/* $Id: PDMAsyncCompletionFileFailsafe.cpp 96407 2022-08-22 17:43:14Z vboxsync $ */ /** @file * PDM Async I/O - Transport data asynchronous in R3 using EMT. * Simple File I/O manager. */ /* * Copyright (C) 2006-2022 Oracle and/or its affiliates. * * This file is part of VirtualBox base platform packages, as * available from https://www.virtualbox.org. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation, in version 3 of the * License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . * * SPDX-License-Identifier: GPL-3.0-only */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #define LOG_GROUP LOG_GROUP_PDM_ASYNC_COMPLETION #include #include #include #include "PDMAsyncCompletionFileInternal.h" /** * Put a list of tasks in the pending request list of an endpoint. */ DECLINLINE(void) pdmacFileAioMgrEpAddTaskList(PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint, PPDMACTASKFILE pTaskHead) { /* Add the rest of the tasks to the pending list */ if (!pEndpoint->AioMgr.pReqsPendingHead) { Assert(!pEndpoint->AioMgr.pReqsPendingTail); pEndpoint->AioMgr.pReqsPendingHead = pTaskHead; } else { Assert(pEndpoint->AioMgr.pReqsPendingTail); pEndpoint->AioMgr.pReqsPendingTail->pNext = pTaskHead; } /* Update the tail. */ while (pTaskHead->pNext) pTaskHead = pTaskHead->pNext; pEndpoint->AioMgr.pReqsPendingTail = pTaskHead; pTaskHead->pNext = NULL; } /** * Processes a given task list for assigned to the given endpoint. */ static int pdmacFileAioMgrFailsafeProcessEndpointTaskList(PPDMACEPFILEMGR pAioMgr, PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint, PPDMACTASKFILE pTasks) { int rc = VINF_SUCCESS; while (pTasks) { RTMSINTERVAL msWhenNext; PPDMACTASKFILE pCurr = pTasks; if (!pdmacEpIsTransferAllowed(&pEndpoint->Core, (uint32_t)pCurr->DataSeg.cbSeg, &msWhenNext)) { pAioMgr->msBwLimitExpired = RT_MIN(pAioMgr->msBwLimitExpired, msWhenNext); break; } pTasks = pTasks->pNext; switch (pCurr->enmTransferType) { case PDMACTASKFILETRANSFER_FLUSH: { rc = RTFileFlush(pEndpoint->hFile); break; } case PDMACTASKFILETRANSFER_READ: case PDMACTASKFILETRANSFER_WRITE: { if (pCurr->enmTransferType == PDMACTASKFILETRANSFER_READ) { rc = RTFileReadAt(pEndpoint->hFile, pCurr->Off, pCurr->DataSeg.pvSeg, pCurr->DataSeg.cbSeg, NULL); } else { if (RT_UNLIKELY((uint64_t)pCurr->Off + pCurr->DataSeg.cbSeg > pEndpoint->cbFile)) { ASMAtomicWriteU64(&pEndpoint->cbFile, pCurr->Off + pCurr->DataSeg.cbSeg); RTFileSetSize(pEndpoint->hFile, pCurr->Off + pCurr->DataSeg.cbSeg); } rc = RTFileWriteAt(pEndpoint->hFile, pCurr->Off, pCurr->DataSeg.pvSeg, pCurr->DataSeg.cbSeg, NULL); } break; } default: AssertMsgFailed(("Invalid transfer type %d\n", pTasks->enmTransferType)); } pCurr->pfnCompleted(pCurr, pCurr->pvUser, rc); pdmacFileTaskFree(pEndpoint, pCurr); } if (pTasks) { /* Add the rest of the tasks to the pending list */ pdmacFileAioMgrEpAddTaskList(pEndpoint, pTasks); } return VINF_SUCCESS; } static int pdmacFileAioMgrFailsafeProcessEndpoint(PPDMACEPFILEMGR pAioMgr, PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint) { int rc = VINF_SUCCESS; PPDMACTASKFILE pTasks = pEndpoint->AioMgr.pReqsPendingHead; pEndpoint->AioMgr.pReqsPendingHead = NULL; pEndpoint->AioMgr.pReqsPendingTail = NULL; /* Process the request pending list first in case the endpoint was migrated due to an error. */ if (pTasks) rc = pdmacFileAioMgrFailsafeProcessEndpointTaskList(pAioMgr, pEndpoint, pTasks); if (RT_SUCCESS(rc)) { pTasks = pdmacFileEpGetNewTasks(pEndpoint); if (pTasks) rc = pdmacFileAioMgrFailsafeProcessEndpointTaskList(pAioMgr, pEndpoint, pTasks); } return rc; } /** * A fallback method in case something goes wrong with the normal * I/O manager. */ DECLCALLBACK(int) pdmacFileAioMgrFailsafe(RTTHREAD hThreadSelf, void *pvUser) { int rc = VINF_SUCCESS; PPDMACEPFILEMGR pAioMgr = (PPDMACEPFILEMGR)pvUser; NOREF(hThreadSelf); while ( (pAioMgr->enmState == PDMACEPFILEMGRSTATE_RUNNING) || (pAioMgr->enmState == PDMACEPFILEMGRSTATE_SUSPENDING)) { ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, true); if (!ASMAtomicReadBool(&pAioMgr->fWokenUp)) rc = RTSemEventWait(pAioMgr->EventSem, pAioMgr->msBwLimitExpired); ASMAtomicWriteBool(&pAioMgr->fWaitingEventSem, false); Assert(RT_SUCCESS(rc) || rc == VERR_TIMEOUT); LogFlow(("Got woken up\n")); ASMAtomicWriteBool(&pAioMgr->fWokenUp, false); /* Process endpoint events first. */ PPDMASYNCCOMPLETIONENDPOINTFILE pEndpoint = pAioMgr->pEndpointsHead; while (pEndpoint) { pAioMgr->msBwLimitExpired = RT_INDEFINITE_WAIT; rc = pdmacFileAioMgrFailsafeProcessEndpoint(pAioMgr, pEndpoint); AssertRC(rc); pEndpoint = pEndpoint->AioMgr.pEndpointNext; } /* Now check for an external blocking event. */ if (pAioMgr->fBlockingEventPending) { switch (pAioMgr->enmBlockingEvent) { case PDMACEPFILEAIOMGRBLOCKINGEVENT_ADD_ENDPOINT: { PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointNew = pAioMgr->BlockingEventData.AddEndpoint.pEndpoint; AssertMsg(RT_VALID_PTR(pEndpointNew), ("Adding endpoint event without a endpoint to add\n")); pEndpointNew->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_ACTIVE; pEndpointNew->AioMgr.pEndpointNext = pAioMgr->pEndpointsHead; pEndpointNew->AioMgr.pEndpointPrev = NULL; if (pAioMgr->pEndpointsHead) pAioMgr->pEndpointsHead->AioMgr.pEndpointPrev = pEndpointNew; pAioMgr->pEndpointsHead = pEndpointNew; pAioMgr->cEndpoints++; /* * Process the task list the first time. There might be pending requests * if the endpoint was migrated from another endpoint. */ rc = pdmacFileAioMgrFailsafeProcessEndpoint(pAioMgr, pEndpointNew); AssertRC(rc); break; } case PDMACEPFILEAIOMGRBLOCKINGEVENT_REMOVE_ENDPOINT: { PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointRemove = pAioMgr->BlockingEventData.RemoveEndpoint.pEndpoint; AssertMsg(RT_VALID_PTR(pEndpointRemove), ("Removing endpoint event without a endpoint to remove\n")); pEndpointRemove->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_REMOVING; PPDMASYNCCOMPLETIONENDPOINTFILE pPrev = pEndpointRemove->AioMgr.pEndpointPrev; PPDMASYNCCOMPLETIONENDPOINTFILE pNext = pEndpointRemove->AioMgr.pEndpointNext; if (pPrev) pPrev->AioMgr.pEndpointNext = pNext; else pAioMgr->pEndpointsHead = pNext; if (pNext) pNext->AioMgr.pEndpointPrev = pPrev; pAioMgr->cEndpoints--; break; } case PDMACEPFILEAIOMGRBLOCKINGEVENT_CLOSE_ENDPOINT: { PPDMASYNCCOMPLETIONENDPOINTFILE pEndpointClose = pAioMgr->BlockingEventData.CloseEndpoint.pEndpoint; AssertMsg(RT_VALID_PTR(pEndpointClose), ("Close endpoint event without a endpoint to Close\n")); pEndpointClose->enmState = PDMASYNCCOMPLETIONENDPOINTFILESTATE_CLOSING; /* Make sure all tasks finished. */ rc = pdmacFileAioMgrFailsafeProcessEndpoint(pAioMgr, pEndpointClose); AssertRC(rc); break; } case PDMACEPFILEAIOMGRBLOCKINGEVENT_SHUTDOWN: pAioMgr->enmState = PDMACEPFILEMGRSTATE_SHUTDOWN; break; case PDMACEPFILEAIOMGRBLOCKINGEVENT_SUSPEND: pAioMgr->enmState = PDMACEPFILEMGRSTATE_SUSPENDING; break; case PDMACEPFILEAIOMGRBLOCKINGEVENT_RESUME: pAioMgr->enmState = PDMACEPFILEMGRSTATE_RUNNING; break; default: AssertMsgFailed(("Invalid event type %d\n", pAioMgr->enmBlockingEvent)); } ASMAtomicWriteBool(&pAioMgr->fBlockingEventPending, false); pAioMgr->enmBlockingEvent = PDMACEPFILEAIOMGRBLOCKINGEVENT_INVALID; /* Release the waiting thread. */ rc = RTSemEventSignal(pAioMgr->EventSemBlock); AssertRC(rc); } } return rc; }