpClassFile->CritSect);
847	AssertRC(rc);
848
849	PPDMACEPFILEMGR pPrev = pAioMgr->pPrev;
850	PPDMACEPFILEMGR pNext = pAioMgr->pNext;
851
852	if (pPrev)
853	pPrev->pNext = pNext;
854	else
855	pEpClassFile->pAioMgrHead = pNext;
856
857	if (pNext)
858	pNext->pPrev = pPrev;
859
860	pEpClassFile->cAioMgrs--;
861
862	rc = RTCritSectLeave(&pEpClassFile->CritSect);
863	AssertRC(rc);
864
865	/* Free the ressources. */
866	RTCritSectDelete(&pAioMgr->CritSectBlockingEvent);
867	RTSemEventDestroy(pAioMgr->EventSem);
868	MMR3HeapFree(pAioMgr);
869	}
870
871	static int pdmacFileInitialize(PPDMASYNCCOMPLETIONEPCLASS pClassGlobals, PCFGMNODE pCfgNode)
872	{
873	int rc = VINF_SUCCESS;
874	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pClassGlobals;
875
876	/** @todo: Change when the RTFileAio* API is used */
877	pEpClassFile->fFailsafe = true;
878
879	/* Init critical section. */
880	rc = RTCritSectInit(&pEpClassFile->CritSect);
881	return rc;
882	}
883
884	static void pdmacFileTerminate(PPDMASYNCCOMPLETIONEPCLASS pClassGlobals)
885	{
886	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pClassGlobals;
887
888	/* All endpoints should be closed at this point. */
889	AssertMsg(!pEpClassFile->Core.pEndpointsHead, ("There are still endpoints left\n"));
890
891	/* Destroy all left async I/O managers. */
892	while (pEpClassFile->pAioMgrHead)
893	pdmacFileAioMgrDestroy(pEpClassFile, pEpClassFile->pAioMgrHead);
894
895	RTCritSectDelete(&pEpClassFile->CritSect);
896	}
897
898	static int pdmacFileEpInitialize(PPDMASYNCCOMPLETIONENDPOINT pEndpoint,
899	const char *pszUri, uint32_t fFlags)
900	{
901	int rc = VINF_SUCCESS;
902	PPDMASYNCCOMPLETIONENDPOINTFILE pEpFile = (PPDMASYNCCOMPLETIONENDPOINTFILE)pEndpoint;
903	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->pEpClass;
904
905	unsigned fFileFlags = fFlags & PDMACEP_FILE_FLAGS_READ_ONLY
906	? RTFILE_O_READ \| RTFILE_O_OPEN \| RTFILE_O_DENY_NONE
907	: RTFILE_O_READWRITE \| RTFILE_O_OPEN \| RTFILE_O_DENY_WRITE;
908
909	if (!pEpClassFile->fFailsafe)
910	fFlags \|= RTFILE_O_ASYNC_IO;
911
912	rc = RTFileOpen(&pEpFile->File, pszUri, fFileFlags);
913	if (RT_SUCCESS(rc))
914	{
915	/* Initialize the cache */
916	rc = MMR3HeapAllocZEx(pEpClassFile->Core.pVM, MM_TAG_PDM_ASYNC_COMPLETION,
917	sizeof(PDMACTASKFILESEG),
918	(void **)&pEpFile->pSegmentsFreeHead);
919	if (RT_SUCCESS(rc))
920	{
921	/** @todo Check caching flag. */
922	PPDMACEPFILEMGR pAioMgr = NULL;
923
924	pEpFile->pSegmentsFreeTail = pEpFile->pSegmentsFreeHead;
925	pEpFile->cSegmentsCached = 0;
926
927	if (pEpClassFile->fFailsafe)
928	{
929	/* Safe mode. Every file has its own async I/O manager. */
930	rc = pdmacFileAioMgrCreate(pEpClassFile, &pAioMgr);
931	AssertRC(rc);
932	}
933	else
934	{
935	/* Check for an idling one or create new if not found */
936	AssertMsgFailed(("Implement\n"));
937	}
938
939	/* Assign the endpoint to the thread. */
940	pEpFile->pAioMgr = pAioMgr;
941	rc = pdmacFileAioMgrAddEndpoint(pAioMgr, pEpFile);
942	}
943
944	if (RT_FAILURE(rc))
945	RTFileClose(pEpFile->File);
946	}
947
948	return rc;
949	}
950
951	static int pdmacFileEpClose(PPDMASYNCCOMPLETIONENDPOINT pEndpoint)
952	{
953	PPDMASYNCCOMPLETIONENDPOINTFILE pEpFile = (PPDMASYNCCOMPLETIONENDPOINTFILE)pEndpoint;
954	PPDMASYNCCOMPLETIONEPCLASSFILE pEpClassFile = (PPDMASYNCCOMPLETIONEPCLASSFILE)pEndpoint->pEpClass;
955
956	/* Make sure that all tasks finished for this endpoint. */
957	int rc = pdmacFileAioMgrCloseEndpoint(pEpFile->pAioMgr, pEpFile);
958	AssertRC(rc);
959
960	/* Remove the endpoint from the thread. */
961	rc = pdmacFileAioMgrRemoveEndpoint(pEpFile->pAioMgr, pEpFile);
962	AssertRC(rc);
963
964	/*
965	* If the async I/O manager is in failsafe mode this is the only endpoint
966	* he processes and thus can be destroyed now.
967	*/
968	if (pEpFile->pAioMgr->fFailsafe)
969	pdmacFileAioMgrDestroy(pEpClassFile, pEpFile->pAioMgr);
970
971	/* Free cached segments. */
972	PPDMACTASKFILESEG pSeg = pEpFile->pSegmentsFreeHead;
973
974	while (pSeg)
975	{
976	PPDMACTASKFILESEG pSegFree = pSeg;
977	pSeg = pSeg->pNext;
978	MMR3HeapFree(pSegFree);
979	}
980
981	/* Free the cached data. */
982	Assert(!pEpFile->fCaching);
983
984	return VINF_SUCCESS;
985	}
986
987	static int pdmacFileEpRead(PPDMASYNCCOMPLETIONTASK pTask,
988	PPDMASYNCCOMPLETIONENDPOINT pEndpoint, RTFOFF off,
989	PCPDMDATASEG paSegments, size_t cSegments,
990	size_t cbRead)
991	{
992	return pdmacFileEpTaskInitiate(pTask, pEndpoint, off, paSegments, cSegments, cbRead, true);
993	}
994
995	static int pdmacFileEpWrite(PPDMASYNCCOMPLETIONTASK pTask,
996	PPDMASYNCCOMPLETIONENDPOINT pEndpoint, RTFOFF off,
997	PCPDMDATASEG paSegments, size_t cSegments,
998	size_t cbWrite)
999	{
1000	return pdmacFileEpTaskInitiate(pTask, pEndpoint, off, paSegments, cSegments, cbWrite, false);
1001	}
1002
1003	static int pdmacFileEpFlush(PPDMASYNCCOMPLETIONTASK pTask,
1004	PPDMASYNCCOMPLETIONENDPOINT pEndpoint)
1005	{
1006	PPDMASYNCCOMPLETIONENDPOINTFILE pEpFile = (PPDMASYNCCOMPLETIONENDPOINTFILE)pEndpoint;
1007	PPDMASYNCCOMPLETIONTASKFILE pTaskFile = (PPDMASYNCCOMPLETIONTASKFILE)pTask;
1008
1009	pTaskFile->fFlush = true;
1010	pdmacFileEpAddTask(pEpFile, pTaskFile);
1011
1012	return VINF_SUCCESS;
1013	}
1014
1015	static int pdmacFileEpGetSize(PPDMASYNCCOMPLETIONENDPOINT pEndpoint, uint64_t *pcbSize)
1016	{
1017	PPDMASYNCCOMPLETIONENDPOINTFILE pEpFile = (PPDMASYNCCOMPLETIONENDPOINTFILE)pEndpoint;
1018
1019	return RTFileGetSize(pEpFile->File, pcbSize);
1020	}
1021
1022	const PDMASYNCCOMPLETIONEPCLASSOPS g_PDMAsyncCompletionEndpointClassFile =
1023	{
1024	/* u32Version */
1025	PDMAC_EPCLASS_OPS_VERSION,
1026	/* pcszName */
1027	"File",
1028	/* enmClassType */
1029	PDMASYNCCOMPLETIONEPCLASSTYPE_FILE,
1030	/* cbEndpointClassGlobal */
1031	sizeof(PDMASYNCCOMPLETIONEPCLASSFILE),
1032	/* cbEndpoint */
1033	sizeof(PDMASYNCCOMPLETIONENDPOINTFILE),
1034	/* cbTask */
1035	sizeof(PDMASYNCCOMPLETIONTASKFILE),
1036	/* pfnInitialize */
1037	pdmacFileInitialize,
1038	/* pfnTerminate */
1039	pdmacFileTerminate,
1040	/* pfnEpInitialize. */
1041	pdmacFileEpInitialize,
1042	/* pfnEpClose */
1043	pdmacFileEpClose,
1044	/* pfnEpRead */
1045	pdmacFileEpRead,
1046	/* pfnEpWrite */
1047	pdmacFileEpWrite,
1048	/* pfnEpFlush */
1049	pdmacFileEpFlush,
1050	/* pfnEpGetSize */
1051	pdmacFileEpGetSize,
1052	/* u32VersionEnd */
1053	PDMAC_EPCLASS_OPS_VERSION
1054	};
1055

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source: vbox/trunk/src/VBox/VMM/PDMAsyncCompletionFile.cpp@ 20368

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